Patent Publication Number: US-10773269-B2

Title: Dispensing pump with skirt spring

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This Application is a continuation of U.S. application Ser. No. 15/105,646, filed Jun. 17, 2016, which is a Section 371 National Stage Filing of PCT/US2014/072932 filed Dec. 31, 2014 (now expired), which claims the benefit of US Provisional Application No. 61/926,486 filed Jan. 13, 2014 (now expired). 
    
    
     BACKGROUND OF THE INVENTION 
     (1) Field of the Invention 
     The instant invention relates to a dispensing pump for liquids, viscous flowable materials, foams, gels, etc. and more particularly to a dispensing pump with a skirt-shaped plastic spring. 
     (2) Description of Related Art 
     Dispensing pumps are generally known in the art. They generally comprise a body portion which is seated on the neck of a container, a co-acting nozzle portion which slides relative to the body portion, and a spring structure which biases the co-acting nozzle portion to its normal rest position. To dispense the material in the container, the user manually depresses the nozzle which forces the material from the inside of the body portion. When the nozzle is released, the spring forces the nozzle portion back to its normal resting position. 
     SUMMARY OF THE INVENTION 
     An exemplary embodiment of a dispensing pump according to the present invention generally comprises a base portion, an inlet valve, a piston valve, a resilient polymer skirt spring, a spring guide and a pump actuator. 
     The base portion has a bottom wall and an upwardly extending sidewall. The bottom wall includes a centrally located entrance orifice which is received in communication with the neck of a container (not shown) having the material to be dispensed held within. The base portion further has a flow conduit extending upwardly from the inner surface of the bottom wall which surrounds the entrance orifice. 
     The inlet valve is received within the entrance orifice and is slidably movable between a normal closed position where the inlet valve is seated within the entrance orifice and an open position where the inlet is unseated from the entrance orifice to allow material to flow into the flow conduit from the container. 
     The piston valve has a lower end received within the flow conduit, an upper end and an outlet opening adjacent the upper end. 
     The skirt spring comprises a plurality of concentric nesting rings sequentially decreasing in diameter from a base ring to a top ring wherein adjacent rings are each interconnected by a pair of spaced opposing bridge segments. In order to provide spring force, the bridge segments are staggered at each sequential ring to provide cantilevered segments as the rings nest together in compression. In the exemplary embodiment, the opposing bridge segments are spaced 180 degrees apart at each tier. Further, the opposing bridge segments are staggered 90 degrees at each sequential ring tier. In accordance with the teachings of the invention, the skirt spring is preferably molded from a polymer material similar to that of the other pump structures so that the entire dispensing pump can be easily recycled. The metal springs in prior art devices forced disassembly of the pump prior to recycling and thus restricted both use and disposal of the prior art device. 
     The skirt spring further includes an upper wall portion extending inwardly from the top ring and an inner annular piston wall extending downwardly from the upper wall. The skirt spring is received within the base portion with the base ring seated on the bottom wall, and such that the upper end of the piston valve is concentrically received within the inner piston wall, and further such that the outer surface of the inner piston wall is disposed concentrically within the flow conduit. In this regard, the piston valve is slidably movable within the flow conduit and within the inner piston wall, and the upper end of the piston valve engages and cooperates with the inner piston wall to form an outlet valve. 
     The guide structure has a top wall, an outer sidewall depending downwardly and outwardly from the top wall, and an inner annular wall depending downwardly from the top wall. The top wall also includes an outlet orifice located within the inner annular wall. The guide structure is received within the base portion wherein the terminal outer edge of the outer sidewall is slidably received within the outer sidewall of the base portion, and the inner annular wall captures the top ring of the skirt spring. This arrangement permits the guide structure to be slidably movable within the base portion and to guide compression and expansion of the skirt spring. 
     The pump actuator includes a top wall, downward depending sidewalls and a dispensing orifice with an internal conduit. The pump actuator is received over the guide structure and within the sidewall of the base portion where the internal conduit of the dispensing orifice communicates with the outlet orifice of the guide structure and the pump actuator is slidably movable relative to the base portion. 
     In operation, forcible downward compression of the pump actuator causes a corresponding downward movement of the guide structure, a corresponding guided compression of the skirt spring, a corresponding sliding movement of the inner piston wall of the skirt spring relative to the upper end of the piston valve to open the outlet valve and a corresponding downward sliding movement of the piston valve to force material within the flow conduit to flow through the outlet valve, through the outlet orifice of the guide structure and finally out through the dispensing orifice of the nozzle. 
     Upon the subsequent release of the pump actuator, the skirt spring expands causing a forcible upward movement of the guide structure and pump actuator, a corresponding sliding movement of the inner piston wall of the skirt spring relative to the upper end of the piston valve to close the outlet valve, and a corresponding upward sliding movement of the piston valve, which in turn creates a vacuum pressure within the flow conduit drawing the inlet valve from its normally closed position to its open position and drawing material into the flow conduit through the inlet orifice. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       While the specification concludes with claims particularly pointing out and distinctly claiming particular embodiments of the instant invention, various embodiments of the invention can be more readily understood and appreciated from the following descriptions of various embodiments of the invention when read in conjunction with the accompanying drawings in which: 
         FIG. 1  is a cross-sectional view of an exemplary embodiment of the dispensing pump of the present invention; 
         FIG. 2  is a perspective view of the skirt spring thereof; 
         FIG. 3  is a cross-section view thereof taken along line  3 - 3  of  FIG. 2 ; and 
