Patent Publication Number: US-6910598-B2

Title: Container comprising a turn-lock fastener

Description:
FIELD OF THE INVENTION 
   The invention relates to a container for accommodating free-flowing products, in particular in the form of a beverage can which is provided with a predetermined breaking line which, once broken open, produces a drinking or pouring opening. 
   BACKGROUND OF THE INVENTION 
   Beverage cans usually have a horseshoe-shaped predetermined breaking line which bounds a wall region on which a ring-pull tab is fastened. If such a beverage can has been opened by virtue of the tab being actuated, it is no longer possible to close it effectively, which, in the case of carbonated drinks, results in the can contents having to be consumed rapidly or the drink otherwise going flat. 
   In order to eliminate this shortcoming, it is already known (from DE 196 13 256 A1) to provide a lid-like closure element which has engagement elements which interact in the manner of the bayonet closure with mating engagement elements on a cylindrical wall of the can, the so-called core wall, in order thus for a drinking or pouring opening made in the can to be closed in an airtight manner. In order to produce this pouring opening, the closure element has arcuate pressure-exerting elements which engage in a canal of the lid wall of the can and, when the closure element is rotated, slide onto an obliquely upwardly sloping pressure-exerting surface of the canal in order thus to break open the predetermined breaking line which extends around the edge of the lid wall of the can. The disadvantage with this configuration of the beverage can-is the fact that the shape of the outline differs from that of the conventional beverage cans, with the result that it is not possible to stack these beverage cans with conventional beverage cans. During use, moreover, the closure element has to be removed from the beverage can in order to free the pouring opening. 
   A container as known from U.S. Pat. No. 3,726,432 is provided with a flat lid wall having a depression with a sloping surface wherein a tongue extends downwardly from an additional rotary lid closure. The container lid wall comprises a predetermined breaking line which encloses a circular section and a narrow arcuate section, the predetermined breaking line being interrupted in the circular section at a position which is opposite to the narrow arcuate section. When the additional rotary lid having the tongue on it is rotated, the tongue initially enters into the narrow arcuate section and then into the circular section and breaks the breaking line so as to pivote the wall flap so formed into the interior of the container. The wall flap is thereby bent at a position which is arranged between the ends of the predetermined breaking line. There is the danger that the lid wall makes a bulging or swell at this position so that no flat engagement exists with the wall of the rotatable lid and no good sealing can be expected. 
   A tin having a pair-of cap-shaped portions, each of which being surrounded by a predetermined breaking line can be opened with the help of an additional cover to be placed on the tin and having rising edges for opening the cap-shaped portions (see ˜EP-A-0,340,835). The additional cover also comprises a pair of cylindrical parts which may be plugged into the openings of the container lid when the same have been opened by breaking the circular breaking lines in the container lid. It is doubtful whether or not such an opening can be sealingly closed in such a manner. 
   A beverage container is known from U.S. Pat. No. 5,816,427 which has drinking and pouring openings formed by slots parallel to one another, and a rotatable cover for forming the slots into the container lid and for covering same. Sealing of the beverage container which has been opened is not possible by this cover. 
   A further beverage container is known from U.S. Pat. No. 5,692,633 which has a rotary lid closure and a fixed container lid including a circular raised region surrounded by a predetermined breaking line. The rotary lid closure comprises an opening corresponding to the outline of the breaking line and a raised portion or emboss having a sloping surface which narrowly encompasses the raised region of the container lid. When rotating the rotary lid closure, the raised region of the container lid is sheared off along the predetermined breaking line. 
   SUMMARY OF THE INVENTION 
   A object of the present invention is to provide a container with rotary closure which can be configured such that it can be stacked with conventional containers of the same type. 
   A further object of the invention is to provide a container with rotary closure which is also suitable for sealing carbonated beverage. 
   A further object of the invention is to provide a container with rotary closure in the case of which the drinking or pouring opening can be opened and closed simple by virtue of the rotary closure being rotated (without being removed). 
   A further object of the invention is to provide a container with rotary closure in the case of which, on account of its relative size, a single pouring opening is sufficient to serve as a drinking opening. 
