JP2011085573A - Device for detecting pedal force of vehicle - Google Patents

Abstract

In a vehicle treading force detection device for transmitting rotation of a crankshaft 9 to a rear wheel WR with a chain 12, treading force detection is performed without impairing the direct feeling that the treading force input to the crankshaft 9 is directly transmitted to the rear wheel WR. Provided is a pedaling force detection device capable of obtaining an output.
A chain 12 is bridged between a crank sprocket 13 coupled to a crankshaft 9, a resultant sprocket 14 driven by a motor 11, and a rear wheel sprocket 16. Of the bearings 27 and 28 that support the crankshaft 9, the inner diameter of the bearing housing recess 35 that houses the bearing 28 on the crank sprocket 13 side is made slightly larger than the outer diameter of the bearing 28. A hydraulic sensor 36 having a piston 38 that comes into contact with the outer peripheral surface of the bearing 28 from the rear of the vehicle body and a hydraulic chamber 42 provided between the piston 38 and the sensor pressure receiving portion 76 is provided.
[Selection] Figure 4

Description

  The present invention relates to a pedaling force detection device, and more particularly to a pedaling force detection device for a vehicle that detects the magnitude of a pedaling force that rotates a sprocket coupled to a crankshaft of a two-wheeled vehicle.

  2. Description of the Related Art A bicycle with a driving assist device is known in which a pedaling force applied to a crankshaft is detected and an electric assisting force corresponding to the pedaling force is applied to driving wheels to assist human power. In this bicycle with a driving assist device, an appropriate assisting force can be generated by accurately detecting the magnitude of the pedaling force applied to the crankshaft, and therefore various pedaling force detection devices have been considered.

  For example, Patent Document 1 is a bicycle treading force detection device that includes a mechanical support between an inner periphery of a support portion of a crankshaft, an outer periphery of a bearing that supports the crankshaft, and an inner periphery of a support portion that supports the bearing. There has been proposed a treading force detection device that includes a sensor sleeve that incorporates a sensor chip having a characteristic that an electric resistance changes in accordance with strain, and detects a driving torque in a direction opposite to a driving force acting on a bicycle.

JP-A-11-258078

  In the pedaling force detection device described in Patent Document 1, a sensor sleeve containing a sensor chip (distortion sensor) is disposed between a bearing and a bearing support provided on the vehicle body frame. Variations in the gap between parts caused by manufacturing errors (tolerances) and the like due to aging degradation cause variations in the pedal force applied to the sensor chip, and it is necessary to deal with such variations.

In addition, since the pedal force acts directly on the sensor chip, it is necessary to consider the impact load on the sensor chip and to meet the demand for higher durability.
The object of the present invention is to solve the above problems by solving a gap in the sensor device due to manufacturing errors and aging deterioration at a relatively low cost, and to provide a pedal depression force detection structure that is excellent in impact resistance load and durability to the sensor. It is to provide.

  To achieve the above object, the present invention provides a crankshaft that is rotated by a pedaling force input to a pedal crank, a bearing that supports the crankshaft at two points, and a crank sprocket and a rear wheel sprocket coupled to the crankshaft. In a bicycle treading force detection device having a chain that is bridged, one of the bearings is disposed with a gap with respect to the vehicle body frame, and a bearing that is disposed with the gap provided by pedaling of a pedal crank is provided. The piston is configured to be movable within the range of the gap, and is disposed in contact with the outer periphery of the bearing arranged with the gap, and is displaced according to the movement of the bearing, and the non-pressurized and depressurized by the piston. A first feature is that it includes a fluid pressure chamber that accommodates a compressed fluid, and a fluid pressure sensor that outputs a pedal effort according to the pressure in the fluid pressure chamber. .

Further, the present invention provides the bearing housing so that a gap is formed at least on the vehicle body rear side between the outer peripheral surface of the bearing on the crank sprocket side of the bearing and the bearing housing recess for housing the bearing. The second feature is that the dimension of the recess is determined.
In addition, the present invention has a third feature in that, among the plurality of bearings, a bearing far from the crank sprocket is a self-aligning bearing.

  The present invention also provides a bearing that supports a crankshaft that rotates with a pedaling force input to a pedal crank at two points, a crank sprocket coupled to the crankshaft, and a chain spanned between the crank sprocket and the rear wheel sprocket. In the pedal effort detection device for a bicycle with a drive assisting machine, a bearing box that houses a bearing that supports a side of the bearing far from the crank sprocket side, and a side of the bearing that is close to the crank sprocket side. A second bearing housing that houses a bearing to be supported, a cylindrical holder that holds the outer periphery of the bearing housing and the second bearing housing, and a non-compressed portion that transmits the displacement of the fluid pressure piston and the fluid pressure piston to the pressure receiving portion. A fluid pressure sensor having a fluid pressure chamber containing a natural fluid, and the second bearing box is displaceable with respect to the cylindrical holder. And a portion projecting from the cylindrical holder toward the crank sprocket side, wherein the piston of the fluid pressure sensor is the projecting portion of the second bearing box. There is a fourth feature in that it is disposed in contact with each other.

  Further, the present invention has a fifth feature in that the rear wheel sprocket is driven by a pedaling force input to the crankshaft and an output of a power unit provided in a hub of the rear wheel.

  In the present invention, the piston of the fluid pressure sensor, the pressure receiving portion, the fluid pressure chamber, and the sensor main body connected to the fluid pressure chamber are arranged in a line, and the alignment direction is set along the longitudinal direction of the vehicle body. There is a sixth feature.

  The present invention also provides a crankshaft that is rotated by a pedaling force input to a pedal crank, a resultant force shaft that is coupled to the crankshaft via a gear pair, a motor as a drive assist device, and rotation of an output shaft of the motor. A reduction gear that decelerates and connects to the resultant force shaft, a power unit output shaft that guides the rotation of the resultant force shaft to the outside, a drive side sprocket coupled to the power unit output shaft, and between the drive side sprocket and the driven side sprocket In the treading force detection device for a vehicle having a chain stretched over, the gear pair is constituted by a helical gear, and the resultant force shaft can be displaced by a predetermined amount by thrust generated in the gear pair by rotation of the crankshaft. The resultant force shaft is supported by a bearing and arranged in contact with the end of the resultant force shaft, and is displaced according to the displacement of the resultant force shaft by the thrust. There are seventh feature in that and a fluid pressure sensor having a fluid pressure chamber containing a non-compressible fluid which transmits the piston and displacement of the piston to the pressure receiving portion that.

  Furthermore, the present invention has an eighth feature in that a relief device is provided for discharging the fluid in the fluid pressure chamber from the fluid pressure chamber when the hydraulic pressure in the fluid pressure chamber becomes an excessive pressure equal to or higher than a predetermined value. There is.

  Further, the present invention provides a pedaling force detection device having a crank sprocket that transmits a manual torque applied to a pedal crankshaft to a rear wheel by a drive chain, and a torque detection means that detects the manual torque applied to the pedal crankshaft. A piston provided to be displaceable in the longitudinal direction of the pedal crankshaft, a rear wheel load provided on a side portion of the crank sprocket and driven by the crank sprocket, and a human torque applied to the pedal crankshaft. A mechanism for displacing the piston in the longitudinal direction of the pedal crankshaft by a difference between the hydraulic pressure chamber and a hydraulic chamber in which an internal hydraulic pressure changes according to the displacement of the piston, and the torque detecting means is connected to the hydraulic chamber, It is configured to detect the hydraulic pressure of the hydraulic chamber as information representative of the human power torque. 9 there is a feature of.

  The torque detecting means has a tenth feature in that the longitudinal direction of the torque detecting means is arranged in the vehicle width direction.

  According to the present invention having the first and fourth features, the bearing of the crankshaft is disposed with a gap between it and the vehicle body frame, so that the bearing is displaced in the gap by the pedaling force generated during pedaling. The displacement of the bearing is transmitted to the piston, and the displacement of the piston is transmitted to the sensor via an incompressible fluid such as oil. Therefore, fluctuations in the gaps between the parts caused by manufacturing errors of parts of the pedal force detection device and aging deterioration are absorbed by the gaps provided in advance. Further, since the degree to which the impact load at the time of pedaling affects the fluid pressure sensor is reduced, durability can be improved.

