Sliding parts

Abstract

The technical problem of the present invention is to provide a sliding component, in which a pair of sliding components with sliding surfaces sliding relative to each other can achieve high sealing performance and low sliding torque even when used in a wide rotation speed range and regardless of the rotation direction. The present invention is a pair of sliding components with sliding surfaces (S) sliding relative to each other, wherein at least one of the sliding surfaces has a recess group (51, 52, 53, 54) formed by arranging a plurality of recesses (11, 12), and the shape of the opening of the recess has a long axis and a short axis that are orthogonal to each other. The present invention comprises: a clockwise recess group (51, 53), wherein the recesses (11, 12) are arranged in the clockwise direction from the inner diameter side of the sliding surface toward the outer diameter side; and a counterclockwise recess group (52, 54), wherein the recesses are arranged in the counterclockwise direction from the inner diameter side of the sliding surface toward the outer diameter side.

Description

Technical Field

[0001] The present invention relates to a pair of sliding parts that slide relative to each other on a sliding surface, such as a mechanical seal, a sliding bearing, or other sliding parts suitable for a sliding portion. In particular, it relates to a sliding part such as a seal ring or a bearing that requires a fluid to be sandwiched between the sliding surfaces to reduce friction and prevent the fluid from leaking from the sliding surfaces. Background Art

[0002] As a sealing device for preventing leakage of a sealed fluid, a sealing device (e.g., a mechanical seal) consisting of a pair of sliding parts that slide relative to each other on a sliding surface is known. In such a sealing device, a fluid lubricating film formed by the sealed fluid needs to be formed between the sliding surfaces to reduce the sliding torque and maintain high sealing performance. In addition, as a method for achieving high sealing performance and low sliding torque, a technology of arranging a plurality of dimples on a sliding surface is known.

[0003] For example, it is known that high sealing performance and low sliding torque can be achieved by arranging recesses having circular openings on a sliding surface so as to be arranged on a virtual circle centered on the rotation center of the sliding member (for example, see Patent Document 1).

[0004] In addition, it is known that: a recess having an opening portion with a semicircular end and an elongated rectangular shape is arranged at a specified recess angle θ, and a ratio L1 / L2 of a circumferential length L1 of a recess on a circle passing through the center of the recess to a circumferential length L2 of a table portion between adjacent recesses on the circle is set to 0.001≤L1 / L2≤0.1, thereby optimizing the sealing performance and sliding torque of the entire recess (for example, refer to patent document 2).

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2010-133496

[0008] Patent Document 2: Japanese Patent No. 5456772 Summary of the invention

[0009] Problems to be solved by the invention

[0010] In the technology of Patent Document 1, even if high sealing performance and low sliding torque can be achieved under specific operating conditions, high sealing performance and low sliding torque cannot be achieved over a wide rotation speed range.

[0011] In addition, in the technology of Patent Document 2, since the angle of the recess is fixed, even if the leakage of the sealed fluid can be reduced and the sliding torque can be reduced under specific operating conditions, high sealing performance and low sliding torque cannot be achieved in a wide rotation speed range. In particular, there is a tendency for sealing performance to decrease and sliding torque to increase when used in reverse.

[0012] An object of the present invention is to provide a sliding component that can achieve high sealing performance and low sliding torque even when used in a wide rotation speed range and regardless of the rotation direction in a pair of sliding components whose sliding surfaces slide relative to each other.

[0013] Solutions for solving problems

[0014] In order to solve the above-mentioned problems, the sliding component of the present invention is a pair of sliding components whose sliding surfaces slide relative to each other, characterized in that:

[0015] At least one of the sliding surfaces has a recess group formed by arranging a plurality of recesses, wherein the shape of the opening of the recess has a major axis and a minor axis that are orthogonal to each other,

[0016] The recess group includes: a clockwise recess group, in which the recesses are arranged in a clockwise direction from the inner diameter side to the outer diameter side of the sliding surface; and a counterclockwise recess group, in which the recesses are arranged in a counterclockwise direction from the inner diameter side to the outer diameter side of the sliding surface.

[0017] According to this feature, since the clockwise recessed group extending from the inner diameter side to the outer diameter side of the sliding surface and the counterclockwise recessed group extending from the inner diameter side to the outer diameter side of the sliding surface are provided, high sealing performance and low sliding torque can be achieved regardless of the rotation direction.

[0018] The sliding component of the present invention is characterized in that:

[0019] The clockwise recessed hole group includes a first recessed hole group in which the long axes of the recessed holes are aligned, and the counterclockwise recessed hole group includes a second recessed hole group in which the long axes of the recessed holes are aligned.

