Sealing ring

Abstract

Provided is a seal ring capable of maintaining the degree of parallelism between sliding surfaces. A seal ring is provided with: a sliding surface (3a) that slides relative to a shaft (1) or a housing (2) into which the shaft (1) is inserted; and a seal ring (3b) that intersects the sliding surface (3a) and is provided on the other one of the shaft (1) and the housing (2), the seal ring (3b) dividing between one space (H) on the opposite side of the sliding surface (3a) from the side intersecting the installation surface (3b) and the other space (L) disposed on the side intersecting the installation surface (3b), the sliding surface (3a) being provided with: a dynamic pressure generation mechanism (36) that generates dynamic pressure from the other space (L); a dynamic pressure generator (39b) which communicates with the one space (H) and which has a dynamic pressure generating section (39b); and a fluid recovery mechanism (37) disposed between the dynamic pressure generation unit (39b) and the one space (H).

Description

Technical Field

[0001] This invention relates to a sealing ring used for sealing the gap between a shaft and a housing, and particularly to a sealing ring used for installation in an annular groove, also known as a stuffing box. Background Technology

[0002] As a shaft sealing device to prevent leakage of the sealed fluid, there exists, for example, an annular sealing ring disposed between the rotating shaft and the housing of rotating machinery. In recent years, for environmental countermeasures and other reasons, it has been desirable to reduce the energy lost due to slippage in such sealing rings.

[0003] For example, as shown in Patent Document 1, the sealing ring is fixed to the housing and is rotatably fitted into an annular groove provided on the rotating shaft, and the side of the sealing ring and the side of the annular groove can slide relative to each other.

[0004] Furthermore, an oil groove communicating with the oil chamber side and a wedge-effect generating groove extending circumferentially from the oil groove are provided on the side of the sealing ring. When the rotating shaft rotates, working oil is drawn from the oil chamber through the oil groove, and dynamic pressure is generated through the wedge effect of the wedge-effect generating groove, causing the side of the sealing ring to float from the side of the annular groove to form an oil film. This reduces the friction between the side of the sealing ring and the side of the annular groove.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 9-210211 (page 4) Figure 4 ) Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] In the sealing ring of Patent Document 1, the sealing ring is configured to extend outward from the annular groove of the rotating shaft, and no dynamic pressure based on the wedge effect is generated on the outer diameter side of the sealing ring. Therefore, dynamic pressure is generated only on the inner diameter side of the sealing ring, thus causing the sealing ring to twist with the inner diameter side away from the side of the annular groove and the outer diameter side close to the side of the annular groove, potentially reducing the effect of generating dynamic pressure.

[0010] Methods for solving problems

[0011] This invention was made in view of such a problem, and its purpose is to provide a sealing ring that can maintain the parallelism between the sliding surfaces.

[0012] To address the aforementioned issues, the sealing ring of the present invention comprises: a sliding surface that rotates and slides relative to a shaft or a housing through which the shaft is inserted; and a setting surface that intersects the sliding surface and is disposed on the other side of the shaft and the housing. The sealing ring divides a space on the opposite side of the side of the sliding surface that intersects with the setting surface and another space disposed on the side that intersects with the setting surface. The sliding surface is provided with: a dynamic pressure generating mechanism communicating with the first space and having a dynamic pressure generating portion; and a fluid recovery mechanism disposed between the dynamic pressure generating portion and the first space.

[0013] Therefore, the pressure on one side of the positive pressure generated near the dynamic pressure generating section of the dynamic pressure generating mechanism is released by the fluid recovery mechanism through the pressure difference with the other side of the sliding surface, thus suppressing the pressure on the other side of the sliding surface. Furthermore, since the fluid recovery mechanism is surrounded by the land area, it is less likely to interfere with the dynamic pressure generating mechanism during relative rotation, and less likely to be affected by the other side of the sliding surface when stationary. Therefore, torsion that would cause one side of the sliding surface to move away from the other side and the other side to move closer to the other side is less likely to occur, maintaining the parallelism of the sliding surfaces.

[0014] Alternatively, the fluid recovery mechanism may be positioned on the side closer to the space in question.

[0015] Therefore, it is easy to discharge the fluid in the fluid recovery mechanism into a space.

[0016] Alternatively, the width of the land portion between the fluid recovery mechanism and the space may be smaller than the width of the fluid recovery mechanism.

[0017] Therefore, it is easy to discharge the fluid in the fluid recovery mechanism into a space.

[0018] Alternatively, the fluid recovery mechanism may be formed to be relatively long in the circumferential direction.

[0019] Thus, a flow of fluid toward the downstream side of the relative circumferential rotation is generated within the fluid recovery mechanism, making it easy to recover the fluid between the sliding surfaces through the flow of fluid within the fluid recovery mechanism.

[0020] Alternatively, the fluid recovery mechanism may be configured such that the downstream end is rotated relative to the space side.

[0021] Therefore, it is easy to discharge the fluid in the fluid recovery mechanism into a space.

[0022] Alternatively, the depth of the fluid recovery mechanism may become shallower from the downstream side of the relative rotation toward the upstream side of the relative rotation.

[0023] This allows for the generation of a relative negative pressure on the upstream side of the fluid recovery mechanism, making it easier to draw in fluid between the sliding surfaces.

