Patent Publication Number: US-2021188496-A1

Title: Closing ring closure device

Description:
The present invention relates to a closing ring closure device for a closing ring with a closing lever and a one- or two-piece traction bracket, each of which are mounted pivotably via a pivot bearing on a pivot bearing base on the closing ring, wherein the traction bracket and the closing lever are pivotably connected via another common pivot bearing. The present invention further relates to a closing ring with said closing ring closure device. 
     Closing rings usually have a U-shaped or trapezium-shaped profile, in which a flat or rounded center piece connects an upper and a lower closing ring arm. At least one of the two closing ring arms is designed to run at an angle, and often both closing ring arms are designed to run at an angle, with the distance between the two closing ring arms increasing inwards towards the center of the closing ring. In special embodiments of closing rings, an upwardly or/and downwardly angled collar-shaped flange edge may adjoin the upper or/and lower closing ring arm. 
     The closing ring closure device bridges the two ends of the closing ring with the closing ring-side pivot bearing base of the closing lever being permanently welded onto one end of the closing ring and the closing ring-side pivot bearing base of the traction bracket being permanently welded onto the other end of the closing ring. When the closing lever is closed, the closed closing ring has its smallest diameter, and when the closing lever is opened, the open closing ring has its largest diameter. The largest diameter of the opened closing ring is required when putting on or taking off the closing ring from the cover flange rim and drum body flange rim, for this purpose the closing lever must be held by hand in fully opened position. The smallest diameter of the closed closing ring with the closing lever folded in is required for axial clamping and pressing together of the fitted drum lid with the drum lid seal onto the drum body opening or the drum body rim. 
     Closing rings with a closing ring closure device for the detachable fastening of a drum lid to a lidded drum are known in a wide variety of embodiments, for example from DE 20 2013 000 452 U1 (Berger). In the closing ring described therein, the closing lever is fixed in the closed position by constructive means in order to prevent the closing lever or the closing ring closure from opening accidentally or unintentionally. In the known state of the art, there are many other proposed solutions for securing or fixing the closed closing lever in the closed position. 
     Problem 
     However, the present invention is directed at a different problem. In the manufacture of closing rings, on the one hand the closing ring closure device with its two pivot bearing bases must be welded onto the two ends of the closing ring. Since the closing lever is connected to the traction bracket only by means of a pivot pin, and the closing lever and traction bracket are also pivotably mounted on the outside by means of pivot bearings on the two pivot bearing bases, this prefabricated component unit is a comparatively unstable system which is difficult to handle. 
     On the other hand, when opening a lidded drum, the closing lever of the closing ring must be brought into a wide open position and held manually in order to be able to lift the opened closing ring off the drum lid or lidded drum. When closing the lidded drum, the closing lever of the closing ring must again be held in a wide open position with the largest diameter and only then the opened closing ring can be placed over the edge of the fitted drum lid and the edge of the lidded drum and can be firmly closed. 
     It is the object of the present invention to simplify the handling of a closing ring closure device as a prefabricated component unit during further processing as well as to simplify the handling of a closing ring with welded-on closing ring closure device during the closing and opening of a lidded drum with drum lid and to enable further automation in closing ring production as well as in lidded drum closing machines. 
     This object is solved according to the invention in that the two components closing lever and traction bracket are provided with constructive means which are designed in a mutually coordinated functional mode between the two components as a snap-fit device for fixing the closing ring closure device in a wide open closing lever position. 
     As a constructive means, the closing lever or/and the traction bracket are provided with a special locking device which fixes the closing lever in a wide-open position at an opening angle of greater than 90°. 
     By fixing the closing ring closure device in a wide-open closing lever position by means of the locking device designed as a snap-fit device, the closing ring closure device can be handled much easier during further processing. As a prefabricated component unit, the closing ring closure device, which consists of four individual components each pivotably connected via pivot bearings, is now no longer an unstable chain of components, but with a defined rigid position it can be inserted into a supply magazine and then fed, for example, to an automatic welding machine for welding the pivot bearing bases to the closing ring blank. After completion of the welding process, the finished welded closing ring with locked closing ring closure device can be transported in wide-open closing lever position by an automatic gripping and conveying device to a lidded drum closing machine, where the wide-open closing ring is automatically placed on a lidded drum with drum lid and closed. 
     In a constructive embodiment of the invention, it is provided that the locking device is designed as a snap-fit device with a snap element and a latching element, wherein the snap element is arranged either on the traction bracket or on the closing lever and the latching element is arranged correspondingly opposite on the closing lever or on the traction bracket. 
