JP2015086970A - Sliding linear motion guide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sliding linear motion guide that suppresses increase of processing facility cost and in which sliding resistance is low at use even in a low sliding speed area where a supply amount of lubricant is less, a manufacturing method of the sliding linear motion guide, and a manufacturing deice of the sliding linear motion guide.SOLUTION: A sliding linear motion guide 1 includes: a stationary side guide rail 4 that has a sliding surface 2; and a movement side member 6 that includes a sliding surface 5 at a position opposite to the sliding surface 2, and is assembled into the guide rail 4 in a slidable manner. In the sliding linear motion guide, plural of fine recess parts with a substantially circular opening formed by irradiated both or one of the two sliding surfaces 2, 5 with pulse lase light of nanosecond order are provided at fixed intervals.

Description

  The present invention relates to a sliding linear guide used in a machine tool and the like, and an apparatus for manufacturing a sliding linear guide.

  Sliding linear motion guides used for machine tools and the like need to operate smoothly while supporting a large load. Conventionally, a resin having a low coefficient of friction was often used, but the resin was worn quickly and the replacement cycle was short. Also, when metal guides are used, the grooves that serve as oil reservoirs are formed by machining, so a relatively large number of grooves are provided, and it is difficult to hold a sufficient lubricating oil film. There were problems such as increased sliding resistance and seizure.

  In order to reduce the sliding resistance of the sliding linear guide or prevent seizure, it is necessary that a sufficient oil film is always formed on the sliding surface. Conventionally, scuffing performed for the purpose of securing the flatness and surface contact of the sliding surface is said to be effective in reducing the friction coefficient by the action of the oil sump, but it is a manual operation by a skilled worker. Therefore, it was difficult to improve production efficiency.

  For this reason, in order to form an oil film on the sliding surface, there has been proposed a sliding linear motion guide in which a structure serving as an oil reservoir is formed on the sliding surface. Further, a surface processing method for forming such a structure that becomes an oil reservoir has been proposed. For example, Patent Document 1 discloses that fine graphite particles are sprayed at a high speed on a sliding surface of a sliding linear guide, so that graphite deposited on the sliding surface is removed by so-called shot blasting, and a minute recess is formed on the sliding surface. Techniques for forming are described. Patent Document 2 describes a technique for forming a minute recess that becomes an oil reservoir on a sliding surface by shot peening.

JP 2011-69444 A JP 2010-133439 A

  However, in Patent Document 1, since minute concave portions are formed on the surface of the sliding surface by shot blasting, it is difficult to control the shape, size, and depth of the formed concave portions. In addition, since shot blasting requires a special processing step, the cost of processing equipment increases, and it is difficult to adopt it for mass-produced products from the viewpoint of cost. Similarly, in Patent Document 2, it is difficult to accurately control the size and arrangement of minute recesses by shot peening.

  The present invention has been made in view of such a situation. A sliding linear motion guide, a sliding guide, which suppresses an increase in processing equipment cost and has a low sliding resistance during use even when the amount of lubricant supplied is small. It is an object of the present invention to provide a method for manufacturing a linear motion guide and an apparatus for manufacturing a sliding linear motion guide.

  In order to solve the above-described problems, a sliding linear guide according to the present invention includes a stationary guide rail having a sliding surface, and a sliding surface at a position opposite to the sliding surface. A substantially linear opening formed by irradiating the two sliding surfaces with a pulsed laser beam in the order of nanoseconds. It is characterized in that a large number of minute recesses having a certain distance are provided.

  In a preferred aspect of the present invention, the recess has a diameter of the opening of 10 μm to 50 μm, a depth of 0.3 μm to 5.0 μm, and an interval between the adjacent recesses of 20 μm or more. It is provided with 500 micrometers or less.

  In a preferred aspect of the present invention, one of the concave portions is formed by irradiating one pulse of the nanosecond order pulse laser beam.

  The sliding linear guide manufacturing method according to the present invention includes a stationary guide rail having a sliding surface and a sliding surface at a position opposite to the sliding surface, and is slidable with respect to the guide rail. In the manufacturing method of the sliding linear motion guide comprising the moving side member assembled to the microscopic concave portion having a substantially circular opening by irradiating the two sliding surfaces with a pulsed laser beam of nanosecond order Including a step of forming a large number of particles at regular intervals.

  Also, a preferred aspect of the present invention is characterized in that one recess is formed by irradiating one pulse of the nanosecond order pulse laser beam.

