JP2006224718A - Steering gear box for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To interrupt transmission of external force received by a housing of a steering gear box to an input side end portion of an input shaft. <P>SOLUTION: The steering gear box A1 is provided with the input shaft 11 rotated with rotations of a steering wheel, an output member 12 steering a wheel with rotations of the input shaft 11, and the housing 13 holding the input shaft 11 and the output member 12. The input shaft 11 is provided with a slider 11B (an input side rotating member) coupled so as to transmit torque, and a pinion gear shaft 11A (an output side rotating member). An outer spline 11a3 of the pinion gear shaft 11A and an inner spline 11b2 of the slider 11B are slidably fitted and coupled in the input shaft direction by external force F received by the housing at the time of collision of a vehicle, thereby constituting an external force transmission interrupting means. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a steering gear box for a vehicle.

A steering gear box for a vehicle includes an input shaft that rotates as the steering wheel rotates, and an output member that turns a wheel as the input shaft rotates, and holds the input shaft and the output member. And a housing that supports the vehicle body (see, for example, Patent Document 1).
JP-A-5-77737

  In the vehicle steering gear box described in Patent Document 1 described above, the housing is assembled so as to be movable toward the rear of the vehicle with respect to the vehicle body. For this reason, when the housing receives an external force (force toward the rear of the vehicle) during a vehicle collision, the steering gear box moves toward the rear of the vehicle. In this case, the above-described external force may be transmitted to the vehicle interior via a steering system (a power transmission system such as an intermediate shaft or a steering shaft connecting the steering gear box and the steering wheel).

  The present invention is configured so that the external force received by the housing of the steering gear box can be blocked from being transmitted to the input side end of the input shaft in the event of a vehicle collision, and the external force is transmitted to the vehicle via the steering system. It is intended to prevent transmission to the room. In order to achieve such an object, the present invention includes an input shaft that is rotated as the steering wheel rotates, and an output member that steers the steering wheel as the input shaft rotates. In a vehicle steering gear box that includes a housing that holds the output member and is supported by a vehicle body in the housing, the housing is disposed between the input side end of the input shaft and the housing at the time of a vehicle collision. Is provided with an external force transmission blocking means capable of blocking the transmission of the external force received by the input shaft to the input side end.

  In this steering gear box, external force transmission blocking means provided between the input side end portion of the input shaft and the housing blocks transmission of external force received by the housing to the input side end portion of the input shaft when the vehicle collides. For this reason, it is possible to prevent the above-mentioned external force at the time of a vehicle collision from being transmitted to the vehicle interior via the steering system, and it is possible to cope with a large external force by combining with a collision countermeasure means in the vehicle interior. Alternatively, it is possible to reduce the size and weight by simplifying the collision countermeasure means in the passenger compartment.

  In carrying out the present invention, the input shaft includes an input-side rotating member and an output-side rotating member that are coupled so as to transmit torque, and the input-side rotating member and the output-side rotating member are input by the external force. The external force transmission blocking means may be configured by being slidably fitted and connected in the axial direction. In this case, it is possible to simply configure the external force transmission blocking means by the input side rotating member and the output side rotating member of the input shaft.

  In this case, the connecting member that defines the fitting connection strength between the input side rotating member and the output side rotating member (specifies the sliding start load, sliding resistance, etc. in the input shaft direction). It is also possible to provide. In this case, it is possible to appropriately control the sliding (operation) of the output side rotating member in the input shaft direction with respect to the input side rotating member by appropriately setting the material and shape of the connecting member.

  In carrying out the present invention, the input shaft is supported by the housing via a bearing, and the bearing can be detached from the housing in accordance with the external force and constitutes the external force transmission blocking means. Is also possible. In this steering gear box, when the vehicle collides, the bearing that supports the input shaft is detached from the housing in accordance with the external force received by the housing, thereby blocking the transmission of the external force to the input side end. For this reason, it is possible to prevent the above external force at the time of a vehicle collision from being transmitted to the vehicle interior via the steering system.

  In this case, a load absorbing member that absorbs a load when the bearing is detached from the housing may be interposed between the bearing and the housing. In this case, the detachment load when the bearing is detached from the housing can be absorbed by the load absorbing member.

