JP2011069444A - Method for machining sliding member and sliding linear motion guide with sliding member manufactured by the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for structuring a fine recessed part at low cost on a sliding surface of a sliding linear motion guide of a machine tool. <P>SOLUTION: A liquid jet is made to collide with the surface of the sliding member made of graphite cast iron, and graphite particles deposited on the surface of the sliding member are selectively eliminated, thereby forming the recessed part on the surface of the sliding member. When the method of liquid jet collision is used as a method for forming the recessed part on the sliding surface, the recessed part functioning as an oil reservoir can be formed on the sliding surface of the sliding linear motion guide at low cost effectively. Moreover, the size and depth of the recessed part functioning as the oil reservoir can be adjusted by processing conditions of the liquid jet collision. Furthermore, by masking a part of the sliding surface, the recessed part functioning as the fine oil reservoir can be easily formed in an optional region on the sliding surface of the sliding linear motion guide of the machine tool. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for forming a fine recess in a sliding surface of a sliding linear guide used for a reciprocating machine tool, and the sliding of a machine tool used for cutting difficult-to-cut materials such as dies. This is a method used to form a fine recess at a low cost on the sliding surface of the linear motion guide.

  In order to achieve high efficiency and high efficiency of cutting, development of machine tools equipped with highly rigid and highly damped sliding linear motion guides is progressing. Conventionally, sliding linear motion guides used in machine tools have been scraped for the purpose of ensuring the flatness of the sliding surface and the area per surface.

  Further, scoring the sliding surface of the sliding linear guide of the machine tool is one of effective means for reducing the sliding friction coefficient of the sliding linear guide. It has also been pointed out that a recess of about 10 μm provided on the sliding surface by scraping works as an oil pool during sliding of the sliding linear motion guide, and is effective in reducing the sliding friction coefficient. As shown in Patent Documents 1 to 6, paying attention to the action of the dent due to the scrape provided on this sliding surface, the sliding surface is provided with a fine dent to reduce the sliding friction coefficient of the sliding linear motion guide. Numerous means are disclosed as prior art.

  However, screeding of sliding surfaces of sliding linear guides used in machine tools is often performed manually by skilled engineers, and the area of sliding surfaces of machine tools is large, so the production of machine tools It was a bottleneck for improving efficiency.

  On the other hand, new technologies such as lithography processing, laser processing, and microblasting have spread as processing methods for forming regular fine surface patterning on the sliding surfaces of machine parts, and have attracted attention as an alternative to scoring processing. It has become. However, each of the surface patterning methods requires a special processing technique, and has a problem of increasing the cost. There is an increasing demand for a processing method for providing a fine recess on a sliding surface with high efficiency and low cost.

JP 2008-95808 A Japanese Patent No. 2724706 JP-A-62-218532 Japanese Patent Laying-Open No. 2005-22015 JP 2006-123151 A JP 2007-301696 A

Tokuji Umehara, Improvement of friction function by surface texture of machine parts, Journal of the Japan Society of Mechanical Engineers, 112-1086 (2009), pp.406-409 Hidemi Sugawara, New Technology for Applying Solid Lubricant to Piston Sliding Part and its Effect, HONDA R & D Technical Reviews, 14-1 (2002), pp. 85-91 Kenji Takeuchi, Naomi Yamaguchi, Akiko Hirayama, Noriaki Hishida, Hiroshi Yabe, Basic characteristics of sliding bearings for small equipment with moS2 shot processing (3rd report), Tribology conference proceedings, (2004-11), pp. 505- 506 Wang, X., Kato, K., Adachi, K and Aizawa, K., Loads Carrying Capacity map for the Surface Texture Design of SiC Thrust Bearing Sliding in Water, Tribology International, 36 (2003), pp. 189-197 Kazutake UEHARA, Fumio OBATA, Daijiro KONISHI and masato YAmASAKI, Frictional Characteristics of machine Tool's Slide Guides with micro-grooves and Cavities, Proceedings of the 4th International Conference on Leading Edge manufacturing in 21st Century, pp. 791-794

  The present invention provides a method for forming a fine recess at low cost on a sliding surface of a sliding linear motion guide of a machine tool.

  In order to solve the above-mentioned problem, the invention according to claim 1 of the present invention is to selectively cause graphite particles deposited on the surface of the sliding member by causing a liquid jet to collide with the surface of the sliding member made of graphite cast iron. By removing, a concave portion is formed on the surface of the sliding member.

  The invention according to claim 2 selects the graphite particles deposited on the surface of the sliding member by mechanically polishing the surface of the sliding member made of graphite cast iron, then causing a liquid jet to collide with the surface of the sliding member. In this method, the concave portion is formed on the surface of the sliding member by removing the surface of the sliding member.