  Further, the sliding linear motion guide manufacturing apparatus according to the present invention is a manufacturing apparatus for carrying out the above linear motion guide manufacturing method, the stage for placing the guide blank, and the nanosecond order. A laser oscillator that oscillates the pulse laser beam, a galvano scanner for deflecting and scanning the pulse laser beam output from the laser oscillator, and the pulse laser beam deflected by the galvano scanner in the blank of the guide And an fθ lens that emits light so as to move on the sliding surface at a constant speed.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the sliding linear guide which has small sliding resistance at the time of use also in the low sliding speed area where the supply amount of a lubricant is small while suppressing the increase in processing equipment costs, and the sliding linear guide The manufacturing apparatus can be provided.

1 is an overall view of a sliding linear motion guide device including a sliding linear motion guide according to the present embodiment. It is a general view of the sliding linear motion guide which concerns on this embodiment. It is an enlarged view of a sliding surface. It is an enlarged view of a recessed part. 1 is a schematic diagram illustrating a configuration of a laser beam machine according to an embodiment. It is a graph showing the pulse period of a laser. It is a schematic diagram which shows the processing state to the workpiece by a laser processing machine. (A) is a graph which shows distribution of the diameter of a recessed part, (b) is a graph which shows distribution of the depth dimension of a recessed part. 1 is an overall view of a sliding linear motion guide device including an inverted V-shaped sliding linear motion guide. It is drawing which shows the modification of this invention.

  Hereinafter, a sliding linear motion guide, a sliding linear motion guide manufacturing method, and a sliding linear motion guide manufacturing apparatus according to embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is an overall view of a sliding linear motion guide device 20 including a sliding linear motion guide 1 according to the present embodiment. The linear sliding guide device 20 is provided with one or two or more linear sliding guides 1, and usually one of them has a V-shaped section and a direction perpendicular to the moving direction of the guide. The other guides are flat and have only a function of bearing a load. The V-shape may be a V-shape as shown in FIG. 1 or an inverted V-shape as shown in FIG. 9, and each is selected as necessary.

  FIG. 2 is an overall view of the sliding linear motion guide 1 according to the present embodiment. The linear sliding guide 1 includes a stationary guide rail 4 having a sliding surface 2 and a sliding surface 5 at a position opposite to the sliding surface 2, and is slidably assembled to the guide rail 4. The moving side member 6 is configured. Usually, lubricating oil or a lubricant is disposed between the two sliding surfaces 2 and 5. The stationary guide rail 4 is attached to the frame of the apparatus, and the moving member 6 is attached to a tool spindle, a work spindle, etc., and moves on the stationary guide rail 4.

  FIG. 3 is an enlarged view of the sliding surface 2. In the sliding linear motion guide 1 according to the present embodiment, a large number of recesses 23 functioning as oil sumps are formed on the sliding surfaces 2 and 5. FIG. 4 is an enlarged view of the recess 23. Each concave portion 23 has a circular closed portion, and has an opening with a diameter of 10 μm to 50 μm and a depth of 0.3 μm to 5.0 μm. Moreover, the space | interval of the adjacent recessed part 23 and the recessed part 23 is formed in the fixed space | interval of 20.0 micrometers or more and 500.0 micrometers or less.

  A large number of the recesses 23 have an opening diameter of 10 μm or more and 50 μm or less, and an interval between the adjacent recesses 23 and the recesses 23 is formed at a constant interval of 20.0 μm or more and 500.0 μm or less. A puddle is formed. Further, if the depth of the recess 23 is less than 0.3 μm, there is a fear that the recess 23 may disappear due to initial wear. If the depth exceeds 5.0 μm, the lubricating oil accumulated in the recess 23 moves to a smooth surface. The ability to form an oil film is reduced. Therefore, it is preferable that the depth of the recess 23 is 0.3 μm or more even at the shallowest depth, and 5.0 μm or less even at the deepest depth.

  In addition, the recessed part 23 may be formed in both the sliding surface 2 of the fixed side guide rail 4 and the sliding surface 5 of the movement side member 6 like this embodiment, or the two sliding surfaces 2 and 5 may be formed. You may form in any one of these.

  By forming a large number of recesses 23 as described above that function as oil reservoirs on one or both of the sliding surfaces 2, 5, it is possible to increase the oil film parameter Λ and reduce the friction coefficient. By reducing the friction coefficient, it contributes to the reduction of sliding friction dominant in the low sliding speed range. The oil film parameter Λ is the ratio of the oil film thickness h to the surface roughness σ (Λ = h / σ). The larger the oil film parameter Λ is, the more oil film thickness is sufficient to reduce the sliding resistance. It means that there is h.

  Thus, the sliding linear motion guide 1 according to the present embodiment increases the oil film forming ability on the sliding surfaces 2 and 5 by forming a large number of the concave portions 23 as described above on the sliding surfaces 2 and 5. The sliding resistance during use can be reduced even in a low sliding speed range where the amount of lubricant supplied is small. Further, when a sufficient oil film is formed on the sliding surfaces 2 and 5, it is possible to prevent seizure.

