DE29709220U1 - Container closure and selected containers - Google Patents

Description

Container closure and selected containers

The invention relates to a closure for the releasable closure of containers made of foldable material, containers suitable for this purpose with devices for fixing objects accommodated in the containers, in particular made of cardboard or materials having equivalent mechanical properties that are suitable for repeated use.

It is known to provide three-dimensional packaging, which is designed as folding cards, folders or cardboard boxes, with appropriate closures, which are formed into physical structures by inserting corresponding latches into suitable insertion openings, such as slots. Packaging of this type is largely disposable packaging and is unfolded after the object to be packaged has been removed and is not reused in the same way. The closures used in this packaging wear out quickly and have a very limited lifespan, which makes frequent reuse very difficult. The folds of the closure tabs or acute-angled cutouts weaken the material and make it unsuitable for mechanical stress. If opened carelessly, the closure is damaged and rendered unusable. Due to the concealed arrangement of the closure, it is recognized too late how the closure mechanism is designed and how it is suitable for opening. An ordinary folding box is shown as an example. The tuck-in flap used here functions partly as a force fit and partly as a form fit, the tuck-in flap is folded and cut at its bending points. This measure creates a vulnerable cross-section and indicates that the material is at risk of breaking. When opened, the form fit is strengthened and the flap is torn off. If the corner is torn off, a closure can no longer be guaranteed and the packaging is no longer suitable for further use.

The invention is based on the object of creating a closure for the releasable closure of containers made of foldable material as well as containers suitable for this purpose with devices for fixing objects accommodated therein, in particular made of cardboard or material with similar mechanical properties that are suitable for repeated use, which allows the containers to be opened and closed again without considerable effort and with simple handling by operating the closure, or to releasably attach additional devices to the containers.

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According to the invention, the object is achieved in that the closure has a cover layer and an intermediate layer. The cover layer has bars on its front edge in the area of grooves. The bars are designed in such a way that they interact with inserts that are incorporated in the intermediate layers near the folded edges of the container. The spacing of the inserts is designed in such a way that the bars can be inserted into the inserts until the edges of the grooves rest against the inserts. This process is completed when the projected length of the outer edges of the cover layer has its greatest extent. The cover and intermediate layers are in a closing functional position and the contact points of the grooves in the inserts are congruent in their spacing with the inner side edges of the inserts connected to them. The design and position of the bars, in conjunction with their grooves and the slots in the intermediate layer, is advantageous because the stretched edge of the bars in the slot is in a complete holding position. The front edge of the cover layer, in the area between the bars, is not pre-stressed and lies flat and without gaps on the intermediate layer. This has the advantage that the material is brought into an effective position without tension and without pressure between the bars and the slot. If the bars are to be made to slide out of the slots to open the container, then the edge of the cover layer is lifted off the intermediate layer. Pragmatically, opening is carried out by applying counter-pressure against the grooves in the cover layer. The projected length of the edge on the intermediate layer is shortened and the bending of the cover layer upwards is continued until the bars have slid out of the slots. If the cover layer rests completely on the intermediate layer in the area of its front edge between the bars, it requires some skill to move the cover layer into a raised position that allows the bars to be pulled out of the slots if pressure is not to be exerted on the grooves to open them. The invention is designed in such a way that the distance between the slots on the intermediate layer is slightly shortened in relation to the edges of the grooves in the area of the bars. The distance between the slots is smaller than the distance between the contact points of the grooves when the bars are pushed in. This gives the edge of the cover layer a pre-tension and lifts off the intermediate layer in a slightly curved form. The design of the invention now allows the already slightly curved edge to be grasped and lifted so that the bars can slide out of the slots. Furthermore, the force connection between the insert and the bolt is increased by the pressure of the edges and the form connection between the bolt and

