sliding member

Abstract

The purpose is to provide a sliding component with low starting torque during startup. A sliding component (10) is disposed in a relatively rotating part of a rotating machine and slides relative to other sliding components (20), wherein the sliding component (10) is provided with: a storage space (16) formed on the back side of the sliding surface (11) of the sliding component (10) for the introduction of fluid (F); and a plurality of through holes (17) communicating with the storage space (16) and the sliding surface (11).

Description

Technical Field

[0001] This invention relates to sliding components that rotate relative to each other, such as sliding components used in shaft sealing devices for sealing rotating shafts of rotating machinery in the fields of automobiles, general industrial machinery or other sealing applications, or sliding components used in bearings of machinery in the fields of automobiles, general industrial machinery or other bearing applications. Background Technology

[0002] As a shaft sealing device to prevent leakage of the sealed fluid, a mechanical seal, for example, has a pair of annular sliding parts that rotate relative to each other and whose sliding surfaces slide against each other. While such a mechanical seal can seal high-pressure sealed fluid, it is desirable to further reduce leakage of the sealed fluid and improve the lubrication of the sliding parts.

[0003] For example, the mechanical seal shown in Patent Document 1 is configured as a pair of annular sliding components that can rotate relative to each other, and is provided with a through hole communicating with a groove provided on the sliding surface of one of the sliding components. This mechanical seal provides fluid from the groove to the sliding surface through the through hole, and the force acting by the hydrostatic pressure of the fluid in the direction that separates the sliding surfaces of the pair of sliding components from each other reduces leakage and provides excellent lubrication.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: International Publication No. 00 / 75540 (Page 5, Figure 2) Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] In a sliding component like that in Patent Document 1, although a groove extending circumferentially from the opening of the through hole can provide fluid across the entire circumferential range between the sliding surfaces, the pressure of the fluid within the groove is uneven in the circumferential direction, and the fluid film formed between the sliding surfaces is prone to becoming uneven in the circumferential direction. Therefore, especially during low-speed startup, it may locally become poor lubrication, causing increased torque, wear on the sliding surfaces, etc.

[0009] This invention was made in view of such a problem, and its purpose is to provide a sliding component with low starting torque during startup.

[0010] Methods for solving problems

[0011] To address the aforementioned issues, the sliding component of the present invention is disposed at a relatively rotating part of a rotating machine and slides relative to other sliding components. The sliding component is provided with: a storage space formed on the back side of the sliding surface of the sliding component for fluid introduction; and a plurality of through holes communicating with the storage space and the sliding surface.

[0012] Therefore, during the startup of rotating machinery, fluid is supplied between the sliding surfaces from the same storage space formed on the back side of the sliding surfaces through multiple through holes. As a result, static pressure acts evenly circumferentially between the sliding surfaces, thus reducing the starting torque during startup. Furthermore, the configuration and shape of the multiple through holes can be easily modified to accommodate the pressure and quantity requirements of the fluid supplied between the sliding surfaces.

[0013] Alternatively, the storage space may be continuous and annular in the circumferential direction of the sliding component.

[0014] As a result, the fluid introduced into the storage space is at approximately the same pressure. Therefore, fluid at approximately the same pressure is supplied from multiple through holes to the sliding surfaces.

[0015] Alternatively, the storage space can be a continuous cavity in the circumferential direction of the radial cross-section of the sliding component.

[0016] Therefore, the sliding component is cylindrical with continuous cavities in the circumferential direction, so the storage space is not easily affected by the external environment of the sliding component, such as external fluids.

[0017] Alternatively, the through hole may extend in a straight line.

[0018] This enables the efficient supply of fluid from the storage space to the sliding surfaces.

[0019] Alternatively, the through hole may extend perpendicularly to the sliding surface.

[0020] This allows the hydrostatic pressure of the fluid to act efficiently from the storage space to the sliding surface.

[0021] Alternatively, the opening on the sliding surface side of the through hole may be flush with the sliding surface.