  Next, the manufacturing method and manufacturing apparatus of the sliding linear motion guide 1 according to the present embodiment will be described. The manufacturing method of the sliding linear guide 1 which concerns on this embodiment is a manufacturing method including the process using the laser processing machine which is a manufacturing apparatus of the sliding linear guide demonstrated below.

  The recess 23 formed on one or both of the sliding surfaces 2 and 5 is formed by laser light irradiation by a laser processing machine. FIG. 5 is a schematic diagram showing the configuration of the laser beam machine 25 according to the present embodiment.

  The laser processing machine 25 is a laser marker that irradiates laser light having a pulse width of the order of nanoseconds. The laser processing machine 25 includes a laser oscillator 27 that oscillates a pulsed laser beam on the order of nanoseconds, a biaxial (X axis and Y axis, the same applies hereinafter) type galvano scanner 29, an fθ lens 31, a workpiece 33, that is, a slip. And a stage 35 for mounting and fixing the sliding surfaces 2 and 5 of the linear guide 1. The biaxial galvano scanner 29 includes a pair of galvanometer mirrors 37 and 37.

  The pulsed laser light of nanosecond order has a longer irradiation time per pulse and higher output than the pulsed laser light of picosecond order. Therefore, the processing logarithm 33 has a large amount that can be processed by one pulse of laser light irradiation. On the other hand, pulsed laser light of nanosecond order has a greater thermal influence on the workpiece 33 than processing by picosecond order laser light, so that the influence of heat is limited to use within a range where there is no problem in quality. .

  As shown in FIG. 5, the pulse laser beam in the order of nanoseconds output from the laser oscillator 27 is deflected and scanned by the galvanometer mirrors 37 and 37 of the biaxial galvano scanner 29 via the optical system 39, and is applied to the fθ lens 31. Incident. The biaxial galvano scanner 29 deflects the irradiation direction of the laser beam output from the laser oscillator 27 by moving the galvano mirrors 37 and 37 at an equal angular velocity, and scans the laser beam in a plane at an equal angle. The laser beam incident on the fθ lens 31 is applied to the workpiece 33. At this time, the fθ lens 31 converts the constant angular velocity motion of the laser light whose incident angle to the fθ lens 31 is changed by the galvano scanner 29 so as to scan the processing surface of the processing object 33 at a constant speed. In other words, the constant angular velocity motion of the laser light is converted into a constant velocity motion. Further, the fθ lens 31 suppresses fluctuations in the spot diameter of the laser light irradiated on the workpiece 33.

  In the present embodiment, one recess 23 is formed by irradiating one pulse of laser light. While deflecting the irradiation direction of the laser beam by the galvano scanner 29 and the fθ lens 31 so that the laser beam scans the processing surface of the workpiece 33 at a constant speed, the laser beam is irradiated on the order of nanoseconds at a predetermined period. . Then, one recess 23 is formed by one laser beam irradiation. By performing single pulse processing in this way, processing can be performed in a shorter time than multiple pulse processing in which a plurality of pulses are irradiated to form one recess 23.

  The stage 35 on which the workpiece 33 is placed can be fixed with the sliding surface 2 of the moving guide rail 4 or the sliding surface 5 of the moving member 6 facing upward. The stage 35 may be fixed, or the laser beam irradiation direction may be fixed and the stage 35 may be movable on two axes (X axis, Y axis). Furthermore, both the laser light irradiation direction and the stage 35 can be made movable so that the scanning speed of the laser light with respect to the workpiece 33 can be further increased and the processing time can be shortened.

FIG. 6 is a graph showing the pulse period of the laser beam, and FIG. It is a schematic diagram which shows a processing state. The distance α (mm) between the centers of the recesses 23 formed adjacent to each other depends on the scanning speed V (mm / S) of the laser beam and the repetition frequency f (Hz) or the pulse period T (sec). The relationship among the scanning speed V, the repetition frequency f, and the pulse period T is expressed by the following equation (1) or (2).
(1) α = V / f
(2) α = V × T

  Further, if laser light is irradiated during acceleration / deceleration of the galvano scanner 29, the interval between the processing positions of the formed recesses 23 changes. Therefore, laser light is not irradiated during acceleration / deceleration of the galvano scanner 29. By controlling the galvano scanner 29 and the laser oscillation rod 27 as described above, processing is performed in which the adjacent recesses 23 are spaced at a constant interval. Further, the depth of the formed recess 23 depends on the peak power of the laser beam, and the diameter of the opening of the recess 23 is equal to or smaller than the spot diameter of the laser beam.

