Description

Machine used to assemble metal cages for reinforced concrete piles or similar items.

The present invention relates to a machine used to assemble steel cages or similar items used to obtain reinforced concrete, in particular for reinforced concrete piles.

Reinforced concrete piles have a steel core formed of a reinforcement made of steel, steel iron or similar materials, according to the specific needs, which is drowned into concrete.

Piles generally have a round or polygonal transversal section; the internal reinforcement normally follows the shape of the said section with a series of steel reinforcement rods or longitudinal metal bars transversally joined by brackets, that is to say by one or more rods that are externally wound, normally with spiral direction, around the longitudinal rods and fixed to them by means of welding or tying.

The reinforcement is formed of a series of rods or metal bars normally arranged according to the shape of the reinforced concrete pile it is used for: for example, longitudinal rods are arranged in a cylindrical shape for cylindrical piles, or in a cylindroid shape with square base for square piles, etc.

Longitudinal rods are defined as "cross pieces" while the rods forming the helix are generically defined as "spiral". According to a semi-automatic production method of the known art, the reinforcement is produced as follows: the cross-pieces are fixed manually on a machine with housings in the desired positions, for example according to a circular pattern in the case of cylindrical piles; then, the operator fixes the spiral in the initial point manually by means of bending, welding or tieing. Due to the rigidity and weight of the rods, the manual fixing of the initial point is a very dangerous operation for the worker.

In general terms, the machine moves the cross pieces forward and rotates

them with respect to the point where the rod forming the spiral is fed, which is a fixed point with respect to the machine frame.

The spiral is forrped on the cross pieces according to a defined pitch and the crossing points between spiral and cross pieces are automatically welded by the machine.

According to the machine configuration, a welding torch is fixed onto a floating support that follows the spiral, through two rollers that rotate on the rod of the spiral as soon as it is deposited, embracing the spiral; moreover, a mechanic lever mechanism actuates the welding torch when the spiral wire passes in the proximity of one of the rotating cross pieces.

However, the position tolerances of the mechanical lever mechanism often originate defective welding.

Moreover, since the rollers are specified for the diameter of the reinforcement rods, if machining operations have to be carried out on rods with different dimensions, before starting the following operation, the machine has to be set up with the specific type of reinforcement rods that will be used, with consequent down-time and high costs.

Additionally, it is impossible to use cross pieces with null distance, that is to say cross pieces with double or triple rods or with more than one rod; in fact, the mechanical lever mechanism that actuates the welding head upon the passage of a reinforcement rod would only detect the passage of the first of the two or more reinforcement rods in parallel position, without welding the second or the third of the rods. The final point of the spiral winding is welded by the operator manually, with the aforementioned risks.

The often defective welding is checked by the operator visually, who repairs the points where welding has failed or ties the points with unsatisfactory welding, thus forcing the operator to work again in not perfectly safe conditions. Reinforcements must be sometimes provided, being composed of rings situated along the longitudinal direction of the cage. The rings are made of one or more turns of the reinforcement rods, which

are however situated in internal position in the structure of the cage according to the known art.

This occurs because the machines according to the known art do not have the possibility to change the helix pitch and, most of all, because they do not have the possibility to have the spiral helix pitch equal to the diameter of the reinforcement rod that forms the spiral.

Due to the configuration of the welding device, the rollers that are used to follow the spiral do not allow the reinforcement rod of the helix to get close enough to have a null distance between two consecutive turns of the spiral, that is to say a pitch equal to the diameter of the reinforcement rod that forms the spiral.

Therefore the rings are prepared separately and inserted manually by the operator inside the reinforcement that is being produced: the spiral winding and welding cycle is interrupted, the operator inserts the reinforcement ring or rings inside the cross pieces and fixes the ring to the cross pieces by means of manual welding.

Not only is this operation uncomfortable, because the operator must insert the ring between cross pieces that are already fixed in position, with high risk due to the movement of the same cross pieces, but is also slows the production process down, because it forces the operator to stop the production cycle to insert and fix the ring or rings in internal position. The purpose of the present invention is to devise a machine used to assemble steel cages or similar items used to obtain reinforced concrete, in particular for reinforced concrete piles, which is able to solve the drawbacks of the known art.

The purpose of the present invention is a machine used to assemble steel cages for reinforced concrete piles or similar items, the said cages being composed of at least multiple cross pieces around which a spiral reinforcement rod is wound, the said machine comprising at least: two housing heads for the cross pieces, a deposition device of at least one spiral rod, a welding torch to weld the cross pieces and the spiral rod, the said machine also comprising a control system for the welding torch and at least

one vision device situated in the welding torch to detect images of the welding area, designed to detect the passage of each crossing point between a cross piece aηd the spiral rod in the welding area, the said control system being designed to receive the images of the welding area transmitted by the vision system, and switch on the welding torch in the crossing point.