[0022] Therefore, the opening on the sliding side of the through hole does not extend in the surface direction, so the through hole does not generate dynamic pressure during startup or normal operation, and is easy to maintain the initial pressure between the sliding surfaces.

[0023] Alternatively, a dynamic pressure generating groove may be provided on the sliding surface.

[0024] This allows for a reduction in drive torque from startup to normal operation.

[0025] Alternatively, the sliding component may be a sliding component on the stationary side.

[0026] Therefore, it does not rotate during startup or normal operation, so the fluid in the storage space does not easily flow, and fluid can be stably supplied from the storage space to the through hole.

[0027] Alternatively, the fluid may be a sealed fluid.

[0028] Therefore, it is not easy for other fluids besides the fluid on the leaking side to mix into the sealed fluid. Attached Figure Description

[0029] Figure 1 This is a cross-sectional view of the mechanical seal of the sliding component of Embodiment 1 of the present invention.

[0030] Figure 2 This is a perspective view showing a portion of the sliding component of Embodiment 1 of the present invention cut open.

[0031] Figure 3 This is a front view of the sliding component of Embodiment 1 of the present invention.

[0032] Figure 4 This is a radial cross-sectional view of the sliding component of Embodiment 1 of the present invention.

[0033] Figure 5 This is a radial cross-sectional view showing a modified example of the sliding member of Embodiment 1 of the present invention.

[0034] Figure 6 (a) is a front view showing the sliding component of Embodiment 2 of the present invention. Figure 6 (b) is a radial sectional view of the sliding component.

[0035] Figure 7 (a) is a front view showing the sliding component of Embodiment 3 of the present invention. Figure 7 (b) is a radial sectional view of the sliding component.

[0036] Figure 8 This is a front view of the sliding component of Embodiment 4 of the present invention.

[0037] Figure 9 It is along Figure 8 A cross-sectional view along line AA.

[0038] Figure 10 It is along Figure 8 A cross-sectional view of the BB line.

[0039] Figure 11 This is a radial cross-sectional view illustrating another embodiment 1 of the sliding component of the present invention.

[0040] Figure 12 This is a radial cross-sectional view illustrating another embodiment 2 of the sliding component of the present invention. Detailed Implementation

[0041] Hereinafter, the method of implementing the sliding component of the present invention will be described based on embodiments.

[0042] Example 1

[0043] Reference Figures 1-5 A mechanical seal using the sliding member of Example 1 will be described. In this embodiment, the outer diameter side of the sliding member constituting the mechanical seal will be described as the sealed fluid side, and the inner diameter side as the atmospheric side. Furthermore, the sliding surface side of the sliding member will be described as the front side, and the side opposite to the sliding surface will be described as the back side.

[0044] Figure 1 The mechanical seal M shown is an inner-type mechanical seal that seals against leakage of the high-pressure fluid F from the outer diameter side to the atmosphere A on the inner diameter side. The fluid F can be either a liquid or a gas.

[0045] The mechanical seal M mainly consists of a stationary sealing ring 10, which is a circular sliding component, and a rotary sealing ring 20, which is another circular sliding component. The stationary sealing ring 10 is disposed in a non-rotating state and is axially movable within sealing covers 4 and 5, which are fixed to the housing of the mounted equipment. The rotary sealing ring 20 is mounted on the rotating shaft 1 via a sleeve 2 and can rotate integrally with the rotating shaft 1. Furthermore, the mechanical seal M utilizes a helical spring 7 to apply axial force to the stationary sealing ring 10, causing the sliding surface 11 of the stationary sealing ring 10 and the sliding surface 21 of the rotary sealing ring 20 to slide in close contact. While the sliding surface 21 of the rotary sealing ring 20 is flat, it may also have grooves or the like.

[0046] The stationary sealing ring 10 and the rotating sealing ring 20 are typically formed from a combination of SiC (hard material) and SiC (hard material) or a combination of SiC (hard material) and carbon (soft material). However, they are not limited to these; any sliding material suitable for use in mechanical seals can be used. For example, as a hard material, ceramics other than SiC, carbon, metals, resins, surface-modified materials (coatings), composite materials, etc., can also be used.

