WO2005084848A1

WO2005084848A1 - Machine to produce reinforcement cages, and relative production method

Info

Publication number: WO2005084848A1
Application number: PCT/IB2005/000519
Authority: WO
Inventors: Giorgio Del Fabro; Marcello Del Fabro
Original assignee: M.E.P. Macchine Elettroniche Piegatrici Spa
Priority date: 2004-03-02
Filing date: 2005-03-01
Publication date: 2005-09-15
Also published as: EP1720672A1

Abstract

Machine (10) to produce reinforcement cages (11) consisting of a plurality of longitudinal bars (12) and a clamping round piece (13) wound around and fixed to the longitudinal bars (12). The machine (10) comprises in succession a fixed head (16) provided with rotary members (25) with which the ends of the longitudinal bars (12) are associated, a motorized movable head (17) supporting welding elements (31) to weld the clamping round piece (13), and at least a supporting trolley (19, 20) which supports the segments of the longitudinal bars (12) on which the clamping round piece (13) has not yet been deposited. Each of the supporting trolleys (19, 20) comprises a rotatable disk (42, 142) arranged substantially coaxial to the rotary members (25), and provided with a plurality of radial grooves (43, 44; 56, 57) of a width substantially mating with the transverse section of the longitudinal bars (12) and having a loading aperture facing towards the outside. Inside each of the radial grooves (43, 44; 56, 57) at least one of the longitudinal bars (12) is inserted from one side, and guided to its correct radial positioning.

