Abstract:
Radial pressure exerted against a deflectable sidewall of an outer container initiates a chemical reaction in which the temperature of a product in an inner cup is changed.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention generally relates to an arrangement that adds or removes heat from a product, such as a food, beverage, medicine, or like product and, more particularly, to promoting user acceptance of the arrangement by enhancing its operation.  
         [0003]     2. Description of the Related Art  
         [0004]     Self-heating or self-cooling arrangements are known in which a product, typically a beverage, is heated or cooled by employing two chemical reactants which are stable when separated, but which produce an exothermic or an endothermic reaction when mixed. U.S. Pat. No. 4,793,323 shows one example of a single-use, self-heating container for liquids or solids, in which a breakable membrane keeps the reactants apart, and a breakable member is actuated by a user to break the membrane and allow the reactants to mix to form the chemical reaction that changes the temperature of the product.  
         [0005]     As advantageous as the known self-heating containers are, experience has shown that the actuation by the user is difficult for at least some users to perform. More specifically, the user is expected to axially depress an actuator button provided on the bottom of the container. Even if the user is prompted as to the location of the actuator button, the user is required to invert the container, and then exert a significant amount of physical force to depress the button along the axis of the container for the axial distance required to break the membrane and initiate the self-heating action. Some users, particularly the elderly and children, do not have the strength to activate the self-heating action.  
       SUMMARY OF THE INVENTION  
     OBJECTS OF THE INVENTION  
       [0006]     Accordingly, it is a general object of this invention to promote user acceptance, and to enhance the operation, of arrangements that add or remove heat from a product.  
         [0007]     More particularly, it is an object of the present invention to reduce the amount of physical force required to activate the temperature-changing action.  
         [0008]     Still another object of the present invention is to provide a reliable arrangement for, and method of, selectably changing the temperature of a product.  
       FEATURES OF THE INVENTION  
       [0009]     In keeping with the above objects and others which will become apparent hereinafter, one feature of the present invention resides, briefly stated, in an arrangement for, and a method of, changing a temperature of a product, typically a food or a beverage, comprising an outer container, preferably made of a thermally insulating material, having a side wall bounding an interior and spaced radially from an axis, and an inner cup, preferably made of a thermally conductive material, fixedly mounted within the interior of the container and having a chamber for containing the product. Preferably, the cup and the container have juxtaposed flanges fused together by spin-welding.  
         [0010]     A breakable membrane, for example a circular, thin foil, is fixedly mounted within, and subdivides, the interior of the container into a pair of compartments. The container is formed with an internal annular shoulder, and a circular periphery of the membrane is adhered to the shoulder. A pair of reactants is respectively contained in the compartments, and the reactants are kept apart by the membrane prior to use. For example, the reactants may be water and anhydrous calcium oxide or calcium chloride which, when mixed, produce an exothermic chemical reaction.  
         [0011]     A breaking member is mounted within the interior of the container in a juxtaposed relationship with the membrane. The breaking member is at least partially supported by the internal shoulder of the container. In accordance with this invention, a radial pressure is exerted by the user on the side wall of the container, and this radial pressure causes the breaking member to break the membrane and allow the reactants to mix and produce the chemical reaction that changes the temperature of the product in the cup.  
         [0012]     In contrast to the known art, the temperature changing action is not initiated by inverting the container to expose an actuator button on the bottom of the container. Nor is the temperature change actuated by axially depressing a button with a significant amount of force. Instead, the upright container is radially constricted by squeezing the side wall adjacent the shoulder between opposed fingers. The user need only hold the container in one&#39;s palm and close his or her fingers around the side wall in the action of making a fist. This fist-making movement is much easier for the user to perform as compared to the depression of a button.  
         [0013]     The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1  is an exploded view of an arrangement in accordance with this invention;  
         [0015]      FIG. 2  is an enlarged sectional view of the arrangement of  FIG. 1  after assembly;  
         [0016]      FIG. 3  is a view analogous to  FIG. 2 , after exertion of radial pressure on a side wall of an outer container;  
         [0017]      FIG. 4  is a sectional view taken on line  4 - 4  of  FIG. 2 ;  
         [0018]      FIG. 5  is a sectional view taken on line  5 - 5  of  FIG. 2 ;  
         [0019]      FIG. 6  is a bottom plan view of a breaking member for use in the arrangement of  FIG. 1 ;  
         [0020]      FIG. 7  is a perspective view of the breaking member of  FIG. 6 ;  
         [0021]      FIG. 8  is a top plan view of a partially removed seal on a product cup for use in the arrangement of  FIG. 1 ; and  
         [0022]      FIG. 9  is a top plan view of a sip lid for use in the arrangement of  FIG. 1 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0023]     As best shown in  FIGS. 1-2 , an arrangement in accordance with this invention includes an outer container  10  having a side wall  12  bounding an interior, an inner cup  14  fixedly mounted within the interior of the container  10 , a breakable membrane  16  fixedly mounted within the interior of the container  10  and subdividing the interior into a pair of compartments  18 ,  20 , a pair of reactants  22 ,  24  respectively contained in the compartments  18 ,  20  and kept apart by the membrane  16  prior to use, and a breaking member  26  mounted within the container  10 , preferably above the membrane  16 , and operative for breaking the membrane  16 , as described below, to allow the reactants  22 ,  24  to mix and form a chemical reaction that changes the temperature of a product contained in the cup  14 . A seal  28  seals the product within the cup  14 . An apertured sip lid  30  is optionally mounted over the seal  28  and over the container  10 .  
