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 rack that is capable of rotational and translational motion within the slot. The rack has a set of gear teeth that engage with a catch on a plunger. The piston moves in the axial direction to force the pre-whipped topping or icing through the outlet in its packaging. The catch on the piston is locked in one direction and pivots in the opposite direction such that the rack engages with the piston when it moves in a first direction and the rack disengages with the piston when it is moved in a second direction opposite the first direction.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims benefit of U.S. provisional patent application Ser. No. 60/704,521 entitled “Dispensing Device” filed on Aug. 1, 2005, and incorporated herein by reference. 
    
    
     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 rack. The rack has a set of gear teeth that engage with a catch on a plunger. The piston moves in the axial direction to force the pre-whipped topping or icing through the outlet in its packaging. The catch on the piston is locked in one direction and pivots in the opposite direction such that the rack engages with the piston when it moves in a first direction and the rack disengages with the piston when it is moved in a second direction opposite the first direction. 
     Rotation of the rack inside the slot moves the gear teeth to the opposite side of the slot from the catch thereby allowing the piston to be pushed back toward the end of the housing for reloading the device. In one embodiment of the invention, closing of the cover automatically causes the rack to rotate back into a position where it can engage with the rack. 
    
    
     
       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 a right side elevational view thereof; 
         FIG. 3  is a left side elevational view thereof; 
         FIG. 4  is a front elevational view thereof; 
         FIG. 5  is a rear elevational view thereof; 
         FIG. 6  is a cutaway perspective view with the cover removed for clarity; 
         FIG. 7  is an enlarged perspective view of a portion of the dispensing device of the present invention; 
         FIG. 8  is a cross-sectional view taken along lines  8 - 8  of  FIG. 6 ; 
         FIG. 9  is a cross-sectional view taken along lines  9 - 9  of  FIG. 8 ; 
         FIG. 10  is an enlarged perspective view of a portion of the dispensing device of the present invention; 
         FIG. 11  is a cross-sectional view of a portion of the device showing the piston disengaged from the rack; 
         FIG. 12  is a perspective exploded view showing flexible packaging containing a supply of a pre-whipped topping; 
         FIG. 13  is a perspective view of the dispensing device of the present invention with the packaging for the topping loaded in the dispenser; 
         FIG. 14  is an enlarged perspective view of the channel in the side wall containing the rack; 
         FIG. 15  is an enlarged view of the trigger mechanism of the dispensing device with the cover removed for clarity; 
         FIG. 16  is a cross-sectional view taken along lines  16 - 16  of  FIG. 15 ; 
         FIG. 17  is a cross-sectional view taken along lines  17 - 17  of  FIG. 15 ; 
         FIG. 18  is a view similar to  FIG. 15 , with the trigger mechanism in a different position; 
         FIG. 19  is a cross-sectional view taken along lines  19 - 19  of  FIG. 18 ; 
         FIG. 20  is a detailed view of the piston and rack showing the movement of the piston when engaged with the rack; and 
         FIG. 21  is a detailed view of the piston and rack showing the catch pivoting away from the rack. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 1-21  generally and initially to  FIGS. 1-5 , a housing  13  has a first end  16  and a second end  19 . The first end  16  is the dispensing end of the unit  10 , and as will be described in greater detail below, the first end  16  may be provided with a pivoting cover  22  having an opening  25  therein. The opening  25  is sized to receive a outlet  28  ( FIG. 12 ) operatively associated with flexible packaging  31  ( FIG. 12 ) containing the product to be dispensed. As will be evident to those of ordinary skill in the art based on this disclosure, the outlet  28  of the packaging  31  may be provided with a dispensing tip (not shown) that is disposed inside the packaging  31  and that moves to the end of the outlet  28  to provide a passageway for the extrudable product once the dispensing begins. The cover  22  is substantially flat such that the unit is capable of being supported on a level surface from the first end  16 . 
