WO2022113694A1

WO2022113694A1 - Rotary table device

Info

Publication number: WO2022113694A1
Application number: PCT/JP2021/040725
Authority: WO
Inventors: 拓明下吉; 公介戸張
Original assignee: 日本トムソン株式会社
Priority date: 2020-11-26
Filing date: 2021-11-05
Publication date: 2022-06-02
Also published as: JP6856814B1; CN116097554A; JP2022084203A; KR20230038785A; TW202222014A

Abstract

This rotary table device comprises: a foundation part; a bearing mounted to the foundation part; a table rotatably supported on the foundation part with the bearing therebetween; and motors for rotating the table with respect to the foundation part toward the rotation direction of the bearing. The table has a table groove part that is annularly formed in the outer circumferential surface along the entire circumference and is recessed in the radial direction of the bearing. The foundation part has an annular coil base that is inserted in the table groove part and is disposed along the table groove part. The motors include a first motor and a second motor. The first motor includes, on a wall surface of the table defining the table groove part, a first magnet array which is an array of a plurality of magnets arrayed along the rotation direction of the bearing, and includes, on a first surface of the coil base, a first coil array which is an array of a plurality of coils arrayed so as to face the first magnet array. The second motor includes, on the wall surface of the table defining the table groove part, a second magnet array which is an array of a plurality of magnets arrayed along the rotation direction of the bearing, and includes, in the axial direction of the bearing and on a second surface of the coil base opposite to the first surface, a second coil array which is an array of a plurality of coils arrayed so as to face the second magnet array.

Description

Rotating table device

The present invention relates to a rotary table device. This application claims priority based on Japanese Patent Application No. 2020-195910 filed on November 26, 2020, and incorporates all the contents described in the Japanese patent application.

A rotary table device including a bed as a fixed portion, a rotary table as a rotary portion, and a bearing arranged between them is known. This rotary table device includes a direct drive servomotor in which a coil and a magnet are arranged in parallel with each other in the rotational direction, and is known to be driven by the direct drive servomotor (see, for example, Patent Document 1). ).

Japanese Unexamined Patent Publication No. 2005-333763

It may be desired that the rotary table device can exert a larger torque. At the same time, it is desired to be compact. Therefore, one of the objects of the present invention is to provide a compact rotary table device capable of exerting a large torque.

The rotary table device according to the present disclosure includes a base portion, a bearing installed on the base portion, a table rotatably supported with respect to the base portion via the bearing, and the base portion. A motor for rotating the table in the rotation direction of the bearing is provided with respect to the portion. On the table, a table groove portion recessed in the radial direction of the bearing is formed in an annular shape on the outer peripheral surface over the entire circumference. The base portion includes an annular coil base that enters the table groove portion and is arranged along the table groove portion. The motor includes a first motor and a second motor. The first motor has a first magnet row, which is a row of magnets arranged along the rotation direction of the bearing, on the wall surface of the table defining the groove portion of the table, and a first surface of the coil base. A first coil row, which is a row of coils arranged so as to face the first magnet row, is included. The second motor has a second magnet row, which is a row of magnets arranged along the rotation direction of the bearing on the wall surface of the table defining the groove portion of the table, and the second motor in the axial direction of the bearing. A second coil row, which is a row of coils arranged so as to face the second magnet row, is included on the second surface of the coil base located on the opposite side of the surface.

According to the rotary table device, a compact rotary table device that can exert a large torque is provided.

FIG. 1 is a perspective view showing a rotary table device according to the first embodiment. FIG. 2 is a cross-sectional view showing the rotary table device according to the first embodiment. FIG. 3 is a perspective view showing a table of the rotary table device according to the first embodiment. FIG. 4 is a side view showing a table of the rotary table device according to the first embodiment. FIG. 5A is a cross-sectional view showing the table according to the first embodiment. FIG. 5B is a cross-sectional view showing the table and bearings according to the first embodiment. FIG. 6 is a perspective view showing a second member of the table according to the first embodiment. FIG. 7 is a plan view showing the second member and the second magnet row of the table according to the first embodiment. FIG. 8 is a perspective view showing the first member of the table according to the first embodiment. FIG. 9 is a perspective view showing the first member and the first magnet row of the table in the first embodiment. FIG. 10 is a perspective view showing the coil base according to the first embodiment. FIG. 11 is a cross-sectional perspective view showing the coil base according to the first embodiment. FIG. 12 is a perspective view showing the coil base and the substrate according to the first embodiment. FIG. 13 is a perspective view showing the substrate and the coil according to the first embodiment. FIG. 14 is a perspective view showing the substrate and the coil according to the first embodiment. FIG. 15 is a plan view showing the rotary table device according to the first embodiment. FIG. 16 is a schematic diagram showing an electrical connection of the rotary table device according to the first embodiment.