[0047] Reference Figures 2-4The stationary sealing ring 10 is an annular body with an annular cavity forming an internal storage space 16. Furthermore, the stationary sealing ring 10 is formed to be circular in top view and has a rectangular frame-like radial cross-section. The stationary sealing ring 10 is manufactured using a layer-by-layer molding method that utilizes a 3D printer as an additive manufacturing device, but it can also be manufactured using other methods.

[0048] The stationary sealing ring 10 has an annular front sidewall portion 12, a cylindrical outer diameter sidewall portion 13, an annular back sidewall portion 14, and a cylindrical inner diameter sidewall portion 15. The front sidewall portion 12 has a sliding surface 11. The outer diameter sidewall portion 13 extends axially, substantially perpendicular to the outer diameter end of the front sidewall portion 12. The back sidewall portion 14 is substantially perpendicular to the back diameter end of the outer diameter sidewall portion 13 and is positioned opposite the front sidewall portion 12. The inner diameter sidewall portion 15 extends axially, substantially perpendicular to the inner diameter end of the back sidewall portion 14 and the inner diameter end of the front sidewall portion 12.

[0049] In this embodiment, the portions of walls 13-15 facing the storage space 16 are formed with approximately the same thickness. Furthermore, the thickness of the front sidewall 12 is greater than the thickness of walls 13-15.

[0050] Furthermore, a storage space 16 is formed in the stationary sealing ring 10, which is divided by the wall portions 12-15 and is continuous in the circumferential direction. The storage space 16 is annular and rectangular in cross-section. The radial flow path cross-sectional area of ​​the storage space 16 is approximately the same and continuous in the circumferential direction.

[0051] like Figures 2-4 As shown, a plurality of through holes 17 are formed in the front sidewall portion 12. The through holes 17 penetrate the front sidewall portion 12 substantially perpendicular to the sliding surface 11, and communicate with the storage space 16 and the sliding surface 11 respectively. Each through hole 17 is a straight line extending axially and is circular in top view. In addition, the radial flow path cross-sectional area of ​​each through hole 17 is approximately the same, and each through hole 17 is continuous axially from the storage space 16 to the opening 17a.

[0052] In the plurality of through holes 17, adjacent through holes 17 in the circumferential direction are arranged at predetermined radial intervals, i.e., an alternating arrangement is adopted. Furthermore, the plurality of through holes 17 are arranged on the radial outer diameter side of the sliding surface 11. The through holes 17 are formed simultaneously with the stationary sealing ring 10 using a 3D printer, but can also be formed by drilling, laser, or other methods.

[0053] In addition, such as Figure 3 , Figure 4As shown, the opening 17a on the sliding surface 11 side of the through hole 17 is formed flush with the sliding surface 11. Moreover, the axial dimensions of each through hole 17 are approximately the same.

[0054] A pressure inlet portion 18 is formed in the outer diameter sidewall portion 13. The pressure inlet portion 18 is a through hole that extends along the thickness direction.

[0055] Next, refer to Figure 1 , Figure 2 The supply of the sealed fluid F to the sliding surfaces 11 and 21 during the stopping, starting, and normal operation of the rotating equipment using the mechanical seal M is described.

[0056] Reference Figure 1 When the rotating equipment stops, i.e., when the rotating shaft 1 stops, the sum of the force of the helical spring 7 and the pressing force generated by the pressure of the sealed fluid F acts in the direction that brings the sliding surfaces 11 and 21 closer together. On the other hand, the opening 17a of the through hole 17 faces the sliding surface 21, and the force generated by the static pressure of the sealed fluid F acts in the direction that separates the sliding surfaces 11 and 21.

[0057] Since the force in the direction that brings sliding surfaces 11 and 21 closer together is greater than the force in the direction that separates sliding surfaces 11 and 21, sliding surfaces 11 and 21 come into contact. This prevents the sealed fluid F from leaking into the atmosphere A.

