GB2055038A - Cup and stack of cups - Google Patents

Abstract

A paper cup, for storing dehydrated food etc. comprises a bottom wall 22 located above the lower tinge 29 of the side wall 21, the side wall 21 being generally frusto- conically shaped, the lower portion adjacent the lower edge being outwardly flared with respect to the upper portion 24, the upper portion 24 having a cone angle of from 3 DEG to 9 DEG and the lower portion having a cone angle smaller by at least 2 DEG . In this way when successive cups 20,20' are stacked with the lower edge of each cup abutting the bottom wall 22 of the next lower cup, the outside surface of the side wall of one cup 20 makes sealing engagement with the inside surface of the next lower cup 20' at 28, right round the periphery of the cups. If the stack is slightly longitudinally compressed e.g. by its shrink wrapping, an efficient sift-proof seal is formed enclosing the food portions contained in each individual cup in the recess below the bottom of the cup next above. <IMAGE>

Description

SPECIFICATION Cup and stack of cups This invention relates to a paper cup and to a stack of such cups suitable, for example, for storing dehydrated food or beverage materials prior to their reconstitution with added liquids.

The prepackaging of dehydrated food or beverage materials, e.g. soup or coffee, between stacked cups provides an efficient and convenient method of storing and dispensing such products prior to reconstitution, usually by the addition of water.

There is a difficulty in finding a suitable design of cups for stacking which will both allow a sufficient quantity of the dried food to be included and provide an adequate seal between successive cups to prevent the food from sifting out.

With plastic cups this problem has been at least partly resolved by, for example, providing an internal shoulder in the cup wall on which the bottom of the next cup seats. With paper cups, though, this design is impractical because of the difficulty of accurately reproducing the shoulder in the fibrous material of the side wall.

With conventional "straight-sided" paper cups, which comprise a frustoconical side wall and a circular bottom wall, the dried food material may initially be apportioned either directly into the cup or into the base recess of the inverted cup. In either case, the seal which contains the food material results from contact of the bottom edge of the side wall of one cup with the inside of the bottom wall of the succeeding cup and this often proves unreliable. The food material may sift out between the side walls resulting in loss of a portion of the measured amount, the sifted material making the outsides of the cups unpleasant in appearance and to handle.

The present invention provides a design for a paper cup in which the conventional straight-sided side wall is replaced by a side wall having an outwardly flared lower portion, which results in an easily-produced cup having improved contact sealing characteristics when stacked.

Thus, according to the present invention there is provided a cup having at least its side wall made of paper and having a bottom wall located above the lower edge of the side wall, the side wall having a generally frustoconical shape but its portion adjacent said lower edge being outwardly flared with respect to the fructocone to an extent such that in a stack of the cups the outside surface of the sidewall of the upper cup of each adjacent pair of cups makes sealing engagement with the inside surface of the lower cup when the upper cup is pushed into the lower cup, so that its said lower edge engages the bottom wall of the lower cup, whereby a sealed compartment is provided between the respective bottom walls of the two cups.

Preferably, the said outwardly flared portion of the side wall is also substantially frustoconical, the difference between the two cone angles being at least 2".

Preferably also, the junction of said outwardly flared portion of the side wall and the remainder of the side wall is substantially at the level of the said bottom wall.

With this shape of cup, similar cups may be stacked, with a portion of dried food material in the bottom of each, the outside of the bottommost part of the side wall of one cup making contact with the inside wall of the succeeding cup just above the bottom wall of that cup. This results in a substantial area of sealing contact, i.e. an interference fit possibly including appreciable resilient distortion, between successive cups in a radial direction.

At the same time the engagement of the lower edge of the upper cup with the bottom wall of the lower cup (at the periphery thereof) provides a positive step when the two cups are pushed together. There is thus no tendency for the two cups to tilt relatively when axial pressure is applied to the stack, e.g. by a shrink wrapping. The cups are firmly located relative to each other, so that the stack is stable. Also, the upper cup cannot be pushed too far into the lower cup; this avoids jamming of the cups in each other due to the axial pressure which is applied.

The cups of the invention can be filled with their portion of dried material when in the normal upright positions (rather than by adding the material into the base of the upturned cup). Then, the lower edge of the upper cup of each pair, will because of its flare, perform a wiping action down the lower part of the inside wall of the lower cup when pushed into the lower cup; this cleans the inside wall of the lower cup, and allows a good seal to be obtained.

Thus according to another aspect of the invention there is provided a stack of cups of the invention having dehydrated material in each cup and means urging the stack in compression axially.

An embodiment of the invention will now be described with reference to the accompanying drawings, wherein: Figure 1 is a general view of a paper cup; Figure 2 shows in section part of two cups of conventional design; Figure 3 shows in section part of two cups according to the invention; Figure 4 is an enlarged view of part of Fig.

