JP2017089829A - Sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device capable of suppressing deterioration of service life of a side lip due to movement of a slinger with which the side lip slidably contacts.SOLUTION: A seal member 2 of a sealing device 1 includes: a core metal part 3 opened to an external side B and having a cross section formed into a U shape; a main lip 62 and an auxiliary lip 63 fixed to an axial outside end part of a small-diameter cylindrical part 33 on a radial inside of the core metal part 3, and sliding on an outer peripheral surface 81a of a shaft 81; and a side lip 64 fixed to an inner peripheral surface 51a of a large-diameter cylindrical part 31 on a radial outside of the core metal part 3 and a side surface 52a on an opening depth side of the core metal part 3, and sliding on a slide surface 12a of a slinger 10. A space part C is sectioned and formed by the side lip 64, the slinger 10, the outer peripheral surface 81a of the shaft 81, the auxiliary lip 63, an outer peripheral surface 43b of the small-diameter cylindrical part 33 and the side surface 52a on the opening depth side of the core metal part 3.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a shaft seal portion of various devices, and more particularly to a sealing device used for a differential side of an automobile.

  As shown in FIG. 2, a conventional sealing device used for the differential side of an automobile has a foreign space such as muddy water from the outer side 122 of the housing 210 in an annular space formed between the shaft 200 and the housing 210 that rotate relative to each other. In order to prevent intrusion into the inner side 121, a seal member 100 mounted on the housing 210 and a slinger 110 disposed on the outer side 122 than the seal member 100 and mounted on the shaft 200 are provided. Yes.

  The seal member 100 includes a core bar 101 having a substantially U-shaped cross section that is open to the inner side 121, a main lip 102 and an auxiliary lip 103 that are fixed to the inner side in the radial direction of the core bar 101 and are in sliding contact with the outer peripheral surface of the shaft 200, A side lip 104 that is fixed to the outer side 122 of the cored bar 101 and extends obliquely outward in the radial direction of the outer side 122 is provided. In recent years, this sealing device causes the side lip 104 to come into sliding contact with the slinger 110 with an increase in demand for high sealing (for example, see Patent Document 1).

JP 2007-225064 A

  In the sealing device, the side of the slinger 110 moves back and forth in the axial direction (thrust movement) between the solid line position and the two-dot chain line position in the figure with respect to the seal member 100 during operation. The volume of the space 123 formed by the lip 104, the slinger 110, the outer peripheral surface of the shaft 200, and the auxiliary lip 103 may vary. In this case, when the volume of the space portion 123 becomes small, the space portion 123 becomes positive pressure, and the air in the space portion 123 flows out from between the tip of the side lip 104 and the slinger 110 to the external side 122. And the space part 123 becomes a negative pressure by the volume of the space part 123 becoming large after that.

  When such a negative pressure is generated, the area of the sliding contact portion of the side lip 104 with the slinger 110 increases, so that the temperature rises with an increase in torque, resulting in insufficient lubrication in the sliding contact portion. Further, as the reaction force of the side lip 104 increases, the torque (temperature) further increases, and the wear of the sliding contact portion of the side lip 104 is promoted. For this reason, when the said negative pressure generate | occur | produced, the lifetime of the side lip 104 fell and there existed a problem that the function which prevents the foreign material penetration | invasion to the space part 123 fell.

  This invention is made in view of such a problem, and provides the sealing device which can suppress that the lifetime of a side lip falls due to the movement of the slinger which a side lip slidably contacts. Objective.

  The sealing device of the present invention is attached to the housing in order to prevent foreign matter from entering the inside from the outside of the housing in the annular space formed between the shaft and the housing that rotate relative to each other. A sealing member, and a slinger that has a sliding contact surface extending in a radial direction on the outer side of the sealing member and is attached to the shaft. A core metal portion having a substantially U-shaped cross section that is open to the main body, a main lip that is fixed to the outer end surface in the axial direction of the small-diameter cylindrical portion on the radially inner side of the core metal portion, and that is in sliding contact with the outer peripheral surface of the shaft; An auxiliary lip fixed to the outer end of the cylindrical portion in the axial direction and in sliding contact with the outer peripheral surface of the shaft on the outer side of the main lip, and an inner peripheral surface of the large-diameter cylindrical portion on the radially outer side of the cored bar portion And opening the cored bar A side lip fixed to the back side surface and in sliding contact with the sliding contact surface of the slinger, the side lip, the slinger, the outer peripheral surface of the shaft, the auxiliary lip, the outer peripheral surface of the small diameter cylindrical portion, and A space portion is defined by a side surface on the back side of the opening.

