JPH0612873U - Bearing seal - Google Patents

Abstract

(57) [Summary] (Modified) The present invention relates to a bearing seal that is mounted on a bearing and seals the inside and outside thereof, and that alleviates the pressure difference between the bearings. [Structure] The bearing seal A is provided with a through hole 3, and a ventilation sheet 4 is arranged in the through hole 3.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a bearing seal mounted on a bearing to seal the inside and the outside of the bearing, and more specifically to a bearing seal capable of reducing the pressure difference between the inside and the outside.

[0002]

[Prior art]

 Conventionally, a sealing material having ventilation holes has been used to provide air permeability to the inside and outside of the bearing in response to changes in atmospheric pressure due to the temperature inside the bearing. An example of this is shown in Japanese Utility Model Publication No. Sho 46-32492. The structure (shown in FIG. 3) as disclosed in the publication can be mentioned. In this structure, the outer peripheral edge 5 of the bearing a is fixed to the outer peripheral edge 5 and the inner peripheral edge 6 is applied to the inner ring a2 so as to be in contact with the bearing seal B. However, the vent hole 7 is provided at an appropriate position of the bearing seal B. A filter 8 such as felt is installed in this vent hole 7 to cope with the pressure difference between the inside and outside.

[0003]

[Problems to be solved by the device]

 However, in the felt type ventilation structure as described above, even if the breathing action is obtained, the invasion of water that promotes the formation of rust cannot be stopped, and the role as a sealing material may be abandoned. . That is, when the filter 8 such as felt itself gets wet and the water is gradually impregnated inside and the water is retained above a certain level, the water is easily drawn into the inside by the breathing action.

To avoid this, a seal ring (not shown) having a vent plug made of a porous material having fine pores has been developed as disclosed in Japanese Utility Model Laid-Open No. 48-43058. However, similarly to the above, it is not possible to completely prevent the generation of rust, for example, by allowing moisture to penetrate into the inside by aeration and suction from the impregnation of moisture. The present invention eliminates many of these drawbacks and prevents heat generation and clogging of the seal lip, which are the major drawbacks of the contact-sealing type bearing seal that forms a seal by contacting the bearing. The purpose is to provide a seal.

[0005]

[Means for Solving the Problems]

 The present invention will be described with reference to the drawings. As shown in FIG. 1, a bearing seal A having a fitting portion 1 mounted on a rotating bearing and fixed to the bearing a1 or a2 and a seal lip 2 slidingly contacting the bearing seal A is shown. There is provided a through hole 3 penetrating the inside and the outside of a part of the bearing seal A, and a ventilation sheet 4 formed by adhering a continuous porous polytetrafluoroethylene sheet 41 and a non-woven fabric 42 to each other is provided. It is characterized in that it is arranged in the through hole 3.

[0006]

[Action]

 The present invention, having the above-mentioned structure, has the following excellent effects. That is, the polytetrafluoroethylene sheet 41 used here in the present invention is a sheet-shaped polytetrafluoroethylene material that is stretched to have a fine porous structure, and has a fine void inside. The pores exist in a series with each other and the structural material has high thermal stability, fine filtration separation property, and excellent water repellency.

The polytetrafluoroethylene sheet 41 and the non-woven fabric 42 formed by compressing bristles and fibers are bonded to each other to form the ventilation sheet 4, so that the polytetrafluoroethylene sheet 41 having a large water contact angle becomes a capillary. It does not cause a phenomenon and shows high water repellency while allowing air to permeate through the continuous minute pores, and the non-woven fabric 42 located outside thereof also permeates air in the same manner as described above. There will be no difference, and the inside will be completely free of water. Of course, the polytetrafluoroethylene sheet 41 and the non-woven fabric 42 that form the ventilation sheet 4 exhibit high filter action and do not allow even fine dust to infiltrate scattered dust.

[0008]

【Example】

 In order to carry out the present invention, when the nonwoven fabric 42 is arranged on the outer side of the bearing a as shown in FIG. 1, clogging of the polytetrafluoroethylene sheet 41 due to fine dust is prevented, and this nonwoven fabric is also prevented. Positioning 42 inside prevents the grease, oil, etc. in the bearing a from coming into direct contact with the polytetrafluoroethylene sheet 41, and prevents clogging by oil in the continuous porous portion. Furthermore, in order to obtain each of the above-mentioned excellent effects, it is possible to dispose the non-woven fabric 42 on both sides of the polytetrafluoroethylene sheet 41, and this structure can be a perfect filter material for inside and outside. .

The present invention can be applied to the flat type bearing seal A as shown in FIG. 1 to the fitting type oil seal C as shown in FIG. Since the ventilation sheet 4 can be arranged apart from the above, the ventilation action without affecting other parts is achieved.

[0010]

[Effect of device]

 According to the present invention, since the bearing seal A itself has gas permeability, no negative pressure is generated from the inside of the bearing to the seal lip 2, and the seal lip 2 is prevented from being scraped and worn, and the seal life is greatly extended. Further, since the ventilation sheet 4 has high water repellency, it completely blocks moisture and protects the interior of the bearing from rust.

[0011]

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing another embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a conventional structure without using the present invention.

[0012]

[Explanation of symbols]

 A Bearing seal C Oil seal a Bearing 1 Fitting part 2 Seal lip 3 Through hole 4 Venting sheet 41 Polytetrafluoroethylene sheet 42 Nonwoven fabric

Claims (2)

[Scope of utility model registration request] 1. A bearing seal A having a fixed fitting portion 1 and a seal lip 2 in sliding contact with the bearing seal A. A bearing seal characterized in that a ventilation sheet 4 formed by laminating a polytetrafluoroethylene sheet 41 having a structure and a non-woven fabric 42 is provided in the through hole 3. 2. The bearing seal according to claim 1, wherein a non-woven fabric 42 is attached to both surfaces of the polytetrafluoroethylene sheet 41 to form a ventilation sheet 4.