JP2020071031A - Linear motor drive device and surface shape measuring device - Google Patents

Abstract

To provide a linear motor drive device and a surface shape measuring device which can suppress the yoking of a driven part that occurs when the driven part moves.SOLUTION: A linear motor 12, a driven part 40, a direct-acting guide 42 and a holder 116 are arranged along a straight line B that is parallel to the vertical direction orthogonal to the horizontal direction when the linear motor 12, the driven part 40, the direct-acting guide 42 and the holder 116 are viewed from a first direction.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a linear motor drive device and a surface profile measuring device, and more particularly to a linear motor drive device and a surface profile measuring device having a linear motor and a driven part driven by the linear motor.

  As a linear motor, for example, a linear motor disclosed in Patent Document 1 has a stator that is a bar-shaped magnet, and a coil member that is fitted to the stator and that moves linearly along the stator. And have children.

  Further, Patent Document 1 discloses a surface shape measuring apparatus in which a linear motor driving device is applied to a driving device of a detector. This linear motor drive device has a linear motor and a driven part to which a detector is attached and which is driven by the linear motor. The driven part is connected to a balance weight via a wire wound around a pulley, and a mover is fixed to the balance weight. Therefore, according to this linear motor drive device, the detector can be moved via the balance weight, the wire, and the driven part by linearly moving the mover along the stator. By applying the linear motor drive device as the drive device of the detector in this way, there is no wear part, low vibration drive is possible, a wide speed range can be taken, high rigidity, simple structure, Advantageous effects such as no rush can be obtained.

JP, 2004-297978, A

  However, in the linear motor drive device of Patent Document 1, the driven part may yaw when the driven part moves, and when the driven part yaws, the roughness measurement accuracy may be affected.

  The present invention has been made in view of such circumstances, and an object of the present invention is also to provide a linear motor drive device and a surface profile measuring device that can suppress yawing of a driven part that occurs when the driven part moves. And

  In order to achieve the object of the present invention, a linear motor driving device of the present invention includes a stator extending in a first direction along a horizontal direction in a main body of the device, and a stator fitted to the stator. A linear motor having a moving element that can move along the driven portion, a driven portion that is fixed to the moving element of the linear motor and has a sliding surface, and is arranged adjacent to the driven portion, and is in sliding contact with the sliding surface. The linear motor, the driven part, the linear guide and the holder are fixed to the driven part and to which the detector having the tracing stylus is attached. When viewed from above, the linear motor, the driven part, the linear guide and the holder are arranged along a straight line parallel to the second direction along the vertical direction orthogonal to the first direction.

  In one aspect of the present invention, it is preferable that a heat insulating member is interposed between the moving element and the driven portion.

  In one aspect of the present invention, it is preferable that the driven part is configured by a heat insulating member.

  In order to achieve the object of the present invention, a surface profile measuring device of the present invention is a surface profile measuring device comprising a linear motor driving device of the present invention, a detector attached to a holder of the linear motor driving device, A probe attached to the detector and displaceable in the second direction.

  According to the present invention, it is possible to suppress yawing of the driven part that occurs when the driven part moves.

1 is a perspective view of a surface roughness measuring device equipped with a linear motor driving device of an embodiment. Block diagram showing the configuration of the surface roughness measuring device shown in FIG. Front view showing the configuration of the linear motor drive device shown in FIG. Sectional drawing of the linear motor drive device which follows the AA line of FIG. 3 is an enlarged cross-sectional view of a main part of a linear motor that constitutes the linear motor drive device of FIG.

  Embodiments of a linear motor driving device and a surface shape measuring device according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is an overall perspective view of a surface roughness measuring device 100 in which a linear motor driving device 10 of the embodiment is applied to a driving device of a detector 112. FIG. 2 is a block diagram showing the configuration of the surface roughness measuring device 100 shown in FIG.

