JPH11208486A - Rack-and-pinion type steering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate necessity for keeping in stock a number of component parts out of installation in place, which is otherwise required to alter the stroke of the rack of a rack-and-pinion type steering device. SOLUTION: A rack-and-pinion type steering device 1 is structured so that a rack stopper 21 at the end of a pinion housing 2 abuts to a projection 7a on a detent 7 provided at the end of a rack so as to restrict the stroke of the rack 3. The detent 7 is held pinchedly by the rack 3 and a joint housing 41 of a ball joint 4 and is located accurately about the axial direction of the rack 3. The stroke of the rack 3 can be altered by differing the protruding height of the projection 7a, and the detent 7 is installed approx. at the final stage of the assembly process. This allows easily working well with different strokes, and the management costs can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rack and pinion type steering device. In particular, the present invention relates to a configuration for varying the stroke of a rack shaft.

[0002]

2. Description of the Related Art Conventionally, rack and pinion type steering devices of a plurality of types having different strokes according to the type of vehicle using the same have been manufactured. In the manufacture of a plurality of such models, most of the parts are shared and assembled as semi-finished units that can be shared, thereby reducing the inventory of finished products.

In a rack-and-pinion type steering apparatus, a joint housing of a universal joint that connects an end of a rack shaft and a tie rod is connected to a fixed-side rack stopper disposed at an end of a pinion housing that supports a center portion of the rack shaft. It is configured to contact with the movement of the rack shaft to regulate the stroke. By the way, it is necessary to set various things as a stroke amount of the rack shaft due to a difference in regulation of each vehicle type or the like. Therefore, when manufacturing according to different strokes, first, a plurality of rack stoppers having different axial lengths are prepared, and rack stoppers having specifications corresponding to the strokes are assembled to the pinion housing. Thereafter, a rack shaft is assembled to the pinion housing, and a ball joint or the like is attached to an end of the rack shaft, so that the rack and pinion type steering device is almost completed. As described above, the stroke amount is adjusted by changing the specification of the rack stopper attached in the middle of the assembly process.

[0004]

However, since the rack stopper attached in the middle of the assembling process is used for changing the stroke amount, in order to cope with the build-to-order manufacturing, the parts to be attached in the middle and subsequent stages are not needed. The semi-finished unit will be kept in stock without being assembled. For this reason, the number of items of production management and inventory management in the assembling process has increased, and management has been troublesome. As a result, the cost was increased.

Accordingly, an object of the present invention is to solve the above-mentioned technical problems, to reduce the management cost by assembling in a substantially completed state, and to provide a rack-and-pinion type steering apparatus having a configuration capable of coping with different strokes. It is to provide.

[0006]

According to a first aspect of the present invention, there is provided a rack and pinion type steering apparatus comprising: an end portion of a rack shaft which is inserted into and out of a pinion housing; In a rack and pinion type steering device in which the joint housing and the joint housing are screwed together with a rotation preventing member for regulating relative rotation therebetween, in the rack and pinion type steering device, a member fixed to an end of the pinion housing is in contact with the rotation preventing member. It is characterized in that a protruding portion for restricting the stroke amount of the rack shaft is provided in contact therewith.

According to this configuration, the following operation is achieved.
That is, the stroke of the rack shaft is varied by changing the height of the convex portion provided on the rotation preventing member, clamping the rotation preventing member, and screw-fastening the end of the rack shaft and the joint housing. be able to. in this way,
The detent member, which can be attached almost at the end of the assembly process, can have a function to vary the stroke amount, so the rack and pinion type steering device can be used as an assembled product to handle multiple stroke amounts. Can be stocked in close form. As a result, the number of unassembled parts can be reduced, and the number of inventory management points in the assembling process can be reduced, resulting in easier management.

In addition, the detent member for varying the stroke amount is reliably positioned in the rack axis direction by being sandwiched between the end of the rack shaft and the joint housing, so that the stroke amount can be accurately determined. Can be set to According to a second aspect of the present invention, there is provided a rack and pinion type steering device according to the first aspect, wherein the detent member comprises a washer integrally formed with a convex portion.

According to this configuration, the following operation is achieved in addition to the operation of the first aspect of the invention. That is, since the projection is integral with the washer, it is possible to prevent an increase in the number of parts. For example, a plurality of specifications having different heights of the convex portions can be manufactured at low cost by cold forging.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a front view showing a schematic configuration of a main part of a rack and pinion type steering apparatus according to an embodiment of the present invention. Rack and pinion steering device 1
Is a pinion that rotates in conjunction with the handle (not shown)
And a pinion housing 2 for accommodating the pinion;
A rack shaft 3 on which a rack engaging with the pinion is formed;
It has a tie rod 5 connected to an end of the rack shaft 3 via a ball joint 4. The tie rod 5 is connected to a steered wheel via a knuckle arm (not shown) or the like. The base of the tie rod 6, the projecting portions of the ball joint 4 and the rack shaft 3 are covered with the rubber boot 6.
Is fixed to the pinion housing 2. The center of the rack shaft 3 is supported by the pinion housing 2 so as to be movable in the axial direction. When the handle is operated, the pinion rotates, and the rack shaft 3 meshing with the pinion moves in the axial direction to steer the steered wheels.

