JP2009083069A - Driver, working machine and measurement machine using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driver capable of performing positioning with high accuracy and a working machine and a measurement machine using the same. <P>SOLUTION: The driver is provided with: a guide rail 22; a slide plate 23 provided movably with respect to the guide rail 22; a linear motor 24 having a permanent magnet 25A provided in the guide rail 22 and a coil 26A provided in the slide plate 23; and a position detecting means 31 for detecting a position of the slide plate 23. The position detecting means includes a scale 32 extending along a moving direction of the slide plate 23 and a detection head 33 disposed so as to be opposed to the scale, with the detection head 33 directly fixed to the coil 26A, and the scale fixed to the guide rail 22. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a drive device, a processing machine using the same, and a measuring machine. Specifically, the present invention relates to a drive device using a linear motor as a drive source, and a processing machine and a measurement machine using the drive device.

  In precision processing machines such as machine tools, in recent years, processing accuracy of nanometers is required. Therefore, a feed mechanism using a linear motor and a linear scale (see, for example, Patent Document 1) and a feed mechanism using a feed screw and a linear scale have been proposed as a tool or workpiece feed mechanism.

  In the former feed mechanism, a feed base (grinding stone base) is movably supported by a stationary member via a hydrostatic bearing, a secondary side (magnet) of the linear motor is supported on the feed base, and a linear motor is supported on the fixed member. The primary side (coil) is arranged to face each other, the linear scale is arranged on the feed base, and the scale reading head is arranged on the fixed side member to face each other.

  As shown in FIG. 9, the latter feed mechanism is supported such that the table 1 is movably supported on the base 3 via the guide 2, and the feed screw shaft 4 is supported on the base 3 so as to be rotatable along the moving direction of the table 1. The nut member 5 that meshes with the feed screw shaft 4 is fixed to the table 1, the linear scale 6 is disposed on the guide 2, and the scale reading head 7 is disposed on the table 1 so as to face each other.

JP 2000-218529 A

In any of the feeding mechanisms described above, the linear scale mounting position is deviated with respect to the feeding shaft of the feeding mechanism, so that an error may occur depending on the work placement position.
For example, in the feeding mechanism shown in FIG. 9, when the workpiece W is placed on the left side or the right side of the table 1 with respect to the state where the workpiece W is placed on the center of the table 1, the posture of the table 1 is changed. Since it changes, a detection error may occur. As a result, the positioning accuracy of the table 1 is lowered, and there is a problem that high processing accuracy cannot be expected.

  An object of the present invention is to provide a driving device capable of positioning with high accuracy, and a processing machine and a measuring machine using the same.

  The drive device of the present invention includes a fixed member, a movable member provided to be movable with respect to the fixed member, a stator provided on the fixed member, and a linear motor having a mover provided on the movable member. And a position detecting means for detecting the position of the movable member with respect to the fixed member, wherein the position detecting means includes a scale extending along the moving direction of the movable member, and a detection disposed opposite to the scale. And one of the scale and the detection head is directly fixed to the movable element, and the other is fixed to the fixing member so as to face the one.

  According to this configuration, the position detection means includes a scale extending along the moving direction of the movable member, and a detection head disposed opposite to the scale, one of which is directly fixed to the mover, Since the other is fixed to the fixed member, that is, the scale and the detection head constituting the position detecting means are provided close to the stator and the movable member constituting the linear motor, the load related to the movable member Even if this is offset, the fluctuation of the clearance between the linear scale and the detection head can be reduced. Therefore, since detection errors can be reduced, highly accurate positioning can be realized.

Further, in the driving device of the present invention, one of the scale and the detection head fixed to the movable element is in the vicinity of a substantially central position in the width direction of the movable member orthogonal to the moving direction of the movable member, or It is preferable that the movable member including the movable element is disposed near the center of gravity of the movable member.
According to this configuration, one of the scale and the detection head is arranged in the vicinity of the substantially center position in the width direction of the movable member orthogonal to the moving direction of the movable member, or in the vicinity of the center of gravity position of the movable member including the mover. Therefore, even if the movable member is tilted in the width direction, the gap between the scale and the detection head does not change greatly, so that high accuracy can be maintained.

