JP2010011531A - Multishaft motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multishaft motor, which is low-cost while materializing the accurate positioning of, for example, a robot. <P>SOLUTION: When an electromagnetic coil 126 is excited by the power supply from a controller CONT, a housing disc 125 and the second disc 122 are magnetized, and driving force based on the attraction of attracting each other is generated, so such driving force is larger than the energizing force of a compressive spring 124, the second disc 122 is attracted by the housing disc 125, and they engage with each other such that they press each other, whereby frictional force works, and it can fix the second shaft 105 to a housing 102. On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the second disc 122 abuts on and engages with the topside of a board 115 on the first shaft 106, according to the energizing force of the compressive spring 124, whereby frictional force works, and the second shaft 105 and the first shaft 106 lock each other, or function as couplings. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a multi-axis motor, and more particularly to a multi-axis motor suitable for use in a transfer robot used in an atmosphere outside the atmosphere such as a vacuum.

  Conventionally, as a means for driving a scalar arm type robot in a chamber separated and separated from the atmosphere side, via a coupling mechanism or a sealing mechanism such as a bellows type driving method, a magnetic coupling driving method, a magnetic fluid seal driving method, etc. A method has been used in which the outputs of several motors arranged therein are combined into a multi-structure shaft, and the multi-structure shaft is introduced into the chamber.

On the other hand, a method in which a motor is installed in an atmosphere separated and separated from the atmosphere side and a driving force is transmitted from the multi-shaft structure into the chamber has been developed as shown in Patent Document 1, for example. That is, according to the technique of Patent Document 1, two robot arms can be independently driven by rotating three coaxial multiple shafts with three direct motors.
Special Table 2002-534282

  However, when a coupling mechanism such as the bellows drive system or magnetic coupling drive system described above is used, the backlash is too large or the torsional rigidity in the rotational direction is too low, resulting in high positioning accuracy. There was a problem that it could not be obtained. On the other hand, in the case of a method in which a rotational force is introduced via a sealing mechanism, there is a problem that outgassing due to a volatile component contained in the sealing material is generated and it is difficult to apply to an ultrahigh vacuum chamber.

  Furthermore, as shown in Patent Document 1, in the case of a three-axis motor in which a partition for separating and separating from the atmosphere side is arranged between the rotor and the stator, since three motors are used, the alignment between components is It becomes difficult and maintenance is difficult. Further, since it is composed of three drive motors, there is a problem that the cost of components such as hardware and control software increases, and the maintenance cost also increases due to the complicated structure.

  The present invention has been made in view of the problems in the prior art, and an object of the present invention is to provide a multi-axis motor that is low-cost while achieving high-precision positioning of a robot, for example.

The multi-axis motor of the present invention is
A housing;
A hollow third shaft enclosed in the housing and rotatably supported with respect to the housing;
A hollow second shaft enclosed in the third shaft and supported rotatably with respect to the third shaft;
A first shaft contained in the second shaft and supported rotatably with respect to the second shaft;
A second motor for driving the third shaft relative to the housing;
A first motor that drives the first shaft relative to the housing;
A first connection state in which the second shaft is connected to at least one of the first shaft and the third shaft, and a second connection state in which the second shaft is connected to the housing. And selecting means adapted to selectively establish the above.

  According to the present invention, by driving only the second motor, it is possible to rotate only the third shaft independently, or when the second shaft is connected to the housing, By driving only one motor, only the first shaft can be rotated independently, or when the second shaft is connected to the first shaft, the second motor and the first By driving the motor, the first shaft, the second shaft, and the third shaft can be simultaneously rotated. For this reason, for example, a mechanism as shown in JP-T-2002-534282 can be used for the first shaft. Since the two robot arms can be operated independently by being connected to the second axis and the third axis, a simple and low-cost configuration can be provided.

  Further, the selection means is a friction member that is attached so as to rotate integrally with the second shaft and is relatively movable, a biasing means that biases the friction member in one direction, Drive means for selectively generating a driving force for driving the friction member in the other direction against the biasing force according to a signal, and when the driving means does not generate a driving force, the friction member The member moves to a position that engages with the at least one shaft or the housing, and when the driving means generates a driving force, the friction member moves to a position that engages with the housing or the at least one shaft. It is preferable to move.

  Furthermore, it is preferable to have a plurality of the friction members.

  Further, it is preferable that the driving means drives the friction member by electromagnetic force.

  Furthermore, the biasing means is preferably a spring.

  Furthermore, the biasing means is preferably a permanent magnet.

  Furthermore, it is preferable that the friction member is made of a magnetic material and is given an attractive force by the permanent magnet.

  Furthermore, a housing disk is attached to the inner periphery of the housing, and the friction member is preferably a second disk that engages with the housing disk by moving in the axial direction with respect to the second shaft.

  Furthermore, the friction member is preferably a friction pad attached to the second shaft and movable in the radial direction.

