JP2018021657A - Vehicle drum brake device and vehicle equipped with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the operation feeling of a brake pedal by applying at least one of a front wheel braking device and a rear wheel braking device to a front-rear interlocking braking device of a vehicle constituted by a drum braking device. To provide a brake device for a vehicle that can perform the operation. An end portion of a brake rod 45 of a drum brake device 25 moves along a guide portion 73 of a guide member 47. The guide portion 73 has an engaging portion 73a with which the end portion of the brake rod 45 can be engaged, and a non-engaging portion excluding the engaging portion 73a. When the end portion of the brake rod 45 is located at the non-engagement portion of the guide portion 73, the operating force of the brake pedal 53 is transmitted to the cam lever 43 via the spring member 49. When the end portion of the brake rod 45 is engaged with the engaging portion 73a, as the operating force of the brake pedal 53 increases, the operating force is exclusively transmitted to the cam lever 43 via the brake rod 45. Like [Selection diagram] Figure 2

Description

  The present invention relates to a drum brake device applicable to a vehicle provided with a front-rear interlocking brake device.

The conventional vehicle front-rear interlocking brake device disclosed in Patent Document 1 includes a hydraulic brake device on the front wheel side and a drum brake device on the rear wheel side. When the driver depresses the rear brake pedal arm 31 and rotates the brake pedal 30 in the direction of the arrow c so that an operating force exceeding the set load acts on the delay spring DS, the operating force F is equalized to the equalizer. By 40, the front wheel brake operating force Ff and the rear wheel brake operating force Fr are distributed. The front wheel brake operating force Ff pushes the master piston 51 of the master cylinder 50, and its hydraulic pressure is supplied to the hydraulic chamber 63 of the front wheel master cylinder 60 through the conduit 53 and the release port 65, and the hydraulic pressure is hydraulic. The front wheel brake BF which is a brake device is operated.
On the other hand, the rear wheel brake operation force Fr operates the rear wheel brake BR, which is a drum brake device, via the rear brake transmission system.

Further, the vehicle front-rear interlocking brake device disclosed in Patent Document 2 is configured by a drum brake device on both the front wheel side and the rear wheel side. The interlock brake lever 10 _1, operates as an operating force exceeding the set load to the delay spring 20 acts, first leading the input cable 24 _1, the pulled central portion of the equalizer lever 17, the equalizer lever 17 whole rises, thereby pulling the first output cable 25 _1, the front wheel brake Bf and the rear wheel brake Br is actuated by pulling the second output cable 25 _2.

Japanese Patent No. 5887240 Japanese Patent No. 4233678

However, in the conventional vehicle front-rear interlocking brake device disclosed in Patent Document 1, in order to operate the front wheel brake BF in addition to the rear wheel brake BR, an operating force exceeding the set load acts on the delay spring DS. Therefore, it is necessary to depress the brake pedal 30. On the other hand, until the set load of the delay spring DS is reached, it is necessary to depress the brake pedal 30 to some extent and start the operation of the rear wheel brake BR first. However, since there is a gap provided between the outer peripheral surface of the brake shoe of the rear wheel brake BR and the inner peripheral surface of the brake drum to prevent the brake from rubbing during traveling, It is necessary to depress the brake pedal 30 to some extent before the brake drum is brought into contact with the rear wheel brake BR to operate and the braking force is actually generated.
Even if an operating force exceeding the set load is applied to the delay spring DS, the front wheel brake BF is not yet operated when the set load is exceeded, and the brake caliper pad and brake disc of the front wheel brake BF are not yet operated. A gap is provided between the plate and the brake to prevent the brake from rubbing during traveling.

Accordingly, it is necessary to further depress the brake pedal 30 until the front wheel brake BF starts to operate and the brake caliper pad and the brake disc plate come into contact with each other and the braking force actually starts to be generated.
As a result, there has been a problem that the operation amount of the brake pedal 30 necessary for operating the front wheel brake BF and the rear wheel brake BR in an interlocked manner increases, and the operation feeling of the brake pedal 30 is impaired.
Such problems similarly occur in interlocking brake system before and after a vehicle disclosed in Patent Document 2, the operation amount of the interlock brake lever 10 ₁ required for interlocking actuate the front wheel brake Bf and the rear wheel brake Br increased, there is a problem that the operation feeling of the interlock brake lever 10 ₁ is impaired.

  The present invention has been made to solve such a problem, and is a vehicle front / rear interlocking brake device in which at least one of a front wheel braking device and a rear wheel braking device is constituted by a drum brake device. An object of the present invention is to provide a brake device for a vehicle that can improve the operation feeling of the brake operator by applying.

  In order to achieve this object, a vehicle brake device according to the present invention is a drum brake device in which at least one of a front wheel brake device that brakes front wheels and a rear wheel brake device that brakes rear wheels is a drum brake device. In the vehicular brake device configured to operate both brake devices simultaneously by operating one brake operator, the drum brake device includes an annular brake drum and a slide on the inner peripheral surface of the brake drum. A brake shoe having a contactable friction surface; a camshaft for expanding the brake shoe; and a cam lever having one end fixed to the camshaft and rotating the camshaft about its axis; The operating force of the operating element is transmitted to the cam lever via the operating force transmitting means to rotate the cam lever, and the operating force transmitting means When the operation force of the brake operator starts to be applied, the first operation force transmission member that transmits the operation force to the first action point of the cam lever and the applied operation force of the brake operator increase. And a second operating force transmission member that exclusively transmits the operating force to the second operating point of the cam lever, and the second operating point is in relation to the axis of the cam shaft. It is characterized by being positioned at a position separated from the first action point.

  A vehicle brake device according to a second aspect of the present invention is the vehicle brake device according to the first aspect, wherein the operating force transmitting means is connected to the brake operating element via the connecting means and the connecting means. And the first operating force transmission member is constituted by a spring means, while the second operating force transmission member is constituted by a brake rod, and one end portion of the spring means is the cam lever. The other end of the spring means is rotatably connected to the guide member, and the one end of the brake rod is the second action point of the cam lever. The other end of the brake rod is connected to the guide member so as to be movable relative to the guide member, and the relative movement of the brake rod follows the guide portion formed on the guide member. The guide portion has an engaging portion with which the other end portion of the brake rod can be engaged, and a non-engaging portion excluding the engaging portion. The other end portion of the brake rod is moved from the non-engagement portion of the guide portion toward the engagement portion and engages with the engagement portion as the operating force increases in the process of When the other end of the brake rod is positioned at the non-engaging portion of the guide portion, the operating force of the brake operator is transmitted to the cam lever via the spring means, while the brake When the other end portion of the rod is engaged with the engaging portion of the guide portion, as the operating force of the brake operator increases, the operating force is exclusively applied to the cam lever via the brake rod. It is configured to be transmitted Than is.

According to a third aspect of the present invention, there is provided the vehicle brake device according to the second aspect, wherein the brake rod is a spring so that the other end portion of the brake rod contacts the guide portion. It is characterized by being always energized by the mechanism.
According to a fourth aspect of the present invention, there is provided the vehicle brake device according to the second or third aspect, wherein the guide member is rotatable to the connecting means via a rotation shaft. The rotating shaft is moved together with the guide member when the operating force of the brake operator is transmitted through the connecting means, and the guide is operated by a cam mechanism based on the movement of the rotating shaft. By rotating the member around the axis of the rotation shaft, the rotation angle of the guide member and the movement position of the rotation shaft when rotating are uniformly associated with each other. It is characterized by that.
According to a fifth aspect of the present invention, there is provided the vehicle brake apparatus according to the fourth aspect, wherein the connecting portion where the other end of the spring means is connected to the guide member is the rotating shaft. It is characterized by being positioned in the vicinity of.
A vehicle brake device according to a sixth aspect of the present invention is the vehicle brake device according to the fourth or fifth aspect, wherein the cam mechanism includes a cam portion formed on the guide member, and the rotation. A contact member that can move relative to the guide member along the cam portion as the shaft moves is provided.

According to a seventh aspect of the present invention, there is provided the vehicle brake device according to the sixth aspect, wherein the guide member is moved by the cam mechanism based on the movement of the rotation shaft. In the case of rotating around the axis, when the amount of change in the rotation angle of the guide member while the rotation shaft moves by a unit movement amount is defined as an angle change degree, the contact member is relatively moved. In the region of the cam portion, a first region where the angle change is suddenly changed and a second region where the angle change is set to 0 or near 0 are provided, and the operating force of the brake operator is reduced. As it increases, the abutting member relatively moves from the first region of the cam portion toward the second region, and the first region is brought into contact with the second region. When the members are moving relative to each other, The other end of the kill rod disengages the non-engaging portion of the guide portion and engages with the engaging portion of the guide portion, and the abutting member relatively moves in the second region of the cam portion. The brake rod is configured so that the other end portion of the brake rod is engaged with the engagement portion of the guide portion.
The vehicle brake device according to an eighth aspect of the present invention is the vehicle brake device according to any one of the second to seventh aspects, wherein the guide portion of the guide member includes a long hole, The engaging portion is formed at one end portion or a middle portion in the longitudinal direction of the guide portion, and the guide member is connected to the other end portion in a state where the other end portion of the brake rod is inserted into the guide portion. It is characterized by.
A vehicle brake device according to a ninth aspect of the present invention is the vehicle brake device according to any one of the second to eighth aspects, wherein the other end portion of the brake rod is engaged with the guide portion. When engaged with the joint portion, the engagement state is held by the action of a tensile force applied to the guide member by the spring means.
The vehicle brake device according to a tenth aspect of the present invention is the vehicle brake device according to any one of the second to ninth aspects, wherein one end of the spring means is connected to the cam lever. And a position adjusting mechanism capable of adjusting the position of the first action point.
A vehicle according to an eleventh aspect of the present invention is a vehicle equipped with the vehicle brake device according to any one of the first to tenth aspects.

According to the first aspect of the present invention, when the operating force of the brake operator starts to be applied, the operating force is transmitted to the first action point of the cam lever by the first operating force transmission member, while being applied. As the operating force of the brake operator increases, the operating force is transmitted exclusively to the second operating point of the cam lever by the second operating force transmitting member, and the second operating point is the axis of the camshaft. Since it is positioned at a position away from the first action point with respect to the core, suitable braking can be performed without excessively increasing the operation amount and operating force of the brake operator. The operational feeling can be improved.
According to the second aspect of the present invention, the operating force of the brake operator is transmitted to the cam lever via the spring means connected to the first operating point of the cam lever and the brake rod connected to the second operating point of the cam lever. As the operating force increases in the process of operating the brake operator, the operating force is transmitted to the cam lever through the spring means in the first stage, and the brake rod is exclusively used in the second stage. Since it is transmitted to the cam lever via the brake lever, it is possible to perform suitable braking without excessively increasing the operation amount and operating force of the brake operator, and to improve the operation feeling of the brake operator. Can do.