  In addition, since the pedaling force is applied to the incompressible fluid, the influence of the frictional resistance on the crankshaft can be reduced, and there is no lost motion during pedaling in the conventional device using a strain sensor. It is possible to prevent the user from feeling uncomfortable during pedaling.

  According to the present invention having the second feature, by providing a gap between the bearing of the crankshaft and the bearing housing recess, the bearing is allowed to displace, and the pedaling force can be detected based on this displacement. .

  According to the present invention having the third feature, the side of the crankshaft to which the crank sprocket is coupled can be easily displaced around the self-aligning bearing.

  According to the present invention having the fifth feature, since the power unit is not provided around the crankshaft, the bearing box and the second bearing box are supported in the cylindrical holder, and the hydraulic sensor is connected to the cylindrical holder. The treading force detection device can be easily incorporated into an existing vehicle by simply changing the attachment to the vehicle.

  According to the present invention having the sixth feature, the fluid pressure sensor can be accommodated in an elongated space extending in the front-rear direction of the vehicle body.

  According to the present invention having the seventh characteristic, when the rotation of the crankshaft is transmitted to the resultant force shaft via the helical gear, a thrust is generated on the resultant force shaft, and the thrust is a fluid pressure sensor as a force representing the pedaling force. Is detected. Since the thrust is smaller than the force that causes the crankshaft to be displaced rearward by the reaction force of the chain tension, the fluid pressure sensor can be reduced in size.

  According to the present invention having the eighth feature, when an excessive pressure is applied to the fluid pressure sensor due to an impact load or the like, the pressure in the fluid pressure chamber is reduced to protect the fluid pressure sensor and improve its durability. be able to.

  According to the present invention having the ninth feature, since the piston is provided to be displaceable in the longitudinal direction of the pedal crankshaft, the piston can be expanded around the pedal crankshaft, and the piston diameter is increased. be able to. Therefore, a sensor corresponding to a relatively low oil pressure can be used as the torque detection means, and the cost can be reduced. Moreover, the mechanism for displacing the piston in the longitudinal direction of the pedal crankshaft is provided on the side of the crank sprocket, so that the manual torque can be applied without changing the vehicle body frame structure including the crank hub mechanism provided in the existing bicycle. (Stepping force) can be detected.

  According to the present invention having the tenth feature, the dead space in the portion along the longitudinal direction (axial direction) of the pedal crankshaft can be effectively utilized, so that an efficient layout is possible.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a left side view of a bicycle with a drive accessory having a pedaling force detection device according to a first embodiment of the present invention. It is a principal part enlarged view of the bicycle described in FIG. FIG. 2 is a plan sectional view of the power unit of the bicycle described in FIG. 1. It is a principal part expanded sectional view of the power unit shown in FIG. It is an expanded sectional view of the pedal effort detector concerning a 1st embodiment. It is a left view of the bicycle with a drive auxiliary machine which has the treading force detection apparatus which concerns on 2nd Embodiment of this invention. It is principal part plane sectional drawing of the bicycle with a drive auxiliary machine containing the treading force detection apparatus which concerns on 2nd Embodiment. It is sectional drawing of the power unit provided in the rear-wheel of the bicycle with a drive auxiliary machine containing the treading force detection apparatus which concerns on 2nd Embodiment. It is a left view of the bicycle with a drive auxiliary machine containing the treading force detection apparatus which concerns on 3rd Embodiment of this invention. It is a schematic diagram which shows the gear arrangement | sequence of the power unit containing the treading force detection apparatus in 3rd Embodiment. It is AA arrow sectional drawing in FIG. It is BB arrow sectional drawing in FIG. It is a principal part enlarged view of the power unit shown in FIG. It is a left view of the bicycle with a drive auxiliary machine containing the treading force detection apparatus which concerns on 4th Embodiment of this invention. It is CC sectional view taken on the line in FIG. It is a principal part enlarged view of FIG. It is a principal part enlarged view of FIG. 16 which shows a hydraulic sensor protection mechanism.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a left side view of a bicycle with a drive assisting device provided with a pedaling force detection device according to an embodiment of the present invention, and FIG. 2 is an enlarged view of the main part. 1 and 2, a body frame of a bicycle with a drive assist device (hereinafter simply referred to as “bicycle”) 1 includes a head pipe 2, a main pipe 3, a standing pipe 4, a seat stay 5, and a chain stay 6. Is provided. The rear end portion of the main pipe 3 and the lower end portion of the standing pipe 4 are joined to a bracket 7, and the bracket 7 is coupled to a power unit 8, which will be described in detail later, with bolts. The front end of the chain stay 6 is connected to the rear upper part of the power unit 8. The front end portion of the seat stay 5 is connected to the standing pipe 4, and the rear end portion of the seat stay 5 is connected to the rear end portion of the chain stay 6 to constitute a support portion for the rear wheel WR.

  A vehicle body left crank 10L and a vehicle body right crank 10R having pedals are connected to both ends of the crankshaft 9 supported by the power unit 8, respectively. A drive chain (hereinafter simply referred to as “chain”) 12 that transmits the driving force of the crankshaft 9 supported by the power unit 8 and the motor 11 to the rear wheel WR includes a crank sprocket 13, a resultant sprocket 14, an idle sprocket 15, and It is stretched over the rear wheel sprocket 16. A chain cover 17 is provided above the chain 12. In the power unit 8, a pedaling force detection unit 18 is disposed on the vehicle body rear side of the crankshaft 9.

  The rear wheel WR is provided with a rear wheel mudguard 19, and a battery unit 20 serving as a power source for the power unit 8, a controller 21, and a space between the front part of the rear wheel mudguard 19 and the standing pipe 4 Is placed.

  A steering shaft 22 extends vertically through the head pipe 2, and a steering handle 23 extending in the lateral direction of the vehicle width is coupled to the upper portion of the steering shaft 22. Below the head pipe 2, the upper end of the front fork 24 is coupled to the lower end of the steering shaft 22, and the front wheel WF is rotatably supported on the lower end of the front fork 24 by the front wheel shaft 25.

  FIG. 3 is a plan sectional view of the power unit, and FIG. 4 is an enlarged view of a main part of FIG. 3 and 4, the power unit 8 includes a case 26 including a central case portion 81, a vehicle body left side case portion 82, and a vehicle body right side case portion 83. The crankshaft 9 is rotatably supported by ball bearings 27 and 28 fixed to the vehicle body left case portion 82 and the vehicle body right case portion 83 at the front portion (left side portion in the figure) of the case 26. The bearing 27 is preferably a self-aligning ball bearing in which the inner ring has two rows of tracks and the outer ring has a spherical surface. A dust seal 29 is provided between the bearing 27 and the crankshaft 9, and a dust seal 30 is provided between the bearing 28 and the crankshaft 9. An O-ring 31 is provided between the outer periphery of the bearing 28 and the vehicle body right side case portion 83.

  Cranks 10 </ b> L and 10 </ b> R are coupled to protruding portions of the crankshaft 9 protruding from the case 26 on both sides of the vehicle body. A crank sprocket 13 is coupled to the crankshaft 9 via a ratchet one-way 32 between the crank 10R on the right side of the vehicle body and the bearing 28. The ratchet one-way 32 includes an inner ring 32a, a claw portion 32b, and an outer ring 32c coupled to the crankshaft 9 by spline engagement, and the outer ring 32c and the crank sprocket 13 are coupled by a rivet 33. The crank sprocket 13 and the outer ring 32 c are provided to be rotatable with respect to the outer periphery of the inner ring 32 a via a bearing 34. Only rotation in one direction of the crankshaft 9 (rotation in the direction in which the vehicle body is propelled by the rear wheel WR) is transmitted from the inner ring 32a to the outer ring 32c via the claw portion 32b, and the crank sprocket 13 is driven.

  The inner diameter of the bearing receiving recess 35 formed in the vehicle body right side case 83 for receiving the bearing 28 is formed slightly larger than the outer diameter of the bearing 28 or the rear side of the vehicle body is shaved, so that the outer peripheral surface of the bearing 28 is The bearing 28 is accommodated in the bearing accommodating recess 35 with a gap formed between the inner periphery of the recess 35. Accordingly, the bearing 28 is displaceable by a minute dimension at least toward the rear of the vehicle body with the alignment center 27a of the bearing 27 as the center.

