sealing ring

Abstract

The present application provides a seal ring for sealing an annular gap between a housing and a shaft assembled at a shaft hole thereof, can effectively generate dynamic pressure acting in the direction of a side of one end side of a seal surface of a seal ring body away from an annular groove, and can sufficiently reduce friction torque even under high pressure and high speed rotation. The seal ring includes: a circular ring-shaped seal ring body; a first seal surface formed at the seal ring body and in sliding contact with a side surface of an annular groove of the shaft; a second seal surface formed at the seal ring body and in contact with an inner peripheral surface of the housing; and a plurality of tabs formed at an inner peripheral surface of the seal ring body in a manner of protruding toward a radial inner side. At at least a portion of the tabs on the first seal surface side, an inclined portion (a convex portion (a tapered surface)) is formed toward a circumferential direction of the seal ring body.

Description

Technical Field

[0001] This invention relates to sealing rings, and more particularly to sealing rings used, for example, in automatic transmissions (AT) of automobiles, for sealing lubricating oil in the gap between a shaft and a housing. Background Technology

[0002] For example, multiple sealing rings are used in automatic transmissions (AT) used in automobiles. Figure 19 and Figure 20 The annular sealing ring 100 shown is assembled between the shaft 300 and the housing 200, which move relative to each other in the oil pressure circuit of the transmission, and serves to seal the lubricating oil while sliding.

[0003] like Figure 20 , Figure 21 As shown, the sealing ring 100 is installed in an annular groove 301 formed on the outer peripheral surface 300a of the shaft 300, and seals the annular gap 400 between the housing 200 and the shaft 300 assembled inside it.

[0004] like Figure 19 As shown, at the sealing ring 100, sometimes at multiple locations on the inner circumferential surface 100a side of the sealing ring 100, there are protrusions 101 that protrude radially inward.

[0005] The tab 101 is used to prevent the center of the sealing ring 100 from deviating significantly from the center of the shaft by having its front end contact the bottom surface of the annular groove 301 when the shaft 300 is assembled inside the housing 200.

[0006] As described above, the sealing ring 100 is installed in the annular groove 301 located on the outer circumferential surface 300a of the shaft 300, such as... Figure 21 As shown, the pressure P of the lubricating oil received from the oil supply side (annular gap 400 side) is used to make its outer peripheral surface 100b contact the inner peripheral surface 201 of the housing 200.

[0007] Furthermore, the side 100c of the oil seal side (annular gap 401 side) of the sealing ring 100 slides into contact with the side 301a of the annular groove 301 through the rotation of the shaft 300. This prevents lubricating oil from leaking to the oil seal side.

[0008] The sealing ring 100 has a cross-sectional shape, for example, T-shaped. Thus, the pressure of the lubricating oil wound between the non-sealing surface 100d and the sidewall surface 301a of the annular groove 301 causes a force to act on the sealing surface 100c of the sealing ring 100 in a direction away from the sidewall surface 301a of the annular groove 301. As a result, the sliding friction force generated between the sealing surface 100c and the sidewall surface 301a is reduced, and the frictional torque generated by sliding against the sidewall surface 301a of the annular groove 301 is reduced.

[0009] However, in recent years, with the increasing performance of automatic transmissions and other devices, the operating conditions of sealing rings have become more stringent, requiring further reduction of frictional torque in order to withstand use under higher pressure and high-speed rotation.

[0010] As a sealing ring for solving this problem, Japanese Patent Application Publication No. 2007-107547 discloses such a method. Figure 22 The sealing ring shown.

[0011] The sealing ring 100 includes a sealing surface 100c, which is adjacent to the non-sealing side of the annular groove 301. Figure 21 The sealing ring 100 slides in contact with the side surface 301a of the annular gap 401. Furthermore, the sealing ring 100 includes a non-sealing surface 100d, which is positioned closer to the bottom of the annular groove 301 than the sealing surface 100c, and is configured to form a gap between itself and the side surface 301a of the annular groove 301 on the non-sealing side. Moreover, a recess 110 is continuously formed on the non-sealing surface 100d.

[0012] The recess 110 is a dynamic pressure generating surface that generates dynamic pressure by utilizing the flow of lubricating oil generated at the gap due to the relative rotation between the housing 200 and the shaft 300. The dynamic pressure generated by the recess 110 acts in the direction that moves the sealing ring 100 away from the non-sealing object side (annular gap 401 side) of the annular groove 301.

[0013] That is, multiple recesses 110 are continuously provided along the circumference of the non-sealing surface 100d, and are configured such that the flow path of the lubricating oil gradually narrows from the recesses 110 toward the top of the non-sealing surface 100d. Therefore, the lubricating oil flowing into the narrow flow path generates dynamic pressure between the non-sealing surface 100d and the side surface 301a of the non-sealing object side (annular gap 401 side) of the annular groove 301 according to the so-called wedge effect.

[0014] As a result, the sealing ring 100 is pressed from the non-sealing object side (annular gap 401 side) to the sealing object side (annular gap 400 side), and the surface pressure of the sealing surface 100c decreases.

[0015] However, in the structure of the sealing ring disclosed in Japanese Patent Application Publication No. 2007-107547, since a recess is formed at the non-sealing surface with a narrow radial width, it may not be able to generate the dynamic pressure required for use under high pressure and high speed rotation.

[0016] To address this problem, the inventors conducted in-depth research and development, and discovered that by using multiple protrusions formed on the inner circumferential surface of the sealing ring as dynamic pressure generating surfaces, dynamic pressure can be generated more effectively, reducing frictional torque, thus completing this invention. Summary of the Invention

[0017] The purpose of this invention is to provide a sealing ring for sealing the annular gap between a housing and a shaft assembled inside it, which can effectively generate dynamic pressure in the direction that moves the sealing surface of the sealing ring body away from the oil seal side of the annular groove, and can sufficiently reduce frictional torque even under high pressure and high speed rotation.