   The invention provides a rotary lid closure which is fitted rotatably on the container. The rotary lid closure has a protrusion by means of which a pouring opening in the lid wall of the container can be opened by virtue of the rotary lid closure being rotated. The rotary lid closure also has a cut-out opening which can be made to coincide with the pouring opening in the lid wall of the container in order for contents to be removed from the container. The cut-out opening in the rotary lid closure may also be rotated to a neutral location, whereupon wall parts of the rotary lid closure cover and close the pouring opening in the lid wall. The container and the rotary lid closure are provided with supporting means, with the result that the extent of support of the wall of the rotary lid closure on the edge of the pouring opening in the lid wall is sufficient to seal even carbonated beverage. 
   In detail, the rotary lid closure is positioned on the can as a cap and retained thereon by means of clips which, in the case of commercially available metal cans, engage behind the edge seam. Three clips are sufficient, and these grip firmly, by way of their depressions, on the edge seam and retain the rotary closure without preventing the latter from rotating. The cap form of the rotary closure provides sufficiently large grip surface areas for the hand, with the result that the rotary closure can be conveniently grasped and rotated, a long lever length being formed. In order to open the pouring opening, i.e. that region of the lid wall which is bounded by notched weakening lines, a protrusion is provided on the rotary closure, and this protrusion can be pressed into the bounded region by virtue of the rotary closure being actuated, with the result that the lid breaks along a short section of the weakening lines. Further rotation of the rotary closure allows the protrusion to be displaced over the surface of the bounded region, with the result that the lid wall is increasingly bent downward in this bounded region and the crack propagates along the notched weakening lines until the pouring opening has been completed. In the preferred embodiment of the invention, the cut-out opening in the rotary lid closure here overlaps with the pouring opening in the lid wall of the container. The container is closed by virtue of the rotary lid closure being rotated back. 
   It is particularly advantageous that it is possible to use commercially available cans, the only difference being that, instead of fitting the ring pull tab, the latter is replaced by the rotary closure. It is further advantageous that the rotary closure seals well in its closed position, with the result that it is even possible for carbonated beverage to be kept under a certain pressure in the can. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
     The invention will be described with reference to the drawing, in which: 
       FIG. 1  shows, in an exploded view, a section through the top part of a can with rotary closure, 
       FIG. 2  shows the view of the lid wall of the can, on a larger scale than  FIG. 1 , 
       FIG. 3  shows a section along line III—III from  FIG. 2 , 
       FIG. 4  shows the view of a rotary closure, 
       FIG. 5  shows schematic illustrations of the operation of opening the can, 
       FIG. 6  shows a clip formation, 
       FIG. 7  shows an enlarged detail, in section, 
       FIG. 8  shows a section through the top part of a second embodiment of the can with rotary closure, 
       FIG. 9  shows a plan view of the can according to  FIG. 8 , 
       FIG. 10  shows an enlarged detail from  FIG. 8 , 
       FIGS. 11  to  13  show the operations of opening and closing the can, and 
       FIGS. 14  to  16  show the operations of opening and closing a variant of the can. 
   

   DESCRIPTION OF THE EMBODIMENTS 
     FIG. 1  shows the top end of a can, i.e. a rotationally symmetrical wall region  1 , e.g. made of tin plate, which is closed by a lid wall  2 , e.g. made of aluminum, an edge seam  3  being formed. The lid wall  2  has an encircling groove  8  and a bounded region  5 , which is sunken to some extent in relation to the plane of the lid wall  2  and has been prepared via notched weakening lines  6 , as predetermined breaking lines (FIG.  2 ), for a partial breaking-open action. Two latching locations in the form of indents  7   a ,  7   b  are also provided on the lid wall  2 . 
   As can be seen from  FIG. 2 , the weakening grooves  6  have arcuate sections  6   a ,  6   b ,  6   c  and  6   d . The arcuate sections  6   a  and  6   b  run more or less along radial lines, which are angled at just below 90° in relation to one another. The section  6   b  is somewhat longer than the section  6   a . The sections  6   c  and  6   d  run approximately concentrically with the center axis  4 , the concentricity not quite being achieved on account of running toward the longer section  6   b.    
