JPH0557523U - Oil seal - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] The present invention improves the wearability by integrating an oil seal composed of a combination of a plurality of members. [Structure] The oil seal has a shape in which a radial lip 4 made of PTFE is protected by a damper portion 6 of a slinger B, and prevents excessive deformation and damage of the radial lip 4.
In addition, after mounting the oil seal on the housing 1, the housing 1 is mounted on the engine body, and at the same time, the tubular portion 5 of the slinger B is inserted into the shaft 2. At this time, the slinger B is pushed to the outside and makes a small movement, but the folded back damper portion 6 of the tubular portion 5 of the slinger B comes into contact with the sealing element A to prevent the movement thereof. The slinger B moves as a unit and the tubular portion 5 is inserted into the shaft 2. Next, the boss 9 which is mounted on the shaft 2 from the outside is pressed against the swinging plate 7 of the slinger B to guide the slinger B to an appropriate position, and the mounting and fixing of the boss 9 and the oil seal are simultaneously completed.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a sealing device that is mounted between members that rotate with respect to each other and seals the inside and the outside between the members, and more particularly, to improving the shape of an oil seal formed by combining a plurality of members.

[0002]

[Prior Art]

 2. Description of the Related Art Conventionally, an oil seal used for a crankshaft of an engine is generally first press-fitted into a housing and then mounted on a shaft. A general example of this type will be described in detail with reference to the drawings. A radial lip (4) and a dust strip (3) are provided on the inner peripheral side having a fitting portion on the outer peripheral side as shown in FIG. A simple oil seal having a plurality of sealing means such as) is used.

[0003]

[Problems to be solved by the device]

 However, the inversion of the seal lip, which may occur when installing the oil seal, and lip damage due to burrs on the shaft chamfer, etc., rank high in the oil seal failure. On the other hand, the sealing environment is becoming more and more difficult due to the downsizing and high performance of engines, and the seal lip material for oil seals is being upgraded to resin materials such as PTFE rather than conventional rubber elastic bodies. In the case of materials, the above problems when mounting and the problems that the sealing performance is lost if the material is inadvertently largely deformed because its elasticity is several steps lower than that of rubber, etc. are factors that prevent its adoption. Moreover, even when considering maintenance in the market, it is the current situation that sufficient reliability cannot be ensured with resin materials that require careful handling.

The present invention eliminates such a serious defect and uses a material such as PTFE that requires careful handling for the seal lip in order to improve the sealing performance. However, the handling is the same as before and the reliability is higher than the conventional oil. Intended 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. 2, the present invention comprises a plurality of members mounted between a housing (1) and a shaft (2) to form a seal between the two members (1) and (2). As shown in FIG. 1, an oil seal is a seal element (A) having a dust lip (3) mounted on the housing (1) and located on the atmosphere side and a radial lip (4) made of PTFE in the back. And the radial lip (4) comes into contact with the shaft (2) to form a fitting tubular portion (5), and the inner end of the tubular portion (5) is folded back to form a damper portion (6). In combination with the slinger (B), the end of which is close to the sealing element (A), and to the cylinder portion (5) on the atmosphere side of the slinger (B) in the radial direction close to the dust lip (3). Fit the shaking plate (7) extending to the above-mentioned sealing element ( ) Is a feature that is integrated with. Further, as shown in FIG. 1, the inner periphery of the tubular portion (5) of the slinger (B) is covered with an elastic body such as rubber, and a small projection (8) is formed on the fitting surface to form the shaft (2). It is characterized in that the presser force of the slinger (B) is set to be smaller than the fitting force of the seal element (A).

