JP2008045612A - Elastic support ring and steering device - Google Patents

Abstract

A structure for smoothly moving a steering wheel forward while absorbing a shock load applied to a steering wheel from a driver's body when a secondary collision occurs.
A rear end portion of a push-pull rod 22 and a coupling bracket 24 for adjusting the front / rear position of the steering wheel are coupled via an elastic support ring 25a. The elastic support ring 25a is provided with a plurality of elastic convex portions 27a, 27a that are long in a direction orthogonal to the displacement direction. For this reason, it is possible to efficiently supply the lubricant to the tip surfaces of the elastic convex portions 27a and 27a. Accordingly, each of the elastic convex portions 27a and 27a can exert a desired resistance, and the axial displacement between the push-pull rod 22 and the coupling bracket 24 can be smoothly performed. The above problems can be solved.
[Selection] Figure 3

Description

  The elastic support ring according to the present invention is disposed between a pair of members that can be combined in a telescope shape, for example, and these two members are coupled so as to be at least contractible. The steering device of the present invention is used to allow the steering wheel to be displaced forward while absorbing the impact applied to the steering wheel from the driver's body in the event of a collision, for example.

  As shown in FIG. 15, the steering device for giving the steering angle to the steered wheels transmits the movement of the steering wheel 1 to the steering gear via the steering shaft 2 and gives the steered angle to the left and right steered wheels 3. Like. Since the positional relationship between the steering wheel 1 and the driver's seat changes depending on the physique and driving posture of the driver, in order to realize a good driving posture, the steering wheel 1 is added to the front / rear position adjusting device for the driver's seat. There may be a case where a device for adjusting the front-rear position is required. As such an adjusting device, a longitudinal position adjusting device called a telescopic steering device is widely used. In addition, an electric position adjustment device for a steering wheel that performs position adjustment by an electric motor based on a switch operation has been widely used, for example, as described in Patent Documents 1 and 2.

  For example, FIG. 16 shows an electrically operated front / rear position adjustment device for a steering wheel described in Patent Document 2. In the case of this conventional structure, as the steering column 4, an outer column 5 and an inner column 6 that are telescopically combined are used. The outer column 5 is disposed on the front side (left side in FIG. 16) of the inner column 6. The steering shaft 2 is rotatably supported with respect to the inner column 6 in a state where the inner column 6 is inserted, and protrudes rearward from the rear end edge of the inner column 6 at the rear end portion of the steering shaft 2. The steering wheel 1 is supported and fixed to the part. When the front / rear position of the steering wheel 1 is adjusted, the inner column 6 is moved in the front / rear direction with respect to the outer column 5.

  In order to make this movement in the front-rear direction electric, in the structure shown in FIG. 16, the rear end portion of the adjusting screw rod 8 (FIG. 16) is attached to the support plate 7 fixed to the rear end portion of the inner column 6. The right end) is supported and fixed. Further, the electric screw 9 is provided for rotation only in the male screw portion 9 provided at the front end portion (the left half portion in FIG. 16) of the adjusting screw rod 8 and in the housing 10 fixed to the outer peripheral surface of the outer column 5. Thus, a feed screw mechanism is configured by screwing an adjustment nut that rotates in a desired direction. When the front / rear position of the steering wheel 1 is adjusted, the inner column 6 is pushed / pulled in the axial direction (left / right direction in FIG. 16) by the feed screw mechanism to extend / contract the steering column 4. Since the steering shaft 2 is supported only inside the inner column 6 so as to be rotatable only, and is extendable and contractible by a spline engaging portion, the steering wheel 4 is expanded and contracted as the steering column 4 is expanded and contracted. The front and rear position of 1 can be adjusted.

  At the time of a car collision, a so-called secondary collision in which the driver's body (mainly the chest or head) collides with the steering wheel 1 is generated following a so-called primary collision in which the automobile collides with an object such as another automobile. To do. For this reason, it is necessary to suppress the impact received by the driver during the secondary collision and to protect the life of the driver. Therefore, in order to reduce the impact applied to the driver's body during the secondary collision, the steering wheel 1 is accompanied by the secondary collision regardless of the presence of the steering wheel position adjusting device as described above. It is necessary to have a structure in which is displaced forward.

  In the case of the structure shown in FIG. 16, since the steering column 4 and the steering shaft 2 are both extendable and retractable structures, the structure in which the steering wheel 1 is displaced forward along with the secondary collision can be used. Easy to configure. On the other hand, the adjustment screw rod 8 does not shrink the entire length as it is, and is stretched between the outer column 5 and the inner column 6 constituting the steering column 4, so that the steering column 4 is not shrunk. Disappear. Of course, the outer column 5 is supported with respect to the vehicle body so as to drop forward due to the secondary collision by the structure as described in, for example, Patent Documents 3 and 4. Even if the screw rod 8 is present, the forward displacement of the steering wheel 1 is not completely stopped.

  However, the amount of forward displacement of the steering wheel 1 is reduced in the initial stage of the secondary collision, and the amount of forward displacement of the steering wheel 1 is reduced by the amount that the steering column 4 is not contracted. It is disadvantageous from the aspect of enhancing protection. Further, in the case of a structure in which the steering column 4 is dropped from a fixed part such as a dashboard without reducing the overall length and the steering wheel 4 is allowed to move forward, the components such as the steering wheel and the steering column are removed after dropping. The posture becomes unstable. As a result, the relationship between the steering wheel and the driver's body is shifted. This relationship is disadvantageous from the standpoint of ensuring the function of the airbag device or from the standpoint of preventing collision between the driver's feet, hips, and the like and the components of the steering device. Furthermore, when a secondary collision occurs, in the case of a structure in which the entire components of the steering device including the steering column 4 are dropped from the fixed portion and start to be displaced forward, the operation is performed at the moment when the secondary collision occurs. The impact load (peak load) applied to the person's body increases, which is disadvantageous from the viewpoint of driver protection.

  For this reason, Patent Document 2 describes an invention relating to an adjusting screw rod 8a that has a structure as shown in FIG. The adjustment screw rod 8a is formed by connecting a cylindrical outer cylinder 11 and an inner shaft 12 with pins 13 made of synthetic resin or soft metal. Such an adjusting screw rod 8a shortens the entire length as the pin 13 is broken by an impact load applied at the time of a secondary collision. For this reason, the adjusting screw rod 8a is not stretched between the outer column 5 and the inner column 6, and the steering column 4 is allowed to contract during a secondary collision.