  According to the invention described in claim 3, since the brake rod is always urged by the spring mechanism so that the other end portion of the brake rod abuts on the guide portion, the other end portion of the brake rod is separated from the guide portion. The possibility that a gap is generated between the two members due to the separation will be reduced. For this reason, when the cam lever is rotated around the axis of the cam shaft, the operating force of the brake operating element is transmitted to the cam lever exclusively through the brake rod from the state in which the operating force of the brake operator is transmitted to the cam lever through the spring means. The transition to is made smoothly.

  According to the invention described in claim 4, the rotation angle of the guide member and the movement position of the rotation shaft are uniformly associated with each other by the action of the cam mechanism based on the movement of the rotation shaft. Therefore, the rotation angle position of the guide member (the rotation angle position around the axis of the rotation shaft) when the other end portion of the brake rod is engaged with the engagement portion of the guide portion of the guide member is surely optimal. The rotation angle position can be set.

According to the fifth aspect of the present invention, since the connecting portion where the other end portion of the spring means is connected to the guide member is positioned in the vicinity of the rotating shaft, the shaft of the rotating shaft is pulled by the tensile force of the spring means. The turning force for rotating the guide member around the core is very small. For this reason, it is not necessary to excessively increase the operation force of the brake operator when the guide member is rotated around the axis of the rotation shaft by the action of the cam mechanism against the turning force. Further, after the other end of the brake rod is engaged with the engaging portion of the guide portion of the guide member, the rotation angle position around the axis of the rotation shaft of the guide member is larger than the tensile force of the spring means. Since it is determined solely by the direction of the pulling force by the much larger brake rod, the guide member does not undesirably rotate around the axis of the rotating shaft by the pulling force of the spring means.
According to the sixth aspect of the present invention, the cam mechanism includes a cam portion formed on the guide member, and an abutting member that can move relative to the guide member along the cam portion as the rotation shaft moves. Therefore, the cam mechanism can be configured with a simple structure.

According to the seventh aspect of the present invention, the first region in which the angle change when the guide member rotates about the axis of the rotation shaft is suddenly changed, and the second region in which the angle change is set to 0 or near 0. When the abutting member moves relative to the first area toward the second area as the operating force of the brake operator increases, Since the other end portion of the rod is disengaged from the non-engaging portion of the guide portion and engaged with the engaging portion of the guide portion, the brake rod can be operated without excessively increasing the operation amount of the brake operator. The guide member can be rotated at a rotation angle at which the other end engages with the engaging portion of the guide member.
In addition, when the abutting member is relatively moving in the second region of the cam portion where the degree of angle change is 0 or near 0, the other end portion of the brake rod is engaged with the engaging portion of the guide portion Is configured to be maintained. For this reason, when the braking force of the drum brake device is generated in earnest by rotating the cam lever by the tensile force of the brake rod, the second region of the cam portion and the contact member move relative to each other. The operating force of the brake operator is not wasted as a frictional force or a force for rotating the guide member. As a result, the operation force of the brake operator is effectively used to generate the braking force of the drum brake device.

According to the eighth aspect of the present invention, the guide portion of the guide member is formed of a long hole, and the guide member is connected to the end portion in a state where the end portion of the brake rod is inserted into the guide portion. The configuration in which the guide member is connected to the brake rod and the configuration in which the brake rod is relatively movable with respect to the guide member and the relative movement moves along the guide portion of the guide member are simple configurations. Can be achieved at the same time. Moreover, since the guide part of a guide member consists of a long hole and the engaging part is formed in the one end part or middle part in the longitudinal direction of this long hole, an engaging part can be comprised with a simple structure.
According to the ninth aspect of the invention, when the end portion of the brake rod is engaged with the engaging portion of the guide portion, the engaged state is maintained by the action of the tensile force on the guide member by the spring means. Therefore, it is not necessary to separately provide a special member for maintaining the engaged state.
According to the tenth aspect of the invention, since the position adjusting mechanism capable of adjusting the position of the first action point where the one end of the spring means is connected to the cam lever is provided, the friction surface of the brake shoe is worn. Even if the angular range of rotation of the cam lever required until the brake shoe and the brake drum come into contact with each other increases, the angular range can be returned to an appropriate state.
According to the eleventh aspect of the present invention, since the vehicle brake device according to the present invention is attached to the vehicle, the operation feeling of the brake operator of the vehicle can be improved.

1 is a side view showing an entire vehicle including a vehicle brake device according to a first embodiment of the present invention. It is a figure which expands and shows the drum brake device by the side of the rear wheel in FIG. 1, and the part containing the vicinity. It is a figure which expands a part in FIG. 2, and also fractures | ruptures and shows a part. It is a graph for demonstrating the action | operation of the brake device of the vehicle which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating operation | movement of the drum brake device by the side of the rear wheel in FIG. It is a side view which shows the whole vehicle provided with the brake device of the vehicle which concerns on the 2nd Embodiment of this invention. It is a figure which expands and shows the drum brake device by the side of the rear wheel in FIG. 6, and the part containing the vicinity. It is a figure which expands and shows the part including the drum brake device by the side of the front wheel in FIG. 6, and its vicinity. It is a figure which expands and shows the part enclosed with the ellipse of the dashed-two dotted line in FIG. It is a figure which shows the part containing the drum brake device by the side of the rear wheel in the brake device of the vehicle which concerns on the 3rd Embodiment of this invention, and its vicinity.

It is a figure which expands a part in FIG. 10, and also fracture | ruptures and shows a part further. It is a figure for demonstrating operation | movement of the drum brake apparatus by the side of the rear wheel shown in FIG. It is a figure for demonstrating the operation | movement following the operation | movement shown in FIG. It is sectional drawing which expands and shows the cross section which follows the arrow AA line of the (4) figure of FIG. It is a figure which shows the modification of the brake device of the vehicle which concerns on each 1st thru | or 3rd embodiment of this invention. It is a figure which shows the part including the drum brake device by the side of the rear wheel in the brake device of the vehicle which concerns on the 4th Embodiment of this invention, and its vicinity. It is a figure for demonstrating operation | movement of the drum brake device shown in FIG. FIG. 18 is a diagram for explaining an operation subsequent to the operation shown in FIG. 17. It is a figure for demonstrating the operation | movement following the operation | movement shown in FIG. It is sectional drawing which expands and shows the cross section in alignment with the arrow B-OB line of (5) figure of FIG. 19, and the cross section in alignment with the arrow CC line, respectively. In the drum brake device shown in FIG. 16, it is a figure which shows the relationship between the movement amount of the pin which moves with a connection rod, and the rotation angle when a guide member rotates.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS. In addition, about a part of figure, on account of drawing, the ratio of the scale of each structural member is shown mutually different. What is shown by the code | symbol 1 in FIG. 1 is a motorcycle which is an example of the vehicle provided with the brake device which concerns on this Embodiment. 1 and 2, the direction indicated by the arrow F indicates the front of the vehicle 1. Before and after use with respect to each component of the vehicle 1 in the following description, the left / right and upper / lower terms In the state where the member is assembled to the vehicle 1, the direction when the vehicle 1 is taken and seen is pointed out. A front fork 7 is supported so as to be rotatable around the axis of a steering shaft 5 pivotally supported at the front portion of a vehicle body frame 3 of the vehicle 1, and a front wheel 9 is rotatable at a lower end portion of an outer tube 7 a of the front fork 7. The handle 10 is fixed to the upper end portion of the front fork 7.

A front end portion of the rear arm 13 is pivotally supported on a pivot shaft 11 provided on the vehicle body frame 3, and a rear wheel 15 is pivotally supported on the rear end portion of the rear arm 13. The upper and lower ends of the rear shock absorber 17 that can be expanded and contracted are connected to a middle part in the front-rear direction of the rear arm 13 (a portion closer to the rear end) and the rear part of the vehicle body frame 3, respectively. The rear end portion of 13 is configured to be swingable in the vertical direction. A disc-shaped brake disc plate 21 is fixed to the front wheel 9 so as to be positioned coaxially with the axle 19 that supports the front wheel 9, and the brake disc plate 21 rotates integrally with the front wheel 9. A brake caliper 23 that brakes the rotation of the brake disc plate 21 is fixed to the lower portion of the outer tube 7 a of the front fork 7. The brake disc plate 21 and the brake caliper 23 constitute a “front wheel braking device” in the present invention.
On the other hand, a drum brake device 25 described later is disposed on the rear wheel 15 side.

  The brake caliper 23 disposed on the front wheel 9 side is a hydraulic brake device, and includes three caliper portions 23a, 23b, and 23c. By operating the brake lever 27 supported rotatably in the vicinity of the grip portion 10a of the handle 10 and operating the first master cylinder 29 fixed in the vicinity of the grip portion 10a of the handle 10, the brake fluid pressure is increased. The brake disc is supplied to the caliper portion 23a and the caliper portion 23b of the brake caliper 23 via the brake hose 31, and the brake pads (not shown) of these caliper portions 23a and 23b are brought into pressure contact with the brake disc plate 21 and the brake disc. The rotation of the plate 21 and the front wheel 9 is braked.

  On the other hand, the drum brake device 25 disposed on the rear wheel 15 side includes an annular brake drum 33 and a lid 35 that closes the opening of the brake drum 33. The brake drum 33 and the lid 35 are defined as follows. These shaft cores are disposed so as to be positioned coaxially with the shaft core of the axle 37 that pivotally supports the rear wheel 15. While the brake drum 33 rotates integrally with the rear wheel 15, the lid body 35 is connected to the rear arm 13 via a restriction rod 39 so as not to be rotated along with the rolling of the rear wheel 15. The restriction rod 39 has a front end connected to a middle part in the longitudinal direction of the rear arm 13 (a portion closer to the front end), and a rear end connected to a convex portion 35 a protruding from the lower end of the lid 35. .

  The drum brake device 25 includes a cam shaft 41 extending in parallel with the axle 37, a cam lever 43 having one end fixed to the cam shaft 41 and rotating the cam shaft 41 about its axis, A brake rod 45 whose one end is rotatably connected to the other end (lower end) via a cylindrical rotation shaft 44; a guide member 47 connected to the other end of the brake rod 45; The cam lever 43 and the guide member 47 are each provided with a coil-shaped spring member 49 whose both ends are rotatably connected. The guide member 47 constitutes an “operation force transmission member” according to the present invention, the brake rod 45 constitutes a “second operation force transmission member” according to the present invention, and the spring member 49 refers to “spring means” according to the present invention. And “first operating force transmission member”. The guide member 47 is formed of a flat plate-like member formed in a substantially triangular shape, and both end portions of the spring member 49 are in the vicinity of the upper end portion of the rear end portion of the guide member 47 (a portion corresponding to one of the apexes of the substantially triangular shape). ) And a longitudinally intermediate portion of the cam lever 43, respectively.

