Showing papers on "Bimorph published in 1986"

Ink-jet recording apparatus

Abstract: An ink-jet recording apparatus includes a film having a number of holes for holding ink. The film is driven in a predetermined direction near a recording paper. Ink is supplied to the holes by an ink supply mechanism. Ink in desired holes are heated by a thermal head to be ejected onto the recording paper. The thermal head is supported by a bimorph cell. In accordance with a voltage supplied from a voltage generator, the bimorph cell exponds or contracts to move the thermal head between a first position wherein the thermal head is adjacent to the recording paper and in contact with the film and a second position wherein the thermal head is separated from the recording paper and film.

Influence of the vibrating system of a multipinhole‐plate ultrasonic nebulizer on its performance

Abstract: A multipinhole‐plate ultrasonic atomizer was experimentally optimized, employing a bender bimorph vibrator structure made up of a thin pinhole plate and a circular ring piezoelectric element. Effects of the vibration mode upon the performance were studied in terms of the sound pressure generation and the behavior of bubbles caused by cavitation. The performance was also examined with regard to the number of pinholes and the shape of the pinhole plate. As a result, the atomizer was proved to be able to jet and nebulize ordinary liquid most efficiently by the second harmonic vibration mode if the vibrating system is supported along the circumference of the ring piezoelectric element. It was also proved that the maximum atomizing rate is approximately proportional to the number of pinholes and that the spray pattern can easily be controlled by changing the shape of the pinhole plate.

Pacing lead with piezoelectric power generating means

Abstract: The pacing lead includes a catheter distal end portion which has a piezoelectric device therein and which is adapted to be inserted into a human heart. The device can be a ceramic bimorph or can be made of polyvinylidene fluoride film for generation of electrical energy upon contraction of the heart. The piezoelectric device is designed to generate electrical energy in response to movement of the implanted pacing lead and in the preferred embodiment is incorporated into the wall of the catheter of the lead as a longitudinal or spiral configured strip of film having piezoelectric properties.

Piezoelectric relay switching circuit

Abstract: To control the operation of a piezoelectric relay, control circuitry is disclosed for direct ohmic connection to a utility AC source to draw the minimal power required to actuate the relay's bimorph member pursuant to selectively switching power current through either one of two separate loads. The control circuitry, which is largely implimented in a single integrated circuit chip, utilizes isolating resistance and the capacitances of a voltage doubler circuit and the piezoceramic plate elements for transient suppression and circuit protection.

Parts feeding apparatus of the piezoelectric drive type

Abstract: A parts feeding apparatus of the piezoelectric drive type consists of a base, a plurality of bimorph cell assemblies each including a leaf spring the lower end of which is fixed to the base and two piezoelectric elements each fixed on respective sides of each leaf spring to vibrate each leaf spring when AC voltage is applied to the piezoelectric elements, and a conveyor connected with the lower end of each connecting member. Furthermore, the upper end of each bimorph cell assembly is connected with the lower end of each connecting member so that the vibration of each bimorph cell assembly is transmitted to the conveyor to feed articles placed on it. Each connecting member has lower bending stiffness than each leaf spring by forming one or more semicircular cut-out portions in it or selecting its thickness or its material so that an external force acting on each piezoelectric element in vibration is decreased.

Piezo-electric fan type blower

Abstract: PURPOSE: To increase a wind amount by transmitting vibration generated by a piezo-electric bimorph element to a rotary vibrator as a rotor mounting a plurality of vibrating plates. CONSTITUTION: A bimorph element mounting member 9 for mounting the fixed side base of a piezo-electric bimorph element 1 on a casing is provided on the central portion of a pair of side end edges of the lower side casing plate 2. A rotary vibrator 5 provided with a vibrating plate 8 is rotatably fitted onto a rotary shaft 6. The vibration of said element 1 is transmitted to said vibrator 5 and each vibrating plate 8 so that air introduced from a fixed end region is pushed out to the free end. Thus, while small number of said elements is used, a large amount of wind can be provided. COPYRIGHT: (C)1987,JPO&Japio