In the driving device of the present invention, the linear motor, a permanent magnet constituting a stator arranged on the fixed member along the moving direction of the movable member, and the movable member facing the permanent magnet. It is preferable that the moving head includes a coil constituting the movable element, and the detection head is fixed to the coil.
In that case, it is preferable that the coil is provided on the lower surface of the movable member, and the detection head is provided on the lower surface of the coil.
According to this configuration, the linear motor is composed of a permanent magnet and a coil, the coil is provided on the lower surface of the movable member, and the detection head is fixed to the lower surface of the coil. On the other hand, since the facing state of the scale and the detection head hardly fluctuates, high accuracy can be maintained.

In the drive device of the present invention, the linear motor includes a shaft having a magnet that constitutes a stator arranged on the fixed member along a moving direction of the movable member, and an outer periphery of the shaft on the movable member. Preferably, the scale is fixed to the outer peripheral surface of the shaft.
According to this configuration, since a so-called shaft motor composed of a shaft having a magnet and a coil surrounding the outer periphery is used, it can be arranged in the arrangement space of the conventional ball screw feed structure, and the mechanism design can be made. There is no need to make major changes. Moreover, since the scale is fixed to the outer peripheral surface of the shaft, the mounting can be simplified.

In addition, the processing machine and the measuring machine of the present invention are characterized by mounting any one of the above-described driving devices.
According to these processing machines and measuring machines, it is possible to provide a processing machine and a measuring machine that have all the effects of the drive device described above.
Here, the processing machine includes all processing machines that perform processing such as cutting, grinding, and cutting on the workpiece regardless of the material of the workpiece. Further, the measuring machine is meant to include all measuring machines that measure the dimensions and shape of the object to be measured.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
The first embodiment is an example in which the present invention is applied to a portal processing machine.
As shown in FIG. 1, the portal processing machine 10 of the first embodiment is constructed on a top surface of a base 11, a table 12 placed on the top surface of the base 11, and straddling the table 12. The gate-shaped frame 13, the Y-axis drive device 21Y that moves the gate-shaped frame 13 in the front-rear direction (Y-axis direction) on both sides of the table 12 in the width direction, and the portal-shaped frame 13 moves in the left-right direction (X-axis direction) X slider 16 provided so as to be able to move, X axis drive device 21X for moving X slider 16 in the X axis direction, and Z slider 17 provided on X slider 16 so as to be movable up and down (Z axis direction). And a Z-axis drive device 21Z that moves the Z-slider 17 up and down in the Z-axis direction, and a spindle 18 that is provided on the Z-slider 17 and attaches a processing tool 19 to the tip.
The portal frame 13 is formed in a portal shape from columns 14 disposed on both sides and a horizontal beam 15 spanned between the upper ends of the columns 14.

  2 and 3, the Y-axis drive device 21Y is provided so as to be movable via a guide rail 22 as a fixing member and a linear guide 29 relative to the guide rail 22, and the portal frame 13 on the upper surface. , A linear motor 24 that is provided between the guide rail 22 and the slide plate 23 and moves the slide plate 23 (gate frame 13), and a slide plate 23 for the guide rail 22 ( The position detecting means 31 detects the position of the portal frame 13).

The guide rail 22 is formed in a U-shaped cross section from a long bottom plate 22A having a constant width and a pair of side plates 22B erected on both sides of the bottom plate 22A in the width direction.
The slide plate 23 is constituted by a flat plate that supports the column 14 of the portal frame 13.
The linear motor 24 includes a stator 25 provided on the guide rail 22 and a mover 26 provided on the slide plate 23. The stator 25 is composed of a plurality of permanent magnets 25A attached at fixed pitches to the opposing inner surfaces of the pair of side plates 22B of the guide rail 22. The mover 26 is constituted by a coil 26A attached to the lower surface of the slide plate 23 while being sandwiched between permanent magnets 25A on both sides.