Furthermore, the second motor has a second stator disposed on the outer periphery of the housing, and a second rotor attached to the outer periphery of the third shaft so as to face the second stator,
The first motor preferably includes a first stator disposed on an outer periphery of the housing and a first rotor attached to the outer periphery of the first shaft so as to face the first stator.

  A second detector disposed on the outer periphery of the housing; a second sensor rotor mounted on the outer periphery of the third shaft for detecting rotation by the second detector; and an outer periphery of the housing. It is preferable to have a first detector arranged and a first sensor rotor attached to the outer periphery of the first shaft in order to detect rotation by the first detector.

  Furthermore, it is preferable that the outside of the housing is in an atmospheric state and the inside of the housing is in an outside atmosphere.

  A preferred embodiment of the present invention is a multi-axis motor that drives two independent scalar arms, which separates a vacuum environment from an atmospheric environment with a sealed housing and is fixed to a process chamber by a top plate flange. It has three coaxial shafts (shafts) for driving two independent scalar arms on the vacuum side formed from the housing. By arranging vacuum bearings between the shafts and between the housings, the shafts are supported rotatably with respect to the housing. A permanent magnet is provided on each of the first shaft and the third shaft, a drive electromagnetic stator is disposed on the outside of the corresponding housing, and two drive motor structures are formed. A second disk is formed on the second shaft, and the housing vacuum side inner wall It is good to arrange a housing disk. The second disk is constrained in the rotational direction with respect to the second axis, and is coupled to be movable in the axial direction. The housing disk is fixed to the housing, and is connected on the magnetic path with an electromagnetic coil disposed outside the housing through the housing. When the electromagnetic coil is excited, an attractive force is generated between the second disk and the housing disk, and the second disk moves in the direction of the housing disk and comes into contact therewith, and is fixed to the housing. In another embodiment, the second disk has a reaction force device comprising a compression spring, and the spring is always compressed against the second shaft. Therefore, when the electromagnetic coil is not energized, the second disk is caused by the spring reaction force. Presses against the first axis and the first and second axes are locked together. In order to detect the positions of the first axis and the third axis, a first axis rotation detector and a third axis rotation detector may be arranged.

  According to one aspect of the present invention, compared to the conventional three-motor configuration, the change to two motors and one lock (or coupling) structure enables reduction of machine parts and simplification of control software. Therefore, cost can be reduced. Also, the reduction of machine parts can reduce the complexity of assembly and maintenance, and further reduce the assembly cost and maintenance cost. Further, the volume is smaller than that of the three motor configurations, and an increase in throughput can be expected. In addition, by adopting the cylindrical lock structure, the radius of the effective friction surface to be contacted can be increased, so that the friction torque is increased and the rigidity on the system is increased.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of the multi-axis motor 100A according to the first embodiment. FIG. 1 (a) shows a state where an electromagnetic coil is excited, and FIG. 1 (b) shows that the electromagnetic coil is not excited. Indicates the state.

  In FIG. 1, a top plate flange 101 is attached to the bottom wall of a process chamber (not shown) maintained in a vacuum atmosphere outside the atmosphere. Opposite to the opening 101a of the top plate flange 101, a bottomed tubular housing 102 made of, for example, stainless steel is disposed, and the space between the periphery of the opening 101a of the top plate flange 101 and the periphery of the upper end of the housing 102 is extendable. A cylindrical metal bellows 103 is connected so as to be sealed. Therefore, the space from the inside of the process chamber to the inside of the housing 102 is a sealed space, and even if the outside of the housing 102 is an atmospheric atmosphere, air does not enter the process chamber from the opening 101a. By providing the bellows 103 in this manner, the housing 102 can be moved toward and away from the top plate flange 101 by an actuator (not shown) without destroying the vacuum atmosphere in the process chamber. If such an operation is unnecessary, the housing 102 can be fixed to the top plate flange 101 by welding or the like.

  Three shafts 104 to 106 arranged coaxially extend into the process chamber through the opening 101 a of the top flange 101. More specifically, the hollow third shaft 104 is supported by the vacuum bearings 107 and 108 with respect to the housing 102 so as to be immovable and rotatable in the axial direction. Further, the hollow second shaft 105 is supported by the vacuum bearings 109 and 110 so as not to move in the axial direction and to be rotatable with respect to the third shaft 104. Further, the solid first shaft 106 is supported by the vacuum bearings 111 and 112 so as not to move in the axial direction and to be rotatable with respect to the second shaft 105. Accordingly, when the housing 102 approaches or separates from the top plate flange 101, the three shafts 104 to 106 are also displaced integrally with the housing 102. Here, the third shaft 104 protrudes above the upper end of the housing 102 that encloses the third shaft 104, the second shaft 105 projects above the upper end of the third shaft 104 that encloses the third shaft 104, and the first shaft 106 If it protrudes above the upper end of the 2nd axis | shaft 104 which encloses, it is suitable for connection, such as an arm. In order to improve the system rigidity, it is preferable to use a DB combination of angular ball bearings as each vacuum bearing. However, if the bearing is of a type that can receive both radial load and axial load, another method can be used. It doesn't matter. Further, both ends of the radially inner shaft extend beyond the ends of the radially outer shaft.

