Patent Publication Number: US-6659309-B2

Title: Portion control dispenser

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims benefit of and co-owned U.S. Provisional Patent Application Ser. No. 60/338,776 entitled “Portion Control Pump”, filed in the U.S. Patent and Trademark Office on Dec. 5, 2001, by the inventor herein, the specification of which is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention disclosed herein relates generally to dispensing systems, and more particularly to a dispensing system for dispensing portions of a product in a tightly controlled manner which minimizes waste caused by residual product left undispensed in a container. 
     2. Background of the Prior Art 
     A wide variety of viscous fluids, including personal care products (e.g., tooth paste, shaving cream, cosmetics, and shampoo), food products (e.g., condiments, salad dressings, and the like), as well as industrial products (e.g., cleaning fluids, lubricating oils and greases) are provided in flexible containers, such as sealed plastic bags and light collapsible tubes. Even health care products, such as blood and medications, may be stored in and dispensed from a flexible or collapsible bag. 
     When such products are provided in bulk, it is impractical to squeeze the container by hand in order to discharge the required quantity of its contents. Numerous devices provided in the prior art have been employed to dispense the contents of such flexible containers. Many such devices mechanically squeeze the container to extrude the contents out through a dispensing outlet. Generally, such devices have provided mechanical means such as springs or ratchets to assist in extruding the fluid from a flexible or collapsible bag. Other dispensers have typically provided arrangement of a container so that the fluid may flow from the container under the influence of gravity. In the case of blood transfusions, dispensing of fluid is typically regulated by a valve whose flow rate depends upon the amount of time desired to empty the container. For example, U.S. Pat. No. 4,850,971 to Colvin discloses an infusion pump having a linear roller driven by constant force springs to extrude blood from a flexible container by rolling an end of the container on the linear roller so as to direct the fluid toward the dispensing end of the container. Flow is regulated through use of needles of varying size on the dispensing line. 
     U.S. Pat. No. 4,044,764 to Szabo et al. discloses a fluid infusion apparatus having a spring motor which pulls a flexible container through a pair of rollers so as to direct fluid in the container towards the dispensing end of the container. A speed control clock motor engages a portion of the carriage carrying the container so as to resist the pull of the spring motor and provide timing control for dispensing of fluid from the container. 
     U.S. Pat. No. 3,151,616 to Selfon discloses a transfusion apparatus in which a flexible bag containing blood, plasma, or the like is progressively flattened as a pair of rack-gear-mounted rollers travels over the bag, directing its contents towards the dispensing end of the apparatus. 
     For other products, the portion of product dispensed is typically regulated by limiting the amount by which the container is compressed. For example, U.S. Pat. No. 3,738,533 to Bertrand discloses a motorized collapsible tube dispenser in which a pair of motor-driven rollers are driven downwards over a vertically suspended tube so as to direct the contents of the tube towards the dispensing end. 
     U.S. Pat. No. 6,089,405 to Schmitt discloses a manually operable dispenser for a tube containing cream or paste (e.g., toothpaste) having a housing with an opening at its base for receiving the dispensing end of the tube, and a pair of rollers which are translated up and down in the base so as to direct material within the tube toward the dispensing end. 
     While these dispensers have been generally satisfactory for their intended uses, there has been found to remain a need for an apparatus to control the dispensing of fluid products from such flexible containers in order to facilitate the dispensing of fluid products in a simple and effective manner while minimizing waste of product. 
     SUMMARY OF THE INVENTION 
     The present invention provides a dispenser for fluid products stored in a flexible container, in which operation of a dispensing pump enables an extrusion assembly to squeeze the flexible container, thus continuously directing all remaining product in the container towards the dispensing end. The dispensing pump preferably removes product from the container by positive displacement action, and more preferably by peristaltic action. A preferred embodiment of the apparatus of the invention comprises a frame with an upwardly spring biased carriage configured to removably hold a flexible container that holds product to be dispensed. An extrusion assembly preferably in the form of one or more rollers is situated at the top of the frame and is positioned such that the carriage will pull the flexible container upward past such one or more rollers as product is dispensed from the container. 