  Small holes are formed in the guide member 47 and the cam lever 43, respectively, and hooked portions of the both ends of the spring member 49 are hooked into these small holes, so that the spring member 49 is always in contact with the small holes. Both ends of the spring member 49 are rotatably connected to the guide member 47 and the cam lever 43 in a state where a tensile force is applied. The position in the cam lever 43 of the small hole of the cam lever 43 to which one end of the spring member 49 is connected constitutes the “first action point” in the present invention. The portion of the cam lever 43 to which the end portion of the spring member 49 is connected is a midway portion in the longitudinal direction of the cam lever 43 and is closer to the axis of the cam shaft 41 than the lower end portion of the cam lever 43 to which the brake rod 45 is connected. is there. In other words, the distance between the portion of the cam lever 43 to which the tensile force of the spring member 49 is applied and the axis of the cam shaft 41 is less than half of the distance between the axis of the rotating shaft 44 and the axis of the cam shaft 41. Is set to The cam shaft 41 is supported by the lid body 35 so as to be rotatable around the axis of the cam shaft 41, and a cam lever 43 is fixed to an end portion of the cam shaft 41 protruding to the outside of the lid body 35.

The drum brake device 25 further includes two arc-shaped brake shoes 51 each having a friction surface 51 a that can slide on the inner peripheral surface 33 a of the brake drum 33, and these two arc-shaped brake shoes 51. Are disposed in the brake drum 33 so as to face each other. A spring member (not shown) that urges the inner peripheral surface 33 a of the brake drum 33 and the friction surface 51 a of the brake shoe 51 in a direction to separate is assembled so as to span between the brake shoes 51. By rotating the cam shaft 41 against the urging force of the spring member, the brake shoe 51 is expanded, and the friction surface 51a of the brake shoe 51 is pressed against the inner peripheral surface 33a of the brake drum 33. Has been.
The upper end portion of the bracket 3a is fixed to the lower portion of the body frame 3 by welding, and the rear end portion of the brake pedal 53 is rotatably supported around the axis O1 extending in the left-right direction at the lower portion of the bracket 3a. The front end portion of the brake pedal 53 is configured to be swingable in the vertical direction. The brake pedal 53 is always urged by a return spring (not shown) in the clockwise direction of the shaft core O1, and contacts with a stopper (not shown) at the most rotated position in the clockwise direction of the shaft core O1. It is held in that state. The brake pedal 53 constitutes a “brake operator” in the present invention. The lower end of the lever 55 is supported at the lower portion of the bracket 3a so as to be rotatable around the axis O1, the lever 55 and the brake pedal 53 are connected via a connecting member 57, and the axis O1. It is configured to be able to rotate integrally around.

  A front end portion 59b of an equalizer 59 having an arm portion 59a extending in the vertical direction is rotatably connected to the upper end portion of the lever 55. The equalizer 59 is formed in a substantially square shape when viewed from the side. The lower end portion of the arm portion 59a of the equalizer 59 is rotatably connected to the other end portion of the advance / retreat rod 61a whose one end portion is movably mounted in the cylinder body of the second master cylinder 61. A front end portion of a rod-like link member 63 extending in the front-rear direction is rotatably connected to the upper end portion of the portion 59a. The second master cylinder 61 is fixed by a screw member to a bracket 3b fixed to the lower portion of the vehicle body frame 3 by welding, and is connected to a caliper portion 23c of the brake caliper 23 via a brake hose 65. The rear end portion of the link member 63 is rotatably connected to the front end portion of the connecting rod 67 via a pin 69, and the rear end portion of the connecting rod 67 is connected to the front end portion of the guide member 47 (one of the apexes of a substantially triangular shape). It is connected via a pin 71 so as to be rotatable in the vicinity of the corresponding part). The equalizer 59, the link member 63, and the connecting rod 67 constitute “operation force transmitting means” and “connecting means” in the present invention.

  In the guide member 47, a guide portion 73 formed of a substantially J-shaped long hole is formed from the vicinity of the portion corresponding to the remaining vertex of the substantially triangular vertexes to the central portion of the guide member 47. A bent front end portion of the brake rod 45 extending in the front-rear direction is inserted into the guide portion 73, and a retaining member (not shown) is inserted into the front end portion so that the front end portion does not come out of the guide portion 73. Is fixed. Thus, the bent front end portion of the brake rod 45 is connected to the guide member 47 and can move along the guide portion 73, and can move relative to the guide member 47. An engaging portion 73a with which the front end portion of the brake rod 45 can be engaged is formed at the front end portion of the guide portion 73 (a portion located at a substantially central portion of the guide member 47). The portion of the guide portion 73 excluding the engaging portion 73a constitutes the “non-engaging portion” in the present invention.

  The pivot shaft 44 is inserted into the shaft hole formed in the lower end portion of the cam lever 43 so as to be rotatable around the axis, and the through-hole is inserted into the pivot shaft 44 in a direction perpendicular to the axis. Is drilled, and the rear end of the brake rod 45 is inserted into the through hole. The position of the shaft hole of the cam lever 43 into which the rotating shaft 44 is inserted in the cam lever 43 constitutes the “second operating point” in the present invention. A male screw portion 45 a is formed at the rear portion of the brake rod 45 so that the rear end portion of the brake rod 45 inserted into the through hole of the rotation shaft 44 is positioned so as not to move relative to the rotation shaft 44. The main nut 75 and the sub-nut 77 are screwed to the male screw portion 45 a so as to sandwich the rotating shaft 44. The front part of the main nut 75 has a smaller diameter than the rear part. The front end surface of the main nut 75 is formed as an arc-shaped concave surface along the outer peripheral surface of the rotating shaft 44, and is engaged with the concave surface with a part of the outer peripheral surface of the rotating shaft 44 being in pressure contact. The main nut 75 rotates with respect to the brake rod 45 so as not to fall off. When assembling these nuts 75 and 77, the main nut 75 is positioned at a predetermined position in the longitudinal direction of the brake rod 45 in a state where the sub-nut 77 is screwed up to the front end portion of the male screw portion 45a so as not to interfere. Thereafter, the auxiliary nut 77 may be screwed back toward the rear until it contacts the front surface of the rotation shaft 44.

  A rod support member 79 into which the connecting rod 67 is slidably inserted is fixed to a bracket 13 a fixed to the lower portion of the rear portion of the rear arm 13 by welding with a screw member 81. The through hole of the rod support member 79 in which the connecting rod 67 is inserted is formed such that the hole diameter of the front end portion is smaller than the hole diameter of the other portion, and the connecting rod 67 is smoothly provided at both ends of the through hole in the front-rear direction. A pair of annular bearing members 83 are press-fitted so as to slide. A coiled spring member 85 is disposed between the pair of bearing members 83 in the through hole of the rod support member 79. The connecting rod 67 is always urged rearward by the spring force of the spring member 85.

<Operation of brake device>
Next, an example of the operation of the brake device according to the present embodiment will be described in detail with reference to FIG. 4 and FIG. Here, in order to simplify the explanation, it is assumed that the brake lever 27 is not braked. The (1) to (4) diagrams in FIG. 4 show line graphs, and the horizontal axes of these diagrams all represent time. T1 to t8 in these figures indicate that time has passed in that order. Further, the vertical axis in (1) shows the depression load FP when the brake pedal 53 is depressed, and the vertical axis in (2) shows that the brake pedal 53 is in the counterclockwise direction of the axis O1 in FIG. (3) The vertical axis of FIG. 3 represents the braking force Ff by the caliper portion 23c of the brake caliper 23, and (4) the vertical axis of FIG. 4 represents the drum brake device 25. Represents the braking force Fr.

In order to simplify the description, in FIG. 1 (1), the depression load FP of the brake pedal 53 is gradually increased from the time point t1, and is made constant from the time point t8, and in FIG. It is assumed that it is gradually increased from the time point, made constant from the time point t5, decreased from the time point t6, and further set to 0 after the time point t7.
When the brake pedal 53 is not operated, the advance / retreat rod 61a of the second master cylinder 61 is located at the lowest position. In this state, there is a slight gap between the friction surface 51a of the brake shoe 51 of the drum brake device 25 and the inner peripheral surface 33a of the brake drum 33. In this state, the rotation of the brake drum 33 and the rear wheel 15 is performed. Is not braked. Further, no brake fluid pressure is generated in the caliper portion 23c of the brake caliper 23 communicating with the second master cylinder 61 via the brake hose 65. As a result, there is a slight gap between the brake pad (not shown) of the caliper portion 23c and the brake disc plate 21, and in this state, the rotation of the brake disc plate 21 and the front wheel 9 is not braked.

  Next, when the brake pedal 53 is started to be depressed (time t1 in FIGS. 4A and 4B), the brake pedal 53 starts to rotate, and the angular velocity ω at the time of the rotation gradually increases. To go. Then, the lever 55 rotates to move the equalizer 59 forward, and the advance / retreat rod 61a of the second master cylinder 61 is pushed into the cylinder main body of the second master cylinder 61 along with this, and the link member 63 and the connecting rod. 67 is displaced toward the front. As a result, the brake fluid pressure in the second master cylinder 61 rises and the pressure is supplied into the caliper portion 23 c of the brake caliper 23 via the brake hose 65. Then, the brake fluid pressure in the caliper portion 23c increases and the brake pad (not shown) of the caliper portion 23c and the brake disc plate 21 come into contact with each other (at time t3 in FIG. 3 (3)).

  On the other hand, when the link member 63 and the connecting rod 67 are displaced forward, the guide member 47 is also displaced forward together with these, and the tension of the spring member 49 connected to the guide member 47 is increased. As a result, the cam lever 43 rotates in the clockwise direction of the axis of the cam shaft 41 in FIG. 5, and the brake shoe 51 and the brake drum 33 of the drum brake device 25 approach each other. At this time, the front end portion of the brake rod 45 displaces the guide portion 73 of the guide member 47 toward the engaging portion 73a, but is still located at a portion other than the engaging portion 73a ((1) in FIG. 5). State shown in the figure). For this reason, even if the guide member 47 is displaced forward together with the connecting rod 67, the tensile force due to the displacement is not transmitted to the brake rod 45. As a result, the rotation of the cam lever 43 is performed only by the tensile force of the spring member 49. For this reason, when viewed from the direction along the axis of the axle 37, the axis of the pin 71 is positioned on the virtual straight line L1 passing through the center of the spring member 49 (the state shown in FIG. 5 (1)). .

