JP2021162135A - Sealing device - Google Patents

Abstract

To reduce friction between a seal member and a shaft member in an environment in which the shaft member rotates at high speed.SOLUTION: A sealing device 100 seals an annular gap G between an outer peripheral surface F1 of a shaft member 11 and an inner peripheral surface F2 of a shaft hole H into which the shaft member 11 is inserted. A seal member 20 is a plate-like annular member including a first surface S1 and a second surface S2 opposite to the first surface S1 and curves so that a contact area Q at the inner periphery side of the first surface S1 contacts with the outer peripheral surface F1 of the shaft member 11 in a use state. A plate spring 30 is a plate-like annular member facing the second surface S2 of the seal member 20 and presses an inner periphery side portion of the seal member 20 against the outer peripheral surface F1 of the shaft member 11 in the use state. A support medium 40 supports outer periphery side portions of the seal member 20 and the plate spring 30. In the contact area Q, an oil retaining groove 22 is formed along a circumferential direction of the seal member 20.SELECTED DRAWING: Figure 1

Description

The present invention relates to a technique for sealing a gap around a shaft member.

Conventionally, a sealing device for sealing an annular gap formed between an outer peripheral surface of a shaft member and an inner peripheral surface of a shaft hole into which the shaft member is inserted has been proposed. For example, in Patent Document 1 and Patent Document 2, a sealing structure in which a plate-shaped and annular sealing member made of a resin material such as PTFE (polytetrafluoroethylene) is brought into contact with the outer peripheral surface of the shaft member in a curved state is sealed. The device is disclosed.

Japanese Unexamined Patent Publication No. 2015-203491 International Publication No. 2019/073808

In an environment in which the shaft member rotates at a high speed, friction between the seal member and the shaft member increases as compared with an environment in which the shaft member rotates at a low speed. Therefore, there is a problem that wear of the seal member is likely to occur. In consideration of the above circumstances, an object of the present invention is to reduce friction between the shaft member and the shaft member in an environment where the shaft member rotates at high speed.

The sealing device according to one aspect of the present invention is a sealing device that seals an annular gap between the outer peripheral surface of the shaft member and the inner peripheral surface of the shaft hole into which the shaft member is inserted. A plate-shaped and annular sealing member including a surface and a second surface opposite to the first surface, and in a used state, a contact region on the inner peripheral side of the first surface is on the outer peripheral surface of the shaft member. A seal member that is curved so as to come into contact with the seal member, and a plate-shaped and annular leaf spring that faces the second surface of the seal member. A leaf spring that presses against the outer peripheral surface of the seal member and an annular support that supports the seal member and the outer peripheral side portion of the leaf spring are provided, and oil is retained in the contact region along the circumferential direction of the seal member. A groove is formed.

In a preferred embodiment of the present invention, the depth of the oil holding groove differs depending on the position in the circumferential direction. Specifically, the oil holding groove extends in the circumferential direction over the first end and the second end, and the depth of the oil holding groove decreases from the central portion in the circumferential direction to the first end. Moreover, it decreases from the central portion to the second end. For example, the bottom surface of the oil holding groove is a flat surface or a curved surface in which the depth of the oil holding groove changes continuously along the circumferential direction, or the depth of the oil holding groove is stepwise along the circumferential direction. It is a changing staircase surface. Further, in a specific aspect of the present invention, the width of the oil holding groove decreases from the central portion to the first end, and decreases from the central portion to the second end.

In a preferred embodiment of the present invention, the sealing member includes a side wall portion located between the oil holding groove and the inner peripheral surface of the sealing member, and the side wall portion is supplied so as to communicate with the oil holding groove. A road is formed.

In a preferred embodiment of the present invention, a plurality of oil holding grooves including the oil holding groove are formed in the contact region, and the plurality of oil holding grooves are arranged along the inner peripheral edge of the sealing member. In a more preferred embodiment, the sealing member includes a side wall portion located between each of the plurality of oil holding grooves and an inner peripheral surface of the sealing member, and the side wall portion includes the plurality of oil holding grooves. A plurality of supply paths communicating with each other are formed, and the leaf spring includes a plurality of spring portions corresponding to the plurality of oil holding grooves, and each tip of the plurality of spring portions corresponds to the spring portion. It overlaps with the supply path communicating with the oil holding groove.

