Diesel Kiki Co., Ltd.

Zexel Gmbh

Koji Ichihashi

Kyoji Tanaka

Toshihiro Murayama

Jun-ichi Yasuma

Wataru Takahashi

A change-over valve including a valve housing defining an inlet port for receiving fluid from a fluid pressure supply, a first outlet port for feeding operating fluid to a first fluid responsive actuator, a second outlet port for feeding operating fluid to a second fluid responsive actuator, and drain port means for draining fluid to a fluid reservoir; and a spool retained by the housing and movable therein between first and second positions, the housing and the spool in its first position providing communication between the inlet port and the first outlet port and preventing communication between the inlet port and the second outlet port, and the housing and the spool in its second position providing communication between the inlet port and the second outlet port, and preventing communication between the inlet port and the first outlet port. Also included is a control valve movable between open and closed positions in response to the fluid pressure at the first outlet port, the control valve providing communication between the second outlet port and the drain port means when in its open position and preventing communication therebetween when in its closed position.

Change-over valve

There is disclosed a solenoid-operated selector valve adapted for control of hydraulic clutches such as of a tractor. The selector valve has four ports and can assume two positions. The selector valve includes a spool having an axially extending hole. A piston and a sequence valve are held in this hole. The sequence valve can relieve the pressure. The hole is in communication with the outside of the spool via first through third radially extending holes. The pressure inside one cylinder port which is normally connected with the pump port is maintained constant even when the engaged clutch is being switched to the other. This pressure is not reduced down to zero until the pressure inside the other cylinder port reaches a predetermined pressure.

Solenoid-operated selector valve

A spool control valve in which communicating passages are provided in the spool to communicate between a pair of locations in the spool passage and filter means are provided in a communicating passage to prevent valve orifices being blocked by particles of foreign matter in the fluid.

Spool control valve

An operating oil introduction type electromagnetic valve comprising a cap defining an electromagnetic valve external portion, an exciting coil, an inner housing and a stopper spacedly disposed inside the coil, a tubular slide guide with a bottom surface which is made of a non-magnetic material and disposed inside the inner housing and stopper, a plunger chamber formed within the guide and communicating at one end with an oil source and with the other end closed, and a plunger slidably contained within the plunger chamber and actuated by electromagnetic force of the coil.

Operating oil introduction type electromagnetic valve

A solenoid for an electromagnetic valve which has an exciting coil, a tubular hollow inner housing with a shaft sleeve portion thereof disposed within the coil, a tubular slide guide having a bottom made of a non-magnetic material which is contained within the housing, a stopper with a stationary shaft portion fitted in an opening end of the slide guide, and a plunger slidably contained within the slide guide which is defined by the end face of the shaft portion and the bottom marginal portion of the slide guide.

Solenoid for electromagnetic valve

An electromagnetic proportional actuator comprises a plunger axially movably received in a cylindrical housing. An actuating member has one end thereof abutting against or connected to one axial end of the plunger. The plunger is displaced in response to electric current passing through a solenoid wound around an outer peripheral surface of the housing. A tubular member formed of a non-magnetic material is disposed between an outer peripheral surface of the plunger and an inner peripheral surface of the housing in such a manner that the plunger is axially slidable within the tubular member, to prevent the plunger from being attracted to the inner peripheral surface of the housing.

Growing community of inventors

Saitama, Japan

Koji Ichihashi