[0024] Alternatively, the fluid recovery mechanism can be a deep tank.

[0025] This allows for the intake of a large amount of fluid between the sliding surfaces, thus making it easier to reduce the pressure on one side of the sliding surface.

[0026] Alternatively, the dynamic pressure generating mechanism may consist of a fluid inlet channel and a dynamic pressure generating channel, wherein the fluid inlet channel is in communication with one of the spaces, and the dynamic pressure generating channel extends circumferentially from the fluid inlet channel and is shallower than the fluid inlet channel.

[0027] Therefore, the sealed fluid can be efficiently introduced from the fluid inlet channel, which is a deep groove, into the dynamic pressure generating channel, resulting in high dynamic pressure generation effect of the dynamic pressure generating unit.

[0028] Alternatively, the dynamic pressure generating groove may become shallower from the upstream side of the relative rotation toward the downstream side of the relative rotation.

[0029] Therefore, the dynamic pressure generating unit has a high dynamic pressure generation effect. Attached Figure Description

[0030] Figure 1 This is a schematic cross-sectional view showing a shaft sealing device with a sealing ring applied according to Embodiment 1 of the present invention.

[0031] Figure 2 (a) is a diagram showing the sealing ring viewed from the axial direction. Figure 2 (b) is an enlarged view of the cut section viewed from the axial direction. Figure 2 (c) is the view observed along arrow A.

[0032] Figure 3 (a) is an enlarged view of the dynamic pressure generating tank and fluid recovery tank of Example 1, viewed from the axial direction. Figure 3 (b) is a sectional view along line AA.

[0033] Figure 4 This is a schematic cross-sectional view showing the state in which dynamic pressure is generated by the dynamic pressure generating groove.

[0034] Figure 5 This is an enlarged view of the dynamic pressure generating tank and fluid recovery tank of Embodiment 2 of the present invention, viewed from the axial direction.

[0035] Figure 6 This is an enlarged view of the dynamic pressure generating tank and fluid recovery tank of Embodiment 3 of the present invention, viewed from the axial direction.

[0036] Figure 7 This is an enlarged view of the dynamic pressure generating tank and fluid recovery tank of Embodiment 4 of the present invention, viewed from the axial direction.

[0037] Figure 8 This is an enlarged view of the dynamic pressure generating tank and fluid recovery tank of Embodiment 5 of the present invention, viewed from the axial direction.

[0038] Figure 9 This is an enlarged view of the dynamic pressure generating tank and fluid recovery tank of Embodiment 6 of the present invention, viewed from the axial direction.

[0039] Figure 10 This is a schematic cross-sectional view showing a shaft sealing device with a sealing ring applied according to Embodiment 7 of the present invention.

[0040] Figure 11 This is a schematic cross-sectional view showing a shaft sealing device with a sealing ring applied according to Embodiment 8 of the present invention.

[0041] Figure 12 This is an enlarged view of a modified example of the fluid recovery tank of Embodiment 1 of the present invention, viewed from the axial direction. Detailed Implementation

[0042] Hereinafter, the manner in which the sealing ring is used to implement the present invention will be described based on embodiments.

[0043] Example 1

[0044] Reference Figures 1 to 4 The sealing ring of Example 1 will be described. Furthermore, in this example, the sealing ring will... Figure 1 The right side of the paper serves as the right side of the sealing ring. Figure 1 The left side of the paper is used as the left side of the sealing ring for explanation. In addition, for ease of explanation, the dynamic pressure generating tank 36, fluid recovery tank 37, etc. are shown as larger than their actual size.

[0045] Figure 1 The shaft sealing device shown is suitable for applications such as sealing the annular gap between a rotating shaft 1 and a housing 2 in rotating equipment to maintain hydraulic pressure. In this embodiment, an example of such an application will be described. Furthermore, in... Figure 1 The image shows a state where no dynamic pressure is generated in the dynamic pressure generating groove 36 of the sealing ring 3.

[0046] The shaft sealing device mainly consists of a rotating shaft 1 (which serves as the shaft), a housing 2, and a sealing ring 3. The sealing ring 3 is fitted into an annular groove 1A with a rectangular cross-section, which is provided on the rotating shaft 1.

[0047] As described later, the right surface 3a of the sealing ring 3, which serves as the sliding surface, slides against the right surface 1a of the annular groove 1A, which serves as the opposing sliding surface. The outer peripheral surface 3b of the sealing ring 3, which serves as the setting surface, is pressed against the inner peripheral surface 2a of the housing 2, which serves as the setting surface. That is, the setting surface and the setting surface only need to be in contact with each other, for example, in a situation where the lubrication of the sliding surface is insufficient, such as when the equipment is started, allowing the setting surface and the setting surface to slide.

[0048] Furthermore, the right surface 3a of the sealing ring 3 has a portion that abuts against the right surface 1a of the annular groove 1A and a portion disposed on the outer diameter side of the right surface 1a of the annular groove 1A. In this embodiment, the sliding surface of the sealing ring 3 refers to the entire surface of the right surface 3a of the sealing ring 3. That is, the sliding surface of the sealing ring 3 includes the portion that abuts against the right surface 1a of the annular groove 1A and the portion that is coplanar with that portion.

