JP2013194764A - Sealing device and sealing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device and a sealing structure allowing a sealing function to be exerted even while fluid pressure is low while suppressing sliding torque low.SOLUTION: A sealing device includes a resin-made seal ring 210 tightly adhering to an inner circumferential surface of a shaft hole, a sliding ring 310 sliding a side wall surface 212 of the seal ring 210 and a pressing member 410 pressing the sliding ring 310 toward a high pressure side (H). At no load, a seal portion is formed between the seal ring 210 and a tapered surface 611 and between an outer circumferential surface of the seal ring 210 and an inner circumferential surface of the shaft hole. At high pressure, the seal portion is formed at least between an outer circumferential surface of the seal ring 210 and an inner circumferential surface of the shaft hole and between the seal ring 210 and the sliding ring 310.

Description

  The present invention relates to a sealing device and a sealing structure for sealing an annular gap between a shaft and a shaft hole of a housing.

  In ATs and CVTs for automobiles, a seal ring for sealing an annular gap between a relatively rotating shaft and a housing is provided in order to maintain hydraulic pressure. With reference to FIG.22 and FIG.23, the seal ring which concerns on a prior art example is demonstrated. FIG. 22 is a schematic cross-sectional view showing a state in which the hydraulic pressure in the seal ring according to the conventional example is not maintained. FIG. 23 is a schematic cross-sectional view showing a state in which the hydraulic pressure is maintained in the seal ring according to the conventional example. In the case of the seal ring 900 according to the conventional example, the seal ring 900 is attached to the annular groove 810 provided on the outer periphery of the shaft 800, and the inner peripheral surface of the shaft hole of the housing 700 through which the shaft 800 is inserted and the side wall surface of the annular groove 810. It is comprised so that the annular clearance between the axis | shaft 800 and the shaft hole of the housing 700 may be sealed by contacting slidably.

  In the seal ring 900 used in the above applications, it is required that the sliding torque be sufficiently low. Therefore, the peripheral length of the outer peripheral surface of the seal ring 900 is configured to be shorter than the peripheral length of the inner peripheral surface of the shaft hole of the housing 700, and is configured not to have a tightening allowance. Therefore, in a state where the engine of the automobile is applied and the hydraulic pressure is high, the seal ring 900 is expanded by the hydraulic pressure, and is sufficiently in close contact with the inner peripheral surface of the shaft hole and the side wall surface of the annular groove 810. The function is exhibited (see FIG. 23). On the other hand, the seal ring 900 is configured to be separated from the inner peripheral surface of the shaft hole and the side wall surface of the annular groove 810 in a state where no hydraulic pressure is applied due to the stop of the engine (see FIG. 22).

  However, in the case of the seal ring 900 configured as described above, the sealing function is not exhibited in a state where no hydraulic pressure is applied. Therefore, in a configuration in which the shift control is performed by the oil pumped by the hydraulic pump such as AT and CVT, the seal ring 900 is sealed in the no-load state where the hydraulic pump is stopped (for example, when idling is stopped). The oil returns to the oil pan without being sealed, and the oil in the vicinity of the seal ring 900 is lost. Therefore, when the engine is started (restarted) from this state, there is a problem that the response and the operability are poor because the operation is started in a state where there is no oil in the vicinity of the seal ring 900 and there is no lubrication.

Japanese Patent No. 4665046 JP 2010-265937 A Japanese Patent No. 4196946 JP 2004-28273 A

  An object of the present invention is to provide a sealing device and a sealing structure capable of exhibiting a sealing function even when the fluid pressure is low while keeping the sliding torque low.

  The present invention employs the following means in order to solve the above problems.

That is, the sealing device of the present invention is
An annular groove provided on the outer periphery of the shaft, and mounted on the annular groove having a tapered surface whose diameter increases from the low pressure side toward the high pressure side on the side wall surface on the high pressure side, and the shaft rotating relatively A sealing device that seals an annular gap between a housing and maintains fluid pressure in a region to be sealed configured to change fluid pressure,
A resin seal ring that is in close contact with the inner peripheral surface of the shaft hole through which the shaft of the housing is inserted;
A sliding ring that is disposed on the low pressure side of the seal ring and slides against a side wall surface of the seal ring;
A pressing member that presses the sliding ring toward the high-pressure side;
With
In a state where the seal ring is pressed to the high pressure side via the sliding ring by the pressing member and the inner peripheral side of the seal ring is in contact with the tapered surface of the annular groove, the seal ring and the tapered surface And between the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole,
In a state where the seal ring is separated from the tapered surface of the annular groove against the pressing force by the pressing member due to the fluid pressure on the high pressure side, at least the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole And a seal portion is formed between the seal ring and the sliding ring.

The sealing structure of the present invention is
A shaft provided on the outer periphery with an annular groove having a tapered surface expanding from the low pressure side to the high pressure side on the side wall surface on the high pressure side;
A housing having a shaft hole through which the shaft is inserted;
A sealing device that is mounted in the annular groove and seals the annular gap between the relatively rotating shaft and the housing, and holds the fluid pressure in the region to be sealed configured to change the fluid pressure; A sealing structure comprising:
The sealing device includes:
A resin seal ring that is in close contact with the inner peripheral surface of the shaft hole;
A sliding ring that is disposed on the low pressure side of the seal ring and slides against a side wall surface of the seal ring;
A pressing member that presses the sliding ring toward the high-pressure side;
With
In a state where the seal ring is pressed to the high pressure side via the sliding ring by the pressing member and the inner peripheral side of the seal ring is in contact with the tapered surface of the annular groove, the seal ring and the tapered surface And between the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole,
In a state where the seal ring is separated from the tapered surface of the annular groove against the pressing force by the pressing member due to the fluid pressure on the high pressure side, at least the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole And a seal portion is formed between the seal ring and the sliding ring.

  In the present invention, the “high pressure side” means a side that becomes high pressure when differential pressure is generated on both sides of the sealing device, and the “low pressure side” means that differential pressure is generated on both sides of the sealing device. It means the side that is at low pressure.

According to the present invention, the seal ring is pressed to the high pressure side by the pressing member via the sliding ring, and receives a force from the tapered surface toward the outer peripheral side when the inner peripheral side is in contact with the tapered surface of the annular groove. . Therefore, the seal ring is deformed in the diameter increasing direction, and fluid pressure is not applied (no differential pressure is generated) or fluid pressure is hardly applied (differential pressure is hardly generated). The seal ring is in contact with the inner peripheral surface of the shaft hole of the housing, and a sealing function is exhibited. Therefore, the fluid pressure can be maintained immediately after the fluid pressure in the seal target region starts to increase.

  Further, when the seal ring is separated from the tapered surface of the annular groove against the pressing force by the pressing member due to the fluid pressure on the high pressure side, at least between the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole. And a seal portion is formed between the seal ring and the sliding ring. Thereby, the seal ring of this invention can implement | achieve the sealing mechanism similar to the conventional seal ring which reduced the sliding torque.

  With the fluid pressure on the high pressure side, the seal ring is separated from the tapered surface of the annular groove against the pressing force by the pressing member, and further, the sliding ring and the side wall surface on the low pressure side in the annular groove A seal portion may be formed between the two.

The pressing member is a rubber ring made of a rubber-like elastic body,
In a state where the seal ring is separated from the tapered surface of the annular groove against the pressing force by the pressing member due to the fluid pressure on the high pressure side, and further between the sliding ring and the rubber ring, and the rubber It is also preferable to form a seal portion between the ring and the low-pressure side wall surface of the annular groove.

  As described above, according to the present invention, the sealing function can be exhibited even when the fluid pressure is low while the sliding torque is kept low.