[0006]

[Action]

 The present invention has the above-described structure and has the following excellent effects. That is, the oil seal having the combination shown in FIG. 1 has a shape in which the radial lip (4) made of PTFE is protected by the slinger (B), and the radial lip (4) is prevented from being excessively deformed or damaged. To prevent. Further, when mounting the same, as shown in FIG. 2, first of all, the oil seal is mounted on the housing (1), and then the housing (1) is mounted on the engine body and at the same time, the tubular portion (5) of the slinger (B) is mounted. Is inserted into the shaft (2). At this time, the slinger (B) is pushed to the outside to make a small movement, but the folded back damper part (6) of the tubular part (5) of the slinger (B) is attached to the sealing element (A). In order to come into contact with each other and prevent their movement, both (A) and (B) move integrally and the tubular portion (5) is inserted into the shaft (2). Next, a boss (9) such as a flywheel or a pulley mounted on the shaft (2) from the outside is pressed against the shaker plate (7) of the slinger (B) (arrow) to attach the slinger (B). ) To an appropriate position, and the mounting and fixing of the boss (9) and the oil seal are completed at the same time.

[0007]

【Example】

 In the case of mounting the oil seal on the housing (1) described above, since the shaker plate (7) of the slinger (B) has an integral combination shape for holding the seal element (A), the seal element (A) It suffices to use a simple insertion jig that can press-fit into the housing (1), and even when it is attached to the shaft (2), it can be inserted and fixed by passing it through the tubular portion (5) of the slinger (B), and the boss (9) Since it is placed in the proper position by fitting, it can be mounted very easily. The shape of the damper portion (6) can be reduced by making a simple tubular shape, or by providing notches or irregularities as shown in FIGS. 1 and 2.

In the operation with the oil seal attached, the shake-off plate (7) located on the outer end side (atmosphere side) prevents dust from entering and muddy water from adhering, and the dust lip located on the inner side. (3) shows a strong sealing force. Furthermore, the radial lip (4) made of PTFE arranged in the back of the damper prevents leakage of the lubricating oil inside, and the frictional heat generated on the sliding surface of the lip (4) is the damper part (6) and the swing plate (7). It immediately diverges and cools, exerting a strong sealing force and durability, forming an oil seal with high performance as a whole. Also, setting the gap between the seal element (A) and the damper part (6) to the maximum eccentricity during operation prevents the radial lip (4) from being excessively deformed beyond the gap, which is a useful dimension. It will be set.

[0009]

[Effect of the device]

 According to the present invention, it is possible to accurately and fixedly mount with a simple mounting jig, and in the mounting work, the elastic seal lip (4) can be mounted safely and in a short time without significantly deforming or damaging it. However, since it exhibits high sealing performance, it can even achieve a long service life. This effect makes it possible to install it even if it is not a skilled professional worker, and has a great impact on maintenance management.

[0010]

[Brief description of drawings]

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

FIG. 2 is a sectional view showing an embodiment in which the present invention is mounted.

FIG. 3 is a sectional view of a conventional structure not using the present invention.

[0011]

[Explanation of symbols]

 A Seal element B Slinger 1 Housing 2 Shaft 3 Dustrip 4 Radial lip 5 Cylindrical part 6 Damper part 7 Shaking plate 8 Small protrusion 9 Boss

Claims (4)

[Scope of utility model registration request] 1. An oil seal comprising a plurality of members mounted between a housing (1) and a shaft (2) to form a hermetic seal between the two members (1) and (2). The dust lip (3) located on the side and the back P
A sealing element (A) having a radial lip (4) made of a resin material such as TFE, and a tubular portion (5) for fitting with a shaft (2) with which the radial lip (4) comes into contact, and A cylinder on the atmosphere side of the slinger (B) is combined with a slinger (B) in which the inner end of the cylinder (5) is folded back and the end of which forms a damper portion (6) close to the sealing element (A). An oil seal characterized in that a shaker plate (7) close to the dust lip (3) is fitted into the part (5) to be integrated. 2. A small projection (8) made of an elastic body is formed on the fitting surface of the slinger (B) to allow a tight margin with the shaft (2) to seal the force input of the slinger (B). The oil seal according to claim 1, wherein the oil seal is set to be smaller than the fitting force of the element (A). 3. The oil seal according to claim 1, wherein the sealing element (A) and the slinger (B) are integrated by a shake plate (7). 4. The oil seal according to claim 1, wherein the gap between the seal element (A) and the damper part (6) is set to the maximum eccentric amount during operation.