[Outline of Embodiment]
First, embodiments of the present disclosure will be listed and described. The rotary table device according to the present disclosure includes a base portion, a bearing installed on the base portion, a table rotatably supported with respect to the base portion via the bearing, and the base portion. A motor for rotating the table in the rotation direction of the bearing is provided with respect to the portion. On the table, a table groove portion recessed in the radial direction of the bearing is formed in an annular shape on the outer peripheral surface over the entire circumference. The base portion includes an annular coil base that enters the table groove portion and is arranged along the table groove portion. The motor includes a first motor and a second motor. The first motor has a first magnet row, which is a row of magnets arranged along the rotation direction of the bearing, on the wall surface of the table defining the groove portion of the table, and a first surface of the coil base. A first coil row, which is a row of coils arranged so as to face the first magnet row, is included. The second motor has a second magnet row, which is a row of magnets arranged along the rotation direction of the bearing on the wall surface of the table defining the groove portion of the table, and the second motor in the axial direction of the bearing. A second coil row, which is a row of coils arranged so as to face the second magnet row, is included on the second surface of the coil base located on the opposite side of the surface.

Conventionally, a rotary table device that is driven by a direct drive servomotor and positions a work in a predetermined position is known. Such a rotary table device is often used for the purpose of attaching a work or the like of other parts to the table and rotating the work. The angle of rotation is set to, for example, 60 °. There is also a rotary table device configured to rotate 360 °. For the purpose of rotating the work, it is preferable that the driving force of the rotary table device is large so that the rotating operation can be reliably performed even when the attached work is large and heavy. On the other hand, in consideration of replacement with the conventional device and compatibility with other parts, it is desirable that the rotary table device is compact and has dimensions that are not significantly different from the conventional device.

When trying to improve the driving force of the motor, it is conceivable to change the specifications of the coils and magnets that make up the motor. However, it may be desired to improve the driving force without changing the coil or magnet. In response to this need, the idea was to stack the motors in two stages in the direction of the rotation axis of the rotary table device. According to this configuration, it has been found that the driving force of the linear motor can be improved without changing the coil or magnet and without changing the radial and circumferential dimensions of the rotary table device. As a result of further studies, it was found that the arrangement of the motors stacked in two stages has the following configuration. That is, in the table provided in the rotary table device, a table groove portion recessed in the radial direction of the bearing is formed over the entire circumference of the outer peripheral surface of the table. In addition, the coil base on which the coil is placed should be placed so as to enter the table groove and follow the table groove. Further, the coils are arranged on both sides of the coil base.

According to this configuration, two motors can be arranged without changing the radial and circumferential dimensions of the rotary table as compared with the rotary table device equipped with a conventional motor (one-stage motor). In addition, it is possible to suppress an increase in dimensions in the axial direction while stacking the motors in two stages. Therefore, a rotary table device having a compact configuration and capable of obtaining driving force from two motors is provided.

In the rotary table device, a first recess in which the first coil row is arranged is formed on the first surface of the coil base, and a second coil row is arranged on the second surface of the coil base. It can be assumed that a recess is formed. According to this configuration, it is possible to further suppress the axial dimension of the rotary table device, and a more compact rotary table device can be obtained.

In the rotary table device, the wall surface of the table defining the table groove portion may include a first wall surface facing the first surface of the coil base and a second wall surface facing the second surface of the coil base. The first wall surface may have a first table wall surface portion that is a recess, and the first magnet row may be arranged in the first table wall surface portion. The second wall surface may have a second table wall surface portion that is a recess, and the second magnet row may be arranged in the second table wall surface portion. According to this configuration, the axial dimension of the rotary table device can be further suppressed, and a more compact rotary table device can be obtained.

In the rotary table device, the table includes a first member including a plate-shaped portion and a second member including a plate-shaped portion stacked axially with respect to the first member. It can be. Further, the bearing is a cross roller bearing, and the outer ring of the cross roller bearing may be sandwiched between the first member and the second member. According to this configuration, the housing of the bearing is formed by the first member and the second member, and the outer ring of the bearing can be directly sandwiched and held by the first member and the second member. This configuration facilitates machining and assembly of the turntable device. In addition, the bearing can be reliably held and used for rotational operation without losing the driving force of the motor.

