JP3196643U - Sealing device - Google Patents

Abstract

By optimizing the position of the front end of a first backup ring member, it is possible to effectively prevent damage to the first seal ring member and to stabilize the first seal ring member from the back side for a long period of time. A sealing device capable of being supported is provided. A sealing device includes a first seal ring member made of an elastomer having a first cylindrical portion, a first seal lip portion, and a first curved portion, and a back side of the first seal ring member. A first backup ring made of metal having a second cylindrical portion 21 positioned and extending in close contact with the back surface of the first cylindrical portion 11 and a second curved portion 22 curved corresponding to the back surface of the first curved portion 12. The second bending portion 22 has a tip portion 22a that extends in the direction of decreasing the inner diameter with respect to the innermost diameter position on the back surface of the first bending portion 12. [Selection] Figure 2

Description

  The present invention seals between a housing having a shaft hole and a rotating shaft fitted in the shaft hole of the housing, thereby preventing leakage of the sealed fluid accommodated in the sealed space to the atmosphere side. The present invention relates to a sealing device for preventing.

  As a conventional sealing device, for example, a sealing ring member that is used to seal around the rotating shaft of a compressor in an air conditioner of an automobile and the like is slidably contacted with the outer peripheral surface of the rotating shaft, and the sealed state of the sealed space is set. Maintaining sealing devices are known. The seal ring member that constitutes such a seal device is made of an elastomer material such as rubber having excellent sealing performance, and is configured such that the seal lip portion at the tip of the seal ring member and the outer peripheral surface of the rotating shaft are always in contact with each other. The refrigerant gas or lubricating oil, which is a sealed fluid filled in the space inside the compressor to be sealed, is sealed to make the space inside the sealed space, and the sealed fluid leaks from the space inside the device to the outside. Is preventing.

  As shown in FIG. 1, the conventional sealing device includes a first seal ring member 100 and a first backup ring located on the back side of the first seal ring member 100 opposite to the sealed space side. Member 200. The first seal ring member 100 includes a first cylindrical portion 110 that is concentrically formed in a cylindrical shape on the outer peripheral side of a rotary shaft 900 (in FIG. 1, the outer peripheral surface position of the rotary shaft 900 is indicated by a two-dot chain line). The first seal lip portion 130 slidably contactable with the outer peripheral surface of the shaft 900, the first cylindrical portion 110 and the first seal lip portion 130 are connected to each other, and the shape of the back surface located on the side opposite to the sealed space side is It has the 1st curved part 120 currently formed in the substantially circular arc shape. The first backup ring member 200 is bent in correspondence with the second cylindrical portion 210 extending in close contact with the back surface of the first cylindrical portion 110, and the back surface 120a of the first bending portion 120 from the second cylindrical portion 210. The second bending portion 220 is provided.

  In the configuration of the first seal ring member 100 shown in FIG. 1, when the sealed fluid pressure is applied to the surface of the first seal ring member 100 on the sealed space side, the first seal ring member 100 is exposed to the atmosphere from the sealed space side. The first curved portion 120, particularly the substantially arc-shaped portion of the back surface 120a, is in contact with the distal end portion 220a of the second curved portion 220 of the first backup ring member 200, particularly the distal corner portion 230, The tip corner portion 230 tends to bite into the back surface 120a of the first bending portion 120. When this biting state occurs continuously for a long time or repeatedly occurs intermittently, a crack occurs at the biting position of the first bending portion 120, and this crack propagates in the thickness direction of the first bending portion 120. However, there is a possibility that the first seal ring member 100 may be damaged in the end, and if the first seal ring member 100 is damaged, the sealed state between the sealed space and the atmosphere cannot be maintained. is there.

  An object of the present invention is to optimize the position of the tip portion of the first backup ring member, thereby effectively suppressing the damage of the first seal ring member and applying the sealed fluid pressure. An object of the present invention is to provide a sealing device capable of stably supporting a member from the back side for a long period of time.