     The mutual locking of the closing lever and the traction bracket results in a wide spread or wide opening of the closing ring closure device and thus makes it possible to store and transport this component group in a defined stable arrangement and to generally simplify and facilitate the handling of a closing ring provided with the closing ring closure device according to the invention. 
     In a specific embodiment of the invention, it is provided that the traction bracket or brackets have two parallel outer flanks facing each other, each of which is provided on its inner side with at least one protrusion directed towards the opposite outer flank and latching into a corresponding notch or recess in any of the outer sides of the side walls when the closing lever is in wide open position. 
     Particularly in the case of closing rings with a larger diameter, e.g. for 220 l lidded drums, the two parallel, opposing outer flanks of the traction brackets are interconnected via a common center piece and are formed as a one-piece component. This results in greater stability of the entire closing ring closure device. 
     In a further embodiment of the closing ring closure device, the snap-fit device arranged between the traction bracket and the closing lever is designed in such a way that, when the closing lever is in the wide open position, the snap element engages with the latching element, with the closing lever being fixed against the traction bracket at an opening angle of greater than 160°. 
     In the preferred embodiment of the closing ring closure device according to the invention, the traction bracket has short extensions on both sides beyond the pivot bearing C common to the closing lever, and said extensions each have indentations on the outside and, respectively, protrusions (latching cams) on the inside pointing inwards, wherein in the side walls of the closing lever corresponding recesses are provided on both sides, into which the protrusions can be snapped and latched opposingly (vis a vis) in a locking manner, when the closing lever is in wide open position. 
     When looking at a closing ring with closed closing ring closure, the closing lever rests on the closing ring and the opening angle is zero. When the closing ring closure is open, the closing lever is usually at right angles to the closing ring, i.e. the opening angle is about 90 degrees. The closing ring is now no longer under tension stress, but must still be opened further and held by hand to be placed on the drum lid or to be removed from the lid rim. Whereas, by locking the closing ring closure device in a wide-open position at an opening angle of the closing lever of greater than 160°, the closing ring can be easily removed from the edge of the drum or lid without the closing lever having to be held by hand all the time. At the same time, it is now possible to fully automatically place and close closing rings with a locked closing ring closure device in fully open position and with the largest possible diameter on drum lids of lidded drums in automated lidded drum closing systems. 
     In another preferred embodiment of the invention, the closing lever is equipped on its side opposite the pivot bearing C—at the same distance from pivot bearing C as the inwardly pointing protrusions (latching cams) on the extension of the traction bracket—on both sides with corresponding recesses in its side walls such that the protrusions on the extension of the traction bracket can be snapped and latched into the corresponding recesses in the side walls of the closing lever in a locking manner as a closure device for the closing lever, when the closing lever is in the completely closed position. 
     The recesses can also be designed as slotted holes, like the slotted holes already present in the closing lever for the known type of closure by help of a sealing eyelet on the closing ring. 
    
    
     
       The invention is explained and described in more detail below with reference to examples of embodiments shown schematically in the drawings, wherein 
         FIG. 1  shows a closing ring with a closing ring closure according to the invention in side view, 
         FIG. 2  shows an opened closing ring closure in side view, 
         FIG. 3  shows a closing ring closure according to  FIG. 2  in fully open position in side view, 
         FIG. 4  shows a one-piece traction bracket of a closing ring closure, 
         FIG. 5  shows a closing lever in side view, 
         FIG. 6  shows another one-piece traction bracket of a closing ring closure, 
         FIG. 7  shows another closing ring closure in fully open position in side view, 
         FIG. 8  shows a further closing ring closure according to the invention with closed closing lever in side view, 
         FIG. 9  shows a top view of the closing ring closure according to  FIG. 8 , 
         FIG. 10  shows the closing ring closure according to  FIG. 8  with half opened closing lever in side view and 
         FIG. 11  shows the closing ring closure according to  FIG. 8  with almost fully opened closing lever in side view. 
     
    
    
     In  FIG. 1 , reference number  10  indicates a closing ring closure device for a closing ring  12  according to the invention. The main elements of the closing ring closure device  10  are a closing lever  14  and a traction bracket  16 . 