The rack and pinion type steering device 1 includes a rack stopper 21 provided at an end of the pinion housing 2.
And the protrusion 7a of the rotation preventing washer 7 provided at the end of the rack shaft 3 abuts on each other, thereby regulating the stroke amount of the rack shaft 3. In the rack-and-pinion type steering device 1, both ends of the rack shaft 3 are substantially similar to each other. In the following, the description will focus on one end.

The details will be described below. The pinion housing 2 is a cylindrical member, through which the rack shaft 3 is inserted. A bush 24 slidably supporting the rack shaft 3, an oil seal 23, and a rack stopper 21 are arranged at the end of the pinion housing 2 in order from the inside to the outside.

The rack stopper 21 is a cylindrical member, through which the rack shaft 3 is inserted. The outer peripheral surface of the rack stopper 21 is fixed to the outside of the inner peripheral surface of the pinion housing 2 by a retaining ring 22. Rack axis 3
Is a hollow shaft having a rack formed on the outer peripheral surface thereof as described above, and supported by the bush 24.
The end of the rack shaft 3 is inserted through the inside of the pinion housing 2 so as to be able to enter and exit freely.
1a. A joint housing 41 of the ball joint 4 is fixed to an end of the rack shaft 3.

The ball joint 4 includes a joint housing 41 having a concave portion, a spherical seat 43 including a plurality of members provided in the concave portion of the joint housing 41,
Ball 4 slidably supported by this spherical seat 43
2 is provided. The ball 42 is formed integrally with one end of the tie rod 5 and is housed in a recess of the joint housing 41.

The recess of the joint housing 41 is open to one side, from which the tie rod 5 extends. Further, a shaft 44 is provided on the surface of the joint housing 41 opposite to the side where the tie rod 5 extends. The shaft 44 has an external thread, which is
The anti-rotation washer 7 is inserted and screwed into a female screw formed at the end of the rack shaft 3.

The detent washer 7 is a steel washer and is formed in a disk shape having a hole in the center. The detent washer 7 is sandwiched between the joint housing 41 and the end surface of the rack shaft 3. The detent washer 7 includes an annular main body 7m and a protrusion 7 protruding from one surface of the main body 7m.
a, a first engaging claw 7b on the inner peripheral edge of the main body 7m and protruding on one surface side, a second engaging claw 7c on the outer peripheral edge of the main body 7m and protruding on the other surface side, It has.
The detent washer 7 is attached with one surface of the main portion 7m (the surface on the side where the convex portion 7a is located) facing the rack shaft 3 side.

The first engaging claws 7b are provided in a pair, each of which engages with the groove 3b at the end of the rack shaft 3. Also, the second engagement claws 7c are provided as a pair, and
Is fixed between the rack shaft 3 and the joint housing 41, and the second engaging claw 7c is bent and raised. The pair of second engagement claws 7c are engaged with the outer peripheral surface of the joint housing 41 in a fitted state. in this way,
The rotation stopper 7 regulates relative rotation between the joint housing 41 and the rack shaft 3.

The projection 7a is formed integrally with the main body 7m. The convex portion 7a is formed in an annular shape so as to avoid the end of the rack shaft 3. The top of the projection 7a is
The rack stopper 21 can be brought into contact with the outer end surface 21a. The convex portion 7a has a predetermined protruding height along the axial direction of the rack shaft 3 from the main body portion 7m contacting the end of the rack shaft 3, and the protruding height is set according to the stroke amount. I have.

The shape of the projection 7a is not limited to the above-mentioned annular shape. For example, the shape may be an annular shape in which a part is missing or a sector shape. In short, it may be arranged at a position where it comes into contact with the rack stopper 21. Further, the convex portion 7a may be formed separately from the main portion 7m of the detent washer 7 and joined to each other. The stroke amount of the rack shaft 3 in the rack and pinion type steering device 1 is determined as follows. That is, the rack shaft 3 is moved by the handle operation from the state in which the convex portion 7a of the detent washer 7 at one end of the rack shaft 3 comes into contact with the rack stopper 21 opposed thereto. The travel distance of the rack shaft 3 until the protrusion 7a of the detent washer 7 at the other end comes into contact with the rack stopper 21 opposed thereto is the stroke amount.