  In order to achieve the above object, the gist of the present invention is as follows.

  (1) A sealing device that seals a fluid in a sealed space by sealing between a housing having a shaft hole and a rotating shaft fitted in the shaft hole of the housing, the outer periphery of the rotating shaft A first cylindrical portion formed concentrically and cylindrically on the side, a first seal lip portion capable of sliding contact with an outer peripheral surface of the rotating shaft, and a connection between the first cylindrical portion and the first seal lip portion; A first seal ring member made of an elastomer having a first curved portion in which the shape of the back surface located on the side opposite to the sealed space side is formed in a substantially arc shape; and on the back side of the first seal ring member A second cylindrical portion that is positioned and extends in close contact with the back surface of the first cylindrical portion; and a second curved portion that is curved from the second cylindrical portion so as to correspond to the back surface of the first curved portion. In the sealing device comprising the first backup ring member of The second curved portion of the first backup ring member has a distal end portion extending in a direction of reducing the inner diameter from the innermost diameter position of the back surface of the first curved portion of the first seal ring member. , Sealing device.

  (2) a second seal ring member made of resin having a second seal lip portion located on the back side of the first backup ring member and capable of sliding contact with the outer peripheral surface of the rotary shaft; and the second seal ring member The sealing device according to (1), further comprising a second backup ring member made of metal that is positioned on the back side of the metal and supports the second seal ring member.

  (3) The sealing device further includes a cylindrical case that houses the first seal ring member, the first backup ring member, the second seal ring member, and the second backup ring member, The sealing device according to (1) or (2) above, further comprising an annular recess for mounting an elastically deformable O-ring in close contact with the inner peripheral surface of the shaft hole on the outer peripheral side.

  According to the present invention, the second curved portion of the first backup ring member has a distal end portion that extends in a direction of reducing the inner diameter from the innermost position of the back surface of the first curved portion of the first seal ring member made of elastomer. Accordingly, it is possible to provide a sealing device capable of stably supporting the first seal ring member on which the sealed fluid pressure acts from the back side over a long period of time while effectively suppressing damage to the first seal ring member. Became possible.

FIG. 1 is an enlarged partial cross-sectional view illustrating a mutual positional relationship between a first curved portion of a first seal ring member and a second curved portion of a first backup ring member in a conventional sealing device. It is. FIG. 2 is a half cross-sectional view of the sealing device of the present invention, and shows the disposition position of the rotary shaft when it is fitted in the shaft hole of the housing by a virtual line. FIG. 3 is a partial cross-sectional view showing only a portion of a region S surrounded by a square shown in FIG.

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

  FIG. 2 shows only a half of a longitudinal section of the sealing device 1 according to the present invention, and FIG. 3 shows an enlarged view of only a portion of a region S surrounded by a square shown in FIG. is there.

  The sealing device 1 shown in FIG. 2 mainly includes a first seal ring member 10 and a first backup ring member 20.

  The first seal ring member 10 is made of an elastomer, and can be slidably contacted with the first cylindrical portion 11 formed concentrically with the rotary shaft 90 and on the outer peripheral surface of the rotary shaft 90 on the outer peripheral side of the rotary shaft 90. The first seal lip portion 13 is connected to the first cylindrical portion 11 and the first seal lip portion 13, and the back surface 12a facing the atmosphere Y side opposite to the sealed space X is formed in a substantially arc shape. The first bending portion 12 is provided. Further, the first seal ring member 10 shown in FIG. 2 is connected to an end portion of the first cylindrical portion 11 that is located on the opposite side of the end portion connected to the first curved portion 12, and extends radially outward. The first thick base 14 is further provided. The tip end portion of the first seal lip portion 13 that contacts the outer peripheral surface of the rotating shaft 90 extends while inclining toward the sealing space X toward the rotating shaft 90, and rotates around the rotating axis 91. By elastically deforming the outer peripheral surface so as to be in close contact with a small contact area so as to have a low contact resistance, and increasing the surface pressure of the front end portion of the first seal lip portion 13 with respect to the outer peripheral surface of the rotating shaft 90 The function is exhibited and leakage of the sealed fluid from the sealed space X to the atmosphere Y side can be prevented.