  According to the present invention, the space portion includes, in addition to the side lip, the slinger, the outer peripheral surface of the shaft, and the auxiliary lip, the outer peripheral surface of the small-diameter cylindrical portion in the substantially U-shaped cored bar portion opened to the outside, Further, a partition is formed by the side surface on the back side of the opening. As a result, the volume of the space portion can be increased in the axial direction as compared with the volume of the conventional space portion 123 (see FIG. 2). Therefore, even if the volume of the space portion changes due to the thrust movement of the slinger. The rate of change can be reduced. As a result, the positive pressure value and the negative pressure value in the space portion can be reduced, and wear of the sliding contact portion of the side lip with the slinger can be suppressed. Therefore, it is possible to suppress the life of the side lip from being reduced due to the movement of the slinger that is in sliding contact with the side lip.

  The core metal portion includes a first large-diameter cylindrical body that extends in the axial direction along an inner peripheral surface of the housing, and a first annular ring that extends radially inward from an axially inner end portion of the first large-diameter cylindrical body. And a first cored bar having a first small-diameter cylindrical body that extends axially outward from an inner peripheral end of the first annular body, and the first small-diameter cylindrical body constitutes the small-diameter cylindrical part; A second cylindrical body fitted and fixed to the inner peripheral surface of the first large-diameter cylindrical body, and extending radially inward from an axially inner end of the second cylindrical body, and the first annular body A second metal core having a second annular ring fixed to the side surface on the outer side, and an inner peripheral surface of the second cylindrical body constitutes an inner peripheral surface of the large-diameter cylindrical portion, It is preferable that the outer side surface of the bicyclic ring constitutes the opening inner side surface.

  In this case, the main lip and the auxiliary lip are fixed to the first small-diameter cylindrical body (small-diameter cylindrical portion) of the first core metal, and the side lip is fixed to the second annular body of the second core metal. By fitting and fixing the second core metal with the side lip fixed to the first core metal with the auxiliary lip fixed, the seal member can be easily manufactured.

  When the sealing device of the present invention is used for the differential side of an automobile, it is particularly effective because thrust movement of the slinger remarkably occurs.

  According to the sealing device of the present invention, it is possible to suppress the life of the side lip from being reduced due to the movement of the slinger that is in sliding contact with the side lip.

It is sectional drawing which shows the principal part of the sealing device which concerns on one Embodiment of this invention. It is sectional drawing which shows the principal part of the conventional sealing device.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view showing a main part of a sealing device according to an embodiment of the present invention. The sealing device 1 is used on the differential side of an automobile, and is mounted in an annular space formed between a shaft 81 and a housing 82 that rotate relative to each other. This prevents foreign matter such as muddy water from entering the door.

The sealing device 1 includes a seal member 2 attached to the inner peripheral surface 82a of the housing 82, and a slinger 10 attached to the outer peripheral surface 81a of the shaft 81 on the outer side B from the seal member 2.
The slinger 10 is made of, for example, a metal such as stainless steel (for example, SUS material), and the cylindrical body 11 fitted to the outer peripheral surface 81a of the shaft 81 and the radially outer end from the axial inner end of the cylindrical body 11 And a torus 12 extending in the direction. The inner surface 12a of the torus 12 is a slidable contact surface with which a lip tip portion 64b of a side lip 64 described later is slidably contacted.

  The seal member 2 includes a cored bar part 3 and a seal main body 6 provided on the cored bar part 3. The core metal part 3 has a large-diameter cylindrical part 31, an annular part 32, and a small-diameter cylindrical part 33, and is formed in a substantially U-shaped cross section opened to the outer side B by these.

  Further, the cored bar portion 3 includes a first cored bar 4 having a substantially U-shaped cross section that opens to the outer side B, and a second cored bar 5 having a substantially L-shaped cross-section that is press-fitted into the first cored bar 4. And have. The first cored bar 4 is an annular member as a whole, and includes a first large-diameter cylindrical body 41, a first annular body 42, and a first small-diameter cylindrical body 43. Further, the second cored bar 5 is also an annular member as a whole, and includes a second cylindrical body 51 and a second annular body 52.

  In the first metal core 4, the first large-diameter cylindrical body 41 is formed to extend in the axial direction along the inner peripheral surface 82 a of the housing 82. A first annular body 42 that is bent inward in the radial direction and extends inward in the radial direction is formed at the axially inner end of the first large-diameter cylindrical body 41. A first small-diameter cylindrical body 43 that is bent to the outer side B and extends to the outer side B is formed at the inner peripheral end of the first annular body 42. The first small-diameter cylindrical body 43 has an annular projecting portion 43a that projects radially inward at the axially outer end portion thereof.