FIG. 1 is a schematic cross-sectional view showing an unloaded state in the sealing structure according to Embodiment 1 of the present invention. FIG. 2 is a schematic cross-sectional view showing a high-pressure state in the sealing structure according to Embodiment 1 of the present invention. FIG. 3 is a side view of the seal ring in the sealing device according to Embodiment 1 of the present invention. FIG. 4 is a view as seen from the outer peripheral surface side of the seal ring in the sealing device according to Embodiment 1 of the present invention. FIG. 5 is a schematic cross-sectional view of a seal ring in the sealing device according to Embodiment 1 of the present invention. FIG. 6 is a schematic cross-sectional view showing an unloaded state in the sealing structure according to Embodiment 2 of the present invention. FIG. 7 is a schematic cross-sectional view showing a high-pressure state in the sealing structure according to Embodiment 2 of the present invention. FIG. 8 is a side view of the seal ring in the sealing device according to Embodiment 2 of the present invention. FIG. 9 is a view as seen from the outer peripheral surface side of the seal ring in the sealing device according to Embodiment 2 of the present invention. FIG. 10 is a schematic cross-sectional view of a seal ring in a sealing device according to Embodiment 2 of the present invention. FIG. 11: is typical sectional drawing which shows the no-load state in the sealing structure which concerns on Example 3 of this invention. FIG. 12 is a schematic cross-sectional view showing a high-pressure state in the sealing structure according to Embodiment 3 of the present invention. FIG. 13: is typical sectional drawing which shows the no-load state in the sealing structure which concerns on Example 4 of this invention. FIG. 14 is a schematic cross-sectional view showing a high pressure state in the sealing structure according to Embodiment 4 of the present invention. FIG. 15 is a side view of a seal ring in the sealing device according to Embodiment 4 of the present invention. FIG. 16 is a view as seen from the outer peripheral surface side of the seal ring in the sealing device according to Embodiment 4 of the present invention. FIG. 17 is a schematic cross-sectional view of a seal ring in a sealing device according to Embodiment 4 of the present invention. FIG. 18 is a schematic cross-sectional view showing an unloaded state in the sealing structure according to Embodiment 5 of the present invention. FIG. 19 is a schematic cross-sectional view showing a high pressure state in the sealing structure according to Embodiment 5 of the present invention. FIG. 20 is a schematic cross-sectional view showing an unloaded state in the sealing structure according to Embodiment 6 of the present invention. FIG. 21 is a schematic cross-sectional view showing a high-pressure state in the sealing structure according to Example 6 of the present invention. FIG. 22 is a schematic cross-sectional view showing a state in which the hydraulic pressure in the seal ring according to the conventional example is not maintained. FIG. 23 is a schematic cross-sectional view showing a state in which the hydraulic pressure is maintained in the seal ring according to the conventional example.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be exemplarily described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to those unless otherwise specified. . The sealing device according to the present embodiment is used for sealing an annular gap between a relatively rotating shaft and a housing in order to maintain hydraulic pressure in a transmission such as an AT or CVT for an automobile. It is used. Further, in the following description, “high pressure side” means a side that becomes high pressure when differential pressure occurs on both sides of the sealing device, and “low pressure side” means that differential pressure occurs on both sides of the sealing device. This means the side that is at low pressure.

Example 1
With reference to FIGS. 1-5, the sealing apparatus and sealing structure which concern on Example 1 of this invention are demonstrated.

<Configuration of sealing device and sealing structure>
With reference to FIGS. 1-5, the structure of the sealing device and sealing structure which concern on a present Example is demonstrated. The sealing device 110 according to the present embodiment is mounted in an annular groove 610 provided on the outer periphery of the shaft 600, and rotates relative to the shaft 600 and the housing 700 (the inner periphery of the shaft hole through which the shaft 600 in the housing 700 is inserted. The annular gap between the first and second surfaces is sealed. As a result, the sealing device 110 maintains the fluid pressure in the region to be sealed configured so that the fluid pressure (hydraulic pressure in this embodiment) changes. Here, in the present embodiment, the fluid pressure in the region on the right side in FIGS. 1 and 2 is configured to change, and the sealing device 110 serves to maintain the fluid pressure in the region to be sealed on the right side in the drawings. Is responsible. When the automobile engine is stopped, the fluid pressure in the seal target area is low and no load is applied. When the engine is started, the fluid pressure in the seal target area increases.

The shaft 600 has a shaft body 600 </ b> A and a shaft body 60 in order to facilitate attachment / detachment of the sealing device 110.
The annular member 600B is fixed to 0A. A tapered surface 611 whose diameter increases from the low pressure side (L) to the high pressure side (H) is formed on the side wall surface on the high pressure side (H) in the annular groove 610 provided on the outer periphery of the shaft 600.

  The sealing device 110 includes a seal ring 210 made of resin such as polyetheretherketone (PEEK), a sliding ring 310 made of a rigid body such as a resin material or a metal material, and the sliding ring 310 facing the high pressure side (H). And a pressing member 410 that presses.

  The seal ring 210 includes a joint portion 210c at one place in the circumferential direction. The joint portion 210c according to the present embodiment employs a so-called special step cut which is cut in a step shape when viewed from either the outer peripheral surface side or both side wall surfaces. Since the special step cut is a known technique, a detailed description thereof is omitted, but it has a characteristic of maintaining a stable sealing performance even if the circumference of the seal ring 210 is changed due to thermal expansion and contraction. In addition, although the case of the special step cut was shown here as an example of the abutment part 210c, about the abutment part 210c, not only this but a straight cut, a bias cut, a step cut (on the outer peripheral surface side and the inner peripheral surface side) The structure cut | disconnected in the staircase shape etc. can be employ | adopted from any viewpoint.

  Further, in the vicinity of the seal ring 210 according to the present embodiment except for the joint portion 210c, the cross-sectional shape cut along the plane passing through the axis is a pentagon as shown in FIG. 5 is a cross-sectional view taken along line AA in FIG. More specifically, the seal ring 210 has a tapered surface 213 whose diameter increases toward the high-pressure side (H) on the inner peripheral side and the high-pressure side (H) except for the vicinity of the joint portion 210c. Further, the low pressure side (L) has a tapered surface 214 whose diameter increases toward the low pressure side (L).

  The circumferential length of the outer circumferential surface 211 of the seal ring 210 according to the present embodiment is configured to be shorter than the circumferential length of the inner circumferential surface of the shaft hole of the housing 700, and is configured to have no fastening allowance. Therefore, if no external force is applied, the outer peripheral surface 211 of the seal ring 210 does not contact the inner peripheral surface of the shaft hole of the housing 700. However, as will be described later, when used, the outer peripheral surface 211 of the seal ring 210 is in close contact with the inner peripheral surface of the shaft hole of the housing 700.

  The sliding ring 310 is composed of an annular member and has a rotationally symmetric shape. The sliding ring 310 has a tapered surface 312 which is reduced in diameter toward the high pressure side (H) on the inner peripheral side and the high pressure side (H). The sliding ring 310 is provided with an annular convex portion 313 that protrudes toward the low pressure side (L) on the outer peripheral side and the low pressure side (L). The sliding ring 310 is disposed on the low pressure side (L) of the seal ring 210. In use, the high pressure side (H) side wall surface 311 of the sliding ring 310 and the low pressure side (L) side wall surface 212 of the seal ring 210 slide.

  The pressing member 410 is disposed between the low pressure side (L) side wall surface of the annular groove 610 and the sliding ring 310. Further, the pressing member 410 is disposed on the inner peripheral side with respect to the annular convex portion 313 of the sliding ring 310. The pressing member 410 is not particularly limited as long as the sliding ring 310 can be pressed to the high pressure side (L), and for example, a rubber ring made of a rubber-like elastic body, a coil spring, or the like can be adopted.