  However, it is difficult to ensure the coaxiality of the adjusting screw rod 8a composed of the outer cylinder 11 and the inner shaft 12 over the entire length. In other words, the portion near the one end and the portion near the other end of the adjusting screw rod 8a are easily eccentric from each other. In the case of eccentricity, a non-uniform force acts on the threaded portion between the male screw portion 9 and the nut of the adjusting screw rod 8a, and the adjusting screw rod 8a is adjusted to adjust the front-rear position of the steering wheel 1. When rotating the, it becomes easy to generate unpleasant humor and unpleasant vibration. Furthermore, at the time of a secondary collision, there is a possibility that the outer cylinder 11 and the inner shaft 12 cannot be smoothly displaced relative to each other in the axial direction.

  Also, the nut that constitutes the feed screw mechanism together with the adjustment screw と し is made of synthetic resin, and the female screw part of this nut is broken at the time of a secondary collision, thereby enabling the axial displacement of the adjustment screw 変 位 with respect to this nut. It is also possible to make the column retractable. However, when such a structure is adopted, the reliability (hardness to breakage) of the threaded portion of the adjusting screw 雄 and the nut in the normal state is ensured, and the secondary collision At times, it is difficult to design the internal thread portion to ensure breakage.

  Furthermore, in any structure, the steering wheel can be allowed to move forward in the event of a secondary collision, but the steering wheel is moved forward while absorbing impact energy applied to the steering wheel from the driver's body. It cannot be provided with a so-called shock absorbing function. In order to provide this shock absorbing function, an energy absorbing member is provided between the dashboard and the steering column, which is plastically deformed by absorbing the shock energy and allows the steering column to move forward. Things can also be considered. However, in this case, a separate energy absorbing member is required, and parts production, parts management, and assembly work are all troublesome, which increases the production cost of the steering device with an electric position adjustment mechanism.

  Incidentally, Patent Document 5 and the like describe a limit ring that functions as a torque limiter. FIG. 18 shows the limit ring 14 described in Patent Document 5. The limit ring 14 is formed by intermittently forming convex portions 16, 16 that are long in the axial direction of the main body 15 on the outer peripheral surface of the cylindrical main body 15 in the circumferential direction. Each of the convex portions 16 and 16 can be elastically deformed in the radial direction of the limit ring 14. The limit ring 14 having such a configuration is incorporated between a pair of members that transmit rotational torque, and the magnitude of the frictional resistance exerted by each of the convex portions 16 and 16 and the transmitted torque is small or large. Depending on the relationship, the transmission state of torque is switched.

  The limit ring 14 configured and operated as described above is a portion that allows relative displacement in the axial direction during a secondary collision (for example, the inner portion of the outer cylinder 11 shown in FIG. 17). It can be considered to be used as a coupling member having an impact absorbing function between the peripheral surface and the outer peripheral surface of the inner shaft 12. That is, it is conceivable that the plurality of convex portions 16 and 16 exhibit sliding resistance (frictional force) with the mating surface, thereby absorbing an impact load. However, there is a possibility that a desired shock absorbing function cannot be obtained by simply incorporating the limit ring 14 having the above-described configuration as it is.

  That is, the convex portions 16 and 16 provided on the limit ring 14 have their length directions orthogonal to the rotational direction (axial direction) for the purpose of exerting resistance in the rotational direction. ). For this reason, when the limit ring 14 having such a configuration is incorporated as it is in a portion that performs relative displacement in the axial direction, the length directions of the convex portions 16 and 16 coincide with the displacement direction. . For this reason, among these convex parts 16 and 16, the edge part located ahead with respect to the displacement direction may scrape out lubricant such as grease applied to the mating surface. Therefore, depending on the state of use, it may be difficult for the initial operation of relative displacement to be performed smoothly, or it may be difficult to continuously exert stable resistance on each of the convex portions 16 and 16. Further, even when the lubricant is held in the valleys between the convex portions 16 and 16 adjacent to each other in the circumferential direction, it is difficult to supply the lubricant to the sliding contact surface (friction surface). There is a possibility that it will be disadvantageous in terms of smoothing.

  Therefore, in order to solve the above-described problems, the length directions of the limit rings 14 are made to coincide with the directions orthogonal to the displacement direction (long in the circumferential direction of the limit ring 14). It is conceivable to form a plurality of convex portions (or concave portions), but in this case, it is difficult to secure the length dimension of each convex portion (the processing of convex portions that are long in the bending direction in the arc portion). difficult). In addition, when a plurality of convex portions that are long in the circumferential direction of the limit ring 14 are formed in this way, convex portions having other shapes (for example, convex portions that are long in the axial direction of the limit ring 14) are aligned. Even if it tries to form, it becomes difficult to secure a formation space. In this way, when the cylindrical limit ring 14 is used as it is, the degree of freedom is reduced with respect to forming a plurality of convex portions (or concave portions) of various shapes and sizes, and desired resistance is exhibited. Things can be difficult. By the way, the limit ring 14 is originally used by being incorporated in a portion between a pair of rotating members, and it is necessary to make it cylindrical, but it is a portion that performs only relative displacement in the axial direction. For example, it is not always necessary to have a cylindrical shape.

JP-A-9-11915 JP 2003-276616 A Japanese Patent Laid-Open No. 11-165543 JP 2000-233758 A JP 2005-1114025 A

  In view of the above-described circumstances, the present invention has been invented to realize a structure capable of imparting a desired resistance to the relative displacement in the axial direction of a set of members. In addition, the present invention realizes a structure capable of obtaining a desired shock absorbing function as required.

Of the elastic support ring and the steering device of the present invention, the elastic support ring described in claim 1 is formed by bending (press molding or the like) a belt-like metal plate having elasticity, for example, A plurality of elastic protrusions formed in a state protruding from the surface of the main body. Then, the shaft member is used by being sandwiched between the outer peripheral surface of the shaft member and the inner peripheral surface of the insertion hole through which the shaft member can be inserted in a state in which the dimension in the radial direction is elastically compressed. A mating member having an insertion hole is coupled so as to allow relative displacement over the axial direction of the shaft member.
In particular, in the case of the elastic support ring according to claim 1, the main body portion includes a pair of flat plate portions arranged substantially parallel to each other in a state of being separated from each other, and a portion continuous from both edges in the width direction of both flat plate portions. The elastic convex portions are formed on at least one flat plate portion so as to be elastically deformable in the front and back directions of the flat plate portion.
In addition, although the shape is not ask | required about each said connection part, it can also be made into a semi-cylindrical shape, can also be made into a flat surface, and also can be made into a polygonal cross-section.

