The University of Tokyo

Saginomiya Seisakusho, Inc.

Shizuoka University

Kabushiki Kaisha Saginomiya Seisakusho

Omron Corporation

Keio University

Central Research Institute of Electric Power Industry

Saginomiva Seisakusho, Inc.

Hiroyuki Mitsuya

Hiroshi Toshiyoshi

Hiroyuki Fujita

Hisayuki Ashizawa

Gen Hashiguchi

Kazunori Ishibashi

Hiroaki Honma

Hiroshi Imamoto

Masato Suzuki

Takeaki Yajima

Takuro Ishikawa

Masatoshi Oba

Tatsuhiko Sugiyama

Shimpei Ono

Akito Mori

Yukiya Tohyama

Song-Ju Kim

Masashi Aono

A measurement system includes a vibration generation unit that generates sound or vibration in response to a change in environmental state quantity, a vibration-driven energy harvesting unit that generates electric power using the sound or vibration generated by the vibration generation unit, and a transmission unit that is driven with the electric power generated by the vibration-driven energy harvesting unit and transmits predetermined information.

Measurement system and diagnosis system

An electrostatic device includes: a fixed portion, a moveable portion, and an elastically-supporting portion that are formed in a same substrate; and a first glass package and a second glass package that are anodically bonded to each other on one and the other of front and back surfaces of the substrate with the fixed portion and the elastically-supporting portion separated from each other, the second glass package forms a sealed space in which the moveable portion is arranged between the first and second glass packages, an electret is formed at least partially in the fixed portion and the moveable portion, and a first electrode connected to the fixed portion and exposed on an outer surface of the second glass package and a second electrode connected to the elastically-supporting portion and exposed on the outer surface of the second glass package are formed in the second glass package.

Electrostatic device, electrostatic device intermediate body and production method

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.

Vibration-driven energy harvesting device

An energy harvesting device having an energy converting element that converts environmental energy into electric energy, an environmental sensor that is disposed in an identical environment as the energy converting element, and a power supply circuit that receives electricity from the energy converting element and outputs the electricity to an external load. The power supply circuit is configured to change an operation condition of, for example, a voltage converting circuit of the power supply circuit, in accordance with an output of the environmental sensor.

Environmental energy harvesting device

A vibration-driven energy harvesting element includes: a pair of fixed electrode portions that have a plurality of fixed comb teeth and are arranged such that the plurality of fixed comb teeth face each other; and a movable electrode portion that is arranged between the pair of fixed electrode portions and has a pair of a plurality of movable comb teeth being inserted between the fixed comb teeth of the respective fixed electrode portions, wherein: the vibration-driven energy harvesting element has a three-terminal structure in which the fixed comb teeth and/or the movable comb teeth are electretized; a gap dimension of a clearance region between the fixed comb teeth and the movable comb teeth is smaller than 20 &#x3bc;m; and an aspect ratio being a ratio of a dimension of the clearance region in a comb tooth height direction to the gap dimension of the clearance region, is 20 or more.

Vibration-driven energy harvesting element

A vibrational energy harvester element includes: a first electrode; a second electrode that moves in a predetermined direction with respect to the first electrode; a third electrode; a fourth electrode that moves in the predetermined direction with respect to the third electrode; and a support portion that supports the second electrode and the fourth electrode so that they are movable along the predetermined direction; and wherein: the first electrode and the third electrode are disposed along the predetermined direction; at least one of facing surfaces of the first electrode and the second electrode, and at least one of facing surfaces of the third electrode and the fourth electrode, are electrically charged; and the support portion supports the second electrode and the fourth electrode in a state in which electrostatic force between the first electrode and the second electrode, and electrostatic force between the third electrode and the fourth electrode are balanced along the predetermined direction.

Vibrational energy harvester element

The present invention enables frequency response in a wide band without lowering the Q value. This vibrational energy harvester device is provided with: a movable part capable of vibration in a vibration direction as a result of mechanical vibrational energy applied from the exterior, said movable part being provided with a first surface along the vibration direction; and a fixed part provided with a second surface facing the first surface of the movable part with an interval therebetween, said fixed part being configured so as to be positionally fixed even against vibrational energy. A plurality of projections protruding in a direction orthogonal to the vibration direction are formed so as to be arranged like comb teeth in the vibration direction on each of the first surface of the movable part and the second surface of the fixed part. An electret film is formed on at least the first surface of the fixed part or on at least the second surface of the movable part. The vibrational energy harvester device is configured so that the spring rate of the movable part is modulated as a function of the position of the vibration direction by electrostatic force acting between the movable part and the fixed part.