  The second permanent magnet 113 constituting the second rotor is attached to the outer periphery of the lower end of the third shaft 104 in the circumferential direction, but the attachment location is not limited to this. A second stator 114 is attached to the outer periphery of the housing 102 so as to face the second permanent magnet 113. When power is supplied to the second stator 114, the third shaft 104 rotates with respect to the housing 102 due to the magnetic force generated between the second stator 114 and the second permanent magnet 113. The second permanent magnet 113 and the second rotor 114 constitute a second motor.

  On the other hand, a thick disc-shaped substrate 115 (the outer diameter is substantially equal to the outer diameter of the third shaft 104) is fixed to the outer periphery of the lower end of the first shaft 106, and the first rotor is formed on the outer periphery of the substrate 115. The first permanent magnets 116 are attached side by side in the circumferential direction, but the attachment location is not limited to this. A first stator 117 is attached to the outer periphery of the housing 102 so as to face the first permanent magnet 116. When power is supplied to the first stator 117, the first shaft 106 rotates with respect to the housing 102 due to the magnetic force generated between the first stator 117 and the first permanent magnet 116. The first permanent magnet 116 and the first rotor 117 constitute a first motor.

  As in the present embodiment, by placing the second stator 114 and the first stator 117 in the atmospheric environment outside the housing 102, the outgas generated from the coil or the like is isolated from the vacuum environment, and stable rotation is achieved. A direct drive motor capable of generating torque is configured. Further, with the above configuration, the third shaft 104 and the first shaft 106 can be independently rotated and precisely positioned, and a balanced driving performance can be obtained.

  Further, a second sensor rotor 118 is attached to the outer periphery of the third shaft 104, and a second detector 119 is attached to the outer periphery of the housing 102 so as to face the second sensor rotor 118. Yes. The second detector 119 can detect the rotation of the second sensor rotor 118 magnetically, but is not limited to this as long as it can detect the rotation of the second sensor rotor 118, that is, the third shaft 104 with high accuracy. I can't.

  On the other hand, the first sensor rotor 120 is attached to the outer periphery of the substrate 115 attached to the first shaft 106, and the first detection is made to the outer periphery of the housing 102 so as to face the first sensor rotor 120. A vessel 121 is attached. The first detector 121 can also detect the rotation of the first sensor rotor 120 magnetically, but is not limited to this as long as it can detect the rotation of the first sensor rotor 120, that is, the first shaft 106 with high accuracy. I can't.

  A second disk 122 as a friction member having a donut plate shape is attached to the outer periphery of the lower end of the second shaft 105. For example, a structure in which a male serration and a female serration are engaged is formed between the second disk 122 made of a magnetic material and the second shaft 105, and the second disk 122 is integrated with the second shaft 105. However, it is relatively movable in the axial direction.

  A disc-shaped spring support 123 is fixed to the outer periphery of the second shaft 105 so as to face the second disc 122 by welding or the like, and between the second disc 122 and the spring support 123 is attached. A compression spring 124 as a biasing means is arranged to bias the second disk 122 downward in FIG.

  A housing disk 125 made of a magnetic material having a donut plate shape is fixed to the inner periphery of the housing 102 on the compression spring 124 side (the upper side in FIG. 1) of the second disk 122. An electromagnetic coil 126 as drive means is disposed on the outer periphery of the housing 102 so as to face the housing disk 125 having an inner diameter smaller than the outer diameter of the second disk 122, and is connected to the housing disk 125 on a magnetic path. .

  Further, the second stator 114, the first stator 117, the second detector 119, the first detector 121, and the electromagnetic coil 126 are connected to the control device CONT so as to be able to exchange signals.

  Here, when the electromagnetic coil 126 is excited by the power supply from the control device CONT, the housing disk 125 and the second disk 122 are magnetized, and a driving force based on the attractive force attracting each other is generated. If it is larger than the urging force of the compression spring 124, the second disk 122 is sucked into the housing disk 125 as shown in FIG. The two shafts 105 can be fixed to the housing 102 (second connection state). On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the second disk 122 abuts on the upper surface of the substrate 115 of the first shaft 106 according to the biasing force of the compression spring 124 as shown in FIG. Thus, the frictional force acts, and the second shaft 105 and the first shaft 106 are locked to each other or function as a coupling (first connection state). The electromagnetic coil 126, the housing disk 125, the second disk 122, and the compression spring 124 constitute selection means.

  By placing the electromagnetic coil 126 in the atmospheric environment outside the housing 102 as in the present embodiment, the outgas generated therefrom can be isolated from the vacuum environment.

