Patent ID: 6382471
Filing Date: 2002-05-07
Classification: B05B

Abstract:
A pump for dispensing a substance comprising:a support, a moving member mounted to move relative to said support, a diaphragm, said moving member having a duct in which the substance to be dispensed penetrates via at least one opening, said support co-operating with the moving member to define a variable-volume pump chamber around said duct, said diaphragm being held by retaining means on the support and in which one end of said duct is inserted, said diaphragm having a valve-forming portion arranged to isolate the pump chamber from said opening(s) of the duct while the volume of the pump chamber is increasing and the substance is being sucked into the pump chamber, said diaphragm also bearing against the moving member in such a manner that movement of the moving member to dispense the substance causes the diaphragm to be stretched elastically, said pump having means suitable, during movement of the moving member for dispensing the substance, for minimizing the stretching of the valve-forming portion of said diaphragm.