JP2010112481A - Oil seal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress occurrence of inconvenience such as an improper incorporating position by reducing a fitting load of a second metal ring with respect to an oil seal body, in regard to an oil seal of an assembly structure wherein the second metal ring is fit on an inner circumference face of an inner face attaching part from one axial direction with a predetermined fitting allowance in an inner circumference side of a metal ring of the oil seal body. <P>SOLUTION: The oil seal has the oil seal body wherein a seal lip and the inner face attaching part attached to an inner circumference face of the metal ring are formed by a rubbery elastic body attached to the metal ring, and the second metal ring fit on the inner circumference face of the inner face attaching part from one axial direction with the predetermined allowance in the inner circumference side of the metal ring. Protrusions are plurally provided on one axial end position in the inner face attaching part, and a structure is provided wherein the protrusions are respectively moved to circumferential both sides when the second metal ring is fit with the predetermined allowance from one axial direction on inner circumference faces of the plurality of protrusions. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an oil seal which is a kind of sealing device, and more particularly to an oil seal having an assembly structure having an oil seal main body and a second metal ring fitted to the oil seal main body.

Conventionally, as shown in FIG. 3, an oil seal in which a seal lip 55 and an inner surface attaching portion 56 attached to the inner peripheral surface of the metal ring 53 are formed by a rubber-like elastic body 54 attached to the metal ring 53. An assembly structure having a main body 52 and a second metal ring 57 that is fitted to the inner circumferential surface of the inner surface adherence 56 with a predetermined fitting margin from one side in the axial direction on the inner circumferential side of the metal ring 53. An oil seal 51 is known (see Patent Document 1).
Japanese Patent Laying-Open No. 2006-233992 (FIG. 6)

  However, according to this prior art, the second metal ring 57 is attached to the inner peripheral surface of the cylindrical inner surface coated portion 56 formed with a uniform thickness over the entire circumference with a predetermined allowance from one axial direction. Because of the fitting structure, there is a possibility that inconveniences such as an inappropriate mounting position due to a large fitting load or an inclination of the second seal 58 may occur in the step of fitting the second metal ring 57.

In addition, a plurality of lightening portions 59 are provided on the circumference at the end position on the inner side of the inner surface adherend portion 56, and a relatively convex portion 60 is provided between the lightening portions 59, 59 adjacent to each other on the circumference. However, the inner diameter dimension d ₁ of the convex portion 60 is larger than the inner diameter dimension d ₂ of the inner surface adherend portion 56 and the outer dimension d ₃ of the second metal ring 57 fitted to the inner surface adherend portion 56. It is set large. Therefore, the protrusion 60 does not interfere with the second metal ring 57 at the time of fitting, and is distinguished from the “projection” of the present invention in this respect.

  In view of the above, the present invention fits the second metal ring with a predetermined fitting allowance from one side in the axial direction to the inner peripheral surface of the metal ring of the oil seal main body and on the inner peripheral surface of the inner surface adherent portion. To provide an oil seal that can reduce the fitting load of the second metal ring with respect to the oil seal main body and suppress the occurrence of inconvenience such as improper assembly position in the oil seal of the assembly structure. Objective.

  In order to achieve the above object, an oil seal of the present invention is an oil seal in which a seal lip is formed by a rubber-like elastic body attached to a metal ring, and an inner surface attached portion is attached to the inner peripheral surface of the metal ring. In the oil seal having a main body and a second metal ring which is fitted on the inner circumferential surface of the inner surface of the metal ring and is fitted to the inner circumferential surface of the inner surface adherent portion from one axial direction with a predetermined fitting margin, the inner surface When a plurality of protrusions are provided on the circumference in one axial position of the adherend, and the second metal ring is fitted to the inner peripheral surface of the plurality of protrusions with a predetermined fitting allowance from one of the axial directions. Each of the protrusions is provided with a structure for escaping to both sides in the circumferential direction by the fitting allowance.