According to the present invention, friction with the shaft member can be reduced in an environment where the shaft member rotates at high speed.

It is sectional drawing of the sealing apparatus of 1st Embodiment in a use state. It is a top view of the sealing device. It is a bottom view of a sealing device. FIG. 2 is a cross-sectional view taken along the line aa in FIG. It is a top view of a leaf spring. It is a top view which shows the relationship between each spring part of a leaf spring, and each groove part of a seal member. It is sectional drawing of bb line in FIG. It is sectional drawing of the oil holding groove in 2nd Embodiment. It is sectional drawing of the oil holding groove in 3rd Embodiment. It is a top view of the groove part in 4th Embodiment. It is a top view of the seal member in the modification. It is a top view of the oil holding groove in the modification. It is a top view of the oil holding groove in the modification. It is sectional drawing of the oil holding groove in the modification.

A preferred embodiment of the present invention will be described below with reference to the drawings. The dimensions and scale of each element in each drawing are appropriately different from the actual product.

A: First Embodiment FIG. 1 is a cross-sectional view of a sealing device 100 according to the first embodiment of the present invention. The state in which the sealing device 100 is used is illustrated in FIG. The sealing device 100 is used to seal the gap G between the shaft member 11 and the housing 12 in an exhaust gas system such as EGR (Exhaust Gas Recirculation).

As illustrated in FIG. 1, the shaft member 11 is a columnar structure. A shaft hole H through which the shaft member 11 is inserted is formed in the housing 12. The sealing device 100 is an annular structure for sealing an annular gap G formed between the outer peripheral surface F1 of the shaft member 11 and the inner peripheral surface F2 of the shaft hole H.

The shaft member 11 moves relative to the housing 12. A typical example of the relative movement of the shaft member 11 is the rotation of the shaft member 11. However, the reciprocation of the shaft member 11 or the swing of the shaft member 11 along the axial direction is also included in the concept of the relative movement of the shaft member 11.

In the following description, the circumferential direction of a virtual circle having an arbitrary radius centered on the central axis C of the sealing device 100 is referred to as "circumferential direction", and the radial direction of the virtual circle is referred to as "diameter direction". write. Further, one direction along the central axis C is described as "X1 direction", and the direction opposite to X1 is described as "X2 direction". In FIG. 1, the space R located in the X2 direction with respect to the sealing device 100 is a space in which a fluid (gas or liquid) to be sealed by the sealing device 100 exists. The space R located in the X2 direction across the sealing device 100 has a higher pressure than the space located in the X1 direction across the sealing device 100. It may be expressed that the high pressure side corresponds to the X2 direction when viewed from the sealing device 100 and the low pressure side corresponds to the X1 direction when viewed from the sealing device 100 in the used state.

FIG. 2 is a plan view of the sealing device 100, and FIG. 3 is a bottom view of the sealing device 100. FIG. 2 is a plan view of the sealing device 100 from a viewpoint located in the X2 direction, and FIG. 3 is a plan view of the sealing device 100 from a viewpoint located in the X1 direction. Further, FIG. 4 is a cross-sectional view taken along the line aa in FIG. 2 to 4 show a sealing device 100 that is not installed in the gap G (hereinafter referred to as “non-used state”). As illustrated in FIGS. 2 to 4, the sealing device 100 includes a sealing member 20, a leaf spring 30, and a support 40.

The seal member 20 is an annular structure in which a circular opening centered on the central axis C is formed. The inner diameter of the seal member 20 is smaller than the outer diameter of the shaft member 11. As illustrated in FIG. 4, the seal member 20 is a plate-shaped elastic member including the first surface S1 and the second surface S2. The first surface S1 and the second surface S2 are plate surfaces on opposite sides to each other. The seal member 20 is formed of a resin material such as PTFE (polytetrafluoroethylene) to a plate thickness of, for example, 0.3 or more and 0.6 mm or less. Compared with elastic materials such as rubber, PTFE has the advantages of being excellent in heat resistance and pressure resistance and having less sliding wear.

