JPS633882Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a boot mounting structure for a rack-and-pinion steering gear, and more particularly to a boot mounting structure for a rack-and-pinion steering gear equipped with a steering damper.

The conventional mounting structure of the rack boot for protecting the rack bar of this kind of rack-and-pinion steering gear (hereinafter simply referred to as "steering gear") is to install a cylindrical steering damper (hereinafter simply referred to as "damper") in parallel with the steering gear. In order to install a damper support part on the rack bar side, the damper support part was enclosed in the rack boot, and the damper mounting member of the damper support part was provided in a part of the boot. There was a method in which the damper supporting portion was exposed through the hole and fastened to the damper, and a method in which the damper support portion was exposed by providing a separate boot for the ball joint. The former complicates the structure of the boot, which may reduce its durability, while the latter requires the end of the boot on the housing side to be placed inside the stopper surface on the housing side in order to ensure the minimum shrinkage margin of the boot. The span for supporting the steering gear on the vehicle body was regulated by the position of the end of the boot.

FIG. 1 is a cross-sectional view showing essential parts in a specific example of a conventional method of exposing a damper support portion. In the figure, a substantially disc-shaped boot mounting fitting 4 is attached to the end surface of the rack bar 2 by a ball joint 6. A bottom portion of a holder 8 having an L-shaped cross section and a substantially dish-like outer shape is concentrically fixed to the boot mounting bracket 4 by spot welding or the like. One end of this holder 8 is bent outward on the circumference to form a protrusion 8.
0, and the protrusion 80 of the boot holder 8
A groove 10 is formed between the boot mounting bracket 4 and the boot mounting bracket 4.

Further, the bellows-shaped rack boot 12 is formed in a cylindrical shape, and has a thick fitting portion 12 at its end.
0, and a groove 121 is provided on the outer edge of this fitting portion 120.

The steering wheel and the rack boot 12 configured as described above are fixed by fitting the fitting part 120 of the rack boot 12 into the groove part 10, and fitting the band 14 into the groove 121 of the fitting part 120 and tightening it. It is something. Note that the symbol _L10 indicates the required dimensions for attaching the rack boot.

In this method of tightening the easy boot 12 with the band 14, the length _L10 is not included in the shrinkage margin of the boot, so in order to secure the shrinkage margin of the boot, the end of the boot on the housing side is further extended. The span provided on the housing side to support the steering gear on the body is shortened, and as a result, there is a drawback that sufficient rigidity cannot be obtained. In addition, in the above-mentioned tightening method, the tightening force of the band 14 is only applied in the circumferential direction of the rack boot 12, and there is no seal against air, water, etc. that enters from the gap between the joint surface of the boot mounting bracket 4 and the holder 8. could not be expected, and as a result, there was also the drawback that airtightness could not be maintained sufficiently. Furthermore, the above-mentioned tightening method also had the disadvantage of requiring a large number of parts.

The purpose of the present invention is to eliminate the drawbacks of the above-mentioned prior art, simplify the mounting structure, improve airtightness, and achieve high reliability. The object of the present invention is to provide a boot mounting structure.

The above object is to provide a rack boot comprising a damper support member, a disk-shaped boot mounting bracket held between a rack bar and a ball joint, and an annular end portion of the boot mounting bracket in contact with a side surface on the rack bar side; a holder which is an annular body having an L-shape in cross section and is fixed to the boot mounting bracket, grips the entire circumference of the annular end of the easy boot, and brings it into close contact with the boot mounting bracket, the holder of the easy boot; An annular protrusion is formed on a surface to be grasped by the holder, and a portion of the holder that grasps the boot has an annularly bent tip and a recess that fits into the annular protrusion of the easy boot. This is achieved by the rack-and-pinion steering gear boot mounting structure.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 2 is a plan view showing a schematic configuration of a rack-and-pinion type steering gear to which an embodiment of the present invention is applied. In this figure, the same components as in FIG. 1 are given the same reference numerals and will be explained. The steering gear 20 shown in the figure is a gear housing 2
A pinion 24 is provided for driving the rack bar to move it in the axial direction, and rack boots 32 and 33 are provided at both ends of the gear housing 22. One end of the rack boot 33 is fixed to the gear housing 22, and the other end is fixed to the tie rod 26 including a ball joint. The other rack boot 32 is fitted onto the rack bar, and has one end fixed to the gear housing 22.
The other end is fixed to the side surface of the boot mounting bracket 4 on the rack bar side. A steering damper support portion 28 is integrally formed on the boot mounting bracket 4 . This steering damper support part 2
8 is attached with a movable end 300 of a steering damper 30 installed with its axis parallel to the rack bar, and a fixed end 301 of this steering damper 30 is attached to a mounting seat 220 provided on the gear housing 22. There is. In addition, the code
L _B is a support span when attaching the steering gear 20 to the vehicle body. Further, reference numeral 6 is a ball joint, and a tie rod 26 is provided at one end of the ball joint.

FIG. 3 is a partial sectional view showing an embodiment of the steering gear boot mounting structure according to the present invention. Also in FIG. 3, the same components as in FIGS. 1 and 2 are given the same reference numerals and will be explained. Third
In the embodiment shown in the figure, a boot fitting 4 is attached to the end surface of the rack bar 2 by a ball joint 6. The boot attachment fitting 4 is formed into a substantially disk shape, and is adapted to fit closely into an opening 320 at an annular end of the rack boot 32 near its outer edge.

