Abstract: An electromagnetic valve includes a sleeve having a valve hole at a central portion thereof, a spool, and an electromagnetic solenoid. The sleeve has plural ports penetrating the sleeve between inner and outer peripheral surfaces thereof and disposed side by side in a central axis direction of the valve hole. In the spool, plural lands having an outer peripheral surface facing an inner peripheral surface of the valve hole are provided side by side in the central axis direction. The electromagnetic solenoid is configured to move the spool in the central axis direction in the valve hole. The ports have one or plural recessed portions in which working oil is stored. When the spool is decentered with respect to the sleeve, a pressure of the working oil stored is increased.

Abstract: An electromagnetic valve includes a sleeve having a valve hole at a central portion thereof, a spool, and an electromagnetic solenoid. The sleeve has plural ports penetrating the sleeve between inner and outer peripheral surfaces thereof and disposed side by side in a central axis direction of the valve hole. In the spool, plural lands having an outer peripheral surface facing an inner peripheral surface of the valve hole are provided side by side in the central axis direction. The electromagnetic solenoid is configured to move the spool in the central axis direction in the valve hole. The ports have one or plural recessed portions in which working oil is stored. When the spool is decentered with respect to the sleeve, a pressure of the working oil stored is increased.

Abstract: In a gear pump, an outer rotor and an inner rotor are disposed in a rotor installation chamber defined by a pump body and a pump cover. A suction port groove and a discharge port groove are formed in at least one of the pump body and the pump cover. A narrowing portion is formed at a portion of a radially outer side wall portion of the suction port groove, the portion being close to a terminal end wall portion of the suction port groove. The narrowing portion narrows the groove width in the radial direction. A pressurizing region that pressurizes oil in the gear chamber is formed between the narrowing portion and the terminal end wall portion.

Abstract: In a gear pump, an outer rotor and an inner rotor are disposed in a rotor installation chamber defined by a pump body and a pump cover. A suction port groove and a discharge port groove are formed in at least one of the pump body and the pump cover. A narrowing portion is formed at a portion of a radially outer side wall portion of the suction port groove, the portion being close to a terminal end wall portion of the suction port groove. The narrowing portion narrows the groove width in the radial direction. A pressurizing region that pressurizes oil in the gear chamber is formed between the narrowing portion and the terminal end wall portion.