The leaf spring 30 is a plate-shaped structure formed in an annular shape. The leaf spring 30 is an elastic member made of a metal material such as stainless steel (SUS). The plate thickness of the leaf spring 30 is, for example, 0.05 mm or more and 0.1 mm or less. That is, the leaf spring 30 is thinner than the seal member 20. As illustrated in FIG. 4, the leaf spring 30 is installed concentrically with the seal member 20 in a state of facing the second surface S2. Specifically, the leaf spring 30 is in close contact with the second surface S2 of the seal member 20. The inner diameter of the leaf spring 30 is larger than the inner diameter of the sealing member 20.

FIG. 5 is a plan view of the leaf spring 30. As illustrated in FIG. 5, the leaf spring 30 of the first embodiment includes a plurality of spring portions 31 arranged in the circumferential direction at intervals from each other. The plurality of spring portions 31 are connected to each other on the outer peripheral side of the leaf spring 30.

The leaf spring 30 is also referred to as an annular plate-shaped member in which a plurality of inner slits 32 and a plurality of outer slits 33 are formed. Each inner slit 32 is a linear notch extending in the radial direction from the inner peripheral edge to the outer peripheral edge of the leaf spring 30. Each outer slit 33 is a linear notch extending in the radial direction from the outer peripheral edge to the inner peripheral edge of the leaf spring 30. The inner slit 32 and the outer slit 33 are arranged alternately in the circumferential direction. The portion between the two inner slits 32 adjacent to each other is one spring portion 31. An outer slit 33 is formed in each spring portion 31.

The support 40 of FIG. 4 is an annular structure that supports the seal member 20 and the leaf spring 30. The support 40 of the first embodiment includes a support ring 50 and a fixed ring 60. The seal member 20 and the leaf spring 30 are sandwiched between the support ring 50 and the fixed ring 60.

The support ring 50 includes a tubular portion 51, a first flange-shaped portion 52, and a second flange-shaped portion 53. The tubular portion 51 is a cylindrical portion. The inner diameter of the tubular portion 51 is equivalent to the outer diameter of the seal member 20 and the outer diameter of the leaf spring 30. The first flange-shaped portion 52 is an annular plate-shaped portion of the tubular portion 51 that protrudes inward in the radial direction (center axis C side) from the end portion in the X1 direction. The inner diameter of the first flange-shaped portion 52 is smaller than the outer diameter of the seal member 20 and the outer diameter of the leaf spring 30. The second flange-shaped portion 53 is an annular plate-shaped portion of the tubular portion 51 that protrudes inward in the radial direction from the end portion in the X2 direction. The inner diameter of the second flange-shaped portion 53 is smaller than the outer diameter of the seal member 20 and the outer diameter of the leaf spring 30.

The fixed ring 60 includes a cylindrical portion 61 and a flange-shaped portion 62. The tubular portion 61 is a cylindrical portion. The outer diameter of the tubular portion 61 is equivalent to the inner diameter of the tubular portion 51. The flange-shaped portion 62 is an annular plate-shaped portion of the tubular portion 61 that protrudes inward in the radial direction from the end portion in the X1 direction. The inner diameter of the flange-shaped portion 62 is smaller than the outer diameter of the seal member 20 and the outer diameter of the leaf spring 30.

The fixed ring 60 is fitted to the support ring 50. Specifically, the fixed ring 60 is housed between the first flange-shaped portion 52 and the second flange-shaped portion 53 in a state where the outer peripheral surface of the tubular portion 61 is in contact with the inner peripheral surface of the tubular portion 51. Will be done. In the above state, the outer peripheral side portions of the seal member 20 and the leaf spring 30 are sandwiched between the first flange-shaped portion 52 of the support ring 50 and the flange-shaped portion 62 of the fixed ring 60.

