JPS63312570A - Oil seal of outer periphery metal insertion type - Google Patents

Abstract

PURPOSE:To make it possible to fit the title oil seal smoothly and surely by providing a press-fitting part for press-fitting an oil seal into a housing with a desired fitting allowance on the base end side of an outer periphery of a reinforcing ring and also providing an insertion part with an outer diameter slightly smaller than the inner diameter of the housing on the tip side of the outer periphery part. CONSTITUTION:When an oil seal is fitted into a housing H, an insertion part 4b of the tip of the outer periphery part 4 of a reinforcing ring 1 is inserted into the housing H by a hand or with a pushing jig. In this case, since the insertion part 4b is formed into an outer diameter slightly smaller than the inner diameter of the housing H, it is possible to easily push the insertion part 4b into the housing H so as to stably position and maintain the oil seal. As the insertion part 4b is press-fitted with the use of a pushing jig or the like or by hammering with the above-mentioned state held, the outer periphery 4 of the reinforcing ring 1 is moved from the insertion part 4b to the press- fitting part 4a with respect to the inner surface of the housing H so that it is inserted and fixed in the press-fitting part 4a with a desired fitting allowance.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention relates to a peripheral metal fitting type oil seal in which the outer surface of the outer peripheral part of a reinforcing ring is fitted into a housing, and in particular, to improve the assemblability of the oil seal. It is about improvement.

"Prior art, problems to be solved by the invention" Generally,
In the type of oil seal that fits into the housing on the outer periphery of the metal reinforcing ring, the outer periphery is formed to have a uniform outer diameter with the required fitting allowance, as shown in Figure 2. Sealant is applied to the surface.

Therefore, when assembling it into a conventional oil seal housing of this type, it is not easy to fit it, and automobile manufacturers use a special pushing jig that applies strong pressure evenly to the entire circumference of the oil seal. However, other automobile maintenance and repair shops do not have such specialized jigs, so they use a hammer to hammer into the housing each time the engine is disassembled.

However, in the method of hammering in the housing, it does not bite into the housing, so when you hit one part, the other part lifts up, making it extremely difficult to fit. There were problems such as deformation of the

By the way, in the above-mentioned conventional outer periphery B"M combination type oil seal, the upper end of the outer periphery is generally arranged so that it can be assembled by smoothly sliding it in the lateral direction starting from the lower one when stacked vertically. An arcuate portion is formed in the arcuate portion, and a very small portion of the tip of this arcuate portion has an outer diameter smaller than the inner diameter of the housing. However, when assembling with a hammer, if the tip with a large contact angle with the housing slightly engages with the housing, it will not help at all to facilitate the fitting.

Therefore, the applicants have recently developed an oil seal in which the tip of the outer periphery of the reinforcing ring is tapered so that it gradually becomes smaller than the inner diameter of the housing toward the tip, as shown in Figure 3. It has become possible to drive in with a hammer, but the striking force and driving method vary depending on the worker, and the deformation of the oil seal after driving varies from person to person, so perfect driving cannot always be expected. There was a problem.

"Means for Solving the Problems" In order to solve the above-mentioned conventional problems, the present invention includes a crimp fitting part that crimp-fits to the housing with a required fitting allowance on the proximal end side of the outer peripheral part of the reinforcing ring. In addition, by providing an insertion part with an outer diameter slightly smaller than the inner diameter of the housing on the tip side of the outer periphery, smooth and reliable fitting can be achieved even by a fitting method in which the housing is hammered into the housing. We are proposing an external metal fitting type oil seal that makes this possible.

"Embodiments" Below, embodiments of the present invention shown in the drawings will be described.
The reinforcing ring l is made of a metal plate and is formed into an annular shape with a roughly L-shaped cross section, and a seal made of heat-resistant rubber such as fluoro rubber is attached to the diagonally upwardly bent inner peripheral edge of the roughly horizontal flange part 2. A lip 3 is formed, and an outer peripheral portion 4 rising from the flange portion 2 is provided.

