Abstract: A viscous fluid coupling device includes a drive shaft, a housing rotatably supported by the drive shaft, a partition wall dividing an interior space of the housing into an operation chamber and a storage chamber having a circular arc portion, a rotor accommodated in the operation chamber and fixed to the drive shaft, a supply passage for supplying operating fluid from the storage chamber to the operation chamber, a return passage for returning the operating fluid in the operation chamber to the storage chamber, and a first valve disposed in the supply passage and the return passage respectively. The first valve is closed when the drive shaft rotates at a speed lower than a predetermined rotation speed and opened when the drive shaft rotates at the predetermined rotation speed. The viscous coupling device further includes an opening of the supply passage and a second valve for opening and closing the opening.

Abstract: An externally-controlled fluid coupling includes a driving disk fixed to a driving rotational shaft, a case member and a cover member rotatably supported by the rotational shaft, a separating plate for forming an operation chamber and a storage chamber between the case member and the cover member, a supply passage for supplying the fluid to the operation chamber, a return passage for returning the fluid to the storage chamber, a supply/return valve for opening or closing the supply/return passage and an electromagnetic actuating apparatus including an electromagnet for actuating the supply/return valves. The electromagnet generates a first power of magnetism for actuating the supply valve and a second power of magnetism for actuating the return valve. The values of the first and second powers of magnetism are different from each other so that the supply valve and the return valve open/close nonsynchronously.

Abstract: A water pump is provided with pressure-feed means whereby coolant that has leaked into the space between a bearing and a seal member in a pump housing is forcibly fed into an radiator reservoir tank in order to be recovered.

Abstract: A water pump is provided with pressure-feed means whereby coolant that has leaked into a space between a bearing and a seal member in a pump housing is recovered by being forcibly fed into an radiator reservoir tank.

Abstract: A liquid pump in which a perfect seal is achieved between a liquid and the atmosphere without the use of magnets includes a pump shaft rotatably supported inside housings and having an impeller secured thereto for impelling a liquid through the pump, a driven unit provided inside the housing for rotating the pump shaft, a driving unit coupled to external power, and a resilient member provided between the driven unit and the driving unit for effecting sealing liquid-tightly between the driven unit and the driving unit on the side of the impeller and transmitting force from the driving unit to the driven unit.

Abstract: A viscous fluid coupling device comprises a housing; a partition board dividing an internal space in the housing into a storage chamber and an operation chamber, the partition board having first communicating holes to communicate the storage chamber with the operation chamber; a rotor which is provided in the operation chamber and is secured to one end portion of a drive shaft so as to rotate together with the drive shaft; a valve provided in the storage chamber to open and close the first communicating holes; and a rod having one end secured to the valve and the other end secured to the inner peripheral portion of a spiral bimetal. The rod is rotatably supported by the housing and the housing and the rotor have labyrinth grooves in the surfaces which are confronted with each other.

Abstract: A fluid coupling includes an input shaft, a housing having a space therein and supported by the input shaft via a bearing, a dividing plate dividing the space into a storing chamber and an acting chamber through holes made in the dividing plate, a valve opening and closing the through holes, a rotor fixed to the input shaft and located in the acting chamber, pumping holes made in the dividing plate, pumping projections on the dividing plate at the downstream side of the pumping holes, and a seal located between the pumping holes and the pumping projections.

Abstract: A viscous fluid coupling has a rotor including peripheral teeth with distal ends closely facing an inside surface of an output member. The distal ends of the teeth form flat surfaces parallel with the output member to form a rotary seal therewith, which reduces variations in the rotational speed of the output member.