Vibrational energy harvester device

Provided is an electrostatic-type vibrational energy harvester device that makes it possible to efficiently rectify and charge power from low acceleration to high acceleration of vibrational energy applied from the exterior. The vibrational energy harvester device is provided with: a movable part capable of vibrating in a vibration direction as a result of mechanical vibrational energy, said movable part being provided with a first surface along the vibration direction; and a fixed part provided with a second surface facing the first surface of the movable part with a gap therebetween so that it is possible for the movable part to vibrate in the vibration direction. A plurality of recessed portions and protruding sections are formed in an alternating manner in the vibration direction on the surfaces of each of the first surface of the movable part and the second surface of the fixed part. An electret film is formed on at least one of the fixed part and the movable part. The vibrational energy harvester device is configured so that a force factor (electromechanical conversion factor) having a value that corresponds to the gap between the first surface of the movable part and the second surface of the fixed part becomes small when the vibration amplitude of the movable part is small and large when the vibration amplitude of the movable part is large.

A vibration energy harvester includes: a first electrode; and a second electrode that can be displaced relative to the first electrode along a predetermined vibrating direction. At least either of a surface of the first electrode and a surface of the second electrode facing opposite each other is electrically charged. Power is generated as the second electrode becomes displaced causing a change in electrostatic capacitance between the first electrode and the second electrode. A range having included therein at least a vibrational center of the second electrode, over which the electrostatic capacitance remains unchanged even as the second electrode is displaced, is set.

Vibration energy harvester

An electret element includes: an Si layer, an SiOlayer formed at a surface of the Si layer; and an electret formed at the SiOlayer near an interface of the SiOlayer and the Si layer.

Electret element, electromechanical converter and method for manufacturing electret element

A vibration-driven energy harvester includes: a fixed electrode; a movable electrode that is disposed so as to face opposite the fixed electrode and is allowed to move relative to the fixed electrode; and an ionic liquid disposed between the fixed electrode and the movable electrode which face opposite each other, wherein: power is generated as an external vibration moves the movable electrode, causing a change in at least one of an area of an electrical double layer formed on two sides of an interface of the fixed electrode and the ionic liquid and an area of an electrical double layer formed on two sides of an interface of the movable electrode and the ionic liquid.

Vibration-driven energy harvester

An actuator includes: an electrostatic actuation mechanism including a stationary electrode and a movable electrode; a first movable part driven by the electrostatic actuation mechanism; a first elastic support part that elastically supports the first movable part; an electret formed in at least one of the stationary electrode and the movable electrode; and a drive control unit that controls application of voltage to the electrostatic actuation mechanism. In the actuator a plurality of stable states are set in which the first movable part is positioned at a stable position at which an electrostatic force generated by the electret matches with an elastic force exerted by the first elastic support part or at a stable position near such stable position. By applying a voltage to the electrostatic actuation mechanism, the first movable part may be displaced from any stable position to another stable position.

Actuator, shutter device, fluid control device, switch, and two-dimensional scanning sensor device

A vibration energy harvester includes: a pair of electrodes provided so as to face opposite each other, with at least one of the pair of electrodes allowed to move; and an ion gel provided between the pair of electrodes, which is formed by using an ionic liquid, wherein: as an external vibration causes the electrode to move along a direction in which a distance between the pair of electrodes changes, power is generated through a change in an area of an electric double layer formed on two sides of an interface of each electrode and the ion gel.

A pressure sensor includes: a fixed part; a ring-like oscillator that is supported on the fixed part by a plurality of support beams; a plurality of electrodes that are provided on the fixed part and arranged in an oscillating direction of the ring-like oscillator with a gap; electret films that are formed on either one of opposite surfaces of the ring-like oscillator and the electrodes.

Pressure sensor and pressure detection device

A device member including a cavity, includes a base member, an interlayer, an upper layer, an opening portion, and a gas-permeable sealing layer. The base member includes a first semiconductor. The interlayer is formed on the base member and is non-conductive. The upper layer is formed on the interlayer and includes a second semiconductor. The opening portion is formed at the upper layer. The gas-permeable sealing layer is formed to seal the opening portion formed at the upper layer. The cavity is formed by removing the interlayer with an etching gas that penetrates through the sealing layer.

Growing community of inventors

Sayama, Japan

Hiroyuki Mitsuya