  The vehicle body right side case 83 is formed with a sensor housing recess 37 for housing the hydraulic sensor 36 that is an element of the pedaling force detection unit 18. The hydraulic sensor 36 includes a piston 38 that can be displaced in the longitudinal direction of the recess 37, a coil spring 39 that acts to bias the piston 38 toward the bearing 28, and a sensor body 40. The piston 38 includes an O-ring 41 that maintains fluid tightness with the inner peripheral surface of the sensor housing recess 37, and the tip small-diameter portion 38 a of the piston 38 passes through a hole formed in the bottom of the sensor housing recess 37. In contact with the outer peripheral surface of the bearing 28. The coil spring 39 is disposed in a hydraulic chamber 42 formed between the sensor body 40 and the piston 38. The hydraulic chamber 42 communicates with an oil reservoir of an oil reservoir described later. In a state where the piston 38 is urged toward the bearing 28, a gap G is generated between the outer peripheral surface of the bearing 28 and the vehicle body right side case 83 forming the sensor housing recess 37. The sensor body 40 is held on the vehicle body right side case portion 83 by a stop ring 43 provided between the sensor main body 40 and the sensor housing recess 37. As described above, the hydraulic sensor 36 includes the piston 41 that contacts the bearing 28, the coil spring 39, and the sensor main body 40 that are aligned in the front-rear direction of the vehicle body perpendicular to the crankshaft 9. With such an arrangement, the hydraulic sensor 36 can be easily arranged in the space between the case 26 and the crank sprocket 13.

  Between the bearings 27 and 28, a projection 9a is formed on the crankshaft 9 at a predetermined interval in the rotation direction. The projection 9a is disposed opposite to the position where the projection 9a is formed. A sensor 44 is arranged. The rotation speed sensor 44 is disposed through the front wall of the vehicle body left side case portion 82, and is fixed to the vehicle body left side case portion 82 using a bolt 45.

  The motor 11 disposed behind the vehicle body with respect to the crankshaft 9 includes a rotor 46, a stator 47, and a motor shaft 48. The motor shaft 48 is supported by a bearing 49 held by the central case portion 81 and a bearing 50 held by the vehicle body left side case portion 82, and the rotor 46 is spline-engaged with the motor shaft 48, for example. The stator 47 includes a stator coil 51 and is fixed to the central case portion 81 with bolts 52.

  A pinion 53 is provided at one end (right side of the vehicle body) of the motor shaft 48. A reduction shaft 55 having an intermediate gear 54 that meshes with the pinion 53 is supported by the center case portion 81 and the vehicle body right side case portion 83 by bearings 56 and 57. A reduction gear 58 having a diameter smaller than that of the intermediate gear 54 is fixed to the reduction shaft 55, and an output shaft 60 having a final gear 59 meshing with the reduction gear 58 is connected to the central case portion 81 and the vehicle body by bearings 61 and 62. It is supported by the right case portion 83. The resultant sprocket 14 is coupled to the end of the output shaft 60.

  An idle shaft (bolt) 63 is erected on the vehicle body right side case portion 83, and the idle sprocket 15 is rotatably supported by the bolt 63 via a bearing 64. The crank sprocket 13, the resultant sprocket 14, the idle sprocket 15, and the rear wheel sprocket 16 shown in FIGS. 1 and 2 are aligned in a row in plan view.

  In the configuration of the power unit 8, when the cranks 10 </ b> L and 10 </ b> R are rotated by stepping on the pedal, the crank sprocket 13 rotates and the rotation of the crank sprocket 13 is transmitted to the rear wheel sprocket 16 by the chain 12.

  Further, a pedaling force input to the crankshaft 9 (a force for rotating the crankshaft 9) is detected by the pedaling force detection unit 18, and the motor 11 is driven with a current (or energization duty) set in advance according to the detected pedaling force. Driven. Then, the rotation of the rotor 46 is transmitted to the resultant pinion 14 through the pinion 53, the intermediate gear 54, the reduction gear 58, and the final gear 59. As a result, in the chain 12, the pedaling force by human power and the driving force (auxiliary power) by the motor 11 are transmitted to the rear wheel sprocket 16, so that the bicycle can run with a small pedaling force.

  Note that the bicycle 1 with a drive assisting device is not limited to driving the motor 11 in accordance with the pedaling force, and can be configured to drive the rear wheels only with the motor 11 when no pedaling force is input. That is, it may be a hybrid bicycle that drives the rear wheels by combining human power and motor driving force individually or both.

  FIG. 5 is an enlarged cross-sectional view of the pedaling force detection unit 18. In FIG. 5, an oil reservoir 65 is further formed orthogonal to the sensor housing recess 37 in the vehicle body right side case portion 83 in which the sensor housing recess 37 is formed. The oil reservoir 65 has an oil reservoir 67 that is communicated with the hydraulic chamber 42 on the hydraulic sensor 36 side via a passage 66. A check valve 68 is screwed into the passage 66. The check valve 68 includes a housing 69, a valve body 70, a spring 71 that biases the valve body 70 downward in the drawing, a check ball 72 below the valve body 70, and a ball holder 73. A cap 75 sealed with an O-ring 74 is screwed into the oil sump 67.

  The valve body 70 is pushed downward by a spring 71, and the lower surface (seat) of the valve body 71 is in contact with the check ball 72. The contact pressure between the valve body 71 and the check ball 72 is set so that the pressure in the hydraulic chamber 42 is substantially the same as the upper limit value of the detection pressure range of the hydraulic sensor 36. Therefore, at the normal pressure within the detection range, the contact between the valve body 71 and the check ball 72 is maintained, but the pressure in the hydraulic chamber 42 becomes large so as to exceed the detection range due to an impact load or the like. When this happens, the valve body 71 is pushed up against the force of the spring 71 by the increased oil pressure, a gap is created between the seat of the valve body 71 and the check ball 72, and the hydraulic chamber 42 is depressurized. That is, a hydraulic relief function is activated. This relief function can prevent excessive pressure from being applied to the hydraulic sensor 36 due to impact load or the like, and can greatly contribute to the improvement of the durability of the hydraulic sensor 36.

  The sensor body 40 includes a pressure receiving portion 76 that faces the piston 38 with the hydraulic chamber 42 interposed therebetween. An O-ring 77 is disposed between the sensor body 40 and the sensor housing recess 37, and the sensor body 40 and the sensor The space between the housing recess 37 is kept liquid-tight.

  The operation of the pedaling force detection unit 18 is as follows. When a pedaling force is applied to the crankshaft 9, tension is applied to the chain 12, and the reaction force (chain reaction force) tends to displace the bearing 28 to the right inner wall side, that is, the piston 38 side in the bearing housing recess 35. Force (arrow 78) is generated.

  When the bearing 28 is to be displaced by the force 78, pressure is applied to the tip small diameter portion 38a of the piston 38, and the piston 38 is displaced. The displacement of the piston 38 pressurizes the incompressible oil in the hydraulic chamber 42 and the check ball 72 closes the valve body 70. The gap G is provided to ensure a stroke for the check ball 72 to be seated on the valve body 70. After the check ball 72 is seated on the valve body 70, the force 78 is transmitted to the pressure receiving portion 76 via the incompressible oil in the hydraulic chamber 42. As described above, the sensor body 40 outputs a detection signal representing the pedaling force in accordance with the force transmitted to the pressure receiving portion 76 via the piston 38. Since the bearing 27 is a self-aligning type, the bearing 28 can be easily displaced toward the piston 38 by a chain reaction force due to an increase in the treading force.

  Next, a second embodiment of the present invention will be described. The second embodiment relates to a bicycle in which a power unit is provided on the rear wheel side. FIG. 6 is a left side view showing the bicycle according to the second embodiment, and the same reference numerals as those in FIG. 1 denote the same or equivalent parts. The ends of the main pipe 3, the standing pipe 4, and the chain stay 6 of the bicycle 100 are joined to a cylindrical holder 79 that supports the crankshaft 91. A drive sprocket 84 is connected to the crankshaft 91, and a rear wheel sprocket 86 is provided on the rear wheel side. A chain 12 for transmitting the rotation of the drive sprocket 84 to the rear wheel sprocket 86 is bridged between the drive sprocket 84 and the rear wheel sprocket 86.