     FIG. 1  also illustrates a rotary lid closure  10 , as a section I—I from  FIG. 4 , which consists of metal or plastic and has an encircling annular wall  11  with funnel-shaped widening  12  and a rotary sliding wall  13 . The rotary sliding wall  13  has a cut-out opening  15  which is of more or less the same shape as the bounded region  5  of the lid wall  2 . Parts of the wall  13  in the region of the opening  15  are bent over in a loop-like manner in order to form a bead-like protrusion  16 , as can best be seen from  FIG. 5. A  bead  17  is also provided, as a protrusion, in the wall  13  and engages in one indent  7   a ,  7   b  or the other in order to determine a defined open position and closed position for the can as a whole. 
   The rotary closure  10  is fitted onto the can  1  in the manner of a lid, and it engages behind the edge seam  3  by way of a number of clips  20 , e.g. three resilient depressions (FIG.  6 ). In addition, a protruding annular corrugation  21  engages in the groove  8  in order for the rotary sliding wall  13  to be guided resiliently, and thus in a close-fitting manner, on the side wall  2  when the rotary closure is rotated. The rotary closure  10 , in addition, is made particularly easy to grip by the annular wall  11  being designed with corrugation or knurling. 
   In order to achieve a pressure-tight closure, it is expedient to rubber-coat the front side  16   a  of the bead-like protrusion  16  and the underside of the wall  13 , at  13   a , or to provide the same with some other sealing coating. 
   It is further expedient to provide a bead-like sealing application around the bounded region  5 , outside the predetermined breaking line  6 , with the result that the contact pressure of the rotary closure  10  is greatest around the bounded region  5 . 
   In the starting position of the can, or in the position in which the latter is supplied, the bead-like protrusion  16  is located within the bounded region  5 , overlapping the edge region  6   a . In this starting position, the protrusion  17  latches into the indent  7   a  and thus fixes this starting position. By using one&#39;s thumb to press on the bead-like protrusion  16 , the notched weakening lines  6  can be made to break in the region  6   a , as is illustrated at the top left of FIG.  5 . The edge  11 ,  12  of the rotary closure  10  is then grasped and rotated in the counterclockwise direction, as seen in FIG.  4 . The bead  16  then bends the bounded region  5  increasingly downward in the form of a lug  5   a , as is outlined at the top right and bottom left of the illustration of FIG.  5 . This forms the drinking or pouring opening  9 , which takes up approximately the bounded region  5 . This opening  9  can be freed by virtue of the rotary closure  10  being rotated back, as is illustrated at the bottom right of FIG.  5 . In this position, the opening  9  and the cut-out opening  15  of the rotary closure  10  overlap, which allows maximum removal of the contents of the containers. Counterclockwise rotation can partially or wholly eliminate the overlapping position formed, with the result that the effective outlet opening is more or less pronounced or closed, the latter being the case when the bead  17  engages in the indent  7   b.    
   In this closed position, the sealing coating  16   a  of the bead  16  comes into contact with the edge  2   a  of the opening  9 , as is illustrated at the bottom left of  FIG. 5 , and the coating  13   a  seals against the wall  2 . 
     FIG. 7  shows the interaction of the bead  16  with the bounded region  5  without the aid of the thumb. The bounded region has three zones  5   a ,  5   c  and  5   d  with sloping surfaces as well as plateau zone  5   b . If the rotary closure lid is rotated out of the starting position, the bead  16  slides along the sloping surface  5   a  in the direction of the plateau surface  5   b  as a result of which the pressure on the lid  2  increases and the weakening line breaks in the boundary region between  6   c  and  6   a . This tear propagates via the region  6   a  into the region  6   d  and passes, via the region  6   b , into the region  6   c , in which the weakening line is interrupted in order that the separated-off part  5  remains attached to the lid  2  and does not fall into the interior of the container. The steeper the sloping surface of the zone  5   a , the greater is the initial force which needs to be applied in order to cause the weakening line to break. The angle of the sloping surface is between 20 and 40°. 