In the rotary table device, the bearing and the coil base can be assumed to have the same center position in the axial direction of the bearing. The fact that the center position of the bearing and the coil base in the axial direction are the same means that the bearing and the coil base are arranged at the same height when viewed in the horizontal direction. The rotary table device of the present disclosure is provided with motors on both sides of the coil base, and the sum of the torques of the two motors is the driving force of the rotary table device. It is preferable that the coil base and the bearing are arranged at the same height because the driving force of the rotary table device is transmitted to the bearing without generating an eccentric load.

In the rotary table device, a first substrate fixed to the coil base is further provided between the first coil row and the first magnet row, and the coil base is provided between the second coil row and the second magnet row. The second coil row may be further fixed to the first substrate, and the second coil row may be fixed to the second substrate. By arranging the substrate between the coil and the magnet, the distance between the coil and the magnet can be maintained. In addition, the substrate can cover the upper surface of the recess of the coil base in which the coil is housed. With this configuration, it is possible to prevent dust and the like from entering the recess.

The rotary table device further includes a drive circuit and a control circuit for controlling the drive circuit, and the first motor and the second motor are electrically controlled in parallel with the drive circuit. It can be. According to this configuration, the first motor and the second motor are controlled by one drive circuit, and the first motor and the second motor operate simultaneously based on one signal (current). Therefore, the sum of the torques generated by the two motors can be effectively used without causing a deviation in the operation of the two motors.

[Specific example of embodiment]
Next, an example of a specific embodiment of the rotary table of the present disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are given the same reference number and the explanation is not repeated.

(Embodiment 1)
FIG. 1 is a schematic perspective view showing the structure of the rotary table device according to the first embodiment. In FIG. 1, the Z-axis direction is the direction in which the rotation axis (rotation axis of the bearing) R of the table of the rotary table device extends. FIG. 2 is a schematic cross-sectional view showing the structure of the rotary table device, and shows a state cut by AA in FIG. FIG. 15 is a schematic plan view showing the structure of the rotary table device.

First, a schematic configuration of the rotary table device 1 will be described.
With reference to FIG. 1, the rotary table device 1 according to the first embodiment includes a base portion 10 which is a fixed portion, and a table 20 which is rotatable with respect to the base portion 10. The base portion 10 is supported by the bed 40, which is a support base, the columns 41 (41a to 41d) provided at the four corners of the bed, and the columns 41a to 41d, and is fixed to the bed 40 via the columns 41a to 41d. The coil base 50 is included. The columns 41a to 41d are at the same height as each other, and the coil base 50 is provided horizontally. With reference to FIG. 2, in the rotary table device 1 according to the first embodiment, the base portion 10 and the table 20 are connected to each other via a bearing 30. The bearing 30 is installed on the base portion 10. The inner ring 31 of the bearing 30 is fixed to the base portion 10, and the outer ring 32 of the bearing 30 is fixed to the table 20.

The outline of the fixed structure of the inner ring 31 of the bearing 30 will be described with reference to FIGS. 1, 2, and 15. In addition to the above-described configuration, the base portion 10 has a cylindrical first central portion 42 rising from the bed 40 along a circular hole in the center of the bed 40, and a second central portion continuous above the first central portion 42. 43 and. The bed 40 and the first central portion 42 are fixed by screws 45. The first central portion 42 and the second central portion 43 are fixed by screws 46. The first central portion 42 is a roughly cylindrical member, but the outer periphery of the upper portion thereof is a recess, and when combined with the lower surface of the second central portion 43, the housing of the inner ring 31 of the bearing 30 is configured. do. That is, the inner ring 31 of the bearing 30 is sandwiched and fixed by the first central portion 42 and the second central portion 43. The bearing 30 is a cross roller bearing provided with rollers 33. In the bearing 30, a seal 34 is provided between the inner ring 31 and the outer ring 32. The fixed structure of the outer ring 32 of the bearing 30 will be described later.

With reference to FIGS. 1, 2, and 15, an upper shutter 91 extending in an annular shape is arranged above the bearing 30. The upper shutter 91 covers the gap between the inner ring 31 and the outer ring 32 above the bearing 30. The upper shutter 91 is fixed to the second central portion 43 with a screw 48. A lower shutter 92 extending in an annular shape is arranged below the bearing 30. The lower shutter 92 covers the gap between the inner ring 31 and the outer ring 32 at the bottom of the bearing 30. The lower shutter 92 is fixed to the bed 40 with screws 44. The upper portion of the lower shutter 92 is formed on a slope that inclines downward from the upper end of the lower shutter 92 toward the center. By forming the lower shutter 92 in this shape, even when the lubricant leaks from the bearing 30 and the lubricant is received by the lower shutter 92, it is possible to prevent the lubricant from invading the motor or other parts. The upper shutter 91 and the lower shutter 92 may be made of resin or steel. If the bearing 30 has a seal 34, the

shutters

91 and 92 can be deleted. Further, when the

shutters

91 and 92 are present, the seal 34 of the bearing 30 can be deleted. Further, both the seal 34 and the

shutters

91 and 92 can be removed.

