| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique enabling the intrusion of foreign matters between a rotor and a shaft to be suppressed.SOLUTION: A motor-driven water pump includes a rotor 60 rotatably mounted on a shaft. The rotor 60 includes a body 62 having an inner circumferential surface making a circle of the shaft, and a magnet 66 arranged at a clearance between itself and the outer circumferential surface of the body 62. The clearance between the outer circumferential surface of the body 62 and the magnet 66 communicates a motor chamber with a low-pressure region of a pump chamber. The body 62 includes a lubrication groove 70 extending from the end on the motor-chamber side of the inner circumferential surface of the body 62 along the shaft 16 to the pump chamber. The rotor 60 is arranged in the clearance between the outer circumferential surface of the body 62 and the magnet 66 and at a position different from the lubrication groove 70 in the rotating direction of the rotor 60. The rotor 60 further includes a barrier 64 extending from the end on the motor-chamber side of the outer circumferential surface of the body 62 toward the pump chamber.SELECTED DRAWING: Figure 2 |