As illustrated in FIG. 1, in the used state, the outer peripheral surface of the cylindrical portion 51 of the support ring 50 comes into contact with the inner peripheral surface F2 of the shaft hole H. Further, the shaft member 11 is inserted into the opening of the seal member 20 along the X2 direction. As described above, since the inner diameter of the seal member 20 is smaller than the outer diameter of the shaft member 11, the inner peripheral side portion of the seal member 20 is curved in the X2 direction in the used state. Specifically, the seal member 20 is curved so that the first surface S1 of the seal member 20 expands and the second surface S2 contracts. When the seal member 20 is curved as described above, in the used state, the inner peripheral side region (hereinafter referred to as “contact region”) Q of the first surface S1 of the seal member 20 is the outer peripheral surface F1 of the shaft member 11. Contact. As illustrated in FIGS. 1 and 3, the contact region Q is an annular region of the first surface S1 extending from the inner peripheral edge of the seal member 20 to a part in the radial direction.

As illustrated in FIG. 1, in the used state, each spring portion 31 of the leaf spring 30 is curved along the second surface S2 of the seal member 20. In the used state, each spring portion 31 presses the inner peripheral side portion of the seal member 20 against the outer peripheral surface F1 of the shaft member 11 by an elastic restoring force. With the above configuration, the inner peripheral side portion of the seal member 20 tightens the shaft member 11. The shaft member 11 is rotatable with respect to the housing 12 in a state where the contact region Q of the seal member 20 is in close contact with the outer peripheral surface F1 of the shaft member 11. That is, the seal member 20 slides with respect to the shaft member 11.

FIG. 1 also shows an enlarged view of the contact region Q of the seal member 20. As illustrated in FIGS. 1 and 3, a plurality of groove portions 21 are formed in the contact region Q of the first surface S1 at intervals from each other. Each of the plurality of groove portions 21 is a recess recessed with respect to the first surface S1. As illustrated in FIG. 3, the plurality of groove portions 21 are arranged in the circumferential direction along the inner peripheral edge of the seal member 20 in the contact region Q. Each groove 21 is formed on the first surface S1 by, for example, a processing technique such as cutting or a forming technique such as press molding.

As illustrated in FIG. 1, each groove portion 21 of the first embodiment is formed in a planar shape including an oil holding groove 22 and a supply path 23. The oil holding groove 22 is a flow path for holding the lubricating oil. The supply path 23 is a flow path for supplying lubricating oil to the oil holding groove 22.

The oil holding groove 22 is a flow path extending in the circumferential direction over the first end E1 and the second end E2. Specifically, the oil holding groove 22 is formed in a rectangular shape in which the flow path width is kept constant over the first end E1 and the second end E2. The supply path 23 is a flow path that connects the oil holding groove 22 and the inner peripheral surface Fa of the seal member 20. One end of the supply path 23 is connected to the central portion M of the oil holding groove 22. The central portion M is a portion of the oil holding groove 22 located at the center between the first end E1 and the second end E2. The other end of the supply path 23 opens into the inner peripheral surface Fa of the seal member 20. The lubricating oil that has entered the supply path 23 from the inner peripheral surface Fa of the seal member 20 is supplied to the oil holding groove 22 via the supply path 23 and then held in the oil holding groove 22. The oil holding groove 22 is also referred to as a space partitioned by a side wall portion 24 along the inner peripheral edge of the seal member 20. The side wall portion 24 is an arc-shaped wall portion located between the oil holding groove 22 and the inner peripheral edge of the seal member 20. The supply path 23 is a notch formed in the side wall portion 24.