[0049] Furthermore, the angles between the outer peripheral surface 3b and the right surface 3a, and between the outer peripheral surface 3b and the left surface of the sealing ring 3, are stepped portions with cuts. This facilitates maintaining the press-fit state between the outer peripheral surface 3b and the inner peripheral surface 2a. This is because the sealing ring 3 can undergo slight deformation itself when subjected to external forces such as fluid pressure.

[0050] In this embodiment, the configuration is as follows: Figure 1 The sealing ring 3 maintains the fluid pressure in the sealing target area (H) on the left side of the figure, which is affected by fluid pressure changes. The sealing target area (H), which is one space, is positioned on the opposite side of the outer peripheral surface 3b with reference to the right surface 3a of the sealing ring 3, and the leakage area (L), which is the other space, is positioned on the side of the outer peripheral surface 3b with reference to the right surface 3a of the sealing ring 3.

[0051] Furthermore, although not illustrated, when the equipment using sealing ring 3 is stopped, the fluid pressure in the sealed area (H) is low, compared to... Figure 1 The leakage area (L) on the right side is under the same pressure. When the equipment is in operation, the fluid pressure in the sealing area (H) becomes higher than that in the leakage area (L).

[0052] The sealing ring 3 is made of resin materials such as polyetheretherketone (PEEK), polyphenylene sulfide (PPS), and polytetrafluoroethylene (PTFE).

[0053] like Figure 2 As shown in (a) to (c), the sealing ring 3 has a cut-off portion 31 formed at point 1 in the circumferential direction. Furthermore, Figure 2 (b) is Figure 2 Enlarged view of the enclosing part of (a).

[0054] The cutting section 31 is from both sides of the axial direction (see reference). Figure 2 (a), (b)) and the outer diameter side (refer to) Figure 2 (c) The known special stepped cut that appears as a stepped cut when observed. Thus, in the sealing ring 3, a first fitting protrusion 32 and a first fitting recess 33 are provided on the outer peripheral surface side on one circumferential side, and a second fitting recess 34 for the first fitting protrusion 32 to be inserted and a second fitting protrusion 35 inserted into the first fitting recess 33 are provided on the outer peripheral surface side on the other circumferential side.

[0055] Furthermore, the cutting portion 31 includes not only cases where it is cut by machining, but also cases where it is formed by molding. Also, here, as an example of the cutting portion 31, a special stepped cut is shown, but it is not limited to this; known straight cuts, bias cuts, stepped cuts, etc., can also be used. Additionally, if a low-elasticity material (such as PTFE) is used as the material of the sealing ring 3, the cutting portion may not be provided.

[0056] And, as Figure 2 (b) and Figure 3 As shown, multiple dynamic pressure generating grooves 36 (serving as dynamic pressure generating mechanisms) and multiple fluid recovery grooves 37 (serving as fluid recovery mechanisms) are formed circumferentially on the right surface 3a of the sealing ring 3. In this embodiment, multiple sets of a dynamic pressure generating groove 36 and a fluid recovery groove 37 disposed downstream of the rotation axis 1 of the dynamic pressure generating groove 36 are arranged circumferentially on the right surface 3a of the sealing ring 3.

[0057] Furthermore, the number of dynamic pressure generating grooves 36 and fluid recovery grooves 37 can be freely varied. For example, the number of dynamic pressure generating grooves 36 and fluid recovery grooves 37 provided on the right surface 3a of the sealing ring 3 can also be different.

[0058] Especially as Figure 3 As shown in (a) and (b), the dynamic pressure generating tank 36 has a first tank portion 38 as a fluid inlet tank and a second tank portion 39 as a dynamic pressure generating tank.

[0059] The first groove 38 extends radially in a straight line from the inner diameter end 38a toward the outer diameter end 38b. The inner diameter end 38a communicates with the sealing target area (H). The outer diameter side of the outer diameter end 38b is closed by the land portion 40.

[0060] The second groove 39 extends in an arc shape from the outer diameter end 38b side of the first groove 38 toward the downstream side of the rotation direction of the rotating shaft 1. The second groove 39 is formed such that its circumferential length is longer than its radial groove width.

[0061] The second groove 39 becomes shallower from the upstream side toward the downstream side in the direction of rotation of the rotation axis 1. Specifically, the bottom surface 39a of the second groove 39 extends linearly from the side wall of the first groove 38 to the land portion 40 (see, in particular). Figure 3 (b)). In addition, the bottom surface 39a of the second groove 39 can also be stepped.

[0062] The end portion 39b of the second groove portion 39 is positioned closer to the outer diameter side than the center of the radial width of the right surface 3a of the sealing ring 3. In other words, the end portion 39b of the second groove portion 39, which serves as a dynamic pressure generating portion, is positioned close to the outer diameter side of the right surface 3a of the sealing ring 3, i.e., the leakage area (L) side.

[0063] like Figure 3 As shown in (b), the depth D1 of the first groove 38 is deeper than the depth D2 of the second groove 39 (D1 > D2). Specifically, the depth D1 of the first groove 38 is approximately 25 times the depth D2 of the second groove 39. Furthermore, the depth D2 of the second groove 39 referred to here is the depth of its deepest part. Figure 3 In (b), for ease of explanation, the depth D2 of the second groove 39 is shown as larger than the actual depth.

