JPS621013Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dust boot attachment device, and more particularly to an improvement in a dust boot attachment device installed in a steering gear housing (rack insertion pipe) of a rack and pinion type steering device.

For example, between the steering gear housing of a rack and pinion type steering device and a rack shaft that is fitted in the steering gear housing so as to be slidable in the axial direction, one end of the rack shaft is attached to the outer periphery of one end of the steering gear housing. A dust boot made of a bellows is fitted onto a rack shaft whose other end protrudes from one end of the steering gear housing, and the dust boot protects the sliding parts between the steering gear housing and the rack shaft, etc. They are usually airtightly sealed to prevent water, dust, etc. from entering.

Conventionally, the above-mentioned bellows end is attached to the steering gear housing by tightening and fixing the outer circumference of the bellows end, which is inserted into the outer circumferential surface of the steering gear housing, using a belt-shaped clamp. However, the above-mentioned belt-shaped clamp is omitted, and a bracket for attaching the steering gear housing to a fixed member such as a chassis member is used, and the above-mentioned bracket is placed around the outer periphery of the end of the boot that is inserted into the outer periphery of the steering gear housing, and both sides of the bracket are attached. By tightening and fixing the end to a fixed member such as a chassis frame with bolts, etc., the end of the boot can be tightened to the steering gear housing and the steering gear housing can be attached to the fixed member at the same time using a bracket. It was previously developed and published in Japanese Utility Model Application Publication No. 16915/1983.

However, in such conventional devices, the attachment part of the steering gear housing to a fixed member such as a chassis frame must be formed into a flat surface to improve stability in the attached state, so the bellows end that is fitted into it must be However, part of the entire circumference must be made flat, which not only makes it difficult to form when forming the dust boot and increases costs, but also the part that is compressed and deformed by being directly tightened with the bracket at the end of the bellows. There is a problem in that ozone cracks often occur near the boundary between the boot and the part that is not tightened, and the boot may be damaged from that part.

The main purpose of the present invention is to solve the problems of the conventional device as described above, and embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIGS. 1 and 2, 1 is a rack shaft, 2 is a pipe-shaped steering gear housing (hereinafter simply referred to as a pipe) that fits and supports the rack shaft 1 so as to be slidable in the axial direction, and 6 is a pipe-shaped steering gear housing. It's easy. Reference numeral 3 denotes a bellows, and a cylindrical attachment part 7 for fitting onto the outer peripheral surface of the pipe 2 is formed at one end of the bellows 3, and a flange projecting outward is formed at the tip of the attachment part 7. A portion 8 is formed over the entire circumference. Although not shown in the drawings, the other end of the bellows 3 is formed with a small-diameter mounting portion that is fitted onto the outer peripheral surface of the rack shaft 1 or a link rod, etc., which is connected to the tip of the rack shaft via a joint. A dust boot is constituted by the bellows 3, the attachment portions 7 at both ends thereof, the small diameter attachment portions, and the like.

Reference numeral 4 denotes an insulator made of an elastic material such as rubber, and as shown in FIG. A recessed portion 1 into which a bracket 5 to be described later is fitted is provided on the outer peripheral surface other than the portion.
3, and has a recess 9 provided all around the inner periphery of one end of the center hole 11 into which the mounting portion 7 and flange 8 of the end of the bellows 3 are fitted. The approximately central portion of the flat portion 12 is divided into left and right parts by a notch or slit 14, and the insulator 4 is widened left and right by this notch or slit 14, and the bellows end can be attached as described later. It can be fitted into the outer peripheral surface of the portion 7 and the pipe 2.

In the above, the fitting portion 7 at the bellows end is fitted onto the outer circumferential surface of the pipe 2, and the insulator 4 made of an elastic material such as rubber is deformed to widen left and right from the notch or slit 14 as described above. The mounting portion 7 is fitted onto the outer periphery of the mounting portion 7, and the mounting portion 7 and the flange portion 8 at its tip are fitted into and engaged with the recess 9 provided on the inner peripheral surface of the center hole of the insulator 4, as shown in FIG.

Then, as shown in FIG. 2, the flat part 12 on the outer periphery of the insulator 4 is stacked on a fixed member such as the chassis frame 10, and the recessed part 1
3, and the both ends of the bracket 5 are tightened and fixed to a fixed member such as the chassis frame 10 with bolts or the like, and the pipe 2 is attached to the fixed member.

In this state, the entire outer circumference of the pipe 2 is held tightly by the inner circumferential surface of the center hole of the insulator 4 which is tightened by fixed members such as the bracket 5 and the chassis frame 10, and the pipe 2 is held by the bellows by the insulator 4. The inner circumferential surface of the end attachment portion 7 is tightly pressed against the outer circumferential surface of the pipe 2, and the collar portion 8 is firmly engaged and held within the recess 9.

As described above, the present invention eliminates the need for a dedicated clamp for attaching the dust boot, thereby simplifying the attachment work.

In addition, in the present invention, the bellows end of the dust boot is clamped and pressure-welded to the outer circumferential surface of the pipe 2 via the insulator 4 with its cylindrical attachment portion 7 and collar portion 8 fitted into and engaged with the recess 9 of the insulator 4. Therefore, the dust boot can be tightly and reliably fixed without providing any protrusions or recesses on the outer peripheral surface of the pipe 2 to prevent the dust boot from coming off, and the sealing performance can be improved.
Since the dust boot is not directly tightened with a metal bracket, ozone cracks around the mounting part and the resulting damage to the dust boot are almost completely prevented, and the elasticity of plastic etc. Reliable sealing performance can be maintained for a long period of time even when using fragile materials.

Furthermore, in the present invention, the pipe 2 is the insulator 4.
Since it is structured so that it can be attached to a fixed member such as a chassis frame through the pipe 2, there is no need to provide a flat part on the pipe 2 to ensure installation stability, and a pipe material with a simple circular cross section can be used. , the attachment part of the bellows end fitted thereto can also be made into a cylindrical shape with a simple circular cross section, the structure of the pipe 2 and the dust boot is simple, the moldability is good, and costs can be reduced.
This can bring about great practical effects.

The present invention can be applied not only to a dust boot that seals between a steering gear housing and a rack shaft, but also to a dust boot that is installed between any two members that are combined so that they can move relative to each other in the axial direction. Needless to say.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing an embodiment of the dust boot attachment part of the present invention, and Figure 2 is A in Figure 1.
-A sectional view. 3A and 3B are a front view and a BB sectional view of the insulator shown in FIGS. 1 and 2. FIG. DESCRIPTION OF SYMBOLS 1... Rack shaft, 2... Steering gear housing, 3... Bellows, 4... Insulator, 5... Bracket, 7... Mounting part, 8... Flam part, 9... Recessed part, 10... Chassis flame.

Claims (1)

[Claims for Utility Model Registration] (1) In the dust boot mounting device, an outwardly protruding flange is provided at the end of the bellows end where it is attached to the mating part, and the flange is fitted onto the outer peripheral surface of the mating part. The insulator is provided with a recess on the inner periphery of the central hole to fit and engage the end of the mounting part and the flange over the entire circumference of the insulator. 1. A dust boot mounting device, characterized in that the insulator is fitted into the insulator, the outer circumference of the insulator is bent with a bracket, and the insulator is fastened to a fixing member. (2) The dust boot attachment device according to claim 1, wherein the insulator has a flat portion formed on a part of its outer periphery to be joined to the fixing member.