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The insert is better preserved. The expert will of course read that the pre-tension between the bars must not be so great that the pressure causes mechanical damage or deformation of the contours of the closures. Therefore, in the sense of the invention, it is an advantageous design if the distances between the inserts from each other compared to the contact points of the bars are reduced by between 1 and 3 mm. From the illustrations it can be seen that the closure according to the invention can be used for a wide variety of types of containers. The containers can be given a wide variety of shapes and a versatile use. In the advantageous sense, according to the invention, the closures are arranged on a folding card-like container. The explanation is clearly given on an unfolded container. The cover layer with the bars is connected to a base part via a parallel pair of folds, opposite which the intermediate layer with the inserts is connected. A pair of fold edges is arranged in the same way between the base part and the intermediate layer. In the folded position, the intermediate layer first covers the base part, over which the cover layer comes to rest. The bars are now in an overlapping position above the inserts. The pairs of fold edges are designed so that each pair runs parallel at a variable but close distance and in the position that when the container is folded up, the insertion of flat three-dimensional bodies is permitted. If the three-dimensional bodies exceed their static friction in the folding card due to their higher weight, they slide out of the card that is open at the side. According to the invention, the solution is advantageous in that the base part between the immediately adjacent fold edges has a smaller dimension than the body to be inserted. It is helpful to have slots arranged between the parallel folding edges through which the bodies can slide with their parts protruding from the base. They protrude from the folding card with a small size, are locked in the slots and can therefore be transported safely. The objects can be rotationally symmetrical and polygonal. With a rotationally symmetrical shape of the bodies, the slots lie opposite each other on the center axis of the container and their longitudinal dimensions are dimensioned in such a way that the bodies are held in place without play. With polygonally shaped bodies, it is advantageous according to the invention if the slots are offset from the center axis of the container and thus a sensible arrangement of the polygonal bodies between the folding edges is achieved.

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If the folding cards are closed, as already shown above, then the attached bodies are securely locked in place against at least three types of movement and are largely protected against damage of all kinds.

The use of the closures on mostly flat containers, as shown in the invention, is not intended to limit the applicability of the type of closure according to the invention. Thus, when using the solution according to the invention, it is advantageously possible to use the invention on containers that have a cubic shape and are intended to be openable on at least one side. It can therefore be declared advantageous that the closures according to the invention make it possible to open cubic containers from at least three sides. According to the invention, one closure is arranged on each of the opposite sides and one closure is arranged between them. Such an arrangement of the closures allows the containers to be filled and emptied from above and below as well as from the sides. From the further representations of the embodiment of the solution according to the invention, the person skilled in the art will see that the inventive allocation of the closure elements, intermediate and cover layer, latch and insert, has not been changed even in containers of this complicated type.

The design possibilities of the invention are manifold and can also be used for closing flat boxes. In these boxes, the upper edge is extended and drawn over the upper surface in the form of a tab. Following the principle of the inventive design of the closure, the cover surface is formed here by the extended flap with its latches, with the inserts being molded into the underlying surface of the box. The position of the inserts is adapted to the distances between the latches on the flap, with the grooves being larger in the usable form to form a pleasing flap contour and to facilitate handling. However, the dimensions of the latches with their inserts are adapted to the application form. Thus, when using the latches in the inventive closure design, larger dimensions can also arise if the closure also has to absorb tensile and shear forces at the same time, as was selected for a designed application of the invention as a briefcase or office folder. The inventive application of the invention to a briefcase advantageously indicates the reinforcement of the edge area between the bars by using a reinforcing element that extends parallel to the edge between the bars, including them. The reinforcing element has restoring properties and can advantageously be made of spring steel. According to the invention, it is

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This is useful if the closure elements are used as holding devices for containers that are hung on the walls of these containers with their latches inserted into the slots and can be used to hold accompanying or information papers. As an information carrier for accompanying the containers during transport, it is also advantageous to insert cards into the walls of the containers. The cards have latches that are inserted into slots that are custom-made for this purpose in the container walls. In a further embodiment of the invention, it is very advantageous to provide these cards with carrier elements for writing utensils such as ballpoint pens and pencils. The elements can preferably be used on bags and folders for personal and professional use. The inventive principle of arranging latches in the cover layer and slots in the intermediate layer has also been maintained for the elements to be hung and for the cards. The use of the closure serves as a holding system and does not lead to any deviation from the solution according to the invention, since it contains all the basic elements of the invention.

