Abstract:
Pre-compression valve systems for trigger sprayers include one-piece valve systems having both check and pre-compression valves or multiple component valve systems.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of, and priority to, U.S. Provisional Application No. 61/471,308, entitled “PRE-COMPRESSION VALVE SYSTEM IN AN ALL PLASTIC DISPENSER WITH A LOCKING PRE-LOAD, UTILIZING A GASKET RETENTION DESIGN AND A TAB PRE-LOADED SPRING,” filed Apr. 4, 2011, and incorporates the same herein by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    Embodiments of the present invention relate to trigger sprayers and in particular to pre-compression type trigger sprayers. 
         [0004]    2. State of the Art 
         [0005]    Trigger sprayers and their uses are well known. In some instances, it is desirable to prevent discharge of a trigger sprayer until a certain pressure—or pre-compression—has been applied to the fluid to be discharged by a trigger sprayer. Various systems have been developed to accomplish such pre-compression features. However, it is desirable to develop new pre-compression configurations which may be easier or more cost efficient to produce and manufacture. 
       BRIEF SUMMARY OF THE INVENTION 
       [0006]    According to certain embodiments of the invention, a pre-compression trigger sprayer may be made of all plastic materials and can be manufactured to dispense in a large range of outputs in spray, stream or foam dispensing patterns. This design can be used to dispense many liquid products from air fresheners, window cleaners, household chemicals, lawn and garden products, automotive products, or other products. 
         [0007]    In some embodiments of the invention, a trigger sprayer is of the type wherein structure is provided for preventing pressurizes liquid from being expelled from an outlet orifice in a nozzle of a trigger sprayer until a predetermined pressure of the liquid is reached in a pumping cylinder and the ejection of liquid in a spray, stream or a foam is stopped or cut off when the pressure of the liquid being pumped by the trigger sprayer in the pumping cylinder falls below a predetermined pressure. 
         [0008]    In still further embodiments, a trigger sprayer may include a pre-compression valve system located in a vertical cylinder behind the horizontal pumping cylinder of a trigger sprayer. 
         [0009]    In further embodiments, a tab on a plastic return spring may be included for increasing the load against the arms of the spring and a locking system may be incorporated that provides a constant pre-load on the pre-compression valve system. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    While the specification concludes with claims particularly pointing out and distinctly claiming particular embodiments of the present invention, various embodiments of the invention can be more readily understood and appreciated by one of ordinary skill in the art from the following descriptions of various embodiments of the invention when read in conjunction with the accompanying drawings in which: 
           [0011]      FIG. 1  illustrates a cross-sectional view of a trigger sprayer according to embodiments of the present invention; 
           [0012]      FIG. 2  illustrates an enlarged cross-sectional view of a pre-compression system according to various embodiments of the invention; 
           [0013]      FIG. 3  illustrates an enlarged cross-sectional view of a pre-compression system according to various embodiments of the invention; 
           [0014]      FIG. 4  illustrates an enlarged cross-sectional view of a pre-compression system according to various embodiments of the invention; 
           [0015]      FIG. 5  illustrates an enlarged cross-sectional view of a pre-compression system according to various embodiments of the invention; 
           [0016]      FIG. 6  illustrates an enlarged cross-sectional view of a pre-compression system according to various embodiments of the invention; 
           [0017]      FIG. 7  illustrates a gasket for a trigger sprayer according to embodiments of the invention; 
           [0018]      FIG. 7A  illustrates a gasket assembly with a trigger sprayer according to embodiments of the invention; 
           [0019]      FIG. 8  illustrates a cross-sectional view of a spring assembled with a trigger sprayer according to various embodiments of the invention; 
           [0020]      FIG. 8A  illustrates a spring according to various embodiments of the invention; 
           [0021]      FIG. 9  illustrates an exploded view of the components illustrated in  FIG. 4 ; 
           [0022]      FIG. 10  illustrates an exploded view of the components illustrated in  FIG. 2 ; and 
           [0023]      FIG. 11  illustrates an exploded view of the components illustrated in  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]    According to various embodiments of the invention, a pre-compression trigger sprayer may include any configuration as shown in  FIGS. 1  thru  11 . A pre-compression trigger sprayer according to various embodiments may include an open and closed opposing valve system where the pre-compression valve  1  is located in a vertical cylinder  2 , or fluid flow path, behind the horizontal pumping cylinder  3 , or piston chamber. Located below the pre-compression valve  1  is a check valve  4 . The check valve  4  can be part of the pre-compression valve system shown in  FIG. 2  as a disc type valve  4  or as in  FIG. 3  as a frusta-conical shaped valve  5  or as in  FIG. 4  as a separate valve  14  or many other configurations that would serve as a one way check valve system preventing liquid under pressure or at rest returning back into the container from which it was once drawn when a vacuum was created inside of the pumping cylinder  3 . 
