An apparatus for entwining a sheaf of rod or bar shaped articles with at least one metal wire, which rod shaped articles on a supporting plate are piled upon each other for forming at least one wall of articles, or of articles arranged on the supporting plate along each other.

The entwining of sheafs of rod shaped articles, e.g. reinforcement steels, has hitherto been carried out manually. The entwining should be firm to prevent the bundled articles from slipping in relation to each other during the transport of the sheafs.

From EP 0 511 870 is known an apparatus able of packing a pallet and a loading arranged on the pallet with a wrapping film and a film rope.

The pallet is guided to the apparatus on a roller path, which below the apparatus comprises a platform on which the pallet can be lifted and lowered, and having a supporting face, the contour of which is within the contour of the pallet when the pallet is lifted on the platform.

The apparatus may guide a roll of wrapping film of plastic so that the roll rotates around the loading and the pallet and so that the roll is lifted and lowered in such a way that a film or a film rope in spiral shaped lengths is wrapped around the pallet and its loading.

The wrappings may follow spiral shaped lengths extending beyond the top surface of the loading and the bottom surface of the pallet in such a way that areas along edges or corner areas on the top surface of the loading and the bottom surface of the pallet are covered by film and film rope, respectively. The apparatus may fold the wrapping film to a rope so that the wrapping in a selected order can be carried out with a film or a film rope, respectively.

The apparatus thus known is not suitable for use by the entwining of rod shaped articles mentioned above, the longitudinal directions of the rod shaped articles being parallel to the bottom of the pallet, since the apparatus is prevented from carrying out a wrapping extending below a sheaf of rod shaped articles from one side to the other of the sheaf

and above the supporting area of the pallet.

The known apparatus is thus prevented from applying a metal wire by the entwining of a sheaf of rod shaped articles which on a supporting plate is piled upon each other for the forming of at least one wall of articles, or of articles so arranged on the supporting plate along each other in such a way that the articles independent of a pallet can be pressed relatively firmly against each other.

It is the purpose of the invention to provide an apparatus, eliminating said drawbach by the known apparatuses.

This purpose is achieved with an apparatus for entwining of a sheaf of rod shaped articles with at least one metal wire, which articles on a supporting plate are piled upon each other for the forming of at least one wall of articles, of of articles arranged on the supporting plate along each other, said apparatus being characterized in that it comprises two parallel metal wire handling arms being displaceable in their longitudinal direction, that the apparatus is so adapted that the two wire handling arms may be advanced a predetermined diestance on each side of and a small distance past the lower end of a sheaf of articles arranged on a supporting plate, and that the wire handling arms at their ends each comprises an encircling part, each adapted to catch an area of a conveyed metal wire part having a length which is apportioned for an entwining of the sheaf and is made from a material with such resilient properties that the metal wire after a twisting can maintain its twisted form, and further¬ more so that the wire handling arms together with the metal wire part may be conveyed so far backwards that the center zone of the metal wire part engages the one end of the sheaf, and furthermore so that the two ends of the metal wire parts are conveyed backwards along respective sides of the sheaf and upwards over the other end of the sheaf, and finally so that the wire handling arms along with the two ends of the metal wire part can be caused to rotate around an axis which is parallel with and located between the wire handling arms in such a way that the two ends of the metal wire part are twisted around each other above the other end of the sheaf,

until the metal wire part is tightly twisted around the sheaf.

The apparatus is thus constructed to copy and carry out the operations hitherto carried out manually by a firm entwining of rod shaped articles with a metal wire. The apparatus according to the invention can be characterized in that the metal wire guiding means are arranged at the side of the supporting plate turning away from the sheaf resting on the supporting plate, which guiding means can guide the metal wire to a position in which the metal wire part is to be engaged by the encircling parts of the wire handling arms.

Thus, a safe "threading" of the encircling parts of the wire handling arms is obtained.

The apparatus according to the invention can be characterized in that a metal wire conveying mechanism and a wire cutting mechanism are arranged upstream of the one guiding means, both of which mechanisms are displaceable in the metal wire direction.