The invention will be explained in more detail using an embodiment. The accompanying drawing shows:

The container as a folding envelope with the closure closed, The container according to Fig. 1 in the open state, The container according to Fig. 1 and 2 in the unfolded state with a CD inserted The container according to Fig. 3 with a diskette inserted, A cubic container with multiple closures in the partially unfolded state,

The container according to Fig. 5 in the completely closed state, The container according to Fig. 5 and 6 as unfolded and in the completely unfolded state,

Fig. 8: A container designed as a flat cardboard box that can be opened at its upper edge,

Fig. 9: The closure arrangement according to the embodiment of Fig. 8, Fig. 10: A container design in the form of a bag, Fig. 10a,b: A clip card, hung in a briefcase with loops, Fig. 11: The container design in the form of a flat folder,

Fig 12: The closure arrangement, modified for a container as a hanging closure.

Fig. 1: Fig. 2: Fig. 3: Fig. 4: Fig. 5: Fig. 6: Fig. 7:

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Fig. 1 shows a closure arrangement of a container in the form of a folding card 1 in the closed state. Latches 3 of the closure are inserted into slots 4, which are incorporated in the intermediate layer 6 of the folding card 1 and close the folding card 1.

The slight curvature of the edge 5 of the cover layer 2, which can be seen in the illustration, is also indicated after the closing process has been completed. When the folding card 1 is closed and the latches 3 are fully inserted into the slots 4, the edge 5 is still slightly curved above the intermediate layer 6. The slight curvature of the edge 5 ensures that the closure is constantly secured in its closed state, since the latches 3 are constantly locked in the slots 4 under slight pressure. Only when the folding card 1 is to be opened is the cover layer 2 raised in the area of the edge 5. This removes the pre-tension, increases the curvature of the cover layer 2 in the area of the edge 5 and reduces the projected length between the bars 3 so that the outer edges of the bars 3 slide out of the slots 4 or, in the reverse, the closing process, can be easily and safely brought over the slots 4 in order to enable the bars 3 to be easily inserted into them, as shown for the start of an opening process, which is completed in the arrangement according to Fig. 2.

Fig. 2 shows the folding card 1 in the open position, just as it is brought into a closed position shortly before closing with the latches 3 over the slots 4. Here, the latches 3 are brought into an inserted position with their outer ends by bending the edge 5, produced by opposing pressure on the grooves 12, of the cover layer 2 over the slots 4 in the intermediate layer 6. By inserting the latches 3 into the slots 4, an uncomplicated, repeatable opening and closing of the folding card 1 is possible. The simplicity of the closing process is already evident in the fact that merely a curvature of the cover layer 2 at the edge 5 shortens the projected line between the slots 4 so that the outer edges of the bars 3 on the cover layer 2 are brought into an active position above the slots 4, inserted into this position and moved into a secure closing position by light pressure on the cover layer 2 in the area of the edge 5. The design of the container as a folding card 1 in the manner of an envelope allows the secure protection of letters, cards and other flexible objects with a flat shape, which are safely placed in the folded envelope-shaped container and are protectively enclosed by it.

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Fig. 3 shows the container according to the embodiments of Figs. 1 and 2 in an unfolded view. As already explained for Figs. 1 and 2, the design can be used to insert and wrap a variety of flat objects. For flat objects whose own weight does not ensure that they are held in the container by friction, slots 11;1Γ are arranged between the folded edges 8;8'9;9' of the folding card 1. The unfolded position shows in detail the closure design and the arrangement of its elements in the unfolded body of the folding card 1. When unfolded, the folding card 1 has a rectangular extension. It is divided into almost three equal parts, with the division being marked by pairs of parallel folded edges 8;8';9;9'. The slots 11;II ¹ for holding larger flat structures of different shapes are incorporated into the folded edges 8;8';9;9'. The division is designed in such a way that the size of the base surface 7 in its extension to the fold edges 8;9 is smaller than the extension of the object to be inserted. As Fig. 3 shows, a compact disk - CD - 10 was selected as the object to be wrapped, the diameter of which has a greater extension than the distance between the fold edges 8;9. Since the corresponding slots 11;1&Ggr; are arranged in the fold edges 8;8';9;9', parts of the CD 10 protruding over the fold edges 8;8';9;9' can be inserted into the slots 11;1&Ggr;. They cover the base surface 7, protruding from the folding card 1. When the folding card 1 is folded, as shown in Fig. 1, complete positional security for all three possible directions of movement of the CD 10 is guaranteed. If the body to be inserted deviates from a rotationally symmetrical shape into a square or cuboid or polygonal shape, suitable opposite extreme points are selected which are arranged in slots 11;1Γ of the folded edges 8;9. As shown in Fig. 4 when using a disk 13, the slots 11;1Γ on the folded edges 8;9 can be arranged offset from one another in a variety of ways to secure the inserted object 10;13.
When looking at Figures 3 and 4 with the slots 11;1&Ggr; between the fold edges 8;8';9;9', it can be seen that the bars 3 do not exceed the contours of the folding card 1, but remain within their defined contours. The bars 3 are formed by making grooves 12 in the interior of the cover layer 2, the grooves of which allow the bars 3 to be formed. The bars 3 protrude outwards, symmetrically opposite each other on the side edges. For better handling, they are provided with radially extending outer edges, which allow easy sliding into the respective insert 4, which is on the intermediate layer 6 in