Electronic part device

Abstract: PURPOSE:To cool an electronic-part package effectively, by attaching cooling means utilizing bimorph vibrators and the like to the package, in which electronic circuits are packaged as a unitary body CONSTITUTION:A package main body 1 is constituted by a ceramic base 11, on which a semiconductor element 2 is mounted, and a ceramic cap 12 An inverted L type ceramic supporting stage 5 is bonded to the outside of the base 11 with a bonding agent such as epoxy resin so that thermally good conductivity is obtained Piezoelectric elements 71 and 72 are stuck to both surfaces of vibrating plates 6 and bimorph vibrators are formed Two cooling fans 8 having said structure are fixed to the stage 5 so that the package 1 is cooled from the upper part of the package 1 When an AC voltage is applied to the bimorph vibrators, the tip parts of the fans 8 are vibrated Thus the surfaces of the base 11 is effectively cooled

Method and apparatus for controlling a bimorph leaf which supports a deflectable head

Abstract: An apparatus for controlling a deflectable head mounted on a bimorph leaf having a detector connected to the latter for detecting a deflection of the bimorph leaf, a drive signal generating circuit for generating a drive signal to deflect the bimorph leaf in response thereto, a combining circuit for combining output signals of the detector and the drive signal generating circuit, a damping signal generating circuit for generating a damping signal to attenuate a distortion of the bimorph leaf that is produced by the deflection of the bimorph leaf, a signal producing circuit for generating a signal corresponding to a variation of the detector that remains after application of the damping signal to the bimorph leaf, and a circuit connected between the signal producing circuit and the combining circuit for compensating and thereby reducing the signal corresponding to the remaining variation of the detector.

Piezoelectric laser scanner

Abstract: A piezoelectric bimorph scanner is disclosed which has a flexural beam (36) attached to the free end of a cantilever-mounted piezoelectric bimorph crystal (40) A mirror (55) is bonded to the flexural beam at a predetermined distance from the bimorph crystal An AC voltage of predetermined frequency is applied to the bimorph crystal causing the flexural beam to oscillate, with a node at the center of the mirror The mirror oscillates about the node rather than swinging in an arc, enabling the scanner to deflect a collimated light beam over a larger deflection angle than heretofore possible without additional light beam control apparatus In an alternative embodiment, a laser diode may be mounted on the flexural beam instead of the mirror, further reducing costs and components

Piezo-electric pump

Abstract: PURPOSE:To provide a small and low volume piezo-electric type pump, by a method wherein pumping motion is effected through bending deformation of a bimorph type piezo-electric vibrating plate. CONSTITUTION:A vibrating plate 2 is located to the one end of a pressurizing chamber 1 of a pump, and a bimorph type piezo-electric material 3 is situated to the outer wall of the vibrating plate 2. Meanwhile, a suction port 4 and a discharge port 5 are formed in a pressurzing chamber 1 on the opposite side to the vibrating plate 2, and a suction valve 6 and a discharge valve 7 are located to the suction port and the discharge port, respectively. A voltage is intermittently applied on the bimorph type piezo-electric material 3 to actuate the vibrating plate 2 for pumping motion.

Accurate displacement driver

Abstract: PURPOSE:To attain a minute displacement with high accuracy by constituting a drive unit with the 1st piezoelectric element having a thickness-shear slip mode and the 2nd piezoelectric element which bends in the direction approximately rectangular to the 1st piezoelectric element with the bimorph behavior. CONSTITUTION:A drive unit is provided with the 1st piezoelectric element 30 having a thickness-shear slip mode capable of a displacement toward an axis X and the 2nd piezoelectric element 31 which bends with the bimorph behavior capable of a displacement toward an axis Z. The element 30 is adhered approximately at the center of the element 31 and an adaptor 33 is adhered on the opposite side of the element 30 to the side where the element 31 is adhered in order to transmit the movements of both elements 30 and 31 to an object to be driven. While the both ends of the element 31 of a bimorph form containing tow sheets of rectangular elements bonded to each other are fixed to a base via support blocks 32.