         FIG. 4  is a top view thereof. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, an exemplary embodiment of the invention is generally indicated at  10  in  FIG. 1 . According to the present invention, the dispensing pump  10  generally comprises a base portion  12 , an inlet valve  14 , a piston valve  16 , a resilient polymer skirt spring  18 , a spring guide  20  and a pump actuator  22 . 
     The base portion  12  has a bottom wall  24  and an upwardly extending sidewall  26 . The bottom wall  24  includes a centrally located entrance orifice  28  which is received in communication with the neck of a container (not shown) having the material (not shown) to be dispensed held within. The dispensing pump  10  is useful for a variety of flowable materials, including, not limited to liquids, viscous flowable fluids, foams, gels, etc. The base portion  12  further has a flow conduit  30  extending upwardly from the inner surface of the bottom wall  24  which surrounds the entrance orifice  28 . 
     The inlet valve  14  is received within the entrance orifice  28  and is slidably movable between a normal closed position where the inlet valve  14  is seated within the entrance orifice  28  and an open position where the inlet valve  14  is unseated from the entrance orifice  28  to allow material to flow into the flow conduit  30  from the container. 
     The piston valve  16  is generally cylindrical and has a lower end  32  received within the flow conduit  30 , an upper end  34  and an outlet opening  36  adjacent the upper end  34 . 
     The skirt spring  18  comprises a plurality of concentric nesting rings  38  sequentially decreasing in diameter from a base ring  38 A to a top ring  38 F wherein adjacent rings are each interconnected by a pair of spaced opposing bridge segments  40 A, 40 B. The inner and outer diameters of adjacent rings ( 38 A- 38 B) are configured so that the smaller upper ring  38 B can collapse and nest within the larger lower ring  38 A. In order to provide spring force, the bridge segments  40  are staggered at each sequential ring to provide cantilevered spring segments as the rings  38  nest together in compression. In the exemplary embodiment, the opposing bridge segments  40  are spaced 180 degrees apart at each tier (see  FIG. 4 ). Further, the opposing bridge segments  40  are staggered 90 degrees at each sequential ring tier (see also  FIG. 4 ). In accordance with the teachings of the invention, the skirt spring  18  is preferably molded from a polymer material (such as polypropylene) similar to that of the other pump structures so that the entire dispensing pump  10  can be assembled from all plastic parts and thus, easily recycled. The metal spring in prior art devices forced disassembly of the pump prior to recycling and thus restricted both use and disposal of the prior art device. The nesting construction of the rings  38  reduces pump height and allows single action injection molding which is simple and cost effective. 
     The skirt spring  18  further includes an upper wall portion  42  extending inwardly from the top ring  38 F and an inner annular piston wall  44  extending downwardly from the upper wall portion  42 . The skirt spring  18  is received within the base portion  12  with the base ring  38 A seated on the bottom wall  24 , and such that the upper end  34  of the piston valve  16  is concentrically received within the inner piston wall  44 , and further such that the outer surface of the inner piston wall  44  is disposed concentrically within the flow conduit  30 . In this regard, the piston valve  16  is slidably movable within the flow conduit  30  and within the inner piston wall  44 , and the upper end  34  of the piston valve  16  engages and cooperates with the inner piston wall  44  to form an outlet valve. 
     The guide structure  20  has a top wall  46 , an outer sidewall  48  depending downwardly and outwardly from the top wall  46 , and an inner annular wall  50  depending downwardly from the top wall  46 . The top wall  46  also includes an outlet orifice  52  located within the inner annular wall  50 . The guide structure  20  is received within the base portion  12  wherein the terminal outer edge of the outer sidewall  48  is slidably received within the outer sidewall  26  of the base portion, and the inner annular wall  50  captures the top ring  38 F of the skirt spring  18 . This arrangement permits the guide structure  20  to be slidably movable within the base portion  12  and to guide compression and expansion of the skirt spring  18 . 
     The pump actuator  22  includes a top wall  54 , downward depending sidewalls  56  and a dispensing orifice  58  with an internal conduit  60 . The pump actuator  22  is received over the guide structure  20  and within the sidewall  26  of the base portion  12  where the internal conduit  60  of the dispensing orifice  58  communicates with the outlet orifice  52  of the guide structure  20  and the pump actuator  22  is slidably movable relative to the base portion  12 . 
     In operation, forcible downward compression of the pump actuator  22  causes a corresponding downward sliding movement of the guide structure  20 , a corresponding guided nesting compression of the skirt spring  18 , a corresponding sliding movement of the inner piston wall  44  of the skirt spring  18  relative to the upper end  34  of the piston valve  16  to open the outlet valve and lastly a corresponding downward sliding movement of the piston valve  16  to force material within the flow conduit  30  to flow out through the outlet valve, through the outlet orifice  52  of the guide structure  20  and finally out through the dispensing orifice  58  of the pump actuator  22 . 
     Upon the subsequent release of the pump actuator  22 , the skirt spring  18  expands (return stroke) causing a forcible upward movement of the guide structure  20  and pump actuator  22 , a corresponding sliding movement of the inner piston wall  44  of the skirt spring  18  relative to the upper end  34  of the piston valve  16  to close the outlet valve, and a corresponding upward sliding movement of the piston valve  16 , which in turn creates a vacuum pressure within the flow conduit  30  drawing the inlet valve  14  upwardly from its normally closed position to its open position and drawing material into the flow conduit  30  through the inlet orifice  28 . 
     When the skirt spring  18  returns to its fully expanded position, the flow conduit  30  is re-filled with material and vacuum pressure is reduced allowing the inlet valve  14  to return to its normally closed position. 
     It can therefore be seen that the exemplary embodiment may provide a unique dispensing pump which can be entirely constructed from plastic molded parts and thus easily recycled. 
     While there is shown and described herein certain specific structures embodying various embodiments of the invention, it will be manifest to those skilled in the art that various modifications and rearrangements of the parts may be made without departing from the spirit and scope of the underlying inventive concept and that the same is not limited to the particular forms herein shown and described except insofar as indicated by the scope of the appended claims.