Sliding parts

Abstract

Provided are sliding components that enable sliding surfaces to smoothly slide on each other whether the relative rotation direction is the forward rotation direction or the reverse rotation direction.　Sliding components (10), (20) comprise a pair of sliding surfaces (11), (21) arranged so as to face each other at a position where relative rotation occurs during the driving of a rotary machine. The sliding surface (11) on one side is provided with: first dynamic pressure generation grooves (13) communicating with a space on one side which is of an inner-diameter-side space (S1) and an outer-diameter-side space (S2) and extending in one circumferential direction; second dynamic pressure generation grooves (16) extending in the other circumferential direction; and a conducting groove (17) communicating with the space (S1) on the one side. The conducting groove (17) has an annular groove (19) and communicating grooves (18) that cause the annular groove (19) to communicate with the space (S1) on the one side. The second dynamic pressure generation grooves (16) are arranged on the side of the space (S1) on the one side with respect to the annular groove (19) and communicate with the annular groove (19).

Description

[Technical Field]

[0001] The present invention relates to a sliding part used in a shaft seal or a bearing. [Background technology]

[0002] In rotary machines, a mechanical seal consisting of a pair of annular sliding rings that rotate relative to each other and whose sliding surfaces slide against each other is known as a sliding component for preventing leakage of a sealed fluid around a rotating shaft. In recent years, there has been a demand for reducing the energy lost due to sliding, for example, in order to protect the environment, and some mechanical seals have dynamic pressure generating grooves on the sliding surfaces of the sliding rings.

[0003] For example, the mechanical seal shown in Patent Document 1 has a plurality of dynamic pressure generating grooves formed in the circumferential direction on the sliding surface of one sliding ring, which grooves communicate with a space on the sealed fluid side, which is on the outer diameter side of the sliding surface, and which extend in the inner diameter direction while inclining to one side in the circumferential direction.

[0004] When the sliding rings rotate relative to one another, the sealed fluid concentrates from the space on the sealed fluid side toward the closed end of the dynamic pressure generating groove, generating positive pressure that separates the sliding surfaces, and a fluid film of the sealed fluid is formed between the sliding surfaces, improving lubrication and allowing the sliding surfaces to slide smoothly against each other. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2020 / 162025 (Page 14, Figure 10) Summary of the Invention [Problem to be solved by the invention]

[0006] Some types of rotary machines to which mechanical seals such as those disclosed in Patent Document 1 are applied switch the rotation direction of the sliding ring depending on the situation, and therefore a mechanical seal that can accommodate both relative rotation directions of the sliding ring has been desired. However, while the mechanical seal of Patent Document 1 is able to improve lubrication by using the positive pressure generated by the dynamic pressure generating grooves during relative rotation of the sliding ring, it does not take into consideration the relative rotation of the sliding ring in the reverse direction, and therefore is unable to generate positive pressure in the dynamic pressure generating grooves during relative rotation of the sliding ring in the reverse direction, making it impossible to improve lubrication between the sliding surfaces.

[0007] The present invention has been made in light of these problems, and aims to provide a sliding component that allows sliding surfaces to slide smoothly against each other regardless of the relative rotation direction, whether forward or reverse. [Means for solving the problem]

[0008] In order to solve the above problems, the sliding component of the present invention comprises: A sliding component having a pair of sliding surfaces arranged opposite to each other at positions that rotate relative to each other when a rotary machine is driven, one sliding surface is provided with a first dynamic pressure generating groove extending in one circumferential direction and communicating with one space of the inner diameter side space and the outer diameter side space, a second dynamic pressure generating groove extending in the other circumferential direction, and a conducting groove communicating with the one space, The second dynamic pressure generating groove is disposed in a space on one side of the conducting groove and communicates with the conducting groove. According to this, during relative rotation in one circumferential direction while the rotary machine is in operation, the fluid in the space on one side is supplied between the sliding surfaces from the closed end of the first hydrodynamic groove. Furthermore, during relative rotation in the other circumferential direction while the rotary machine is in operation, the fluid in the space on one side is supplied between the sliding surfaces from the closed end of the second hydrodynamic groove through the conducting groove. Therefore, good lubrication is achieved between the sliding surfaces in either direction of relative rotation.

[0009] A land extending in the circumferential direction may be provided between the first dynamic pressure generating groove and the second dynamic pressure generating groove. According to this, the positive pressures generated by the first dynamic pressure generating groove and the second dynamic pressure generating groove are generated in the same land, so the separation state between the sliding surfaces is substantially the same regardless of the relative rotation direction.

[0010] The closed end of the first dynamic pressure generating groove and the closed end of the second dynamic pressure generating groove may face each other in the radial direction. With this, the fluid supplied between the sliding surfaces from one of the dynamic pressure generating grooves is efficiently collected by the other dynamic pressure generating groove disposed opposite to it.

[0011] The conductive groove may have an annular groove and a communication groove that communicates the annular groove with the space on the one side. This allows the annular groove to reliably collect the fluid flowing between the sliding surfaces from the space on one side to the space on the other side. Also, since the annular groove can store a large amount of fluid, the fluid is reliably supplied to the second hydrodynamic groove.

[0012] The first dynamic pressure generating groove and the second dynamic pressure generating groove may be spiral grooves. This allows the first dynamic pressure generating grooves and the second dynamic pressure generating grooves to be densely arranged in the circumferential direction.

[0013] The communication groove may extend so as not to intersect with the first dynamic pressure generating groove and the second dynamic pressure generating groove. This prevents the communication groove from interfering with the generation of dynamic pressure in the first dynamic pressure generating groove and the second dynamic pressure generating groove.

[0014] A third dynamic pressure generating groove may be provided on the pair of sliding surfaces on the space side opposite the conductive groove. According to this, since the third dynamic pressure generating groove is provided in the space on the other side of the conductive groove, the lubrication and sealing properties between the sliding surfaces are further improved by the dynamic pressure generated in the third dynamic pressure generating groove.

