JP2010071377A - Sealing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing device superior in follow-up performance to eccentricity of a rotary body, without impairing stability of a sealing state of a seal lip even to thrust displacement of the rotary body. <P>SOLUTION: This sealing device is interposed between a housing and the rotary body of its inner periphery, and includes a support 1 having a plurality of flanges 11b and 12b tightly fitted to the housing side and juxtaposed in the axial direction, and a sealing device body 2. The sealing device body 2 comprises: a support object ring 21 displaceably supported in the axial direction and the radial direction via elastic bodies 3 and 3 comprising a porous elastic body having a continuous pore between the plurality of flanges 11b and 12b; and a seal lip 22 integrally arranged in this support object ring 21 and slidably brought into close contact with the rotary body. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a sealing device, and more particularly to a device suitable for sealing at a site where relative eccentricity between a housing and a shaft and relative axial displacement are large.

  For example, as a sealing device used as a sealing means between an extension housing and a rotating shaft of an automobile, for example, a device as shown in FIG. 4 or FIG. 5 is conventionally known.

  Among these, the sealing device shown in FIG. 4 includes an outer peripheral seal portion 102 that is press-fitted into the inner peripheral surface of the housing, an oil lip 103 that is slidably in contact with the outer peripheral surface of the rotary shaft, and a lip 104 for dust. The side lip 105 for dust is provided on the metal reinforcing ring 101 integrally with a rubber material or a synthetic resin material having rubber-like elasticity.

  In this type of sealing device, it is effective to reduce the thickness of the oil lip 103 in order to ensure the followability to the eccentricity of the rotating shaft, but in this case, the rigidity of the oil lip 103 decreases. Therefore, there is a concern that the contact state between the outer peripheral surface of the rotating shaft and the oil lip 103 becomes unstable with respect to the axial displacement.

Further, the sealing device shown in FIG. 5 includes a metal outer ring 201 press-fitted into the inner peripheral surface of the housing, a metal inner ring 202 integrally incorporated therein, and a rubber material or It is integrally formed of a synthetic resin material having rubber-like elasticity, and includes a bellows portion 203 and an oil lip 204 that is continuously provided on the inner diameter side of the bellows portion 203 and slidably comes into contact with the outer peripheral surface of the rotating shaft ( For example, see Patent Document 1).
JP-A-9-112706

  However, in this sealing device as well, although the excellent followability of the oil lip 204 is ensured by the bellows 203, the contact state between the outer peripheral surface of the rotating shaft and the oil lip 204 is unstable with respect to axial displacement. There is concern about becoming.

  The present invention has been made in view of the above points, and its technical problem is that it has excellent followability with respect to shaft eccentricity, and the stability of the seal lip in close contact with the thrust displacement of the shaft. An object of the present invention is to provide a sealing device that does not damage the surface.

  As a means for effectively solving the above technical problem, a sealing device according to the invention of claim 1 is a sealing device interposed between a housing and a rotating body on the inner periphery thereof, and the housing A support body having a plurality of flanges closely fitted on the side and arranged in the axial direction; and a sealing device body, wherein the sealing device body is axially and radially displaced via an elastic body between the plurality of flanges. It comprises a supported ring that is supported, and a seal lip that is provided integrally with the supported ring and that is slidably in contact with the rotating body.

  In a sealing device according to a second aspect of the present invention, the elastic body according to the first aspect comprises a porous elastic body having continuous pores. Examples of the porous elastic body having continuous pores herein include fiber aggregates such as fabrics, felts, and cotton-like bodies, and foamed resins (sponges) having open cells.

  According to a third aspect of the present invention, there is provided the sealing device according to the first aspect, wherein the supporting member and the supported ring are provided with mutual rotation preventing means.

  According to the sealing device of the first aspect of the present invention, the supported ring of the sealing device body is supported between the flanges of the support body that is tightly fitted to the housing side so as to be axially and radially displaceable via the elastic body. Therefore, the sealing device main body can follow the eccentricity and axial displacement of the rotating body with respect to the housing, and the stability of the sealing lip in the sealing device main body is ensured.