Printing head for wire dot printer and its preparation

Abstract: PURPOSE:To prevent the generation of the complicatedness of manufacturing and the irregularity in performance, by integrally forming a plurality of bimorph type electrostriction elements arranged in an almost fan shape and the wires arranged at the central point of a conductive metal substrate by utilizing photolithographic technique. CONSTITUTION:On the same circles of a conductive metal substrate 1 at the same position on both surfaces of said substrate 1, a plurality of bimorph type electrostriction vibrators 11 are integrally formed in a fan or almost equilateral triangular shape of which the apex is directed to the center by using screen printing or photolithography. Next, the punching of an outer shape, the separation of the electrostriction elements 11 at every element unit and the formation of wires 13 are simultaneously performed by photoetching or punching so as to leave necessary parts. Subsequently, the parts of wires 13 are bent and erected at almost right angles to the surface of each electrostriction element 11. Because the bimorph electrostriction elements 11 radially arranged on the concentric circle and the wires arranged at the center point of the substrate 1 are integrally formed as mentioned above, a large number of printing heads can be manufactured at once and no irregularity in capacity is generated.

Monolithic Bimorph with Internal Electrodes

Abstract: Monolithic bimorphs with internal electrodes which are composed of two, three and four layers were made from the high d31 material of a modified Pb(Ti, Zr)O3. The new bimorphs utilized unstiffened mode and were used as large-displacement transducers under low DC bias. Those bimorphs with four layers generate displacement of up to 0.6 mm at a voltage of 30 V with 4 msec response. The force induced by the DC bias was in proportion to the bias. Hysteresis of the displacement became smaller by introducing an intermediate layer or internal Pd electrodes.

Vibration detecting device

Abstract: A vibration detection device comprises a piezoelectric element 10 in the form of a bimorph strip and a mechanical contact mass which may be a ball 38. Movement of one or other of the element and mass arising from a vibration to be detected at a surface 12 is opposed by the inertia of the other one of the element and the mass, thereby to induce a deformation in the element and generate an output signal. A spring 40 may be provided to locate the ball 38 and, if desired, to supplement the inertia thereof. Movement of lid 36 of the housing can adjust the spring force and therefore the sensitivity of the device. The strip 10 may be supported on a wire bridge 14 to increase the bending moment induced therein. Application to intruder alarms is described.

Electrically controllable fibre-optic switch

Abstract: The previously known electrically controllable, mechanical fibre-optic switches (so-called fibre-optic relays) use an electromagnet as electromechanical drive. This entails a relatively high electric power requirement of 100-700 mW and leads to slow switching operations of 10-30 ms. The novel fibre-optic relay is to be distinguished by a low operating power and short switching times. Use is made as electromechanical drive of a piezoelectric bimorph strip which bends when an electric voltage is applied and can thus position optical fibres in a pinpointed manner. Since a freely oscillating bimorph strip indicates a strongly oscillating transient response, additional magnetic damping of the movement was undertaken through the use of stops, which consist partly of permanently magnetic material, and of corresponding metal parts on the strip. In order to prevent so-called creep effects in the piezoelectric material, the bimorph strip is driven not by a step voltage function, i.e. two voltage values (e.g. 0 V, 200 V), but by means of a function which decays from a short-term peak value to a lower end value (e.g. 0 V, 200 V = > 120 V) which is obtained with the aid of a low-loss voltage transformer integrated in the relay. The values obtained with a prototype yield a power requirement of 15 mW (5 V/3 mA) for switching times of < 3 ms. Electrically controllable... Original abstract incomplete.

Methods of and apparatus for controlling a bimorph distortion detection device

Abstract: not available for EP0197663Abstract of corresponding document: US4663555An apparatus for controlling a deflectable head mounted on a bimorph leaf having a detector connected to the latter for detecting a deflection of the bimorph leaf, a drive signal generating circuit for generating a drive signal to deflect the bimorph leaf in response thereto, a combining circuit for combining output signals of the detector and the drive signal generating circuit, a damping signal generating circuit for generating a damping signal to attenuate a distortion of the bimorph leaf that is produced by the deflection of the bimorph leaf, a signal producing circuit for generating a signal corresponding to a variation of the detector that remains after application of the damping signal to the bimorph leaf, and a circuit connected between the signal producing circuit and the combining circuit for compensating and thereby reducing the signal corresponding to the remaining variation of the detector.

Bimorph type piezo actuator

Abstract: PURPOSE:To minimize sliding parts by sealing a bimorph type piezo actuator in casings. CONSTITUTION:An electrical strain element 1 is formed as a board of bimorph type electrical strain elements. A bimorph type piezo actuator is comprised of the electrical strain element 1 and a voltage applying plate 13. Contact plates 17, 18 connected respectively with conductors 15, 16 are fixed in casings 3a, 3b, and the free ends of the contact plates 17, 18 are formed in curved shape to be pressed on the voltage applying plates 13, 14 owing to their elasticity when the casings 3a, 3b are fixed. An elastic plate 2 is bent by means of the bimorph type electrical strain element 1 when the voltage is applied to the voltage applying plate 13 or 14 to move a valve body 5 variably to either of positions for seating it at a valve seat 7 or 9.