   The rotary closure lid  10  is preferably dimensioned such that the base of an adjacent can fits into the top edge opening of the lid  10 , with the result that it is possible for a number of cans to be stacked one above the other with mutual engagement. 
     FIGS. 8  to  13  show a second embodiment of the can with rotary closure. Parts which correspond to those of the first embodiment are provided with the same designations, and reference is made to the appropriate description of the first embodiment. 
   The notched weakening line  6  has a kidney-shaped outline with a convexity  6   e , at which location the notched weakening line is interrupted. The bounded region  5  of the lid wall  2  is broken away in order to form the drinking opening  9 , but, in order to be captive, remains attached to the lid wall in the region  5   e . The bounded region  5  is broken out in a similar manner to the first embodiment, although the sloping surface  5   a  is somewhat narrower and longer than the sloping surface of the first embodiment. Accordingly, the protrusion  16  of the rotary lid closure  10  is shorter in the radial direction and only extends downward from the rotary sliding wall  13 , i.e. it is designed as an indent or bead which assumes a certain spacing S 1  ( FIG. 13 ) from the cut-out opening  15 , which is provided in the rotary sliding wall  13  and has a kidney-shaped or bean-shaped outline. The spacing between the indent or bead  16  and the axis of rotation  4  is designated S 2 . The depression of the kidney shape is at a certain spacing S 4  from the axis of rotation  4  of the rotary lid closure  10  and at a spacing S 3  from the edge of the lid wall  2 . A sealing layer or a sealing bead is applied up to this spacing strip around the zone  5 , which will be discussed in more detail in conjunction with  FIGS. 14  to  16 . 
   With the system of the invention, the closed half of the rotary sliding wall  13  overlaps the opening or the region  5 , which could thus take up up to half of the surface area of the rotary sliding wall  13 . Since it is desirable for the drinking opening  9  to have rounded edges, and since the broken-out section of the wall is to remain attached at the web  5   e , the maximum size of the drinking opening  9  is correspondingly smaller. Since the drinking opening  9  is to be sealed, there is a need for a sealing surface around the opening. The spacings S 1 , S 3  and S 4  are thus required. In the embodiment described, the openings  9  and  15  have virtually achieved their maximum size for practical purposes. It would only still be possible to increase the size of the openings  9  and  15  to some extent by increasing the spacing S 2  between the protrusion  16  and the axis of rotation  4 , as a result of which the outlines of the openings  9  and  15  may be of somewhat more slot-like configuration. The radial extent of the opening  9  or  15  is r− (S 3 +S 4 ), where r is the radius of the rotary sliding wall. This radial extent should be at least r/2, in order to achieve a sufficiently large drinking opening in the case of commercially available beverage cans of 65 mm in diameter. The protrusion  16  should extend approximately tangentially to the predetermined breaking line  6  and should pass over the region  5  approximately in its center. This means that the direction in which the protrusion  16  extends is at an angle of from approximately 30° to 60° to the radial line, in respect of the conditions from  FIGS. 8  to  13 . For the spacing S 2 , a range of from 0.3 to 0.6 r is preferred. 
   The rotary lid closure  10  is clipped onto the top end of the can in the same way as in the case of the first embodiment. However, the encircling annular wall  11  terminates with a flanged border  11   a , as is illustrated in FIG.  10 . As can be seen from  FIG. 9 , the annular wall  11  may be of corrugated form, in order for it to be possible for the rotary lid closure  10  to be rotated with greater force. 
   The handling of the rotary lid closure is outlined in  FIGS. 11  to  13 .  FIG. 11  shows the position of the rotary lid closure  10  once it has been fitted in the position in which it is sold. If the customer wishes to open the can, he/she rotates the rotary lid closure  10  to the left, as is indicated by the arrow PI. The protrusion  16  moves over the sloping zone  5   a , the increasing pressure ensuring that the notched line  6  breaks. During this rotation P 1 , the opening  15  passes into the bounded region  5  and, finally, overlaps the latter to the full extent, as is illustrated in FIG.  12 . During this rotation in accordance with the arrow P 1 , the wall region  5  pivots into the interior of the can  1 , but remains attached to the lid wall  2 , as is illustrated at  5   e . The drinking opening  9  is open to the maximum extent in the position of FIG.  12 . 