  The first backup ring member 20 is made of metal, is located on the back side of the first seal ring member 10, and extends in close contact with the back surface of the first cylindrical portion 11, and the second cylindrical portion. 21 and a second curved portion 22 that is curved corresponding to the back surface of the first curved portion 12. The first backup ring member 20 is made of a metal plate such as a steel plate, and is provided to support the first seal ring member 10 by the sealed fluid pressure in the sealed space X from the back surface and limit deformation thereof. is there. The second curved portion 22 of the first backup ring member 20 has a tip portion 22a that extends radially inward. Further, the first backup ring member 20 shown in FIG. 1 further includes a first flange base portion 24 that extends radially outward from an end on the atmosphere Y side of the second cylindrical portion 21. The first backup ring member 20 is sandwiched between the first seal ring member 10 and a resin-made second seal ring member 30 described later at the first flange base 24.

  Furthermore, the sealing device 1 shown in FIG. 2 is positioned on the back side of the first backup ring member 20 from the viewpoint of further improving the sealing performance between the inner peripheral portion of the sealing device 1 and the outer peripheral surface of the rotating shaft 90. An example of an embodiment in which a second seal ring member 30 made of resin having a second seal lip portion 32 slidably contactable with the outer peripheral surface of the rotating shaft 90 is shown. The second seal ring member 30 is an annular second flange base portion disposed in close contact with the first thick base portion 14 of the first seal ring member 10 and the back surface of the first flange base portion 24 of the first backup ring member 20. 31 and a second seal lip portion 32 that extends from the second flange base portion 31 toward the rotary shaft 90 while inclining toward the sealed space X side. When the rotary shaft 90 is fitted into the shaft hole 81 of the housing 80 in which the sealing device 1 is mounted, the second seal ring member 30 is elastic like the first seal lip portion 13 of the first seal ring member 10. It deform | transforms and it will be in the state which closely contacted the outer peripheral surface of the rotating shaft 90 so that sliding contact was possible. The material of the second seal ring member 30 is not particularly defined, but it is preferable to use a low friction synthetic resin material such as polytetrafluoroethylene (PTFE).

  Furthermore, in the sealing device 1 shown in FIG. 2, the sealing device 1 is positioned on the back side of the second seal ring member 30 and supports the second seal ring member 30 in order to further improve the sealing performance with the outer peripheral surface of the rotating shaft 90. And a second backup ring member 40 made of metal.

  2 shows that the sealing device 1 has a pull ring 41 on the back side of the second backup ring member 40 for hooking a pulling jig when the sealing device 1 is further pulled out from the inner periphery of the housing 80 and removed. An example of an embodiment is shown.

  2 further includes a cylindrical case 70 that houses the first seal ring member 10, the first backup ring member 20, the second seal ring member 30, and the second backup ring member 40. This cylindrical case 70 has an annular recess 71 for mounting an elastically deformable O-ring 60 in close contact with the inner peripheral surface 82 of the shaft hole 81 on the outer peripheral side. Thereby, the sealing performance between the outer peripheral part of the sealing device 1 and the inner peripheral surface of the housing 80 can be ensured. The annular recess 71 is formed at the end of the cylindrical case 70 on the sealed space X side, and the end of the cylindrical case 70 on the atmosphere Y side is provided with a caulking portion 73 bent inward in the radial direction. Furthermore, the cylindrical case 70 has a third cylindrical portion 72 that connects the annular recess 71 and the caulking portion 73 and is formed concentrically with the rotating shaft 90 in a cylindrical shape. In addition, the cylindrical case 70 includes the first seal ring member 10, the first backup ring member 20, the second seal ring member 30, and the second backup ring member 40 between the annular recess 71 and the caulking portion 73. The housing 80 is configured to be press-fit into the shaft hole 81 of the housing 80 through an O-ring 60 attached to the annular recess 71 in a housing state in close contact with each other. The outer diameter of the O-ring 60 is set slightly larger than the maximum outer diameter of the cylindrical case 70 in FIG. 2, but the O-ring 60 is cylindrical when the sealing device 1 is fitted into the shaft hole 81 of the housing 80. It is elastically deformed to the same diameter as the outer peripheral surface of the case 70 and is firmly fixed.

