JP2007313622A - Slide guide unit of machine tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a capacity of a motor which makes a moving body move in a slide guide for guiding the feed of the moving body of a machine tool. <P>SOLUTION: A slide guide surface 50 guiding the moving body 14 is formed on the upper surface of a bed 10, a plurality of air jets 55 are formed on the sliding surface 54 of the moving body which slides the slide guide surface, and air is jetted from the jet 55 to the slide guide surface. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sliding guide device for a machine tool, and more particularly to a sliding guide device used for guiding a moving body such as a tailstock in a precision roll lathe for machining a groove on an outer peripheral surface of a roll.

  A machine tool for processing a roll includes a roll grinder and a roll lathe. The roll grinding machine includes a spindle stock, a tailstock, and a carriage, and a grinding wheel is provided on the carriage.

  Conventionally, in a roll grinding machine, a groove is machined on the outer circumferential surface in addition to grinding the outer circumferential surface of the roll with a grindstone. Patent Document 1 describes a roll grinding machine in which a groove processing device having a cutting saw blade for cutting a groove is provided on a carriage.

  A roll lathe is a lathe in which a tool post with a diamond tool is installed on a carriage. The basic usage is to process the circumferential groove while rotating the roll on the headstock and feeding the carriage back and forth (X axis). When machining the groove in the axial direction, the groove can be created in the axial direction by moving the carriage in the left-right direction (Z-axis) at high speed while indexing the roll on the headstock (C-axis).

  In recent years, with the advance of machine control technology, ultra-precision machining with a lathe has been realized. As a result, a mold for molding an optical lens can be processed even on a lathe. For example, the present applicant has proposed a vertical lathe for processing a mold for forming a Fresnel lens (Patent Document 2). This vertical lathe can process the V-shaped lens groove of the Fresnel lens molding die with high accuracy.

  By the way, with the widespread use of liquid crystal display devices, the demand for lens sheets used for backlights of liquid crystal panels is increasing. In addition to the Fresnel lens described above, this type of lens sheet includes a lenticular lens sheet, a cross lenticular lens sheet, and a prism sheet.

Recently, it has been studied to form a lenticular lens sheet, a cross lenticular lens sheet, and a prism sheet using a roll-shaped mold with an extruder.
JP 2003-94239 A JP 2004-358624 A

  When processing these lens sheet molding dies with a roll lathe, it is necessary to precisely process circumferential grooves (vertical grooves) and longitudinal grooves (lateral grooves) on the outer peripheral surface of the roll. There are the following problems.

  In the longitudinal groove processing, as described above, while turning the roll at high speed on the headstock, the diamond bite is sent in the radial direction to turn the groove, so it is good under the necessary and sufficient cutting speed by the high-speed rotation of the roll. A smooth surface can be obtained.

  On the other hand, in the processing of the lateral groove, the roll is indexed by the headstock and then processed while feeding the carriage in the longitudinal direction. However, in order to process at a sufficient cutting speed, the feed rate must be increased. For this reason, rolling guidance is used for guidance of the saddle on which the carriage is mounted.

  On the other hand, the tailstock is moved at the time of taking out the finished roll or adjusting the support position according to the length of the roll in the setup work, but unlike the carriage, it moves at high speed. Since there is no need to do this, sliding guidance is used for the guidance. However, in order to process the groove in the roll with high accuracy, it is necessary to use a fine and heavy tailstock, and a large capacity motor is required to move the tailstock.

  Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art, and in a sliding guide for guiding the feeding of the moving body of a machine tool, the motor for moving the moving body can have a small capacity, Another object of the present invention is to provide a sliding guide device for a machine tool suitable for guiding a tailstock on a roll lathe for machining grooves.

  In order to achieve the above object, the present invention provides a sliding guide device for guiding a linear motion of a moving body such as a table on a bed of a machine tool, wherein a sliding guide surface for guiding the moving body is provided on an upper surface of the bed. And a plurality of air outlets are formed on the sliding surface of the moving body that slides on the sliding guide surface, and air is jetted from the outlet toward the sliding guide surface. .

  According to the present invention, during the movement of the moving body, the moving body floats slightly from the sliding guide surface due to the ejection of air. Therefore, even if the moving body is heavy, Due to the cooperation between the support and the support by the oil film, the load on the sliding guide surface is reduced, and even a motor with a small capacity can be moved.

