KR20090064573A - Object handling device - Google Patents

Abstract

A current is supplied from a drive control section (T) to the piezoelectric element means (3) of a vibration actuator (A) and a rotor (4) is rotated thus handling an object by means of a joint mechanism. To grasp the object by the joint mechanism and sustain such state, current supply from the drive control section (T) to the piezoelectric element means (3) is stopped and rotation of the rotor (4) for the stator (2) is prevented by static torque, thus sustaining a state where the object (M) is grasped by the joint mechanism. When current supply is stopped, the drive control section (T) detects stress and temperature by measuring the voltage of each piezoelectric element plate in the piezoelectric element means (3) and when a stress more than a predetermined value is detected, the drive control section (T) supplies a current to the piezoelectric element means (3) such that the state of the joint mechanism at that time is sustained and drives the vibration actuator (A).

Description

Object handling device {OBJECT HANDLING DEVICE}

The present invention relates to an object handling apparatus, and more particularly, to an object handling apparatus such as a robot hand for gripping or moving an object.

In recent years, object handling apparatuses, such as a robot hand which can handle handling, such as holding an object or moving, are known.

For example, the robot hand disclosed in Patent Document 1 has a motor as a drive source, and the rotational force of the motor is transmitted to a plurality of joints through a wire to be driven, whereby the finger can be bent and the object can be gripped.

(Patent Document 1) Japanese Unexamined Patent Publication No. 2001-277174

Problems to be Solved by the Invention

In general, however, in general-purpose motors, it is often impossible to maintain a stop on the rotating shaft when the energization is stopped. Therefore, when the robot hand of Patent Literature 1 grips an object to maintain the state, the motor is continuously energized. It is necessary to increase the energy consumption.

In addition, when power supply to the motor is stopped due to a power failure or the like, the holding force of the robot hand is lowered, and there is a fear that an object may fall from the robot hand.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to provide an object handling apparatus capable of continuously maintaining a handling state for an object even without energizing a drive source.

Means to solve the problem

An object handling apparatus according to the present invention includes a stator, a rotor in pressure contact with the stator by a preloading means, a vibration actuator having piezoelectric element means connected to the stator, and a piezoelectric element means to rotate the rotor by vibrating the stator. And a drive control section for handling the object, and at the time of stopping the energization of the piezoelectric element means, the rotation of the rotor is prevented by the pressurization by the preloading means to maintain the handling state of the rotor with respect to the object. The rotor detects the stress applied to the piezoelectric element means by measuring the voltage of the piezoelectric element means when the energization of the piezoelectric element means stops, and when detecting a stress higher than or equal to a predetermined value, the rotor torque is supplied to the rotor by energizing the piezoelectric element means. To maintain the handling of the rotor object.

Effects of the Invention

According to the present invention, the handling state with respect to an object can be maintained continuously, without energizing a drive source.

1 is a partially broken perspective view showing an object handling apparatus according to an embodiment of the present invention.

It is sectional drawing which shows the vibration actuator and drive control part in embodiment.

3 is a partial cross-sectional view showing the configuration of piezoelectric element means used in the embodiment.

4 is a perspective view showing the polarization direction of three pairs of piezoelectric element plates of the piezoelectric element means used in the embodiment.

5 is a perspective view illustrating a configuration of a first piezoelectric element portion in an embodiment.

6 is a perspective view illustrating a configuration of a second piezoelectric element portion in the embodiment.

7 is a perspective view showing a state in which an object is gripped by the object handling apparatus according to the embodiment of the present invention.

It is sectional drawing which shows the vibration actuator and drive control part in other embodiment of this invention.

Best Mode for Carrying Out the Invention

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described based on an accompanying drawing.

FIG. 1: shows the perspective view which broke part of the object handling apparatus which concerns on embodiment of this invention. This object handling apparatus comprises one finger of a robot hand, for example, and has the vibration actuator A as a drive source. In this vibrating actuator A, the piezoelectric element means 3 is arranged between the base block 1 and the stator 2, and the spherical rotor 4 can freely rotate in the recess formed in the stator 2. It is housed for that. Moreover, the drive control part T for controlling the drive of this piezoelectric element means 3 is connected to the piezoelectric element means 3, and the stator is driven by driving the piezoelectric element means 3 using the drive control part T. FIG. It is comprised so that the rotor 4 may be rotated about several shafts by vibrating (2).

This object handling apparatus also has a joint mechanism driven by the rotation of the rotor 4 with the rotor 4 of the vibration actuator A as the first joint. The joint mechanism has an output shaft member 5 whose base end is fixed to the rotor 4 and extends linearly from the surface of the rotor 4 toward the radially outer side of the rotor 4, and the output shaft member 5 The first bevel gear 6 is fixed to the tip of the head. On the outer circumferential portion of the output shaft member 5, two annular plates 7 are arranged so as to be free to rotate with respect to the output shaft member 5, respectively, while the outer circumferential portions of these plates 7 have a substantially cylindrical shape. The first node B is fixed, and two plates 7, a part of the output shaft member 5, and the first bevel gear 6 are housed inside the first node B.

A substantially cylindrical second node C is inclinedly connected to the distal end of the first node B via an axis S1 of the second joint. To the end of the second node (C), a substantially cylindrical third node (D) is inclinedly connected through the axis (S2) of the third joint, and the tip of the third node (D) is hemisphere. It is formed in a shape.

The second bevel gear 8 fixed to the proximal end of the second node C is engaged with the first bevel gear 6 positioned at the tip of the output shaft member 5 on the shaft S1 of the second joint. Moreover, the 3rd bevel gear 9 arrange | positioned so as to oppose this 2nd bevel gear 8 is meshed with the 1st bevel gear 6, These 2nd bevel gear 8 and 3rd bevel gear 9 Are independently rotatably arranged around the axis S1 of the second joint. In addition, the fourth bevel gear 10 meshes with the third bevel gear 9, and the fifth bevel gear 11 is integrally formed with the fourth bevel gear 10. The fifth bevel gear 11 is engaged with the sixth bevel gear 12 fixed to the proximal end of the third node D on the axis S2 of the third joint.

The second to fifth bevel gears 8 to 11 are housed inside the second node C, and the fourth bevel gear 10 is provided by a bearing 13 mounted on the inner surface of the second node C. And the shaft of the fifth bevel gear 11 is rotatably supported. In addition, the sixth bevel gear 12 is housed inside the third node D. FIG.

By the first flexible retaining member 14, the first node B is held so as to be tilted relative to the stator 2 and not to rotate about its axis. In addition, by the second flexible retaining member 15, the second node C is held in such a manner that the second node C is tilted relative to the first node B and does not rotate about its axis. The second bevel gear 8 fixed to C) is engaged with the first bevel gear 6, and the third bevel gear 9 is engaged with the first bevel gear 6 and the fourth bevel gear 10, respectively. The state is maintained. In addition, by the third flexible holding member 16, the third node D is held so as to be tilted relative to the second node C and not rotate about its axis, and the third node ( The sixth bevel gear 12 fixed to D) is held in engagement with the fifth bevel gear 11. By these 1st-3rd holding members 14-16, the 1st node B, the 2nd node C, and the 3rd node D are hold | maintained so that it may not come out from the vibration actuator A. FIG.

And while the axis S1 of the second joint is disposed perpendicular to the output shaft member 5, the axis S2 of the third joint is parallel to the axis S1 of the second joint, and the fourth bevel. It is arrange | positioned perpendicular to the axis of the gear 10 and the 5th bevel gear 11.

Next, as shown in FIG. 2, the vibration actuator A is comprised by the ultrasonic actuator which rotates the rotor 4 by ultrasonic vibration. A connecting bolt through which the cylindrical piezoelectric element means 3 is inserted and supported between the base block 1 and the stator 2, and the base block 1 and the stator 2 are passed through the piezoelectric element means 3 ( By connecting to each other via 17), the vibration actuator A as a whole has an approximately cylindrical shape. Here, for convenience of description, the central axis of the cylindrical outline from the base block 1 to the stator 2 is defined as the Z axis, and the X axis in the direction perpendicular to the Z axis is perpendicular to the Z axis and the X axis. It is assumed that the Y axis extends, respectively.

The piezoelectric element means 3 has the 1st-3rd piezoelectric element parts 31-33 on the flat plate located on the XY plane, and mutually superimposed, respectively, and these 1st-3rd piezoelectric element parts 31-33. Are connected to the drive control unit T, respectively.

In the stator 2, the recessed part 18 is formed in the opposite side to the surface which contact | connects the piezoelectric element means 3, The spherical rotor 4 is accommodated in this recessed part 18. As shown in FIG. The recessed part 18 consists of the small diameter part 19 which has an internal diameter smaller than the diameter of the rotor 4, and the large diameter part 20 which has an internal diameter larger than the diameter of the rotor 4, These small diameter parts 19 ) And an annular step 21 positioned on the XY plane at the boundary between the large diameter portion 20 and the large diameter portion 20. The rotor 4 is supported by being able to rotate freely by contacting the step 21 in the recessed part 18.

Moreover, the 1st holding member 14 has hold | maintained the 1st node B with respect to the stator 2 so that the rotor 4 may be pressure-contacted with respect to the stator 2 by predetermined pressure. That is, the 1st holding member 14 comprises the preload means which pressurizes the rotor 4 with respect to the stator 2. As shown in FIG.

As shown in FIG. 3, the 1st-3rd piezoelectric element parts 31-33 are arrange | positioned in the state insulated from each other from the stator 2 and the base block 1 via the insulating sheets 34-37. It is. As for the 1st piezoelectric element part 31 of the piezoelectric element means 3, the electrode plate 38, the piezoelectric element plate 39, the electrode plate 40, the piezoelectric element plate 41, and the electrode plate 42 are sequentially It has a nested structure. Similarly, the second piezoelectric element portion 32 has a structure in which the electrode plate 43, the piezoelectric element plate 44, the electrode plate 45, the piezoelectric element plate 46, and the electrode plate 47 are sequentially stacked. The third piezoelectric element portion 33 has a structure in which the electrode plate 48, the piezoelectric element plate 49, the electrode plate 50, the piezoelectric element plate 51, and the electrode plate 52 are sequentially stacked.

As shown in FIG. 4, in the pair of piezoelectric element plates 39 and 41 of the first piezoelectric element portion 31, portions divided in two in the Y-axis direction have opposite polarities to each other in the Z-axis direction (thickness direction). ), And the piezoelectric element plate 39 and the piezoelectric element plate 41 are arranged upside down.

The pair of piezoelectric element plates 44 and 46 of the second piezoelectric element portion 32 are polarized so as not to be divided into two, but the whole performs deformation behavior of expansion or contraction in the Z axis direction (thickness direction), and the piezoelectric element The plate 44 and the piezoelectric element plate 46 are arranged upside down with each other.

In the pair of piezoelectric element plates 49 and 51 of the third piezoelectric element portion 33, the portions divided in two in the X-axis direction have opposite polarities to each other and are opposite to expansion and contraction in the Z-axis direction (thickness direction), respectively. The piezoelectric element plate 49 and the piezoelectric element plate 51 are arranged inverted to each other so as to perform the deforming behavior to be obtained.

The six piezoelectric element plates 39, 41, 44, 46, 49, and 51 of these first to third piezoelectric element portions 31 to 33 are respectively energized from the drive control section T to generate vibrations, thereby stator 2 ) Is configured to vibrate.

As shown in FIG. 5, the electrode plate 38 positioned at one end portion in the stacking direction of the first piezoelectric element portion 31 corresponds to the two divided portions P1a and P2a of the piezoelectric element plate 39, respectively. And divided into two parts E1a and E2a along the Y-axis direction. Similarly, the electrode plate 42 disposed on the other end of the first piezoelectric element portion 31 in the stacking direction also corresponds to the two divided portions P1b and P2b of the piezoelectric element plate 41, respectively, in the Y axis direction. Thus divided into two parts E1b and E2b. Terminals are drawn out from the two parts E1a and E2a of these electrode plates 38 and the two parts E1b and E2b of the electrode plates 42, respectively, and are connected to the drive control unit T. The electrode plates 40 located in the middle portion of the stacking direction of the first piezoelectric element portion 31 are electrically grounded without being divided into two.

Here, when the energization from the drive control part T to the piezoelectric element means 3 is stopped, when the stress f in the Y direction acts on the piezoelectric element means 3 and the temperature rises by t, The voltage generated in the two portions P1a and P2a of the piezoelectric element plate 39 due to the stress f is the voltage generated in the two portions P1b and P2b of the piezoelectric element plate 41, respectively. Is Vfb, and the voltages generated at the two portions P1a and P2a of the piezoelectric element plate 39 due to the temperature rise t are respectively Vta and the two portions P1b and P2b of the piezoelectric element plate 41. ), When the voltage generated at each Vb is set to Vtb, the two divided portions P1a of the piezoelectric element plate 39 respectively measured by the driving control section T through the two portions E1a and E2a of the electrode plate 38. And the voltages V1a and V2a of P2a),

V1a = Vfa + Vta... (One)

V2a = Vfa-Vta... (2)

And the voltages of the two divided portions P1b and P2b of the piezoelectric element plates 41 respectively measured by the driving control section T via the two portions E1b and E2b of the electrode plate 42. V1b and V2b),

V1b = Vfb + Vtb... (3)

V2b = Vfb-Vtb... (4)

Becomes In addition, since the polarization polarities of the two portions P1a and P2a of the piezoelectric element plate 39 are opposite, in the formulas (1) and (2), the sign of the voltage Vta resulting from the temperature rise t is reversed. . Similarly, since the polarization polarities of the two portions P1b and P2b of the piezoelectric element plate 41 are also opposite, in the formulas (3) and (4), the sign of the voltage Vtb resulting from the temperature rise t is reversed. .

From the formulas (1) and (2),

Vfa = (1/2) ... (V1a + V2a)... (5)

Vta = (1/2) ... (V1a-V2a)... (6)

And in the formulas (3) and (4),

Vfb = (1/2) ... (V1b + V2b)... (7)

Vtb = (1/2)-(V1b-V2b)... (8)

Becomes Therefore, the piezoelectric element plate 39 and the piezoelectric element plate 41 are averaged, and the voltage Vt resulting from the stress f and the voltage Vt resulting from the temperature rise t are

Vf = (1/2) · (Vfa + Vfb)

   = (1/4) · (V1a + V2a + V1b + V2b)... (9)

Vt = (1/2) · (Vta + Vtb)

   = (1/4) (V1a + V1b-V2a-V2b)... 10

Becomes That is, the stress f is proportional to (V1a + V2a + V1b + V2b), and the temperature rise t is proportional to (V1a + V2a-V1b-V2b). Accordingly, at the time of stopping the energization of the piezoelectric element means 3, the drive control unit T includes the voltages V1a and V2a and the piezoelectric elements generated in the two divided portions P1a and P2a of the piezoelectric element plate 39. By measuring the voltages V1b and V2b generated in the two divided portions P1b and P2b of the plate 41, respectively, the stress f and the temperature rise t generated in the Y direction with respect to the piezoelectric element means 3. ) Can be detected.

Although not shown, also in the third piezoelectric element portion 33, similarly to the first piezoelectric element portion 31, the electrode plates 48 and 52 positioned at both ends in the stacking direction thereof are each a piezoelectric element plate 49. And two portions along the X-axis direction corresponding to the two divided portions of 51), and terminals are drawn out from the two divided portions of the respective electrode plates 48 and 52, respectively, and connected to the drive control section T. FIG. It is. Moreover, the electrode plate 50 located in the intermediate part of the lamination direction of the 3rd piezoelectric element part 33 is not divided into two, and is electrically grounded.

In the third piezoelectric element portion 33, the voltage generated in the two divided portions of the piezoelectric element plate 49 and the two divisions of the piezoelectric element plate 51 at the time of stopping the energization of the piezoelectric element means 3. By measuring the voltage which generate | occur | produces in the part with which it was carried out by the drive control part T, the stress f and temperature rise t which generate | occur | produce in the X direction with respect to the piezoelectric element means 3 can be detected.

In addition, as shown in FIG. 6, the three electrode plates 43, 45, 47 of the 2nd piezoelectric element part 32 are not divided into two, and both ends of the 2nd piezoelectric element part 32 in the lamination direction. Terminals are pulled out from the electrode plates 43 and 47 positioned at, respectively, and are connected to the drive control unit T. FIG. The electrode plate 45 located in the middle portion of the stacking direction of the second piezoelectric element portion 32 is electrically grounded.

Here, when the energization from the drive control part T to the piezoelectric element means 3 is stopped, when the stress f in the Z direction is generated in the piezoelectric element means 3 and the temperature rises by t, The voltages generated in the piezoelectric element plates 44 and 46 respectively due to the stress f are Vf1 and Vf2, and the voltages generated in the piezoelectric element plates 44 and 46 respectively due to the temperature rise t are denoted by Vt1. And Vt2, the voltages V1 and V2 of the piezoelectric element plates 44 and 46 measured by the drive control unit T via the electrode plates 43 and 47, respectively,

V1 = Vf1 + Vt1... (11)

V2 = Vf2 + Vt2... (12)

Becomes Here, when said Vt1 and Vt2 are approximated with the voltage Vt resulting from the temperature rise (t) calculated | required in the Y direction or the X direction, Formula (11) and (12) mentioned above are

V1 = Vf1 + Vt

V2 = Vf2 + Vt

Becomes the average of the pair of piezoelectric element plates 44 and 46, and the voltage Vf resulting from the stress f is

Vf = (1/2) · (Vf1 + Vf2)

   = (1/2) · (V1 + V2-2Vt)

Becomes That is, the stress f is proportional to (V1 + V2-2Vt). Therefore, when the energization stops with respect to the piezoelectric element means 3, the drive control part T measures the voltages V1 and V2 which generate | occur | produce in the pair of piezoelectric element boards 44 and 46, and the piezoelectric element means 3 The stress f generated in the Z direction can be detected.

In addition, when the pair of piezoelectric element plates 44 and 46 of the second piezoelectric element portion 32 are formed of a material having a different thermal expansion coefficient, the voltages V1 and V2 generated in these piezoelectric element plates 44 and 46 are different. By measuring, not only the stress but also the temperature can be detected.

Next, operation | movement of the object handling apparatus which concerns on embodiment of this invention is demonstrated. A pair of piezoelectric elements are applied from the drive control unit T to the electrode plates 38 and 42 of the first piezoelectric element unit 31 of the vibration actuator A, respectively, with a frequency close to the natural frequency of the stator 2. When the element plates 39 and 41 are energized, the two divided portions of the pair of piezoelectric element plates 39 and 41 alternately repeat expansion and contraction in the Z axis direction, and the stator 2 in the Y axis direction. Flexural oscillation occurs.

Further, a pair of AC voltages having a frequency close to the natural frequency of the stator 2 is applied to the electrode plates 43 and 47 of the second piezoelectric element portion 32 of the vibration actuator A from the drive control unit T, respectively. When the piezoelectric element plates 44 and 46 are supplied with electricity, the pair of piezoelectric element plates 44 and 46 repeats expansion and contraction in the Z axis direction, so that the stator 2 has a longitudinal direction in the Z axis direction. Generate vibration.

Then, a pair of AC voltages having a frequency close to the natural frequency of the stator 2 is applied to the electrode plates 48 and 52 of the third piezoelectric element portion 33 of the vibration actuator A from the drive control unit T, respectively. When the piezoelectric element plates 49 and 51 are energized, two divided portions of the pair of piezoelectric element plates 49 and 51 alternately repeat expansion and contraction in the Z-axis direction, so that the stator 2 has an X value. Generates bending vibration in the axial direction.

Moreover, when applying an alternating voltage to the electrode plates 38 and 42 of the 1st piezoelectric element part 31 from the drive control part T, the two values of each electrode plate 38 and 42 have the same value. The voltage is set to be applied at the same time. Similarly, even when an alternating current voltage is applied to the electrode plates 48 and 52 of the third piezoelectric element portion 33 from the drive control section T, the two divided portions of each electrode plate 48 and 52 have the same value. The voltage is set to be applied at the same time.

As described above, the bending control in the Y-axis direction by the first piezoelectric element part 31 and the second piezoelectric element part are conducted by energizing the piezoelectric element means 3 of the vibration actuator A by the drive control unit T. As shown in FIG. (32) generates a combined vibration in which two or all of the longitudinal vibration in the Z-axis direction and the bending vibration in the X-axis direction by the third piezoelectric element portion 33 are combined to generate the step of the stator 2. By providing the elliptic vibration to the 21, the rotor 4 can be freely driven to rotate in the three-dimensional direction.

Here, when the rotor 4 of the vibrating actuator A is rotated so that the output shaft member 5 is inclined with respect to the stator 2, the first node B, the first node B, and the first movement are accompanied by the tilt movement of the output shaft member 5. The second section C and the third section D are tilted relative to the stator 2 while maintaining the relative posture of each other.

In addition, when the rotor 4 of the vibration actuator A is rotated to rotate the output shaft member 5 around its own axis, the first bevel gear 6 rotates together with the output shaft member 5. Accompanied by the rotation of the first bevel gear 6, the second bevel gear 8 is rotated about the axis S1 of the second joint, so that the second node C tilts relative to the first node B. And the sixth bevel gear 12 rotates in the same direction as the second bevel gear 8 around the axis S2 of the third joint through the third to fifth bevel gears 9 to 11. The node D moves inclined with respect to the second node C.

Moreover, when the rotor 4 is rotated and the tilting motion of the output shaft member 5 with respect to the stator 2 and the rotation around the axis of the output shaft member 5 are simultaneously performed, the first node B is connected to the stator 2. The second node C is tilted relative to the first node B, and the third node D is tilted relative to the second node C while being tilted relative to the first node B. As shown in FIG.

In this manner, the first control unit B, the second node C, and the first unit B of the joint mechanism are operated by energizing the piezoelectric element means 3 of the vibration actuator A by the drive control unit T to rotate the rotor 4. Each of the three nodes (D) can be tilted to move, so that the joint mechanism can be used to move or grip the object. That is, the object can be handled by the joint mechanism.

Here, for example, when the object M as shown in FIG. 7 is gripped by the joint mechanism and the state is to be maintained, the drive control unit T is connected to the piezoelectric element means 3 of the vibration actuator A. FIG. Stop energization. Even if the energization is stopped in this way, since the rotor 4 of the vibration actuator A is in pressure contact with the stator 2 at a predetermined pressure by the first holding member 14 as the preloading means, the rotor 4 The rotation of the rotor 4 with respect to the stator 2 is prevented by the stop torque between the stators 2. As a result, the relative postures of the stator 2, the first node B, the second node C, and the third node D of the joint mechanism are maintained intact, whereby the object ( M) can be held. In this way, by stopping the energization of the piezoelectric element means 3 from the drive control part T, the handling state of the object M by a joint mechanism is maintained.

Therefore, in order to maintain the state which hold | maintained the object M with a joint mechanism, it is not necessary to continue to energize the vibration actuator A, and, thereby, energy consumption can be reduced. In addition, since the state at that time of the joint mechanism is maintained by stopping the energization of the piezoelectric element means 3 from the drive controller T, the drive controller is controlled by a power failure or the like when the object M is held by the joint mechanism. Even when the energization of the piezoelectric element means 3 suddenly stops from (T), the object M can be held continuously, and the object M can be prevented from falling from the joint mechanism.

In addition, even when the energization of the piezoelectric element means 3 is stopped from the drive control unit T as described above, the drive control unit T remains in the ON state, and the drive control unit T is the piezoelectric element means 3. X, Y to the piezoelectric element means 3 by measuring the voltages of the six piezoelectric element plates 39, 41, 44, 46, 49 and 51 of the first to third piezoelectric element portions 31 to 33 of , Z stress and temperature are detected.

For example, an external force acts on the articulation mechanism or the object M held by the articulation mechanism, and stress is generated in the piezoelectric element means 3 from the articulation mechanism via the rotor 4 and the stator 2. Then, a stress is detected by measuring the voltage which generate | occur | produces in a piezoelectric element plate in that case by the drive control part T. Here, if the detected stress is more than the predetermined value, the drive control part T will energize the piezoelectric element plate of the piezoelectric element means 3 corresponding to the direction of this stress, and will give a rotor torque to the rotor 4 at this time, Maintains the handling state of the object M by the articulation mechanism. Therefore, even when an external force is applied to the joint mechanism or the object M when the object M is gripped by the joint mechanism, the grip can be continued without dropping the object M. FIG.

In this way, the detection of stress and the handling control for the stress can be automatically performed by the object handling apparatus itself.

In addition, since the drive control part T is kept on even when the electricity supply stops with respect to the piezoelectric element means 3, and the vibration actuator A is excellent in responsiveness at the time of electricity supply, the drive control part T is small. When the stationary abnormality stress is detected, the piezoelectric element means 3 is energized and the vibration actuator A is immediately driven to maintain the state in which the object is held by the joint mechanism.

Since the piezoelectric element plates 39, 41, 44, 46, 49, 51 of the piezoelectric element means 3 can be used as stress sensors and temperature sensors to detect stress and temperature, a stress sensor and a temperature sensor are newly formed. There is no need to do this, and therefore, the structure of the object handling apparatus can be simplified and downsized, and the manufacturing cost can be reduced.

Such an object handling apparatus can be applied not only to the finger of the robot hand but also to various parts having a plurality of joints such as the legs of the robot.

In addition, the drive control part T may alternately perform the energization and the energization stop with respect to the piezoelectric element means 3, and may alternately perform the detection of a stress and a temperature, and the drive of a vibration actuator A. FIG.

In addition, by configuring the bridge circuit, the detection of stress and temperature and the drive of the vibration actuator A can be simultaneously performed, whereby the handling of the object by the joint mechanism can be performed with high accuracy. The stress detected in this case is the combined force of the force generated by the driving and the stress applied in the actual handling.

In addition, in the above-mentioned embodiment, as shown in FIG. 8, the vibration actuator A has the same structure as the piezoelectric element means 3, and is mainly used as a sensor, apart from the piezoelectric element means 3. It has a 2nd piezoelectric element means 61, this 2nd piezoelectric element means 61 is laminated | stacked and arrange | positioned with the piezoelectric element means 3, and this 2nd piezoelectric element also when energizing with the piezoelectric element means 3 is carried out. The means 61 can also be configured to not be energized. With this arrangement, even when the vibration actuator A is driven by energizing the piezoelectric element means 3, the drive control section T measures the voltage and the stress of the piezoelectric element plate of the second piezoelectric element means 61 by stress and temperature. Can be detected.

Moreover, when handling an object, when the driving force by the piezoelectric element means 3 is insufficient, the drive control part T energizes also the 2nd piezoelectric element means 61, and the piezoelectric element means 3 and the 2nd The vibrating actuator A can be driven by the driving force of both the piezoelectric element means 61.

Moreover, although the articulation apparatus in embodiment mentioned above had a some bevel gear connected to each other, it is not limited to this, It has various link mechanisms, a wire connection, etc., and it connects a some joint by rotation of the rotor 4, and the like. A driving joint mechanism can also be used.

In addition, although the joint mechanism which has three joints was used in embodiment mentioned above, the joint mechanism which has two or less joints or four or more joints is driven by the rotation of the rotor 4 of the vibration actuator A. FIG. To handle the object.

In addition, instead of using an articulation mechanism, it is also possible to use various mechanisms which are connected to the rotor 4 and driven by the rotation of the rotor 4 to handle objects.

It is also possible to construct an object handling apparatus for handling the object directly by the rotor 4.

Moreover, in the vibration actuator A of the above-mentioned embodiment, although the contact of the stator 2 and the rotor 4 was the level | step difference 21, it is not limited to this structure. If the elliptic motion can be transmitted, it may be brought into flat contact or curved contact, and may not be annular.

