Abstract: A gear machining apparatus creates a gear on a workpiece W by moving a gear cutting tool relatively with respect to the workpiece along the direction of the rotation axis of the workpiece W while synchronously rotating the gear cutting tool and the workpiece. One of a workpiece rotation speed controlling portion and a tool rotation speed controlling portion varies the rotation speed of one of the workpiece and the gear cutting tool and the other one of the workpiece rotation speed controlling portion and the tool rotation speed controlling portion synchronizes the rotation speed of the other one of the workpiece and the gear cutting tool with one of the rotation speed of the workpiece and the gear cutting tool.

Abstract: A gear machining apparatus creates a gear on a workpiece W by moving a gear cutting tool relatively with respect to the workpiece along the direction of the rotation axis of the workpiece W while synchronously rotating the gear cutting tool and the workpiece. One of a workpiece rotation speed controlling portion and a tool rotation speed controlling portion varies the rotation speed of one of the workpiece and the gear cutting tool and the other one of the workpiece rotation speed controlling portion and the tool rotation speed controlling portion synchronizes the rotation speed of the other one of the workpiece and the gear cutting tool with one of the rotation speed of the workpiece and the gear cutting tool.

Abstract: A grinding wheel includes: a plurality of abrasive grains arranged so as not to contact with one another; interval adjustment materials interposed between the abrasive grains, arranged in contact with the abrasive grains, and having a grain size that allows a distance between the abrasive grains to be equal to a minimum separation distance; a binder that binds each of the abrasive grains to the interval adjustment materials; and pores formed between the abrasive grains.

Abstract: In an internal gear pump that includes an inner gear having outer teeth and an outer gear having inner teeth, either the inner or outer teeth have a shape based on a tooth shape that is respectively formed by a generating curve of the outer or inner teeth. The inner teeth are arc-shaped, the outer teeth are curved-shaped, and both end sections of the curved shape are arc-shaped. If a radius of the arc shape of the inner teeth is set as ro, a radius of the arc shape of each of the corner sections is set as ri, a diameter of a pitch circle of the inner teeth is set as dp, and the number of the inner teeth is set as z, the inner gear and the outer gear each has a shape that satisfies a relationship established by following equations: 1.6>ro/(dp/z)>1.0; and ro/(dp/z)>ri/(dp/z)?0.13.

Abstract: An electric pump includes: a second housing and a first housing separated from each other in an axial direction; a stator portion that accommodates an annular coil portion; an outer rotor portion that is rotated based on a magnetic field generated by the coil portion, at a position on the inner side of the housings; and an inner rotor that is rotatably supported by a support shaft portion having an axis that is offset from that of the outer rotor portion, and that has an outer peripheral surface that is engaged with an inner peripheral surface of the outer rotor portion. The second housing is fitted onto the support shaft portion, to which the first housing has been fixed, from one side of the support shaft portion in the axial direction. As a result, the outer rotor portion and the stator portion are clamped between the first housing and the second housing from both sides in the axial direction.

Abstract: An electric pump includes: a second housing and a first housing separated from each other in an axial direction; a stator portion that accommodates an annular coil portion; an outer rotor portion that is rotated based on a magnetic field generated by the coil portion, at a position on the inner side of the housings; and an inner rotor that is rotatably supported by a support shaft portion having an axis that is offset from that of the outer rotor portion, and that has an outer peripheral surface that is engaged with an inner peripheral surface of the outer rotor portion. The second housing is fitted onto the support shaft portion, to which the first housing has been fixed, from one side of the support shaft portion in the axial direction. As a result, the outer rotor portion and the stator portion are clamped between the first housing and the second housing from both sides in the axial direction.