Abstract: A pressure sensor is constructed to include a sensor housing formed of metal, and a connector housing mainly formed of synthetic resin. The connector housing includes a shoulder portion thereof in the form of a metal plate having an inner and an outer periphery thereof. On the shoulder portion, there is formed a juncture of the sensor and connector housing as a result of joining the sensor and connector housing by curling a projecting portion or one of two end portions of the sensor housing toward the shoulder portion. Wherein, the curling is performed under engagement of the sensor and connector housing therebetween, for assembling the pressure sensor.

Abstract: A flow control valve includes a valve body having a substantially cylindrical bore, and a substantially cylindrical valve element received within the cylindrical bore of the valve body to be reciprocatable. The valve body and the valve element define first and second chambers separated by the valve element. The valve body has a circumferential groove surrounding the valve element, and a plurality of radially-extending passage holes communicating with the circumferential groove. The circumferential groove and the passage holes form portions of the second chamber. The valve element has a plurality of radially-extending throttle holes for establishing communication between the circumferential groove and the first chamber. The flow rate of operation oil flowing between the first chamber and the second chamber via the throttle holes is changed through axial movement of the valve element.

Abstract: A pressure detection device for detecting an increase of pressure acting thereon includes an electrically conductive device housing which has an accommodation bore extending inward from one end of the device housing and a slide bare extending between the accommodation bore and the other end of the device housing. A piston is slidably disposed within the slide bore and adopted to receive a pressure, and a terminal serving as one electric contact is fixed to the accommodation bore via an electrical insulator. A disk spring serving as the other electric contact deforms due to a pressing force of the piston and coming in contact with the terminal. The pressure detection device further comprises an electro-functional member attached to either the terminal or the disk spring in which the electro-functional member is changeable its electric resistance due to an impressed pressing force acting thereon.

Abstract: A pressure switch includes a switch housing which has an accommodation bore extending inward from one end of the switch housing, and a slide bore extending between the accommodation bore and the other end of the switch housing. A piston is slidably disposed within the slide bore and is adapted to receive a pressure. A terminal serving as one electric contact is fixed to the accommodation bore via a holding ring made of an insulating material. A disk spring serving as the other electric contact is disposed between the piston and the terminal. The disk spring deforms due to a pressing force of the piston and comes in contact with the terminal. The pressure switch further comprises an annular elastic ring placed on the outer end of the holding ring. An end portion of the switch housing is deformed inward so as to elastically deform the elastic ring, thereby sealing the opening portion of the accommodation bore.

Abstract: A variable-displacement vane-pump has a rotor which is rotatably supported by a pump housing in coaxial relationship therewith, and a cam ring interposed between the rotor and the pump housing in eccentric relationship with the pump housing. The rotor has radially outwardly slidable vanes on its outer peripheral surface in contact with an inner surface of the cam ring. Two side plates are disposed on both sides of the vanes, thereby defining pump chambers between every adjacent vanes. An arc-shaped intake port and an arc-shaped exhaust port are formed in one of two side plates, and respectively open into the pump chambers along one side face of the cam ring. In the other side face of the cam ring, a groove is formed except for the region corresponding to the exhaust port, and a partially cut off annular friction ring is disposed within the groove while urged by a seal ring into close contact with the other side plate.

Abstract: A flow volume control device for a power assisted steering device having a main control valve device, whose main valve spool is movable to establish the communication of an inlet passage with a bypass passage when the flow rate of pressurized fluid supplied from an engine-driven pump to the steering device through the inlet passage and first and second throttle passages disposed in parallel relation exceeds a predetermined value. For safe driving at a high speed, an auxiliary control valve device is further provided, whose auxiliary valve spool is moved to close the second throttle passage when high-speed driving causes pressurized fluid from the pump to increase in volume, to thereby bring about a predetermined pressure drop across said inlet passage.