With reference to FIG. 2, the table 20 is formed with a table groove portion 60 which is a recess recessed inward from the outer circumference in the radial direction of the bearing 30 (XY direction in FIG. 2) over the entire circumference of the outer circumference. There is. The coil base 50 enters the table groove portion 60 and is arranged along the table groove portion 60. The coil 101 is arranged on the first surface 50a of the coil base 50. The magnet 201 is arranged on the wall surface 20a of the table 20 so as to face the coil 101. Further, the coil 301 is arranged on the second surface 50b of the coil base 50. A magnet 401 is arranged on the wall surface 20b of the table 20 so as to face the coil 301.

The magnet 201 forms a part of the first magnet row 200, which is a row of magnets arranged side by side in the rotation direction of the bearing 30. The coil 101 forms a part of the first coil row 100, which is a row of coils arranged in parallel so as to face the first magnet row 200. The first coil row 100 and the first magnet row 200 constitute the first motor 150. Further, the magnet 401 forms a part of the second magnet row 400, which is a row of magnets arranged side by side in the rotation direction of the bearing 30. The coil 301 forms a part of the second coil row 300, which is a row of coils arranged so as to face the second magnet row 400. The second coil row 300 and the second magnet row 400 constitute the second motor 350. That is, the rotary table device 1 includes two motors, a first motor 150 and a second motor 350.

Next, the table 20 of the rotary table device 1 will be described in more detail.
FIG. 3 is a perspective view showing the table 20 taken out. FIG. 4 is a side view of the table 20. FIG. 5A is a cross-sectional view of the table 20. FIG. 5B is a cross-sectional view showing the table 20 and the bearing 30 taken out.

With reference to FIGS. 3 and 4, in the table 20, the first member 21 and the second member 22 are stacked in the axial direction (Z direction) of the rotary table device. The first member 21 includes a first annular portion 23 which is roughly an annular plate shape, and a first tubular portion 24 which is a cylindrical portion extending downward from the inner circumference of the first annular portion 23 in the axial direction. ,including. The second member 22 includes a second annular portion 25 which is roughly in the shape of an annular plate, and a second tubular portion 26 which is a cylindrical portion that rises from the inner circumference of the second annular portion 25 and extends in the axial direction. ,including. The end face of the first cylinder portion 24 and the end face of the second cylinder portion 26 are in contact with each other. The first member 21 is formed with a screw hole 27a that penetrates the first annular portion 23 and the first tubular portion 24. In the first embodiment, 16 screw holes 27a are formed at equal intervals in the circumferential direction. Further, a screw hole 27b (FIG. 6) corresponding to the screw hole 27a is formed on the end surface of the second cylinder portion 26 of the second member 22 in contact with the first cylinder portion 24. The first member 21 and the second member 22 are fixed by inserting and fastening the screws over the screw holes 27a and 27b. A fixing hole 730 for fixing the position scale is provided on the outer periphery of the second annular portion 25 of the second member 22.

With reference to FIGS. 4 and 5, the outer diameters of the first cylinder portion 24 and the second cylinder portion 26 are equal to each other. That is, the outer peripheral surface of the first cylinder portion 24 and the outer peripheral surface of the second cylinder portion 26 are flush with each other. The table groove portion 60 is formed by the difference between the outer diameters of the first annular portion 23 and the second annular portion 25 and the outer diameters of the first tubular portion 24 and the second tubular portion 26. The outer peripheral surface of the first cylinder portion 24 and the outer peripheral surface of the second cylinder portion 26 form an inner peripheral wall surface 60c that defines the table groove portion 60. The wall surface 20a (FIG. 2) on the side of the first annular portion 23 of the first member 21 facing the coil base 50 constitutes the first wall surface 60a of the table groove portion 60. The wall surface 20b (FIG. 2) on the side of the second ring portion 25 of the second member 22 facing the coil base 50 constitutes the second wall surface 60b of the table groove portion 60. The table groove portion 60 is a donut-shaped (hollow cylindrical) groove that is recessed inward from the outer peripheral surface of the table 20 in the radial direction of the bearing.

