Abstract:
A contour roll former capable of operating with different sets of pairs of roll forming heads depending on the type of extruded profile to be produced. The contour roll former includes pairs of heads mounted on carriages capable of sliding horizontally back and forth along a direction transverse to the forming line, so that it is possible to replace one set with another with minimum handling, requiring only horizontal movement of the carriages.

Description:
This is a nationalization of PCT/FR02/03660 filed Oct. 24, 2002 and published in French. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to roll forming apparatus for fabricating sections, in particular metal sections. 
   2. Description of the Related Art 
   There exists prior art roll forming apparatus that can operate with different sets of pairs of profiling heads according to the type of section to be fabricated. 
   Conventionally, when it is required to change from fabricating one type of section to another, the roll forming apparatus must be stopped and all of the pairs of roll forming heads situated on the roll forming line, i.e. on the path followed by the plate to be roll formed, must be replaced one by one. 
   This takes a very long time and seriously compromises the productivity of the roll forming apparatus. 
   Furthermore, this operation necessitates the use of lifting equipment such as a traveling overhead crane, which is hazardous for personnel and can cause serious accidents. 
   SUMMARY OF THE INVENTION 
   An object of the present invention is to remedy these drawbacks. 
   The above object of the invention is achieved with roll forming apparatus of the type able to operate with different sets of pairs of roll forming heads according to the type of section to be fabricated, characterized in that said pairs of heads are mounted on carriages that can slide both ways in a direction transverse to the roll forming line, so that one set can be replaced by another set with minimum handling. 
   Thanks to these features, it suffices to slide the carriages to install the required set of pairs of roll forming heads, which considerably reduces the down time of the roll forming apparatus and eliminates the risks inherent to the lifting operations used in the prior art. 
   According to other features of the invention: 
   said roll forming apparatus includes carriages supporting a plurality of pairs of roll forming heads belonging to separate sets, 
   said roll forming apparatus includes separate groups of carriages supporting pairs of roll forming heads belonging to different sets, 
   said roll forming apparatus includes first and second sets of pairs of roll forming heads mounted side by side on a first group of carriages and third and fourth sets of pairs of roll forming heads mounted side by side on a second group of carriages independent of said first group, 
   said roll forming apparatus includes at least one double-acting ram for moving each of said carriages, 
   said roll forming apparatus includes two double-acting rams mounted in opposition for moving each of said carriages to place selectively carriages of said first group in one of the following three positions: heads inactive, first set of heads active, second set of heads active, and to place selectively the carriages of said second group in one of the following three positions: heads inactive, third set of heads active, fourth set of heads active, 
   one ram is longer than the other ram to allow for the overall size of a motor for driving pairs of roll forming heads supported by the corresponding carriage, 
   said roll forming apparatus includes means for preventing it from starting before said carriages have reached an alignment enabling the use of one of said sets, 
   said means comprise a plurality of holes formed in said carriages and disposed so as to be aligned when said alignment is reached and a laser beam adapted to pass through all of said holes when said alignment is reached, 
   said carriages are mounted on wheels rolling on rails and said rails comprise recesses disposed to index the positions of said carriages corresponding to the use of each of said sets, 
   said roll forming apparatus includes gantries provided with wedges adapted to support said carriages when said wheels are in said recesses. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other features and advantages of the roll forming apparatus according to the invention will become apparent on reading the following description and examining the accompanying drawings, in which: 
       FIG. 1  is a partial perspective view of roll forming apparatus according to the invention, 
       FIGS. 1   a  and  1   b  show details of  FIG. 1  to a larger scale, 
       FIG. 2  is a perspective view of a carriage of the roll forming apparatus supporting first and second pairs of roll forming heads belonging to respective different sets, 
       FIG. 2   a  shows a detail of  FIG. 2  to a larger scale, 
       FIG. 3  is a bottom view of a portion of the roll forming apparatus shown in  FIG. 1 , and 
       FIGS. 4   a ,  4   b ,  4   c  are diagrams showing three positions that each carriage can occupy. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
   Refer now to  FIG. 1 , which shows that the roll forming apparatus  1  according to the invention comprises a plurality of carriages Ci disposed transversely to the roll forming line indicated by the arrow F. 