         [0024]     The container  10  is symmetrical about an upright axis  32 , and the side wall  12  circumferentially surrounds the axis  32 . The side wall  12  is preferably frusto-conical or cylindrical. The container  10  is formed with an interior annular shoulder  34  on which a circular periphery of the membrane  26  is adhesively secured. A circular periphery of the breaking member  26  also rests on the shoulder  34 . The compartment  18  above the membrane  16  is filled with one of the reactants  22 , for example, water, and the compartment  20  below the membrane  16  is filled with the other of the reactants  24 , for example, anhydrous calcium oxide or calcium chloride. Other reactants are contemplated by this invention, and the positions of the reactants could be reversed, that is, the water could be in the lower compartment, while the anhydrous calcium oxide or calcium chloride could be in the upper compartment. The container  10  is preferably constituted of a thermally insulating material, for example, a thermoformed foamed polypropylene, and the side wall  12  is deformable radially inwardly, as described in detail below.  
         [0025]     The inner cup  14  contains the product and can consist of a thermoformed plastic or is preferably constituted of a thermally conductive material, for example, a polyethylene coating over an aluminum core formed by a deep draw stamping process. The product can be virtually anything, but is preferably a beverage, such as coffee or tea, or a soup, or a foodstuff. The seal  28  seals the product within the cup. The seal  28 , as best shown in  FIGS. 4 and 8 , includes an annular rim  36  mechanically crimped over a radial annular flange  38  of the cup  14 , and a diaphragm  40  adhesively mounted on the rim  36  and peelably removable from the rim  36  by pulling on a pull tab  42 . The rim, diaphragm and pull tab are preferably constituted of aluminum which is stamped and die cut into their illustrated shapes. The seal  28  hermetically seals the product before and during the temperature change. Once the temperature change has been achieved, the pull tab is pulled to at least partially remove the diaphragm and gain access to the product.  
         [0026]     The membrane  16  is a thin, tearable foil die cut into a circular shape and preferably constituted of aluminum. An adhesive at its periphery adheres the membrane to the shoulder  34  and is preferably thermally activated.  
         [0027]     The breaking member  26 , as best seen in  FIGS. 6-7 , is an injected molded polypropylene plastic operative to pierce and tear the membrane  16 . The breaking member  26  has a plurality of radial arms  44 ,  46 ,  48 ,  50  having inner ends connected by respective living hinges  52  to a central, pointed barb  54  that lies along the axis  32  and faces the membrane  16 . A plurality of abutments  56 ,  58 ,  60 ,  62  is connected by respective living hinges  64  at outer ends of the arms. The abutments are curved to conform to the curvature of the side wall  12  against which the abutments contact (see  FIG. 5 ).  
         [0028]     As shown in  FIG. 2 , the membrane  16  is intact, and the breaking member  26  rests on the membrane  16  and the shoulder  34 . If a radial pressure is exerted on the side wall  12  adjacent the shoulder  34 , as schematically illustrated by the opposing fingers  66  of a user&#39;s hand moving in the directions of arrows  68 , then the side wall  12  deforms inwardly, the abutments are pushed inwardly, the living hinges  64  bend, the arms are pushed downwardly, the living hinges  52  bend, and the pointed barb  54  moves downwardly and pierces the membrane  16 . The reactant  22  in the upper compartment  18  flows downwardly through the ruptured membrane and chemically reacts with the reactant  24  in the lower compartment  20 .  
         [0029]     To promote the speed and efficiency of the chemical reaction, the user can shake the arrangement, typically for about 10-20 seconds, and can even invert the arrangement and allow it to stand, typically for less than two minutes. In the preferred embodiment, about 28 grams of a granulated calcium chloride (grain size 1-2 mm) are used. The liquid reactant need not be pure water, but can be mixed with an acid, such as oxalic acid. In about one minute&#39;s time, the temperature of the exothermic reaction caused when water and calcium chloride interact rises from a room temperature of about 19° C. to a temperature of about 60° C., which is sufficient to heat the product within the cup.  
         [0030]     The radial pressure is exerted between the opposing fingers  66 . As shown, there are four zones, one corresponding to each abutment  56 ,  58 ,  60 ,  62 , at which the finger pressure should be applied. These zones can be highlighted and marked on the side wall  12 . Otherwise, it is sufficient for the user to merely hold the container in his or her hand and grip tightly as if making a fist. This radial squeezing is continued until resistance is felt when the side wall  12  engages the cup  14 . This cup thus serves as a safety stop for preventing the user from completely crushing the arrangement. A label can be applied on the side wall which not only provides sales and marketing information, but also prominently displays the finger pressure zones.  
         [0031]     Once the recommended waiting period has elapsed, the arrangement is returned to its original upright position, and the pull tab  42  is pulled back to either partially or completely remove the diaphragm  40  depending upon the type of product in the cup and how it will be consumed. For example, a spoon requires more room to access soup within the cup as compared to a beverage which is directly sipped. If the product is a beverage, such as coffee, then the sip lid  30  is snapped over the opened seal, and the beverage is consumed through an aperture  70  (see  FIG. 9 ).  
         [0032]     It will be understood that each of the elements described above, or two or more together, also may find a useful application in other types of constructions differing from the types described above.  
         [0033]     While the invention has been illustrated and described as embodied in a arrangement for and method of selectably changing the temperature of a product, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.  
         [0034]     Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.