Showing papers on "Bimorph published in 1987"

Bimorph actuator for a disk drive

Abstract: A movable actuator supporting a stacked assembly of read/write heads for unitary movement adjacent respective disk surfaces of a disk drive mechanism, the movable actuator incorporating a series of secondary actuators, one for each head, each secondary actuator including a bimorph member with piezoelectric properties, and capable of extremely precise movements for secondary positioning.

Piezo-electric device

Abstract: A piezo-electric device such as a piezo bimorph device includes an intermediate plate, a plate-shaped first piezo ceramic element fixed on one surfaces of the intermediate plate, a plate-shaped second piezo ceramic element fixed on the other surface of the intermediate plate, and a lead wire for connecting the first piezo ceramic element with the second piezo ceramic element. The intermediate plate is made of a hardened tool steel containing carbon from 0.6 to 1.5%, or a fine ceramic material.

Bimorph‐driven x–y–z translation stage for scanned image microscopy

Abstract: We have developed an x–y–z scanning stage for mechanically scanned microscopy. The stage is constructed of ‘‘double‐S’’ mode piezoelectric bimorphs. The prototype unit has a deflection sensitivity of 0.3 μm/V and a travel in each of the three axes of ±60 μm. The lowest mechanical resonances of the stage are at 190, 220, and 360 Hz, corresponding to the x, y, and z axes of the stage, respectively. The noise level of the stage, when mounted on an isolation table, is ∼0.1 nm. The performance of the stage can be understood in terms of a simple lumped element model which can be used to optimize such stages for particular applications.

Piezoelectric relays in sealed enclosures

Abstract: A piezoceramic relay (20) is disclosed having a bimorph actuating member (22) cantilever mounted within an enclosure (36) of various forms and materials. The enclosures may be moisture-proof and/or hermetically sealed to maintain a vacuum or a protective gaseous atmosphere in which the relay contacts operate. The electrical terminations (46a,48a) of the relay are brought out externally of the enclosure in a form compatible with a plug receptacle (54). To ensure precision contact gaps, removable spacers are positioned between the stationary and movable contacts during prepolarization of the bimorph member.

Magnetic head driving apparatus

Abstract: An apparatus for driving a magnetic head including a monolithic bimorph member. A first end of the monolithic bimorph member has the magnetic head fixed thereto, and the other end thereof is fixed to a support member to be supported by the support member. The monolithic bimorph member comprises a piezoelectric ceramic sintered body formed from a plurality of electrodes stacked alternately with ceramic layers. The plurality of electrodes includes first and second electrode groups which are electrically connected with each other by conductors in through holes. The through holes are provided in portions of the sintered body close to the end fixed to the support member.

Detecting device for abnormality of sheet

Abstract: PURPOSE: To miniaturize a device and lower a cost by providing a piezoelectric element as a pickup for detecting the abnormality of a sheet, and an abnormality detecting circuit which inputs the output voltage from this piezoelectric element as an abnormality detecting signal to generate an abnormality signal. CONSTITUTION: A bimorph type piezoelectric element 4 is fixed by means of the shaft 3 of a displaceable roller 2 and a fixing tool 5 and held in a form of cantilever. When a sheet 7 passes between a fixed roller 1 and the displaceable roller 2, the displaceable roller 2 is displaced downward. This displacement is transmitted to the piezoelectric element 4, which is displaced generating a voltage. This voltage is inputted into a detecting circuit 6 as a signal. Also, when the sheet 7 passes between both rollers 1, 2, a sheet passage signal is detected by an optical sensor 8 and inputted into the detecting circuit 6. The detecting circuit 6 judges whether the sheet 7 is normal or not based on the signal of the piezoelectric element 4 and the passage signal of the sensor 8. By this structure, since a displacement transmitting mechanism is not necessary, the device can be miniaturized lowering a cost. COPYRIGHT: (C)1989,JPO&Japio

Piezoelectric transducer and transformer circuit

Abstract: An electroacoustic piezoelectric transducer, particularly useful as a high frequency loudspeaker or tweeter, includes a concave diaphragm mounted in a housing along its periphery outwardly of a peripheral inflection region thereof. A substantially square piezoelectric bimorph element is affixed to a central region of the inner concave surface of the diaphragm by securing each of its four corners to the diaphragm. The bimorph element is directly coupled to a transformer in an electrical circuit including a low voltage AC source for applying an alternating voltage thereto. In operation when an appropriate alternating voltage is applied to the square bimorph element, in-phase vibrational displacements of the four corners thereof which are fixed to the diaphragm occur which cause the diaphragm to vibrate in its entirety about its peripheral inflection region to produce sound at an amplitude greater than the amplitude of vibration of the bimorph element. The transformer provides an increased excitation level so that the bimorph element provides good high frequency response. By virtue of the direct connection between the transformer and the piezoelectric bimorph element, the sensitivity of the bimorph element increases up to 15 db depending on the turn ratio of the transformer. The bandwidth can also be controlled in a range of between about 3 kHz to 30 kHz through suitable design of the primary inductance of the transformer.