<Mechanism when using sealing device>
In particular, with reference to FIG. 1 and FIG. 2, a mechanism during use of the sealing device 110 according to the present embodiment will be described. FIG. 1 shows a state in which the engine is stopped and there is no differential pressure in the left and right regions (or almost no differential pressure) via the sealing device 110 and there is no load. FIG. 2 shows a state in which the engine is started and the fluid pressure in the right region is higher than the left region through the sealing device 110.

  In the no-load state, the seal ring 210 is pressed to the high pressure side (H) by the pressing member 410 via the sliding ring 310, and the edge 215 on the high pressure side (H) and the inner circumferential side has the annular groove 610. The state is in contact with the tapered surface 611. Further, at this time, the seal ring 210 is such that the low pressure side (L) side wall surface 212 is pressed against the high pressure side (H) side wall surface 311 of the sliding ring 310 and the low pressure side (L) inner end side end. The edge 216 is pressed against the tapered surface 312 of the sliding ring 310. Therefore, the seal ring 210 receives a force toward the outer peripheral side from the tapered surface 611 of the annular groove 610 and the tapered surface 312 of the sliding ring 310. As a result, the seal ring 210 is deformed in the diameter increasing direction, and the outer peripheral surface 211 of the seal ring 210 is in close contact with the inner peripheral surface of the shaft hole of the housing 700. The taper angles of the taper surfaces 213 and 214 in the seal ring 210 are set larger than the taper angles of the taper surface 611 of the annular groove 610 and the taper surface 312 of the sliding ring 310. Further, the taper angle of the tapered surface 611 of the annular groove 610 and the taper angle of the tapered surface 312 of the sliding ring 310 are set to be equal. Thereby, the seal ring 210 receives the force toward the outer peripheral side equally from both the tapered surface 611 of the annular groove 610 and the tapered surface 312 of the sliding ring 310.

  With the above configuration, in the no-load state, the seal portion S1 is formed between the outer peripheral surface 211 of the seal ring 210 and the inner peripheral surface of the shaft hole of the housing 700, and the inner peripheral side of the seal ring 210 is A seal portion S2 is formed between the end edge 215 and the tapered surface 611 of the annular groove 610. Thus, in the no-load state, the sealing device 110 forms the two seal portions S1 and S2 to seal the annular gap between the shaft 600 and the housing 700.

  In the state where the engine is started and the differential pressure is generated, the seal ring 210 and the sliding member are opposed to the pressing force by the pressing member 410 by the fluid pressure from the high pressure side (H) as shown in FIG. The ring 310 moves to the low pressure side (L). When the differential pressure becomes a certain level or more, the sliding ring 310 is in a state in which the tip surface 313a of the annular protrusion 313 is in close contact with the side wall surface on the low pressure side (L) of the annular groove 610.

  The seal ring 210 is maintained in a state of being deformed in the diameter-expanding direction by the fluid pressure from the inner peripheral surface side, and the outer peripheral surface 211 of the seal ring 210 is maintained in close contact with the inner peripheral surface of the shaft hole of the housing 700. . The seal ring 210 is pressed against the sliding ring 310 by the fluid pressure from the high pressure side (H). Thereby, the state where the low pressure side (L) side wall surface 212 of the seal ring 210 and the high pressure side (H) side wall surface 311 of the sliding ring 310 are in contact with each other is maintained. Here, the contact area between the outer peripheral surface 211 of the seal ring 210 and the inner peripheral surface of the shaft hole of the housing 700 is such that the side wall surface 212 on the low pressure side (L) of the seal ring 210 and the high pressure side of the sliding ring 310 ( H) is set to be sufficiently larger than the contact area with the side wall surface 311. Therefore, while the shaft 600 and the housing 700 are rotating relatively, between the low pressure side (L) side wall surface 212 of the seal ring 210 and the high pressure side (H) side wall surface 311 of the sliding ring 310. Slide on. Note that there is no sliding between the outer peripheral surface 211 of the seal ring 210 and the inner peripheral surface of the shaft hole of the housing 700.

With the above configuration, in a state where a differential pressure is generated (high pressure state), the low pressure side (L) of the seal ring 210 is between the outer peripheral surface 211 of the seal ring 210 and the inner peripheral surface of the shaft hole of the housing 700. The side wall surface 212 of the sliding ring 310 and the side wall surface 311 on the high pressure side (H) of the sliding ring 310 and the side wall surface of the sliding ring 310 on the low pressure side (L) of the tip surface 313a of the annular protrusion 313 and the annular groove 610. Seal portions S1, S2 and S3 are formed respectively. However, when the pressing member 410 is a rubber ring, there are seal portions between the pressing member 410 and the sliding ring 310 and between the pressing member 410 and the low-pressure side (L) side wall surface of the annular groove 610, respectively. It is formed. Therefore, in this case, it is not necessary to form a seal portion between the tip end surface 313a of the annular protrusion 313 and the low-pressure side (L) side wall surface of the annular groove 610 in the sliding ring 310. Therefore, since it is not necessary to make the front end surface 313a of the annular convex part 313 in the sliding ring 310 contact the low pressure side (L) side wall surface of the annular groove 610, the annular convex part 313 may not be provided.

<Excellent points of sealing device and sealing structure according to this embodiment>
According to the present embodiment, the seal ring 210 is pressed to the high pressure side (H) by the pressing member 410 via the sliding ring 310, and the outer periphery from the tapered surface 611 of the annular groove 610 and the tapered surface 312 of the sliding ring 310. Receive the force toward the side. As a result, the seal ring 210 is deformed in the diameter increasing direction, and the outer peripheral surface 211 of the seal ring 210 is in close contact with the inner peripheral surface of the shaft hole of the housing 700. Therefore, even when fluid pressure is not acting (no differential pressure is generated) or fluid pressure is hardly acting (almost no differential pressure is generated), the seal ring 210 remains in the shaft hole of the housing 700. It will be in the state which contact | connected the inner peripheral surface and the sealing function will be exhibited. Therefore, the fluid pressure can be maintained immediately after the fluid pressure in the seal target region starts to increase. That is, in an engine having an idling stop function, the hydraulic pressure can be maintained immediately after the hydraulic pressure on the seal target region side is increased by starting the engine when the accelerator is depressed from the engine stopped state.

  Further, when the seal ring 210 is separated from the tapered surface 611 of the annular groove 610 against the pressing force by the pressing member 410 due to the fluid pressure on the high pressure side (H), the seal ring 210 Seal portions are formed between the outer peripheral surface 211 and the inner peripheral surface of the shaft hole, and between the seal ring 210 and the sliding ring 310. That is, when focusing only on the seal ring 210, the sealing mechanism is the same as that of a general seal ring. Thereby, a sliding torque can be reduced equivalent to the conventional seal ring which reduced the sliding torque.

  Thus, in the case of the seal ring according to the conventional example, by adopting a configuration that reduces the sliding torque, the sealing function was not exhibited in a state where the fluid pressure was not acting, According to the sealing device 110 according to the present embodiment, the sealing function can be exhibited even in a state where the fluid pressure is not applied although the configuration for reducing the sliding torque is adopted.

(Example 2)
6 to 10 show a second embodiment of the present invention. In the present embodiment, only the structure of the seal ring is different from that of the first embodiment. Since other configurations and operations are the same as those in the first embodiment, the same components are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

  Also in the sealing device 120 according to the present embodiment, as in the case of the first embodiment, a seal ring 220 made of resin such as polyether ether ketone (PEEK) and a sliding made of a rigid body such as a resin material or a metal material. It is comprised from the ring 310 and the press member 410 which presses the sliding ring 310 toward a high voltage | pressure side (H). Since the sliding ring 310 and the pressing member 410 have the same configuration as in the first embodiment, description thereof is omitted.