The position detecting means 31 includes an optical scale 32 extending along the moving direction of the slide plate 23 (gate frame 13), and a detection head 33 arranged to face the scale 32. The scale 32 is not limited to an optical scale, and may be a magnetic scale. However, since the optical scale is not affected by the magnetic force, it is preferable in terms of accuracy.
One of the scale 32 and the detection head 33 is directly fixed to the movable element 26, and the other is fixed to the guide rail 22 which is a fixing member so as to face the other. Here, the detection head 33 is directly fixed to the bottom surface side of the coil 26 </ b> A that is the movable element 26 at a substantially central position in the width direction of the slide plate 23 that is orthogonal to the moving direction of the movable element 26. The scale 32 is fixed to the center position of the inner surface of the bottom plate 22 </ b> A of the guide rail 22 with a predetermined gap and facing the coil 26 </ b> A.

The basic configuration of the X-axis drive device 21X and the Z-axis drive device 21Z is the same as that of the Y-axis drive device 21Y. However, the following points are different.
In the X-axis drive device 21X, a guide groove 27 is formed on the upper surface of the horizontal beam 15 along the X-axis direction, and a plurality of permanent magnets 25A as the stator 25 are formed on the inner surfaces (opposed inner surfaces) of the guide groove 27 facing each other. Is different from the Y-axis drive device 21Y in that the coil 26A as the mover 26 is provided on the lower surface of the X slider 16 via the slide plate 23 as a movable member.
In the Z-axis drive device 21Z, a guide groove 28 is formed along the Z-axis direction on the front surface of the X slider 16, and a plurality of permanent magnets 25A serving as a stator 25 are formed on the inner surface (opposite inner surface) of the guide groove 27 facing each other. Is different from the Y-axis drive device 21Y in that the coil 26A as the movable element 26 is provided on the back surface of the Z slider 17 via the slide plate 23 as a movable member.

  According to the first embodiment as described above, in the Y-axis drive device 21Y, the X-axis drive device 21X, and the Z-axis drive device 21Z, the position detection unit 31 includes the scale 32 that extends along the moving direction of the slide plate 23, and Since the detection head 33 is arranged to be opposed to the scale 32, the detection head 33 is directly fixed to the movable element 26, and the scale 32 is fixed to the guide rail 22 as a fixing member. That is, since the scale 32 and the detection head 33 constituting the position detecting means 31 are provided close to the stator 25 and the mover 26 constituting the linear motor 24, even if the load on the slide plate 23 is offset. The variation in the clearance between the scale 32 and the detection head 33 can be kept small. Therefore, since detection errors can be reduced, highly accurate positioning can be realized.

    The linear motor 24 includes a permanent magnet 25A constituting a stator 25 arranged on the guide rail 22 along the moving direction of the slide plate 23, and a mover arranged on the slide plate 23 facing the permanent magnet 25A. 26, the coil 26A is provided at the center of the slide plate 23 in the width direction of the lower surface, and the detection head 33 is provided on the lower surface of the coil 26A. Even with the change, since the facing state of the scale 32 and the detection head 33 hardly fluctuates, high accuracy can be maintained.

Second Embodiment
The second embodiment is an example in which the present invention is applied to a three-dimensional processing machine. In the description of the second embodiment, the same or corresponding components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted or simplified.

    As shown in FIG. 4, the three-dimensional processing machine 40 according to the second embodiment includes a base 41 having guide rails 41 </ b> A extending in the front-rear direction on both sides, and a table provided between the guide rails 41 </ b> A on both sides of the base 41. 42, a Y beam 43 stretched between the guide rails 41A on both sides, a Y axis drive device 21Y for moving the Y beam 43 in the front-rear direction (Y axis direction) along the guide rail 41A, and a Y beam 43 The X-slider 46 is provided so as to be movable in the left-right direction (X-axis direction), the X-axis drive device 21X that moves the X-slider 46 in the X-axis direction, and the X-slider 46 through the support block 46A in the vertical direction A Z slider 47 provided so as to be movable up and down (in the Z-axis direction), a Z-axis drive device 21Z that moves the Z slider 47 up and down in the Z-axis direction, The tip is provided via the door 47A mounting a machining tool 19 is constituted by a spindle 18.