Self-loading actuator mechanism for negative floating head

Abstract: PURPOSE:To ensure satisfactory record/reproduction characteristics by using a pair of support springs of thin plate beam structure which are attached to an attachment arm for magnetic head and a piezoelectric element of bimorph structure. CONSTITUTION:The piezoelectric elements 2 of bimorph structure are used together with a pair of support springs 3 of thin plate beam structure which are attached to a magnetic head attaching arm 1 for a magnetic disk device. These elements 2 and springs 3 are joined together by means of a viscoelastic body 4 at the support spring part. Furthermore, a floating head slider 6 using negative pressure and a tongue-shaped gimbal spring 5 which supports the slider 6 are attached to one of both springs 3. Then the voltage is applied to a pair of elements 2 attached to the arm 1 as soon as a recording medium 7 is rotated. Thus the elements 2 are deformed so that a negative floating head is brought close to the surface of the medium 7. Then the voltage applied to the elements 2 is deleted before the medium 7 stops completely. Thus the floating head can be reset to its first static state.

Magnetic head displacing device

Abstract: PURPOSE:To avoid separation between a magnetic head and a recording medium despite the bend of a bimorph piezoelectric element supporting the magnetic head and at the same time to obtain a thin and compact displacement device for the magnetic head, by setting said piezoelectric element so that the bent plane of the piezoelectric element is set parallel with a magnetic recording medium. CONSTITUTION:A pair of bimorph piezoelectric elements 18f and 18f are set to that the polarizing directions of piezoelectric elements 11f and 12f are set opposite to those of piezoelectric elements 11r and 12r and also that an electrode 13f is connected to an electrode 13r via a connection line 32 together with electrodes 16f and 16r connected via a connection line 33 respectively. In such a constitution, both bent electric terminals 22 and 23 bend in the direction opposite to each other when the drive voltage is applied between both terminals 22 and 23. Furthermore, the length is fixed at the same value among those elements 11f, 12f, 11r and 13r so as to secure the same bend value between both elements 18f and 18r. Then both elements 18f and 18r are set so that their bent displacement planes are parallel with the plane of a magnetic disk (magnetic recording medium) 24.

Piezoelectrically driven valve

Abstract: PURPOSE:To control a flow rate from a very small volume to a relatively large volume, by constructing a valve body for controlling a flow rate of a piezoelectric element using an piezoelectric ceramics. CONSTITUTION:A valve body 8 for opening and closing a valve body is gripped between a housing 9 positioned at an opposite side of a valve main body 1 and the valve main body. The valve body 8 comprises a piezoelectric unimorph or a piezo-electric bimorph and the like composed of a piezoelectric ceramics body 13 fixed to one side of a diaphragm plate 12. When DC voltage is imposed on the piezoelectric ceramics 13, a piezoelectric element is bent to convex or concave at its peripheral to central portions. The bending motion of the piezoelectric element as the valve body 8 permits the valve body to be seated on a valve seat 7 or to be apart therefrom for controlling a flow rate.

Piezo-electric type gas flow control valve

Abstract: PURPOSE:To always accurately control a flow amount in no relation to a difference between the inflow pressure of primary side gas and the outflow pressure of secondary side gas, by using a material, in which a piezo-electric porcelain plate is formed into bimorph construction, for the driving part of a valve. CONSTITUTION:A piezo-electric porcelain bimorph 1, supported by supporting parts 8, is mounted in a valve chamber 4. Voltage is applied to the bimorph 1, and when a primary side gas inflow port 2 is closed, the same pressure to the inside of the valve chamber 4 is applied also to obverse and reverse sides of the bimorph 1 by the Pascal's principle if the point end area of the primary side gas inflow port 2 is formed sufficiently small. No voltage is applied to the bimorph 1, and if the primary side gas inflow port 2 is placed in an opened condition, the uniform pressure is applied to also the bimorph 1. In this way, the bimorph 1 is prevented from generating distortion by external force.