Description

"MACHINE TO PRODUCE REINFORCEMENT CAGES, AND RELATIVE

PRODUCTION METHOD" * * * * * FIELD OF THE INVENTION The present invention concerns a machine to make reinforcement cages, particularly cylindrical but also square or polygonal in general, formed by a plurality of longitudinal bars around which a metal clamping round piece is wound and welded in a coil. The cages are normally used in the building trade, for example to make columns of reinforced concrete. The present invention also concerns the method to make said reinforcement cages by means of the aforesaid machine. BACKGROUND OF THE INVENTION A machine is known for making cylindrical reinforcement cages of the type indicated above, comprising a first, longitudinally fixed head provided with a rotary plate on which the ends of the longitudinal bars are fixed, a second head able to slide longitudinally with respect to the fixed head, on which the elements for welding the clamping round piece in a coil are mounted, and a plurality of support means, able to slide along the whole length of the longitudinal bars, and able to support the segments of bars on which the metal clamping round piece has not yet been fixed. The coordinated action between the rotation of the rotary plate and the sliding of the second head determines the depositing of the metal round piece in a coil. This known machine, although it has a longitudinal bulk limited substantially to the length of the reinforcement cage to be made, needs to load the longitudinal bars by inserting them frontally for the whole of their length, which can be about 12 and more, both through the support means and also through the second head, until their ends are fixed on the rotary plate of the first fixed head, in order to ensure the correct positioning thereof. This disadvantage entails not only an increase in the setting up times and the production times, but also the need to provide a store of longitudinal bars, located in line with the machine, with a consequent increase of the bulk in length necessary to install the whole machine. Another disadvantage of known machines is the need, once the cage has been made and discharged, to equip the machine manually, in order to perform the following cycle, repositioning the second head and the support means at the desired distances. A machine for making reinforcement cages is also known comprising a first head, movable longitudinally and provided with a rotary plate on which the ends of the longitudinal bars are fixed, and a plurality of fixed support means, one of which is provided with the elements to weld the round piece. The remaining fixed support means have a plurality of spokes, very distant from each other, and defining a corresponding plurality of substantially open sectors, into which the bars are loaded without being in the least guided and/or positioned, so that their position, after loading, is unstable and not correctly defined. The coordinated action of the rotation of the rotary plate and the longitudinal sliding of the movable head, as it moves away from the fixed support means, determines the traction of the longitudinal bars and the deposition thereon of the metal round piece in a coil. This last type of machine, although it allows the longitudinal bars to be loaded from the side, has the disadvantage, however, that it must in any case provide a travel of its movable head at least equal to the length of the reinforcement cage, therefore the whole machine has a total length which is at least double the length of the reinforcement cage. One purpose of the present invention is to perfect a machine to make reinforcement cages which has a total bulk substantially equal to, or slightly more than, the length of the reinforcement cage to be made, which allows a lateral loading of the longitudinal bars, and which allows to keep the bars, when they have been loaded and before they have been welded, in a stable position, coherent with the position assumed in the final configuration of the cage. Another purpose of the present invention is to make a machine which does not need manual equipping steps after the cage has been made and discharged. Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state, of the art and to obtain these and other purposes and advantages. SUMMARY OF THE INVENTION The present invention is set forth and characterized in the main claims, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea. In accordance with the above purposes, a machine according to the present invention is applied to make reinforcement cages consisting of a plurality of longitudinal bars and at least a metal round piece wound and welded in a coil around the longitudinal bars. The machine according to the invention comprises at least a first fixed head provided with a rotary plate with which the ends of the longitudinal bars are associated, a second movable head, able to slide longitudinally with respect to the fixed head, and on which the means to weld the metal round piece are mounted, and at least a support means, able to slide along the longitudinal bars and able to support at least the segments of longitudinal bars on which the metal round piece has not yet been fixed. According to a characteristic feature of the present invention, each support means comprises a rotatable disk arranged coaxial with the rotary plate of the fixed head, and provided with a plurality of radial grooves, of a size substantially mating with the transverse section of said longitudinal bars, and including an insertion aperture facing towards the outside, inside each of which at least one of the longitudinal bars is able to be inserted laterally and guided to its correct radial positioning. The machine according to the present invention thus has the second head and the support means that have a longitudinal travel substantially limited to the length of the reinforcement cage to be made and, at the same time, allows a guided lateral loading of the longitudinal bars onto the machine, making possible a sequential loading with the desired number of bars, by rotating on each occasion the rotatable disk by the desired angle, from a store arranged at the side of the machine itself. In this way, the bulk in length of the machine is limited substantially to a little more than the length of the longest cage that can be obtained. Moreover, since the radial grooves are of a size substantially mating with that of the transverse section of the longitudinal bars inserted laterally into them, the latter are guided and maintained in a substantially correct radial position, also during the longitudinal sliding of the second head and the support means. Another advantage of the machine according to the present invention is that, by loading the longitudinal bars laterally, the times and the difficulties of the workers responsible for loading the bars are considerably reduced, since the laborious operation of inserting one bar at a time from the front through all the components of the machine is avoided. According to a variant, guide means are provided on the support means, able to guide each individual longitudinal bar when it is loaded inside the respective radial groove, so as to further ensure the correct positioning of each longitudinal bar loaded. According to another variant, stop means are present along the radial groove, in an adjustable position, in order to stop the relative bar in the desired radial position. According to another variant, on the periphery of the rotatable disk, in correspondence with each radial groove, a closing means is provided able to allow the loading of the longitudinal bars inside the respective groove and, at the same time, to prevent the accidental escape of the latter, for example when the relative rotatable disk is rotated to allow the loading of a subsequent longitudinal bar. In another preferential form of embodiment of the present invention, the rotatable disk is selectively interchangeable with others having grooves of different shapes and/or sizes, so as to allow to make reinforcement cages of various format, weight and number and size of longitudinal bars . After loading onto the support means, the ends of the bars are affixed to the rotary plate of the fixed head, after being inserted into the movable head. In this way, starting the rotation of the rotary plate, and starting the longitudinal sliding of the second moveable head along the bars, the metal round piece is progressively arranged in a coil and welded onto the longitudinal bars . In one embodiment of the present invention, the moveable head comprises first attachment means which connect it to the support means , so that said two elements move in a first direction of sliding, for example the working direction, keeping the reciprocal distance constant. Thanks to the attachment means, during the steps of forming the cage, the moveable head as it advances pushes the support means along the first direction, until the formation of the cage is finished. According to a variant, the moveable head and the support means slide on rails along which at least a release element is arranged, able to act on the attachment means in order to determine the selective detachment of each of the support means and the moveable head. This selective detachment advantageously occurs when the moveable head is in a position near the end of the completed cage and the support means is already beyond said end, so as to reduce, in the final step, the space needed to free the finished cage and to eliminate the interference between the finished cage and the moveable head, to allow the discharge thereof and to limit the maximum bulk of the whole machine. According to another variant, wherein two or more support means are provided, distanced along the longitudinal bars, each support means is provided with its own attachment means. As a result, when the first support means, due to the effect of the thrust exerted by the moveable head, comes into contact with an adjacent support means, it is attached thereto and thrusts it until the cage is complete. In this case, specific automatic release elements are provided, which act, in the return travel, on the relative clamping means, so as to determine the release detachment of each support means in correspondence with its position of departure. In this way, at the conclusion of every cage-making cycle, the machine according to the invention is equipped r-apidly and in a completely automatic manner. BRIEF DESCRIPTION OF THE DRAWINGS These and other characteristics of the present invention will become apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein:

