METHOD AND APPARATUS FOR PROCESSING BARS

Abstract

The method for processing bars provides for feeding a predefined number of bars (2) into a feeding station (3). The method further provides for transferring said fed bars to an operating assembly (4) by means of a transfer assembly (5) comprising at least one transfer device (50).

Claims

1. A method for processing bars, comprising the steps of: a. arranging a feeding station capable of receiving said bars on a feeding plane along a longitudinal direction, arranging at least one operating unit for processing said bars on a work surface, arranging an unloading station for receiving said processed bars on an unloading surface, and arranging a transfer device interposed between said feeding station and said unloading station, the transfer device comprising an articulated arm constrained at a height below said work surface, and at least one gripping member articulated to said articulated arm at least around an orientation axis parallel to said longitudinal direction, said gripping member comprising a receiving space for a number of said bars and being movable between an opening configuration wherein said receiving space is open through a respective passage opening through which said number of bars may access said receiving space or can be released out thereof, and a closing configuration wherein said receiving space is closed, to retain said number of bars; b. feeding said bars onto said feeding plane at said feeding station; c. positioning the transfer device at said feeding plane and intercepting said number of bars, by operating said gripping member from said opening configuration to said closing configuration; d. transferring said number of intercepted bars, in a first transfer section, by activating said transfer device in a transfer motion from said feeding plane to said operating unit; e. releasing said number of bars onto said work surface, actuating said gripping member from said closing configuration to said opening configuration; f. operating said operating unit for processing said number of bars; g. collecting by means of said gripping member and transferring said number of processed bars to a second transfer section, by activating said transfer device in said transfer motion from said operating unit to said unloading station; h. releasing said number of processed bars in said unloading station, by operating said gripping member from said closing configuration to said opening configuration; i. between said steps b. and h. operating said transfer device by moving said gripping member in an orientation motion at least around said orientation axis so that said gripping member is oriented with said receiving space overlying said passage opening.

2. A method as in claim 1, wherein said orientation motion includes a tilting motion of said gripping member from one side to an opposite side with respect to the same articulated arm, so that said gripping member may overcome, by crossing it from above, the space represented by said articulated arm, constrained under said work surface.

3. A method as in claim 1, wherein said orientation motion comprises a combination of rotational motions of said articulated arm around said orientation axis and an intermediate pivot axis of said articulated arm, parallel to said orientation axis.

4. A method as in claim 3, wherein said combination of rotational motions further takes place around a constraint axis parallel to said orientation axis, by means of which said articulated arm is constrained to said portion below said work surface.

5. A method as in claim 1, wherein said step h. of releasing said number of processed bars involves disengaging said number of processed bars with at least partially lifting motion from said unloading surface, thus allowing an orderly support or overlapping of the same in the unloading station.

6. A method as in claim 1, wherein said operating unit comprises a bending and/or curving unit.

7. An apparatus for processing bars, comprising a feeding station capable of receiving said bars on a feeding plane along a longitudinal direction, at least one operating unit for processing said bars on a work surface, an unloading station, to receive on an unloading surface said processed bars, and a transfer device interposed between said feeding station and said unloading station, the transfer device comprising an articulated arm constrained at a level below said work surface and at least one gripping member articulated to said articulated arm at least around an orientation axis parallel to said longitudinal direction, said gripping member comprising a receiving space for a number of said bars and being movable between an opening configuration in which said receiving space is open through a respective passage opening through which said number of bars can access said receiving space or can be released out thereof, and a closing configuration in which said receiving space is closed to retain said number of bars, said transfer device being operable in a transfer motion to bring said gripping member in a first transfer section between said feeding station and said operating unit and in a second transfer section between said operating unit and said unloading station, to release said number of said bars respectively on said work surface and on said unloading surface, said transfer device being operable to move said gripping member in an orientation motion at least around said orientation axis, so as to orient said gripping member with said receiving space overlying said passage opening.

8. An apparatus as in claim 7, wherein said gripping member is operable in said orientation motion by overturning the same member from one side to an opposite side with respect to said same articulated arm, so as to be above said passage opening.

9. An apparatus as in claim 7, wherein said articulated arm comprises a first member and a second member mutually articulated at least around an intermediate axis parallel to said axis of orientation, wherein said second member is articulated to said gripping member at least around said orientation axis, said transfer device being operable according to a combination of rotational motions around said orientation axis and said intermediate axis, to achieve said orientation movement of said gripping member.

