JP4941075B2 - Vibration actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vibration actuator to transmit power between a stator side and a rotor side, or establish communication between them without using a wiring cable. <P>SOLUTION: When an AC current of a prescribed frequency is made to flow to a coil 12 in a stator 2 by a power feed circuit 13, a magnetic field which changes is generated around the coil 12, the magnetic field line M passes through the rotor 6 from the coil 12 via a step 11 of the stator 2, then enters the stator 2 again from a step 11 at an opposite side and returns to the coil 12. The magnetic field line M passes through a coil 14 embedded in the rotor 6, so that an electromotive force is induced at the coil 14 and power is fed to a power using circuit 15 connected to the coil 14. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a vibration actuator, and more particularly to a vibration actuator that performs power transmission and / or communication between a stator side and a rotor side.

In recent years, a vibration actuator for rotating a rotor using ultrasonic vibration has been proposed and put into practical use. This vibration actuator generates a traveling wave on the surface of a stator using a piezoelectric element, and moves the rotor through frictional force between the two by bringing the rotor into pressure contact with the stator. .
For example, Patent Literature 1 discloses a vibration actuator that rotates a rotor by bringing a stator into pressure contact with the surface of a spherical rotor from four directions and generating vibration in each stator. This vibration actuator can be used as an intelligent eye by embedding a small camera in the rotor. The video imaged by the small camera is sent to a camera control unit arranged outside the vibration actuator via a wiring cable connected to the small camera.

Japanese Patent Laid-Open No. 9-54356

However, since the video cable is taken out by connecting the wiring cable to the small camera embedded in the rotor, the tension of the wiring cable affects the movement of the rotor, and the accuracy of the rotation control of the rotor decreases, There is a risk of disconnection of the wiring cable. Moreover, the problem that the installation space of a wiring cable is needed will also arise.
The present invention has been made to solve such a problem, and provides a vibration actuator capable of performing power transmission and / or communication between a stator side and a rotor side without using a wiring cable. For the purpose.

The vibration actuator according to the present invention is a vibration actuator that rotates a rotor by generating vibration in the stator in a state where the rotor is pressurized against the stator, and is arranged on each of the stator side and the rotor side. And a stator-side transmission means and a rotor-side transmission means for transmitting electrical energy in a non-contact manner, the stator-side transmission means including at least one coil, and the rotor-side transmission means are in different directions. The plurality of coils included in the rotor side transmission means are arranged so that a part thereof passes near the rotation center of the rotor, and these stator side transmission means and rotor side transmission It means by performing the transmission of electrical energy by electromagnetic induction, in which divided power transmission line between the stator side and the rotor side.
Here, the stator side includes not only the stator but also other members fixed to the stator. Further, the rotor side includes not only the rotor but also other members that are fixed to the rotor and move together with the rotor.

Incidentally, the stator and rotor are preferably formed of a magnetic material.

Ru can be used vibration actuator of this to the robot hand.

According to the present invention, since it provided the respective stator side transmitting means and the rotor-side transmitting means to the stator side and rotor side, feed in between the stator side and rotor side without using a wire cable electric it is possible to perform.
Since the transmission of electrical energy between the driving of the vibration actuator for rotating the rotor stator side transmitting means and the rotor-side transfer means by the vibration are those less likely to interfere with each other, and electricity transmission and driving of the vibration actuator Can be performed independently without affecting each other.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
Embodiment 1
FIG. 1 shows a vibration actuator according to Embodiment 1 of the present invention. A vibrating body 3 is sandwiched between the base 1 and the stator 2, and the base 1 and the stator 2 are connected to each other via a connecting bolt 4 that is passed through the vibrating body 3. A concave portion 5 is formed on the stator 2 on the side opposite to the surface in contact with the vibrating body 3, and a substantially lower half portion of a substantially spherical rotor 6 is accommodated in the concave portion 5. A movable portion 7 is fixed to the rotor 6, and the movable portion 7 and the stator 2 are movably connected to each other by a flexible holding member 8. The stator 2 and the rotor 6 are each made of a magnetic material.
Here, for convenience of explanation, the Z-axis extends from the base 1 toward the rotor 6, the X-axis extends in a direction perpendicular to the Z-axis, and the Y-axis extends in a direction perpendicular to the Z-axis and the X-axis. Shall.