Hereinafter, an embodiment of a sliding guide cooling device for a machine tool according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a side view of a precision roll lathe to which the present invention is applied, and FIG. 2 is a plan view of the precision roll lathe.
1 and 2, reference numeral 10 indicates a bed. On the bed 10, a spindle stock 12, a tailstock 14, and a carriage 16 are arranged. The workpiece is a roll-shaped workpiece W and is rotatably supported by the headstock 12 and the tailstock 14.
The headstock 12 is disposed at one end of the bed 10 in the longitudinal direction. The headstock 12 includes a main body portion 17, a main shaft 18, a chuck 19 attached to the tip of the main shaft 18, and a servo motor 20 that drives the main shaft 18. The main shaft 18 is supported by a hydrostatic bearing (not shown) built in the main body portion 17. The chuck 19 grips the axis of the workpiece W and transmits the rotation of the main shaft 19 to the workpiece. In the headstock 12, the servo motor 20 drives the main shaft 18 in order to rotate the workpiece W at a high speed. In addition, the encoder 22 detects the amount of rotation of the servo motor 20 and controls the amount of rotation of the servo motor 20, whereby an indexing shaft for indexing the workpiece W in the circumferential direction is controlled. A function as a C axis) is added. In addition to the hydrostatic bearing, the bearing of the headstock 12 may be an air bearing or a bearing bearing.

  Next, the tailstock 14 is disposed on the bed 10 so as to face the headstock 12. A guide rail 50 (see FIG. 4) is provided on the upper surface of the bed 10, and the tailstock 14 is installed so as to be movable by being guided by the guide rail 50. The tailstock 14 includes a main shaft 23 instead of a conventional general tailstock shaft, and a shaft of the workpiece W is rotatably supported by a chuck 25 attached to the main shaft 23. Such a tailstock 14 has the same basic configuration as the headstock 12 except that it does not have a servo motor.

Next, the carriage 16 will be described.
The carriage 16 includes a saddle 26 installed on the bed 10 so as to be movable in the axial direction of the workpiece W. A table 28 is installed on the saddle 26 so as to be movable in a direction perpendicular to the axial direction of the workpiece W. In the precision roll lathe according to this embodiment, the axis for feeding the saddle 26 is the Z axis, and the axis for feeding the table 28 on the saddle 26 is the X axis. In this precision roll lathe, in addition to the X-axis and Z-axis, the spindle table 12 is provided with the C-axis, and the cutter swivel table 30 provided on the table 28 is provided with the B-axis. It is a machine.

  FIG. 3 shows the cutter swivel 30. The cutter swivel 30 according to the present embodiment includes a swivel base body 31 and a top plate 32. On the top plate 32, a tool post 33 to which a plurality of cutting tools are attached and a fly cutter spindle device 34 are attached.

  A built-in servo motor constituting a B-axis for indexing an arbitrary bite of the tool post 33 or a fly cutter of the fly cutter spindle device 34 is incorporated in the swivel base body 31. The shaft that supports the top plate 32 is driven by this servo motor, and the top plate 32 can be turned.

  A tool post 33 is attached to one side of the top plate 32, and a fly cutter spindle device 34 is disposed at a position close to the other side. In this case, the fly cutter spindle device 34 is supported by a bracket 60 fixed to the tool post 33. The tool post 33 is a substantially semi-cylindrical tool post, and diamond tools 36 are arranged at predetermined intervals in the circumferential direction. In this embodiment, three diamond tools 36 can be determined by turning the tool post 33 every 90 degrees together with the top plate 32. However, four diamond tools 36 are turned every 60 degrees. There are various forms such as indexing. A counterweight 37 for balancing the weight of the fly cutter spindle device 34 is installed on the upper surface of the tool post 33.

