JPH072354Y2 - Pinion housing waterproof structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a waterproof structure for a pinion housing of a steering gear box.

[Conventional technology]

A conventional steering mechanism for an automobile is shown in FIG. As shown in the figure, the steering torque that can be generated by rotating the steering wheel 1 is transmitted to the steering shaft 2, and further to the torque rod 4 provided via the universal joint 3, and further transmitted to the steering gear box 5. To be The steering gear box 5 is, for example, a rack and pinion type gear box, and the steering torque of the torque rod 4 is transmitted to a pinion shaft provided coaxially with the pinion gear. The steering torque of the pinion gear becomes a force for reciprocating the rack gear meshing with the pinion gear, and the force for reciprocating the rack gear steers the left and right tires via the tie rods 6.

An enlarged view of the steering gear box shown in FIG. 3 is shown in FIG. The figure shows a portion of the pinion housing of the steering gear box. In this conventional example, a torque rod 4 for transmitting a steering torque is fixedly connected to a peripheral portion of a rubber coupling 10 which is an elastic plate by a nut 13 and a bolt 11 at both ends of a flange 12a fixed to a lower end thereof. There is.

Further, on the lower surface of the peripheral portion of the rubber coupling 10, an arm-shaped flange 12b arranged in a direction orthogonal to the flange 12a is fixed by a nut 13 screwed to the tip.

This flange 12b is welded 15 to the end of the pinion shaft 14. The pinion gear 16 provided coaxially with the pinion shaft 14 is a pinion housing having a cylindrical opening 17.
Inserted in 18. The pinion shaft 14 is supported by a support bearing 19.

The support bearing 19 is formed by a snap ring 20 inserted next to the support bearing 19 in the pinion housing 18
It is fixed to the inner surface of. When the steering torque is transmitted to the torque rod 4 by such a structure, the pinion shaft 14 arranged at a constant angle with the torque rod 4.
Steering torque is transmitted to the rubber via rubber coupling 10 which is an elastic plate. This steering torque is further transmitted to the rack gear 21 meshing with the pinion gear 16 via the pinion gear 16.

The above-described waterproof structure of the pinion housing 18 is performed by the dust seal 22 inserted next to the snap ring 20.

The above-described assembly of the pinion housing is performed, for example, as follows. That is, with respect to the pinion shaft 14 provided with the pinion gear 16 coaxially, the support bearing 19,
After passing through the snap ring 20 and the dust seal 22, the flange 12b is welded to the end of the pinion shaft 14. Then, the pinion shaft 16 is inserted into the pinion housing 18 together with the pinion gear 16, and then the support bearing 19 is inserted into the pinion housing 18 to support the pinion shaft 14 and the like.

Next, the snap ring 20 is inserted into the pinion housing 18 by using the pliers 23 dedicated to the snap ring to fix the support bearing 19. Then, the dust seal 22 is inserted.

At this time, the minimum space S between the welded portion 15 and the opening 17 of the pinion housing 18 is set so that the snap ring 20 can be attached and detached by using the pliers 23 dedicated to the snap ring.
Is set. This space S is minimized to make the entire device compact.

However, improving the life of the lip 24 of the dust seal 22,
In order to reduce the tightening margin of the lip 24 and to simplify the shape of the lip 24, it is necessary to minimize the amount of muddy water that reaches the dust seal 22.

For this reason, it is necessary to provide a rubber dust protector 31 as shown in FIG. 5 to cover the opening 17. Since the primary waterproofing for preventing muddy water reaching the dust seal 22 can be performed in this way, the life of the lip 24 can be improved, the rotational friction of the dust seal 22 can be reduced, and the space for mounting the dust seal 22 can be reduced.

A second conventional example shown in FIG. 5 will be described. The same parts as those in FIG. 4 are designated by the same reference numerals and the description thereof will be omitted.