A portion in the longitudinal direction of the cam lever 43 to which the spring member 49 is connected is located closer to the axis of the cam shaft 41 than the end of the cam lever 43 to which the brake rod 45 is connected (the axis of the rotating shaft 44). is there. In other words, the distance between the portion of the cam lever 43 to which the tensile force of the spring member 49 is applied and the axis of the cam shaft 41 is equal to the axis of the rotating shaft 44 to which the tensile force of the brake rod 45 is applied and the cam shaft 41. It is set to be less than half of the distance from the axis. As a result, the rotation angle of the cam lever 43 with respect to the displacement of the guide member 47 is the case in which the cam lever 43 is rotated by the tensile force of the spring member 49 compared to the case where the cam lever 43 is rotated by the tensile force of the brake rod 45. Will be bigger. For this reason, by rotating the cam lever 43 by the tensile force of the spring member 49, the brake shoe 51 and the brake drum 33 of the drum brake device 25 can be brought into contact with each other with a small depression amount of the brake pedal 53.
The front end portion of the brake rod 45 that has displaced the guide portion 73 of the guide member 47 toward the engaging portion 73a hits the front end of the guide portion 73 immediately before the brake shoe 51 and the brake drum 33 come into contact with each other. Engage with the mating portion 73a (state shown in FIG. 5 (2)). Until this time, although a tensile force is applied to the spring member 49, the spring member 49 hardly expands and the initial load (tensile load) is maintained so that the distance between both ends remains substantially constant, and a large spring constant. The characteristics of the spring member 49 are set.

  In the present embodiment, the timing at which the front end portion of the brake rod 45 abuts against the front end of the guide portion 73 and engages with the engaging portion 73a is immediately before the brake shoe 51 and the brake drum 33 come into contact with each other. However, instead of this, the front end portion of the brake rod 45 abuts the front end of the guide portion 73 substantially simultaneously with or immediately after the contact of the brake shoe 51 and the brake drum 33, and the engaging portion 73a. You may set so that it may engage.

  Furthermore, when the depression load FP of the brake pedal 53 is increased, the spring member 49 starts to extend, and the tensile force of the spring member 49 increases. The tensile force of the spring member 49 is such that the guide member 47 rotates counterclockwise about the axis of the pin 71 in FIG. 5 when the engaging portion 73a of the guide member 47 is pressed forward by the front end portion of the brake rod 45. Stop trying to rotate. In other words, the tensile force of the spring member 49 acts to press the front end portion of the brake rod 45 against the end edge of the engaging portion 73a of the guide portion 73, thereby engaging the front end portion of the brake rod 45. The engaged state with the portion 73a is maintained.

Further, when the depression load FP of the brake pedal 53 is increased, the tensile force due to the brake rod 45 engaged with the engaging portion 73a gradually increases, and the tensile force becomes larger than the tensile force of the spring member 49. As a result, in FIG. 5, the guide member 47 rotates in the clockwise direction of the axis of the pin 71, and is on an imaginary straight line L <b> 2 passing through the axis of the brake rod 45 when viewed from the direction along the axis of the axle 37. The pin 71 is in a substantially positioned state (as shown in FIG. 5 (3)). Before reaching this state, the brake shoe 51 of the drum brake device 25 and the brake drum 33 come into contact with each other (at time t4 in FIG. 4 (4)). In this state, the cam lever 43 is rotated exclusively by the tensile force of the brake rod 45. The distance between the axis of the rotating shaft 44 to which the tensile force of the brake rod 45 acts and the axis of the cam shaft 41 is such that the portion of the cam lever 43 to which the tensile force of the spring member 49 is applied and the axis of the cam shaft 41. Therefore, even if the depression load FP of the brake pedal 53 is the same, the load that rotates the cam lever 43 is greater than that when the cam lever 43 is rotated by the tensile force of the spring member 49. The case where the cam lever 43 is rotated by the pulling force of the rod 45 becomes considerably large.
In FIG. 4, for the sake of simplicity of explanation, the time point t3 in FIG. 3 (3) and the time point t4 in FIG.

Furthermore, when the depression load FP of the brake pedal 53 is increased, the brake fluid pressure in the caliper portion 23c is further increased, the brake pad of the caliper portion 23c and the brake disc plate 21 are in pressure contact, and the pressure contact force gradually increases. . Then, a braking force is applied to the brake disc plate 21 and the front wheel 9 by the pressure contact of the brake pad, and the braking force gradually increases as the depression load FP of the brake pedal 53 increases. Further, the pressure contact force between the brake shoe 51 and the brake drum 33 of the drum brake device 25 gradually increases, and the braking force to the drum brake device 25 and the rear wheel 15 is generated by the pressure contact of the brake shoe 51, and the braking force is applied to the brake pedal. As the stepping load FP 53 increases, it gradually increases.
It should be noted that (1) the gradient after time t2 is steeper than the gradient in which the stepping load FP increases until time t2 in FIG. This is due to the fact that it is substantially the same as the time t4 of FIG. 5 and that the braking force starts to be generated in the caliper portion 23c and the drum brake device 25.

As the depressing load FP of the brake pedal 53 increases, the braking force of the drum brake device 25 further increases, and the brake fluid pressure of the second master cylinder 61 further increases and the braking force by the caliper portion 23c also increases. . As a result, the angular velocity ω of the brake pedal 53 gradually decreases to (0) at time t7 in the figure, but the braking force by the drum brake device 25 and the caliper portion 23c becomes constant after increasing until time t8.
On the other hand, if the depression load FP of the brake pedal 53 is decreased to 0, the pressing force that the front end portion of the brake rod 45 presses against the end edge of the engaging portion 73a of the guide portion 73 decreases as the decrease. At the same time, the tensile force caused by the brake rod 45 engaged with the engaging portion 73a is gradually reduced, and the tensile force becomes smaller than the tensile force of the spring member 49. As a result, the guide member 47 rotates in the counterclockwise direction of the axis of the pin 71 in FIG. 5 due to the tensile force of the spring member 49, and the center of the spring member 49 is viewed from the direction along the axis of the axle 37. The axis of the pin 71 is substantially positioned on the virtual straight line L1 passing through (the same state as the state shown in FIG. 5 (2)).

Then, as the stepping load FP of the brake pedal 53 approaches 0, the lever 55 together with the brake pedal 53 returns to the clockwise direction of the shaft core O1, and the equalizer 59 and the link member 63 are moved rearward. Displace. At this time, the repulsive force of the spring member 85 acts in the extending direction, and the link member 63, the connecting rod 67, and the guide member 47 are also displaced rearward. Further, the cam lever 43 rotates in the counterclockwise direction of the axis of the cam shaft 41, and the front end portion of the brake rod 45 is detached from the engaging portion 73a of the guide member 47 and is the end opposite to the engaging portion 73a. The guide part 73 is displaced toward the part (the same state as shown in FIG. 5A). As a result, the frictional surface 51a of the brake shoe 51 of the drum brake device 25 and the inner peripheral surface 33a of the brake drum 33 are separated from each other by the biasing force of the spring member assembled so as to span between the brake shoes 51. The braking of the device 25 is released. Further, the brake fluid pressure in the caliper portion 23c of the brake caliper 23 decreases, so that the brake pad of the caliper portion 23c and the brake disc plate 21 are separated from each other, and braking of the brake disc plate 21 and the front wheel 9 is also released.
Above, the description regarding the action | operation of the brake device in this Embodiment is complete | finished.

  In the vehicle 1 of the above-described embodiment, an example in which the braking device on the front wheel 9 side is configured by a hydraulic brake device having the brake caliper 23 and the braking device on the rear wheel 15 side is configured by the drum brake device 25 is shown. However, instead of this, the braking device on the front wheel 9 side may be configured by the same as the drum brake device 25, and the braking device on the rear wheel 15 side may be configured by a hydraulic brake device having a brake caliper.

  According to the embodiment of the present invention as described above, the brake pedal 53 is connected via the brake rod 45 connected to the end of the cam lever 43 and the spring member 49 connected to the middle portion of the cam lever 43 in the longitudinal direction. The pedaling force is transmitted to the cam lever 43. As the pedaling force increases in the process of depressing the brake pedal 53, the pedaling force is transmitted to the cam lever 43 through the spring member 49 in the first stage, and the second stage. Then, since it is transmitted exclusively to the cam lever 43 via the brake rod 45, it is possible to perform suitable braking without excessively increasing the depression amount and the depression force of the brake pedal 53, and the operation fee of the brake pedal 53 can be increased. The ring can be made good.

Further, since the guide member 47 is connected to the end portion of the guide member 47 in a state where the end portion of the brake rod 45 is inserted into the guide portion 73, the guide member 47 is connected to the brake rod 45. The configuration and the configuration in which the brake rod 45 can move relative to the guide member 47 and the relative movement moves along the guide portion 73 of the guide member 47 can be simultaneously achieved with a simple configuration. . Further, the guide portion 73 of the guide member 47 is formed of a substantially J-shaped long hole, and an engaging portion 73a is formed at one end portion in the longitudinal direction of the guide portion 73, so that the front end portion of the brake rod 45 is engaged. The engaging portion can be configured with a simple structure.
Furthermore, when the front end portion of the brake rod 45 is engaged with the engagement portion 73a of the guide member 47, the engagement state is maintained by the action of the tensile force applied to the guide member 47 by the spring member 49. Therefore, it is not necessary to separately provide a special member for maintaining the engaged state.

Next, as embodiments according to the present invention other than the above-described embodiments, two other embodiments (second embodiment and third embodiment) will be described below. In the drawings referred to in the description of these two embodiments, the same or equivalent members and parts as those described in the first embodiment described above are denoted by the same reference numerals and detailed description thereof will be omitted. Omitted and embodiments described later will be described mainly in detail with respect to differences from the embodiments described earlier. In the second and third embodiments, it is needless to say that the same actions and effects can be achieved with the same or equivalent configurations as those of the first embodiment described above.
(Second Embodiment)
A second embodiment according to the present invention will be described below in detail with reference to FIGS. In addition, about a part of figure, on account of drawing, the ratio of the scale of each structural member is shown mutually different.