  An actuator that allows the bearing to be detached from the housing according to the external force may be interposed between the bearing and the housing. In this case, it is possible to control the separation timing when the bearing is detached from the housing by the operation timing of the actuator.

  In implementing the present invention, the housing may be provided with an actuator capable of reducing the input shaft support rigidity of the housing in accordance with the external force. In this case, the separation timing and separation load when the input shaft is detached from the housing can be controlled by the operation of the actuator.

  Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment of a steering gear box according to the present invention. A steering gear box A1 of the first embodiment includes an input shaft 11 that is rotated as the steering wheel 20 rotates, The input shaft 11 includes an output member (rack bar) 12 that steers a wheel 30 (one is not shown) as the input shaft 11 rotates, and a housing 13 that holds the input shaft 11 and the output member 12. 13 is fixedly supported by a vehicle body (not shown).

  The input shaft 11 includes a pinion gear shaft 11A that is rotatably assembled to the housing 13 via a pair of bearings 14 and 15, and a cylindrical shape that is press-fitted to the input side end of the pinion gear shaft 11A with a predetermined tightening allowance. It is constituted by a slider 11B. The pinion gear shaft 11A is constituted by a pinion gear 11a1 meshing with the rack teeth 12a of the output member 12, and a shaft 11a2 coaxially and integrally formed with the pinion gear 11a1. A spline 11a3 is formed.

  The slider 11B is connected to the steering wheel 20 via an intermediate shaft and a steering main shaft (both not shown), and is connected to the intermediate shaft via a joint (not shown) so that torque can be transmitted to the outer periphery. The outer spline 11b1 is partially formed. An inner spline 11b2 that is press-fitted into the outer spline 11a3 of the pinion gear shaft 11A is formed on the inner circumference of the slider 11B over the entire length.

  By the way, in the first embodiment, on the input shaft 11, the outer spline 11a3 of the pinion gear shaft 11A and the inner spline 11b2 of the slider 11B are connected so as to be able to transmit torque, and the set value received by the housing 13 when the vehicle collides. The external force F (force acting from the front of the vehicle toward the rear of the vehicle shown in FIG. 1) is slidably fitted and connected in the axial direction of the input shaft 11, and the pinion gear shaft 11A of the external force F described above. Constitutes an external force transmission blocking means capable of blocking the transmission from the slider 11B to the slider 11B.

  In the steering gear box A1 of the first embodiment configured as described above, when the housing 13 receives an external force F greater than a set value during a vehicle collision, the outer spline 11a3 of the pinion gear shaft 11A becomes the inner spline 11b2 of the slider 11B. In contrast, the input shaft 11 slides in the axial direction of the input shaft 11, and the input shaft 11 contracts as shown in FIG. 3 to block the transmission of the external force F from the pinion gear shaft 11A to the slider 11B.

  For this reason, it is possible to prevent the external force F described above at the time of a vehicle collision from being transmitted to the vehicle interior via a steering system including an intermediate shaft and a steering main shaft, which is combined with a collision countermeasure means in the vehicle interior. Thus, it is possible to cope with a large external force, or to simplify the collision countermeasure means in the passenger compartment and to reduce the size and weight.

  4 and 5 show a second embodiment of the steering gear box according to the present invention. In the steering gear box A2 of the second embodiment, the input shaft 111 includes a cylindrical pinion gear 111A and the pinion gear 111A. The shaft 111B is press-fitted and fitted with a predetermined allowance so as to penetrate. The configuration other than the input shaft 111 of the steering gear box A2 is substantially the same as the configuration other than the input shaft 11 of the steering gear box A1 of the first embodiment. To do.

  The pinion gear 111A meshes with the rack teeth 12a of the output member 12 by tooth portions 111a1 formed on the outer periphery, and an inner spline 111a2 is formed over the entire length on the inner periphery. The shaft 111B is connected to the steering wheel 20 via an intermediate shaft and a steering main shaft (both not shown), and can transmit torque to the intermediate shaft via a joint (not shown) on the outer periphery of the upper end. An outer spline 111b1 that is connected to is partially formed. An outer spline 111b2 that is press-fitted into the inner spline 111a2 of the pinion gear 111A is formed on the outer periphery from the intermediate portion to the lower end portion of the shaft 111B.

