Abstract:
A method and an apparatus are provided for inserting a fastener ( 3 ) into a flexible plate or strip ( 1 ) which shall act as a packing structure and which has a channel fitted with two lips ( 2   a,    2   b ) partly closing the channel, the fastener ( 3 ) to be inserted between the lips. The method includes slightly bending the plate or strip ( 1 ) transversely to the direction of its channel in a way to spread apart its lips ( 2   a,    2   b ), furthermore to insert the fastener ( 3 ) and to substantially reflatten the plate or strip ( 1 ) in order that the lips ( 2   a,    2   b ) shall resume their initial positions.

Description:
TECHNICAL FIELD 
     The invention relates to a method and to an apparatus for inserting a fastener into a flexible strip or plate that shall constitute a packing structure. 
     BACKGROUND ART 
     It is known, when packing, to gird the said packing structure—for instance a cardboard structure—with a hoop or the like, illustratively a plastic strip, in order to close or rigidify said packing structure. 
     This kind rigidification entails the difficulty that the packing structure must be held in place when being hooped and obviously both the packing structure and its hooping means must be handled simultaneously. 
     SUMMARY OF THE INVENTION 
     Accordingly the inventor conceived of a method and an apparatus for inserting such a fastener into a flexible plate or strip that shall constitute the packing structure and which is fitted with a channel comprising two lips that partly close said channel, said fastener being inserted between these two lips. 
     The method of the invention is characterized in that it slightly bends the plate or strip transversely to the channel direction in a way to move apart its lips, in inserting the fastener and in substantially flattening again said plate or strip in order that these lips resume their initial positions. 
     Moreover, in one embodiment of the present invention, the plate or strip is displaced longitudinally relative to its channel during the transverse bending and flattening operations while illustratively the plate or strip shall be guided before being bent by at least one means inserted into its channel. 
     The fastener also may be advantageously held in position against the bottom of the channel by depressing it during the re-flattening stage. 
     Preferably the channel lips shall be crushed after the plate or strip has been re-flattened. 
     Illustratively the fastener being used in the present invention is in the form of a hoop or the like, even though it also may be in other forms such as cables etc. 
     To carry out such a method, the invention also proposes an apparatus which is characterized in that it comprises a sub-assembly for slightly transversely bending the plate or strip, further an element inserting the fastener and a sub-assembly re-flattening the plate or strip, as well as elements driving the plate or strip in its channel&#39;s longitudinal direction. 
     In one embodiment mode of the invention, the bending sub-assembly consists of two superposed wheels of which the rims resp. are one substantially concave and one substantially convex surface, the plate or strip being made to pass through said wheels and its channel facing the concave-rim wheel. 
     In this embodiment, advantageously the element inserting the fastener consists of a guide ramp feeding said fastener, the end of said ramp extending as far as the vicinity of the bending wheels and between them, said fastener moreover being fitted with a circular rib on the concave wheel in order that the rib may press against the fastener during bending. 
     Preferably the strip re-flattening element comprises straightening fins which pass gradually from an oblique to a substantially plane position, and the apparatus of the invention also comprises a fastener holding-element configured above the straightening fins and optionally in the form of a small bar. 
     The apparatus of the invention also may comprise an initial holding and guiding element for the plate or strip, which is configured upstream of the bending subassembly as seen in the direction of motion of the plate or strip, and which is a cylinder on which moves said plate or strip, further comprising a roller that rests against the bottom of the channel in said plate or strip. Moreover an aligning guide in the form of a small bar may be configured between the initial holding and guiding element on one hand and the bending sub-assembly on the other. 
     Advantageously a sub-assembly crushing the channel lips and in the form of compression drums is configured downstream of the re-flattening element. 
     The elements driving the plate or strip in its longitudinal direction illustratively consist at least in part motors powering at least one of the bending sub-assembly wheels and/or the initial holding and guiding cylinder and/or at least one of the drums crushing the channel lips. 
     As regards a plate or strip which is additionally fitted with a substantially right-angle flange for the purpose of constituting a bracket, the apparatus of the invention also may be characterized in that the cylinder of the initial holding and guiding element and one of drums of the crushing sub-assembly do comprise a peripheral, circular channel to receive the substantially right-angle flange of the plate or strip. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention is elucidated in the description below which relates to the attached drawings: 
     FIG. 1 shows a plate or strip with a hoop inserted into it by the apparatus of the invention, 
     FIG. 2 is a schematic perspective of an apparatus of the invention, 
     FIG. 3 is a longitudinal section of FIG. 2 along the arrow III and also shows the plate or strip to be processed, 
     FIGS. 4-8 are sections resp. along IV—IV, V—V, VI—VI, VII—VII, VIII—VIII of FIG.  3 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a flexible plate or strip  1  fitted with a shaped channel  2  comprising two lips  2   a  and  2   b  which partly close said channel  2 , a hoop  3  or the like being inserted into this channel. The channel  2  runs straight and longitudinally. 