[0020] According to this feature, the first recessed hole group of the clockwise recessed hole group and the second recessed hole group of the counterclockwise recessed hole group respectively arrange the long axes of the recessed holes neatly, thereby making it easy to adjust the strength of the suction effect and dynamic pressure effect of the recessed holes. Furthermore, as a whole, the recessed hole group can exhibit high sealing performance and low sliding torque within a wide rotation speed range.

[0021] The sliding component of the present invention is characterized in that:

[0022] The clockwise recessed group further includes a third recessed group in which the minor axes of the recessed holes constituting the second recessed group are aligned, and the counterclockwise recessed group further includes a fourth recessed group in which the minor axes of the recessed holes constituting the first recessed group are aligned.

[0023] According to this feature, the clockwise recess group further includes a third recess group in which the short axes are arranged in a neat arrangement, and the counterclockwise recess group further includes a fourth recess group in which the short axes are arranged in a neat arrangement. Therefore, the first to fourth recess groups having different characteristics can be combined to easily adjust the strength of the suction effect and the dynamic pressure effect. Furthermore, as a whole, the recess group can exhibit high sealing performance and low sliding torque within a wide rotation speed range.

[0024] The sliding component of the present invention is characterized in that:

[0025] The recesses constituting the first recess group and the recesses constituting the second recess group are different in depth.

[0026] According to this feature, the depths of the recesses constituting the first recess group and the recesses constituting the second recess group are different, so the strengths of the suction effect and the dynamic pressure effect of the first to fourth recess groups can be easily changed. Therefore, as a whole, the recess group can exhibit high sealing performance and low sliding torque within a wide rotation speed range.

[0027] The sliding component of the present invention is characterized in that

[0028] The first recess group forms a convex curve toward the radial outer side of the sliding surface, and the second recess group forms a convex curve toward the radial outer side of the sliding surface.

[0029] According to this feature, since the pockets are arranged along the curve, the angle of the pockets can be gradually changed, and the pocket group as a whole can exhibit high sealing performance and low sliding torque in a wide rotation speed range.

[0030] The sliding component of the present invention is characterized in that:

[0031] The opening of the cavity is in the shape of an ellipse.

[0032] According to this feature, even if the recess having an elliptical opening is an ellipse of the same shape and size, the suction effect or the dynamic pressure effect can be enhanced by changing the inclination of the long axis of the recess. Therefore, by configuring the recess with the inclination of the long axis of the recess changed, high sealing performance and low sliding torque can be achieved within a wide rotational speed range. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a longitudinal sectional view showing an example in which the sliding component of the present invention is applied to a mechanical seal.

[0034] Figure 2 yes Figure 1 The WW arrow view of FIG. 1 is a diagram showing an example of a sliding surface of the sliding member according to the first embodiment of the present invention.

[0035] Figure 3 yes Figure 1 The WW arrow view of FIG. 1 is a diagram showing an example of a sliding surface of a sliding member according to the second embodiment of the present invention.

[0036] Figure 4 yes Figure 1 The WW view of FIG. 1 is a diagram showing an example of a sliding surface of a sliding member according to the third embodiment of the present invention.

[0037] Figure 5 yes Figure 1 The WW arrow view of FIG. 1 is a diagram showing an example of a sliding surface of a sliding component according to the fourth embodiment of the present invention.

[0038] Figure 6 It is a figure which shows another example of the recess of this invention. DETAILED DESCRIPTION

[0039] Hereinafter, with reference to the accompanying drawings, the method for implementing the present invention is exemplarily described based on the embodiments. Among them, unless otherwise specifically stated, the size, material, shape, relative arrangement of the components described in the present embodiment do not mean that the scope of the present invention is limited to this.

[0040] Example 1

[0041] Reference Figure 1 and Figure 2 , the sliding component of the first embodiment of the present invention is described. In the following embodiment, a mechanical seal is used as an example of a sliding component for description, but it is not limited to this. For example, it can also be used as a sliding component of a bearing that slides with a rotating shaft while sealing lubricating oil on one axial side of a cylindrical sliding surface. It should be noted that the outer peripheral side of the sliding component constituting the mechanical seal is set as the sealed fluid side (high-pressure fluid side), and the inner peripheral side is set as the leakage side (low-pressure fluid side, such as the atmosphere side) for description.

[0042] Figure 11 is a longitudinal sectional view showing an example of a mechanical seal 1, which is an inside type mechanical seal that seals a sealed fluid that leaks from the outer periphery of a sliding surface S toward the inner periphery, and is composed of a rotating side cartridge and a fixed side cartridge. The rotating side cartridge includes: a sleeve 2 that is fitted to a rotating shaft 10; an annular rotating side seal ring 3 that is a sliding member on one side; and a packing 8 that seals between the sleeve 2 and the rotating side seal ring 3, and the rotating side cartridge rotates together with the rotating shaft 10.

