A VCM is disclosed, the VCM including a rotor including a bobbin arranged at an upper surface of a base formed with an opening, and a driving coil wound on the bobbin, a stator including a driving magnet opposite to the driving coil, and a yoke secured by the driving magnet at an inner surface of a lateral plate, and a tilting unit including a tilt magnet arranged at an outer surface of the lateral plate, a housing fixing the tilt magnet, and a tilt coil unit opposite to the tilt magnet.

A vibration motor includes a stationary portion, a vibrating body, an elastic member, and a damper member. The elastic member includes a first extending portion, a second extending portion, a first connection portion, a second connection portion, a third extending portion, a fourth extending portion, a third connection portion, a fourth connection portion, and a fifth connection portion. The damper member includes a first longitudinal portion and a second longitudinal portion. An inner section including the first extending portion, the third extending portion, and the fifth connection portion directly opposes an upper surface of a weight in plan view in an up-down direction.

Provided is a vibration-driven energy harvesting device that can enhance the power generation efficiency of the vibration-driven energy harvesting device even in a case where vibration is changed. The vibration-driven energy harvesting device includes a vibration-driven energy harvesting element that generates power in accordance with vibration of an electrode; an output unit that supplies the power generated by the vibration-driven energy harvesting element to a load resistor once being connected to the load resistor; and an adjustment unit that adjusts an input impedance of the output unit in accordance with a signal corresponding to an acceleration in the vibration.

A vibration-driven energy harvesting device includes a vibration-driven energy harvesting element that generates power according to vibrations of an electrode; an output unit that, when connected to a load resistor, extracts power generated by the vibration-driven energy harvesting element; a judgment unit that judges whether or not a power value of the power is greater than a predetermined threshold value; a determination unit that determines an input impedance of the output unit based on a judgment result obtained by the judgment unit; and an adjustment unit that adjusts the input impedance of the output unit according to a determination made by the determination unit.

Disclosed is an electromechanical generator for converting mechanical vibrational energy into electrical energy, the electromechanical generator comprising: a mass resiliently connected to a body by a biasing device and adapted to oscillate about an equilibrium point relative to the body with an oscillation amplitude, a transducer configured to convert oscillations of the mass about the equilibrium point relative to the body into electrical energy, and a resilient device disposed between the biasing device and one of the mass and the body, wherein the resilient device is configured to be deformed between the biasing device and the one of the mass and the body only when the oscillation amplitude exceeds a predetermined non-zero threshold amplitude. The resilient device may comprise one of a helical spring, an O-ring and a spring washer, such as a Belleville washer, a curved disc spring, a wave washer, and a split washer.

Disclosed is an electromechanical generator for converting mechanical vibrational energy into electrical energy, the electromechanical generator comprising: a mass resiliently connected to a body by a biasing device and adapted to oscillate about an equilibrium point relative to the body with an oscillation amplitude, a transducer configured to convert oscillations of the mass about the equilibrium point relative to the body into electrical energy, and a resilient device disposed between the biasing device and one of the mass and the body, wherein the resilient device is configured to be deformed between the biasing device and the one of the mass and the body only when the oscillation amplitude exceeds a predetermined non-zero threshold amplitude. The resilient device may comprise one of a helical spring, an O-ring and a spring washer, such as a Belleville washer, a curved disc spring, a wave washer, and a split washer.

Disclosed is an electromechanical generator for converting mechanical vibrational energy into electrical energy, the electromechanical generator comprising: a mass resiliently connected to a body by a biasing device and adapted to oscillate about an equilibrium point relative to the body with an oscillation amplitude, a transducer configured to convert oscillations of the mass about the equilibrium point relative to the body into electrical energy, and a resilient device disposed between the biasing device and one of the mass and the body, wherein the resilient device is configured to be deformed between the biasing device and the one of the mass and the body only when the oscillation amplitude exceeds a predetermined non-zero threshold amplitude. The resilient device may comprise one of a helical spring, an O-ring and a spring washer, such as a Belleville washer, a curved disc spring, a wave washer, and a split washer.

Disclosed is an electromechanical generator for converting mechanical vibrational energy into electrical energy, the electromechanical generator comprising: a mass resiliently connected to a body by a biasing device and adapted to oscillate about an equilibrium point relative to the body with an oscillation amplitude, a transducer configured to convert oscillations of the mass about the equilibrium point relative to the body into electrical energy, and a resilient device disposed between the biasing device and one of the mass and the body, wherein the resilient device is configured to be deformed between the biasing device and the one of the mass and the body only when the oscillation amplitude exceeds a predetermined non-zero threshold amplitude. The resilient device may comprise one of a helical spring, an O-ring and a spring washer, such as a Belleville washer, a curved disc spring, a wave washer, and a split washer.

A power generation system in an embodiment includes a power generator, a rectifying and smoothing circuit, a converter, a voltage measurement unit, and a switch. The power generator outputs AC power. The rectifying and smoothing circuit converts the AC power to DC power and smooths the DC power. The voltage measurement unit measures an average voltage of the AC power or a voltage of the smoothed DC power. The converter transforms the smoothed DC power. The switch is disposed between the rectifying and smoothing circuit and the converter, and becomes an ON state when the measured voltage becomes a reference voltage or higher.

A power generation system in an embodiment includes a power generator, a rectifying and smoothing circuit, a converter, a voltage measurement unit, and a switch. The power generator outputs AC power. The rectifying and smoothing circuit converts the AC power to DC power and smooths the DC power. The voltage measurement unit measures an average voltage of the AC power or a voltage of the smoothed DC power. The converter transforms the smoothed DC power. The switch is disposed between the rectifying and smoothing circuit and the converter, and becomes an ON state when the measured voltage becomes a reference voltage or higher.