         [0025]    A pre-compression valve  1 , as shown in  FIG. 1 , can have a flat, concave or convex shape.  FIG. 1  shows a valve  1  in a trigger sprayer however this valve system could be used in any opposing valve dispenser. The pre-compression valve system shown in  FIG. 1  requires a predetermined pressure to allow liquid to pass between valve  1  and the valve seat  7 . This occurs when a vacuum is created in the pumping cylinder  3  by the movement of the piston to the front portion of the pumping cylinder which has been forced back by a spring biasing component  8 . The vacuum draws the liquid up the dip tube  9  from the container and passes the check valve  4  into the pumping cylinder  3 . Then, once the piston is moved to the back portion of the pumping cylinder  3  the liquid that was drawn into the pumping cylinder  3  is compressed and forces the liquid in area  10  to compress the top portion of pre-compression valve  1  allowing liquid to travel past the pre-compression valve  1  and valve seat  7  of component  11  into the flow channel  12  then exit the nozzle swirl orifice as a spray, foam or accelerated stream. 
         [0026]    In some embodiments, a one piece pre-compression valve system as shown in  FIG. 1  may include a priming valve portion  1  and the check valve portion  4  molded from flexible plastic materials which may allow the valve portions of the system to move freely under pressure or vacuum. This is not however desirable for the non-valve area  15  of the structure. Movement of the non-valve area  15  can reduced the overall effectiveness of the pre-compression valve system. Embodiments of the present invention may overcome this problem by inserting post  13  of valve case  16  which is made of a harder material inside of the pre-compression valve system. Inserting the harder material valve case post  13  into non-valve area  15  may also eliminate the requirement to mold the pre-compression valve system component in two different materials, thus reducing the manufacturing cost. Channel  17  inside post  13  of the valve case  16  may also serve as conduit to allow normal atmosphere outside air pressure to enter behind the pre-compression valve  1  allowing the pre-compression valve  1  to move freely without concern of a vacuum or compressed trapped air on the opposite side of the pre-compression valve  1 . 
         [0027]    The pre-compression valve system shown in  FIG. 5  is an optional design for the valve seat  18 . In this embodiment, the priming valve  19  which is part of the lower check valve  20 , or which could be made of a separate component, does not move. Instead the valve seat  18  moves upward against a bias spring element  21 . This movement does not occur until a predetermined pressure of the liquid is reached in the pumping cylinder  3  as described before. The moving valve seat  18  embodiment may require a sealing means  35  between the moving valve seat  18  and the inside diameter of flow channel  12 . This design may also be reversed where the valve portion replaces the valve seat  18  and is part of the upper bias spring element  21  and moves upwards and the valve seat portion replaces the priming valve  19  and is part of the lower check valve  20  and does not move. 
         [0028]      FIG. 6  illustrates another embodiment which may include a cost reduction option which eliminates the separate valve seat component  11  shown in the pre-compression valve system of  FIG. 1 . In this embodiment the valve seat  36  may be part of the housing  25 . The pre-compression valve system shown in  FIG. 6  functions the same as the pre-compression valve system shown in  FIGS. 1 ,  2 ,  3  and  4 . 
         [0029]    The positive lock pre-compression valve pre-load design shown in  FIG. 7  provides a constant load between surface  23  of valve case  16  and surface  24  of housing  25  preventing movement of pre-compression valve system which is assembled into valve case  16  and housing  25 . Undercuts  29  on housing  25  are snapped through slots  30  in valve case  16  under a preload interference. Movement of the pre-compression valve system may result in inconsistency of stokes to prime, of liquid volume output, and of the spray/foam/stream patterns produced from the dispensing system. 
         [0030]    A positive lock gasket retention system for a closure is shown in  FIGS. 7 and 7A . Gasket  26  may be retained in place through slots  31  in gasket  26  with ribs  21  and undercuts  28  of valve case  16 . 
         [0031]    A bias loaded assist tab  33  on the plastic spring component  8  according to various embodiments of the invention, is shown in  FIG. 8  and provides pressure against the housing surface  34  to assist the spring arms  22  of the plastic spring component  8  on the return vacuum stroke of the piston/actuator creating a vacuum in the pumping cylinder  3  which allows product to be drawn into the pumping cylinder  3 . This process may be repeated over and over which puts stress on the plastic spring arms  22  of the plastic spring component  8  which can break or lose the ability to fully return the piston on the return vacuum stroke. Inclusion of a tab  33  according to embodiments of the invention, increases the strength of the overall plastic spring component  8  thus reducing the stress on the arms  22 . 
         [0032]    Having thus described certain particular embodiments of the invention, it is understood that the invention defined by the appended claims is not to be limited by particular details set forth in the above description, as many apparent variations thereof are contemplated. Rather, the invention is limited only be the appended claims, which include within their scope all equivalent devices or methods which operate according to the principles of the invention as described.