Abstract: A charger includes a battery pack receiving therein a plurality of batteries and having a projection provided with a contacting terminal, and a charger section having a mounting hole provided with a charging terminal, the battery pack being set on the charger section with the projection mounted into the mounting hole of the charger section for charging the batteries. The battery pack has vent ports through a wall on the side having the projection, while the charger section has blast ports at positions opposing the vent ports and a blower disposed to be on a side of the mounting hole and below the blast ports, for blowing air from the blower, through the vent ports into the interior of the battery pack, for elevating blow rate to the battery pack, battery cooling and gas discharge out of the battery pack.

Abstract: A matrix relay is formed with a plurality of latching relays arranged in a matrix and mounted on a base of an electrically insulative material. Each of the latching relays comprises an excitation coil, permanent magnet, a pair of first and second fixed contacts, and an armature carrying a pair of first and second movable springs each providing movable contacts. The armature is magnetically coupled to the excitation coil so as to be movable in response to energization of the coil by current of selective polarity between close and open positions of the fixed and movable contacts. A plurality of the armatures of the latching relays arranged in a row of the matrix are assembled into a single armature block to be mounted on the base as a single unit. The armature block comprises a single pair of first and second supporting members made of an electrically conductive material.

Abstract: An infrared detector is arranged so that a detection-input processing circuit part including an infrared sensor mounted on a circuit board is housed as isolated from ambient air in a chamber inhibiting any ambient air inflow, for sensing infrared rays emitted from a human body or the like object as condensed by a condenser irrespective of the ambient air conditions, the sensing ability of the infrared sensor the accuracy of which is likely to be easily deteriorated even with a very small change in the ambient temperature can be thereby stabilized, and a highly accurate infrared detection can be constantly achieved.