  The concave portion 5 of the stator 2 includes a small-diameter portion 9 having an inner diameter smaller than the diameter of the rotor 6 and a large-diameter portion 10 having an inner diameter larger than the diameter of the rotor 6, and the small-diameter portion 9 and the large-diameter portion 10. An annular step 11 located on the XY plane is formed at the boundary between the two. The rotor 6 is rotatably supported in contact with the step 11 in the recess 5. Further, the rotor 6 is brought into pressure contact with the step 11 of the stator 2 by a holding member 8 that couples the movable portion 7 and the stator 2.

  In the stator 2, a coil 12 as a stator-side transmission means is embedded immediately below the recess 5, and a power supply circuit 13 is electrically connected to the coil 12. On the other hand, in the rotor 6, a coil 14 as a rotor-side transmission means is embedded near the rotation center of the rotor 6, and a power utilization circuit 15 is electrically connected to the coil 14. The coil 14 is disposed at a position such that a part thereof passes through the rotation center of the rotor 6. The power usage circuit 15 is an electrical device that performs some operation using supplied power. For example, an electric motor disposed in the movable portion 7 can be used as the power usage circuit 15.

  The vibrating body 3 is for generating ultrasonic vibrations in the stator 2 to rotate the rotor 6 about three axes of X, Y, and Z, respectively, and is positioned on the XY plane and overlapped with each other. Plate-shaped first to third piezoelectric element portions 31 to 33 are provided. These first to third piezoelectric element portions 31 to 33 are electrically connected to the drive circuit 16, respectively.

  Specifically, as shown in FIG. 2, the first piezoelectric element portion 31 includes an electrode plate 31a, a piezoelectric element plate 31b, an electrode plate 31c, a piezoelectric element plate 31d, and an electrode plate 31e each having a disk shape. It has a structure that is sequentially stacked. Similarly, the second piezoelectric element portion 32 has a structure in which an electrode plate 32a, a piezoelectric element plate 32b, an electrode plate 32c, a piezoelectric element plate 32d, and an electrode plate 32e each having a disk shape are sequentially stacked. 3 has a structure in which an electrode plate 33a, a piezoelectric element plate 33b, an electrode plate 33c, a piezoelectric element plate 33d, and an electrode plate 33e each having a disk shape are sequentially stacked. These piezoelectric element portions 31 to 33 are arranged in a state of being insulated from the stator 2 and the base portion 1 through insulating sheets 34 to 37 and from each other.

As shown in FIG. 3, the pair of piezoelectric element plates 31 b and 31 d of the first piezoelectric element portion 31 have portions that are divided into two in the Y-axis direction and have opposite polarities, and each has a Z-axis direction (thickness direction). The piezoelectric element plate 31b and the piezoelectric element plate 31d are disposed so as to be reversed with respect to each other.
The pair of piezoelectric element plates 32b and 32d of the second piezoelectric element portion 32 are polarized so as to be expanded or contracted in the Z-axis direction (thickness direction) as a whole without being divided into two. The element plate 32b and the piezoelectric element plate 32d are arranged inside out.
In the pair of piezoelectric element plates 33b and 33d of the third piezoelectric element portion 33, the portions divided into two in the X-axis direction have opposite polarities, and are opposite to expansion and contraction in the Z-axis direction (thickness direction), respectively. The piezoelectric element plate 33b and the piezoelectric element plate 33d are disposed so as to be reversed with respect to each other.

  An electrode plate 31a and an electrode plate 31e disposed on both surface portions of the first piezoelectric element portion 31, an electrode plate 32a and an electrode plate 32e disposed on both surface portions of the second piezoelectric element portion 32, and a third The electrode plate 33a and the electrode plate 33e disposed on both surface portions of the piezoelectric element portion 33 are electrically grounded. Further, the electrode plate 31 c disposed between the pair of piezoelectric element plates 31 b and 31 d of the first piezoelectric element portion 31 and the pair of piezoelectric element plates 32 b and 32 d of the second piezoelectric element portion 32 are disposed. The electrode plate 32c disposed between the pair of piezoelectric element plates 33b and 33d of the third piezoelectric element portion 33 is electrically connected to the drive circuit 16, respectively.