— fig. 1 is a three-dimensional view of an example of a cylindrical reinforcement cage made with the machine according to the present invention; — figs. 2 to 7 show, with a lateral, schematic view, a sequence of the operating steps of a machine to make cages according to the present invention;

— fig. 8 is a view from VIII of an enlarged detail of the machine in fig. 2; — fig. 9 is a view from IX of an enlarged detail of the machine in fig. 2;

— fig. 10a is a view from X of an enlarged detail of the machine in fig. 2;

— fig. 10b shows a variant of fig. 10a; — figs. 11a, lib and lie show in sequence three operating steps of the machine in fig. 2 during the second operating step;

— figs. 12a, 12b and 12c show in sequence three operating steps of the machine in fig. 2 during the third operating step;

— figs. 13a, 13b and 13c show in sequence three operating steps of the machine in fig. 2 during the fifth operating step; - figs. 14a, 14b and 14c show in sequence three operating steps of the machine in fig. 2 during the sixth operating step. DETAILED DESCRIPTION OF A PREFERENTIAL FORM OF EMBODIMENT With reference to the attached figures, a machine 10 according to the present invention is applied to make a reinforcement cage 11, in this case cylindrical, for example of the type used in the building trade in order to make columns of reinforced concrete. The cylindrical cage 11 (fig. 1) comprises a plurality of longitudinal bars 12, in this case six, arranged parallel with each other along an ideal circumference, shown by a line of dashes, and angularly separated from each other by an angle of about 60°. The cylindrical cage 11 also comprises a clamping round piece 13 wound and welded in a coil around the longitudinal bars 12, so as to join the bars 12 to each other and define a cylindrical structure. The machine 10 according to the present invention (fig. 2) comprises a base frame 15, on which are mounted, starting from left to right, a first fixed head 16, a second head 17 able to slide longitudinally, and two support means consisting in this case of a first 19 and a second 20 trolley. At the side of the base frame 15 a store 21 is provided for pre-cut longitudinal bars 12, by means of which, as we shall see later, the longitudinal bars 12 are fed in sequence to the machine 10. The base frame 15 comprises two rails 22, which run substantially for the whole length of the machine 10, on which the second head 17 and the two trolleys 19 and 20 slide, and four arms 23, arranged between the two rails 22, and able to support the cylindrical cage 11 which is progressively formed. To be more exact, the four arms 23 are independently moveable by means of respective linear actuators 24, between a first operating position wherein they are angled upwards with respect to the plane on which the rails 22 lie, and a second retracted position wherein they are substantially parallel to the plane on which the rails 22 lie. Outside the rails 22 two cam elements are also provided, a first 18 and a second 28, arranged in pre-determined positions, and possibly modifiable according to the length of the cage to be made; the functions of these will be described in detail later. The first head 16 (fig. 8) substantially comprises a motorized rotary plate 25, provided with a plurality of clamps 26, in this case six, on each of which one end of at least a respective longitudinal bar 12 can be fixed. Each clamp 26 advantageously cooperates with a fluid-dynamic actuator , of a known type and not shown in detail, able to be selectively activated so as to determine the attachment of the respective longitudinal bar 12 to the rotary plate 25. Each clamp 26 is mounted able to slide inside a respective radial eyelet 27 made on the rotary plate 25, so that its position with respect to the latter can be modified as desired, for example according to the diameter of the cage 11 to be made. The second head 17 comprises a motorized carriage 29 (fig. 9) mounted able to slide on the rails 22, a feed device 30 to feed the clamping round piece 13, and one or more welding devices 31, able to weld the clamping round piece 13 to the longitudinal bars 12. On the motorized carriage 29 an idle rotor 32 is mounted, arranged substantially coaxial with the rotary plate 25, and provided with a plurality of guide and positioning eyelets 33, which are equal in number to the longitudinal bars 12 provided, and arranged annularly with a diameter equal to the diameter of the cylindrical cage 11 to be made. The guide and positioning eyelets 33 are able to guide the longitudinal bars 12 against the rotary plate 25, in order to fix the ends to the latter by means of the clamps 26. In this way, the rotation of the plate 25 is transmitted, by means of the longitudinal bars 12, to the eyelets 33 and consequently to the idle rotor 32. On a front surface of the motorized carriage 29, that is, the surface facing towards the first trolley 19, in proximity with the rails 22, an attachment bar 34 is pivoted (figs. 12a, 12b, 12c, 13a, 13b and 13c) having a length of some tens of millimeters and able to be attached to a mating attachment block 49 provided on the first trolley 19. Since the first trolley 19 is mounted idle on the rails 22, the attachment bar 34, when constrained, allows the second head 17 to push, or pull, the first trolley 19, keeping the distance between the two constant during the movement steps. This constraint of distance allows to keep the longitudinal bars 12 correctly positioned during the movement of the second head 17 and the first trolley 19. The attachment bar 34 comprises, laterally, a wheel 52 able to cooperate with the first cam element 18 so as to determine, in one step of the work cycle, the detachment of the bar 34 from the relative attachment block 49, in order to release the second head 17 and the first trolley 19 from each other. Moreover, in proximity with its front terminal zone, the attachment bar 34 comprises a shaped surface 53 able, during the repositioning steps, to