Thus, it is achieved that the metal wire part can be red in a length and be placed in a position which is adapted to the height of the sheaf to be entwined.

The apparatus according to the invention can be characterized in that the wire handling arms are arranged displaceably in their longitudinal direction in a rotor in a bearing block. Thus, a simple construction is achieved, whereby the rotor serves two purposes, namely as guiding means for the wire handling arms and as a means to initiate rotation of the wire handling arms.

The apparatus according to the invention can be characterized in that the bearing block is secured to a swivel arm which is secured to a slide block, which in turn is pivotable around and displaceable along a column, the axis of which is parallel to the axes of the wire handling arms.

Thus, it is achieved that the apparatus can be displaced towards and away from its position above the supporting plate in order to provide space for the handling of a sheaf to and from the supporting plate. Furthermore, it is achieved that the distance of the apparatus from the suppor-

ting plate can be adapted to the height of the sheaf to be entwine .

The apparatus according to the invention can be characterized in that it is provided with a pneumatically controlled driving mechanism which can be caused to displace the wire handling arms in their longitudinal direction.

Thus, the control of the wire handling arms' movement is facilitated.

The apparatus according to the invention can be characterized in that a counter pressure plate with an opening providing space for the rotation fo the wire handling arms around the axis of the rotor is secured to the bearing block at the side turning towards the supporting plate for a sheaf of articles. The counter presure plate may cause the articles to be pressed firmly together before the entwining of the sheaf.

The apparatus according to the invention can be characterized in that a pressure pad has been secured to the lower side of othe bearing block, which pressure pad is made of a material having substantially the same resilient and frictional properties as nylon, and which furthermore has holes, through which the wire handling arms may pass, said holes having a cross section of the same shape and a little larger than the cross section of the wire handling arms.

With such pressure pad those parts of the metal wire part extending beyond the sides of the wire handling arms, when the wire handling arms are drawn as far up as possible, are pressed firmly against the pressure pad. The engagement of the metal wire ends with the encircling parts of the wire handling arms can thus be maintained in the en¬ circling parts while the metal wire sliding on the plate during the rotation of the metal handling arms which causes the twisting together of the two metal wire ends. Thus, it is avoided that the metal wire ends are released from their engagement with the end of the wire handling arms, before the metal wire part: entwining the sheaf is sufficiently tensed. The invention will now be described in more detail

with reference to the drawing in which

Fig. 1 shows a, side view, partly in section, of the apparatus in its position ready for receiving a pile of articles for entwining, Fig. 2 the apparatus of Fig. 1 with the wire handling arms of the apparatus ready for pulling the metal wire ends upwards around a wall of piled articles when the metal wire is ready therefor, and Fig. 4 the apparatus of Fig. 3 wherein the cut off piece of the metal wire is arranged firmly around the wall, ready for entwining.

As an example of articles to be bundled and entwined is reinforcement steels bent into right angles for forming an rectangle. Said rectangular articles are piled or stacked for the formation of a box-like bundle having four walls formed of reinforcement steels arranged one upon the other.

The purpose may now be to entwine one or more sides of said box walls with a metal wire part extending from above beyond the upper reinforcement steel in a box wall and downwards along one side of this wall, below the lower reinforcement steel in this wall, upwards along the other side of this wall and past the upper reinforcement steel in the wall, and the free ends of which metal wire above the wall are twisted around each other to such an extent that the reinfor¬ cement steels in the wall are pressed firmly against each other.

The apparatus of Fig. 1 has a bearing block 2 which with a swivel arm 12 is connected to a displaceable and pivotable slide block 10 carried on a support 11. The appara¬ tus may be displaced towards or away from the supporting plate 18 for a wall of reinforcement stells and be pivoted around the support 11 and away to a position beside the supporting plate 18. A rotor is arranged in the bearing block 2 which bearing block •supports two wire handling arms 6 being dis¬ placeable in their longitudinal direction by means of a pneumatically controlled driving mechanism 15. The rotor is

connected to a driving motor 5 via a chain drive 1.

