Title:
RECIPROCATING PUMP
Document Type and Number:
Japanese Patent JP3874416
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a reciprocating pump which can smoothly close valves and surely avoid improper operation such as chattering even adopting spring type check valves with springs made of resin with less spring force expected.
SOLUTION: A pump body 3 is formed with an inlet passage 1 and a discharge passage 2 for fluid to be transferred. A bellows 6 of a bottomed cylinder shape is integrally connected to an axial rear side of the body and defines a sealed space 7. The inlet passage 1 is equipped with an upstream portion 1A of a large diameter having a predetermined passage cross-sectional area and downstream portions 1B, 1B of a small diameter with reduced cross-sectional passage area and bifurcated in a forked Y shape. At outlets of these small-diameter downstream portions 1B, 1B, two small, spring type first check valves 15, 15 are arranged side by side and attached, with reduced pressure receiving area corresponding to the reduced cross-sectional passage area of the small-diameter downstream portions 1B, 1B. Outlets of these first check valves 15, 15 are respectively opened into the sealed space 7.
Inventors:
Kawamura Hitoshi
Application Number:
JP2003127168A
Publication Date:
January 31, 2007
Filing Date:
May 02, 2003
Export Citation:
Assignee:
Nippon Pillar Industry Co., Ltd.
International Classes:
F04B43/08; F04B53/10; F04B11/00; F04B43/10; F04B43/113; F04B53/16; (IPC1-7): F04B43/08; F04B43/10; F04B53/10
Domestic Patent References:
| JP2001153052A | ||||
| JP3249315A |
Attorney, Agent or Firm:
Shoji Suzue
Toshiyuki Kimura
Toshiyuki Kimura