JP2012010516A - Motor device, driving method for rotor, and robot device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor device capable of generating a high torque, a driving method of a rotor, and a robot device.SOLUTION: The motor device comprises: a rotor; a transmission part suspended on at least a part of a circumference of the rotor; and a drive part to move the transmission part for a fixed distance between the rotor and a contact part in a torque transmission state and return the transmission part to a prescribed position in a state in which the torque transmission state is canceled. A part of the rotor also serves as a part of a detection part to detect information concerning rotation of the rotor.

Description

  The present invention relates to a motor device, a rotor driving method, and a robot apparatus.

  For example, a motor device is used as an actuator for driving a turning machine. As such a motor device, a motor device capable of generating a high torque, such as an electric motor or an ultrasonic motor, is widely known. In recent years, motor devices that drive more precise parts such as the joint parts of humanoid robots have been demanded. Even in existing motors such as electric motors and ultrasonic motors, miniaturization and high torque controllability are required. There is a demand for a configuration that can perform accurate driving.

Japanese Patent Laid-Open No. 2-311237

  However, in an electric motor or an ultrasonic motor, it is necessary to attach a reduction gear in order to generate a high torque, so there is a limit to downsizing. In addition, in an ultrasonic motor, it is difficult to control torque.

  In view of the circumstances as described above, an object of the present invention is to provide a motor device, a rotor driving method, and a robot device capable of generating high torque.

  According to the first aspect of the present invention, the transmission unit is fixed with the rotor, the transmission unit hung on at least a part of the outer periphery of the rotor, and the rotor and the contact unit as a rotational force transmission state. A drive unit that moves the distance and returns the transmission unit to a predetermined position in a state in which the rotational force transmission state is eliminated, and a part of the rotor is a part of the detection unit that detects information related to the rotation of the rotor. A motor device is also provided.

  According to a second aspect of the present invention, there is provided a robot apparatus that includes a rotary shaft member and a motor device that rotates the rotary shaft member, and the motor device according to the aspect of the present invention is used as the motor device. The

  According to the third aspect of the present invention, the state where the transmission unit is moved a certain distance with the rotational force transmission state between the rotor and the transmission unit hung on the rotor, and the rotational force transmission state is eliminated To return the transmission unit to a predetermined position, and to detect information about the rotation of the rotor using a part of the rotor that also serves as a part of the detection unit that detects information about the rotation of the rotor. A rotor driving method is provided.

  According to the present invention, high torque can be generated.

The perspective view which shows the structure of the motor apparatus which concerns on 1st embodiment of this invention. FIG. 3 is a cross-sectional view illustrating a partial configuration of the motor device according to the embodiment. FIG. 3 is a cross-sectional view illustrating a partial configuration of the motor device according to the embodiment. The figure which shows the structure of a part of motor apparatus which concerns on this embodiment. The graph which shows the characteristic of the motor apparatus which concerns on this embodiment. The figure which shows operation | movement of the motor apparatus which concerns on this embodiment. The figure which shows operation | movement of the motor apparatus which concerns on this embodiment. The figure which shows operation | movement of the motor apparatus which concerns on this embodiment. The figure which shows operation | movement of the motor apparatus which concerns on this embodiment. The figure which shows operation | movement of the motor apparatus which concerns on 2nd embodiment of this invention. The figure which shows operation | movement of the motor apparatus which concerns on this embodiment. The figure which shows operation | movement of the motor apparatus which concerns on this embodiment. The figure which shows operation | movement of the motor apparatus which concerns on this embodiment. The figure which shows operation | movement of the motor apparatus which concerns on this embodiment. The figure which shows operation | movement of the motor apparatus which concerns on this embodiment. The schematic diagram which shows the structure of the robot hand which concerns on 4th embodiment of this invention. The figure which shows the structure of the motor apparatus which concerns on the modification of this invention. The figure which shows the structure of the motor apparatus which concerns on the modification of this invention. The figure which shows the structure of the motor apparatus which concerns on the modification of this invention. The figure which shows the structure of the motor apparatus which concerns on the modification of this invention. The figure which shows the structure of the motor apparatus which concerns on the modification of this invention. The figure which shows the structure of the motor apparatus which concerns on the modification of this invention.

[First embodiment]
Hereinafter, a first embodiment of the present invention will be described based on the drawings. FIG. 1 is a schematic configuration diagram illustrating an example of a motor device MTR according to the present embodiment. FIG. 2 is a diagram showing a configuration along the AA ′ cross section in FIG. 1. FIG. 3 is a diagram showing a configuration along the BB ′ cross section in FIG. 1. As shown in FIGS. 1 to 3, the motor device MTR includes a base part BS, a rotor SF, a drive part AC, a transmission member BT, a detection part DT, and a control part CONT.

  Base part BS is a part formed in plate shape using materials, such as stainless steel, for example, and supports rotor SF, transmission member BT, drive part AC, and control part CONT. The rotor SF is formed in a columnar shape using a metal material such as stainless steel or aluminum, and rotates about the central axis C as a rotation axis. The rotor SF is rotatably supported by, for example, a bearing device (not shown). The bearing device is supported by, for example, the base portion BS. For example, the control part CONT may be supported by another member instead of the base part BS.

  The rotor SF has a belt hook portion 11 and a flange portion 12. The belt hook portion 11 is formed to have a diameter equal to the extending direction (Z direction) of the central axis C of the rotor SF. The collar portion 12 is provided, for example, at an end portion on the −Z side of the belt hanging portion 11, and is formed in a disk shape so as to have a larger diameter than the belt hanging portion 11. The belt hook portion 11 and the flange portion 12 are formed as one member, for example. For this reason, the belt hook part 11 and the collar part 12 rotate integrally. Moreover, since the belt hook part 11 and the collar part 12 are formed using the metal material, they have high vibration resistance and impact resistance.

  Hereinafter, in the description of each drawing, an XYZ orthogonal coordinate system is set, and the positional relationship of each member will be described with reference to this XYZ orthogonal coordinate system. A cylindrical axis direction of the rotor SF is defined as a Z-axis direction, and orthogonal directions on a plane perpendicular to the Z-axis direction are defined as an X-axis direction and a Y-axis direction, respectively. In addition, the rotation (inclination) directions around the X axis, Y axis, and Z axis are the θX direction, θY direction, and θZ direction, respectively. For the θX, θY, and θZ directions, the counterclockwise direction when viewed in the positive direction (arrow direction) of the X, Y, and Z axes is defined as the positive direction. Is the negative direction.