A pressure pad 16 with holes for the passage of the wire handling arms 6 are secured to the bearing block 2 below the bearing block. A counter pressure palte 3 which is able to press the reinforcement steels in a wall together against the supporting plate 18 in the support plate 13 below the apparatus is secured below the bearing block 2. The counter pressure plate 3 has an incision within which the wire handling arms 6 may rotate together around the rotor axis. A part of the support plate 13 comprises the supporting plate 18, which may support a wall of reinforcement steels and having an incision 19, through which the wire handling arms 6 may pass downwards in order to engage the metal wire part 20, and together with the metal wire part 20 may pass upwards when the wire handling arms 6 are to pull the metal wire parts '20 upwards along the sides of the wall of reinforcement steels.

Below the support plate 13 the metal wire may be conveyed foward by the conveyor mechanism 9 and may be guided forwards through guiding means 7 to the area in which the encircling parts 14 of the wire handling arms 6 should be caused to encircle the metal wire part 20. The metal wire is guided forwards by the conveying mechanism 9 in a length and to a position fitting to the wall of reinforcement steels 4 to be entwined, whereupon it is cut off by the wire cutting mechanism 8. The metal wire can be fed from a metal wire roll 21.

By the apparatus of Fig. 2 a sheaf of reinfor¬ cement steels 4 to be entwined is arranged on the support plate 13. One wall of the sheaf of reinforcement steels 4 is arranged in a plane comprising the rotor axis and is perpendi¬ cular to a plane comprising the axes of the wire handling arms 6 and resting upon the supporting plate 18.

By the apparatus of Fig. 3 the slide block 10 is moved downwards on the support 11, whereby the reinforcement steels 4 are pressed firmly against each other between the counter pressure plate 3 and the supporting plate 18, and whereby the ends of the metal wire handling arms 6 are moved

down below the support plate 13 for engagement with the metal wire part 20, which is fed forwards under the support plate 13 by the conveying mechanism 9 and cut off by the wire cutting mechanism 8. The encircling parts 14 may be slotted so that the metal wir 20 can be guided into the encircling parts 14 from the sides of the wire handling arms 6. The ends of the wire handling arms 6 can be shaped as a cone or a half cone, the conical sides of which turn against each other. The conical sides serve to guide the metal wire part into the encircling parts 14 of the wire handling arms. The cone sides may furthermore push away possible obstructions to the wire handling arms 6 on their way downwards past the sides of a sheaf 4.

By the apparatus of Fig. 4 the reinforcement steels 4 are pressed firmly against each other between a coun¬ ter pressure plate 3 and the supporting plate 18, and the wire handling arms 6 each being in engagement with an end of the metal wire part 20, are pulled up around the wall of reinfor¬ cement steels 4 to such a level that those parts of the metal wire part 20 e ^' xtending beyond the sides of the wire handling arms 6, are pressed against the pressure pad 16. Thereupon the rotor is caused to rotate. The wire handling arms 6 is thereby caused to rotate around the rotor axis and to twist the two ends of the metal wire part 20 together. During the twisting the two ends of the metal wire part 20 are pressed so firmly against the pressure pad 16 that the metal wire ends do not slide out of engagement with the encircling parts 14 of the wire handling arms 6. The rotation of the rotor is controlled so that the rotation stops when the metal wire part 20 lies firmly around the wall of reinforcement steels 4, and when the torque necessary for the twisting exceeds the corresponding limit. Thereupon the wire handling arms 6 may be moved downwards a certain distance. Thereby the metal wire ends are bent downwards along the wall of reinforcement steels 4 and slips out of the engagement with the encircling parts 14 of the wire handling arms 6. The apparatus may now be lifted and swung aside, whereupon the sheaf of reinforcement steels may be removed or turned, if another wall in the sheaf should be

entwined .

An upwardly slotted horizontal tube may be arrang¬ ed between the metal wire handling arms 6 and below the supporting plate 18, which tube may serve as guiding means 7 for a metal wire part when it is guided forwards to a position below the wire handling arms 6, from which position the wire handling arms can pull the metal wire part 20 upwards through the slot of the guiding means 7.