WO1998036978A2

WO1998036978A2 - An open container or cup of which one half is folded into the other

Info

Publication number: WO1998036978A2
Application number: PCT/DK1998/000066
Authority: WO
Inventors: Knud Vinther
Original assignee: NEWMATE APS
Current assignee: NEWMATE APS
Priority date: 1997-02-19
Filing date: 1998-02-19
Publication date: 1998-08-27
Anticipated expiration: 1999-08-19
Also published as: WO1998036978A3; DK17497A

Abstract

An open container or cup of a tight material, which cup is collapsible after use and is formed with either a lateral surface sloping outwards and upwards from the bottom towards the opening, or with a straight tubular lateral surface, which by saddle folding of the bottom surface and with a corresponding folding of the cup wall surface into two mainly mirror-congruent halves abutting against each other may be brought into a state for the cup that is in principle plane. The first lateral section of the rim (K) of the open cup between the points (M, N) has a permanently reinforced shape which preferably consists of a turn-down or solid bead, while the second lateral section and its rim (L) in the open position of the cup is distended in an elastic and flexible arch, the strength of which along the sections of the rim is reduced at the points (O, P), or the rim may be made without a bead as said secont lateral section in the collapsed state of the cup bears against the first lateral section with an elastic force which approximately corresponds to the elastic force in the distended arch (L) of the lateral section in the open position of the cup.

Description

AN OPEN CONTAINER OR CUP OF WHICH ONE HALF IS FOLDED INTO THE OTHER

The invention relates to an open container or a cup which is collapsible and made of a tight, flexible material which is resistant to absorption or seepage of the content of the cup, which material may be waxed or lacquered cardboard, cardboard foiled with a thermoplastic film, or the material may consist of pure thermoplastic like polyethylene or polypropylene. The cup is formed with a lateral surface sloping outwards and upwards from the bottom towards the opening, which is known from a paper cup accord- ing to an older US Patent No. 1,738,779 together with a surface-treated cardboard cup with polygonal lateral sections sloping outwards and a polygonal bottom according to PCT Publication WO 96/27527. According to the Danish Patent No. 170.503, there is also known a cup with a straight tubular cup wall surface, as all these cups are folding by saddle folding of differently configured bottom surfaces and by a folding of the cup wall surface adapted thereto, which cup wall surface in the open configuration of the cup may consist of two or more lateral sections, but which in the collapsed configuration consists of two mainly mirror-congruent halves. Cups of the said kinds are preferably made of cardboard based materials and they all have a design based or application dependent collapsed shape before they are put into use as an open cup. The cup may furthermore be provided with a removable lid fitting the opening at the top of the open cup. Cups of the said kinds are preferably intended to be discarded after use or to be returned for recycling, granulating, remelting or incineration depending on the kind of the used material of manufacture.

Cups with a permanently open form are often designed with a conical cup wall surface which makes it possible to store the cups within each other. Furthermore, there are reasons of manufacture that cause the cup wall surface preferably to have a slightly conical form so that it may more easily be released from the mould in which or on which the cup is made. Foldable cups with a straight tubular cup wall surface cannot be stacked inside each other while other foldable cups may well be stacked after the closed cups are folded up. Compared to a cup with a permanently non-foldable form having a conical cup wall surface, the foldable cups fit badly into an automated indus- trial filling system where the cups are filled with products like paint or food-stuffs. • Cups having been folded before use are time-consuming to open in order to make them stackable as well as the form stability, specially in plastic cups, will make it difficult to achieve a uniform and precise full opening of the cups, which is necessary when the cups are stacked inside each other because of the used filling technique. Because of the bad form stability in foldable cups made of cardboard based material, such cups are not suitable for opening and stacking and for transport and long-term storage of the content. The form stability in cardboard is further impaired by the cups already having been folded before use. If such a cup also has polygonal lateral sections in the cup wall surface, this feature will further depreciate the stability and uniformity of the cup as well as the edged sections will make it difficult to stack the cups and to provide these with a lid. The problem would further reappear when the user had to take off and put on the lid as the polygonal side surfaces of the cup could be displaced with the result that the content of the cup would flow out over the rim of the cup. Conversely, the collapsed shape of the folded cups is suitable when the cup is emptied of its content and has to be discarded or returned for recycling or incineration. Plastic cups having a great form stability may therefore be collapsed with great advantage if there is used a technique taking account of the form stability in such a way that the folding mechanism does not have any influence on the form of the open cup, just as the form stability of the open cup has to be overcome in the closed and collapsed state of the cup.

