Description
METHOD FOR MAKING REINFORCEMENT IRONS
Technical Field
[01 ] The present invention regards a method for making reinforcement irons for reinforced concrete.
Background Art
[02] It has been known that, in order to make metal stirrups or more generically reinforcement irons for reinforced concrete, automatic machines named wire bending machines or wire folding machines are used. Such wire bending machines or wire folding machines are usually provided with means for drawing metal profiles used to obtain the reinforcement irons; with means for cutting portions of metal profiles necessary to shape single reinforcement irons, and with a folding head which realizes the folding of such portions of profile according to the desired geometry.
[03] The operating mem bers of the wire folding machines are arranged in sequence, along the feed axis of the metal profiles. Such operating members, according to the technical embodiments, can be arranged on one or more work axis, but are generally arranged in positions close to each other. This determines that, during the folding steps, the metal profiles can interfere with parts of the machine protruding with respect to the work plane, as for example the housing of drawing and cutting means, which raise them at least in part from the theoretical formation plane. As a consequence, the metal profiles being worked undergo undesired stresses which tend to make the obtained reinforcement irons crooked. Vice versa applications exist for which it is specifically required that the reinforcement
irons be substantially coplanar, so the cited defect is poorly tolerated.
[04] Such a drawback results obviously more sensible if reinforcement irons of large dimensions have to be made, for example U-shaped, for which the radius of travel of the profiles in folding step is wider.
[05] Wire folding machines have been also known to be provided with auxiliary drawing means arranged downstream of the folding head, according to the feed direction of the metal profiles, and suitable to handle the portions of metal profile designed to shape single reinforcement irons after cutting, as illustrated for example in patent EP 379043. Such wire folding machines specifically enable to make reinforcement irons having one or more folds in both ends of the same reinforcement irons.
[06] Patent IT 1242690 discloses a wire folding machine wherein the aforesaid auxiliary drawing means are mobile between a foldaway position, a work position placed substantially at the level of the work plane, and a position further protruding from the work plane to shift the profile above the folding head, freeing it therefrom.
[07] Nevertheless the cited solutions do not solve the problem of making reinforcement irons substantially coplanar, in particular having large dimensions.
Disclosure
[08] The task of the present invention is that of solving the aforementioned problems, devising a method which allows to perform in an optimal way the making of reinforcement irons for reinforced concrete, in particular enabling the realization of substantially coplanar reinforcement irons.
[09] Within such task, it is a further scope of the present invention that of
providing a method which enables to make reinforcement irons for reinforced concrete also having large dimensions.
Another object of the present invention is that of providing a method for making reinforcement irons which is realizable by means of an apparatus having a simple conception, a securely reliable functioning and versatile use, as well as relatively economic cost.
The cited scopes are attained, according to the present invention, by the method for making reinforcement irons for reinforced concrete according to claim 1 .
According to the present invention, the method for making reinforcement irons for reinforced concrete provides to carry out the measured cutting of the portion of metal profile designed to shape the reinforcement irons and to move said cut portion of the metal profile in a position distanced from the work plane of the machine, so as to perform one or more folding steps of the aforesaid portion of metal profile without interfering with parts of the machine protruding from such work plane.
Suitably such displacement of the aforesaid portion of metal profile is obtained moving in an operating position protruding from the work plane the folding head and auxiliary drawing means arranged downstream of the folding head, which are suitable to engage the same portion of metal profile.
Suitably the method in hand provides to actuate the aforesaid auxiliary drawing means to perform the shifting of the cut portion of the metal profile in a direction opposite to the feed direction, for a predeterm ined length tract, and to perform through the folding head at least one folding of the cut
portion of the metal profile.
[15] In particular the method provides to repeat the said steps of actuating the auxiliary drawing means to perform the shifting of the cut portion of the metal profile in a direction opposite to the feed direction and to perform through the folding head a folding of the cut portion of the metal profile for a number of times equal to the number of folding to be performed on said cut portion of the metal profile to obtain the reinforcement iron.
Description of Drawings
[16] Details of the invention shall be more apparent from the detailed description of a preferred embodiment of the method for making reinforcement irons for reinforced concrete according to the invention, illustrated for indicative purposes in the attached drawings, wherein:
[17] figure 1 shows a perspective view of a folding area of a wire folding machine designed for making reinforcement irons for reinforced concrete;
[18] figures 2 - 9 show the same perspective view of the wire folding machine, in successive operating steps of the method according to the present invention;
[19] figures 10 - 14 show a perspective view of a different embodiment of the apparatus for making reinforcement irons, in successive operating steps of the method according to the present invention;
[20] figures 15 - 19 show a perspective view of a further embodiment of the apparatus for making reinforcement irons, in successive operating steps of the method according to the present invention.