Further, when the invention described in claim 1 as described above is implemented, preferably, as described in claim 2, for example, in any part of the two flat plate portions and the two connecting portions, A slit portion corresponding to a gap between both edges in the length direction of the metal plate is provided.
In carrying out the above-described inventions according to claims 1 and 2, for example, as described in claim 3, a plurality of elastic convex portions formed on the flat plate portion are respectively connected to the shaft member. It has a long shape in the width direction of the flat plate portion, which coincides with the axial direction.
Alternatively, the plurality of elastic convex portions formed on the flat plate portion have a long shape in a direction orthogonal to the width direction of the flat plate portion, as described in claim 4.
Alternatively, each of the plurality of elastic convex portions formed on the flat plate portion has a substantially circular shape as described in claim 5.
When carrying out the inventions described in the third to fifth aspects, the elastic convex portions can be alternately or irregularly formed toward the inner side and the outer side of the elastic support ring.
Moreover, when implementing the invention described in claims 1 to 5 as described above, preferably, the elastic convex portion is formed not only in the flat plate portion but also in the connecting portion as described in claim 6. The shape (including direction) of the elastic convex portion formed in the connecting portion is not limited, but the planar shape can be, for example, a substantially rectangular shape, a substantially oval shape, a substantially oval shape, a substantially circular shape, or the like.
Moreover, when implementing the invention described in claims 1 to 6 described above, preferably, as described in claim 7, the elastic support ring has a predetermined value between the shaft member and the mating member. Only when an impact load having a magnitude exceeding 1 is applied, it is used as an impact absorbing member that absorbs the energy of the impact and allows a relative displacement in the axial direction between the shaft member and the mating member.

The steering apparatus according to the eighth aspect of the present invention includes a steering column, a driven member, a push-pull rod, a coupling member, a driving member, and an electric motor.
Among these, the steering column supports a steering shaft rotatably inside.
The driven member is coupled to a part of the steering column.
The push-pull rod is disposed in the axial direction of the steering column.
Moreover, the said coupling member couple | bonds the one end part of the said push-pull rod, and the said to-be-driven member so that isolation | separation is possible.
The drive member is rotatably supported around a portion near the other end of the push-pull rod, and displaces the push-pull rod in the axial direction of the steering column as it rotates.
The electric motor is for rotating the drive member.
Then, based on the relative displacement between the drive member and the push-pull rod based on the energization of the electric motor, the steering column is displaced, and the position of the steering wheel supported by the end of the steering shaft is adjustable. In addition, the coupling portion between the push-pull rod and the driven member is configured to be separable based on an impact load applied to the steering wheel at the time of collision.
Particularly, in the steering device according to an eighth aspect, the coupling member is the elastic support ring according to the seventh aspect.

  On the other hand, in the steering device according to the ninth aspect, the inner column and the outer column constituting the steering column are coupled by the elastic support ring according to any one of the first to seventh aspects.

  In the case of the elastic support ring of the present invention configured as described above, a pair of flat plate portions are provided and a plurality of elastic convex portions are formed on at least the flat plate portion. A desired resistance can be imparted when the pair of members (the shaft member and the mating member) are displaced relative to each other in the axial direction. That is, in the case of the present invention, by providing a pair of flat plate portions on the elastic support ring, the degree of freedom (the degree of design freedom regarding the shape and direction) of the elastic convex portions that can be formed is improved. For this reason, a desired resistance can be imparted to the relative displacement in the axial direction by these elastic convex portions.

In addition, according to the invention described in claim 2, the internal dimensions of the elastic support ring can be easily expanded and reduced, the assembly work of the elastic support ring can be facilitated, and the manufacturing is made possible by the presence of the slit portion. Since the error can be absorbed, there is no need to strictly regulate the shape accuracy and dimensional accuracy required for the component parts and the assembly accuracy of each component part, which is advantageous in terms of cost reduction.
According to the invention described in claims 3 to 5, the use and purpose of use of the elastic support ring (for example, whether it is used for a part that is instantaneously separated or is used for a part that continuously gives resistance) Etc.), the desired resistance can be easily exhibited.
In particular, according to the third aspect of the present invention, the lubricant such as grease is held between the adjacent elastic convex portions arranged in the displacement direction (axial direction of the elastic support ring) (valley portion). The lubricant can be efficiently supplied to the friction surface. For this reason, it is possible to easily perform the initial operation of relative displacement, and it is possible to continuously provide a stable resistance. For this reason, when the elastic support ring of the present invention is used as an impact absorbing member as described in claim 7, a desired impact absorbing function can be obtained.
Moreover, according to the invention described in claim 6, it is easy to ensure the coaxiality of the two members that are relatively displaced, and smooth relative displacement can be performed. Further, each surface constituting the elastic support ring can be effectively used, and the elastic support ring can be easily downsized (the axial length is shortened). It is also possible to finely adjust the magnitude of the resistance.
According to the seventh aspect of the present invention, the resistance (frictional force) exhibited by each of the elastic convex portions can be used to absorb impact energy. That is, according to the seventh aspect of the present invention, it is possible to finely set the magnitude of the impact load that initiates the relative displacement, and it is also possible to finely adjust the amount of shock energy absorbed.

Further, according to the steering device described in claim 8, it is possible to realize a steering device that has both an electric front / rear position adjustment function of the steering wheel and an impact absorbing function. In particular, in the case of the invention described in claim 8, a desired resistance is provided against the detachment operation between the proximal end portion (rear end portion) of the push-pull rod and the driven member at the time of the secondary collision. Since it can be applied, a desired shock absorbing function can be obtained. For this reason, it is possible to enhance the protection of the driver in the event of a collision.
Further, in the case of the invention described in claim 9, the outer column and the inner column constituting the steering column can be connected to each other in a stretchable manner with a simple structure. Further, the present invention provides, for example, a steering apparatus having an impact absorbing function for contracting the steering column while absorbing an impact load applied at the time of a secondary collision, as in the case of the invention described in claim 7. Available.
The present invention can also be used as an auxiliary member for smoothly performing the expansion and contraction operation of the outer column and the inner column. In this case, it is not necessary to increase the processing accuracy of the inner peripheral surface of the outer column and the outer peripheral surface of the inner column, and the processing cost can be reduced.