  FIG. 8A is a graph showing the distribution of diameters of the recesses 23 formed using the laser processing machine 25, and FIG. 8B is a graph showing the distribution of depth dimensions. As shown in FIGS. 8A and 8B, the numerous recesses 23 formed using the laser processing machine 25 according to the present embodiment are distributed in a relatively narrow range in diameter and depth. It is formed in a stable and constant shape without variation.

Table 1 shows the relationship between the laser irradiation conditions when the recess 23 is formed using the laser processing machine 25 and the state of the formed recess 23. As shown in Table 1, when the laser beam is irradiated with three kinds of average outputs (6 W, 12 W, and 16 W), the depth of the recessed portion 23 to be formed varies depending on the output. Specifically, the laser beam was formed at an appropriate depth when irradiated with an average output of 16 W, deeper than an appropriate depth when irradiated with an average output of 20 W, and shallower than an appropriate depth when irradiated with an average output of 6 W. That is, if the output of the laser beam is large, the recess 23 is formed deep, and if the output is small, it is formed shallow. Thus, it can be seen that the depth of the recess 23 depends on the output level of the laser beam as described above. In addition, the diameter of the recessed part 23 to be formed is formed within an appropriate size range regardless of the size of the output.

  Thus, if the laser beam machine 25 according to the present embodiment is used, the size and depth of the recess 23 to be formed can be controlled by adjusting the output of the laser beam.

  As described above, according to the present invention, there is provided a sliding linear motion guide having a low sliding resistance in use even when the supply amount of lubricant or lubricant is small, a method for manufacturing the guide, and a device for manufacturing the guide. be able to. In addition, since the laser oscillator 27 that oscillates a laser beam in the order of nanoseconds is used for processing the recess 23, the processing equipment cost can be reduced as compared with the case of using a laser oscillator in the order of picoseconds, thereby improving productivity. be able to. Further, the size and depth of the formed recess 23 can be controlled by adjusting the output of the laser beam.

  In addition, this invention is not limited to the said embodiment, A change is possible suitably. For example, although the sliding surface 2 is formed on the stationary guide rail 4 in the above embodiment, a separate sliding member 8 is attached to the stationary guide rail 4 as shown in FIG. A concave portion 23 according to the present invention may be formed on the sliding surface 9. Similarly, a separate sliding member 10 may be attached to the moving member 6, and the recess 23 may be formed on the sliding surface 11 of the sliding member 10.

DESCRIPTION OF SYMBOLS 1 Sliding linear motion guide 2, 5 Sliding surface 4 Fixed side rail 6 Moving side member 9, 11 Sliding surface 8, 10 Sliding member 20 Sliding linear motion guide device 23 Recessed part 25 Laser processing machine 27 Laser oscillator 29 Galvano scanner 31 fθ lens 33 processing object 35 stage 37 galvanometer mirror 39 optical system

Claims (6)

  A sliding linear guide comprising: a fixed side guide rail having a sliding surface; and a moving side member provided with a sliding surface at a position opposite to the sliding surface and slidably assembled to the guide rail. A large number of minute recesses having a substantially circular opening formed by irradiating both or one of the two sliding surfaces with a pulsed laser beam on the order of nanoseconds are provided at regular intervals. Sliding linear guide characterized by being made.   The recess has a diameter of the opening of 10 μm to 50 μm, a depth of 0.3 μm to 5.0 μm, and an interval between adjacent recesses of 20 μm to 500 μm. The sliding linear motion guide according to claim 1, wherein the sliding linear motion guide is characterized in that:   The sliding linear motion guide according to claim 1 or 2, wherein one of the concave portions is formed by irradiating one pulse of the nanosecond-order pulse laser beam.   A sliding linear guide comprising: a fixed side guide rail having a sliding surface; and a moving side member provided with a sliding surface at a position opposite to the sliding surface and slidably assembled to the guide rail. In the manufacturing method, a step of forming a large number of minute recesses having substantially circular openings at a constant interval by irradiating both or one of the two sliding surfaces with a pulsed laser beam on the order of nanoseconds. A method of manufacturing a sliding linear guide characterized by comprising:   5. The method for manufacturing a sliding linear guide according to claim 4, wherein one of the concave portions is formed by irradiating one pulse of the pulsed laser light of the nanosecond order.   A guide manufacturing apparatus for carrying out the manufacturing method of the sliding linear guide according to claim 4 or 5, wherein a stage for mounting a sliding surface of the sliding linear guide, and the nanosecond order A laser oscillation rod that oscillates the pulse laser beam, a galvano scanner for deflecting and scanning the pulse laser beam output from the laser oscillator, and the pulse laser beam deflected by the galvano scanner on the sliding surface And an fθ lens that irradiates the lens so as to move at a constant speed.