[0043] The fixed side cylinder comprises: a housing 4, which is assembled on a casing 9; a circular fixed side sealing ring 5, which is a sliding component on the other side; a bellows 7, which seals between the fixed side sealing ring 5 and the housing 4; and a helical corrugated spring 6, which applies force to the fixed side sealing ring 5 toward the rotating side sealing ring 3 via the bellows 7, and the housing 4 is fixed relative to the casing 9 in the rotational direction and the axial direction.

[0044] In the mechanical seal 1 having the above structure, the sliding surface S of the rotating side seal ring 3 and the sliding surface S of the fixed side seal ring 5 slide against each other to prevent the sealed fluid from flowing out from the outer peripheral side to the inner peripheral side. Figure 1 In the figure, the width of the sliding surface of the rotating side seal ring 3 is shown to be wider than the width of the sliding surface of the fixed side seal ring 5, but the invention is not limited to this and it is obvious that the invention can also be applied to the opposite case.

[0045] The material of the rotating side seal ring 3 and the stationary side seal ring 5 is selected from silicon carbide (SiC) which is excellent in wear resistance and carbon which is excellent in self-lubricating property. For example, both of them can be SiC or the rotating side seal ring 3 can be SiC and the stationary side seal ring 5 can be carbon.

[0046] like Figure 2 As shown, the sliding surface S of the fixed side seal ring 5 is provided with a clockwise recessed group 51, 53 and a counterclockwise recessed group 52, 54. The recessed groups 11, 12 have substantially the same size and the same depth. The recessed groups 51, 54 are composed of a plurality of recessed groups 11, and the recessed groups 52, 53 are composed of a plurality of recessed groups 12. The recessed groups 51, 52, 53, 54 are respectively composed of the same number of recessed groups.

[0047] In the present invention, the recesses 11 and 12 refer to recesses having an opening surrounded by a flat sliding surface S and a bottom recessed from the sliding surface S, and the openings 11a and 12a of the recesses are formed by a shape having an orthogonal major axis L and a minor axis K. In addition, the recesses 11 and 12 are arranged separately from each other via a land portion R. In the present invention, the major axis is a virtual line that passes through the centroid of the shape of the opening and connects the maximum width portion of the opening. In addition, the minor axis is a virtual line that passes through the centroid and connects the openings in a manner orthogonal to the major axis. With regard to the openings of the recesses 11 and 12 in this embodiment, an ellipse having an orthogonal major axis L and a minor axis K is used as an example. However, it is not limited to an ellipse, and as long as it is a shape having an orthogonal major axis L and a minor axis K, it may also be an oval shape, a rhombus, a polygon, or the like. Figure 6 The shape shown is composed of arbitrary closed curves 91, 92, 93, 94.

[0048] like Figure 2 As shown, in the pocket group 51, the major axis L of the pocket 11 is arranged along a virtual spiral SP1 and tangentially thereto, and the pockets 11 are arranged at equal intervals in a predetermined number (in Figure 2In the example of 7). In the pocket group 53, the minor axis K of the pocket 12 is arranged so as to be tangent to the virtual spiral SP3, and the same number of pockets 12 as the pockets 11 are arranged at equal intervals so as to form a spiral SP3 in the clockwise direction from the inner diameter side to the outer diameter side of the sliding surface S. Furthermore, the pocket group 51 and the pocket group 53 are arranged on the sliding surface S at equal intervals and staggered in an alternating manner in the circumferential direction. Here, staggered arrangement means that when the pocket group 51 and the pocket group 53 are arranged in a manner adjacent to each other in the circumferential direction, the major axis L of the pocket 12 arranged in a regular arrangement with the minor axis K is located between the pockets 11 and the pockets 11 arranged in a regular arrangement with the major axis L. In addition, in the pocket group 52, the major axis L of the pocket 12 is arranged so as to be tangent to the virtual spiral SP2, and the pocket 12 is arranged so as to form a spiral SP2 in the counterclockwise direction from the inner diameter side to the outer diameter side of the sliding surface S. In the pocket group 54, the minor axis K of the pocket 11 is arranged along the virtual spiral SP4 and is tangential thereto, and the pocket 11 is arranged so as to form the spiral SP4 in the counterclockwise direction from the inner diameter side to the outer diameter side of the sliding surface S. The major axis L of the pocket 11 is formed to be tangential to the virtual spiral SP1, the minor axis K of the pocket 11 is formed to be tangential to the virtual spiral SP4, the major axis L of the pocket 12 is formed to be tangential to the virtual spiral SP2, and the minor axis K of the pocket 12 is formed to be tangential to the virtual spiral SP3. In addition, in the sliding surface S, the clockwise pocket group 51 and the pocket group 53 are alternately arranged in the circumferential direction, and the counterclockwise pocket group 52 and the pocket group 54 are alternately arranged in the circumferential direction.