10. An apparatus as in claim 9, wherein said articulated arm is articulated at said height below said work surface at least around a constraint axis parallel to said orientation axis, said transfer device being operable, according to said combination of rotational motions, further around said constraint axis, to achieve said orientation motion of said gripping member.

11. An apparatus as in claim 7, wherein said transfer device is constrained in an internal position to the base of said operating unit, said work surface comprising a notch for enabling said transfer device to emerge from said work surface following said orientation motion.

12. An apparatus as in claim 11, wherein said articulated arm comprises a spacer extending between said first member and said second member and/or between said second member and said gripping member, to bring said gripping member close to an opposite internal side of said operating unit, so as to operate in correspondence with said area.

13. An apparatus as in claim 11, wherein said first member of said articulated arm is shaped like a double elbow.

14. An apparatus as in claim 7, wherein said transfer device is integrated with said operating unit.

15. An apparatus as in claim 7, wherein said transfer motion is transverse to said longitudinal direction.

16. An apparatus as in claim 7, further comprising a further operating unit, which is movable with respect to said operating unit along said longitudinal direction.

17. An apparatus as in claim 7, wherein said operating unit is a bending and/or curving unit, comprising a bending and/or curving head equipped with bending members operating on said work surface, between which an insertion seat is defined for said bars to be bent and/or curved.

18. An apparatus as in claim 7, wherein said gripping member is operable from said oriented configuration, wherein the gripping member is arranged above said work surface or said unloading surface @H, so as to disengage said number of said bars with at least partially lifting motion from said work surface or from said unloading surface respectively.

19. An apparatus as in claim 7, further comprising at least one further said transfer device configured to cooperate with said transfer device along said longitudinal direction.

20. An apparatus as in claim 7, wherein said gripping member comprises a pair of jaws, at least one of which being movable relative to the other between said opening configuration and said closing configuration, at least one of the jaws internally comprising a recess and a protruding end portion, in said closing configuration one said bar being clamped by said protruding portion and the remaining bars being received by said recess.

21. An apparatus as in claim 7, wherein said articulated arm of said transfer device has said gripping member and a further gripping member.

22. An apparatus as in claim 7, further comprising at least another transfer device to provide a plurality of said transfer devices which are movable along said longitudinal direction, so as to exploit the entire longitudinal extension of said unloading station, for unloading said processed bars in a corresponding longitudinal succession.

23. An apparatus as in claim 7, further comprising, at one side of said feeding plane, at least one additional receiving plane dedicated to receiving bars cut to size coming from a further source.

Description

DESCRIPTION OF DRAWINGS

[0059] The details of the invention will become more evident from the detailed description of a preferred embodiment of the apparatus for processing, in particular bending, bars which implements the method according to the invention, shown by way of example in the accompanying drawings, wherein:

[0060] FIGS. 1 and 2 respectively show a perspective view of the apparatus according to different embodiments of an unloading station;

[0061] FIG. 3 shows an enlarged side view of a detail of the apparatus in an operating step;

[0062] FIGS. 4a and 4b respectively show a perspective view of a detail of the invention in subsequent operating steps of the apparatus according to the invention;

[0063] FIG. 5 shows a perspective view of a portion of the apparatus in the same operating step shown in FIGS. 4a and 4b, in a different embodiment of the feeding station of the apparatus according to the invention;

[0064] FIG. 6 shows a perspective view of a detail of the invention in a further operating step;

[0065] FIG. 7 shows an enlarged side view of a detail of the apparatus according to the invention;

[0066] FIGS. 8a, 8b, 8c respectively show a side view of the apparatus according to the invention in subsequent operating steps of transferring the bars;

[0067] FIG. 8d shows a side view from a side opposite to that of FIGS. 8a-8c, of the apparatus according to the invention, in the operating step shown in FIG. 8c;

[0068] FIGS. 9a, 9b, 9c, 9d, 9e, 9f, 9g show a perspective view of the apparatus according to the invention in successive operating steps, for manufacturing rebars with clockwise and counterclockwise bends on the same bar;

[0069] FIGS. 10a, 10b, 10c respectively show a plan view of the apparatus according to the invention, in successive steps of manufacturing a bar with clockwise and counterclockwise bends, according to a method alternative to that shown in FIGS. 9a-9g;

[0070] FIGS. 10d and 10e respectively show a perspective view of the same apparatus in steps 10a and 10b;

