A piezoelectric element driving circuit includes a boosting circuit, a driving circuit, a waveform shaping circuit, and a computing circuit. The driving circuit includes a differential amplifier circuit with an LPF, an amplifier circuit with a BPF, an inverter, a resistor, and a comparator. The driving circuit applies a driving signal to a piezoelectric element of a piezoelectric pump. The waveform shaping circuit extracts a voltage signal from the driving circuit. On the basis of the voltage signal, the waveform shaping circuit and the computing circuit determine a voltage value corresponding to driving current flowing through the piezoelectric element. The computing circuit outputs a control signal to the boosting circuit on the basis of the voltage value. The boosting circuit sets the value of a DC supply voltage on the basis of the control signal, and outputs the DC supply voltage.

A pump device includes a first piezoelectric pump, a second piezoelectric pump connected in series to the first piezoelectric pump on an upstream side of the first piezoelectric pump, a driver unit that supplies alternating-current input power to the first piezoelectric pump and the second piezoelectric pump, and a distribution setting unit that sets a distribution ratio of the input power to be supplied from the driver unit to each of the first piezoelectric pump and the second piezoelectric pump, wherein the distribution setting unit sets a ratio of the input power for the second piezoelectric pump to the input power for the first piezoelectric pump to a value greater than 1 and equal to or less than 1.57.

A low hysteresis piezo-electric pump using a piezo-electric element as an actuator to dispense a liquid may maintain accurate viscous liquid discharge characteristics by adjusting an applied voltage in response to changes in behavioral characteristics of a piezo-electric actuator depending on causes such as temperature change.

A piezoelectric element driving circuit includes a boosting circuit, a driving circuit, a waveform shaping circuit, and a computing circuit. The driving circuit includes a differential amplifier circuit with an LPF, an amplifier circuit with a BPF, an inverter, a resistor, and a comparator. The driving circuit applies a driving signal to a piezoelectric element of a piezoelectric pump. The waveform shaping circuit extracts a voltage signal from the driving circuit. On the basis of the voltage signal, the waveform shaping circuit and the computing circuit determine a voltage value corresponding to driving current flowing through the piezoelectric element. The computing circuit outputs a control signal to the boosting circuit on the basis of the voltage value. The boosting circuit sets the value of a DC supply voltage on the basis of the control signal, and outputs the DC supply voltage.

A case for an electronic cigarette vaporiser, the case including an automatic lifting mechanism that lifts the vaporiser up a few mm from the case to enable a user to easily grasp the vaporiser and withdraw it from the case. The lifting mechanism can be spring- based. The case both re-fills the vaporiser with liquid and also re-charges a battery in the vaporiser.

A fluid control device includes a piezoelectric pump, an inhaler, and a valve. The piezoelectric pump has a gas suction hole and a gas discharge hole. The inhaler has a container, an inhalation port, and a connection hole. The valve has a first ventilation hole, a second ventilation hole, a third ventilation hole, a first valve housing, a second valve housing, and a valve body. The first ventilation hole of the valve is connected to the connection hole of the inhaler. The second ventilation hole of the valve is connected to the suction hole of the piezoelectric pump. The third ventilation hole of the valve is opened to the atmosphere. The valve body is held between the first valve housing and the second valve housing, and configures a first region and a second region.

A linear compressor employing a piezoelectric actuator operating in resonance at a frequency substantially below its natural resonant frequency, which is usually of the order of 10 kHz. Low frequency resonance operation of the actuator, of the order of 100 Hz., is achieved by incorporating the actuator and its housing with the moving compression piston, such that the moving mass is substantially increased, and by reduction of the effective piezoelectric stiffness using hydraulic amplification of the actuator displacement. Both these procedures result in a reduction of the actuator resonant frequency. The hydraulic amplification is achieved by using a hydraulic chamber with different sized pistons, linking the actuator motion with motion of the actuator housing, to which the compressor piston is attached. The high efficiency achieved and the lack of moving parts or the need for lubricating oil makes the compressor ideal for use in high reliability and high purity applications.

An aircraft assembly having: a first part; a second part, the second part being movably mounted with respect to the first part; an electro-hydraulic actuator coupled between the second part and a first anchor point, the actuator comprising a cylinder defining a bore and a piston and rod assembly slidably mounted within the bore and an active chamber within which an increase in fluid pressure causes the actuator to change during a first phase between first and second extension states to move the second part relative to the first part. The electro-hydraulic actuator further includes a hydraulic fluid supply circuit comprising a piezo-electric pump operable to supply pressurised fluid to the active chamber to change the actuator between first and second extension states.

A fluid device with a fluid chamber, the fluid device including a fluid chamber which is designed for receiving a fluid and which is commonly delimited by a device housing and a bending-elastic membrane element. The membrane element is fixed with a peripheral edge region to the device housing, wherein a membrane working section of the membrane element which is framed by the peripheral edge region can be deflected by a piezoactuator whilst carrying out a stroke movement, in order to change the volume of the fluid chamber. The membrane element is a functional constituent of the piezoactuator by way of it directly forming an electrically conductive electrode of the electrode arrangement of the piezoactuator.

A piezoelectric cooling chamber and method for providing the cooling system are described. The cooling chamber includes a piezoelectric cooling element, an array of orifices and a valve. A vibrational motion of the piezoelectric cooling element causes an increase or decrease in a chamber volume as the piezoelectric cooling element is deformed. The array of orifices is distributed on at least one surface of the chamber. The orifices allow escape of fluid from within the chamber during the decrease in the chamber volume in response to the vibration of the piezoelectric element. The valve is configured to admit fluid into the chamber when the chamber volume increases and to substantially prevent fluid from exiting the chamber through the valve when the chamber volume decreases.