Abstract:
A container-dispenser for products which are viscous fluids such as liquid soap, which allows one-handed operation to supply a controlled amount of viscous fluid in a convenient and clean way and protects the contents from exposure to air. The container body is equipped with a piston that applies constant pressure on the product within the container. By applying force on a valve from above, a passage is opened allowing the product to be dispensed through the top of the container. When the pressure on the valve is relieved, the opening is closed, preventing further dispensing of the product. Excess product is temporarily retained until needed in the “bowl” resulting from the convex shape of the top of the container.

Description:
FIELD AND BACKGROUND OF THE INVENTION 
     The present invention relates to a dispenser of viscous fluids and, in particular, a container-dispenser that can be used with one hand to supply a controlled amount of viscous fluid in a convenient and clean way. 
     Many useful products are supplied as viscous fluids, commonly referred to as lotions, gels, greases, suspensions, creams, jellies, colloids, oils or salves. Such products include cosmetics, skin-care products, hygiene products such as fluid soap, or topical medications. 
     One method known in the art is to supply these products in wide-mouthed containers with lids, such as jars. Once the jar is open, the user can remove a required amount of product with the use of the fingers or aids such as cotton swabs and cotton balls. The disadvantages of jars are manifold. Throughout the time during which the product is in use it is exposed to the open air and light leading to drying out and other changes which comprise the desired properties of the product. Closing the jar after removal of an amount of product is inconvenient as opening and closing of the jar requires a relatively complex motion which cannot be done if one hand is occupied or if the hands are dirty. When repeated removal of the product from the jar is necessary, contamination may occur. For instance remnants of cosmetics on a cotton-ball when using cold cream for facial cosmetic removal may contaminate the product in the jar. The outside surface of the jar can get dirty from the product on the hands of the user. When the container is almost empty it is difficult to remove the last traces of the product for use. With certain products it is often difficult to remove the exact required amount. 
     In the art, a pump-action dispenser attached to the container holding the product is often used. This type of dispenser protects the product from light and from exposure to air, but often requires the use of two hands. Even in the best of cases, the use of one hand to bring the product onto an aid such a cotton-ball is difficult. Dripping from or the presence of dried product on the pump-spout often occurs. Often the last traces of the product are not removable from a container equipped with a pump-action dispenser. 
     In the art, it has been proposed to fix various types of container-dispensers to a wall or table, making one-handed dispensing convenient. However, it is often undesirable to impossible to fix a dispenser in one place. 
     There is therefore a need for a container-dispenser for viscous a fluid which overcomes the disadvantages of other container-dispensers known in the art. 
     SUMMARY OF THE INVENTION 
     The present invention is a container-dispenser which can be used with one hand to supply a controlled amount of viscous fluid in a convenient, easy to use way which protects the contents of the container-dispenser from exposure and contamination, and yet allows use of the entire contents of the container. 
     According to the teachings of the present invention there is provided a container-dispenser, for containing and dispensing a viscous fluid, made up of (a) a parallel-walled container body, formed with at least one wall defining a volume with an axis parallel to the wall, the container body having a top edge, (b) a piston configured to sealingly slide parallel to the axis within the container body, (c) a dispensing head with a top surface and a dispensing hole extending from the top surface through the dispensing head, the dispensing head connected to the top edge of the container body such that the wall or walls, the piston and the dispensing head together define a storage volume for the viscous fluid, the top surface of the dispensing head being inwardly hollowed, and (d) a normally-closed manually-operable valve mechanism associated with the dispensing hole so as to selectively block and unblock the dispensing hole to the passage of the viscous fluid. 
     According to a further feature of the present invention, a part of the valve mechanism protrudes from the dispensing hole and the valve mechanism is configured to unblock the dispensing hole when a downwards force is applied on that protruding part. 
     According to a further feature of the present invention, there is provided a valve mechanism made up of a plug configured to physically block the dispensing hole when the valve mechanism is in a closed state, the plug configured to partially protrude from the dispensing hold and a mechanism for biasing the plug to the closed state. 