[0071] FIGS. 11a, 11b, 11c respectively show a plan view of the apparatus in successive steps of manufacturing a bar with bends of different radius of curvature at the respective ends;

[0072] FIGS. 12a, 12b respectively show a plan view of the same apparatus in successive operating steps of manufacturing a bar with bends of different radius of curvature at the ends, according to an operating mode different than that shown in FIGS. 11a-11c;

[0073] FIGS. 13a, 13b, 13c, 13d, 13e, 13f show a perspective view of a portion of the apparatus in successive operating steps of manufacturing a bar with three-dimensional bends;

[0074] FIGS. 14a, 14b, 14c, 14d show a plan view of the apparatus in successive steps of manufacturing a so-called truss-bar;

[0075] FIG. 15a shows a perspective view of the transfer assembly of the apparatus according to a different embodiment;

[0076] FIGS. 15b and 15c respectively show a perspective view and an enlarged view of a detail of the same transfer assembly, in an operating step of taking up the bars;

[0077] FIG. 15d shows a perspective view of the transfer assembly in a step of inserting the bars in a bending head of the apparatus;

[0078] FIG. 15e shows a perspective view of the transfer assembly shown in FIGS. 15a-15e in an operating step of unloading the bars;

[0079] FIG. 16 shows a perspective view of the apparatus according to a further embodiment;

[0080] FIGS. 17a, 17b and 17c respectively show an enlarged partial view, a complete view and an enlarged partial view in perspective of the apparatus according to the embodiment shown in FIG. 16, in subsequent operating steps of handling the bars.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0081] With particular reference to these figures, the numeral 1 indicates as a whole the apparatus for processing, in particular for bending, bars 2, in particular iron rods for reinforced concrete.

[0082] The apparatus 1 comprises a feeding station 3, at which the bars 2 intended to be bent arrive, an operating assembly comprising at least one operating unit, preferably a pair of operating units, and a transfer assembly 5 for transferring the bars 2 between various stations, as specified below, and an unloading station 6, in particular on an unloading plane (see in particular FIG. 1).

[0083] In particular, the transfer assembly 5 is preferably arranged in an intermediate position between the feeding station 3 and the unloading station 6.

[0084] The operating assembly preferably indicates a bending unit 4 and/or curving unit, the operating units therefore being the bending unit and/or curving units 41.

[0085] The apparatus described below comprises a pair of bending units 41 and/or curving units for making, in particular, shaped and/or curved products at one or both ends, but according to the invention, apparatuses can be provided in which it is present a single bending and/or curving unit 41.

[0086] In the following the term bending unit will be used to indicate indifferently bending and/or curving unit.

[0087] In particular, the bending units 41 are aligned and can be activated independently, in a known way, both or one of them, along a longitudinal direction to the side of the feeding station 3.

[0088] The feeding station 3 defines a feeding plane 3a, adapted to receive the bars 2, possibly cut to size, arranged according to the aforementioned longitudinal direction alongside the bending unit 4 (see FIG. 2). The feeding plane 3a can be substantially horizontal, for example.

[0089] The bars 2 can reach the feeding station 3 by means of an axial transport, for example by means of a roller conveyor, a transversal transport, for example by overturning means, or by air, for example by a bridge crane.

[0090] The feeding station 3 preferably comprises at least one transversal positioning device 31, for example of the catenary type, to allow the fed bars 2 to be moved transversely.

[0091] Preferably the feeding station 3 comprises a plurality of transversal positioning devices 31, arranged in succession, for example uniformly distributed, along the longitudinal direction, in order to allow an optimal displacement for bars 2 of any length.

[0092] Each transversal positioning device 31 can be preliminarily operated in an ordering, preferably alternating, motion, and in a transverse direction, so as to favor a distribution of the bars 2 on the feeding plane 3a in an ordered, untangled and leveled configuration, i.e. arranged on a single layer.

[0093] More precisely, the feeding station 3 has a longitudinal extension substantially equal to the maximum length of the bars 2 to be processed, so as to support bundles of bars 2 or single bars 2 of maximum length, arranged on the feeding plane 3a according to a substantially longitudinal orientation.

[0094] The feeding station 3 also comprises end-facing means 32 to ensure the correct alignment of the ends of all the bars 2 fed. The alignment means 32 preferably form a flat abutment wall arranged at the end of the feeding plane 3a and preferably movable with an alternative alignment motion along the longitudinal direction so as to perform a hammering action on one or more bars at the same time (see FIGS. 4a and 4b).

