JPH01307571A - Lip seal device - Google Patents

Abstract

PURPOSE:To simplify the seal device pull-out procedure by forming an engagement part which is engaged with a case pull-out tool, on the internal face of the case annular groove of a seal member which seals between a housing and a case. CONSTITUTION:The clearance between a housing 1 and a case 2 is sealed with a sealing member 7. An annular groove 6 in which a sealing member 7 falls is formed in the case 2 and a retaining part 13 which retains a pull-out tool 12 is formed in the internal face of said annular groove 6. The retaining part 13 has a shallow annular groove formed on a small-diameter part 2b and the internal face and the small-diameter part 2b is tapered. The end face of the pull-out tool 12 has an engagement projection having a slit and able to be reduced axially in diameter. By the insertion of the tool 12, the engagement projection goes inward along the tapered face of the small-diameter part 2b and is increased in diameter by the shallow annular groove until engaged with the small-diameter part 2b. The pull-out of the case 2 may then be executed easily.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a lip seal device that includes a lip seal that slides into contact with a rotating shaft.

"Prior Art" Conventionally, a lip seal device includes a case fitted in a housing, an annular groove formed on the outer circumferential surface of the case,
a sealing member provided in the annular groove to seal between the case and the housing; and a rotating shaft having an outer circumference attached to the case and an inner circumference curved toward the sealed fluid side and penetrating the case. A lip seal that is in sliding contact with the outer circumferential surface of the
Publication No. 58).

Since this type of lip seal device is fitted into the housing, it is necessary to pull out the lip seal device from the housing in the event of a failure or the like. For this reason, in the lip seal device described in the above publication, an auxiliary member for pulling out is provided in the case, and a pulling jig is engaged with the auxiliary member to pull it out from the housing.

In addition, as another structure, a structure has been proposed in which an engaging part is formed at the end of the case and projects radially inward, and the pulling jig is engaged with this engaging part ( Utility Model Application Publication No. 61-94655).

[Problems to be Solved by the Invention] However, in a case in which an engaging portion that protrudes radially inward is formed at the end of the case, the axial length of the case is reduced by the amount of forming the engaging portion. The disadvantage is that it becomes long. On the other hand, the case provided with an auxiliary member/material for pulling out can prevent the axial length of the case from increasing, but has the disadvantage that the number of parts increases and the cost increases accordingly.

"Means for Solving the Problem" In view of such circumstances, the present invention includes a case fitted in a housing, an annular groove formed on the outer peripheral surface of the case,
a sealing member provided in the annular groove to seal between the case and the housing; and a rotating shaft having an outer circumference attached to the case and an inner circumference curved toward the sealed fluid side and penetrating the case. a lip seal that is in sliding contact with the outer peripheral surface of the case, the inner peripheral surface of the case opposite to the annular groove being engaged with a pulling jig for pulling out the case from the housing. In this embodiment, an engaging portion is formed.

"Function" As in the above configuration, by forming the engaging part on the inner peripheral surface of the case opposite to the annular groove, it is possible to prevent the axial dimension of the case from increasing, and also to reduce the number of parts. Since the cost does not increase, the cost increase can be minimized.

``Embodiment'' The present invention will be described below with reference to an illustrated embodiment. In FIG.
and a second lip seal 4, the inner circumferential portion of each lip seal 3.4 is curved from the radial direction toward the sealed fluid side, that is, to the left in the axial direction, and each tip is connected to the rotating IrIb 5 passing through the case 2. It is brought into contact with the outer circumferential surface by its own elasticity, and each sliding contact portion is sealed.

The first lip seal 3 on the sealed fluid side has an annular groove 3a formed in its sliding surface with the rotating shaft 5, and the annular groove 38
By bringing the tip portion into close contact with the rotation @5 more uniformly, leakage of the sealing fluid is effectively prevented, especially when the rotation is stopped.