With reference to FIG. 5A, an annular recess 61 extending in the circumferential direction is formed on the surface of the first annular portion 23 on the side facing the second member 22, that is, on the first wall surface 60a of the table groove portion 60. Has been done. Further, the surface of the second annular portion 25 on the side facing the first member 21, that is, the second wall surface 60b of the table groove portion 60 has the same diameter and depth as the recess 61 and extends in the circumferential direction. An annular recess 62 is formed. Further, on the inner peripheral side of the first cylinder portion 24 and the second cylinder portion 26, a recess 28 is formed which is recessed outward in the radial direction. With reference to FIG. 5B, the outer ring 32 of the bearing 30 is sandwiched in the recess 28. That is, the recess 28 constitutes the housing of the outer ring 32 of the bearing 30. The outer ring 32 is sandwiched by the first member 21 and the second member 22 of the table 20. Specifically, the outer ring 32 is fixed to the table 20 by the fastening force of the screw 47 (FIGS. 1 and 15) for fastening the first member 21 and the second member 22. In order to securely fix the outer ring 32 and the table 20, in addition to fixing by sandwiching, an adhesive or the like may be used for bonding. Further, at the boundary between the first member 21 and the second member 22 in the recess 28, a groove 29 is formed in which the corners of the first member 21 and the second member 22 are chamfered. By chamfering the first member 21 and the second member 22, the bearing 30 can be easily inserted.

FIG. 6 is a perspective view showing only the second member 22 of the table 20 taken out. FIG. 7 is a diagram showing the fit of the second member 22 and the second magnet row 400. With reference to FIGS. 6 and 7, the second member 22 has a second annular portion 25 and a second tubular portion 26 which is a cylindrical portion that rises from the inner circumference of the second annular portion 25 and extends in the axial direction. And, including. The upper surface (the surface shown in the figure) of the second annular portion 25 constitutes the second wall surface 60b of the table groove portion 60. An annular recess 62 extending in the circumferential direction is formed on the second wall surface 60b.

Magnets 401 are arranged side by side in the recess 62 along the rotation direction (circumferential direction) of the bearing. The magnet 401 is a plate-shaped magnet having a substantially trapezoidal surface that converges toward the center of rotation. The depth of the recess 62 is formed to be substantially equal to the thickness of the magnet 401. That is, the magnet 401 is substantially housed in the recess 62, and the protrusion from the surface of the table 20 is slight. Twenty-one magnets 401 arranged adjacent to each other form the second magnet row 400. The magnet 401 is arranged over about 315 ° out of 360 ° all around the recess 62. A pin hole 620 is formed on the bottom surface of the recess 62. The pin hole 620 can be used to easily position the starting point when arranging the magnet 401. In the second magnet row 400, the magnets 401 are arranged so that the north pole and the south pole alternate with each other. In the first embodiment, the second magnet row 400 has 21 magnets 401 arranged over about 315 °, but the number of magnets and the form of the arrangement are not limited to this. For example, the magnet can be arranged over the entire circumference (360 °) of the recess 62. The number and arrangement of magnets can be appropriately changed depending on the size and performance of the magnets, the torque and rotation speed required for the motor, other configurations of the rotary table device (for example, the arrangement of limit sensors), and the like.

FIG. 8 is a perspective view showing only the first member 21 of the table 20 taken out. FIG. 9 is a diagram showing the fit of the first member 21 and the first magnet row 200. The first member 21 has almost the same form as the second member 22. Here, different configurations will be mainly described. A stopper fixing portion 210 is formed at one of the peripheral edges of the first annular portion 23 of the first member 21. The stopper fixing portion 210 is formed as a recess. Since the stopper fixing portion 210 is formed as a recess, when the fixing screw 211 (FIG. 1) for fixing the stopper arranged on the lower surface of the first member 21 is inserted, the head of the fixing screw 211 is placed on the table 20. Does not protrude to the surface. Further, the outer diameter of the first annular portion 23 of the first member 21 is slightly larger than the outer diameter of the second annular portion 25 of the second member 22. The first annular portion 23 is formed with a screw hole 9 that penetrates the first annular portion 23 in the thickness direction. In the first embodiment, eight screw holes 9 are provided at equal intervals in the circumferential direction, but the number is not particularly limited. The screw hole 9 is used to attach the rotary table device 1 to a work or the like of another member. The first cylinder portion 24 is provided with a screw hole 27a that penetrates the first member in the thickness direction. The screw hole 27a corresponds to the screw hole 27b of the second member 22. The first member 21 and the second member 22 are fixed to each other by inserting and fastening the screws 47 (FIGS. 1 and 15) from the upper surface of the first member 21 into the screw holes 27a and 27b.