  In the vehicle 1 according to the first embodiment, an example in which the braking device on the front wheel 9 side is configured by a hydraulic brake device having a brake caliper 23 and the braking device on the rear wheel 15 side is configured by a drum brake device 25 is shown. However, in the vehicle 1 ′ of the second embodiment, the braking device on the rear wheel 15 side is the same as the drum brake device 25 of the first embodiment, while the braking device on the front wheel 9 side is configured. The apparatus is constituted by a drum brake device 25 ′ similar to the drum brake device 25 of the first embodiment. Accordingly, with regard to details of the drum brake device 25 ′, the same or equivalent members and parts as those described in the first embodiment are given the same reference numerals, and detailed description thereof is omitted. The drum brake device 25 ′ constitutes a “front wheel braking device” in the present invention.

A front end portion 59b of an equalizer 59 having an arm portion 59a extending in the vertical direction is rotatably connected to the upper end portion of the lever 55. The equalizer 59 is formed in a substantially Y shape when viewed from the side. One end portion of the first brake wire 87 is rotatably connected to the lower end portion of the arm portion 59a of the equalizer 59, and a bar-like link member 63 extending in the front-rear direction is connected to the upper end portion of the arm portion 59a of the equalizer 59. The front end portion is rotatably connected. The other end portion of the first brake wire 87 is connected to one end portion of the second brake wire 91 via a relay device 89 fixed to the front portion of the vehicle body frame 3, and the other end portion of the second brake wire 91 is The rear end of the connecting rod 67 of the drum brake device 25 'is connected. The rod support member 79 into which the connecting rod 67 is slidably inserted is fixed to a convex portion formed integrally with the lower portion of the outer tube 7 a of the front fork 7 by a screw member 81. The lid body 35 of the drum brake device 25 ′ is prevented from rotating by a stopper portion (not shown) formed on the outer tube 7 a of the front fork 7 so as not to be rotated along with the rolling of the front wheel 9.
The connecting rod 67, the first brake wire 87, the relay device 89, and the second brake wire 91 of the drum brake device 25 ′ constitute “operation force transmitting means” and “connecting means” in the present invention.

  In addition, one end of a third brake wire 95 is connected to the brake lever 27 rotatably supported near the grip 10 a of the handle 10, and the other end of the third brake wire 95 is connected to the relay device 89. It is connected. The longitudinal middle portions of the first brake wire 87, the second brake wire 91, and the third brake wire 95 are respectively covered with outer tubes 97, and the brake wires 87, 91, 95 are respectively covered with the outer tubes 97. Are configured to be slidable in the longitudinal direction. One end of the outer tube 97 of the first brake wire 87 is supported by a first stay 99 (see FIG. 7) fixed to the bracket 3a of the vehicle body frame 3 by welding, and the other end of the outer tube 97 is connected to the vehicle body frame. 3 is supported by a substantially U-shaped second stay 101 (see FIG. 9) fixed to the screw 3 by a screw member.

  As shown in FIG. 9, the relay device 89 includes a housing 103 fixed to the front portion of the body frame 3 and a slidably inserted into the housing 103, and one end of the second brake wire 91 is connected to the relay device 89. The slider 105 is provided. The slider 105 has a first through hole 105a through which the first brake wire 87 is slidably inserted and a second through hole 105b through which the third brake wire 95 is slidably inserted. Has been. These through holes 105a and 105b are formed in parallel with each other, and one end portion of the second brake wire 91 is connected to a portion located in the middle between both front openings of these through holes 105a and 105b. A first hook 107a and a second hook 107b are respectively crimped and bonded to the tip portions of the first brake wire 87 and the third brake wire 95 inserted into the through holes 105a and 105b, respectively.

  Thus, when the brake lever 27 is operated, the third brake wire 95 is pulled and the second hook 107b pushes the slider 105, so that the slider is moved relative to the casing 103 of the relay device 89. 105 is relatively moved, the second brake wire 91 is pulled, and the drum brake device 25 'is operated. At this time, although the slider 105 moves, the first brake wire 87 and the first hook 107a are left without being displaced, so that the operating force to the brake lever 27 is applied via the first brake wire 87 to the equalizer. 59, the brake pedal 53 and the like are not transmitted unnecessarily.

  On the other hand, when the brake pedal 53 is depressed, the pedaling force applied to the brake pedal 53 is transmitted to the drum brake device 25 on the rear wheel 15 side via the equalizer 59 as in the first embodiment described above. At the same time, the first brake wire 87 is pulled through the equalizer 59, and the slider 105 is pushed by the first hook 107a. As a result, the slider 105 moves relative to the housing 103 of the relay device 89, the second brake wire 91 is pulled, and the drum brake device 25 ′ is operated. At this time, although the slider 105 moves, the third brake wire 95 and the second hook 107b are left without being displaced, so that the pedal force applied to the brake pedal 53 is braked via the third brake wire 95. The brake lever 27 is not unnecessarily rotated by being transmitted to the lever 27.

  According to this embodiment, not only the braking device on the rear wheel 15 side is the same as the drum braking device 25 of the first embodiment, but also the braking device on the front wheel 9 side is the drum braking device. 25 ′, it is possible to perform suitable braking without excessively increasing the depression amount and the depression force of the brake pedal 53 as compared with the first embodiment, and the brake lever 27 and the brake The operation feeling of the pedal 53 can be further improved.

In the first embodiment described above, the caliper portion 23c of the brake caliper 23 that brakes the front wheel 9 and the drum brake device 25 that brakes the rear wheel 15 are simultaneously operated by operating one brake pedal 53. did. In the second embodiment described above, the drum brake device 25 ′ for braking the front wheel 9 and the drum brake device 25 for braking the rear wheel 15 are simultaneously operated by operating one brake pedal 53. .
However, instead of these forms, the braking devices on the front wheel side and the rear wheel side may be operated simultaneously by operating one brake lever disposed on the handle 10. In this case, the brake lever constitutes a “brake operator” in the present invention.

(Third embodiment)
In each of the first and second embodiments, the example in which the brake device on the rear wheel 15 side is configured by the drum brake device 25 as described above is shown, but instead, this is shown in FIGS. The drum brake device 25 according to the third embodiment may constitute a braking device on the rear wheel 15 side. Hereinafter, a drum brake device 25 according to a third embodiment of the present invention will be described in detail with reference to FIGS. Note that, in these drawings, some of the drawings are illustrated with the ratios of the scales of the constituent members being different from each other for the convenience of drawing.

In the drum brake device 25 according to each of the first and second embodiments, in order to engage the front end portion of the brake rod 45 with the engaging portion 73a of the guide portion 73 of the guide member 47, it is necessary to The rotation angle position of the guide member 47 (the rotation angle position around the axis of the pin 71) is important. This is because if the rotation angle position is not appropriate, the front end portion of the brake rod 45 is positioned on the engaging portion 73a of the guide member 47, and there is a possibility that the engaging portion 73a may not be engaged well.
In the drum brake device 25 according to each of the first and second embodiments, the rotational angle position of the guide member 47 when the front end portion of the brake rod 45 is engaged with the engaging portion 73a of the guide member 47. (A rotational angle position around the axis of the pin 71) is determined by the tension between the brake rod 45 and the spring member 49 and the direction in which the tension acts. Therefore, in order to position the rotation angle position of the guide member 47 at that time at an appropriate position, the tension between the brake rod 45 and the spring member 49 and the direction in which the tension acts become an appropriate value and direction, respectively. Thus, the following items need to be set as appropriate. The matters include the shape of the guide portion 73 of the guide member 47, the position where the guide portion 73 is formed with respect to the guide member 47, the position where both ends of the spring member 49 are connected to the cam lever 43 and the guide member 47, and the cam. Examples include the distance between the shaft 41 and the rotating shaft 44, the length of the brake rod 45, and the spring characteristics of the spring member 49.

  On the other hand, in the drum brake device 25 according to the third embodiment, the rotation angle position of the guide member 47 (the rotation angle around the axis of the pin 71) is caused by the action of the cam mechanism 111 shown in FIG. Position) is set to an appropriate position. The cam mechanism 111 includes a pin 113 having one end fixed to a convex portion 79a projecting from the rear portion of the rod support member 79, and a cam portion 115 of the guide member 47 engaged with the other end of the pin 113. It has. The pin 113 constitutes a “contact member” in the present invention. The pin 113 may be fixed to a bracket fixed to the rear portion of the rear arm 13 by welding instead of the structure fixed to the convex portion 79a projecting from the rod support member 79.

More specifically, a cam portion 115 is formed in a long hole extending in the front-rear direction in front of the guide portion 73 of the flat guide member 47 formed in a substantially trapezoid shape and below the guide member 47. 115 is formed in a long hole whose middle part in the front-rear direction is bent in a square shape at two places.
On the other hand, the brake rod 45 has a sandwiching portion 45b in which a slit 117 (see FIG. 14) having a width slightly larger than the plate thickness of the guide member 47 is formed in the front portion, and a distal end portion (the brake rod 45) of the sandwiching portion 45b. A pin 119 inserted in a shaft hole drilled in the front end of the pin 119, and a nut 121 screwed into a male screw portion 119a carved in one end of the pin 119. The pin 119 is fixed to the distal end portion of the holding portion 45b by screwing the nut 121 into the male screw portion 119a of the pin 119. The brake rod is interposed via the pin 119 in a state where the rear part of the guide member 47 is inserted into the slit 117 of the holding part 45b and the axial center part of the pin 119 is inserted into the guide part 73 of the guide member 47. 45 is rotatably connected to the guide member 47. The engaging portion 73 a of the guide member 47 with which the pin 119 is engaged is formed in the middle portion of the guide portion 73 in the longitudinal direction.
Further, both end portions of the spring member 49 are rotatably connected to a convex portion protruding from the upper portion of the guide member 47 and a midway portion in the longitudinal direction of the cam lever 43.

A midway portion in the longitudinal direction of the torsion spring 123 is wound around the rotating shaft 44, and one end portion 123a of the torsion spring 123 extending forward from the wound portion is bent, and the bent portion is formed. Is hooked in the middle in the longitudinal direction of the brake rod 45. The torsion spring 123 constitutes a “spring mechanism” in the present invention.
On the other hand, the other end portion 123 b extending upward from the portion where the torsion spring 123 is wound around the rotation shaft 44 is also bent, and the bent portion is hooked on the longitudinal middle portion of the cam lever 43. ing. The torsion spring 123 is set so that an initial load is applied to bias the one end portion 123a and the other end portion 123b toward each other. As a result, the brake rod 45 is always urged by the torsion spring 123 so that the outer peripheral surface of the pin 119 of the brake rod 45 abuts on the upper edge of the guide portion 73 of the guide member 47. The configuration in which the torsion spring 123 is provided and urged so that the front end portion of the brake rod 45 abuts on the upper edge of the guide portion 73 of the guide member 47 is related to the first and second embodiments. The drum brake device 25 and the drum brake device 25 ′ may be employed.
Instead of providing the torsion spring 123, both end portions of the coil-shaped spring member to which an initial load (tensile load) is applied are hung on the midway portion in the longitudinal direction of the cam lever 43 and the midway portion in the longitudinal direction of the brake rod 45, respectively. You may make it pass and connect. In this case, the coiled spring member constitutes the “spring mechanism” in the present invention.