Erich and Nern, Patent Attorneys GBM 1547B - 8 -

the area that is close to the folding edge 8. The knowledgeable observer, knowing the configuration of the container and its original closure design, after looking at Figures 1 and 2, will now see the advantage of the container design with its new closure and the locking options for objects to be inserted as being obviously advantageous. The development with the markings for the inserted objects and their locking options reveal the inventive value of the design. The now fully extended length of the edge 5 shows, when looking closely at the position of the slots 4 for the bolts 3, that the part of the bolt 3 that runs from the rounded area into the area of the groove 12, in its section running parallel to the edge 5, enables a secure, durable closure of the container even when tensile forces are applied, because the possible pre-tensioning of the edge 5 ensures that the bolts 3 are held securely in the slots 4 in the area of the parallel edges 28. The slot-shaped design of the slots 4 ensures sufficiently secure friction of the horizontal edge 28 in the boundary of the bolt 3 and thus that the bolt 3 slides out of the slot 4. Due to the type of use chosen, the developments in Fig. 3 and 4 are similar.

It is obvious to the expert reading this that the material selected must have the necessary mechanical properties. Cardboard or cardboard-like materials are used as far as possible. Figs. 5 and 6 show a container in a cuboid shape. Fig. 5 shows the container in a partially opened form. The opposite open sides 14; 16 allow the container to be easily filled with objects of various shapes. The container can be opened and closed separately on three sides, as shown in Figs. 5 and 6. To enable this process, three sides 14; 16; 17 of the container are provided with closures designed according to the invention, as shown in connection with Figs. 1 and 2 and incorporated into the surfaces of the sides 14; 16; 17. It is of course necessary that the sides 14; 16; 17 are double-walled and consist of cover and intermediate layers to enable the formation and positioning of bars 3 and inserts 4 relative to one another, which allow the containers to be securely closed. To ensure that all sides of the container are clearly fixed in position, tabs 29 are provided on the sides 14; 16; 17 to be closed. For handling reasons, the tabs 29 are rounded on their outer contours and thus allow them to be easily folded into the container body.

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Fig. 7 shows a development of the container according to Figs. 5 and 6. The development once again illustrates the already indicated closure option of the container. Longitudinal fold edges 20 and transverse fold edges 8 are continuously defined from the image plane, which enable the container to be contoured when folded. The fold edges 8; 20 allow the sides 14; 15; 16; 17; 18; 19 to be folded in precisely. The development shows that the inserts 4 are incorporated in the intermediate layers 6 and the bars 3 in the cover layers 2. The tabs 29 are arranged on the fold edges 20, in the area of the surfaces that carry the inserts 4, and are attached according to their foldability requirements. Together with Fig. 5 and 6, the development of the cuboid container shows that the container can be opened and closed in a variety of ways, either on one, two or three sides simultaneously or one after the other. Of course, the cuboid container can be of any size. The decisive factor is its pragmatic handling, which depends largely on the materials and their mechanical properties.
Thus, according to Figs. 8 and 9, the closure according to the invention is selected for a flat, cuboid-shaped container which can be opened at its narrow top. The top is extended in the form of a flap 23 and extends over the surface of the box. On the edge 5 of the flap 23, latches 3 typical for the closure are arranged, which are arranged in slots 4, closing the box 21 on its top. For better handling, a handle 22 can be attached between the latches 3, on the edge 5 of the flap 23. The handle 22 allows an uncomplicated arching of the flap 23 in the area of the edge 5 and thus a safe, uncomplicated sliding out of the latches 3 from the slots 4 when opening and a slight arching of the flap 5 stretched before closing in order to shorten the projected line between the latches 3 so that they can be safely inserted into the slots 4.
Fig. 10 and 10a show the design of a pocket 24 with the closure according to the embodiment shown in the previous figures. The pocket 24 is provided with a flap 25 which overlaps the pocket body and allows the closure to be arranged in its lower end. In the area of the upper edge 5, a handle 22 is provided which interacts with a reinforcing rail which spans the back of the pocket to form a contour. In carrying out the invention, the reinforcement can be made from a light spring steel rail. The latches 3 of the flap 25 engage in slots 4 of the intermediate layer 6 of the pocket 24. As already shown, the shape of the latches 3, the pre-tensioning of the edge 5 and