FIG. 6 is a plan view illustrating the relationship between each groove portion 21 of the seal member 20 and each spring portion 31 of the leaf spring 30. As illustrated in FIG. 6, each of the plurality of groove portions 21 and each of the plurality of spring portions 31 have a one-to-one correspondence. The period of the plurality of groove portions 21 in the circumferential direction and the period of the plurality of spring portions 31 in the circumferential direction are equal to each other. As illustrated in FIG. 6, in the non-use state, each of the plurality of groove portions 21 and each of the plurality of spring portions 31 overlap each other in a plan view along the direction of the central axis C. Specifically, the tip of each spring portion 31 overlaps the supply path 23 of the one groove portion 21 corresponding to the spring portion 31 in a plan view. The tip of each spring portion 31 does not overlap the oil holding groove 22 of the groove portions 21. However, the correspondence relationship between each groove portion 21 and each spring portion 31 is not limited to the above examples. For example, a configuration in which the period of the plurality of groove portions 21 is an integral multiple of the period of the plurality of spring portions 31 or a configuration in which the period of the plurality of spring portions 31 is an integral multiple of the period of the plurality of groove portions 21 is also assumed. Further, the plurality of groove portions 21 and the plurality of spring portions 31 may be arranged in the circumferential direction at different cycles.

FIG. 7 is a cross-sectional view taken along the line bb in FIG. That is, a cross section of the oil holding groove 22 along the longitudinal direction is shown in FIG. As illustrated in FIG. 7, the depth of the oil holding groove 22 changes depending on the position in the circumferential direction. Specifically, the bottom surface of the first portion P1 between the central portion M and the first end E1 of the oil holding groove 22 is deeper at a point near the central portion M than at a point near the first end E1. It is a plane that is inclined with respect to the first surface S1 so as to be. Assuming that the outer peripheral surface F1 advances in the Y1 direction with respect to the first surface S1 due to the rotation of the shaft member 11, the first portion P1 is also referred to as a flow path whose depth decreases toward a point downstream in the Y1 direction. Will be done.

On the other hand, the bottom surface of the second portion P2 between the central portion M and the second end E2 of the oil holding groove 22 is such that the point near the central portion M is deeper than the point near the second end E2. It is a plane inclined with respect to the first surface S1. Assuming that the outer peripheral surface F1 travels in the Y2 direction opposite to the Y1 direction with respect to the first surface S1 due to the rotation of the shaft member 11, the depth of the second portion P2 becomes deeper toward a point downstream in the Y2 direction. It is also called a decreasing flow path. As understood from the above description, the bottom surface of the oil holding groove 22 in the first embodiment is a tapered surface whose depth increases linearly from each of the first end E1 and the second end E2 to the central portion M. ..

As described above, in the first embodiment, the oil holding groove 22 along the circumferential direction is formed in the contact region Q of the first surface S1 of the seal member 20 in contact with the outer peripheral surface F1 of the shaft member 11. .. The dynamic pressure generated in the lubricating oil in the oil holding groove 22 acts on the shaft member 11, so that the friction between the first surface S1 of the seal member 20 and the outer peripheral surface F1 of the shaft member 11 is reduced. Therefore, the sealing device 100 can be suitably used even in a high-pressure environment in which the shaft member 11 rotates at high speed. In the first embodiment, in particular, since a plurality of oil holding grooves 22 along the circumferential direction are formed in the contact region Q, the effect of reducing the friction between the shaft member 11 and the seal member 20 is exceptional. It is remarkable.

Further, since the depth of the oil holding groove 22 differs depending on the position in the circumferential direction of the oil holding groove 22, dynamic pressure is generated due to the wedge effect of the lubricating oil held in the oil holding groove 22. Therefore, the above-mentioned effect of reducing the friction between the shaft member 11 and the seal member 20 is particularly remarkable. In the first embodiment, in particular, since the depth of the oil holding groove 22 decreases toward both ends (first end E1 and second end E2) in the circumferential direction centered on the central portion M, the shaft member 11 is in the Y1 direction and There is an advantage that the dynamic pressure due to the wedge effect can be used regardless of the rotation in the Y2 direction.