<Operation of brake device>
Next, an example of the operation of the brake device according to the third embodiment will be described with reference to FIG. 4 in addition to FIGS. The operation of the brake is performed as described in <Operation of the brake device> in the first embodiment described above. (1) in FIG. 12 corresponds to (1) in FIG. 5 described above, and when the brake pedal 53 is started to be depressed (at time t1 in FIGS. (1) and (2) in FIG. 4), While the brake shoe 51 of the drum brake device 25 and the brake drum 33 approach each other, the pin 119 of the brake rod 45 is located at a portion other than the engaging portion 73 a of the guide portion 73 of the guide member 47. . In this state, the cam lever 43 is rotated only by the tensile force of the spring member 49, and when viewed from the direction along the axis of the axle 37, the axis of the pin 71 is placed on an imaginary straight line L 1 passing through the center of the spring member 49. The wick is located.

Further, when the depression load FP of the brake pedal 53 is increased, the operating force of the brake pedal 53 is transmitted to the pin 71 via the connecting rod 67, and the pin 71 moves forward together with the guide member 47. 12 (2) shows that the pin 71 moves slightly forward compared to FIG. 1 (1) so that the pin 119 of the brake rod 45 is positioned in the vicinity of the engaging portion 73a in the guide portion 73 of the guide member 47. It shows the state.
13 (3) shows that the pin 71 moves slightly forward as compared with FIG. 12 (2), and the pin 119 of the brake rod 45 engages with the guide portion 73 of the guide member 47. The state located in the part 73a is shown. In this state, the pin 119 of the brake rod 45 is positioned at the engaging portion 73a of the guide member 47, but the pin 119 is not yet engaged with the engaging portion 73a, and the brake rod 45 has a tensile force. It has not yet occurred.

  Further, when the depression load FP of the brake pedal 53 is increased, the pin 71 further moves forward together with the guide member 47, and the guide member 47 is moved by the cam mechanism 111 based on the movement of the pin 71. It rotates around the axis. Specifically, the guide member 47 rotates around the axis of the pin 71 by the action of the cam mechanism 111 due to the relative movement of the pin 113 relative to the guide member 47 along the cam portion 115 of the guide member 47. Thereby, the rotation angle of the guide member 47 at the time of the rotation and the moving position of the pin 71 are uniformly associated. FIG. 13 (4) shows that the pin 113 moves relative to the bent portion in the longitudinal direction of the cam portion 115, and the guide member 47 rotates clockwise around the axis of the pin 71 in FIG. Shows the state. This state is a state in which the pin 119 of the brake rod 45 is engaged with the engaging portion 73 a of the guide member 47. In this state, the force to rotate the cam lever 43 clockwise in FIG. 13 (4) is solely due to the tensile force of the brake rod 45.

On the other hand, if the stepping load FP of the brake pedal 53 is reduced to zero, a spring member (not shown) that urges the inner peripheral surface 33a of the brake drum 33 and the friction surface 51a of the brake shoe 51 to separate. ) And the repulsive force of the spring member 85 cause the connecting rod 67 and the pin 71 to move rearward. Based on the movement, the guide member 47 moves around the axis of the pin 71 (FIG. 13) due to the action of the cam mechanism 111 by the pin 113 moving relative to the guide member 47 along the cam portion 115 of the guide member 47. (4) It rotates counterclockwise in the figure. In the process of rotation, the state is the same as the state shown in FIG. As a result, the engagement between the pin 119 of the brake rod 45 and the engaging portion 73a of the guide member 47 is released. Then, as the depressing load FP of the brake pedal 53 approaches 0, the state becomes the same as the state shown in FIG. 12A after passing through the same state as shown in FIG.
Above, the description regarding the action | operation of the brake device which concerns on 3rd Embodiment is complete | finished.

According to this embodiment, the brake rod 45 is always urged by the torsion spring 123 so that the pin 119 of the brake rod 45 abuts against the guide portion 73 of the guide member 47. The possibility that a gap will be generated between the two at a distance from 73 is reduced. For this reason, when the cam lever 43 is rotated about the axis of the cam shaft 41, the pedal force of the brake pedal 53 is transmitted to the cam lever 43 via the spring member 49, and the cam lever 43 is exclusively transmitted via the brake rod 45. The transition to the state transmitted to is smoothly performed.
Further, the cam mechanism 111 based on the movement of the pin 71 is configured so that the rotation angle of the guide member 47 and the movement position of the pin 71 are uniformly associated with each other. The rotation angle position of the guide member 47 (the rotation angle position around the axis of the pin 71) when the pin 119 of the brake rod 45 is engaged with the engagement portion 73a of the 73 is surely set to the optimum rotation angle position. can do.
Furthermore, the cam mechanism 111 includes a pin 113 supported on the vehicle body frame 3 of the vehicle 1 via the rod support member 79 and a cam portion 115 formed on the guide member 47, and the pin 113 includes the cam portion 115. Accordingly, the cam mechanism 111 can be configured with a simple structure.
The configuration of the drum brake device 25 according to the third embodiment described above can also be applied to the drum brake device 25 ′ on the front wheel 9 side in the second embodiment. Needless to say, the configuration of the drum brake device 25 ′ after the application is the same as that of the drum brake device 25 according to the above-described third embodiment, and thus detailed description and drawings are omitted.

Each of the first to third embodiments described above is an example for explaining the present invention, and the present invention is not limited to the above-described embodiments and modifications, and claims. The brake device for a vehicle after such a change is also included in the technical scope of the present invention.
For example, in each of the above-described embodiments, an example of a motorcycle has been shown as a vehicle including the vehicle brake device according to the present invention. It may be a one-wheel, two-wheel rear three-wheel vehicle or a four-wheel vehicle. In these cases, a front wheel braking device is mounted on each front wheel, and a rear wheel braking device is mounted on each rear wheel.

Further, in each of the above-described embodiments, an example has been shown in which the bent portions of the both ends of the spring member 49 are hooked and connected to the small holes of the guide member 47 and the cam lever 43, respectively. As in the drum brake device 25 on the rear wheel 15 side shown in FIG. 15, a position adjustment mechanism that can adjust the connection position of the spring member 49 to the cam lever 43 may be adopted. The position adjusting mechanism shown in FIG. 15 is configured by using the rotating shaft 44 and the main nut 75 described in the above embodiments. The configuration shown in FIG. 15 differs from that of the first embodiment described above only in the position adjusting mechanism, and therefore, the same or equivalent members as those described in the first embodiment are described. The same reference numerals are assigned and detailed description is omitted. More specifically, the cam lever 43 includes a base portion 125 fixed to the middle portion in the longitudinal direction by welding. A rotation shaft 44 is inserted into the shaft hole formed in the base portion 125 so as to be rotatable around the axis, and the through-hole formed in a direction perpendicular to the axis of the rotation shaft 44 is inserted into the through hole. An adjustment rod 127 is inserted. A main nut 75 is screwed into a male screw portion 127a carved in a part of the adjusting rod 127 in the longitudinal direction (a portion excluding the front portion).
The position in the cam lever 43 of the shaft hole of the base 125 into which the rotation shaft 44 is inserted constitutes the “first action point” in the present invention.

The base 125 is made of a plate-like member that is bent in a substantially U shape. The adjustment rod 127 has the same thickness as the brake rod 45 described in each of the above embodiments, and the rear end of the spring member 49 is inserted into a small hole formed in the front end portion of the adjustment rod 127. The part bent and formed in the hook shape of the part is hooked and connected. The spring member 49 and the adjustment rod 127 to which the spring member 49 is connected constitute the “spring means” and the “first operating force transmission member” in the present invention.
Further, the main nut 75 is engaged with the arcuate concave surface of the front end surface thereof while a part of the outer peripheral surface of the rotating shaft 44 is in pressure contact, so that the main nut 75 rotates with respect to the adjustment rod 127. It does not fall out.
In the above-described position adjustment mechanism, the rotating shaft 44 and the main nut 75 described in the above embodiments are used, or the adjustment rod 127 having the same thickness as the brake rod 45 is used. Needless to say, a separate one having a function equivalent to these may be used.

With the biasing force of the spring member assembled so as to span between the brake shoes 51, the biasing force for rotating the camshaft 41 and the cam lever 43 in the counterclockwise direction of the axis of the camshaft 41 in FIG. The arcuate front end surface (concave surface) of the main nut 75 screwed to the adjustment rod 127 and the outer peripheral surface of the rotating shaft 44 by cooperation with the tensile force of the spring member 49 acting against the urging force. And are always in pressure contact in an engaged state. For this reason, the auxiliary nut 77 described in each of the above embodiments is diverted and screwed into the male threaded portion 127a of the adjustment rod 127 so that the rotating shaft 44 is sandwiched between the main nut 75 and the auxiliary nut 77. Also good.
If the above-described position adjustment mechanism is used, the effects can be exhibited in the following situations. That is, the angular range in which the cam lever 43 rotates until the brake shoe 51 and the brake drum 33 come into contact with each other due to wear of the friction surface 51a of the brake shoe 51 due to long-term use of the drum brake device 25. Becomes larger. For this reason, unless the brake pedal 53 is stepped on and rotated a lot, the braking force cannot be generated, and the operation feeling of the brake pedal 53 is deteriorated.

Therefore, in order to return the depression amount of the brake pedal 53 to an appropriate state equivalent to the state before the brake shoe 51 is worn, the main nut 75 is appropriately attached to the adjustment rod 127 according to the wear amount of the brake shoe 51. , And move it forward relative to it. At this time, the sub-nut 77 is screwed in advance to the front end portion of the male screw portion 45a of the brake rod 45 so as not to disturb the relative movement. After the positioning operation of the main nut 75 with respect to the adjustment rod 127 is completed, the positioning operation of the main nut 75 with respect to the brake rod 45 is performed. Twist back against. With the above operation, the angular range in which the cam lever 43 rotates until the brake shoe 51 and the brake drum 33 come into contact with each other can be reduced and returned to an appropriate state.
Although the above-described position adjusting mechanism is applied to the drum brake device 25 on the rear wheel 15 side in each of the embodiments, the drum brake device 25 ′ on the front wheel 9 side in the second embodiment is described. It can also be applied to. Since the configuration in that case is the same as the above-described position adjustment mechanism, detailed description and drawings are omitted.