allow the attachment of the bar 34 and the relative attachment block 49, in order to restore the constraint between the two elements during the return travel. The feed device 30 (fig. 9) is of a substantially known type, and comprises a plurality of drawing rollers 35 mounted on the motorized carriage 29, and able to feed continuously the clamping round piece 13 arriving for example from a remote coil, not shown here, so that said round piece 13 is guided with a direction substantially tangent to the longitudinal bars 12 arranged inside the guide and positioning eyelets 33. The welding device 31, also of a substantially known type, is of the tracking type and comprises a supporting arm 36 mounted on the motorized carriage 29, above the drawing rollers 35, and on which a welding trolley 37 slides. The trolley 37 has two guide wheels 39, arranged aligned with each other and able to ride over the clamping round piece 13, immediately upstream and immediately downstream of the point of tangency of the latter with the longitudinal bars 12. The welding trolley 37 also comprises a welder 40, for example a continuous wire welder, arranged laterally and between the two guide wheels 39, so as to weld the clamping round piece 13 to a longitudinal bar 12, in proximity with the point of tangency between the two. The two trolleys 19 and 20 have some components substantially equal and therefore, to simplify the description, we shall now describe in detail only the one identified in the drawings by the reference number 19. The first trolley 19 (fig. 10a) comprises a vertical structure 41 able to slide idly with respect to the rails 22, and a disk or capstan 42, mounted rotatable on the vertical structure 41. The capstan 42 is arranged substantially coaxial both with the rotary plate 25, and also with the idle rotor 32, and comprises a plurality of radial grooves 43 and 44, open towards the outside and each one able to house a respective longitudinal bar 12. In this case, two series of radial grooves 43, 44 are provided, respectively, a first series and a second series. The first series, used in the example shown, has deep radial grooves 43, which allow to make cylindrical cages 11 of a limited diameter, while the second series has radial grooves 44 arranged alternately, and less deep, with respect to those of the first series, and more specific for making cylindrical cages 11 with a larger diameter. The series of radial grooves 43 and 44 have a width size mating with the transverse section of the longitudinal bars 12 to be inserted laterally inside them, so as to guide the longitudinal bars 12 to their correct positioning, and keep them there, preventing random lateral oscillations thereof, particularly during the rotation of the relative capstan 42. On the capstan 42 a plurality of closing levers 58 are also pivoted, each one arranged in correspondence with a relative loading aperture of the radial grooves 43 and 44. Each of the closing levers 58 has a first end pivoted to the capstan 42, and a second free end which rests, at least when the closing lever 58 is in the lower semi- circumference of the capstan 42, on the pivoted end of the adjacent closing lever 58. In this way, the longitudinal bars 12 can be inserted laterally inside the respective radial grooves 43 and 44, by displacing the relative closing lever 58 which does not create any interference. When the capstan 42 is progressively rotated to perform the sequential loading of the various bars 12, and the bars 12 already loaded are in position, for example , in its lower semi-circumference, which would cause them to escape from the relative groove 43, 44 due to the force of gravity, the presence of the closing levers 58 stops the travel of the bars 12 and prevents them escaping. According to the variant shown in fig. 10b, the capstan 142 has two series of radial grooves indicated by the reference numbers 56 and 57, and a plurality of closing levers 58 of the type similar to those described above. Also in the embodiment shown in fig. 10b, the radial grooves 56 and 57 have a lateral size substantially mating with the transverse section of the longitudinal bars 12 inserted inside them. To be more exact, the grooves 57 have a lateral size mating with the number of adjacent longitudinal bars 12 arranged inside them. In this case, the grooves 56 have a constant transverse section along their whole length, while the grooves 57 have at least a wider segment, so as to allow the possible positioning inside them of two or more adjacent longitudinal bars 12. Fig. 10b also shows, with a double-dot/dash line, a retaining bar 59, curved and arranged fixed in correspondence with the lower semi-circumference of the capstan 142, so as to prevent the longitudinal bars 12 loaded laterally into the radial grooves 56 and 57 from being displaced radially, due to the effect of gravity, beyond a certain diameter. In this way, the correct positioning of the longitudinal bars 12 is guaranteed during the rotation of the capstan 142, and the movement of the respective first trolley 19 and/or the second trolley 20 . In both the aforesaid embodiments with capstans 42, 142, the vertical structure 41 is open laterally on the side of the store 21, by means of an aperture 45, so as to allow the lateral loading of the longitudinal bars 12 housed in the store 21, inside the respective radial grooves, for example those indicated by the number 43 in fig. 10a. Advantageously, a plurality of inclined guides 46 are provided, which form a slide between the store 21 and the aperture 45, and allow each individual longitudinal bar 12 to be inserted by falling inside the respective radial groove 43. Each inclined guide 46 advantageously rotates between a loading position, shown in figs. 10a and 10b, and a position near the side of the store 21. Moreover, a door 47 is pivoted on the vertical structure 41, in correspondence with the aperture 45, and is able to allow the longitudinal bars 12 to enter inside the respective radial grooves 