[0058] In addition, there is some sealed fluid F between the sliding surfaces 11 and 21 when they stop, and the sealed fluid F not only enters from the outer diameter end of the sliding surfaces 11 and 21, but also easily enters from each through hole 17 due to capillary phenomena, etc.

[0059] Furthermore, since multiple through holes 17 are formed approximately equally over the entire circumferential range of the sliding surface 11, the sealed fluid F can be provided approximately equally over the entire circumferential range between the sliding surfaces 11 and 21.

[0060] In addition, such as Figure 2 As indicated by the thin black arrow, the sealed fluid F is supplied into the storage space 16 through the pressure inlet 18. Therefore, the flow direction of the sealed fluid F does not easily affect the flow through the through hole 17 directly from the pressure inlet 18. Moreover, it is possible to achieve a state where the storage space 16 is stably filled with the sealed fluid F.

[0061] When the rotating equipment is stationary and during startup, images are obtained through each of the 17 through holes. Figure 2The sealed fluid F is provided as indicated by the thick black arrow in the middle, so that the sealed fluid F flows slightly out between the sliding surfaces 11 and 21. In this way, when stationary and during low-speed rotation at startup, the static pressure of the sealed fluid F acts from the through hole 17 onto the sliding surface 21, and the sealed fluid F is provided between the sliding surfaces 11 and 21, so that the load on the sliding surfaces is appropriately reduced and the lubrication is excellent.

[0062] Subsequently, the rotational speed of the rotating shaft 1 increases, even to the rotational speed during normal operation of the rotating equipment, and the static pressure of the sealed fluid F is applied from the through hole 17 to the sliding surface 21, so that the sealed fluid F can be supplied through each through hole 17, and the sealed fluid F flows out between the sliding surfaces 11 and 21.

[0063] As explained above, regarding the stationary sealing ring 10 of this embodiment 1, since the storage space 16 is a continuous annular shape in the circumferential direction, the sealed fluid F introduced into the storage space 16 has a substantially uniform pressure. Therefore, the sealed fluid F is supplied with a substantially uniform pressure from the plurality of through holes 17 to the sliding surfaces 11, 21.

[0064] Furthermore, regarding the storage space 16, only the thickness of the front sidewall portion 12 exists between the sliding surface 11 and the storage space 16, meaning that the storage space 16 is disposed directly below the sliding surface 11. As a result, the pressure loss of the sealed fluid F supplied from the storage space 16 to the sliding surface 11 through the through hole 17 is minimal.

[0065] Furthermore, the storage space 16 is divided by walls 12-15 that are rectangular in shape when viewed radially. Also, the storage space 16 is a continuous cavity in the radial section. In other words, the stationary sealing ring 10 is cylindrical with a continuous cavity in the circumferential direction, so the storage space 16 is less susceptible to the influence of the external environment of the stationary sealing ring 10, such as turbulence of the sealed fluid F outside the stationary sealing ring 10, and the pressure within the storage space 16 is easily maintained at approximately the same level.

[0066] Furthermore, the radial flow path cross-sectional area of ​​the storage space 16 is approximately the same, and the storage space 16 is continuous in the circumferential direction. Therefore, compared with structures where the radial flow path cross-sectional area varies, it is easier to keep the pressure within the storage space 16 approximately the same throughout the entire circumferential direction.

[0067] Furthermore, only one pressure inlet 18 is formed. Therefore, compared to a structure with multiple inlets, the impact of supplying the sealed fluid F into the storage space 16 can be reduced.

[0068] Furthermore, the through-hole 17 extends in a straight line, which reduces pressure loss compared to a structure that extends in a zigzag or curved shape. Therefore, the sealed fluid F can be efficiently supplied from the storage space 16 to the sliding surfaces 11 and 21.

[0069] Furthermore, the through hole 17 is formed into a circular shape when viewed in cross-section. Therefore, compared to a structure formed into a polygonal shape when viewed in cross-section, pressure loss can be reduced.