Best Mode
[21 ] With particular reference firstly to figures 1 - 9, the folding area of a
machine for folding metal irons 2 is indicated in its entirety with 1 . The wire folding machine is provided, in a known manner, with a folding head 3 which is mobile between a retracted disengagement position underneath the work plane 1 0 of the machine and an operating position suitably protruding from the aforesaid work plane 10. The folding head 3 provides a folding pin 4 which is carried rotatable about an eccentric rotation axis, substantially perpendicular to the work plane 10 of the machine. The folding head 3 further provides a mandrel 5 constituted by a couples of half moon shaped bodies 5a, 5b, specular to each other; the shaped bodies 5a, 5b define a channel 6 longitudinal, in operating position, to the feed axis of the profiles 2. Obviously the shaped bodies 5a, 5b can have a profile different from the represented one, in particular to make bilateral folding.
[22] The metal profiles 2 are fed to the folding head 3, in the direction indicated with the arrow A, through drawing means known per se, which are not represented in the drawings. Such drawing means are contained inside a protection housing 1 1 , protruding from the work plane 10 of the machine, upstream of the folding head 3.
[23] Downstream of the folding head 3, according to the feed direction A of the metal profiles 2, are provided auxiliary drawing means 7 aligned with the drawing means arranged upstream of the folding head 3. The auxiliary drawing means 7 are mobile between a disengagement position retracted underneath the work plane 10 of the machine, a first operating position placed substantially at the level of the work plane 1 0, and a second operating position further protruding from the mentioned work plane. The auxiliary drawing means 7 consist of couples of counter rotating drawing
wheels 8, suitably driven. As better specified thereafter, the metal profiles 2 engaged by the auxiliary drawing means 7 in the aforesaid first operating position move on the work plane 10, whereas when the auxiliary drawing means 7 are shifted in the aforesaid second operating position, the metal profiles 2 result suitably distanced from the work plane 10.
Upstream of the folding head 3 and adjacent thereto, are arranged cutting means 9 for the metal profiles 2, for example of the shear type comprising a fixed blade and a mobile blade.
The method for making reinforcement irons for reinforced concrete is described thereafter.
At the beginning of every cycle for making a reinforcement iron, the folding head 3 a nd the auxi l iary d rawi ng m eans 7 are arranged i n the disengagement position, retracted underneath the work plane 10 of the machine (fig. 1 ) or in any case in a position such as not to interfere with the profile during the feeding thereof. This allows to feed a metal profile 2 to be folded according to the feed direction A, on the work plane 10, without interfering with the folding head 3 and with the auxiliary drawing means 7; the metal profile 2 is fed for a predefined length tract, until jutting out the aforesaid auxiliary drawing means 7.
The auxiliary drawing means 7 are then displaced in the first operating position placed substantially at the level of the work plane 10, to engage the portion of metal profile 2 fed before (fig. 2), tightening the wheels on the same metal profile 2. Then the measured cut of the portion of metal profile 2 designed to shape a reinforcement rod is carried out.
The auxiliary drawing means 7 are then displaced in the second operating
position protruding from the work plane 10, to distance the cut portion of the metal profile 2 from the same work plane (fig. 3). Simultaneously the folding head 3 is moved in the operating position protruding from the work plane 10, wherein it is engaged by the metal profile 2. In particular, the cut portion of the metal profile 2 crosses the channel 6 defined between the shaped bodies 5a, 5b of the folding head 3 and gets engaged between the drawing wheels 8 of the auxiliary drawing means 7.
In this condition, the auxiliary drawing means 7 are actuated to perform the shifting of the cut portion of the metal profile 2 in a direction opposite to the feed direction A, for a predetermined length tract (fig. 4). In such a shifting step, the cut portion of the metal profile 2 is on a plane distanced from the work plane 10 by a tract sufficient to avoid the interference with the parts of the machine protruding from the work plane 10, in particular the housing 1 1 of the drawing means upstream of the folding head 3.
Through the folding head 3 is successively operated at least one fold of the cut portion of the metal profile 2 to obtain the reinforcement iron 20, folded in the desired shape, for example U-shaped.
In particular, it is provided to carry out a first fold of the cut portion of the metal profile 2, for example squaring (fig. 5). Successively, after having taken back the folding pin 4 in the starting position, by means of the auxiliary drawing means 7 a further shifting of the cut portion of the metal profile 2 is carried out in a direction opposite to the feed direction A, for a predetermined length tract (fig. 6). Then a further folding of the metal profile 2 is performed to obtain the reinforcement iron 20 (fig. 7).