[0095] According to a particular embodiment of the feeding station 3, illustrated in FIG. 5, it is possible to provide, at the side of the feeding surface 3a, at least one additional receiving surface 3a dedicated to receiving cut-to-size bars coming from a further source, for example from a straightener. This additional receiving surface 3a can be associated with additional squaring means 33, arranged at the end of the same, to ensure the correct alignment of the bars 2 positioned thereon and intended to be bent by the bending unit 4. Said alignment means can be similar to the squaring means 32 or for example form a fixed abutment wall. In this case an alignment motion in the longitudinal direction, against the above mentioned wall, can be made in cooperation with the transfer assembly 5, to bring the bars 2 to abut said wall.

[0096] The bending units 41 are arranged at the side of the feeding station 3 and each carry, in a known way, a bending head 40.

[0097] Each bending unit 41 operates on a work surface , on which the bars 2 can be placed and bent by bending members.

[0098] Each bending head 40 can be of any type. For example, the bending head 40 can provide a bending tool consisting of a central bending spindle 42 associated with an eccentric bending pin 43 (see FIGS. 8a to 8d), in addition to an abutment 44 suitable for locking in suitable way the piece being processed (see FIGS. 9a to 9g).

[0099] Alternatively, for example, the bending head 40 can carry a double spindle 45 crossed by a seat for the bars 2 and the same eccentric bending pin 43, movable around the double spindle 45 for bending the interposed material, in addition to the abutment 44 suitable for blocking the piece being processed in a suitable way (see FIGS. 13a to 13f).

[0100] The abutment 44 is preferably also provided in the case in which the bending head 40 comprises the central spindle 42 and the eccentric bending pin 43.

[0101] In any case, between the bending members, central spindle 42 and eccentric pin 43 or between double spindle 45 and eccentric pin 43, an insertion seat 46 is defined for the bars 2, at which, when the bars 2 are correctly housed therein, the eccentric pin 43 acts in cooperation with the respective bending member, causing the desired bending of a respective portion of the bars 2 (see in particular FIG. 8b).

[0102] In practice, the eccentric pin 43 is configured to bend a number of bars 2 which is inserted inside the insertion seat 46, rotating around the central spindle 42 or the double spindle 45, being movable in a part of the work surface , opposed to abutment 44.

[0103] The abutment 44 is in turn configured to retain respective portions of the aforementioned number of bars 2 in the step of bending carried out by the eccentric pin 43. These portions are not intended to be engaged in the same bending step by the eccentric pin 43.

[0104] The bending units 41 are movable with a relative translation motion along the longitudinal direction to position the bars 2 between them. More precisely, at least one bending unit 41 is movable with the aforementioned translation motion along respective guide rails 47 (see FIG. 1), in such a way as to adapt the position along the longitudinal axis, as a function of the length of the bar 2 to be processed and the geometry to be obtained.

[0105] More precisely, the apparatus according to the invention permits to bend a plurality of bars 2 at each bending cycle, but it can also be used to bend one bar 2 at a time.

[0106] The transfer assembly 5 comprises at least one transfer device 50 preferably mounted integral, therefore integrated, with a respective bending unit 41. For example, the transfer device 50 can be constrained, in particular pivoted, on the internal side or, as described below, on the external side, with respect to the longitudinal direction and to an opposite bending unit 41.

[0107] The internal side is intended as the side of the bending unit 41 in which the abutment 44 is fixed, while the external side is the opposite side, in which the eccentric pin 43 operates, to bend the number of bars 2 inserted in the insertion seat 46.

[0108] Preferably, the transfer unit 5 comprises a transfer device 50 serving each bending unit 41 (see FIG. 8b).

[0109] Advantageously, the apparatus 1 can comprise at least one further transfer device 50, dissociated from the bending units 41, for example intermediate, fixed or movable independently between the bending units 41 themselves, otherwise quite similar to each transfer device 50 (see FIG. 13a). The transfer devices 50, 50 can therefore be operative in cooperation along the whole longitudinal extension of the apparatus 1, thus allowing, in particular, the manipulation, the transfer and the unloading in sequence, on the unloading plane at the unloading station 6, of shaped bars 2a of shorter length than the total length of the apparatus 1 (see FIG. 2).

[0110] Each transfer device 50, 50 preferably comprises an articulated arm 51 and at least one gripping member 52 carried to the opposite end of the articulated arm 51.