  The drive unit AC includes, for example, a first drive unit AC1 and a second drive unit AC2. The first drive part AC1 and the second drive part AC2 are both provided in the base part BS, for example. The base part BS is provided with connection parts 141 and 142 and connection parts 241 and 242. The first drive unit AC1 includes drive elements 131 and 132. The drive element 131 is attached to the connection part 141, and the drive element 132 is attached to the connection part 142.

  As the drive elements 131 and 132, for example, electromechanical conversion elements such as piezo elements are used. The drive elements 131 and 132 are configured to expand and contract in the X direction when a voltage is applied to the electromechanical conversion element. The control unit CONT is connected to the drive elements 131 and 132 of the first drive unit AC1, and can supply control signals to the drive elements 131 and 132.

  The second drive unit AC2 includes drive elements 231 and 232. The drive element 231 is attached to the connection portion 241, and the drive element 132 is attached to the connection portion 142. As the drive elements 231 and 232, for example, as in the case of the drive elements 131 and 132, an electromechanical conversion element such as a piezo element is used. The drive elements 231 and 232 are configured to expand and contract in the X direction when a voltage is applied to the electromechanical conversion element. The control unit CONT is connected to the drive elements 231 and 232 of the second drive unit AC2, and can supply control signals to the drive elements 231 and 232.

  The positions of the driving elements 131 and 132 on the + X side are fixed by the connecting portions 141 and 142. For this reason, when the drive elements 131 and 132 expand and contract in the X direction, the position in the X direction of the end portion on the −X side changes with the expansion and contraction. Similarly, the positions of the driving elements 231 and 232 on the + X side are fixed by the connecting portions 241 and 242. For this reason, the positions of the drive elements 231 and 232 in the X direction at the end portion on the −X side change with the expansion and contraction.

  The transmission member BT includes, for example, a first transmission member BT1 connected to the first drive unit AC1 and a second transmission member BT2 connected to the second drive unit AC2. The first transmission member BT1 has a first end 121, a second end 122, and a belt 123. The first end 121 is connected to the end of the drive element 131 on the −X side. The second end 122 is connected to the −X side end of the drive element 132.

  The first end 121 and the second end 122 are arranged with a reference position F (see FIG. 2) on the outer periphery of the rotor SF interposed therebetween. In the present embodiment, the case where the + X side end of the rotor SF is set as the reference position F will be described as an example. The belt part 123 is hung on the belt hook part 11 of the rotor SF.

  The second transmission member BT2 has a first end 221, a second end 222, and a belt 223. The first end 221 is connected to the end on the −X side of the drive element 231. The second end 222 is connected to the −X side end of the drive element 232. Similar to the first transmission member BT1, the first end 221 and the second end 222 are disposed with a reference position F (see FIG. 2) on the outer periphery of the rotor SF interposed therebetween. In the present embodiment, the case where the + X side end of the rotor SF is set as the reference position F will be described as an example. The belt portion 223 is hung on the belt hook portion 11 of the rotor SF. The belt part 123 and the belt part 223 are arranged in parallel, for example.

  When the drive elements 131 and 132 of the first drive unit AC1 contract, the first end 121 and the second end 122 move in the + X direction. For this reason, the belt part 123 is wound around the rotor SF, and tension is applied to the belt part 123. When the drive elements 131 and 132 extend, the first end 121 and the second end 122 move in the −X direction. For this reason, the belt part 123 moves away from the rotor SF and relaxes.

  Similarly, in the second drive unit AC2, when the drive elements 231 and 232 contract, the first end 221 and the second end 222 move in the + X direction. For this reason, the belt portion 223 is wound around the rotor SF, and tension is applied to the belt portion 223. When the drive elements 231 and 232 extend, the first end 221 and the second end 222 move in the −X direction. For this reason, the belt portion 223 moves away from the rotor SF and relaxes.

  The detection unit DT detects information about rotation (rotation related information) such as the rotation speed, rotation angle, and rotation speed of the rotor SF. For example, as illustrated in FIG. 1 and the like, the detection unit DT includes a light reflection pattern EP and an optical sensor SR. The light reflection pattern EP is formed on the end surface 12 a on the −Z side of the flange portion 12. The optical sensor SR is disposed to face the end surface 12a of the rotor SF. The optical sensor SR is supported by a support unit (not shown). Thus, in the present embodiment, the light reflection pattern EP that is a part of the rotor SF is configured to also serve as a part of the detection unit DT.

FIG. 4 is an enlarged cross-sectional view of the flange 12.
As shown in FIG. 4, the light reflection pattern EP includes a plurality of slit-like light reflection portions 10 having a length in the radial direction of the end surface 12 a, for example. The several light reflection part 10 is arrange | positioned radially along the peripheral part of the end surface 12a (refer FIG. 1). The light reflecting portion 10 is formed in a thin film shape by, for example, a material that reflects light (for example, aluminum). Further, a region of the end surface 12a that is separated from the light reflecting portion 10 is covered with, for example, a material that absorbs light (for example, black nickel).

  The optical sensor SR includes a fixed slit 13, a light receiving element 14, a waveform shaping circuit 15, and a light emitting element 16. The light emitting element 16 emits the detection light L toward the light reflection pattern EP. As the light emitting element 16, for example, an LED or a laser diode is used. The fixed slit 13 is a light shielding pattern formed in a lattice shape. The light receiving element 14 receives the detection light L and generates an electrical signal. For example, a photodiode or the like is used as the light receiving element 14. The waveform shaping circuit 15 converts the electrical signal generated by the light receiving element 14 into a pulse signal, and transmits the pulse signal to the control unit CONT.

  The detection unit DT has a configuration in which the detection light L emitted from the light emitting element 16 is irradiated on the light reflection pattern EP, reflected by the light reflection unit 10, passes through the fixed slit 13, and is received by the light receiving element 14. It has become. Due to the rotation of the rotor SF, the amount of light reflected by the light reflecting section 10 changes. In the detection unit DT, the change in the amount of the reflected light is detected by the light receiving element 14 as information on the rotation of the rotor SF.