     The second end  19  may be provided with a substantially flat end wall  34  such that the unit may also be supported on a level surface from the second end  19 . The second end  19  may also be provided with a hook  23  for hanging the unit  10  from the second end  19  for storage. The hook  23  may be relatively thin and pivotally attached at the second end  19  such that it can be folded against the end wall  34  and will not interfere when the unit  10  is supported by the second end  19 . 
     Turning to  FIG. 6 , the housing  13  defines a cavity  37  that receives the flexible packaging  31  ( FIG. 12 ). The housing  13  may be substantially cylindrical in overall shape such that it is capable of receiving a disk-like piston  40  therein. The piston  40  is capable of sliding inside the housing  13  and is supported around its edges by the inside walls  43  of the housing  13 . The piston  40  and the inner walls  43  are designed with materials and clearances so that the piston  40  slides smoothly inside the housing  13  without losing alignment or binding against the inner walls  43 . The force of the piston  40  against the packaging  31  causes the product to be dispensed through outlet  28  ( FIG. 13 ) at the first end  16 . The housing  13  may be constructed with inner walls  43  and an outer wall  44 . A space between the walls  43 ,  44  can be formed and filled with materials having insulating properties for keeping materials to be dispensed either warm or cold. As an alternative the housing  13  may be formed from a solid walled cylinder constructed of a material having insulating properties. The piston  40  and lid  22  may also be formed from materials having insulating properties. 
     For a cylindrical housing  13 , the piston  40  is round and may be provided with a thickness wide enough to provide for stable sliding against the inside walls  43 . The piston  40  is provided with a catch  46  (FIGS.  8 , 9 ) that is capable of engaging with a gear rack  49  that is disposed inside the housing  13 . The movement of the gear rack  49 , which is described in greater detail below, causes the piston  40  to move in the axial direction with respect to the housing  13 . Movement of the piston  40  in the axial direction causes the flexible packaging  31  to be compressed and the product is forced out as described above. 
     The gear rack  49  may be mounted on the housing  13  in a slot  52  formed by a tube-like member  54  ( FIG. 8 ) that is attached to the housing  13  at its periphery. The slot  52  could also be integrally formed in a recess in the housing  13  itself. The slot  52  extends in the axial direction from the first end  16  to the second end  19 , and the slot  52  extends in the axial direction adjacent to the inner wall  43  of the housing  13 . The tube-like member  54  forming the slot  52  may be cylindrical or other suitable shape. The inside wall  43  of the housing  13  is substantially circular in cross-section except for a gap  55  where the slot  52  is formed by the tube-like member  54 . The piston  40  slides inside the housing  13  against the inner walls  43 , and the catch  46  extends into the slot  52  where it engages with the rack  49 . The rack  49  moves back and forth inside the slot  52  as will be described in greater detail below. The dispenser  10  may be provided with a single rack  49  as shown in this example. Additional racks  49  may also be used. The reciprocating rack  49  eliminates the need for a connecting rod attached to the piston  40  and therefore reduces the space required by the unit  10 . 
     As shown in  FIG. 7 , the gear rack  49  is formed by a rod  57  having a set of gear teeth  60  disposed on at least a portion of the periphery of the rod  57 . In the example shown, the rod  57  is elongate and formed from a hollow cylindrical body. Other shapes may also be suitable. The rod  57  extends in the direction of the longitudinal axis of the unit  10  and may be supported from one or both ends. The rod  57  is hollow and slides over a guide pin  61 . The guide pin  61  may be formed from a solid rod-like member attached at the first end  16 . The guide pin  61  fits inside the rod  57  and extends for a portion of the length of the housing  13 . The rod  57  slidingly engages with the pin  61  to maintain alignment of the gear rack  49  in the slot  52 . 