[0018] To solve the aforementioned problem, the sealing ring according to the present invention is an annular sealing ring for sealing the gap between a housing and a shaft, characterized in that it comprises at least: an annular sealing ring body; a first sealing surface formed on the sealing ring body and slidingly contacting the side of an annular groove of the shaft; a second sealing surface formed on the sealing ring body and contacting the inner circumferential surface of the housing; and a plurality of protrusions formed on the inner circumferential surface of the sealing ring body in a radially inward manner, for preventing the center of the sealing ring from deviating significantly from the center of the shaft when the assembly is mounted on the housing, wherein at least a portion of the protrusions on the first sealing surface side has an inclined portion formed circumferentially toward the sealing ring body.

[0019] Thus, in this invention, a centering tab is used to prevent the center of the sealing ring from deviating significantly from the center of the shaft when the shaft is assembled onto the housing. At least a portion of the tab on the first sealing surface side has an inclined portion formed circumferentially toward the sealing ring body. Furthermore, the inclined portion serves as a dynamic pressure generating surface, generating dynamic pressure.

[0020] Therefore, for example, compared to the conventional case where a dynamic pressure generating surface is formed only on the non-sealing surface, a greater dynamic pressure can be effectively generated. That is, according to the present invention, the sliding friction force generated at the sliding surface can be reduced, an appropriate oil film can be present at the sliding surface, and the frictional torque can be effectively reduced.

[0021] Preferably, the inclined portion formed at at least a portion of the first sealing surface side of the tab forms a protrusion, the protrusion passing through the axial center of the second sealing surface of the sealing ring body and protruding in a direction away from the width centerline orthogonal to the axial centerline of the sealing ring body.

[0022] Furthermore, preferably, the protrusion formed at the tab includes a circumferentially mountain-shaped conical surface toward the sealing ring body, the conical surface having: a first conical surface, formed of a plane or a curved surface, and inclined away from the width centerline; and a second conical surface, formed of a plane or a curved surface, and inclined from the top of the first conical surface toward the width centerline.

[0023] By utilizing the first conical surface and the second conical surface (a mountain-shaped conical surface along the circumference of the sealing ring body), a wedge-shaped flow path can be formed along the circumference of the sealing ring body, and the conical surface can be used as a dynamic pressure generating surface.

[0024] Furthermore, preferably, the inclined portion formed at least a portion of the first sealing surface side of the tab forms a recess, the recess being recessed along a width centerline approximately orthogonal to the axial centerline of the second sealing surface of the sealing ring body through the axial center of the second sealing surface of the sealing ring body.

[0025] In this case, similar to the case where the inclined portion forms a convex portion, the concave portion can be used as a dynamic pressure generating surface.

[0026] Preferably, the recess formed at the tab includes a circumferentially valley-shaped conical surface toward the sealing ring body, the conical surface having: a first conical surface, formed of a plane or a curved surface, and inclined to approach the width centerline; and a second conical surface, formed of a plane or a curved surface, and inclined to move away from the width centerline from the bottom of the first conical surface.

[0027] By utilizing the first conical surface and the second conical surface (a valley-shaped conical surface along the circumference of the sealing ring body), a wedge-shaped flow path can be formed along the circumference of the sealing ring body, and the conical surface can be used as a dynamic pressure generating surface.

[0028] Furthermore, preferably, the sealing ring includes: a non-sealing surface formed at a position closer to the bottom surface of the annular groove than the first sealing surface, and configured to form a gap between it and the side surface of the annular groove on the oil seal side; and a protrusion formed in the non-sealing surface along the circumference of the sealing ring body, the protrusion having: a third conical surface continuously formed from the first conical surface formed at the protrusion, and inclinedly formed away from the width centerline; and a fourth conical surface continuously formed from the second conical surface formed at the protrusion, and inclinedly formed from the top of the third conical surface approaching the width centerline.

[0029] In this way, by setting the convex portion of the non-sealing surface as a third and fourth conical surface that are mountain-shaped along the circumference of the sealing ring body and are continuously formed from the first and second conical surfaces of the convex portion formed at the tab, the dynamic pressure generation surface can be ensured more, thereby generating a large dynamic pressure.

[0030] Furthermore, preferably, the sealing ring includes: a non-sealing surface formed at a position closer to the bottom surface of the annular groove than the first sealing surface, and configured to form a gap between it and the side surface of the annular groove on the oil seal side; and a recess formed in the non-sealing surface along the circumference of the sealing ring body, the recess of the non-sealing surface having: a third conical surface continuously formed from the first conical surface formed at the protrusion, and inclinedly formed close to the width centerline; and a fourth conical surface continuously formed from the second conical surface formed at the protrusion, and inclinedly formed away from the width centerline from the bottom of the third conical surface.

[0031] In this way, by setting the recess of the non-sealing surface as a third and fourth conical surface that are valley-shaped along the circumference of the sealing ring body and are continuously formed from the first and second conical surfaces formed at the protrusion, the dynamic pressure generation surface can be ensured more, thereby generating a large dynamic pressure.

[0032] Furthermore, it is preferable that the first and second conical surfaces formed on the tabs are longer along the circumference of the sealing ring body compared to the third and fourth conical surfaces formed on the non-sealing surface.

[0033] Compared to the third and fourth conical surfaces formed on the non-sealing surface, the first and second conical surfaces formed on the tabs are made longer along the circumference of the sealing ring body, thereby ensuring a larger dynamic pressure generation surface and thus generating a large dynamic pressure.

