JPH0564049U - Steering link device - Google Patents

Abstract

(57) [Abstract] [Purpose] Prevents eccentric assembly when locking the lock washer that is interposed between the rack and the ball joint body with a simple structure that excels in workability. [Structure] The lock washer 14 is attached to the rack 5 and the ball joint body 1 on the side of the tie rod 7 that is screwed to the rack 5.
It intervenes between 2 and. A recessed groove portion 21 having a substantially semicircular cross-section is formed in a concave shape at an end portion of the rack 5 on the connection side. The lock washer 14 is provided with a pair of anti-rotation protrusions 20a, 20b which are engaged in the groove 21 and are locked in the anti-rotation state. The anti-rotation protrusion has a curvature substantially equal to that of the concave groove on the rack side and is formed in an arc shape so as to draw a substantially hemispherical locus.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a rack and pinion type steering device, and more particularly to a steering link device obtained by improving a ball joint structure for connecting a rack and a tie rod.

[0002]

[Prior Art]

 The rack and pinion type of steering device has advantages that it is not only advantageous in terms of installation space but also in terms of steering performance, even though its structure is relatively simple, it can be made compact and lightweight. In recent years, it has been widely used in various vehicles including small vehicles.

An example thereof will be briefly described using the rack and pinion type steering device 1 for manual steering shown in FIG. 5. In FIG. 2, reference numeral 2 is a steering shaft extending from a steering handle (not shown), The tip of the rack is fitted into a steering body indicated by reference numeral 3, and a pinion provided at the tip of the rack constitutes a steering link device 4 which is horizontally mounted between steering wheels (not shown) of the vehicle. It is meshed with 5 rack teeth 5a.

In the figure, 6 is a king pin provided at both ends of the steering link device 4 and continuously provided on the pitman arm side of the steered wheels, and 7 is a tie rod connected to this, tie rods 7 on both the left and right sides. The racks 5 are provided in series with the rack 5 interposed therebetween. Reference numeral 8 is a tubular housing integrally formed with the steering body 3 so as to surround the steering link device 4, and is provided with mounting brackets 9a, 9b and the like to be assembled on the vehicle side, and both ends thereof. Bellows-like elastic cylindrical bodies (boots) 8a, 8b are arranged between the side and the tie rod 7 so as to secure the sealing performance from the portions.

By the way, in the steering apparatus 1 having the above-described configuration, the rack 5 and the tie rod 7 are connected via the ball joint 10 and integrally slide in the longitudinal direction by the steering operation described above. It is configured like this. Then, in the conventional steering link device 4, the connecting portion by the ball joint 10 described above has a configuration as shown in FIG. 6 and the like.

That is, a ball joint body 12 that rotatably holds a ball 11 provided at the tip of the tie rod 7 is coupled to the end of the rack 5 via a screw portion 13, and is shown in FIG. Further, the lock washer 14 having a substantially disc shape was fixed in a state of being prevented from rotating. This is because it is difficult to securely fix the ball joint main body 12 to the rack 5 only by the above-mentioned screw connection by the screw portion 13, and there is a risk of loosening between the rack 5 and the rack 5, so that the loose It was for stopping.

Here, in the conventional lock washer 14 described above, as is apparent from FIG. 7, the engaging claws 14b and 14c serve as rotation preventing projections on one side from a part of the peripheral edge of the shaft hole 14a. It is formed of a metal plate material so as to be cut and raised to have a protruding shape, and the lock washer 14 is interposed between the rack 5 and the ball joint body 12, and the engagement therebetween. The claws 14b and 14c are engaged with the locking slit groove 15 formed at the end of the rack 5 on the connecting side to connect to the rack 5 side, and a part of the peripheral edge is connected to the ball joint body 12. Folding pieces 14d and 14e formed by bending the stepped portions 12a and 12b, which are two-sided at the side ends, are connected to the ball joint body 12 side, whereby the rack 5 and the ball joint main body are connected. The structure is such that the body 12 and the body 12 are prevented from rotating and connected.