Magnetic recording device

Abstract: PURPOSE:To prevent generation of the crosstalk by displacing other magnetic head from the normal position in applying recording or reproduction of a channel by using one optional head among multi-channel magnetic heads. CONSTITUTION:While a switch 9A is turned on and the channel A is reproduced, an input level of an inverter 27 goes to a low level in an A channel bimorph drive circuit 18A, a voltage impressed to an A channel bimorph plate 12A is zero and the magnetic head 2A is held at a normal position. During this time, the input of an inverter 27 goes to a high level in a B channel bimorph drive circuit 18B, transistors 23, 24 are both turned off and the voltage impressed to the B-channel bimorph plate 12B is expressed as E1B=-E2Bnot equal to 0 and the magnetic head 2B is deviated from the normal position. Conversely, the switch 5B is turned on and the B channel is reproduced, then the magnetic head 2A is deviated from the normal position. Thus, no crosstalk is caused even at time of recording and reproduction.

Vibration isolating device

Abstract: PURPOSE:To eliminate vibration of an upper plate, by a method wherein an actuator, provided with a lamellar resilient member and piezoelectric elements formed on the upper and the under surface of the resilient member, is provided, and the piezoelectric element is displaced in a reverse direction to that of an output signal from a sensor electrode CONSTITUTION:An actuator 7 is formed with a contact member 9 approximately making contact with an under surface 3a of on upper plate 3, a bimorph type piezoelectric element 10 holding the contact member 9, and a casing 11 containing and holding the piezoelectric element The piezoelectric element 10 is horizontally held such that both end parts 12a and 12b of a resilient shim 12 ore engaged internally of a groove 11b of the casing 11 A sensor electrode 15 outputs a signal to a detecting part according to a strain produced when the piezoelectric element 10 is bent in directions X1 and X2 A voltage is applied from a control output part on an actuator electrode 16, which is displaced in a longitudinal direction Thus, By means of an output signal from the sensor electrode 15, vibration can be directly detected through the contact member 9 This constitution enables excellent damping of vibration through further precise control of the actuator electrode 16

Heat dissipation fin with piezoelectric fan

Abstract: PURPOSE:To enhance a forced heat dissipation effect as well as to enable an automatic control of the intensity of a blast by utilizing the temperature characteristics of piezoelectric elements by a method wherein a heat dissipation plate of a heat dissipation fin is provided with a piezoelectric fan and which supplied the blast. CONSTITUTION:Each piezoelectric fan 3 is installed in an apertures 2 formed in each of plural heat dissipation plates 1 facing upward. The piezoelectric fan 3 consists of an elastic plate 4 and a piezoelectric element 5 and one end of the element 5 is fixed on the head dissipation plate 1 directly or interposing an excellent heat transfer elastic material between them. Accordingly, by impressing an AC voltage having a proper frequency on the piezoelectric elements 5, the piezoelectric fans 3 are driven, a blast is supplied to the heat-dissipation plates 1 from their low directions and a heat dissipation effect can be augmented. The heat dissipation plates 1 are provided with the piezoelectric elements 5, the temperature coefficient of the piezoelectric constant d31 of which is positive and which are 1,000ppm/ deg.C or more, using various transverse effect type elements of a unimorph, a bimorph, a laminated unimorph and a laminated bimorph, whereby the blast intensity of the piezoelectric fans 3 can be automatically controlled according to the temperature of the heat dissipation plates 1 without using a special temperature detecting means.

Modulation Type Pyroelectric IR Detector

Abstract: We have developed a new type of pyroelectric IR detector which contains a sensing part and a solid state chopper with two bimorph vibrators and two slit plates in the same package. This new detector (M-type IR detector) features high reliability, small volume and low electric power consumption compared with conventional pyroelectric IR detectors using a rotating chopper. The output voltage and noise voltage of the M-type IR detector have been investigated theoretically and experimentally. It was confirmed that a good performance can be achieved in the M-type IR detector by optimizing the relative position of the two slit plates and the aperture diameter of the shield box.