  By the way, in the second embodiment, in the input shaft 111, the inner spline 111a2 of the pinion gear 111A and the outer spline 111b2 of the shaft 111B are connected so as to be able to transmit torque and are not less than a set value received by the housing 13 in the event of a vehicle collision. The external force F is slidably fitted and connected in the axial direction of the input shaft 111, and constitutes an external force transmission blocking means capable of blocking the transmission of the external force F from the pinion gear 111A to the shaft 111B. When the inner spline 111a2 of the pinion gear 111A and the outer spline 111b2 of the shaft 111B slide in the axial direction of the input shaft 111, the lower end portion of the shaft 111B can protrude out of the housing 13 through a through hole 13a formed in the housing 13. It is.

  In the steering gear box A2 of the second embodiment configured as described above, when the housing 13 receives an external force F greater than a set value during a vehicle collision, the inner spline 111a2 of the pinion gear 111A becomes the outer spline 111b2 of the shaft 111B. On the other hand, the input shaft 111 slides in the axial direction, and the input shaft 111 is displaced as shown in FIG. 5, thereby interrupting the transmission of the external force F from the pinion gear 111A to the shaft 111B.

  For this reason, it is possible to prevent the external force F described above at the time of a vehicle collision from being transmitted to the vehicle interior via a steering system including an intermediate shaft and a steering main shaft, which is combined with a collision countermeasure means in the vehicle interior. Thus, it is possible to cope with a large external force, or to simplify the collision countermeasure means in the passenger compartment and to reduce the size and weight.

  In each of the above-described embodiments (first and second embodiments), the pinion gear shaft 11A (output-side rotating member) and the slider 11B (input-side rotating member), the pinion gear 111A (output-side rotating member) and the shaft 111B ( The input side rotating member) is configured to be fitted with a spline, but as illustrated in FIG. 6, the input side rotating member is configured to be engaged with unevenness, or as illustrated in FIG. The pinion gear shaft 11A (output-side rotating member) and the slider 11B (input-side rotating member) are configured so as to be fitted with projections and depressions via the connecting members 11D and 111D, or as shown in FIG. 8 taking the first embodiment as an example. It is also possible to carry out by connecting the member) on the outer periphery via the connecting member 11E.

  The connecting members 11D and 111D shown in FIG. 7 and the connecting member 11E shown in FIG. 8 define the fitting connection strength of the output side rotating member with respect to the input side rotating member (sliding start load in the axial direction of the input shaft). Stipulates sliding resistance, etc.). For this reason, by appropriately setting the material and shape of the connecting members (11D, 111D, 11E), it is possible to appropriately control the sliding of the output-side rotating member with respect to the input-side rotating member in the input shaft direction. is there.

  FIGS. 9 and 10 show a third embodiment of the steering gear box according to the present invention. In the steering gear box A3 of the third embodiment, the input shaft 211 is integrally formed with a pinion gear 211a of a spur gear at an intermediate portion. And the outer spline 211b is integrally formed at the upper end. The lower bearing 15 is assembled to the housing 13 using an annular clip 216, and the input shaft 211 is supported on the housing 13 via the bearings 14 and 15.

  By the way, in this 3rd Embodiment, the clip 216 is set so that it may be fractured | ruptured by the external force F more than the setting value which the housing 13 receives at the time of a vehicle collision, and the lower bearing 15 respond | corresponds to the external force F mentioned above. Thus, the external force transmission blocking means that can be detached from the housing 13 and can block the transmission of the external force F from the housing 13 to the input shaft 211 is configured. Since the configuration other than the above is substantially the same as the configuration of the steering gear box A2 of the second embodiment, the same reference numerals are given and description thereof is omitted.

  In the steering gear box A3 of the third embodiment configured as described above, when the housing 13 receives an external force F that is equal to or greater than a set value at the time of a vehicle collision, as shown in FIG. With the movement of the input shaft 211 in the axial direction, the clip 216 is broken and the bearing 15 is detached from the housing 13, thereby blocking the transmission of the external force F to the input shaft 211.