[0015] The third dynamic pressure generating groove may be a bent groove that communicates with the conductive groove. According to this, the state of dynamic pressure in the third dynamic pressure generating groove changes depending on the relative rotation direction of the sliding surface. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a vertical cross-sectional view showing an example of a mechanical seal according to a first embodiment of the present invention; [Figure 2] 3 is a view of the sliding surface of the stationary seal ring in the first embodiment as viewed from the axial direction. FIG. [Figure 3] 4 is an enlarged view of the sliding surface of the stationary seal ring when the rotary seal ring rotates forward in the first embodiment, as viewed from the axial direction. FIG. [Figure 4] 4 is an enlarged view of the sliding surface of the stationary seal ring when the rotary seal ring rotates in reverse in the first embodiment, as viewed from the axial direction. FIG. [Figure 5] FIG. 10 is a view of the sliding surface of the stationary seal ring according to the second embodiment of the present invention, as viewed from the axial direction. [Figure 6] FIG. 10 is a view of the sliding surface of a stationary seal ring according to a third embodiment of the present invention, as viewed from the axial direction. [Figure 7] 11 is an enlarged view of the sliding surface of the stationary seal ring when the rotary seal ring rotates forward in the third embodiment, as viewed from the axial direction. FIG. [Figure 8] FIG. 11 is an enlarged view of the sliding surface of the stationary seal ring when the rotary seal ring rotates in reverse in the third embodiment, as viewed from the axial direction. [Figure 9] FIG. 10 is a view of the sliding surface of a stationary seal ring according to a fourth embodiment of the present invention, as viewed from the axial direction. [Figure 10] FIG. 10 is a view of the sliding surface of the stationary seal ring according to the fifth embodiment of the present invention, as viewed from the axial direction. [Figure 11] 13 is an enlarged view of the sliding surface of the stationary seal ring when the rotary seal ring rotates forward in the fifth embodiment, as viewed from the axial direction. FIG. [Figure 12] FIG. 11 is an enlarged view of the sliding surface of the stationary seal ring when the rotary seal ring rotates in reverse in the fifth embodiment, as viewed from the axial direction. [Figure 13] FIG. 13 is an enlarged view of the sliding surface of the stationary seal ring according to the sixth embodiment of the present invention, as viewed from the axial direction. [Figure 14] FIG. 13 is an enlarged view of the sliding surface of the stationary seal ring according to the seventh embodiment of the present invention, as viewed from the axial direction. [Figure 15] 10 is an enlarged view of the sliding surface of the stationary seal ring of Modification 1 of the first embodiment, as viewed from the axial direction. FIG. [Figure 16] 10 is an enlarged view of the sliding surface of the stationary seal ring of the second modified example of the first embodiment, viewed from the axial direction. FIG. [Figure 17] 10 is an enlarged view of the sliding surface of the stationary seal ring of the third modified example of the first embodiment, as viewed from the axial direction. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sliding element according to an embodiment of the present invention will be described below with reference to the accompanying drawings. [Example]

[0018] A mechanical seal as a sliding component according to a first embodiment will be described with reference to Figures 1 to 4. In this embodiment, the atmosphere A is present in the inner space S1 of the mechanical seal, and the sealed fluid F is present in the outer space S2. The inner diameter side of the sliding ring constituting the mechanical seal will be described as the leakage side (low pressure side) as the other space, and the outer diameter side as the sealed fluid side (high pressure side) as one space. For ease of explanation, grooves formed on the sliding surface may be marked with dots in the drawings.

[0019] The automotive mechanical seal shown in Fig. 1 is an inside type that seals a sealed fluid F in an outer space S2 that tends to leak from the outer diameter side toward the inner diameter side of the sliding surface, and the inner space S1 is in communication with the atmosphere A. In this embodiment, the sealed fluid F is a high-pressure liquid, and the atmosphere A is a gas with a lower pressure than the sealed fluid F.

[0020] The mechanical seal is mainly composed of a rotary seal ring 20 as the other sliding ring and a static seal ring 10 as one sliding ring. The rotary seal ring 20 is annular and is mounted on a rotary shaft 1 via a sleeve 2 so that it can rotate together with the rotary shaft 1. The stationary seal ring 10 is annular and is mounted on a seal cover 5 fixed to a housing 4 of the device to which it is attached so that it can move axially but not rotate. The stationary seal ring 10 is axially biased by an elastic member 7. The sliding surface 11 of the stationary seal ring 10 and the sliding surface 21 of the rotary seal ring 20 slide closely against each other. The sliding surface 21 of the rotary seal ring 20 is flat and does not have any recesses such as grooves.

[0021] The stationary seal ring 10 and the rotating seal ring 20 are typically formed from a combination of SiC (hard material) or SiC (hard material) and carbon (soft material), but any sliding material used for mechanical seals can be used. Examples of SiC include sintered bodies using boron, aluminum, carbon, or other sintering aids, as well as materials consisting of two or more phases with different components and compositions, such as SiC with dispersed graphite particles, reaction-sintered SiC consisting of SiC and Si, SiC-TiC, and SiC-TiN. Examples of carbon include a mixture of carbonaceous and graphite materials, resin-molded carbon, and sintered carbon. In addition to the above sliding materials, metal materials, resin materials, surface-modified materials (coating materials), and composite materials are also applicable.

[0022] 2 to 4, the rotary seal ring 20 slides relative to the stationary seal ring 10 in a clockwise direction as indicated by the solid arrow, or in a counterclockwise direction as indicated by the dashed arrow. In the following description, the direction of the solid arrow indicates the forward rotation direction of the rotary seal ring 20, and the direction of the dashed arrow indicates the reverse rotation direction of the rotary seal ring 20.

[0023] The sliding surface 11 of the stationary seal ring 10 is provided with a plurality of first dynamic pressure generating grooves 13, a plurality of second dynamic pressure generating grooves 16, and one conducting groove 17. The conducting groove 17 is made up of a plurality of communicating grooves 18 and an annular groove 19.

[0024] A plurality of first dynamic pressure generating grooves 13 (33 in this embodiment) are arranged circumferentially on the outer diameter side of the sliding surface 11. An outer diameter side end 13A of each first dynamic pressure generating groove 13 communicates with the external space S2, and extends in the forward rotation direction of the rotary seal ring 20, i.e., in one circumferential direction, based on this communication point. More specifically, the first dynamic pressure generating groove 13 is a spiral groove that extends in an arc shape while inclining with a clockwise component from the outer diameter side toward the inner diameter side. Furthermore, an inner diameter side end 13B of each first dynamic pressure generating groove 13 has a closed shape, i.e., a closed end.

[0025] The first dynamic pressure generating grooves 13 have a constant depth in the extension direction.

[0026] A plurality of second dynamic pressure generating grooves 16 (33 in this embodiment) are arranged in the circumferential direction on the outer diameter side of the annular groove 19. An inner diameter side end 16A of each second dynamic pressure generating groove 16 communicates with the annular groove 19, and extends in the reverse rotation direction of the rotary seal ring 20, i.e., the other circumferential direction, from this communicating point. More specifically, the second dynamic pressure generating groove 16 is a spiral groove that extends in an arc shape while inclining with a counterclockwise component from the inner diameter side toward the outer diameter side. Furthermore, an outer diameter side end 16B of each second dynamic pressure generating groove 16 has a closed shape, i.e., a closed end.