     Such closing rings are used, for example, to seal lidded drums. The drum lids are usually made of plastic or metal, while the drum bodies can also be made of plastic, metal or wound kraft paper (fiber drums, cardboard drums). The closing rings are made of galvanized steel sheet profile and can have diameter sizes from 80 mm to 2000 mm with material thicknesses between 0.5 mm to 2.5 mm. Standard diameters range from 100 mm to 800 mm. In cross-sectional view, the closing rings have a flared U-shaped or trapezoid-shaped profile with or without a collar-shaped flange edge. The closing rings can be formed with a short overlap, long overlap or without overlap below the closing ring closure device. 
     As can be seen in  FIG. 2 , the main elements closing lever  14  and traction bracket  16  are both pivotably mounted on a respective closing ring-side pivot bearing base  22 ,  24  by means of pivot bearings  18  (B),  20  (A), with the traction bracket  16  and the closing lever  14  being pivotably connected to one another by means of a further common pivot bearing  26  (C). Thus, as a prefabricated component unit, the closing ring closure device  10  consists of four individual components  14 ,  16 ,  22 ,  24 , which are pivotably connected to each other by means of three pivot bearings  18  (B),  20  (A),  26  (C). The closing ring closure device  10  bridges the two ends of the closing ring  12 , with the closing ring-side pivot bearing base  22  of the closing lever  14  being firmly welded onto one end of the closing ring  12  and the closing ring-side pivot bearing base  24  of the traction bracket  16  being firmly welded onto the other end of the closing ring  12 . When the closing ring closure device  10  is in closed position, the closing lever  14  rests flat on the closing ring  12 . In this case, a sealing eyelet  46  arranged on the closing ring  12  is covered by a slotted hole  44  arranged in the side walls  38  of the closing lever. To ensure tamper-evidence, a sealing tongue or wire can be passed through the slotted holes  44  on both sides and the sealing eyelet  46 , the integrity of said sealing tongue indicating an originally sealed lid. 
     The shown closing ring closure  10  is in the normally open position, in which the closing lever  14  usually remains in a tension-free position at 90°, projecting approximately at right angles from the closing ring  12 . 
     According to the present invention, the closing ring closure  10  is provided with a locking device  28  in the vicinity of the common pivot bearing  26  of the closing lever  14  and the traction bracket  16 , said locking device  28  in the present embodiment being formed as a snap-fit device with a latching element  42  and a snap element  44  between the traction bracket  16  and the closing lever  14 . The latching element  42  can be arranged either on the traction bracket  16  or on the closing lever  14 , and the snap element  44  can be arranged correspondingly opposite on the closing lever  14  or on the traction bracket  16 . In the present case, the aforementioned slotted hole  44  also serves as a snap element when the closing lever  14  is in the open position. A latching-element  42  is formed by two round indentations arranged side by side which are pressed into the outer flanks of the traction bracket  16  from the outside, said indentations forming on the inside protruding latching cams on the traction bracket flanks. 
     Accordingly, the special design feature of this closing ring closure  10  is that the snap-fit device snaps into a wide-open position of the closing lever  14  in a coordinated functional mode between the closing lever  14  and the traction bracket  16  and fixes the closing lever  14 —with respect to the pivot bearing base  22  on the closing lever side—in a wide-open position at an opening angle of greater than 90°. In the process, the latching cam latching elements  42  snap into the slotted hole snap elements  44   
     This wide-open position of the closing ring closure  10  with the latching cam latching elements  42  latched into the (not visible) slotted hole snap elements  44  is shown in  FIG. 3 . Another slotted hole  48  is provided in the closing lever  14  between the common pivot bearing  26  and the closing ring-side pivot bearing  20 . This slotted hole  48  is of importance only when the closing lever  14  is closed. When the closing lever  14  is closed, the latching cam latching elements  42  snap into this slotted hole  48  respectively snap element and, as an advantageous effect, provide an additional fixation for the closing lever  14  in the closed state. Basically, the latching elements  42  have the same distance from the pivot bearing  26  as the snap elements  44 . 
     Fixing the closing lever  14  in a wide-open position relative to the traction bracket  16  makes the closure device  10  a stable component unit which is much easier to handle during closing ring production. For mass production in series, the prefabricated closure device is now inserted as a stable component unit in a defined spread-out form into a corresponding grid-like holding frame for storage and transport in large quantities. These holding frames are then transported to an automatic welding machine, where they are fed to a supply magazine so that a spread-out or wide-open closure device, which is taken individually therefrom by a gripper of the automatic welding machine, is automatically placed on a closing ring closure device blank, that is fed from another side, and automatically welded onto it. The finished closing rings with welded-on closure device are then stored in the wide-open state in another frame and transported to an intended position at an automatic lidded drum closing machine. There, a drum lid is placed on each lidded drum body by machine and a finished wide-open closing ring is placed over the edge of the drum lid and clamped shut, thus automatically closing the lidded drum. 