     According to a further feature of the present invention, there is provided a container-dispenser wherein the container body is substantially cylindrical. 
     According to a further feature of the present invention, there is provided a dispensing head attached to the top edge of the container-body. 
     According to a further feature of the present invention, there is provided a dispensing head integrally formed with the top edge of the container-body. 
     According to a further feature of the present invention there is provided a pressure-applying mechanism configured to apply pressure to the bottom side of the piston. 
     According to a still further feature of the present invention the pressure-applying mechanism provided is a spring deployed so as to apply a force pushing the piston upwards within the container body. 
     According to a still further feature of the present invention, there is provided a foot operatively connected to the bottom side of the piston, the foot configured to stably support the container-dispenser on an underlying surface so that the container body and the dispensing head are at least partially supported by pressure within the viscous fluid. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein: 
     FIG. 1 is a schematic cross-section side view of a first embodiment of a container-dispenser, constructed and operative according to the teachings of the present invention; and 
     FIG. 2 is a schematic cross-section side view of a second embodiment of a container-dispenser, constructed and operative according to the teachings of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention is a container-dispenser for viscous fluids. The principles and operation of container-dispensers according to the present invention may be better understood with reference to the drawings and the accompanying description. 
     First, a general description of a container-dispenser according to the present invention is made with reference to FIG.  1 . Depicted in FIG. 1, is a parallel-walled container body  12 . A piston  14  is configured to sealingly slide within container body  12 . Connected to the top edge of container body  12  is a dispensing head  16  with an upper surface  20 . There is a dispensing hole  24  extending from upper surface  20  through dispensing head  16 . Upper surface  20  is inwardly hollow in form, that is to say, it forms a recess  22  wherein any excess of the dispensed product is temporarily retained until needed. It is to be understood that by inwardly hollow is meant a shape that effectively contains dispensed product at upper surface  20  such as a concave, a parabolic, a conical or other recessed shape. Deployed within dispensing hole  24  is a normally-closed manually-operable valve mechanism (elements  26 ,  28 , and  30  taken together). By default the valve mechanism is in a closed state, blocking dispensing hole  24 . When a force applied by a user actuates the valve mechanism, the valve mechanism is brought to an open state, unblocking dispensing hole  24  and allowing passage of product  18  out through dispensing hole  24  to be retained in recess  22 . 
     It is clear to one skilled in the art that various different types of valve mechanisms can be used in the present invention. By way of example, two specific types of valve mechanisms are described in the following descriptions. 
     Referring now to a specific embodiment of present invention, FIG. 1 shows a first embodiment of a container-dispenser according to the present invention, generally designated  10 . Generally speaking, container-dispenser  10  is composed of three parts, container body  12 , piston  14  and dispensing head  16 . Container body  12  has the shape of a hollow tube, being preferably cylindrical. Piston  14  fits inside container body  12  and is configured to sealingly slide upwards and downwards within container body  12 . In the embodiment of the present invention depicted in FIG. 1, dispensing head  16  is non-removably attached or integrally formed with the top edge of container body  12 . Pressure applied to the bottom surface  20  of piston  14  applies pressure on product  18 . As long as the valve mechanism is not open, dispensing hole  24  is blocked and product  18  is contained within the volume delineated by container body  12 , piston  14  and dispensing head  16 . 
     In the embodiment of the present invention shown in FIG. 1, a dispensing spring  32  is provided to provide an upward force on piston  14 . Dispensing spring  32  acts against bottom plate  34  that is removably attached to container body  12  by threading. To prevent leakage from between container body  12  and the edges of piston  14 , piston  14  slides sealingly in container body  12 , that is to say piston  14  is further configured so as to prevent such leakage. This can be done by producing piston  14  of a material and to such a tolerance that product  18  cannot escape, or through the addition of a separate seal (not appearing in FIG.  1 ). 
     The valve-mechanism is configured as to allow one-handed control of the amount of product dispensed and upper surface  20  of dispensing head  16  is configured to provide a containment volume for the dispensed product. In the embodiment of the present invention shown in FIG. 1, the dispensing of product  18  through cone-shaped dispensing hole  24  is effected by the valve mechanism, made up of a plug with a parabolic cross-section  26 , a spring  28 , and a counter-force ledge  30 . 