A serration 32 is formed at the end of the pinion shaft 14, and a rubber dust projector 31 is provided to the serration 32. For this reason, serrations on the pinion shaft 14
32, and mounting flange 33 and bolt 34 on flange 12b.
Must be provided. The reason why the welding 15 cannot be performed in this way is that if the welding 15 is performed, the above-mentioned minimum space S cannot be increased so much that the dust protector 31
This is because it is difficult to attach and detach the snap ring 20 using the pliers 23 dedicated to the snap ring in FIG.

The assembling process in the second conventional example can be performed as follows, for example. That is, the pinion shaft 14 provided with the pinion gear 16 coaxially is inserted into the pinion housing 18, and then the support bearing 19 is inserted to support the pinion shaft 14. Next, the snap ring 20 is inserted using the pliers 23 to fix the support bearing 19. After that, the dust seal 22 is inserted. Next, the rubber dust protector 31 is passed through the pinion shaft 14 to cover the opening 17 of the pinion housing 18.

Then, the flange 12b is fitted with serrations 3 as described above.
The mounting flange 33 is fitted to 2 and fixed by using bolts 34.

As a rack-and-pinion type staying mechanism of this type, there is, for example, Japanese Utility Model Laid-Open No. 57-53968, in which the strength of the pinion shaft is increased and the number of parts is greatly reduced.

[Problems to be solved by the device]

As described above, the first conventional example (FIG. 4) has a drawback that the dust protector cannot be provided, and the second conventional example (FIG. 5) has the serration 32 for providing the dust protector. Formed mounting flange 33 and bolt 34
Must be equipped with a flange 12 for the pinion shaft 14
There was a drawback that b could not be fixed by simple welding.

The present invention has been made to solve the above drawbacks,
(EN) Even in a pinion housing having a structure in which a flange 12b is fixed to a pinion shaft 14 by welding, an object is to obtain a waterproof structure of a pinion housing in which the dust protector 31 can be provided as a waterproofing means.

[Means for Solving the Problems]

In order to achieve the above object, a waterproof structure for a pinion housing according to the present invention is configured such that a torque rod for transmitting a steering torque and a pinion shaft are diverted from each other and are connected to a rubber coupling, which is an elastic plate, via a flange, The pinion gear provided coaxially with is inserted into a pinion housing having a substantially cylindrical opening, the pinion shaft is supported by a support bearing, and this support bearing is fixed to the pinion housing by a snap ring inserted next to the support bearing. In the waterproof structure of the pinion housing in which a dust seal is inserted next to the snap ring for waterproofing, a dust protector covering the opening portion of the pinion housing from the flange is provided, and the dust protector is elastic. With a bottomed cylindrical shape A plurality of windows that penetrate the arm-shaped flange are formed at the bottom, slits are provided at the edges of the windows to facilitate the penetration, and slits are provided at the ends of the cylindrical parts so that the ends of the cylindrical parts can be easily turned over. Is.

[Action]

According to the present invention configured as described above, even if the minimum space for attaching and detaching the snap ring using the pliers dedicated to the snap ring is provided between the welding portion and the opening, Regardless of existence
This desorption work can be performed.

That is, the flange is welded to the end of the pinion shaft while passing through the support bearing, the snap ring and the dust seal with respect to the pinion shaft provided with the pinion gear coaxially. After that, the dust protector is attached to the flange of the dust protector by inserting an arm-shaped flange from the inside into the window of the dust protector.

After that, the pinion gear, the pinion shaft, and the support bearing are inserted into the pinion housing. Then, the pliers for exclusive use of the snap ring are used to insert the snap ring to fix the support bearing. At this time, the cylindrical end of the dust protector is easily flipped by the slit, and the work of inserting the snap ring is not hindered. After this work is completed, the end of the cylindrical portion of the dust protector returns to its original position by elasticity and covers the opening of the pinion housing.

Therefore, even when the flange is welded to the end of the pinion shaft and the dust protector is provided, the work of inserting the snap ring and fixing the support bearing can be easily performed.

