Abstract: A polarizing plate may have high transmittance characteristics and suppressed reflected light. An optical device may be provided with the polarizing plate. The polarizing plate may have a wire grid structure that includes a transparent substrate and grid-like projection portions arranged on the transparent substrate at a pitch shorter than the wavelength of light in a used bandwidth and extending in a predetermined direction. The grid-like projection portions may each have a reflective layer and a dielectric layer in order from the transparent substrate side. When viewed from the predetermined direction, the reflective layer has may have a step on the side thereof and may have the largest bottom width on the transparent substrate side.

Abstract: Provided is a structural birefringence-type inorganic wave plate having excellent heat resistance and durability, and a fine pattern. Also provided is a manufacturing method for an inorganic wave plate by which, even in the case of a fine pattern, productivity is high, and a desired phase difference is easily achieved and stably obtained. This inorganic wave plate is obtained by utilizing a selective interaction between a polymer having a repeating unit containing a carbonyl group, and a metallic oxide precursor, the inorganic wave plate having a wire grid structure provided with a transparent substrate, and grid-shaped protruding portions arranged at a pitch shorter than the wavelength of light in a used band on at least one surface of the transparent substrate and extending in a predetermined direction, the main component of the grid-shaped protruding portion being a metallic oxide.

Abstract: A switch device capable of safely opening an electrical circuit in response to an abnormality such as wetting with water or liquid leaking from a battery. The device includes a first conductor connected to an external circuit and having a relatively high ionization tendency, and a second conductor arranged close to the first conductor and having a relatively low ionization tendency which is lower than that of the first conductor, a reaction part which electrically corrodes the first conductor is formed by a liquid between the first and second conductors.

Abstract: A switch device capable of safely opening or short-circuiting an electrical circuit in response to an abnormality such as wetting with water or liquid leaking from a battery is provided. The device includes a conductor connected to an external circuit, and a reaction part including a liquid-soluble material which opens the conductor and the external circuit and which dissolves on contacting a liquid entering the device interior to electrically connect the conductor and the external circuit.

Abstract: A fuse element comprises a low melting point metal layer, a first high melting point metal layer having a higher melting point than a melting point of the low melting point metal layer, and a restricting portion including a high melting point material having a higher melting point than a melting point of the low melting point metal layer and configured to restrict flow of the low melting point metal or deformation of a layered body constituted by the first high melting point metal layer and the low melting point metal layer.

Abstract: A switch device capable of safely opening or short-circuiting an electrical circuit in response to an abnormality such as wetting with water or liquid leaking from a battery is provided. The device includes first and second conductors connected to an external circuit, and a reaction part including an insulating material which changes state on contact with a liquid, the first and second conductors being electrically connected or disconnected by the insulating material changing state on contact with the liquid.

Abstract: A fuse element comprises a low melting point metal layer, a first high melting point metal layer having a higher melting point than a melting point of the low melting point metal layer, and a restricting portion including a high melting point material having a higher melting point than a melting point of the low melting point metal layer and configured to restrict flow of the low melting point metal or deformation of a layered body constituted by the first high melting point metal layer and the low melting point metal layer.

Abstract: A switch device capable of safely opening or short-circuiting an electrical circuit in response to an abnormality such as wetting with water or liquid leaking from a battery is provided. The device includes a conductor connected to an external circuit, and a reaction part including a liquid-soluble material which opens the conductor and the external circuit and which dissolves on contacting a liquid entering the device interior to electrically connect the conductor and the external circuit.

Abstract: A switch device capable of safely opening an electrical circuit in response to an abnormality such as wetting with water or liquid leaking from a battery. The device includes a first conductor connected to an external circuit and having a relatively high ionization tendency, and a second conductor arranged close to the first conductor and having a relatively low ionization tendency which is lower than that of the first conductor, a reaction part which electrically corrodes the first conductor is formed by a liquid between the first and second conductors.

Abstract: A switch device capable of safely opening or short-circuiting an electrical circuit in response to an abnormality such as wetting with water or liquid leaking from a battery is provided. The device includes first and second conductors connected to an external circuit, and a reaction part including an insulating material which changes state on contact with a liquid, the first and second conductors being electrically connected or disconnected by the insulating material changing state on contact with the liquid.