Next, the operation of the vibration actuator according to the first embodiment will be described.
When an alternating voltage having a frequency close to the natural frequency of the vibration actuator is applied to the vibrating body 3 to the electrode plate 31c of the first piezoelectric element portion 31, a pair of piezoelectric element plates 31b of the first piezoelectric element portion 31 and The two parts 31d are alternately expanded and contracted in the Z-axis direction, and the stator 2 generates a flexural vibration in the Y-axis direction. Similarly, when an AC voltage is applied to the electrode plate 32c of the second piezoelectric element portion 32, the pair of piezoelectric element plates 32b and 32d of the second piezoelectric element portion 32 repeats expansion and contraction in the Z-axis direction, and the stator 2 generates longitudinal vibration in the Z-axis direction. Further, when an AC voltage is applied to the electrode plate 33c of the third piezoelectric element portion 33, the two divided portions of the pair of piezoelectric element plates 33b and 33d of the third piezoelectric element portion 33 expand and contract in the Z-axis direction. Are alternately repeated to generate a flexural vibration in the X-axis direction in the stator 2.

Therefore, for example, when an AC voltage having a phase shifted by 90 degrees is applied from the drive circuit 16 to both the electrode plate 32c of the second piezoelectric element portion 32 and the electrode plate 33c of the third piezoelectric element portion 33, X An elliptical vibration in the XZ plane is generated in the step 11 of the stator 2 in contact with the rotor 6 by combining the axial flexural vibration and the vertical vibration in the Z-axis direction. Rotate around the axis.
Similarly, when an AC voltage whose phase is shifted by 90 degrees is applied from the drive circuit 16 to both the electrode plate 31c of the first piezoelectric element section 31 and the electrode plate 32c of the second piezoelectric element section 32, respectively, the Y axis Direction vibration and Z-axis longitudinal vibration are combined to generate elliptical vibration in the YZ plane at the step 11 of the stator 2 in contact with the rotor 6, and the rotor 6 is moved to the X-axis via frictional force. Rotate around.
Further, when an AC voltage having a phase shifted by 90 degrees is applied from the drive circuit 16 to both the electrode plate 31c of the first piezoelectric element portion 31 and the electrode plate 33c of the third piezoelectric element portion 33, the X-axis direction In this way, elliptical vibration in the XY plane is generated at the step 11 of the stator 2 that comes into contact with the rotor 6 by combining the flexural vibration in the Y-axis direction and the flexural vibration in the Y-axis direction, and the rotor 6 rotates about the Z-axis through frictional force. Rotate to.
By driving the vibrating body 3 in this way, the rotor 6 rotates around the three axes of X, Y, and Z, and the movable portion 7 moves accordingly.

  Here, when an alternating current or pulse current of a predetermined frequency is passed through the coil 12 in the stator 2 by the power supply circuit 13, a magnetic field that changes around the coil 12 is generated. However, both the stator 2 and the rotor 6 are Since they are made of a magnetic material and are in contact with each other via a step 11, as shown in FIG. 1, the step 12 on the opposite side passes from the coil 12 through the step 11 of the stator 2 through the rotor 6. Then, a magnetic field line M is formed which again enters the stator 2 and returns to the coil 12. When the magnetic force lines M pass through the coil 14 embedded in the rotor 6, an electromotive force is induced in the coil 14, and power is supplied to the power utilization circuit 15 connected to the coil 14. In this manner, the coil 12 in the stator 2 and the coil 14 in the rotor 6 are electromagnetically coupled to each other, and electrical energy is transmitted between these coils 12 and 14, so that the stator can be used without using a wiring cable. It is possible to perform power transmission from the 2 side to the rotor 6 side.

  Since the wiring cable is not connected to the rotor 6, the tension of the wiring cable does not affect the rotation of the rotor 6, and the rotation control accuracy of the rotor 6 is reduced, or the wiring cable is disconnected. The possibility of power transmission becoming impossible is avoided. In addition, a space for installing the wiring cable is not required, and a small vibration actuator is realized.