   The person skilled in the art will understand that the expression “roll forming line” refers here to the path to be taken by each plate to be roll formed inside the roll forming apparatus  1 , between its entry  3  and its exit  5 . 
   It will be noted that the carriages Ci for which i is even (i=2p) are offset transversely, i.e. in the direction shown by the arrow T perpendicular to the arrow F, relative to the carriages Ci in which i is odd (i=2p+1) for reasons that are explained later. 
   These two groups of carriages are respectively referred to hereinafter as the “even carriage group” and the “odd carriage group”. 
   Refer next to  FIG. 2 , in which it can be seen that each carriage Ci includes first and second pairs P 1   i  and P 2   i  of roll forming heads disposed side by side, i.e. aligned with each other in the direction T. 
   It will be noted that in the present context the expression “roll forming head” means a plurality of discs Di, preferably metal discs, supported by a common shaft Ai, each pair of heads P 1   i , P 2   i  thus being formed of two such pluralities of discs Di, Dj mounted on two parallel shafts Ai, Aj. 
   It will be noted that, for reasons of clarity only, these pairs of heads are not shown in  FIG. 1 . 
   The combination of pairs P 1   i  for which i is even, P 1   i  for which i is odd, P 2   i  for which i is even, and P 2   i  for which i is odd defines four respective sets of pairs of heads, each of which sets produces sections of a particular type. 
   It is therefore clear that the term “set of pairs of heads” refers to all of the pairs of heads placed one after the other in the direction F (see  FIG. 1 ) for producing a predetermined type of section. 
   Each carriage Ci further comprises a gear motor Mi for driving the two pairs of heads P 1   i  and P 2   i  which is supplied with power by appropriate electrical connections, not shown. 
   The discs Di, Dj of each pair of heads turn in opposite directions to confer the required shape progressively on the plates fed to the roll forming apparatus  1 . This is known in the art. 
   Each carriage Ci has wheels Ri on which the carriage slides on corresponding rails RAi (see  FIG. 1 ). 
   As can be seen in the  FIG. 1   a  detail view, the rails RAi comprise recesses CRi adapted to receive the wheels Ri. 
   Referring again to  FIG. 1 , it will also be noted that the roll forming path is delimited by a first gantry Π 1  and a second gantry Π 2 . 
   As can be seen in the  FIG. 1   b  detail view, a plurality of wedges CAi are fixed to the gantries and adapted to cooperate with shoulders Ei formed on each carriage Ci (see the  FIG. 2   a  detail view) when the wheels Ri are in the recesses CRi. 
   It will also be noted (see  FIG. 1 ) that double-acting rams Vi are disposed between each carriage Ci and a fixed support S connected to the floor. 
   Referring next to  FIGS. 3 ,  4   a ,  4   b  and  4   c , it is seen that each carriage Ci is in fact connected to the fixed support S by two double-acting rams V 1   i  and V 2   i  having a common piston Ti. 
   The ram V 1   i  connected to the carriage Ci is preferably longer than the ram V 2   i  connected to the fixed support S. 
   The rams are fed by appropriate hydraulic connections, not shown. 
   Referring more specifically to  FIGS. 4   a ,  4   b  and  4   c , it can be seen that each carriage Ci can occupy three different positions corresponding to different situations of the rams V 1   i  and V 2   i.    
   The position shown in  FIG. 4   a  corresponds to the situation in which the rams V 1   i  and V 2   i  are both extended. 
   The even carriage group is in this position in  FIGS. 1 and 3 . 
   The carriages are therefore as far as possible from the fixed support S, and neither the pairs of heads P 1   i  nor the pairs of heads P 2   i  are in the roll forming area between the gantries Π 1  and Π 2 : these heads are therefore inactive. 
   The position shown in  FIG. 4   b  corresponds to the situation in which the ram V 1   i  is extended and the ram V 2   i  is retracted. 
   The odd carriage group is in this position in  FIGS. 1 and 3 . 
   In this position, the pairs of heads P 2   i  are in the roll forming area: these heads are therefore active. 
   The position shown in  FIG. 4   c  corresponds to the situation in which the rams V 1   i  and V 2   i  are retracted (this position is not shown in  FIGS. 1 and 3 ). 
   In this position, the pairs of heads P 1   i  are in the roll forming area: these heads are therefore active. 