If the right technique is utilised, the collapsed, airless cup will make it possible for the users to store the empty packing in many different sizes and shapes in very little space, which in practice will be garbage bags. Even if no actual sorting takes place, the collapsed cups will also take up less space together with the other household waste. If a sorting takes place, it will likewise be easier to collect and transport the airless plastic packings to central collecting spots where the waste is possibly moved and pressed into bales. Presently, the general attitude is that plastic waste shall not end on refuse dumps where the plastic is composed very slowly, but instead should be used as fuel as plastic has a heating value at the level of oil. In several countries, among them in Switzerland, where household plastic waste is in fact used as fuel for the cement industry, they are far on in practise.

Another important problem in the development and making of moulded, collapsible plastic cups is the placing of the folding lines and the relationship between the side of the cup wall surface sloping outwards and the triangles marked with folding lines at the transition to the quadratic or rectangular bottom of a cup. It is not possible to make a cup without a mould, and because the placing of the folding lines and the dimensioning of the said triangles are not known from the outset, it is not possible to integrate these lines into the mould. Therefore it is necessary to make a mould without integrating the folding lines. The finished cup from a mould is subsequently to be folded whereby folding lines are formed, appearing as deformations in the material. The cup is then folded open again and put in the mould whereby you can place the folding lines on the mould as we may be speaking of either an injection mould or a mould for vac- uum forming or blowing of thermoplastic sheets or webs. Such moulds are very costly, and it is therefore problematic that several moulds for making prototype cups have to be made. If the folding lines are not put very precisely on the cup, a plastic cup will not be folded properly tight just as the cup will have a tendency to revert to the open form because of the great form stability of the plastic. Therefore it will be diffi- cult to achieve the preference of the users of a cup not working properly at the collapsing, just as a cup which has been folded before use may appear unstable and may cause waste of the content of the cup by external pressure actions on the cup which during unlucky circumstances could cause an uhdesired folding or collapsing of the cup.

The invention makes it possible to combine the effects of a permanently open and stable cup with the effects of a corresponding collapsible cup.

The cup according to the invention is provided with a partly foldable opening at the top, where one side of the cup wall surface together with one half of the opening has a permanently stable form, while the other side together with the other half of the opening is flexible and may be folded into the first-mentioned half under the action of an elastic force making the two halves bear tightly against each other under the action ^■ of a permanent, elastic force. The folding at the opening of the cup takes place independently of the folding bottom, which is known per se, and the effect is achieved by reinforcing one half of the opening with a turn-down or solid bead at the rim of the opening, as this half of the opening may be further reinforced with a stay loosely or permanently fastened thereto in plane with the rim or just under this. The rim of the other half of the opening is made flexible by removing or discontinuing the rim or the bead of the cup at points, which weakens the rigid shape of the rim so sufficiently that this other half of the opening may be pressed inwards into the cup once the bottom is folded, whereby the other half of the cup is turned opposite and bears against the first half of the cup under the action of a constant spring action corresponding to the spring action of the said second half of the open cup. The second half of the opening may also be made without a bead which makes it more easy to overcome the spring forces if the cup is preferably of a kind used in open and collapsed state several times or if the rim of the other half of the cup is curved or has a semi-circular form.

