Closable dispensing pump for fluid substances withdrawable from a container

Abstract

A closable dispensing pump for fluid substances comprising a chamber in which a piston is slidable, drivable by a stem, said stem presenting in its interior at least one first passage communicating with said compression chamber and a dispensing pushbutton presenting a second passage opening towards the outside of said dispensing pushbutton. The first passage presents a first aperture which opens onto said first contacting surface, said second passage presenting a second aperture which opens onto said second contacting surface, said pushbutton and said stem being mutually rotatable about a longitudinal axis between at least one open position in which said first and second aperture face each other and are in mutual communication, and a closed position in which they are mutually isolated and displaced.

1 . A closable dispensing pump for fluid substances withdrawable from a container, comprising a cup-shaped body defining a chamber in which a piston is slidable, drivable by a stem, the cup-shaped body presents at least one intake hole closed by at least one first valve and communicating via a dip tube with the interior of the container, said stem presenting in its interior at least one first passage communicating, via at least one second valve with said chamber and being slidably mounted through an endpiece which closes said cup-shaped body, and a dispensing pushbutton presenting, for dispensing the fluid substance, a second passage opening towards the outside of said dispensing pushbutton, said stem presenting a first contacting surface cooperating substantially sealedly and by contact with a second contacting surface of said dispensing pushbutton, wherein said first passage presents a first aperture which opens onto said first contacting surface, said second passage presenting a second aperture which opens onto said second contacting surface, said pushbutton and said stem being mutually rotatable about a longitudinal axis between at least one open position in which said first and second aperture face each other and are in mutual communication, and a closed position in which they are mutually isolated and displaced. 
     
     
         2 . A pump as claimed in  claim 1 , wherein said first surface and second surface are frontal surfaces of said pushbutton and said stem. 
     
     
         3 . A pump as claimed in  claim 2 , wherein said first aperture is in a position offset from an axis of said stem. 
     
     
         4 . A pump as claimed in  claim 2 , wherein said second aperture is provided in a position offset from an axis of said dispensing pushbutton. 
     
     
         5 . A pump as claimed in  claim 1 , wherein said first passage is an axial hole provided in a position offset from said stem axis. 
     
     
         6 . A pump as claimed in  claim 1 , wherein said first surface and second surface are lateral surfaces of said pushbutton and said stem. 
     
     
         7 . A pump as claimed in  claim 6 , wherein said first passage is a lateral groove provided at the top of the stem, and faces both the upper edge of the stem and, with an aperture, the lateral outer surface of the stem. 
     
     
         8 . A pump as claimed in  claim 7 , wherein said top of the stem is open. 
     
     
         9 . A pump as claimed in  claim 6 , wherein said second passage is a hole which opens directly onto the lateral surface defining the cavity housing the stem. 
     
     
         10 . A pump as claimed in  claim 1 , wherein said stem and said endpiece are torsionally rigid. 
     
     
         11 . A pump as claimed in  claim 8 , wherein said endpiece presents, at a stem guide surface thereof, a projection cooperating with a grove provided in the stem. 
     
     
         12 . A pump as claimed in  claim 1 , wherein said dispensing pushbutton and said endpiece each present at least one abutment which, when the pushbutton is in its closed position, mutually cooperate to block the stroke of said pushbutton and hence of the stem. 
     
     
         13 . A pump as claimed in  claim 2 , wherein the pushbutton presents a pair of abutments radially projecting from the body of the pushbutton, the endpiece presenting a pair of cylindrical abutments, each being separated by a pair of grooves, each of which receives an abutment of the pushbutton during the pushbutton stroke when the pushbutton is in its open position. 
     
     
         14 . A pump as claimed in  claim 1 , wherein a cut-out is provided in that surface defining the pushbutton cavity, on the stem surface a rib being provided which becomes inserted into said cut-out when the stem and pushbutton are connected together, said cut-out and said rib cooperating to facilitate alignment between the first and second aperture when the pump is in its open position, and to limit rotation between the pushbutton and stem.