  According to the sealing device of the second aspect of the present invention, the elastic body interposed between the flange of the support body and the supported ring of the main body of the sealing apparatus is made of a porous elastic body having continuous pores. The followability of the sealing device main body against the eccentricity and axial displacement of the body can be further improved.

  According to the sealing device of the third aspect of the present invention, the rotation of the sealing device body due to the sliding torque of the seal lip that slides with the rotating body is prevented.

  Hereinafter, preferred embodiments of a sealing device according to the present invention will be described with reference to the drawings. First, FIG. 1 is a half sectional view showing a first embodiment of a sealing device according to the present invention by cutting along a plane passing through its axis.

  The sealing device shown in FIG. 1 includes a support body 1 that is tightly fitted to an inner peripheral surface of a housing (not shown), and a sealing device body 2 that is supported on the support body 1 via an elastic body 3.

  The support 1 includes a metal outer ring 11 and an inner ring 12 that are integrally fitted to each other, and an outer peripheral seal portion 13 that is formed of a rubber material or a rubber-like elastic material and is provided integrally with the outer ring 11. And side lip 14.

  Specifically, the outer ring 11 in the support body 1 has an outer diameter cylindrical portion 11 a and a flange 11 b that is bent from one end to the inner diameter side, and the inner ring 12 is an inner diameter of the outer diameter cylindrical portion 11 a of the outer ring 11. An outer diameter cylindrical portion 12a fitted to the peripheral surface, a flange 12b bent from one end of the outer diameter cylindrical portion 12a to the inner diameter side and aligned with the flange 11b at a predetermined interval in the axial direction, and an inner diameter of the flange 12b It has an inner diameter cylindrical portion 12c that is folded back from the end concentrically with the outer diameter cylindrical portion 12a.

  The outer peripheral seal portion 13 in the support 1 is in close contact with the inner peripheral surface of the housing in an appropriate compressed state, and is integrated with the outer peripheral surface of the outer diameter cylindrical portion 11a of the outer ring 11 by vulcanization adhesion or the like. ing.

  The side lip 14 in the support body 1 has a conical cylindrical shape with a large diameter at the tip side facing the outside of the machine, and the tip is closely slidably attached to a slinger (not shown) attached to the rotating shaft side described later, for example. The root 14 a is integrated with the inner diameter portion of the flange 11 b of the outer ring 11 by vulcanization adhesion or the like, and is continuous with the outer peripheral seal portion 13.

  The sealing device main body 2 includes a metal supported ring 21 arranged in a loose fit between the flange 11b of the outer ring 11 and the flange 12b of the inner ring 12 in the support 1, and a rubber material or a rubber-like elastic material. The oil lip 22, the dust lip 23, and the outer peripheral lip 24 integrally formed on the supported ring 21, and a garter spring 25 mounted on the outer periphery of the oil lip 22. The oil lip 22 corresponds to the seal lip described in claim 1.

  Specifically, the supported ring 21 in the sealing device main body 2 has a washer shape in which the outer diameter is appropriately smaller than the inner diameter of the outer diameter cylindrical portion 11a of the outer ring 11 in the support 1, and the outer diameter portion 21a. However, the support 1 is sandwiched between the flange 11b of the outer ring 11 and the flange 12b of the inner ring 12 via a pair of elastic bodies 3 and 3 so as to be axially and radially displaceable.

  The oil lip 22 in the sealing device main body 2 faces the machine inside where a bearing or the like (not shown) exists, that is, faces the side lip 14 in the support 1, and the root of the oil lip 22 of the supported ring 21. It is integrated with the inner diameter portion 21b by vulcanization adhesion or the like, and the lip edge 22a at the inner diameter portion of the tip is slidable with an appropriate tightening margin on the outer peripheral surface of a rotating shaft (not shown) inserted through the inner periphery of the housing. By being in close contact with each other, leakage of lubricating oil inside the machine to the outside of the machine is prevented. The rotating shaft corresponds to the rotating body described in claim 1.