In second suitable embodiment of the cup according to the invention the previously mentioned stay at the rim of the first half of the opening is hinged over the two ends of the stay to the cup at the top of the two folding lines of the cup wall surface, and the stay is thus used also as a carrying handle. The stay thus serves a dual purpose. When the cup is standing on the base and when an otherwise shape stabilising lid for the cup is demounted, the stay assists in making the rim at the opening of the cup at the first half of the opening more rigid and stable when the stay is attached loosely at the rim of the cup with a clip device, or with another holding mechanism known per se. When the cup is lifted up from the base by means of the carrying handle, the weight of the cup itself with content will cause the carrying handle to be pressed inwards against the cup wall surface with the said weight which contributes to increase the open shape of the cup. If the carrying handle had instead been fastened to the cup transversely to its correct position, the carrying handle would have a tendency instead to fold the open- ing of the cup together. If the lid of the cup is mounted when the cup is lifted from the base by means of the carrying handle, there is achieved an optimum stabilisation of the opened form of the cup during manual transport thereof. According to an especially suitable embodiment for the cup according to the invention, it is shaped with a previously mentioned stay and carrying handle which may be de-hinged over the ends as the lugs of the cup for hinging the handle are formed with slits through which the slightly open eyelets of the carrying handle may be detached.

If stay and carrying handle are made from plastic together with the cup, the carrying handle may instead be cut off in the hinge notch. Thereby the cup achieves the same advantages in use as the previously mentioned cup with a stay and carrying handle that are fixed on the cup while the handle is now detached when the cup is discarded for incineration or remelting. When the carrying handle is made from metal, this part of the cup may be sorted out for itself together with other metal waste. However, when the carrying handle is made of plastic like the cup, the handle may be cut off at least at one end of the cup whereby this is irrevocably discarded. WTien the carrying handle is demounted, it will be easier to press the collapsed cup into bales together with other plastic waste as the permanent form of the first half of the cup is weakened when the stay or the handle is demounted.

According to a preferred embodiment for the cup according to the invention, this is made by moulding with thermoplastic outside on or inside in the mould. By this method of manufacture it is possible to mould the folding lines of the cup, either as U- or V-shaped ditches in the material or like semi-open beads or as double line thickenings with folding lines between these line thickenings. The cup is not folded before use and it is stackable with a cup wall surface extending upwards and outwards from the bottom and towards the opening. Such a cup has technical specifications at a level with a corresponding cup used in a permanently open form as the cups are uniform, stable, and with good bending strength as well as the stacked cups may be able to resist the pressure from the stack. Therefore such cups are suitable for use in automatic filling machines. When the cup is collapsed after use, this will take place according to the moulded folding lines in the cup, whereby the empty air volume of the cup is re- duced completely. The environmental and consumer servicing properties of the cup are evident while at the same time, for the packing and commodities branch, the cup does not imply changes in relation to the use of a cup with a permanently open form. The cup contributes to achieving a better economy in collecting and sorting of waste for recycling or incineration as well as the political taxes on non-returnable materials are avoided.

By a very precise embodiment for the cup which is also an indicated method for making the mould for the cup according to the invention, this is provided with a saddle foldable quadratic or rectangular bottom of the kind where two of the opposite edges of the bottom form base lines in the attached isosceles triangles which are marked in the cup wall surface along folding lines as the vertex angles of the isosceles triangles each are less than 90°. Hereby the cup wall surface becomes outwards sloping from the bottom and upwards against the opening of the cup which now may be expressed by the equation 90° minus A = E as E = F in the closed state of the cup appearing from the drawing. The equation or formula shows surprisingly that there is a connection between (1) the angle of the downwards sloping cup wall surface against the perpendicular to the bottom surface and the magnitude of the vertex angles (2) of the previously mentioned isosceles triangles. Thus, if you know one of the quantities (1) or (2) it will be possible quite accurately to calculate and place the folding lines and angles of the cup along folding lines for the moulded plastic cup without the cup and the mould thereto having to be made at first without folding lines according to which the cup otherwise had to be folded whereby the folding lines may be marked by deformation of the cup wall surface. This realisation results in that already from the start you may place the folding lines on the mould for quite different cups. As such moulds -ire rather costly and because you otherwise cannot make a natural cup without moulding, development costs are saved when already the first mould may be produced as the final mould for serial production of the cup. Also, hereby there is achieved a very much greater degree of freedom for planning and performing function and design when there is economic security for the functioning of the first mould.