  Here, an example in which the multi-axis motor according to the present embodiment is used in a dual scalar arm robot as described in, for example, JP-T-2002-534282 is considered. The dual scalar arm robot described in JP-T-2002-534282 has two arms that can turn around an axis and move independently in the radial direction. More specifically, the third shaft 104 is connected to the frame of one arm, the first shaft 106 is connected to the frame of the other arm, and the second shaft 105 is connected to the pulley for indirect driving of both arms. Yes.

As shown below, the arm can be driven by rotationally driving the third shaft 104 to the first shaft 106 by a signal from the control device CONT.
(1) In a state where the electromagnetic coil 126 is de-excited by an off signal from the control device CONT, the first shaft 106 and the second shaft 105 are connected, so that the second power supply via the control device CONT By driving the motor and the first motor, the third shaft 104, the second shaft 105, and the first shaft 106 can all be rotated integrally, whereby both arms rotate integrally in the same direction. Further, when it is detected that the third shaft 104 and the first shaft 106 have rotated by a predetermined angle based on the signals from the second detector 119 and the first detector 121, the control device CONT The motor can be stationary.
(2) In a state where the electromagnetic coil 126 is excited by the ON signal from the control device CONT, the second shaft 105 is fixed to the stationary housing 102, so the third shaft 104 and the first shaft 106 are moved in one direction. By rotationally driving, both arms are displaced outward in the radial direction, or by rotationally driving the third shaft 104 and the first shaft 106 in the other direction, both arms are displaced inward in the radial direction. Further, when it is detected that the third shaft 104 and the first shaft 106 have rotated by a predetermined angle based on the signals from the second detector 119 and the first detector 121, the control device CONT The motor can be stationary.

  Conventionally, at least three direct drive motors were required to drive the scalar arm robot, but the multi-axis motor according to the present embodiment having two motors and one selection means drives the scalar arm robot. Therefore, a simple and low-cost robot can be provided. In the present embodiment, a compression spring is used to bias the second disk 122, but various other types of springs such as a tension spring, magnetic attraction, and magnetic repulsion can be employed.

  FIG. 2 is a cross-sectional view of a multi-axis motor 100B according to the second embodiment. In the following embodiments, the electromagnetic coil is shown in a neutral state that is neither on nor off, and the control device CONT and wiring are omitted. Differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 2, a flange-like spring support portion 123b is formed on the outer periphery of the lower end of the second shaft 105 that has entered the recess formed on the upper surface of the substrate 115, and a tension spring is formed between the support portion 105a and the second disk 122. By connecting at 124 b, a downward biasing force is applied to the second disk 122.

  When the electromagnetic coil 126 is excited by the power supply from the control device CONT, the housing disk 125 and the second disk 122 are magnetized, and a driving force based on the suction force attracting each other is generated. Therefore, the driving force is applied to the tension spring 124b. The second disc 122 is attracted to the housing disc 125 and engaged so as to press against each other, so that a frictional force acts and the second shaft 105 can be fixed to the housing 102. . On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the second disk 122 abuts and engages with the upper edge of the substrate 115 of the first shaft 106 according to the urging force of the tension spring 124b, and a frictional force acts. The second shaft 105 and the first shaft 106 lock each other or function as a coupling.

  FIG. 3 is a cross-sectional view of a multi-axis motor 100C according to the third embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 3, a flange-like spring support portion 123 c is formed at the lower end of the second shaft 105 in the vicinity of the upper surface of the disk-shaped substrate 115, and the second disk 122 disposed above the housing disk 125. By arranging the compression spring 124 c on the second disk 122, an upward biasing force is applied to the second disk 122.

  When the electromagnetic coil 126 is excited by the supply of electric power from the control device CONT, the housing disk 125 and the second disk 122 are magnetized, and a driving force based on an attractive force attracting each other is generated. Therefore, the driving force is compressed by the compression spring 124c. The second disc 122 is attracted to the housing disc 125 and engaged so as to press against each other, so that a frictional force acts and the second shaft 105 can be fixed to the housing 102. . On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the second disk 122 comes into contact with and engages with the lower end of the third shaft 104 according to the urging force of the compression spring 124c, and a frictional force acts. Therefore, in the present embodiment, the second shaft 105 and the third shaft 104 are configured to lock each other or act as a coupling.

  FIG. 4 is a cross-sectional view of a multi-axis motor 100D according to the fourth embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 4, the spring support portion 123d of the second shaft 105 and the second disk 122 disposed above the housing disk 125 are connected by a tension spring 124d, so that the second disk 122 is attached upward. Power is given.

  When the electromagnetic coil 126 is excited by the power supply from the control device CONT, the housing disk 125 and the second disk 122 are magnetized, and a driving force based on the suction force attracting each other is generated. Therefore, the driving force is applied to the tension spring 124d. The second disc 122 is attracted to the housing disc 125 and engaged so as to press against each other, so that a frictional force acts and the second shaft 105 can be fixed to the housing 102. . On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the second disk 122 comes into contact with and engages with the lower end of the third shaft 104 according to the biasing force of the tension spring 124d, and a frictional force acts. Therefore, also in this embodiment, the second shaft 105 and the third shaft 104 are configured to lock each other or act as a coupling.