[0111] The articulated arm 51 is mounted below the work surface , preferably articulated, in particular articulated or pivoted, at the base of the bending unit 41 below the work surface .

[0112] More precisely, the articulated arm 51 preferably comprises at least a first member 51a and a second member 51b, mutually articulated at an intermediate articulation axis 53 (see FIG. 8b). The arm 51, preferably by means of the same first member 51a, is also articulated below the work plane of the bending unit 41 at a constraint axis 54 (see FIG. 8d). Alternatively, the articulated arm 51 may comprise a greater number of articulated members, also provided with different, in particular further, degrees of freedom.

[0113] The articulated arm 51 is in turn articulated to the gripping member 52 at an orientation axis 55, in particular at the extremity (see FIG. 8d).

[0114] In particular, the intermediate axis 53, the constraint axis 54 and the orientation axis 55 are preferably parallel to the aforementioned longitudinal direction.

[0115] The transfer device 50 is movable, in particular oscillating, in a transfer motion, between a feeding position 3b at the feeding station 3 and an operative bending position, in particular for inserting the bars 2 into the insertion seat 46 of the bending head 40. In particular, at the feeding position 3b the bars 2 are arranged and aligned in a single layer (see FIG. 6).

[0116] The transfer device 50, 50 can be movably operated in the aforementioned transfer motion by means of a respective motor assembly.

[0117] Furthermore, the transfer device 50, 50 can be further moved by an unloading, preferably oscillating, motion between the aforementioned bending operating position and an unloading position in the unloading station 6, arranged to the side of the bending unit 4, opposite to the feeding station 3.

[0118] In practice, the transfer assembly 5, comprising at least one transfer device 50, preferably a pair of transfer devices 50 and possibly the further transfer device 50, is configured to transfer the number of bars 2 preferably between three stations, wherein the aforementioned transfer devices can be operated in a coordinated manner.

[0119] More precisely, the transfer assembly 5 preferably permits to transfer the number of bars 2 to be processed from the feeding station 3 to the bending unit 4, so that at least one bending step takes place there, as well as to transfer the number of bent bars 2a from the bending unit 4 to the unloading station 6.

[0120] The transfer assembly 5 then preferably allows a first transfer and a second transfer to be carried out, in an overall path between, respectively feeding 3 and unloading 6 stations, opposite each other with respect to the bending unit 4, arranged in an intermediate position between them. The bending unit 4, therefore, can be a crossing station in this sense.

[0121] In order to allow this crossing, the transfer assembly 5, which is preferably placed at the intermediate bending unit 4, advantageously permits to take up the number of bars 2 according to any orientation and to release the same number of bars 2 on a respective releasing, operating or unloading plane, in an ordered configuration, in particular in abutment and, in the case of a plurality of bars 2 or bent bars 2a, stacked, i.e. superimposed, one on the other. In particular, according to the described path, the number of bars 2 can be either released, for subsequent bending, or taken up at the insertion seat 46. To obtain this effect, the gripping member 52, of each transfer device 50, 50 involved, is oriented following an orientation motion, in particular with an overturning, indifferently in the first or second mentioned transfer, empty o when holding the number of bars 2, to release the bars 2.

[0122] In particular, the gripping member 52 may be overturned, following the aforementioned orientation motion, first on one side and then on the opposite side with respect to the articulated arm 51 to which it is articulated, as described in detail below.

[0123] Among the consequences of this circumstance, in particular, the number of bars 2, 2a can for example cross the bending unit 4 and be released with an open motion of the gripping member 52.

[0124] Furthermore, the gripping member 52 can be oriented, following the aforementioned overturning, with a respective passage opening 7 facing downwards in use, in particular towards the releasing plane. In other words, thanks to the aforementioned overturning, the gripping member 52 can be overhanging, in the overturned configuration, with respect to the passage opening 7.

[0125] This circumstance permits, for example, to accompany the number of bars 2, 2a on the unloading plane into the unloading station 6, in abutment thereon, and to separate from this same unloading plane , with a lifting motion of the gripping member 52.

[0126] More precisely, the articulated arm 51 is preferably shaped so as to overturn the gripping member 52, by means of corresponding rotations around the aforementioned joints, for example around the intermediate axis 53 and the orientation axis 55. Consequently, for example, a number of bars 2 may be taken up from the feeding position 3b, (see FIG. 6) and transferred to the bending position (see FIGS. 8a, 8b and 8c), crossing the articulated arm 51.