[0049] The number of the recesses 11 constituting the clockwise recess group 51 is the same as the number of the recesses 11 constituting the counterclockwise recess group 54, and they are symmetrical with respect to the radial axis passing through the middle of the recess group 51 and the recess group 54. In addition, the number of the recesses 12 constituting the counterclockwise recess group 52 is the same as the number of the recesses 12 constituting the clockwise recess group 53, and they are symmetrical with respect to the radial axis passing through the middle of the recess group 52 and the recess group 53.

[0050] The function of each of the recesses 11 and 12 will be described. When the rotating side seal ring 3 rotates in the clockwise direction, the fluid between the sliding surface S and the fluid in the recesses 11 and 12 follow the moving direction of the rotating side seal ring 3 due to their viscosity. For the fluid flowing into the recesses 11 and 12, the flow path is rapidly expanded, so negative pressure is formed on the upstream side of the recesses 11 and 12, and cavitation is generated. However, the magnitude of the negative pressure in the cavitation is limited by the value of the vapor pressure of the fluid, so it will not become a large negative pressure. In addition, on the downstream side of the recesses 11 and 12, the flow path is rapidly reduced, thereby generating a positive pressure through the wedge effect (dynamic pressure effect). Through the negative pressure generated on the upstream side of the recesses 11 and 12, the recesses 11 and 12 exert a suction effect to suck in the surrounding fluid. On the other hand, the magnitude of the positive pressure generated on the downstream side of the recesses 11 and 12 is greater than the magnitude of the negative pressure in the cavitation, so the recesses 11 and 12 are formed as a whole. Positive pressure. The positive pressure generated by the plurality of recesses 11 and 12 disposed on the sliding surface S pushes the sliding surfaces S apart, and the fluid flows into the sliding surface S, thereby obtaining a lubricating function.

[0051] Next, the functions of the recess groups 51, 52, 53, and 54 are described. When the rotating side seal ring 3 rotates clockwise, the recesses 11 and 12 near the leakage side periphery 5a of the clockwise recess groups 51 and 53 play a pumping function of sucking fluid from the leakage side. In addition, between adjacent recesses 11 and 12, suction and discharge are repeated continuously, and the fluid gradually moves from the leakage side to the sealed fluid side, so that leakage can be greatly reduced. Moreover, high-pressure fluid is supplied to the sliding surface S through the dynamic pressure effect of the recesses 11 and 12, so for the sliding surface S, the fluid lubrication state is maintained, which can reduce the sliding torque.

[0052] In addition, the clockwise recessed group 51 is configured to form the spiral SP1 by connecting the long axes L of the recessed 11 to each other, while the clockwise recessed group 53 is configured to form the spiral SP3 by connecting the short axes K of the recessed 12 to each other. Therefore, even if the clockwise recessed groups 51 and 53 are the same, their pumping effect and fluid lubrication effect are different. Specifically, the clockwise recessed group 51 in which the long axes L of the recessed 11 are arranged in a row to form the spiral SP1 has a high dynamic pressure generation effect, and thus the fluid lubrication function is exerted even at a low rotation speed. On the other hand, the clockwise recessed group 53 in which the short axes K of the recessed 12 are arranged in a row to form the spiral SP3 has a high suction effect, and thus the pumping function is exerted even at a low rotation speed. Therefore, even if the operation is carried out in a wide rotation speed range, the clockwise recessed groups 51 and 53 complement each other's functions and can exert a high fluid lubrication function and sealing function.

[0053] On the contrary, when the rotating side seal ring 3 rotates counterclockwise, the recesses 11 and 12 near the leakage side periphery 5a of the counterclockwise recess groups 52 and 54 play a pumping function of sucking fluid from the leakage side. In addition, between adjacent recesses 11 and 12, suction and discharge are continuously repeated, and the fluid gradually moves from the leakage side to the sealed fluid side, so that leakage can be greatly reduced. Moreover, high-pressure fluid is supplied to the sliding surface S through the dynamic pressure effect of the recesses 11 and 12, so for the sliding surface S, the fluid lubrication state is maintained, which can reduce the sliding torque.

[0054] In addition, the counterclockwise recessed group 52 is configured to connect the long axes L of the recessed holes 12 to form the spiral SP2, while the counterclockwise recessed group 54 is configured to connect the short axes K of the recessed holes 11 to form the spiral SP4. Therefore, even if the counterclockwise recessed groups 52 and 54 are the same, their pumping effect and fluid lubrication effect are different. Specifically, the counterclockwise recessed group 52, which forms the spiral SP2 by arranging the long axes L of the recessed holes 12 in a row, has a high dynamic pressure generation effect, and thus can exert a fluid lubrication function even at a low rotation speed. On the other hand, the counterclockwise recessed group 54, which forms the spiral SP4 by arranging the short axes K of the recessed holes 11 in a row, has a high suction effect, and thus can exert a pumping function even at a low rotation speed. Therefore, even if the operation is carried out in a wide rotation speed range, the counterclockwise recessed groups 52 and 54 complement each other's functions and can exert a high fluid lubrication function and sealing function.