  In the optical sensor SR, an output electrical signal corresponding to the amount of received light is generated in the light receiving element 14, converted into a pulse signal in the waveform shaping circuit 15, and then transmitted to the control unit CONT. The control unit CONT controls the rotation of the rotor SF based on the pulse signal.

Next, the operation of the motor device MTR will be described.
In the motor device MTR according to the present embodiment, the principle of applying torque to the rotor SF will be described. When driving the rotor SF, an effective tension is generated in the transmission member BT (at least one of the first transmission member BT1 and the second transmission member BT2) wound around the rotor SF, and the rotor is generated by the effective tension. Torque is transmitted to SF. Hereinafter, the first drive unit AC1 will be described as the drive unit AC, and the first transmission member BT1 will be described as the transmission member BT. The following description is also applicable to the second drive unit AC2 and the second transmission member BT2.

  According to Euler's friction belt theory, the tension (T1) on the first end 121 side and the tension (T2) on the second end 122 side of the first transmission member BT1 wound around the rotor SF are the following [Equation 1]. When satisfying the above, the frictional force is generated between the first transmission member BT1 and the rotor SF, and the rotor is in a state where the first transmission member BT1 does not slip with respect to the rotor SF (rotational force transmission state). Move with SF. By this movement, torque is transmitted to the rotor SF. In [Equation 1], μ is an apparent coefficient of friction between the first transmission member BT1 and the rotor SF, and θ is an effective winding angle of the first transmission member BT1.

  At this time, the effective tension contributing to torque transmission is represented by (T1-T2). When the effective tension (T1-T2) is obtained based on the above [Equation 1], [Equation 2] is obtained. [Equation 2] is an expression representing an effective tension using T1.

  From the above [Equation 2], it can be seen that the torque transmitted to the rotor SF is uniquely determined by the tension T1 of the drive element 131 of the first drive unit AC1. The coefficient portion of T1 on the right side of [Formula 2] depends on the friction coefficient μ between the first transmission member BT1 and the rotor SF and the effective winding angle θ of the first transmission member BT1, respectively. FIG. 5 is a graph showing the relationship between the effective winding angle θ and the value of the coefficient portion when the friction coefficient μ is changed. The horizontal axis of the graph indicates the effective winding angle θ, and the vertical axis of the graph indicates the value of the coefficient portion.

  As shown in FIG. 5, for example, when the friction coefficient μ is 0.3, the value of the coefficient portion is 0.8 or more when the effective winding angle θ is 300 ° or more. From this, when the friction coefficient μ is 0.3, by setting the effective winding angle θ to 300 ° or more, a force of 80% or more of the tension T1 by the drive element 131 contributes to the torque of the rotor SF. I understand that. In addition to the winding angle, it is estimated from the graph of FIG. 5 that, for example, the value of the coefficient portion increases as the friction coefficient between the first transmission member BT1 and the rotor SF increases.

  In this way, the magnitude of the torque is uniquely determined by the tension T1 of the drive element 131, and it can be seen that it is irrelevant to, for example, the moving distance of the first transmission member BT1. Therefore, for example, the piezo element used for the drive element 131 and the drive element 132 can give a force of several hundred newtons or more even if it is a small element of about several millimeters, so that a very large rotational force is applied. Can do.

  Based on such a principle, as shown in FIG. 6, the control unit CONT first sets the drive element 131 and the drive element 132 so that the first end 121 and the second end 122 move in the + X direction, respectively. Deform. By this operation, a tension T1 is generated on the first end 121 side of the first transmission member BT1, and a tension T2 is generated on the second end 122 side of the first transmission member BT1. Accordingly, an effective tension (T1-T2) is generated in the first transmission member BT1.

  As shown in FIG. 7, the control unit CONT maintains the state where the effective tension is generated in the first transmission member BT1 so that the first end 121 of the first transmission member BT1 moves in the −X direction. In addition, the drive element 131 and the drive element 132 are deformed so that the second end portion 122 moves in the + X direction (drive operation). In this operation, the control unit CONT makes the moving distance of the first end 121 and the moving distance of the second end 122 equal. By this operation, the first transmission member BT1 moves in a state where a frictional force is generated between the first transmission member BT1 and the rotor SF, and the rotor SF rotates in the + θZ direction along with the movement.

  After the first end 121 and the second end 122 are moved by the first distance, the control unit CONT prevents the first end 121 from moving as shown in FIG. Only the drive element 132 is deformed so that the unit 122 returns to the drive start position. By this operation, the second end 122 moves in the −X direction, and the first transmission member BT1 is loosely wound. That is, the effective tension applied to the first transmission member BT1 is released. In this state, no frictional force is generated between the first transmission member BT1 and the rotor SF, and the rotor SF continues to rotate due to inertia.

  After loosening the winding of the first transmission member BT1, the control unit CONT deforms the drive element 131 so that the first end 121 returns to the drive start position, as shown in FIG. With this operation, the first end 121 of the first transmission member BT1 returns to the driving start position while the winding of the first transmission member BT1 is loose, that is, no effective tension is generated (return operation). .

  Immediately before the first end 121 is returned to the drive start position, the control unit CONT deforms the drive element 131 and moves the first end 121 in the + X direction. By this operation, the tension T1 is generated on the first end 121 side and the tension T2 is generated on the second end 122 side almost simultaneously with the return of the first end 121 to the drive start position. Thereby, it will be in the state similar to the state (state of FIG. 6) which added effective tension to the 1st transmission member BT1 at the time of a drive start.

  After the effective tension is applied to the first transmission member BT1, the controller CONT deforms the drive element 131 so that the first end 121 of the first transmission member BT1 moves in the + X direction, and the second end 122 The drive element 132 is deformed so as to move in the + X direction (drive operation). At this time, the moving distance of the first end 121 is made equal to the moving distance of the second end 122. By this operation, the first transmission member BT1 moves in a state where a frictional force is generated between the first transmission member BT1 and the rotor SF, and the rotor SF rotates in the θ direction along with the movement.