[0127] Thanks to the aforementioned overturning, in particular, the transfer device 50 is able to release the number of bars 2 from above, inserting them into the insertion seat 46.

[0128] The articulated arm 51 is also preferably capable of taking up and transferring the bars 2 in the aforementioned path, between the bending position and the unloading position, in particular without making any shifting of the number of bars 2 engaged, avoiding unwanted misalignments, especially if the bars are already bent. The articulated arm 51, in particular, carries the gripping member 52 in a first configuration at the feeding position 3b, while it can bear the gripping member 52 overturned in the bending position. It is possible to provide such overturning, alternatively, in the second transfer, between the bending position and the unloading station 6.

[0129] In particular, the kinematics of the articulated arm 51 is preferably configured in such a way that the member articulated to the gripping member 52 can oscillate above the bending head 40, in particular, with a roto-translation motion (see in particular the FIGS. 8a-8d). Thanks to the particular conformation of the articulated arm 51, the transfer device 50, 50 can therefore transfer the bars 2, so that they can overcome, by crossing it from above, the encumbrance of the articulated arm 51, constrained under the work surface .

[0130] Likewise, the transfer device 50 can unload the bent bars 2a, without altering their orientation and ordered arrangement. In fact, thanks to the particular kinematics of the articulated arm 51 which carries the gripping member 52, the bent bars 2a are accompanied to the unloading station 6 and released from above, bringing the gripping member 52 into an open configuration. This circumstance makes it possible, in particular, to orderly sort into piles, that is to orderly superimpose the bent bars 2a.

[0131] Release from above means that the passage opening 7 of the gripping member 52 is facing downwards in the release condition.

[0132] Furthermore, it should be pointed out that the particular kinematics of the articulated arm 51 allows the transfer device 50 to cooperate with the bending units 41 in the steps of bending the bars 2, orienting and rotating in a suitable way the number of bars 2, 2a retained, as described in detail below.

[0133] The kinematic configuration of the solution described for the transfer device 50, 50 is to be considered as preferred, but not limiting. In particular, it is possible to provide that the articulated arm 51 includes a different number of members and that the constraints between them can be different, thus giving rise to different relative motions, rotational and/or translational, according to axes oriented in a different way.

[0134] The gripping member 52 is preferably of the jaw type (see for example FIG. 6).

[0135] It preferably comprises a pair of jaws 52a of which at least one is movable relative to the other in a closing and opening motion, between an open configuration and a closed configuration. More precisely, in the open configuration, the jaws 52a are set apart from each other to release the bars 2, 2a or to insert them, through the passage opening 7, while in the closed configuration the jaws 52a are mutually approached, to enclose and intercept a number of bars 2, 2a (see FIG. 7).

[0136] In particular, the jaws 52a are shaped so as to define between them a receiving space 56, which in the closed configuration is closed, permitting to retain, in particular clench, the aforementioned number of bars 2, 2a, while in the open configuration is open through the passage opening 7.

[0137] In particular, at least one jaw 52a can shape internally a respective recess 57 and an inwardly projecting end portion 58.

[0138] The recess 57, in particular, can have at least partially a flat wall, intended to face parallel to a respective flat wall of the opposite recess 57, so that the bars 2, 2a retained in the receiving space 56 in the closed configuration are arranged side by side on the same floor.

[0139] A layer 59 of elastic material, for example rubber, may be applied on the flat wall of at least one recess 57 to maintain the positioning of the bars 2, 2a during the overturning and transfer of the bars 2, 2a as described in detail below.

[0140] Furthermore, the at least one protrusion 58 can cooperate with the at least one recess 57 to hold the intercepted bars 2. Advantageously, however, the at least one protrusion 58 is configured to preferably clamp only the end bar 2, 2a, between the intercepted ones, while the remaining bars 2, 2a are held in an orderly manner inside the receiving space 56 (see FIG. 7).

[0141] The unloading station 6 can be defined in the space, in particular on the ground, next to the bending unit 4, to receive the bent bars 2a, already subjected to a bending cycle by the at least one bending unit 41 (see FIG. 1).

[0142] The space on the ground may be further equipped with containment devices 60, preferably movable, for example made of racks, conveyor belts, trolleys or catenary means, to allow the unloading station 6 to be easily freed (see for example FIG. 2).

[0143] The operation of the apparatus according to the invention is understandable from the above description.