     The portion control dispenser described herein thus enables dispensing portions of a product in a tightly controlled manner, which in turn minimizes waste caused by residual product left undispensed in a container. A frame preferably provides support for a flexible container, and includes a moveable carriage having a drive assembly, a guide assembly, and a flexible bag mount, preferably in the form of a traction bar assembly. The frame also supports an extrusion assembly, preferably in the form of one or more rollers, for directing product towards the dispensing end of the container, and a dispensing pump for dispensing a controlled portion of product from the container. Such construction enables the flexible container to remain completely closed except for its outlet so that the product remains unexposed to the atmosphere until it exits from the dispensing pump. 
     It is generally contemplated that the dispenser can be employed in a variety of settings such as food service stores or institutions, other commercial settings and even for personal use in homes and the like. 
     In other applications, it may be important that the product be prevented from contacting the air or the environment at least until the product is properly dispensed. 
     Regardless of the setting, it is further contemplated that the product be initially stored in a flexible or collapsible container which can then be arranged in a dispenser operable for dispensing the product from the container in a simple and effective manner to assure delivery of a satisfactory amount of the product at a controlled rate of delivery. 
     It is further desirable that the dispenser be capable of dispensing the material only in response to operation by a user of a dispenser device. 
     The various features of novelty that characterize the invention will be pointed out with particularity in the claims of this application. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above and other features, aspects, and advantages of the present invention are considered in more detail, in relation to the following description of embodiments thereof shown in the accompanying drawings, in which: 
     FIG. 1 is a side perspective view of a portion control dispenser according to one preferred embodiment of the instant invention. 
     FIG. 2 is an exploded view of the portion control dispenser of FIG.  1 . 
     FIG. 3 is a perspective view of a press roller assembly of the portion control dispenser of FIG.  1 . 
     FIG. 4 is an exploded view of the press roller assembly of FIG.  3 . 
     FIG. 5 is a perspective view of a drive assembly of the portion control dispenser of FIG. 1 shown in both a fully extended and a fully retracted position. 
     FIG. 6 is an exploded view of the drive assembly of FIG.  5 . 
     FIG. 7 is a perspective view of a guide assembly of the portion control dispenser of FIG.  1 . 
     FIG. 8 is an exploded view of a traction bar assembly of the portion control dispenser of FIG.  1 . 
     FIG. 9 is a front view and side, sectional view of the traction bar assembly of FIG.  8 . 
     FIG. 10 is a rear view and side, sectional view of a movable jaw of the traction bar assembly of FIG.  8 . 
     FIG. 11 is an exploded view of the peristaltic pump assembly of the portion control dispenser of FIG.  1 . 
     FIG. 12 is a front, side, and top view of the peristaltic pump assembly of FIG.  11 . 
     FIG. 13 is a front and side, sectional view of a gear drive assembly of the peristaltic pump assembly of FIG.  11 . 
     FIG. 14 is an exploded view of a pump head assembly of the peristaltic pump assembly of FIG.  11 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The invention summarized above and defined by the enumerated claims may be better understood by referring to the following description, which should be read in conjunction with the accompanying drawings in which like reference numbers are used for like parts. This description of an embodiment, set out below to enable one to build and use an implementation of the invention, is not intended to limit the enumerated claims, but to serve as a particular example thereof. Those skilled in the art should appreciate that they may readily use the conception and specific embodiments disclosed as a basis for modifying or designing other methods and systems for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent assemblies do not depart from the spirit and scope of the invention in its broadest form. 
     As shown in the side, perspective view of FIG. 1, a first embodiment of the portion control dispenser of the instant invention comprises a rigid, upright frame  10  to which a carriage  40  is slidably connected for generally vertical displacement with respect to frame  10 . Carriage  40  is configured to removably mount a flexible container  30  whose contents are to be dispensed. Frame  10  is provided adjacent its upper end with an extrusion assembly  18 . In the particular embodiment depicted in FIG. 1, extrusion assembly  18  comprises arms  11  and  12  which rotatably mount rollers  20  and  21  (FIG. 2) so as to enable carriage  40  to pull container  30  between the rollers during its upward travel. A dispensing pump  100  is preferably mounted to frame  10  and, during operation, is in fluid communication with the interior of container  30  via tubing (not shown) for dispensing the contents of container  30 . Dispensing pump  100  is preferably provided in the form of a positive displacement pump, and more preferably in the form of a peristaltic pump. 