[0055] In this way, the clockwise recess group 51 and the counterclockwise recess group 54 as well as the counterclockwise recess group 52 and the clockwise recess group 53 are set to be symmetrical with respect to the radial direction. Thus, the clockwise recess group and the counterclockwise recess group are provided, so that high sealing performance and low sliding torque can be achieved regardless of the rotation direction.

[0056] As mentioned above, although the embodiment of the present invention is described with reference to the drawings, the specific configuration is not limited to the embodiment, and even if there are changes and additions within the scope that does not depart from the gist of the present invention, they are also included in the present invention.

[0057] In the above embodiment, the shapes and sizes of the recesses 11 and 12 are substantially the same, but the present invention is not limited thereto. For example, the clockwise recess groups 51 and 53 and the counterclockwise recess groups 52 and 54 may be formed by recesses 11 and 12 having different depths. By changing the depth of the recesses, the fluid retention effect, suction effect, and dynamic pressure effect of retaining the fluid in the recesses can be changed. Therefore, by configuring recesses with different depths, high sealing performance and low sliding torque can be achieved even at a wider rotation speed.

[0058] In addition, the recessed pockets 11 and 12 are arranged in a spiral manner in the recessed pocket groups 51, 52, 53, and 54, but instead of a spiral, a radially outwardly convex curve such as an arc, a parabola, a sine wave, a trochoid, etc., or a straight line extending in a clockwise or counterclockwise direction from the inner diameter side toward the outer diameter side of the sliding surface S may be used. In addition, a curve and a straight line may be combined.

[0059] Example 2

[0060] A sliding component according to a second embodiment of the present invention will be described. Figure 3 The sliding surface S of the sliding member of the second embodiment is shown, which is different from the first embodiment in that the number of the recesses 15 and 16 constituting the clockwise recess groups 55 and 56 is different from the number of the recesses 15 and 16 constituting the counterclockwise recess groups 57 and 58. The other configurations are the same as those of the first embodiment. Hereinafter, the same reference numerals are attached to the same components and configurations as those of the first embodiment, and repeated descriptions are omitted.

[0061] like Figure 3 As shown, the sliding surface S of the fixed side sealing ring 5 is provided with a clockwise recessed hole group 55, 56 in which a plurality of recessed holes 15, 16 are arranged in a clockwise direction from the inner diameter side of the sliding surface S toward the outer diameter side, and a counterclockwise recessed hole group 57, 58 in which a plurality of recessed holes 15, 16 are arranged in a counterclockwise direction from the inner diameter side of the sliding surface S toward the outer diameter side.

[0062] like Figure 3 As shown, in the clockwise recess group 55, the major axis L of the recess 15 is arranged along the virtual spiral SP5 at a predetermined angle, and the recess 15 is arranged in a predetermined number (in the range of 1 to 500) at equal intervals so as to form a clockwise spiral SP5 from the inner diameter side of the sliding surface S toward the outer diameter side. Figure 3 In the example, the number of the concave holes 16 is 13. In the clockwise concave hole group 56, the minor axis K of the concave hole 16 is arranged along the virtual spiral SP6 at a predetermined angle, and the concave hole 16 is arranged to form the clockwise spiral SP6 from the inner diameter side of the sliding surface S to the outer diameter side. In the counterclockwise concave hole group 57, the minor axis K of the concave hole 15 is arranged along the virtual spiral SP7 at a predetermined angle, and the concave hole 15 is arranged in a predetermined number (in the counterclockwise spiral SP7) from the inner diameter side of the sliding surface S to the outer diameter side. Figure 3In the example of the counterclockwise recessed pocket group 58, the major axis L of the recessed pocket 16 is arranged along the virtual spiral SP8 at a predetermined angle, and the recessed pocket 16 is arranged to form the counterclockwise spiral SP8 from the inner diameter side to the outer diameter side of the sliding surface S. In addition, in the sliding surface S, the clockwise recessed pocket group 55 and the recessed pocket group 56 are alternately arranged in the circumferential direction, and the counterclockwise recessed pocket group 57 and the recessed pocket group 58 are alternately arranged in the circumferential direction.

[0063] When the rotating side seal ring 3 rotates clockwise, the clockwise recessed hole groups 55 and 56 play a sealing function and a fluid lubricating function, which can reduce leakage and reduce sliding torque. On the contrary, when the rotating side seal ring 3 rotates counterclockwise, the counterclockwise recessed hole groups 57 and 58 play a sealing function and a fluid lubricating function, which can reduce leakage and reduce sliding torque.