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the slot-shaped design of the inserts 4 in the intermediate layer 6 of the pocket 24 ensures that the flap 25 is securely locked. Fig. 10a shows the pocket according to Fig. 10 in a basically similar representation with the variation that a reinforcing element 30 is arranged parallel to the edge 5 of the flap 25. The reinforcing element 30 spans the flap 25 in the area of the edge 5 up to the latches 3. The reinforcing element 30 can be an elastic spring steel element which, with high dimensional stability, allows for easy bending and thus allows the inserts 4 to be easily fixed by the latches 3 and the holder therein. The design according to Fig. 10a is to be preferred above all when the latches 3 are loaded with tensile and shear forces. Fig. 10a clearly shows the arrangement of a hanging element 32. The inserts 4 and the latches 3 are loaded by the tensile force of the element 32. Statically, the hanging arrangement of this element 32 with the locking configuration, latch insert 3;4, means no difference to the function of the lock. To increase the utility value, the hanging element 32 is provided with receiving tabs 32 for writing instruments, such as ballpoint pens, pencils, etc.

Fig. 11 shows a similar design of the pocket 24 as a folder 26 to Fig. 10. The flap 28 is designed so that it covers the intermediate layer 6. The latches 3 are designed in the outer extension of the flap 28 so that they can be brought into an operative connection in corresponding slots 4 of the intermediate layer 6. A card 27 can advantageously be placed on the flap 28. The card 27 has four latches 3' that can be brought into engagement in corresponding slots 4 on the flap 28. This ensures that the card 27 can be releasably fixed to the flap 28. Tabs are arranged on both side edges, which are largely due to pragmatic handling when the folder 26 is decorated in color.

Fig. 12 shows a solution similar to the design in Fig. 10a in a separate configuration. This shows a hanging box 32 which is held in slots with its latches. The hanging box 32 can be arranged anywhere. The prerequisite is the presence of slots that correspond to its dimensions. This makes it possible to use the hanging box 32 to accompany freight, to hold accompanying documents and for such pragmatic uses as storing notes, napkins, potholders, etc. Here too, what was said about Fig. 10a with regard to the static suitability of the hanging box applies in principle to this type of use.

List of reference symbols used

1 Folded card 2 Top layer 3;3' bars 4 Insert 5;28 Edge 6 Intermediate layer 7 Floor area 8;9;20;8';9' Folded edges 10 compact disk -CD- 11; 11' slot 12 Groove 13 diskette 14;15;16;17;18;19 Page 21 Crate 22 Handle 23;25;28 flap 24 Bag 26 Folder 27 Map 29 Tabs 30 Reinforcing element 31 loop 32 Hanging element