Abstract: An electronic power supply device supplies electric power from a plurality of battery cells to an electronic power equipment and has an inner case for housing the plurality of battery cells and an outer case for housing the inner case. The electronic power supply device is designed to protect the plurality of battery cells from water damage and from an impact in the event that the electronic power supply device is accidentally dropped.

Abstract: A battery pack in one aspect of the present disclosure comprises: a plurality of battery blocks, a plurality of conduction/interruption units, and a control unit. The control unit selects one battery block to be electrically connected to an external device from among the plurality of battery blocks, on the basis of detection results obtained from a state detection unit, and sets the conduction/interruption unit corresponding to the selected battery block to a conducting state.

Abstract: A battery pack in one aspect of the present disclosure comprises: a plurality of battery blocks, a plurality of conduction/interruption units, and a control unit. The control unit selects one battery block to be electrically connected to an external device from among the plurality of battery blocks, on the basis of detection results obtained from a state detection unit, and sets the conduction/interruption unit corresponding to the selected battery block to a conducting state.

Abstract: An electronic power supply device supplies electric power from a plurality of battery cells to an electronic power equipment and has an inner case for housing the plurality of battery cells and an outer case for housing the inner case. The electronic power supply device is designed to protect the plurality of battery cells from water damage and from an impact in the event that the electronic power supply device is accidentally dropped.

Abstract: A power supply device includes battery interfaces configured to removably receive at least three batteries and a connection circuit configured to electrically connect the at least three batteries to each other. The connection circuit is capable of connecting at least two batteries in parallel and connecting at least one other battery to the at least two parallel-connected batteries in series. According to this power supply device, it is possible to supply high power to an electric device by connecting the batteries in series. In addition, it is possible to supply almost all of the electric power stored in the batteries to the electric device, even if amount of the remaining electric power in each battery is substantially uneven.

Abstract: Cooling air intake port (52), cooling air exhaust port (55), and securing walls (86, 87), which contact and secure the side surfaces of one or more battery cells (72), may be defined within two battery pack housing halves (50, 80). When battery pack (99) is assembled, at least one cooling air passage (91, 92) is defined by the side surfaces of the battery cells, the interior surface of the battery pack housing, and the securing walls. The cooling air passage connects the cooling air intake port to the cooling air exhaust port. By forcing cooling air through the cooling air passage, the battery cells can be effectively and efficiently cooled.

Abstract: A battery pack usable as a power source of an electric device, is disclosed, in which battery modules are in series; each battery module is configured to include battery cells in series; a discharge controller controls discharge power which is supplied from the battery modules to the electric device; a modulator modulates a voltage of each module between a high voltage and a low voltage which is higher than zero and lower than the high voltage; the high voltage and the low voltage are set to allow a load device of the electric device to operate by the high voltage, and to allow the load device not to operate by the low voltage; and the discharge controller operates by the battery modules, irrespective of whether each module outputs the high voltage or the low voltage.

Abstract: A cordless power tool system is provided which is driven by using a battery pack as a power source, and which has work performance equivalent to an AC power tool is driven by using a commercial power source as a power source. The cordless power tool system is configured to include: a battery pack in which DC voltage of battery modules is converted into AC voltage, to thereby output the AC voltage having a level which is comparable to that of the commercial power source; a cordless power tool which is driven by using the battery pack as a power source; an electrical cord adapter which allows power supply from the commercial power source to the battery pack for charging the battery pack; and an electrical cord adapter which allows power supply from the commercial power source to the cordless power tool for driving the cordless power tool.

Abstract: Cooling air intake port (52), cooling air exhaust port (55), and securing walls (86, 87), which contact and secure the side surfaces of one or more battery cells (72), may be defined within two battery pack housing halves (50, 80). When battery pack (99) is assembled, at least one cooling air passage (91, 92) is defined by the side surfaces of the battery cells, the interior surface of the battery pack housing, and the securing walls. The cooling air passage connects the cooling air intake port to the cooling air exhaust port. By forcing cooling air through the cooling air passage, the battery cells can be effectively and efficiently cooled.

Abstract: A battery system is disclosed which includes: a battery assembly; an AC-voltage generator for generating alternate current (AC) voltage from direct current (DC) voltage of the battery assembly; a battery charger for charging the battery assembly; and a detector for detecting application of AC voltage from the AC-voltage generator to the battery charger.