Simultaneously, in a suitable step relationship with the actuation of the
folding head 3, the auxil iary drawing m eans 7 are displaced in the disengagement position to free the work plane 10 and allow to complete the aforesaid further folding (fig. 8) thus avoiding the interference with the housing of the auxiliary drawing means 7 which, in grip position on the profile, protrude from the work plane. This operation can be carried out in any moment before the profile interferes with the members protruding from the work plane. In the case illustrated for indicative purpose two 90° folds are provided, but in the same way a single 180° fold could be made.
It is to be observed that in folding step the channel 6 defined between the shapes bodies 5a, 5b of the folding head 3 acts as a necessary contrasting member for the portion of profile 2 arranged according to the feed axis, downstream of the operational area of the folding pin 4.
At last, it is provided to displace the folding pin 4 and the folding head 3 in the disengagement position to enable the discharge of the so obtained reinforcement iron 20 (fig. 9).
In figures 1 0 - 14 a different embodiment of the apparatus for making reinforcement irons is illustrated, wherein the mandrel of the folding head 3 is constituted by a cylindrical shaped pin 12 arranged according to the rotation axis of the folding head 4. The steps for making reinforcement irons substantially reproduce the ones previously described.
In particular, once performed the first folding about the mandrel 12 (fig. 10), the portion in progress of the metal profile 2 is shifted in a direction opposite to the feed direction A (fig. 1 1 ) to prearrange the profile for the realization of a second folding (fig. 12). Before the profile in progress interferes with the housing of the auxiliary drawing means 7, these latter are opened and the
only upper part is retracted underneath the work plane. In such a way the interference with the profile in progress is prevented, while the lower part of the auxiliary drawing means 7 continues carrying out the necessary function of contrasting the profile during the folding. Once the second folding is com pleted (fig. 1 3), the folding head 3 is displaced in the disengagement position to allow the discharge of the so realized reinforcement iron 20 (fig. 14).
[37] In figures 1 5 - 1 9 a further embodiment of the apparatus for making reinforcement irons is illustrated, wherein between the folding head 3 and the auxiliary drawing means 7 at least one contrasting member is arranged. In particular, in the illustrated case is provided a couple of contrasting members 13, 14 mobile independently from each other. While performing the first folding, a first contrasting member 1 3 is taken in an operating position protruding from the work plane to engage the rod 2 along the feed axis (fig. 1 5). The contrasting member 1 3 can remain in the operating position or otherwise be displaced in a disengagement position retracted if it should create problems to the handling of the profile 2 (fig. 16). The contrasting member 1 3 is once again displaced in the operating position protruding from the work plane to enable the carrying out of a folding in the profile wherein the same profile would interfere with the housing of the auxiliary drawing means 7 (fig. 17). In fact during such a folding step, the auxiliary drawing means 7 are possibly displaced in the disengagement position or in a position of non interference with the metal profile 2, to allow the completion of the same folding (fig. 18). The folding pin 4, the folding head 3 and the contrasting member 13 are at their turn successively
displaced in the disengagement position to allow the discharge of the so realized reinforcement iron (fig. 19).
The second contrasting member 14, arranged at the opposite side with respect to the feed axis of the metal profiles 2, is actuated in case folds in opposite direction with respect to the previous ones have to be made.
The method in hand attains the scope of carrying out in an optimal manner the making of reinforcement irons for reinforced concrete, also with large dimensions.
A characteristic of the method in hand consists in the fact of allowing the realization of substantially coplanar reinforcement irons.
Such a result is obtained substantially thanks to the inventive idea of performing one or more folding steps on a portion of the metal profile which is cut and handled by auxiliary drawing means arranged downstream of the folding head, without interfering with parts of the machine protruding with respect to the work plane, in particular the housing of the drawing means arranged upstream and downstream of the folding head. Therefore the metal profile in folding step does not undergo undesired stresses, and the so obtained reinforcement irons turn out to be coplanar as desired.
The apparatus described for indicative purpose for actuating the method in hand is susceptible of numerous modifications and variants according to the diverse exigencies.
In particular it is possible to provide the use of the method in hand also in machines wherein the operating members are distributed on two work axis, for example of the type illustrated in patent EP 0865842. In this case it is possible to provide for not having to displace the metal profile to be folded
in a position distanced from the work plane.
In practice, the embodiment of the invention, the materials used, as well as the shape and dimensions, may vary depending on the requirements.
Should the technical characteristics mentioned in each claim be followed by reference signs, such reference signs were included strictly with the aim of enhancing the understanding 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.