[0027] The second dynamic pressure generating grooves 16 have a constant depth in the extension direction. In this embodiment, the depth of the second dynamic pressure generating grooves 16 is the same as the depth of the first dynamic pressure generating grooves 13.

[0028] An inner diameter side end 13B of the first dynamic pressure generating groove 13 and an outer diameter side end 16B of the second dynamic pressure generating groove 16 are disposed opposite each other in the radial direction with a land 12A (described later) interposed therebetween.

[0029] A plurality of communicating grooves 18 (three in this embodiment) are arranged evenly in the circumferential direction on the outer diameter side of the sliding surface 11. The communicating grooves 18 communicate with the external space S2 and extend in an arc shape while inclining with a clockwise component from the outer diameter side toward the inner diameter side.

[0030] More specifically, when viewed in the axial direction, the communicating grooves 18 extend substantially parallel to the first dynamic pressure generating grooves 13 and the second dynamic pressure generating grooves 16. In other words, the communicating grooves 18 extend so as not to intersect with the first dynamic pressure generating grooves 13 and the second dynamic pressure generating grooves 16.

[0031] Furthermore, the communicating grooves 18 are formed to be longer in the extension direction than the first dynamic pressure generating grooves 13. A predetermined number of first dynamic pressure generating grooves 13 and second dynamic pressure generating grooves 16 (11 each in this embodiment) are arranged between adjacent communicating grooves 18 in the circumferential direction.

[0032] The communicating grooves 18 have a constant depth in the extension direction. The depth of the communicating grooves 18 is greater than the depths of the first dynamic pressure generating grooves 13 and the second dynamic pressure generating grooves 16.

[0033] The annular groove 19 is formed in a circular ring shape when viewed in the axial direction, and the inner diameter side end of each communicating groove 18 is communicated with the annular groove 19. In other words, the annular groove 19 is communicated with the outer space S2 by each communicating groove 18.

[0034] The annular groove 19 has a constant depth in the circumferential direction. In this embodiment, the depth of the annular groove 19 is the same as the depth of the communication groove 18.

[0035] Furthermore, the portion of the sliding surface 11 other than the first dynamic pressure generating groove 13, the second dynamic pressure generating groove 16, the communicating groove 18, and the annular groove 19 is a land 12 having a flat surface arranged on the same plane. The flat surface of the land 12 functions as a sliding surface that essentially slides against the sliding surface 21 of the rotating seal ring 20.

[0036] In detail, the land 12 includes a land between circumferentially adjacent first hydrodynamic pressure generating grooves 13, a land between circumferentially adjacent first hydrodynamic pressure generating grooves 13 and connecting grooves 18, a land between circumferentially adjacent second hydrodynamic pressure generating grooves 16, a land between circumferentially adjacent second hydrodynamic pressure generating grooves 16 and connecting grooves 18, a land 12A extending in the circumferential direction and disposed between the first hydrodynamic pressure generating groove 13 and the second hydrodynamic pressure generating groove 16 spaced apart in the radial direction, and an annular land located on the inner diameter side of the annular groove 19, and these lands are arranged on the same plane to form the flat surface of the land 12.

[0037] Next, the operation of the stationary seal ring 10 and the rotating seal ring 20 during relative rotation in the forward direction will be described with reference to FIG.

[0038] First, when the rotary seal ring 20 is not rotating and is at a standstill, the sealed fluid F flows into the first dynamic pressure generating groove 13 from the opening at the end 13A, and also flows from the opening on the outer diameter side of the communicating groove 18 into the second dynamic pressure generating groove 16 through said communicating groove 18 and the annular groove 19. Furthermore, since the static seal ring 10 is urged toward the rotary seal ring 20 by the elastic member 7, the sliding surfaces 11, 21 are in contact with each other, and almost no sealed fluid F leaks out between the sliding surfaces 11, 21 into the internal space S1.

[0039] As shown in FIG. 3, when the rotating seal ring 20 rotates relative to the stationary seal ring 10 in the forward direction, the sealed fluid F in the first dynamic pressure generating grooves 13 and the second dynamic pressure generating grooves 16 moves in the forward rotation direction of the rotating seal ring 20 due to shear with the sliding surface 21.

[0040] Specifically, in the first hydrodynamic groove 13, the sealed fluid F moves from the opening at the outer diameter side end 13A toward the inner diameter side end 13B as shown by the arrow F1. This increases the pressure at the end 13B and its vicinity. That is, a positive pressure is generated at the end 13B of the first hydrodynamic groove 13 and the land 12A in its vicinity.

[0041] Furthermore, the force of the positive pressure generated at the end 13B of the first hydrodynamic pressure generating groove 13 and the land 12A in the vicinity thereof causes a slight separation between the sliding surfaces 11 and 21 (not shown). In detail, the absolute value of the positive pressure generated by the first hydrodynamic pressure generating groove 13 is 16 is greater than the absolute value of the negative pressure generated.

[0042] As a result, as shown by arrow F2, the sealed fluid F in the first hydrodynamic grooves 13 flows mainly between the sliding surfaces 11, 21. The presence of the sealed fluid F between the sliding surfaces 11, 21 improves lubrication even during low-speed rotation, and can suppress wear between the sliding surfaces 11, 21. Furthermore, because the floating distance between the sliding surfaces 11, 21 is short, only a small amount of the sealed fluid F leaks into the external space S2.

[0043] At this time, since the sliding surfaces 11 and 21 are slightly spaced apart, the sealed fluid F in the communication groove 18 and the annular groove 19 also flows into the gap between the sliding surfaces 11 and 21. Therefore, the sealed fluid F flows efficiently between the sliding surfaces 11 and 21.

[0044] Meanwhile, in the second dynamic pressure generating groove 16, the sealed fluid F moves from the outer diameter side end 16B toward the inner diameter side end 16A as shown by arrow F3. As a result, the fluid pressure in the vicinity of end 16B becomes relatively lower than the surrounding fluid pressure. In other words, a relative negative pressure is generated in the vicinity of end 16B, and the sealed fluid F between the sliding surfaces 11, 21 is sucked into the second dynamic pressure generating groove 16 as shown by arrow F4.

[0045] The sealed fluid F sucked into the second dynamic pressure generating grooves 16 is recovered into the annular groove 19. The annular groove 19 communicates with the outer space S2 through the communicating grooves 18, allowing the sealed fluid F to be taken in and out. Therefore, when more sealed fluid F is recovered than can be stored in the annular groove 19, the excess sealed fluid F is returned to the outer space S2.