  A power unit 87 that provides auxiliary driving force to the rear wheel sprocket 86 is provided. The power unit 87 is pivotally supported by chain stays 6, 6 provided one on each side of the vehicle body.

  A rotational speed sensor 44 is attached to the front portion (front side portion of the vehicle body) of the cylindrical holder 79, and the treading force detection unit 18 including the hydraulic sensor 36 is attached to the rear portion (rear side portion of the vehicle body) of the cylindrical holder 79. It is done.

  FIG. 7 is a cross-sectional plan view of an essential part of the bicycle according to the second embodiment. A bearing box 89 is screwed to one end portion (left side portion of the vehicle body) of the cylindrical holder 79, and a nut 90 is screwed to the outer periphery of the bearing box 89. That is, the bearing box 89 is fixed to the cylindrical holder 79 by a double nut method. A self-aligning ball bearing 92 is accommodated in the bearing box 89.

  A second bearing box 93 is provided at the other end portion (right side portion of the vehicle body) of the cylindrical holder 79. The second bearing box 93 accommodates two bearings 94a and 94b. The second bearing box 93 has a cylindrical shape, and the outer diameter of the second bearing box 93 and the cylindrical holder 79 have a gap between the outer peripheral surface and the inner peripheral surface of the cylindrical holder 79. The inner diameter has been determined. Therefore, in order to fix the positional relationship between the bearings 94a and 94b and the crankshaft 91 (positions of the bearings 94a and 94b in the longitudinal direction of the crankshaft 91), the annular spacer 94 and the stop ring 95 are arranged. That is, the bearings 94 a and 94 b are fitted into the crankshaft 91 in order from the right side of the vehicle body, and are moved to a position where the bearing 94 a contacts the stepped portion 91 a of the crankshaft 91. Then, the spacer 94 is fitted on the crankshaft 91 and further fixed with the stop ring 96. With this structure, the position of the second bearing box 93 is fixed in the longitudinal direction of the crankshaft 91, while the displacement around the alignment center 92 a of the self-aligning ball bearing 92 is the same as that of the cylindrical holder 79. This is possible in the range of the gap G formed between the second bearing housing 89 and the second bearing housing 89. That is, in FIG. 7, the second bearing housing 93 can be displaced left and right.

  The second bearing housing 93 has a flange 93a formed at the end portion on the drive sprocket 84 side, and the hydraulic sensor 36 is disposed so that the tip end small diameter portion 38a of the piston 38 contacts the outer peripheral end surface of the flange 93a. . The hydraulic sensor 36 is housed in a sensor housing recess 37 formed in the sensor housing 36a. The sensor housing 36a having the sensor receiving recess 37 is connected to an oil reservoir (not shown) having an oil sump similar to that described with reference to FIG.

  Further, the rotation speed sensor 44 is fixed to a bracket 80 joined to the front side of the cylindrical holder 79 by using a bolt 85. The sensing surface 44a of the rotation speed sensor 44 faces the disk 97 provided on the drive sprocket 84, and the rotation speed of the disk 97 is based on the detection interval of holes 97a formed in the disk 97 at a predetermined interval. That is, the rotational speed of the crankshaft 91 is detected. For example, the rotation speed sensor 44 can be configured by a light reflection type sensor.

  In the bicycle according to the second embodiment, when the drive sprocket 84 is rotated by stepping on the pedal, the tension of the chain 12 increases, and the second bearing box 93 is displaced to the rear wheel side as described with reference to FIG. As a result, a chain reaction force is generated, and the piston 38 of the hydraulic sensor 36 is pressed. As a result, the incompressible oil in the hydraulic chamber 42 causes a pressure change in the pressure receiving portion 76 of the hydraulic sensor 36, and the hydraulic sensor 36 outputs a detection signal corresponding to the pedal effort.

  FIG. 8 is a cross-sectional view of a motor as a drive assisting device driven in accordance with a hydraulic pressure signal output from the hydraulic pressure sensor 36. In FIG. 8, a cylinder 99 incorporating a transmission is supported by a shaft 101 on a plate 98 projecting rearward from a joint portion between the rear end of the chain stay 6 and the lower end of the seat stay 5 (see FIG. 6). The shaft 101 is formed on the plate 98 and is supported in a long hole 98a that is long in the longitudinal direction of the vehicle body so that the position thereof can be adjusted in the longitudinal direction of the vehicle body. The tension of the chain 12 is adjusted by this position adjustment. Note that the position adjusting member including the adjusting bolt and the like is not a main part of the present invention and has a well-known structure, so that illustration thereof is omitted.

  A wheel hub 102 is fitted on the outer periphery of the cylinder 99. The wheel hub 102 is an annular body having an inner cylinder 102 a and an outer cylinder 102 b, and the inner peripheral surface of the inner cylinder 102 a abuts on the outer periphery of the cylinder 99. A flange 103 protruding from the cylinder 99 is fixed to the side surface of the wheel hub 102 by bolts 104. Neodymium magnets 105 constituting the rotor-side magnetic poles of the motor 130 included in the power unit 87 are arranged at a predetermined interval on the inner periphery of the outer cylinder 102 b of the wheel hub 102. That is, the outer cylinder 102 b constitutes a rotor core that holds the magnet 105.

  A cap 106 that covers the left side of the vehicle body of the cylinder 99 is fastened together with the brake base 107 to the shaft 101 with a nut 108. A bearing 109 is fitted on the outer peripheral surface of the cap 106, and the rotor cover 110 is supported by the bearing 109. The rotor cover 110 has the same outer diameter as the outer wall 102b of the wheel hub 102 and is combined with the wheel hub 102 to form a stator accommodating space of the motor 130.

  A stator support plate 111 is joined to the open side (right side in the figure) of the cap 106. The stator support plate 111 has an annular shape, and a bearing 112 is fitted on the inner periphery thereof. The bearing 112 abuts on the inner wall 102 a of the wheel hub 102 and supports the wheel hub 102. A stator 113 is attached to the stator holding support plate 111 with bolts 114. A three-phase stator coil 113a is wound around the stator 113.

  The rotor cover 110 has an annular wall 115 protruding toward the left side of the vehicle body (the lower side in the figure). A friction plate 116 is attached to the inner peripheral surface of the annular wall 115. The brake base 107 includes a brake shaft 118, a brake shoe (only the hub 119 is shown) provided to be swingable with respect to the brake shaft 118, and a cam 120 that biases the brake shoe toward the friction plate 116. Prepare. The cam 120 is rotatably supported by the brake base 107, and a lever 121 and a return spring 122 for rotating the cam 120 are provided at the end. The lever 121 is operated by a brake handle (not shown).

  A rear wheel sprocket 86 is connected to the wheel hub 102 via a one-way clutch built in the transmission. A rim 123 is joined to the outer wall 102 b of the wheel hub 102, and a rear wheel spoke (not shown) is joined to the rim 123.

  The stator coil 113a of the motor 130 of the power unit 87 configured as described above is energized according to the pedaling force detected by the pedaling force detection unit 18. Then, the wheel hub 102 is rotated by the action of the magnetic field generated by this energization and the magnet 105, and the rear wheel sprocket 86 is rotated. The rotational force of the motor 130 is combined with the rotational force transmitted to the rear wheel sprocket 86 from the crankshaft 91 via the drive sprocket 84 and the chain 12 by human power to drive the wheel hub 102.

  The bicycle 100 according to the second embodiment is not limited to a bicycle with a drive assisting device, and can be a hybrid vehicle that independently drives the motor 130 regardless of the magnitude of the pedal effort.

  Next, a third embodiment of the present invention will be described. FIG. 9 is a left side view of the bicycle according to the third embodiment. The bicycle 200 includes a front assembly 201, a center assembly 202, a rear assembly 203, and a seat assembly 204. The front assembly 201 includes a head pipe 205 positioned in front of the vehicle body and a pipe-shaped front frame 206 that is joined to the head pipe 205 and extends substantially horizontally rearward. A front fork 207 is rotatably held on the head pipe 205 via a shaft portion formed on the upper portion thereof. A handle post 209 is coupled to the upper end of the shaft portion via a joint 208, and a steering handle 210 is coupled to the upper portion of the handle post 209. The joint 208 can be loosened by operating the knob 211 and the lever 212, and the handle post 209 can be folded around the joint 208 by these operations. A front wheel WF is rotatably supported at the lower end of the front fork 207.

