Abstract:
The dispenser is for dispensing viscous products, has an ergonomic shape, and an automatic closure. The closure opens promptly upon initiation of an actuator and before the flow of viscous product from the dispenser. Further, the closure closes the dispenser outlet at the end of the return of the actuator to its rest position. Further, an outlet valve from a pump chamber remains open as an inlet valve to the pump chamber opens. This causes a suckback of viscous product near the dispenser outlet to flow into the dispenser. The automatic closure does not close as dispenser outlet until the suckback of viscous product has occurred. The automatic closure also functions as a knife or blade to assist in cutting the viscous product to maintain cleanliness and hygiene of the package.

Description:
BACKGROUND OF INVENTION 
     This invention relates to a dispenser for viscous or viscous products, which has a closure, which closure automatically closes the dispenser exit. More particularly, this invention relates to a dispenser having a closure where the closure opens before the flow of viscous product and closes after the flow of viscous product. The closure acts as a door or knife to assist in cutting off the product flow to maintain cleanliness. 
     These are a variety of dispensers for viscous products (viscosity range 150,000-600,000 CPS), which include a closure for the exit. Such a closure is used for hygienic reasons to keep the viscous product isolated from the environment when the dispenser is not in use. Such a closure could be one that is opened and closed manually. The closure could be threaded onto dispenser exit or attached to the dispenser and opened via a hinge. However, in all of these embodiments a person would have to remember to put the closure in place after use. It is preferred that the closure be automatically activated to open and close the dispenser exit when the dispenser is actuated, and in addition assist in product cutoff. 
     Dispensers that have automatically opening and closing closures for a dispensing outlet are disclosed in U.S. Pat. No. 4,684,044; U.S. Pat. No. 4,691,847; U.S. Pat. No. 4,715,518 and U.S. Pat. No. 4,872,596. In several of these patents the closure over the dispensing outlet also functions as a valve that is necessary for the operation of the dispenser. In the present dispenser the pump valves are located within the pump body with the closure solely being for sanity purposes and to keep the product at the dispenser opening from drying out and forming a crust at the dispenser outlet, and stopping product flow in a clean manner by assisting product cutoff. 
     SUMMARY OF INVENTION 
     The present dispenser has an ergonomic shape and is of the type where the outlet of the dispenser is automatically covered by a closure when the dispenser is not in use and is being stored. An objective is to have the outlet of the dispenser covered for sanitary reasons, to prevent the product in the area of the outlet from drying out and forming a crust or dried plug at the outlet exit. Another is for the closure to assist in the cutoff of any part of the product as the main charge of viscous product is being sucked back into the dispenser upon the cessation of dispensing. 
     The ergonomic shape is to make the dispenser easy to grip and to hold in one hand, and to operate using one hand. This alone provides a clear difference compared to current package forms for dispensing viscous products. 
     The dispenser is comprised of a product chamber and a pump chamber. The product chamber will, in one embodiment, be unitary with the dispenser and in another embodiment be a refill container that can be inserted into the dispenser to replace a container from which all of the product has been dispensed. A refill container would be inserted into the dispenser through the bottom of the dispenser. 
     The dispenser is comprised of a body with a supporting base at a lower end. On the upper end there is a dispensing outlet and adjacent the dispensing outlet, an actuator. The dispenser outlet is closed by a pivoting outlet door closure. Upon depressing the pump actuator the outlet door closure is pivoted open prior to the initiation of product flow from the dispenser. It remains open during dispensing and closes after dosing of the product has been completed. However, it does not close until a portion of the product has been drawn back down into the dispenser, i.e, sucked back, by the internal valving system. This will assist the closure as it moves to close the dispensing outlet. The closure also will cutoff product any portions of the product that have not flowed back into the dispenser. 
     Upon actuation of the dispenser, by depressing the actuator, product in the pump chamber is expelled from the pump chamber past the pump chamber outlet valve, through the outlet channel and outlet channel extension to the outlet opening. As the actuator is being depressed, a closure covering the outlet opening immediately is opened. This closure is opened prior to the flow of product from the dispenser. After the opening of the closure, a portion of the product is dispensed from the dispenser. Upon release of the actuator, the flow of product ceases and some of the product is sucked back down into the dispenser from the region of the dispenser outlet prior to the closure closing. There is a delay in the closing of this closure to preclude contact of the closure with the viscous product being dispensed. This is accomplished by keeping the pump chamber outlet valve open during part of the return of the actuator to its rest position and the structure of the connection of the actuator to the closure. The release of the actuator returns it to the upright position and refills the dispensing chamber with the next dose or product. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     FIG. 1 is a side elevation view of the dispenser. 