  As described above, in this vibration actuator, since the rotor 6 contacts the step 11 of the stator 2 and is driven to rotate by vibration, electric energy is transmitted and vibrated by electromagnetic coupling of the coils 12 and 14. The actuator drive is less likely to interfere with each other. For this reason, driving of the vibration actuator and power supply can be performed independently without affecting each other. Further, since a part of the coil 14 is embedded at a position passing through the rotation center of the rotor 6, as shown in FIG. 4, even if the rotor 6 rotates as the vibration actuator is driven. The position of the coil 14 with respect to the stator 2 hardly changes, so that stable power can be supplied regardless of the rotation of the rotor 6.

  In general, the magnetic field lines have a property that it is easy to pass through the magnetic body and difficult to pass through the non-magnetic body. Therefore, by arranging the non-magnetic body at appropriate portions of the stator 2 and the rotor 6, The range of the magnetic lines of force M formed by the coil 12 is restricted, and it becomes possible to efficiently transmit electrical energy between the coil 12 in the stator 2 and the coil 14 in the rotor 6. For example, a non-magnetic material such as a resin material may be disposed on the surface of the rotor 6 where it does not come into contact with the step 11 of the stator 2 even when the rotor 6 rotates as the vibration actuator is driven. it can.

Embodiment 2
In the first embodiment, one coil 14 is embedded in the rotor 6 as the rotor-side transmission means. However, a plurality of coils facing different directions are embedded in the vicinity of the rotation center in the rotor 6. The plurality of coils can be connected to each other. For example, as shown in FIG. 5, a coil 14x facing the X-axis direction, a coil 14y facing the Y-axis direction, and a coil 14z facing the Z-axis direction are embedded in the rotor 6 and are mutually connected. What was connected in series can be used as a rotor side transmission means. The coils 14x, 14y, and 14z are arranged at positions such that a part thereof passes near the rotation center in the rotor 6.

  If such a rotor-side transmission means is used, even if the rotation angle of the rotor 6 increases as the vibration actuator is driven, the magnetic field lines M formed by the coils 12 in the stator 2 become the coils 14x, It becomes easy to penetrate at least one of 14y and 14z, and more stable power supply is possible.

Embodiment 3
FIG. 6 shows a vibration actuator according to the third embodiment. In the third embodiment, in the vibration actuator according to the first embodiment shown in FIG. 1, the diameter is slightly inside the outer peripheral portion of the rotor 6 instead of embedding the coil 14 near the rotation center in the rotor 6. A large coil 17 is embedded, and this is used as a rotor side transmission means. The coil 17 has a diameter slightly smaller than the diameter of the rotor 6 on the cut surface including one diameter of the substantially spherical rotor 6, and the center of the coil 17 is substantially the same as the rotation center of the rotor 6. They are arranged to match.

If the coil 17 having such a large diameter is used, even if the rotation angle of the rotor 6 increases as the vibration actuator is driven, the magnetic lines of force M formed by the coil 12 in the stator 2 It becomes easy to penetrate and stable power supply becomes possible.
A plurality of coils 17 having a large diameter can be embedded in the rotor 6 in different directions.

Embodiment 4
FIG. 7 shows a vibration actuator according to the fourth embodiment. In the fourth embodiment, in the vibration actuator according to the first embodiment shown in FIG. 1, instead of embedding the coil 12 immediately below the concave portion 5 of the stator 2, the fixing is located on both sides of the opposing concave portion 5. Coils 12a and 12b are respectively embedded in the child 2, and these coils 12a and 12b are connected to each other to form a stator side transmission means.

By passing an alternating current or a pulse current from the power supply circuit (not shown) to the coils 12a and 12b, the coil 12b passes through the rotor 6 through the step 11 of the stator 2 and passes through the rotor 6 as in the first embodiment. Magnetic field lines M are formed from the step 11 again into the stator 2, passing through the coil 12 a, and returning to the coil 12 b. For this reason, the coils 12a and 12b in the stator 2 and the coil 14 in the rotor 6 are electromagnetically coupled to each other, and electrical energy is transmitted between these coils 12a, 12b and the coil 14, and the stator 2 It is possible to perform power transmission from the side to the rotor 6 side.
Thus, if a plurality of coils are used as the stator side transmission means, it is easy to form the magnetic lines of force M at a desired position, and more stable power transmission is possible.
Note that three or more coils may be embedded in the stator 2, and these coils may be connected to each other to serve as the stator-side transmission means. In addition, it is possible to switch the connection of a plurality of coils embedded in the stator 2, and a coil that can transmit electrical energy with high sensitivity between the plurality of coils and the coil 14 in the rotor 6. Two or more can be selected and used as the stator side transmission means.