  Next, the fly cutter spindle device 34 will be described. The fly cutter spindle device 34 includes a main body 34a, a servo motor 35, and a cutter holder 38 to which a fly cutter 39 is attached. Inside the main body 34a, a cutter spindle (not shown) is supported by an air bearing, and this cutter spindle is directly driven by a servo motor 35 and rotates at a high speed. The cutter holder 38 attached to the tip of the cutter spindle is a disc-shaped cutter holder in order to increase the peripheral speed. One fly cutter 39 made of a diamond tool is held on the outer periphery of the cutter holder 38. In this case, the cutter spindle device 34 supports the cutter spindle in a posture perpendicular to both the X-axis direction and the Z-axis direction, and rotates the fly cutter 39 at high speed in the XZ plane. The cutting edge of the diamond tool 36 attached to the tool post 33 is in the same plane as the XZ plane on which the fly cutter 39 rotates.

  In FIG. 3, an X-axis guide rail 40 having an inverted V-shaped guide surface is extended on the upper surface of the saddle 26, and a large number of rollers held by a retainer are arranged on the X-axis guide rail 40. A finite type rolling guide 41 is provided. Similarly, a Z-axis guide rail 42 having a guide surface formed in an inverted V shape extends on the upper surface of the bed 10, and a finite rolling guide 43 is provided on the Z-axis guide rail 42.

  In FIG. 4, a cooling jacket 44 extending along the Z-axis guide rail 42 is formed inside the bed 10. On the other hand, the bottom surface of the saddle 26 is formed with a V-groove 45 that forms a roller rolling surface on which the finite rolling guide 43 rolls. The bed 10 is a cast product made of gray cast steel.

Both the Z-axis feed driving device that sends the saddle 26 and the X-axis feed driving device that sends the table 28 on which the blade swivel 30 is mounted are composed of linear motors. In FIG. 3, reference numeral 47 indicates a permanent magnet array constituting a linear motor of the X-axis feed mechanism, and 48 indicates a permanent magnet array extending in parallel with the Z-axis guide rail 42.
As shown in FIG. 4, a guide rail 50 for guiding the tailstock 14 is provided on the upper surface of the bed 10 in parallel with the Z axis, and a sliding guide surface is formed on the upper surface of the guide rail 50. Yes. In the present embodiment, the following gear mechanism and guide mechanism are used to move the tailstock 14. That is, the rack 51 is attached to the side surface of the bed 10 in the longitudinal direction. A pinion 52 is engaged with the rack 51, and the pinion 52 is driven by a servo motor 53.

  A long groove 54 that fits into the guide rail 50 is formed at the bottom of the tailstock 14, and one surface forming the long groove 54 is a sliding surface 54a. A plurality of air outlets 55 are opened on the sliding surface 54 a of the long groove 54. In this embodiment, air pockets 59 are formed concentrically outside the jet port 54. These jet openings 55 are arranged so as to be separated from each other. And these jet outlets 55 make the air passage 56 common, and air ejects.

  In FIG. 5, reference numeral 57 indicates an oil groove formed on the surface of the sliding surface 54 a, and the oil groove 57 slides while being bent at a right angle so as to meander around the air outlet 55. It extends on the surface 54a. Lubricating oil is supplied to the oil groove 57.

The precision roll lathe to which the slip guide device according to the present embodiment is applied is configured as described above. Next, its operation and effect will be described.
First, the function of the cutter swivel 30 mounted on the carriage 16 of the precision roll lathe of this embodiment will be described.

  By properly using the tool post 33 and the fly cutter spindle device 34 installed on the tool swivel base 30 as follows, a vertical groove (groove in the circumferential direction) can be cut with respect to the workpiece W as well as a horizontal groove (axis) High-precision processing can also be performed on the direction grooves).

  The processing of the longitudinal groove is the same as that of a normal roll lathe. That is, of the diamond tool 36 of the tool post 33, the tool to be used is indexed by the B axis. Further, the workpiece W is rotated by the servo motor 20 of the head stock 12. Then, the table 28 can be fed in the X-axis direction, cut into the workpiece W with the diamond cutting tool 36, and the longitudinal groove can be turned.

  On the other hand, when machining the lateral groove, the fly cutter spindle device 34 is indexed by the B axis. And the position of the circumferential direction which should process the horizontal groove of the workpiece | work W with the C axis | shaft of the head stock 12 is calculated | required.