The Y-axis drive device 21Y, the X-axis drive device 21X, and the Z-axis drive device 21Z of the second embodiment are the same as the Y-axis drive device 21Y, the X-axis drive device 21X, and the Z-axis drive device 21Z described in the first embodiment. Since the configuration is substantially the same, the description is omitted. However, the Y-axis drive device 21Y is different from the first embodiment in that the linear guide 29 is provided on the upper surface of the guide rail 41A on both sides of the base 41.
In the second embodiment, the same effect as that described in the first embodiment can be expected.

<Third Embodiment>
The third embodiment is an example in which the present invention is applied to a three-dimensional measuring machine. In the description of the third embodiment, components that are the same as or correspond to the components in each of the embodiments described above are given the same reference numerals, and descriptions thereof are omitted or simplified.

  As shown in FIG. 5, the three-dimensional measuring machine 50 according to the third embodiment moves in the front-rear direction (Y-axis direction) on both sides of the base 51, the table 52 installed on the base 51, and the base 51. A portal frame 53 having a column 54 and a horizontal beam 55 connecting between the upper ends of the columns 54, and the horizontal beam 55 of the portal frame 53 are provided to be movable in the left-right direction (X-axis direction). X slider 56, Z slider 57 provided on X slider 56 so as to be movable up and down (Z-axis direction), and spindle 58 provided rotatably on Z slider 57.

An object to be measured is placed on the upper surface of the table 52. A measurement probe 59 is replaceably attached to the lower end of the spindle 58.
The Y-axis drive device 21Y and the X-slider 56 for moving the portal frame 53 in the front-rear direction (Y-axis direction) and the Y-axis drive device 21X and the Z-slider 57 for moving the X-slider 56 in the left-right direction (X-axis direction) The Z-axis drive device 21Z moved in the direction) is configured by the first or second drive device (21Y, 21X, 21Z) described above.

According to the third embodiment, the portal frame 53 is driven in the Y-axis direction via the Y-axis drive device 21Y, the X slider 56 is driven in the X-axis direction via the X-axis drive device 21X, and the Z slider 57 is driven in the Z-axis direction. The measurement probe 59 is moved in the Z-axis direction via the device 21Z to bring the measurement probe 59 into contact with the measurement site of the object to be measured. Measurement is performed while the coordinate position of each axis at this time is read and positioned from the position detection means 31 incorporated in each of the driving devices 21Y, 21X, and 21Z.
According to the three-dimensional measuring machine of the present embodiment, since the drive device of the present invention is applied to the drive mechanisms 21Y, 21X, and 21Z of the respective axes, it is equivalent to the operations and effects described in the first and second embodiments. The effects and effects of can be achieved.

<Modification>
The present invention is not limited to the above-described embodiment, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
For example, in the first to third embodiments, an example in which a so-called driving device including a planar linear motor is used has been described, but the present invention is not limited thereto.

For example, a drive device including a linear motor 24 and position detecting means 31 as shown in FIG. 6 may be used. That is, the optical scale 32 and the detection head 33 constituting the position detection means 31 are different from the first to third embodiments in that the optical scale 32 and the detection head 33 are arranged in the vicinity of the center of gravity of the slide plate 23 including the coil 26A. .
Therefore, in the linear motor 24, the coil 26 </ b> A fixed to the slide plate 23 that is a movable member is formed in an inverted U shape, and the detection head 33 is disposed on the U-shaped inner bottom surface of the coil 26 </ b> A. A standing wall 22C is provided at the center of the guide rail 22, and an optical scale 32 is fixed to the tip of the standing wall 22C.

  According to such a configuration, the scale 32 and the detection head 33 constituting the position detection means 31 are arranged in the vicinity of the center of gravity position of the slide plate 23 including the coil 26 </ b> A of the linear motor 24. Even with respect to load fluctuations, fluctuations in the clearance between the scale 32 and the detection head 33 can be reduced, so that highly accurate detection can be guaranteed.