(Fourth embodiment)
Next, as an embodiment according to the present invention other than the above-described embodiments and modifications, a fourth embodiment will be described in detail below with reference to FIGS. In these drawings, members and parts that are the same as or equivalent to those described in the above-described embodiments and modifications are given the same reference numerals, and detailed descriptions thereof are omitted. Differences from the embodiment and the modification will be mainly described in detail. Also in this embodiment, it is needless to say that the same operations and effects can be achieved with the same or equivalent configurations as the above-described embodiments and modifications.
FIG. 16 is a diagram showing a portion including the rear-wheel drum brake device and its vicinity in the vehicle brake device according to the fourth embodiment, and is a diagram referred to in the description of the third embodiment. 11 is a diagram corresponding to FIG.
FIG. 21 shows the relationship between the amount of movement of the pin 71 that moves together with the connecting rod 67 and the rotation angle when the guide member 47 rotates around the axis of the pin 71 along with the movement. is there. In the drawing, the horizontal axis represents the amount of movement of the pin 71 from the reference position (position before the brake pedal 53 is depressed), and the vertical axis represents the reference angle position of the guide member 47 (angular position before the brake pedal 53 is depressed). ) (The rotation angle around the axis of the pin 71). In detail, the small circles filled in black in the figure are the rotation angles corresponding to the amount of movement, and the straight line between the circles is simply a straight line between the circles. It is a tie.

The drum brake device 25 according to the fourth embodiment employs the same cam mechanism 111 as the drum brake device 25 according to the third embodiment described above, and is similar to the modification shown in FIG. 15 described above. The position adjustment mechanism is adopted.
The cam mechanism 111 according to the fourth embodiment will be described in detail. The cross-sectional shape of the pin 113 is formed in a semicircular shape having a flat lower surface, while the cam portion 115 of the guide member 47 has a contour shape. A sudden change portion 115a in which a part of the change is suddenly changed, and a non-change portion 115b having a flat upper surface continuous to the sudden change portion 115a without sudden change is formed. For this reason, when the guide member 47 rotates about the axis of the pin 71 by the action of the cam mechanism 111 based on the movement of the pin 71, the rotation of the guide member 47 is performed while the pin 71 moves forward by the unit movement amount. When the amount of change in the moving angle is defined as the angle change degree, the angle change degree suddenly changes when the pin 113 relatively moves on the sudden change portion 115a of the cam portion 115. The slope of each straight line connecting the black circles shown in FIG. 21 represents the angle change, and the steeper the slope, the greater the angle change. The pin 113 constitutes a “contact member” in the present invention.
On the other hand, when the pin 113 moves relative to the unchanged portion 115b of the cam portion 115, the angle change degree is configured to be 0 or near 0. The sudden change portion 115a and the non-change portion 115b of the cam portion 115 constitute the “first region” and the “second region” in the present invention, respectively.

One end of a C-shaped connecting member 131 is inserted into a through hole 129 (see an enlarged view of FIG. 17) formed in the vicinity of the pin 71 connected to the guide member 47 and the cam portion 115 of the guide member 47. Is inserted in a rotatable manner, and one end of the spring member 49 is hooked on the other end of the connecting member 131. The other end portion of the spring member 49 is hooked in a through hole formed in the tip end portion 127b of the adjustment rod 127 formed in a tapered shape. The connecting member 131, the spring member 49, and the adjustment rod 127 to which the spring member 49 is connected constitute the “spring means” and the “first operating force transmission member” in the present invention.
Since the through hole 129 where the tensile force of the spring member 49 acts on the guide member 47 is disposed in the vicinity of the pin 71, the connecting member 131 and the pin 119 of the brake rod 45 approach each other. Therefore, as shown in FIG. 20B, the connecting member 131 has an inner width W1 larger than the total length W2 of the pin 119, and when the brake pedal 53 is depressed, the connecting member 131 and the pin 119 Are relatively displaced so that they do not come into contact with each other even if they overlap when viewed from the side as shown in FIG. 18 (2).
A cylindrical member 125a is fixed by welding to a base portion 125 formed by protruding the body of the cam lever 43 in the middle in the longitudinal direction of the cam lever 43, and the adjustment rod 127 is inserted into the through hole of the cylindrical member 125a. A midway portion in the longitudinal direction is inserted so as to be relatively movable, and a nut 133 with a locking mechanism is screwed into the male screw portion 127a of the adjustment rod 127. The tensile force of the spring member 49 can be adjusted by appropriately adjusting the screwing position of the nut 133 with respect to the male screw portion 127a.

A coiled spring member 135 is inserted in the outer periphery of the brake rod 45 in the longitudinal direction, and the brake rod 45 is pulled out from the through hole of the rotating shaft 44 by the spring force in the extending direction of the spring member 135. The brake rod 45 is always energized. As a result, the main nut 75 is engaged with the concave surface of the front end surface of the main nut 75 in a state where a part of the outer peripheral surface of the rotating shaft 44 is in pressure contact, so that the main nut 75 does not rotate and drop off with respect to the brake rod 45. Yes.
In addition, one end 123 a of the torsion spring 123 having a midway portion in the longitudinal direction wound around the rotation shaft 44 extends rearward from the wound portion and is hooked on the outer peripheral portion of the main nut 75. On the other hand, the other end 123b of the torsion spring 123 extends upward from the wound portion, the extended portion is bent, and the bent portion is the cam lever 43 (rotating shaft). 44 is inserted through a through hole drilled in a portion located in the vicinity of 44. The torsion spring 123 is applied with an initial load that urges the one end portion 123a and the other end portion 123b away from each other. As a result, the brake rod 45 is always urged by the torsion spring 123 so that the outer peripheral surface of the pin 119 contacts the upper edge of the guide portion 73 of the guide member 47.
Furthermore, circumferential groove portions are formed at both ends of the pin 119 of the brake rod 45 inserted into the guide portion 73 of the guide member 47, and a pair of circlips 137, 137 are formed in these groove portions. Each is attached. This prevents the pin 119 from coming out of the guide portion 73 of the guide member 47 and the clamping portion 45b of the brake rod 45.

<Operation of brake device>
Next, an example of the operation of the brake device according to the fourth embodiment will be described with reference to FIG. The operation of the brake is performed as described in <Operation of the brake device> in the first embodiment described above. FIG. 17 (1) is a view corresponding to FIG. 12 (1) described above. When the brake pedal 53 is started to be depressed (time t1 in FIG. 4 (1) and FIG. 2 (2)), While the brake shoe 51 of the drum brake device 25 and the brake drum 33 approach each other, the pin 119 of the brake rod 45 is located at a portion other than the engaging portion 73 a of the guide portion 73 of the guide member 47. . FIG. 21 shows the movement amount of the pin 71 in this state as λ1 and the rotation angle of the guide member 47 as θ1. In this state, the cam lever 43 is rotated only by the tensile force of the spring member 49, and when viewed from the direction along the axis of the axle 37, the axis of the pin 71 is placed on an imaginary straight line L 1 passing through the center of the spring member 49. The wick is located.

  Further, when the depression load FP of the brake pedal 53 is increased, the operating force of the brake pedal 53 is transmitted to the pin 71 via the connecting rod 67, and the pin 71 moves forward together with the guide member 47. 18 (2) shows that the pin 71 moves slightly forward compared to FIG. 17 (1) so that the upper surface of the pin 119 of the brake rod 45 contacts the upper edge of the guide portion 73 of the guide member 47. On the other hand, the rear end of the pin 113 has reached and abutted against the sudden change portion 115a of the cam portion 115 of the guide member 47. FIG. 21 shows the movement amount of the pin 71 in this state as λ2 and the rotation angle of the guide member 47 as θ2. In this state, the inner peripheral surface 33a of the brake drum 33 and the friction surface 51a of the brake shoe 51 abut. Even in this state, the cam lever 43 is rotated only by the tensile force of the spring member 49, and the shaft of the pin 71 is placed on the virtual straight line L <b> 1 passing through the center of the spring member 49 when viewed from the direction along the axis of the axle 37. The wick is located.

Further, when the depression load FP of the brake pedal 53 is increased, the pin 71 further moves forward together with the guide member 47, and the guide member 47 is moved by the cam mechanism 111 based on the movement of the pin 71. It rotates around the axis. Specifically, the guide member 47 is connected to the pin 71 by the action of the cam mechanism 111 by the rear end portion of the pin 113 moving relative to the guide member 47 along the sudden change portion 115 a of the cam portion 115 of the guide member 47. It rotates around the axis. Thereby, the rotation angle of the guide member 47 at the time of the rotation and the moving position of the pin 71 are uniformly associated. Since the contour shape of the cam portion 115 of the guide member 47 is suddenly changed by the sudden change portion 115a, the angle change degree of the guide member 47 described above changes suddenly when the pin 113 moves relative to the sudden change portion 115a.
Therefore, even if the amount of depression of the brake pedal 53 after the inner peripheral surface 33a of the brake drum 33 and the friction surface 51a of the brake shoe 51 contact each other is not excessively increased, the pin 119 of the brake rod 45 is guided by the guide member. The guide member 47 can be rotated at a rotation angle that engages with the engagement portion 73 a of 47.

  In addition, since the through hole 129, which is a position where the tensile force of the spring member 49 acts on the guide member 47 via the connecting member 131, is disposed in the vicinity of the pin 71, the tensile force of the spring member 49 acts. The point P (see FIG. 18 (3)) is also positioned in the vicinity of the pin 71. Therefore, as shown in FIG. 3 (3), the distance S between the action point P and the axis of the pin 71 (the straight line extending in the direction in which the tensile force of the spring member 49 acts and passing through the action point P and the axis of the pin 71) The shortest distance from the core can be made as small as possible. As a result, before the transition from the state (2) to the state (3) in FIG. 18, the rotational force for rotating the guide member 47 counterclockwise by the tensile force of the spring member 49 is compared. Since the guide member 47 is rotated clockwise around the axis of the pin 71 by the sliding contact between the sudden change portion 115a of the cam portion 115 and the pin 113, the pedaling force of the brake pedal 53 is excessively increased. There is no need to make it bigger.

In FIG. 18 (3), the rear end of the pin 113 is located at the end (upper end in FIG. 18) of the sudden change portion 115a of the cam portion 115. In this state, the brake rod 45 The pin 119 is engaged with the engaging portion 73 a of the guide member 47. For this reason, when the cam lever 43 is further rotated clockwise from the state shown in FIG. 3 (3), the tensile force of the brake rod 45 is exclusively used. FIG. 21 shows the movement amount of the pin 71 in the state shown in FIG. 3 as λ3 and the rotation angle of the guide member 47 as θ3.
Thus, from the state in which the pedal force is transmitted to the cam lever 43 via the spring member 49 as the pedal force increases in the process of depressing the brake pedal 53, the brake pedal 45 is exclusively transmitted to the cam lever 43 via the brake rod 45. Since it can be switched to the transmitted state with a small depression amount of the brake pedal 53 and a normal depression force, the operation feeling of the brake pedal 53 can be further improved.

