JPH0125746Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a coupling structure between a valve sleeve and a pinion shaft of a rotary valve of a power steering device used in a vehicle.

Conventionally, a valve sleeve and a pinion shaft of a power steering device used in a vehicle are generally connected by a pin. This will be explained with reference to FIG.

FIG. 1 is a sectional view of a rotary valve portion of a power steering device for a vehicle. In FIG. 1, a valve shaft 14 is inserted from the center of one axial end of a valve housing 12 to which a nozzle 10 coupled to an oil pipe is attached. The valve shaft 14 has a cylindrical shape and has a torsion bar 16 inserted therein, one end of the torsion bar and a pin 1.
They are joined by 8. In addition, the valve shaft 14 has a surface 2 parallel to its tip as shown in FIG.
An engaging convex portion 24 having a diameter of 0,22 is formed, and a plurality of port portions 26 are formed on the outer peripheral surface of the portion inserted into the valve housing 12. The other end, that is, the tip end of the torsion bar 16 is fitted into the pinion shaft 28 and connected to the pinion shaft by a pin 30. This pinion shaft 28 has two stopper parts 32 and 34 at its rear end, that is, the end on the side connected to the torsion bar 16, as shown in FIG.
It is said to have a half-split structure. These stopper parts 32 and 34 are formed by notches 36 and 38 having a predetermined opening angle from the center of the pinion shaft 28 toward the outer circumference, and the stopper parts 32 and 34
A, 32B, 34A, and 34B, and a hole into which a coupling pin 40 is inserted is formed in the stopper portion 32.

Note that the engagement convex portion 24 of the valve shaft 14 is
As shown in Figures 1 and 4, the pinion shaft 2
It is inserted between the stopper parts 32 and 34 of the pinion shaft 28 so that the surfaces 20 and 22 of the engagement convex part come into contact with the stopper parts 32 and 34 of the pinion shaft 28 when the valve shaft 14 rotates by a predetermined angle. There is.
Furthermore, the stopper parts 32 and 34 are fitted into the tip of a valve sleeve 44 provided around the valve shaft 14 within the valve housing 12, and are connected to the valve sleeve 44 by a coupling pin 40 into which the stopper part 32 is press-fitted. are combined. The pinion shaft 28 also has a stopper portion 32,
A bearing 46 is fitted onto the outer circumferential surface of the valve housing 34 so as to be rotatable relative to the valve housing 12.

Therefore, when the driver turns the steering wheel (not shown) to the right and the valve shaft 14 rotates clockwise by a predetermined angle or more in FIG. The pinion shaft 28 is rotated clockwise while contacting the stopper surfaces 32A, 34B of the stopper parts 32, 34. and,
Since the valve sleeve 44 is coupled to the pinion shaft 28 by the coupling pin 40, the valve sleeve 44 rotates clockwise integrally with the pinion shaft 28 as the pinion shaft 28 rotates clockwise. The same applies to the case where the valve shaft 14 rotates counterclockwise.

However, the above structure has various drawbacks because the pinion shaft 28 and the valve sleeve 44 are connected by a pin. That is, the valve shaft 14 and the valve sleeve 44
This means that the valve must be kept in the neutral position. However, since the valve sleeve is connected to the pinion shaft 28 by a pin, the pinion shaft 2
Due to the misalignment of the pin holes 8, it is difficult for the valve shaft 14 and the valve sleeve 24 to take a relative neutral position. Conversely, when the valve shaft 14 is to take the valve neutral position with respect to the valve sleeve 44, the pinion shaft 28
This makes it difficult to obtain accurate pin holes for the coupling pins 28 drilled in the stopper portions 32. Also,
When disassembling and repairing power steering equipment, etc.
When removing the bearing 46, remove the valve sleeve 4.
4 from the pinion shaft 28, and at this time it is necessary to pull out the coupling pin 40. That is, after removing the valve housing 12, the coupling pin 40 is pulled out, or the coupling between the torsion bar 16 and the pinion shaft 28 is released by pulling out the pin 30, and the valve shaft 14 is pulled out from the end of the pinion shaft, and then the coupling pin is removed. 40 between the stops 32, 34 of the pinion shaft 28 to disengage the valve sleeve from the pinion shaft 28. When the coupling pin 40 is to be pulled out, it is not easy because the coupling pin 40 is press-fitted, and the coupling pin will be damaged, making it impossible to reuse the coupling pin 40. On the other hand, if the coupling pin 40 is to be pulled out without removing the valve shaft 14, the number of man-hours required to remove the valve shaft 14 is required, and prompt service cannot be achieved. Further, the coupling pin 40 is connected to the pinion shaft 2
8, the cross-sectional area of the stopper part 32 is reduced, and the strength of the stopper part 32 is reduced due to internal stress caused by the press-fitted connecting pin.

The present invention has been made in order to eliminate the drawbacks of the prior art, and an object of the present invention is to provide a power steering device that can be easily disassembled and repaired.

In the present invention, a ring groove is formed on the inner circumferential surface of one end of the valve sleeve, and a convex portion formed on the inner circumferential surface of a snap ring that is fitted into the ring groove is brought into contact with a stopper portion of the pinion shaft, so that the pinion shaft receives the ring groove. The rotational force is transmitted to the valve sleeve via the snap spring so that the pinion shaft and the valve sleeve rotate integrally, and the axial movement of the valve sleeve is caused to fit externally onto the valve shaft. It is configured to be regulated by a retaining ring.

A preferred embodiment of the power steering device according to the present invention will be described with reference to the accompanying drawings. Note that the same reference numerals are given to the parts corresponding to the parts explained in the prior art, and the explanation thereof will be omitted.

