Patent ID: 7562794
Filing Date: 2009-07-21
Classification: B65B

Abstract:
1. A pump, comprising: a piston/cylinder assembly that can be connected to a container so that a pressure in said container is reduced with respect to a pressure outside of said container by actuation of a piston in said piston/cylinder assembly, said piston/cylinder assembly being provided with a plate-like part, arranged in the piston, which adopts at least two positions as a function of a pressure difference between an inside of said container and said outside of said container, a sealing part provided on an outer surface of said piston and providing a sealing between said piston and said cylinder, said sealing part being separate from said plate-like part, said plate-like part not sealing said piston and said cylinder, the at least two positions including a first position wherein there is little or no said pressure difference, and a second position, which is displaced with respect to the first position, wherein the pressure difference has been increased or reduced, said plate-like part configured to generate an audible indication of the displacement from the first position to the second position or vice versa.