JPS6221814Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pressure-resistant oil seal made of fluororesin.

In general, oil seals have the physical properties necessary for oil seals such as wear resistance, heat resistance, pressure resistance, etc., as well as excellent chemical resistance, corrosion resistance, bacterial resistance, etc., and are highly durable. It is desirable that the elastic contact followability to the member to be sealed is always good and that the desired sealing function can be achieved over a long period of time.

By the way, focusing on the fact that fluororesin possesses the above-mentioned properties, a seal lip of an oil seal made of fluororesin has already been published in Japanese Patent Publication Publication No. 1983-
No. 36862, for example, as shown in Figure 1, a coil spring 2 is built into a seal lip 1 made of fluorine resin, and it almost completely satisfies all usage conditions as an oil seal. .

That is, since the coil spring 2 is built-in from the viewpoint of corrosion resistance, the problem of corrosion of the object to be sealed is successfully solved.

However, oil seals are used at increasingly high rotation speeds,
Currently, it is necessary to meet the demands for products that can withstand high pressure. Therefore, in order to meet the demand for oil seals that can withstand even higher pressures,
The pressure-resistant oil seal made of fluorocarbon resin of the present invention is an improvement on the above-mentioned fluorocarbon resin oil seal.

In the first place, the seal lip of a fluorocarbon resin oil seal is made of fluorocarbon resin, so compared to a rubber seal lip, the material has higher rigidity and less deformation under pressure, so it has better pressure resistance. However, on the other hand, it also has the disadvantage of poor initial familiarity. If the purpose is simply to suppress deformation due to pressure, it is sufficient to increase the thickness of the seal lip, but since the oil seal must constantly be in elastic contact with the shaft during operation to maintain followability. , it is not possible to increase the thickness of the seal lip by that much, and it is necessary to keep it at an appropriate thickness.

In addition, in the case of high-pressure seals, oil is sucked into the oil chamber by suction during rotation, but when the lip is stationary, the deformation that it received during high pressure cannot be quickly returned to its original state, so oil leakage is slightly reduced. This may occur.

The present invention was devised for the purpose of preventing the slight oil leak caused by the above-mentioned initial conformability and the slight oil leak when the vehicle is stationary.

That is, in this invention, as shown in FIG. 2, the inner periphery of the L-shaped reinforcing ring 3 is extended to form a truncated cone shape for pressure resistance, and the deformation of the seal lip 4 is backed up and suppressed, and the truncated cone surface 5
The upper end 6 of the bearing is provided with an auxiliary lip 7, which is made of sintered rubber and always elastically contacts the rotating shaft with a certain amount of interference. (This auxiliary lip 7 has the same amount of interference as the dust lip of a general oil seal.) With this configuration, the action of the auxiliary lip 7 prevents the seal lip 4 from slipping due to insufficient initial fit.
Since the auxiliary lip 7 prevents slight leakage from the seal lip 4, there is an advantage that the "break-in" period, which previously took a considerable amount of time, can be significantly shortened, and since the auxiliary lip 7 prevents slight leakage from the seal lip 4 even when the engine is stationary, a more perfect oil seal can be achieved.

The pressure-resistant oil seal made of fluorine resin of this invention is a revolutionary product that is excellent not only in wear resistance, heat resistance, and corrosion resistance, but also in eccentricity resistance and pressure resistance.
It is possible to expand the scope of application of conventional oil seals. Therefore, it can be applied to locations where mechanical seals have conventionally been used, and since the number of parts is small and the structure is compact, the product is inexpensive and is advantageous in terms of economy.

[Brief explanation of drawings]

FIG. 1 is a half vertical side view showing a conventional example, and FIG. 2 is a half vertical side view showing an embodiment of the present invention. 3...Reinforcement ring, 4...Seal lip, 5...Friss-conical surface, 6...Upper end, 7...Auxiliary lip.

Claims (1)

[Scope of utility model registration request] In a pressure-resistant oil seal with a coil spring built into the seal lip made of fluorine resin, the inner circumference of the L-shaped reinforcing ring is extended to form a truncated conical shape, and the upper end of the truncated conical surface A pressure-resistant oil seal characterized by a rubber auxiliary lip baked into the part that makes elastic contact with the rotating shaft at all times with a tightness.