     The portion control dispenser of the instant invention is configured to support a wide array of containers  30  having a generally flexible exterior, including flexible bags, flexible pouches, and aseptic packages commonly used for holding food products. 
     Frame  10  is preferably formed of a rigid material, such as steel or aluminum, and is configured to mount the dispensing assembly in a generally vertical orientation, thus benefiting from the force of gravity which aids in the dispensing process, and providing the smallest possible footprint for such a dispensing apparatus. Frame  10  may be provided feet  14  extending outwardly from the bottom of each wall of frame  10 . As shown in the exploded view of FIG. 2, frame  10  preferably has a slotted front face defining an upper wall portion  13   a  and a lower wall portion  13   b , and a generally horizontal opening defined therebetween. Upper wall portion  13   a  and lower wall portion  13   b  preferably lie within the same plane, and are optionally situated at a slight angle from a vertical plane so as to aid in positioning container  30  within the dispensing apparatus. 
     As mentioned above, carriage assembly  40  is configured to draw container  30  upward through rollers  20  and  21  as product is dispensed from container  30 . As shown in the exploded view of FIG. 2, carriage assembly  40  preferably comprises drive assembly  50 , side guide assemblies  60 , and a mount  70  configured to removably hold an end of a flexible container. In the embodiment of FIG. 1, mount  70  is preferably provided in the form of a traction bar assembly. 
     Referring to FIGS. 3 and 4, extrusion assembly  18  comprises arms  11  and  12  that may be affixed to sidewalls of frame  10  using screws, bolts, or similarly configured fasteners. Rotatably mounted between arms  11  and  12  are exterior roller  20  and interior roller  21 . As shown more particularly in the exploded view of FIG. 4, interior roller  21  is provided a shaft  21   a  (about which roller  21  may freely rotate) which is inserted into boreholes  23  on the interior of each of arms  11  and  12  so as to rotatably mount roller  21  between arms  11  and  12 . Interior roller  21  is oriented to fit generally within the horizontal opening between upper wall portion  13   a  and lower wall portion  13   b  so as to enable unobstructed rotation of interior roller  21 . Spring members  24 , such as coil springs, are held within a socket in the rear wall of each of arms  11  and  12  such that one end of spring members  24  engage top wall portion  13   a  of the front of frame  10 , while the opposite end of spring members  24  engage shaft  21   a.  In this way, interior roller  21   a  is spring biased toward exterior roller  20 . 
     Exterior roller  20  is also provided a shaft  20   a  about which roller  20  may freely rotate, the shaft having a first end  27  and a second end  28 . First end  27  of shaft  20   a  is preferably provided a borehole configured to receive a dowel  25 . Dowel  25  is inserted through the top wall of arm  11  until it passes through the borehole in first end  27 , thus preventing separation of roller  20  from arm  11 , while enabling roller  20  to pivot about dowel  25  away from interior roller  21 . Such pivoting movement enables easy placement of a container  30  into the dispensing apparatus. The second end  28  of shaft  20   a  is inserted into a recess  26  in arm  12 . Extending through the exterior wall of arm  12  and into recess  26  is a plunger  22  provided with a detent mechanism  22   a  at its forward end. Second end  28  of shaft  20   a  is preferably hollow so that it may receive detent mechanism  22   a  therein, thus preventing separation of the second end  28  of shaft  20   a  from arm  12 . However, by pulling actuating knob  22   b  of plunger  22  outward, detent mechanism  22   a  may be withdrawn from the second end  28  of shaft  20   a , thus enabling the release of second end  28  from arm  12  as roller  20  is rotated about dowel  25  at the first end  27 . 