[0064] The fluid recovery tank 37 is disposed between the end 39b of the second tank portion 39 and the sealed object area (H).

[0065] In detail, the fluid recovery tank 37 extends obliquely upstream of the rotation direction of the rotating shaft 1 from the inner diameter side toward the outer diameter side. In other words, the inner diameter end 37a of the fluid recovery tank 37, which is the downstream end of the relative rotation, is positioned closer to the inner diameter side, i.e., the sealing target area (H), than the outer diameter end 37b, which is the upstream end of the relative rotation.

[0066] When viewed axially, the fluid recovery tank 37 is formed in an arc shape that bulges outwards. The circumferential component of the fluid recovery tank 37 is larger than its radial component. Furthermore, the fluid recovery tank 37 is not limited to being arc-shaped when viewed axially; for example, it may also extend in a straight line when viewed axially.

[0067] The entire circumference of the fluid recovery tank 37 is enclosed by the land portion 40. That is, the fluid recovery tank 37 is not in communication with the dynamic pressure generating tank 36 and the sealed object area (H).

[0068] The outer diameter end 37b of the fluid recovery tank 37 is positioned closer to the inner diameter side than the center of the radial width of the right surface 3a of the sealing ring 3. In other words, the outer diameter end 37b of the fluid recovery tank 37 is positioned close to the inner diameter side of the right surface 3a of the sealing ring 3, i.e., the sealing target area (H) side.

[0069] The inner diameter end 37a of the fluid recovery tank 37 and the land portion 401 of the sealing target area (H) are radially divided by a radial width L1. In other words, the radial width L1 can also be described as the shortest distance between the fluid recovery tank 37 and the sealing target area (H).

[0070] Furthermore, the land portion 402 that divides the inner diameter end 37a of the fluid recovery tank 37 and the end portion 39b of the second tank portion 39 in the radial direction has a radial width L2.

[0071] The radial width L1 of the land portion 401 is smaller than the radial width L2 of the land portion 402 (L1 < L2). Furthermore, in this embodiment, the radial width L1 is approximately 1 / 30 times the radial width L2, but this can be freely varied. Preferably, the radial width L1 is approximately 1 / 2 to 1 / 50 times the radial width L2.

[0072] Furthermore, the radial width L1 of the land section 401 is smaller than the channel width L3 of the fluid recovery tank 37 (L1 < L3). In this embodiment, the radial width L1 is approximately 1 / 10 times the channel width L3, but this can be freely varied. Preferably, the radial width L1 is approximately 1 / 2 to 1 / 20 times the radial width L2.

[0073] Furthermore, referring to Figure 1 and Figure 3 (b) The depth D3 of the fluid recovery tank 37 is the same as the depth D1 of the first tank 38 (D1=D3).

[0074] In addition, in this embodiment, the depth D1 of the first groove 38 and the depth D3 of the fluid recovery groove 37 are approximately 25 times the depth D2 of the second groove 39, but can be freely changed. Preferably, the depth is about 5 to 50 times.

[0075] Furthermore, it is important that the dynamic pressure generating groove 36 generates dynamic pressure over a wide radial range on the right surface 3a. Therefore, as described above, the dynamic pressure generating groove 36 is positioned closer to the outer diameter side than the center of the radial width of the right surface 3a. On the other hand, the fluid recovery groove 37 only needs to suppress excessive pressure on the inner diameter side of the right surface 3a. Therefore, it only needs to be positioned closer to the inner diameter side than the dynamic pressure generating groove 36. As described above, the outer diameter end 37b is positioned closer to the inner diameter side than the center of the radial width of the right surface 3a of the sealing ring 3.

[0076] When the right surface 3a of the sealing ring 3 slides relative to the right surface 1a of the annular groove 1A, the oil in the dynamic pressure generating groove 36 moves toward the end 39b of the second groove 39, generating positive pressure at and near this end 39b. As a result, the right surface 3a of the sealing ring 3 slightly separates from the right surface 1a of the annular groove 1A (see reference). Figure 4 And an oil film is formed, thus reducing the friction between the right surface 3a of the sealing ring 3 and the right surface 1a of the annular groove 1A. In addition, oil is supplied from the sealing target area (H) to the second groove 39 via the first groove 38 at any time.

[0077] On the other hand, the oil in the fluid recovery tank 37 moves from the outer diameter end 37b toward the inner diameter end 37a, passes over the land portion 401 and is discharged into the sealed target area (H).

[0078] Thus, flow is generated within the fluid recovery tank 37 from the outer diameter end 37b toward the inner diameter end 37a, thereby recovering the fluid near the fluid recovery tank 37. Figure 4 As shown, it can reduce the pressure on the inner diameter side, i.e. the sealing target area (H) side, between the right surface 3a of the sealing ring 3 and the right surface 1a of the annular groove 1A in the positive pressure generated by the dynamic pressure generating groove 36.

[0079] Next, use Figure 4 The state of the sealing ring when the rotating shaft 1 rotates is described.

[0080] like Figure 1 As shown, when the equipment is operated, the fluid pressure in the sealing target area (H) becomes higher than that in the leakage area (L). Due to the fluid pressure in the sealing target area (H), the sealing ring 3 is subjected to a force in the expansion direction, and the outer peripheral surface 3b of the sealing ring 3 is pressed against the inner peripheral surface 2a of the housing 2. That is, the sealing ring 3 is fixed to the housing 2.

