Abstract:
The invention relates to an automatic device for the production of metal frameworks. The inventive device first places an assembly of longitudinal metal bars ( 5 ) belonging to a framework in horizontal planes and subsequently positions stirrups ( 4 ) around said bars at pre-determined intervals. The invention essentially comprises an assembly of bridge structures ( 1 ) which are defined by pairs of telescopic posts ( 6 ) having end segments from which opposing pairs of horizontal telescopic arms ( 7 ) extend, said arms comprising ends segments ( 9 ) which support the longitudinal bars ( 5 ) of the framework in order subsequently to receive the corresponding stirrups. The stirrups ( 4 ) are first disposed on a table ( 3 ) which travels along guide rails ( 2 ) that are housed centrally between the legs ( 6 ) beneath the arms ( 7 ), such that as the table ( 3 ) advances it positions the stirrups ( 4 ) on the longitudinal bars ( 5 ) and subsequently solders same at the contact points with the different bars.

Description:
OBJECT OF THE INVENTION 
       [0001]    As stated in the title of this descriptive specification, the present invention relates to a device for the automatic production of metal frameworks, the purpose of which is to form a device that will permit the automatic production of metal frameworks. 
         [0002]    It has a dual task, on the one hand that of correctly positioning the metal bars making up the frameworks and on the other the transportation and positioning of the stirrups defining the frameworks, the latter and the former being joined afterwards by means of welding. 
         [0003]    So, the inventive device is intended for producing metal frameworks which are then used in construction, being essentially applicable to columns and walls, for example. 
       PRIOR ART OF THE INVENTION 
       [0004]    There currently exist devices for the production of metal frameworks, some of which facilitate the operation of welding the stirrups to the bars, though the problem of arranging the bars along with the stirrups for the correct production of the frameworks remains unsolved. 
         [0005]    There also exist other devices intended for the production of frameworks, though in these cases the inventions are focused on two specific types of framework, without reaching the point of developing a general purpose device as is proposed in the novel invention. 
         [0006]    On account of all this, metal frameworks for concrete are usually produced manually by fitting the stirrups to longitudinal bars and securing them to the latter with a great deal of patience by means of wire. 
         [0007]    This manual work is excessively slow and costly, since the stirrups have to be distributed on the bars in such a way that they remain spaced out, with a separation that is determined by the manufacturing plans. 
         [0008]    In the same way, there exist automatic devices which permit the bars making up the framework to be positioned at the corresponding separation according to the manufacturing plans. Nevertheless, this equipment fails to solve the problem of having to locate the stirrups around the bars, nor that of their arrangement within the frameworks. 
       DESCRIPTION OF THE INVENTION 
       [0009]    With the aim of achieving the objectives and avoiding the drawbacks mentioned in the above paragraphs, the invention proposes a device for the production of metal frameworks characterised in that it comprises an alignment of bridge structures, beneath which there exists a pair of parallel guides where a table device is provided holding some stirrups in order to locate them strategically around the longitudinal bars arranged in at least two heights, so that they can then be welded to them afterwards. 
         [0010]    Each bridge structure is characterised in that it comprises two vertical telescopic posts and two pairs of horizontal arms facing each other two by two, also with a telescopic arrangement, in such a way that the longitudinal bars of the framework will rest on the end sections of the arms at two different heights depending on the dimensions and the framework to produce. 
         [0011]    The arms incorporate a height adjustment, essentially in order to vary the relative distance between each pair of arms according to the dimensions of the framework that it is wished to obtain, at the same time as said arms are connected in the upper end sections of the posts. 
         [0012]    The table device is characterised in that it comprises an upper platform which includes two parallel vertical plates associated by means of an adjustment mechanism in order to vary the relative distance between them, with the aim of adapting them to the dimensions of the stirrups, which are located precisely between that pair of plates, being arranged one after another until the precise number is achieved for then distributing them perimetrically and around the two groups of bars arranged in horizontal parallel planes, being spaced out from each other by an amount determined beforehand. 
         [0013]    This distribution is done by means of advancing the table device along the guide rails, in such a way that as it advances, it makes intermittent stops were appropriate and deposits a stirrup in the precise location of the bars, enveloping them, in such a way that once the table device has traversed the entire length of the bars, positioning all the stirrups, those stirrups will then proceed to be joined to the bars by means of welding the contact points. 
         [0014]    The table device is also characterised in that it incorporates two rear stops which serve to maintain the position of the stirrups. 
         [0015]    These rear stops are complemented with a thrust mechanism which presses uniformly on the group of stirrups against the said rear stops. 