[0008]

[Problems to be solved by the device]

 However, in the conventional lock washer 14 as described above, as apparent from FIGS. 6 and 7, the locking slit 15 formed at the end of the connecting side on the rack 5 side is bent from the peripheral edge of the shaft hole 14a. When the ball joint body 12 is screwed and connected to the rack 5 with the engaging claws 14b and 14c inserted and interposed, the rack 5 and the ball joint body 12 are concentric with each other. It was difficult to keep them in place, and there was a problem that they were assembled in an eccentric state.

In particular, such a problem is often caused by combining the above-mentioned screwing work with the rack 5 and the ball joint body 12 in a state of being placed horizontally, and moreover, such a lock washer 14 is Since the thickness of the lock washer 14 is thinner than the screw relief groove formed at the base end of the threaded portion 13 on the side of the ball joint body 12, the lock washer 14 has a diameter between the rack 5 and the ball joint body 12 due to its own weight. This is because they move out of the direction, fit in the groove partly, and are assembled in an eccentric state. This is because the locking slit groove 15 is formed so as to penetrate up to the screw hole portion, and in FIG. 6 (a), a screw is attached to the center of the ball joint body 12 shown by a in the figure. This is because there is a gap x between the portion 13 and the engaging claws 14b, 14c, etc. on the lock washer 14 side, and there is a case where the gap x is mounted with a displacement amount of this x.

Then, in the eccentric assembled state in which the center deviation causes the deviation, the peripheral portion of the lock washer 14 is bent, and the bent pieces 14d and 14e are attached to the ball joint body 12 side. When they are caulked to the stepped portions 12a and 12b of the rack and locked, a non-uniform state is not obtained, and the required locked state cannot be obtained. There is a risk of causing cracks at 14d and 14e and causing a problem of loosening of the tie rod 7.

In particular, the ball joint body 12 on the side of the tie rod 7 also functions as a stopper that restricts the movable stroke of the rack 5 and the like, and when tilted, an unbalanced load is applied to the rack 5 to hold the rack 5. There is also a problem that an abnormal noise is generated when it comes into contact with the stopper surface on the body 3 side. In order to prevent such a problem, it is necessary to pay sufficient attention to the work of assembling the rack 5 and the ball joint body 12, the work is complicated, and a reliable assembled state cannot be obtained. It was inevitable that it would cause problems.

In order to prevent the eccentric assembly due to the above-mentioned radial displacement of the lock washer 14, the engaging claws 14b and 14c of the lock washer 14 do not fall into the screw escape groove portion of the base end portion of the screw portion 13. Although it may be formed with such accuracy, it is difficult to form the engaging claws 14b and 14c with high precision due to the springback caused by bending work, and there is a problem in terms of workability. However, it cannot be said that the above-mentioned problems can be solved with certainty.

For this reason, for example, as disclosed in Japanese Utility Model Laid-Open No. 56-104623, a lock washer 14 is used as a lock part which is fitted to the outer peripheral part of the rack 5 and a detent which is bent toward the ball joint body 12 side. It is also known to use a shape having a claw portion for use, but in such a structure, it is necessary to form a tubular portion or a claw portion having a guide and a positioning function, so that it is possible to perform drawing processing or the like. It is necessary to form the lock washer, which requires high processing accuracy and the like, which results in high cost, and also when assembling, it is necessary to crimp the tubular part to the rack. There is also a problem in terms of workability, which is insufficient in practical use, and it is desirable to take some measures to eliminate these problems.

[0014]

[Means for Solving the Problems]

 In order to meet such a demand, the steering link device according to the present invention is interposed between a rack and a ball joint body on the side of a tie rod which is screwed to the rack, and a part of the steering link device rotates around the end of the rack on the connecting side. It is equipped with a lock washer that connects the rack and the ball joint body in the rotational direction by being locked in the stopped state and part of the outer peripheral edge is bent and formed on the ball joint body side and locked. A pair of anti-rotation projections, which are locked in the anti-rotation state at the end of the washer on the rack connection side, are formed to have an arc shape that draws a substantially semicircular trajectory, and the rack A concave groove portion having a substantially semicircular cross-section and having a curvature substantially equal to that of the anti-rotation protrusion is formed at the connection side end portion.