[First example of embodiment]
FIGS. 1-7 has shown the 1st example of embodiment of this invention corresponding to Claims 1-8. This example shows a structure in which a telescopic steering device for adjusting the front-rear position of the steering wheel 1 is provided with an impact absorbing function. The steering wheel 1 is supported and fixed at a rear end portion of the steering shaft 2a at a portion protruding rearward from the rear end portion (right end portion in FIGS. 1 and 2) of the steering column 4a. The steering column 4a has a back portion of the outer column 5a disposed on the front side (left side in FIGS. 1 and 2) and a front portion of the inner column 6a disposed on the rear side (right side in FIGS. 1 and 2). It is a telescopic steering column that can be extended and retracted by being fitted in such a manner that it can be slid in the axial direction. Such a steering column 4a expands and contracts its entire length by changing the fitting length between the outer column 5a and the inner column 6a. Of these outer column 5a and inner column 6a, the outer column 5a is supported to the vehicle body by brackets (not shown) (generally, a pair of upper and lower lower brackets and upper brackets). Accordingly, the inner column 6a is displaced in the front-rear direction based on the expansion and contraction of the steering column 4a.

  The steering shaft 2a is spline-engaged with a front end portion of a circular tubular outer shaft 17 provided on the rear side and a rear end portion of the inner shaft 18 provided on the front side. Accordingly, both the shafts 17 and 18 can freely transmit and receive a rotational force and at the same time extend and contract. The portion near the rear end of the middle portion of the outer shaft 17 constituting such a steering shaft 2a can be rotated only inside the rear end of the inner column 6a by a rolling bearing 19 such as a single row deep groove type ball bearing. It is supported (with axial displacement prevented). Accordingly, the outer shaft 17 is displaced in the front-rear direction along with the displacement of the inner column 6a in the front-rear direction together with the steering wheel 1 supported and fixed at the rear end thereof.

  In order to displace the inner column 6a in the front-rear direction, an electric feed screw mechanism 20 is provided between the inner column 6a and the outer column 5a. Of the feed nut 21 and the push / pull rod 22 constituting the feed screw mechanism 20, the feed nut 21 as a drive member is placed in the housing 23 fixed to the outer peripheral surface of the outer column 5a. In a state where it is screwed with a male thread formed at the front end (left half of FIGS. 1 and 2), only rotation is supported. Then, by rotating the feed nut 21 in a predetermined direction by an electric motor (not shown), the push / pull rod 22 is displaced in the axial direction (left and right direction in FIGS. 1 and 2) and coupled to the inner column 6a. The inner column 6a is displaced in the axial direction through a crank-type coupling bracket 24, which is a driven member, so that the front-rear position of the steering wheel 1 is adjusted. In the case of this example, the coupling portion between the coupling bracket 24 fixed to the inner column 6a and the push-pull rod 22 is configured to be separable based on an impact load applied at the time of collision.

  That is, an elastic support ring 25a as shown in FIG. 4A is incorporated in the connecting portion between the connecting bracket 24 and the push-pull rod 22. The elastic support ring 25a is formed by bending an elastic band-shaped metal plate such as press working. As the metal plate having elasticity, SUP6 (silicon manganese steel), SUP9 or SUP9A (manganese chromium steel), SUP11A (manganese chromium boron steel), SUP10 (chromium vanadium steel), which are general spring steels, Stainless steel (SUS304, SUS302, SUS631), brass or the like can be used.

  The elastic support ring 25a is composed of a cylindrical main body portion 26 and a plurality of elastic convex portions 27a and 27b. Of these, the main body portion 26 is disposed substantially in parallel with being separated from each other. A pair of flat plate portions 28 and 28 are provided. In addition, a semi-cylindrical curved plate that connects the two flat plate portions 28 and 28 to the width direction of both the flat plate portions 28 and 28 {the left-right direction in FIG. Portions 29 and 29 are provided. Further, as shown in FIG. 5, the curvature radius r of each of the curved portions 29, 29 is set to one half (r = 1 / 2L) of the distance L between the flat plate portions 28, 28. In addition, a slit portion 30 corresponding to a gap between both edges in the length direction of the metal plate is provided in the intermediate portion in the width direction of the curved plate portion 29 on the one side (right side in FIG. 4A). The elastic support ring 25 a is freely expandable and contractable in the radial direction due to the presence of the slit portion 30. For this reason, the assembly work of the elastic support ring 25a can be facilitated, and manufacturing errors can be absorbed. Therefore, it is not necessary to strictly regulate the shape accuracy and dimensional accuracy required for the inner peripheral surface of the insertion hole 32 described later and the shape of the outer peripheral surface of the rear end portion of the push-pull rod 22, and from the viewpoint of cost reduction. Become advantageous. The slit portion 30 may be one in which both ends in the axial direction of the elastic support ring 25a are linearly continuous in the axial direction, and as shown in FIG. 6, the axial direction of the elastic support ring 25a. You may incline and provide. The slit portion 30 may be provided in the flat plate portion 28 instead of the curved plate portion 29.

  The flat plate portions 28, 28 constituting the elastic support ring 25a are elastically deformed in the front and back directions of the flat plate portions 28, 28 in a state of protruding from the inner side surfaces of the flat plate portions 28, 28. A plurality of flexible protrusions 27a and 27a (five for each flat plate portion 28 in the illustrated example) are formed. Each of the elastic convex portions 27a and 27a has a shape that is long in the circumferential direction of the elastic support ring 25a (the width direction of the flat plate portions 28 and 28 and the left and right direction in FIG. 4A). The elastic support ring 25a is arranged in the axial direction {vertical direction in FIG. 4A}. Further, flat surface portions 31, 31 that exist on a virtual plane substantially parallel to the flat plate portions 28, 28 are provided on the tip surfaces of the elastic convex portions 27 a, 27 a. On the other hand, the curved plate portions 29, 29 have a plurality of elastic pieces 27b that can be elastically deformed in the radial direction while projecting from the inner peripheral surfaces of the curved plate portions 29, 29. 27b is formed. Each of the elastic pieces 27b and 27b has a shape that is long in the axial direction of the elastic support ring 25a {vertical direction in FIG. 4A}, and is arranged in the circumferential direction of the elastic support ring 25a. .