Embodiment 5
FIG. 8 shows a vibration actuator according to the fifth embodiment. The fifth embodiment uses a stator 18 formed of a metal as an electric conductor instead of the stator 2 formed of a magnetic material in the vibration actuator of the first embodiment shown in FIG. Instead of the coil 12, the antenna 23 is used as a stator side transmission means, and instead of the coil 14, an antenna 24 is used as a rotor side transmission means.

A concave portion 19 is formed on the stator 18 on the side opposite to the surface in contact with the vibrating body 3. The concave portion 19 includes a small diameter portion 20 having an inner diameter smaller than the diameter of the rotor 6 and a large diameter portion 21 having an inner diameter larger than the diameter of the rotor 6, and a boundary between the small diameter portion 20 and the large diameter portion 21. An annular step 22 located on the XY plane is formed in the part. The rotor 6 is rotatably supported while being in contact with the step 22 in the recess 19, and the rotor 6 is supported with respect to the step 22 of the stator 18 by the holding member 8 that connects the movable portion 7 and the stator 18. Pressure contact.
An antenna 23 is disposed in the recess 19 of the stator 18 and below the rotor 6, and the power supply circuit 13 is electrically connected to the antenna 23. An antenna 24 is embedded in the vicinity of the rotation center of the rotor 6, and the power utilization circuit 15 is electrically connected to the antenna 24.

  Similarly to the first embodiment, the stator 18 is driven by selectively applying an AC voltage from the drive circuit 16 to the first to third piezoelectric element portions 31 to 33 of the vibrating body 3 to drive the vibrating body 3. Elliptical vibration is generated in the step 22, and the rotor 6 rotates around the three axes of X, Y, and Z, and the movable portion 7 moves accordingly.

  Here, when an alternating current or a pulse current having a predetermined frequency is passed through the antenna 23 in the stator 18 by the power supply circuit 13, a radio wave that is one type of electromagnetic wave is transmitted from the antenna 23. The antenna 24 in the rotor 6 receives this radio wave to generate an electromotive force, and power is supplied to the power utilization circuit 15 connected to the antenna 24. In this way, electrical energy is transmitted between the antenna 23 in the stator 18 and the antenna 24 in the rotor 6, and power is transmitted from the stator 18 side to the rotor 6 side without using a wiring cable. Can be done.

As in the first embodiment, since the transmission of electrical energy between the antennas 23 and 24 and the driving of the vibration actuator are difficult to interfere with each other, the driving of the vibration actuator and the supply of power are performed. It becomes possible to carry out independently without affecting each other.
As shown in FIG. 8, since the antennas 23 and 24 are substantially surrounded by the stator 18 made of metal, the stator 18 exhibits a shielding effect against transmission and reception of radio waves. Stable radio wave transmission / reception can be performed by reducing the influence of disturbance between the antennas 23 and 24.
Further, since the antenna 24 is embedded in the vicinity of the rotation center of the rotor 6, the position of the antenna 24 with respect to the stator 18 hardly changes even when the rotor 6 rotates as the vibration actuator is driven. For this reason, it is possible to supply stable power regardless of the rotation of the rotor 6.
Although the stator 18 is made of metal, a shielding effect can be obtained against transmission and reception of radio waves even when a hard resin surface is coated with a conductive material by plating or the like.

Embodiment 6
FIG. 9 shows a vibration actuator according to the sixth embodiment. In this sixth embodiment, in the vibration actuator of the fifth embodiment shown in FIG. 8, instead of the rotor 6 and the movable portion 7, a rotor 25 and a movable portion 26 both made of metal are used, and an antenna 24 is used. Is arranged inside the movable portion 26.

  The movable portion 26 is fixed to the rotor 25 and has a cavity 27 inside, and the antenna 24 is disposed in the cavity 27. On the other hand, the rotor 25 is rotatably supported in contact with the step 22 of the stator 18, and has a through hole 28 that communicates with both the cavity 27 of the movable portion 26 and the recess 19 of the stator 18. is doing. The antenna 23 disposed in the concave portion 19 of the stator 18 and the antenna 24 disposed in the cavity 27 of the movable portion 26 face each other through the through hole 28 of the rotor 25.