In the second metal core 5, a second annular body 52 that is bent inward in the radial direction and extends inward in the radial direction is formed at the inner end in the axial direction of the second cylindrical body 51. The length of the second cylindrical body 51 in the axial direction is shorter than that of the first large-diameter cylindrical body 41 of the first cored bar 4, and the radial length of the second annular body 52 is the first length. The core metal 4 is formed shorter than the first annular body 42.
The second cylindrical body 51 of the second metal core 5 is fitted and fixed to the inner peripheral surface of the first large-diameter cylindrical body 41 in the first metal core 4. The second annular body 52 of the second core metal 5 is fixed to the side surface of the first core metal 4 on the outer side B of the first annular body 42.

  With the above configuration, in the present embodiment, the first large-diameter cylindrical body 41 and the second cylindrical body 51 constitute the large-diameter cylindrical portion 31 of the cored bar portion 3, and the inner peripheral surface of the second cylindrical body 51. 51 a constitutes the inner peripheral surface of the large-diameter cylindrical portion 31. Further, the first annular body 42 and the second annular body 52 constitute the annular part 32 of the core metal part 3, and the side surface 52 a on the outer side B of the second annular body 52 is the core metal part 3. The side surface on the back side of the opening is configured. Further, the first small-diameter cylindrical body 43 constitutes the small-diameter cylindrical portion 33 of the cored bar portion 3 alone.

The seal body 6 is made of an elastic material such as synthetic rubber. The seal portion 61, the main lip 62 and the auxiliary lip 63 vulcanized and bonded to the first core metal 4, and the second core metal 5 are vulcanized. And a side lip 64 bonded thereto.
The seal part 61 is an annular member as a whole, and is formed in a substantially U-shaped cross section. The seal portion 61 includes an axial outer end surface and an outer peripheral surface of the first large-diameter cylindrical body 41, an inner side surface A of the first annular body 42, an inner peripheral surface of the first small-diameter cylindrical body 43, and a protruding portion 43a. And are fixed so as to cover each. A large-diameter cylindrical seal portion 61 a that covers the outer peripheral surface of the first large-diameter cylindrical body 41 in the seal portion 61 is fitted and fixed to the inner peripheral surface 82 a of the housing 82.

  A small-diameter cylindrical seal portion 61b that covers the inner peripheral surface of the first small-diameter cylindrical body 43 and the protruding portion 43a in the seal portion 61 extends from the end of the outer side B to the inner side A and radially inward, and has a shaft 81. An annular main lip 62 is formed in sliding contact with the outer peripheral surface 81a. A circumferential groove 62a is formed on the outer peripheral surface of the main lip 62, and an annular spring member 7 for pressing the main lip 62 from the outer peripheral side is attached to the circumferential groove 62a. The main lip 62 is pressed against the outer peripheral surface 81 a of the shaft 81 by being pressed by the spring member 7, and seals between the outer peripheral surface 81 a and the first cored bar 4.

  Further, the small-diameter cylindrical seal portion 61b of the seal portion 61 extends from the end on the outer side B to the outer side B and radially inward, and on the outer peripheral surface 81a of the shaft 81 on the outer side B from the main lip 62. An annular auxiliary lip 63 that is in sliding contact is formed. Thus, the auxiliary lip 63 prevents foreign matter that has passed through the sliding contact portion between the side lip 64 and the slinger 10 from the outer side B from entering the inner side A.

  The side lip 64 is made of an annular member, and is fixed to the axially outer end surface and inner peripheral surface 51 a of the second cylindrical body 51 and the radial outer end portion of the side surface 52 a of the second annular body 52. The side lip 64 has a lip base end portion 64a that extends outwardly B and radially inward, and a lip tip portion 64b that extends outwardly B and radially outward from the tip of the lip base end portion 64a. . The lip tip 64b is in sliding contact with the inner surface 12a of the torus 12 of the slinger 10, thereby preventing foreign matter from entering the inner side A from the outer side B.

  With the above configuration, the side lip 64, the slinger 10, the outer peripheral surface 81a of the shaft 81, the auxiliary lip 63, the outer peripheral surface 43b of the first small-diameter cylindrical body 43, and the side surface 52a of the second annular body 52. An annular space C is defined.