  In the oil seal of the present invention having the above-described configuration, a plurality of protrusions are provided on the circumferential surface at one end position in the axial direction, and a predetermined fit is provided on the inner peripheral surface of the plurality of protrusions from one axial direction. When the second metal ring is fitted with an allowance, the protrusions are elastically deformed by the fit allowance and can escape to both sides in the circumferential direction. Therefore, since the fitting margin of the second metal ring with respect to the oil seal main body is substantially absorbed by this, the fitting load is reduced.

  As described above, according to the present invention, a plurality of protrusions are provided on the circumferential surface at one end position in the axial direction of the inner surface adherent portion, and a predetermined fitting allowance is provided on the inner peripheral surface of the plurality of protrusions from one axial direction. When the second metal ring is fitted, the projections are elastically deformed by the fitting allowance and can escape to both sides in the circumferential direction. Accordingly, since the fitting allowance of the second metal ring to the oil seal main body is substantially absorbed by this, the fitting load of the second metal ring to the oil seal main body can be reduced, and there is a disadvantage such as improper installation position. Generation | occurrence | production can be suppressed.

  The present invention includes the following embodiments.

(1) There is an assembly-type seal with a second lip as an oil seal shape that has a function to remove foreign matter in oil. However, in the seal assembly process, an improper assembly position due to a large fitting load and a seal inclination occur. There is a case.
(2) Therefore, a rubber protrusion having an equal distribution is provided on the inner peripheral portion of the seal so as to hold the second lip portion. The size of the protrusion is preferably as small as possible, but is set so that the second metal ring is held at 10 or more intervals so that it can be held concentrically.
(3) According to the above configuration, the rubber compressed by the fitting of the second lip portion can be released to both sides by holding by the equally spaced projections, and the fitting load can be suppressed. As a result, the assembly position can be stabilized. Also, the seal inclination can be suppressed.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a cross section of a main part of an oil seal 1 according to an embodiment of the present invention. FIG. 2 is a side view of an essential part of an oil seal main body 11 which is one component of the oil seal 1, and shows a view in the direction of arrow A in FIG. The right side of FIG. 1 is the aircraft inner side, and the left side is the atmosphere side. The oil seal 1 according to this embodiment is mounted on the inner periphery of the shaft hole of the housing 41 and is slidably in close contact with the peripheral surface of the shaft 43 inserted through the shaft hole. A combination with the two lip members 31 is used. The second lip member 31 is fitted to the oil seal main body 11 from one side in the axial direction (right side in the figure, the inside of the machine, hereinafter also referred to as “machine inside”).

  The oil seal main body 11 has a metal ring 12 fitted to the shaft hole inner peripheral surface 42 of the housing 41, and the rubber-like elastic body 13 attached (vulcanized and bonded) to the metal ring 12 The seal lip 14 slidably in close contact with the peripheral surface of the shaft 43, the dust strip 15, the end face attaching portion 16 attached to the end face portion of the metal ring 12, and the outer peripheral portion of the metal ring 12. In addition, an outer peripheral seal portion 17 that seals between the metal ring 12 and the housing 41 and an inner surface attached portion 18 that is attached to the inner peripheral portion of the metal ring 12 are integrally formed.

  The metal ring 12 has a cylindrical portion 12a fitted to the inner peripheral surface 42 of the shaft hole of the housing 41. The other axial direction of the cylindrical portion 12a (left side in the figure, atmosphere side, hereinafter “atmosphere”). A flange portion 12b is integrally formed at an end portion of the flange portion 12b inward in the radial direction, and a seal lip 14 is disposed from the inner peripheral end portion of the flange portion 12b toward the inside of the machine. Therefore, the seal lip 14 is disposed on the inner peripheral side of the cylindrical portion 12 a of the metal ring 12. A garter spring 19 is fitted on the outer periphery of the seal lip 14.

  The said end surface coating | coated part 16 is adhered to the atmospheric | air-end side end surface of the flange part 12b of the metal ring 12, and has coat | covered this end surface. The outer peripheral seal portion 17 is attached to the outer peripheral surface of the cylindrical portion 12a of the metal ring 12 so as to cover the outer peripheral surface, and is in close contact with the inner peripheral surface 42 of the shaft hole of the housing 41 when mounted. 41 is sealed. The inner surface adherent portion 18 is attached to the inner peripheral surface of the cylindrical portion 12a of the metal ring 12 and covers the inner peripheral surface.