Claims (1)

tit 1 · ♦ » »·· « · Protection claims 1. Closure for the releasable closure of containers made of foldable material, as well as containers suitable for this purpose with devices for fixing objects accommodated in them, in particular made of cardboard or of material with similar mechanical properties, which are suitable for repeated use, characterized in that the closure has a cover layer (2) and an intermediate layer (6), that the cover layer (2) has bars (3) on its front edge (5) in the area of side edges provided with grooves (12), and that inserts (4) are incorporated into the intermediate layer (6) near the folded edges (8; 20), the distance between which and the size of which allow the bars (3) to be pushed in until the grooves (12) rest on the inserts (4) when the projected length of the edge (5) has its greatest extent and the cover and intermediate layers (2; 6) are in their functional position, the contact points of the grooves (12) in the slots (4) are congruent in their distance from each other with the distance between the inner side edges of the slots (4). 2. Closure according to claim 1, characterized in that the distance between the inserts (4) is smaller than the distance between the contact points of the grooves (12) in the inserted position of the bolts (3), whereby the edge (5) is prestressed and the edge (5) is slightly curved away from the intermediate layer (6). 3. Closure according to claim 2, characterized in that the reduced distance between the inserts is 1 to 3 mm. 4. Container equipped with a closure according to claims 1 to 3 with surfaces of approximately equal size in the unfolded position, characterized in that a base part (7) is arranged between each pair of folded edges (8; 8';9;9'), the folded edge pairs (8; 8';9;9') delimiting the base part (7) from cover and intermediate layers (2; 6) adjoining the folded edge pairs (8; 8';9;9') and that the respective folded edges (8; 8';9; 9 ^f ) have slots (11; 1&Ggr;) between them. 5. Container according to claim 4, characterized in that the slots (11; 11') are arranged centrally at equal distances from the side edges of the folded edges (8; 8';9;9'), beginning and ending. Erich and Nern, Patent Attorneys GBM 154/A - 2 - 6. Container according to claim 4, characterized in that the slots (11; II ¹ ) are arranged at irregular distances from the side edges of the folded edges (8; 8';9;9'), beginning and ending, in the middle on the outside. 7. Container according to claims 1 to 6, characterized in that in the slots (11;1&Ggr;) of the container, which is designed as a folding card (1), rotationally symmetrical flat bodies with a larger diameter than the extension of the base surface (7) between the folded edges (8;9) are arranged. 8. Container according to claims 1 to 6, characterized in that in the slots of the container, which is designed as a folding card (1), polygonal flat bodies with a greater extension between the corners than the dimension of the base area (7) between the folding edges (8; 9) are arranged. 9. Container of cubic shape, using the closures according to claims 1 to 3, characterized in that the closures are arranged on at least one side of the container. 10. Container according to claim 9, characterized in that the closures are arranged on at least three sides of the container, two closures being provided on the opposite sides. 11. Container according to claim 10, characterized in that the closures are arranged on three sides of the container and are accessible independently of one another for opening and closing operations as well as for filling operations of the container. . Container designed as a flat box or as a bag, using the closure according to claims 1 to 3, characterized in that the container (21; 24), designed to be flat, has a rectangular shape with a small height and the inserts (4) are recessed in the surface of the container (21; 24) and their position is adapted to the overlap length of a flap (23), on the edge (5) of which, on their outer extensions, the latches (3) are arranged, which are inserted into the inserts (4), closing the box (21) with the flap (23). Erich and Nern, Patent Attorneys GBM 154/A - 3 - 13. Bag according to claim 12 with a flap folded over the bag body, characterized in that the flap (25; 28) has a reinforcement running over the flap (25; 28) parallel to its edge (5) from the outer edge of the latches (3). 14. Bag according to claim 13, characterized in that the reinforcement consists of a flat, leaf spring-like insert. 15. Clamp card provided with the closures according to claims 1 to 3, characterized in that the card (27) has a pair of latches (3 ¹ ) on each of its lateral extensions, which are brought into operative connection with corresponding inserts (4) by insertion and are arranged on the flap (25; 28) of a pocket (24) and a folder (26). 16. Clamp card according to claim 15, characterized in that loops (31) for writing instruments, such as fountain pens and ballpoint pens, are arranged on the outwardly directed surface of the clamp card (27). 17. Hanging boxes provided with the closures according to claims 1 to 3, characterized in that the box has an upwardly extended rear wall, on the upper edge (5) of which bars (3') are arranged on both sides, which correspond to inserts (4) of a holding position and are brought into an operative connection for fixing the position of the box in such a way that the contact points in the grooves (12) in the edges of the inserts (4) come to rest firmly. 18. Hanging box according to claim 17, characterized in that loops (31) for receiving writing instruments are provided on the rear wall (30).