  In the case of this example, in order to incorporate the elastic support ring 25a having the above-described configuration, the coupling bracket 24 is formed with an insertion hole 32 having an oval cross-sectional shape on the inner peripheral surface. . The inner diameter (major axis and minor axis) of the insertion hole 32 is slightly smaller than the outer diameter (major axis and minor axis) in the free state of the elastic support ring 25a. Also, the cross-sectional shape of the push-pull rod 22 is an oval shape on the outer peripheral surface of the rear end portion or intermediate portion thereof.

  Incidentally, the coupling strength by the elastic support ring 25a (the magnitude of the spring constant of each elastic piece 27a, 27b, etc.) is set as follows. That is, between the outer peripheral surface of the main body portion 26 constituting the elastic support ring 25a and the distal end surfaces of the elastic pieces 27a and 27b, the inner peripheral surface of the insertion hole 32, and the outer peripheral surface of the push-pull rod 22. A resistance sufficiently larger than the resistance acting when the steering column 4a and the steering shaft 2a are contracted, which acts when adjusting the front-rear position of the steering wheel 1, is applied. However, this resistance is suppressed to a magnitude that does not support the impact load applied to the coupling portion between the coupling bracket 24 and the push-pull rod 22 in a secondary collision.

  When an impact load directed forward (to the left in FIGS. 1 and 2) is applied from the steering wheel 1 to the inner column 6a through the outer shaft 17 due to a secondary collision resulting from a collision accident, The column 6a is displaced forward. At this time, the outer column 5a remains in the same position. That is, as the secondary collision progresses, the outer column 5a may also be detached from the support portion of the vehicle body and start to move forward. However, at least in the initial stage of the secondary collision, the outer column 5a remains in the same position, and only the inner column 6a is displaced forward.

  Thus, when only the inner column 6 a is displaced forward, the rear end portion of the push-pull rod 22 comes out of the insertion hole 32, and the coupling bracket 24 is displaced forward with respect to the push-pull rod 22. In particular, in this example, this displacement can be performed smoothly. That is, in the case of this example, as described above, the elastic support ring 25a is incorporated in the insertion hole 32 with the outer diameter reduced, and the both of the elastic support rings 25a. The flat plate portions 28 and 28 are provided with elastic pieces 27a and 27a that are long in a direction perpendicular to the displacement direction. For this reason, a lubricant such as grease can be held between the adjacent elastic pieces 27a and 27a, and this lubricant can be efficiently used at the tip surfaces (flat surface portions) of the elastic pieces 27a and 27a. 31, 31). Therefore, in the case of this example, the forward displacement of the coupling bracket 24 with respect to the rear end portion of the push-pull rod 22 significantly increases the impact applied to the driver's body colliding with the steering wheel 1. It can be performed smoothly without generating a large resistance.

  Further, as the coupling bracket 24 is displaced forward with respect to the push / pull rod 22, the distal end surfaces of the elastic pieces 27 a and 27 b handle the outer peripheral surface of the push / pull rod 22. Also at this time, the grease held in the valleys between the elastic pieces 27a and 27a is applied to the tip surfaces (flat surface portions 31 and 31) of the elastic pieces 27a and 27a and the push-pull rod 22 It can be efficiently supplied to the rubbing surface with the rear end portion or the intermediate portion outer peripheral surface (outer flat surfaces 33, 33 described later). In the case of this example, the elastic pieces 27b, 27b formed on the curved plate portions 29, 29 can also ensure the coaxiality between the push-pull rod 22 and the insertion hole 32. . For this reason, in the case of this example, the forward displacement of the coupling bracket 24 can be performed smoothly, and the desired resistance is exerted on each of the elastic pieces 27a and 27b, so that the desired shock absorbing function can be achieved. Can be obtained. Therefore, the steering wheel 1 can be smoothly displaced from the state shown in FIG. 1 to the state shown in FIG. As a result, the impact applied to the body of the driver colliding with the steering wheel 1 can be reduced, and the protection of the driver can be enhanced. In the case of this example, unlike the conventional structure shown in FIG. 17 described above, the push-pull rod does not need to be divided into two parts, so that the quietness at the time of adjusting the position of the steering wheel 1 can be secured.

  In the case of this example, as described above, since the lubricant can be sufficiently supplied to the friction surface (sliding contact surface), the flat surface portions 31 and 31 provided on the front end surfaces of the respective elastic pieces 27a and 27a. Relative displacement can be performed smoothly regardless of the presence of In addition, the provision of these flat surface portions 31, 31 ensures a sufficient contact area with the pair of outer flat surfaces 33, 33 formed on the outer peripheral surface of the push-pull rod 22, in a normal state. This is advantageous in terms of suppressing rattling between the push-pull rod 22 and the coupling bracket 24.

In the case of this example, as described above, the case where the elastic support ring 25a shown in FIG. 4A is used as the shock absorbing member has been described. However, FIGS. It is also possible to use the elastic support rings 25b to 25e shown in FIG. In the case of each of the elastic support rings 25b to 25e, the protruding direction of all or a part of the respective elastic convex portions is opposite to the elastic support ring 25a in the radial direction. In the following, the elastic support rings 25b to 25e of these other examples will be described with a focus on their characteristic portions.
First, an elastic support ring 25b shown in FIG. 2B is formed by a pair of curved plate portions 29, 29 constituting the elastic support ring 25b, and a plurality of elastic convex portions 27c, 27c having a partially spherical convex shape. Is forming. Other parts are the same as those of the elastic support ring 25a shown in FIG. Therefore, if the elastic support ring 25b having such a configuration is used, substantially the same effect as that of the elastic support ring 25a can be obtained, and the number of the elastic pieces 27c and 27c can be increased or decreased as necessary. By doing so, the magnitude of the resistance can be set finely. Further, a large amount of lubricant can be held between the elastic convex portions 27c and 27c.