[0046] Next, the operation of the stationary seal ring 10 and the rotary seal ring 20 when they rotate relative to each other in the opposite directions will be described with reference to FIG.

[0047] As shown in FIG. 4, when the rotating seal ring 20 rotates in the reverse direction relative to the stationary seal ring 10, the sealed fluid F in the first dynamic pressure generating grooves 13 and the second dynamic pressure generating grooves 16 moves in the reverse rotation direction of the rotating seal ring 20 due to shear with the sliding surface 21.

[0048] Specifically, in the first hydrodynamic pressure generating groove 13, the sealed fluid F moves from the inner diameter side end 13B toward the opening of the outer diameter side end 13A as shown by the arrow F1'. As a result, the fluid pressure in the vicinity of the end 13B becomes relatively lower than the surrounding fluid pressure. In other words, a relative negative pressure is generated in the vicinity of the end 13B, and the sealed fluid F between the sliding surfaces 11 and 21 is sucked into the first hydrodynamic pressure generating groove 13 as shown by the arrow F2'.

[0049] The sealed fluid F sucked into the first dynamic pressure generating groove 13 is returned to the outer space S2 from the opening at the outer diameter side end 13A.

[0050] Meanwhile, within the second dynamic pressure generating groove 16, the sealed fluid F moves from the inner diameter side end 16A toward the outer diameter side end 16B as shown by the arrow F3'. This increases the pressure at the end 16B and its vicinity. That is, a positive pressure is generated at the end 16B of the second dynamic pressure generating groove 16 and the land 12A in its vicinity.

[0051] Furthermore, the force of the positive pressure generated at the end 16B of the second dynamic pressure generating groove 16 and the land 12A in the vicinity thereof causes a slight separation between the sliding surfaces 11 and 21 (not shown). 16 The absolute value of the positive pressure generated by the second hydrodynamic pressure generating groove 16 is greater than the absolute value of the negative pressure generated by the first hydrodynamic pressure generating groove 13. As a result, the sealed fluid F in the second hydrodynamic pressure generating groove 16 mainly flows between the sliding surfaces 11 and 21 as shown by arrow F4'.

[0052] As explained above, when the rotating seal ring 20 rotates relative to the stationary seal ring 10 in the forward direction, the sealed fluid F in the outer space S2 is supplied from the end 13B of the first dynamic pressure generating groove 13 to between the sliding surfaces 11, 21. When the rotating seal ring 20 rotates relative to the stationary seal ring 10 in the reverse direction, the sealed fluid F in the outer space S2 is supplied from the end 16B of the second dynamic pressure generating groove 16 through the communicating groove 18 and the annular groove 19 to between the sliding surfaces 11, 21. Therefore, good lubrication is achieved between the sliding surfaces 11, 21 in either direction of relative rotation.

[0053] Furthermore, when the rotating seal ring 20 rotates relative to the stationary seal ring 10 in the forward direction, a relative negative pressure is generated near the end 16B of the second dynamic pressure generating groove 16, and the sealed fluid F is sucked between the sliding surfaces 11, 21. Furthermore, when the rotating seal ring 20 rotates relative to the stationary seal ring 10 in the reverse direction, a relative negative pressure is generated near the end 13B of the first dynamic pressure generating groove 13, and the sealed fluid F is sucked between the sliding surfaces 11, 21. Therefore, leakage of the sealed fluid F into the internal space S1 is suppressed.

[0054] Furthermore, a land 12A extending in the circumferential direction is provided between the first dynamic pressure generating groove 13 and the second dynamic pressure generating groove 16. With this, the positive pressure generated at the end 13B of the first dynamic pressure generating groove 13 and the end 16B of the second dynamic pressure generating groove 16 is generated at the same land 12A, so the separation state between the sliding surfaces 11, 21 is approximately the same regardless of the relative rotation direction.

[0055] Furthermore, the end 13B of the first hydrodynamic pressure generating groove 13 and the end 16B of the second hydrodynamic pressure generating groove 16 are opposed to each other in the radial direction with the land 12A sandwiched therebetween. With this, when the rotating seal ring 20 rotates relative to the stationary seal ring 10 in the forward direction, the sealed fluid F supplied from the end 13B of the first hydrodynamic pressure generating groove 13 to between the sliding surfaces 11, 21 is efficiently recovered by the oppositely disposed end 16B of the second hydrodynamic pressure generating groove 16. When the rotating seal ring 20 rotates relative to the stationary seal ring 10 in the reverse direction, the sealed fluid F supplied from the end 16B of the second hydrodynamic pressure generating groove 16 to between the sliding surfaces 11, 21 is efficiently recovered by the oppositely disposed end 13B of the first hydrodynamic pressure generating groove 13. This prevents the positive pressure from becoming too high, regardless of the relative rotation speed.

[0056] The conducting groove 17 is composed of an annular groove 19 and a communicating groove 18 that communicates the annular groove 19 with the outer space S2. As the annular groove 19 is disposed closer to the inner space S1 than the first dynamic pressure generating groove 13 and the second dynamic pressure generating groove 16, the sealed fluid F flowing between the sliding surfaces 11, 21 from the outer space S2 toward the inner space S1 can be reliably collected. Furthermore, the annular groove 19 can store a large amount of sealed fluid F, so that the sealed fluid F is reliably supplied to the second dynamic pressure generating groove 16.

[0057] A plurality of communication grooves 18 are provided in the circumferential direction of the annular groove 19. This allows the sealed fluid F to be efficiently introduced or discharged through the plurality of communication grooves 18.

[0058] Furthermore, since a large amount of the sealed fluid F is present in the deep communicating groove 18, the sealed fluid F is easily supplied between the sliding surfaces 11 and 21 which are slightly spaced apart due to the relative rotation.

[0059] Furthermore, the first dynamic pressure generating grooves 13 and the second dynamic pressure generating grooves 16 are spiral grooves that extend radially while inclining circumferentially. This allows the first dynamic pressure generating grooves 13 and the second dynamic pressure generating grooves 16 to be densely arranged in the circumferential direction. In other words, the stationary seal ring 10 has a high degree of freedom in design.

[0060] Furthermore, the communicating grooves 18 extend so as not to intersect with the first dynamic pressure generating groove 13 and the second dynamic pressure generating groove 16. For example, the communicating grooves 18 are not disposed so as to cross the land 12A between the end 13B of the first dynamic pressure generating groove 13 and the end 16B of the second dynamic pressure generating groove 16, so they do not interfere with the generation of dynamic pressure by the first dynamic pressure generating groove 13 and the second dynamic pressure generating groove 16.