  Further, the sealing device 1 shown in FIG. 2 has a reinforcing ring 50 embedded in the first seal ring member 10, particularly in the first thick base portion 14, and thereby, when the sealing device 1 is fitted. The shape of the first thick base portion 14 can be maintained and a tighter fitting of the sealing device 1 can be performed.

  As shown in FIG. 3, the main structural features of the present invention are that the distal end portion 22a of the second curved portion 22 of the first backup ring 20 with respect to the back surface of the first curved portion 12 of the first seal ring member 10. More specifically, the second curved portion 22 of the first backup ring member 20 has the innermost inner diameter of the back surface 12a of the first curved portion 12 of the first seal ring member 10. By having this configuration, the first seal ring member 10 is pressurized by the sealed fluid and pushed into the atmosphere Y side by having the tip 22a extending in the direction of reducing the inner diameter from the position P1. Even in this case, the tip corner portion 23 of the tip portion 22a of the second curved portion 22 of the first backup ring member 20 made of metal is the back surface 1 of the first curved portion 12 of the first seal ring member 10 made of elastomer. Results a phenomenon biting in contact with a occurs is eliminated, it is possible to avoid damage of the first seal ring member 10.

  The relationship between the innermost diameter position P1 of the back surface 12a of the first curved portion 12 of the first seal ring member 10 and the position Q1 of the distal end portion 22a of the second curved portion 22 of the first backup ring 20 is as shown in FIG. Furthermore, when the inner diameter at the innermost diameter position P1 of the back surface 12a of the first bending portion 12 is D1, and the inner diameter at the position Q of the distal end portion 22a of the second bending portion 22 is D2, in the sealing device 1 of the present invention, In the relationship of D1> D2, the distal end portion 22a of the second curved portion 22 of the first backup ring member 20 is radially inward from the innermost diameter position of the back surface of the first curved portion 12 of the first seal ring member 10. It is necessary to configure so as to protrude.

  On the other hand, in the case of the conventional sealing device shown in FIG. 1, the innermost diameter position P2 of the back surface 120a of the first bending portion 120 of the first seal ring member 100 and the second bending portion of the first backup ring 200. The relationship between the distal end portion 220a of the second bending portion 220 and the position Q2 is that the inner diameter of the back surface 120a of the first bending portion 120 at the innermost diameter position P2 is D1, and the inner diameter of the second bending portion 220 at the distal end portion 220a at the position Q2 is D2. In this case, the relationship is D2> D1. In this relationship, the front end portion 220a of the second curved portion 220 of the first backup ring member 200 is radially outside the innermost diameter position P2 of the back surface 120a of the first curved portion 120 of the first seal ring member 100, The tip corner portion 230 of the second curved portion 220 of the first backup ring member 200 is in contact with the back surface 120 a of the first curved portion 120. In such a configuration, the tip corner portion 230 of the tip portion 220a of the second curved portion 220 of the first backup ring member 200 made of metal is the back surface 120a of the first curved portion 120 of the first seal ring member 100 made of elastomer. The first seal ring member 100 is easily damaged from this biting portion.