  For this reason, it is possible to prevent the external force F described above at the time of a vehicle collision from being transmitted to the vehicle interior via a steering system including an intermediate shaft and a steering main shaft, which is combined with a collision countermeasure means in the vehicle interior. Thus, it is possible to cope with a large external force, or to simplify the collision countermeasure means in the passenger compartment and to reduce the size and weight.

  In carrying out the third embodiment, as shown in FIG. 11, an annular load absorbing member 217 that absorbs a load when the bearing 15 is detached from the housing 13 is interposed between the bearing 15 and the housing 13. It is also possible. In this case, the detachment load when the bearing 15 is detached from the housing 13 can be controlled (absorbed) by the load absorbing member 217.

  Further, in the third embodiment described above, the lower bearing 15 is configured to be assembled to the housing 13 using the clip 216. However, the steering according to the fourth embodiment shown in FIGS. Like the gear box A4, the lower bearing 15 is configured to be assembled to the housing 13 using a support pin 218a that can be moved forwards and backwards, for example, an electric actuator 218A (schematically illustrated) such as a solenoid. It is also possible to do.

  In this case, the external force F described above is electrically detected by a sensor, and the operation timing of the electric actuator 218A (retraction timing of the support pin 218a) is controlled by the electric control device based on a signal from the sensor, thereby It is possible to control the separation timing when 15 is detached from the housing 13 by the operation timing of the electric actuator 218A.

  Further, in the above-described fourth embodiment, the lower bearing 15 is configured to be assembled to the housing 13 using the support pin 218a that can move forward and backward of the electric actuator 218A. Like the steering gear box A5 of the fifth embodiment schematically shown in FIG. 6 or the steering gear box A6 of the sixth embodiment schematically shown in FIGS. The input shaft support rigidity of the housing 13 that supports 211 can be configured to be reduced by the operation of the electric actuator 218B or 218D.

  In the steering gear box A5 of the fifth embodiment shown in FIGS. 14 and 15, the housing 13 is constituted by a main housing 13A and a sub-housing 13B. The sub-housing 13B supports the input shaft 211 via the bearings 14 and 15 with the main housing 13A. The sub-housing 13B can be attached to and detached from the main housing 13A, and the electric actuator 218B can be detached from the main housing 13A. It is controlled by the support plate 218b which can be advanced and retracted.

  In the fifth embodiment, the external force F described above is electrically detected by a sensor, and the operation timing of the electric actuator 218B (retraction timing of the support plate 218b) is controlled by an electric control device based on a signal from the sensor. Thus, the detachment timing when the sub housing 13B is detached from the main housing 13A can be controlled by the operation timing of the electric actuator 218B. Thereby, the separation timing and separation load when the input shaft 211 is separated from the main housing 13A can be controlled by the operation of the electric actuator 218B.

  On the other hand, in the steering gear box A6 of the sixth embodiment shown in FIG. 16 and FIG. 17, the housing 13 has a slit 13b extending in the axial direction of the input shaft 211 and an overlapping portion 13c. The overlapping portion 13c can be fixed and released by an electric actuator 218D (including a fixing pin having a rack and a driving gear for driving the rack), and in the fixed state (the state shown in FIG. 16), the input shaft of the housing 13 The support rigidity is increased, and the input shaft support rigidity of the housing 13 is decreased in the released state (the state shown in FIG. 17). For this reason, the input shaft 211 can be tilted with respect to the housing 13 and detached.

  In the sixth embodiment, the external force F described above is electrically detected by a sensor, and the operation timing of the electric actuator 218D is controlled by an electric control device based on a signal from the sensor, whereby the input shaft of the housing 13 is supported. The timing for reducing the rigidity can be controlled by the operation timing of the electric actuator 218D. Thereby, the separation timing and separation load when the input shaft 211 is detached from the housing 13 can be controlled by the operation of the electric actuator 218D.