Travel device in duct line

Abstract: PURPOSE: To simplify a mechanism and miniaturize a device, by providing a travel device with a piezoelectric unit and a shape memory alloy. CONSTITUTION: On the side surface of the piezoelectric bimorph 15 of two piezoelectric elements which are put together, two sets of resistors 14 confronted with each other are arranged. By applying AC voltage to the piezoelectric elements, flexible oscillation is generated on the bimorph 15. By this flexible oscillation, the resistors 14 are oscillated alternately on the left and right in the direction of a duct axis. Then, by applying a shape memory alloy wire 16 to this oscillation, a moving mechanism which can be run in both the left and right directions is considered. In other words, by conducting current to a shape memory alloy A to heat it and by transforming the resistors 14 to remove the tips from a duct line, the mechanism is run in the left direction. By repeating this action, the mechanism is continuously advanced. On the contrary, when current is conducted to a shape memory alloy B, then the mechanism is run in the counter direction by the same action. Accordingly, a wheel or a motor is not used, and so the mechanism is simplified and is easily manufactured and can be miniaturized. COPYRIGHT: (C)1988,JPO&Japio

Blade mechanism of piezoelectric type blower

Abstract: PURPOSE:To reduce the noise and cost of captioned mechanism and miniaturize it by oscillating each of the flaps of a flap section at the approximately same amplitude by charging voltage to a piezoelectric type bimorph element, improving the generation rate of wind, and securing the blast quantity of a specified standard. CONSTITUTION:When an a.c. voltage of 100V/50Hz, for example, is charged among a lead wire 16 and electrodes 13, 14, the piezoelectric plates 12 and 12 of a bimorph element 11 perform bending displacement 11 perform bending displacement alternately due to piezo effect, and this displacement is transmitted to the flaps 23 of a flap section 22 through clamp section 21. Such constitution that makes the bimorph element 11 performs bending displacement not only serves to reduce noise more than that of a motor drive type but also serves to improve the generation of wind because each of a plurality of the flaps 23 is oscillated at the same amplitude. And the blast quantity of a specified standard can be obtained, and the flaps 23 can be made of such simple material that branches off into a plurality. Such constitution serves cost reduction and miniaturization and keeps captioned mechanism compact.

Multilayer optical disk device

Abstract: PURPOSE:To obtain high track traceability, by controlling a deflection angle by a polarizing body using a bimorph type piezoelectric driving element, or a laminated ceramics driving element CONSTITUTION:By setting an arm 22 by the bimorph type piezoelectric driving element in which an electrode 222 is sandwiched by electrostrictive elements 221 and 221', and impressing a voltage between the electrode evaporated on the surfaces of the electrostrictive elements 221 and 221', and the electrode 222 by conductors 30 and 31, the bimorph type piezoelectric driving element is deformed being attached a directional characteristic, by the polarity of the voltage In other words, it is possible to drive a polarizing body 21 in up and down, by controlling the polarity, and the size of an impressing voltage, and to control the angle of polarization of a laser beam by the voltage impressed on the bimorph type piezoelectric driving element At this time, the same effect can be obtained by using the laminated ceramics driving element

New monolithic actuators, 'monomorphs', using semiconductive ferroelectrics.

Abstract: A New actuator device is proposed using semiconductive ferroelectric ceramics. This device is a single-plate actuator capable of bending equivalently to a bimorph. A significant difference is simple structure named as a “monomorph” as compared with a multi-stacked type in the bimorph. The bend in the monomorph device is realized by non-uniform electric field distribution in the piezoelectric ceramics, through the semiconductor-metal contact effect (Schottky barrier). The monomorph has been demonstrated in the solid solutions PbZrO3-(K1/2Bi1/2)ZrO3 and BaTiO3-Dy2O3. Both systems reveal the tip deflectionof several hundred micrometers in a 0.5mm thick plate.

Optical path conversion switch

Abstract: PURPOSE:To obtain an optical path conversion switch which operates at a relatively high speed, has small variation in surrounding environment and time, and can be integrated by using a bimorph material of a transparent dielectric and performing optical path conversion by changing incidence and projection positions of light passing through the dielectric by utilizing displacement based upon voltage application CONSTITUTION:Light entering the bimorph material 7 from the 1st optical fiber 8 is guided into the 4th optical fiber 9 The 2nd optical fiber 10 and the 3rd optical fiber 11, and the 5th optical fiber 12 an the 6th optical fiber 13 are arranged on the input and output sides of the bimorph material 7 at positions corresponding to the specific bending displacement of the bimorph, and when the bimorph 7 is displaced, the waveguide in the bimorph 67 is coupled with some of those optical fibers 10-13 Then, a specific voltage is applied to respective electrodes of the input side and (or) output side of the bimorph, which is bent and displaced as specified to perform optical path conversion between three input-side optical paths and three output-side optical paths