  Further, the elastic support ring 25c shown in FIG. 5C is provided with a plurality of elastic convex portions 27d and 27d which are long in the axial direction of the elastic support ring 25c only on the pair of flat plate portions 28 and 28. It is configured. In the case of the elastic support ring 25c having such a configuration, as described above, the length directions of the elastic convex portions 27d and 27d coincide with the displacement direction, which is disadvantageous from the viewpoint of securing the lubricant. There is a possibility. However, when the elastic support ring 25c is used in a portion where the lubrication conditions are not strict (for example, a portion where the relative displacement is small, or a portion where the coupling strength is not so much required), it is easy to use the elastic support ring 25c. The configuration is advantageous in terms of manufacturing costs. Also, when the elastic support ring 25c is made of brass or the like having excellent self-lubricating properties, it is advantageous in that the processing cost can be reduced compared to the elastic support rings 25a and 25b described above.

  Further, the elastic support ring 25d shown in (D) of the same figure shows the direction of the elastic convex portions 27d and 27d formed on the elastic support ring 25c shown in (C) of the same figure with respect to the axial direction. The elastic projections 27e and 27e are inclined at a predetermined angle (for example, about 70 degrees). Also in the case of the elastic support ring 25d having such a configuration, as in the case of the elastic support ring 25c described above, it is advantageous in terms of manufacturing cost and the like, and the lubricant is more advantageous than the elastic support ring 25c. It becomes easy to secure.

  Further, the elastic support ring 25e shown in FIG. 5E has a configuration in which a pair of flat plate portions 28, 28 are provided with a plurality of partially spherical elastic convex portions 27f, 27f. In the illustrated example, the elastic convex portions 27f and 27f are irregularly arranged. However, the elastic convex portions 27f and 27f may be arranged regularly (for example, in a staggered manner). In the case of the elastic support ring 25e having such a configuration, the size of the resistance can be set finely by changing the number and height of the elastic convex portions 27f and 27f. A large amount of lubricant can be secured between the elastic convex portions 27f and 27f.

  When the elastic support rings 25a to 25e shown in FIGS. 4A to 4E are directly incorporated between the push-pull rod 22 and the insertion hole 32, these elastic support rings 25b are used. ˜25e are fitted on the outer peripheral surface of the push-pull rod 22 near the rear end of the intermediate part. In this case, as shown in FIG. 7, in order to prevent the elastic support rings 25b to 25e from shifting in the axial direction of the push-pull rod 22, the rear end of the intermediate portion of the push-pull rod 22 is used. Locking grooves 34 for externally fitting the elastic support rings 25a to 25e can be formed on the outer peripheral surface of the shift portion over the entire circumference. However, in order to obtain the impact absorbing performance by the elastic support rings 25a to 25e in the entire stroke range of the push-pull rod 22 and the coupling bracket 24, as shown in FIGS. The elastic support rings 25a to 25e are preferably locked inside the 24 insertion holes 32. Further, in any of the elastic support rings 25a to 25e, the elastic convex portions 27a to 27e may be formed so as to protrude to the outer peripheral surface side or to protrude to the inner peripheral side. May be formed in a state of alternately projecting between the outer peripheral surface side and the inner peripheral surface side between the adjacent elastic convex portions.

[Second Example of Embodiment]
FIG. 8 shows a second example of the embodiment of the present invention, which also corresponds to claims 1-8. The feature of this example is that the rear end portion (the right end portion in FIG. 8) of the push-pull rod 22a and the coupling bracket 24a are coupled via a cylindrical coupling member 35. That is, the push-pull rod 22 (see FIGS. 1 and 2, etc.) used in the first example of the above-described embodiment is connected to the push-pull rod 22a having a shorter overall length than the push-pull rod 22 and the connecting member 35. The structure is divided into two. An insertion hole 32a through which the push-pull rod 22a can be inserted is formed on the inner side of the connecting member 35 in the axial direction. The opening end of the insertion hole 32a has a larger inner diameter than the insertion hole 32a. An engaging groove 34a is formed. Also in this example, the cross-sectional shape of the outer peripheral surface of the push-pull rod 22a and the cross-sectional shape of the inner peripheral surface of the insertion hole 32a (and the locking groove 34a) are oblong. The connecting member 35 having such a configuration can be used by cutting a long drawing tube having the same cross-sectional shape over the entire length into a desired length. In addition to the drawing process, it can be formed by pressing, hydroforming, or the like. In this case, the portion having the curvature (the portion facing the curved plate portions 29 and 29) can be processed with high accuracy by machining such as cutting. The portion machined with high accuracy as described above is used as a stopper portion for positioning in the axial direction by engaging with a part of the elastic support rings 25a to 25e when the elastic support rings 25a to 25e are mounted. May function.

Also in the case of this example having the above-described configuration, any of the elastic support rings 25a to 25e as shown in the first example of the above-described embodiment can be used as the impact absorbing member. That is, in the case of this example, each of these elastic support rings 25a to 25e is used by being fitted into the engaging groove 34a formed inside the connecting member 35. Also in the case of this example having such a configuration, at the time of a secondary collision, the elastic convex portions 27a to 27f constituting the elastic support rings 25a to 25e and the rear end portion of the push / pull rod 22a are provided. The resistance (frictional force) between the outer peripheral surface and the intermediate portion causes resistance to the steering wheel 1 being displaced forward, and can effectively absorb the impact load applied to the driver's body. In the case of this example, when the push-pull rod 22a and the connecting member 35 contract, the rear end portion or intermediate portion of the push-pull rod 22a can be stored in the insertion hole 32a. it can. Therefore, the rear end portion of the push-pull rod 22a is prevented from projecting to the driver side, which is advantageous in terms of enhancing driver protection.
Other configurations and operations including the structure and operation related to the steering wheel front-rear position adjusting device are the same as those in the first example of the embodiment described above.

[Third example of embodiment]
FIGS. 9-11 has shown the 3rd example of embodiment of this invention corresponding to Claims 1-7, 9. FIG. The feature of this example is that an elastic support ring is incorporated between the outer column 5b and the inner column 6b constituting the steering column 4b, and the outer column 5b and the inner column 6b are connected to be extendable (shrinkable). is there.

  For this reason, in the case of this example, between the inner peripheral surface of the rear end portion (right end portion in FIG. 9) of the outer column 5b supported with respect to the vehicle body and the outer peripheral surface of the intermediate portion of the inner column 6b. Any one of the elastic support rings 25a to 25e described above is sandwiched with the outer diameter reduced. 10 to 11 show a state in which the elastic support ring 25c is incorporated. Moreover, in the case of this example, the flange part 36 which protrudes to radial direction outward is provided in the one end opening outer periphery of each said elastic support ring 25a-25e. Then, as shown in FIG. 10, the flange 36 is locked to the rear edge of the outer column 5b in a state in which the elastic support rings 25a to 25e are assembled between the peripheral surfaces. is doing. Accordingly, the elastic support rings 25a to 25e can be prevented from being displaced forward with respect to the outer column 5b. As a result, in the case of this example, it is not necessary to form locking grooves or the like for locking the elastic support rings 25a to 25e on the inner peripheral surface of the outer column 5b, thereby reducing the manufacturing cost. Can be planned.