[0081] Furthermore, the right surface 3a of the sealing ring 3 is pressed against the right surface 1a of the annular groove 1A of the rotating shaft 1 by the fluid pressure of the sealing target area (H) and slides.

[0082] like Figure 4 As shown, when the right surface 3a of the sealing ring 3 slides relative to the right surface 1a of the annular groove 1A, dynamic pressure is generated by the dynamic pressure generating groove 36, and the right surface 3a of the sealing ring 3 slightly separates from the right surface 1a of the annular groove 1A. Furthermore, in Figure 4 For ease of explanation, the separation width between the right surface 3a of the sealing ring 3 and the right surface 1a of the annular groove 1A is shown to be larger than the actual width in the diagram.

[0083] The diameter of the right surface 3a of the sealing ring 3 is larger than the diameter of the right surface 1a of the annular groove 1A. No dynamic pressure generating groove 36 is provided on the portion of the right surface 3a of the sealing ring 3 that extends outward from the right surface 1a of the annular groove 1A. Therefore, on the right surface 3a of the sealing ring 3, a larger dynamic pressure acts on the inner diameter side compared to the outer diameter side. That is, a force acts on the sealing ring 3 such that it twists in a way that the inner diameter side of the right surface 3a of the sealing ring 3 is significantly further away from the right surface 1a of the annular groove 1A compared to the outer diameter side.

[0084] In detail, the sealing ring 3 exerts the following force: causing the right surface 3a of the sealing ring 3 to tilt relative to the right surface 1a of the annular groove 1A in such a way that the portion of the sealing ring 3 that is closer to the right surface 1a of the annular groove 1A is farther away from the right surface 1a of the annular groove 1A than the portion of the center point P of the sealing ring 3 on the inner diameter side and closer to the right surface 1a of the annular groove 1A than the portion of the center point P on the outer diameter side.

[0085] In this embodiment 1, a fluid recovery groove 37 is provided on the right surface 3a of the sealing ring 3, between the end 39b of the second groove portion 39 of the dynamic pressure generating groove 36 and the sealing target area (H). As a result, the pressure on the sealing target area (H) side of the positive pressure generated near the end 39b of the second groove portion 39 is opened to the sealing target area (H) through the fluid recovery groove 37, thereby suppressing the pressure on the sealing target area (H) side between the right surface 3a of the sealing ring 3 and the right surface 1a of the annular groove 1A.

[0086] Furthermore, the radial width L1 of the land portion 401 is smaller than the radial width L2 of the land portion 402. In other words, the fluid recovery tank 37 is disposed on the right surface 3a of the sealing ring 3, closer to the sealing target area (H). Therefore, it is easy to drain the oil in the fluid recovery tank 37 into the sealing target area (H). As a result, the oil in the fluid recovery tank 37 is immediately discharged from the inner diameter end 37a across the land portion 401 into the sealing target area (H), thus preventing dynamic pressure from easily generated near the inner diameter end 37a.

[0087] Furthermore, the radial width L1 of the land section 401 is smaller than the groove width L3 of the fluid recovery tank 37. Therefore, the fluid recovery tank 37 is configured close to the sealing target area (H), making it easier to discharge the oil in the fluid recovery tank 37 to the sealing target area (H).

[0088] Furthermore, the circumferential component of the fluid recovery tank 37 is greater than its radial component, meaning it is longer in the circumferential direction. Therefore, it is possible to recover fluid between the right surfaces 1a and 3a over a large circumferential range of the fluid recovery tank 37.

[0089] Furthermore, the inner diameter end 37a of the fluid recovery tank 37 is positioned closer to the sealing target area (H) than the outer diameter end 37b. The oil in the fluid recovery tank 37 flows from the outer diameter end 37b toward the inner diameter end 37a, thus enabling the oil in the fluid recovery tank 37 to be efficiently discharged to the sealing target area (H).

[0090] Furthermore, the fluid recovery tank 37 is a deep groove, which can prevent dynamic pressure from being generated near the inner diameter end 37a of the fluid recovery tank 37 between the right surface 3a of the sealing ring 3 and the right surface 1a of the annular groove 1A. Therefore, the pressure on the sealing target area (H) side can be reduced efficiently. Moreover, the fluid can be recovered entirely in the fluid recovery tank 37.

[0091] Furthermore, the dynamic pressure generating groove 36 has a first groove 38 and a second groove 39. The first groove 38 is a deep groove, so oil can be efficiently introduced from the first groove 38 to the second groove 39, thus the dynamic pressure generating effect of the second groove 39 is high.

[0092] Furthermore, the second groove 39 becomes shallower from the upstream side to the downstream side in the rotation direction of the rotating shaft 1, so that dynamic pressure can be generated efficiently through the wedge effect of the second groove 39.

[0093] Furthermore, the fluid recovery tank 37 is surrounded by the land area 40, meaning that the dynamic pressure generating tank 36 and the fluid recovery tank 37 are not in communication. Therefore, it is possible to avoid mutual obstruction between the flow of fluid in the dynamic pressure generating tank 36 and the flow of fluid in the fluid recovery tank 37 during relative rotation. Moreover, when stopped, the fluid recovery tank 37 is not easily affected by the sealing target area (H).