     As shown in FIG. 5, drive assembly  50  is operable to move from a fully extended position when a new container  30  is inserted into the dispensing apparatus, to a fully retracted position in which all product has been dispensed from container  30 . With reference to both FIGS. 5 and 6, drive assembly  50  comprises a damping cylinder  51  having an outwardly extensible rod  51   a  whose movement is restricted by a damping medium, such as oil, air, or any other compressible medium as is well known in the art, within cylinder  51 . The base of cylinder  51  is attached to a bracket  52 , preferably by means of a threaded portion at the base of cylinder  51  and an opening extending through bracket  52  having a matching receiving threaded portion therein. Rod  51   a  extends through bracket  52  and is affixed to a drive beam  53 , preferably through use of a threaded coupler  54  or other connection mechanism as is well known in the art. A pair of motor supports  55  are affixed to bracket  52  on opposite sides of cylinder  51 , such as by screws, bolts, or similarly configured fasteners. Each motor support  55  comprises sidewalls  55   a  and  55   b . A front side of sidewalls  55   a  and  55   b  is provided apertures such that each motor support may be affixed to the back surface of the upper portion  13   a  of the front face of frame  10 . Extending through each sidewall  55   a  and  55   b  is a borehole  55   c , through which a motor shaft  56  is mounted. Rotatably mounted on each motor shaft  56  is a motor drum  57 , each of which motor drum in turn mounts a constant force spring motor  58 . In an unwound configuration, each spring motor  58  biases drive beam  53  towards bracket  52 , thus having a tendency to draw a container  30  mounted to drive assembly  50  upward through rollers  20  and  21 . However, spring motors  58  are selected such that the force to draw a filled container  30  through roller assembly  18  exceeds the force applied from spring motors  58 . Thus, any volume of container  30  containing undispensed material will always rest below rollers  20  and  21 , and only when additional product is dispensed from the bottom of container  30  through dispensing pump  100  will carriage assembly  40  be able to further pull container  30  upward through roller assembly  18 . Of course, as additional material is dispensed from container  30 , and container  30  is thus pulled further upward through roller assembly  18 , any residual material within container  30  is directed by the force of rollers  20  and  21  downwards, thus significantly reducing the amount of wasted material that might be realized by prior art dispensing apparatus. 
     In order that upward movement of drive assembly  50  may result in drawing container  30  through roller assembly  18 , a pair of guide assemblies  60  is affixed to each side of drive beam  53 , which guide assemblies in turn are connected at their upper ends to traction bar assembly  70 . 
     As shown in the perspective view of FIG. 7, each guide assembly  60  preferably comprises a telescoping rail assembly  61  enabling a central panel  61   a  of the rail assembly  61  to extend outward in a direction parallel to the major axis of rail assembly  61 . Telescoping rail assembly  61  is of conventional configuration, the construction and operation of which is well known to those of ordinary skill in the art. Affixed to the bottom of each central panel  61   a  is a connector bracket  62 . Each connector bracket  62  is preferably provided one or more apertures enabling connector brackets  62  to be attached to opposite ends of drive beam  53 , while the outermost portion of telescoping rail assembly  61  is affixed to the interior side walls of frame  10 . Thus, retraction of drive assembly  50  toward the fully retracted position (shown in FIG. 5) will likewise upwardly extend central panel  61   a  of telescoping rail assembly  61 . Affixed to the upper end of each central panel  61   a  is a traction bar assembly bracket  63 . Each traction bar assembly bracket  63  has a looped upper arm  64 , the terminal end of which is preferably provided with apertures enabling each traction bar assembly bracket  63  to be affixed to traction bar assembly  70  via screws, bolts, or other similarly configured connectors. The loop in upper arms  64  enables each guide assembly  60  to be mounted on the interior walls of frame  10 , while traction bar assembly  70  is positioned outside of frame  10 , thus enabling easy insertion and removal of a container  30 . 