With reference to FIGS. 8 and 9, the lower surface (the surface appearing in the figure) of the first annular portion 23 constitutes the first wall surface 60a of the table groove portion 60. An annular recess 61 extending in the circumferential direction is formed on the first wall surface 60a. Magnets 201 are arranged side by side in the recess 61 along the rotation direction (circumferential direction) of the bearing. Twenty-one magnets 201 arranged adjacent to each other form the first magnet row 200. The configuration of the first magnet row 200 is the same as the configuration of the second magnet row 400. A pin hole 610 is formed on the bottom surface of the recess 61 to facilitate the start positioning of the first magnet row 200. The first magnet row 200 and the second magnet row 400 are arranged at the same position in the circumferential direction of the rotary table device.

Next, the coil base 50 of the rotary table device 1 will be described in more detail.
FIG. 10 is a perspective view showing only the coil base 50 taken out. FIG. 11 is a cross-sectional perspective view showing a state in which the coil base 50 is cut at CC in FIG. The entire coil base 50 is a steel plate-shaped member. With reference to FIG. 10, a circular hole centered on the rotation axis (rotation axis of the table 20) R of the bearing is formed in the center of the coil base 50. The peripheral wall 50d defining the circular hole is separated from the outer peripheral surface of the first cylinder portion 24 of the table 20 and the outer peripheral surface of the second cylinder portion 26, that is, the inner peripheral wall surface 60c (FIG. 4) defining the table groove portion 60. While facing each other. The diameter of the circle defined by the peripheral wall 50d is slightly larger than the diameter of the inner peripheral wall surface 60c of the table groove portion 60.

With reference to FIG. 10, screw holes 58 for fixing the coil base 50 to the support column 41 are formed at the four corners of the coil base 50. The four corners of the coil base 50 have an arc shape forming a part of a circular arc centered on the rotation axis R. Further, the coil base 50 has an expansion portion 55 protruding outward from the quadrangle defined by the bed 40. The expansion portion 55 is formed with a screw hole 59 for inserting a screw for fixing the coil base 50 to the encoder head 710 (FIG. 1).

With reference to FIGS. 10 and 11, the coil base 50 has a first surface 50a and a second surface 50b. FIG. 10 shows the first surface 50a of the coil base 50. The first surface 50a is formed with a first recess 51, which is an annular recess extending in the circumferential direction of the rotation of the bearing. With reference to FIG. 11, the second surface 50b is also formed with a second recess 52, which is an annular recess extending in the circumferential direction of the rotation of the bearing. The first recess 51 and the second recess 52 have the same width and depth as each other. A plurality of holes 57 for inserting fixing pins (FIG. 12) for fixing the coil are formed on the bottom surface of the first recess 51 in the circumferential direction. The holes 57 penetrate from the first surface 50a to the second surface 50b, and the two holes are arranged as a set. A pin is inserted from the first surface 50a into one of the two holes in the set, and a pin is inserted from the second surface 50b into the other.

FIG. 12 is a perspective view showing the coil base 50 and the substrate taken out. With reference to FIGS. 10 and 12, the first substrate 81 is arranged so as to be in contact with the first surface 50a of the coil base 50. The first substrate 81 is attached so as to cover the entire circumference of the first recess 51. A coil is attached to the surface of the first substrate 81 on the side facing the coil base 50 (see FIGS. 13 and 14). The same applies to the second surface 50b. That is, the second substrate 82 (FIG. 2) is arranged so as to be in contact with the second surface 50b. The second substrate 82 is attached so as to cover the entire circumference of the second recess 52. A coil is attached to the surface of the second substrate 82 on the side facing the coil base 50. With this configuration, the coil is housed in each of the first recess 51 and the second recess 52 provided on both sides of the coil base 50. The first substrate 81 and the second substrate 82 are, for example, printed circuit boards. Three electric wires corresponding to the U phase, the V phase, and the W phase are connected to the first substrate 81 and the second substrate 82, respectively. Each of the three wires supplies U-phase, V-phase, and W-phase currents to the first coil row 100 and the second coil row 300 attached to the first substrate 81 and the second substrate 82. The first coil row 100 and the second coil row 300 are connected to the drive circuit 600 described later via the first substrate 81 and the second substrate 82.

13 and 14 are perspective views showing the substrate and the coil taken out. FIG. 13 shows the side of the first substrate 81 facing the table 20 (see FIG. 2). FIG. 14 shows the side of the first substrate 81 facing the coil base 50. With reference to FIG. 14, twelve coils 101 are arranged adjacent to each other on the surface of the first substrate 81 along the circumference of the first substrate 81. A collar 110 is arranged in each of the coils 101, and a fixing hole 111 is formed in the collar 110. The first coil row 100 is fixed to the coil base 50 by a fixing pin (not shown) inserted so as to extend over the fixing hole 111 and the hole 57 of the coil base 50 (FIG. 10). The second substrate 82 also has the same configuration, and the description thereof will be omitted. An insulating film (not shown) is attached to the first substrate 81 and the second substrate 82.