  Further, on the inner peripheral surface of the lip edge 22a on the outside of the machine, a spiral groove (or a spiral ridge) 22b that exhibits a screw pump action toward the inside of the machine by the rotation of the rotary shaft is formed. The sub-edge 22c for stabilizing the posture of the oil lip 22 is formed continuously in the circumferential direction.

  The anti-dust lip 23 in the sealing device main body 2 faces away from the anti-lip lip 22, that is, the outside of the machine, and the root of the anti-dust lip 23 is continuous with the base of the anti-lip lip 22 to the inner diameter portion 21 b of the supported ring 21. It is integrated by vulcanization adhesion or the like, and the tip inner diameter portion is slidably brought into close contact with the outer peripheral surface of the rotating shaft, thereby preventing dust and the like from entering the inside of the machine.

  The outer peripheral lip 24 in the sealing device main body 2 has a conical cylindrical shape with a large diameter at the tip side facing the inside of the machine. The root of the outer peripheral lip 24 is supported at the outer peripheral position of the base of the oil lip 22. The tip outer diameter portion chamfered in an R-surface shape is in close contact with the inner peripheral surface of the inner diameter cylindrical portion 12c of the inner ring 12 in the support 1 with an appropriate margin. Yes. For this reason, it has the effect | action which elastically supports the sealing device main body 2 with respect to the support body 1 to radial direction.

  The garter spring 25 in the sealing device main body 2 is for compensating the tight force of the oil lip 22 with respect to the rotating shaft, and is formed by connecting an elongated metal coil spring in an annular shape.

  The elastic bodies 3 interposed between the opposing surfaces of the flange 11b of the outer ring 11 and the flange 12b of the inner ring 12 and the supported ring 21 of the sealing device body 2 in the support body 1 are porous elastic bodies having continuous pores, For example, a fiber assembly such as fabric, cotton, felt or the like, or a foamed resin (sponge) having open cells formed into an annular shape, and can be flexibly deformed. The elastic body 3 may be bonded to one of the flanges 11 b and 12 b and the supported ring 21.

  According to the sealing device of the first embodiment configured as described above, the supported ring 21 of the sealing device body 2 is between the flange 11b of the outer ring 11 and the flange 12b of the inner ring 12 in the support 1. Since the shaft is sandwiched between the pair of elastic bodies 3 and 3 so as to be axially and radially displaceable, for example, when the rotating shaft is eccentric with respect to the housing, the oil lip 22 and the dust against the outer peripheral surface of the rotating shaft. The sealing device main body 2 to which the lip 23 for use is in close contact with the support 1 is within the range of the radial gap G between the inner diameter of the outer diameter cylindrical portion 11 a of the outer ring 11 and the outer diameter of the supported ring 21. Thus, the displacement can be followed in the radial direction. For this reason, the intimate contact between the oil lip 22 and the dust lip 23 with respect to the outer peripheral surface of the rotating shaft is impaired, or the surface pressure of the oil lip 22 and the dust lip 23 increases abnormally in a part of the circumferential direction. Can be effectively prevented.

  When the sealing device body 2 is decentered with respect to the support 1, the outer peripheral lip 24 is subjected to bending deformation in the radial direction, and the distal end outer diameter portion is within the inner diameter cylindrical portion 12 c of the inner ring 12 in the support 1. Since the state of close contact with the peripheral surface is maintained, dust that has entered the elastic body 3 made of a porous elastic body from the sliding portion of the side lip 14 of the support body 1 further enters the inside of the machine from the elastic body 3. Can be prevented.

  Further, when the rotating shaft is displaced in the axial direction with respect to the housing, for example, the sealing device body 2 is supported by the supported ring 21 by the frictional force between the outer peripheral surface of the rotating shaft and the oil lip 22 and the dust lip 23. And the flanges 11b, 12b on both sides in the axial direction are displaced along the axial direction with the flexible deformation of the elastic body 3, so that the oil lip 22 and the dust lip 23 are turned over. It is possible to effectively prevent the posture from becoming unstable. Moreover, since the axial displacement of the sealing device main body 2 is limited within the compression limit range of the elastic body 3, the axial followability is provided by the bellows 203 as in the conventional structure shown in FIG. Compared to the given one, the sealing position by the oil lip 22 and the dust lip 23 can be stabilized.