[0034] Ideally, the top of the protrusion formed at the tab and the top of the protrusion formed on the non-sealing surface are linear, planar, or curved, and are closer to the width centerline side than the first sealing surface.

[0035] When the top of the protrusion is not located closer to the center line of the width than the first sealing surface (when it protrudes beyond the first sealing surface), the first sealing surface is difficult to slide into contact with the side of the annular groove of the shaft, resulting in a decrease in sealing performance.

[0036] Ideally, the top of the protrusion formed at the tab and the top of the protrusion on the non-sealing surface are continuously connected, and are inclined radially and axially toward the center of the sealing ring body and close to the width centerline.

[0037] In this way, the top of the protrusion formed at the tab and the top of the protrusion on the non-sealing surface are continuously connected, and are inclined radially toward the center of the sealing ring body and close to the width centerline, so that interference with the bottom of the annular groove can be avoided, and the tab can be further extended to the bottom side of the annular groove.

[0038] Furthermore, it is desirable that the bottom of the recess formed at the tab and the bottom of the recess on the non-sealing surface be any one of linear, planar, or curved.

[0039] Furthermore, it is desirable that the bottom of the recess formed at the tab and the bottom of the recess on the non-sealing surface are continuously connected.

[0040] Ideally, at least two of the tabs are formed on the inner circumferential surface of the sealing ring body.

[0041] The number of tabs may also be one; however, considering the centering function of avoiding a large deviation of the center of the sealing ring body from the center of the shaft and the generation of greater dynamic pressure, it is desirable to form at least two or more.

[0042] Typically, there are two or more protrusions on the inner circumferential surface of the sealing ring body, or there may be six or more, eight or more, or twelve or more. In addition, there are usually no more than 32, or no more than 28, no more than 24, or no more than 20.

[0043] Preferably, when the shaft with the sealing ring body mounted thereon is assembled inside the housing, the tab has a centering function that prevents the center of the sealing ring body from deviating significantly from the center of the shaft by abutting against the bottom surface of the annular groove.

[0044] According to the present invention, a sealing ring can be provided for sealing an annular gap between a housing and a shaft assembled therein, which can effectively generate dynamic pressure acting in the direction that moves the sealing surface of the sealing ring body away from the oil seal side of the annular groove, and can sufficiently reduce frictional torque even under high pressure and high speed rotation. Attached Figure Description

[0045] Figure 1 This is a top view of the sealing ring according to the first embodiment of the present invention.

[0046] Figure 2 yes Figure 1 A three-dimensional view of the sealing ring.

[0047] Figure 3 It will be formed in Figure 1 , Figure 2An enlarged top view of one of the multiple tabs (centering tabs) on the inner circumferential surface of the sealing ring.

[0048] Figure 4 yes Figure 3 A three-dimensional view of the protrusions.

[0049] Figure 5 yes Figure 3 Sectional view along line II.

[0050] Figure 6 It is Figure 1 The diagram shows a cross-sectional view of the sealing ring mounted on the shaft.

[0051] Figure 7 This is a top view showing an enlarged view of one of a plurality of tabs (centering tabs) formed on the inner circumferential surface of the sealing ring according to a second embodiment of the present invention.

[0052] Figure 8 yes Figure 7 A three-dimensional view of the protrusions.

[0053] Figure 9 yes Figure 7 Sectional view along line II-II.

[0054] Figure 10 This is a magnified top view showing one of a plurality of tabs (centering tabs) formed on the inner circumferential surface of the sealing ring according to the third embodiment of the present invention.

[0055] Figure 11 yes Figure 10 A three-dimensional view of the protrusions.

[0056] Figure 12 yes Figure 10 Sectional view along line III-III.

[0057] Figure 13 This is a top view showing an enlarged view of one of the plurality of tabs (centering tabs) formed on the inner circumferential surface of the sealing ring according to the fourth embodiment of the present invention.

[0058] Figure 14 yes Figure 13 A three-dimensional view of the protrusions.

[0059] Figure 15 yes Figure 13 Sectional view along line IV-IV.

[0060] Figure 16 This is a magnified top view showing one of a plurality of tabs (centering tabs) formed on the inner circumferential surface of the sealing ring according to the fifth embodiment of the present invention.

[0061] Figure 17yes Figure 16 A three-dimensional view of the protrusions.

[0062] Figure 18 yes Figure 16 VV-line sectional view.

[0063] Figure 19 It is a 3D diagram of a standard sealing ring.

[0064] Figure 20 It is a cross-sectional view of the shaft with a conventional sealing ring installed on the housing.

[0065] Figure 21 yes Figure 20 A magnified view of a portion of the image.

[0066] Figure 22 This is a perspective view showing another form of a conventional sealing ring. Detailed Implementation

[0067] (First Implementation)

[0068] Hereinafter, embodiments of the sealing ring according to the present invention will be described with reference to the accompanying drawings. The sealing ring according to this embodiment is, for example, assembled between a shaft and a housing that move relative to each other within the hydraulic circuit of an automatic transmission in an automobile, serving to seal the lubricating oil while sliding.

[0069] Figure 1 This is a top view of the sealing ring according to the first embodiment of the present invention. Figure 2 yes Figure 1 A three-dimensional view of the sealing ring. Furthermore, Figure 3 It will be formed in Figure 1 , Figure 2 An enlarged top view of one of the multiple protrusions on the inner circumferential surface of the sealing ring body. Figure 4 yes Figure 3 A three-dimensional view of the protrusions. Furthermore, Figure 5 yes Figure 3 Sectional view along line II, Figure 6 This is a cross-sectional view showing the sealing ring of the present invention installed in the annular groove of the shaft.