  Thereafter, the control part CONT releases again the effective tension added to the first transmission member BT1. After releasing the effective tension, the control unit CONT moves the first transmission member BT1 so that the first end 121 and the second end 122 return to the start position (return operation). As described above, the control unit CONT causes the first driving unit AC1 to repeatedly perform the driving operation and the return operation, so that the rotor SF continues to rotate in the + θZ direction.

  When the control unit CONT causes the operation of the drive element 131 and the operation of the drive element 132 to be switched, the rotor SF rotates in the opposite direction (−θZ direction). Further, the above description is about steps using the first drive unit AC1 and the first transmission member BT1, but for example, the control unit CONT similarly performs the drive operation and the second drive unit AC2. By performing the return operation, the rotor SF can be rotated in the + θZ direction and the −θZ direction, respectively. 6-9, the structure of each part of 2nd drive part AC2 and 2nd transmission member BT2 corresponding to each part of said 1st drive part AC1 and 1st transmission member BT1 is shown with the code | symbol in a parenthesis. Yes.

  As an example of the aspect which drives using both 1st drive part AC1 and 2nd drive part AC2, for example, while the rotational force transmission state between 1st transmission member BT1 and rotor SF is cancelled | released (FIG. 8 and the state shown in FIG. 9, a mode in which the rotational force is transmitted between the second transmission member BT2 and the rotor SF, and the rotor SF is driven to rotate using the second drive unit AC2. It is done. In this way, when the first drive unit AC1 and the second drive unit AC2 are alternately driven, the vibration width of the tension is suppressed to be small, and stable rotation adjustment can be performed.

  As described above, according to the present embodiment, the drive unit AC (first drive unit) with the transmission member BT (the first transmission member BT1 and the second transmission member BT2) hung on at least a part of the rotor SF. Since the drive operation and the return operation are performed by the AC1 and the second drive unit AC2), the torque is uniquely determined by one tension applied to the transmission member BT according to Euler's friction belt theory. Therefore, it is possible to add a high torque to the rotor SF even with a small drive unit AC. Thereby, the small motor apparatus MTR which can generate a high torque can be obtained. Further, even with a small drive unit AC, the rotor SF can be rotated with high efficiency.

  Further, according to the present embodiment, since the light reflection pattern EP that is a part of the rotor SF also serves as a part of the detection unit DT, the number of parts can be reduced accordingly. For this reason, the arrangement space of each part can be saved. Moreover, since rotation is controlled according to the detection result of the detection part DT, the precision of positioning can be improved. Thereby, a highly accurate and small motor device MTR can be provided.

  Further, in this embodiment, since the collar portion 12 on which the light reflection pattern EP is formed is formed of one member with the belt hook portion 11 and is formed of a metal material, for example, the collar portion 12 is made of a glass substrate or the like. The vibration resistance and impact resistance are improved as compared with the case of using them. Thereby, the motor apparatus MTR applicable to a wide use can be provided.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.
The present embodiment is different from the first embodiment in that the elastic deformation of the transmission member BT (the first transmission member BT1 and the second transmission member BT2) is used during the driving operation of the motor device MTR. Therefore, the configuration of the motor device MTR can be the same as that of the first embodiment except that the transmission member BT of the motor device MTR can be elastically deformed. Hereinafter, the first drive unit AC1 is represented as the drive unit AC, and the first transmission member BT1 is represented as the transmission member BT. The following description is also applicable to the second drive unit AC2 and the second transmission member BT2.

In the present embodiment, the spring constant of the first transmission member BT1 is k. Here, the friction belt theory of Euler, set the retaining force T _C of the rotor SF as follows Equation 3]. The holding force T _C, is the force required to reactivate AIBO rotor SF at rest. Further, when the target tension on the first end 121 side is T _1e , the target tension on the second end 122 side is T _2e , and the target effective tension is T _goal , the following [Equation 4] and [Equation 5] are satisfied. .

  Hereinafter, the driving operation of the rotor SF will be mainly described with reference to FIGS. 10-15, the structure of each part of 2nd drive part AC2 and 2nd transmission member BT2 corresponding to each part of 1st drive part AC1 and 1st transmission member BT1 is shown with the code | symbol in parenthesis. In the present embodiment, the configuration of the motor device is schematically shown for easy understanding.

  In the following description, the first end of the first transmission member BT1 is in a state where the first transmission member BT1 is wound around the rotor SF without applying tension to the first transmission member BT1. The positions of the part 121 and the second end part 122 are set to the origin position 0. Therefore, when both the first end 121 and the second end 122 of the first transmission member BT1 are located at the origin position 0, a frictional force is generated between the first transmission member BT1 and the rotor SF. do not do.

<Drive operation>
First, the control unit CONT, as shown in FIG. 10, as the first end portion 121 of the first transmission member BT1 moves only _{X 1} from the origin position 0 + X direction (e.g., toward the base portion BS) The drive element 131 is deformed. The control part CONT, the second end 122 of the first transmission member BT1 only _{X 2} from the origin position 0 + X direction (e.g., toward the base portion BS) to deform the drive element 132 to move. This state is the initial state of the driving operation. At this time, X ₁ and X ₂ satisfy the following [Equation 6].

From this state, as shown in FIG. 11, the control unit CONT deforms the drive element 131 so that the tension T1 on the first end 121 side of the first transmission member BT1 becomes the target tension _T1e . the end 121 by [Delta] X ₁ + X direction (e.g., toward the base portion BS) is moved to. Further, the control unit CONT deforms the drive element 132 so that the second end 122 is moved by ΔX _{2 by} −X direction (for example, the base portion) so that the tension T2 on the second end 122 side becomes the target tension T _2e. Move in a direction away from the BS). By this operation, torque is transmitted from the first transmission member BT1 to the rotor SF. At this time, the relationship of [Equation 7] is established between ΔX ₁ and ΔX ₂ .

When torque is transmitted from the first transmission member BT1 to the rotor SF, the rotor SF rotates and the elastic deformation of the first transmission member BT1 becomes the same state as the initial state. As shown in FIG. 12, balances Thus the tension T ₂ of the tension T ₁ and the second end portion 122 side of the first end portion 121 side of the first transmission member BT1 is a retaining force T _C. At this time, since the effective tension changes approximately linearly from T _goal to zero, the effective effective tension added to the first transmission member BT1 is T _goal / 2. Further, the torque transmitted to the rotor SF by the transmission member BT becomes zero.

