Simplified metering pump

Abstract

A metering pump including a main body having a first surface, a member for attachment to a bottle, an inlet valve, an elastomeric head having a second surface, where both surfaces define a pumping chamber, and a discharge valve having a valve seat and a moving member adapted to move between a first closed position and a second open position. The moving member extends from the head forming a partition and is integral with the head. The first and second surfaces are relatively movable therebetween causing pumping of a liquid. When the moving member is in the first position and there is a reduced pressure in the pumping chamber, the reduced pressure then presses the moving member against the valve seat.

1 . A metering pump comprising: (a) a main body having a first surface, (b) first means for attachment to a bottle neck, (c) second means for attachment of a dip tube, (d) an inlet valve, (e) a head, where said head has a second surface facing said first surface, and where said first surface and said second surface define a pumping chamber, where said head is made from a material having elastomeric properties adapted to be resiliently deformed by a manually applied force and has an external actuation surface adapted to be deformed by a user's finger, and (f) a discharge valve at the outlet of said pumping chamber, where said discharge valve includes a valve seat and a moving member adapted to move between a first position, corresponding to said closed discharge valve and in which said moving member contacts said valve seat, and a second position, corresponding to said open discharge valve, where said moving member extends from said head forming a partition, where said moving member is integral with said head, and where said first surface and said second surface are adapted to perform a relative movement therebetween causing the pumping of a liquid between said inlet valve and said discharge valve, wherein when said moving member is in said first position, and there is a reduced pressure in said pumping chamber, said reduced pressure then exerts a force pressing said moving member against said valve seat.  
   
   
       2 . The pump of  claim 1 , wherein said partition is a flat surface.  
   
   
       3 . The pump of  claim 1 , wherein said partition is a cylindrical surface.  
   
   
       4 . The pump of  claim 1 , wherein said partition is a cylinder surrounding said second surface.  
   
   
       5 . The pump of  claim 4 , wherein said valve seat is formed by a second also cylindrical partition disposed in said main body, where said second partition surrounds said first surface.  
   
   
       6 . The pump of  claim 1 , wherein said second surface is convexely curved towards an outside of said pumping chambers, and is a spherical cap.  
   
   
       7 . The pump of  claim 1 , wherein said first surface has a concavely curved portion towards an interior of said pumping chamber, and is a spherical portion.  
   
   
       8 . The pump of  claim 7 , wherein said curved portion and said second surfaced make contact in a limit of the stroke followed by said second surface during a pumping movement.  
   
   
       9 . The pump of  claim 8 , wherein said curved portion has an external rim that is convex towards the interior of said pumping chamber.  
   
   
       10 . The pump of  claim 1 , wherein said valve seat has a rounded contact surface with said moving member.  
   
   
       11 . The pump of  claim 1 , wherein said moving member has a contact portion with said valve seat having a thickness tapering down towards a free end thereof.  
   
   
       12 . The pump of  claim 1 , having at least one column on said first surface extending towards said second surface and which is disposed at a portion proximate said discharge valve.  
   
   
       13 . The pump of  claim 12 , wherein said at least one column has a height such as to contact said second surface when said second surface is in an extended position thereof.  
   
   
       14 . The pump  claim 1  further comprising: an attachment body including said first attachment means, where said attachment body is attached to said main body for relative displacement between an open position and a closed position, and wherein said attachment body includes a projection which, when said attachment body and said main body are in the closed position, prevents said second surface from performing said relative movement.  
   
   
       15 . The pump of  claim 14 , wherein said projection is a tubular stem surrounding said inlet valve.  
   
   
       16 . The pump of  claim 14 , wherein said projection is hermetically sealed against said second surface when said attachment body and said main body are in said closed position.  
   
   
       17 . The pump of  claim 14 , wherein said relative displacement is greater than said relative movement.  
   
   
       18 . The pump of  claim 15 , wherein said main body includes a first annular lip forming a hermetic seal with the outer wall of said tubular stem.  
   
   
       19 . The pump of  claim 18 , wherein said main body includes a second annular lip forming a hermetic seal with an annular partition disposed in said attachment body, said annular partition surrounding a ventilation hole.