     Turning to  FIG. 9 , the catch  46  on the piston  40  extends into the slot  52  and engages with the teeth  60  on rod  57 . The catch  46  is pivotally attached to the piston  40  at pivot point  47  such that it is capable of pivoting away from the gear teeth  60  when the rack  49  moves in a particular direction. Accordingly, as best shown in  FIGS. 20 and 21 , when the gear teeth  60  travel in a first direction indicated by arrow  61 , the catch  46  engages with the teeth  60  and the piston  40  moves in unison with the gear rack  49  in the first direction. When the gear rack  49  is moved in a second direction (indicated by arrow  62 ) opposite the first direction, the catch  46  pivots away from the gear teeth  60  and the gear rack  49  is capable of sliding past the piston  40  without moving the piston  40 . Accordingly, during normal operation the piston  40  moves in one direction toward the dispensing end  16 . Between each actuation of the trigger  63 , the piston  40  is held in position by engagement of the catch  46  with teeth  60  in the rack  49 . The catch  46  is arranged such that it is stopped in one direction because of engagement with a shoulder  51  ( FIG. 21 ). Accordingly, movement of the rack  49  from left to right with respect to the figures causes the piston  40  to move and the piston  40  cannot be moved to the left with respect to the rack  49  because of the engagement of the catch  46  with the teeth  60 . 
     The unit  10  is designed such that the piston  40  moves from the second end  19  toward the first end  16  where product is dispensed through opening  25 . The gear rack  49  moves in reciprocating translatory fashion toward and away from the first end  16 . 
     The unit  10  may be operated with one hand by means of an actuating trigger  63  ( FIG. 2 ) that is mechanically coupled to the gear rack  49  such that rotation caused by squeezing of the trigger  63  toward a stationary handle  72  causes the gear rack  49  to move towards the first end  16  of the unit  10 . In the example shown, the actuating trigger  63  is coupled to an axle  66  which rotates a link  69  to convert the rotary motion of the axle  66  into linear motion of the gear rack  49 . The link  69  is connected to the rack  49  by means of element  68  which travels in slot  67  and imparts a force against a collar  70 . In  FIG. 15  the trigger  63  is shown in its normal position prior to actuation. As shown in  FIG. 18 , squeezing the trigger  63  causes it to rotate toward stationary handle  72  as indicated by arrow  71 . The collar  70  is disposed around the outside of the rack  49 . A bearing  71  (not shown) inside the collar  70  enables the rack  49  and guide pin  61  to rotate relative to the collar  70 . The collar  70  and the rack  49  are connected such that movement of the collar  70  in the axial direction caused by the link  69  causes the rack  49  to move in unison with the collar  70  in the axial direction. The link  69  moves the rack  49  back and forth in the direction of the longitudinal axis of the unit  10 . 
     The actuating trigger  63  is squeezed toward a stationary handle  72  in order to move the gear rack  49  in the first direction toward the first end  16  of the housing. 
     When the actuating handle  63  is released, the axle  66  rotates in the opposite direction by means of a biasing member such as a coil spring  75 . This rotation causes the link  69  to move in the opposite direction thereby moving the gear rack  49  in the second direction. 
     Returning to  FIG. 9 , during the normal operation of the unit  10 , the piston  40  moves toward the first end  16  where the product is dispensed through the nozzle  28  ( FIG. 12 ). With each pull of the actuating trigger  63 , the piston  40  advances a predetermined distance which can be adjusted as described above. As discussed above, when engaged with the gear rack  49 , the piston  40  can only move in a single direction. After the piston  40  reaches the first end  16  and all of the product is dispensed, the empty package must be removed and the piston  40  must be returned to the second end  19  of the unit  10  for refilling. In order to move the piston  40  relative to the rack  49  in the second direction, the gear rack  49  must be disengaged from the catch  46  on the piston  40 . In the example shown, the gear teeth  60  are disposed on one side of the cylindrical rod  57 . Accordingly, rotation of the rod  57  (as indicated by arrow  58  in  FIG. 11 ) will cause the teeth  60  to rotate out of engagement with the catch  46 . Once the teeth  60  are rotated away from the catch  46 , the piston  40  can be manually pushed in the direction of arrow  59  toward the second end  19  of the housing  13  for refilling the unit  10 . 