  As shown in FIG. 6, the servo motor 35 of the fly cutter spindle device 34 is activated, the cutter holder 38 is rotated at a high speed, and the fly cutter 39 is cut in the X-axis direction. Then, the lateral groove 52 is cut while feeding the fly cutter 39 along the Z axis. As a result, the fly cutter 39 intermittently cuts the workpiece W to create the lateral groove 52. Since the cutter holder 38 of the fly cutter spindle device 34 rotates at high speed, an ideal cutting speed (about 300 m / min) can be given to the fly cutter 39.

  In addition, the precision roll lathe according to the present embodiment can perform conventional planar processing without using the fly cutter spindle device 34. That is, it is possible to index the diamond cutting tool 36 of the tool post 33 and cut the lateral groove in the workpiece W while feeding the carriage 16 at high speed in the Z axis.

  According to the precision roll lathe of this embodiment, not only high-precision processing of horizontal grooves, but also high-precision processing of vertical grooves can be performed, so that it is possible to perform roll processing such as processing vertical grooves and horizontal grooves vertically and horizontally on the same roll. Become. For example, various lens sheet forming mold processing such as a mold for forming a cross lenticular lens sheet and a mold for forming a prism sheet can be realized.

After the grooves are machined vertically and horizontally in the above manner, the work for exchanging the workpiece W is performed. In this work exchange, the tailstock 14 needs to be moved.
The tailstock 14 is moved by driving a pinion gear 52 meshing with the rack 51 by a servo motor 53 in FIG. When the tailstock 14 moves, air is ejected from the ejection port 55 toward the guide rail 50. At this time, an oil film is formed between the sliding guide surface of the guide rail 50 and the sliding surface 54 a of the tailstock 14 by the lubricating oil supplied from the oil groove 57. While the tailstock 14 moves, the tailstock 14 floats slightly from the sliding guide surface due to the ejection of air. The area where the pressure acts is expanded by the air pocket 59. Therefore, even for the heavy tailstock 14 (1 ton), the sliding guide is provided by the cooperation of the air support and the oil film support. The load on the surface is reduced, and the tailstock 14 can be moved using the motor 53 having a small capacity. In particular, as in the present embodiment, it is necessary to use a precise and heavy tailstock with high motion accuracy in order to process a longitudinal groove and a lateral groove on a roll with high precision. The merit that can reduce the capacity of this motor is great.
Since the oil groove 57 meanders so as to avoid the air outlet 55, the supply of the lubricating oil from the oil groove 57 is hindered by the air jetted from the outlet 55. Rather, since an appropriate amount is diffused, weight reduction by floating and securing of oil film formation by the oil groove 50 are compatible.

The side view of the precision roll lathe to which this invention is applied. The top view of the precision roll lathe. The perspective view of the same knife swivel. The partial cross section front view which shows the cross section of the guide mechanism of the tailstock of the precision roll lathe. The figure which shows the arrangement | sequence of the air ejection opening opened to the sliding surface of a tailstock. Explanatory drawing of the lateral groove processing to the roll by a precision roll lathe.

Explanation of symbols

10 bed 12 spindle stock 14 tailstock 16 reciprocating carriage 19 chuck 20 servo motor 26 saddle 28 table 30 blade turntable 33 tool post 34 fly cutter spindle device 55 jet outlet 57 oil groove

Claims (4)

In a sliding guide device that guides the linear motion of a moving body such as a table on the bed of a machine tool,
A sliding guide surface for guiding the moving body is provided on the upper surface of the bed, and a plurality of air outlets are formed on the sliding surface of the moving body that slides on the sliding guide surface. A sliding guide device for machine tools, characterized in that air is ejected toward the machine.   2. A sliding guide device for a machine tool according to claim 1, wherein an oil groove meandering so as to avoid the air outlet is formed on the sliding surface of the movable body.   The machine tool is a headstock installed on a bed, while rotating a roll-shaped workpiece, machining a circumferential groove with a cutting tool swivel tool installed on the saddle, or the circumferential direction of the workpiece 2. The machine tool according to claim 1, wherein the roll is a roll lathe that processes an axial groove while performing indexing, and the moving body is a tailstock that supports a workpiece together with the headstock. Sliding guide device.   The slide guide device for a machine tool according to claim 3, wherein the tailstock has a main shaft to which a chuck for holding one end of a work is attached instead of the tailstock.

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