[0094] Furthermore, in this embodiment, the dynamic pressure generating groove 36 and the fluid recovery groove 37 are illustrated only on the right surface 3a of the sealing ring 3. However, it is also possible to provide the dynamic pressure generating groove and the fluid recovery groove on the left surface of the sealing ring 3 as well. Thus, for example, when from... Figure 1 When the pressure balance in both regions reverses, the sealing ring 3 moves to the left, and its left surface contacts and slides against the left surface of the annular groove 1A. This allows it to generate dynamic pressure in the dynamic pressure generating groove on the left side and recover fluid in the fluid recovery groove on the left side. Furthermore, it can be assembled regardless of the orientation, enabling highly efficient operation.

[0095] Furthermore, in this embodiment, the depth of the second groove portion 39 of the dynamic pressure generating groove 36 is shown to gradually become shallower from the upstream side of relative rotation toward the downstream side of relative rotation, but the depth may also be constant.

[0096] Furthermore, in this embodiment, the depth of the fluid recovery tank 37 is shown to be the same as the depth of the first groove portion 38 of the dynamic pressure generating tank 36, but the depths of the first groove portion 38 and the dynamic pressure generating tank 36 may also be different. For example, the fluid recovery tank may be a shallow tank, and when rotating relative to each other, a relative negative pressure may be generated in the fluid recovery tank to improve the fluid recovery effect of the fluid recovery tank.

[0097] Example 2

[0098] Next, refer to Figure 5 The sealing ring of Example 2 will be described. Furthermore, repeated structural descriptions identical to those of Example 1 described above will be omitted.

[0099] like Figure 5As shown, in this embodiment 2, a dynamic pressure generating groove 236 and a fluid recovery groove 237 are provided on the right surface 203a of the sealing ring 203. The dynamic pressure generating groove 236 has the same structure as the dynamic pressure generating groove 36 in embodiment 1.

[0100] The fluid recovery tank 237 extends circumferentially, approximately parallel to the inner circumferential surface of the sealing ring 203. The fluid recovery tank 237 is disposed between the second groove portion 239 of the dynamic pressure generating groove 236 and the sealing target area (H), closer to the sealing target area (H).

[0101] As a result, the fluid recovery tank 237 is close to the sealing target area (H) over a large area in the entire circumferential range, so the fluid in the fluid recovery tank 237 can easily be discharged to the sealing target area (H).

[0102] Furthermore, in this embodiment, the fluid recovery tank 237 is shown to be arranged circumferentially parallel, but it can also be arranged tilted or deformed so that the downstream end of the relatively rotating side approaches the sealing target area (H). This allows the fluid flow direction to be directed towards the sealing target area (H), enabling more efficient fluid recovery and discharge.

[0103] Example 3

[0104] Next, refer to Figure 6 The sealing ring of Example 3 will be described. Furthermore, repeated structural descriptions identical to those of Example 1 described above will be omitted.

[0105] like Figure 6 As shown, in this embodiment 3, a dynamic pressure generating groove 336 and a fluid recovery groove 337 are provided on the right surface 303a of the sealing ring 303. The dynamic pressure generating groove 336 has the same structure as the dynamic pressure generating groove 36 in embodiment 1.

[0106] When viewed along the axial direction, the fluid recovery tank 337 is rectangular in shape. Multiple fluid recovery tanks 337 are arranged circumferentially between the second groove portion 339 of the dynamic pressure generating groove 336 and the sealing target area (H), close to the sealing target area (H). In this embodiment 3, three are arranged.

[0107] In this way, multiple fluid recovery tanks 337 can be set relative to a single dynamic pressure generating tank 336.

[0108] Furthermore, in this embodiment, multiple fluid recovery tanks 337 are shown arranged parallel to each other in the circumferential direction. However, they can also be arranged at an angle or in a stepped manner so that the downstream end of the relative rotation is close to the sealing target area (H). This allows the fluid flow direction to be directed towards the sealing target area (H), enabling more efficient fluid recovery and discharge.

[0109] Example 4

[0110] Next, refer to Figure 7 The sealing ring of Example 4 will be described. Furthermore, repeated structural descriptions identical to those of Example 3 described above will be omitted.

[0111] like Figure 7 As shown, on the right surface 403a of the sealing ring 403 in this embodiment 4, a plurality of fluid recovery tanks 437 are provided relative to a dynamic pressure generating tank 436. In this embodiment 4, four fluid recovery tanks 437 are provided.

[0112] When viewed along the axial direction, the fluid recovery tank 437 of this embodiment 4 has an elliptical shape that is longer in the radial direction.

[0113] In this way, the shape of the fluid recovery tank 437 can be freely changed. In addition, the fluid recovery tank is not limited to an elliptical shape, but can also be a circular shape, etc.

[0114] Furthermore, in this embodiment, multiple fluid recovery tanks 437 are shown arranged parallel to each other in the circumferential direction. However, they can also be arranged at an angle or in a stepped manner so that the downstream end of the relative rotation is close to the sealing target area (H). This allows the fluid flow direction to be directed towards the sealing target area (H), enabling more efficient fluid recovery and discharge.