       FIG. 4  shows an enlarged view of another traction bracket  16  of a closing ring closure device  10  according to the invention, in which the outer flanks  30 ,  32  are connected by a center piece  40 . In the outer flanks  30 ,  32  of the one-piece traction bracket  16 , two elongated recesses  36  are formed on the outside, which produce protruding rib-like latching cams  34  on the inside of the traction bracket flanks  30 ,  32 . These rib-like latching cams  34  represent the latching elements of the snap-fit device for the closing ring closure device  10 . When the closing lever  14  is in wide open position, the rib-like latching cams  34  snap into the corresponding slotted holes  44  or snap elements in the side walls  38  of the closing lever  14  and fix the two components against each other. 
       FIG. 5  shows another enlarged side view of the closing lever  14  with the two slotted holes  44 ,  48  and the two pivot bearings  18  and  26 . As mentioned, when the closing lever  14  is fully open, the latching elements or latching cams  34  snap into the snap elements or slotted holes  44  and, when the closing lever  14  is fully closed, said latching elements or latching cams  34  snap into the snap elements or slotted holes  48 . 
     In the case of heavier closing rings  12  for larger lidded drums, the closing ring closure devices  10  are no longer provided with two separate sheet-metal strip-like traction brackets, but are equipped with a one-piece traction bracket  16  in which the two parallel, opposing sheet-metal strip-like outer flanks  30 ,  32  are interconnected via the common center piece  40 . The following detailed descriptions of the constructional design of a one-piece traction bracket  16  should of course also apply to two-piece traction brackets. 
     In the preferred embodiment of the invention, the traction bracket  16  is extended by a short piece behind the pivot bearing  26  on the closing ring side (=pivot bearing C). This short part of an extension  54  is approximately as long as the height of the outer flanks  30 ,  32  of the traction bracket  16 , i.e. in the specific case the extension  54  has a length of between 8 mm and 36 mm, preferably 12 mm. The length of the extension should be designed just long enough to ensure elastic behavior of the snap-fit device and to exclude plastic bending of the extension. 
       FIG. 6  shows an example of such a traction bracket  16 , in which the outer flanks  30 ,  32  behind the pivot bearing  26  are each provided with the extension  54 . An indentation  50  is stamped onto each outer side of the extension  54 , which forms an inwardly directed protrusion  52  on the inner side of the extension  54 . In the present case, this inwardly directed protrusion  52  is formed as a round latching cam and represents the latching element corresponding to a snap element (round hole, slotted hole) formed on the outside of the closing lever  14 . 
     Basically, a protrusion ( 34 ,  52 ) or a latching cam or lobe projecting by about 0.5 mm to 1.5 mm is regarded as the latching element and a corresponding recess ( 44 ,  48 ,  56 ) such as a slotted hole, round hole, groove, slot, elongated depression or indentation is regarded as the snap element, which, in interacting, result in a snap-fit device. 
       FIG. 7  shows another closing ring closure  10  in fully open position. Here, the required locking device  28  is formed as a snap-fit device between the extension  54  of the traction bracket  16  and the closing lever  14 , with the latching element being formed as a rib-like protrusion on the extension  54  and snapping into the slotted hole  44  provided on the outside of the closing lever  14  as a snap element. The rib-like protrusion (not visible here) is formed by the likewise rib-like indentation  50 . In this arrested fully open position, the closing lever  14  has an opening angle towards the closing lever-side closing ring end of between 90° and 180°, preferably about 160°. 
     When the closing ring closure device is closed, respectively when the closing ring is closed, the closing lever rests on the closing ring and the three pivot bearings lie almost in an arc line running along the circumference of the closing ring, with the pivot bearing positioned on the pivot bearing base of the closing lever between the other two pivot bearings (A-B-C). When the closing ring closure device is fully open, respectively when the closing ring is open, the back of the closing lever rests almost on the center piece of the traction bracket and the three pivot bearings again lie almost in an arc line, with the common pivot bearing of closing lever and traction bracket now being positioned between the pivot bearing on the pivot bearing base of the closing lever and the pivot bearing on the pivot bearing base of the traction bracket (A-C-B). 