The outer circumferential portion 4 is provided with a crimp fitting portion 4a that crimply fits into the housing H with a required fitting margin on its proximal end side, and an outer diameter dimension slightly smaller than the inner diameter of the housing H on its distal end side. An insertion portion 4b is provided.

Note that there is a small step portion 4 between the crimp fitting portion 4a and the insertion fitting portion 4b.
It is preferable to add a taper or radius in which the outer diameter gradually decreases from the crimp fitting part 4a to the insertion fitting part 4b. A bent portion 4d is formed which is bent into an arc shape, a conical shape, or a hook shape.

The insertion part 4b can be easily pushed into the housing H by hand or using a pushing jig or the like.

Furthermore, the outer diameter is set to such an extent that it will not rattle or easily fall off after being pushed in, and it is also set to have a fit 11 that is sufficient to stably hold the entire oil seal in the housing H after being pushed in.

A sealant is applied to the outer circumferential surface of the crimp fitting part 4a, and this sealant is preferably a sealant with good adhesion and compressive fluidity and low shearing force, such as a rubber latex such as acrylic rubber and low molecular weight tetrafluoroethylene. A compound containing fine resin powder is used.

Note that although sealant is not normally applied to the insertion portion 4b, it may be applied if necessary.

In addition, in the illustrated embodiment, the inserting portion 4b is formed by cutting the inner circumferential surface of this portion to facilitate bending, or by press forming at the same time as the drawing of the reinforcing ring 1, so that the plate thickness can be reduced. It is processed to be as thin as 1/2 to 273 times the thickness of the material.

Since it is possible to form the material plate with the same thickness, there is no particular need to make this part thinner than the crimp fitting part 4a.

"Operation of the Invention" When fitting the oil-sealed housing H constructed as described above, first insert the fitting part 4b at the tip of the outer peripheral part 4 of the reinforcing ring 1 into the housing H by hand or with a pushing jig or the like. Fits in.

At this time, since the fitting portion 4b is formed to have an outer diameter slightly smaller than the inner diameter of the housing H, this portion can be easily pushed into the housing H to stably position and hold the oil seal.

Then, in this state, press-fit using a pushing jig or the like, or
Alternatively, when it is pressed in by hitting it with a hammer, the outer peripheral part 4 of the reinforcing ring moves from the insertion fitting part 4b to the crimp fitting part 4a against the inner peripheral surface of the housing H, and is fitted with the required fitting distance in the crimp fitting part 4a. Fixed.

"Effects of the Invention" As described above, according to the present invention, in the outer periphery metal fitting type oil seal that fits and seals the outer periphery of the reinforcing ring into the housing, the required fitting is performed on the base end side of the outer periphery of the reinforcing ring. A crimp-fitting part is provided that is crimped-fitted to the housing with a mating margin, and an insertion-fitting part is provided on the tip side of the outer circumferential part with an outer diameter slightly smaller than the inner diameter of the housing, so when fitting the oil seal. First, the fitting part can be easily pushed into the housing to stably position and hold the oil seal, and in this state, it can be done extremely smoothly and reliably even when hit with a hammer as well as a press-fitting jig, regardless of individual workers. Moreover, it can be fitted into the housing without deforming the oil seal, and the ease of assembly can be greatly improved.

[Brief explanation of drawings]

1UA is a partial vertical cross-sectional view of an oil seal of the present invention, and FIGS. 2 and 3 are partial vertical cross-sectional views of a conventional oil seal reinforcing ring. l...Reinforcement ring, 2...Flange part. 4...Outer circumferential part, 4a...Crimp fitting part, 4b...Insertion fitting part, 4c...Step part. 4d...Bending part.

Claims (1)

[Claims] In an outer periphery metal fitting type oil seal that fits and seals an outer periphery of a reinforcing ring to a housing, a crimping fitting part that crimps and fits to the housing with a required fitting allowance on the proximal end side of the outer periphery of the reinforcing ring. An outer periphery metal fitting type oil seal characterized in that the outer periphery is provided with an insertion portion formed on the tip side of the outer periphery with an outer diameter slightly smaller than the inner diameter of the housing.