Bimorph piezoelectric vibrator unit

Abstract: PURPOSE:To facilitate handling and to enhance mechanical reliability by forming a piezoelectric actuator in a unit structure for enclosing a piezoelectric element with a lower housing and an upper cover. CONSTITUTION:A bimorph actuator unit 100 is formed of a bimorph element 1, a substrate 2, a mount 3, a cover case 4, a displacement restricting mechanism 5, an operating force transmitter 9, a fluctuation restricting mechanism 11 of a rod 9. The element 1 is secured at one end 1a on the mount 3 provided on the substrate 2, becomes at the other end a movable end 1b, is coated by a cover case 4 at the top to restrict the element 1 by a projection 5b. Thus, the polarity is converted by a drive circuit to apply a voltage, thereby elevationally vibrating the element 1 in a rupture limit. The end 1b is engaged with the end 9a of the rod 9 to drive the transmitter 8.

Piezoelectric element driving device

Abstract: PURPOSE:To control exactly a displacement quantity of a piezoelectric element by detecting the displacement quantity of the piezoelectric element, feeding back this value and displacing the piezoelectric element to a prescribed position. CONSTITUTION:A signal for displacing a bimorph 10 by a prescribed quantity is outputted from a signal source 11. A driving voltage detecting circuit 18 detects a driving voltage. Also, a resistance 14 detects a driving current, and outputs it to an integration circuit 16. The circuit 16 outputs a value corresponding to a total charge which has been accumulated in the bimorph 10. A subtraction circiut 20 subtracts an output signal value of the circuit 18 from an output signal value of the circuit 16 and derives an actual displacement quantity of the bimorph 10. Subsequently, this value is fed back to a driving circuit 13 through a phase compensating circuit 22. Therefore, the displacement quantity of the bimorph 10 is controlled so as to become a prescribed value. In this way, the displacement quantity of the bimorph 10 can be controlled exactly.

Comparison of deformability between multilayered deformable mirrors with a monomorph or a bimorph actuator.

Abstract: An exact formulation is made for the radii of curvature obtainable by the two kinds of multilayered deformable mirror with either a monomorph or a bimorph actuator. They are then compared to derive a criterion for superiority in deformability. Numerical studies mainly show that the PVDF piezoelectric film, for example, is suitable for use as a monomorph actuator while the PZT piezoelectric ceramic is better as a bimorph actuator. Experimental results are also given to validate theoretical and numerical analyses.

An optical switch or sensor

Abstract: An optical switch or sensor may be formed from a single bimorph member bimetallic strip or bimagneto strictive which is formed with a slot 9 which divides it into two parts. A mounting member is moulded on to the free ends of each bimorph part and may be divided into two by the same slot as divides the two parts of the bimorph. Optical fibres 16 may be located in grooves on the mounting member. In operation signals are applied to the bimorph parts so as to make them bend simultaneously in opposite directions. The amount of movement may be limited by the widths of saw-cuts 14 so as to ensure that in each switching position the optical fibres line up with each other.

Auto-focus device

Abstract: PURPOSE:To reduce the size and weight of a device and to obtain a lens provided with an automatic focusing device with minor modification, by holding a solid-state image pickup element vertically against the light axis of the lens, vibrating the element, detecting the minute sharpness signal of the element, and making it possible to adjust the focus automatically. CONSTITUTION:A bimorph 23 is driven by an AC current of a bimorph driving circuit 35 and is vibrated vertically toward the light axis 40 of a lens 21. Therefore, a solid-state image pickup element 22 vibrates toward the direction of the light axis 40 holding the pickup surface vertically against the light axis 40. Then a blur occurs. A blur detection circuit 36 detects this blur and calculates the most proper focus position, and rotates a focusing ring 38 in the focus direction by driving a focus motor 32. Furthermore, the circuit 32 (?) again detects the blur and instructs a drive circuit 35 to control the amplitude of the bimorph 23. By repeating the above procedure, the focus is set at the most proper position.