  Also in the seal ring 220 according to the present embodiment, similarly to the first embodiment, the joint portion 220c is provided at one place in the circumferential direction. And also in the abutment part 220c which concerns on a present Example, what is called the special step cut cut | disconnected in step shape is employ | adopted even if it sees from any of an outer peripheral surface side and a both-sides wall surface side. Note that a straight cut, a bias cut, a step cut, or the like may be employed for the joint portion 220c.

  Further, in the seal ring 220 according to the present embodiment, in the vicinity excluding the joint portion 220c, the cross-sectional shape cut along the plane passing through the axis is a T-shape as shown in FIG. 10 is a cross-sectional view taken along the line BB in FIG. More specifically, the seal ring 220 has recesses 223 and 224 on the inner peripheral side and the high pressure side (H) and on the inner peripheral side and the low pressure side (L), respectively, except for the vicinity of the joint portion 220c.

  The circumferential length of the outer circumferential surface 221 of the seal ring 220 according to the present embodiment is configured to be shorter than the circumferential length of the inner circumferential surface of the shaft hole of the housing 700, and is configured to have no fastening allowance. Therefore, if no external force acts, the outer peripheral surface 221 of the seal ring 220 does not contact the inner peripheral surface of the shaft hole of the housing 700. However, as in the case of the first embodiment, the outer peripheral surface 221 of the seal ring 220 is in close contact with the inner peripheral surface of the shaft hole of the housing 700 during use.

  Here, FIG. 6 shows an unloaded state in which the engine is stopped and there is no differential pressure between the left and right regions (or almost no differential pressure) via the sealing device 120. FIG. 7 shows a state in which the engine is started and the fluid pressure in the right region is higher than the left region through the sealing device 120.

  In the no-load state, the seal ring 220 is pressed to the high pressure side (H) by the pressing member 410 via the sliding ring 310, and the end 225 on the high pressure side (H) and the inner peripheral side has the annular groove 610. The state is in contact with the tapered surface 611. Further, at this time, the seal ring 220 has a low-pressure side (L) side wall surface 222 pressed against a high-pressure side (H) side wall surface 311 of the sliding ring 310 and a low-pressure side (L) inner end side end. The edge 226 is pressed against the tapered surface 312 of the sliding ring 310. Therefore, the seal ring 220 receives a force toward the outer peripheral side from the tapered surface 611 of the annular groove 610 and the tapered surface 312 of the sliding ring 310. As a result, the seal ring 220 is deformed in the diameter increasing direction, and the outer peripheral surface 221 of the seal ring 220 is in close contact with the inner peripheral surface of the shaft hole of the housing 700.

  With the above configuration, in the no-load state, the seal portion S1 is formed between the outer peripheral surface 221 of the seal ring 220 and the inner peripheral surface of the shaft hole of the housing 700, and the inner peripheral side of the seal ring 220 is formed. A seal portion S <b> 2 is formed between the end edge 225 and the tapered surface 611 of the annular groove 610. Thus, in the no-load state, the sealing device 120 forms the two seal portions S1, S2 to seal the annular gap between the shaft 600 and the housing 700.

  Then, in the state where the engine is started and the differential pressure is generated, the seal ring 220 and the sliding member are opposed to the pressing force by the pressing member 410 by the fluid pressure from the high pressure side (H) as shown in FIG. The ring 310 moves to the low pressure side (L). When the differential pressure becomes a certain level or more, the sliding ring 310 is in a state in which the tip surface 313a of the annular protrusion 313 is in close contact with the side wall surface on the low pressure side (L) of the annular groove 610.

The seal ring 220 is maintained in a state in which the seal ring 220 is deformed in the diameter expansion direction by the fluid pressure from the inner peripheral surface side, and the outer peripheral surface 221 of the seal ring 220 is maintained in close contact with the inner peripheral surface of the shaft hole of the housing 700. . The seal ring 220 is pressed against the sliding ring 310 by the fluid pressure from the high pressure side (H). Thereby, the state where the low pressure side (L) side wall surface 222 of the seal ring 220 and the high pressure side (H) side wall surface 311 of the sliding ring 310 are in contact with each other is maintained. Here, the contact area between the outer peripheral surface 221 of the seal ring 220 and the inner peripheral surface of the shaft hole of the housing 700 is such that the side wall surface 222 on the low pressure side (L) of the seal ring 220 and the high pressure side of the sliding ring 310 ( H) is set to be sufficiently larger than the contact area with the side wall surface 311. Therefore, while the shaft 600 and the housing 700 are relatively rotated, the space between the low pressure side (L) side wall surface 222 of the seal ring 220 and the high pressure side (H) side wall surface 311 of the sliding ring 310 is between. Slide on. In addition, it does not slide between the outer peripheral surface 221 of the seal ring 220 and the inner peripheral surface of the shaft hole of the housing 700.

  With the above configuration, in a state where a differential pressure is generated (high pressure state), the low pressure side (L) of the seal ring 220 is between the outer peripheral surface 221 of the seal ring 220 and the inner peripheral surface of the shaft hole of the housing 700. Between the side wall surface 222 of the sliding ring 310 and the side wall surface 311 on the high pressure side (H) of the sliding ring 310, and the side wall surface on the low pressure side (L) of the annular protrusion 313 and the annular groove 610 on the sliding ring 310. Seal portions S1, S2 and S3 are formed respectively. However, when the pressing member 410 is a rubber ring, there are seal portions between the pressing member 410 and the sliding ring 310 and between the pressing member 410 and the low-pressure side (L) side wall surface of the annular groove 610, respectively. It is formed. Therefore, in this case, it is not necessary to form a seal portion between the tip end surface 313a of the annular protrusion 313 and the low-pressure side (L) side wall surface of the annular groove 610 in the sliding ring 310. Therefore, since it is not necessary to make the front end surface 313a of the annular convex part 313 in the sliding ring 310 contact the low pressure side (L) side wall surface of the annular groove 610, the annular convex part 313 may not be provided.

  As described above, also in the sealing device 120 according to the present embodiment, the same effect as in the case of the first embodiment can be obtained.

(Example 3)
11 and 12 show a third embodiment of the present invention. In the present embodiment, only the structure of the sliding ring is different from that of the first embodiment. Since other configurations and operations are the same as those in the first embodiment, the same components are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

  Also in the sealing device 130 according to the present embodiment, as in the case of the first embodiment, a seal ring 210 made of a resin such as polyether ether ketone (PEEK) and a sliding made of a rigid body such as a resin material or a metal material. It is comprised from the ring 330 and the press member 410 which presses the sliding ring 330 toward a high voltage | pressure side (H). Since the seal ring 210 and the pressing member 410 have the same configuration as in the first embodiment, description thereof is omitted.

  Similarly to the case of the first embodiment, the sliding ring 330 according to the present embodiment is also formed of an annular member and has a rotationally symmetric shape. As in the case of the first embodiment, the sliding ring 330 is provided with an annular convex portion 333 that protrudes toward the low pressure side (L) on the outer peripheral side and the low pressure side (L). And in the case of the sliding ring 330 which concerns on a present Example, the high voltage | pressure side (H) is comprised by the plane, and the taper surface is not formed like the case of Example 1. FIG.

  The sliding ring 330 is disposed on the low pressure side (L) of the seal ring 210. In use, the high pressure side (H) side wall surface 331 of the sliding ring 330 and the low pressure side (L) side wall surface 212 of the seal ring 210 slide.

  Here, FIG. 11 shows an unloaded state in which the engine is stopped and there is no differential pressure in the left and right regions (or almost no differential pressure) via the sealing device 130. FIG. 12 shows a state in which the engine is started and the fluid pressure in the right region is higher than that in the left region through the sealing device 130.