[0070] The sealing ring 1 shown in the figure is formed of resin materials such as PEEK and PPS, and includes: an annular sealing ring body 1A for sealing the gap between the housing and the shaft; and a plurality of protrusions 10 formed on the inner circumferential surface of the sealing ring body 1A. Moreover, the cross-section of the sealing ring body 1A is formed in a generally T-shape.

[0071] Specifically, such as Figure 6As shown, a first sealing surface 2 is provided on the oil seal side (sealing surface side) of the sealing ring body 1A. This first sealing surface 2 is in sliding contact with the side wall surface (the side surface of the oil seal side of the annular groove) 21a of the shaft 20, sealing the side wall surface 21a.

[0072] In addition, such as Figures 3 to 5 As shown, the sealing ring body 1A includes a non-sealing surface 3. This non-sealing surface 3 is positioned closer to the bottom surface 21b of the annular groove 21 (the center portion side of the sealing ring body 1A) than the first sealing surface 2, and is configured to form a gap 22 between itself and the sidewall surface 21a. The first sealing surface 2 and the non-sealing surface 3 are provided with a height difference via a step 4.

[0073] Furthermore, the outer peripheral surface of the sealing ring body 1A is the second sealing surface 5. This second sealing surface 5 contacts the inner peripheral surface 31 of the housing 30 and provides a seal.

[0074] In addition, such as Figure 6 As shown, non-sealing surfaces 6A and 6B are formed on the oil supply side (stepped surface) of the sealing ring body 1A. Furthermore, the sealing ring 1 is assembled onto the shaft 20 such that the non-sealing surface 6B and the inner circumferential surface 7 do not contact the annular groove 21.

[0075] In addition, such as Figure 1 , Figure 2 As shown, a plurality of protrusions 10 are provided at predetermined intervals on the inner circumferential surface 7 of the sealing ring body 1A.

[0076] One of the functions of the tab 10 is to prevent the center C of the sealing ring body 1A from deviating significantly from the center of the shaft 20 when the shaft 20 is assembled inside the housing 30.

[0077] That is, it has the function that, when the sealing ring 1 is assembled into the annular groove 21 of the shaft 20, if the sealing ring body 1A and the shaft 20 are offset from each other, the front end 10a of the protrusion 10 abuts against the bottom surface 21b of the annular groove 21, thereby preventing the center C of the sealing ring body 1A from deviating significantly from the center of the shaft 20 (see reference). Figure 6 ).

[0078] like Figure 3 and Figure 4 As shown, each tab 10 protrudes radially inward more than the inner circumferential surface 7. Moreover, when the sealing ring 1 is installed in the annular groove 21 of the shaft 20, if the sealing ring body 1A is offset from the shaft 20, the front end 10a of the tab 10 abuts against the bottom surface 21b of the annular groove 21.

[0079] Furthermore, a protrusion 10A is formed on the top of the tab 10 that protrudes radially inward from the inner circumferential surface 7.

[0080] Specifically, the protrusion 10A includes a so-called mountain-shaped conical surface formed circumferentially along the sealing ring body 1A, the conical surface being formed with: a first conical surface 10b, which protrudes from the tab 10 toward the first sealing surface 2; and a second conical surface 10c, which is formed obliquely from the upper end (top) of the first conical surface 10b along the tab direction.

[0081] That is, the protrusion 10A has: a first tapered surface 10b, which is inclined and formed away from the width center line Y (refer to...). Figure 6 ); and a second conical surface 10c, which is inclined to approach the width centerline Y from the top of the first conical surface 10b.

[0082] The conical surfaces 10b and 10c are used as hydrodynamic pressure generating surfaces. Depending on the flow direction of the lubricating oil, either conical surface 10b or conical surface 10c is used as the hydrodynamic pressure generating surface. For example... Figure 3 , Figure 4 As shown, when the lubricating oil flows in the direction of the arrow, the conical surface 10b is used as the hydrodynamic pressure generating surface.

[0083] In addition, such as Figure 3 , Figure 4 As shown, a protrusion 10B is formed on the non-sealing surface 3 where the tab 10 is located, extending circumferentially along the sealing ring body 1A.

[0084] Specifically, a mountain-shaped conical surface 10d and 10e are formed at the protrusion 10B. That is, the protrusion 10B has a third conical surface 10d, which is inclined and formed away from the width center line Y (refer to...). Figure 6 ); and a fourth conical surface 10e, which is inclined to approach the width centerline Y from the top of the third conical surface 10d.

[0085] The conical surfaces 10d and 10e are used as dynamic pressure generating surfaces. Similar to the conical surfaces 10b and 10c, depending on the flow direction of the lubricating oil, conical surface 10d is used as a dynamic pressure generating surface, or conical surface 10e is used as a dynamic pressure generating surface.

[0086] like Figure 3 and Figure 4 As shown, when the lubricating oil flows in the direction of the arrow, the conical surface 10d is used as the hydrodynamic pressure generating surface.

[0087] The conical surfaces 10b and 10d are formed continuously (forming the same plane), and the conical surfaces 10c and 10e are formed continuously (forming the same plane). That is, the protrusions 10A and 10B are formed continuously.

[0088] In this way, since the conical surfaces 10d and 10e are formed continuously from the conical surfaces 10b and 10c respectively, a conical surface with a larger radial area can be formed compared with the case where the conical surface is formed only on the non-sealing surface 3, and a larger dynamic pressure can be effectively generated.

[0089] The conical surfaces 10b and 10d only need to be formed continuously, and their cone angles (inclination angles) can be different. Similarly, the conical surfaces 10c and 10e only need to be formed continuously, and their cone angles can be different.

[0090] In particular, it is preferred that conical surfaces 10b and 10d are formed continuously and are identical surfaces with the same cone angle. Similarly, it is preferred that conical surfaces 10c and 10e are formed continuously and are identical surfaces with the same cone angle.