   The rotary closure can be closed again by virtue of the part  10  being rotated to the right in accordance with the arrow P 2 . The position of the rotary lid closure according to  FIG. 13  is then reached. In this case, the protrusion  16  comes into abutment against the edge of the open region  5 . The angle position of the rotary closure  10  is thus somewhat different from the angle position in the starting position of FIG.  11 . This means that a sickle-shaped region  2   b  is visible from the lid wall  2 , which region was still concealed in the position of FIG.  11 . This sickle-shaped region  2   b  may be marked in order to indicate to the expert that the can has been opened or that an attempt has been made to open it. 
   The tamper indicating feature) may also be realized in some other manner, for example by means of a seal which is adhesively bonded to the lid wall  2  and the rotary sliding wall  13  in the region of the opening  15 . When the rotary lid closure  10  is rotated, this seal has to be destroyed, which indicates the unauthorized usage of the can. 
   The safety feature may also be provided in the region of the edge  11   a  of the annular wall  11 , since it is also the case there that rotation of the closure  10  involves displacement relative to the can  1 . 
   It may be expedient for containers to have a pouring opening with a round cross section, for example because it is desired to fit in a pouring tap or the like there. The variant according to  FIGS. 14  to  16  shows such a circular access opening  15 . The predetermined breaking lines  6  are approximately horseshoe-shaped and enclose a correspondingly configured region  5 , around which a bead-like sealing region  5   f  extends. If the closure  10  is rotated to the left in accordance with arrow P 1 , the protrusion  16  moves over the sloping surface  5   a  and presses the wall region  5  downward, with the result that the predetermined breaking line  6  tears, with the exception of the region  5   e , which remains attached. The part  10  contains a protrusion  17  which latches into a corresponding indent of the lid wall  2 , as is similarly illustrated at  7   a  in FIG.  2 . In this angle position of the rotary lid closure  10 , the opening  15  overlaps the now open region  5  to the maximum extent, as is illustrated in FIG.  15 . The rotary sliding wall  13  butts with pressing action against the sealing region  5   f . It should be pointed out that the rotary sliding wall  13  is provided with resilient compliance, in particular in the region of the annular groove  21 , so that the sealing abutment of the rotary sliding wall  13  against the sealing region  5   f  still functions even when the lid wall  2 , as a result of the internal pressure loss when the can is opened, yields back to some extent, i.e. loses its original relatively large degree of curvature. 
     FIG. 15  shows the open position of the container, which can be transferred into the closed position of  FIG. 16  by virtue of rotation to the right in accordance with arrow P 2 . From this position, the container can be opened repeatedly by virtue of the rotary lid closure  10  being rotated to the left in accordance with arrow P 3 . 
   The can  1  may be further developed as a music box, in which a microchip with micro power source and micro-loudspeaker is fitted on the lid or lid roof closure, the microchip taking effect when the can is opened, or when the rotary lid closure is rotated, and playing a melody, an advertisement or the like. 
   The novel rotary closure can be used not just for cans but also for other forms of containers or vessels which have a rotationally symmetrical wall with a lid wall which has to be torn open in order to form a pouring opening. 
   The novel rotary closure is very user-friendly. The cap-like design of the rotary closure allows convenient grasping without any risk of injury (i.e. without fingernails being broken or cuts being sustained on the ring pull, as in the case of prior-art containers). Moreover, the rotary closure provides a favorable lever action since the grip location  11  is located further outward relative to the actuating location  6 / 16 . On account of the straightforward design, the additional costs of the rotary lid closure are only slightly higher than the hitherto conventional containers with ring pull tab, and these additional costs are offset by the advantages which can be achieved. The can can be opened and closed repeatedly and is leakproof and seals against the loss of carbonated beverage. With the can closed, there is no risk of insects, which could have fallen into the open containers, being swallowed (exclusion of warranty claims).