In the no-load state, the seal ring 210 is pressed to the high pressure side (H) by the pressing member 410 via the sliding ring 330, and the edge 215 on the high pressure side (H) and the inner peripheral side is the annular groove 610. The state is in contact with the tapered surface 611. At this time, the low pressure side (L) side wall surface 212 of the seal ring 210 is pressed against the high pressure side (H) side wall surface 331 of the sliding ring 330. In the case of the present embodiment, the high pressure side (H) of the sliding ring 330 is configured as a flat surface, and unlike the case of the first embodiment, the low pressure side (L) and the inner peripheral side of the seal ring 210. The edge 216 is not pressed by the sliding ring 330. Therefore, in the case of the present embodiment, the seal ring 210 receives a force toward the outer peripheral side only from the tapered surface 611 of the annular groove 610. As a result, the seal ring 210 is deformed in the diameter increasing direction, and the outer peripheral surface 211 of the seal ring 210 is in close contact with the inner peripheral surface of the shaft hole of the housing 700.

  With the above configuration, in the no-load state, the seal portion S1 is formed between the outer peripheral surface 211 of the seal ring 210 and the inner peripheral surface of the shaft hole of the housing 700, and the inner peripheral side of the seal ring 210 is A seal portion S2 is formed between the end edge 215 and the tapered surface 611 of the annular groove 610. As described above, in the no-load state, the sealing device 130 forms the two seal portions S <b> 1 and S <b> 2 to seal the annular gap between the shaft 600 and the housing 700.

  Then, in a state where the engine is started and a differential pressure is generated, the seal ring 210 and the sliding member are opposed to the pressing force by the pressing member 410 by the fluid pressure from the high pressure side (H) as shown in FIG. The ring 330 moves to the low pressure side (L). When the differential pressure exceeds a certain level, the sliding ring 330 is in a state where the tip surface 333a of the annular protrusion 333 is in close contact with the side wall surface on the low pressure side (L) of the annular groove 610.

  The seal ring 210 is maintained in a state of being deformed in the diameter-expanding direction by the fluid pressure from the inner peripheral surface side, and the outer peripheral surface 211 of the seal ring 210 is maintained in close contact with the inner peripheral surface of the shaft hole of the housing 700. . The seal ring 210 is pressed against the sliding ring 330 by the fluid pressure from the high pressure side (H). Thereby, the state where the low pressure side (L) side wall surface 212 of the seal ring 210 and the high pressure side (H) side wall surface 331 of the sliding ring 330 are in contact with each other is maintained. Here, the contact area between the outer peripheral surface 211 of the seal ring 210 and the inner peripheral surface of the shaft hole of the housing 700 is such that the side wall surface 212 on the low pressure side (L) of the seal ring 210 and the high pressure side of the sliding ring 330 ( H) is set to be sufficiently larger than the contact area with the side wall surface 331. Therefore, while the shaft 600 and the housing 700 are relatively rotated, the space between the low pressure side (L) side wall surface 212 of the seal ring 210 and the high pressure side (H) side wall surface 331 of the sliding ring 330 is between. Slide on. Note that there is no sliding between the outer peripheral surface 211 of the seal ring 210 and the inner peripheral surface of the shaft hole of the housing 700.

  With the above configuration, in a state where a differential pressure is generated (high pressure state), the low pressure side (L) of the seal ring 210 is between the outer peripheral surface 211 of the seal ring 210 and the inner peripheral surface of the shaft hole of the housing 700. Between the side wall surface 212 and the high-pressure side (H) side wall surface 331 of the sliding ring 330, and the low-pressure side (L) side wall surface of the annular protrusion 333 and the low-pressure side (L) of the annular groove 610 in the sliding ring 330. Seal portions S1, S2 and S3 are formed respectively. However, when the pressing member 410 is a rubber ring, there are seal portions between the pressing member 410 and the sliding ring 330 and between the pressing member 410 and the low-pressure side (L) side wall surface of the annular groove 610, respectively. It is formed. Therefore, in this case, it is not necessary to form a seal portion between the tip surface 333 a of the annular convex portion 333 in the sliding ring 330 and the low-pressure side (L) side wall surface of the annular groove 610. Therefore, since it is not necessary to make the front end surface 333a of the annular convex part 333 in the sliding ring 330 contact the low pressure side (L) side wall surface of the annular groove 610, the annular convex part 333 need not be provided.

As described above, also in the sealing device 130 according to the present embodiment, the same effect as in the case of the first embodiment can be obtained. Also in this embodiment, the seal ring 220 having the T-shaped cross section shown in the second embodiment can be used.

Example 4
With reference to FIGS. 13-17, the sealing apparatus and sealing structure which concern on Example 4 of this invention are demonstrated.

<Configuration of sealing device and sealing structure>
With reference to FIGS. 13-17, the structure of the sealing device and sealing structure which concern on a present Example is demonstrated. The sealing device 140 according to the present embodiment is mounted in an annular groove 610 provided on the outer periphery of the shaft 600, and rotates relative to the shaft 600 and the housing 700 (the inner periphery of the shaft hole through which the shaft 600 in the housing 700 is inserted. The annular gap between the first and second surfaces is sealed. As a result, the sealing device 140 maintains the fluid pressure in the region to be sealed configured so that the fluid pressure (hydraulic pressure in this embodiment) changes. Here, in this embodiment, the fluid pressure in the right region in FIGS. 13 and 14 is configured to change, and the sealing device 140 serves to maintain the fluid pressure in the right seal region in the drawings. Is responsible. When the automobile engine is stopped, the fluid pressure in the seal target area is low and no load is applied. When the engine is started, the fluid pressure in the seal target area increases.

  The shaft 600 includes a shaft main body 600A and an annular member 600B fixed to the shaft main body 600A in order to make the sealing device 140 easy to attach and detach. A tapered surface 611 whose diameter increases from the low pressure side (L) to the high pressure side (H) is formed on the side wall surface on the high pressure side (H) in the annular groove 610 provided on the outer periphery of the shaft 600. Further, a step 612 is provided on the side wall surface of the annular groove 610 on the low pressure side (L), and a tapered surface 613 is formed on the inner peripheral side of the step 612 so as to increase in diameter toward the low pressure side (L). Yes.

  The sealing device 140 includes a seal ring 240 made of resin such as polyether ether ketone (PEEK), a sliding ring 340 made of a rigid body such as a resin material or a metal material, and the sliding ring 340 facing the high pressure side (H). And a pressing member 440 that presses.

  The seal ring 240 includes a joint portion 240c at one place in the circumferential direction. The joint portion 240c according to the present embodiment employs a so-called special step cut that is cut in a step shape when viewed from either the outer peripheral surface side or the both side wall surfaces. Since the special step cut is a known technique, a detailed description thereof is omitted, but it has a characteristic of maintaining a stable sealing performance even if the peripheral length of the seal ring 240 is changed due to thermal expansion and contraction. In addition, although the case of the special step cut was shown here as an example of the abutment part 240c, about the abutment part 240c, not only this but a straight cut, a bias cut, a step cut (on the outer peripheral surface side and the inner peripheral surface side) The structure cut | disconnected in the staircase shape etc. can be employ | adopted from any viewpoint.

  Further, in the seal ring 240 according to the present embodiment, in the vicinity excluding the joint portion 240c, the cross-sectional shape cut along the plane passing through the axis is a pentagon as shown in FIG. FIG. 17 is a CC cross-sectional view in FIG. More specifically, the seal ring 240 has a tapered surface 243 that increases in diameter toward the high-pressure side (H) on the inner peripheral side and the high-pressure side (H) except for the vicinity of the joint portion 240c. The taper angle of the taper surface 243 is set to be equal to the taper angle of the high-pressure side (H) taper surface 611 in the annular groove 610.

