Patent ID: 7074014
Filing Date: 2006-07-11
Classification: F04D,Y10T

Abstract:
1. A dipping type pump where gas is discharged at a time of actuation, which is constituted such that a rotary shaft is provided inside a pump casing having a portion dipped in liquid, a plurality of impellers are mounted to the rotary shaft, and liquid is sucked from a sucking port at a lower portion of the pump casing and discharged from a discharging port by rotating and driving the rotary shaft by a motor, wherein a check valve for allowing outflow of gas from the casing but preventing outflow of liquid from the casing is provided at an upper position of the pump casing, wherein the check valve comprises a valve chamber provided with a relief valve seat communicating with a relief port, and only one spherical valve body movably accommodated in the valve chamber, wherein the relief valve seat is made of such hard material as metal or ceramic and is provided at a position of an upper end portion of the valve chamber, and the valve body is made of hard material having a specific gravity larger than that of the liquid and is accommodated in the valve chamber movably in a vertical direction, and the valve body opens the relief valve seat in ordinary operation and is constituted such that the valve body is not pushed and moved toward a position closing the relief valve seat by gas flowing from the casing into the valve chamber but is pushed and moved toward the position closing the relief valve seat by liquid flowing into the valve chamber.