[0070] Furthermore, the cross-sectional area of ​​the flow path 17 is approximately the same throughout the entire extension direction. Therefore, compared to structures with varying flow path cross-sectional areas, pressure loss can be reduced.

[0071] Furthermore, since the axial dimensions of each through-hole 17 are approximately the same, the pressure loss generated when the sealed fluid F passes through the through-hole 17 is approximately the same. As a result, it is easy to make the static pressure of the sealed fluid F flowing out of each through-hole 17 approximately the same.

[0072] Furthermore, the inner circumferential surface 17b of each through hole 17 extends axially perpendicular to the sliding surface 11, thus reducing pressure loss compared to a structure where the inner circumferential surface of the through hole extends obliquely relative to the sliding surface 11. Therefore, it is easy to make the pressure and flow rate of the sealed fluid F supplied through each through hole 17 approximately the same.

[0073] As a result, the circumferential pressure distribution between sliding surfaces 11 and 21 is approximately equal. Therefore, the relative rotation of the stationary sealing ring 10 and the rotating sealing ring 20 can be stabilized.

[0074] Furthermore, the through hole 17 extends perpendicularly to the sliding surface 11. Therefore, compared to a structure where the through hole is inclined relative to the sliding surface 11, it is easier to apply static pressure in a direction that is approximately perpendicular to the sliding surface 21 of the rotary sealing ring 20, that is, in the same direction as the direction in which the sliding surfaces 11 and 21 are separated from each other. As a result, the static pressure of the sealed fluid F can be applied efficiently from the storage space 16 between the sliding surfaces 11 and 21.

[0075] In addition, the opening 17a of the through hole 17 is formed to be flush with the sliding surface 11. For example, the groove extending in the circumferential direction is not connected at the opening of the through hole. Therefore, the through hole 17 does not generate dynamic pressure when rotating at high speed during normal operation, and is easy to maintain the initial pressure between the sliding surfaces 11 and 21.

[0076] Furthermore, the stationary sealing ring 10, which forms the storage space 16, the through hole 17, and the pressure inlet 18, is set in a stationary state without rotation. During startup, the stationary sealing ring 10 does not rotate during the relative rotation during normal operation, so the sealed fluid F in the storage space 16 is not easily generated to flow, and the sealed fluid F can be stably supplied from the storage space 16 to the through hole 17.

[0077] Furthermore, each through hole 17 is formed on the outer diameter side of the sliding surface 11. Compared to a structure where each through hole 17 is formed on the inner diameter side of the sliding surface 11, the separation distance from each through hole 17 to the atmosphere A side is longer. As a result, not only can leakage of the sealed fluid F be prevented, but the area where the sealed fluid F can be provided can also be expanded radially.

[0078] In addition, since the configuration and shape of the multiple through holes 17 can be easily changed, it is easy to meet the pressure and quantity requirements of the fluid supplied between the sliding surfaces 11 and 21.

[0079] Furthermore, the through holes 17 are staggered. Therefore, compared to a structure where the same number of through holes as in this embodiment are arranged circumferentially on a circle, adjacent through holes 17 can be arranged close to each other. Thus, multiple through holes 17 can be arranged while maintaining the structural strength of the stationary sealing ring 10. In addition, because the through holes 17 can be arranged closely, the circumferential pressure balance between the sliding surfaces 11 and 21 is good.

[0080] Furthermore, each through hole 17 is a through hole formed in the front sidewall portion 12. Therefore, compared with a structure that additionally installs orifices on the stationary sealing ring 10, the construction can be simplified.

[0081] Additionally, the pressure inlet 18 is configured to be located on the lower side in the vertical direction within the mechanical seal M (see reference). Figure 1 Therefore, even if the sealed fluid F contains dust or the like, it is not easy for it to enter the storage space 16 through the pressure inlet 18. Furthermore, even if the sealed fluid F containing dust or the like does enter the storage space 16, it easily sinks due to gravity and is discharged from the pressure inlet 18. This prevents the through hole 17 from becoming blocked. In addition, the stationary sealing ring 10 is installed in a non-rotating, stationary state. This maintains the position of the pressure inlet 18.