〔Example〕

An embodiment of the present invention will be described with reference to FIGS. The same members as those in FIG. 4 showing the conventional example are designated by the same reference numerals.

A torque rod 4 for transmitting a steering torque generated by rotation of a steering wheel (not shown) has a flange 12 having both ends fixed by a nut 13 and a bolt 11 at a peripheral portion of a rubber coupling 10 having a substantially disk shape which is an elastic plate.
connected through a. On the lower surface of the periphery of the rubber coupling 10, both ends of the arm-shaped flange 12b are bolts 1
Fixed by 1. The central portion of the flange 12b is welded to the end of the pinion shaft 14.

Both ends of this flange 12b are on the same plane, and this plane is orthogonal to the pinion shaft 14.

A pinion gear 16 provided coaxially with the pinion shaft 14 is inserted into a substantially cylindrical opening 17 of a pinion housing 18. Inside the pinion housing 18, the pinion shaft 14 is rotatably supported by a support bearing 19 so as not to move in the axial direction.

The support bearing 19 is fixed to the inner surface of the pinion housing 18 by a steering wheel 20 inserted next to the support bearing 19. The dust seal 22 is inserted next to the steering wheel 20, and the pinion housing 18
It is designed to prevent rainwater and muddy water from entering inside. The lip portion 24 of the dust seal 22 slides in contact with the outer surface of the pinion shaft 14.

A dust protector 41 is provided on the flange 12b,
The dust protector 41 covers a portion from the flange 12b to the opening 17 of the pinion housing 18.

The dust protector 41 has elasticity, has a substantially cylindrical shape with a bottom, as shown in FIG. 2, and is provided with its bottom portion facing upward. Two windows 42 are formed in the bottom portion for penetrating the arm-shaped flange 12b. This window 42
A slit 43 is provided on the top and bottom at the center of the edge. The slit 43 facilitates the penetration. Further, at the end of the cylindrical portion of the dust protector 41, a slit 44 is provided along the generatrix of the cylindrical portion so that the end of the cylindrical portion can be easily turned up. Snap ring for easy flipping
The attachment / detachment work of 20 becomes easy, and even after the dust protector 41 is attached, even if the posture of the dust protector 41 is slightly misaligned and the end of the cylindrical portion comes into contact with the opening 17 of the pinion housing 18, noise and rotation resistance do not occur.

A long slit 45 is formed in the center of the two windows 42,
When the flange 12b is passed through the 42, the entire dust protector 41 is largely deformed to facilitate the penetration.

Next, the assembly process in this embodiment will be described. An arm-shaped flange 12b is welded to the end of the pinion shaft 14 in the same manner as in the conventional example. After this welding, the dust protector 41
Cover each flange 12b. At this time, the dust protector 4
The slits 43 and 45 provided in 1 facilitate the penetration. At that time, the opening 17 of the pinion housing 18
Then, the pinion gear 16 and the pinion shaft 14 are inserted, and then the support bearing 19 is inserted to fix the pinion shaft 14.

Then, the snap ring 20 is inserted by the pliers 23 to fix the support bearing 19. When the snap ring 20 is inserted, the dust protector 41 is easily turned over by the function of the slit 44 (shown by the diagonal lines in FIG. 1).

Also, this assembly process can be performed in another order. That is, the dust protector 41 is not assembled immediately after welding, but after the welding, the pinion gear 16, the pinion shaft 14, the support bearing 19, the snap ring 20, and the dust seal 22.
It is also possible to assemble the dust protector 41 after the insertion of all of the. In this case, the snap ring
When the 20 is inserted, the dust protector 41 is not yet attached, so that the snap ring can be inserted more easily.

In addition, as the pinion shaft 14 rotates, the dust protector shaft
The dust protector 41 also rotates with the rotation of 14, but at this time, even if the posture of the dust protector 41 is slightly misaligned and the end of the cylindrical portion comes into contact with the opening 17, noise and rotation resistance are generated. There is no.