  The structure of this example is associated with a collision accident by using the elastic support rings 25a to 25e as shock absorbing members, as in the case of the structures of the first and second examples of the embodiment described above. It can be used to absorb the impact applied to the steering wheel 1 from the driver's body during a secondary collision. In this case, since the steering column 4b can be contracted while absorbing the impact load applied from the driver's body at the time of the secondary collision, the steering column can be removed from the fixed part such as the dashboard at the time of the collision. No need to drop off. Therefore, the relationship between the steering wheel 1 and the driver's body is not deviated, and it is not only easy to secure the function of the airbag device, but also the collision between the driver's feet, waist, etc. and the components of the steering device. This is also advantageous from the standpoint of preventing the above. In this case, the steering shaft 2a rotatably supported inside the inner column 6b also adopts a configuration in which the overall length is reduced by providing an expansion / contraction part (not shown) in the intermediate part. Of course. For example, the steering shaft 2a may be divided into two parts, a circular outer shaft and a solid rod-shaped inner shaft, and the elastic support rings 25a to 25e may be assembled to the joint portion between the two shafts.

Further, in the case of the structure of this example, it is used in combination with, for example, an electric or manual front / rear position adjusting device (not shown), and the elastic support rings 25a to 25e are used to extend and retract the steering column 4b. It can also be used to suppress sticking. That is, by using the elastic support rings 25a to 25e, a desired resistance is applied between the inner peripheral surface of the outer column 5b and the outer peripheral surface of the inner column 6b, and both the columns 5b are provided. , 6b can be prevented from rattling, and the coaxiality of both the columns 5b and 6b can be easily achieved. Therefore, the inner column 6b can be smoothly displaced in the front-rear direction with respect to the outer column 5b fixed to the vehicle body. In this case, since it is not necessary to increase the processing accuracy of the inner peripheral surface of the outer column 5b and the outer peripheral surface of the inner column 6b, it is possible to reduce the processing cost.
In addition, the magnitude | size of the resistance provided between the inner peripheral surface of the said outer column 5b and the outer peripheral surface of the said inner column 6b by each said elastic support rings 25a-25e is this inner column 6b with respect to this outer column 5b. The degree of displacement in the front-rear direction is acceptable.
Moreover, the structure of this example can also be used in combination with a steering wheel longitudinal position adjusting device.
Other configurations and operations are the same as those of the first example of the embodiment described above.

  The present invention is not limited to the above-described steering wheel front / rear position adjusting device, but can be used in combination with a steering wheel vertical position adjusting device called a tilt type steering device. The steering wheel vertical position adjusting device will be described below with reference to FIGS. In the case of the illustrated example, the steering column 4c supports its front end portion (left end portion in FIG. 12) in a swingable manner around a tilt pivot shaft 37 that is supported in a horizontal direction with respect to a vehicle body (not shown). . Further, the rear end portion (right end portion in FIG. 12) and the intermediate portion of the steering column 4c are supported on the vehicle body by a vehicle body side bracket 38 fixed to the vehicle body, and one end side of the vehicle body side bracket 38 in the width direction. The case 40 of the electric motor 39 is fixed to the lower end portion (front side of FIG. 12). A housing portion 41 is provided on the front side of the case 40 (left side in FIG. 12). The housing portion 41 is provided with a concave hole 42 opened downward, and a worm shaft 44 constituting the worm speed reducer 43 is rotatably supported in the concave hole 42. One end (the left end in FIG. 14) of the worm shaft 44 and the end of the rotating shaft 45 of the electric motor 39 are freely coupled to each other by a spline engaging portion or the like.

  Further, the upper and lower ends of the screw shaft 46 can be freely rotated by a pair of ball bearings 47a and 47b on one end in the width direction of the vehicle body side bracket 38 (right end in FIG. 13) and the housing 41. I support it. Further, a worm wheel 48 constituting the worm speed reducer 43 is externally fitted and fixed to a lower portion of the screw shaft 46 at a position higher than a portion where the ball bearing 47b disposed below is externally fitted. ing. The worm wheel 48 is engaged with the worm of the worm shaft 44. Further, a moving member 49 is fitted on the middle portion of the screw shaft 46. The moving member 49 includes a nut holder 50 and a nut member 51, and a base end portion of the connecting shaft 52 is fixed to a side wall portion of the nut holder 50. A portion closer to the tip of the connecting shaft 52 is rotatably inserted and supported in a support hole 53 provided at one end in the width direction of the steering column 4c. The central axis of the connecting shaft 52 is arranged in parallel with the tilt pivot shaft 37.

  In the case of the illustrated structure having such a configuration, the screw shaft 46 supported by the vehicle body side bracket 38, the electric motor 39, the moving member 49 supported by the steering column 4c, the screw shaft 46 and the electric motor. The electric actuator is constituted by the worm speed reducer 43 provided between the motor 39 and the worm reducer 43. The electric actuator moves the nut member 51 in the axial direction of the screw shaft 46 with respect to the screw shaft 46 as the electric motor 39 is driven. The nut member 51 and the screw shaft 46 constitute a feed screw mechanism 54. In order to move a steering wheel (not shown) to a desired height position, the electric motor 39 is energized, and the rotating shaft 45 of the electric motor 39 is rotated, whereby the worm shaft 44 and the worm wheel 48 are rotated. Then, the screw shaft 46 is rotated, and the nut member 51 is moved in either the upper or lower direction along the screw shaft 46. As a result, the steering column 4c can be moved in an arc (oscillating) around the tilt pivot shaft 37. In the case of the illustrated example, the displacement generated between the vertical motion of the nut member 51 and the circular motion of the steering column 4c is a relative displacement in the length direction between the nut member 51 and the nut holder 50. Further, the nut holder 50 is rotated by the rotation of the nut column 50 with respect to the steering column 4c, thereby realizing a smooth swing of the steering column 4c.