[0015]

[Action]

 According to the present invention, a pair of detent projections for preventing rotation, which are formed in an arc shape so as to draw a track of a substantially semicircular shape, in a recessed groove portion having a substantially semicircular shape in cross section of a rack end. With the lock washer in place, in this state, the ball joint body on the tie rod side is screwed to the rack, and then part of the peripheral edge of the lock washer is bent. It is connected to the ball joint body side in a non-rotating state, and these are integrally connected in the rotation direction. By this, eccentric assembly at the time of screwing the lock washer interposed between the rack and the ball joint body Can be prevented by a simple structure which is excellent in workability and cost.

[0016]

【Example】

 1 to 4 show an embodiment of a steering link device according to the present invention. In these drawings, the same or corresponding parts as those in FIG. Detailed description is omitted.

According to the present invention, the rack 5 and the ball joint body 12 on the side of the tie rod 7 which is screwed to the rack 5 are interposed, and a part of them is locked to the end of the rack 5 on the connecting side. And a lock washer 14 for connecting the rack 5 and the ball joint main body 12 in the rotational direction by being bent and formed on the ball joint main body 12 side and being locked by As shown in FIGS. 1 to 4, the pair of rotation preventing projections 20a and 20b locked in the rotation preventing state at the end of the lock washer 14 on the rack 5 connecting side has a substantially semicircular shape. A groove having a semi-circular cross section, which is formed in an arcuate shape as drawn, and which has a curvature substantially equal to that of the arcuate anti-rotation protrusions 20a, 20b at the end of the rack 5 on the connecting side. 21 is characterized in that it is formed.

Here, as is apparent from FIGS. 1 and 4, the recessed groove portion 21 having a substantially semicircular cross-section described above has a semicircular shape with a curvature R so that the screw hole on the rack 5 side is formed. It is formed straddling. Further, the arcuate anti-rotation projections 20a, 20b on the lock washer 14 side are formed to have an arcuate shape having a substantially equal curvature r which is fitted along the groove bottom of the concave groove portion 21. Has been done.

According to such a configuration, the pair of detent projections for preventing rotation having an arc shape that draws a substantially semicircular locus in the concave groove portion 21 having a substantially semicircular cross section at the end of the rack 5. By setting the lock washer 14 with the 20a and 20b engaged, the lock washer 14 is arranged so that the rotation preventing projections 20a and 20b follow the groove bottom of the concave groove portion 20 on the rack 5 side. As a result, the lock washer 14 is prevented from rotating with respect to the end of the rack 5 and is automatically centered and assembled.

Then, in this state, when the ball joint main body 12 on the tie rod 7 side is screwed and coupled to the rack 5 with the screw portion 13, the lock washer 14 is provided between the rack 5 and the ball joint main body 12 on the tie rod 7 side. Therefore, they will be set with being concentric and intervening.

Thereafter, a part of the peripheral edge portion of the lock washer 14 is bent and coupled to the ball joint body 12 side in a non-rotating state, and these are integrally coupled in the rotation direction, whereby the rack 5 and the tie rod are integrally coupled. It is possible to prevent the eccentric assembly during the screwing work of the lock washer 14 that is connected with the ball joint body 12 on the 7 side in a state in which the lock is stopped and that is interposed between the rack 5 and the ball joint body 12. Become.

In particular, in the above-described configuration, the rack 5 and the ball joint body 12, which are connected with the lock washer 14 interposed therebetween, are joined in a state of being in contact with each other while maintaining concentricity.

Here, the above-mentioned curvature r of the rotation preventing projections 20a, 20b on the lock washer 14 side and the curvature R of the semicircular concave groove portion 21 on the rack 5 side have a relation of, for example, r> R. However, it will be easily understood that by tightening the ball joint body 12 on the tie rod 7 side, the washer 14 does not move in the vertical direction, and the above-mentioned required connection state is obtained.