  The front end of a front brake wire 213 extending downward from brake levers (not shown) provided at both ends of the steering handle 210 is coupled to a front brake 214 provided on the front fork 207. Further, one wire (rear brake wire) 215 is coupled to the brake lever, and the rear brake wire 215 extends rearward along the vehicle body and is coupled to the rear brake 216. The rear brake wire 215 is held so as not to hang by a stopper 217 provided on the front frame 206.

  The central assembly 202 has a casing 220 that forms a space for individually accommodating a power unit 218 and a battery 219 that supplies power to the power unit 218. That is, the casing 220 integrally constitutes a small chamber (drive unit housing) that houses the power unit and a small chamber (battery case) that houses the battery 219. The casing 220 is configured as a split frame made of a pair of left and right aluminum die-cast products.

  The power unit 218 includes a power transmission mechanism for each of the human power drive system and the motor drive system. The manual driving system includes a crankshaft 219 for inputting human power, a crank 220 coupled to both ends of the crankshaft 219, and a transmission gear mechanism for input human power. On the other hand, the motor drive system includes a motor 221 and a transmission gear mechanism for motor power. Of this gear mechanism, a pedal force detection unit 18 is attached to a resultant force shaft (described later). The gear mechanism and the like will be further described later.

  The casing 220 has a connecting portion 222 with the front frame 206 at the front, a connecting portion 223 with the seat assembly 204 at the upper front portion, and a connecting portion 224 that connects the rear assembly 203 at the rear.

  The rear assembly 203 includes a rear frame 225 coupled to the central assembly 202 by a connecting portion 224, a bearing portion 226 provided at a rear end of the rear frame 224, a driven side sprocket 227 supported by the bearing portion 226, and a rear wheel WR. Have The rear frames 225 are provided on the left and right sides of the vehicle body to form a pair, and a rear brake 216 is mounted on the upper part. The driven sprocket 227 is connected to a driving sprocket (described later) provided in the central assembly 202 by the chain 12.

  The seat assembly 204 includes a seat post 228 and a seat 229 provided at the upper end of the seat post 228, and a reflector 230 is attached to the seat post 228.

  A boss for holding the seat post 228 and a clamper for fastening the boss are provided in the connecting portion 223 provided at the upper front portion of the central assembly 202. The seat post 228 is attached to the casing 220 by fastening the boss with the clamper. Holds securely. By loosening the clamper, the seat post 228 can be moved up and down to adjust the height of the seat 229.

  The casing 220 is provided with a plurality of bosses for penetrating bolts that fasten and fix the divided left and right casings, and the bosses 231 are positioned on the extension line of the seat post 228 and the front upper portion and the outer periphery of the seat post 228. It is provided so as to contact each other. With such an arrangement, when a load is applied to the seat 229, it is possible to prevent the lower end of the seat post 228 from moving in the clockwise direction in the drawing around the connecting portion 223, and a large load applied to the seat 229 is also possible. It can be reliably supported.

  The connecting portion 222 between the front frame 206 and the casing 220 has a hinge jump lock device having a pivot extending in the vertical direction of the vehicle body. By releasing the lock of the lock device, the vehicle body is folded at the hinge pivot. It is also possible to separate the front assembly 201 and the central assembly 202 from each other by further uncoupling the hinges.

  A connecting portion 224 between the rear frame 225 and the casing 220 includes a boss formed on both the rear frame 225 and the casing 220, a bolt passing through the boss, and a nut screwed to the bolt (bolts and nuts are illustrated). Not composed of).

  FIG. 10 is a schematic diagram showing a gear arrangement constituting the power unit 218. In FIG. 10, a manpower drive gear 232 is coupled to the crankshaft 219 via a ratchet one way (described later). The manpower drive gear 232 meshes with a small gear 234 formed on the resultant force shaft 233, and the middle gear 235 of the resultant force shaft 233 meshes with a final gear 236 coupled to the output shaft 235. A drive side sprocket 238 connected to the driven side sprocket 227 and the chain 12 is coupled to the output shaft 237 (see FIG. 11).

  Further, a large gear 239 is coupled to the resultant force shaft 233 via a ratchet one-way (described later). The large gear 239 meshes with a small gear 241 coupled to the reduction shaft 240. The reduction shaft 240 is further provided with a large gear 242, which meshes with a pinion 244 coupled to the output shaft 243 of the motor 221.

  A pedal force detection unit 18 is attached to the end of the resultant force shaft 233. The treading force detection unit 18 includes a hydraulic sensor 36 and an oil reservoir 65. Details will be described later.

  In this configuration, the crankshaft 219 is rotated by the pedaling force input to the crankshaft 219 by the crank 220, and the rotation is transmitted to the resultant shaft 233 via the manpower drive gear 232 and the small gear 234.

  On the other hand, the rotation of the motor 221 is transmitted to the speed reduction shaft 240 via the pinion 244 and the large gear 242, and the rotation of the speed reduction shaft 240 is the resultant force via the small gear 241 and the large gear 239 on the resultant force shaft 233. It is transmitted to the shaft 233. In this way, the pedal force and the power of the motor 221 are combined on the resultant shaft 233, and the resultant driving force is transmitted to the output shaft 237 via the middle gear 235 and the final gear 238 to rotate the driving side sprocket 238. .

  11 is a cross-sectional view of the power unit at the AA position, and FIG. 12 is a cross-sectional view of the power unit at the BB position. 11 and 12, the power unit 218 includes a drive unit housing 247 including a right case 245 and a left case 246, and the crankshaft 219 is a bearing 248 held by the right case 245 and a bearing held by the left case 246. 249. A ratchet one-way 250 is attached to the left side (close to the bearing 249) in the drive unit housing 247 on the crankshaft 219, and the manpower drive gear 232 is engaged with the crankshaft 219 via the ratchet one-way 250.

  The resultant force shaft 233 is supported by a bearing 251 held by the right case 245 and a bearing 252 held by the left case 246. The resultant shaft 233 is provided with a small gear 234, a large gear 239, and an intermediate gear 235 in order from the left in the drawing. The large gear 239 is attached to the resultant force shaft 233 via the ratchet one way 253. The small gear 234 on the manpower drive gear 232 and the resultant force shaft 233 is a helical gear. At one end (right end in the figure) of the resultant force shaft 233, a piston accommodation chamber having a hydraulic chamber 254 and a piston 255 is formed.

  The reduction shaft 240 is supported by a bearing 256 held by the right case 245 and a bearing 257 held by the left case 256.

  12, the motor 221 includes an output shaft 243, a motor housing 257, bearings 258 and 259 provided on the motor housing 257, a stator (magnet) 261, a rotor 262 wound with a coil, a brush 263, and the like. Consists of.

  In FIG. 11, the output shaft 237 is supported by a bearing 264 held by the right case 245 and a bearing 265 held by the left case 256. The final gear 236 is coupled to the output shaft 237 by spline engagement.

  FIG. 13: is principal part sectional drawing of the power unit of the bicycle which concerns on 3rd Embodiment. 13, the same reference numerals as those in FIGS. 11 and 12 denote the same or equivalent parts.

  In FIG. 13, a ratchet one-way 250 is provided at a step portion 268 sandwiched between a flange 266 formed on the crankshaft 219 and the holding ring member 267, and the pawl of the ratchet one-way 250 The ratchet teeth 269 are locked. The holding ring member 267 is fixed by a stop ring 270 by restricting the position of the crankshaft 219 in the longitudinal direction. The positional relationship between the bearing 248 and the crankshaft 219 is defined by the stop ring 271.

  The large gear 239 on the resultant force shaft 233 is also provided with a ratchet one-way 253 at a step portion 274 sandwiched between a flange 272 formed on the resultant force shaft 233 and the holding ring member 273, similarly to the manpower drive gear 232. The claw of the one-way 253 is locked to the ratchet teeth 275 on the inner peripheral portion of the large gear 239.

  Since the manpower driving gear 232 and the small gear 234 of the resultant shaft 233 are helical gears, when the manpower driving gear 232 rotates, there is a thrust (parallel to the crankshaft 219) between the small gear 234 and the manpower driving gear 232. Force acting in any direction). In the present embodiment, the helical gear twist direction is set such that when the crankshaft 219 is rotated in the direction in which the bicycle 200 moves forward, a thrust (arrow 276) in the right direction in the figure is generated on the resultant force shaft 233.

  A piston 255 is housed in the piston housing chamber 277 of the right case 245 located on the right side of the resultant force shaft 233. The piston 255 is liquid-tightly accommodated in the piston accommodating chamber 277 by an O-ring 278 and is urged toward the resultant force shaft 233 by a spring 279. A ball (steel ball) 280 is interposed between the piston 255 and the end surface of the resultant force shaft 233. A hydraulic chamber 254 having a spring 279 is provided behind the piston 255 (opposite the resultant force shaft 233 side), and the hydraulic chamber 254 communicates with an oil reservoir in the oil reservoir 65. Note that the oil reservoir 65 and the hydraulic pressure sensor of the pedaling force detection unit are configured in the same manner as in the first embodiment (FIG. 5).

  With this configuration, the resultant force shaft 23 pushed by the piston 255 is urged to the left side in the drawing, so that when no pedal effort is applied to the crankshaft 219, there is no gap between the intermediate gear 235 and the bearing 251. A gap G is generated.

  When a pedaling force is applied to the crankshaft 219 in order to run the bicycle 200, the thrust shaft 233 tends to displace the resultant force shaft 233 in the direction in which the gap G is reduced (right side of the vehicle body). When the piston 255 is pushed into the piston accommodation chamber 277 until a check ball of an oil reservoir (not shown) is seated on the valve body, thereafter, the hydraulic pressure is generated by thrust through the incompressible oil in the piston 255 and the hydraulic chamber 254. The oil pressure acting on the pressure receiving portion 76 (see FIG. 5) of the sensor main body 4 of the sensor 36 is increased, and the sensor main body 4 outputs a detection signal corresponding to the thrust force (corresponding to the pedaling force).

  Note that when the driving force by the motor 221 is applied to the resultant force shaft 233 and the pedaling force is relatively small, the thrust force 276 is reduced. Therefore, the piston 255 is pushed by the spring 279 to displace the resultant force shaft 233. The gap G opens to the maximum value side. When the driving force is applied, the thrust force 276 is reduced, so that the piston 255 is displaced to the left side in the drawing, and the pressure in the hydraulic chamber 254 is reduced. As a result, this time, it is detected that the pedaling force has decreased, the auxiliary driving force by the motor 221 decreases, and the pedaling force increases, so the thrust force 276 increases again.

  Thus, the driving force by the motor is applied to the resultant shaft 233 by the detection signal output from the hydraulic sensor 36, and the pedaling force input to the crankshaft 219 by the crank 220 is reduced to a predetermined value or less.

  Subsequently, a fourth embodiment of the present invention will be described. FIG. 14 is a left side view showing the bicycle according to the fourth embodiment, and the same reference numerals as those in FIGS. 1 and 6 denote the same or equivalent parts. A bicycle 300 including the pedaling force detection device of the fourth embodiment is a bicycle in which a power unit is provided on the rear wheel side, as in the second embodiment. In FIG. 14, the ends of the main pipe 3, the standing pipe 4, and the chain stay 6 of the bicycle 300 are joined to a cylindrical holder 79 that is a component of a hub mechanism that supports the crankshaft 91. A drive sprocket 84 is connected to the crankshaft 91, and a rear wheel sprocket 86 is provided on the rear wheel side.

  An output shaft of a power unit 87 that applies auxiliary driving force to the rear wheel sprocket 86 is connected to the rear wheel sprocket 86. The power unit 87 may have the same configuration as that described with reference to FIG. Between the crankshaft 91 and the drive sprocket 84, a pedal force detection unit 170 including a hydraulic actuator 140, a hydraulic sensor 36, and a protection mechanism 180 of the hydraulic sensor 36 is mounted.

  Next, the configuration of the pedaling force detection unit 170 will be described. 15 is a view taken along the line CC of FIG. In FIG. 15, the crankshaft 91 is supported by ball bearings 171 and 172 provided at both ends of a cylindrical holder 79 extending in the vehicle body width direction. The ball bearing 171 on the drive sprocket 84 side includes a housing 173 screwed from one end of the cylindrical holder 79 and a plurality of balls 174, and the ball 174 is surrounded by the housing 173 and the step 91 a of the crankshaft 91. Accommodated in a designated space.

  On the other hand, the ball bearing 172 on the side far from the drive sprocket 84 includes a housing 175 screwed from the other end side of the cylindrical holder 79, a plurality of balls 176, and a nut 177 screwed to the outer periphery of the housing 175. Become. The ball 176 is accommodated in a space surrounded by the housing 175 and another step 91 b of the crankshaft 91. The nut 177 cooperates with the end of the cylindrical holder 79 and acts as a double nut for preventing the housings 173 and 175 from loosening.

  Of the crankshaft 91, the vehicle body right side crank 10R is attached to the end portion of the right portion 91R protruding from the ball bearing 171, and the vehicle body left side crank 10L is attached to the end portion of the left portion 91L protruding from the ball bearing 172. .

  A pedal force detection unit 170 is attached to the right portion 91 </ b> R of the crankshaft 91. The pedaling force detection unit 170 includes a hydraulic actuator 140 assembled to the crankshaft 91 together with the drive sprocket 84 and a hydraulic sensor 36 that detects hydraulic pressure generated in a hydraulic chamber (described later) by the hydraulic actuator 140.

  The hydraulic actuator 140 includes an attachment 141 that is fixed to the outer periphery of the right portion 91R of the crankshaft 91. The attachment 141 includes a cylindrical portion 141a that engages with the crankshaft 91 by, for example, a spline, and a disc portion 141b that extends from the end of the cylindrical portion 141a in the outer peripheral direction. The longitudinal position of the crankshaft 91 is restricted by the stop rings 142 and 143 which are located at both ends of the cylindrical portion 141a and engage with the outer periphery of the crankshaft 91. The hydraulic actuator 140 further includes a piston 144, a hydraulic chamber housing 145 that houses the piston 144, and a protection mechanism 180 for the hydraulic sensor 36.

  The hydraulic chamber housing 145 is formed with a boss 146 for preventing rotation of the hydraulic chamber housing 145. The detent boss 146 is covered with a cap 147, and the cap 147 is fitted to the treading force detection unit cover 148, and the treading force detection unit cover 148 is sandwiched between the housing 173 of the ball bearing 171 and the cylindrical holder 79. . The pedaling force detection unit cover 148 can be formed integrally with the chain cover 17.

  The configuration of the hydraulic actuator 140 will be described in detail with reference to FIG. FIG. 16 is an enlarged view of a main part of FIG. In FIG. 16, a hydraulic chamber housing 145 is mounted on the outer peripheral side of the cylindrical portion 141 a of the attachment 141. The hydraulic chamber housing 145 includes a cylindrical portion 145a whose inner peripheral surface is opposed to the outer peripheral surface of the cylindrical portion 141a of the attachment 141, and a disc portion 145b that extends from the end of the cylindrical portion 145a in the outer peripheral direction. Have. The peripheral edge of the disc portion 145 b forms an annular wall 150 that rises toward the right side of the vehicle body along the longitudinal direction of the crankshaft 91.

  A disc-shaped piston 144 is disposed between the inner peripheral surface of the annular wall 150 and the outer peripheral surface of the cylindrical portion 145a. The inner peripheral surface of the central portion (hub) 144 a of the piston 144 is engaged with the outer periphery of the cylindrical portion 145 a of the hydraulic chamber housing 145 via the annular seal 151. On the other hand, the outer peripheral edge of the piston 144 is engaged with the inner peripheral surface of the annular wall 150 of the hydraulic chamber housing 145 via the seal 152.

  Thus, a hydraulic chamber 153 is formed between the piston 144 and the hydraulic chamber housing 145. A wave washer 165 is disposed on the opposing surface of the piston 144 and the hydraulic chamber housing 145. The wave washer 165 exerts a force in a direction to increase the distance between the opposed surfaces of the piston 144 and the hydraulic chamber housing 145, and when the hydraulic pressure in the hydraulic chamber 153 decreases due to a decrease in the pedaling force, the ball washer 156, the attachment 141, and the drive sprocket 84 Make sure there are no gaps.