[0091] like Figure 3 , Figure 4 As shown, the tops (vertices) 10A1 and 10B1 of the protrusions 10A and 10B are formed in a linear shape. Furthermore, as... Figure 5 , Figure 6 As shown, the tops 10A1 and 10B1 are inclined such that they approach the width centerline Y in a radial and axial direction toward the sealing ring body 1A.

[0092] Because of this configuration, interference with the bottom surface 21b of the annular groove 21 can be avoided, and the protrusion 10 can be further extended to the bottom surface 21b side of the annular groove 21.

[0093] like Figure 6 As shown, the tops 10A1 and 10B1 are closer to the width centerline Y side than the first sealing surface 2. When the tops (apexes) 10A1 and 10B1 of the protrusion are not located closer to the width centerline Y side than the first sealing surface 2 (when they protrude beyond the first sealing surface), the first sealing surface 2 is difficult to slide into contact with the side surface 21a of the annular groove 21 of the shaft, resulting in reduced sealing performance.

[0094] Furthermore, although the tops 10A1 and 10B1 of the protrusions 10A and 10B are shown as being formed in a linear shape, the tops can also be either planar or curved. For example, they can be trapezoidal protrusions or arc-shaped protrusions.

[0095] In addition, such as Figure 1 and Figure 2 As shown, a joint 1a is formed at one point in the circumference of the sealing ring 1. When mounted on the shaft 20, the sealing ring 1 can be easily installed in the annular groove 21 of the shaft 20 by expanding its diameter in the direction separating the joint 1a.

[0096] The sealing ring 1 constructed in this way is as follows: Figure 6 When the sealing ring 1 is installed at the annular groove 21 of the shaft 20, if the pressure P of the lubricating oil acts from the oil supply side (annular gap 40 side) in the direction of arrow P, the sealing ring 1 is pressed to the oil seal side (annular gap 41 side).

[0097] Furthermore, the first sealing surface 2 on the oil seal side of the sealing ring 1 slides in contact with the side wall surface 21a of the annular groove 21, and the second sealing surface 5 contacts the inner circumferential surface 31 of the housing 30. This prevents lubricating oil from leaking to the oil seal side.

[0098] Furthermore, even if the shaft 20 rotates, the sealing ring 1 itself does not rotate much, and the second sealing surface 5 of the sealing ring 1 and the inner circumferential surface 31 of the housing 30 are in contact with each other to suppress sliding.

[0099] On the other hand, the first sealing surface 2 on the oil seal side slides against the side wall surface 21a of the annular groove 21 of the shaft 20. An oil film is formed between the first sealing surface 2 and the side wall surface 21a by a certain degree of lubricating oil leakage, and the first sealing surface 2 and the side wall surface 21a slide through the oil film.

[0100] Furthermore, with the sealing ring 1 pressurized by lubricating oil from the oil supply side, when the shaft 20 rotates, the lubricating oil between the non-sealing surface 3 and the side wall surface 21a of the annular groove 21 is affected by the relative motion generated by the rotation of the shaft 20, and moves along the non-sealing surface 3 and the side wall surface 21a. Figure 3 , Figure 4 The flow is in the direction of the arrow (axis rotation direction).

[0101] Here, as Figure 3 , Figure 4 As shown, in the sealing ring 1 of the present invention, not only are a third conical surface 10d and a fourth conical surface 10e formed at the non-sealing surface 3, but also a first conical surface 10b and a second conical surface 10c (which are mountain-shaped along the circumference of the sealing ring body 1A) extending radially inward are formed at a plurality of protrusions 10 formed on the inner circumferential surface of the sealing ring 1.

[0102] Furthermore, by utilizing the tapered surface 10d of the non-sealing surface 3 and the tapered surface 10b of the protrusion 10, a flow of lubricating oil is formed that generates dynamic pressure between the non-sealing surface 3 and the sidewall surface 21a of the annular groove 21. Through this dynamic pressure effect, a force is applied that moves the first sealing surface 2 of the sealing ring 1 away from the sidewall surface 21a of the annular groove 21. This effectively reduces the sliding friction force generated between the first sealing surface 2 and the sidewall surface 21a. In addition, the force that moves the first sealing surface 2 of the sealing ring 1 away from the sidewall surface 21a of the annular groove 21 allows an appropriate oil film to exist at the sliding surface, thereby reducing frictional torque.

[0103] That is, between the non-sealing surface 3 and the side wall surface 21a of the annular groove 21, a narrowest wedge-shaped flow path is formed at the top of the mountain-shaped conical surface, and a wedge-shaped flow path is also formed at the top of the conical surface extending radially inward toward the tab 10. Moreover, lubricating oil flows in this wedge-shaped flow path, thereby generating dynamic pressure.

[0104] These conical surfaces are dynamic pressure generating surfaces. Compared to forming conical surfaces only on the non-sealing surface 3, forming conical surfaces on the tabs 10 also allows for a larger dynamic pressure generating surface, thus achieving a more effective dynamic pressure effect.

[0105] As a result, the sealing ring 1 can be subjected to force in the direction away from the side wall surface 21a of the annular groove 21, which reduces the sliding friction force generated at the sliding surface. In addition, an appropriate oil film can be present at the sliding surface, which can reduce the friction torque.

[0106] As described above, according to the first embodiment of the present invention, a tab 10 is used to prevent the center of the sealing ring 1 from deviating significantly from the axis of the shaft 20. A mountain-shaped conical surface is formed on the tab 10 along the circumference of the sealing ring body 1A. Therefore, dynamic pressure can be generated more effectively than if the conical surface is formed only on the non-sealing surface 3.