The invention will be explained further in the following with reference to the drawing wherein Fig. 1 shows a cup according to the invention as the cup has two lateral sections • distended in mirror-congruent arches as the rim of the first arched lateral section has a permanently rigid form while the rim of the other lateral section has a flexible form, and Fig. 2 shows a cup according to Figure 1 , but in a collapsed position as the two lateral sections bear against each other and follow the form of the arched section having a permanently rigid form, and Fig. 3 shows a cup according to the invention, as the cup is shown with a mounted lid and is formed with a stay along the rim of the first lateral section having a permanently rigid form, which stay is loosely attached at the rim and has hinged parts over the ends and thus also may be carrying handle for the cup, and Fig. 4 shows a cup according to the invention as the stay which also is a carrying handle for the cup may be detached over the ends, and Fig. 5 shows a cup according to the invention as the cup is moulded in transparent plastic and has not been folded before use as well as the folding lines and angles of the cup marked with folding lines are calculated and placed on the cup as well as on the mould thereto according to an equation or a formula, and Fig. 6 shows a collapsed cup according to the invention as the Figure shows the connection between the angles E and F according to the formula for making cup and mould.

Figure 1 show a cup in an opaque thermoplastic of the kind used for butter and dairy products among others. The two lateral sections of the cup are distended in mirror- congruent arch shaped and parallel sections. The shown bead is discontinued on a part of its turn-down where the two lateral sections are meeting over the ends of the cup in the points M and N, but as the bead is not completely discontinued the points M and N work like springs when the cup is folded, whereby the bead also is contributing to create the open form of the cup. The rim K of the first lateral section has a permanently rigid form between the points M and N as the bead instead could be injection moulded solid or could contain a solid stay that could be pushed up under the bead and thus would contribute to make the rim of the lateral section even more rigid. The second lateral section L between the points M and N has a bead that is discontinued in the points O and P. Hereby it is possible to push the lateral section L towards the lateral section K when the bottom of the cup is folded together as the lateral section L then will bend in the points O and P and the section L may hereby be brought to bear against the inner side of the lateral section K.

In Figure 2 the cup is seen according to Figure 1, but in collapsed state. It appears from the Figure that the lateral section at the rim K has kept its permanently rigid form while the lateral section at the rim L now bears against the inner side of the lateral section at the rim K. Hereby the bead is squeezed in the points O and P while the bead at the points M and N is stretched around the cup wall surface at the rim thereof.

In Figure 3, there is seen a cup in an opaque, injection moulded thermoplastic as the cup is shown closed with a lid. The lid as well as the stay R which also is a carrying handle R2 are contributing to give the open cup a stable and stiff form. The stay and the handle R are moulded in one piece with the cup in the hinge points S and T. The hinged parts or carrying handle is seen enlarged in V while the notch itself for the pivot joint of the hinge is seen enlarged in X. This mechanism makes the carrying handle pivotable over the cup as the carrying handle may be fastened as stay for the lateral section with the permanently rigid form with a clip or spring lock device, which is either at the rim or at the top on the lateral section of the cup. When the handle is cut off at the notch X, the cup is irrevocably discarded as well as the cup is more easily squeezed together with other plastic waste into bales or like forms of storage when the stay and the handle R are cut off.