[0082] Furthermore, in this embodiment, the structure of the pressure inlet portion 18 formed on the outer diameter sidewall portion 13 of the stationary sealing ring 10 has been described, but it is not limited to this, and other structures may also be described as follows. Figure 5 As shown in the static sealing ring 10A, the pressure inlet 118 is formed on the back side wall portion 14, but this can be modified as appropriate.

[0083] Alternatively, multiple pressure inlet portions 18 or 118 may be formed in the stationary sealing ring. For example, one pressure inlet portion 18 and multiple pressure inlet portions 118 may be formed respectively.

[0084] Furthermore, the axial dimension of the through hole 17, or in other words, the thickness of the front sidewall portion 12, can be appropriately changed. Therefore, the static pressure of the sealed fluid F supplied between the sliding surfaces 11 and 21 can be adjusted by utilizing the pressure loss of the sealed fluid F as it passes through the through hole 17.

[0085] Example 2

[0086] Next, refer to Figure 6 Example 2 of the sliding component will be described. Furthermore, descriptions of structures identical to those in Example 1 described above will be omitted.

[0087] like Figure 6 As shown in (a), a plurality of through holes 171, 172, 173 and 174 are formed on the stationary sealing ring 110 from the outer diameter side toward the inner diameter side.

[0088] like Figure 6 As shown in (b), the back side 121 of the front sidewall portion 120 is inclined, and the thickness of the front sidewall portion 120 gradually increases from the outer diameter side to the inner diameter side. Therefore, among the axial dimensions of the through holes 171 to 174, through hole 171 is the shortest. Furthermore, through holes 172 and 173 successively increase in length, with through hole 174 being the longest.

[0089] Therefore, in the stationary sealing ring 110, compared with the stationary sealing ring 10 of Embodiment 1 described above, through holes 171 to 174 are formed in a wider region in the radial direction. As a result, the sealed fluid F can be supplied more stably between the sliding surfaces 111 and 21.

[0090] Furthermore, the axial dimensions of the through holes 171-174 increase towards the inner diameter side. Consequently, the pressure loss is greater closer to the inner diameter side. In other words, the static pressure of the sealed fluid F supplied to the sliding surfaces 111 and 21 through the through holes closer to the inner diameter side is lower, thus the static pressure of the sealed fluid F between the sliding surfaces 111 and 21 is greater on the outer diameter side than on the inner diameter side. This achieves a balance between reducing leakage and improving lubrication.

[0091] Example 3

[0092] Next, refer to Figure 7 Example 3 of the sliding component will be described. Furthermore, descriptions of structures identical to those in Examples 1 and 2 described above will be omitted.

[0093] like Figure 7As shown, a plurality of helical dynamic pressure generating grooves 19 are formed on the sliding surface 211 of the stationary sealing ring 210. The dynamic pressure generating grooves 19 extend towards the outer diameter side while bending from the inner diameter side end of the stationary sealing ring 210 along the rotation direction of the rotating sealing ring 20. In addition, each dynamic pressure generating groove 19 is arranged at a predetermined interval throughout the entire circumferential range of the sliding surface 211.

[0094] Reference Figure 7 In (a), the fluid flowing into the dynamic pressure generating groove 19 by the rotation of the rotary sealing ring 20 is concentrated at the acute-angled corner 19a located on the outer diameter side of the dynamic pressure generating groove 19 and the rotation direction side of the rotary sealing ring 20, so that the dynamic pressure generating groove 19 can generate dynamic pressure.

[0095] Therefore, during low-speed rotation at startup of the rotating machinery, as in Embodiment 1 above, the static pressure of the sealed fluid F supplied through the through-hole 17 to the sliding surfaces 211, 21 functions autonomously as a force that separates the sliding surfaces 11, 21. On the other hand, during high-speed rotation in normal operation, the dynamic pressure generated by the dynamic pressure generating groove 19 functions autonomously as a force that slightly separates the sliding surfaces 11, 21. In this way, the drive torque can be reduced from startup to normal operation.