     FIG. 2 is a top plain view of the dispenser. 
     FIG. 3 is a partial elevation view of the dispenser in section along line  3 — 3  of FIG.  2 . 
     FIG. 4A is a partial elevation view of the dispenser as shown in FIG. 3 primed but prior to dispensing. 
     FIG. 4B is a partial elevation view of the dispenser as shown in FIG. 3 in the mode of dispensing. 
     FIG. 4C is a partial elevation view of the dispenser as shown in FIG. 3 after the step of dispensing and with product being drawn into the pump chamber. 
     FIG. 5 is an exploded view of the pump head of the dispenser. 
     FIG. 6 is a partially assembled pump head in a non-dispensing mode. 
     FIG. 7 is a partially assembled pump head in a dispensing mode. 
    
    
     DETAILED DESCRIPTION 
     The dispenser will be described in more detail with reference to the drawings. The figures disclose the dispenser in its preferred embodiments with modifications being within the present concept. 
     The dispenser  10  of FIG. 1 has an ergonomic shape to the sidewalls  18  of the dispenser. This ergonomic shape makes the dispenser easier to hold and to use in a one handed manner. The dispenser has a base  12 , dispensing outlet port  16  and an actuator button  14 . The dispensing outlet  16  and actuator button are better shown in the top plan view of FIG.  2 . 
     FIG. 3 is a vertical sectional view of the pump portion of the dispenser  10 . Chamber  20  contains the product to be dispensed and comprises container  11 , which terminates in fitment  13 . This container can be for one time use or can be replaceable. When replaceable, one can be removed and another, a refill, inserted. These will be removed and inserted through the bottom of the dispenser. The portion above product chamber  20  is the pump section. The sidewall  18  extends from the product chamber  20  to the sidewall  19  of the pump section. During dispensing product flows through aperture  41  that is closed by inlet valve  36 . This inlet valve has travel limit stops  38  and an upper valve top  40 , which opens and closes aperture  41 . After the product passes by inlet valve  36  it flows into pump chamber  22 . This pump chamber is formed by a lower wall of inlet valve  36  and outlet valve  46 , pump chamber sidewall  24  and pump piston  26  as the upper wall. This pump piston rides along pump chamber wall  24 . A piston shaft  28  extends up from piston base wall  27  and terminates in piston pad  32 . Surrounding piston shaft  28  is spring  30 . Actuator pad  15  contacts the piston pad  32  when actuator  14  is depressed. The piston shaft  28  rides in channel guide  25 , which via wall  23  is a part of pump chamber wall  24 . 
     As noted, outlet valve  46  also forms a lower part of the pump chamber  22 . During dispensing outlet valve  46  extends downwardly to allow product from pump chamber  22  to flow to outlet channel  42  and outlet channel extension  44 . Outlet channel extension  44  is closed by reciprocating closure  50 , which closes outlet  16 . This reciprocating closure  50  starts opening prior to product flow in the outlet channel extension and closes after product at the dispenser outlet has flowed back into the dispenser. However this closure  50  will assist in cutting off any product segment extending beyond the dispenser outlet. This will be the case for products that are stringy, i.e. have string-like segments extending from the main body of product that is flowing back into the outlet channel extension. 
     FIG. 4A shows the dispenser  10  primed for use, but in a rest condition. Product  70  is in the product chamber  20 , pump chamber  22 , outlet channel  42  and the outlet channel extension  44 . FIG. 4B shows what occurs upon the actuation of the dispenser  10 . Actuator  14  is depressed with actuator pad  15  contacting piston shaft pad  32 . Piston  34  then moves downwardly displacing product  70  from pump chamber  22 . The force put on product  70  in pump chamber  22  closes inlet valve  36  and forces outlet valve  46  to open allowing product  70  to flow up outlet channel  42  and through outlet channel extension  44  to the outlet  16 . The closure  50  opens prior to the flow of product  70  from outlet channel extension  44  to the outlet. FIG. 4C shows the pump dispenser  10  returning to the rest position. As the downward force is released on actuator  14 , it moves upwardly under the force of spring  30 , which also pulls piston  34  upwardly. Upon piston  34  moving upwardly, inlet valve  36  is opened and product  70  flows up into pump chamber  22  due to the reduced pressure in pump chamber  22 . Outlet valve  46  is closed most of this time. Inlet valve  36  will close as soon as piston  34  starts a downward stroke. This happens upon depressing actuator  14 . However there is a slight delay in the opening of outlet valve  46 . Closure  50  will open promptly upon piston  34  starting a downward stroke. In this way the closure is opening prior to the flow of product into the outlet channel. 