43, but not to exit therefrom accidentally, into the loading zone. In the lower part of the vertical structure 41 of the first trolley 19 there is the aforesaid attachment block 49 and, on the surface facing towards the second trolley 20, an attachment pin 51, able to selectively cooperate with a respective attachment hook 50, pivoted in a mating position in the lower part of the vertical structure 41 of the second trolley 20, in order to cause the attachment of the two. The attachment hook 50 comprises an inclined surface 54, arranged below and able to cooperate with the cam element 28 so as to determine the detachment of the second trolley 20 from the first trolley 19. On the second trolley 20 a rubber shock absorber 55 is also provided, parallel to the attachment hook 50, against which the thrust of the first trolley 19 is made during the operating steps. The machine 10 to make reinforcement cages 11 as described heretofore functions as follows. Firstly, the longitudinal bars 12 are loaded onto the machine 10, making them slide along the inclined guide 46 and inserting them from, the side into the respective radial grooves 43 or 44, 56 or 57 of the capstans 42, 142, of the two trolleys 19 and 20. Advantageously, the longitudinal bars 12 are arranged inside the store 21 so that their front end is arranged so as not to interfere with the second head 17 during loading. After every loading of one or more longitudinal bars 12, the capstans 42, 142 are rotated by the angle , so as to allow a subsequent bar 12 to be inserted laterally, and so on until, in this case, six longitudinal bars 12 have been completely loaded. The value of the angle α can be inserted by the operator into a command unit of the machine 10, during the start-of- cycle step, so that the capstans 42, 142 are automatically positioned and on each occasion in the correct angled positions, according to the type of cage 11 and the number of longitudinal bars 12. Every time a longitudinal bar 12 enters into the lateral aperture 45 it temporarily raises the door 47 and the corresponding closing lever 58. When the loading of the longitudinal bars 12 onto the machine 10 is complete, they are moved axially by some tens of millimeters so as to insert them through the guide and positioning eyelets 33 of the idle rotor 32, and take their front ends into cooperation with the clamps 26 of the rotary plate 25. This axial movement of the longitudinal bars 12 can be performed, according to a variant not shown here, by means of automatic axial movement means of a known type, such as for example rollers, pincers, thrusters or other. At this point the longitudinal bars 12 are arranged substantially parallel to each other and, in this case, separated angularly by 60° from each other. Once this arrangement of the longitudinal bars 12 has been achieved, the feed device 30 is activated, so as to take one end of the clamping round piece 13 into correspondence with one of the longitudinal bars 12. This end of the clamping round piece 13 is welded by means of the welding device 31 to the longitudinal bar 12 and then the rotary plate 25 is made to rotate. The rotation of the rotary plate 25 entails a relative winding of the clamping round piece 13 around the longitudinal bars 12. During this rotation, the clamping round piece 13 is progressively welded, by means of the welding device 31, to the longitudinal bars 12 that pass through the point of tangency. In this initial step the second head 17 remains longitudinally still, so that the clamping round piece 13 winds for at least a complete turn remaining substantially on a single plane transverse to the longitudinal bars 12. It is not excluded that the first welding operations can be performed manually by the operator. At this point the second head 17 is commanded to advance longitudinally in a first operating direction, that is, away from the first fixed head 16 (fig. 2). This advance of the second head 17, in association with the rotation of the longitudinal bars 12 and the tangential feed of the clamping round piece 13, determines a substantially coil-like positioning of the latter with respect to the longitudinal bars 12, and the welding thereon of the clamping round piece 13 by means of the welding device 31. It is clear that the movement of the second head 17 and the rotation of the plate 25 have their own independent speed, so as to be able to modify as desired the parameters for making the cylindrical cage 11. As it advances, the second head 17 progressively thrusts the first trolley 19, by means of the attachment bar 34 which, at the beginning of the operating cycle, is attached to the mating attachment block 49. When the first trolley 19 comes into proximity with the second trolley 20, the attachment hook 50 of the latter is taken into cooperation with the respective attachment pin 51, thus determining the constraint between the two trolleys 19 and 20, and their advance due to the thrust imparted by the second head 17. To be more exact, as shown in figs. 11a to lie, the attachment hook 50 is partly raised due to the effect of the contact of its inclined surface 54 with the cam element 28, and the thrust of the first trolley 19 is made against the shock absorber 55. In this way, the inclined surface 54 of the attachment hook 50 is progressively freed from the cam element 28, until it falls and is attached to the relative attachment pin 51 made on the first trolley 19. The arms 23 are initially in their lowered, retracted position and, once the second head 17, possibly attached to one or both trolleys 19 and 20, passes one of said arms 23, it moves to its high operating position in order to support the already formed part of the cylindrical cage 11 (fig. 3). Advantageously, sensor means are provided, of a known type and not shown here, able to detect the position of the second head 17 and, depending on said position, to command the relative linear actuators 24 of each arm 23. When the second head 17, advancing, arrives in proximity

