Sliding member
A pair of sliding members sliding relative to each other at sliding faces is configured such that at least one of the sliding faces includes a negative pressure generation mechanism separated from a leakage side by a leakage-side land portion and a land portion arranged in the negative pressure generation mechanism. In the compact sliding members, sliding torque can be reduced and a sealing function can be maintained.
1. A pair of sliding members sliding relative to each other at sliding faces, wherein at least one of the sliding faces includes a negative pressure generation mechanism and a land portion arranged in the negative pressure generation mechanism, wherein
the negative pressure generation mechanism includes an opening end portion which is open to a sealed fluid side, a closed end portion which is closed with respect to the sealed fluid side and a leakage side, and a negative pressure generation groove portion which is disposed between the opening end portion and the closed end portion to be separated from the sealed fluid side and the leakage side by an outer diameter side land portion and an inner diameter side land portion,
the land portion arranged in the negative pressure generation mechanism is an island-shaped land portion surrounded by the negative pressure generation groove portion and separated from the outer dimeter side land portion and the inner diameter side land portion.
2. The sliding members according to claim 1 , wherein
the negative pressure generation mechanism includes a guide groove formed in a bottom of the negative pressure generation groove portion and extending from the leakage side toward the island-shaped land portion arranged in the negative pressure generation groove portion.
3. The sliding members according to claim 1 , wherein
the negative pressure generation mechanism includes a guide groove formed in a bottom of the negative pressure generation groove portion and extending from each of the leakage side and the sealed fluid side toward the island-shaped land portion arranged in the negative pressure generation mechanism.
4. The sliding members according to claim 1 , wherein
the negative pressure generation mechanism is arranged across an average diameter of the at least one of the sliding faces.
5. The sliding members according to claim 1 , wherein
the negative pressure generation mechanism further includes a fluid introduction groove portion having the opening end portion and extending in a radial direction, and
the negative pressure generation groove portion is a circumferentially extending groove portion which extends from the fluid introduction groove portion to the closed end portion in the circumferential direction.
6. The sliding members according to claim 5 , wherein
the one of the sliding faces further includes a positive pressure generation groove portion communicated with the fluid introduction groove portion at one end and circumferentially extending toward a downstream side of relative rotation of the sliding faces.
7. The sliding members according to claim 1 , wherein
at least another negative pressure generation mechanism is provided in at the at least one of the sliding faces.
8. The sliding members according to claim 1 , wherein
at least another island-shaped land portion is provided in the negative pressure generation mechanism.
9. The sliding members according to claim 2 , wherein
the negative pressure generation mechanism includes a guide groove formed in a bottom of the negative pressure generation groove portion and extending from each of the leakage side and the sealed fluid side toward the island-shaped land portion arranged in the negative pressure generation mechanism.
10. The sliding members according to claim 2 , wherein
the negative pressure generation mechanism is arranged across an average diameter of the at least one of the sliding faces.
11. The sliding members according to claim 2 , wherein
the negative pressure generation mechanism further includes a fluid introduction groove portion having the opening end portion and extending in a radial direction, and
the negative pressure generation groove portion is a circumferentially extending groove portion which extends from the fluid introduction groove portion to the closed end portion in the circumferential direction.
12. The sliding members according to claim 11 , wherein
the one of the sliding faces further includes a positive pressure generation groove portion communicated with the fluid introduction groove portion at one end and circumferentially extending toward a downstream side of relative rotation of the sliding faces.
13. The sliding members according to claim 2 , wherein
at least another negative pressure generation mechanism is provided in at the at least one of the sliding faces.
14. The sliding members according to claim 2 , wherein
at least another island-shaped land portion is provided in the negative pressure generation mechanism.
15. The sliding members according to claim 3 , wherein
the negative pressure generation mechanism is arranged across an average diameter of the at least one of the sliding faces.
16. The sliding members according to claim 3 , wherein
the negative pressure generation mechanism further includes a fluid introduction groove portion having the opening end portion and extending in a radial direction, and
the negative pressure generation groove portion is a circumferentially extending groove portion which extends from the fluid introduction groove portion to the closed end portion in the circumferential direction.
17. The sliding members according to claim 16 , wherein
the one of the sliding faces further includes a positive pressure generation groove portion communicated with the fluid introduction groove portion at one end and circumferentially extending toward a downstream side of relative rotation of the sliding faces.