Blower using piezo-electric bimorph vibrating plate

Abstract: PURPOSE:To prevent the generation of vibration and noise, by alternately providing a piezo-electric bimorph vibrating plate and a piezo-electric bimorph vibrating plate, displaced in a reverse direction to the former said vibrating plate, to be arranged in an equal number of sheets and lined with a supporting frame while cancelling reaction force, generated in said supporting frame, as a whole CONSTITUTION:Plural sheets of piezo-electric bimorph vibrating plates, consisting of a piezo-electric bimorph vibrating plate 1 and a vibrating plate 1' displaced in a reverse direction to said vibrating plate 1, are provided to be lined on a supporting frame 3, further a number of sheets of the vibrating plates 1 are substantially equalized to that of the vibrating plates 1' In order to obtain a mode arranging in every sheet the vibrating plates 1 and 1' displaced in a reverse direction to each other, the vibrating plate 1 is constituted from a piezo-electric unit 1a, having a polarization direction equal to the electric field direction, and a piezo-electric unit 1b, having said both directions being opposite, but the neighboring vibrating plate 1', arranging in the respectively opposed surface a piezo-electric unit of identical kind to be positioned, that is, the unit so as to be both the piezo-electric units 1a or 1b, is provided to be lined on the supporting frame 3 In this way, vibration and noise can be prevented by cancelling reaction force generated in a curved direction and an opposite direction in a supporting fixture 2

Piezoelectric displacement element

Abstract: PURPOSE:To prevent a mechanical failure in a piezoelectric displacement element by a method wherein the end surfaces of the second electrodes on the sides nearer the supporting member are placed at positions away from the sides of the points of the first electrodes at the prescribed distance from the supporting member and the effect of electric strain is given more to the sides of the points than to the supporting point. CONSTITUTION:Whole surface electrodes 6 are respectively provided on the laminating surfaces of two sheets of piezoelectric elements 5 and pattern electrodes 7 are respectively provided on the other exposing surfaces of the piezoelectric elements 5. This piezoelectric displacement element is made into one in the bimorph structure, wherein two sheets of the piezoelectric elements 5 are pasted together in a parallel type using a bonding agent for taking largely the displacement, a supporting member 8 consisting of a conductive metal and so forth is used as the cantilever beam and a video heat 9 is attached to the point of the piezoelectric displacement element. A lead electrode 7a of the width (w) of 1/2 of the width W of the piezoelectric elements or less than the 1/2 is integrally provided in one body with the pattern electrodes 7 on the piezoelectric elements 5 on the same conditions as those that the pattern electrodes 7 are provided on the piezoelectric elements 5 as the lead extending over from the pattern electrodes 7 to the supporting member 8.

Actuator for driving head

Abstract: PURPOSE:To simplify manufacturing and to reduce its cost by forming cross- finger type electrodes on the surface of an electrostrictive element body and polarizing and/or driving them, and utilizing the lateral or longitudinal effect of the electrostrictive element, and obtaining the same driving operation with a bimorph element. CONSTITUTION:Electrodes P1 and P2 are formed on the electrostrictive element 4 during polarization by vapor deposition or baking, and connected to a high voltage source B and polarized; and the electrodes P1 and P2 for polarization are removed by etching and electrodes P3 and P4 are formed similarly on the electrostrictive element 4 during driving. Flexural oscillation is caused in the direction of an electric field in the electrostrictive element 4 by the electrodes P3 and P4 for driving because the polarizing direction and applied voltage direction cross each other at right angles. Consequently, the electrostrictive element which has a better excitation characteristic than a bimorph oscillator is obtained as the driving actuator of VTR, and the structure is simple, so variance in characteristic is small and the manufacture process is simplified, reducing the cost.

