JPS59199232A - Surface treatment of oil seal - Google Patents

Abstract

PURPOSE:To enable an oil seal surface treating method high in hermetical sealing property and excellent in mass-productivity, by injecting steel spheres or glass spheres each having a proper particle size to the seal surface or the entire surface of an oil seal. CONSTITUTION:Particles 1 each having a proper particle size injected so as to have directionality are sprayed to the seal surface of an oil seal A to be allowed to reach the surface of said seal surface to impact the same by respective particles 1. At this time, the seal surface overcomes with the impact of the particles 1 and the surface film thereof is gradually destructed to form an uneven configuration. In addition, because the seal surface of the oil seal A is formed of an elastomer for retreaving the impact force of the particles in a pref. range, the valley part of the uneven part formed to said surface retrieves impact to show function for slowing down that a depth advances to a definite degree or more and destructing a protruded mountain part and an ideal fine aventurine uneven surface is formed. By this method, the uneven configuration can be controlled to desired roughness by bringing the particle size of the particles 1 to an arbitary value and roughness optimum in hermetical sealing can be formed to the seal surface in a mass-production system.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improving the sealing properties of oil seals, and more specifically to a method for surface treatment of oil seals. Conventionally, oil seals have sole lips made of an elastic material such as synthetic rubber. The tip of the sole lip slides into contact with the mating shaft to prevent lubricating oil from leaking to the outside. However, if the tip of the sole lip is too well finished, the lubrication As a result, the tip of the sole lip generates heat due to rotational friction, causing seizure and resulting in a defective sole.On the other hand, if the tip of the sole lip is rough, it causes oil leakage and impairs sealing performance. . In order to maintain the sealing properties of this oil sole, it is necessary that the seal lip surface and the contact surface of the mating shaft have an appropriate roughness with a certain range of voids.

In other words, if the roughness is too small, it will generate heat locally due to sliding, resulting in hardening or seizure, while if the roughness is too large, leakage or wear will occur. For seals, maximum roughness Rmax Q, 7-3. Although O3 level is preferable for sealing, it varies depending on the usage condition and size of the seal. Therefore, within a range of appropriate roughness, the sole lip contact portion has a low coefficient of friction, maintains a good oil film balance, and easily adapts to the mating shaft to provide a strong seal for a long period of time. Therefore, in order to form this appropriate roughness range on the seal lip, for example, there is a method of cutting the tip of the seal lip with a cutting tool to form a groove, a method of cutting the tip of the circumferential edge of the sole lip with a knife, or a method of forming an uneven part on the mold in advance. Attempts have been made to form an appropriate roughness on the surface of the sole lip using methods such as forming and molding. However, all of the above-mentioned methods have drawbacks such as being extremely poor in mass production, requiring special jigs for exclusive use, and requiring special skill to operate.

The present invention provides a surface treatment method for oil seals that eliminates these drawbacks, provides high sealing performance, and is suitable for mass production.

A detailed description will be given below with reference to the drawings.

As shown in the figures, the present invention is a surface treatment method for an oil seal A formed of an elastic body such as synthetic rubber or synthetic resin and interposed between a rotating side member and a stationary side member, the sole surface or Particles 1 made of hard material such as steel balls or glass balls with appropriate particle size on the entire surface
This is a method for surface treatment of oil seal A by spraying.

This treatment method has the following features and exhibits an excellent sealing effect. That is, by spraying the granules 1 having an appropriate particle size that are jetted in a certain direction onto the sole surface of the oil seal A, the granules 1 reach the surface of the sealing surface and the sole surface is exposed to the granules 1. Each of them knocks.

At this time, the sole surface succumbs to the impact of the injected particles 1, and the melt-resistant surface film of each particle 1 is gradually destroyed, forming an uneven shape. Furthermore, since the sole iLt of the oil seal A is made of an elastic material that alleviates the impact force of the injected particles within a desirable range, the troughs of the uneven parts formed on the surface of the oil seal A soften the impact and exceed a certain level. It works to slow down the progression of depth and destroy the protruding peaks to form an ideal finely uneven surface with a satin finish. In addition, oil seal A has the optimum roughness for sealing, such as by making the grains 1 particles of any size, so that the uneven shape can be controlled to the desired roughness.
In the case of oil seal A made of synthetic rubber, the effect of finely destroying the coating on the sole surface is due to the filler compounded in the synthetic rubber. The end face of the oil seal A is exposed and each of the exposed fillers acts on the rotating side member, and the above-mentioned effect forms a fine matte surface, which makes it easier to install the oil seal A at the location where it is sealed. During operation, the sealing surface always maintains a well-balanced and appropriate oil film, so it easily adapts to the mating shaft and good sealing performance can be maintained for a long period of time.

In addition, in this surface treatment method, it is possible to provide a desired roughness and a large amount of processing capacity by changing the shape, particle size, particle amount, ejection time, etc. of the nozzle 2 that ejects the granules 1, and further improve elasticity. Compared to conventional lip cutting methods and methods that use lip cutting, it is possible to process a large number of seals at the same time, such as finishing the mold defects such as mold defects that are inevitable when forming the body. This greatly improved mass productivity by shortening work time and reducing manufacturing costs.

In addition, this surface treatment method allows the formulation of the base material to be given sufficient consideration to many important items such as heat resistance and weather resistance, rather than being limited only to sealing power. Similarly, an optimal shape can be designed without satisfying the above-mentioned important items.

As explained above, the present invention is an ideal oil seal that can easily and quickly form a satin-like seal surface that is most suitable for sealing, which has not been seen in conventional oil seals, and in large quantities. This is a surface treatment method for seals.

[Brief explanation of drawings]

The drawing is a perspective view of injecting the granules of the present invention onto an oil seal. A... Oil seal... Granules 2... Nozzle patent applicant Uchiyama Kogyo Co., Ltd.

Claims (1)

[Claims] Granules formed of a hard material on the seal surface or entire surface of an oil seal formed of an elastic body such as synthetic rubber or synthetic resin that is interposed between a rotating side member and a stationary side member and sealing both members. A surface treatment method for oil seals that emits strong radiation and makes the surface uneven.