  At this time, the outer peripheral lip 24 slides in the axial direction with the inner peripheral surface of the inner diameter cylindrical portion 12c of the inner ring 12 in the support 1, but the outer peripheral lip 24 has an R-shaped outer peripheral portion. Since it is chamfered, even if dust is present on the elastic body 3 side, the action of scraping out this dust to the inside of the machine does not occur.

  Here, the elastic body 3 made of a porous elastic body has a small repulsive force against compression, that is, a small fixing force with respect to the supported ring 21 (sealing device body 2). There is a concern that the sealing device body 2 may rotate due to the sliding torque. FIG. 2 is a half sectional view showing a second embodiment provided with a detent means for preventing the rotation of the sealing device main body 2 by cutting along a plane passing through its axis, and FIG. 3 is a sectional view taken along line III-III in FIG.

  In the second embodiment, the difference from the first embodiment described above is that a detent means for preventing relative rotation is formed on the outer ring 11 of the support 1 and the supported ring 21 of the sealing device body 2. It is in. The other parts are basically the same as in FIG.

  Specifically, a plurality of engagement protrusions 11c are circular on the inner peripheral surface of the outer diameter cylindrical portion 11a of the outer ring 11 of the support 1 that is located between the flange 11b and the flange 12b of the inner ring 12. They are formed at a predetermined phase interval in the circumferential direction. The engaging protrusion 11c can be formed by being recessed from the outer diameter side by embossing or the like.

  On the other hand, a plurality of engagement notches 21c are formed in the outer diameter portion 21a of the supported ring 21 in the sealing device main body 2 at a phase interval corresponding to the above-described engagement protrusions 11c. They are engaged with each other in the circumferential direction in a loosely fitted state.

  According to the sealing device of the second embodiment configured as described above, in addition to the effects of the first embodiment described above, the oil lip 22 and the dust lip 23 that slide with the outer peripheral surface of the rotating shaft. It is possible to reliably prevent the sealing device body 2 from rotating relative to the support 1 by the sliding torque of the engagement protrusion 11c and the engagement notch 21c.

  In addition to the one shown in FIGS. 2 and 3, for example, the flange 11 b of the outer ring 11, the flange 12 b of the inner ring 12, and the outer diameter portion 21 a of the supported ring 21 are respectively embossed or the like. A configuration in which the supported ring 21 is prevented from rotating through the elastic bodies 3 and 3 by forming axial protrusions and biting them into the elastic bodies 3 and 3 can be considered.

It is a half sectional view which cuts and shows the 1st form of the sealing device concerning the present invention by the plane which passes along the axis. It is a half sectional view which cuts and shows the 2nd form of the sealing device concerning the present invention by the plane which passes along the axis. FIG. 3 is a sectional view taken along line III-III in FIG. 2. It is a semi-sectional view which shows an example of a sealing device according to the prior art by cutting along a plane passing through its axis. FIG. 10 is a half cross-sectional view showing another example of a sealing device according to the prior art, cut along a plane passing through its axis.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Support body 11b, 12b Flange 11c Engagement protrusion (rotation prevention means)
2 Sealing device body 21 Supported ring 21c Engagement notch (rotation prevention means)
22 Oil lip (seal lip)
23 Anti-dust lip 24 Outer lip 3 Elastic body

Claims (3)

  A sealing device interposed between a housing and a rotating body on the inner periphery thereof, comprising: a support body having a plurality of flanges closely fitted on the housing side and arranged in the axial direction; and a sealing device main body, The sealing device main body is supported between the plurality of flanges via an elastic body so as to be axially and radially displaceable, and is provided integrally with the supported ring and slides on the rotating body. A sealing device comprising a seal lip that is movably brought into close contact.   The sealing device according to claim 1, wherein the elastic body is a porous elastic body having continuous pores.   The sealing device according to claim 1, wherein the supporting member and the supported ring are provided with a rotation preventing means for each other.

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