US 3684123 A
This application discloses cups formed from plastic heat insulating material wherein the bottom of each cup is relatively thin while its side wall is relatively thick. Cups formed in accordance with the invention may be stacked and by virtue of their construction there will be less heat transfer through the side wall than through the bottom whereby the liquid contained in each cup in the stack will be maintained at a desired temperature for relatively long periods of time.
Description (OCR text may contain errors)
[451 Aug. 15, 1972 United States Patent Bridges 154] STACKED INSULATED CUPS 3,491,914 1/1970 Elzey..........................220/9 F FOREIGN PATENTS OR APPLICATIONS  Inventor: John A. Bridges, Nashville, Tenn.
 Assignee: Aladdin Industries,
m 700,408 12/1964 Canada......................220/9 F icago, 1,593,589 6/1970 France F  Filed: Aug. 10, 1970 271,357 5/1927 Great Britain..........220/23.86
[211 App! 62426 Primary Examiner-George E. Lowrance Assistant ExaminerJames R. Garrett  US. Cl. R, 206/4, 220/97 R y Q g Hersh &  Int. Cl. 25/18  Field of Search.......220/9 F, 97 R, 23.83, 23.86;  ABSTRACT This application discloses cups formed from plastic heat insulating material wherein the bottom of each cup is relatively 'thin while its side wall is relatively  References Cited UNITEDSTATESPATENTS thick. Cups formed in accordance with the invention may be stacked and by virtue of their construction there will be less heat transfer through the side wall than through the bottom whereby the liquid contained in each cup in the stack will be maintained at a desired temperature for relatively long periods of time.
2 Claims, 2 Drawing Figures XM XXX 69 5 mo mm a mm 0 1 22M 0 u u. 92 2 u u 2 2 m m 2m Imam numu t mmn Ym 0 e" n nwmm .mmn lm h e o fiwo WCMRSPW 58 2369 2455566 9999999 1111111 6252900 1 11 57 6805 945927 262327 4352577 SWAN-$616,214, 222233 NW J/t I ll llll ll 1 lliil STACKED INSULATED curs BACKGROUND OF THE INVENTION This invention relates generally to insulated liquid holding containers. More specifically, it relates to insulated containers for holding foods intended to be served at optimum temperatures. Insulated cups and the like are known which may be stacked for serving and storage purposes. However, those cups with which I am familiar have either uniform insulation in their bottoms and sides or even have side insulation which is thinner than the bottom insulation. Thus, while such cups or containers may be stacked, they do not retain the liquid contained therein any longer than one would expect from the nature and thickness of the insulation provided.
There may be situations where it is desired to put hot or cold liquids in cups for the purpose of serving individual portions at a later time. Very frequently, these times are as long as two or three hours in the case of hospitals or similar institutions so that cups capable of holding individual portions at desired serving temperatures for this time are desirable.
Therefore, it is an object of this invention to provide a novel stack of insulated cups capable of holding liquids placed therein at a desired temperature for a relatively long period of time.
It is another object of this invention to provide a novel insulated cup which may be placed in a stack of similar cups and which is constructed so as to optimize heat sharing against the liquids contained in each cup.
SUMMARY OF THE INVENTION In one embodiment of this invention the foregoing and other objects are achieved by providing a stack of cups wherein each cup has a bottom and a side wall formed from insulating material and the side walls are relatively thick with respect to the bottom walls so as to permit less heat transfer through the side walls.
BRIEF DESCRIPTION OF THE DRAWING The invention itself is set forth in the claims appended hereto and forming a part of this specification while the structure and mode of functioning of an embodiment thereof may be understood by reference to the detailed description taken in conjunction with the drawing in which:
' FIG. 1 is a side view of a stack of cups in accordance with the invention; and
FIG. 2 is a sectional side view of a stack of cups in accordance with the invention.
DETAILED DESCRIPTION FIG. 1 illustrates a stack of cups 2 wherein each cup is provided with a bottom 4 and a side wall 6. Obviously, a particular shape of the cups is in large part a matter of design and can be varied to reflect aesthetic and practical considerations. In the embodiment illustrated, each cup is provided with a handle 8 but such a handle may or may not be provided as desired.
As is best seen in FIG. 2, each cup has a circumferential shoulder 10 on its bottom while the inner surface 12 of the upper portion of the side wall of each cup is shaped so as to conform to the circumferential shoulder. As may be seen in this figure, when the cups are stacked the circumferential shoulder will engage with the portion 12 to provide structural stability for a stack of cups.
Also, as may be seen in FIG. 2, when the cups are stacked a relativelythin plastic lid 14 may be provided on the top of each cup passing between the shoulder 10 and portion 12 but functioning as a lid associated with each cup when the cups are removed from the stack. The cover may be formed of styrene which is relatively inexpensive material so that it may be disposed of after use while the cups themselves are washable and reusable.
Also, as may be seen in FIG. 2, a stack cover 16 may be provided. The cover 16 may be formed of an insulating material such as styrofoam providing insulation in the vertical direction.
Each cup may be formed by molding in a suitable mold a unitary skin 18 out of a plastic material which is heat resistant and relatively impervious. A suitable material for this purpose is styrene acrylonitrile. The bottom and side walls of each cup are completed by foaming in place heat insulating material. A suitable material is polyurethane foam.
As shown in FIG. 2, each cup is formed so that its side wall 6 is relatively thick with respect to its bottom 4. In this manner, the heat transfer through the side wall is less than the heat transfer through the bottom. Thus, when the cups are stacked and are holding a hot liquid, there will be more heat transfer in the vertical direction between the liquids in the various cups than in the horizontal direction to the environment external of the stack. Consequently, a stack of cups in accordance with the invention will tend to hold a liquid at a desired temperature for a longer period of time than insulated cups having uniform side wall and bottom insulation.
Obviously, various modifications in the materials used and details of configuration may be made and it is intended by the claims to cover all such modifications which fall within their scope.
What is claimed as new and desired to be secured by Letters Patent of the United States is:
1. In a cup the improvement comprising a bottom and a side wall, said bottom and side walls being formed by a heat resistant relatively impervious plastic skin constituting the outer and inner surfaces thereof, the outer and inner surfaces of said side wall being spaced a first relatively great distance apart over the entire height thereof, the outer and inner surfaces of said bottom being spaced a second relatively small distance apart, a foamed heat insulating material filling the space between said outer and inner surfaces, a circumferential shoulder provided between said bottom and said side wall, and wherein the upper portion of said side wall is shaped and dimensioned to engage said circumferential shoulder, and wherein said bottom extends a slight distance below said circumferential shoulder, whereby a plurality of such cups may be stacked with the bottom of one cup extending slightly intoa cup below it in a stack.
2. A stack of insulated liquid holding cups, each having a bottom and a side wall, each bottom and side wall being formed by a heat resistant relatively impervious plastic skin constituting the outer and inner surfaces thereof and a quantity of foamed insulated material 3,684,123 7 3 4 between said inner and outer surfaces wherein the side tion of said side wall is shaped and dimensioned to con- Wall is f y thick Over its entire height While the form to the profile of said circumferential shoulder bottom is relatively thin so as to permit less heat transfer throu said side wall than throu said bottom, each cur? being provided with a circ li mferential 5 wlth the shoulder of the upper cup engaging the shaped shoulder between said bottom and said side wall and porno ofthe cup benea wherein a portion of the inner surface of the upper porwhereby one cup may be stacked on top of another cup