[0115] Example 5

[0116] Next, refer to Figure 8 The sealing ring of Example 5 will be described. Furthermore, repeated structural descriptions identical to those of Example 1 described above will be omitted.

[0117] like Figure 8 As shown, in this embodiment 5, a dynamic pressure generating groove 536 and a fluid recovery groove 537 are provided on the right surface 503a of the sealing ring 503. The dynamic pressure generating groove 536 and the fluid recovery groove 537 have the same structure as the dynamic pressure generating groove 36 and the fluid recovery groove 37 in embodiment 1.

[0118] A circumferentially extending groove 510 is provided in the land portion 540 between the inner diameter end 537a of the fluid recovery tank 537 on the right surface 503a of the sealing ring 503 and the sealing target area (H). Fluid can be easily discharged to the sealing target area (H) side using the groove 510 provided between the inner diameter end 537a of the fluid recovery tank 537 and the sealing target area (H).

[0119] Thus, even though a groove 510 is provided between the inner diameter end 537a of the fluid recovery tank 537 and the sealing target area (H), the fluid recovery tank 537 and the sealing target area (H) are not connected because the inner diameter end 537a of the fluid recovery tank 537 and the sealing target area (H) are separated by the remaining land portion 540.

[0120] Example 6

[0121] Next, refer to Figure 9 The sealing ring of Example 6 will be described. Furthermore, repeated structural descriptions identical to those of Example 1 described above will be omitted.

[0122] like Figure 9 As shown, in this embodiment 6, a dynamic pressure generating groove 636 and a fluid recovery groove 637 are provided on the right surface 503a of the sealing ring 603. The dynamic pressure generating groove 636 and the fluid recovery groove 637 have the same structure as the dynamic pressure generating groove 36 and the fluid recovery groove 37 in embodiment 1.

[0123] A plurality of recesses 610 are provided in the land portion 640 between the inner diameter end 637a of the fluid recovery tank 637 on the right surface 603a of the sealing ring 603 and the sealing target area (H). Fluid can be easily discharged to the sealing target area (H) side using the plurality of recesses 610 provided between the inner diameter end 637a of the fluid recovery tank 637 and the sealing target area (H).

[0124] Thus, even though a recess 610 is provided between the inner diameter end 637a of the fluid recovery tank 637 and the sealing target area (H), the fluid recovery tank 637 and the sealing target area (H) are not connected because the inner diameter end 637a of the fluid recovery tank 637 and the sealing target area (H) are separated by the remaining land portion 640.

[0125] That is, as long as the fluid recovery tank 637 is not connected to the sealed object area (H) via the recess 610.

[0126] Example 7

[0127] Next, refer to Figure 10 The sealing ring of Example 7 will be described. Furthermore, repeated structural descriptions identical to those of Example 1 described above will be omitted.

[0128] like Figure 10 As shown, in the sealing ring 703 of this embodiment, the right surface 703a, which serves as the setting surface, is pressed against the right surface 1a of the annular groove 1A of the rotating shaft 1 by fluid pressure, and rotates together with the rotating shaft 1.

[0129] The sealing ring 703 has a dynamic pressure generating groove 736 and a fluid recovery groove 737 formed on its outer peripheral surface 703b, which serves as a sliding surface. The dynamic pressure generating groove 736 and the fluid recovery groove 737 communicate with the sealing target area (H) on the opposite side of the right surface 703a on the outer peripheral surface 703b.

[0130] When the sealing ring 703 rotates together with the rotating shaft 1, the outer peripheral surface 703b of the sealing ring 703 slides with the inner peripheral surface 2a of the housing 2, generating dynamic pressure in the dynamic pressure generating groove 736, and the outer peripheral surface 703b of the sealing ring 703 separates from the inner peripheral surface 2a of the housing 2 to form an oil film.

[0131] At this time, at the position of the specific dynamic pressure generating groove 736 on the side near the sealing target area (H), the fluid between the outer peripheral surface 703b of the sealing ring 703 and the inner peripheral surface 2a of the housing 2 is recovered by the fluid recovery groove 737, the pressure on the sealing target area (H) side is reduced, so the tilting of the outer peripheral surface 703b of the sealing ring 703 and the inner peripheral surface 2a of the housing 2 can be suppressed.

[0132] Example 8

[0133] Next, refer to Figure 11 The sealing ring of Example 8 will be described. Furthermore, repeated structural descriptions identical to those of Example 1 described above will be omitted.

[0134] like Figure 11 As shown, in the shaft sealing device of this embodiment 8, an annular groove 82A is formed in the housing 82, and a sealing ring 803 is disposed in the annular groove 82A. In addition, the outer peripheral surface 81a of the rotating shaft 81 extends flatly along the axial direction.

[0135] The inner circumferential surface 803d of the sealing ring 803, which serves as the mounting surface, is pressed against the outer circumferential surface 81a of the rotating shaft 81 by fluid pressure, and rotates together with the rotating shaft 81.

[0136] Furthermore, the right surface 803a of the sealing ring 803, which serves as the sliding surface, comes into contact with the right surface 82a of the annular groove 82A through fluid pressure, and can slide relative to each other.

