Abstract:
A dispensing device having a housing capable of receiving a pre-packaged charge of pre-whipped topping or icing. The housing has an inner wall with a slot formed therein for receiving a rod. The rod engages with a pawl mechanism to move a piston in the axial direction to force the pre-whipped topping or icing through the outlet in its packaging. The pawl engages with the rod when it moves in a first direction and the pawl disengages with the rod when it is moved in a second direction opposite the first direction.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part and claims benefit of U.S. patent application Ser. No. 11/388,592 entitled “Dispensing Device” filed on Mar. 24, 2006, which claims benefit of U.S. Provisional Patent Application No. 60/704,521 entitled “Dispensing Device” filed on Aug. 1,  2005 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention may be used for dispensing viscous materials such as paste-like extrudable materials, extrudable foams, or the like. One area where the invention has particular application is the food industry. In the food industry, icing or pre-whipped toppings are typically applied manually by means of a cone shaped flexible package containing the substance to be dispensed. As an example, pre-whipped topping is typically supplied in a sealed bag having a conical shape with the product being dispensed from the narrower end where an outlet portion is formed. The outlet portion is typically opened by cutting with a pair of scissors. Other methods for opening the bag are also suitable. Once the flexible packaging is opened at the outlet, the product is dispensed by squeezing the sides of the packaging to force the product to exit through the opening. Manual dispensing of the pre-whipped topping or icing in this manner can cause muscle fatigue in the workers which can negatively impact productivity. 
     There is a need for a dispensing device that is easier to operate, that can be operated with one hand, that can be stored in a limited space, and that provides cooling properties for maintaining a safe temperature for the topping. In order to maintain the physical characteristics of the dispensed product, the dispenser should not provide any force to the pre-whipped topping or icing when the unit is not dispensing. 
     SUMMARY OF THE INVENTION 
     The present invention meets the above-described need by providing a dispensing device having a housing capable of receiving a pre-packaged charge of pre-whipped topping or icing. The housing has an inner wall with a slot formed therein for receiving a rod. The rod engages with a pawl mechanism to move a piston in the axial direction to force the pre-whipped topping or icing through the outlet in its packaging. The pawl engages with the rod when it moves in a first direction and the pawl disengages with the rod when it is moved in a second direction opposite the first direction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is illustrated in the drawings in which like reference characters designate the same or similar parts throughout the figures of which: 
         FIG. 1  is a perspective view of the dispensing device of the present invention; 
         FIG. 2  is an exploded perspective view of the dispensing device of the present invention; 
         FIG. 3  is an end elevational view of the dispensing device; 
         FIG. 4  is an end elevational view of the dispensing device; 
         FIG. 5  is a cross-sectional view taken along lines  5 - 5  of  FIG. 3 ; 
         FIG. 6  is a cross-sectional view taken along lines  6 - 6  of  FIG. 4 ; 
         FIG. 7  is a schematic diagram showing the operation of the pawl mechanism of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring initially to  FIG. 1 , the dispensing device  10  of the present invention includes a body  13  having a first portion  16  with a round profile and a first diameter  19 . The body  13  has a second portion  22  with a smaller diameter. The first portion  16  extends to a base portion  25  having a larger diameter. Although, the embodiment of the dispensing device  10  is described in connection with a round profile other shapes may be suitable as will be evident to those of ordinary skill in the art based on this disclosure. The body  13  may be provided with a hook  28  for hanging the device  10  when not in use. 
     The device  10  includes a cover  31  that may be removably attached to the front of the body  13 . As shown the cover  31  may be provided with an opening  32  that frictionally engages with a protrusion  34  extending from the outside of the body  13 . A tab  35  may be provided for removing the cover  31 . The cover  31  has an outlet opening  37  at its center where a tip cover  40  is provided to cover the outlet opening  37  when the device  10  is not in use. 
     A handle  43  may be provided with a trigger  46  that is attached at pivot point  49 . The trigger  46  is biased by a spring  52  ( FIG. 2 ) in the open position. The trigger  46  operates a reciprocating rod that drives a piston as will be described in greater detail below. 