[0061] Furthermore, since the communication grooves 18 extend parallel to the first dynamic pressure generating grooves 13 and the second dynamic pressure generating grooves 16, the first dynamic pressure generating grooves 13 and the second dynamic pressure generating grooves 16 can be arranged even more densely in the circumferential direction. [Example]

[0062] Next, a mechanical seal as a sliding component according to a second embodiment will be described with reference to Fig. 5. Note that a description of the same configuration as in the first embodiment will be omitted.

[0063] The stationary seal ring 210 in the mechanical seal of the second embodiment differs from the stationary seal ring 10 of the first embodiment in the configuration of the conducting groove, but other configurations are the same as the stationary seal ring 10 of the first embodiment.

[0064] 5, the conducting groove 217 of the stationary seal ring 210 is composed of a communicating groove 218 and an arc groove 219. The arc groove 219 extends circumferentially in a clockwise direction from the inner diameter side end of the communicating groove 218 concentrically with the stationary seal ring 210. A plurality of the conducting grooves 217 (three in this embodiment) are provided in the circumferential direction.

[0065] The inner diameter side end 16 A of each second dynamic pressure generating groove 16 communicates with the arc groove 219 . [Example]

[0066] Next, a mechanical seal as a sliding component according to a third embodiment will be described with reference to Figures 6 to 8. Note that a description of the same configuration as in the first embodiment will be omitted.

[0067] The stationary seal ring 310 in the mechanical seal of this third embodiment differs from the stationary seal ring 10 of the first embodiment in the configuration of the first and second dynamic pressure generating grooves, but otherwise has the same configuration as the stationary seal ring 10 of the first embodiment.

[0068] As shown in FIG. 6, the sliding surface 311 of the stationary seal ring 310 is provided with a plurality of first dynamic pressure generating mechanisms 313, a plurality of communicating grooves 18, an annular groove 19, and a plurality of second dynamic pressure generating mechanisms 316.

[0069] The first dynamic pressure generating mechanism 313 is made up of a first deep groove 313A and a first Rayleigh step 313B as a first dynamic pressure generating groove.

[0070] The first deep groove 313A has an outer diameter side end communicating with the outer space S2 and extends in the inner diameter direction. The first deep groove 313A is formed slightly shallower than the communicating groove 18 and the annular groove 19.

[0071] The first Rayleigh step 313B extends clockwise from the inner diameter side of the first deep groove 313A in the circumferential direction concentric with the stationary seal ring 310. The first Rayleigh step 313B is formed shallower than the first deep groove 313A.

[0072] The second dynamic pressure generating mechanism 316 is composed of a second deep groove 316A and a second Rayleigh step 316B as a second dynamic pressure generating groove.

[0073] The second deep groove 316A extends in the outer diameter direction, with its inner diameter side end communicating with the annular groove 19. The second deep groove 316A is formed slightly shallower than the communicating groove 18 and the annular groove 19. The second deep groove 316A is formed to the same depth as the first deep groove 313A.

[0074] The second Rayleigh step 316B extends counterclockwise from the outer diameter side of the second deep groove 316A in the circumferential direction concentric with the stationary seal ring 310. The second Rayleigh step 316B is formed shallower than the second deep groove 316A. The second Rayleigh step 316B is formed to the same depth as the first Rayleigh step 313B.

[0075] In this third embodiment, the first deep groove 313A and the second deep groove 316A are formed slightly shallower than the communicating groove 18 and the annular groove 19, but they may be formed to the same depth. Also, the first deep groove 313A and the second deep groove 316A may be formed to the same depth as the first Rayleigh step 313B and the second Rayleigh step 316B.

[0076] Furthermore, in this Example 3, the first deep groove 313A and the second deep groove 316A are formed to the same depth, but they may be formed to different depths. Also, in this Example 3, the first Rayleigh step 313B and the second Rayleigh step 316B are formed to the same depth, but they may be formed to different depths.

[0077] Next, the operation of the stationary seal ring 310 and the rotary seal ring 20 (see FIG. 1) during relative rotation in the forward direction will be described with reference to FIG.

[0078] As shown in FIG. 7, when the rotating seal ring 20 rotates relative to the stationary seal ring 310 in the forward direction, the sealed fluid F in the first dynamic pressure generating mechanism 313 and the second dynamic pressure generating mechanism 316 moves in the forward rotation direction of the rotating seal ring 20 due to shear with the sliding surface 21.

[0079] Specifically, in the first dynamic pressure generating mechanism 313, the sealed fluid F in the first deep groove 313A moves from the communicating portion between the first deep groove 313A and the first Rayleigh step 313B toward the closed end 313a of the first Rayleigh step 313B as shown by arrow F10. This generates a positive pressure at and in the vicinity of the closed end 313a of the first Rayleigh step 313B, causing the sliding surfaces 311 and 21 to separate from each other, and causing the sealed fluid F to flow between the sliding surfaces 311 and 21 as shown by arrow F11.

[0080] At this time, in the second dynamic pressure generating mechanism 316, the sealed fluid F in the second Rayleigh step 316B moves toward the second deep groove 316A as shown by the arrow F12. As a result, a relative negative pressure is generated in the vicinity of the closed end 316a of the second Rayleigh step 316B, and the sealed fluid F between the sliding surfaces 311 and 21 is sucked into the second Rayleigh step 316B as shown by the arrow F13.

[0081] Next, the operation of the stationary seal ring 310 and the rotary seal ring 20 (see FIG. 1) during relative rotation in the opposite direction will be described with reference to FIG.

[0082] As shown in FIG. 8, when the rotating seal ring 20 rotates in the reverse direction relative to the stationary seal ring 310, the sealed fluid F in the first dynamic pressure generating mechanism 313 and the second dynamic pressure generating mechanism 316 moves in the reverse rotation direction of the rotating seal ring 20 due to shear with the sliding surface 21.

[0083] Specifically, in first dynamic pressure generating mechanism 313, sealed fluid F in first Rayleigh step 313B moves toward first deep groove 313A as shown by arrow F10'. This generates a relative negative pressure at and near closed end 313a of first Rayleigh step 313B, and sealed fluid F between sliding surfaces 311 and 21 is sucked into first Rayleigh step 313B as shown by arrow F11'.