FIG. 5 is a cross-sectional view of the engagement portion between the pinion shaft and the valve sleeve in the embodiment of the power steering device according to the present invention, and FIG. 6 is a perspective view of the embodiment of the snap spring used in FIG. 5. , FIG. 7 is a sectional view taken along the - line in FIG. 5. In FIG. 5, the valve sleeve 44
A notch 48 is formed at one end, that is, the end on the pinion shaft 28 side, and a ring groove 50 is formed on the inner peripheral surface of the end. A snap ring 54 having a claw piece 52 inserted into a notch 54 is fitted into the ring groove 50. As shown in FIG.
A claw piece 52 to be inserted is formed, and a convex portion 56 is formed on the outer peripheral surface corresponding to this claw piece 52.
Furthermore, the snap spring 54 has a cut formed in a portion opposite to the convex portion 56, and has an operation hole 5 at each end.
8 is drilled. As shown in FIG.
2A and 34A, respectively, and the rotational force of the snap spring 28 is transmitted to the snap spring 54, and further transmitted to the valve sleeve 44 via the claw piece 52 of the snap spring 54. Therefore, the valve sleeve 44 rotates integrally with the pinion shaft 28 as the pinion shaft 28 rotates.

Note that the snap spring 54 is inserted into the ring groove 50 of the valve sleeve 44 through the operation holes 58, 58.
Insert a jig into the snap spring 5 and apply force in the direction to shorten the gap between the cuts in the snap spring 54.
This can be done by reducing the diameter of the snap ring 4, inserting the claw piece 52 into the notch 48, and then releasing the force applied to the snap spring 54 via a jig. Then, the valve sleeve 44 into which the snap spring 54 has been fitted is fitted onto the valve shaft 14 as shown in FIG.
2 and 34 and engage them. after that,
The retaining ring 60 is fitted into a groove formed in the valve shaft 14 near the rear end (upper part in FIG. 7) of the valve sleeve 44. Therefore, the valve sleeve 44 can only move in the axial direction when the pinion shaft 2
It is regulated by the ends of the stopper parts 32 and 34 of No. 8 and a retaining ring 60.

In the above configuration, when it is necessary to remove the bearing 46 for disassembling or repairing the power steering device, the valve sleeve 44 can be easily removed by removing the retaining ring 60 after removing the valve housing 12. It can be taken out. Therefore, not only is it extremely easy to remove the bearing 46, but there is no wear and tear on parts during disassembly and repair, improving service and reducing costs. Furthermore, since it is not necessary to form a pin hole etc. in the pinion shaft 28, the pinion shaft 28
It is possible to improve the strength of 8.

FIG. 8 is a front view showing another embodiment of the snap spring 54. When the valve sleeve 44 is placed in the valve neutral position, if the notch 48 is deviated from the center position between the stopper portions 32 and 34 of the pinion shaft 28, as shown in FIG.
By providing the claw piece 52 of the snap spring 54 offset from the center of the convex portion 56, the neutral position of the valve can be properly maintained. Note that it is desirable that the claw piece 52 and the convex portion 56 be in corresponding positions;
It does not have to be in the corresponding position.

As explained above, according to the present invention, the pinion shaft and the valve sleeve are engaged with each other via the snap spring fitted into the valve sleeve, and the movement of the valve sleeve in the axial direction is transferred to the end of the pinion shaft and the valve shaft. Disassembly and repair of the power steering device is facilitated by restricting it with the fitted retaining ring.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the rotary valve part of a conventional power steering device, Fig. 2 is a perspective view of the tip of the valve shaft, Fig. 3 is a perspective view of the rear end of a conventional pinion shaft, and Fig. 4 is a conventional FIG. 5 is a plan sectional view of the connecting portion between the pinion shaft and the valve sleeve of the power steering device according to the embodiment of the present invention; FIG. Fig. 6 is a perspective view of one embodiment of the snap spring according to the present invention, Fig. 7 is a sectional view of the rotary valve part of the embodiment of the power steering device according to the present invention, and Fig. 8 is a front view of another embodiment of the snap spring. It is a diagram. 14... Valve shaft, 16... Torsion bar, 24... Engaging convex portion, 28... Pinion shaft, 32, 34... Stopper portion, 44... Valve sleeve, 48... Notch, 50... Ring groove , 52...Claw piece, 54...Snat spring, 6
0...Stop ring.

Claims (1)

[Scope of utility model registration request] a valve shaft having an engagement protrusion formed in the center of one end; a torsion bar inserted into the center of the valve shaft along the axis and having one end coupled to the valve shaft; and the engagement protrusion of the valve shaft. As the valve shaft is rotated through a predetermined angle, a stopper portion is formed that comes into contact with the engaging convex portion, and the pinion shaft connected to the other end of the torsion bar and the periphery of the valve shaft are formed. A power steering device including a valve sleeve provided at the one end of the valve sleeve and having one end fitted onto the pinion shaft so as to rotate integrally with the pinion shaft, a notch formed in the one end of the valve sleeve; A ring groove is formed on the inner circumferential surface of the one end of the sleeve, a protruding claw piece is provided on the outer circumferential surface to be inserted into a notch formed in the valve sleeve, and a convex portion is provided on the inner circumferential surface for abutting against the stopper portion of the pinion shaft. a set ring that is formed and fitted into a ring groove of the valve sleeve that has a cut at a position opposite to the convex portion; and a stop ring that is fitted onto the valve shaft and restricts axial movement of the valve sleeve. A power steering device characterized by: