JP6617450B2 - Piezoelectric drive, motor and robot - Google Patents

Description

  The present invention relates to a piezoelectric drive device, a motor, and a robot.

  Conventionally, a piezoelectric actuator (piezoelectric drive device) using a piezoelectric element and a motor using the same are known. For example, Patent Document 1 uses the longitudinal vibration of the longitudinal longitudinal vibration of the elastic plate with one end fixed and the other end free, and the resonance vibration of the higher order mode of bending vibration in the longitudinal direction. An ultrasonic motor that rotates a roller disposed in contact with the elastic plate is disclosed.

Japanese Patent Laid-Open No. 3-11983

  In the ultrasonic motor of Patent Document 1, if the rigidity or mass of the fixing portion (supporting jig) is insufficient, vibration energy leaks to the fixing portion side, and the displacement amount of the vibrator decreases. Therefore, in order to obtain a large output, a large and hard fixing portion is necessary so that leakage of vibration energy to the fixing portion side can be suppressed.

  The present invention has been made in view of the above technical problems. According to some aspects of the present invention, it is possible to provide a piezoelectric drive device, a motor, and a robot that can obtain a large output.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following aspects or application examples.

[Application Example 1]
The piezoelectric drive device according to this application example is
A piezoelectric drive device in which one or more sets of two piezoelectric vibrators having the same shape are fixed to one fixed plate,
The piezoelectric vibrator is
A diaphragm comprising: a fixed portion fixed to the fixed plate; a vibrating body portion provided with a piezoelectric element; and a connecting portion connecting the fixed portion and the vibrating body portion;
A contact portion attached to or in contact with the diaphragm and in contact with the driven body;
Have
Two directions parallel to and orthogonal to the main surface of the diaphragm are defined as an X direction and a Y direction, and a direction perpendicular to the main surface of the diaphragm is defined as a Z direction.
The fixed portion, the vibrating body portion, and the contact portion are provided along the X direction,
The two identically shaped piezoelectric vibrators are piezoelectric driving devices that are driven in opposite phases to each other.

According to this application example, the two piezoelectric vibrators having the same shape are driven in opposite phases to each other, so that the directions of stress applied to the fixed plate act in opposite directions to cancel each other. Accordingly, since leakage of vibration energy to the fixed plate can be reduced, a piezoelectric driving device that can obtain a large output can be realized. Further, the fixed plate can be made small.

[Application Example 2]
In the above piezoelectric drive device,
The two identically shaped piezoelectric vibrators may be arranged side by side in the Y direction.

  According to this application example, since the two piezoelectric vibrators are arranged on the same surface of the fixed plate, a piezoelectric drive device that can be easily manufactured can be realized. In addition, a piezoelectric driving device particularly suitable for a linear motor can be realized.

[Application Example 3]
In the above piezoelectric drive device,
The fixed portions of the two piezoelectric vibrators having the same shape may be integrally formed.

  According to this application example, since the two piezoelectric vibrators can be manufactured by the same manufacturing process, the variation in characteristics of the two piezoelectric vibrators can be reduced. Therefore, since leakage of vibration energy to the fixed plate can be further reduced, a piezoelectric drive device that can obtain a large output can be realized.

[Application Example 4]
In the above piezoelectric drive device,
The piezoelectric vibrator is provided on the main surface of the vibrator part,
In the two identically shaped piezoelectric vibrators, the surfaces where the piezoelectric elements are not formed on the surface on the + Z direction side and the surface on the −Z direction side of the fixed plate, or piezoelectric elements are formed. You may arrange | position so that surfaces may face each other.

  According to this application example, when a rotor having a rotation axis in the Y direction is used as the driven body, the contact portion can be brought into contact without depending on the radius of the rotor. It is also possible to use a plurality of piezoelectric drive devices side by side in the Y direction. Therefore, it is possible to realize a piezoelectric driving device that can obtain a large output.

[Application Example 5]
The motor according to this application example is
The piezoelectric drive device described above;
The driven body;
It is a motor equipped with.

  According to this application example, since the piezoelectric driving device capable of obtaining a large output is used, a motor capable of obtaining a large output can be realized.

[Application Example 6]
The robot according to this application example is
A plurality of link parts;
A joint part connecting the plurality of link parts;
One of the above-described piezoelectric driving devices that drives the joint as the driven body;
It is a robot equipped with.

  According to this application example, since the piezoelectric driving device capable of obtaining a large output is used, a robot capable of obtaining a large output can be realized.

1 is a perspective view schematically showing a piezoelectric driving device according to a first embodiment. It is a top view which shows a diaphragm typically. It is sectional drawing in the AA of FIG. It is a circuit diagram of the drive circuit which drives a piezoelectric vibrator. It is a perspective view which shows typically the mode of operation | movement of the piezoelectric drive device of 1st Embodiment. It is a perspective view which shows typically the piezoelectric drive device which concerns on 2nd Embodiment. It is a perspective view which shows typically the mode of operation | movement of the piezoelectric drive device of 2nd Embodiment. It is a top view which shows typically the motor which concerns on this embodiment. It is explanatory drawing which shows an example of the robot using a piezoelectric drive device. It is explanatory drawing of the wrist part of a robot. It is explanatory drawing which shows an example of the liquid feeding pump using a piezoelectric drive device.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The drawings used are for convenience of explanation. The embodiments described below do not unduly limit the contents of the present invention described in the claims. Also, not all of the configurations described below are essential constituent requirements of the present invention.

1. Piezoelectric drive device 1-1. First Embodiment FIG. 1 is a perspective view schematically showing a piezoelectric driving device 1 according to a first embodiment.

  The piezoelectric drive device 1 according to this embodiment is a piezoelectric drive device 1 in which one or more sets of two piezoelectric vibrators 11 and 12 having the same shape are fixed to one fixed plate 20. The example shown in FIG. 1 is a case where the set of two piezoelectric vibrators 11 and 12 having the same shape is one set, but may be two or more sets. The fixing plate 20 is preferably formed of a material having high rigidity such as stainless steel.

  The piezoelectric vibrator 11 includes a fixed portion 111 fixed to the fixed plate 20, a vibrating body portion 112 provided with a piezoelectric element, and a connecting portion 113 that connects the fixed portion 111 and the vibrating body portion 112. And a contact portion 114 attached to or in contact with the vibration plate 110 and in contact with the driven body.

  The piezoelectric vibrator 12 includes a fixing portion 121 fixed to the fixing plate 20, a vibrating body portion 122 provided with a piezoelectric element, and a connection portion 123 that connects the fixing portion 121 and the vibrating body portion 122. And a contact portion 124 attached to or in contact with the vibration plate 120 and in contact with the driven body.

The contact part 114 and the contact part 124 are members for contacting the driven body and applying force to the driven body. The contact portion 114 and the contact portion 124 are preferably formed of a durable material such as ceramics (for example, alumina Al ₂ O ₃ , zirconia ZrO ₂ , silicon nitride Si ₃ N).

  In the example shown in FIG. 1, two directions parallel to and orthogonal to the main surfaces of diaphragm 110 and diaphragm 120 are defined as an X direction and a Y direction, and directions perpendicular to the main surfaces of diaphragm 110 and diaphragm 120 are defined. The Z direction is assumed.

In the example shown in FIG. 1, when the diaphragm 110 and the contact portion 114 are viewed from the Y direction, the fixed portion 111, the connection portion 113, the vibration body portion 112, and the contact portion 114 are provided in this order along the X direction. It has been. As a result, a large force can be applied to the driven body.

  In the example shown in FIG. 1, when the diaphragm 120 and the contact portion 124 are viewed from the Y direction, the fixing portion 121, the connection portion 123, the vibration body portion 122, and the contact portion 124 are provided in this order along the X direction. It has been. As a result, a large force can be applied to the driven body.

  FIG. 2 is a plan view schematically showing the diaphragm 110 and the diaphragm 120. 3 is a cross-sectional view taken along line AA in FIG.

  The diaphragm 110 and the diaphragm 120 are formed on the substrate 1001, the first electrode 1002 formed on the substrate 1001, the piezoelectric body 1003 formed on the first electrode 1002, and the piezoelectric body 1003. A second electrode 1004. The first electrode 1002 and the second electrode 1004 sandwich the piezoelectric body 1003.

The substrate 1001 is used as a substrate for forming the first electrode 1002, the piezoelectric body 1003, and the second electrode 1004 by a film formation process. The substrate 1001 also has a function as a vibration plate that performs mechanical vibration. The substrate 1001 can be formed of, for example, Si, Al ₂ O ₃ , ZrO ₂ or the like. As the Si substrate 1001, for example, a Si wafer for manufacturing a semiconductor can be used. In this embodiment, the planar shape of the substrate 1001 is a rectangle. The thickness of the substrate 1001 is preferably in the range of 10 μm to 700 μm, for example. When the thickness of the substrate 1001 is 10 μm or more, the substrate 1001 can be handled relatively easily during the film formation process on the substrate 1001. In addition, when the thickness of the substrate 1001 is set to 700 μm or less, the substrate 1001 can be easily vibrated according to the expansion and contraction of the piezoelectric body 1003 formed of a thin film.

  The first electrode 1002 is formed as one continuous conductor layer formed on the substrate 1001. On the other hand, as shown in FIG. 2, the second electrode 1004 is divided into six conductor layers (electrode S1, electrode I1, electrode Z1, electrode S2, electrode I2, and electrode Z2). In the example of FIG. 1, both the first electrode 1002 and the second electrode 1004 have a rectangular planar shape. The first electrode 1002 and the second electrode 1004 are thin films formed by sputtering, for example. As a material of the first electrode 1002 and the second electrode 1004, for example, any material having high conductivity such as Al (aluminum), Ni (nickel), Au (gold), Pt (platinum), Ir (iridium) or the like is used. Is available. Instead of the first electrode 1002 as one continuous conductor layer, the first electrode 1002 may be divided into six conductor layers having substantially the same planar shape as the second electrode 1004. Note that wiring (or a wiring layer and an insulating layer) for electrical connection between the second electrodes 1004 and wiring for electrical connection between the first electrode 1002 and the second electrode 1004 and the drive circuit ( (The wiring layer and the insulating layer) are not shown in FIGS.

  The piezoelectric body 1003 is formed as five piezoelectric layers having substantially the same planar shape as the second electrode 1004. Alternatively, the piezoelectric body 1003 may be formed as one continuous piezoelectric layer having substantially the same planar shape as the first electrode 1002. The laminated structure of the first electrode 1002, the piezoelectric body 1003, and the second electrode 1004 constitutes the piezoelectric vibrator 11 and the piezoelectric vibrator 12 each composed of three piezoelectric elements.

The piezoelectric body 1003 is a thin film formed by, for example, a sol-gel method or a sputtering method. As a material of the piezoelectric body 1003, for example, any material exhibiting a piezoelectric effect, such as ceramics having an ABO ₃ type perovskite structure, can be used. Examples of ceramics having an ABO ₃ type perovskite structure include lead zirconate titanate (PZT), barium titanate, lead titanate, potassium niobate, lithium niobate, lithium tantalate, sodium tungstate, zinc oxide, titanium Barium strontium oxide (BST), strontium bismuth tantalate (SBT), lead metaniobate, lead zinc niobate, lead scandium niobate, or the like can be used. It is also possible to use a material exhibiting a piezoelectric effect other than ceramic, such as polyvinylidene fluoride and quartz. The thickness of the piezoelectric body 1003 is preferably in the range of, for example, 50 nm (0.05 μm) to 20 μm. A thin film of the piezoelectric body 1003 having a thickness in this range can be easily formed using a film formation process. If the thickness of the piezoelectric body 1003 is 0.05 μm or more, a sufficiently large force can be generated according to the expansion and contraction of the piezoelectric body 1003. Moreover, if the thickness of the piezoelectric body 1003 is 20 μm or less, the piezoelectric driving device 1 can be sufficiently downsized.

  In the present embodiment, two identically shaped piezoelectric vibrators 11 and 12 are driven in opposite phases.

  FIG. 4 is a circuit diagram of a drive circuit that drives the piezoelectric vibrator 11 and the piezoelectric vibrator 12.

  In FIG. 4, the power supply VS0 and the power supply VS180 output alternating voltages whose phases are shifted by 180 degrees.

  An AC voltage from the power source VS0 is input to the electrode S1 and the electrode I1 of the piezoelectric vibrator 11 via the resistor R1. An AC voltage from the power source VS180 is input to the electrode Z1 of the piezoelectric vibrator 11 via the resistor R2.

  An AC voltage from the power source VS180 is input to the electrode S2 and the electrode I2 of the piezoelectric vibrator 12 via the resistor R2. An AC voltage from the power source VS0 is input to the electrode Z2 of the piezoelectric vibrator 12 via the resistor R1.

  A ground potential is commonly input to the first electrodes 1002 of the piezoelectric vibrator 11 and the piezoelectric vibrator 12.

  In the example shown in FIG. 4, when the piezoelectric body 1003 in the vicinity of the electrode S1 and the electrode I1 of the piezoelectric vibrator 11 expands, the piezoelectric body 1003 in the vicinity of the electrode Z1 of the piezoelectric vibrator 11 contracts. When the piezoelectric body 1003 in the vicinity of the electrode S1 and the electrode I1 of the piezoelectric vibrator 11 contracts, the piezoelectric body 1003 in the vicinity of the electrode Z1 of the piezoelectric vibrator 11 expands.

  In the example shown in FIG. 4, when the piezoelectric body 1003 in the vicinity of the electrode S2 and the electrode I2 of the piezoelectric vibrator 12 expands, the piezoelectric body 1003 in the vicinity of the electrode Z2 of the piezoelectric vibrator 12 contracts. When the piezoelectric body 1003 in the vicinity of the electrode S2 and the electrode I2 of the piezoelectric vibrator 12 contracts, the piezoelectric body 1003 in the vicinity of the electrode Z2 of the piezoelectric vibrator 12 expands.

  FIG. 5 is a perspective view schematically showing an operation state of the piezoelectric driving device 1 of the first embodiment. In FIG. 5, the magnitude of the bending of the piezoelectric vibrator 11 and the piezoelectric vibrator 12 is exaggerated.

  In the example shown in FIG. 5, the piezoelectric body 1003 in the vicinity of the electrode S1 and the electrode I1 of the piezoelectric vibrator 11 is extended, and the piezoelectric body 1003 in the vicinity of the electrode Z1 of the piezoelectric vibrator 11 is contracted. Further, the piezoelectric body 1003 in the vicinity of the electrode S2 and the electrode I2 of the piezoelectric vibrator 12 is contracted, and the piezoelectric body 1003 in the vicinity of the electrode Z2 of the piezoelectric vibrator 12 is in a stretched state.

As the piezoelectric vibrator 11 expands and contracts, the contact portion 114 draws an elliptical locus in the XY plane. Further, as the piezoelectric vibrator 12 expands and contracts, the contact portion 124 draws an elliptical locus in the XY plane. By this operation, the driven body that contacts the contact portion 114 or the contact portion 124 can be sent out in the Y direction.

  According to the present embodiment, the two piezoelectric vibrators 11 and 12 having the same shape are driven in opposite phases to each other, so that the directions of stress applied to the fixed plate 20 act in opposite directions to cancel each other. Therefore, since leakage of vibration energy to the fixed plate 20 can be reduced, the piezoelectric driving device 1 that can obtain a large output can be realized. Moreover, the volume and mass of the fixed plate 20 can be reduced.

  In the present embodiment, the two piezoelectric vibrators 11 and 12 having the same shape are arranged side by side in the Y direction.

  According to the present embodiment, since the two piezoelectric vibrators 11 and 12 are arranged on the same surface of the fixed plate 20, the piezoelectric drive device 1 that is easy to manufacture can be realized. In addition, the piezoelectric drive device 1 that is particularly suitable for a linear motor can be realized.

  In the present embodiment, the fixed portion 111 of the two piezoelectric vibrators 11 having the same shape and the fixed portion 121 of the piezoelectric vibrator 12 are integrally formed.

  According to this embodiment, since the two piezoelectric vibrators 11 and the piezoelectric vibrators 12 can be manufactured by the same manufacturing process, variation in characteristics of the two piezoelectric vibrators 11 and the piezoelectric vibrators 12 can be reduced. Therefore, since leakage of vibration energy to the fixed plate 20 can be further reduced, the piezoelectric driving device 1 that can obtain a large output can be realized.

1-2. Second Embodiment FIG. 6 is a perspective view schematically showing a piezoelectric driving device 2 according to a second embodiment. The same components as those of the piezoelectric driving device 1 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The piezoelectric driving device 2 according to the second embodiment is different from the piezoelectric driving device 1 in the arrangement of the piezoelectric vibrator 11 and the piezoelectric vibrator 12 with respect to the fixed plate 20, and the other configuration is the same as that of the piezoelectric driving device 1.

  The laminated structure of the piezoelectric vibrator 11 and the piezoelectric vibrator 12 is the same as the structure shown in FIG. The second electrode 1004 of the piezoelectric vibrator 11 is provided in the order of the electrode Z1, the electrode I1, and the electrode S1 in the + Y direction. The second electrode 1004 of the piezoelectric vibrator 12 is provided in the order of the electrode Z2, the electrode I2, and the electrode S2 in the + Y direction. The drive circuit for driving the piezoelectric vibrator 11 and the piezoelectric vibrator 12 has the same configuration as that shown in FIG.

  In the present embodiment, the piezoelectric vibrator provided in the piezoelectric vibrator 11 is provided on one main surface of the vibrating body portion 112 of the diaphragm 110. The piezoelectric vibrator provided in the piezoelectric vibrator 12 is provided on one main surface of the vibrating body portion 122 of the diaphragm 120.

  The two piezoelectric vibrators 11 and 12 having the same shape are formed on the surfaces where the piezoelectric elements are not formed on the surface on the + Z direction side and the surface on the −Z direction side of the fixed plate 20, or the piezoelectric elements. It is arranged so that the faces on which are formed face each other.

  FIG. 7 is a perspective view schematically showing an operation state of the piezoelectric driving device 2 of the second embodiment. In FIG. 7, the magnitude of bending of the piezoelectric vibrator 11 and the piezoelectric vibrator 12 is exaggerated.

  In the example shown in FIG. 7, the piezoelectric body 1003 in the vicinity of the electrode S1 and the electrode I1 of the piezoelectric vibrator 11 is extended, and the piezoelectric body 1003 in the vicinity of the electrode Z1 of the piezoelectric vibrator 11 is contracted. Further, the piezoelectric body 1003 in the vicinity of the electrode S2 and the electrode I2 of the piezoelectric vibrator 12 is contracted, and the piezoelectric body 1003 in the vicinity of the electrode Z2 of the piezoelectric vibrator 12 is in a stretched state.

  As the piezoelectric vibrator 11 expands and contracts, the contact portion 114 draws an elliptical locus in the XY plane. Further, when the piezoelectric vibrator 12 expands and contracts, the contact portion 124 draws an elliptical locus in the XY plane. By this operation, the driven body that contacts the contact portion 114 or the contact portion 124 can be sent out in the Y direction.

  Also in this embodiment, the two piezoelectric vibrators 11 and 12 having the same shape are driven in opposite phases to each other, so that the directions of stress applied to the fixed plate 20 act in opposite directions to cancel each other. Therefore, since leakage of vibration energy to the fixed plate 20 can be reduced, the piezoelectric driving device 1 that can obtain a large output can be realized. Moreover, the volume and mass of the fixed plate 20 can be reduced.

  Further, according to the present embodiment, when a rotor having a rotation axis in the Y direction is used as the driven body, the contact portion 114 or the contact portion 124 can be brought into contact regardless of the radius of the rotor. It is also possible to use a plurality of piezoelectric drive devices 2 side by side in the Y direction. Therefore, the piezoelectric driving device 2 that can obtain a large output can be realized.

1-3. Simulation Example Table 1 shows the simulation results by the finite element method. The material of the fixing plate was stainless steel, and the size of the fixing plate was 5 mm in the X direction, 5 mm in the Y direction, and 1 mm in the Z direction. The material of the piezoelectric vibrator was silicon, and the size of the piezoelectric vibrator was 2.5 mm in the X direction, 1 mm in the Y direction, and 0.2 mm in the Z direction.

  In Table 1, the tip displacement ratio and output indicate relative values when the number of piezoelectric vibrators is one and 100%. The “two identical surfaces” of the piezoelectric vibrator have the configuration shown in FIG. 1, and the “two double surfaces” have the configuration shown in FIG. The “in-phase” phase is when the phase difference between VS0 and VS180 of the drive circuit shown in FIG. 4 is 0 degree, and the “reverse phase” is when the phase difference is 180 degrees.

  As shown in Table 1, when the phase is the same, the output is less than 200% even when two piezoelectric vibrators are used, whereas when the phase is opposite, the output exceeds 200%. ing. Therefore, it was confirmed that a piezoelectric driving device capable of obtaining a large output can be realized by driving the two piezoelectric vibrators in opposite phases.

2. Motor FIG. 8 is a plan view schematically showing a motor 50 according to the present embodiment.

  The motor 50 according to this embodiment includes the above-described piezoelectric driving device 1 and a driven body 500. In the example illustrated in FIG. 8, the motor 50 is a linear motor that linearly moves the driven body 500. The driven body 500 is provided so as to contact at least one of the contact portion 114 and the contact portion 124 during the operation of the piezoelectric driving device 1. The piezoelectric driving device 1 can move the driven body 500 in the Y direction by expansion and contraction of the piezoelectric vibrator 11 and the piezoelectric vibrator 12.

  According to this embodiment, since the piezoelectric drive device 1 that can obtain a large output is used, the motor 50 that can obtain a large output can be realized.

  Even when the piezoelectric driving device 2 is used in place of the piezoelectric driving device 1, the same effect can be obtained. The driven body 500 may be configured as a rotor that rotates.

3. Robot FIG. 9 is an explanatory diagram showing an example of a robot 2050 using the piezoelectric driving device 1 described above. The robot 2050 includes an arm 2010 (“arm”) including a plurality of link portions 2012 (also referred to as “link members”) and a plurality of joint portions 2020 that connect the link portions 2012 in a rotatable or bendable state. Part). Each joint unit 2020 incorporates the piezoelectric drive device 1 described above, and the piezoelectric drive device 1 drives the joint unit 2020 as a driven body. In the present embodiment, the joint portion 2020 can be rotated or bent by an arbitrary angle using the piezoelectric driving device 1. A robot hand 2000 is connected to the tip of the arm 2010. The robot hand 2000 includes a pair of grip portions 2003. The robot hand 2000 also has a built-in piezoelectric driving device 1, and the piezoelectric driving device 1 can be used to open and close the gripping part 2003 to grip an object. The piezoelectric drive device 1 is also provided between the robot hand 2000 and the arm 2010, and the robot hand 2000 can be rotated with respect to the arm 2010 using the piezoelectric drive device 1.

  FIG. 10 is an explanatory diagram of the wrist portion of the robot 2050 shown in FIG. The wrist joint portion 2020 holds the wrist rotation portion 2022, and the wrist link portion 2012 is attached to the wrist rotation portion 2022 so as to be rotatable around the central axis O of the wrist rotation portion 2022. . The wrist rotation unit 2022 includes the piezoelectric driving device 1, and the piezoelectric driving device 1 rotates the wrist link unit 2012 and the robot hand 2000 around the central axis O. The robot hand 2000 is provided with a plurality of gripping units 2003. The proximal end portion of the grip portion 2003 is movable in the robot hand 2000, and the piezoelectric driving device 1 is mounted on the base portion of the grip portion 2003. For this reason, by operating the piezoelectric driving device 1, the object can be gripped by moving the gripping part 2003.

  Note that the robot is not limited to a single-arm robot, and the piezoelectric drive device 1 can be applied to a multi-arm robot having two or more arms. Here, in the wrist joint 2020 and the robot hand 2000, in addition to the piezoelectric driving device 1, a power line for supplying power to various devices such as a force sensor and a gyro sensor, a signal line for transmitting a signal, and the like And requires a lot of wiring. Therefore, it is very difficult to arrange wiring inside the joint portion 2020 and the robot hand 2000. However, since the piezoelectric drive device 1 of the above-described embodiment can obtain a larger output than a normal electric motor or a conventional piezoelectric drive device and can also reduce the size of the device, the joint portion 2020 (particularly, the arm 2010). Wiring can be arranged even in a small space such as the joint at the tip or the robot hand 2000.

  FIG. 11 is an explanatory view showing an example of a liquid feed pump 2200 using the above-described piezoelectric driving device 1. The liquid feed pump 2200 includes a reservoir 2211, a tube 2212, a piezoelectric driving device 1, a rotor 2222, a deceleration transmission mechanism 2223, a cam 2202, a plurality of fingers 2213, 2214, 2215, 2216, and a case 2230. 2217, 2218, and 2219 are provided. The reservoir 2211 is a storage unit for storing a liquid to be transported. The tube 2212 is a tube for transporting the liquid sent out from the reservoir 2211. The piezoelectric driving device 1 is provided in a state of being pressed against the side surface of the rotor 2222, and the piezoelectric driving device 1 rotationally drives the rotor 2222. The rotational force of the rotor 2222 is transmitted to the cam 2202 via the deceleration transmission mechanism 2223. Fingers 2213 to 2219 are members for closing the tube 2212. When the cam 2202 rotates, the fingers 2213 to 2219 are sequentially pushed outward in the radial direction by the protrusion 2202A of the cam 2202. The fingers 2213 to 2219 close the tube 2212 in order from the upstream side in the transport direction (reservoir 2211 side). Thereby, the liquid in the tube 2212 is transported to the downstream side in order. In this way, it is possible to realize a small liquid feed pump 2200 that can feed a very small amount with high accuracy. In addition, arrangement | positioning of each member is not restricted to what was illustrated. Further, a member such as a finger may not be provided, and a ball or the like provided on the rotor 2222 may close the tube 2212. The liquid feed pump 2200 as described above can be used for a medication device that administers a drug solution such as insulin to the human body. Here, by using the piezoelectric driving device 1 of the above-described embodiment, a larger output than the conventional piezoelectric driving device can be obtained and the size of the device can be reduced, so that the dosing device can be miniaturized.

  The present invention is not limited to the present embodiment, and various modifications can be made within the scope of the gist of the present invention.

  The above-described embodiments and modifications are merely examples, and the present invention is not limited to these. For example, it is possible to appropriately combine each embodiment and each modification.

  The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same objects and effects). In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that achieves the same effect as the configuration described in the embodiment or a configuration that can achieve the same object. In addition, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

DESCRIPTION OF SYMBOLS 1, 2 ... Piezoelectric drive device 11, 12 ... Piezoelectric vibrator, 20 ... Fixed plate, 50 ... Motor, 110 ... Vibration plate, 111 ... Fixed part, 112 ... Vibrating body part, 113 ... Connection part, 114 ... Contact part DESCRIPTION OF SYMBOLS 120 ... Diaphragm 121 ... Fixed part 122 ... Vibrating body part 123 ... Connection part 124 ... Contact part 500 ... Driven body 1001 ... Substrate 1002 ... First electrode 1003 ... Piezoelectric body 1004 ... Second electrode, 2000 ... Robot hand, 2003 ... Gripping part, 2010 ... Arm, 2012 ... Link part, 2020 ... Joint part, 2022 ... Wrist rotating part, 2050 ... Robot, 2200 ... Liquid feeding pump, 2202 ... Cam, 2202A ... Projection, 2211 ... Reservoir, 2212 ... Tube, 2213 ... Finger, 2222 ... Rotor, 2223 ... Deceleration transmission mechanism, 2230 ... Case, I1, I , S1, S2, Z1, Z2 ... electrode, R1, R2 ... resistance, VS0, VS180 ... Power

Claims (6)

A piezoelectric drive device comprising a first piezoelectric vibrator and the second piezoelectric vibrator is fixed to a solid Teiita,
The first piezoelectric vibrator and the second piezoelectric vibrator are:
A vibration plate having a fixed portion fixed to the fixed plate, a vibration body portion provided with a piezoelectric element, and a connection portion connecting the fixed portion and the vibration body portion;
A contact portion disposed on the diaphragm and in contact with the driven body;
Equipped with a,
When two directions parallel to and orthogonal to the main surface of the diaphragm are defined as an X direction and a Y direction, and a direction perpendicular to the main surface of the diaphragm is defined as a Z direction,
The first piezoelectric vibrator and the second piezoelectric vibrator are provided with the fixed portion, the vibrating body portion, and the contact portion along the X direction,
The first piezoelectric vibrator is
A first electrode;
A second electrode including a first conductor layer, a second conductor layer, and a third conductor layer;
A first piezoelectric body provided between the first electrode and the second electrode;
Have
The second piezoelectric vibrator is
A third electrode;
A fourth electrode including a fourth conductor layer, a fifth conductor layer, and a sixth conductor layer;
A second piezoelectric body provided between the third electrode and the fourth electrode;
Have
The first conductor layer, the second conductor layer, and the third conductor layer are arranged in the order of the first conductor layer, the second conductor layer, and the third conductor layer along the Y direction. Arranged,
The fourth conductor layer, the fifth conductor layer, and the sixth conductor layer are arranged in the order of the fourth conductor layer, the fifth conductor layer, and the sixth conductor layer along the Y direction. Arranged,
A first AC voltage is input to the second conductor layer, the third conductor layer, and the fourth conductor layer,
A second AC voltage whose phase is shifted by 180 degrees from the first AC voltage is input to the first conductor layer, the fifth conductor layer, and the sixth conductor layer.
A piezoelectric driving device in which a ground potential is input to the first electrode and the third electrode . The piezoelectric drive device according to claim 1 ,
The previous SL said first piezoelectric vibrator second piezoelectric vibrators are arranged side by side in the Y-direction, the piezoelectric drive device. The piezoelectric drive device according to claim 2,
The piezoelectric driving device, wherein the fixed portion of the first piezoelectric vibrator and the fixed portion of the second piezoelectric vibrator are configured as a single unit. The piezoelectric drive device according to claim 1,
The piezoelectric element is provided on a main surface of the vibrating body part ,
The previous SL first piezoelectric vibrator and the second piezoelectric vibrator, wherein a + Z direction side surface and the -Z direction side surface of the fixing plate, each other face not another of said piezoelectric elements are formed, or, A piezoelectric driving device arranged such that surfaces on which the piezoelectric elements are formed face each other. A piezoelectric driving device according to any one of claims 1 to 4,
The driven body;
Equipped with a motor. A plurality of link parts;
A joint part connecting the plurality of link parts;
The piezoelectric drive device according to claim 1, wherein the joint portion is driven as the driven body.
Equipped with a robot.

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