  The hydraulic chamber 153 is filled with incompressible oil. Near the outer periphery of the disk portion 145 b of the hydraulic chamber housing 145, a sensor mounting boss 154 is formed protruding in the direction opposite to the annular wall portion 148. The boss 154 is provided with a screw hole 154a for attaching a sensor that communicates with the hydraulic chamber 153, and the hydraulic sensor 36 is screwed into the screw hole 154a so that the sensing portion faces the hydraulic chamber 153. The hydraulic sensor 36 has a substantially cylindrical shape as a whole, and is arranged so that its longitudinal direction is directed to the longitudinal direction of the crankshaft 91, that is, the vehicle width direction of the bicycle 300, and is attached to the boss 154. The hydraulic sensor 36 is electrically connected to the controller 21 by a harness 155.

  In addition, a sensor protection mechanism 180 is provided at the other portion of the disk portion 145b of the hydraulic chamber housing 145 near the outer periphery. The sensor protection mechanism 180 will be described in detail later.

  A drive sprocket 84 is disposed between the attachment 141 and the piston 144. The drive sprocket 84 includes a hub 84 a and an outer ring portion 84 b, and both are coupled to each other by rivets 33. The disc portion 141b of the attachment 141 and the hub 84a of the drive sprocket 84 have a groove for receiving the ball 156, and the disc portion 141b and the hub 84a face each other with the ball 156 interposed therebetween. The hub 84a of the drive sprocket 84 has an annular wall portion 157 that rises along the longitudinal direction of the crankshaft 91. On the inner peripheral surface of the annular wall portion 157, the peripheral edge portion of the disc portion 141b of the attachment 141 is provided. It faces through an annular seal 158.

  A needle thrust bearing 159 is disposed between the hub 84 a of the drive sprocket 84 and the piston 144. On the other hand, a needle thrust bearing 162 that receives thrust applied to the disk portion 145b of the hydraulic chamber housing 145 is disposed around the cylindrical portion 141a of the attachment 141. A thrust plate 160 is provided on the end portion side of the cylindrical portion 141a with respect to the needle thrust bearing 162, and a stop ring 161 is disposed on the further end portion side of the cylindrical portion 141a from the thrust plate 160.

  The hydraulic actuator 14 having these components includes a needle thrust bearing 162 on the cylindrical portion 141a of the attachment 141 in a state where the drive sprocket 84, the piston 144, and the hydraulic chamber housing 145 are aligned with the attachment 141. After mounting and further mounting the thrust plate 160, the stop ring 161 is engaged with the cylindrical portion 141a, and the thrust plate 160 is fixed.

  A seal 163 is provided between the thrust plate 160 and the hydraulic chamber housing 145, and a seal 164 is provided between the hub 84 of the drive sprocket 84 and the piston 144.

  The operation of the pedal effort detection unit 170 will be described with reference to FIG. In FIG. 16, when the crankshaft 91 is rotated by the pedaling force, the attachment 141 is rotated together with this, and the rotation of the attachment 141 is transmitted to the drive sprocket 84 via the ball 156. The rotation of the drive sprocket 84 is transmitted to the rear wheel sprocket 86 by the chain 12 and is combined with the output of the power unit 87 to drive the rear wheel WR.

  The pedaling force for determining the driving force of the power unit 87 is detected by the differential between the attachment 141 and the drive sprocket 84. That is, when the pedaling force is small, the rotation of the attachment 141 is transmitted to the drive sprocket 84 via the ball 156, and the drive sprocket 84 rotates following the attachment 141. On the other hand, when the pedal force increases, that is, when the load on the rear wheel WR increases, this load acts as a force in a direction in which the drive sprocket 84 prevents the attachment 141 from rotating. Therefore, the relative positions of the drive sprocket 84 and the attachment 141 tend to change.

  However, since the ball 156 is interposed between the drive sprocket 84 and the attachment 141, the relative position can be changed by the drive sprocket 84 riding on the ball 156. That is, the drive sprocket 84, the attachment 141, and the ball 156 have a torque cam function. Here, since the position of the longitudinal direction of the crankshaft 91 is regulated with respect to the crankshaft 91 by the stop rings 142 and 143, the attachment 141 does not move with respect to the crankshaft 91. The piston is displaced toward the piston 144 in the longitudinal direction of the crankshaft 91. This displacement is transmitted to the piston 144 via the needle thrust bearing 159, and the piston 144 is guided by the outer peripheral surface of the cylindrical portion 145 a of the hydraulic chamber housing 145 and the inner peripheral surface of the annular wall portion 150, and the hydraulic chamber 153. It is displaced in the direction to reduce.

  Since the hydraulic chamber 153 is filled with incompressible oil, the pressure of the hydraulic chamber 153 increases due to the displacement of the piston 144, and the pressure increase is detected by the hydraulic sensor 36. The pressure in the hydraulic chamber 153 represents the amount of displacement in the rotational direction between the actuator 141 and the drive sprocket 84, that is, the pedaling force. Therefore, the detection signal of the hydraulic sensor 36 is transmitted to the controller 21, and the controller 21 sends an instruction to output a driving force corresponding to the pedaling force represented by this detection signal to the power unit 87.

  From the viewpoint of preventing the pressure in the hydraulic chamber 153 from rising excessively, it is desirable to provide the hydraulic sensor protection mechanism 180. FIG. 17 is an enlarged view of a main part of the pedaling force detection unit showing the hydraulic sensor protection mechanism. In FIG. 17, a hydraulic sensor protection mechanism 180 is provided at the peripheral edge of the hydraulic chamber housing 145. The hydraulic sensor protection mechanism 180 includes a body 181 and a cap 182 that is screwed to the body 181 and is in close contact with the seal ring 183.

  A valve device 185 is incorporated in a valve chamber 184 formed by the body 181 and the cap 182. The valve chamber 184 has a communication path 186 that reaches the hydraulic chamber 152. In the valve chamber 184, a cylindrical sheet 187 is arranged with the outer periphery sealed by a seal ring 188. A check ball 189 is disposed in the hole of the seat 187, and a relief valve 190 is disposed on the check ball 189 from the cap 182 side. A relief valve spring 191 that biases the relief valve 190 toward the check ball 189 is provided between the relief valve 190 and the cap 182. The cap 182 is formed with a recess 182a on the body 181 side. The recess 182a and the hollow portion of the seat 187 accommodate the relief valve 190 and the relief valve spring 191 and also function as an oil reservoir.

  According to this sensor protection mechanism 180, when the pressure in the hydraulic chamber 153 increases and the pressure in the communication path 186 exceeds the urging force of the relief valve spring 191, the check ball 189 moves away from the seat 187 and the oil in the hydraulic chamber 153 Flows into the oil reservoir. As a result, it is possible to protect the hydraulic sensor 36 by avoiding the pressure in the hydraulic chamber 153 from rising above a predetermined value.

  Thus, in the fourth embodiment, the pedal force is converted into the movement of the drive sprocket 84 in the longitudinal direction of the crankshaft 91 by the cam mechanism formed by the ball 156, the attachment 141, and the drive sprocket 84, and the piston 144 is moved. Can move. As a result, the pedaling force can be represented by the pressure in the hydraulic chamber 153.

  The bicycle 200 according to the third embodiment and the bicycle 300 according to the fourth embodiment are not limited to driving the motor 221 in accordance with the pedaling force, as with the bicycles 1 and 100, and when the pedaling force is not input. A configuration may be adopted in which the rear wheel is driven only by the motor 221 and a hybrid bicycle that drives the rear wheel by combining the human power and the motor driving force individually or by combining both.

  As described above, according to the first and second embodiments, it is possible to detect the pedal effort by detecting a slight displacement of the crankshaft by the hydraulic sensor. Moreover, in 3rd Embodiment, the pedal force can be detected by detecting the change of the axial direction of the resultant force shaft engaged with a crankshaft via a gear with a hydraulic sensor.

  Further, in the fourth embodiment, it is possible to easily detect the pedaling force with respect to the existing vehicle body frame structure only by performing processing that can be coupled with the attachment on one side (right side of the vehicle body) of the crankshaft 91, such as spline processing. Unit can be installed.

  Accordingly, in any of the embodiments, the rotation of the crankshaft is directly transmitted to the crank sprocket and the driving side sprocket without passing through the buffer member, and therefore, during pedaling, which is a concern in the conventional apparatus using the strain sensor. Lost motion disappears. Therefore, it is possible to prevent the user from feeling uncomfortable during pedaling due to the lost motion and to obtain a good riding comfort.