  The circumferential length of the outer circumferential surface 241 of the seal ring 240 according to the present embodiment is configured to be shorter than the circumferential length of the inner circumferential surface of the shaft hole of the housing 700, and is configured to have no fastening allowance. Therefore, if no external force is applied, the outer peripheral surface 241 of the seal ring 240 does not contact the inner peripheral surface of the shaft hole of the housing 700. However, as will be described later, during use, the outer peripheral surface 241 of the seal ring 210 is in close contact with the inner peripheral surface of the shaft hole of the housing 700.

  The sliding ring 340 is composed of an annular member and has a rotationally symmetric shape. The sliding ring 340 has a tapered surface 342 whose diameter increases toward the low pressure side (L) on the inner peripheral side and the low pressure side (L). The taper angle of the taper surface 342 is set to be equal to the taper angle of the low pressure side (L) taper surface 613 in the annular groove 610.

  The sliding ring 340 is disposed on the low pressure side (L) of the seal ring 240. In use, the high pressure side (H) side wall surface 341 of the sliding ring 340 and the low pressure side (L) side wall surface 242 of the seal ring 240 slide.

  The pressing member 440 is disposed between the low pressure side (L) side wall surface of the annular groove 610 and the sliding ring 340. The pressing member 440 is disposed on the outer peripheral side of the step 612 formed on the side wall surface on the low pressure side (L) in the annular groove 610. The pressing member 440 is not particularly limited as long as the sliding ring 340 can be pressed to the high pressure side (L). For example, a rubber ring made of a rubber-like elastic body or a coil spring can be adopted.

<Mechanism when using sealing device>
In particular, with reference to FIG. 13 and FIG. 14, a mechanism during use of the sealing device 140 according to the present embodiment will be described. FIG. 13 shows an unloaded state in which the engine is stopped and there is no differential pressure between the left and right regions (or almost no differential pressure) via the sealing device 140. FIG. 14 shows a state in which the engine is started and the fluid pressure in the right region is higher than the left region through the sealing device 140.

  In an unloaded state, the seal ring 240 is pressed to the high pressure side (H) by the pressing member 440 via the sliding ring 340, and the tapered surface 243 is in contact with the tapered surface 611 of the annular groove 610. At this time, the low-pressure side (L) side wall surface 242 of the seal ring 240 is pressed against the high-pressure side (H) side wall surface 341 of the sliding ring 340. Accordingly, the seal ring 240 receives a force from the tapered surface 611 of the annular groove 610 toward the outer peripheral side. As a result, the seal ring 240 is deformed in the diameter increasing direction, and the outer peripheral surface 241 of the seal ring 240 is in close contact with the inner peripheral surface of the shaft hole of the housing 700.

  With the above configuration, in the no-load state, the seal portion S1 is formed between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700, and the tapered surface 243 of the seal ring 240 A seal portion S <b> 2 is formed between the tapered surface 611 of the annular groove 610. Thus, in the no-load state, the sealing device 140 forms the two seal portions S1 and S2 to seal the annular gap between the shaft 600 and the housing 700.

  Then, in the state where the engine is started and the differential pressure is generated, the seal ring 240 and the sliding member resist the pressing force by the pressing member 440 by the fluid pressure from the high pressure side (H) as shown in FIG. The ring 340 moves to the low pressure side (L). When the differential pressure becomes equal to or greater than a certain level, the sliding ring 340 comes into a state where the low pressure side taper surface 342 is in close contact with the low pressure side (L) taper surface 613 of the annular groove 610.

The seal ring 240 is maintained in a state of being deformed in the diameter-expanding direction by the fluid pressure from the inner peripheral surface side, and the outer peripheral surface 241 of the seal ring 240 is maintained in close contact with the inner peripheral surface of the shaft hole of the housing 700. . Further, the seal ring 240 is pressed against the sliding ring 340 by the fluid pressure from the high pressure side (H). Thereby, the state where the low pressure side (L) side wall surface 242 of the seal ring 240 and the high pressure side (H) side wall surface 341 of the sliding ring 340 are in contact with each other is maintained. Here, the contact area between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700 is the low pressure side (L) in the seal ring 240.
Is set to be sufficiently larger than the contact area between the side wall surface 242 and the high-pressure side (H) side wall surface 341 of the sliding ring 340. Therefore, while the shaft 600 and the housing 700 are relatively rotated, the space between the low pressure side (L) side wall surface 242 of the seal ring 240 and the high pressure side (H) side wall surface 341 of the sliding ring 340 is between. Slide on. Note that there is no sliding between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700.

  With the above configuration, in a state where a differential pressure is generated (high pressure state), the low pressure side (L) of the seal ring 240 is between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700. Between the side wall surface 242 and the high pressure side (H) side wall surface 341 of the sliding ring 340, and the low pressure side (L) tapered surface 342 of the sliding ring 340 and the low pressure side (L) taper of the annular groove 610. Seal portions S1, S2, and S3 are formed between the surface 613 and the surface 613, respectively. However, when the pressing member 440 is a rubber ring, seal portions are respectively provided between the pressing member 440 and the sliding ring 340 and between the pressing member 440 and the side wall surface on the low pressure side (L) of the annular groove 610. It can also be formed. Therefore, in this case, it is not necessary to form a seal portion between the low pressure side (L) tapered surface 342 of the sliding ring 340 and the low pressure side (L) tapered surface 613 of the annular groove 610.

<Excellent points of sealing device and sealing structure according to this embodiment>
According to this embodiment, the seal ring 240 is pressed to the high pressure side (H) by the pressing member 440 via the sliding ring 340 and receives a force from the tapered surface 611 of the annular groove 610 toward the outer peripheral side. As a result, the seal ring 240 is deformed in the diameter increasing direction, and the outer peripheral surface 241 of the seal ring 240 is in close contact with the inner peripheral surface of the shaft hole of the housing 700. Therefore, even when fluid pressure is not applied (no differential pressure is generated) or fluid pressure is hardly applied (almost no differential pressure is generated), the seal ring 240 remains in the shaft hole of the housing 700. It will be in the state which contact | connected the inner peripheral surface and the sealing function will be exhibited. Therefore, the fluid pressure can be maintained immediately after the fluid pressure in the seal target region starts to increase. That is, in an engine having an idling stop function, the hydraulic pressure can be maintained immediately after the hydraulic pressure on the seal target region side is increased by starting the engine when the accelerator is depressed from the engine stopped state.

  Further, when the seal ring 240 is separated from the tapered surface 611 of the annular groove 610 against the pressing force by the pressing member 440 due to the fluid pressure on the high pressure side (H), the seal ring 240 is Seal portions are formed between the outer peripheral surface 241 and the inner peripheral surface of the shaft hole, and between the seal ring 240 and the sliding ring 340. That is, when focusing only on the seal ring 240, the sealing mechanism is the same as that of a general seal ring. Thereby, a sliding torque can be reduced equivalent to the conventional seal ring which reduced the sliding torque.

  Thus, in the case of the seal ring according to the conventional example, by adopting a configuration that reduces the sliding torque, the sealing function was not exhibited in a state where the fluid pressure was not acting, According to the sealing device 140 according to the present embodiment, the sealing function can be exhibited even in the state where the fluid pressure is not applied although the configuration for reducing the sliding torque is adopted.