         [0016]    There also exists a positioning mechanism which permits the stirrups to be located at the intended intervals along the longitudinal bars. 
         [0017]    The table device incorporates a further mechanism for adjustment in order to locate the bars and angled bases at an inclined position when the load of the stirrups is received. 
         [0018]    During the advance of the table device and when it reaches each bridge structure, the telescopic arms thereof withdraw and place themselves in a folded position, in such a way that the bars cease to rest for a period of time on that specific pair of arms until the table device completely exceeds the vertical plane of the respective bridge structure, returning afterwards to the unfolded active position in which the bars again rest on the end sections of the arms. 
         [0019]    Said lower base furthermore incorporates a characteristic first group of sensors corresponding to each bridge structure so that the arms fold every time the table device reaches each of the said bridge structures. 
         [0020]    The lower base incorporates a second characteristic group of sensors in the actual guides for at all times controlling the exact position of the table, and thereby locate each stirrup in the desired positions determined beforehand along the longitudinal bars resting on the successive arms. 
         [0021]    Below, in order to facilitate a better understanding of this specification and forming an integral part thereof, some figures are attached in which, on an illustrative rather than limiting basis, the most characteristic details of the invention have been represented. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0022]    FIG.  1 .—Shows a perspective view of the automatic device for production of metal frameworks, the object of the invention. 
           [0023]    FIG.  2 .—Shows a profile view of the inventive device. 
           [0024]    FIG.  3 .—Shows a perspective view of the application of the inventive device. 
           [0025]    FIG.  4 .—Shows a view of part of the device. This basically concerns one of the various vertical telescopic posts, from whose highest section extends a pair of horizontal arms also with telescopic adjustment. 
           [0026]    FIG.  5 .—Shows a perspective view of a table device adjustable in height and with various mechanisms. Said device is responsible for receiving and facilitating the location of some stirrups along some longitudinal bars previously arranged in horizontal planes forming part of the frameworks. 
           [0027]    FIG.  6 .—Shows another perspective view of the table. 
           [0028]    FIG.  7 .—Shows a front view of the table. 
           [0029]    FIG.  8 .—Shows a view of a mechanism for hauling the table along some lower guide rails. 
           [0030]    FIG.  9 .—Shows a perspective view of the end sections of the telescopic arms incorporating certain elements for grasping and locating the longitudinal bars. 
           [0031]    FIG.  10 .—Shows a perspective view of a relative adjustment mechanism between pairs of arms. 
       
    
    
     DESCRIPTION OF THE PREFERRED FORM OF EMBODIMENT 
       [0032]    Considering the numbering adopted in the figures, the automatic device for production of frameworks is defined starting from an alignment of bridge structures  1 , arranged centrally beneath which are a pair of parallel continuous guide rails  2  on which travels a table device  3 , adjustable in height. 
         [0033]    This table device  3  receives some stirrups  4  in order afterwards to locate them strategically around two groups of longitudinal bars  5  positioned in two different planes, so as afterwards to weld said stirrups  4  to the bars  4  at their contact points, all this by means of an automatic process governed from a control cabinet  34 . 
         [0034]    The bridges structures  1  comprise a pair of vertical telescopic posts  6  with height adjustment and two pairs of horizontal telescopic arms  7  facing each other two by two, which extend from the uppermost end sections  8  of the posts  6 . The longitudinal bars  5  rest on the end sections  9  of the arms  7  at two different heights according to the dimensions of the framework to produce. 
         [0035]    So, first a group of bars will be laid on the end sections  9  of the lowermost arms  7  with the upper arms  7  remaining folded. The upper arms are then arranged in the unfolded position in order to locate the second group of bars  5  on the end sections  9  of the upper arms  7 . 
         [0036]    These end sections  9  of the horizontal arms  7  incorporate certain retractable gripping hooks  10  in order to grasp and locate the bars correctly at the desired distance when they are resting of those end sections  9 . These gripping hooks  10  extend from an elongated channel  11 , in such a way that the adjustment in distance of the hooks  10  can be done either manually or automatically. 
         [0037]    The gripping by means of the respective hooks  10  can be done in different positions in such a way that they can be hidden or otherwise, both for withdrawing the arms  7  and as a function of the number of bars  5  which the framework is going to have. All the movements of the grips will be able to be done manually or automatically. 
         [0038]    The arms  7  incorporate a height adjustment mechanism for being able to vary the relative distance between each pair of arms  7 , according to the dimensions of the framework it is wished to obtain. 