[0107] As a result, the sliding friction force generated at the sliding surface can be reduced, an appropriate oil film can be present at the sliding surface, and the friction torque can be effectively reduced.

[0108] Furthermore, in the above embodiment, it was explained that a larger dynamic pressure generating surface can be formed by forming a tapered surface at the protrusion 10. However, it is not necessary to form a tapered surface on the entire surface of the first sealing surface side of the protrusion 10. It is sufficient that an inclined portion that is inclined when viewed radially from the sealing ring body is formed at at least a portion of the first sealing surface side of the protrusion.

[0109] Furthermore, in the above embodiments, in Figure 1 The illustration shows a case where 16 tabs 10 are provided at the sealing ring 1; however, in this invention, the number of tabs 10 is not particularly limited to 16. Although a greater number of tabs 10 can generate dynamic pressure more effectively, an excessive number of tabs 10 will reduce the dynamic pressure generated on each tab, and is therefore not preferred. The number of tabs is typically 2 or more, but can also be 6 or more, 8 or more, or 12 or more; in addition, it is typically 32 or less, but can also be 28 or less, 24 or less, or 20 or less.

[0110] (Second Implementation)

[0111] In the first embodiment, it is described that a protrusion 10A is formed at the tab 10 and a protrusion 10B is formed on the non-sealing surface 3 where the tab 10 is located. However, the present invention is not limited to the protrusion and may also be a recess.

[0112] according to Figures 7 to 9 The case of this recess will be described as a second embodiment. Furthermore, in the second embodiment, the same reference numerals are used to denote common parts with the first embodiment, and their detailed descriptions are omitted.

[0113] Specifically, such as Figures 7 to 9 As shown, recesses 11A and 11B can be used as dynamic pressure generating surfaces. Recesses 11A and 11B pass through the axial center of the second sealing surface 5 of the sealing ring body 1A, along a line approximately equal to the axial centerline X (refer to...) of the sealing ring body 1A. Figure 6 The orthogonal width centerline Y is concave in the direction of the curve.

[0114] The recess 11A is provided at the protrusion 10. The recess 11A has: a first conical surface 11b, which is formed by a plane or a curved surface and is inclined to approach the width center line Y; and a second conical surface 11c, which is formed by a plane or a curved surface and is inclined to move away from the width center line Y from the bottom of the first conical surface 11b.

[0115] That is, the recess 11A includes a valley-shaped conical surface circumferentially toward the sealing ring body 1A. Moreover, by forming a wedge-shaped flow path along the circumference of the sealing ring 1 through the first conical surface 11b and the second conical surface 11c (the valley-shaped conical surface circumferentially along the sealing ring body), the conical surface can be used as a dynamic pressure generating surface.

[0116] Furthermore, a recess 11B is provided at the non-sealing surface 3, which is formed circumferentially along the sealing ring body 1A.

[0117] The recess 11B of the non-sealing surface has a third conical surface 11d and a fourth conical surface 11e. The third conical surface 11d is continuously formed from the first conical surface 11b formed at the protrusion and is inclined to approach the width center line. The fourth conical surface 11e is continuously formed from the second conical surface 11c formed at the protrusion 10 and is inclined to move away from the width center line from the bottom of the third conical surface 11d.

[0118] In addition, the recess 11B can be provided not only at the position corresponding to the recess 11A of the protrusion 10, but also on the entire circumference of the sealing ring body 1A.

[0119] Furthermore, it was described that the bottom 11A1 of the recess 11A formed at the protrusion 10 and the bottom 11B1 of the recess 11B on the non-sealing surface 3 are formed in a linear shape. However, like the top in the first embodiment, it can also be either a plane or a curved surface. For example, it can be a trapezoidal recess or an arc-shaped recess.

[0120] In addition, similar to the top of the first embodiment, the bottom 11A1 of the recess 11A formed at the protrusion 10 and the bottom 11B1 of the recess 11B of the non-sealing surface 3 are continuously connected.

[0121] In this way, by setting the recess 11B of the non-sealing surface as a conical surface 11d and 11e formed continuously from the first and second conical surfaces 11b and 11c, the dynamic pressure generating surface can be ensured more, thereby generating a large dynamic pressure.

[0122] Additionally, along the lubricating oil Figure 7 , Figure 8 When the flow is in the direction of the arrow, conical surfaces 11c and 11e become dynamic pressure generating surfaces. Furthermore, when the lubricating oil flows along the direction of the arrow... Figure 7 , Figure 8 When the flow is in the opposite direction to the arrow, the conical surfaces 11b and 11d become the dynamic pressure generating surfaces.

[0123] (Third Implementation)

[0124] Next, use Figures 10 to 12 The third embodiment of the present invention will be described. Furthermore, in this third embodiment, since only the shape of the tab 10 differs from that of the first embodiment, the common parts are indicated by the same reference numerals, and their detailed descriptions are omitted.

[0125] Each protrusion 10 is the same as in the first embodiment, such as... Figure 10 , Figure 11 The inner circumferential surface 7 protrudes further radially inward, and its front end 10a abuts against the bottom surface 21b of the annular groove 21.

[0126] Furthermore, a protrusion 10A is formed on the top of the tab 10. The protrusion 10A has mountain-shaped conical surfaces 10b and 10c along the circumference of the sealing ring body 1A.

[0127] In addition, such as Figure 11 , Figure 12 As shown, a protrusion 10B is formed on the non-sealing surface 3. The protrusion 10B has a mountain-shaped conical surface 10d and 10e relative to the non-sealing surface 3 along the circumferential direction of the sealing ring body 1A.

[0128] The conical surfaces 10d and 10e are formed continuously from the conical surfaces 10b and 10c, respectively.