[0084] At this time, in the second dynamic pressure generating mechanism 316, the sealed fluid F in the second deep groove 316A moves from the communicating portion between the second deep groove 316A and the second Rayleigh step 316B toward the closed end 316a of the second Rayleigh step 316B as shown by arrow F12'. This generates a positive pressure at and in the vicinity of the closed end 316a of the second Rayleigh step 316B, causing the sliding surfaces 311 and 21 to separate from each other, and causing the sealed fluid F to flow between the sliding surfaces 311 and 21 as shown by arrow F13'.

[0085] In this way, in the stationary seal ring 310 of the third embodiment, it is possible to achieve both lubrication and sealing performance between the sliding surfaces 311 and 21 regardless of the relative rotation direction of the rotary seal ring 20 . [Example]

[0086] Next, a mechanical seal as a sliding component according to a fourth embodiment will be described with reference to Fig. 9. Note that a description of the same configuration as in the first embodiment will be omitted.

[0087] 9, the mechanical seal of the fourth embodiment is an outside type in which the sealed fluid F exists in the inner space S1 and the atmosphere A exists in the outer space S2. In the fourth embodiment, the inner space S1 functions as one side space and the outer space S2 functions as the other side space.

[0088] The stationary seal ring 410 in the mechanical seal of this fourth embodiment is provided with a plurality of first dynamic pressure generating grooves 413, a plurality of communicating grooves 418, an annular groove 419, and a plurality of second dynamic pressure generating grooves 416. The plurality of communicating grooves 418 and the annular groove 419 form one conducting groove 417.

[0089] The first dynamic pressure generating groove 413 has an inner diameter side end 413B that communicates with the internal space S1 and extends in one circumferential direction, i.e., in the forward rotation direction of the rotary seal ring 20, based on this communication point. More specifically, the first dynamic pressure generating groove 413 is a spiral groove that extends in an arc shape while inclining with a clockwise component from the inner diameter side toward the outer diameter side. Furthermore, the outer diameter side end 413 of the first dynamic pressure generating groove 413 has a closed shape, i.e., a closed end.

[0090] The communication groove 418 communicates with the internal space S1 and extends in an arc shape while inclining with a clockwise component from the inner diameter side to the outer diameter side.

[0091] The outer diameter side end of each communication groove 418 communicates with the annular groove 419. In other words, the annular groove 419 communicates with the internal space S1 through each communication groove 418.

[0092] The second dynamic pressure generating groove 416 has an outer diameter side end 416B that communicates with the annular groove 419 and extends in the reverse rotation direction of the rotary seal ring 20, i.e., in the other circumferential direction, based on this communicating point. More specifically, the second dynamic pressure generating groove 416 is a spiral groove that extends in an arc shape while inclining with a counterclockwise component from the outer diameter side toward the inner diameter side. Furthermore, the inner diameter side end 416A of the second dynamic pressure generating groove 416 has a closed shape, i.e., a closed end.

[0093] The grooves may be arranged on the inner diameter side in the second and third embodiments as well, and may be of the outside type. The grooves may also be arranged on the inner diameter side in the fourth, fifth, and sixth embodiments and the first, second, and third modifications of the first embodiment, which will be described later, and may be of the outside type. [Example]

[0094] Next, a mechanical seal as a sliding component according to a fifth embodiment will be described with reference to Figures 10 to 12. Note that a description of the same configuration as in the first embodiment will be omitted.

[0095] The stationary seal ring 510 in the mechanical seal of this embodiment 5 differs from the stationary seal ring 10 of embodiment 1 in that it is provided with a third dynamic pressure generating groove 530, but otherwise has the same configuration as the stationary seal ring 10 of embodiment 1.

[0096] As shown in FIG. 10, a plurality of third dynamic pressure generating grooves 530 (36 in this embodiment) are provided in the circumferential direction on the sliding surface 511 of the stationary seal ring 510 on the inner diameter side of the annular groove 19, i.e., at positions where the first dynamic pressure generating grooves 13 and the second dynamic pressure generating grooves 16 are not provided.

[0097] 11 and 12, the third dynamic pressure generating groove 530 is a bent groove whose outer diameter side end portion communicates with the annular groove 19. More specifically, the third dynamic pressure generating groove 530 has a first inclined groove portion 531 and a second inclined groove portion 532. The third dynamic pressure generating groove 530 has a constant depth in the extension direction. Note that the third dynamic pressure generating groove 530 has the same depth as the first dynamic pressure generating groove 13 and the second dynamic pressure generating groove 16, but may be formed to a different depth.

[0098] The first inclined groove portion 531 extends radially inward while inclining in the reverse rotation direction of the rotary seal ring 20, i.e., in another circumferential direction, based on the point of communication with the annular groove 19. The second inclined groove portion 532 communicates with the end portion on the inner diameter side of the first inclined groove portion 531, and extends radially inward while inclining in the forward rotation direction of the rotary seal ring 20, i.e., in one circumferential direction, based on the point of communication.

[0099] This third dynamic pressure generating groove 530 has a corner portion 530a formed by a side surface 531a located in the reverse rotation direction that defines the first inclined groove portion 531, and a side surface 532a located in the reverse rotation direction that defines the second inclined groove portion 532.

[0100] Moreover, one second inclined groove portion 532 is disposed on the inner diameter side of a corner 530a of the third dynamic pressure generating groove 530 adjacent thereto in the forward rotation direction. Moreover, the second inclined groove portion 532 has a longer length in the extension direction than the first inclined groove portion 531. Moreover, the closed end of the second inclined groove portion 532 is disposed on the forward rotation direction side of the corner 530a of the third dynamic pressure generating groove 530 adjacent thereto in the forward rotation direction.

[0101] Next, the operation of the stationary seal ring 510 and the rotary seal ring 20 during relative rotation in the forward direction will be described with reference to FIG.

[0102] 11, when the rotating seal ring 20 rotates relative to the stationary seal ring 510 in the forward direction, the sealed fluid F moves in the first dynamic pressure generating groove 13 as shown by arrow F1, and the sealed fluid F in the first dynamic pressure generating groove 13 flows mainly between the sliding surfaces 511, 21 as shown by arrow F2. Meanwhile, in the second dynamic pressure generating groove 16, the sealed fluid F moves as shown by arrow F3, and the sealed fluid F between the sliding surfaces 511, 21 is sucked into the second dynamic pressure generating groove 16 as shown by arrow F4.

[0103] At this time, in the first inclined groove portion 531 of the third dynamic pressure generating groove 530, the sealed fluid F moves toward the annular groove 19 as shown by arrow F5, and in the second inclined groove portion 532, the sealed fluid F moves toward the closed end on the inner diameter side as shown by arrow F6.