--with the terminal part of the longitudinal bars 12 (fig. 4), the wheel 52 of its attachment arm 34 interferes with the cam element 18 (figs. 12a, 12b and 12c), which determines the detachment of the attachment bar 34 and the relative attachment block 49. In this way, the two trolleys 19 and 20 stop, since they are no longer thrust by the second head 17, and the latter advances alone until it comes next to the first trolley 19. Consequently, the head 17 and the trolleys 19 and 20 are compacted in a position that does not interfere with the formed cage 11, and the spaces occupied by the machine 10 beyond the length of the completed cage 11 are reduced to a minimum. When a desired number of coils of the round piece 13 have been deposited and welded, the second head 17 is stopped. Advantageously the last coils are deposited on a plane substantially transverse to the longitudinal bars 12. The cylindrical cage 11 thus formed is released from the first head 16 and discharged by means of the simultaneous movement of the arms 23 into their retracted position (fig. 5). Once the cylindrical cage 11 has been discharged, the second head 17 is made to retreat in a repositioning direction (fig. 6), opposite the operating direction, so as to reset the machine 10 in order to make a new cylindrical cage 11. During this movement of retreat, the attachment bar 34 slides resting above the attachment block 49, until the shaped surface 53 of the bar 34 contacts the latter (figs. 13a, 13b and 13c). In this condition the attachment bar 34 rotates upwards allowing the wheel 52 to pass over the cam element 18. When the shaped surface 53 finishes its contact with the attachment block 49, the attachment bar 34 rotates downwards, attaching itself to the block 49. In this way, and from this point onwards, the movement of the second head 17 in the repositioning direction causes the drawing of the two trolleys 19 and 20 which have remained attached to each other. The trolleys 19 and 20 become detached from each other once the inclined surface 54 of the attachment hook 50 contacts the cam element 28 (figs. 14a, 14b and 14c). In this way, the equipping of the machine 10 in order to perform a new cycle is performed simply, quickly and completely automatically. It is clear, however, that modifications and/or additions of parts or steps, may be made to the machine 10 and relative method as described heretofore, without departing from the field and scope of the present invention. For example, it comes within the field of the present invention to provide a number of supporting trolleys other than two, according to the length of the longitudinal bars 12, or the type of cylindrical cage 11 to be made. It also comes within the field of the present invention to provide that the cam elements 18 and 28 can be of the removable type, so as to be able to position them as desired along the rails 22, according to the length of the cage 11 to be made. Moreover, the attachment bar 34 could be of the telescopic type so as to select the distance, which then, during the work cycle, remains fixed, to be kept between the second head 17 and the first trolley 19. It also comes within the field of the present invention to provide that the attachment and detachment of the second head 17 and the two supporting trolleys 19 and 20 can occur by means of electronically commanded magnetic means. It is also clear that, although the present invention has been described with reference to specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of machine to make cylindrical cages, and the relative production method, all of which shall come within the field and scope of the present invention.