  FIG. 5 is a cross-sectional view of a multi-axis motor 100E according to the fifth embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 5, two second disks and two compression springs are provided. More specifically, an upper second disk 122 is formed above the spring support 123e formed at a position facing the housing disk 125, and a lower second disk 122 ′ is formed below the spring support 123e. Furthermore, an upper compression spring 124e is disposed between the upper second disk 122 and the spring support portion 123e, and a lower compression spring 124e ′ is disposed between the lower second disk 122 ′ and the spring support portion 123e. ing.

  When the electromagnetic coil 126 is excited by power supply from the control device CONT, the housing disk 125 and the second disks 122 and 122 ′ are magnetized, and a driving force based on the suction force attracting each other is generated. If it is greater than the biasing force of the compression springs 124e, 124e ′, the second disks 122, 122 ′ are attracted to the housing disk 125 and engaged with each other so as to press each other. Can be fixed to the housing 102. On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the upper second disk 122 comes into contact with the lower end of the third shaft 104 according to the biasing force of the upper compression spring 124e, and according to the biasing force of the lower compression spring 124e ′. The lower second disk 122 ′ is in contact with the upper surface of the substrate 115 of the first shaft 106, and a frictional force acts on each of them. In this embodiment, it is possible to ensure high rigidity as a lock or coupling.

  FIG. 6 is a cross-sectional view of a multi-axis motor 100F according to the sixth embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 6, two second disks, two tension springs, and two spring support portions are provided. More specifically, the upper second disk 122 is formed between the upper spring support 123f formed on the second shaft 105 above the housing disk 125 and the housing disk 125, and the upper spring support 123f An upper tension spring 124f is disposed between the upper second disk 122 and a lower spring formed at the lower end of the second shaft 105 that has entered the recess formed in the upper surface of the substrate 115 below the housing disk 125. A lower second disk 122 ′ is formed between the support part 123f ′ and the housing disk 125, and a lower tension compression spring 124f ′ is disposed between the lower spring support part 123f ′ and the lower second disk 122 ′. ing.

  When the electromagnetic coil 126 is excited by power supply from the control device CONT, the housing disk 125 and the second disks 122 and 122 ′ are magnetized, and a driving force based on the suction force attracting each other is generated. If it is larger than the urging force of the tension springs 124f, 124f ′, the second disks 122, 122 ′ are attracted to the housing disk 125, and a frictional force acts by engaging the housing disks 125 so as to press each other. Can be fixed to the housing 102. On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the upper second disk 122 abuts on the lower end of the third shaft 104 according to the biasing force of the upper tension spring 124f, and according to the biasing force of the lower tension spring 124e ′. The lower second disk 122 ′ abuts on the upper edge of the substrate 115 of the first shaft 106, and a frictional force acts on each of them. Even in this embodiment, high rigidity as a lock or coupling can be secured.

  FIG. 7 is a cross-sectional view of a multi-axis motor 100G according to the seventh embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 7, the attraction force of a permanent magnet is used as a biasing means for biasing the second disk instead of the spring. More specifically, a donut plate-like groove 115a is formed on the upper surface of the substrate 115 attached to the first shaft 106, and a donut plate-like permanent magnet 130 is fixed in the groove 115a. ing. The thickness of the permanent magnet 130 is thinner than the depth of the groove 115a. Due to the magnetic force of the permanent magnet 130, the second disk 122, which is a magnetic body, is always biased downward. The electromagnetic coil 126, the housing disk 125, the second disk 122, and the permanent magnet 130 constitute selection means.

  When the electromagnetic coil 126 is excited by the power supply from the control device CONT, the housing disk 125 and the second disk 122 are magnetized, and a driving force based on an attractive force attracting each other is generated. The second disk 122 is attracted to the housing disk 125 and is engaged so as to press each other, whereby a frictional force acts and the second shaft 105 can be fixed to the housing 102. On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the second disk 122 abuts on and engages with the upper surface of the substrate 115 in accordance with the magnetic force of the permanent magnet 130, and a frictional force acts. The shaft 106 locks with each other or functions as a coupling.

  FIG. 8 is a sectional view of a multi-axis motor 100H according to the eighth embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 8, the repulsive force of the permanent magnet is used to urge the second disk. More specifically, a donut plate-like permanent magnet 130 is fixed to the upper surface of the substrate 115 attached to the first shaft 106. On the other hand, a donut plate-like permanent magnet 131 is fixed to the lower surface of the second disk 122 disposed above the housing disk 125 so as to face the permanent magnet 130. Here, since the permanent magnets 130 and 131 face each other with the same polarity, a repulsive force is generated between the permanent magnets 130 and 131, so that the second disk 122 is always urged downward. Yes.