2 showing the relevant angles, and Figure 5 shows partly in section a stack of cups according to the invention.

As seen in Fig. 1, the conventional "straight sided" paper cup 10 has a frustoconical side wall 11 and a disc-shaped bottom wall 1 2 which has a peripheral skirt or flange 1 4 around which an extension 11 a of the side wall 11 is folded and crimped to produce the cup. Fig. 2 shows this in enlarged view for a conventional cup.

As shown in Fig. 3, the construction of the cup 20 according to the invention is similar in respect of the attachment of the side wall 21 to the bottom wall 22. In this case, however, the side wall 21 comprises an upper portion 24 and a lower portion 25, both portions 24 and 25 being frustoconical but of different angles with respect to the longitudinal axis through the cup.

Fig. 4 is an enlarged and exaggerated sectional view of the side wall 21 only at the transition 26 between the upper wall portion 24 and the lower wall portion 25. The upper wall portion 24 makes an angle a with the axial direction of the cup and a is preferabiy in the range from 3" to 9 . The lower wall portion 25 makes an angle P with the axial direction and ss is less than a, preferably by at least 2". Thus the lower portion 25 is outwardly flared relative to the cone of the upper portion 24. p may indeed be 0 , in which case the lower wall portion 25 is cylindrical, or less than 0" (i.e. inclined to the axial direction in the direction opposite to that of the angle a), in which case the lower wall portion 25 will be flared outwardly towards the bottom of the cup (i.e. away from the bottom wall 22).

The bottom wall 22 is so disposed that its periphery, from which the flange 34 depends is adjacent the transition 26 between the upper wall portion 24 and the lower wall portion 25. The preferred depth D of the base recess is from 6 to 12 mm.

As seen in Fig. 3, the geometry of the cup is such that when the cup 20 is stacked in a second cup 20', the lowermost part of the lower wall portion 25 of the upper cup 20 contacts the inside of the upper wall portion 24' of the lower cup 20' at 28 producing a contact seal, and possibly to a certain degree resilient distortion of the inner cup, all around the peripheries of the two cups, with a clearance between the upper wall portions 24 and 24' of, in this case 0.25 mm. As can be seen by comparison with Fig. 2 the cups of the invention achieve a contact seal not only at 29, between the bottom of the side wall 21 and the succeeding bottom wall 22', but also as described above around the periphery of the walls at 28 whereas the conventional cups can produce only the former at 1 9.

Fig. 5 shows a stack of cups according to the invention complete with included food portions 40. The contact seal between adjacent cups is maintained by providing a slight compression in the axial direction. This may be provided by the normal packaging if the stack is shrink wrapped or vacuum packed, or even by, for example, string or a rubber band.

Fig. 5 shows a shrink wrapping 42. The depth D of the recess beneath the bottom wall 22 is chosen to provide an adequate chamber for usual amounts of dried food material and the seal between cups is found to be quite adequate to prevent sifting and loss of the contents.

The cups may be made in the conventional way, the bottom seaming operation being accompanied or followed by the wall shaping process in which, for example, a collar having the correctly angled inner surface is positioned around the lower wall of the cup and an element positioned within the cup urges it out towards the collar.

Thus the invention provides a cup suitable for stacking which is easily produced and an efficient container of dried food material.

Claims (8)

1. A cup having at least its side wall made of paper and having a bottom wall located above the lower edge of the side wall, the side wall having a generally frustoconical shape but its portion adjacent said lower edge being outwardly flared with respect to the frustocone to an extent such that in a stack of the cups the outside surface of the sidewall of the upper cup of each adjacent pair of cups makes sealing engagement with the inside surface of the lower cup when the upper cup is pushed into the lower cup, so that its said lower edge engages the bottom wall of the lower cup, whereby a sealed compartment is provided between the respective bottom walls of the two cups.

2. A cup according to claim 1 wherein the said outwardly flared portion of the side wall is also substantially frustoconical, the difference between the two cone angles being at least 2".

3. A cup according to claim 1 or claim 2 wherein the junction of said outwardly flared portion of the side wall and the remainder of the side wall is substantially at the level of the said bottom wall.

4. A cup according to any one of the preceding claims wherein the side wall is generally at an angle in the range 3" to 9" to the vertical axis of the cup.

5. A cup according to any one of the preceding claims wherein the height of said bottom wall above said lower edge of the side wall is in the range 6 to 12 mm.

6. A cup according to any one of the preceding claims wherein the bottom wall is in one piece with a depending skirt which is received in an annular slot formed by an inward and upward fold of the lower edge of the material providing the side wall.

7. A cup substantially as herein described with reference to and as shown in Figs. 2 and 3 of the accompanying drawings.

8. A stack of cups according to any one of the preceding claims wherein each cup is nested inside the next one below and means are provided to exert axial compressive force on the stack.