[0129] Furthermore, conical surfaces 10f and 10g are provided continuously extending outward from the conical surfaces 10b and 10c. These conical surfaces 10f and 10g extend further outward than the conical surfaces 10d and 10e formed on the non-sealing surface 3.

[0130] Therefore, compared to forming a conical surface (protrusion) only on the non-sealing surface 3, a larger conical surface can be formed along the radial and circumferential directions of the sealing ring body 1A. That is, by forming a larger conical surface (dynamic pressure generating surface), a larger dynamic pressure can be effectively generated.

[0131] The tilt angle θ1 of the conical surfaces 10f and 10g, which extend circumferentially more than the conical surfaces 10d and 10e formed on the non-sealed surface 3, is set to be larger than the tilt angle θ2 of the conical surfaces 10d and 10e.

[0132] (Fourth Implementation)

[0133] Next, use Figures 13 to 15 The fourth embodiment of the present invention will be described. In this fourth embodiment, the sealing ring 1 is formed in the same annular shape as in the first to third embodiments; however, its cross-section is formed in a generally rectangular shape (i.e., the non-sealing surface 3 of the first to third embodiments is not formed).

[0134] As shown in the figure, a plurality of protrusions 10 are provided on the inner circumferential surface of the sealing ring 1. Each protrusion 10 protrudes further radially inward than the inner circumferential surface 7, and, as in other embodiments, its front end 10a abuts against the bottom surface 21b of the annular groove 21.

[0135] In addition, such as Figure 15 As shown, a protrusion 10C is formed on the top of the tab 10 that protrudes radially inward from the inner circumferential surface 7. At this protrusion 10C, mountain-shaped conical surfaces 10b and 10c are formed along the circumference of the sealing ring body 1A.

[0136] Furthermore, conical surfaces 10f and 10g are continuously formed outward from the conical surfaces 10b and 10c, respectively.

[0137] Therefore, even without forming a non-sealed surface 3, the surface for generating dynamic pressure can be ensured to a greater extent, thereby effectively generating dynamic pressure.

[0138] (Fifth Implementation)

[0139] Next, use Figure 16 and Figure 18The fifth embodiment of the present invention will be described. In the third embodiment, the following situation was described: the protrusion 10A has a mountain-shaped conical surface 10b, 10c along the circumference of the sealing ring body 1A, and the protrusion 10B has a mountain-shaped conical surface 10d, 10e relative to the non-sealing surface 3 along the circumference of the sealing ring body 1A.

[0140] In this embodiment, conical surfaces 10b and 10d are formed at the protrusions 10A and 10B along the circumference of the sealing ring body 1A, but conical surfaces 10c and 10e are not formed. That is, the surfaces corresponding to conical surfaces 10c and 10e are formed as vertical surfaces 10h and 10i.

[0141] Specifically, each protrusion 10 is the same as in the third embodiment, such as... Figures 16 to 18 As shown, it protrudes radially inward more than the inner circumferential surface 7, and, as in other embodiments, its front end 10a abuts against the bottom surface 21b of the annular groove 21.

[0142] Furthermore, a protrusion 10A is formed on the top of the tab 10. This protrusion 10A has a tapered surface 10b along the circumference of the sealing ring body 1A. Moreover, as described above, the surface continuous with the tapered surface 10b is formed as a vertical surface 10h.

[0143] In addition, such as Figure 16 , Figure 17 As shown, a protrusion 10B is formed on the non-sealing surface 3. This protrusion 10B has a mountain-shaped conical surface 10d relative to the non-sealing surface 3 along the circumferential direction of the sealing ring body 1A. Moreover, as described above, the surface continuous with the conical surface 10d is formed as a vertical surface 10i.

[0144] Furthermore, the conical surface 10d is continuously formed from the conical surface 10b.

[0145] Furthermore, conical surfaces 10f1 and 10f2 are provided continuously extending outward from the conical surface 10b. These conical surfaces 10f1 and 10f2 extend further outward than the conical surface 10d formed on the non-sealing surface 3.

[0146] Therefore, compared to forming a conical surface (protrusion) only on the non-sealing surface 3, a larger conical surface can be formed along the radial and circumferential directions of the sealing ring body 1A. That is, by forming a larger conical surface (dynamic pressure generating surface), a larger dynamic pressure can be effectively generated.

[0147] Furthermore, since the conical surfaces 10b and 10d are formed along one direction of the circumference of the sealing ring body 1A, when these conical surfaces 10b and 10d are used as hydrodynamic pressure generating surfaces, the direction of lubricating oil flow is specified as follows: Figure 16 , Figure 17 The arrow indicates a direction.

[0148] Furthermore, in the description of the first to fourth embodiments described above, the case in which the tab 10 is formed on the oil seal side (sealing surface side) of the sealing ring body 1A was explained.

[0149] However, in this invention, the protrusion 10 can be formed not only on the oil seal side (sealing surface side) of the sealing ring body 1A, but also on the non-sealing surface 6B side. That is, protrusions 10 with inclined portions can be provided on both sides of the sealing ring body 1A.

[0150] In this way, when a sealing ring has protrusions formed on both the sealing surface side and the non-sealing surface side, either side of the sealing ring can be used as the oil seal side (sealing surface). That is, there is no directional requirement for the installation of the sealing ring, and it can be easily assembled onto the shaft.

[0151] Furthermore, in the sealing ring with protrusions formed on both the sealing surface and non-sealing surface sides, as described in the first to fourth embodiments above, the protrusions on the sealing surface side generate dynamic pressure through the inclined portion. However, since the distance between the protrusions on the non-sealing surface side and the annular groove side surface of the shaft (the groove side surface on the oil supply side) increases, the dynamic pressure generated by the inclined portion is very small.