By the way, as described above, the inner peripheral side portion of the seal member 20 is pressed by each spring portion 31. The pressing force acting on the seal member 20 from the spring portion 31 tends to increase locally at the tip of the spring portion 31. Therefore, for example, in a configuration in which the tip of the spring portion 31 overlaps the oil holding groove 22 in the non-used state, the oil holding groove 22 is deformed by being pressed by the spring portion 31 in the used state (for example, the oil holding groove 22 is crushed). , There is a possibility that sufficient dynamic pressure is not generated in the oil holding groove 22. In consideration of the above circumstances, in the first embodiment, as described above, the tip of the spring portion 31 overlaps the supply path 23 of the groove portion 21 in the non-used state. According to the above configuration, since the tip of the spring portion 31 does not overlap the oil holding groove 22, it is suppressed that each oil holding groove 22 is deformed by the pressure from the spring portion 31 in the used state. Therefore, it is possible to generate a sufficient dynamic pressure in the oil holding groove 22 in the used state. Further, in the first embodiment, as understood from FIG. 7, the depth of the supply path 23 is larger than the maximum value of the depth of the oil holding groove 22 (specifically, the depth in the central portion M). .. Therefore, even if the supply path 23 is deformed by the pressing from the spring portion 31, the supply path 23 is not completely blocked. That is, the function of the supply path 23 for supplying the lubricating oil to the oil holding groove 22 is maintained.

B: Second Embodiment FIG. 8 is a cross-sectional view (cross section corresponding to FIG. 7) of the oil holding groove 22 in the second embodiment. As described above, the bottom surface of the oil holding groove 22 of the first embodiment is a flat surface inclined with respect to the first surface S1. As illustrated in FIG. 8, the bottom surface of the oil holding groove 22 in the second embodiment is composed of a curved surface in which the depth of the oil holding groove 22 continuously changes along the circumferential direction. The planar shape of the oil holding groove 22 is the same as that of the first embodiment.

Specifically, the bottom surface of the first portion P1 of the oil holding groove 22 is a curved surface curved so that the point near the central portion M is deeper than the point near the first end E1. Similarly, the bottom surface of the second portion P2 of the oil holding groove 22 is a curved surface curved so that the point near the central portion M is deeper than the vicinity of the second end E2. In the second embodiment, the same effect as in the first embodiment is realized.

C: Third embodiment
FIG. 9 is a cross-sectional view (cross section corresponding to FIG. 7) of the oil holding groove 22 according to the third embodiment. The bottom surface of the oil holding groove 22 in the first embodiment and the second embodiment is a surface (plane or curved surface) whose depth continuously changes along the circumferential direction. The bottom surface of the oil holding groove 22 in the third embodiment is a staircase surface in which the depth of the oil holding groove 22 changes stepwise along the circumferential direction. That is, a plurality of steps are formed on the bottom surface of the oil holding groove 22.

Specifically, on the bottom surface of the first portion P1 of the oil holding groove 22, a plurality of steps are arranged in the circumferential direction so that the point near the central portion M is deeper than the point near the first end E1. It is a staircase surface. Similarly, the bottom surface of the second portion P2 of the oil holding groove 22 is a staircase surface in which a plurality of steps are arranged in the circumferential direction so that the point near the central portion M is deeper than the vicinity of the second end E2. be. The same effect as that of the first embodiment is realized in the third embodiment.

D: Fourth Embodiment FIG. 10 is a plan view of the groove portion 21 in the fourth embodiment. The planar shape of the oil holding groove 22 in the first embodiment is a rectangular shape in which the flow path width is kept constant over the first end E1 and the second end E2. The oil holding groove 22 in the fourth embodiment is formed in a planar shape in which the flow path width changes along the circumferential direction. The flow path width of the oil holding groove 22 is the dimension of the oil holding groove 22 in the direction orthogonal to the longitudinal direction of the oil holding groove 22 in a plan view from the direction perpendicular to the first surface S1.

As illustrated in FIG. 10, the flow path width of the oil holding groove 22 continuously decreases from the central portion M to the first end E1 and continuously decreases from the central portion M to the second end E2. That is, the flow path width Wm at the central portion M is larger than the flow path width We1 at the first end E1 and the flow path width We2 at the second end E2 (Wm> We1, Wm> We2).