In Figure 4, there is seen a cup in transparent injection moulded thermoplastic. The stay and the carrying handle R are shown in their upright position as carrying handle pivoting in the hinge joints S and T as you see the slightly open eyelets of the carrying handle which may be detached and mounted in the slits in S and T. The carrying handle may be swung down over the bead at the rim of one of the two lateral sections. The carrying handle R is pressed past the bead K and thereby bears against the under side of the bead which thus functions as a spring lock for the position of the carrying handle as stay for the cup half, whereby the rim thereof gets a permanently rigid form as long as the stay and handle are mounted hereto.

In Figure 5, there is seen a cup in transparent, injection moulded or vacuum moulded thermoplastic. The folding lines of the cup at the saddle folding bottom and the cup wall surface sloping outwards from the bottom and up to the opening have not been folded before the use of the cup and the cup therefore has the same technical properties of use as a cup with a permanently open form with regard to stability, position, bending strength, and stackability. The cup is made with a mould which already from the beginning has built-in markings for embossing the course of the folding lines in the moulded cup. It is possible to place these course of markings for the folding lines by means of the formula or equation 90° minus A (80°) = E (10°). In the present case it was desired with a slope of 5° of the outwards sloping cup wall surface with the normal to the bottom surface, and the folding lines of the mould at the bottom at the isosceles triangles could hereafter be dimensioned according to the said formula.

In Figure 6, there is seen a collapsed cup showing the connection between folding lines and angles in a cup which is only folded together after use and which is con- structed with a mould which also is constructed on the basis of the formula 90° minus

A = E, as E = F in the closed position of the cup. From the Figure it is seen that the angle E of 10° = the angle F.

Claims

1. An open container or cup which is tight and may be made of a material resistant against absorption or seepage of the content of the cup, which cup is collapsible and formed with either a lateral surface sloping outwards and upwards from the bottom towards the opening or with a straight tubular lateral surface, which by saddle folding of the bottom surface and by a corresponding folding of the cup wall surface into two mainly mirror-congruent halves abutting against each other may be brought into a state for the cup that is in principle plane, and if the cup is not moulded but made of a plane material as cardboard foiled with plastic film, the cup is brought into a wholly or partly plane state before use, c h a r a c t e r i s e d in that the first lateral section of the rim (K) of the cup between the points (M, N) has a permanently reinforced shape which preferably consists of a turn-down or solid bead, or by a stay loosely or permanently fastened at the rim of the cup and following the shape of the rim and thereby constitutes or reinforces the said bead, while the second lateral section and its rim (L) in the open position of the cup is distended in an elastic and flexible arch or polygonal curvature, where its strength along the sections of the rim is reduced at the points (O, P), which weakening may be achieved by removing or discontinuing the rim or bead of the cup at the said points, or the rim may be made without a bead as said second lateral section in the collapsed state of the cup bears against the first lateral section with an elastic force which approximately corresponds to the elastic force in the distended arch (L) of the lateral section in the open position of the cup.

2. A cup according to claim 1, c h a r a c t e r i s e d in that the stay ( R ) attached at the rim of the cup is hinged (S, T) above the two ends at the top of the two folding lines of the wall surface of the cup and thus also forms a carrying handle (R2).

3. A cup according to claim 2, c h a r a c t e r i s e d in that the stay or the carrying handle may be detached or cut off at one or both ends at the transition to the cup (S, T, X).

4. A cup according to claim 1, 2, and 3, characterised in that the cup is moulded and made of a thermoplastic material and that the folding lines of the cup is moulded into the material in a way known per se as the cup is not folded along the folding lines previous to the use thereof.

5. A cup according to claim 1, 2, 3, and 4, characterised in that the angles of the cup at the folding lines and the corresponding folding lines and angles on the mould for manufacturing the cup which is moulded inside or outside of it may be expressed by the equation 90° minus A = EasE = Finthe collapsed state of the cup, in that the application of this equation or formula determines that the bottom of the cup is quadratic or rectangular and of the kind where two of the opposite edges form base lines in the attached isosceles triangles which are marked in the cup and on the manufacturing mould thereto along folding lines, as the vertex angles (A) of said isosceles triangles each are less than 90°.