JPH0717891Y2 - Oil seal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of use) The present invention relates to an oil seal suitable for being applied to a portion where an engine crankshaft penetrates a crankcase.

(Prior Art) An example of a conventional oil seal of this type is shown in FIG.

The crankshaft 1 penetrates through a through hole 3 formed in the crankcase 2, and its tip projects to the outside. A cover 4 that covers the gap between the outer peripheral surface of the crankshaft 1 and the inner peripheral surface of the through hole 3 is fastened to the outer surface of the crankcase 2 with bolts 5 and washers 6. A disk-shaped slinger 7 extending in a plane orthogonal to the crankshaft 1 is fixed to the crankshaft 1.

The cover 4 has a cylindrical portion 4a through which the crankshaft 1 penetrates, and a seal member 6 is fixed to the corners of the cylindrical portion 4a and the flat plate portion 4b adjacent thereto by baking.

The seal member 6 has a lip extending inwardly toward the slinger 7 and having its tip slidingly contacting the outer surface of the slinger 7.
6a and an oil pan 6b extending toward the outer peripheral surface of the crankshaft 1 are integrally formed.

A recess 8 is formed at a corner between the outer surface of the crankcase 2 and the inner peripheral surface of the through hole 3, and an O-ring 9 is fitted into the recess 8 and the O-ring 9 is connected to the inner surface of the cover 4. Bottom of the recess 8
The oil is prevented from leaking from the gap between the outer surface of the crankcase 2 and the inner surface of the cover 4 by narrowing the pressure between the crankcase 2 and 8a.

(Problems to be Solved by the Invention) In the above-mentioned conventional oil seal, since the O-ring 9 is disposed in the recess 8, not only the cost of the O-ring 9 increases but also the O-ring 9 is recessed in the recess 8. There was a problem that it took a lot of man-hours to fit it inside.

(Means for Solving the Problems) The present invention has been proposed to solve the above problems, and its gist is to provide the rotating shaft on an outer surface of a case having a through hole through which the rotating shaft penetrates. A cover that covers the gap between the outer peripheral surface of the and the inner peripheral surface of the through hole is fastened, and the cover extends inward toward the slinger fixed to the rotating shaft, and the tip of the cover slidably contacts the outer surface of the slinger. In an oil seal in which a seal member formed by integrally molding a lip and an oil pan extending toward the rotating shaft is baked,
It is fitted in a recess formed at the corner between the outer surface of the case and the inner peripheral surface of the through hole, and extends inwardly and obliquely toward the axis of the rotary shaft, the tip of which is recessed. An oil seal is characterized in that a second lip that comes into pressure contact with the bottom surface of the place is integrally formed with the seal member.

(Operation) Since the present invention has the above-mentioned structure, the second lip is fitted in the recess by fastening the cover to the outer surface of the crankcase, and the tip of the second lip is pressed against the bottom surface of the recess. To be done.

(Embodiment) One embodiment of the present invention is shown in FIGS.

The seal member 6 is extended in the radial direction, and a second lip 6c is integrally formed on the outer peripheral edge of the seal member 6.

When the cover 4 is fastened to the outer surface of the crankcase 2 with the bolt 5 and the washer 6, this second lip is automatically
6c fits in the recess 8, and its tip is pressed against the bottom surface 8a of the recess 8. Further, since the second lip 6c extends inward and obliquely toward the axis of the crankshaft 1, its tip is located on the bottom surface 8a of the recess 8 when pressure in the crankcase 2 is applied. It will be pressed further.

Thus, the oil leakage from the gap between the outer surface of the crankcase 2 and the inner surface of the cover 4 is reliably prevented by the second lip 6c. Further, when the seal member 6 is baked on the cover 4, the second lip 6c is integrally molded with the lip 6a and the oil receiver 6b at the same time, and the cost for baking on the inner surface of the cover 4 hardly increases.

Other configurations are similar to those of the conventional one shown in FIG. 4, and corresponding members are designated by the same reference numerals.

Of course, the present invention can be widely applied not only to the engine but also to a portion where the rotating shaft penetrates the case.

(Effect of the Invention) In the present invention, the inner surface of the crankcase and the inner peripheral surface of the through hole are fitted inward in the recesses formed at the corners,
Moreover, since the second lip, which extends obliquely toward the axis of the rotary shaft and has its tip pressed against the bottom surface of the recess, is formed integrally with the seal member, it is possible to omit the expensive O-ring required conventionally. Moreover, it is possible to omit the labor for mounting the O-ring. The second lip is automatically fitted into the recess by fastening the cover to the outer surface of the crankcase, and the tip of the second lip is pressed against the bottom surface of the recess to save cost and man-hours. .

[Brief description of drawings]

1 to 3 show one embodiment of the present invention, FIG. 1 is a longitudinal sectional view of an essential part, FIG. 2 is a partial longitudinal sectional view showing a state before attachment of a second lip, Figure 3 shows the second part when installed
FIG. 4 is a partial vertical sectional view showing a state of the lip of FIG. FIG. 4 is a vertical sectional view showing an example of a conventional oil seal. Rotating shaft …… 1, through hole …… 3, case …… 2, cover ……
… 4, slinger …… 7, lip …… 6a, oil pan …… 6b,
Recess …… 8, second lip …… 6c

Claims (1)

[Scope of utility model registration request] 1. A cover for fastening a gap between an outer peripheral surface of the rotary shaft and an inner peripheral surface of the through hole is fastened to an outer surface of a case having a through hole through which the rotary shaft passes, and the rotary shaft is attached to the cover. In the oil seal in which a seal member formed by integrally molding a lip that extends inward toward a fixed slinger and a tip of which slidably contacts the outer surface of the slinger and an oil receiver extending toward the rotary shaft is baked, Of the outer surface of the through hole and the inner peripheral surface of the through hole are fitted in the recess formed inward, and extends obliquely toward the axis of the rotary shaft, and the tip of the recess is formed. An oil seal, characterized in that a second lip, which comes into pressure contact with the bottom surface, is formed integrally with the seal member.