The same effect as that of the first embodiment is realized in the fourth embodiment. Further, in the fourth embodiment, since the flow path width of the oil holding groove 22 decreases from the central portion M to the first end E1 or the second end E2, it is compared with the first embodiment in which the flow path width is constant. Therefore, the wedge effect of the lubricating oil held in the oil holding groove 22 is large. Therefore, the above-mentioned effect of reducing the friction between the shaft member 11 and the seal member 20 is particularly remarkable.

The configuration of the second embodiment in which the bottom surface of the oil holding groove 22 is formed of a curved surface and the configuration of the third embodiment in which the bottom surface of the oil holding groove 22 is formed of a staircase surface are also included in the fourth embodiment. It applies in the same way.

E: Deformation example Specific deformation modes added to each of the above-exemplified modes are illustrated below. Two or more embodiments arbitrarily selected from the following examples may be appropriately merged to the extent that they do not contradict each other.

(1) In each of the above-described embodiments, the configuration in which the oil holding groove 22 is partitioned by the side wall portion 24 along the inner peripheral edge of the seal member 20 is illustrated, but the side wall portion 24 and the supply path 23 may be omitted. For example, as illustrated in FIG. 11, a plurality of oil holding grooves 22 may be formed so as to be continuous with the inner peripheral surface Fa of the seal member 20. However, in the configuration in which the side wall portion 24 is omitted, the dynamic pressure generated in the lubricating oil in the oil holding groove 22 is likely to dissipate. According to the configuration including the side wall portion 24 as in each of the above-described embodiments, the lubricating oil is easily held in the oil holding groove 22, so that the dissipation of the dynamic pressure generated in the oil holding groove 22 is suppressed. Therefore, from the viewpoint of reducing the friction between the seal member 20 and the shaft member 11, the configuration in which the side wall portion 24 is formed as illustrated in each of the above-described embodiments is more advantageous than the configuration of FIG.

(2) In each of the above-described embodiments, the first portion P1 from the central portion M to the first end E1 through which the supply path 23 communicates, and the second portion up to the second end E2 on the opposite side of the first end E1. Although the configuration in which the oil holding groove 22 includes P2 is illustrated, the shape of the oil holding groove 22 is not limited to the above examples.

For example, in a configuration in which the shaft member 11 rotates only in one direction in which the outer peripheral surface F1 travels in the Y1 direction with respect to the first surface S1, the oil holding groove 22 to the second portion P2 are omitted as illustrated in FIG. May be done. That is, the oil holding groove 22 is formed in a planar shape extending over the end portion Ea communicating with the supply path 23 and the first end E1 located in the Y1 direction of the end portion Ea. The depth of the oil holding groove 22 increases continuously or stepwise from the first end E1 to the end Ea.

Further, for example, in a configuration in which the shaft member 11 rotates only in one direction in which the outer peripheral surface F1 advances in the Y2 direction with respect to the first surface S1, as illustrated in FIG. 13, the oil holding groove 22 to the first portion P1 May be omitted. That is, the oil holding groove 22 is formed in a planar shape extending over the end portion Ea communicating with the supply path 23 and the second end E2 located in the Y2 direction of the end portion Ea. The depth of the oil holding groove 22 increases continuously or stepwise from the second end E2 to the end Ea.

In any of the configurations of FIGS. 12 and 13, the depth of the oil holding groove 22 decreases toward a point downstream in the direction (Y1, Y2) in which the outer peripheral surface F1 advances with respect to the first surface S1. , Changes continuously or stepwise along the circumferential direction.

(3) In each of the above-described embodiments, the configuration in which the depth of the oil holding groove 22 changes along the circumferential direction is illustrated, but as illustrated in FIG. 14, the depth is maintained constant throughout the circumferential direction. An oil holding groove 22 having a shape to be formed may be formed on the first surface S1. The bottom surface of the oil holding groove 22 in FIG. 14 is a plane parallel to the first surface S1. Even in the oil holding groove 22 having a flat bottom surface as described above, it is possible to generate dynamic pressure in the lubricating oil according to the configuration in which the depth is sufficiently small. However, from the viewpoint of generating dynamic pressure by the wedge effect of the lubricating oil, a configuration in which the depth of the oil holding groove 22 changes along the circumferential direction is preferable as illustrated in each of the above-described forms. It is also assumed that the bottom surface of the oil holding groove 22 includes both a flat surface and a curved surface, or a configuration including both an inclined surface with respect to the first surface S1 and a plane parallel to the first surface S1.

