Sliding parts and processing method of sliding parts

• US 9,863,473 B2
• Filed: 02/23/2015
• Issued: 01/09/2018
• Est. Priority Date: 02/24/2014
• Status: Active Grant

• Current Assignee: Eagle Industry Company Limited
• Original Assignee: Eagle Industry Company Limited
• Inventors: Hosoe, Takeshi, Nishida, Shinji, Mori, Koichi, Negishi, Yuta, Kawai, Hideki, Itadani, Masatoshi
• Primary Examiner(s): Lee, Gilbert Y
• Application Number:
  US15/119,715
• Publication Number:
  US 20170067510A1
• Time in Patent Office: 1,051 Days
• CPC Class Codes: B23K 26/00 Working by laser beam, e.g. welding, cutting or boring
• CPC Class Codes: B23K 26/0624 using ultrashort pulses, i.e. pulses of 1ns or less
• CPC Class Codes: B23K 26/359 by providing a line or line pattern, e.g. a dotted break initiation line
• CPC Class Codes: B23K 26/364 for making a groove or trench, e.g. for scribing a break initiation groove
• CPC Class Codes: F16C 2220/60 by removing material, e.g. machining
• CPC Class Codes: F16C 2240/56 Tolerances; Accuracy of linear dimensions
• CPC Class Codes: F16C 33/043 Sliding surface consisting mainly of ceramics, cermets or hard carbon, e.g. diamond like carbon [DLC]
• CPC Class Codes: F16C 33/106 Details of distribution or circulation inside the bearings, e.g. details of the bearing surfaces to affect flow or pressure of the liquid
• CPC Class Codes: F16C 33/14 Special methods of manufacture; Running-in
• CPC Class Codes: F16C 33/741 by means of a fluid
• CPC Class Codes: F16J 15/34 with slip-ring pressed against a more or less radial face on one member
• CPC Class Codes: F16J 15/3412 with cavities F16J15/3424 takes precedence

Abstract

The present disclosure provides a processing method for preparing at least one sliding part of a pair of sliding parts, and includes a processing step of forming a shallow groove within a range of depth from 0.05 μm to 5 μm on a sealing face of the sliding part by irradiating an ultrashort pulse laser to a part of the sealing face where a positive pressure generation groove and a negative pressure generation groove are formed and removing part of a surface of the sealing face, wherein an energy fluence of the ultrashort pulse laser used in the processing step is 0.5 J/(cm²·pulse) to 7 J/(cm²·pulse).

Claims

1. A pair of sliding parts comprising sealing faces that relatively slide on each other, wherein:

a fluid circulation groove including an inlet section where a fluid comes in from a high pressure fluid side, an outlet section where the fluid goes out to the high pressure fluid side, and a communication section that provides communication between the inlet section and the outlet section is provided in the sealing face on one side;

the fluid circulation groove is isolated from a low pressure fluid side by a land section;

a positive pressure generation mechanism having a position pressure generation groove shallower than the fluid circulation groove is provided in a part surrounded by the fluid circulation groove and the high pressure fluid side;

the positive pressure generation groove communicates with the inlet section and is isolated from the outlet section and the high pressure fluid side by the land section;

the positive pressure generation groove is a shallow groove within a range of depth from 0.05 μ

m to 5 μ

m formed by irradiation of an ultrashort pulse laser;

and

a bulge due to debris at an edge of a processing part is less than 0.01 μ

m.

2. The sliding parts as set forth in claim 1, wherein:

a negative pressure generation mechanism including a negative pressure generation groove shallower than the fluid circulation groove is provided on an outside of the part of the sealing face on one side surrounded by the fluid circulation groove and the high pressure fluid side;

the negative pressure generation groove communicates with the inlet section and is isolated from the outlet section and the low pressure fluid side by the land section;

the negative pressure generation groove is a shallow groove within a range of depth from 0.05 μ

m to 5 μ

m formed by the irradiation of the ultrashort pulse laser;

and

a bulge due to debris at an edge of a processing part is less than 0.01 μ

m.

3. The sliding parts as set forth in claim 2, wherein a roughness Ra of a bottom face of the negative pressure generation groove is 1/10 or less of the laser processing depth.

4. The sliding parts as set forth in claim 1, wherein a roughness Ra of a bottom face of the positive pressure generation groove is 1/10 or less of the laser processing depth.

8. The sliding parts as set forth in claim 3, wherein a roughness Ra of a bottom face of the fluid communication passage/positive pressure generation groove is 1/10 or less of the laser processing depth.

5. A pair of sliding parts comprising sealing faces that relatively slide on each other, wherein:

a land section for generating dynamic pressure is provided to face a high pressure fluid side and a seal area is provided to face a low pressure fluid side in the sealing face on one side;

the land section and the seal area are arranged and separated from each other in a radial direction;

a part of the sealing face excluding the land section and the seal area is formed to be lower than faces of the land section and the seal area as a fluid communication passage/positive pressure generation groove;

the fluid communication passage/positive pressure generation groove is a shallow groove within a range of depth from 0.05 μ

m to 5 μ

m formed by irradiation of an ultrashort pulse laser;

and

a bulge due to debris at an edge of a processing part is less than 0.01 μ

m.

6. The sliding parts as set forth in claim 5, wherein:

a negative pressure generation mechanism including a negative pressure generation groove is provided on the high pressure fluid side of the seal area;

a downstream side of the negative pressure generation groove communicates with the fluid communication passage/positive pressure generation groove;

the negative pressure generation groove is a shallow groove within a range of depth from 0.05 μ

m to 5 μ

m formed by the irradiation of the ultrashort pulse laser;

and

a bulge due to debris at an edge of a processing part is less than 0.01 μ

m.

7. The sliding parts as set forth in claim 6, wherein a roughness Ra of a bottom face of the negative pressure generation groove is 1/10 or less of the laser processing depth.