   The roll forming apparatus  1  preferably includes means for preventing it from starting if the carriages Ci have not reached an alignment enabling use of the required set of pairs of heads. 
   As can be seen in  FIGS. 2 and 2   a , such means can comprise holes TRi formed in each carriage Ci and a laser beam RL disposed to pass through the holes TRi of all the carriages Ci when said alignment is reached and thus to illuminate a photoelectric cell CP to authorize starting of the roll forming apparatus. 
   The mode of operation and the advantages of the roll forming apparatus follow directly from the foregoing description. 
   To fabricate metal sections, metal plates are passed from the entry  3  to the exit  5  in the direction F between the gantries Π 1  and Π 2  (see  FIG. 1 ). 
   When the carriages Ci are in the position shown in  FIGS. 1 and 3 , the plates therefore pass between the roll forming heads of the pairs P 2   i  for which i is odd. 
   Thus sections of a first type are obtained. 
   To obtain sections of the type corresponding to the sets of heads P 1   i  in which i is odd, it suffices to place the odd carriage group in the position shown in  FIG. 4   c  and for the even carriage group to remain in the position shown in  FIG. 4   a.    
   To obtain sections of the type corresponding to the sets of heads P 2   i  for which i is even, it suffices to place the odd carriage group in the position shown in  FIG. 4   a  and the even carriage group in the position shown in  FIG. 4   b.    
   To obtain sections of the type corresponding to the sets of heads P 1   i  for which i is even, it suffices to place the odd carriage group in the position shown in  FIG. 4   a  and the even carriage group in the position shown in  FIG. 4   c.    
   As is now clear, the roll forming apparatus  1  can fabricate four different types of section simply by sliding the carriages Ci accordingly before commencing fabrication. 
   It is therefore no longer necessary, as it was in the prior art, to lift each pair of roll forming heads by means of a traveling overhead crane in order to replace it with another pair, which considerably reduces the roll forming apparatus down time and eliminates all risks to personnel associated with lifting operations. 
   It will be noted that because the rams V 1   i  are longer than the rams V 2   i  each pair of heads P 1   i , P 2   i  can be positioned accurately between the two gantries Π 1  and Π 2 , because the additional length of the rams V 1   i  compared to the rams V 2   i  substantially corresponds to the axial length of the gear motor Mi. 
   When it is required to move a carriage Ci from the position shown in  FIG. 4   c  (heads P 1   i  active) to the position shown in  FIG. 4   b  (heads P 2   i  active), the relatively long ram V 1   i  is operated. 
   When it is required to move a carriage Ci from the position shown in  FIG. 4   b  (heads P 2   i  active) to the position shown in  FIG. 4   a  (heads inactive), the relatively short ram V 2   i  is operated. 
   When it is required to move a carriage Ci directly from the position shown in  FIG. 4   c  (heads P 1   i  active) to the position shown in  FIG. 4   a  (heads inactive), the rams V 1   i  and V 2   i  can be operated simultaneously. 
   Of course, to return the carriage to its starting position, the reverse procedure to that just described is carried out. 
   The recesses CRi formed in the rails RAi (see  FIG. 1   a ) index the positions of the carriages Ci to improve further the accuracy of the transverse positioning of the pairs of heads P 1   i , P 2   i.    
   By cooperating with the shoulders Ei (see  FIGS. 1   b  and  2   a ), the wedges CAi completely immobilize each carriage Ci once the wheels Ri are in line with the recesses CRi corresponding to the required positions. 
   The holes GRi and the laser beam RL (see  FIGS. 2 and 2   a ) prevent the roll forming apparatus from starting before all of the carriages Ci have reached the position corresponding to the type of section to be fabricated. 
   Of course, the present invention is not limited to the embodiment described and shown, which is provided entirely by way of illustrative example. 
   For example, the roll forming apparatus according to the invention could comprise only one group of carriages each supporting a plurality of pairs of roll forming heads belonging to separate sets. 
   Likewise, the roll forming apparatus according to the invention could comprise separate groups of carriages each supporting only one pair of roll forming heads belonging to a given set. 
   The invention being thus described, it will be apparent that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be recognized by one skilled in the art are intended to be included within the scope of the following claims.