Plunger or piston pump with inner annular gap - has membrane assembly of two stacked roll membranes, which can be pushed into each other

摘要

The pump has a working chamber between intake and pressure valves, which is located in an annular gap between the piston and housing. It is separated from a collecting chamber, connected to pump intake side, via a high pressure seal. The collecting chamber is sealed by a roll membrane. The membrane assembly (8,9) consists of at least two membranes, positioned on top of each other. The cylindrical sections of the membranes have such different dias. that the membranes may be pushed freely into each other axially. The free edges of the cylindrical sections have integral annular flanges (10,11), sealed in grooves in the piston (1) and housing (3). ADVANTAGE - Low-cost design and increased leakage prevention.