With reference to FIG. 14, each coil 101 is a flat, annularly wound coreless coil. Twelve coils 101 constitute the first coil row 100. The coil 101 is a three-phase coil, and in the first coil row 100, the U phase, the V phase, and the W phase are repeatedly arranged in this order from one end. Although the coil row includes 12 coils in the first embodiment, the number and arrangement of the coils included in the coil row can be changed according to the size of the motor and the required torque. With reference to FIGS. 2 and 14, the first coil row 100 and the second coil row 300 are arranged on both sides of the coil base 50, respectively. The number of coils constituting the first coil row 100 and the second coil row 300 is equal to each other. Further, in the first coil row 100 and the second coil row 300, the coils of the same phase can be arranged at the same position in the circumferential direction. With this configuration, it is possible to obtain a large torque by matching the directions of the torques output from the two motors.

Next, the motor included in the rotary table device will be described in detail.
With reference to FIG. 2, the coil 101 is arranged on the first surface 50a of the coil base 50. The magnet 201 is arranged on the wall surface 20a of the table 20 so as to face the coil 101. As described above, the coil 101 constitutes the first coil row 100, and the magnet 201 constitutes the first magnet row 200. A first substrate 81 exists between the first coil row 100 and the first magnet row 200, and the first coil row 100 and the first magnet row 200 are separated from each other. The first coil row 100 and the first magnet row 200 constitute the first motor 150. The same applies to the second surface 50b of the coil base 50. That is, on the second surface side of the coil base, the second coil row 300 and the second magnet row 400 face each other to form the second motor 350.

In the rotary table device 1 of the present disclosure, recesses are formed on both sides of the coil base 50, and coil rows are housed in the recesses. Further, the coil base 50 is arranged so as to enter the table groove portion 60 of the table 20. Further, a recess is provided on the surface of the table 20 facing the coil base 50, and a magnet row is housed in the recess. With these configurations, even when the motors are stacked in two stages, an increase in dimensions in the axial direction can be suppressed, and a compact rotary table device can be realized.

Next, other configurations will be described.
With reference to FIGS. 1 and 15, stoppers 220 are attached to two of the four corners of the coil base 50. A resin portion 222 is provided on each of the two stoppers 220 facing each other. Further, the stopper fixing portion 210 of the table 20 is located between the two stoppers 220. A stopper facing the stopper 220 in the rotation direction is fixed to the lower portion of the stopper fixing portion 210. The two stoppers 220 attached to the coil base 50 are fixed, and the stoppers attached to the table rotate together with the table. The stopper 220 prevents the table 20 from over-rotating.

With reference to FIG. 1, a scale 709 (FIG. 16) extending in the circumferential direction is attached to the outer peripheral side surface of the second member 22 of the table 20. The scale 709 is preferably provided in a portion corresponding to the back of the

columns

41a and 41b. An encoder head 710 is provided facing the scale 709. By arranging the scale 709 behind the support column when viewed from the outside of the rotary table device, it is possible to prevent the adhesion of dust and the like. A signal line is connected to the encoder head 710. Further, electric wires for supplying a three-phase current to the

coils

101 and 301 are arranged.

FIG. 16 is a schematic diagram showing an electrical connection of the rotary table device 1. In particular, the electrical connection between the first motor 150 and the second motor 350 is shown. With reference to FIG. 16, the rotary table device 1 includes a drive driver 700, a drive unit 410, a scale 709 attached to the drive unit, and an encoder head 710 for detecting the operation of the drive unit 410. The encoder head 710 is connected to a control circuit 500 described later. The scale 709 and the encoder head 710 constitute an encoder system 720. The encoder system 720 is connected to the control circuit 500. The control circuit 500 controls the drive circuit 600 according to the output signal of the encoder head 710. The drive driver 700 includes a control circuit 500 and a drive circuit 600. A power supply (not shown) is connected to the drive driver 700. The control circuit 500 controls the drive circuit 600 according to a preset program and according to a signal from the encoder head 710. The drive circuit 600 sends out a current having a phase corresponding to each of the U phase, the V phase, and the W phase. The electric wires L ₁ , L ₂ , and L ₃ are branched and connected to the first motor 150 and the second motor 350, respectively. That is, the first motor 150 and the second motor 350 are electrically connected in parallel with the drive circuit 600. According to this configuration, two motors are operated simultaneously by one drive circuit. Therefore, control for synchronizing the motors is not required, and the two motors can be reliably and easily operated to obtain torque from the two motors. The rotary table device 1 of the present disclosure is a direct drive type device in which the first motor 150 and the second motor 350 are operated by the current from the drive circuit 600, and the table 20 is moved by the generated torque.