  When the electromagnetic coil 126 is excited by the power supply from the control device CONT, the housing disk 125 and the second disk 122 are magnetized, and a driving force based on an attractive force attracting each other is generated. , 131, the second disk 122 is attracted to the housing disk 125, and a frictional force is applied by engaging each other so as to press each other, thereby fixing the second shaft 105 to the housing 102. can do. On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the second disk 122 comes into contact with and engages with the upper surface of the substrate 115 in accordance with the repulsive force between the permanent magnets 130 and 131, and the second friction force acts. The shaft 105 and the first shaft 106 lock each other or function as a coupling.

  FIG. 9 is a sectional view of a multi-axis motor 100I according to the ninth embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 9, the attractive force of the permanent magnet is used to urge the second disk. More specifically, a donut-shaped permanent magnet 130 is fixed to the inner periphery of the lower end of the third shaft 104. Due to the magnetic force of the permanent magnet 130, the second disk 122, which is a magnetic body, is always urged upward.

  When the electromagnetic coil 126 is excited by the power supply from the control device CONT, the housing disk 125 and the second disk 122 are magnetized, and a driving force based on an attractive force attracting each other is generated. The second disk 122 is attracted to the housing disk 125 and is engaged so as to press each other, whereby a frictional force acts and the second shaft 105 can be fixed to the housing 102. On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the second disk 122 comes into contact with and engages with the lower end of the third shaft 104 according to the magnetic force of the permanent magnet 130, and a frictional force acts. The third shaft 104 locks with each other or functions as a coupling.

  FIG. 10 is a sectional view of a multi-axis motor 100J according to the tenth embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 10, the repulsive force of the permanent magnet is used to urge the second disk. More specifically, a donut plate-like permanent magnet 130 is fixed to the inner periphery of the lower end of the third shaft 104 above the housing disk 125, and the upper surface of the second disk 122 disposed below the housing disk 125. The doughnut-shaped permanent magnet 131 is fixed to the permanent magnet 130 so as to face the permanent magnet 130. Here, since the permanent magnets 130 and 131 face each other with the same polarity, a repulsive force is generated between the permanent magnets 130 and 131, so that the second disk 122 is always urged downward. Yes.

  When the electromagnetic coil 126 is excited by the power supply from the control device CONT, the housing disk 125 and the second disk 122 are magnetized, and a driving force based on an attractive force attracting each other is generated. , 131, the second disk 122 is attracted to the housing disk 125, and a frictional force is applied by engaging each other so as to press each other, thereby fixing the second shaft 105 to the housing 102. can do. On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the second disk 122 comes into contact with and engages with the upper surface of the substrate 115 in accordance with the repulsive force between the permanent magnets 130 and 131, and the second friction force acts. The shaft 105 and the first shaft 106 lock each other or function as a coupling.

  FIG. 11 is a sectional view of a multi-axis motor 100K according to the eleventh embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 11, the attraction force of a permanent magnet is used to urge the second disk, and two second disks and two magnets are provided. More specifically, a donut plate-like permanent magnet 130 is fixed to the inner periphery of the lower end of the third shaft 104 above the housing disk 125, and the upper second disk is interposed between the permanent magnet 130 and the housing disk 125. 122 is arranged. On the other hand, a donut plate-like groove 115a is formed on the upper surface of the substrate 115 attached to the first shaft 106, and a donut plate-like permanent magnet 131 is fixed in the groove 115a so as to be permanent. A lower second disk 122 ′ is disposed between the magnet 131 and the housing disk 125. The upper second disk 122, which is a magnetic body, is always biased upward by the magnetic force of the permanent magnet 130, and the lower second disk 122 ', which is a magnetic body, is always biased downward by the magnetic force of the permanent magnet 131. .

  When the electromagnetic coil 126 is excited by power supply from the control device CONT, the housing disk 125 and the second disks 122 and 122 ′ are magnetized, and a driving force based on the suction force attracting each other is generated. If it is larger than the magnetic force of the permanent magnets 130 and 131, the second disks 122 and 122 ′ are attracted to the housing disk 125 and engaged with each other so as to press each other. 102 can be fixed. On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the upper second disk 122 abuts the lower end of the third shaft 104 and the lower second disk 122 ′ is the first shaft 106 according to the magnetic force of the permanent magnets 130 and 131. The second shaft 105, the third shaft 104, and the first shaft 106 are locked to each other or function as a coupling.