<Return operation>
Next, as illustrated in FIG. 13, the control unit CONT moves the first end 121 to the origin position 0 and the second end 122 from the origin position 0 to the −X side (for example, away from the base BS). The drive element 131 and the drive element 132 are simultaneously deformed so as to move in the direction). By deforming the the drive element 131 and drive element 132 for example simultaneously with equal amount of deformation, the first transmission member BT1 is loosen by 2ΔX _1. As a result, a gap is generated between the first transmission member BT1 and the rotor SF. The rotor SF is in an inertial rotation state without receiving a frictional force by the first transmission member BT1.

  While the gap is generated between the first transmission member BT1 and the rotor SF, as shown in FIG. 14, the control unit CONT does not move the first end 121 but only the second end 122. The drive element 132 is deformed so as to return to the origin position 0. By this operation, both the first end 121 and the second end 122 return to the origin position 0. Even in this state, the rotor SF is in an inertial rotation state without receiving a frictional force by the first transmission member BT1. Thus, in the return operation, the first end 121 and the second end 122 are moved to the origin position 0 in a state where the rotor SF is rotated without giving resistance to the rotor SF due to frictional force.

<Drive operation (inertia rotation state)>
The controller CONT detects the outer peripheral speed v of the rotor SF by a detector provided in the rotor SF. The control part CONT determines the moving distance of the 1st end part 121 and the 2nd end part 122 based on a detection result. In the driving operation in a state where the rotor SF is stationary, the initial position of the _first end 121 is X ₁ , and the initial position of the second end 122 is X ₂ (= X ₁ ). In order to apply the same target effective tension to the first transmission member BT1 in a state where the rotor SF is inertially rotated, the same environment as that of the stationary state of the rotor SF is required. That is, the relative speed between the outer periphery of the rotor SF and the first transmission member BT1 needs to be zero. For this reason, in determining the initial position of the first end 121 and the initial position of the second end 122, it is necessary to consider the moving distance per predetermined time of the outer periphery of the rotor SF. As an example, the initial position of the first end 121 is set as X ₁ + vΔt, and the initial position of the second end 122 is set as X ₂ −vΔt. Here, examples of Δt include a sampling time of the control unit CONT.

From this state, as shown in FIG. 15, the control unit CONT deforms the drive element 131 so that the tension T1 on the first end 121 side of the first transmission member BT1 becomes the target tension _T1e . the end 121 by [Delta] X ₁ + X direction (e.g., toward the base portion BS) is moved to. Further, the control unit CONT deforms the driving element 132 so that the second end 122 is moved by ΔX _{2 in the} + X direction (for example, the base unit BS) so that the tension T2 on the second end 122 side becomes the target tension T _2e. In the direction of approaching). By this operation, torque is transmitted from the first transmission member BT1 to the rotor SF. At this time, the first end 121 is moved in the + X direction (for example, the direction approaching the base portion BS) by X ₁ + vΔt + ΔX _{1 with} respect to the origin position 0. At this time, the second end portion 122 is moved in the −X direction (for example, the direction away from the base portion BS) by X ₂ −vΔt−ΔX _{1 with} respect to the origin position.

<Return operation>
Thereafter, the controller CONT is driven so that the first end 121 moves to the origin position 0 and the second end 122 moves in the + X direction (for example, the direction approaching the base BS) from the origin position 0. While the element 131 and the driving element 132 are simultaneously deformed and a gap is generated between the first transmission member BT1 and the rotor SF, only the second end 122 is moved without moving the first end 121. The drive element 132 is deformed so as to return to the origin position 0. By this operation, both the first end 121 and the second end 122 return to the origin position 0. The return operation can be performed as the same operation regardless of the rotation speed of the rotor SF.

Thereafter, the rotor SF can be made by repeating the driving operation and the returning operation. When the rotor SF is in an inertial rotation state, unless the value of X ₁ + vΔt + ΔX ₁ exceeds the maximum deformation amount of the drive element 131, the driving operation and the return operation are repeated, whereby torque is applied to the rotor SF Can continue to communicate.

Next, torque control in the driving operation of the rotor SF of this embodiment will be described.
The effective torque N _e in the present embodiment includes a time t _all required for performing one cycle of the drive operation and the return operation, a time t _e from the start of transmission of the effective tension until the rotor SF enters an inertia state, and a target effective tension. It depends on T _goal and the radius R of the rotor SF. As an example, it is shown by the following [Equation 8].

As shown in [Equation 8], there are three parameters for controlling the effective torque N _e , t _all , t _e , and T _goal . Since the time t _all of one cycle of the drive operation and the return operation may be set constant in performing the drive control of the rotor SF, the effective torque can be obtained by changing two values of t _e and T _goal. it may be provided to control the N _e.

  When the control unit CONT performs the operation of the driving element 131 and the operation of the driving element 132 by exchanging them, the rotor SF rotates in the opposite direction (+ θZ direction). Further, the description of the present embodiment is a drive using the first drive unit AC1 and the first transmission member BT1, but the control unit CONT, for example, similarly drives and returns to the second drive unit AC2. By performing the operation, the rotor SF can be rotated in the + θZ direction and the −θZ direction, respectively. 10-15, the structure of each part of 2nd drive part AC2 and 2nd transmission member BT2 corresponding to each part of said 1st drive part AC1 and 1st transmission member BT1 is shown with the code | symbol in a parenthesis. Yes.

  Thus, according to the present embodiment, the relative speed between the outer periphery of the rotor SF and the transmission member BT is made zero using the elastic deformation of the transmission member BT (first transmission member BT1, second transmission member BT2). By repeatedly performing a driving operation for transmitting the effective tension of the transmission member BT to the rotor SF and a returning operation for simultaneously moving the first end portions 121 and 221 and the second end portions 122 and 222 inward, the rotor The SF can be dynamically rotated while accelerating or decelerating. Moreover, even if it is small drive part AC (1st drive part AC1, 2nd drive part AC2), it becomes possible to rotate the rotor SF with high efficiency.

[Third embodiment]
Next, a third embodiment of the present invention will be described.
FIG. 16 is a diagram illustrating a configuration of a part of the robot apparatus RBT including the motor apparatus MTR or the motor apparatus MTR3 described in any of the above embodiments (for example, the tip of a finger portion).