The presence of the dust protector 41 makes it difficult for rainwater and muddy water to reach the dust seal 22 and to produce the primary waterproofing effect. Then, since the rainwater and the muddy water that have passed through the slits of the dust protector 41 are discharged from the end of the cylindrical portion of the dust protector 41, that is, the gap between the opening 17, the muddy water is accumulated inside due to the presence of the dust protector 41. There is no worry that it will end.

Further, since the primary waterproofing effect is produced, unlike the first conventional example (FIG. 4), since there is no dust protector, the grease applied to the lip 24 of the dust seal 22 adheres to the mud and disappears. It is possible to prevent the lip 24 part from being worn. Also, due to the dust lip phenomenon caused by the mud accumulated between the dust seal 22 and the pinion shaft 14, the surface of the surface-treated pinion shaft 14 is worn away and rust is generated, and the lip 24 of the dust seal 22 is also worn away. That can be prevented. Therefore, the life of the dust seal 22 can be extended.

The first waterproofing effect is that the amount of water accumulated in the dust seal 22 can be reduced, and the icing between the dust seal 22 and the pinion shaft 14 can be reduced to a negligible amount. Therefore, the lip of the dust seal 22 caused by the icing can be reduced. The shape of the lip 24 of the dust seal 22 and the dust seal are eliminated by eliminating the tearing of the 24 and the idling without contacting the pinion shaft 14.
The degree of freedom in design can be expanded in the press-fitting width when the pinion shaft 14 is press-fitted into the pin 22, and also in the mounting space of the dust seal 22 and the like.

[Effect of device]

Since the present invention is configured as described above, the dust protector has elasticity, and a window is formed to allow an arm-shaped flange to penetrate therethrough. Can be covered. Therefore, the dust protector can be attached after the work of inserting the snap ring into the pinion housing. Alternatively, even when the dust protector is attached, the slit at the end of the cylindrical portion of the dust protector makes it easy to insert the flip-up snap ring at the end of the cylindrical portion.

Therefore, the dust protector can be provided even in the pinion housing in which the flange is welded to the end of the pinion shaft, and the snap ring insertion operation can be easily performed.

[Brief description of drawings]

FIG. 1 is a partially cutaway view showing a waterproof structure of a pinion housing showing a first embodiment of the present invention, FIG. 2 is a perspective view showing the dust protector of FIG. 1, and FIG. 3 is a conventional steering mechanism. FIG. 4 is a sectional view of the pinion housing of the first conventional example used in FIG. 3, and FIG. 5 is a partially cutaway view of the pinion housing of the second conventional example. 4 ... Torque rod, 10 ... Rubber coupling, 12a,
12b ... Flange, 14 ... pinion shaft, 16 ... pinion gear, 17 ... opening, 18 ... pinion housing, 19 ...
… Supporting bearing, 20 …… Snap ring, 22 …… Dust seal, 31,41 …… Dust protector, 42 …… Window, 43,
44,45 …… Slit.

Claims (1)

[Scope of utility model registration request] 1. A pinion gear provided coaxially with a pinion shaft, wherein a torque rod for transmitting a steering torque and a pinion shaft are deflected from each other and connected to a rubber coupling, which is an elastic plate, via an arm-shaped flange. The pinion shaft is supported by a support bearing, which is fixed to the pinion housing by a snap ring inserted next to the support bearing, and the dust seal is installed next to the snap ring. In the waterproof structure of the pinion housing that is inserted and waterproofed, a dust protector covering the opening portion of the pinion housing from the arm-shaped flange is provided, and this dust protector has a substantially bottomed cylindrical shape with elasticity. The compound bottom that has an arm-shaped flange that penetrates the bottom Windows to form a waterproof structure of the pinion housing, wherein said slit to facilitate penetration provided, the cylindrical portion end provided with easily turned up as the slit in the cylindrical portion end on the edge of the window.