         [0039]    This adjustment mechanism basically consists of some rails  12  located in the end sections  8  of the vertical posts  6 , in such a way that travelling in those rails  12  are some guide elements  13  coupled to a support  14  integral with each telescopic arm  7 . The vertical displacement of the support  14  of each arm  7  is done by means of any suitable motor element. 
         [0040]    The table device  3  in principle comprises an upper platform  15  supported by two pairs of crossed legs  16  with a linkage  17  at their cross-over points so that the height of the table can be varied according to need. In order to make the height adjustment possible, provided in the linkage of the legs with the platform  15  via its lower face are some parallel guides  18  which permit the upper ends of the legs  16  to slide until the table  3  reaches the desired height. 
         [0041]    Moreover, the upper platform  15  of the table  3  incorporates two parallel plates  19  in vertical planes associated by means of a worm gear  20  provided beneath the platform  15  in order to adjust the distance between them so as to adapt them to the dimensions of the stirrups  4 , which are located precisely between that pair of plates  19 , being arranged one after another in successive vertical planes until the precise number is achieved for then distributing them perimetrically and around the two groups of bars  5  arranged in horizontal parallel planes, being spaced out from each other by an amount determined beforehand. 
         [0042]    This distribution is done by means of advancing the table device  3  along the guide rails  2 , in such a way that as it advances, it makes intermittent stops where appropriate and deposits a stirrup  4  in the precise location of the bars  5  enveloping them, in such a way that once the table device  3  has traversed the entire length of the bars  5 , positioning all the stirrups  4 , those stirrups  4  will then proceed to be joined to the bars  5  by means of welding the contact points of these with respect to the stirrups  4 . The parallel plates  19  includes some angled base  21 . 
         [0043]    The displacement of the table assembly  3  is done by means of a hauling mechanism which basically consists of a chain  22  associated with some rollers  23  fitting in the guide channels  2 , where some wheels  24  of the table  3  are also to be found, which take the thrust of the rollers  23  when the hauling mechanism acts in order to displace the table  3 . 
         [0044]    The guide channels  2  incorporate some lateral grooves  25  in which fit some intermediate sections of the rollers  23 , which are connected to the chain  22  from the outside of the guide channels  2 . 
         [0045]    The table device  3  also incorporates two rear stops  26  which extend perpendicularly from the angled bases  21  and serve to maintain the position of the stirrups  4 . 
         [0046]    These rear stops  26  are complemented with a thrust mechanism  27  which presses uniformly on the group of stirrups  4  against the said rear stops  26 . 
         [0047]    There also exists a positioning mechanism  28  which permits the stirrups  4  to be able to be located at the intended intervals along the longitudinal bars  5 . 
         [0048]    The table device  3  incorporates a further mechanism for adjustment in order to locate the plates  19  and angled bases  21  at an inclined position when the load of the stirrups  4  is received from a raised zone above that upper platform  15  and parallel plates. For this, the two sets of plates  19  and angled bases  21  are linked by means of a rear hinge  29  in the platform  15  of the table  3 . 
         [0049]    The location of the stirrups  4  between the parallel plates  19  of the upper platform  15  can be done manually as well as automatically. 
         [0050]    The positioning mechanism  29  is associated with the front part of those two parallel plates  19 , in that case remaining contiguous with the load zone in order later on to permit and facilitate the positioning of the stirrups  4  along the longitudinal bars  5 . 
         [0051]    During the advance of the table device  3  and when it reaches each bridge structure  1 , the telescopic arms  7  thereof withdraw and place themselves in a folded position, in such a way that the bars  5  cease to rest for a period of time on that specific pair of arms  7  until said table device  3  completely exceeds the vertical plane of the respective bridge structure  1 , returning afterwards to the unfolded active position in which the bars  5  again rest on the end sections of the arms  7 . 
         [0052]    The guide rails  2  are arranged on a lower base  30  which also incorporates two alignments of connection elements  31  of the vertical posts  6 . 
         [0053]    Said lower base  30  furthermore incorporates a characteristic first group of sensors  32  corresponding to each bridge structure  1  so that the arms  7  fold every time the table device  3  reaches each of the said bridge structures  1 . These sensors are specifically located between the guides by way of rails  2 . 
         [0054]    The lower base  30  incorporates a second characteristic group of sensors  33  in the actual guides  2  for at all times controlling the exact position of the table  3 , and thereby locate each stirrup  4  in the desired position determined beforehand along the longitudinal bars  5  resting on the successive arms  7 . 
         [0055]    The production of the framework is a totally automatic process of high precision and good functioning governed from the control cabinet  34  provided for example in the zone of the lower base  30 , as shown in the figures.