It should be understood that the embodiments disclosed this time are exemplary in all respects and are not restrictive in any respect. The scope of the present invention is defined by the scope of claims, not the above description, and is intended to include all modifications within the meaning and scope of the claims.

1 rotary table device, 10 base part, 20 table, 20a, 20b wall surface, 21 first member, 22 second member, 23 first ring part, 24 first cylinder part, 25 second ring part, 26th 2 cylinders, 27a, 27b holes, 28 recesses, 29 grooves, 30 bearings, 31 inner rings, 32 outer rings, 33 coils, 34 seals, 40 beds, 41a to 41d columns, 42 1st center, 43 2nd center, 44, 45, 46, 47, 48 screws, 50 coil base, 50a, 50b coil base surface, 50d coil base inner peripheral wall, 51, 52 recesses, 55 expansion part, 57, 58, 59 holes, 60 table groove part, 60a, 60b wall surface, 60c inner peripheral wall surface, 61, 62 recesses, 610, 620 pin holes, 81 1st board, 82 2nd board, 91 upper shutter, 92 lower shutter, 100 1st coil row, 101 coil, 110 color, 111 Fixing hole, 150 1st motor, 200 1st magnet row, 201 magnet, 210 stopper fixing part, 211 fixing screw, 220 stopper, 222 resin part, 300 2nd coil row, 301 coil, 350 2nd motor, 400th 2 magnet train, 401 magnet, 410 drive unit, 500 control circuit, 600 drive circuit, 700 drive driver, 709 scale, 710 encoder head, 720 encoder system, 730 fixing hole, L ₁ , L ₂ , L ₃ wire.

Claims

Base and
The bearing installed on the base and
A table rotatably supported with respect to the base via the bearings,
A motor that rotates the table in the direction of rotation of the bearing with respect to the base portion,
Equipped with
In the table, a table groove portion recessed in the radial direction of the bearing is formed in an annular shape on the outer peripheral surface over the entire circumference.
The base includes an annular coil base that enters the table groove and is arranged along the table groove.
The motor is
With the first motor
Including the second motor
The first motor is
A first magnet row, which is a row of magnets arranged along the rotation direction of the bearing, on the wall surface of the table defining the groove portion of the table.
The first surface of the coil base includes a first coil row, which is a row of coils arranged so as to face the first magnet row.
The second motor is
A second magnet row, which is a row of magnets arranged along the rotation direction of the bearing, on the wall surface of the table defining the groove portion of the table.
A second coil row, which is a row of coils arranged so as to face the second magnet row on the second surface of the coil base located on the side opposite to the first surface in the axial direction of the bearing. And, including,
Rotating table device.
A first recess in which the first coil row is arranged is formed on the first surface of the coil base.
A second recess in which the second coil row is arranged is formed on the second surface of the coil base.
The rotary table device according to claim 1.
The wall surface of the table that defines the groove portion of the table is
A first wall surface facing the first surface of the coil base,
Includes a second wall surface facing the second surface of the coil base.
The first wall surface has a first table wall surface portion which is a recess, and the first magnet row is arranged in the first table wall surface portion.
The second wall surface has a second table wall surface portion that is a recess, and the second magnet row is arranged in the second table wall surface portion.
The rotary table device according to claim 1 or 2.
The table includes a first member including a plate-shaped portion and a second member including a plate-shaped portion stacked axially with respect to the first member.
The rotary table device according to any one of claims 1 to 3.
The bearing is a cross roller bearing, and the outer ring of the cross roller bearing is sandwiched between the first member and the second member.
The rotary table device according to claim 4.
The bearing and the coil base have the same center position in the axial direction of the bearing.
The rotary table device according to any one of claims 1 to 5.
A first substrate fixed to the coil base is further provided between the first coil row and the first magnet row.
A second substrate fixed to the coil base is further provided between the second coil row and the second magnet row.
The first coil row is fixed to the first substrate, and the second coil row is fixed to the second substrate.
The rotary table device according to any one of claims 1 to 6.
A drive circuit and a control circuit for controlling the drive circuit are further provided.
The first motor and the second motor are electrically connected in parallel to the drive circuit.
The rotary table device according to any one of claims 1 to 7.