     Turning to  FIG. 2 , the device  10  may receive a cylindrical shaped flexible package  55  with a built-in dispensing tip  58 . The construction of the built-in dispensing tip  58  will be evident to those of ordinary skill in the art and therefore will not be discussed in detail herein. A piston  61  provides the force for causing a viscous material such as a pre-whipped topping to exit from the package  55 . The piston  61  is mechanically coupled to a reciprocating rod  64 . The rod  64  is moved back and forth in the axial direction indicated by arrow  67  by means of the spring biased trigger  46 . 
     The rod  64  is coupled to the piston  61  by means of a pawl mechanism. The piston  61  has an extended portion  68  with an opening  70  that receives the rod  64  therethrough. A pawl  73  is biased by a spring  76  in an angled position relative to the piston  61  (best shown in  FIG. 7 ). When the rod  64  moves from right to left with respect to the orientation of  FIGS. 2 and 7 , the frictional engagement between the rod  64  and the opening  79  in the pawl  73  causes the piston  61  to move forward in unison with the rod  64 . The movement of the rod  64  caused by squeezing the trigger  46  causes the piston  61  to move from right to left with respect to the figure. This movement of the piston  61  compresses the flexible packaging  55  causing product to exit through the outlet opening  37 . When the trigger  46  is released and the rod  64  moves in the opposite direction (from left to right with respect to the figure), the piston  61  moves from left to right slightly and decouples from the rod  64 . As the rod  64  moves from left to right, the pawl  73  pivots away from the piston  61 , and the rod  64  slides through the opening  79  in the pawl  73  into its spring-biased default position. The piston  61  remains roughly in the same position until the trigger  46  is squeezed again. 
     When the flexible packaging  55  is empty and the piston  61  needs to be moved from left to right in order to load another package of material, a reset rod  80  (best shown in  FIG. 7 ) can be used. The reset rod  80  passes through the piston  61  and engages with the pawl  73  to cause it to pivot away from the piston  61  to allow the piston  61  to slide easily over the rod  64  back to its retracted position. 
     Turning to  FIGS. 3 and 4 , an end view of the device  10  shows the handle  43  and trigger  46 . The dispensing tip  58  is shown at the center of the figure and the tabs  35  for opening the cover  31  are also shown. 
       FIG. 5  shows the dispensing device  10  with the piston  61  advanced to the end of its travel and the built in tip  58  of the packaging  55  seated in the outlet of the device  10 . The trigger  46  has been released and the pawl  73  is in the position where the rod  64  can slide from left to right without moving the piston  61 . After dispensing is completed, the cover  31  is removed and the pawl  73  is pivoted away from the piston  61  so that the piston  61  can be pushed back to the opposite end of the device  10  for loading a new package  55 . 
       FIG. 6  shows the dispensing device  10  in a half full condition with the trigger  46  depressed during dispensing. 
     Turning to  FIG. 7 , a schematic diagram shows the piston  61  with the pawl  73  biased by spring  76  at an angle. When the rod  64  is moved from right to left in the direction of arrow  88 , the frictional force of the rod  64  on the pawl  73  causes the piston  61  to move. When the rod  64  moves from left to right, the friction causes the pawl  73  to pivot away from the piston  61  to a position where the rod  64  can overcome the friction caused by engagement with the edge of the pawl  73  around opening  79 . In this position, the rod  64  slides freely through the opening  79  in the pawl  73  and the rod  64  decouples from the piston  61 . 
     In order to move the piston  61  from left to right to reload the dispensing device  10 , a reset rod  80  may be used to press against the pawl  73  to cause it to pivot into the perpendicular position so that the piston  61  can slide along the rod  64  from left to right in the direction of arrow  90  with respect to the orientation of the figure. 
     While the invention has been described in connection with certain embodiments, it is not intended to limit the scope of the invention to the particular forms set forth, but, on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.