Claims

1. Machine to produce reinforcement cages (11) consisting of a plurality of longitudinal bars (12) and at least a clamping round piece (13) wound around and fixed to said longitudinal bars (12), said machine comprising in succession at least a fixed head (16) provided with rotary means (25) with which the ends of said longitudinal bars (12) are associated, a motorized movable head (17) supporting welding means (31) to weld said clamping round piece (13), and at least a support means (19, 20) able to support the segments of said longitudinal bars (12) on which said clamping round piece (13) has not yet been deposited, characterized in that each of said support means (19, 20) comprises at least a rotatable disk (42, 142) arranged substantially coaxial with said rotary means (25), and provided with a plurality of radial grooves (43, 44; 56, 57) of a width substantially mating with the transverse section of said longitudinal bars ( 12 ) and having a loading aperture facing towards the outside, inside each of said radial grooves (43, 44; 56, 57) at least one of said longitudinal bars ( 12 ) is able to be inserted from one side, and guided to its correct radial positioning.

2. Machine as in claim 1, characterized in that on the periphery of said rotatable disk (42, 142), in correspondence with each of said radial grooves (43, 44; 56, 57) there are closing means (58) able to allow the free loading of the longitudinal bar (12) inside the respective groove (43, 44; 56, 57) when the relative rotatable disk (42, 142) is in the loading position, and to prevent the accidental exit of said longitudinal bar (12) when the rotatable disk (42, 142) has moved to a position other than the loading position.

3. Machine as in claim 2, characterized in that each of said closing means comprises a lever (58) arranged in correspondence with the aperture of the corresponding radial groove (43, 44; 56, 57) and comprising a first end pivoted to said rotatable disk (42, 142) and a second free end which rests, at least when said closing lever (58) is in correspondence with a lower part of said rotatable disk (42, 142), on the pivoted end of the adjacent closing lever (58), thus preventing the exit of the relative longitudinal bar (12) from the radial groove (43, 44; 56, 57).

4. Machine as in claim 1, characterized in that said rotatable disk (42, 142) is associated with automatic means able to make it rotate for a desired angle (oc), in order to load a plurality of longitudinal bars ( 12 ) into said radial grooves (43, 44; 56, 57) according to the shape of said cage (11) and the number of longitudinal bars (12) that make it up.

5. Machine as in claim 1, characterized in that said movable head (17) comprises first attachment means (34) able to be selectively constrained to mating means (49) provided in said support means (19), in order to determine the thrust thereof in a first direction of sliding, and/or the drawing thereof in a second direction of sliding, opposite said first direction, keeping the reciprocal distance constant.

6. Machine as in claim 5, characterized in that said first attachment means comprise an attachment bar (34) pivoted in the lower part of said movable head (17) and able to be attached to a mating attachment block (49) arranged in a mating position on said support means (19).

7. Machine as in claim 5, wherein said movable head (17) and said support means (19) are able to slide on sliding rails (22), characterized in that along said rails (22) there is at least a first release element (18) able to interfere with said first attachment means (34) in order to determine the selective detachment of said movable head

(17) from said support means (19).

8. Machine as in claims 6 and 7, characterized in that said attachment bar (34) comprises, laterally, a rotary element

(52) able to cooperate with said first release elements

(18) so as to determine the detachment from said attachment block (49) and, in proximity with a terminal zone thereof, a shaped surface (53) able to allow the attachment thereof to said attachment block (49).

9. Machine as in any claim from 5 to 8 inclusive, wherein at least two support means (19, 20) are provided, characterized in that a second of said support means (20) comprises second attachment means (50) able to be attached to the first of said support means (19) in order to selectively constrain itself thereto and be thrust in a first direction of sliding, and/or drawn in a second direction of sliding opposite said first direction.

10. Machine as in claims 7 and 9, characterized in that at least a second release element (28) is associated with said rails (22) and is able to interfere with said second attachment means (50) in order to determine the selective detachment of said two support means (19, 20).