Claims

1. A sealing ring, said sealing ring being an annular ring used to seal the gap between a housing and a shaft, characterized in that, At least including: The main body of the sealing ring is circular. A first sealing surface is formed at the sealing ring body and slides in contact with the side of the annular groove of the shaft. A second sealing surface is formed at the sealing ring body and contacts the inner circumferential surface of the housing; and Multiple tabs are formed on the inner circumferential surface of the sealing ring body in a radially inward manner to prevent the center of the sealing ring from deviating significantly from the center of the shaft when the shaft is assembled onto the housing. An inclined portion, which is inclined when viewed radially from the sealing ring body, is formed at least a portion of the first sealing surface side of the protrusion. The surface forming the inclined portion passes through the axial center of the second sealing surface, and is located only closer to the first sealing surface than the width centerline orthogonal to the axial centerline of the sealing ring body. The inclined portion formed at least a portion of the first sealing surface side of the tab forms a protrusion, which protrudes along a direction away from the width centerline of the sealing ring body. Wherein, the protrusion formed at the tab includes a conical surface that is mountain-shaped when viewed radially from the sealing ring body, the conical surface having: The first conical surface is composed of a plane or a curved surface, and is inclined away from the center line of the width; and The second conical surface is composed of a plane or a curved surface, and is inclined such that it approaches the center line of the width from the top of the first conical surface. The sealing ring also includes: A non-sealing surface, formed at a position closer to the bottom surface of the annular groove than the first sealing surface, and configured to form a gap between itself and the side surface of the annular groove on the oil-seal side; and The protrusion is formed circumferentially along the non-sealing surface of the sealing ring body. The protrusion of the non-sealing surface has: The third conical surface is continuously formed from the first conical surface formed at the protrusion, and is obliquely formed away from the width centerline; and The fourth conical surface is formed continuously from the second conical surface formed at the protrusion, and is inclined to approach the width centerline from the top of the third conical surface.

2. The sealing ring according to claim 1, characterized in that, Compared to the third and fourth conical surfaces formed on the non-sealing surface, the first and second conical surfaces formed on the tab are longer along the circumference of the sealing ring body.

3. The sealing ring according to claim 1, characterized in that, The top of the protrusion formed at the tab is any one of linear, planar, or curved, and is closer to the width centerline side than the first sealing surface.

4. The sealing ring according to claim 1, characterized in that, The top of the protrusion on the non-sealing surface is any one of linear, planar, or curved, and is closer to the width centerline side than the first sealing surface.

5. The sealing ring according to claim 3, characterized in that, The tops of the protrusions formed at the tabs are continuously connected and are inclined to approach the width centerline radially and axially toward the sealing ring body.

6. The sealing ring according to claim 4, characterized in that, The tops of the protrusions on the non-sealing surface are continuously connected and are inclined to approach the width centerline radially and axially toward the sealing ring body.

7. The sealing ring according to claim 1, characterized in that, Two or more of the aforementioned protrusions are formed on the radial inner surface, i.e., the inner circumferential surface, of the sealing ring body.

8. The sealing ring according to claim 1, characterized in that, When the shaft with the sealing ring body installed is assembled inside the housing, the tab has a centering function that prevents the center of the sealing ring body from deviating significantly from the center of the shaft by abutting against the bottom surface of the annular groove.

9. A sealing ring, said sealing ring being an annular ring for sealing the gap between a housing and a shaft, characterized in that, At least including: The main body of the sealing ring is circular. A first sealing surface is formed at the sealing ring body and slides in contact with the side of the annular groove of the shaft. A second sealing surface is formed at the sealing ring body and contacts the inner circumferential surface of the housing; and Multiple tabs are formed on the inner circumferential surface of the sealing ring body in a radially inward manner to prevent the center of the sealing ring from deviating significantly from the center of the shaft when the shaft is assembled onto the housing. An inclined portion, which is inclined when viewed radially from the sealing ring body, is formed at least a portion of the first sealing surface side of the protrusion. The surface forming the inclined portion passes through the axial center of the second sealing surface, and is located only closer to the first sealing surface than the width centerline orthogonal to the axial centerline of the sealing ring body. Wherein, the inclined portion formed at least a portion on the first sealing surface side of the protrusion forms a recess, the recess being recessed along a direction close to the width centerline of the sealing ring body. Wherein, the recess formed at the protrusion includes a conical surface that is valley-shaped when viewed radially from the sealing ring body, the conical surface having: The first conical surface is composed of a plane or a curved surface, and is inclined to approximate the center line of the width; and The second conical surface is composed of a plane or a curved surface, and is inclined such that it extends away from the center line of the width from the bottom of the first conical surface. The sealing ring also includes: A non-sealing surface, formed at a position closer to the bottom surface of the annular groove than the first sealing surface, and configured to form a gap between itself and the side surface of the annular groove on the oil-seal side; and A recess is formed in the non-sealing surface along the circumference of the sealing ring body. The recess of the non-sealing surface has: The third conical surface is continuously formed from the first conical surface formed at the protrusion, and is inclined to approach the center line of the width; and The fourth conical surface is formed continuously from the second conical surface formed at the protrusion, and is inclined to extend away from the width centerline from the bottom of the third conical surface.

10. The sealing ring according to claim 9, characterized in that, The bottom of the recess formed at the protrusion is any one of linear, planar, or curved.

11. The sealing ring according to claim 9, characterized in that, The bottom of the recess on the non-sealed surface can be any one of a linear, planar, or curved surface.

12. The sealing ring according to claim 10, characterized in that, The recesses formed at the protrusions are continuously connected at their bottoms.

13. The sealing ring according to claim 11, characterized in that, The bottom of the recess on the non-sealed surface is continuously connected.

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