     To insert or crimp such a hoop, the invention therefore proposes bending the plate or strip  1  transversely to the direction of its channel  2 , to insert the hoop  3  and to re-flatten said plate or strip. 
     For that purpose the invention proposes the shown apparatus which is displayed especially clearly in FIGS. 2 and 3 and which continuously inserts said fastener in the above described method and of which other features will be discussed below in the description of this apparatus of the invention. 
     The apparatus of the invention is fitted with an initial holding and guiding sub-assembly comprising a cylinder  4 —in this instance it is motor driven as discussed farther below—and a freely rotating roller  5  which is illustratively stressed by a resilient means  6 . 
     The strip  1  moves between the cylinder  4  and the roller  5  rolling inside the strip channel (FIG.  4 ). 
     For clarity&#39;s sake, the various components of FIGS. 3 through 8 are not shown being in contact with the strip  1 . 
     An alignment guide in the form of a small bar  7  received in the channel  2  (FIG. 5) is configured downstream of the cylinder  4  as seen in relation to the strip&#39;s direction of advance shown by the arrow F (FIG.  3 ). 
     Downstream of the small bar  7 , the apparatus of the invention is fitted with the sub-assembly bending the strip  1 , in this instance in the form of two superposed wheels  8  and  9  between which passes said strip  1 . 
     As shown in FIG. 6, the rims of the wheels  8  and  9  resp. exhibit a concave surface (wheel  8 ) and a substantially convex surface (wheel  9 ), the channel  2  of the strip  1  facing the concave wheel  8  in such a way that the strip  1  shall be slightly transversely bent as shown in this FIG.  6 . 
     The hoop  3  is fed from a storage means, for instance a coil  10  (FIG. 3) along a guidance ramp  11  (FIGS. 2,  3 ) of which the end reaches the vicinity of the wheels  8  and  9 , whereas said concave wheel  8  is fitted with a central and circular rib  12  (FIG. 6) to support the hoop  3  and to keep it in position in the channel  2 . 
     An element re-flattening the strip  1  and in this instance in the form of straightening fins  13  (FIG. 7) is configured in the exit zone of the bending wheels  8  and  9 , said fins progressively passing from an oblique position (relative to the horizontal) to a substantially plane position (FIG.  2 ). 
     An element in the form of a small bar  14  is configured above the straightening fins to keep the hoop  3  in position. 
     When leaving the straightening fins  13 , the strip  1  therefore is flattened again and is made to pass between two compression drums  15 ,  16  (FIGS. 2,  3  and  8 ) to crush the assembly for the purpose of closing again the channel lips  2   a  and  2   b  on the hoop  3 . 
     FIGS. 2 and 3 moreover show that the wheel  8  of the bending sub-assembly and the drum  15  of the crushing elements (such as the above described roller  5 ) are loaded in resilient manner schematically indicated in FIGS. 1 and 2 by. springs  17  and  18  resp. 
     In the embodiment illustrated in FIGS. 4 through 8, the plate or strip  1  is fitted with a substantially right-angle flange  1 ′ in order to constitute a right-angle bracket. 
     In this latter embodiment, the initial guiding cylinder  4  (FIGS. 2 and 4) and the crushing drum  16  (FIGS. 2 and 8) are fitted with peripheral and circular slots  4 ′ and  16 ′ resp. to accommodate the right-angle flange  1 ′ of the plate or strip  1 . 
     Obviously means also are provided to drive the plate or strip  1 , namely in this instance a schematically indicated drive motor  19  (FIG. 2) which drives into rotation the cylinder  4  (the roller  5  being idle) and/or at least one of the wheels  8  and  9  of the bending sub-assembly and/or at least one of the crushing drums  15 ,  16 . 
     In the light of the above described apparatus of the invention, the working of said apparatus and consequently the method of the invention are easily understood. 
     The plate or strip  1  of FIG. 1, which in this instance is also fitted with a substantially right-angle flange  1 ′, is inserted between the cylinder  4  and the roller  5  and then is driven as elucidated above by the motor  19  (FIG. 2) in the direction of the arrow F (FIG.  3 ), the flange  1 ′ being received in the circular slot  4 ′. 
     After being guided by the alignment guide  7 , the plate or strip  1  is slightly bent transversely (FIGS. 2,  3  and  6 ), while the hoop  3  is continuously deposited into the strip&#39;s or plate&#39;s channel  2  by means of the guide ramp  11 . 
     The assembly is then re-flattened by the straightening fins  13  and the small support bar  14  (FIGS. 2,  3  and  7 ) before being made to pass between the crushing drums  15  and  16  of the lips  2   a ,  2   b  of the channel  2  (FIGS. 1,  2 ,  3  and  8 ), the flange  1 ′ being received in the slot  16 ′ of the drum  16 . 
     Once fitted in this manner, the plate or strip  1  may then be used as any kind of packing structure that in this manner comprises an integrated fastener. 
     Using a strip in particular, a protective packing structure in the form of a collar to enclose at least part of a cylindrical object. 
     Illustratively the end of a pipe or tube may be protected by using a strip fitted with a substantially right-angle flange in the manner discussed above.