  As described above, according to the sealing device 1 of the present embodiment, the space C has a substantially cross-sectional shape opened to the outer side B in addition to the side lip 64, the slinger 10, the outer peripheral surface 81a of the shaft 81, and the auxiliary lip 63. A section is also formed by the outer peripheral surface 43b of the small-diameter cylindrical portion 33 in the letter-shaped cored bar portion 3 and the side surface 52a on the back side of the opening. Thereby, since the volume of the space part C can be enlarged in the axial direction as compared with the volume of the conventional space part 123 (see FIG. 2), the slinger 10 is positioned at the solid line position in FIG. Even if the volume of the space C changes due to the thrust movement that reciprocates in the axial direction between the two-dot chain line position, the rate of change can be reduced. As a result, the positive pressure value and the negative pressure value in the space C can be reduced, and wear of the sliding contact portion of the side lip 64 with the slinger 10 can be suppressed. Therefore, it is possible to suppress the life of the side lip 64 from being reduced due to the side lip 64 being in sliding contact with the slinger 10. In particular, when the sealing device 1 is used on the differential side of an automobile, the above-described thrust movement of the slinger 10 occurs remarkably, which is effective.

  Further, the main lip 62 and the auxiliary lip 63 are fixed to the first small-diameter cylindrical body 43 of the first core metal 4, and the side lip 64 is fixed to the second annular body 52 of the second core metal 5. The sealing member 2 can be easily manufactured by fitting and fixing the second core metal 5 with the side lip 64 fixed to the first core metal 4 to which the 62 and the auxiliary lip 63 are fixed.

Note that the present invention is not limited to the above-described embodiment, and can be implemented with appropriate modifications. For example, the sealing device 1 of the present invention may be applied to a shaft seal portion of various devices other than the differential side of an automobile.
Moreover, in the said embodiment, although only the side surface 52a of the 2nd annular body 52 is used as a side surface of the opening back side of the metal core part 3 which divides and forms the space part C, the 2nd annular body 52 is used. The side surface 52a of the second annular body 52 and the side surface of the outer side B of the first annular body 42 may be used, or only the side surface of the outer side B of the first annular body 42 may be used. May be used.

  1: sealing device, 2: sealing member, 3: cored bar part, 4: first cored bar, 5: second cored bar, 10: slinger, 12a: sliding contact surface, 31: large diameter cylindrical part, 33: small diameter Cylindrical portion, 41: first large-diameter cylindrical body, 42: first annular body, 43: first small-diameter cylindrical body, 43b: outer peripheral surface (outer peripheral surface of the small-diameter cylindrical portion), 51: second cylindrical body, 51a: Inner peripheral surface (inner peripheral surface of large-diameter cylindrical portion), 52: second annular body, 52a: side surface (side surface on the opening back side of the core metal portion), 62: main lip, 63: auxiliary lip, 64: side Lip, 81: shaft, 81a: outer peripheral surface, 82: housing, A: inside, B: outside, C: space

Claims (3)

In an annular space formed between a shaft and a housing that rotate relative to each other, a seal member that is mounted on the housing and the seal to prevent foreign matter from entering from the outside to the inside of the housing A slinger having a sliding contact surface extending in a radial direction on the outer side of the member and attached to the shaft,
The sealing member is
A cored bar portion having a substantially U-shaped cross section that is open to the outside;
A main lip fixed to the axially outer end portion of the small-diameter cylindrical portion on the radially inner side of the cored bar portion and in sliding contact with the outer peripheral surface of the shaft;
An auxiliary lip that is fixed to the outer end portion in the axial direction of the small-diameter cylindrical portion, and that is in sliding contact with the outer peripheral surface of the shaft on the outer side of the main lip;
A side lip that is fixed to the inner peripheral surface of the large-diameter cylindrical portion on the radially outer side of the core metal portion and the side surface on the back side of the opening of the core metal portion and slidably contacts the sliding contact surface of the slinger,
A sealing device, wherein a space portion is defined by the side lip, the slinger, the outer peripheral surface of the shaft, the auxiliary lip, the outer peripheral surface of the small-diameter cylindrical portion, and the side surface on the back side of the opening. The core metal part is
A first large-diameter cylindrical body extending in an axial direction along an inner peripheral surface of the housing; a first annular body extending radially inward from an axial inner end of the first large-diameter cylindrical body; and the first A first cored bar having a first small-diameter cylindrical body extending axially outward from an inner peripheral end of the torus, wherein the first small-diameter cylindrical body constitutes the small-diameter cylindrical part;
A second cylindrical body fitted and fixed to the inner peripheral surface of the first large-diameter cylindrical body, and extending radially inward from an axially inner end of the second cylindrical body, and the first annular body A second metal core having a second annular ring fixed to the outer side surface,
The inner circumferential surface of the second cylindrical body constitutes an inner circumferential surface of the large-diameter cylindrical portion, and the outer side surface of the second annular body constitutes a side surface on the back side of the opening. The sealing device according to 1.   The sealing device according to claim 1, wherein the sealing device is used for a differential side of an automobile.

Images