(Example 5)
18 and 19 show a fifth embodiment of the present invention. In the present embodiment, only the configuration of the annular groove and the sliding ring is different from that of the fourth embodiment. Since other configurations and operations are the same as those in the fourth embodiment, the same components are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

  Also in the present embodiment, the shaft 600 includes a shaft main body 600A and an annular member 600B fixed to the shaft main body 600A in order to make the sealing device 150 easy to attach and detach. Further, a tapered surface 611 having a diameter increasing from the low pressure side (L) toward the high pressure side (H) is formed on the side wall surface on the high pressure side (H) in the annular groove 610 provided on the outer periphery of the shaft 600. . A step 612 is provided on the side wall surface of the annular groove 610 on the low pressure side (L). In the case of the present embodiment, unlike the case of the fourth embodiment, the tapered surface is not formed on the inner peripheral side of the step 612, and the inner peripheral side of the step 612 is configured by a flat surface.

  Also in the sealing device 150 according to the present embodiment, the sealing ring 240 made of resin such as polyetheretherketone (PEEK), the sliding ring 350 made of a rigid body such as a resin material or a metal material, and the sliding ring 350 have a high pressure. And a pressing member 440 that presses toward the side (H). Since the seal ring 240 and the pressing member 440 have the same configuration as that of the fourth embodiment, description thereof is omitted.

  Similarly to the case of the fourth embodiment, the sliding ring 350 according to the present embodiment is also formed of an annular member and has a rotationally symmetric shape. The sliding ring 350 according to the present embodiment is formed of flat surfaces on both side walls, and no tapered surface is provided as in the case of the fourth embodiment.

  The sliding ring 350 is disposed on the low pressure side (L) of the seal ring 240. In use, the high pressure side (H) side wall surface 351 of the sliding ring 350 and the low pressure side (L) side wall surface 242 of the seal ring 240 slide.

  Here, FIG. 18 shows an unloaded state in which the engine is stopped and there is no differential pressure in the left and right regions (or almost no differential pressure) via the sealing device 150. FIG. 19 shows a state in which the engine is started and the fluid pressure in the right region is higher than the left region through the sealing device 150.

  In the no-load state, the seal ring 240 is pressed to the high pressure side (H) by the pressing member 440 via the sliding ring 350, and the tapered surface 243 is in contact with the tapered surface 611 of the annular groove 610. At this time, the low pressure side (L) side wall surface 242 of the seal ring 240 is pressed against the high pressure side (H) side wall surface 351 of the sliding ring 350. Accordingly, the seal ring 240 receives a force from the tapered surface 611 of the annular groove 610 toward the outer peripheral side. As a result, the seal ring 240 is deformed in the diameter increasing direction, and the outer peripheral surface 241 of the seal ring 240 is in close contact with the inner peripheral surface of the shaft hole of the housing 700.

  With the above configuration, in the no-load state, the seal portion S1 is formed between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700, and the tapered surface 243 of the seal ring 240 A seal portion S <b> 2 is formed between the tapered surface 611 of the annular groove 610. Thus, in the no-load state, the sealing device 150 forms the two seal portions S1 and S2 to seal the annular gap between the shaft 600 and the housing 700.

  Then, in the state where the engine is started and the differential pressure is generated, the seal ring 240 and the sliding member resist the pressing force by the pressing member 440 by the fluid pressure from the high pressure side (H) as shown in FIG. The ring 350 moves to the low pressure side (L). When the differential pressure becomes a certain level or more, the sliding ring 350 comes into a state where the low-pressure side wall surface 352 is in close contact with the low-pressure side (L) side wall surface 614 of the annular groove 610.

The seal ring 240 is maintained in a state of being deformed in the diameter-expanding direction by the fluid pressure from the inner peripheral surface side, and the outer peripheral surface 241 of the seal ring 240 is maintained in close contact with the inner peripheral surface of the shaft hole of the housing 700. . The seal ring 240 is pressed against the sliding ring 350 by the fluid pressure from the high pressure side (H). Thereby, the state where the low pressure side (L) side wall surface 242 of the seal ring 240 and the high pressure side (H) side wall surface 351 of the sliding ring 350 are in contact with each other is maintained. Here, the contact area between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700 is such that the side wall surface 242 on the low pressure side (L) of the seal ring 240 and the high pressure side of the sliding ring 350 ( H) is set to be sufficiently larger than the contact area with the side wall surface 351. Therefore, while the shaft 600 and the housing 700 are relatively rotated, the low pressure side (L) side wall surface 242 of the seal ring 240 and the high pressure side (H) side wall surface 351 of the sliding ring 350 are between. Slide on. Note that there is no sliding between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700.

  With the above configuration, in a state where a differential pressure is generated (high pressure state), the low pressure side (L) of the seal ring 240 is between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700. Between the side wall surface 242 of the sliding ring 350 and the side wall surface 351 on the high pressure side (H) of the sliding ring 350, and the low pressure side (L) side wall surface 352 of the sliding ring 350 and the low pressure side (L) side of the annular groove 610. Seal portions S1, S2, and S3 are formed with the wall surface 614, respectively. However, when the pressing member 440 is a rubber ring, seal portions are respectively provided between the pressing member 440 and the sliding ring 350 and between the pressing member 440 and the side wall surface on the low pressure side (L) of the annular groove 610. It can also be formed. Therefore, in this case, it is not necessary to form a seal portion between the low pressure side (L) side wall surface 352 of the sliding ring 350 and the low pressure side (L) side wall surface 614 of the annular groove 610.

  As described above, also in the sealing device 150 according to the present embodiment, it is possible to obtain the same effect as in the case of the fourth embodiment.

(Example 6)
20 and 21 show Embodiment 6 of the present invention. In the present embodiment, only the configuration of the annular groove, the sliding ring, and the pressing member is different from that of the fourth embodiment. Since other configurations and operations are the same as those in the fourth embodiment, the same components are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

  Also in the present embodiment, the shaft 600 includes a shaft main body 600A and an annular member 600B fixed to the shaft main body 600A in order to make the sealing device 160 easy to attach and detach. Further, a tapered surface 611 having a diameter increasing from the low pressure side (L) toward the high pressure side (H) is formed on the side wall surface on the high pressure side (H) in the annular groove 610 provided on the outer periphery of the shaft 600. . In this embodiment, unlike the fourth embodiment, no step is provided on the low pressure side (L) of the annular groove 610.

  Also in the sealing device 160 according to the present embodiment, the sealing ring 240 made of resin such as polyetheretherketone (PEEK), the sliding ring 350 made of a rigid body such as a resin material or a metal material, and the sliding ring 350 are high pressure. And a pressing member 460 that presses toward the side (H). Since the seal ring 240 has the same configuration as that of the fourth embodiment, the description thereof is omitted.

  Similarly to the case of the fourth embodiment, the sliding ring 350 according to the present embodiment is also formed of an annular member and has a rotationally symmetric shape. The sliding ring 350 according to the present embodiment is formed of flat surfaces on both side walls, and no tapered surface is provided as in the case of the fourth embodiment. The sliding ring 350 is disposed on the low pressure side (L) of the seal ring 240. In use, the high pressure side (H) side wall surface 351 of the sliding ring 350 and the low pressure side (L) side wall surface 242 of the seal ring 240 slide.

  And the pressing member 460 which concerns on a present Example is comprised by the cylindrical rubber ring.

  Here, FIG. 20 shows a state in which the engine is stopped and there is no differential pressure in the left and right regions (or almost no differential pressure) via the sealing device 160 and there is no load. FIG. 21 shows a state in which the engine is started and the fluid pressure in the right region is higher than that in the left region through the sealing device 160.