     Turning to  FIG. 10 , one example for automatically rotating the teeth  60  away from the catch  46  is shown. The cover  22  is pivotally attached to the housing  13  at the first end  16 , and rotating the cover  22  to open the unit  10  causes the gear rack  49  to rotate. The cover  22  is pivotally mounted on an axle  91  that is supported from the outside of the housing  13  adjacent to the first end  16 . The axle  91  also has a first gear  94  mounted thereon that rotates in the same direction as the cover  22  and axle  91 . The gear  94  engages with a transverse gear  97  that is mounted at an approximately ninety degree angle to the first gear  94 . Accordingly, the turning of gear  94  causes rotation of gear  97  in a perpendicular plane. The transverse gear  97  is mechanically coupled to the guide pin  61  by means of a third gear  100 . Accordingly, the rotation of the cover  22  from a closed to an open position causes the guide pin  61  to rotate the rack  49  by means of a set of gears  94 ,  97 ,  100 . The rack  49  rotates from a position where the teeth  60  engage with the catch  46  to a position (best shown in  FIG. 11 ) where the teeth  60  are disengaged and clear from the catch  46  thus allowing the piston  40  to slide freely in the second direction (indicated by arrow  59  in  FIG. 11 ) toward the second end  19  of the housing  13 . 
     The guide pin  61  has a protuberance  103  disposed thereon and extending outward. A longitudinal slot  106  formed in the gear rack  49  receives the guide pin  61 . The protuberance  103  mechanically couples the guide pin  61  to the rack  49  with regard to rotation. Accordingly, rotation of the guide pin  61  by operation of the gears  94 ,  97 , and  100  causes the rack  49  to rotate in unison by means of the protuberance  103  engaging with the side wall of the rack  49  adjacent to the slot  106 . 
     In contrast, the longitudinal slot  106  allows the protuberance  103  to freely slide back and forth in the axial direction such that the rack  49  is capable of sliding relative to the guide pin  61  in the axial direction. As a result, the guide pin  61  and rack  49  rotate in unison but are capable of sliding relative to each other in the axial direction. 
     Turning to  FIGS. 12-14 , in order to fill the unit  10  the cover  22  is opened which causes the rack  49  to rotate away from the catch  46  on the piston  40 . The piston  40  can then be pushed to the back of the housing  13 . The flexible packaging  31  containing the material to be dispensed is inserted into the housing  13  and the outlet  28  is threaded through the opening  25  in the cover  22 . The flexible packaging  31  may be provided with an extended portion  32  at the end opposite the outlet. The extended portion  32  provides a surface for abutting the piston  40  to provide additional stability. The cover  22  is then closed as shown in  FIG. 13  and the outlet  28  is opened by means of scissors, a knife, or the like. Alternatively, the outlet  28  may be provided with a tear away feature. Once the outlet  28  is opened, material may be dispensed by squeezing the trigger  63  toward stationary handle  72 . 
     A pivoting catch  109  may be provided adjacent the first end  16  of the housing  13  to hold the cover  22  in the closed position. The catch  109  may pivotally attached at the first end  16  such that depressing a lever  112  disposed on the opposite side of a pivot point  115  causes the catch  109  to rotate away from engagement with the cover  22 . The catch  109  may be spring biased in the closed position as shown. 
     The unit  10  has been described in connection with a mechanical drive system for the reciprocating rack  49 . It will be evident to those of ordinary skill in the art based on this disclosure that the linkage for the gear rack  49  could be driven by an electric motor or the like. 
     The present invention has been described in connection with a dispenser suitable for use with pre-whipped toppings or icings in the food industry. However, it is to be understood that the present invention may be used in any industry where viscous materials need to be dispensed with a hand held tool. 
     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.