Moreover, the drive device provided with what is called a concentric linear motor 64 as shown in FIG.7 and FIG.8 may be sufficient. The concentric linear motor 64 includes a shaft 65 having a permanent magnet 65A constituting a stator arranged on a fixed member 62 along the moving direction of the movable member 63, and an outer periphery of the shaft 65 surrounded by the movable member 63. And a coil 66 </ b> A that constitutes the mover 66.
The position detection means 31 includes an optical scale 32 and a detection head 33, as in the first embodiment. One of the optical scale 32 and the detection head 33, here, the scale 32 is fixed along the axial direction at a position below the outer peripheral surface of the shaft 65, and the detection head 33 is directly on the inner surface of the coil 66A as a mover. It is fixed.

  According to such a configuration, the linear motor 64 includes the shaft 65 having the permanent magnet 65 </ b> A constituting the stator arranged on the fixed member 62 along the moving direction of the movable member 63, and the shaft 65 on the movable member 63. A coil 66A that surrounds the outer periphery and forms a mover, the scale 32 is fixed to the outer peripheral surface of the shaft 65, and the detection head 33 is fixed to the inner peripheral surface of the coil 66A. Since it is constituted by a so-called shaft motor, it can be arranged in the arrangement space of the conventional ball screw feed structure, and there is no need to greatly change the mechanism design. In addition, since the scale 32 is fixed to the outer peripheral surface of the shaft 65, there is an advantage that the mounting can be simplified.

  The present invention can be used not only for a driving device of a processing machine or a measuring machine, but also for a driving device such as an assembly device or a conveying device.

The perspective view which shows the portal processing machine concerning 1st Embodiment of this invention. The perspective view which shows the drive device of 1st Embodiment. III-III sectional view taken on the line of FIG. The perspective view which shows the three-dimensional processing machine concerning 2nd Embodiment of this invention. The front view which shows the three-dimensional measuring machine concerning 3rd Embodiment of this invention. The figure which shows the modification of the drive device of this invention. The perspective view which shows the further another modification of the drive device of this invention. VIII-VIII sectional view taken on the line of FIG. The figure which shows the conventional drive device.

Explanation of symbols

10 ... portal machine,
22 ... Guide rail (fixing member),
23 ... slide plate (movable member),
24 ... Linear motor,
25 ... Stator,
25A ... Permanent magnet,
26 ... Movers,
26A ... coil,
31 ... Position detecting means,
32 ... Scale,
33. Detection head,
40. Three-dimensional processing machine,
50. Three-dimensional measuring machine.

Claims (7)

A fixed member, a movable member provided movably with respect to the fixed member, a stator provided on the fixed member, a linear motor having a mover provided on the movable member, and the fixed member In a drive device comprising position detection means for detecting the position of the movable member,
The position detection means includes a scale extending along a moving direction of the movable member, and a detection head disposed to face the scale.
One of the scale and the detection head is directly fixed to the movable element, and the other is fixed to the fixing member so as to face the one. The drive device according to claim 1,
One of the scale and the detection head fixed to the mover is near the center position in the width direction of the movable member orthogonal to the moving direction of the movable member, or the center of gravity of the movable member including the mover A drive device characterized by being arranged in the vicinity of the position. The drive device according to claim 1 or 2,
The linear motor includes a permanent magnet constituting a stator arranged on the fixed member along a moving direction of the movable member, and a coil constituting a mover arranged on the movable member so as to face the permanent magnet. And comprising
The drive device, wherein the detection head is fixed to the coil. The drive device according to claim 3, wherein
The drive device according to claim 1, wherein the coil is provided on a lower surface of the movable member, and the detection head is provided on a lower surface of the coil. The drive device according to claim 1 or 2,
The linear motor includes a shaft having a magnet that constitutes a stator arranged along the moving direction of the movable member on the fixed member, and a movable member that is disposed around the outer periphery of the shaft. And a coil that includes
The drive device characterized in that the scale is fixed to the outer peripheral surface of the shaft.   A processing machine comprising the driving device according to claim 1.   A measuring machine on which the driving device according to claim 1 is mounted.

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