Abstract: An actuator of a variable compression ratio mechanism which includes: a control link; a control shaft; a housing; a wave gear speed reduction device arranged to transmit the reduced rotation speed to the control shaft; a first bearing portion which is provided between the control shaft and a wave generation device of the wave gear speed reduction device, and which rotatably supports a first axial end portion of the wave generation device; and a second bearing portion which is provided between the housing and the wave generation device, and which rotatably supports an second axial end portion of the wave generation device, at least one of the first bearing portion and the second bearing portion being disposed inside an axial width of an outer circumference portion of the wave generation device.

Abstract: In a cylindrical valve body 3, a first opening portion M1 for a heater heat exchanger and a second opening portion M2 for an oil cooler are arranged parallel in an axial direction of the valve body 3. A third opening portion M3 for a radiator is arranged in a different circumferential direction position from the first or second opening portion M1 or M2 on an outer peripheral surface of the valve body 3 so that at least a part of the third opening portion M3 overlaps with the first or second opening portion M1 or M2 in the axial direction.

Abstract: An actuator of a variable compression ratio mechanism includes: a control link; an arm link; a control shaft; a housing including a receiving portion in which a connection portion between the second end portion of the control link and the arm link is received, and a support hole formed within the housing, and rotatably supporting the control shaft; and a speed reduction device, the control shaft including a fixing portion inserted and fixed within the receiving portion in a fixing hole formed in the arm link at a predetermined axial position, and a first journal portion which is formed at a tip end portion of the control shaft, which has a diameter smaller than a diameter of the fixing portion, and which is supported by a first bearing hole formed in the support hole.

Abstract: An actuator of a variable compression ratio mechanism which includes: a control link; a control shaft; a housing; a wave gear speed reduction device arranged to transmit the reduced rotation speed to the control shaft; a first bearing portion which is provided between the control shaft and a wave generation device of the wave gear speed reduction device, and which rotatably supports a first axial end portion of the wave generation device; and a second bearing portion which is provided between the housing and the wave generation device, and which rotatably supports an second axial end portion of the wave generation device, at least one of the first bearing portion and the second bearing portion being disposed inside an axial width of an outer circumference portion of the wave generation device.

Abstract: A water pump includes a pump shaft surrounded by a pump housing having a tubular section. A pulley having a cylindrical section and a flange wall is mounted on an end section of the pump shaft. An impeller is mounted on the other end section of the pump shaft. A mechanical seal is coaxially disposed between the tubular section and the pump shaft. A bearing is coaxially disposed between the tubular section of the pump housing and the cylindrical section of the pulley. In this water pump, the pump shaft includes a coaxial small diameter shaft section located at its first part which is located axially between the mechanical seal and the flange wall. The small diameter shaft section has a diameter smaller than a diameter of a second part of the pump shaft on which the mechanical seal is disposed so as to form an annular step portion.

Abstract: A centrifugal pump comprises a hollow pump body. An impeller is rotatably installed in a pump chamber defined in the pump body. The impeller has a front side facing a major part of the pump chamber and a rear side facing a bottom wall of the pump chamber. The hollow pump body has both a water discharge passage and a water discharge port formed therein. A water guide ridge is positioned between the pump chamber and the water discharge passage to smooth a water flow from the pump chamber toward the water discharge port. The water guide ridge extends upstream in the water discharge passage and projects from the inner wall toward the major part of the pump chamber. The water guide ridge has an upstream end portion sloped. With this sloped upstream end portion, undesired cavitation in the pump is suppressed or at least minimized.