Sliding component

1. An eccentric sliding assembly comprising:

a first sliding component having an annular shape with high-pressure and low-pressure fluids facing inside and outside of the sliding component and having a sliding surface;

a second sliding component having a sliding surface;

an eccentric driving device configured to slide the sliding surface of the first sliding component with respect to the sliding surface of the second sliding surface such that a center of the first sliding component imaginarily draws a circle which is eccentric with respect to a center of the second sliding component while keeping a non-rotation state of the first sliding component with respect to the center of the first sliding component in a plan view, or configured to slide the sliding surface of the second sliding component with respect to the sliding surface of the first sliding surface such that a center of the second sliding component imaginarily draws a circle which is eccentric with respect to a center of the first sliding component while keeping a non-rotation state of the second sliding component with respect to the center of the second sliding component in a plan view, wherein

the whole of the sliding surface of the first sliding component is disposed within the sliding surface of the second sliding component in the plan view while the sliding surface of the first sliding component slides relatively to the sliding surface of the second sliding component,

the sliding surface of the first sliding component is provided with a plurality of grooves each having an opening which is open only to a fluid space on any one of an inner diameter side and an outer diameter side of the sliding surface and arranged in a circumferential direction,

each of the grooves is partially defined by a bottom surface, a first side wall surface extending in a circumferential direction and intersecting with the bottom surface and the sliding surface provided with the grooves, and a pair of second side wall surfaces extending from both sides of the bottom surfaces to the opening of each of the grooves in a radial direction and intersecting with the bottom surface and the sliding surface provided with the grooves, and

the first side wall surface is connected to each of the second side wall surfaces.

2. The eccentric sliding assembly according to claim 1 , wherein each of the grooves has a corner portion formed by an end of the first side wall surface and an end of each of the second side wall surfaces, the corner portion being angular.

3. The eccentric sliding assembly according to claim 2 , wherein the first side wall surface is a circular arc surface having a circular center which coincides with a center of the sliding surface provided with the grooves and each of the second side wall surface is a radial surfaces extending from the center of the sliding surface provided with the grooves.

4. The eccentric sliding assembly according to claim 2 , wherein each of the grooves has a circumferential length larger than a radial length thereof.

5. The eccentric sliding assembly according to claim 2 , wherein each of the grooves is open to a space on the inner diameter side.

6. The eccentric sliding assembly according to claim 2 , wherein each of the grooves is open to a space on a high-pressure side.

7. The eccentric sliding assembly according to claim 2 , wherein the first sliding component has a radial width smaller than a radial width of the second sliding component.

8. The eccentric sliding assembly according to claim 1 , wherein the first side wall surface is a circular arc surface having a circular center which coincides with a center of the sliding surface provided with the grooves and each of the second side wall surfaces is a radial surfaces extending from the center of the sliding surface provided with the grooves.

9. The eccentric sliding assembly according to claim 8 , wherein each of the grooves has a circumferential length larger than a radial length thereof.

10. The eccentric sliding assembly according to claim 8 , wherein each of the grooves is open to a space on the inner diameter side.

11. The eccentric sliding assembly according to claim 8 , wherein each of the grooves is open to a space on a high-pressure side.

12. The eccentric sliding assembly according to claim 8 , wherein the first sliding component has a radial width smaller than a radial width of the second sliding component.

13. The eccentric sliding assembly according to claim 1 , wherein each of the grooves has a circumferential length larger than a radial length thereof.

14. The eccentric sliding assembly according to claim 13 , wherein each of the grooves is open to a space on the inner diameter side.

15. The eccentric sliding assembly according to claim 13 , wherein each of the grooves is open to a space on a high-pressure side.

16. The eccentric sliding assembly according to claim 13 , wherein the first sliding component has a radial width smaller than a radial width of the second sliding component.

17. The eccentric sliding assembly according to claim 1 , wherein each of the grooves is open to a space on the inner diameter side.

18. The eccentric sliding assembly according to claim 17 , wherein each of the grooves is open to a space on a high-pressure side.

19. The eccentric sliding assembly according to claim 1 , wherein each of the grooves is open to a space on a high-pressure side.

20. The eccentric sliding assembly according to claim 1 , wherein the first sliding component has a radial width smaller than a radial width of the second sliding component.

21. The eccentric sliding assembly according to claim 1 , wherein at least part of the grooves is open to both of a space on the inner diameter side and a space on the outer diameter side.