11. Machine as in claim 1, characterized in that it comprises a store (21) for said longitudinal bars (12) arranged on one side of the machine (10) and including guide means (46) having at least an inclined segment so as to form a slide for the falling longitudinal bars (12), said inclined segment being arranged between said store (21) and said radial grooves (43, 44; 56, 57) of said rotatable disk (42, 142).

12. Machine as in claim 1, characterized in that it comprises a plurality of arms (23) to support said cage (11) that is progressively formed, said arms (23) being movable between a first high operating position to support said cage (11), and a second lowered retracted position to discharge said cage (11).

13. Machine as in claim 1, characterized in that on said rotary means (25) retaining elements (26) are mounted, each able to retain one end of a respective one of said longitudinal bars (12), and having an adjustable radial position according to the shape and size of said cage (11).

14. Machine as in claim 1, characterized in that said movable head (17) comprises an idle rotor (32) provided with a plurality of guide and positioning eyelets (33) for said longitudinal bars (12).

15. Machine as in claim 1, characterized in that said welding device (31) is of the tracking type.

16. Machine as in claim 7, characterized in that said support means (19) is able to slide longitudinally in idle manner along said rails (22).

17. Machine as in claims 1 and 11, characterized in that each support means (19, 20) comprises a bearing structure

(41) open laterally by means of an aperture (45) and able to connect said guide means (46) to said radial grooves (43, 44; 56, 57).

18. Machine as in claim 17, characterized in that said bearing structure (41) also comprises, in correspondence with said aperture (45), a closing element (47) against the accidental exit of said longitudinal bars (12) from said radial grooves (43, 44; 56, 57).

19. Machine as in claim 1, characterized in that said rotatable disk (42) comprises two series of said radial grooves, respectively a first series (43) and a second series (44), arranged alternated angularly and including different depths correlated to a different radial positioning of said longitudinal bars (12) inside each of them.

20. Machine as in claim 1, characterized in that said rotatable disk (142) comprises two series of said radial grooves, respectively a first series (56) and a second series (57), arranged alternated angularly and including different widths correlated to a different number of said longitudinal bars (12) positioned inside each of them.

21. Machine as in any claim hereinbefore, characterized in that it also comprises retaining means (59) arranged at least in correspondence with a lower part of said rotatable disk (42, 142) and able to prevent said longitudinal bars (12) loaded laterally in said radial grooves (43, 44; 56, 57) from being radially displaced inside the latter, beyond a certain diameter.

22. Method to produce reinforcement cages (11) consisting of a plurality of longitudinal bars (12) and at least a clamping round piece (13) wound around and fixed to said longitudinal bars ( 12 ) , by means of a machine comprising in succession at least a fixed head (16) provided with rotary means (25) with which the ends of said longitudinal bars (12) are associated, a second motorized movable head (17) supporting welding means (31) to weld said clamping round piece (13), and at least a support means (19, 20) able to support the segments of said longitudinal bars (12) on which said clamping round piece (13) has not yet been deposited, characterized in that it comprises at least a loading step wherein said longitudinal bars ( 12 ) are inserted and guided to their correct radial positioning, at least one at a time, from one side of the machine (10) inside respective radial grooves (43, 44; 56, 57) open towards the outside, having a size mating with the transverse section of said longitudinal bars (12) and made on a rotatable disk (42, 142) provided on said support means (19, 20) and arranged substantially coaxial with said rotary means (25), said loading step comprising the sequential rotation of said rotatable disk (42, 142) in order to position said plurality of longitudinal bars (12) inside the relative radial grooves (43, 44; 56, 57) in the desired radial positions provided by the design specifications of said cage (11).

23. Method as in claim 22, characterized in that it comprises a first step of advance of said movable head (17) in a first operating direction, wherein said movable head (17) thrusts said support means (19) keeping a fixed distance therefrom; a second step wherein the constraint between said movable head (17) and said support means (19) is released, in order to allow the two to approach in a position of non-interference with said formed cage (11); and a third step wherein said movable head (17) is retreated in a second operating direction opposite the first, after said cage (11) has been discharged and wherein the constraint is restored in order to automatically reposition also the support means (19) in its start-of- cycle position.

24. Method as in claim 23, wherein at least two support means (19, 20) are provided, characterized in that during the advance of said movable head (17) in the first operating direction, a first of said support means (19) is automatically constrained to a second of said support means (20), and in that during the return travel of said movable head (17) in the second operating direction, the second of said support means (20) is detached automatically from the first of said support means (19) in order to be automatically repositioned in its initial position.