[0064] The number of the recesses 15 and 16 constituting the clockwise recess groups 55 and 56 is greater than the number of the recesses 15 and 16 constituting the counterclockwise recess groups 57 and 58, so that the sealing function and the fluid lubrication function during clockwise rotation can be improved. In addition, the angle θ1 formed by the spirals SP5 and SP6 and the leakage side peripheral edge 5a is smaller than the angle θ2 formed by the spirals SP7 and SP8 and the leakage side peripheral edge 5a, so that during clockwise rotation, the clockwise recess groups 55 and 56 can exert a pumping effect from a low rotation speed. In particular, it is effective when the operating speed range during clockwise rotation reaches a low speed rotation.

[0065] In the sliding component of Example 1, the number of the recesses 11 and 12 constituting the clockwise recess groups 51 and 53 is the same as the number of the recesses 11 and 12 constituting the counterclockwise recess groups 52 and 54, so the same sealing function and fluid lubrication function are exerted during clockwise rotation and counterclockwise rotation. On the other hand, in the sliding component of Example 2, the number of the recesses 15 and 16 constituting the clockwise recess groups 55 and 56 is greater than the number of the recesses 15 and 16 constituting the counterclockwise recess groups 57 and 58, so the sealing function and fluid lubrication function can be improved during clockwise rotation compared to counterclockwise rotation. Furthermore, since the angle θ1 formed by the spirals SP5 and SP6 and the leakage side peripheral edge 5a is smaller than the angle θ2 formed by the spirals SP7 and SP8 and the leakage side peripheral edge 5a, the clockwise recessed groups 55 and 56 can exert a pumping effect at a lower rotation speed than the counterclockwise recessed groups 57 and 58.

[0066] Example 3

[0067] A sliding component according to a third embodiment of the present invention will be described. Figure 4The sliding surface S of the sliding member of the third embodiment is shown. In the first embodiment, the clockwise recessed group 51 and the clockwise recessed group 53 are arranged alternately in the circumferential direction in the same number, but in the third embodiment, the number of the clockwise recessed group 61 and the number of the clockwise recessed group 62 are arranged differently from the first embodiment. The other configurations are the same as those of the first embodiment. Hereinafter, the same reference numerals are attached to the same components and configurations as those of the first embodiment, and repeated descriptions are omitted.

[0068] like Figure 4 As shown, the sliding surface S of the fixed side sealing ring 5 is provided with a clockwise recessed hole group 61, 62 in which a plurality of recessed holes 19, 20 are arranged in a clockwise direction from the inner diameter side toward the outer diameter side of the sliding surface S, and a counterclockwise recessed hole group 59, 60 in which a plurality of recessed holes 19, 20 are arranged in a counterclockwise direction from the inner diameter side toward the outer diameter side of the sliding surface S.

[0069] like Figure 4 As shown, in the clockwise recess group 61, the major axis L of the recess 19 is arranged along a virtual spiral SP9 and tangentially thereto, and the recess 19 is arranged in a predetermined number (in the range of 100 to 1000) at equal intervals so as to form a clockwise spiral SP9 from the inner diameter side to the outer diameter side of the sliding surface S. Figure 4 In the example, the number of the concave holes 20 is 6. In the clockwise concave hole group 62, the minor axis K of the concave hole 20 is arranged so as to be tangent to the virtual spiral SP10, and the concave hole 20 is arranged to form a clockwise spiral SP10 from the inner diameter side to the outer diameter side of the sliding surface S. In the counterclockwise concave hole group 59, the major axis L of the concave hole 20 is arranged so as to be tangent to the virtual spiral SP12, and the counterclockwise concave hole group 59 is arranged in a predetermined number (in the range of 1 to 600) so as to form a counterclockwise spiral SP12 from the inner diameter side to the outer diameter side of the sliding surface S. Figure 4 In the example of the counterclockwise recessed pocket group 60, the minor axis K of the recessed pocket 19 is arranged so as to be tangential to the virtual spiral SP11, and the recessed pocket 19 is arranged to form a clockwise spiral SP11 from the inner diameter side to the outer diameter side of the sliding surface S. Furthermore, in the sliding surface S, three consecutive recessed pocket groups 61, one recessed pocket group 62, one recessed pocket group 61, and one recessed pocket group 62 are arranged in sequence in the circumferential direction.

[0070] When the rotating side seal ring 3 rotates clockwise, the clockwise recessed hole groups 61 and 62 play a sealing function and a fluid lubrication function, which can reduce leakage and reduce sliding torque. On the contrary, when the rotating side seal ring 3 rotates counterclockwise, the recessed hole groups 59 and 60 extending in the counterclockwise direction play a sealing function and a fluid lubrication function, which can reduce leakage and reduce sliding torque. However, the number of the clockwise recessed hole groups 61 is large, so the sealing function and the fluid lubrication function can be improved when rotating in the clockwise direction compared with when rotating in the counterclockwise direction.