  Although the present invention has been described according to the embodiment in the present specification, the present invention is not limited to this. Those skilled in the art can implement the present invention by applying well-known techniques within the scope described in the claims. For example, in the third embodiment, the motor 221 is disposed below the speed reduction shaft 240, but the position of the motor 221 may be set behind the speed reduction shaft 240 (right side in FIGS. 9 and 10). For example, the motor 221 can be arranged so that the output shaft of the motor 221 is located at a position indicated by reference numeral 243a in FIG. As a result, the substantial height of the power unit 218 can be reduced.

  In the above-described embodiment, the present invention has been described with reference to a two-wheeled bicycle. However, a vehicle to which the treading force detection device of the present invention can be applied is not limited to a two-wheeled bicycle, but a three-wheeled vehicle or a four-wheeled vehicle. In short, any vehicle may be used as long as the vehicle is provided with a motor that is driven by a pedaling force input to the crankshaft and that is driven to assist the pedaling force according to at least the pedaling force.

  DESCRIPTION OF SYMBOLS 1,100,200 ... Bicycle with power auxiliary machine, 2 ... Head pipe, 3 ... Main frame, 6 ... Chain stay, 8, 87 ... Power unit, 9, 91, 219 ... Crankshaft, 10L, 10R ... Crank, 11, 130, 221 ... motor, 12 ... chain, 13, 84 ... crank sprocket, 14 ... resultant sprocket, 16, 86 ... rear wheel sprocket, 18 ... pedaling force detection unit, 26 ... power unit case, 27, 92 ... self-aligning ball bearing 28 ... Bearing, 35 ... Bearing housing recess, 36 ... Hydraulic sensor, 37 ... Sensor housing recess, 38 ... Piston, 39 ... Coil spring, 40 ... Sensor body, 41 ... O-ring, 65 ... Oil reservoir, 67 ... Oil reservoir, 68 ... Check valve, 76 ... Pressure receiving part, 79 ... Cylindrical holder, 89 Bearing box 93 ... second bearing box 140 ... hydraulic actuator 141 ... attachment 144 144 piston piston 145 hydraulic chamber housing 170 pedal force detection unit 180 hydraulic sensor protection mechanism 227 driven sprocket 238 ... Drive side sprocket

Claims (10)

The crankshaft (9) that rotates with the pedaling force input to the pedal crank (10L, 10R), the bearings (27, 28) that support the crankshaft (9) at two points, and the crankshaft (9) In a pedaling force detection device for a vehicle having a chain (12) bridged between a crank sprocket (13) and a rear wheel sprocket (16),
One of the bearings (27, 28) is disposed with a gap (G) with respect to the vehicle body frame,
The bearing (28) provided with the gap (G) by pedaling of the pedal crank (10L, 10R) is configured to be movable within the range of the gap (G).
The piston (38) disposed in contact with the outer periphery of the bearing (28) disposed with the gap (G) and displaced in accordance with the movement of the bearing (28), and the pressure by the piston (38) A vehicle, comprising: a fluid pressure chamber (42) that accommodates an incompressible fluid to be compressed; and a fluid pressure sensor (36) that outputs a pedal depression force corresponding to the pressure in the fluid pressure chamber (42). Pedal force detection device.   Among the bearings (27, 28), the bearing arranged with the gap (G) is a bearing (28) on the crank sprocket (13) side, and the outer peripheral surface of the bearing (28) and the bearing The dimension of the bearing receiving recess (35) is determined so that the gap (G) is formed at least on the vehicle body rear side with respect to the bearing receiving recess (35) for storing (28). 2. A pedaling force detection device for a vehicle according to claim 1,   3. The pedaling force detection device for a vehicle according to claim 2, wherein a bearing (27) far from the crank sprocket (13) among the plurality of bearings (27, 28) is a self-aligning bearing. 4. Bearings (94a, 94b, 92) that support the crankshaft (91) that is rotated by the pedal force input to the pedal crank (10L, 10R) at two points, and a crank sprocket (84) that is coupled to the crankshaft (91) And a pedaling force detection device for a vehicle having a chain (12) spanned between a crank sprocket (84) and a rear wheel sprocket (86),
A bearing box (89) that houses a bearing (92) that supports a side of the bearing (94a, 94b, 92) far from the crank sprocket (84) side;
A second bearing box (93) that houses a bearing (94a, 94b) that supports a side close to the crank sprocket (84) side of the bearings (94a, 94b, 92);
A cylindrical holder (79) for holding the outer periphery of the bearing box (89) and the second bearing box (93);
A fluid pressure piston (38) and a fluid pressure sensor (36) having a fluid pressure chamber (42) containing an incompressible fluid that transmits the displacement of the fluid pressure piston (38) to the pressure receiving part (76),
The second bearing housing (93) is engaged with each other with a gap (G) so as to be displaceable with respect to the cylindrical holder (79) and from the cylindrical holder (79). Having a portion (93a) projecting to the crank sprocket (84) side,
A pedaling force detecting device for a vehicle, wherein a piston (38) of the fluid pressure sensor (36) is disposed in contact with the protruding portion (93a) of the second bearing housing (93).   The rear wheel sprocket (86) is driven by a pedal force input to the crankshaft (91) and an output of a power unit (87) provided on a hub of the rear wheel (WR). 5. A pedaling force detection device for a vehicle according to 4.   A piston (38), a pressure receiving part (76), a fluid pressure chamber (42), and a sensor body (40) connected to the fluid pressure chamber (42) of the fluid pressure sensor (36) are arranged in a line, and The vehicle treading force detection device according to claim 1 or 4, wherein the alignment direction is set along a longitudinal direction of the vehicle body. A crankshaft (219) that is rotated by a pedaling force input to the pedal crank (10L, 10R), a resultant shaft (233) that is coupled to the crankshaft (219) via a gear pair (232, 234), and driving assistance A motor (221) as a machine, a reduction gear that decelerates the rotation of the output shaft (243) of the motor (221) and connects to the resultant force shaft (233), and the rotation of the resultant force shaft (233) externally The power unit output shaft (237) led out to the power unit, the drive side sprocket (238) coupled to the power unit output shaft (237), and a chain (between the drive side sprocket (238) and the driven side sprocket (227) ( 12) a pedal effort detecting device for a vehicle having
The gear pair (232, 234) is constituted by a helical gear;
The resultant force shaft (233) is moved by bearings (251, 252) so that the resultant force shaft (233) can be displaced by a predetermined amount by thrust generated in the gear pair (232, 234) by the rotation of the crank shaft (219). While supporting
The piston (255) disposed in contact with the end of the resultant force shaft (233) and displaced in accordance with the displacement of the resultant force shaft (233) due to the thrust, and the non-compressed portion that transmits the displacement of the piston (255) to the pressure receiving portion And a fluid pressure sensor (36) having a fluid pressure chamber (254) containing a sexual fluid.   A relief device (68) is provided for discharging the fluid in the fluid pressure chamber (42) from the fluid pressure chamber (42) when the hydraulic pressure in the fluid pressure chamber (42) becomes an excessive pressure of a predetermined value or more. The vehicle treading force detecting device according to any one of claims 1 to 7, wherein A crank sprocket (84) for transmitting the pedal crankshaft (91) and the manual torque applied to the pedal crankshaft (91) to the rear wheel (WR) by the drive chain (12), and the pedal crankshaft (91) A treading force detecting device having a torque detecting means (36) for detecting the generated human power torque,
A piston (144) provided to be displaceable in the longitudinal direction of the pedal crankshaft (91);
The piston (144) is provided on the side of the crank sprocket (84), and the piston (144) is driven by a difference between a rear wheel load driven by the crank sprocket (84) and a manual torque applied to the pedal crankshaft (91). A mechanism (141, 156) for displacing in the longitudinal direction of the pedal crankshaft (91);
A hydraulic chamber (153) in which the internal hydraulic pressure changes according to the displacement of the piston (144),
The torque detection means (36) is connected to the hydraulic chamber (153), and is configured to detect the hydraulic pressure of the hydraulic chamber (153) as information representative of the human torque. Vehicle treading force detection device.   The vehicle treading force detecting device according to claim 9, wherein the torque detecting means (36) is arranged such that a longitudinal direction thereof is directed in a vehicle width direction.

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