This allows to completely or practically completely eliminate the manual passages of the machines according to the known art, overcoming the aforementioned drawbacks: the vision system, such as a video camera, films the welding area and sends the images to the control system. When the control system identifies the passage of a point where the cross piece meets with the spiral rod in the welding torch, it actuates the welding torch, thus welding the two components.

Moreover, another advantage consists in the fact that the mechanical lever mechanisms and rollers of the machine according to the known art are eliminated, providing more exact welding and, most importantly, having a spiral pitch equal to the rod diameter.

This allows to generate reinforcement rings external to the cage of cross pieces, thus avoiding the insertion of the reinforcement rings inside the cage according to the known art, saving on time and manufacturing costs and reducing risks for the operator.

The winding initial and final point of the spiral rod can be automatically welded, avoiding risks for the operator and speeding up the manufacturing process.

The machine down time is advantageously reduced because it is no longer necessary to set up the machine for different rod diameters and, moreover, the reinforcement rings can be made with the same rod used for the spiral. The present invention also relates to cages for reinforced concrete piles or pillars or similar items, in which the cage comprises at least three or more cross pieces wound by a spiral rod, and provided with reinforcement rings, in which the said reinforcement rings are obtained in external position to the cross pieces with the same rod used for the spiral. The present invention will be cleared with reference to the enclosed

drawings, wherein: fig. 1 illustrates a generic machine of known type used to assemble cages for reinforced concrete piles; fig. 2 illustrates the machine according to the present invention during the initial work phase; fig. 3 illustrates the machine of fig. 2 during a more advanced work phase compared to fig. 2; fig. 4 is a view of a detail of the device according to the present invention. fig. 5 illustrates a cage for reinforcement concrete piles according to the present invention; fig. 6 illustrates another cage for reinforcement concrete piles according to the present invention.

Figs. 7 and 8 illustrate a constructive detail of the machine of the invention according to a specific embodiment. Fig. 1 illustrates a generic machine (1 ) of known type used to assemble cages (2) for reinforced concrete piles.

The cages (2) are obtained by means of multiple cross pieces (3) wound by a spiral rod (4); in the case illustrated in the said figure, the cage has a circular section, although it may have any other oval or polygonal section, such a square or rectangular section; in such a case, the cross pieces (3) is arranged consequently.

The machine (1 ) has two housing heads (5) for the cross pieces (3) and a deposition device (6) of the spiral rod (4) around the cross pieces (3).

The cross pieces (3) and the spiral rod (4) interfere in the crossing points (1 1 ).

Figs. 2 and 3 illustrate the machine according to the present invention during two different working phases: fig. 2 illustrates the machine during the initial working phase, in which the cross pieces (3) are housed in the housing heads (5) and the deposition of the spiral rod has not started yet. The housing heads (5) are positioned one in front of the other one, with possibility to rotate around their axis (parallel to the axis of the cross pieces) and slide on tracks (7).

Moreover, the machine comprises an actuation motor (not shown) used to translate and rotate the heads.

The machine of the present invention is provided with a welding torch (8) and a vision device (9) that takes images of the area in front of the welding torch (8).

The vision system (9) and the welding torch (8) are fixed to a support (10) fitted to the frame of the device (1 ) or onto the ground.

Fig. 3 illustrates a more advanced phase of the machine compared to the one of fig. 2, in which the deposition of the spiral rod (4) around the cross pieces (3) has started, through the simultaneous translation and rotation of the heads (5) with respect to the deposition device (6) of the spiral rod (4).

The simultaneous translation and rotation generate the deposition of the spiral rod (4) according to a helix pattern.

Moreover, a control system of the welding torch (8) is provided (not shown). According to the present invention, the control system detects the passage of each crossing point (11) between a cross piece (3) and the spiral rod (4) in the welding area and switches on the welding torch (8).

The switch on of the welding torch (8) or, more generally, of a welding device is electronically controlled every time it is necessary during the passage of the crossing points (11 ) in the welding area.

The crossing points (11 ) can be either totally or partially welded.

Being automatically actuated by the electronic system, the quality of welding is higher than traditional welding made with mechanical systems, due to the very reduced tolerances. A further advantageous characteristic of the present invention is illustrated in fig. 4: the welding torch and the vision device (9) are mobile with respect to the support means (10) associated with them, by means of adjustment means (12, 13) that allow for finely adjust the position of the welding torch and the vision device (9). The adjustment means (12, 13) allow to move the welding torch (8) and the vision system (9) preferably according to two axes: a horizontal axis, that is basically parallel to the longitudinal axis of the cross pieces (3) and a vertical

axis perpendicular to the horizontal axis.