Even with such a configuration, it is possible to transmit power from the stator 18 side to the rotor 25 side by transmitting and receiving radio waves between the antennas 23 and 24.
In addition, since the stator 18, the rotor 25, and the movable part 26, each formed of metal, exhibit a shielding effect, the influence of disturbance is reduced, and stable transmission / reception of radio waves between the antennas 23 and 24 can be performed. it can.
Further, even if the rotor 25 rotates as the vibration actuator is driven, the distance between the antennas 23 and 24 hardly changes, so that stable power can be supplied regardless of the rotation of the rotor 25. It becomes possible.
Although the rotor 25 and the movable portion 26 are made of metal, a shield effect can be obtained against transmission and reception of radio waves even when a hard resin surface is coated with a conductive material by plating or the like.

Embodiment 7
FIG. 10 shows a vibration actuator according to the seventh embodiment. In the vibration actuator according to the first embodiment shown in FIG. 1, the seventh embodiment has a power supply circuit 13 connected to the coil 12 on the stator 2 side and a power utilization circuit 15 on the coil 14 on the rotor 6 side. Instead of connecting, the power utilization circuit 15 is connected to the coil 12 on the stator 2 side, and the power supply circuit 13 is connected to the coil 14 on the rotor 6 side.

As the power supply circuit 13, for example, a power generation unit such as a solar cell mounted on the movable portion 7 can be used.
As in the first embodiment, by transmitting electrical energy between the coils 12 and 14, power can be transmitted from the rotor 6 side including the movable portion 7 to the stator 2 side.
Similarly, also in Embodiments 2 to 6, power can be supplied from the rotor 6 side to the stator 2 side by exchanging the power supply circuit 13 and the power use circuit 15 with each other.

Embodiment 8
FIG. 11 shows a vibration actuator according to the eighth embodiment. In the vibration actuator according to the first embodiment shown in FIG. 1, the power supply circuit 13 is connected to the coil 12 on the stator 2 side and the power utilization circuit 15 is connected to the coil 14 on the rotor 6 side. Instead of connection, communication circuits 41 and 42 are connected to the coils 12 and 14, respectively, so that communication is performed between the stator 2 side and the rotor 6 side.

  When an electrical signal having a predetermined frequency is supplied from the communication circuit 41 on the stator 2 side to the coil 12 in the stator 2, electrical energy is transmitted between the coil 12 and the coil 14 in the rotor 6, and rotation is performed. An electrical signal is sent from the coil 14 in the child 6 to the communication circuit 42. Conversely, when an electrical signal having a predetermined frequency is passed from the communication circuit 42 on the rotor 6 side to the coil 14 in the rotor 6, electrical energy is transmitted between the coil 14 and the coil 12 in the stator 2. Then, an electrical signal is sent from the coil 12 in the stator 2 to the communication circuit 41.

  In this manner, electrical signals such as control signals and data signals can be transmitted and received by performing communication between the stator 2 side and the rotor 6 side without using a wiring cable. For example, a sensor that detects a predetermined physical quantity is mounted on the movable portion 7, and a detection signal from this sensor is sent from the communication circuit 42 to the coil 14 in the rotor 6, and communication is performed via the coil 12 on the stator 2 side. Transmission to the circuit 41 becomes possible. Similarly, a control signal can be transmitted from the communication circuit 41 on the stator 2 side to the communication circuit 42 on the rotor 6 side to control operations of various devices attached to the movable portion 7.

Since the transmission of electrical energy between the coils 12 and 14 and the drive of the vibration actuator are difficult to interfere with each other, the drive and communication of the vibration actuator are performed independently without affecting each other. Is possible.
In addition, both the communication circuit and the power supply circuit are connected to one of the coil 12 on the stator 2 side and the coil 14 on the rotor 6 side, and both the communication circuit and the power utilization circuit are connected to the other side. It can also be configured to perform power transmission together. If communication and power transmission use different frequencies, communication and power transmission can be performed simultaneously.
Similarly, in the second to sixth embodiments, communication can be performed between the stator 2 side and the rotor 6 side, and it is also possible to perform both communication and power transmission.

