Abstract: A fuel cell system that raises temperature of fuel cells by supplying heated air to the fuel cells during starting up period. The fuel cell system includes a plurality of fuel cells, a fuel supply path connected parallelly to the fuel cells to provide fuel thereto, an air supply path connected serially to the fuel cells to provide air thereto, a heat exchanger arranged in the fuel supply path to heat air or fuel, an air heat exchanger arranged in the air supply path to heat air; and a connection path connecting a position of the air supply path upstream to the air heat exchanger with a position of the fuel supply path upstream to the heat exchanger. A first control valve is arranged in the air supply path for controlling the air flowing into to the air heat exchanger. A second control valve arranged in the connection path for controlling the air flowing into the heat exchanger.

Abstract: A fuel cell system that raises temperature of fuel cells by supplying heated air to the fuel cells during starting up period. The fuel cell system includes a plurality of fuel cells, a fuel supply path connected parallelly to the fuel cells to provide fuel thereto, an air supply path connected serially to the fuel cells to provide air thereto, a heat exchanger arranged in the fuel supply path to heat air or fuel, an air heat exchanger arranged in the air supply path to heat air; and a connection path connecting a position of the air supply path upstream to the air heat exchanger with a position of the fuel supply path upstream to the heat exchanger. A first control valve is arranged in the air supply path for controlling the air flowing into to the air heat exchanger. A second control valve arranged in the connection path for controlling the air flowing into the heat exchanger.

Abstract: Provided is an actuator for a variable compression ratio mechanism of an internal combustion engine, which improves productivity.

Abstract: Provided are an actuator for a link mechanism for an internal combustion engine and a wave gear speed reducer, which improve both input efficiency and driving efficiency. According to the invention, the wave gear speed reducer is configured so that a flexible external gear is bent into an elliptical shape using a wave generating device rotated by an input shaft to partially engage external teeth of the flexible external gear with internal teeth of an internal gear portion, and further configured so that an engaging part between the flexible external gear and the internal gear portion is rotated. The external teeth are larger in curvature than the internal teeth in a contact portion between the internal and external teeth.

Abstract: A strain wave gearing apparatus includes a rigid internal gear including a plurality of teeth on an inner periphery thereof, a cylindrical flexible external gear including a plurality of teeth on an outer periphery thereof, and a wave generator having an elliptic outer periphery. A contact of the outer periphery of the wave generator with an inner periphery of the external gear causes the external gear to be elliptically distorted and meshed with the internal gear at a part of the teeth of the external gear in a direction of a major axis. A rotation of the wave generator causes a position of the mesh to be moved in a circumferential direction. The elliptic outer periphery of the wave generator includes a major axis in common with a reference ellipse, and is different from the reference ellipse in terms of a shape of at least a part thereof in the circumferential direction.

Abstract: Provided is a strain wave gear speed reducer which can improve both load torque performance and productivity, a method for manufacturing a strain wave gear speed reducer, and an actuator for link mechanism for internal combustion engine.