  The X-axis direction shown in FIG. 1 is the horizontal direction, which is the first direction of the present invention, and indicates the moving direction of the detector 112 moved by the linear motor driving device 10. The Y-axis direction refers to the horizontal direction orthogonal to the X-axis direction. The Z-axis direction is the vertical direction that is the second direction of the present invention, and refers to the vertical direction that is orthogonal to the X-axis direction and the Y-axis direction. The surface roughness measuring device 100 is an example of the surface shape measuring device of the present invention.

  As shown in FIG. 1, the surface roughness measuring device 100 includes a linear motor driving device 10, a measuring unit 102, a data processing device 104, an input device 106, a monitor 108, and the like. The measuring unit 102 has a detector 112 that measures the surface roughness of the work W of FIG. 2 placed on the upper surface of the measuring table 110. The detector 112 is a holder 116 (of the linear motor driving device 10). (See FIG. 1).

  A probe (also referred to as a stylus) 114 that can be displaced in the Z-axis direction (vertical direction) is attached to the end of the detector 112, and the amount of displacement of the probe 114 in the Z-axis direction is the detector. The voltage is converted into a voltage by a differential transformer (not shown) built in 112. Then, this voltage value is A / D converted by an A / D converter (not shown) and output to a CPU (central processing unit) 118 of the data processing device 104 in FIG.

  The data processing device 104 is configured by each arithmetic processing circuit including a CPU 118 and a memory 120 such as a ROM (Read Only Memory) or a RAM (Random Access Memory). A program stored in the memory 120 is executed by the CPU 118. As a result, the function of each unit of the data processing device 104 is realized, and the measurement data indicating the surface roughness of the work W is acquired. The measurement data is output to the monitor 108 by the roughness output means 122 of the data processing device 104 and displayed on the monitor 108.

  As shown in FIG. 1, the linear motor driving device 10 is attached to a column 124 that is erected on the measuring table 110 in the Z-axis direction. Then, according to an instruction from the CPU 118 of FIG. 2, a motor (not shown) for moving in the Z-axis direction is driven, so that the entire linear motor driving device 10 is moved in the Z-axis direction along the column 124. Further, the holder 116 is moved in the X-axis direction by driving the linear motor 12 (see FIG. 5) of the linear motor driving device 10 in accordance with an instruction from the CPU 118. As a result, the tracing stylus 114 is moved along with the detector 112 in the X-axis direction. The joystick 126 mounted on the front surface of the measuring table 110 can also manually operate the motor for moving in the Z-axis direction and the linear motor for moving in the X-axis direction.

  Next, the linear motor drive device 10 will be described.

  FIG. 3 is a front view showing the configuration of the linear motor drive device 10, and its main parts are shown as a cross-sectional view. FIG. 4 is an enlarged cross-sectional view taken along the line AA of FIG. FIG. 5 is an enlarged cross-sectional view of a main part of the linear motor 12 that constitutes the linear motor drive device 10.

  The linear motor drive device 10 includes a linear motor 12 mainly including a stator 14 and a mover 16, a housing 18 that is a main body of the device, and fixing fittings 20 and 20 that fix both ends of the stator 14 to the housing 18. And are equipped with. Although not shown, the linear motor drive device 10 has a cable bear (registered trademark) for supplying power to the mover 16, an encoder for detecting the moving direction position of the mover 16, and an encoder in addition to the above-described configuration. It has a scale and limit sensors that are provided near both ends of the stator 14 and that detect the end limits of the mover 16.

First, an example of the linear motor 12 will be described with reference to FIG.
The linear motor 12 is a so-called shaft type linear motor. The linear motor 12 has a stator 14 which is a linear rod-shaped shaft member on which a field magnet is formed, and a mover 16 which is an annular member having a coil member as a main part is fitted to the stator 14. It is configured by

  The stator 14 is made of a magnetizable material, for example, a Fe—Cr—Co type metal, and has a circular cross section. Further, the stator 14 is magnetized so as to have a uniform magnetic flux distribution, preferably a substantially rectangular shape, along the longitudinal direction thereof. As a result, the stator 14 is provided with a magnetizing portion for driving in which N poles and S poles are alternately arranged along the longitudinal direction with the same magnetic pole width P, and this constitutes a magnet for field magnetism. Has been done. The magnetic pole width P is set to 30 mm, for example. The stator 14 thus configured extends in the X-axis direction as shown in FIGS. 3 and 4.