       FIG. 8  shows a side view of a preferred embodiment of the present invention, a closing ring closure  10  according to the invention provided for series production with a closed closing lever  14 . The articulated connection between closing lever  14  and traction bracket  16  is provided by the common pivot bearing  26 . On the side of the traction bracket  16  facing away from the closing lever  14 , the pivot bearing  20  on the closing ring side is arranged with the associated pivot bearing base  24  of the traction bracket  16 . The pivot bearing on the closing ring side and the associated pivot bearing base of the closing lever  14  are arranged below the traction bracket  16  and are not visible here. On the side of the traction bracket  16  facing the closing lever  14 , the extension  54  is formed in the vicinity of the pivot bearing  26 , in which the round indentation  50  with protrusion  52  on the inside (not visible here) is stamped or embossed. In the side wall of the closing lever  14 , the slotted hole  48  for inserting a seal for the closing ring closure in the closed position is visible. Below the slotted hole  48 , a tapering  58  of the closing ring  14  extending to the pivot bearing  18  on the closing ring side can be seen. 
       FIG. 9  shows a top view of the closing ring closure  10 . Here, the extension  54  of the traction bracket  16  beyond the pivot bearing  26  in the direction of the closing lever  14  is visible. At each end of the extension  54 , the indentations  50  are embossed, which snap with their inner protrusions  52  into the corresponding snap elements or round holes  56 . It is convenient to integrate a total of four such round holes  56  in the side walls of the closing lever  14  on both sides of the pivot bearing  26 , as can be seen in  FIG. 10 , which shows the closing ring closure with the closing lever  14  half open. The round holes  56  in the closing lever  14  are arranged at the same distance from the pivot bearing  26  as the distance of the indentations  50  respectively protrusions  52  on the inside of the extension  54  of the traction bracket  16 . 
     When the closing lever  14  is closed (cf.  FIG. 8 ), the inside protrusions  52  of the extension  54  of the traction bracket  16  are seated in the round holes  56  next to the slotted hole  48 , and when the closing lever  14  is fully open, the inside protrusions  52  (latching cams) are seated in the round holes  56  between the pivot bearing  26  and the pivot bearing  18  of the closing lever  14 . As an additional advantage, this ensures a snap-fit arrangement for both end positions of the closing lever  14 , namely locking respectively fixing the closing lever  14  in the open or in the closed position. 
     In  FIG. 11 , the open position of this closing ring closure  10  is shown once again in side view. Here, the protrusion  52  on the inside of the extension  54  is snapped into the round hole  56 , which is arranged between the two pivot bearings  26 ,  18  of the closing lever  14 . As a constructive novelty, this closing ring  12  with closing ring closure device  10  according to the invention is characterized by the fact that, when the closing ring closure device  10  is fully opened and fixed in position, the closing ring  12  has—compared to the closed position—an at least 5% enlarged, rigidly persisting diameter without manual holding of the closing lever  14 . Fully opened closing rings have, e.g. for a 220 l lidded drum, a closing ring diameter of up to 635 mm and can be stored and transported in the open state in a magazine, e.g. to an automatic filling system for lidded drums with subsequent lidded drum closing system for automatically placing and closing the closing rings on the drum lids and lidded drums. 
     REFERENCE NUMBERS 
     
         
           10  closing ring closure device ( 12 ) 
           12  closing ring 
           14  closing lever ( 10 ) 
           16  traction bracket ( 10 ) 
           18  pivot bearing B ( 14 ) 
           20  pivot bearing A ( 16 ) 
           22  pivot bearing base ( 14 ) 
           24  pivot bearing base ( 16 ) 
           26  pivot bearing C ( 14 ,  16 ) 
           28  locking device  28  ( 14 ,  16 ) 
           30  outer flank ( 16 ) 
           32  outer flank ( 16 ) 
           34  latching cams ( 30 , 32 ) 
           36  recess ( 38 ) 
           38  side wall ( 14 ) 
           40  center piece ( 16 ) 
           42  latching element ( 16 ) 
           44  snap element ( 38 ,  14 ) 
           46  sealing eyelet ( 12 ,  22 ) 
           48  slotted hole ( 38 ,  14 ) 
           50  indentation ( 16 ) 
           52  protrusion ( 16 ,  30 ,  32 ) 
           54  extension ( 16 ,  30 ,  32 ) 
           56  round hole resp. bore ( 14 ) 
           58  tapering ( 14 )