[0144] Single bars or, preferably, bundles of bars 2 to be bent are fed into the feeding station 3 on the feeding plane 3a.

[0145] The transversal positioning devices 31, with a series of alternating movements, move the bundle of bars 2 fed on the feeding plane 3a. Finally, the bars 2 are arranged in an orderly alignment in a single layer on the feed plane 3a.

[0146] The gripping member 52, preferably of at least one pair of transfer devices 50, 50, is then moved closer to a predefined transverse distance to the feeding station 3 and brought into the open configuration, so as to intercept a predetermined number of bars 2. This predefined transverse distance substantially corresponds to the transverse dimension of the number of bars 2 to be taken up. In particular, if the bars 2 are placed side by side due to the action previously performed by the transversal positioning devices 31, the number of intercepted bars 2 is perfectly equal to that expected (see FIG. 3).

[0147] The gripping member 52 is then operated in the closed configuration to clench the number of bars 2 to be subjected to the bending cycle.

[0148] Subsequently, the transfer devices 50, 50 are operated in a coordinated manner in the transfer motion from the feeding position 3b to the bending position, while moving the gripping device in the orientation motion. Preferably the gripping member 52 is overturned at the same time and, consequently, the bars 2 are correctly intercepted. The orientation motion, in particular of overturning, of the gripping member 52 can be carried out, alternatively, in the subsequent transfer, from the bending position to the unloading station 6 or empty, in the absence of retained bars 2.

[0149] The at least one bending unit 41 then performs a bending cycle, advantageously with the cooperation of the transfer devices 50, 50 to obtain bent bars 2a.

[0150] For example, the bending unit 41 can make a succession of bends in alternately opposite directions, simply thanks to the intervention of the transfer assembly 5. In particular, after the execution of a first bend (see FIGS. 9a and 9b) the transfer assembly 5 can take up the bent bars, lift them from the insertion seat 46 (see FIGS. 9c and 9d), wait for the bending head 40 to reverse the position of the bending pin 43 (see FIG. 9e) and reinsert the bars, from the side opposite to the central spindle 42, in the insertion seat 46 suitably positioned (see FIG. 9f), to carry out a bending in the opposite direction to the previous one (see FIG. 9g), around the spindle 42.

[0151] Alternatively, if the bar 2 to be bent is only one, the at least one bending unit 41 can carry out a cycle of bending in succession in alternately opposite directions, at the ends of the bars 2, cooperating in a different way with the transfer assembly 5. In particular, after carrying out a first bend (see FIGS. 10a and 10d) and positioning relative to the bending unit 41 in the longitudinal direction (see FIG. 10b), the transfer assembly 5 can clamp respective portions of the bars 2 being processed, by rotating them by an appropriate angle, in particular by 180, so as to correspondingly overturn the respective end portions (see FIGS. 10b and 10e). At this point, the bending head 40 can perform the subsequent bending in the opposite direction to the previous one (see FIG. 10c).

[0152] Furthermore, a pair of bending units 41 can perform bends having different radius of curvature on the opposite ends of the bars.

[0153] According to a first operating mode, it is possible to provide for installing respective differentiated bending heads 40 on the bending units 41, in particular differentiated spindles 42 (see FIG. 11a). The bending is then performed on one end of the bars 2, by operating the respective bending head 40 and possibly holding the bars by means of the gripping member 52 of the transfer devices 50 (see FIG. 11b). Thanks to the same devices 50, the bars 2 are then disconnected from the bending unit 40 just used, suitably positioned along the transverse direction, and finally inserted at the insertion seat of the opposite bending unit 40 (see FIG. 11c).

[0154] Alternatively, it is possible to achieve the same result, by making the end bends with differentiated radius of curvature, holding the bars 2 by means of the gripping members 52, so that they are positioned tangent to both spindles 42 (see FIG. 12a). In this circumstance, the bars 2 will be inclined, on the work plane , with respect to the longitudinal direction. At this point, in a single step, it is possible to carry out the bending of the ends of the bars 2 (see FIG. 12b).

[0155] Furthermore, it is possible to make three-dimensional pieces, for example by using a bending head 40 equipped with shapes 45. This result is achieved by making a first bend (see FIG. 13a), then rotating, thanks to the gripping member 52 and the particular articulation to the articulated arm 51, the bars 2 themselves around the respective longitudinal axis, by an appropriate angle (see FIG. 13b), and then perform a subsequent bend (see FIGS. 13c-13f).