  FIG. 12 is a sectional view of a multi-axis motor 100L according to the twelfth embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 12, the repulsive force of the permanent magnet is used to urge the second disk, and two second disks and four permanent magnets are provided. More specifically, a flange-shaped magnet support portion 123 </ b> L is formed on the outer periphery of the second shaft 105 so as to face the housing disk 125. A donut plate-like permanent magnet 130 is fixed to the lower surface of the upper second disk 122 disposed above the magnet support portion 123L, and the donut plate-like permanent magnet 130 is fixed to the upper surface of the magnet support portion 123L facing the magnet. A permanent magnet 131 is fixed. On the other hand, a donut plate-like permanent magnet 133 is fixed to the upper surface of the lower second disk 122 ′ disposed below the magnet support portion 123L, and the donut is fixed to the lower surface of the magnet support portion 123L facing the donut plate. A plate-like permanent magnet 132 is fixed. Here, since the permanent magnets 130, 131, 132, and 133 face each other with the same polarity, a repulsive force is generated between the permanent magnets 130, 131, 132, and 133. The disk 122 is always biased upward, and the lower second disk 122 ′ is always biased downward.

  When the electromagnetic coil 126 is excited by power supply from the control device CONT, the housing disk 125 and the second disks 122 and 122 ′ are magnetized, and a driving force based on the suction force attracting each other is generated. If it is larger than the repulsion of the permanent magnets 130, 131 and 132, 133, the second disks 122, 122 'are attracted to the housing disk 125, and the frictional force acts by engaging them so as to press each other. The shaft 105 can be fixed to the housing 102. On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the upper second disk 122 comes into contact with the lower end of the third shaft 104 according to the repulsive force of the permanent magnets 130 and 131, and according to the repulsive force of the permanent magnets 132 and 133. Then, the lower second disk 122 ′ is brought into contact with and engaged with the upper surface of the substrate 115 of the first shaft 106, and a frictional force acts, so that the second shaft 105, the third shaft 104 and the first shaft 106 are locked to each other. Or it functions as a coupling.

  FIG. 13 is a cross-sectional view of a multi-axis motor 100M according to the thirteenth embodiment. Hereinafter, differences from the first embodiment shown in FIG. 1 will be mainly described. In FIG. 13, a cylindrical housing tube portion 140 is formed on the inner periphery of the housing 102 so as to face the electromagnetic coil 126, and a flange portion 141 is formed on the lower end of the second shaft 105 so as to face the housing tube portion 140. In addition, a plurality of pads 142 are held so as to be movable in the radial direction along the flange portion 141 and not to be relatively rotatable. The pad 142 made of a magnetic material has a shape obtained by dividing a cylinder into a plurality of pieces, and a tension spring 143 is disposed between each pad 142 and the outer periphery of the second shaft 105 so that each pad 142 is always attached. A biasing force is applied so as to pull inward in the radial direction.

  When the electromagnetic coil 126 is excited by the power supply from the control device CONT, the housing cylindrical portion 140 and the pad 142 are magnetized, and a driving force based on the suction force attracting each other is generated. Therefore, the driving force is applied to the tension spring 143. If the force is greater than the urging force, the pad 142 is sucked into the housing cylindrical portion 140 and the friction force acts by engaging the housing 142 so as to press each other, so that the second shaft 105 can be fixed to the housing 102. On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the pad 142 contacts and engages the side surface of the substrate 115 of the first shaft 106 according to the urging force of the tension spring 143, and a frictional force is applied to the second shaft. 105 and the first shaft 104 lock each other or function as a coupling.

  FIG. 14 is a cross-sectional view of a multi-axis motor 100N according to the fourteenth embodiment. Hereinafter, differences from the thirteenth embodiment shown in FIG. 13 will be mainly described. In FIG. 14, a housing flange 144 that extends radially inward from the inner periphery of the housing 102 and goes around the inside of the pad 142 is provided facing the electromagnetic coil 126. On the other hand, on the outer side in the radial direction of the pad 142, permanent magnets 146 are embedded in a cylindrical magnet holder 145 fixed to the inner periphery of the housing 102, and each pad 142 is always attracted so as to be pulled outward in the radial direction. Giving power.

  When the electromagnetic coil 126 is excited by the power supply from the control device CONT, the housing flange 144 and the pad 142 are magnetized, and a driving force based on the attractive force attracting each other is generated. Therefore, the driving force is attracted by the permanent magnet 146. If the force is greater than the force, the pad 142 is attracted toward the housing flange 144 and abuts and engages with the third shaft 104 to apply a frictional force so that the second shaft 105 can be connected to the third shaft 104. On the other hand, if the excitation of the electromagnetic coil 126 is interrupted, the pad 142 comes into contact with and engages with the inner peripheral surface of the magnet holder 145 according to the attractive force of the permanent magnet 146, and the second shaft 105 is engaged. It is fixed to the housing 102.

  The present invention has been described above with reference to the embodiments. However, the present invention should not be construed as being limited to the above-described embodiments, and can be modified or improved as appropriate. For example, the multi-axis motor of the present embodiment can be used not only in a vacuum atmosphere but also in an atmosphere outside the atmosphere.