In addition, in the above embodiment, instead of the longitudinal vibration in the Z-axis direction, the bending vibration in the Y-axis direction, or the X-axis direction, a composite vibration is generated by combining a plurality of vibrations not perpendicular to each other to rotate the rotor 4. You can also

In addition, although the elliptical motion was generated in the contact part of the stator 2 and the rotor 4, you may generate a circular motion by controlling the amplitude of each axial direction.

In addition, in the above embodiment, bending vibration in the X-axis direction, bending vibration in the Y-axis direction, and longitudinal vibration in the Z-axis direction are generated in separate piezoelectric element portions, and the vibrations are synthesized to generate a composite vibration. One piezoelectric element portion may be polarized in plural and the voltage applied to each polarization electrode may be individually controlled. That is, a composite vibration may be generated in a single piezoelectric element portion by applying a voltage obtained by synthesizing an alternating voltage having different phases, amplitudes, or the like to each polarizing electrode.

The piezoelectric element means 3 may rotate only the rotor 4 by vibrating the stator 2 at the time of energization, and may have only one piezoelectric element plate which can be used as a sensor of stress and temperature at the time of non-energization.

In addition, not only the plate-shaped piezoelectric element but also various piezoelectric elements can be used.

In the above-described embodiment, the rotor 4 is concrete, and a multiple degree of freedom vibration actuator is used in which the stator 2 is vibrated by the piezoelectric element means 3 to rotate the rotor 4 around a plurality of axes. However, one degree of freedom vibration actuator can also be used instead of rotating the rotor around a single axis.

In addition, instead of the spherical rotor 4, an annular rotor can also be used.

Claims (8)

A vibrating actuator having a stator, a rotor in pressure contact with the stator by preloading means, piezoelectric element means connected to the stator, A driving control part for energizing the piezoelectric element means and rotating the rotor to vibrate the stator to handle an object; When the energization of the piezoelectric element means is stopped, the rotation of the rotor is prevented by the pressurization by the preloading means to maintain the handling state of the rotor with respect to the object, The drive control section detects the stress applied to the piezoelectric element means by measuring the voltage of the piezoelectric element means when the energization of the piezoelectric element means is stopped, and when detecting a stress equal to or greater than a predetermined value, the piezoelectric element means. And apply rotational torque to the rotor to maintain the handling state of the rotor with respect to the object. The object handling apparatus according to claim 1, wherein the drive control unit also detects a temperature by measuring a voltage of the piezoelectric element means. The object handling apparatus according to claim 2, wherein the drive control unit also detects a temperature by measuring a voltage of the piezoelectric element means at the time of stopping the energization of the piezoelectric element means. The object handling apparatus according to claim 1, wherein the drive control unit continuously performs alternating energization and energization stop for the piezoelectric element means. The object handling device of claim 1, further comprising a joint mechanism connected to the rotor and driven by the rotation of the rotor, wherein the joint mechanism handles the object by energizing the piezoelectric element means to rotate the rotor. Device. The apparatus of claim 5, wherein the articulation mechanism has a plurality of joints, and the plurality of joints are driven by the rotation of the rotor. 2. The piezoelectric element means according to claim 1, wherein the piezoelectric element means has a plurality of piezoelectric element plates stacked on each other, and the drive control part ellipses the contact portion between the stator and the rotor by energizing the piezoelectric element means to vibrate the stator. And generating one of the circular motions to rotate the rotor around a plurality of axes, and measure the voltage of at least one piezoelectric element plate of the piezoelectric element means when the energization stops with respect to the piezoelectric element means. An object handling apparatus for detecting stress applied to the piezoelectric element means. 2. The vibration actuator according to claim 1, wherein said vibration actuator has a second piezoelectric element means laminated with said piezoelectric element means, and said drive control section measures the voltage of said second piezoelectric element means by energizing said piezoelectric element means. When the driving force is insufficient when detecting the stress applied to the piezoelectric element means and handling the object by rotating the rotor, the second piezoelectric element means is energized to supply the piezoelectric element means and the second piezoelectric element. An object handling apparatus for vibrating the stator by both means.

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