  As illustrated in FIG. 16, the robot apparatus RBT includes a terminal node portion 101, a middle node portion 102, and a joint portion 103, and the terminal node portion 101 and the middle node portion 102 are connected via the joint portion 103. It has become. The joint portion 103 is provided with a shaft support portion 103a and a shaft portion 103b. The shaft support portion 103 a is fixed to the middle joint portion 102. The shaft portion 103b is supported in a state of being fixed by the shaft support portion 103a.

  The end node portion 101 includes a connecting portion 101a and a gear 101b. The shaft portion 103b of the joint portion 103 is penetrated through the connecting portion 101a, and the end node portion 101 is rotatable with the shaft portion 103b as a rotation axis. The gear 101b is a bevel gear fixed to the connecting portion 101a. The connecting portion 101a rotates integrally with the gear 101b.

  The middle joint portion 102 includes a housing 102a and a driving device ACT. As the drive device ACT, the motor device MTR described in the above embodiment can be used. The driving device ACT is provided in the housing 102a. A rotating shaft member 104a is attached to the driving device ACT. A gear 104b is provided at the tip of the rotating shaft member 104a. The gear 104b is a bevel gear fixed to the rotating shaft member 104a. The gear 104b is in mesh with the gear 101b.

In the robot apparatus RBT configured as described above, the rotation shaft member 104a is rotated by the drive of the drive device ACT, and the gear 104b is rotated integrally with the rotation shaft member 104a.
The rotation of the gear 104b is transmitted to the gear 101b meshed with the gear 104b, and the gear 101b rotates. As the gear 101b rotates, the connecting portion 101a also rotates, whereby the end node portion 101 rotates about the shaft portion 103b.

  Thus, according to the present embodiment, by mounting the drive device ACT capable of outputting low-speed and high-torque rotation, for example, the end node portion 101 can be directly rotated without using a speed reducer. Furthermore, in this embodiment, since the drive device ACT is configured to be driven non-resonantly, most of the configuration can be configured with a lightweight material such as resin. The robot apparatus RBT may be an arm robot or a hand robot used for industrial purposes, or may be a robot used for a service robot.

The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, the example in which both the first transmission member BT1 and the second transmission member BT2 are driven in the direction in which the rotor SF is rotated has been described. However, the present invention is not limited to this. You may drive so that rotation of rotor SF may be suppressed using transmission member BT1 and 2nd transmission member BT2.

  Hereinafter, the aspect of the first embodiment will be described as an example. The controller CONT is, for example, at least one of the first transmission member BT1 and the second transmission member BT2 (for example, for example) in a state where the rotor SF is rotated in the θZ direction by the driving operation and the return operation in the first embodiment. The drive element 131 and the drive element 132 are deformed so that the first end 121 and the second end 122 of the first transmission member BT1 will be described below as an example.

  By this operation, the belt portion 123 of the first transmission member BT1 comes into contact with the rotor SF, and a tension T1 is generated on the first end portion 121 side of the belt portion 123, and the second end portion of the first transmission member BT1. A tension T2 is generated on the 122 side. Accordingly, an effective tension (T1-T2) is generated in the first transmission member BT1. In this state, a frictional force is generated between the belt portion 123 and the rotor SF in the direction opposite to the rotation direction of the rotor SF. The rotation of the rotor SF is restricted by the frictional force.

  In this state, the control unit CONT maintains the state where the effective tension is generated in the first transmission member BT1, and the first end 121 of the first transmission member BT1 moves in the + X direction, and the first The drive element 131 and the drive element 132 are deformed so that the two end portions 122 move in the −X direction.

  In this operation, the control unit CONT makes the moving distance of the first end 121 and the moving distance of the second end 122 equal, for example. With this operation, the first transmission member BT1 moves in the direction opposite to the rotation direction of the rotor SF in a state where a frictional force is generated between the first transmission member BT1 and the rotor SF. For this reason, the rotation of the rotor SF is further restricted.

  Thereafter, the control unit CONT deforms only the drive element 131 so that the second end portion 122 does not move and the first end portion 121 returns to the start position (predetermined position). With this operation, the first end 121 moves in the −X direction, and the first transmission member BT1 is loosely wound. That is, the effective tension applied to the first transmission member BT1 is released. In this state, no frictional force is generated between the first transmission member BT1 and the rotor SF, and the rotation of the rotor SF is not restricted. For this reason, the rotor SF continues to rotate due to inertia.

  After loosening the winding of the first transmission member BT1, the control unit CONT deforms the drive element 132 so that the second end 122 returns to the drive start position (predetermined position). By this operation, the second end 122 of the first transmission member BT1 returns to the driving start position (predetermined position) while the winding of the first transmission member BT1 is loose, that is, the effective tension is not generated. .

  When it is just before the second end 122 is returned to the drive start position, the control unit CONT deforms the drive element 132 and moves the second end 122 in the + X direction. By this operation, the tension T1 is generated on the first end 121 side and the tension T2 is generated on the second end 122 side almost simultaneously with the return of the second end 122 to the drive start position. Thereby, it will be in the state similar to the state (state of FIG. 3) which added effective tension to the 1st transmission member BT1 at the time of a drive start. By repeating this operation, the rotation of the rotor SF is adjusted.

  In addition, when the rotation of the rotor SF is stopped, the control unit CONT brings the belt unit 123 and the rotor SF into a contact state, and drives the drive element 131 and the drive so as to maintain the contact state. The element 132 is deformed. In this case, the rotor SF is in a state in which the rotation is restricted by the static friction force acting between the belt portion 123 and the rotor SF. When rotating the rotor SF, the controller CONT deforms the drive elements 131 and 132 so that the contact state is eliminated. This operation eliminates the restriction on the rotation of the rotor SF. The above operation has been described by taking the first transmission member BT1 as an example, but the same description is possible even when the second transmission member BT2 is used. In the present embodiment, for the above-described operation, the rotation-related information is detected by the detection unit DT, and the operation of the drive unit AC (the first drive unit AC1 and the second drive unit AC2) based on the rotation-related information. Can be controlled.