(4) In each of the above-described embodiments, a configuration in which a plurality of groove portions 21 are formed in the contact region Q is illustrated, but the number of groove portions 21 formed in the contact region Q is arbitrary. For example, it is assumed that only one groove 21 is formed in the contact region Q. However, from the viewpoint of reducing the friction between the shaft member 11 and the seal member 20 due to the generation of dynamic pressure, a configuration in which a plurality of groove portions 21 along the circumferential direction of the shaft member 11 are formed in the contact region Q is preferable. be.

100 ... Sealing device, 11 ... Shaft member, 12 ... Housing, H ... Shaft hole, G ... Gap, 20 ... Seal member, 21 ... Groove, 22 ... Oil holding groove, 23 ... Supply path, 24 ... Side wall, 30 ... Leaf spring, 31 ... Spring part, 32 ... Inner slit, 33 ... Outer slit, 40 ... Support, 50 ... Support ring, 51 ... Cylindrical part, 52 ... First flange-shaped part, 53 ... Second flange-shaped part, 60 ... fixed ring, 61 ... tubular part, 62 ... flange-shaped part.

Claims (9)

A sealing device that seals an annular gap between the outer peripheral surface of the shaft member and the inner peripheral surface of the shaft hole into which the shaft member is inserted.
A plate-shaped and annular sealing member including a first surface and a second surface opposite to the first surface, and in a used state, the contact region on the inner peripheral side of the first surface is the outer periphery of the shaft member. A sealing member that curves to contact the surface,
A leaf spring which is a plate-shaped and annular leaf spring facing the second surface of the seal member and presses the inner peripheral side portion of the seal member against the outer peripheral surface of the shaft member in the used state.
The seal member and the annular support for supporting the outer peripheral side portion of the leaf spring are provided.
A sealing device in which an oil holding groove is formed in the contact region along the circumferential direction of the sealing member. The sealing device according to claim 1, wherein the depth of the oil holding groove differs depending on the position in the circumferential direction. The oil holding groove extends in the circumferential direction over the first end and the second end.
The sealing device according to claim 2, wherein the depth of the oil holding groove decreases from the central portion in the circumferential direction to the first end, and decreases from the central portion to the second end. The sealing device according to claim 3, wherein the width of the oil holding groove decreases from the central portion to the first end, and decreases from the central portion to the second end. The sealing device according to any one of claims 2 to 4, wherein the bottom surface of the oil holding groove is a flat surface or a curved surface in which the depth of the oil holding groove continuously changes along the circumferential direction. The sealing device according to any one of claims 2 to 4, wherein the bottom surface of the oil holding groove is a staircase surface in which the depth of the oil holding groove changes stepwise along the circumferential direction. The sealing member includes a side wall portion located between the oil holding groove and the inner peripheral edge of the sealing member.
The sealing device according to any one of claims 1 to 6, wherein a supply path communicating with the oil holding groove is formed on the side wall portion. A plurality of oil holding grooves including the oil holding groove are formed in the contact region.
The sealing device according to any one of claims 1 to 6, wherein the plurality of oil holding grooves are arranged along the inner peripheral edge of the sealing member. The sealing member includes a side wall portion located between each of the plurality of oil holding grooves and the inner peripheral edge of the sealing member.
A plurality of supply paths communicating with the plurality of oil holding grooves are formed in the side wall portion.
The leaf spring includes a plurality of spring portions corresponding to the plurality of oil holding grooves, respectively.
The sealing device according to claim 8, wherein the tip of each of the plurality of spring portions overlaps with the supply path communicating with the oil holding groove corresponding to the spring portion.

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