[0137] A dynamic pressure generating groove 836 and a fluid recovery groove 837 are formed on the right surface 803a of the sealing ring 803. The dynamic pressure generating groove 836 and the fluid recovery groove 837 communicate with the sealing target area (H) on the opposite side of the inner peripheral surface 803d on the right surface 803a.

[0138] When the sealing ring 803 rotates together with the rotating shaft 81, the right surface 803a of the sealing ring 803 slides with the right surface 82a of the annular groove 82A, generating dynamic pressure in the dynamic pressure generating groove 836, and the right surface 803a of the sealing ring 803 separates from the right surface 82a of the annular groove 82A to form an oil film.

[0139] At this time, at the position of the specific dynamic pressure generating groove 836 on the side near the sealing target area (H), the fluid between the right surface 803a of the sealing ring 803 and the right surface 82a of the annular groove 82A is recovered by the fluid recovery groove 837, the pressure on the sealing target area (H) side decreases, and thus the tilting of the right surface 803a of the sealing ring 803 and the right surface 82a of the annular groove 82A can be suppressed.

[0140] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the specific structure is not limited to these embodiments, and changes and additions that do not depart from the spirit of the present invention are also included in the present invention.

[0141] For example, in the aforementioned embodiments 1 to 8, the sliding surface of the sealing ring is shown to be perpendicular to the setting surface, but it is not limited to the sliding surface and the setting surface extending in the intersecting direction.

[0142] Furthermore, in the aforementioned embodiments 1 to 8, the method of rotating the shaft relative to the housing was illustrated, but it is also possible that the housing rotates relative to the shaft, or that both the shaft and the housing rotate in the relative rotation direction.

[0143] Furthermore, in the aforementioned embodiments 1, 2, 5, and 6, the circumferential component of the fluid recovery mechanism is shown to be larger than the radial component, but it is also possible for the radial component to be larger than the circumferential component.

[0144] Furthermore, in the aforementioned embodiments 1 to 8, the dynamic pressure generating mechanism is illustrated as being composed of a fluid inlet groove and a dynamic pressure generating groove, but for example, it could also be a spiral groove, etc.

[0145] Furthermore, in the aforementioned embodiments 1 to 8, a method was illustrated where the depth of the fluid recovery mechanism is constant, but the depth can also be varied. For example, it can also be as follows: Figure 12 As shown, the fluid recovery tank 937 gradually becomes shallower from the inner diameter end 937a toward the outer diameter end 937b. This creates a relative negative pressure at the outer diameter end 937b on the upstream side of the fluid recovery tank 937 during relative rotation, making it easier to collect fluid between the sliding surfaces. Furthermore, since the inner diameter end 937a of the fluid recovery tank 937 is a deep groove, dynamic pressure is less likely to be generated near the inner diameter end 937a.

[0146] Label Explanation

[0147] 1: Rotating shaft (shaft); 1A: Annular groove; 1a: Right surface (sliding surface); 2: Housing; 2a: Inner circumferential surface (setting surface); 3: Sealing ring; 3a: Right surface (sliding surface); 3b: Outer circumferential surface (setting surface); 36: Dynamic pressure generating groove (dynamic pressure generating mechanism); 37: Fluid recovery groove (fluid recovery mechanism); 37a: Inner diameter end (end on the downstream side of the relative rotation); 37b: Outer diameter end (end on the upstream side of the relative rotation); 38: First groove (fluid inlet groove); 39: Second groove (dynamic pressure generating groove); 39b: End (dynamic pressure generating part); 40: Land section; 401: Land section; 402: Land section.

Claims

1. A sealing ring, comprising: A sliding surface that rotates and slides relative to the shaft or the housing through which the shaft is inserted; and A surface is provided, which intersects with the sliding surface, and is located on the other side of the shaft and the housing. The sealing ring divides the space between one side of the sliding surface that intersects with the setting surface and the other side of the sliding surface that intersects with the setting surface. in, The sliding surface is provided with: A dynamic pressure generating mechanism, which communicates with one of the spaces and has a dynamic pressure generating section; and A fluid recovery mechanism is disposed between the dynamic pressure generating unit and the space.

2. The sealing ring according to claim 1, wherein, The fluid recovery mechanism is positioned on the side closer to the space in question.

3. The sealing ring according to claim 1, wherein, The width of the land portion between the fluid recovery mechanism and the space is smaller than the width of the fluid recovery mechanism.

4. The sealing ring according to claim 1, wherein, The fluid recovery mechanism is relatively long in the circumferential direction.

5. The sealing ring according to claim 1, wherein, The fluid recovery mechanism is configured such that the downstream end rotates relative to the space side.

6. The sealing ring according to claim 1, wherein, The depth of the fluid recovery mechanism becomes shallower from the downstream side of the relative rotation toward the upstream side of the relative rotation.

7. The sealing ring according to claim 1, wherein, The fluid recovery mechanism is a deep tank.

8. The sealing ring according to any one of claims 1 to 7, wherein, The dynamic pressure generating mechanism consists of a fluid inlet channel and a dynamic pressure generating channel. The fluid inlet channel is connected to one of the spaces, and the dynamic pressure generating channel extends circumferentially from the fluid inlet channel and is shallower than the fluid inlet channel.

9. The sealing ring according to claim 8, wherein, The dynamic pressure generating groove becomes shallower from the upstream side of the relative rotation toward the downstream side of the relative rotation.

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