     A key feature that is built into the dispenser  10  is a suckback of product in outlet channel extension  44  upon the start of the actuator being returned to its rest position. As the piston is being retracted, outlet valve  46  remains open for a short period of time as inlet valve  36  is opening which allows product in outlet channel extension  44  to move downwardly away from outlet closure  50 . This is a result of the reduced pressure in pump chamber  22 . This prevents the build-up of product around closure  50 . 
     FIG. 5 shows the mechanics of the pump head in an exploded view. Starting at the lower end of the pump, there is valve holder  45 . Inlet valve  36 , which has valve top  40  and valve stops  38 , fits into the outlet valve holder  45  and controls flow through aperture  41 . Inlet valve top  40  contacts outlet valve top  46  with the inlet valve stop  38  contacting lower locking ridge  43  of outlet valve holder  45 . The outlet valve top  46  flexes to function as a valve. Piston  26  has wiper walls  34  with piston shaft  35  extending upwardly. This piston  26  fits into pump chamber  22  defined by sidewall  24 . Above pump chamber  22  is pump chassis  48 . This pump chassis carries the actuator mechanism; the outlet channel  42  and outlet channel extension  44 , and closure  50  with its actuating mechanism. The actuating mechanism is comprised of actuator  14 , piston shaft  28  and piston shaft pad  32 . The outlet channel  42  flows product outlet channel extension  44  and is a support for actuator hinge pin  60 . Actuator hinge pin holder  58  fits onto actuator hinge pin  60  on each side. This then attaches actuator  14  to pump chassis  48 . Closure hinge pin  68  Is mounted adjacent the end of outlet channel extension  44 . Closure hinge pin holder  69  fits over closure hinge pin  68  at the end of the outlet channel extension  44  and attaches the closure to outlet extension  44 . Closure connecting unit  52  attaches the closure  50  to the actuator  14 . In this way the closure  50  opens prior to the movement of product  70  in the outlet channel extension  44 . It also will not close outlet channel extension  44  with closure  50  until product  70  has been sucked back into the outlet channel extension about 3 mm to 8 mm. 
     The closure-connecting unit  52  has closure-connecting unit hinge pin  61 , which fits into actuator hinge pin holders  62 . On the other end of the closure-connecting unit  52  are closure connecting unit hinge pin holders  66 . Closure hinge pins  64  will fit into connecting unit hinge pin holders  66 . This is the structure of a preferred structure for the present pump section. 
     FIG. 6 shows the pump mechanism at rest. The closure  50  is closing outlet  16 . The spring  30  is fully extended. The closure mechanism with all connections of hinge pins to hinge pin holders is shown. FIG. 7 shows the pump mechanism actuated. It is shown here that when actuator  14  is depressed that it rotates around an actuator connecting hinge pin  60 , pulling connecting unit  52  toward actuator  14  to open closure  50 . The reverse occurs upon the release of actuator  14  until the pump mechanism reaches the rest state as shown in FIG.  6 . As the actuator  14  is depressed, the door  50  is opened before the actuator  14  has been depressed to any significant extent. Upon depression of actuator  14 , the actuator extension  54  rotates toward the actuator pulling connecting unit  52  in the same direction. This, then pivots closure  50  to be open. This is accomplished by means of the arrangement of hinge pins and hinge holders. The connecting unit rotates on hinge pin  61  and the closure, on hinge pin  64 . The movement of these parts, upon depressing the actuator, causes the closure  50  to open with the opposite occurring when the pressure on the actuator is released. The opening is a prompt opening and the closing a delayed closing. 
     The dispenser can be constructed of a wide range of materials with thermoplastics being the material of choice. The spring usually would be metallic. The preferred thermoplastics are polyethylenes and polypropylenes. These materials usually are formed into the various parts by injection molding and extrusion molding. However, any known molding technique can be used. The dispenser parts can be hand or machine assembled. The type of assembly to be used will depends on the number of units to be made. 
     The product can be any viscous product but this dispenser is very useful in the dispensing of dentifrices. However this is a preferred product to be dispensed and is not limited to dispensing such products.