According to the present invention, the eccentric assembling at the time of screwing the lock washer 14 interposed between the rack 5 and the ball joint main body 12 by the above-mentioned simple assembling work is special. This can be easily and reliably prevented without performing centering alignment. Problems such as the conventional one-sided contact of the lock washer 14 such as the engaging claw and the crack of the bent portion can be solved, and the lock washer 14 It is possible to process by simple punching and the like, and at the end of the rack 5 by simple milling, which is advantageous in terms of workability and cost.

It should be noted that the present invention is not limited to the structure of the above-described embodiment, and the shape and structure of each part can be appropriately modified and changed as necessary, and various modified examples can be considered. Further, in the above-described embodiment, the case where the steering link device 4 according to the present invention is applied to the rack and pinion type steering device 1 for manual steering has been described, but the present invention is not limited to this and the power steering system is not limited thereto. Of course, it can be applied to a steering device for steering.

[0026]

[Effect of the device]

 As described above, according to the steering link device of the present invention, a concave groove portion having a substantially semicircular cross section is provided at the end of the rack to which the ball joint body on the tie rod side is screwed. And a pair of anti-rotation projections for preventing the lock washer from being engaged by being engaged with the concave groove portion, the semi-circular shape having a curvature substantially equal to the curvature on the concave groove side. Despite its simple structure, it is formed in a groove with a semi-circular cross section at the end of the rack, but with a circular arc with a curvature almost equal to this, despite the simple structure. Set the lock washer with the locking projection projecting in place, and in this state, screw the ball joint body on the tie rod side to the rack with the screw part, and then attach the lock washer to the peripheral part of the lock washer. By simply assembling the parts by bending them to the ball joint body side in a non-rotating state and connecting them integrally in the rotation direction, the lock washer screwed between the rack and the ball joint body is screwed. Eccentric assembly during work can be easily and reliably prevented, problems such as cracking of engaging claws and bent parts due to uneven contact of the lock washer can be solved, and the lock washer is simply punched. In addition, the end of the rack can be machined by a simple milling process, which has various practical advantages such as excellent workability and cost.

[Brief description of drawings]

FIG. 1 is an enlarged sectional view of an essential part of a ball joint portion showing an embodiment of a steering link device according to the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a schematic exploded perspective view illustrating an assembled state of a lock washer and a rack end according to the present invention.

FIG. 4 is an enlarged sectional view of a main part of a lock washer and a rack end.

FIG. 5 is a schematic cross-sectional view for explaining a schematic configuration of the entire rack and pinion type steering device for manual steering.

FIG. 6 shows an example of a conventional steering link device, (a) is an enlarged cross-sectional view of a main part showing a ball joint portion, and (b) is a VIb-VIb line sectional view thereof.

FIG. 7 is a schematic exploded perspective view for explaining an assembled state of a conventional lock washer and a rack end.

[Explanation of symbols]

 1 Rack and pinion type steering device 3 Steering body 4 Steering link device 5 Rack 7 Tie rod 10 Ball joint part 11 Ball 12 Ball joint main body 13 Screw part 14 Lock washer 14a Shaft hole 14d Bending piece 14e Bending piece 20a For arc-shaped detent Projection 20b Arc-shaped rotation-stop projection 21 21 Semi-circular concave groove

Claims (1)

[Scope of utility model registration request] 1. A steering link device in which a rack slidably held by a steering body and a tie rod connected to a steered wheel side are connected via a ball joint, wherein the rack and a screw connection thereto. It is interposed between the ball joint main body on the tie rod side and a part of it is locked to the end of the connecting side of the rack in a non-rotating state, and a part of the outer peripheral edge is bent and formed on the ball joint main body side. A lock washer for connecting the rack and the ball joint main body in the rotational direction by being locked with the lock washer. Is formed so as to have an arc shape that draws a substantially semi-circular locus, and the anti-rotation protrusion is provided at the end of the rack on the connection side. Substantially steering linkage, characterized in that the formation of the groove portion of the cross section substantially semicircular shape having a curvature equal.