Abstract: A drive circuit (18) produces a drive signal for a pump (10) having a piezoelectric actuator (14), with the piezoelectric actuator (14) forming a part of the drive circuit (18) and serving to shape a waveform of the drive signal. The drive circuit (18) comprises a pulse generator (100) which generates pulses; a converter circuit (102) which receives the pulses and produces charge packets at a rate which equals a desired drive frequency; and, the piezoelectric actuator (14). The piezoelectric actuator (14) receives the charge packets and, by its capacitive nature, integrates the charge packets to shape the waveform of the drive signal. Preferably, the piezoelectric actuator (14) integrates the charge packets to yield a drive field that approximates a sine wave. In one non-limiting example embodiment, the pulse generator (100) comprises a microcontroller-based pulsed width modulator (PWM) circuit (116) and the converter circuit (102) comprises a flyback circuit.

Abstract: A drive circuit (18) produces a drive signal for a pump (10) having a piezoelectric actuator (14), with the piezoelectric actuator (14) forming a part of the drive circuit (18) and serving to shape a waveform of the drive signal. The drive circuit (18) comprises a pulse generator (100) which generates pulses; a converter circuit (102) which receives the pulses and produces charge packets at a rate which equals a desired drive frequency; and, the piezoelectric actuator (14). The piezoelectric actuator (14) receives the charge packets and, by its capacitive nature, integrates the charge packets to shape the waveform of the drive signal. Preferably, the piezoelectric actuator (14) integrates the charge packets to yield a drive field that approximates a sine wave. In one non-limiting example embodiment, the pulse generator (100) comprises a microcontroller-based pulsed width modulator (PWM) circuit (116) and the converter circuit (102) comprises a flyback circuit.

Abstract: A diaphragm assembly (20) comprises at least two piezoelectric diaphragm members (22) arranged in a stacking direction (23). An interface layer (24) is situated between adjacent piezoelectric diaphragm members (22). The interface layer (24) in the stacking direction (23) is displaceable and incompressible or resilient. The interface layer (24) permits lateral movement of the adjacent piezoelectric diaphragm members (22) relative to the interface layer (24) in a direction perpendicular to the stacking direction (23). The interface layer (24) can comprise, for example, an incompressible liquid or a semi-liquid or a compressible gas. A gasket (26) can be used to seal the substance in the interface layer if necessary.

Abstract: An actuator assembly comprises a first diaphragm (422) and a second diaphragm (424) connected to the first diaphragm for forming a chamber (426) between the first diaphragm and the second diaphragm. An actuator shaft (427) is connected to first diaphragm (422) and is oriented to extend through the chamber (426) and to extend through an aperture formed in the second diaphragm (424). The second diaphragm (424) can be connected to an actuator body (450) wherein the actuator shaft (427) performs an actuation operation. Alternatively, one or more actuator amplification assemblies (400(B)) can be interposed between the second diaphragm and the actuator body.

Abstract: A pump comprises a diaphragm assembly which includes a first diaphragm (22) having a first diaphragm edge (28) and a second diaphragm (24) having a second diaphragm edge (30). The first diaphragm edge (28) and the second diaphragm edge (30) are bonded together so that a bellows chamber (26) is formed between the first diaphragm (22) and the second diaphragm (24). At least one and possibly both of the first diaphragm (22) and the second diaphragm (24) is a piezoelectric diaphragm which displaces in accordance with application of an electrical signal. A driver applies the electrical signal to whichever of the first diaphragm (22) and the second diaphragm (24) is the piezoelectric diaphragm. The first diaphragm and the second diaphragm bow outwardly together and shrink in diameter during a suction stroke but flatten out and increase in diameter during a pump stroke.

Abstract: A drive circuit (18) produces a drive signal for a pump (10) having a piezoelectric actuator (14), with the piezoelectric actuator (14) forming a part of the drive circuit (18) and serving to shape a waveform of the drive signal. The drive circuit (18) comprises a pulse generator (100) which generates pulses; a converter circuit (102) which receives the pulses and produces charge packets at a rate which equals a desired drive frequency; and, the piezoelectric actuator (14). The piezoelectric actuator (14) receives the charge packets and, by its capacitive nature, integrates the charge packets to shape the waveform of the drive signal. Preferably, the piezoelectric actuator (14) integrates the charge packets to yield a drive field that approximates a sine wave. In one non-limiting example embodiment, the pulse generator (100) comprises a microcontroller-based pulsed width modulator (PWM) circuit (116) and the converter circuit (102) comprises a flyback circuit.