Piezoelectric type displacement device

Abstract: PURPOSE:To enable displacement in the direction of rotation by piezoelectric action by fixing a magnetic head, etc. at the free end of a bimorph plate in which piezoelectric elements electrically polarized in the directions different in at least two regions are laminated. CONSTITUTION:Piezoelectric elements 7, 9 forming a bimorph plate 3 are divided into two regions A, B in the width direction in a boundary surface l vertical to element surfaces along the longitudinal direction, the directions of electric polarizing axes 7a, 9a and 7b, 9b are reversed mutually along the thickness direction, and the elements 7, 9 are bonded by metallic electrodes 6b, 8b. When electrodes 6a, 8b are connected to a terminal 10a and electrodes 6b, 8a to a terminal 10b and DC voltage is applied while using the terminal 10a as a positive one and the terminal 10b as a negative one, the element 7 in the region A extends and the element 9 shrinks, and the element 7 in the region B shrinks and the element 9 extends. Since displacement in the longitudinal direction is larger than width, the free end of the bimorph plate 3 is twisted in the counterclockwise direction centering around a central axis O in the longitudinal direction, and a magnetic head 4 fixed at the center of an end surface 3a is turned in the same direction, and rotated in the clockwise direction which the polarity of voltage is inverted.

Problems with cryogenic operation of piezoelectric bending elements

Abstract: Piezoelectric bimorphs constructed from lead titanate‐zirconate (PZT) ceramic bonded to a brass sheet have been tested at cryogenic temperatures to determine their suitability for use in a low‐temperature micropositioner. Experimental data are presented on bimorph sensitivity (displacement per volt) as a function of the number of temperature cycles. Results indicate that bimorphs of this type cannot be calibrated because of irreversible changes in the bending characteristics that occur while cycling from room temperature to 4 K.

Piezoelectric type printer

Abstract: PURPOSE:To reduce the impact noise of a head, by operating the speed of a piezoelectric element from the output of a sensor in the first term of return movement and applying required voltage adjusting the speed at the time of impact to almost zero for a required time in the second term of return movement. CONSTITUTION:A pin 4-1 is formed to the leading end of an actuator 4 formed by laminating an elastomer 4-3 to a bimorph type piezoelectric element 4-2 and the electrode of the piezoelectric element 4-2 is connected to a piezoelectric control circuit 7. A signal change-over circuit 7-3 is connected to a voltage sensor circuit at the time of T2, T3 during the return movement of the actuator and voltages V2, V3 at this time are read in a control circuit 7-2 and the average speed between T2, T3 is calculated by using the interrelation predetermined from experiment. Further, the effect of the elastomer 4-3 is added to operate required braking start voltage V4, a braking start time T4 and a braking finish time T5 and the circuit 7-3 and a voltage apply circuit 7-1 are controlled to stop the actuator at a position of displacement 0.

Method of adjusting head hit of rotary magnetic head device

Abstract: PURPOSE:To enable to obtain good picture quality even when reproducing at varied speed by wrapping a head with a wrapping tape while oscillating a bimorph to attenuate slowly. CONSTITUTION:A period in which a magnetic head traces one track on a tape (at the time of high level of pulse wave, that is, t1, t2...t3) is bisected into the first half and the second half. In the first period t1 of tracing, positive.negative voltage +V1, -V1 equal to positive.negative voltage +V0, -V0 in which absolute value of titled voltage is maximum or larger than +V0, -V0 are supplied to a bimorph in the first half and second half respectively. In the next period t2 of tracing, negative.positive voltage -V2, +V2 obtained by subtracting about 25% of absolute value from negative.positive voltage -V1, +V1 are supplied to the bimorph in the first half and second half. In the next period t3, voltage is reduced by 50%, and reduced by 75% in the period t4, and in the period t5, voltage is not supplied entirely, i.e. made to the state of zero V. Thus, wrapping tape is traced by the magnetic head while supplying voltage to the bimorph.

Piezoelectric type pump

Abstract: PURPOSE:To prevent the flow rate of a pump from lowering, by forming a container for confining the outer periphery of a piezoelectric element from a material having a greater thermal expansion coefficient so that the lowering of amplitude characteristic of the piezoelectric element may be compensated when the temperature of the atmospheric temperature is lowered. CONSTITUTION:An asymmtric type BIMORPH 3 is disposed in a container 1 for a piezoelectric pump, through the intermediary of a seal member 4. This container 1 is arranged to confine the outer periphery of the asymmtric type BIMORPH 3, and is made of a material having a greater thermal expansion coefficient. Therefore, even if the atmospheric temperature lowers and the amplitude characteristic of the asymmetric type BIMORPH 3 is lowered, the container itself contracts to curve the asymmetric type BIMOPRH 3 so that the operating area thereof is increased, thereby it is possible to prevent the flow rate of the pump from lowering.