  Further, a plurality of protrusions 20 are provided on the circumference at the end position on the inner surface side of the inner surface adherent portion 18, and the second inner surface of the plurality of protrusions 20 has a predetermined fitting allowance from the inner side of the machine. When the second lip member 31 having the metal ring 32 is fitted, the projections 20 are elastically deformed by the fitting allowance and escape to both sides in the circumferential direction. Each of the protrusions 20 is formed so as to rise radially inward from the inner peripheral surface of the cylindrical portion 12 a of the metal ring 12, and the inner diameter dimension thereof is set to be equal to the inner diameter dimension of the inner surface adherent portion 18. Yes. The protrusion 20 has a predetermined cross-sectional shape (cross-sectional shape perpendicular to the axis), and has a predetermined axial length while maintaining this cross-sectional shape. The number of protrusions 20 formed is not particularly limited, but it is desirable that the number of protrusions 20 be 10 or more in order to easily hold the second lip member 31 having the second metal ring 32 concentrically. A recess 21 is provided between the protrusions 20 adjacent to each other on the circumference. The recess 21 also has a predetermined cross-sectional shape (cross-sectional shape perpendicular to the axis), and has a predetermined axial length while maintaining this cross-sectional shape.

  On the other hand, the second lip member 31 is fitted to the inner peripheral side of the cylindrical portion 12a of the metal ring 12, and as described above, the inner surface is attached to the inner peripheral surface of the cylindrical portion 12a of the metal ring 12. Since the portion 18 is adhered and the projection 20 is integrally formed, the second lip member 31 is fitted to the inner surface of the inner surface adhered portion 18 and the projection 20.

  The second lip member 31 has a second metal ring 32 fitted to the inner peripheral surface of the inner surface adherend portion 18 and the protrusion 20 on the inner peripheral side of the cylindrical portion 12 a of the metal ring 12. A second seal lip 34 slidably in close contact with the peripheral surface of the shaft 43 by a rubber-like elastic body 33 adhered (vulcanized and bonded) to the second metal ring 32, and a second metal ring An end surface attaching portion 35 attached to the 32 end surface portions is integrally formed.

  The second metal ring 32 has, as its constituent elements, a cylindrical portion 32a that is fitted to the inner peripheral surface of the inner surface adherent portion 18 and the protrusion 20 with a predetermined fitting allowance, and this cylindrical portion 32a. The flange portion 32b is integrally formed at the inner end of the machine toward the inner side in the radial direction. Since the flange portion 32 b is disposed on the inner side of the lip end 14 a of the seal lip 14, the second seal lip 34 provided on the inner peripheral end portion is provided on the peripheral surface of the shaft 43 on the inner side of the seal lip 14. It will be closely slidable.

  An inclined chamfered portion 32c is provided on the outer peripheral surface of the distal end portion of the cylindrical portion 32a in order to facilitate the fitting operation. In addition, an inclined surface-shaped step 32d is provided at substantially the center in the axial direction of the cylindrical portion 32a, and the cylindrical portion 32a is divided into a large-diameter portion 32e on the atmosphere side and a small-diameter portion 32f on the inside of the machine with this step portion 32d as a boundary. It is divided into. The outer diameter dimension of the large diameter portion 32e is set larger than the inner diameter dimension of the inner surface adherent portion 18 and the protrusion 20, whereas the outer diameter dimension of the small diameter portion 32f is equal to the inner diameter dimension of the inner surface adherent portion 18 and the protrusion 20. They are set to be the same or slightly smaller than the inner diameter dimensions of the inner surface adherent portion 18 and the protrusion 20. Therefore, the second metal ring 32 is fitted so as to bite into the inner peripheral surface of the inner surface adherend portion 18 and the protrusion 20 with the cylindrical surface between the chamfered portion 32c and the stepped portion 32d in the large diameter portion 32e of the cylindrical portion 32a. ing.

