Patent ID: 11971031
Assignee: GREE ELECTRIC APPLIANCES, INC. OF ZHUHAI
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 17:
18. A pump body assembly, comprising:
a piston;
a shaft;
a piston sheath, the shaft driving the piston to rotate and reciprocate in the piston sheath while rotating; and
a cylinder comprising an exhaust channel, the piston sheath being located in the cylinder, wherein a compression chamber is defined between an outer circumferential wall of the piston and an inner wall of the cylinder, and a pressure relief recess is defined in the outer circumferential wall of the piston such that, on a condition that the pump body is in an exhaust process, gas which is in the compression chamber and away from the exhaust channel is capable of being discharged from the exhaust channel through the pressure relief recess;
wherein the pressure relief recess extends along a circumferential direction of the piston.