  According to a third aspect of the present invention, a liquid jet is made to collide with the surface of a sliding member made of graphite cast iron, and the graphite particles deposited on the surface of the sliding member are selectively removed to thereby form the surface of the sliding member. A method of processing a sliding member, comprising forming a recess and then mechanically polishing the surface of the sliding member.

  A fourth aspect of the present invention is the sliding member processing method according to any one of the first to third aspects, wherein a water flow is used as the liquid jet.

  A fifth aspect of the present invention is a sliding linear guide characterized by including a sliding member manufactured by the processing method according to any one of the first to fourth aspects.

  If the method of the present invention called liquid jet collision is used as a method for forming a concave portion on the sliding surface of a machine tool, a concave portion that functions as an oil sump etc. is efficiently formed on the sliding surface of the sliding linear guide at low cost. can do. Moreover, it is possible to adjust the size and depth of the recess functioning as an oil sump depending on the processing conditions of the liquid jet collision. Further, if a part of the sliding surface is masked, it is easy to form a recess functioning as a fine oil sump in an arbitrary region of the sliding surface of the sliding linear motion guide of the machine tool.

It is a figure which shows the outline of the water jet processing method which concerns on Example 1 of this invention. It is a figure which shows the path | route of the nozzle of the water jet processing machine which concerns on Example 1 of this invention. It is a figure which shows the cross-sectional shape of the sliding face after making a water jet collide with the sliding face 4 of this invention. It is a figure which shows the cross-sectional shape of the sliding face after making a water jet collide with the sliding face 4 of this invention. It is a figure which shows the cross-sectional shape of the sliding face after making a water jet collide with the sliding face 4 of this invention. It is a figure which shows the cross-sectional shape of the sliding face after making a water jet collide with the sliding face 4 of this invention. It is a figure which shows the outline of the water jet processing method which concerns on Example 2 of this invention. It is a figure which shows the path | route of the nozzle of the water jet processing machine which concerns on Example 2 of this invention. It is a figure which shows the cross-sectional shape by a confocal laser microscope and the sliding surface observation result before and behind the water jet process of the test piece A of this invention. It is a figure which shows the cross-sectional shape by a confocal laser microscope and the sliding surface observation result before and behind the water jet process of the test piece B of this invention. It is a figure which shows the cross-sectional shape by a confocal laser microscope and the sliding surface observation result before and behind the water jet process of the test piece C of this invention. It is a figure which shows schematic structure of a sliding friction test. It is a figure which shows the sliding friction coefficient of the sliding linear guide model which has a sliding surface which concerns on Example 2 of this invention.

  Hereinafter, a method for forming a minute recess on a sliding surface using the method according to the present invention and a configuration example of a sliding linear motion guide provided with a sliding member manufactured by the method will be described in detail with reference to the accompanying drawings. Explained.

  FIG. 1 is a diagram showing a processing method according to an embodiment of the present invention. In the present embodiment, a water jet processing machine (not shown) is used for jetting the liquid, and the water flow from the nozzle 1 of the water jet processing machine installed opposite to the grinding sliding surface 4 as shown in FIG. Processing was performed by spraying 2. In this embodiment, the liquid jet was a water flow and was ejected from a single-hole nozzle 1 (hole inner diameter 0.25 mm) for cutting. Four types of water pressure were ejected from the nozzles: 49, 98, 74, and 147 MPa. The distance between the nozzle 1 and the sliding surface 4 (nozzle offset amount) was 50 mm, and the nozzle was moved at a feed speed of 2000 mm / min along the nozzle operation path 8 shown in FIG. The offset, nozzle feed speed, water pressure, nozzle hole diameter, and nozzle angle are not limited to these. 6 represents a vise (vise), and the test piece was fixed on the table of a water jet machine.

  3 to 6 show the surface of four spheroidal graphite cast iron (FCD600) test pieces 3 that have been ground and irradiated with a water jet by a water jet machine, and the cross-sectional shape of each test piece surface by a confocal laser microscope is shown. The measurement results are shown. By irradiating the ground sliding surface 4 with a water jet at a water pressure of 147 MPa, recesses 7 having a diameter and a depth of about 100 μm and about 30 μm were formed on the grinding sliding surface 4, respectively. Further, as the water pressure of the water jet increased, the diameter and depth of the recess formed in the grinding sliding surface 4 increased.

FIG. 7 is a diagram showing a processing method according to one embodiment of the present invention. As in the case of Example 1, in this example, a water jet processing machine was used for liquid injection. As shown in FIG. 7, the water flow 2 was jetted from the nozzle 1 of a water jet processing machine installed facing the polishing sliding surface 5 for processing. The liquid jet was a water flow, and was ejected from a single-hole nozzle 1 (hole inner diameter 0.25 mm) for cutting. The water pressure injected from the nozzle was three types of 49, 98, and 147 MPa. The distance between the nozzle 1 and the polishing sliding surface 5 (nozzle offset amount) was 50 mm. FIG. 8 shows an operation path 8 of the nozzle of the water jet processing machine. The nozzle was moved at a feeding speed of 2000 mm / min at intervals of 0.5 mm pitch, and the jet flow was made to collide with the entire sliding surface. The test piece was fixed on the table of a water jet processing machine with a vice 6. The offset, nozzle feed speed, water pressure, nozzle hole diameter, and nozzle angle are not limited to these.