     As shown more particularly in the exploded view of FIG. 8, traction bar assembly  70  preferably includes a fixed jaw  71  and movable jaw  72  that together form a clamping mechanism for holding container  30 . Fixed jaw  71  is preferably provided apertures enabling fixed attachment of fixed jaw  71  to the front portions of looped upper arms  64 . A cam lever  73  is provided which enables movable jaw  72  to be moved from a locked position, in which movable jaw  72  is held tightly against fixed jaw  71 , to an open position, in which movable jaw  72  is held a distance away from fixed jaw  71 , thus enabling insertion of the upper portion of a container  30  between fixed jaw  71  and moveable jaw  72 . With reference to FIG.  8  and the front and cross-sectional views of FIG. 9, studs  74  extend into the rear face of cam lever  73 . Each stud  74  is provided a borehole at one end configured to receive a dowel  75 , which dowel  75  is positioned in boreholes in both cam lever  73  and studs  74 , such that a pivotal connection is established between cam lever  73  and studs  74 . The ends of studs  74  opposite the borehole are inserted through openings  85  extending through movable jaw  72  and openings  88  extending through fixed jaw  71 , and a fastening device such as an e-clamp  76  is used to hold the free ends of studs  74  on the back side of fixed jaw  71 . A plurality of spacers  78  and a wave spring  79  may optionally be provided on the free end of studs  74  between e-clamp  76  and the back face of fixed jaw  71 . As particularly shown in the cross-sectional view of FIG. 9, fixed jaw  71  is preferably indented on its rear side such that the outermost end of stud  74  does not extend beyond the outermost rear surface of fixed jaw  71 . This enables fixed jaw  71  to be flush mounted against the front faces of looped upper arms  64 . 
     In operation, cam lever  73  is in a substantially vertical orientation when moveable jaw  72  is in a locked position. Cam lever  73  is rotated about dowel  75  to a substantially horizontal orientation to place moveable jaw  72  in an open position. Spring members  77 , such as coil springs, surround each stud  74  between fixed jaw  71  and moveable jaw  72  and, when traction bar assembly  70  is fully closed, spring members  77  are compressed by each of fixed jaw  71  and movable jaw  72 . Openings  85  and  88  are stepped such that spring members  77  can be partially recessed in fixed jaw  71  and moveable jaw  72  when traction bar assembly  70  is in the fully closed position, as shown in cross section FIG.  9 . Likewise, when cam lever  73  is rotated to the open position, spring members  77  push moveable jaw  72  outward and away from the front face of fixed jaw  71  a small distance to enable insertion or removal of the top portion of a container  30  into the traction bar assembly  70 . 
     In order to aid in holding container  30  in place between fixed jaw  71  and movable jaw  72 , and as shown more particularly in FIGS. 9 and 10, movable jaw  72  is preferably provided a plurality of pins  80  having a sharpened head configured to pierce a peripheral portion, preferably a sealing edge, of container  30 . In addition to the clamping force provided between fixed jaw  71  and movable jaw  72 , pins  80  engage pin holes  90  in the front face of fixed jaw  71  to further ensure that container  30  will not inadvertently dislodge from carriage assembly  40  as the container  30  is pulled through roller assembly  18 . Positioning dowels  81  are also preferably provided extending outward from the rear face of movable jaw  72  and engaging boreholes  82  in the front face of fixed jaw  71  so as to guide the motion of movable jaw  72  when cam lever  73  is rotated to the open position and spring members  77  outwardly bias movable jaw  72 . Further, a dowel  83  may optionally be provided between the top rear face of movable jaw  72  and the top front face of fixed jaw  71  so as to encourage slight rotation of movable jaw  72  about dowel  83  when movable jaw  72  is biased away from fixed jaw  71 . 
     As shown in the exploded perspective view of FIG. 11, a preferred dispensing pump  100  preferably comprises a peristaltic pump head assembly  110 , a gear drive assembly  120 , arm  130  for attaching pump assembly  100  to the outside wall of frame  10 , a pump mount  140 , a pump lever  145 , and retaining pins  146 . As shown more particularly in the front, side, and top views of FIG. 12, peristaltic pump head  110  is affixed to and operatively engaged with gear drive assembly  120 , which in turn is operatively engaged with pump lever  145 . Pump mount  140  is positioned between gear drive assembly  120  and pump lever  145 , and has apertures extending through its bottom portion for attaching pump mount  140  to arm  130  via screws, bolts, or similarly configured connectors. Pump mount  140  is preferably provided an arcuate plate  141  having a series of openings therein configured to receive retaining pins  146 . With pump lever  145  positioned between two retaining pins  146  attached to plate  141 , the pump stroke may be adjusted to provide for dispensing only the requisite amount of material from container  30 . Moreover, as multiple openings are provided in plate  141 , such stroke may be varied simply by removing a retaining pin and replacing it in another opening which affords the proper stroke for the particular application. 