  In the steering gear boxes A4 to A6 of the fourth to sixth embodiments described above, the electric actuators 218A, 218B, and 218D are employed, but in the fourth to sixth embodiments, instead of the electric actuators. It is also possible to employ a hydraulic actuator (actuator that converts external force F to hydraulic pressure and then convert it to displacement) or a mechanical actuator (actuator that converts external force F to displacement). In these cases, an electric control device is not required, and a simple and inexpensive configuration can be achieved.

1 is an overall configuration diagram showing a first embodiment of a steering gear box according to the present invention. It is an expanded sectional view along line 2-2 in FIG. FIG. 3 is an operation explanatory diagram of a portion shown in FIG. 2. It is the principal part expanded sectional view which showed 2nd Embodiment of the steering gear box by this invention. FIG. 5 is an operation explanatory diagram of a portion shown in FIG. 4. It is the principal part expanded sectional view which showed the 1st connection structure employable in the connection part of the input side rotation member and output side rotation member in the input shaft of 1st Embodiment or 2nd Embodiment. It is a principal part expanded sectional view which showed the 2nd connection structure employable in the connection part of the input side rotation member and output side rotation member in the input shaft of 1st Embodiment or 2nd Embodiment. It is a principal part expanded sectional view which showed the 3rd connection structure employable in the connection part of the input side rotation member and output side rotation member in the input shaft of 1st Embodiment or 2nd Embodiment. It is the principal part expanded sectional view which showed 3rd Embodiment of the steering gear box by this invention. FIG. 10 is an operation explanatory diagram of the portion shown in FIG. 9. It is a principal part expanded sectional view which showed the deformation | transformation embodiment of 3rd Embodiment. It is a principal part expanded sectional view which showed 4th Embodiment of the steering gear box by this invention. It is action | operation explanatory drawing of the part shown in FIG. FIG. 9 is an enlarged cross-sectional view of a main part showing a fifth embodiment of a steering gear box according to the present invention. It is operation | movement explanatory drawing of the part shown in FIG. It is a principal part expanded sectional view which showed 6th Embodiment of the steering gear box by this invention. It is operation | movement explanatory drawing of the part shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Input shaft, 11A ... Pinion gear shaft (output side rotating member), 11a3 ... Outer spline, 11B ... Slider (input side rotating member), 11b2 ... Inner spline, 12 ... Output member, 12a ... Rack tooth, 13 ... Housing, 14, 15 ... Bearing, A1 ... Steering gear box, 20 ... Steering wheel, 30 ... Steering wheel

Claims (7)

  An input shaft that is rotated with the rotation of the steering wheel; an output member that steers the wheel with the rotation of the input shaft; and a housing that holds the input shaft and the output member. In a vehicle steering gear box supported by a vehicle body by a housing, an input side end portion of the input shaft of an external force received by the housing during a vehicle collision is provided between the input side end portion of the input shaft and the housing. A steering gear box for a vehicle, wherein an external force transmission blocking means capable of blocking transmission to the vehicle is provided.   2. The vehicle steering gear box according to claim 1, wherein the input shaft includes an input-side rotating member and an output-side rotating member that are coupled so as to be able to transmit torque, and the input-side rotating member and the output-side rotating member. A steering gear box for a vehicle, wherein the external force transmission blocking means is configured to be slidably fitted and connected in the input shaft direction by the external force.   The steering gear box for a vehicle according to claim 2, wherein a connecting member for defining a fitting connection strength of the input side rotating member and the output side rotating member is provided between the input side rotating member and the output side rotating member. Steering gear box for vehicles.   The steering gear box for a vehicle according to claim 1, wherein the input shaft is supported by the housing via a bearing, and the bearing is detachable from the housing in accordance with the external force, and the external force transmission blocking means. The steering gear box for vehicles characterized by comprising.   5. The vehicle steering gear box according to claim 4, wherein a load absorbing member that absorbs a load when the bearing is detached from the housing is interposed between the bearing and the housing. Steering gear box for vehicles.   5. The vehicle steering gear box according to claim 4, wherein an actuator is provided between the bearing and the housing so that the bearing can be detached from the housing according to the external force. Steering gear box for vehicles. 2. The vehicle steering gear box according to claim 1, wherein the housing is provided with an actuator capable of reducing an input shaft support rigidity of the housing according to the external force. box.

Images