The vibration actuator according to the present invention can be used for a robot hand of a self-propelled robot, for example. The robot hand shown in FIG. 12 has the movable portion 7 of the vibration actuator V of the first embodiment as the first node, and the second node 43 and the third node 44 are sequentially connected in series to the movable portion 7, and these movable portions are connected. 7, the second section 43 and the third section 44 constitute a finger portion.
The movable portion 7 and the second node 43 are connected to each other via a connection mechanism (not shown), and the second node 43 and the third node 44 are also connected to each other via a connection mechanism (not shown). Thus, the movable portion 7, the second joint 43, and the third joint 44 are each configured to perform a predetermined movement.
Similarly, a robot hand can be configured using the vibration actuators of the second to eighth embodiments.

  It is possible to mount a power utilization circuit having an electric motor or the like on the third section 44 corresponding to the fingertip and drive the power utilization circuit of the third section 44 by transmitting power from the stator 2 side to the rotor 6 side. Become. Further, a sensor is mounted on the third node 44, and a detection signal from this sensor can be transmitted from the rotor 6 side to the stator 2 side.

  In the above first to eighth embodiments, the rotor 6 or 25 is rotated around the three rotation axes of X, Y, and Z using the first to third piezoelectric element portions 31 to 33. However, the present invention is not limited to this, and the present invention can also be applied to a vibration actuator that rotates only around one rotation axis or only around two rotation axes. In the case of rotating only around one rotation axis, the rotor does not need to be substantially spherical, and may be, for example, a cylindrical shape.

It is sectional drawing which shows the vibration actuator which concerns on Embodiment 1 of this invention. 3 is a partial cross-sectional view illustrating a configuration of a vibrating body used in Embodiment 1. FIG. 3 is a perspective view showing polarization directions of three pairs of piezoelectric element plates of a vibrating body used in Embodiment 1. FIG. FIG. 3 is a cross-sectional view showing a state where the rotor is rotated in the first embodiment. 6 is a perspective view showing a rotor used in Embodiment 2. FIG. FIG. 6 is a cross-sectional view showing a vibration actuator according to a third embodiment. FIG. 6 is a cross-sectional view showing a vibration actuator according to a fourth embodiment. FIG. 10 is a cross-sectional view showing a vibration actuator according to a fifth embodiment. FIG. 10 is a cross-sectional view showing a vibration actuator according to a sixth embodiment. FIG. 10 is a cross-sectional view showing a vibration actuator according to a seventh embodiment. FIG. 10 is a sectional view showing a vibration actuator according to an eighth embodiment. FIG. 3 is a perspective view showing a robot hand using the vibration actuator according to the first embodiment.

Explanation of symbols

  1 base, 2,18 stator, 3 vibrator, 4 connecting bolt, 5,19 recess, 6,25 rotor, 7,26 movable part, 8 holding member, 9,20 small diameter part, 10,21 large diameter part 11, 22 steps, 12, 12 a, 12 b, 14, 14 x, 14 y, 14 z, 17 coil, 13 power supply circuit, 15 power utilization circuit, 16 drive circuit, 23, 24 antenna, 27 cavity, 28 through hole, 31 1st piezoelectric element part, 32 2nd piezoelectric element part, 33 3rd piezoelectric element part, 41, 42 communication circuit, 43 2nd section, 44 3rd section, M magnetic field line, V vibration actuator.

Claims (3)

In a vibration actuator that rotates the rotor by generating vibration in the stator in a state where the rotor is pressurized against the stator,
A stator-side transmission means and a rotor-side transmission means that are arranged on the stator side and the rotor side, respectively, and transmit electric energy in a non-contact manner;
The stator side transmission means includes at least one coil,
The rotor side transmission means includes a plurality of coils oriented in different directions,
The plurality of coils included in the rotor-side transmission means are arranged so that a part thereof passes near the rotation center of the rotor,
Vibrating said stator-side transmission unit and said rotor-side transfer means by performing the transmission of electrical energy by electromagnetic induction, power transmission between the rotor side to the stator side, characterized in that the dividing line Actuator. The vibration actuator according to claim 1 , wherein the stator and the rotor are formed of a magnetic material. Vibration actuator according to claim 1 or 2 used in the robot hand.

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