     It should be noted that dispensing pump  100  is thus particularly configured to dispense a predetermined volume of material from container  30  upon a single dispensing operation, e.g., a single manual operation of pump lever  145 , with the length of the stroke determining the amount of material to be dispensed. Thus, for a given stroke, the apparatus of the instant invention will consistently dispense the fixed, predetermined volume of material for each dispensing operation. 
     As shown more particularly in FIG. 13, gear drive assembly  120  comprises an input shaft  121  that receives torque transferred from pump lever  145  and directs the same to a pump gear  122  within gear drive housing  123 . Housing  123  is preferably equipped with an opening  124  at the bottom of its rear side, which opening is adapted to receive a pump pinion  111  (FIG. 14) of pump head assembly  110 , which pinion  111  operatively engages pump gear  122  so as to transfer torque to pump head assembly  110 . As shown in the exploded view of FIG. 14, pump pinion  111  operatively engages the drive shaft  115  of roller assembly  112 . Thus, it can be seen that rotation of pump lever  145  will ultimately cause the operation of roller assembly  112  in peristaltic pump assembly  100 . When assembled, tubing extends from the interior of container  30  to peristaltic pump assembly  100  such that rotation of pump lever  145  and the resultant rotation of roller assembly  112  results in withdrawal of material from container  30  and dispensing of the desired amount of material. 
     Peristaltic pump assembly  100  is preferably provided with either three or four rollers  117  in order to provide users with varying levels of precise dosing, as well as oxygen and bacteria barriers to prevent migration of bacteria back into container  30 . The peristaltic pump is configured such that the greater the number of rollers provided the shorter the stroke that is required to dispense a portion of product from container  30 . Further, the handle stroke, particular thickness of tubing extending from container  30  to peristaltic pump assembly  100 , and number of rollers on peristaltic pump assembly  100  may be varied and optimized to provide the necessary dosing for any given application. 
     In operation of the portion control dispenser depicted in FIG. 1, a container  30  is attached to mount  70  with the exterior roller  20  rotated away from interior roller  21 . The weight of a full container causes the carriage assembly  40  to be fully lowered. Exterior roller is closed over the end of container  30  and latched in place by plunger  22 , thereby pinching container  30  between interior roller  21  and exterior roller  20 . As a user depresses the pump lever  145  of the peristaltic pump assembly  100 , a controlled amount of product is dispensed. As more product is dispensed, the resistance provided by product in container  30  against rollers  20  and  21  is lessened, enabling the carriage assembly  40  to be raised and drawing container  30  between the rollers  20  and  21  during its upward travel. Such action aids gravity by continuously directing all remaining product in the container  30  toward the dispensing end, in turn minimizing waste that results from undispensed product. 
     In the particular embodiment of the instant invention depicted in FIG. 1, the dispensing apparatus is shown with carriage  40  at the top of its stroke. At such final position, it can be seen that rollers  20  and  21  have flattened container  30  as it has been drawn upward between the rollers so as to continuously direct all material therein towards the bottom of container  30 . This ensures dispensing of the entire content of container  30 , thus minimizing or altogether eliminating waste associated with prior art dispensing devices. Moreover, the construction of the portion control dispenser of the instant invention enables the entire volume of product stored within container  30  to be kept sterile until dispensed. 
     It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. Having now fully set forth the preferred embodiments and certain modifications of the concept underlying the present invention, various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept. It should be understood, therefore, that the invention may be practiced otherwise than as specifically set forth herein. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. 
     While specific values, relationships, materials and steps have been set forth for purposes of describing concepts of the invention, it should be recognized that, in the light of the above teachings, those skilled in the art can modify those specifics without departing from basic concepts and operating principles of the invention taught herein.