Abstract: A drive circuit (18) senses a parameter of a piezoelectric actuator (14) operating in a device (10) and adjusts a drive signal of the piezoelectric actuator in accordance with the parameter. The drive circuit comprises a controller (100) which controls a drive signal applied to the piezoelectric actuator (14); a feedback monitor (122) which obtains a feedback signal from the piezoelectric actuator while the piezoelectric actuator works; and, a processor (116) which uses the feedback signal to determine the parameter of the piezoelectric actuator. In one example mode, the parameter of the piezoelectric actuator which is determined by the piezoelectric actuator drive circuit is the capacitance or dielectric constant of the piezoelectric actuator. In other example modes, the parameter of the piezoelectric actuator which is determined by the piezoelectric actuator drive circuit is impedance or resonant frequency of the piezoelectric actuator.

Abstract: A drive circuit (18) senses a parameter of a piezoelectric actuator (14) operating in a device (10) and adjusts a drive signal of the piezoelectric actuator in accordance with the parameter. The drive circuit comprises a controller (100) which controls a drive signal applied to the piezoelectric actuator (14); a feedback monitor (122) which obtains a feedback signal from the piezoelectric actuator while the piezoelectric actuator works; and, a processor (116) which uses the feedback signal to determine the parameter of the piezoelectric actuator. In one example mode, the parameter of the piezoelectric actuator which is determined by the piezoelectric actuator drive circuit is the capacitance or dielectric constant of the piezoelectric actuator. In other example modes, the parameter of the piezoelectric actuator which is determined by the piezoelectric actuator drive circuit is impedance or resonant frequency of the piezoelectric actuator.

Abstract: A drive circuit (18) produces a drive signal for a pump (10) having a piezoelectric actuator (14), with the piezoelectric actuator (14) forming a part of the drive circuit (18) and serving to shape a waveform of the drive signal. The drive circuit (18) comprises a pulse generator (100) which generates pulses; a converter circuit (102) which receives the pulses and produces charge packets at a rate which equals a desired drive frequency; and, the piezoelectric actuator (14). The piezoelectric actuator (14) receives the charge packets and, by its capacitive nature, integrates the charge packets to shape the waveform of the drive signal. Preferably, the piezoelectric actuator (14) integrates the charge packets to yield a drive field that approximates a sine wave. In one non-limiting example embodiment, the pulse generator (100) comprises a microcontroller-based pulsed width modulator (PWM) circuit (116) and the converter circuit (102) comprises a flyback circuit.

Abstract: A diaphragm assembly (20) comprises at least two piezoelectric diaphragm members (22) arranged in a stacking direction (23). An interface layer (24) is situated between adjacent piezoelectric diaphragm members (22). The interface layer (24) in the stacking direction (23) is displaceable and incompressible or resilient. The interface layer (24) permits lateral movement of the adjacent piezoelectric diaphragm members (22) relative to the interface layer (24) in a direction perpendicular to the stacking direction (23). The interface layer (24) can comprise, for example, an incompressible liquid or a semi-liquid or a compressible gas. A gasket (26) can be used to seal the substance in the interface layer if necessary.

Abstract: A drive circuit (18) senses a parameter of a piezoelectric actuator (14) operating in a device (10) and adjusts a drive signal of the piezoelectric actuator in accordance with the parameter. The drive circuit comprises a controller (100) which controls a drive signal applied to the piezoelectric actuator (14); a feedback monitor (122) which obtains a feedback signal from the piezoelectric actuator while the piezoelectric actuator works; and, a processor (116) which uses the feedback signal to determine the parameter of the piezoelectric actuator. In one example mode, the parameter of the piezoelectric actuator which is determined by the piezoelectric actuator drive circuit is the capacitance or dielectric constant of the piezoelectric actuator. In other example modes, the parameter of the piezoelectric actuator which is determined by the piezoelectric actuator drive circuit is impedance or resonant frequency of the piezoelectric actuator.

Abstract: Actuator assemblies comprise an actuator element and two piezoelectric assemblies, with the two piezoelectric assemblies being configured and arranged for controlling movement of the actuator element. In some example implementations, the first piezoelectric assembly and the second piezoelectric assembly are constructed and arranged so that a temperature dependency of the first piezoelectric assembly is cancelled by the temperature dependency of the second piezoelectric assembly. In a first example embodiment, a first piezoelectric assembly comprises a first or main piezoelectric diaphragm connected to the actuator element for displacing the actuator element in response to displacement of the first piezoelectric diaphragm. The first piezoelectric diaphragm and the second piezoelectric diaphragm are fixedly mounted to a movable carriage.

Abstract: An actuator assembly comprises a first diaphragm (422) and a second diaphragm (424) connected to the first diaphragm for forming a chamber (426) between the first diaphragm and the second diaphragm. An actuator shaft (427) is connected to first diaphragm (422) and is oriented to extend through the chamber (426) and to extend through an aperture formed in the second diaphragm (424). The second diaphragm (424) can be connected to an actuator body (450) wherein the actuator shaft (427) performs an actuation operation. Alternatively, one or more actuator amplification assemblies (400(B)) can be interposed between the second diaphragm and the actuator body.