  Moreover, in the said embodiment, although the surface of the rotor SF was a structure without an unevenness | corrugation, it is not restricted to this, For example, the structure which formed the unevenness | corrugation on the surface of the said rotor SF may be sufficient. For example, as shown in FIG. 17, a rib-like protrusion 60 is formed in the belt hook 11 of the rotor SF. For example, the protrusion 60 is provided side by side so as to provide a space in which the belt portion 123 of the first transmission member BT1 and the belt portion 223 of the second transmission member BT2 are disposed. The belt portions 123 and 223 hung on the rotor SF are positioned by the protruding portion 60 and the flange portion 12.

  A frictional force is generated between the rotor SF and the belt portions 123 and 223, and frictional heat is generated. This frictional heat may affect the torque of the motor device MTR. On the other hand, in the structure shown in FIG. 17, since the protrusion part 60 is each formed in the collar shape, it becomes a structure in which the heat | fever of rotor SF is easy to discharge | release. In this configuration, since the rotor SF can be cooled by air cooling, the rotor SF can be cooled without providing a cooling mechanism or the like. This contributes to miniaturization of the motor device MTR. Thus, the protrusion 60 has a function as a positioning guide mechanism and also has a function as a cooling mechanism for cooling the rotor SF.

  Further, for example, in the above-described embodiment, the rotor SF is a solid (non-hollow shaft) structure, but the present invention is not limited to this. For example, a hollow rotor such as a cylindrical rotor is used. Even when a rotor is used, the present invention can be applied. In this case, for example, the configuration may be such that both ends of the rotor SF are penetrated in the direction of the central axis C by the through holes. For example, when the motor apparatus MTR is mounted on a turning machine such as the robot arm ARM as in the third embodiment, wiring or the like can be arranged inside the cylindrical rotor SF. Of course, the present invention is not limited to the case where the motor device MTR is mounted on the robot arm ARM. In other cases, the rotor SF may be hollow. For example, as shown in FIG. 17, a hollow portion 70 is formed inside the rotor SF. For this reason, the cooling efficiency of the rotor SF is improved.

  When the rotor SF is formed in a hollow shape, for example, the rotor SF may be formed in a cylindrical shape, and the both ends in the central axis direction of the rotor SF may be penetrated. Further, for example, both ends of the rotor SF in the central axis direction are not penetrated, and only one of them can be opened. Further, both ends of the rotor SF in the central axis direction may be closed. Moreover, the structure which makes a hollow inside, arrange | positioning a partition etc. suitably inside the rotor SF may be sufficient.

  Moreover, in the said embodiment, although it was set as the structure by which the belt hook part 11 and the collar part 12 of rotor SF were formed by one member, it is not restricted to this, It is the structure by which these are another members. It does not matter. For example, as shown in FIG. 18, the rotor SF is formed to have a uniform diameter in the direction of the central axis C. A flange member 400 formed in a disk shape, for example, by a metal material is attached to an end portion of the rotor SF using an adhesive layer 401.

  The eaves member 400 is formed, for example, to have substantially the same shape and diameter as the eaves part 12 in the above embodiment. The material constituting the flange member 400 may be, for example, the same material as that constituting the rotor SF, or may be a metal material different from the material constituting the rotor SF. In addition, a light reflection pattern EP similar to that in the above embodiment is formed on the end surface 400a of the flange member 400 opposite to the bonding surface of the rotor SF. Thus, since the flange member 400 and the rotor SF are formed and attached as separate members, the rotor SF can be easily manufactured. Note that an opening may be formed at the center of the flange member 400, and the space on the end surface 400a may be communicated with the hollow portion 70 of the rotor SF. Further, in FIG. 18, the rotor SF is configured to be hollow (cylindrical). However, the configuration is not limited thereto, and a solid configuration may be used.

  Also, a groove may be formed on the surface of the rotor SF. For example, in the configuration shown in FIG. 19A, a plurality of grooves 71 are formed on the surface of the rotor SF. Each groove portion 71 is formed in the circumferential direction of the rotor SF, and is formed side by side in the central axis direction of the rotor SF. For example, the groove portion 71 is formed in a portion of the rotor SF where the belt portion 123 of the first transmission member BT1 and the belt portion 223 of the second transmission member BT2 are hooked.

  In FIG. 19B, for example, when the rotor SF is formed hollow, a plurality of holes 72 are provided in the groove 71 formed on the surface of the rotor SF, and the inside and outside of the rotor SF are holes. A configuration may be adopted in which the units 72 communicate with each other. With this configuration, the friction powder can be guided from the groove portion 71 to the hole portion 72 and escape to the hollow portion 70.

  Moreover, although the said embodiment gave and demonstrated the structure which provided the light reflection pattern EP in the collar part 12 as an example, it is not restricted to this. For example, the light reflection pattern EP may be disposed on the belt hanging portion 11. As shown in FIG. 20, the first transmission member BT1 and the second transmission member BT2 are hung in the direction of the central axis C of the rotor SF, and the light reflection pattern EP is the same as that of the first transmission member BT1. It is provided between the two transmission members BT2.

  In FIG. 20, the protrusion 60 is formed on the belt hook 11 and the light reflection pattern EP is disposed on the protrusion 60. However, the present invention is not limited to this. For example, the light reflection pattern EP may be provided at a position deviated from the protrusion 60. Moreover, even in the case where the protruding portion 60 is not provided, the light reflection pattern EP can be disposed between the first transmission member BT1 and the second transmission member BT2. Note that the optical sensor SR of the detection unit DT is disposed, for example, facing the belt hooking portion 11 so as to face the light reflection pattern EP.

  In the above embodiment, the configuration in which the light reflection pattern EP is exposed to the outside has been described as an example. However, the configuration is not limited thereto, and for example, the configuration in which the light reflection pattern EP is not exposed. It doesn't matter. For example, as shown in FIG. 21, a recess 200 is formed on the end surface 12 a side of the flange 12, and the end surface 12 a is the bottom of the recess 200. For this reason, the light reflection pattern EP is accommodated in the recess 200.

  In this configuration, a cover member CV that closes the recess 200 is further provided. The cover member CV is provided with an insertion portion 201 that is inserted into the recess 200, for example. The end surface 201a of the insertion part 201 is formed so that a gap is left between the light reflection pattern EP and the end surface 201a. An optical sensor SR is embedded in the end surface 201a. The optical sensor SR is directed to the light reflection pattern EP. With such a configuration, for example, dust or oil mist entering from the outside can be prevented, and the environmental resistance is improved.