[0104] As a result, the sealed fluid F in the first inclined groove portion 531 moves toward the annular groove 19, and the sealed fluid F in the second inclined groove portion 532 is discharged between the sliding surfaces 511 and 21. As a result, the third dynamic pressure generating groove 530 becomes relatively negative pressure, and a cavitation region C is formed in the circumferential direction near the third dynamic pressure generating groove 530 (see the shaded portion in FIG. 11). The shaded portion in FIG. 11 indicates the cavitation region C, and is illustrated more exaggerated than it actually is.

[0105] In this way, the cavitation region C is formed on the inner diameter side of the annular groove 19 on the sliding surface 511 of the stationary seal ring 510, and therefore the sealed fluid F is inhibited from moving toward the inner diameter side of the annular groove 19. This makes it possible to inhibit the sealed fluid F from leaking into the internal space S1, and thereby to supplementarily improve the sealing performance between the sliding surfaces 511, 21.

[0106] Furthermore, since the third dynamic pressure generating grooves 530 have components extending in the radial direction, the radial width of the cavitation region C can be ensured to be large, and the sealed fluid F is less likely to leak into the internal space S1.

[0107] Next, the operation of the stationary seal ring 510 and the rotary seal ring 20 when they rotate relative to each other in the opposite directions will be described with reference to FIG.

[0108] 12, when the rotating seal ring 20 rotates in the opposite direction relative to the stationary seal ring 510, the sealed fluid F moves in the first dynamic pressure generating groove 13 as shown by arrow F1', and the sealed fluid F between the sliding surfaces 511, 21 is sucked into the first dynamic pressure generating groove 13 as shown by arrow F2'. On the other hand, the sealed fluid F moves in the second dynamic pressure generating groove 16 as shown by arrow F3', and the sealed fluid F in the second dynamic pressure generating groove 16 mainly flows between the sliding surfaces 11, 21 as shown by arrow F4'.

[0109] At this time, in the first inclined groove portion 531 of the third dynamic pressure generating groove 530, the sealed fluid F moves from the annular groove 19 toward the corner portion 530a as shown by the arrow F5', and in the second inclined groove portion 532, the sealed fluid F moves from the closed end portion on the inner diameter side toward the corner portion 530a as shown by the arrow F6'.

[0110] As a result, the sealed fluid F concentrates at and near the corner 530a, generating positive pressure, and the sealed fluid F in the third dynamic pressure generating groove 530 flows mainly as shown by arrow F7 between the sliding surfaces 511 and 21. This can additionally improve the lubricity between the sliding surfaces 511 and 21.

[0111] Furthermore, since one second inclined groove portion 532 is positioned on the inner diameter side of the corner portion 530a of the adjacent third dynamic pressure generating groove 530 in the forward rotation direction, the sealed fluid F that flows out from the corner portion 530a to between the sliding surfaces 511, 21 is collected in one second inclined groove portion 532 and is less likely to leak into the internal space S1.

[0112] Furthermore, since the first inclined groove portion 531 is shorter than the second inclined groove portion 532, the corner portion 530a of the third dynamic pressure generating groove 530 can be positioned close to the annular groove 19. In other words, since the corner portion 530a can be positioned away from the internal space S1, the sealed fluid F that flows out from the corner portion 530a to between the sliding surfaces 511, 21 is likely to be collected in the second inclined groove portion 532 or the annular groove 19 before reaching the internal space S1, and the sealed fluid F is further less likely to leak into the internal space S1. [Example]

[0113] Next, a mechanical seal as a sliding component according to a sixth embodiment will be described with reference to Fig. 13. Note that a description of the same configuration as in the first embodiment will be omitted.

[0114] The stationary seal ring 610 in the mechanical seal of this embodiment 6 differs from the stationary seal ring 10 of embodiment 1 in that it is provided with a third dynamic pressure generating groove 630, but otherwise has the same configuration as the stationary seal ring 10 of embodiment 1.

[0115] 13, a plurality of third dynamic pressure generating grooves 630 are provided in the circumferential direction on the sliding surface 611 of the stationary seal ring 610 on the inner diameter side of the annular groove 19. The third dynamic pressure generating grooves 630 communicate with the annular groove 19 and extend in the inner diameter direction while inclining in the reverse rotation direction of the rotary seal ring 20, i.e., in the other circumferential direction, from the communicating point.

[0116] When the rotary seal ring 20 rotates relative to the stationary seal ring 610 in the positive direction, a relative negative pressure is generated at the closed end of the third dynamic pressure generating groove 630 and in the vicinity thereof, thereby supplementarily improving the sealing performance between the sliding surfaces 611, 21.

[0117] Furthermore, when the rotary seal ring 20 rotates in the opposite direction relative to the stationary seal ring 610, a positive pressure is generated in the closed end of the third dynamic pressure generating groove 630 and in its vicinity, thereby supplementarily improving the lubrication between the sliding surfaces 611, 21.

[0118] Although the third dynamic pressure generating grooves 630 of this sixth embodiment have been exemplified as extending radially inward from the communicating point of the annular groove 19 while inclining in the reverse rotation direction of the rotary seal ring 20, they may also extend radially inward from the communicating point of the annular groove 19 while inclining in the forward rotation direction of the rotary seal ring 20. In this case, it is possible to supplementarily improve the lubrication during forward rotation of the rotary seal ring 20, and the sealing performance during reverse rotation of the rotary seal ring 20. [Example]

[0119] Next, a mechanical seal as a sliding component according to a seventh embodiment will be described with reference to Fig. 14. Note that a description of the same configuration as that of the first embodiment will be omitted.

[0120] The stationary seal ring 710 in the mechanical seal of this seventh embodiment differs from the stationary seal ring 10 of the first embodiment in that it is provided with a third dynamic pressure generating groove 730, but otherwise has the same configuration as the stationary seal ring 10 of the first embodiment.

[0121] 14, a plurality of third dynamic pressure generating grooves 730 are provided in the circumferential direction on the sliding surface 711 of the stationary seal ring 710 on the inner diameter side of the annular groove 19. The third dynamic pressure generating grooves 730 are dimples that are circular when viewed in the axial direction.

[0122] This causes positive pressure to be generated in the third dynamic pressure generating groove 730 in either rotation direction of the rotary seal ring 20. In other words, the lubrication between the sliding surfaces 711, 21 can be supplementarily improved in either rotation direction of the rotary seal ring 20.

[0123] The third dynamic pressure generating groove 730 is not limited to a circular shape when viewed in the axial direction, but may be an elongated hole having a rectangular or elliptical shape when viewed in the axial direction.