  The coil member 30 of the mover 16 is composed of two sets of coil groups (a first set of coil groups and a second set of coil groups) each including three U-phase, V-phase, and W-phase coils. The first group of coils is composed of coils U1, V1, and W1 and is arranged in this order in the longitudinal direction of the stator 14. The second set of coil groups includes coils U2, V2, and W2, which are arranged in this order in the longitudinal direction of the stator 14. Each of these coils is formed to have a width of 1/3 of the magnetic pole width P.

  These coils forming the coil member 30 are fixed and integrated so that the outer peripheral surface thereof is coated with an adhesive. The coil member 30 is built in the hollow portion of the hollow rectangular parallelepiped moving element frame 32, and is integrally supported by the inner peripheral surface of the moving element frame 32.

  Bearings 34, 34 fitted to the stator 14 and slidable on the stator 14 are provided at both ends of the mover frame 32 in the horizontal direction. By the action of the bearing portions 34, 34, the mover 16 slides along the stator 14.

  According to this linear motor 12, when current is supplied to the coil member 30 of the mover 16 from the above-described cable bear, the interaction between the current flowing through the coil member 30 of the mover 16 and the magnetic flux of the stator 14 causes According to Fleming's left-hand rule, the mover 16 linearly moves along the stator 14 in the X-axis direction. The linear motor 12 of FIG. 5 is an example, and linear motors of other configurations can be applied to the linear motor drive device 10 of the present invention. An example of a linear motor having another configuration is one in which the stator 14 side is configured by the coil member 30 and the mover 16 side is configured by the drive magnetizing portion.

  As shown in FIGS. 3 and 4, the linear motor driving device 10 of the embodiment includes a driven portion 40, a linear motion guide 42, and a holder 116 in addition to the linear motor 12. Further, according to the linear motor drive device 10, when the linear motor 12, the driven portion 40, the linear guide 42, and the holder 116 are viewed from the X-axis direction in FIG. 4, they are on the straight line B parallel to the Z-axis direction. It is arranged along. The configuration of each member will be described below.

  The driven part 40 includes a moving element fixing member 44, a connecting block 46, and a holder mounting member 48, and the moving element fixing member 44, the connecting block 46, and the holder mounting member 48 are connected along the straight line B. It is set up.

  The mover fixing member 44 is formed in a plate shape and is fixed to the lower part of the mover 16 of the linear motor 12. In addition, in the linear motor drive device 10 of the embodiment, the mover fixing member 44 is fixed to the mover 16 via the heat insulating sheet 50, but the invention is not limited to this fixing structure, and the mover fixing member 44 is not limited thereto. May be a fixed structure directly connected to the mover 16.

  The connection block 46 is formed in a substantially rectangular parallelepiped shape and is fixed to the lower portion of the moving element fixing member 44. The mover fixing member 44 has lower surfaces 44A and 44A, and these lower surfaces 44A and 44A are configured as sliding surfaces having high flatness.

  The linear guide 42 is formed in a substantially rectangular parallelepiped shape and is arranged along the X-axis direction. A slit 42A (see FIG. 3) along the X-axis direction is formed through the linear guide 42 in the Z-axis direction, and a connecting block 46 is inserted and arranged in the slit 42A. Further, the linear guide 42 has side surfaces 42B, 42B (see FIG. 4) that define a slit 42A and have a vertical line in the Y-axis direction. Further, the linear guide 42 has upper surfaces 42C and 42C, and the upper surfaces 42C and 42C are configured as reference surfaces having high flatness that are in sliding contact with the lower surfaces 44A and 44A. Therefore, the driven portion 40 is moved in the X-axis direction with the lower surfaces 44A and 44A of the moving element fixing member 44 in sliding contact with the upper surfaces 42C and 42C of the linear guide 42, thereby achieving high accuracy in the X-axis direction. Be moved in.