It is sectional drawing of the multi-axis motor 100A concerning 1st Embodiment. It is sectional drawing of the multi-axis motor 100B concerning 2nd Embodiment. It is sectional drawing of the multi-axis motor 100C concerning 3rd Embodiment. It is sectional drawing of multi-axis motor 100D concerning 4th Embodiment. It is sectional drawing of the multi-axis motor 100E concerning 5th Embodiment. It is sectional drawing of the multi-axis motor 100F concerning 6th Embodiment. It is sectional drawing of the multi-axis motor 100G concerning 7th Embodiment. It is sectional drawing of the multi-axis motor 100H concerning 8th Embodiment. It is sectional drawing of the multi-axis motor 100I concerning 9th Embodiment. It is sectional drawing of the multi-axis motor 100J concerning 10th Embodiment. It is sectional drawing of the multi-axis motor 100K concerning 11th Embodiment. It is sectional drawing of the multi-axis motor 100L concerning 12th Embodiment. It is sectional drawing of the multi-axis motor 100M concerning 13th Embodiment. It is sectional drawing of the multi-axis motor 100N concerning 14th Embodiment.

Explanation of symbols

100A to 100N Multi-axis motor 101 Top plate flange 101a Opening 102 Housing 103 Bellows 104 Third shaft 105 Second shaft 105a Spring support 106 First shaft 107, 108 Vacuum bearing 109, 110 Vacuum bearing 111, 112 Vacuum bearing 113 Permanent magnet 114 Second stator 114 Rotor 115 Substrate 115a Groove 116 Permanent magnet 117 First stator 118 Second sensor rotor 119 Second detector 120 First sensor rotor 121 First detector 122 Disk 123 Spring support portion 123L Magnet support portion 123b Spring support Part 123b lower spring support part 123c spring support part 123d spring support part 123e spring support part 123f upper spring support part 123f lower spring support part 124 compression spring 124b tension spring 124c compression spring 124d tension spring 124e Tension spring 124e upper compression spring 124e lower compression spring 124e compression spring 124f tension spring 124f compression spring 125 housing disk 126 electromagnetic coil 130 permanent magnet 130, 131 permanent magnet 130, 131, 132, 133 permanent magnet 131 permanent magnet 132 permanent magnet 133 Permanent magnet 140 Housing cylinder part 141 Flange part 142 Pad 143 Spring 144 Housing flange 145 Magnet holder 146 Permanent magnet CONT Control device

Claims (12)

A housing;
A hollow third shaft enclosed in the housing and rotatably supported with respect to the housing;
A hollow second shaft enclosed in the third shaft and supported rotatably with respect to the third shaft;
A first shaft contained in the second shaft and supported rotatably with respect to the second shaft;
A second motor for driving the third shaft relative to the housing;
A first motor that drives the first shaft relative to the housing;
A first connection state in which the second shaft is connected to at least one of the first shaft and the third shaft, and a second connection state in which the second shaft is connected to the housing. And a selecting means adapted to selectively establish a multi-axis motor.   The selection means includes a friction member attached so as to rotate integrally with the second shaft and capable of relative movement, a biasing means for biasing the friction member in one direction, and an external signal. And a driving means for selectively generating a driving force for driving the friction member in the other direction against the biasing force, and when the driving means does not generate a driving force, the friction member is When the drive means generates a driving force, the friction member moves to a position engaged with the housing or the at least one shaft. The multi-axis motor according to claim 1.   The multi-axis motor according to claim 2, comprising a plurality of friction members.   The multi-axis motor according to claim 2, wherein the driving unit drives the friction member by electromagnetic force.   The multi-axis motor according to claim 2, wherein the biasing means is a spring.   The multi-axis motor according to claim 2, wherein the biasing unit is a permanent magnet.   The multi-axis motor according to claim 6, wherein the friction member is made of a magnetic material and is given an attractive force by the permanent magnet.   The housing disk is attached to an inner periphery of the housing, and the friction member is a second disk that engages with the housing disk by moving in an axial direction with respect to the second shaft. The multi-axis motor according to any one of 2 to 7.   The multi-axis motor according to claim 2, wherein the friction member is a friction pad that is attached to the second shaft and is movable in a radial direction. The second motor has a second stator disposed on the outer periphery of the housing, and a second rotor attached to the outer periphery of the third shaft so as to face the second stator,
The first motor includes a first stator disposed on an outer periphery of the housing, and a first rotor attached to the outer periphery of the first shaft so as to face the first stator. The multi-axis motor according to claim 1.   A second detector disposed on the outer periphery of the housing; a second sensor rotor attached to the outer periphery of the third shaft for detecting rotation by the second detector; and an outer periphery of the housing. The first detector and a first sensor rotor attached to the outer periphery of the first shaft so as to detect rotation by the first detector. The multi-axis motor described in the above.   The multi-axis motor according to claim 1, wherein the outside of the housing is in an atmospheric state, and the inside of the housing is in an outside atmosphere.

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