  In the case of the telescopic steering device combined with the tilt type steering device as described above, the push-pull rod 22 is displaced in the axial direction by another electric motor, and the inner column 6a is displaced in the front-rear direction via the coupling bracket 24. Yes. With regard to such a telescopic steering device combined with a tilt type steering device, a secondary portion can be obtained by incorporating the elastic support rings 25a to 25e as described above into the coupling portion between the push-pull rod 22 and the coupling bracket 24. Effective shock absorption performance in the event of a collision can be exhibited.

In each of the above-described examples, the shock absorbing member of the present invention has been described as being incorporated into a steering device. As long as it is a coupling part that enables relative displacement in the axial direction, it can also be used, for example, as an expansion / contraction part of a drive shaft. It can also be used by being incorporated in the middle of the transmission shaft constituting the automobile steering system.
In addition, about the structure of each elastic convex part which comprises the said impact-absorbing member, not only the structure shown to (A)-(E) of FIG. 4 mentioned above but the structure which combined these may be employ | adopted. it can.

The principal part vertical side view which shows the 1st example of embodiment of this invention in the state of normal time. Similarly, the main part vertical side view showing a secondary collision occurred The expanded AA sectional view of FIG. The perspective view which shows another 5 examples of the elastic support ring which can be similarly used for this example. The schematic diagram similarly shown in the state which looked at the elastic support ring from the axial direction end surface side. The schematic diagram which shows the other shape of the slit part which can be employ | adopted similarly in the state seen from the left of FIG. The principal part perspective view of a push-pull rod similarly. The principal part vertical side view which shows the 2nd example of embodiment of this invention. The principal part vertical side view which shows the 3rd example. The B section enlarged view of FIG. CC sectional view of FIG. The side view which shows an example of the tilt type steering apparatus which can be implemented in combination with this invention. FIG. 13 is an enlarged DD cross-sectional view of FIG. 12. EE sectional drawing of FIG. 13 which abbreviate | omits and shows a part. The perspective view which shows the motor vehicle front part which incorporated the steering device with an electric position adjustment mechanism. The partial schematic side view which shows an example of the steering apparatus with an electrically-driven position adjustment mechanism known conventionally. The partial cut | disconnection rough side view of the adjustment screw rod which can be shrunk at the time of a secondary collision. The perspective view of a limit ring conventionally known as a torque limiter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Steering wheel 2, 2a Steering shaft 3 Steering wheel 4, 4a, 4b, 4c Steering column 5, 5a, 5b Outer column 6, 6a, 6b Inner column 7 Support plate 8, 8a Adjustment screw rod 9 Male screw part 10 Housing 11 Outside Tube 12 Inner shaft 13 Pin 14 Limit ring 15 Body portion 16 Convex portion 17 Outer shaft 18 Inner shaft 19 Rolling bearing 20 Feed screw mechanism 21 Feed nut 22 Push-pull rod 23 Housing 24, 24a Coupling brackets 25a-25e Elastic support ring 26 Body Part 27a-27e Elastic convex part 28 Flat part 29 Curved plate part 30 Slit part 31 Flat surface part 32, 32a Insertion hole 33 Outer plane 34, 34a Locking groove 35 Connecting member 36 Elevation part 37 Tilt pipette shaft 38 Car body side bra 39 Electric motor 40 Case 41 Housing part 42 Concave hole 43 Worm speed reducer 44 Worm shaft 45 Rotating shaft 46 Screw shaft 47a, 47b Ball bearing 48 Warm wheel 49 Moving member 50 Nut holder 51 Nut member 52 Connecting shaft 53 Support hole 54 Feed screw mechanism

Claims (9)

  An elastic metal plate is formed by bending, and includes a cylindrical main body portion and a plurality of elastic convex portions formed so as to protrude from the surface of the main body portion. The shaft member and the mating member having the insertion hole are clamped between the inner peripheral surface of the insertion hole through which the member can be inserted in a state where the dimension in the radial direction is elastically compressed. An elastic support ring that couples relative displacements in the direction, and the main body is formed of a pair of flat plates arranged substantially parallel to each other in a state of being separated from each other, and both ends of both flat plates in the width direction. A pair of connecting portions provided in a continuous portion, and each elastic convex portion is formed on at least one flat plate portion so as to be capable of elastic deformation in the front and back direction of the flat plate portion. Elastic support ring.   The elastic support according to claim 1, wherein a slit portion corresponding to a gap existing between both longitudinal edges of the metal plate is provided in any part of both the flat plate portions and the both connecting portions. ring.   The plurality of elastic convex portions formed on the flat plate portion each have a shape that is long in the width direction of the flat plate portion and coincides with the axial direction of the shaft member. The elastic support ring described in the item.   The plurality of elastic convex portions formed on the flat plate portion each have a shape that is long in a direction perpendicular to the width direction of the flat plate portion. Elastic support ring.   The elastic support ring according to claim 1, wherein each of the plurality of elastic convex portions formed on the flat plate portion has a substantially circular planar shape.   The elastic support ring described in any one of Claims 1-5 which has formed the elastic convex part in the connection part.   The elastic support ring absorbs the energy of this impact only when an impact load exceeding a predetermined value is applied between the shaft member and the counterpart member, and the shaft of the shaft member and the counterpart member is absorbed. The elastic support ring according to any one of claims 1 to 6, wherein the elastic support ring is a shock absorbing member that allows relative displacement in a direction.   A steering column that rotatably supports a steering shaft inside, a driven member coupled to a part of the steering column, a push-pull rod disposed in the axial direction of the steering column, and a push-pull rod A coupling member in which one end portion and the driven member are detachably coupled to each other, and is rotatably supported around a portion near the other end of the push-pull rod, and the push-pull rod is attached to the steering column with rotation. A steering member that is displaced in the axial direction; and an electric motor for rotationally driving the driving member; and the steering column based on relative displacement between the driving member and the push-pull rod based on energization of the electric motor. And the position of the steering wheel supported by the end of the steering shaft is adjustable, In the steering apparatus configured so that the coupling portion between the push-pull rod and the driven member can be separated based on an impact load applied to the steering wheel at the time of a collision, the coupling member is described in claim 7. A steering device characterized by being an elastic support ring. The steering device which has couple | bonded the inner column and outer column which comprise a steering column with the elastic support ring in any one of Claims 1-7.

Images