[0071] The sliding component of Example 1 alternately arranges the same number of clockwise recess groups 51 and clockwise recess groups 53 in the circumferential direction. In contrast, the sliding component of Example 3 arranges a large number of clockwise recess groups 61, and is therefore effective when the frequency of clockwise rotation is high.

[0072] Example 4

[0073] A sliding component according to a fourth embodiment of the present invention will be described. Figure 5 The sliding surface S of the sliding member of the fourth embodiment is shown, and is different in that the adjacently arranged clockwise recessed groups 63, 64, 65 are composed of different recessed holes 24, 25, 26. Hereinafter, the same reference numerals are attached to the same components and configurations as those of the first embodiment, and repeated descriptions are omitted.

[0074] like Figure 5 As shown, the sliding surface S of the fixed side seal ring 5 is provided with a clockwise recessed group 63, 64, 65 in which a plurality of recessed holes 24, 25, 26 are arranged in the clockwise direction from the inner diameter side to the outer diameter side of the sliding surface S, and a counterclockwise recessed group 66 in which a plurality of recessed holes 24 are arranged in the counterclockwise direction from the inner diameter side to the outer diameter side of the sliding surface S. The recessed holes 24, 25, 26 are different in at least one of their size, depth, and recessed angle, and the characteristics of each recessed hole are different. The recessed angle refers to the angle formed by the radial axis passing through the intersection of the major axis L and the minor axis K and the major axis L.

[0075] like Figure 5 As shown, in the clockwise recess group 63, the major axis L of the recess 24 is arranged along the virtual spiral SP13 at a predetermined angle, and the recess 24 is arranged in a predetermined number (in the range of 1 to 60 degrees) at equal intervals so as to form a clockwise spiral SP13 from the inner diameter side of the sliding surface S toward the outer diameter side. Figure 5In the example of the embodiment, there are 6). In the clockwise direction recess group 64, the short axis K of the recess 25 is arranged along the spiral SP14 at a predetermined angle, and the recess 25 is arranged to form a clockwise spiral SP14 from the inner diameter side to the outer diameter side of the sliding surface S. In the clockwise direction recess group 65, the short axis K of the recess 26 is arranged along the virtual spiral SP15 at a predetermined angle, and the recess 26 is arranged to form a clockwise spiral SP15 from the inner diameter side to the outer diameter side of the sliding surface S. In the counterclockwise direction recess group 66, the short axis of the recess 27 is arranged along the virtual spiral SP16 at a predetermined angle, and the recess 27 is arranged to form a counterclockwise spiral SP16 from the inner diameter side to the outer diameter side of the sliding surface S. In addition, the clockwise direction recess groups 65, 63, and 64 are arranged in sequence in the circumferential direction. Here, the shapes of the recesses 24, 25, and 26 constituting the clockwise recess group 63, the recesses 25, and 26 constituting the clockwise recess group 64 are the same, but the angles of the recesses relative to the major axis L or the minor axis K are different. Thus, the sealing efficiency and the lubrication efficiency of the clockwise recess groups 63, 64, and 65 can be configured to be the highest at different rotation speeds. That is, the clockwise recess groups 63, 64, and 65 exert high sealing and fluid lubrication functions at different rotation speeds, so that the mechanical seal 1 can exert high sealing and fluid lubrication functions even when used in a wide rotation speed range.

[0076] As mentioned above, although the embodiment of the present invention is described with reference to the drawings, the specific structure is not limited to these embodiments, and even if there are changes and additions within the scope that does not depart from the gist of the present invention, they are also included in the present invention.

[0077] In the above embodiment, the outer peripheral side is set as the sealed fluid side and the inner peripheral side is set as the leakage side, but it is not limited to this. It can also be applied when the inner peripheral side is the sealed fluid side and the outer peripheral side is the leakage side. In addition, the recess group is formed by arranging the major axis or the minor axis of the recess along a spiral, but it is not limited to this. For example, the recess group can also be arranged along a curve such as a parabola, a trochoid, a sine curve, etc.

[0078] Description of Reference Numerals

[0079] 1: Mechanical seal;

[0080] 2: Sleeve;

[0081] 3: Rotating side sealing ring;

[0082] 4: Shell;

[0083] 5: Fixed side sealing ring;

[0084] 5a: leakage side periphery;

[0085] 6: Spiral corrugated spring;

[0086] 7: Bellows;

[0087] 8: Filler;

[0088] 9: Box;

[0089] 10: Rotation axis;

[0090] 11: concave;

[0091] 11a: opening;

[0092] 12: Concave;

[0093] 12a: opening;

[0094] 15: Concave;

[0095] 16: Concave;

[0096] 21: concave;

[0097] 22: Concave;

[0098] 24: Concave;

[0099] 25: concave;

