Abstract: A trochoid oil pump, which enables the endurance to be increased and the reduction of discharge pulsations and noise to be achieved, and in which those results can be realized with a very simple structure. An interdental space constituted by an inner rotor and an outer rotor having trochoid tooth profile or substantially trochoid tooth profile starts a compression stroke in the location of a partition section between an intake port and a discharge portion, and a linking gap L is composed by the interdental space and a preceding adjacent interdental space realized in a discharge stroke. The linking gap expands gradually from the start of compression stroke to the discharge stroke.

Abstract: The present invention provides an oil pump in which eroding of the inside of the pump due to cavitation and erosion is prevented by minimizing the pressure change in a fluid when inter-tooth spaces formed by an inner rotor and an outer rotor transport the fluid from the intake port to the discharge port. The oil pump comprises: an inner rotor; an outer rotor; an intake port; a discharge port; a transfer side partition part formed between a terminal end of the intake port and a leading end of the discharge port; and a shallow groove which is formed in the transfer side partition part, and which communicates with the discharge port but does not communicate with the intake port. The shallow groove does not intersect with the cell on the transfer side partition part, and is positioned farther inward than the circular locus of the gear bottom parts of the inner rotor.

Abstract: A relief valve mounted on a pump such as an oil pump, for preventing pressure abnormality by allowing fluid to escape when a discharge fluid pressure reaches a predetermined set value, wherein influx of oil sludge into the valve can be prevented. The relief valve comprises: a valve housing; and a guide inflow path which is in the same direction as a slide direction of a valve main body that slides along a valve guide path of the valve housing under a predetermined pressure and which provides communication between a discharge flow path and the valve guide path. The valve guide path is arranged so that a relief opening part thereof is closed downwardly by the valve main body. The valve guide path and the guide inflow path are arranged above an orthogonal cross section of the discharge flow path.

Abstract: It is an object of the present invention to provide a trochoid type oil pump in which erosion of the rotor surfaces caused by cavitation is minimized, vibration and noise are reduced, and the structure is greatly simplified. The trochoid type oil pump of the present invention comprises a rotor chamber which has an intake port and a discharge port, an outer rotor, an inner rotor, and shallow grooves which are formed on the side of the initial end portion of the discharge port on the circular circumference of the track of the positions of the bottom portions of the teeth created by the rotation of the outer rotor. In a state in which the sealed spaces formed by the outer rotor, the inner rotor and a partition part between the final end portion of the intake port and the initial end portion of the discharge port are reduced in volume from the maximum volume, the sealed spaces Sa are caused to communicate with the shallow grooves.

Abstract: The present invention provides an oil pump in which eroding of the inside of the pump due to cavitation and erosion is prevented by minimizing the pressure change in a fluid when inter-tooth spaces formed by an inner rotor and an outer rotor transport the fluid from the intake port to the discharge port. The oil pump comprises: an inner rotor; an outer rotor; an intake port; a discharge port; a transfer side partition part formed between a terminal end of the intake port and a leading end of the discharge port; and a shallow groove which is formed in the transfer side partition part, and which communicates with the discharge port but does not communicate with the intake port. The shallow groove does not intersect with the cell on the transfer side partition part, and is positioned farther inward than the circular locus of the gear bottom parts of the inner rotor.

Abstract: A trochoid oil pump, which enables the endurance to be increased and the reduction of discharge pulsations and noise to be achieved, and in which those results can be realized with a very simple structure. An interdental space constituted by an inner rotor and an outer rotor having trochoid tooth profile or substantially trochoid tooth profile starts a compression stroke in the location of a partition section between an intake port and a discharge portion, and a linking gap L is composed by the interdental space and a preceding adjacent interdental space realized in a discharge stroke. The linking gap expands gradually from the start of compression stroke to the discharge stroke.

Abstract: It is an object of the present invention to provide a trochoid type oil pump in which erosion of the rotor surfaces caused by cavitation is minimized, vibration and noise are reduced, and the structure is greatly simplified. The trochoid type oil pump of the present invention comprises a rotor chamber which has an intake port and a discharge port, an outer rotor, an inner rotor, and shallow grooves which are formed on the side of the initial end portion of the discharge port on the circular circumference of the track of the positions of the bottom portions of the teeth created by the rotation of the outer rotor. In a state in which the sealed spaces formed by the outer rotor, the inner rotor and a partition part between the final end portion of the intake port and the initial end portion of the discharge port are reduced in volume from the maximum volume, the sealed spaces Sa are caused to communicate with the shallow grooves.