  Further, when the depression load FP of the brake pedal 53 is increased, the pin 71 further moves forward together with the guide member 47, and the guide member 47 is moved by the cam mechanism 111 based on the movement of the pin 71. Further rotation around the axis. Also during this rotation, the rotation angle of the guide member 47 and the movement position of the pin 71 are uniformly related by the action of the cam mechanism 111. FIG. 19 (4) shows a state in which the rear end portion of the pin 113 is located at the front end portion of the unchanged portion 115 b of the cam portion 115. Even in this state, the state in which the pin 119 of the brake rod 45 is engaged with the engaging portion 73a of the guide member 47 is maintained, and the force for rotating the cam lever 43 clockwise in FIG. It depends on the tensile force of the rod 45. In this state, as shown in FIG. 4 (4), the shafts of the pin 71, the pin 119, and the rotating shaft 44 are located on a substantially straight line when viewed from the side. FIG. 21 shows the movement amount of the pin 71 in this state as λ4 and the rotation angle of the guide member 47 as θ4. At this time, the distance S between the axis of the pin 71 and the operating point P of the spring member 49 is slightly larger than the state shown in FIG. The rotational force that rotates the guide member 47 counterclockwise of the core is slightly increased from the state shown in FIG. However, as the state shown in FIG. 3 (3) shifts to the state shown in FIG. 19 (4), the tensile force by the brake rod 45 increases rapidly, and the tensile force is the tensile force of the spring member 49. It is much larger than For this reason, the rotational angle position of the guide member 47 around the axis of the pin 71 is determined solely by the direction of the tensile force of the brake rod 45, so that the guide member 47 is driven by the tensile force of the spring member 49. It does not turn around undesirably.

  Further, when the depression load FP of the brake pedal 53 is increased, the pin 71 moves a little further forward along with the guide member 47, and this state is shown in FIG. Even in this state, the axes of the pin 71, the pin 119, and the rotating shaft 44 are positioned substantially on a straight line when viewed from the side as shown in FIG. FIG. 21 shows the movement amount of the pin 71 in this state as λ5 and the rotation angle of the guide member 47 as θ5. As can be seen from FIG. 21, the rotation angle θ4 of the guide member 47 when the pin 71 moves to λ4 and the rotation angle θ5 of the guide member 47 when the pin 71 moves to λ5 are the same. It has become. The reason is that even if the pin 71 moves forward from the state shown in FIG. 19 (4) to the state shown in FIG. 19 (5), the flat lower surface of the pin 113 of the cam mechanism 111, This is because the guide member 47 only moves in parallel with little rotation, since it moves relative to the flat upper surface of the unchanged portion 115b of the cam portion 115 while maintaining a state substantially parallel to each other. For this reason, the pin 113 and the cam portion 115 of the cam mechanism 111 slide relative to each other when the cam lever is rotated by the tensile force of the brake rod to generate the braking force of the drum brake device in earnest. The pedal force of the brake pedal 53 is not used unnecessarily as the frictional force or the rotational force that rotates the guide member 47. As a result, the depression force of the brake pedal 53 is effectively used to generate the braking force of the drum brake device 25.

On the other hand, if the stepping load FP of the brake pedal 53 is reduced to zero, a spring member (not shown) that urges the inner peripheral surface 33a of the brake drum 33 and the friction surface 51a of the brake shoe 51 to separate. ) And the repulsive force of the spring member 85 cause the connecting rod 67 and the pin 71 to move rearward. Then, the process proceeds in reverse order from the state shown in FIG. 19 (5) to the state shown in FIG. 17 (1) through the states shown in FIG.
Above, the description regarding the action | operation of the brake device which concerns on 4th Embodiment is complete | finished.
The configuration of the drum brake device 25 according to the fourth embodiment described above can also be applied to the drum brake device 25 ′ on the front wheel 9 side in the second embodiment. Needless to say, the configuration of the drum brake device 25 ′ after the application is the same as that of the drum brake device 25 according to the above-described fourth embodiment, and thus detailed description and drawings are omitted.

1 vehicle 1 'vehicle 9 front wheel 15 rear wheel 21 brake disc plate (front wheel braking device)
23 Brake caliper (front wheel braking device)
25 Drum brake device (rear wheel brake device)
25 'drum brake device (front wheel braking device)
35 Brake drum 35a Inner peripheral surface 41 Cam shaft 43 Cam lever 45 Brake rod (second operating force transmission member)
47 Guide member (operation force transmission member)
49 Spring member (spring means, first operating force transmission member)
51a Friction surface 51 Brake shoe 53 Brake pedal (brake operator)
59 Equalizer (operating force transmission means, connection means)
63 Link member (operation force transmission means, connection means)
67 Connecting rod (operating force transmission means, connecting means)
71 pin (rotating shaft)
73 Guide part 73a Engagement part 87 1st brake wire (operation force transmission means, connection means)
89 Relay device (operation force transmission means, connection means)
91 Second brake wire (operation force transmission means, connection means)
111 Cam mechanism 113 Pin (contact member)
115 Cam portion 115a Sudden change portion (first region)
115b Unchanged part (second region)
123 Torsion spring (spring mechanism)
127 Adjustment rod (spring means, first operating force transmission member)
131 connecting member (spring means, first operating force transmission member)

Claims (11)

At least one of the front wheel braking device that brakes the front wheel and the rear wheel braking device that brakes the rear wheel is configured by a drum brake device, and both the braking devices are operated simultaneously by operating one brake operator. In the vehicle brake device,
The drum brake device includes an annular brake drum, a brake shoe having a friction surface slidable on an inner peripheral surface of the brake drum, a cam shaft for expanding the brake shoe, and one end portion on the cam shaft. And a cam lever that rotates the cam shaft around its axis,
An operation force of the brake operator is transmitted to the cam lever via an operation force transmission means to rotate the cam lever,
The operating force transmitting means includes a first operating force transmitting member that transmits the operating force to the first operating point of the cam lever when the operating force of the brake operator starts to be applied, and the applied brake. A second operating force transmission member that exclusively transmits the operating force to the second action point of the cam lever as the operating force of the operator increases.
The vehicle braking device according to claim 1, wherein the second action point is positioned at a position spaced apart from the first action point with respect to an axis of the cam shaft. The vehicle brake device according to claim 1,
The operating force transmission means further includes a connection means and a guide member connected to the brake operator via the connection means,
The first operating force transmission member is constituted by a spring means, while the second operating force transmission member is constituted by a brake rod,
One end of the spring means is rotatably connected to the first operating point of the cam lever, and the other end of the spring means is rotatably connected to the guide member,
One end of the brake rod is rotatably connected to the second operating point of the cam lever, and the other end of the brake rod is connected to the guide member so as to be relatively movable. It moves along the guide part formed in the guide member,
The guide part has an engaging part that can engage the other end part of the brake rod, and a non-engaging part excluding the engaging part,
As the operating force increases in the process of operating the brake operator, the other end of the brake rod moves from the non-engagement portion of the guide portion toward the engagement portion and moves to the engagement portion. Configured to engage,
When the other end portion of the brake rod is positioned at the non-engaging portion of the guide portion, the operating force of the brake operator is transmitted to the cam lever via the spring means,
When the other end portion of the brake rod is engaged with the engaging portion of the guide portion, as the operating force of the brake operator increases, the operating force is exclusively transmitted through the brake rod. A vehicle brake device configured to be transmitted to a cam lever. The vehicle brake device according to claim 2,
The brake device of a vehicle, wherein the brake rod is always urged by a spring mechanism so that the other end portion of the brake rod comes into contact with the guide portion. In the brake device of the vehicle according to claim 2 or 3,
The guide member is rotatably connected to the connecting means via a rotation shaft,
The rotating shaft moves together with the guide member by the operation force of the brake operator being transmitted through the connecting means,
When the guide member rotates about the axis of the rotation shaft by the action of the cam mechanism based on the movement of the rotation shaft, the rotation angle of the guide member and the rotation shaft when the guide member rotates. The vehicle brake device is configured to be uniformly associated with the movement position of the vehicle. The vehicle brake device according to claim 4,
The vehicular brake device according to claim 1, wherein a connecting portion where the other end portion of the spring means is connected to the guide member is positioned in the vicinity of the rotating shaft. The vehicle brake device according to claim 4 or 5, wherein:
The cam mechanism includes a cam portion formed on the guide member, and an abutting member that can move relative to the guide member along the cam portion as the rotation shaft moves. A vehicle brake device characterized by the above. The vehicle brake device according to claim 6,
In the case where the guide member is rotated around the axis of the rotation shaft by the action of the cam mechanism based on the movement of the rotation shaft, the guide member is moved while the rotation shaft is moved by a unit movement amount. When the amount of change in the rotation angle is defined as the degree of angle change,
In the region of the cam portion in which the contact member relatively moves, a first region in which the angle change degree is suddenly changed and a second region in which the angle change degree is 0 or in the vicinity of 0 are provided,
As the operating force of the brake operator increases, the abutting member relatively moves from the first region of the cam portion toward the second region,
When the abutting member relatively moves in the first region toward the second region, the other end portion of the brake rod disengages the non-engaging portion of the guide portion, and the guide portion Engaging with the engaging portion of
When the abutment member is relatively moving in the second region of the cam portion, the state where the other end portion of the brake rod is engaged with the engagement portion of the guide portion is maintained. A brake device for a vehicle, characterized in that it is configured. The vehicle brake device according to any one of claims 2 to 7,
The guide portion of the guide member is formed of a long hole, and the engagement portion is formed at one end portion or midway portion in the longitudinal direction of the guide portion,
The vehicle brake device, wherein the guide member is connected to the other end portion in a state where the other end portion of the brake rod is inserted into the guide portion. The vehicle brake device according to any one of claims 2 to 8,
When the other end portion of the brake rod is engaged with the engaging portion of the guide portion, the engagement state is held by the action of a tensile force applied to the guide member by the spring means. A brake device for a vehicle. The vehicle brake device according to any one of claims 2 to 9,
The vehicle brake device further comprises a position adjusting mechanism capable of adjusting a position of the first action point where one end of the spring means is connected to the cam lever.   A vehicle equipped with the vehicle brake device according to any one of claims 1 to 10.

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