Piezoelectric driving type transport apparatus

Abstract: PURPOSE:To improve the transport efficiency by forming a low rigidity part by connecting the part between an elastic plate and a transport body by a connecting plate formed by laminating thin plates and reducing the load applied onto a vibrating body and increased the vibration amplitude of a vibrating body and a transport body. CONSTITUTION:A piezoelectric element 24 is driven by the ac voltage having the frequency equal to the characteristic frequency of the vibration system, and a carrier body 26 is vibrated in the slantly vertical direction by the vibration, and a transported article 27 is transported in the direction of arrow 33. Since an elastic plate 23 has a connecting plate 30 formed by laminating thin plates, the angle between a bimorph 22 and a trough 26 which varies with the vibration varies largely by the smooth and arcuate deformation of the connecting plate 30. Therefore, the degree of the application onto the piezoelectric element 24 of the load which is caused by said angular variation reduces markedly, and the amplitude of the piezoelectric element 24 is increased. Therefore, the transport speed and transport efficiency of the trough 26 can be improved.

Piezoelectric type actuator

Abstract: PURPOSE:To improve the displacing speed of a piezoelectric type actuator by using as a driving piezoelectric element a transversal effect piezoelectric element such as a bimorph CONSTITUTION:A piezoelectric type actuator is composed by securing both ends of a driving transversal effect piezoelectric element 5 to clamping piezoelectric elements 6, 7 A rodlike member 8 is penetrated through the elements 6, 7, which clamps the member 8 by energizing the elements The element 5 is bent by energizing As a result, the actuator bendably tilts by energizing the elements 5-7 to relatively move to the member 8 Thus, a large displacement can be obtained by bending the element 5, and the structure can be simplified

Piezoelectric driving conveyor

Abstract: PURPOSE:To always maintain the vibration amplitude of a conveying body at constant for obtaining the constant conveying speed so as to prevent the lowering of the conveying efficiency, by providing a vibration detecting piezoelectric element for outputting voltages in response to the vibration amplitude of the conveying body, on the surface of a vibrator driving piezoelectric element. CONSTITUTION:When a lot of articles are stored in a conveying body 16, and thereafter an AC voltage is applied to piezoelectric elements 15, 16 for driving a bimorph (vibrator) 13, the bimorph 13 is permitted to vibrate so that articles in the conveying body 16 are discharged from an outlet along a conveying path 18 one by one. The quantity of the articles in the conveying body 16 is reduced with the elapse of time, a load applied to the bimorph 13 is gradually reduced so as to increasing the vibration amplitude of the bimorph 13, thereby the vibration amplitude of a vibration detecting piezoelectric element 19 mounted on the surface of the bimorph 13 is increased. And, when the generated voltage is increased, the voltage applied to the piezoelectric elements 15a, 15b is controlled to be lowered by a vibration control circuit 27 so that the vibration amplitude of the conveying body 16 is restored, Therefore, it is possible to always maintain the conveying speed at constant.

Bimorph-using focus adjuster and exposure controller

Abstract: PURPOSE:To perform continuous focus adjustment with a simple constitution, by driving a photographing lens by utilizing a bimorph and controlling the voltage impressed across the bimorph by comparing the voltage with the voltage of an analog memory corresponding to the distance to an object. CONSTITUTION:When switches S1 and S2 are turned on and a comparator COMP outputs a high level, the output of an ANd circuit AN1 becomes a high level. As a result, a transistor (TR) Q1 is turned on and a base current is made to flow to another TR Q2, and thus, the TR Q2 is also turned on. When the TR Q2 is turned on, a voltage V2 which is boosted at a booster circuit 14 is impressed across a bimorph 4. As the voltage is impressed, electric charges are accumulated in a capacitor C2 and the voltage impressed across the bimorph 4 is boosted. When the voltage impressed across the bimorph 4 is boosted, the bimorph 4 is deformed and, at the same time, voltages divided by resistances R2 and R3 are also boosted. When the divided voltages become equal to the voltage of a capacitor C1 for memory, the output of a comparator circuit 6 is inverted and both the TRs Q1 and Q2 are turned off and power supply to the bimorph 4 is stopped.