Opening 3 in the annular end of the rack boot 32
The holder 34 for gripping and fixing the rack boot 20 has a substantially L-shaped cross section and an annular outer shape, and a folded part 340 is provided on the inner diameter of the holder 34 for gripping the annular end of the rack boot. Further, the holder 34 is provided with a claw 341 that can be caulked when the annular end of the easy boot 32 is brought into close contact with the boot mounting bracket as shown in the figure.

The opening 320 of the rack boot 32 is tightly fitted by caulking the claw 341 of the holder 34 in the direction of the arrow in the figure in the axial direction of the rack 2 near the outer edge of the end face of the boot mounting bracket 4. , fixed, and easy boots 3
The end face openings 320 of 2 are provided with holders 3 alternately around the entire circumference.
4 is applied in the axial direction of the rack bar 2. As a result, there is no need to consider sealing between the retainer and the boot mounting bracket, unlike in the past.
The rack boot 32 is securely fixed to the boot mounting bracket 4 to ensure airtightness. In addition, L ₂₀ is the installation thickness (dimensions) of the easy boot 32.
This shows that.

Further, a folded portion 34 is provided on the inner diameter of the holder 34.
As mentioned above, 0 is set,
As a result, damage to the rack boot 32 caused by contact between the rack boot 32 and the holder 34 can be prevented. The step 342 on the end face of the sheet metal formed by the folded part 340 is
An annular protrusion 321 provided in the opening 320 of No. 2
Since the holder 34 is fitted with the holder 34, the tightening force of the holder 34 in the axial direction of the rack bar is sufficiently transmitted to the rack boot 32, resulting in a perfect seal and also having the advantage of preventing the rack boot 32 from falling off. Note that this embodiment has the advantage that assembly is easy and the number of assembly steps can be reduced.

FIG. 4 is a sectional view of a main part showing another embodiment of the rack boot mounting structure according to the present invention. The embodiment shown in FIG. 4 differs from the embodiment shown in FIG. 3 in that the holder 34 is screwed onto the outer peripheral edge of the boot mounting bracket 4 with a screw 36, and no other components have been changed. Since there is no , the same reference numerals are given and the explanation is omitted.

This embodiment has the advantage that the rack boot can be securely fixed.

According to the rack boot mounting structure configured as described above, the boot mounting dimension is L ₂₀ in this embodiment, compared to the conventional boot mounting dimension L ₁₀ (see Figure 1), which allows the mounting dimension to be shortened. Therefore, the total length of the easy boot is shortened, and the steering gear 20
The support span when attaching the steering gear to the vehicle body is expanded, and the rigidity of supporting the steering gear to the vehicle body is improved.
Furthermore, in this embodiment, the tightening force for attaching the rack boot is applied in the axial direction of the rack.
Airtightness can be significantly improved. In addition, according to this embodiment, in addition to being able to reduce the number of parts, it is also possible to reduce the number of assembly steps.

As described above, according to the present invention, the end of the ring-shaped rack boot is tightly attached to the side surface of the disk-shaped boot mounting bracket on the rack bar side by the holder, which is an annular body having an L-shaped cross section. An annular protrusion is provided on the surface of the end of the easy boot that is gripped by the holder, and a recess that fits with the annular projection of the easy boot is provided by bending the easy boot gripping part of the holder. So,
This has the effect of improving the reliability of the steering gear by improving the sealing performance between the rack boot and the boot mounting bracket, and shortens the length of the rack boot in the axial direction of the rack bar, which is necessary to tightly attach the rack boot to the boot mounting bracket. This has the effect of increasing the span for supporting the gear to the vehicle body, and providing sufficient support rigidity at the portion where the steering gear is fixed to the vehicle body.

[Brief explanation of the drawing]

Fig. 1 is a partial sectional view showing a conventional example, Fig. 2 is a plan view showing the overall schematic configuration of a rack-and-pinion type steering gear to which the present invention is applied, and Fig. 3 is a rack-and-pinion type steering wheel according to the present invention. FIG. 4 is a partial cross-sectional view showing one embodiment of a gear boot mounting structure, and FIG. 4 is a cross-sectional view of essential parts showing another embodiment. 2... Rack bar, 4... Boot mounting bracket, 6
... ball joint, 22 ... gear housing, 30 ... steering damper, 32 ... rack boot, 320 ... annular end opening, 32
1... Protrusion, 34... Holder, 340... Bent part, 342... Recess (step).

Claims (1)

[Claims for Utility Model Registration] A gear housing, a rack bar inserted through the gear housing and movable in the axial direction, a ball joint connected to an end of the rack bar, and a gear mounted parallel to the rack bar. a steering damper fixed to a housing and a damper support member at an end of the rack bar; a rack boot for protecting the rack bar fitted over the rack bar;
A rack boot mounting structure for a steering gear comprising: a disc-shaped boot mounting bracket made of a damper support member and held between the rack bar and the ball joint; a rack boot having an end portion; a holder that is an annular body having an L-shaped cross section and is fixed to the boot mounting bracket and grips the entire circumference of the annular end of the rack boot to bring it into close contact with the boot mounting bracket; an annular protrusion is formed on a surface of the rack boot that is gripped by the holder;
A rack-and-pinion steering gear characterized in that a portion of the holder that grips the rack boot has an annularly bent tip and a recess that fits into an annular protrusion of the rack boot. Boot mounting structure.