Abstract: A diaphragm assembly (20) comprises at least two piezoelectric diaphragm members (22) arranged in a stacking direction (23). An interface layer (24) is situated between adjacent piezoelectric diaphragm members (22). The interface layer (24) in the stacking direction (23) is displaceable but incompressible. The interface layer (24) permits lateral movement of the adjacent piezoelectric diaphragm members (22) relative to the interface layer (24) in a direction perpendicular to the stacking direction (23). The interface layer (24) can comprise, for example, an incompressible liquid or a semi-liquid. A gasket (26) can be used to seal the incompressible substance in the interface layer if necessary.

Abstract: An electrically driven actuator (20, 120) comprises a deformable member (22, 122) which deforms as a function of applied voltage. A coupler (30) connects the deformable member to a shaft (40, 140) which, depending on embodiment and mode of operation, may be either displaceable along its axis or stationary. A controller (50, 150) actuates the deformable member by applying voltage in a manner to cause the coupler, as a function of applied voltage, either to engage or slip relative to the shaft, thereby causing relative displacement of the shaft and the deformable member. In one embodiment and mode of operation, the shaft (40) is displaceable and comprises an actuator element, whereas in another embodiment and mode of operation the deformable member (122) comprises the moveable actuator (121). Preferably, the controller actuates the deformable member to cause linear relative displacement of the shaft and the deformable member.

Abstract: Actuator assemblies comprise an actuator element and two piezoelectric assemblies, with the two piezoelectric assemblies being configured and arranged for controlling movement of the actuator element. In some example implementations, the first piezoelectric assembly and the second piezoelectric assembly are constructed and arranged so that a temperature dependency of the first piezoelectric assembly is cancelled by the temperature dependency of the second piezoelectric assembly. In a first example embodiment, a first piezoelectric assembly comprises a first or main piezoelectric diaphragm connected to the actuator element for displacing the actuator element in response to displacement of the first piezoelectric diaphragm. The first piezoelectric diaphragm is mounted to a movable carriage. A second piezoelectric diaphragm, which comprises the second piezoelectric assembly, is connected to the carriage for displacing the carriage in response to displacement of the second piezoelectric diaphragm.

Abstract: A pump comprises a diaphragm assembly which includes a first diaphragm (22) having a first diaphragm edge (28) and a second diaphragm (24) having a second diaphragm edge (30). The first diaphragm edge (28) and the second diaphragm edge (30) are bonded together so that a bellows chamber (26) is formed between the first diaphragm (22) and the second diaphragm (24). At least one and possibly both of the first diaphragm (22) and the second diaphragm (24) is a piezoelectric diaphragm which displaces in accordance with application of an electrical signal. A driver applies the electrical signal to whichever of the first diaphragm (22) and the second diaphragm (24) is the piezoelectric diaphragm. The first diaphragm and the second diaphragm bow outwardly together and shrink in diameter during a suction stroke but flatten out and increase in diameter during a pump stroke.

Abstract: A drive circuit (18) produces a drive signal for a pump (10) having a piezoelectric actuator (14), with the piezoelectric actuator (14) forming a part of the drive circuit (18) and serving to shape a waveform of the drive signal. The drive circuit (18) comprises a pulse generator (100) which generates pulses; a converter circuit (102) which receives the pulses and produces charge packets at a rate which equals a desired drive frequency; and, the piezoelectric actuator (14). The piezoelectric actuator (14) receives the charge packets and, by its capacitive nature, integrates the charge packets to shape the waveform of the drive signal. Preferably, the piezoelectric actuator (14) integrates the charge packets to yield a drive field that approximates a sine wave. In one non-limiting example embodiment, the pulse generator (100) comprises a microcontroller-based pulsed width modulator (PWM) circuit (116) and the converter circuit (102) comprises a flyback circuit.

Abstract: A drive circuit (18) senses a parameter of a piezoelectric actuator (14) operating in a device (10) and adjusts a drive signal of the piezoelectric actuator in accordance with the parameter. The drive circuit comprises a controller (100) which controls a drive signal applied to the piezoelectric actuator (14); a feedback monitor (122) which obtains a feedback signal from the piezoelectric actuator while the piezoelectric actuator works; and, a processor (116) which uses the feedback signal to determine the parameter of the piezoelectric actuator. In one example mode, the parameter of the piezoelectric actuator which is determined by the piezoelectric actuator drive circuit is the capacitance or dielectric constant of the piezoelectric actuator. In other example modes, the parameter of the piezoelectric actuator which is determined by the piezoelectric actuator drive circuit is impedance or resonant frequency of the piezoelectric actuator.