     Plug  26  is configured so that when placed with its narrow tip through dispensing hole  24 , plug  26  protrudes to some extent but cannot pass completely through dispensing hole  24 . The outer surface of plug  26  and the internal surface of dispensing hole  24  are so configured that when in place in a closed state plug  26  blocks dispensing hole  24  preventing escape of product  18  through dispensing hole  24 , even when product  18  is under pressure applied by piston  14 . Furthermore, plug  26  substantially prevents the entrance of air or other undesirable materials and prevents evaporation of solvent or drying out of product  18  contained within container-dispenser  10 . 
     Counter-force ledge  30  is operatively connected to dispensing head  16  so as to be fixed in place and so as not to obstruct the flow of product  18  through dispensing hole  24 . Spring  28  is placed between plug  26  and counter-force ledge  30  in such a way as to exert a force separating counter-force ledge  30  from plug  26 . Because counter-force ledge  30  is fixed in place, plug  26  is forced upwards, blocking dispensing hole  24 , and preventing escape of product  18  through dispensing hole  24 , even when product  18  is under pressure applied by piston  14 . 
     The valve mechanism of dispensing head  16  is activated by a force applied by the user to the part of plug  26  protruding thorough dispensing hole  24 . The force applied by the user depresses plug  26  downwards, compressing spring  28  and opening a passage through which product  18  can flow outwards, past counter-force ledge  30 , through dispensing hole  24  to accumulate on the upper surface  20  of dispensing head  16 . When the desired amount of product  18  has accumulated, the user stops applying pressure on plug  26 . Spring  28  pushes plug  26  upwards, causing plug  26  to block dispensing hole  24 . Further undesired escape of product  18  through dispensing hole  24  is prevented. 
     As it escapes through dispensing hole  24 , product  18  can be used as desired. In FIG. 1, upper surface  20  of dispensing head  16  is concave in form. Product  18  escapes through dispensing hole  24  to be used, whereas excess product is temporarily retained within recess  22  produced by this concave form, which serves as a “bowl”. Excess escaped product  18  retained in “bowl”  22  is used as desired. If too much product is dispensed or the product that is accumulated in the bowl becomes contaminated, the unused product can be easily removed. 
     An additional embodiment of the container-dispenser of the present invention is depicted in FIG.  2 . Salient differences between the embodiment of the present invention depicted in FIG.  1  and that depicted in FIG. 2, generally designated  40 , include a plug  42  with a substantially conical cross-section and a removably attached dispensing head  58 . Attachment of dispensing head  58  to container body  46  is done with the aid of threads  44 . Furthermore, container body  46  is provided with a ledge  48  around at least part of its bottom edge. Ledge  48  is configured so as to engage piston  50  in such a way so that piston  50  cannot fall out in a downwards direction from container body  46 . Piston  50  is configured with a foot  56  that allows container-dispenser  40  to stand on foot  56  in a stable fashion. 
     The upwards force that pushes product  54  outwards in the embodiment of the present invention depicted in FIG. 2 is generated by the force applied by the user when pressing plug  42  downwards, as well as by the weight of container body  46  and dispensing head  58 . 
     Because dispensing head  58  is removably attached to container body  46 , it is possible to refill container-dispenser  40  if product  54  is used up. This is done by unscrewing dispensing head  58  from container-dispenser  40 , extending piston  50  outwards so that it makes contact with ledge  48 , pouring more product  54  into the volume defined by container body  46  and piston  50 , and subsequently reattaching dispensing head  58 . 
     The operation of the embodiment of the present invention depicted in FIG. 2 is otherwise analogous to that described before and is clear to one skilled in the art. Therefore, further details of the use of the embodiment of the present invention depicted in FIG. 2 are not provided. 
     It will be appreciated that the above descriptions are intended only to serve as examples, and that many other embodiments are possible within the spirit and the scope of the present invention.