[0156] Finally, it is possible to easily produce bent bars 2a so-called truss-bars, thanks to the cooperation of the transfer assembly 5 and to the provision of suitable opposing members to the eccentric bending pin 43 positioned on the work surface (see FIGS. 14a 14d).

[0157] The transfer unit 5 is finally activated in the unloading motion to transfer in an orderly manner the bent bars 2a from the bending position to the unloading position in the unloading station 6.

[0158] According to a further embodiment shown in FIGS. 15a-15e it is possible to provide that the transfer device 50 is constrained under the work surface , externally to the bending head 40 of the bending unit 41. The external side is intended as the side of the bending head 40 opposed to that in which the number of bars 2 is held during the bending step, for example by means of the abutment 44. In other words, the external side is the side in which, with respect to the spindle 42 or the double spindle 45, the eccentric pin 43 of the bending head 40 operates.

[0159] The transfer device 50 is preferably integrated with the bending unit 41 and, in particular, internally constrained to the base thereof.

[0160] In particular, the articulated arm 51 can be advantageously constrained, in particular pivoted, to the base of the bending unit 41, inside a recess 41a that extends through the base to the work surface . The recess 41a, in particular, can allow the oscillation of the first member 51a in the different handling steps described above.

[0161] This embodiment, for the rest quite similar to that described above, frees up the space on the inner side and, in the case of a pair of bending units 41, between the bending units 41, thus allowing to reduce the minimum distance at which the bending units 41 themselves can be positioned. In this way the apparatus 1 is able to produce very short rebar pieces.

[0162] To allow the operations of taking up, inserting and unloading the bars 2, 2a, the articulated arm 51 of the transfer device 50 can in this case comprise at least one spacer member 51c, for example interposed between the first member 51a and the second member 51b. In particular, the spacer member 51c can extend in this case along the intermediate axis 53, to bring the gripping member 51 closer to the inner side of the bending unit 41, so as to operate at this area, to handle the bars 2, 2a (see for example FIGS. 15a and 15c). Alternatively, the spacer 51c can be interposed between the second member 51b and the gripping device 52, extending for example along the orientation axis 55. According to a further variant, different spacers can be interposed, extending respectively along the intermediate axis 53 and along the orientation axis 55, respectively.

[0163] Finally, the first member 51a can be shaped so as to avoid interfering in particular with the work surface during the transferring and/or unloading steps of the bars 2 or of the bent bars 2a. For this purpose, for example, the first member 51a can advantageously extend with a double crank conformation, for example C-like (see FIG. 15e).

[0164] According to a third embodiment shown in FIGS. 16, 17a, 17b and 17c it is possible to provide that the transfer device 500 is constrained under the work plane by means of a respective kinematic torque, but which, unlike the forms of embodiment described above, is split, thus bearing a pair of gripping members.

[0165] More precisely, the transfer device 500 comprises in addition to the gripping member 52, operating for example from the internal side of the bending head 40, a further gripping member 520, operating from the opposite side with respect to the same bending head 40.

[0166] In practice, starting from the common first member 51a, the spacers 51c and 510c are developed, starting from the intermediate axis 53, respectively from opposite sides to each carry the second member 51b and 510b respectively. Each of the latter is in turn articulated to the gripping member 52, 520 (see FIG. 17a).

[0167] This embodiment, which is for the rest quite similar to that described above, permits to support each number of bars to be processed even with a single transfer device. As illustrated in FIG. 16, it is in fact possible to avoid the use, preferably, of an additional transfer device 50 which is interposed between the bending units 41. Moreover, advantageously, the branches from the common first member 51a can be moved independently in order to handle the bars 2 optimally. In particular, for example, in the processing step, the number of bars 2 can be held only by the gripping member 52, while the further gripping member 520 is in a remote position, in which it does not interfere with the bending operations (see FIG. 17c).

[0168] The apparatus for bending metal section bars in bars according to the invention therefore achieves the purpose of allowing the optimal processing, for example bending, of bars, in particular by reducing the space occupied to the maximum and optimizing production's efficiency.

[0169] In the practical embodiment of the invention, the used materials, as well as the shape and the dimensions, may be modified depending on needs.

[0170] Should the technical features mentioned in any claim be followed by reference signs, such reference signs were included strictly with the aim of enhancing the understanding of the claims and hence they shall not be deemed restrictive in any manner whatsoever on the scope of each element identified for exemplifying purposes by such reference signs.