  Further, for example, as shown in FIG. 22, even if the rotor SF is not provided with the flange portion 12 and the light reflection pattern EP is formed on the outer peripheral surface of the belt hook portion 11 of the rotor SF. The light reflection pattern EP can be covered by the cover portion CV2. The cover part CV <b> 2 has a covering part 300 that covers the outer peripheral surface of the belt hanging part 11. On the inner surface side of the covering portion 300, a protruding portion 301 protruding toward the light reflection pattern EP is formed. For example, the protrusion 301 is formed so that a gap is left between the protrusion 301 and the light reflection pattern EP. An optical sensor SR is embedded on the inner surface side of the protruding portion 301. The optical sensor SR is directed to the light reflection pattern EP. Even with such a configuration, for example, dust or oil mist entering from the outside can be prevented, and the environmental resistance is improved.

  In the above description, the reflection type optical detector that detects the reflected light of the detection light is used as the optical sensor SR. However, the present invention is not limited to this, and other types of optical detectors are used. It doesn't matter. Further, the optical sensor SR may be arranged directly on the flange 12 (or the disc member 100). Further, a configuration may be adopted in which a plurality of optical sensors SR are positioned. In this case, for example, it may be configured to be disposed at both ends of the rotor SF.

  Further, in addition to the configuration of the above-described embodiment, for example, a configuration in which a tension detection unit that detects the tension of the belt portions 123 and 223 of the first transmission member BT1 and the second transmission member BT2 may be provided. The tension detector can be provided in the vicinity of the first end portions 121 and 221 of the belt portions 123 and 223, for example. For example, a strain gauge can be used as the tension detecting unit. Of course, other tension detecting elements can be used. The tension detection unit is configured such that the detection signal is, for example, a control unit CONT. The control unit CONT is configured to control, for example, the first drive unit AC1 and the second drive unit AC2 based on the detection signal. By detecting the tension of the first transmission member BT1 and the second transmission member BT2, it is possible to detect whether or not the motor device MTR is generating torque.

  Further, for example, in each of the above embodiments, the case where the pair of the drive unit AC and the transmission member BT is provided has been described as an example, but the present invention is not limited thereto, and for example, the drive unit AC and the transmission member BT. It may be a configuration in which only one phase is provided. Further, even when a plurality of sets of the drive unit AC and the transmission member BT are provided, only one of them may be driven. Moreover, you may make it provide 3 or more sets of drive part AC and transmission member BT. When the drive unit AC and the transmission member BT are arranged in a plurality of phases, the drive unit AC and the transmission member BT can be arranged at positions shifted from each other at an equal pitch, for example. In this case, the drive unit AC and the transmission member BT can be sequentially driven for each phase.

  Moreover, although the said embodiment demonstrated and demonstrated the structure in which base part BS was formed in the rectangle by the front view, it is not restricted to this, Other shapes may be sufficient. For example, it may be a circle or an ellipse, or may be another polygon such as a trapezoid, a parallelogram, a diamond, a triangle, a pentagon, or a hexagon.

  Further, as the shape of the belt portions 123 and 223, in the above-described embodiment, the belt portions 123 and 223 formed in a belt shape have been described as examples. However, the belt portions 123 and 223 are not limited to this, and are, for example, linear or chain-like. Other shapes may be used.

  MTR, MTR3 ... Motor device BS ... Base portion SF ... Rotor AC ... Drive portion BT ... Transmission member DT ... Detection portion EP ... Light reflection pattern SR ... Optical sensor RBT ... Robot device ACT ... Drive device ARM ... Robot arm AC1 ... No. One drive part CONT ... Control part

Claims (15)

A rotor,
A transmission section hung on at least a part of the outer periphery of the rotor;
A drive unit that moves the transmission unit a fixed distance between the rotor and the transmission unit in a rotational force transmission state, and returns the transmission unit to a predetermined position in a state in which the rotational force transmission state is eliminated;
With
A part of the rotor also serves as a part of a detection unit that detects information related to rotation of the rotor. The detection unit has a pattern that moves as the rotor rotates.
The motor device according to claim 1, wherein the pattern is provided on the rotor. The motor device according to claim 2, wherein the pattern is formed along a rotation direction of the rotor. The motor device according to claim 2, wherein the pattern is provided on the outer periphery. The motor device according to any one of claims 2 to 4, wherein the pattern is provided on an end surface of the rotor. The rotor has a collar portion formed along the circumferential direction on the outer periphery,
The motor device according to any one of claims 2 to 5, wherein the pattern is provided on the flange portion. The rotor has a cooling mechanism for cooling the transmission unit,
The motor device according to claim 6, wherein the flange portion also serves as the cooling mechanism. The rotor has a protrusion formed on the outer periphery to guide the transmission unit,
The motor device according to claim 2, wherein the pattern is provided on the protruding portion. A plurality of the transmission parts are hung at intervals in the rotation axis direction of the rotor,
The motor device according to any one of claims 2 to 8, wherein the pattern is disposed between the plurality of transmission units. The detection unit has a disk member on which a pattern that moves as the rotor rotates is formed,
The motor device according to claim 1, wherein the disk member is disposed on the rotor. The motor device according to any one of claims 2 to 10, wherein the detection unit includes a cover unit that covers the pattern. The motor device according to claim 11, wherein the cover portion is formed as a part of the rotor. The detector has a pattern detector for detecting the pattern,
The motor device according to any one of claims 2 to 12, wherein the pattern detector is disposed with a gap between the pattern detector and the pattern. Moving the transmission part by a certain distance in a rotational force transmission state between the rotor and the transmission part hung on the rotor;
Returning the transmission unit to a predetermined position in a state in which the rotational force transmission state is eliminated;
Detecting information related to rotation of the rotor using a part of the rotor that also serves as a part of a detection unit that detects information related to rotation of the rotor. Driving method. A rotating shaft member;
A motor device for rotating the rotating shaft member,
The motor apparatus as described in any one of Claims 1-13 is used as the said motor apparatus. The robot apparatus.

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