  When the back surfaces 12a and 120a of the first bending portions 12 and 120 are in contact with the second bending portions 22 and 220 of the first backup ring members 20 and 200, the back surfaces 12a and 120a of the first bending portions 12 and 120 are in contact with each other. Stress will occur. In the state where the sealing device 1 is attached to the rotating shaft and press-fitted into the housing, the Mises stress generated on the back surface 120a of the first bending portion 120 was measured in the conventional configuration shown in FIG. In contrast, in the configuration according to the present invention shown in FIG. 3, the pressure is 1.6 MPa, and the Mises stress generated in the first bending portion 12 is reduced to two thirds.

  According to the present invention, the second curved portion 22 of the first backup ring member 20 extends in the direction of reducing the inner diameter from the innermost diameter position of the back surface 12a of the first curved portion 12 of the first seal ring member 10. By having 22a, it is possible to stably support the first seal ring member 10 on which the sealed fluid pressure acts from the back side over a long period of time while effectively suppressing damage to the first seal ring member 10. It is possible to provide a simple sealing device 1.

DESCRIPTION OF SYMBOLS 1 Sealing device 10 First seal ring member made of elastomer 11 First cylindrical portion 12 First curved portion 12a Back surface 13 First seal lip portion 14 First thick base portion 20 Metal first backup ring member 21 Second cylindrical portion 22 Second curved portion 22a Tip portion 23 Tip corner portion 24 First flange base portion 30 Second seal ring member 31 Second flange base portion 32 Second seal lip portion 40 Metal second backup ring member 41 Pull ring 50 Reinforcement ring 60 O Ring 70 Cylindrical case 71 Annular recess 72 Third cylindrical portion 73 Caulking portion 80 Housing 81 Axial hole 82 Inner circumferential surface of axial hole 90 Rotating shaft 91 Rotating axis 100 First seal ring member 110 First cylindrical portion 120 First curved portion 120a Back surface 130 First seal lip part 200 First backup ring member 210 Second cylindrical portion 220 Second curved portion 220a Tip portion 230 Tip corner portion 900 Rotating shaft 910 Rotation axis P1 Inner diameter position of back surface 12a P2 Inner diameter position of back surface 120a Q1 Position of tip portion 22a Q2 Position of tip portion 220a D1 First Inner diameter at the innermost position of the back surface of one curved portion D2 Inner diameter at the position of the distal end portion of the second curved portion X Sealed space Y Atmosphere S region

Claims (3)

A sealing device that seals a fluid in a sealed space by sealing between a housing having a shaft hole and a rotating shaft fitted in the shaft hole of the housing,
A first cylindrical portion formed concentrically and cylindrically on the outer peripheral side of the rotating shaft;
A first seal lip portion slidably contactable with an outer peripheral surface of the rotating shaft; and a shape of a back surface that connects between the first cylindrical portion and the first seal lip portion and is located on the side opposite to the sealed space side A first seal ring member made of elastomer having a first curved portion formed in a substantially arc shape;
Located on the back side of the first seal ring member,
A metal first having a second cylindrical portion extending in close contact with the back surface of the first cylindrical portion, and a second curved portion curved from the second cylindrical portion corresponding to the back surface of the first curved portion. In a sealing device comprising a backup ring member,
The second curved portion of the first backup ring member has a distal end portion extending in a direction of reducing the inner diameter from the innermost diameter position of the back surface of the first curved portion of the first seal ring member. , Sealing device. Located on the back side of the first backup ring member,
A resin-made second seal ring member having a second seal lip portion slidably contactable with the outer peripheral surface of the rotating shaft;
2. The sealing device according to claim 1, further comprising a second backup ring member made of metal and positioned on the back side of the second seal ring member and supporting the second seal ring member.   The sealing device further includes a cylindrical case that accommodates the first seal ring member, the first backup ring member, the second seal ring member, and the second backup ring member, and the cylindrical case has an outer peripheral side. The seal device according to claim 1, further comprising an annular recess for mounting an elastically deformable O-ring in close contact with the inner peripheral surface of the shaft hole.

Images