PURPOSE: To damp the extent of pressure pulsation to be produced in a pump part by installing a pipe after connecting one end to one side out of an inlet conducting a fluid into a motor part from the pump part and an outlet deriving the fluid in the motor part to the outside, and getting the other end opposed to the other side, respectively.
CONSTITUTION: When an armature 5 is rotated, a rotor 1 is also rotated, and a ball 3 reciprocates in the inner part of a cylinder 11 by means of an eccentric action. In consequence, this cylinder 11 is selectively interconnected to an inlet passage 21 and a discharge passage 22, so that a cylinder chamber performs both inlet and discharge actions. Accordingly, a fluid in the cylinder chamber is led to a cavity 9 by way of an interconnecting passage 71 of a pump housing 7 and another interconnecting passage 101 of a pipe 10, and then it is discharged to an outside discharge passage 811 in a left end 81 of a motor housing 8. At this time, pressure pulsation to be produced in this discharged fluid is damped by a pulsation damper made up of the pipe 10, whose one end is connected to the interconnecting passage 71 and the other end is opposed to the outside discharge passage 811, and the cavity 9.
USAMI HIROYUKI
ITO AKIRA
TAKEI TOSHIHIRO
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