[0096] Example 4

[0097] Next, refer to Figures 8-10 Example 4 of the sliding component will be described. Furthermore, descriptions of structures identical to those in Examples 1-3 described above will be omitted.

[0098] like Figure 8 As shown, openings 17a and 217a of through holes 17 and 217 are alternately arranged on the sliding surface 311 of the stationary sealing ring 310 (refer to...). Figure 9 , Figure 10 Openings 17a and 217a are configured on the radial outer diameter side of the sliding surface 311 throughout the entire circumferential range.

[0099] Reference Figure 9 , Figure 10 The openings 217c of the through hole 217 communicating with the storage space 16 and the openings 17c of the through hole 17 communicating with the storage space 16 are alternately arranged and formed on the same circle. The through hole 217 extends in a straight line from the opening 217c toward the sliding surface 311 at an angle toward the outer diameter side. In addition, the through hole 217 is connected to the opening 217a of the sliding surface 311.

[0100] Therefore, the opening 217a of the through hole 217 can be positioned on the outer diameter side, i.e., the side of the sealed fluid F, compared to the storage space 16. Thus, the separation distance towards the atmosphere A is longer compared to Embodiment 1 described above. This not only prevents leakage of the sealed fluid F but also expands the area available for the sealed fluid F radially.

[0101] Furthermore, the through hole 217 is inclined, and its axial dimension is longer than that of the through hole 17, resulting in a greater pressure loss. Additionally, it provides less static pressure to the sliding surface 311, thus reducing leakage to the sealed fluid F.

[0102] Furthermore, the opening 217a of the through hole 217 is formed flush with the sliding surface 311. Therefore, no dynamic pressure is generated during normal operation when the rotation becomes high speed, and it is easy to maintain the initial pressure between the sliding surfaces 311 and 21.

[0103] 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. Even if there are changes or additions that do not depart from the spirit of the present invention, they are also included in the present invention.

[0104] For example, in the above embodiments, the structure of the sliding component applied to the mechanical seal has been described, but it is not limited thereto and can also be applied to components other than mechanical seals such as sliding bearings.

[0105] In addition, the case of an internal mechanical seal is explained, but it is not limited to this and can also be an external mechanical seal.

[0106] In addition, the case where the sealed fluid is a high-pressure liquid is described, but it is not limited to this. It can also be a mist mixed with liquid and gas, a gas, or a low-pressure fluid.

[0107] In addition, the case where the fluid on the leaking side is atmospheric is explained, but it is not limited to this. It can also be a liquid, a mist mixed with liquid and gas, or a fluid with a higher pressure than the fluid being sealed.

[0108] In addition, the structure of a stationary sealing ring with a sliding component having a storage space and a through hole has been described, but it is not limited to this and can also be a rotating sealing ring.

[0109] Furthermore, the structure in which the storage space is divided by the walls located on all four sides has been described, but it is not limited to this; other structures may also be as follows: Figure 11As shown in the static sealing ring 410, the back side between the outer diameter sidewall portion 13 and the inner diameter sidewall portion 15 is open, and the storage space 216 divided by each wall portion 12, 13, 15 is directly connected to the back side of the static sealing ring 310. In this structure, it is preferable to use a shell, outer casing, etc. to narrow the flow path communicating with the back side of the storage space 216, so that the influence of external fluids is less likely to affect the fluid in the storage space 216.

[0110] In addition, the structure in which the storage space is divided by the wall sections arranged in a rectangular frame shape when viewed in section has been described, but it is not limited to this. It can also be a multi-frame shape other than a rectangular frame, or a D-shaped shape when viewed in section with the front side wall section connected to the C-shaped wall section. As long as the wall section is arranged in a cylindrical shape, the cross-sectional shape can be changed appropriately.

[0111] In addition, the structure of the storage space is described as a rectangular shape when viewed in section, but it is not limited to this. It can also be other polygonal shapes or circular shapes, and can be changed appropriately.

