JPH0137900Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a press-fitting jig used for press-fitting an oil seal into a fitting hole formed at one end of a housing.

<Prior Art> For example, a cylinder device used in a rack-and-pinion type power steering device has a fitting hole formed on the inner periphery of one end of the housing on the side where the cylinder tube is fixed, and the inside of the cylinder tube is inserted into this fitting hole. An oil seal was press-fitted to seal the side of the rod that was inserted.

This oil seal is press-fitted into the fitting hole with a certain shimmy allowance during assembly, but if this press-fit is insufficient, oil may get stuck inside the cylinder tube due to adverse conditions such as oil adhering to the outer periphery of the oil seal. There is a problem in that the oil seal may come off due to the negative pressure inside the cylinder that is generated when air is removed from the cylinder tube to fill the oil.

<Problem to be solved by the invention> As a countermeasure to this problem, if an oil seal with a large outer diameter is used to increase the interference margin, the rubber on the outer peripheral side of the oil seal protrudes without being press-fitted as it is press-fitted. If this protruding rubber gets caught between the end surface of the housing and the stopper surface of the press-fit jig,
There was a problem in that the rubber was cut and the seal length on the outer circumferential side of the oil seal was shortened, impairing the sealing function.

<Means for Solving the Problems> The present invention has been made to solve the above-mentioned problems, and includes forming a pressing surface that comes into contact with the end surface of the oil seal at one end of the press-fitting jig, and A stopper surface is formed that contacts one end of the housing at a position radially outward from the surface, and an annular recess is formed between the pressing surface and the stopper surface to release the rubber protruding from the oil seal. .

<Example> Hereinafter, an example of the present invention will be described based on the drawings. In FIG. 2, 10 indicates a housing;
This housing 10 is supported by the frame of an automobile. A through hole 10a is formed in the housing 10, and a steering rod 11 is inserted into the through hole 10a.
is inserted. Both ends of the steering rod 11 are connected to tie rods 13 via ball joints 12. A rack 11a is formed on the outer periphery of one end of the steering rod 11.
a is engaged with a pinion shaft 14 rotatably supported by the housing 10. The pinion shaft 14 is connected to the handle shaft via a servo valve device (not shown). A piston 15 is integrally connected to the steering rod 11.
5 is slidably fitted into a cylinder tube 16 integrally connected to the housing 10.

A stepped hole 21 is formed inside the end of the cylinder tube 16, and a rod guide 22 that slidably supports the steering rod 11 is fitted into the stepped hole 21. An oil seal 23 is laminated in the stepped hole 21, and a cylinder end 24 is screwed and fixed to the opening thereof.

As shown in FIG. 1, the housing 10 is formed with a fitting hole 10b that is continuous with the through hole 10a and opens toward the piston 15 side, and has a larger diameter than the through hole 10a.
A spacer 30 through which the steering rod 11 is inserted is fitted into the fitting hole 10b. There is an extremely small gap between the spacer 30 and the fitting hole 10b and between the spacer 30 and the steering rod 11.
The movement in the radial direction is restricted by a predetermined amount or more.

An oil seal 32 is press-fitted into the fitting hole 10b with a certain margin, and this press-fitting is performed in the first
This is done using a press-fitting jig 40 shown in the figure. At one end of this press-fitting jig 40, there is a holding part 41 that protrudes in the axial direction and fits into the inner periphery of the spacer 30 and the oil seal 32 to hold them. A pressing surface 42 contacts the end surface of the oil seal 32 at a position, and a housing 10 at a position radially outwardly shifted relative to the pressing surface 42 and recessed toward the opposite side of the oil seal 32 relative to the pressing surface 42. A stopper surface 43 is formed in contact with the stopper surface 43, and an annular recess 44 is formed to allow the rubber of the oil seal 32 protruding between the stopper surface 43 and the pressing surface 42 to escape. The other end of the press-fit jig 40 is a press-fit device 50
The press-fitting device 50 is connected to the actuating rod 51 of the
is fixed to the fixed part.

Next, the operation will be explained based on the above-described configuration. The cylinder tube 16 assembled into the housing 10 is installed in a predetermined position, and the press-fitting jig 4 is installed.
A spacer 30 and an oil seal 3 are attached to the holding part 41 of 0.
Install 2. In this state, the press-fitting device 50 is operated to advance the press-fitting jig 40, and the spacer 30 is fitted into the fitting hole 10b. Furthermore, press-fit jig 40
When the oil seal 32 is moved forward, the oil seal 32 presses the
is pressed and press-fitted into the fitting hole 10b. In the process of press-fitting the oil seal 32, the oil seal 3
The rubber on the outer circumferential side of No. 2 is not press-fitted and protrudes toward the press-fitting jig 40, and this protruding rubber is removed from the press-fitting jig 40.
The housing 10 is allowed to escape into the gap 43 without being pinched between the stopper surface 43 and the end surface of the housing 10. This prevents the rubber from cutting. Press-fit jig 40
When the stopper surface 43 of the press-fitting jig 40 comes into contact with the end face of the housing 10, the press-fitting jig 40 stops moving forward, and the press-fitting jig 4
0 retreats, the press-fitting of the oil seal 32 is completed.

<Effects of the invention> As described above, the present invention forms a pressing surface that comes into contact with the end surface of the oil seal at one end of the press-fitting jig, and also forms one end of the housing at a position radially outward relative to this pressing surface. Since a stopper surface is formed in contact with the press-fitting jig and an annular gap is formed between the pressing surface and the stopper surface, the protruding rubber of the oil seal is not pinched between the stopper surface of the press-fitting jig and the end surface of the housing, and the annular gap is formed between the pressing surface and the stopper surface. This allows the rubber to escape into the gap, preventing problems such as those caused by the rubber being cut and the sealing function being impaired.

[Brief explanation of the drawing]

The drawings show an example of the implementation of the present invention.
The figure is an enlarged sectional view showing the main parts of the present invention, and FIG. 2 is a sectional view of a rack-and-pinion type power steering device. 10...Housing, 10a...Through hole, 10
b... Fitting hole, 11... Steering rod, 1
6...Cylinder tube, 30...Spacer, 3
2...Oil seal, 40...Press fitting jig, 41...
... Holding part, 42 ... Pressing surface, 43 ... Stopper surface, 44 ... Recess, 50 ... Press-fitting device, 51 ...
...Operating rod.

Claims (1)

[Scope of utility model registration request] A press-fitting jig used for press-fitting an oil seal into a fitting hole formed at one end of a housing, the press-fitting jig having a pressing surface that comes into contact with the end surface of the oil seal at one end of the press-fitting jig. A stopper surface that contacts one end of the housing is formed at a position shifted radially outward with respect to the pressing surface, and an annular recess is formed between the pressing surface and the stopper surface to release the rubber protruding from the oil seal. Features a pressing jig for oil seals.