  In the oil seal 1 having the above-described configuration, a plurality of protrusions 20 are provided on the inner edge of the inner surface adherent portion 18 on the inner side, and a predetermined fitting allowance is provided on the inner peripheral surface of the plurality of protrusions 20 from the inner side. When the second lip member 31 having the second metal ring 32 is fitted, the projections 20 are elastically deformed by the fitting allowance and can escape to both sides in the circumferential direction. Therefore, since the fitting allowance of the second metal ring 32 with respect to the oil seal body 11 is substantially absorbed by this, the fitting load of the second metal ring 32 with respect to the oil seal body 11 can be reduced, and therefore the installation position is inappropriate. Alternatively, it is possible to suppress the occurrence of inconvenience such as the inclination of the seal (second seal lip 34).

  Incidentally, as described above, the inner surface coated portion 18 is deposited on the inner circumferential surface of the cylindrical portion 12a of the metal ring 12 to cover the inner circumferential surface. A plurality of protrusions 20 are provided on the circumference of the end portion 18 on the machine inner side of the portion 18, and the inner diameter dimension of the protrusion 20 is set to be equal to the inner diameter dimension of the inner surface adherent portion 18. Therefore, depending on the way of view, a plurality of recesses 21 are provided on the circumference of the inner surface covering portion 18 instead of the protrusions 20 at the end of the machine, and as a result, the protrusions 20 are formed between the recesses 21 and 21 adjacent to each other. In this case, the description of claim 1 is as follows.

  That is, “on the inner peripheral side of the metal ring, the oil seal main body formed with the rubber lip elastic member attached to the metal ring and the seal lip, and the inner surface attached portion attached to the inner peripheral surface of the metal ring; An oil seal having a second metal ring fitted to the inner circumferential surface of the inner surface adherent part from one axial direction with a predetermined allowance, and one end position of the inner face adherent part in the axial direction A plurality of recesses are provided on the circumference, and projections are provided between the recesses adjacent to each other. When the second metal ring is fitted to the inner circumferential surface of the projection with a predetermined fitting margin from one axial direction, the projection Is provided with a structure that escapes to both sides in the circumferential direction by the fitting allowance. "

  Moreover, in the said Example, although the 2nd metal ring 32 has the 2nd seal lip 34 in the inner peripheral edge part, and comprises the 2nd lip member 31, the 2nd seal lip 34 may be abbreviate | omitted. That is, the second metal ring 32 may be a single component. In this case, the second metal ring 32 is used as a protective ring for preventing foreign matter from colliding with the seal lip 14, or the mist-like sealing target oil adhering to the surface of the second metal ring 32 is focused to surround the peripheral surface of the shaft 43. It is used as oil droplets that are dropped on the top to supply lubricating oil to the seal lip sliding portion 14b.

It is principal part sectional drawing of the oil seal which concerns on the Example of this invention, Comprising: BB sectional drawing in FIG. It is a principal part side view of the oil seal main body which is the component of the oil seal, Comprising: A direction arrow directional view in FIG. Cross section of the main part of the oil seal according to the conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Oil seal 11 Oil seal main body 12 Metal ring 12a, 32a Tubular part 12b, 32b Flange part 13 Rubber-like elastic body 14 Seal lip 14a Lip end 14b Lip sliding part 15 Dustrip 16 End face covering part 17 Outer peripheral seal part 18 Inner surface adherence portion 19 Garter spring 20 Protrusion 21 Recess 31 Second lip member 32 Second metal ring 32c Chamfered portion 32d Stepped portion 32e Large diameter portion 32f Small diameter portion 41 Housing 42 Shaft hole inner peripheral surface 43 Axis

Claims (1)

An oil seal body having a seal lip formed by a rubber-like elastic body attached to the metal ring, and an inner surface attached portion attached to the inner peripheral surface of the metal ring; In the oil seal having the second metal ring fitted to the inner peripheral surface of the inner surface adherent portion with a predetermined fitting margin from one axial direction,
A plurality of protrusions are provided on the circumference of one end portion in the axial direction of the inner surface adherent portion, and the second metal ring is fitted to the inner peripheral surface of the plurality of protrusions from the one axial direction with a predetermined fitting allowance. The oil seal is characterized in that the protrusion is sometimes provided to escape to both sides in the circumferential direction by the fitting allowance.

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