[0112] Furthermore, while a continuous circumferential structure of the storage space has been described, it is not limited to this. Multiple storage spaces can also be formed by circumferential segmentation. In this case, it is preferable to form connecting holes on the segmented walls that connect adjacent storage spaces. Additionally, the circumferential flow path cross-sectional area can also vary.

[0113] Alternatively, the stationary sealing ring can also be formed from multiple components. For example, it can also be like... Figure 12 As shown in the static sealing ring 510, it is formed by fixing a separate cover member 114 to a substrate having walls 12, 13, 15.

[0114] In addition, the structure in which the through hole extends in a straight line has been described, but it is not limited to this. As long as it is connected to the sliding surface and the storage space respectively, it can also be in a curved shape, or it can be curved in at least one place. It can be modified appropriately.

[0115] In addition, the structure in which the through holes are arranged in an alternating pattern has been described, but it is not limited to this. It can also be arranged in only one row, or in parallel in the same diameter direction, and can be changed appropriately.

[0116] Furthermore, the structure in which the through holes are arranged at specified intervals has been described, but it is not limited to this. The arrangement may not be at specified intervals, but may be regular or irregular.

[0117] In addition, the structure of the through hole being circular in cross-section is described, but it is not limited to this. It can also be polygonal or star-shaped, and its shape can be changed appropriately.

[0118] In addition, a structure with approximately the same flow path cross-sectional area for through holes was described, but it is not limited to this and can be varied.

[0119] In addition, the case where the fluid is the sealed fluid has been described, but it is not limited to this. It can also be a fluid other than the sealed fluid provided by the pressure inlet.

[0120] In addition, the case where the dynamic pressure generating groove is spiral-shaped has been explained, but it is not limited to this. For example, it can also be a Rayleigh step groove as a positive dynamic pressure generating groove, a reverse Rayleigh groove as a negative dynamic pressure generating groove, a herringbone groove, a rectangular groove, a depression, etc., or a combination of them. It can be changed appropriately.

[0121] Label Explanation

[0122] 10, 10A: Stationary sealing ring (sliding component); 11: Sliding surface; 16: Storage space (cavity); 17: Through hole; 17a: Opening (opening on the sliding surface side); 18: Pressure inlet; 19: Dynamic pressure generating groove; 20: Rotary sealing ring (other sliding components); 21: Sliding surface; 110~510: Stationary sealing ring (sliding component); 111~311: Sliding surface; 118: Pressure inlet; 171~174: Through hole; 216: Storage space; 217: Through hole; A: Atmosphere; F: Sealed fluid (fluid); M: Mechanical seal.

Claims

1. A sliding component disposed at a relatively rotating part of a rotating machine, sliding relative to other sliding components, wherein, The sliding component is provided with: A storage space is formed on the back side of the sliding surface of the sliding component; as well as Multiple through holes, which communicate with the storage space and the sliding surface. The storage space is connected to a connecting path that is separate from the through hole. The connecting passage is connected to the space on the sealed fluid side, which is the outer diameter side or the inner diameter side of the sliding component. The plurality of through holes includes through holes that open at different radial positions on the sliding surface, and through holes that open on the sliding surface at a position closer to the sealed fluid than the radial center.

2. The sliding component according to claim 1, wherein, The storage space is continuous and annular in the circumferential direction of the sliding component.

3. The sliding component according to claim 1 or 2, wherein, The storage space is a continuous cavity in the circumferential direction of the radial cross-section of the sliding component.

4. The sliding component according to claim 1 or 2, wherein, The through hole extends in a straight line.

5. The sliding component according to claim 1 or 2, wherein, The through hole extends perpendicularly to the sliding surface.

6. The sliding component according to claim 1 or 2, wherein, The opening on the sliding surface side of the through hole is flush with the sliding surface.

7. The sliding member according to claim 1 or 2, wherein, A dynamic pressure generating groove is provided on the sliding surface.

8. The sliding component according to claim 1 or 2, wherein, The sliding component is the sliding component on the stationary side.

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