| 摘要 |
PROBLEM TO BE SOLVED: To simplify the valve structure and increase the delivery volume in a pump provided with a pushing-down nozzle, by sequentially providing a suction valve and a delivery valve at the lower end of a cylinder. SOLUTION: A cylinder 3 is water-tightly inserted into an external cylinder 1 extending down a suction pipe 2 and a tubular plunger 5 provided with a piston 6 at the lower end is extended down from the pushing-down nozzle head 4 arranged above the cylinder 3 and the piston 6 is inserted in the cylinder 3 so as to freely slide up and down. A delivery passage 8 connecting the lower end of the cylinder to the nozzle 7 of the pushing-down nozzle head 4 is formed between the external cylinder 1 and the cylinder 3 or in the tubular plunger 5 and a suction passage 9 connecting the suction pipe to the lower end in the cylinder is formed at the lower end of the external cylinder. A suction valve 10 opening/closing the suction passage and a delivery valve 11 opening/closing the delivery passage are formed with a serial valve member 17 at the lower end in the external cylinder. A preventive means 12 against a negative pressure in the container is provided in the external cylinder and the upper part of the cylinder and a fitting cylinder 13 is provided at an appropriate position of the outer periphery of the external cylinder. |