[0124] Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention also includes modifications and additions that do not deviate from the gist of the present invention.

[0125] For example, in the first to seventh embodiments, mechanical seals for automobiles have been used as examples of sliding parts, but other mechanical seals for general industrial machinery and the like may also be used.

[0126] Furthermore, in the above-described Examples 1 to 7, examples have been described in which the first dynamic pressure generating grooves and the second dynamic pressure generating grooves are provided in the stationary seal ring, but the first dynamic pressure generating grooves and the second dynamic pressure generating grooves may be provided in the rotary seal ring, or the first dynamic pressure generating grooves and the second dynamic pressure generating grooves may be provided in one of the stationary seal ring and the rotary seal ring, or in both.

[0127] In addition, in the above-described Examples 1 to 7, examples have been described in which the communicating groove and the annular groove are provided in the stationary seal ring, but the communicating groove and the annular groove may also be provided in the rotary seal ring, or the communicating groove and the annular groove may be provided in one of the stationary seal ring and the rotary seal ring, or in both.

[0128] In addition, in the above-described first to seventh embodiments, the sealed fluid side is the high pressure side and the leakage side is the low pressure side, but the sealed fluid side and the leakage side may be at approximately the same pressure.

[0129] Furthermore, in the first to seventh embodiments, the sealed fluid F has been described as a high-pressure liquid, but it is not limited to this and may be a gas, or may be a mist in which a liquid and a gas are mixed.

[0130] Furthermore, in the above-described Examples 1 to 7, the fluid on the leakage side was described as being the atmosphere A, which is a low-pressure gas, but it is not limited to this and may be a liquid or a high-pressure gas, or may be a mist-like mixture of liquid and gas.

[0131] Furthermore, in Examples 1 to 7, the first and second dynamic pressure generating grooves extend in a curved manner, but the first and second dynamic pressure generating grooves may extend in a straight line.

[0132] Furthermore, in Examples 1 to 7, the first and second dynamic pressure generating grooves have a constant depth, but the bottom surface may be inclined or stepped so that the depth becomes shallower toward the closed end.

[0133] Furthermore, in the above-described first to seventh embodiments, the communicating grooves constituting the conducting grooves extend radially while inclining circumferentially, but as in the stationary seal ring 810 of modified example 1 of embodiment 1 shown in FIG. 15, the communicating groove 818 may extend linearly radially and communicate the annular groove 19 with the outer space S2.

[0134] Furthermore, in the above-described Examples 1 to 7, a land extending in the circumferential direction is provided between the first dynamic pressure generating groove and the second dynamic pressure generating groove, and the closed ends are opposed to each other in the radial direction, but the first dynamic pressure generating grooves 13 and the second dynamic pressure generating grooves 16 may be arranged alternately in the circumferential direction, as in the stationary seal ring 910 of Modification 2 shown in Fig. 16. Furthermore, the closed end of the first dynamic pressure generating groove 13 may be arranged closer to the annular groove 19 than the closed end of the second dynamic pressure generating groove 16.

[0135] Furthermore, in the above-described Examples 1 to 7, the communicating grooves are formed on the sliding surface, but as in the stationary seal ring 100 of Modified Example 3 shown in Fig. 17, the communicating groove 180 may extend inward from the outer peripheral surface of the stationary seal ring 100, and its inner diameter end portion may extend in the axial direction to communicate with the annular groove 19. In this case, the sealed fluid F does not flow in or out of the sliding surface from the communicating groove 180, and the first dynamic pressure generating groove 13 and the second dynamic pressure generating groove 14 are formed in the stationary seal ring 100. 16 These are arranged evenly in the circumferential direction, and dynamic pressure is generated evenly in the circumferential direction.

[0136] Furthermore, in the above-described Examples 1 to 7, a configuration was exemplified in which a plurality of first and second dynamic pressure generating grooves of the same shape were provided in the circumferential direction of the stationary seal ring, but this is not limited thereto, and the stationary seal ring may have, for example, a mixture of spiral grooves as in Example 1 and Rayleigh steps as in Example 3. [Explanation of symbols]

[0137] 1 Rotation axis 2 sleeves 4. Housing 10 Stationary sealing ring 11 Sliding surface 12A Land 13 First dynamic pressure generating groove (spiral groove) 13A End (Closed end) 13B End 16 Second dynamic pressure generating groove (spiral groove) 16B End (Closed end) 17 Conductive Groove 18 Communication groove 19 Annular groove 20 Rotating seal ring 21 Sliding surface 313B 1st Rayleigh Step (1st hydrodynamic groove) 316B 2nd Rayleigh Step (2nd dynamic pressure generating groove) 530 Third dynamic pressure generating groove A. Atmosphere C. Cavitation region F Sealed fluid S1 Inner space (other side space) S2 Outside space (space on one side)

Claims

1. A sliding component having a pair of sliding surfaces arranged opposite to each other at positions that rotate relative to each other when a rotary machine is driven, one sliding surface is provided with a first dynamic pressure generating groove extending in one circumferential direction and communicating with one of the spaces of the inner diameter side space and the outer diameter side space, a second dynamic pressure generating groove extending in the other circumferential direction, and a conducting groove communicating with the space on the one side; the conducting groove includes a groove extending in a circumferential direction and a communicating groove that communicates the groove extending in the circumferential direction with the space on the one side, The second dynamic pressure generating groove is disposed in a space on one side of the groove extending in the circumferential direction and communicates with the groove extending in the circumferential direction.

2. 2. The sliding component according to claim 1, wherein a land extending in a circumferential direction is provided between the first dynamic pressure generating groove and the second dynamic pressure generating groove.

3. 3. The sliding element according to claim 2, wherein the closed end of the first hydrodynamic pressure generating groove and the closed end of the second hydrodynamic pressure generating groove face each other in the radial direction.

4. The sliding element according to claim 1 , wherein the conductive groove has an annular groove as a groove extending in the circumferential direction.

5. 2. The sliding component according to claim 1, wherein the first dynamic pressure generating groove and the second dynamic pressure generating groove are spiral grooves.

6. 6. The sliding component according to claim 5, wherein the communication groove extends so as not to intersect with the first dynamic pressure generating groove and the second dynamic pressure generating groove.

7. 7. A sliding element according to claim 1, wherein a third dynamic pressure generating groove is provided on the other side of the space on the other side of the conductive groove in the pair of sliding surfaces.

8. 8. The sliding component according to claim 7, wherein the third dynamic pressure generating groove is a bent groove that communicates with the conductive groove.

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