  The holder mounting member 48 is formed in a substantially rectangular parallelepiped shape, and is connected to the lower portion of the connection block 46 by a plurality of screws 52, 52 ... Further, a dovetail groove 48A for mounting the holder 116 is provided in the lower portion of the holder mounting member 48, and the dovetail portion 116A of the holder 116 is engaged with the dovetail groove 48A so that the holder 116 is mounted on the holder mounting member 48. It is installed.

  The holder 116 is formed in a substantially rectangular parallelepiped shape and has an arcuate slit 116B formed along the X-axis direction. A detector 112 having a substantially cylindrical outer shape is fitted in the slit 116B, and the detector 112 is pressed against the inner peripheral surface of the slit 116B by a screw 54 screwed into the slit 116B from the outside of the holder 116. Fixed. At this time, the tracing stylus 114 is displaced in the Z-axis direction.

  The operation of the linear motor drive device 10 configured as described above will be described.

  The linear motor drive device 10 according to the embodiment is arranged along the straight line B parallel to the Z axis when the linear motor 12, the driven portion 40, the linear guide 42 and the holder 116 are viewed from the X axis direction in FIG. Since the driven portion 40 is arranged, it can move in the X-axis direction without yawing or in a state where yawing is suppressed.

  Here, the linear motor drive device 10 of the embodiment and the linear motor drive device of Patent Document 1 will be compared.

  In the linear motor drive device of Patent Document 1, when the linear motor and the driven portion are viewed from the direction of the movement axis of the driven portion (X-axis direction), the linear motor and the driven portion are relatively horizontal. It is arranged offset (in the Y-axis direction). For this reason, the driven part may be moved in a state where it receives a twisting moment from the wire, and therefore may yaw in the center of the Z axis during the movement. That is, when the driven part moves along the X-axis direction which is the moving direction, it may oscillate in the rotation direction about the Z-axis.

  On the other hand, as shown in FIG. 4, the linear motor drive device 10 of the embodiment includes the linear motor 12, the driven part 40, the linear guide 42, and the holder 42 in the direction of the movement axis of the driven part 40 (X-axis direction). When viewing 116, the linear motor 12, the driven portion 40, the linear guide 42, and the holder 116 are not relatively offset in the Y-axis direction, but along a straight line B parallel to the Z-axis. Are arranged. As a result, the driven portion 40 is guided by the linear motion guide mechanism by the lower surface 44A and the upper surface 42C without receiving the torsion moment from the linear motor 12 or in a state where the torsion moment is reduced. Move in the axial direction. Therefore, yawing of the driven part 40 that occurs when the driven part 40 moves can be suppressed.

  The linear motor 12, the driven part 40, the linear guide 42 and the holder 116 are arranged along the straight line B to mean that the linear motor 12, the driven part 40, the linear guide 42 and the holder 116 are arranged. It is the most preferable form to arrange the respective centers of gravity along the straight line B, but the present invention is not limited to this form, and the linear motor 12, the driven portion 40, the linear guide 42, and the holder 116 are respectively arranged. A part of them may be arranged on the straight line B in an overlapping state. As a result, the linear motor 12 is transmitted from the linear motor 12 to the driven portion 40 as compared with the configuration of Patent Document 1 in which the linear motor and the driven portion are relatively offset in the horizontal direction (Y-axis direction). It is possible to reduce the twisting moment. As an example, if the linear motor 12, the driven part 40, the linear motion guide 42, and the holder 116 are shaped symmetrically with respect to the straight line B, the linear motor 12, the driven part 40, the linear motion guide 42, and The center of gravity of each of the holders 116 can be arranged along the straight line B.

  Further, according to the linear motor drive device 10 of the embodiment, as shown in FIG. 4, the linear motor 12 is arranged at a position higher than the driven part 40 and the linear guide 42. As a result, most of the heat of the linear motor 12 generated by the supply (excitation) of the current is radiated upward from the upper portion of the linear motor 12, so that the heat of the linear motor 12 is driven by the driven portion 40 and the linear guide. It is possible to suppress the transmission to 42. With such an arrangement configuration of the linear motor 12, it is possible to suppress thermal deformation of the lower surface 44A that is a sliding surface and the upper surface 42C that is a reference surface, and thus suppress a dimensional error due to heat generation of the linear motor 12. be able to.