The generally cylindrical case 2 has a large diameter part 2a and a small diameter part 2b, and the end of the small diameter part 2b, that is, the left end in FIG. 1 is bent radially outward to form a flange part 2c. An annular groove 6 is formed on the outer periphery of the case 2 by the flange portion 2c, the small diameter portion 2b, and the stepped portion 2d between the large diameter portion 2a and the small diameter portion 2b. A sealing member 7 is fitted into the annular groove 6 to seal the housing 1 and the case 2.

Further, a right end portion of the large diameter portion 2a is bent radially inward to form a caulked portion 2e, and this caulked portion 2e and the step portion 2d form engaging end surfaces 2f and 2g that face each other in the axial direction. ing. A sealing member l in which a plate 8, the first lip seal 3, and a rigid plate 9 such as a metal washer are buried between the engaging end surfaces 2f and 2g in order from the stepped portion 2d side.
O1 The second lip seal 4 and the plate 11 are interposed, and the straw is integrally connected to the engaging end surfaces 2'' and 2g.

However, a shallow annular groove is formed in the case 2 on the inner circumferential surface on the opposite side to the annular groove 6, that is, on the inner circumferential surface of the small diameter portion 2b, and an engagement for engaging the annular groove with the extraction jig 12 is formed. Joint part 13
It is said that

As shown in FIG. 2, the drawing jig 12 includes a stepped cylindrical member 15 and a shaft member 16 screwed into the cylindrical member.
It is equipped with The stepped cylindrical member 15 includes a large diameter portion 17, a medium diameter portion 18, and a small diameter portion 19 formed in this order from one end to the other. An engaging protrusion 20 that protrudes from and engages with the engaging portion 13 is formed.

Further, a plurality of slits 21 are formed in parallel with the axial direction from the medium diameter portion 18 to the tip of the small diameter portion 19,
A tapered surface 22 is formed on the inner circumferential surface of the medium diameter portion 18, which is narrower on the side of the small diameter portion I9.

Then, a tapered surface 23 is formed at the tip of the shaft member 16 without contacting the tapered surface 22, and a handle 24 attached to the distal end of the shaft member 16 is rotated to form a tapered surface 23 on the tip of the shaft member 16. By pressing into contact with the tapered surface 22 of the cylindrical member 15, the engaging protrusion 20 can be expanded radially outward and engaged with the engaging portion 13.

Therefore, as is clear from the above configuration, the lip seal device can be pulled out from the housing 1 by engaging the engagement protrusion 20 of the extraction jig 12 with the engagement portion 13. In the lip seal device, the engaging portion 13 is formed on the inner circumferential surface of the lip seal device by utilizing the portion in which the annular groove 6 is formed. The directional dimension does not become long, and the number of parts does not increase.

Next, FIG. 3 shows another embodiment of the present invention. In this embodiment, a groove is partially formed in the circumferential direction on the inner circumferential surface of the case 2 on the opposite side to the annular groove 6. A plurality of engaging portions 13° consisting of through holes are formed. It is clear that even in such a configuration, the same effects as those described above can be obtained.

In short, the engaging portion 13.13' may have any shape as long as it can be engaged with the extraction jig 12. For example, in addition to the annular groove or through hole described above, it may be a projection. Good too.

[Effects of the Invention] As described above, according to the present invention, the lip seal device can be pulled out from the housing without increasing the axial dimension of the case or increasing the number of parts.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the present invention, FIG. 2 is a half sectional view of a drawing jig, and FIG. 3 is a sectional view showing another embodiment of the invention.

Claims (1)

[Scope of Claims] A case fitted into a housing, an annular groove formed on the outer peripheral surface of the case, and a seal member provided in the annular groove to seal between the case and the housing; A lip seal device having an outer circumferential portion attached to the case, and a lip seal having an inner circumferential portion curved toward the sealed fluid side and slidably in contact with the outer circumferential surface of a rotating shaft passing through the case, the lip seal having an annular shape of the case. A lip seal device characterized in that an engaging portion is formed on an inner circumferential surface on the opposite side of the groove to engage with a pulling jig for pulling out the case from the housing.