  In the unloaded state, the seal ring 240 is pressed to the high pressure side (H) by the pressing member 460 via the sliding ring 350, and the tapered surface 243 is in contact with the tapered surface 611 of the annular groove 610. At this time, the low pressure side (L) side wall surface 242 of the seal ring 240 is pressed against the high pressure side (H) side wall surface 351 of the sliding ring 350. Accordingly, the seal ring 240 receives a force from the tapered surface 611 of the annular groove 610 toward the outer peripheral side. As a result, the seal ring 240 is deformed in the diameter increasing direction, and the outer peripheral surface 241 of the seal ring 240 is in close contact with the inner peripheral surface of the shaft hole of the housing 700.

  With the above configuration, in the no-load state, the seal portion S1 is formed between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700, and the tapered surface 243 of the seal ring 240 A seal portion S <b> 2 is formed between the tapered surface 611 of the annular groove 610. Thus, in the no-load state, the sealing device 160 forms the two seal portions S1 and S2 to seal the annular gap between the shaft 600 and the housing 700.

  Then, in the state where the engine is started and the differential pressure is generated, the seal ring 240 and the sliding member are opposed to the pressing force by the pressing member 460 by the fluid pressure from the high pressure side (H) as shown in FIG. The ring 350 moves to the low pressure side (L). At this time, the sliding ring 350 is in a state where the low-pressure side (L) side wall surface 352 is in close contact with the high-pressure side (H) side wall surface 461 of the pressing member 460. Further, the low pressure side (L) side wall surface 462 of the pressing member 460 is kept in close contact with the low pressure side (L) side wall surface of the annular groove 610.

  The seal ring 240 is maintained in a state of being deformed in the diameter-expanding direction by the fluid pressure from the inner peripheral surface side, and the outer peripheral surface 241 of the seal ring 240 is maintained in close contact with the inner peripheral surface of the shaft hole of the housing 700. . The seal ring 240 is pressed against the sliding ring 350 by the fluid pressure from the high pressure side (H). Thereby, the state where the low pressure side (L) side wall surface 242 of the seal ring 240 and the high pressure side (H) side wall surface 351 of the sliding ring 350 are in contact with each other is maintained. Here, the contact area between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700 is such that the side wall surface 242 on the low pressure side (L) of the seal ring 240 and the high pressure side of the sliding ring 350 ( H) is set to be sufficiently larger than the contact area with the side wall surface 351. Therefore, while the shaft 600 and the housing 700 are relatively rotated, the low pressure side (L) side wall surface 242 of the seal ring 240 and the high pressure side (H) side wall surface 351 of the sliding ring 350 are between. Slide on. Note that there is no sliding between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700.

  With the above configuration, in a state where a differential pressure is generated (high pressure state), the low pressure side (L) of the seal ring 240 is between the outer peripheral surface 241 of the seal ring 240 and the inner peripheral surface of the shaft hole of the housing 700. Between the side wall surface 242 and the high pressure side (H) side wall surface 351 of the sliding ring 350, the low pressure side (L) side wall surface 352 of the sliding ring 350, and the high pressure side (H) side wall surface of the pressing member 460. Seal portions S1, S2, S3, S4 are formed between the low pressure side (L) side wall surface 462 of the pressing member 460 and the low pressure side (L) side wall surface of the annular groove 610, respectively. A seal portion may be further formed between the inner peripheral surface of the pressing member 460 and the groove bottom surface of the annular groove 610.

  As described above, also in the sealing device 160 according to the present embodiment, it is possible to obtain the same effect as in the case of the fourth embodiment.

(Other)
The sealing device shown in each embodiment described above is applicable even when the shaft 600 and the housing 700 rotate relatively and the shaft 600 and the housing 700 relatively reciprocate.

110, 120, 130, 140, 150, 160 Sealing device 210, 220, 240 Seal ring 210c, 220c, 240c Auxiliary part 211, 221, 241 Outer peripheral surface 212, 222, 242 Side wall surface 213, 214 Tapered surface 215, 216 End Edges 223, 224 Recessed portions 225, 226 End edges 243 Tapered surfaces 310, 330, 340, 350 Sliding rings 311, 331, 341, 351, 352 Side wall surfaces 312 Tapered surfaces 313, 333 Annular convex portions 313a, 333a Tip surface 342 Tapered Surface 410, 440, 460 Pressing member 461, 462 Side wall surface 600 Shaft 600A Shaft body 600B Ring member 610 Ring groove 611 Tapered surface 612 Step 613 Tapered surface 614 Side wall surface 700 Housing

Claims (6)

An annular groove provided on the outer periphery of the shaft, and mounted on the annular groove having a tapered surface whose diameter increases from the low pressure side toward the high pressure side on the side wall surface on the high pressure side, and the shaft rotating relatively A sealing device that seals an annular gap between a housing and maintains fluid pressure in a region to be sealed configured to change fluid pressure,
A resin seal ring that is in close contact with the inner peripheral surface of the shaft hole through which the shaft of the housing is inserted;
A sliding ring that is disposed on the low pressure side of the seal ring and slides against a side wall surface of the seal ring;
A pressing member that presses the sliding ring toward the high-pressure side;
With
In a state where the seal ring is pressed to the high pressure side via the sliding ring by the pressing member and the inner peripheral side of the seal ring is in contact with the tapered surface of the annular groove, the seal ring and the tapered surface And between the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole,
In a state where the seal ring is separated from the tapered surface of the annular groove against the pressing force by the pressing member due to the fluid pressure on the high pressure side, at least the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole And a seal part formed between the seal ring and the sliding ring.   With the fluid pressure on the high pressure side, the seal ring is separated from the tapered surface of the annular groove against the pressing force by the pressing member, and further, the sliding ring and the side wall surface on the low pressure side in the annular groove The sealing device according to claim 1, wherein a seal portion is formed between the two. The pressing member is a rubber ring made of a rubber-like elastic body,
In a state where the seal ring is separated from the tapered surface of the annular groove against the pressing force by the pressing member due to the fluid pressure on the high pressure side, and further between the sliding ring and the rubber ring, and the rubber The sealing device according to claim 1, wherein a seal portion is formed between a ring and a low-pressure side wall surface of the annular groove. A shaft provided on the outer periphery with an annular groove having a tapered surface expanding from the low pressure side to the high pressure side on the side wall surface on the high pressure side;
A housing having a shaft hole through which the shaft is inserted;
A sealing device that is mounted in the annular groove and seals the annular gap between the relatively rotating shaft and the housing, and holds the fluid pressure in the region to be sealed configured to change the fluid pressure; A sealing structure comprising:
The sealing device includes:
A resin seal ring that is in close contact with the inner peripheral surface of the shaft hole;
A sliding ring that is disposed on the low pressure side of the seal ring and slides against a side wall surface of the seal ring;
A pressing member that presses the sliding ring toward the high-pressure side;
With
In a state where the seal ring is pressed to the high pressure side via the sliding ring by the pressing member and the inner peripheral side of the seal ring is in contact with the tapered surface of the annular groove, the seal ring and the tapered surface And between the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole,
In a state where the seal ring is separated from the tapered surface of the annular groove against the pressing force by the pressing member due to the fluid pressure on the high pressure side, at least the outer peripheral surface of the seal ring and the inner peripheral surface of the shaft hole And a seal portion formed between the seal ring and the sliding ring.   With the fluid pressure on the high pressure side, the seal ring is separated from the tapered surface of the annular groove against the pressing force by the pressing member, and further, the sliding ring and the side wall surface on the low pressure side in the annular groove The sealing structure according to claim 4, wherein a seal portion is formed between the two. The pressing member is a rubber ring made of a rubber-like elastic body,
In a state where the seal ring is separated from the tapered surface of the annular groove against the pressing force by the pressing member due to the fluid pressure on the high pressure side, and further between the sliding ring and the rubber ring, and the rubber The sealing structure according to claim 4, wherein a seal portion is formed between a ring and a low-pressure side wall surface of the annular groove.

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