  Further, in order to more effectively block the heat transmitted from the linear motor 12 to the driven portion 40 and the linear guide 42, a heat insulating sheet 50 may be interposed between the moving element 16 and the moving element fixing member 44. preferable. Thereby, the dimensional error caused by the heat generation of the linear motor 12 can be suppressed more effectively. The heat insulating sheet 60 may be made of phenol resin or glass fiber.

  Further, without using the heat insulating sheet 60, at least a part (a part located on the linear motor 12 side) of the mover fixing member 44 or the connecting block 46 that configures the driven portion 40 may be formed of a heat insulating member. .. Examples of the above-mentioned heat insulating member include a fiber heat insulating material or a foam heat insulating material sandwiched between two metal plates (for example, aluminum plates). Furthermore, the driven part 40, which is a heat insulating member, and the heat insulating sheet 60 may be combined.

  Further, according to the surface roughness measuring device 100 having such a linear motor driving device 10, since the linear motor driving device 10 suppresses the yawing of the driven portion 40, the dimensional error due to the yawing is reduced. be able to.

  Further, in the embodiment, the surface roughness measuring device 100 is exemplified as the surface shape measuring device to which the linear motor driving device 10 is applied, but the probe of the detector is brought into contact with the object to be measured to obtain a perfect circle of the object to be measured. The linear motor driving device 10 may be applied to the driving device of the roundness measuring device that measures the degree.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above examples, and it is needless to say that various improvements and modifications may be made without departing from the scope of the present invention. ..

  For example, the stator of the present invention is arranged in the horizontal direction that is the first direction, but the horizontal direction does not have to be a completely horizontal direction. It may be arranged so as to be inclined in a direction inclined by a predetermined angle. In other words, it suffices that the mover in the non-excited state is arranged at an inclination angle that does not slide along the stator due to the frictional resistance between the mover and the stator. Along with this, the linear motor, the driven part, the linear guide and the holder of the present invention are arranged along the straight line B, but on the straight line orthogonal to the inclination angle of the stator. It may be arranged along.

  10 ... Linear motor drive device, 12 ... Linear motor, 14 ... Stator, 16 ... Mover, 18 ... Housing, 20 ... Fixing metal fitting, 30 ... Coil member, 32 ... Mover frame, 34 ... Bearing part, 40 ... Driven part, 42 ... Linear guide, 44 ... Moving member fixing member, 46 ... Connection block, 48 ... Holder mounting member, 50 ... Insulating sheet, 52 ... Screw, 54 ... Screw, 100 ... Surface roughness measuring device, 102 ... Measuring unit, 104 ... Data processing device, 106 ... Input device, 108 ... Monitor, 110 ... Measuring stand, 112 ... Detector, 114 ... Measuring element, 116 ... Holder, 118 ... CPU, 120 ... Memory, 122 ... Roughness Output means, 124 ... Column, 126 ... Joystick

Claims (4)

A linear motor having a stator extending in a first direction along the horizontal direction of the apparatus main body, and a slider fitted to the stator and movable along the stator,
A driven part having a sliding surface that is fixed to the mover of the linear motor;
A linear guide having a reference surface that is arranged adjacent to the driven portion and is in sliding contact with the sliding surface,
A holder fixed to the driven part, to which a detector having a probe is attached,
Equipped with
When the linear motor, the driven portion, the linear guide and the holder are viewed from the first direction, the linear motor, the driven portion, the linear guide and the holder are A linear motor drive device arranged along a straight line parallel to a second direction along a vertical direction orthogonal to the direction.   The linear motor drive device according to claim 1, wherein a heat insulating member is interposed between the mover and the driven part.   The linear motor drive device according to claim 1, wherein the driven portion is formed of a heat insulating member. A surface profile measuring device comprising the linear motor drive device according to claim 1.
A detector attached to the holder of the linear motor drive,
A probe attached to the detector and displaceable in a second direction;
A surface profile measuring device.

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