Bimorph-type piezoelectric device

Abstract: PURPOSE:To obtain a bimorph-type piezoelectric device having a function of actuators in combination with functions of sensors for measuring external forces and for measuring displacement, by providing a piezoelectric element having a voltage application controlling means for causing displacement by piezoelectric effects and a piezoelectric element having means for measuring the displacement as an output voltage CONSTITUTION:A bimorph-type piezoelectric device is constituted by a plurality of a plurality of piezoelectric elements, namely by a piezoelectric element 1 having voltage application control means 9 for causing displacement by piezoelectric effects and a piezoelectric element 1' having means 5 for determining the dislocation of said piezoelectric element 1 as an output voltage For example, two piezoelectric elements 1 and 1' are joined to each other through a common electrode 3, and a potential difference is produced between an electrode 4 formed on the surface of the piezoelectric element 1 and the common electrode 3 by a voltage- controlled power supply 9 so as to obtain displacement in bend due to expansion or shrinkage of the piezoelectric element 1 The piezoelectric element 1' is connected to a voltage measuring circuit 5 for measuring a potential difference produced by polarization between the electrode 4' and the common electrode 3 due to the expansion or shrinkage of the piezoelectric element 1 A voltage-distortion characteristic curve obtained when the piezoelectric elements 1 and 1' are unloaded is stored in ROM's 10 and 11

Piezoelectric linear motor

Abstract: PURPOSE:To increase movement, and to enable operation at high speed by driving a piezoelectric linear motor by utilizing deflection deformation or torsion deformation by a piezoelectric element. CONSTITUTION:A piezoelectric linear motor is constituted of two shafts 10, 12 disposed in parallel, shift clamp sections 14, 16, which are each mounted to the shafts 10, 12 and freely expanded or shrunk independently, and a piezoelectric bimorph element 18 connecting the clamp sections. Consequently, the bimorph element 18 is deflected and deformed in the direction corresponding to the polarity of voltage having predetermined polarity when the voltage is applied to the bimorph element 18, and the bimorph element is returned to an original state when the application of the voltage is released. Accordingly, deflection deformation drives the shaft clamp sections 14, 16 in the axial direction, and can move them.

Remote controlling box of air conditioner and the like

Abstract: PURPOSE:To eliminate the deterioration in detection accuracy with installation conditions, to increase the degree of freedom of installation and to improve the reliability and service life of an apparatus by a method wherein air flow produced by the vibration of the free end of a bimorph element, of which mechanical resonance is developed by applying voltage through the film of the bimorph element, is sent to a temperature detecting means and a control device. CONSTITUTION:A thermistor 3, which acts as a temperature detecting means, is arranged near the free end 12' of a bimorph element 12, which produces air flow by moving like a fan through the application of AC voltage thereon. The air flow produced in a case 1 circulates ambient air by sucking through air influx ports 6. By sending an air flow which is produced by means of the mechanical resonance of the bimorph element 12 provided within the case 1 of a remote controlling box, not only the effect of the change of the detected temperature by the convection of the air from outside depending on the installation condition of the remote controlling box is hard to be exerted but also the detection accuracy of the remote controlling box can be improved.

Fine adjustment device for micromanipulator

Abstract: PURPOSE:To improve the moving smoothness and the responsiveness and then to improve the positioning accuracy and the reproducibility with the titled adjustment device, by using a displacement member to the fine adjustment device for micromanipulator of a microscope with piezoelectric ceramics combined into a bimorph structure. CONSTITUTION:The output of a distortion gauge S bonded to a bimorph displacement member 1, 2, 3 or 3' is fed back to the displacement target signal of the bimorph displacement member attached to the gauge S via a distortion amplifier 21. Then the difference signal is converted into the operational signal of an impression voltage generator 23 which produces the voltage to be applied to said displacement member by a P.I.D 22. Thus the desired displacement is always given to those members 1-3' by said feedback action.

Dual-operation type piezoelectric bimorph actuator

Abstract: PURPOSE:To prevent deterioration of performance of displacement and yielding force, by forming two sets of facing electrodes, which independently displace both ends of elements in the longitudinal direction, in point or line symmetry, and providing a through hole for turning an actuator with a fixing part as a center, in the thickness direction of a bimorph element. CONSTITUTION:Silver 17 is metallized on an upper surface and a back surface of a piezoelectric ceramic plate 14. The two piezoelectric ceramic plates 14 are bonded to a brass plate 15 having equal width and length. Supporting plates 11 are attached to the center in the longitudinal direction. Thus a piezoelectric bimorph actuator 20, whose center is fixed, is obtained. A hole 13 is provided at the center of the supporting plates 11 so that a rotary center shaft can be attached. The silver electrodes 17 are divided into two parts. Both ends of the elements 10 can be displaced, with the supporting plates 11 as fixing ends.