Advantageously, it allows for intervention if the crossing point (11 ) is not perfectly aligned with the welding torch (8), this being impossible in the machines according to the known art with fixed torch. Moreover, the adjustment can be automatically made by actuating the adjustment means (12,13) with the control system, either automatically or with the operator's control: in fact, the control system comprises at least one monitor to display images and means used by the operator to enter data or controls. The control system can be either completely automatic or controlled by the operator.

The vision device (9) can be a video camera or similar item. The control system can be actuated by the operator, who can display the images of the welding area in real time on the monitor to check the compliance of welding with the requirements, and eventually correct or repair welding by positioning the welding torch either manually or automatically. Advantageously, the machine can automatically weld the initial and final point of the spiral rod (4), which require the manual intervention of the operator with machines according to the known art. The control system can also be provided with a memory to store the position and quality of single welding operations.

Moreover, reinforcement rings (14) can be welded in external position to the reinforcement cage as illustrated in fig. 5, while this is not possible according to the known art. The machine of the present invention is not provided with the rollers or lever mechanisms that in the machine of the known art are needed to control the welding torch. Therefore, the lower volumes allow to make helixes of the spiral rod with pitch equal to the diameter of the rod, that is to say helixes or parts of helix with spiral rod wound as a ring (14), thus allowing the reinforcement rings (14) to be in external position to the cage.

Moreover, the present invention allows for obtaining stronger cages, with two or more cross pieces (3, 3A) in adjacent position, as shown in fig. 6.

This type of cages is impossible to obtain with the machines of the known art because, due to the mechanical lever mechanisms that control the welding torch, it is impossible to weld two cross pieces (3, 3A) in contiguous adjacent position. By means of the vision device (9) and perfect positioning of the welding torch (8), thanks to the adjustment means (12, 13) the machine of the present invention allows the control system to identify the presence of two contiguous adjacent cross pieces (3, 3A) and make the necessary welding between them and the spiral rod (4). With reference to figures 7 and 8, this description continues with a special embodiment of the aforementioned adjustment means for the position of the welding torch.

As mentioned above, the welding torch is fixed with a bracket (8a) to a first adjustment means (13) that consists in a slide designed to slide along a horizontal axis basically parallel to the longitudinal axis of the rods (3).

The first adjustment means (13) allows to adjust the working position of the torch (1 ) in longitudinal direction to exactly follow the working point in axial direction with respect to the cage. The slide (13) is supported by a second adjustment means (12), which consists in a second slide designed to slide with respect to the support frame (10) along a vertical axis basically perpendicular to the longitudinal axis of the cross pieces (3).

The second adjustment means (12) allows to adjust the working position of the torch (8) according to the distance of the welding point from the rotational centre of the cage, which varies according to the dimensions of the support section.

The embodiment shown in figures 7 and 8 is provided with a third adjustment means (14) that allows to fine-adjust the position of the torch (8) in radial direction perpendicular to the longitudinal axis of the rods (3). The third adjustment means (14) comprises a feeler connected to the adjustment means (13) by means of a bracket (14a), as well as a roller (14b) designed to roll on the external surface of the spiral rod (4).

The adjustment means (14) also comprises a linear actuator (14c) designed to bring the roller (14b) in contact with the rod (4).

The roller (14b) .is supported by a floating shelf (14d) hinged to the base of the bracket (14a), while the torch (8) is mounted on a bracket (8b) fixed to the floating shelf (14d), in such a way that the torch (8) can follow its smallest vertical oscillations determined by the contact between the spiral rod (4) and the roller (14b).

The third adjustment means (14) allows to offset the rapid movements of the rod (4) due to the morphological irregularities of the rod or of the entire cage. The present invention also relates to cages (2) for reinforced concrete piles or similar items, in which the cage (2) comprises at least three or more cross pieces (3) wound by a spiral rod (4) and provided with reinforcement rings (14), in which the reinforcement rings (14) are obtained in external position to the cross pieces from the same piece as the spiral rod (4), as shown in fig. 5, in which the reinforcement rings (14) are obtained from the same spiral rod (4) wound with helicoidal turns with pitch equal to the diameter of the rod. The present invention also relates to cages (2) for reinforced concrete piles or similar items in which the cage (2) comprises at least two or more cross pieces (3, 3A) in contiguous adjacent positions, as shown in fig. 6, provided with contiguous adjacent cross pieces (3, 3A) wound by a spiral rod (4).

The present invention also relates to a combination of the said characteristics, that is to say cages (2) for reinforced concrete piles or similar items in which the cage (2) comprises at least two or more cross pieces (3, 3A) in contiguous adjacent position, and provided with reinforcement rings (14), in which the reinforcement rings (14) are obtained in external position to the cross pieces from the same piece as the spiral rod (4).