  In this example, a test piece made of spheroidal graphite cast iron (FCD600) was used, and a 20 mm square sliding linear motion guide model was used. The surface irradiated with a water jet by a water jet machine was mirror finished by polishing. Table 1 shows the conditions when water jet machining was performed on FCD600 test pieces. Test pieces A to C are water-jet processed test pieces on the sliding surfaces subjected to polishing mirror surface processing under the conditions shown in Table 1. For comparison, a sliding friction test using an FCD600 slider (test piece D in Table 1) subjected only to polishing mirror surface processing was also performed.

  FIGS. 9 to 11 show three mirror-finished spheroidal graphite cast iron (FCD600) specimens before and after water jet machining (a on the left side of each figure is before machining and b on the right side of each figure is after machining). The observation result of the surface of each test piece and the result of measuring the cross-sectional shape with a confocal laser microscope are shown. In this experiment, in order to investigate the influence of water jet processing on the removal state of carbon particles, the cross-sectional shape is the same graphite particle (the left side of each figure is P before processing, and the right side of each figure is P ′ after processing). Measured focusing on By removing the graphite phase, a fine dent (depth of about 25 μm) was formed as an oil reservoir.

  The processing method according to claim 2 shown in the present embodiment is a method in which a liquid jet is made to collide after mechanical polishing of the sliding surface, but the surface roughness of the region other than the concave portion on the surface of the sliding member is reduced. When it is necessary to make it, a recessed part can also be formed in the sliding member surface by the method of Claim 3. That is, first, a liquid jet is made to collide with the surface of the sliding member to form a recess on the surface of the sliding member, and the surface of the sliding member is mechanically polished to such an extent that the recess remains. The surface roughness of the region can be reduced.

  An embodiment of the sliding linear motion guide according to claim 5 of the present invention will be described. The result of having measured the sliding friction coefficient using the spheroidal graphite cast iron (FCD600) test piece manufactured with the processing method of Claim 2 shown in Example 2 is shown.

  FIG. 12 shows a schematic diagram of a testing machine (Tribogear Type 14 FW manufactured by Shinto Kagaku Co., Ltd.) used in the sliding friction test. In this testing machine, the spheroidal graphite cast iron (FCD600) slider manufactured by the processing method according to claim 2 is unidirectionally loaded on a high hardness mirror surface plate made of alloy tool steel (SKD11) with a vertical load of 39.2 N. The sliding friction force at that time was detected by a load cell. The vertical load was given by the weight installed on the upper part of the slider. Further, the size of the contact surface between the slider and the plate was 20 mm × 20 mm, and the contact surface pressure was 0.098 MPa. Table 2 shows the test conditions of this sliding friction test. The measurement result of the sliding friction coefficient is shown in FIG. The measurement of the coefficient of friction was repeated 3 to 20 times under the same conditions.

  FIG. 13 shows the influence of the jet water flow pressure on the sliding friction coefficient of the slider sliding surface made of FCD600. The sliding friction coefficient varied greatly with the water pressure of the water flow. This suggests that the sliding friction coefficient can be controlled by appropriately selecting the water pressure of the water flow.

According to the present invention, a fine oil sump can be provided at low cost and high efficiency on a sliding surface of a sliding linear motion guide of a machine tool.

DESCRIPTION OF SYMBOLS 1 Nozzle of water jet processing machine 2 Water flow 3 Test piece 4 Grinding sliding surface 5 Polishing sliding surface 6 Vise 7 Recess 8 Operation path

Claims (5)

  A liquid jet is made to collide with the surface of a sliding member made of graphite cast iron, and a recess is formed on the surface of the sliding member by selectively removing graphite particles deposited on the surface of the sliding member. Processing method of sliding member.   The surface of the sliding member made of graphite cast iron is mechanically polished, and then a liquid jet is made to collide with the surface of the sliding member to selectively remove the graphite particles deposited on the surface of the sliding member, thereby A method for processing a sliding member, wherein a concave portion is formed on the surface of the moving member.   A liquid jet is made to collide with the surface of the sliding member made of graphite cast iron to selectively remove the graphite particles deposited on the surface of the sliding member, thereby forming a recess on the surface of the sliding member, and then the sliding A method for processing a sliding member, wherein the member surface is mechanically polished.   The method for processing a sliding member according to any one of claims 1 to 3, wherein a water flow is used as the liquid jet.   A sliding linear motion guide comprising a sliding member manufactured by the processing method according to any one of claims 1 to 4.