To change the stroke amount, the rack shaft 3
The protrusion heights of the protrusions 7a of at least one of the detent washers 7 among the both end portions may be made different. For example, the stroke amount can be further shortened by using the detent washer 7 having the projection 7a having a higher protruding height. In addition, the stroke amount can be further lengthened by reducing the protruding height of the convex portion 7a.

In the case where the rack and pinion type steering apparatus 1 having a different stroke amount is manufactured while most parts are shared, the following can be performed. A detent washer 7 having projections 7a having different protruding heights is prepared in advance. This detent washer 7 can be easily formed by cold forging of steel or the like. Pinion housing 2
Then, a rack stopper 21 and the like are assembled, and the rack shaft 3 is inserted into the rack stopper 21 to assemble it into a shape close to an assembled product. Also, the tie rod 5 and the ball joint 4 are assembled.

At this time, when the stroke amount is changed by changing the projection 7a of one of the rotation preventing washers 7 of the rack shaft 3, the tie rod 5 and the like on the other side are assembled to the rack shaft 3. You may leave. These assembled products are kept in stock, and when necessary, the end of the rack shaft 3 and the joint housing 41 are screwed together by holding the detent washer 7 having the convex portion 7a having a predetermined projecting height. I do. Bends and raises the second engaging claw 7c of the detent washer 7,
By attaching the rubber boot 6 and the like, the rack and pinion type steering device 1 having a desired stroke amount can be completed.

As described above, according to the present embodiment, the detent washer 7 between the end of the rack shaft 3 and the joint housing 41 of the ball joint 4 is provided with the convex portion for regulating the stroke of the rack shaft 3. With the provision of 7a, the detent washer 7 that can be attached almost at the end of the assembling process can be provided with a function for varying the stroke amount. The pinion type steering device 1 can be stocked in a form close to an assembled product. As a result, the number of unassembled parts can be reduced, and the number of inventory management points in the assembling process can be reduced. As a result, the management becomes easier and the management cost can be reduced.

The non-turn washer 7 for varying the stroke amount is sandwiched between the end of the rack shaft 3 and the joint housing 41 so that the rack shaft 3
, The stroke amount can be accurately set. In particular, detent washer 7
Is a member which is screwed and fixed with a detent, so that even if an impact is applied, it does not loosen and the stroke amount can be accurately maintained.

Since the rotation preventing washer 7 is formed integrally with the projection 7a, it is possible to prevent an increase in the number of parts due to the provision of the projection 7a. For example, a plurality of specifications having different heights of the protrusions 7a can be manufactured at low cost by cold forging. In the above-described embodiment, the rack stopper 21 is provided as a member that regulates the stroke amount. However, the present invention is not limited to this.
The member that regulates the stroke amount may be a member that is provided at the end of the pinion housing 2 and that can abut on the above-described detent washer 7.

The method for making the protrusion height of the projection 7a of the detent washer 7 different is not particularly limited. For example, a non-turn washer 7 having a protrusion 7a having a protrusion height that can be used as a change amount of the stroke amount is prepared, and the protrusion 7a is formed on the protrusion 7a so that the protrusion height of the protrusion 7a is reduced. Cutting, plastic working, or the like may be performed. In addition, various design changes can be made without changing the gist of the present invention.

[0027]

According to the first aspect of the present invention, the following effects can be obtained. In other words, by providing the rotation preventing member sandwiched between the rack shaft and the joint housing with the convex portion that regulates the stroke amount of the rack shaft, if the rotation amount of the rotation preventing member that can be attached almost at the end of the assembly process is different. In order to cope with a plurality of stroke amounts, the rack and pinion type steering device can be stocked in a form close to the assembled product.
As a result, the number of unassembled parts can be reduced, and the number of inventory management points in the assembling process can be reduced, resulting in easier management. Further, since the rotation preventing member is reliably positioned in the rack axis direction, the stroke amount can be accurately set.

According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, an increase in the number of parts can be prevented by integrally forming the convex portion on the detent member.

[Brief description of the drawings]

FIG. 1 is a front view showing a schematic configuration of a main part of a rack and pinion type steering device according to an embodiment of the present invention.

FIG. 2 is a view of the detent washer in FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 rack and pinion type steering device 2 pinion housing 3 rack shaft 4 ball joint 7 detent washer (detent member) 7 a convex 21 rack stopper (member fixed to end) 41 joint housing

Claims (2)

[Claims] An end of a rack shaft inserted into and out of a pinion housing and a joint housing of a ball joint are screwed together with a detent member for restricting relative rotation therebetween. In the rack and pinion type steering device, a rack and pinion type steering device is provided, wherein the rotation preventing member is provided with a convex portion that abuts a member fixed to an end of a pinion housing and regulates a stroke amount of a rack shaft. . 2. The rack-and-pinion type steering apparatus according to claim 1, wherein the rotation-stopping member is made of a washer integrally formed with a convex portion.