[0100] 26: Concave;

[0101] 51: clockwise concave group (first concave group);

[0102] 52: counterclockwise concave group (second concave group);

[0103] 53: clockwise concave group (third concave group);

[0104] 54: counterclockwise concave group (the fourth concave group);

[0105] 55: clockwise concave group;

[0106] 56: clockwise concave group;

[0107] 57: counterclockwise concave group;

[0108] 58: counterclockwise concave group;

[0109] 59: counterclockwise concave group;

[0110] 60: counterclockwise concave group;

[0111] 61: clockwise concave group;

[0112] 62: clockwise concave group;

[0113] 63: clockwise concave group;

[0114] 64: clockwise concave group;

[0115] 65: clockwise concave group;

[0116] 66: counterclockwise concave group;

[0117] 91: Closed curve;

[0118] 92: Closed curve;

[0119] 93: Closed curve;

[0120] 94: Closed curve;

[0121] K: short axis;

[0122] L: long axis;

[0123] R: countertop;

[0124] S: sliding surface;

[0125] S: concave sliding surface;

[0126] θ: cavity angle;

[0127] θ1: angle;

[0128] θ2: angle.

Claims

1. A sliding component, which is a pair of annular sliding components that slide relative to each other on sliding surfaces, characterized in that: At least one of the sliding surfaces has a recess group consisting of a plurality of recesses, wherein the shapes of the openings of the plurality of recesses have orthogonal major and minor axes, The recess groups include: a clockwise recess group, including a first recess group and a third recess group; and a counterclockwise recess group, including a second recess group and a fourth recess group. The first recess group is a collection of a plurality of recesses, wherein the major axis of the recess is inclined clockwise at an angle greater than 0 degrees and less than 90 degrees relative to a radial axis passing through an intersection of the major axis and the minor axis of the recess belonging to the first recess group and a rotation center of the one sliding surface, and a first curve formed by connecting the end points of the major axes of the plurality of recesses belonging to the first recess group is a curve that extends in a clockwise manner as it turns from the inner diameter side toward the outer diameter side of the one sliding surface and has a constant convex direction in the entire radial region of the one sliding surface, The second recess group is a collection of a plurality of recesses, wherein the major axis of the recess is inclined counterclockwise at an angle greater than 0 degrees and less than 90 degrees relative to a radial axis passing through the intersection of the recesses belonging to the second recess group and the rotation center, and a second curve formed by connecting the end points of the major axes of the plurality of recesses belonging to the second recess group is a curve that extends in a counterclockwise manner as it turns from the inner diameter side toward the outer diameter side of the one sliding surface and has a constant convex direction in the entire radial direction of the one sliding surface, The third recessed pocket group is a collection of a plurality of recessed pockets, wherein the third recessed pocket group is composed of the recessed pockets belonging to the second recessed pocket group, and a third curve formed by connecting the end points of the short axes of the plurality of recessed pockets belonging to the third recessed pocket group is a curve that extends in a clockwise manner from the inner diameter side toward the outer diameter side of the one sliding surface and has a constant convex direction in the entire radial direction of the one sliding surface, The fourth recessed hole group is a collection of the plurality of recessed holes, wherein the fourth recessed hole group is composed of the recessed holes belonging to the first recessed hole group, and a fourth curve formed by connecting the end points of the short axes of the plurality of recessed holes belonging to the fourth recessed hole group is a curve that extends in a counterclockwise manner as it turns from the inner diameter side toward the outer diameter side of the one sliding surface and has a fixed convex direction in the entire radial area of ​​the one sliding surface.

2. The sliding component according to claim 1, characterized in that The recesses constituting the first recess group and the recesses constituting the second recess group are different in depth.

3. The sliding component according to claim 1 or 2, characterized in that: The first recess group is configured such that the major axes of the recesses belonging to the first recess group are arranged along the first curve. The second recess group is configured such that the major axes of the recesses belonging to the second recess group are arranged along the second curve. The third recess group is configured such that the minor axes of the recesses belonging to the third recess group are arranged along the third curve. The fourth recessed hole group is configured such that the minor axes of the recessed holes belonging to the fourth recessed hole group are arranged along the fourth curve.

4. The sliding component according to claim 3, characterized in that: The first curve, the second curve, the third curve, and the fourth curve are formed in a spiral shape.

5. The sliding component according to claim 1 or 2, characterized in that: The opening of the cavity is in the shape of an ellipse.

6. The sliding component according to claim 1 or 2, characterized in that: The plurality of recesses belonging to the first recess group are arranged at equal intervals along the first curve, The plurality of recesses belonging to the second recess group are arranged at equal intervals along the second curve, The plurality of recesses belonging to the third recess group are arranged at equal intervals along the third curve. The plurality of recesses belonging to the fourth recess group are arranged at equal intervals along the fourth curve.

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