GB2092091A - Apparatus for stacking elongate elements such as sections or bars - Google Patents

Abstract

Apparatus for stacking elongate elements (12) coming from a delivery conveyor (10) comprises a forwarding conveyor (30) onto which the elements (12) are deposited by a transfer device (15) and along which they are separated into two sets of groups by retractable stops (34, 37, 38) in such a way that alternate groups along the forwarding conveyor (30) belong to first or second sets, the groups of the second set having one fewer elements than the groups of the first set. The elements (12) are removed from the forwarding conveyor (30) and stacked by means of a first stacking transfer device (42) which has diamagnetic supports for the elements and which acts to transfer a group of elements (12) of the first set to a stacking station (49) in an upright orientation, and a second stacking transfer device (43) which has a magnetic head for retaining the elements and which acts to transfer a group of elements (12) of the second set into an inverted orientation over the immediately preceding group of elements of the first set. The second transfer device (43) then takes up the elements supported by the first transfer device (42), allowing the latter to be retracted from the stacking stations (49) prior to the elements being released onto a support at the stacking station. <IMAGE>

Description

SPECIFICATION Apparatus for bundling elongate elements such as sections or bars The present invention relates to apparatus for bundling elongate elements such as sections or bars. In particular the invention relates to improvements in apparatus which acts to withdraw sections or bars coming from one or more conveyors and then bundle them in ordered layers at an appropriate stacking and bundling station.

In the case of sections which have a shaped profile, for example an angle section, these are conveniently bundled together in layers in such a way that the profiles of sections in alternate layers face in opposite directions, that is one layer faces upwards and the next layer faces downwards, and so on. This facilitates the formation of a bundle comprising a plurality of layers of sections.

In the following specification reference is made particularly to the bundling of sections and to apparatus employed for bundling sections, but it is to be understood that the invention can also be applied to the bundling of other elongate elements such as rods and bars.

Various devices are known in the art for withdrawing sections from an arrival station and for bundling them by arranging them in layers of upright and inverted orientation alternately. In particular, one known bundling device includes a rotating circular conveyor which acts to withdraw the sections from an arrival station, and to transport them for deposition at a stacking station preparatory to bundling. All these operations being performed at substantially the same speed.

Because of this, when the sections are withdrawn and/or deposited, they can overlap each other because of the variation of the speed at which they arrive at the arrival station thereby preventing the proper functioning of the bundling device.

Moreover, such devices have to work at only a slow speed so as to permit an acceptable coordination of the functioning of the individual parts. One known device of this type forms the subject of Italian patent No. 1 018 429.

In such devices, and also in others, such as that which forms the subject of patent application No.

83358 A/78, several kinds of electromagnetic heads are employed to retain the sections, these cooperating together on the same bundling line; this makes the devices as a whole more complex and expensive, particularly because bundling devices which can achieve a high hourly output are usually equipped with several sets of electromagnetic heads which, together with the associated control and supply means which such heads require make the devices extremely costly.

For these reasons such bundling devices can be justified financially only in plants having a high volume output; they are not economical for small and medium size plants where it is not possible to justify from a financial standpoint the high capacity of the bundling device, which may substantially exceed that required for a small or medium size plant and which is a prime factor in their high cost.

The present invention seeks therefore to provide a device for bundling sections which will be both economical and very reliable; for this purpose it is important to ensure perfect coordination of the parts forming the device, and this can best be achieved by making use of means able to perform the different operations required to stack layers alternately right-side up and upside-down which means can move at a speed substantially suited to the specific operation being performed at the time in question.

The use of such means and also of special retainers which can be adjusted and which are suitably located on a conveyor bearing the sections makes it possible to prevent the sections from overlapping each other during transit from one part of the apparatus to the other.

The apparatus of the invention is capable of bundling a given number of sections in a selected orientation, and an important feature of the invention is that embodiments thereof, while still being fast enough to cope with the speed of arrival of the sections, are nevertheless not highly expensive.

According to the present invention there is provided apparatus for bundling elongate elements arriving from one or more delivery conveyors, in which bundling is effected with alternate layers of elements inverted, comprising a forwarding conveyor, means for collecting a plurality of elements from a delivery conveyor, means for separating the elements into successive groups on the forwarding conveyor, with a predetermined number of elements in each group, first transfer means operable to transfer alternate groups of elements in the upright orientation from the forwarding conveyor to a stacking station, the transfer means having diamagnetic supports for the said groups of elements, and second transfer means operable to transfer to the stacking station alternate groups of sections interspersed between the groups transferred by the said first transfer means, the second transfer means having magnetic supports for the elements and being operable to turn the elements through 1800 in transferring them from the forwarding conveyor to the stacking station whereby to deposit them, inverted, over the layer of elements positioned in the upright orientation by the said first transfer means.

Embodiments of the present invention thus require only one set of electromagnetic heads cooperating with suitable collection and transfer means for each bundling line. Moreover, the improvements of the present invention enable several bundling devices, disposed parallel to each other, to be operated from a single control position.

One embodiment of the invention will now be more particularly described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic side view of bundling apparatus formed as an embodiment of the present invention; Figure 2 is a plan view from above of the apparatus shown in Figure 1; and Figure 3 is a diagrammatic side view of a part of the embodiment of Figures 1 and 2 cooperating with a collection and discharge device which differs from that shown in Figure 1.

In all the figures of the drawings the same parts, or parts performing the same functions, have been indicated with the same reference numerals.

Referring now in particular to Figure 1 and 2 there is shown a delivery conveyor 10, in this instance a roller conveyor, which is operated by suitable drive motors 11, and which conveys a plurality of sections 12 in a direction substantially perpendicular to the length of a conveyor line of the bundling apparatus 13 constituting the embodiment of the invention. For clarity in the drawings the sections have been shown as angle sections, but this shape is not restrictive and the bundling apparatus 13 of the invention can be used to bundle sections or bars having any desired profile.

The sections 12 arrive on the conveyor 10 so as to coincide with the bundling apparatus 13, and are transferred onto a forwarding conveyor 14 by collection and transfer means 1 5 which substantially comprise a movable component 19 which can run along an elongate guide structure 16 which is provided with guides 17 having a toothed rack 24 formed in the lower edge thereof.

The said movable component 19 of the transfer means 15 is constituted by a carriage 20 equipped with wheels or slides 25 which can roll or slide along the guides 17. The carriage 20 has arms 26 that can extend into the crosswise gaps in the roller conveyor 10 when the carriage 20 is at the right hand end of its travel as seen in Figure 1. On either side of the conveyor 10 are located shaped structures 27 which delimit the sides of the delivery conveyor 10 and constitute an appropriate border therefor. The carriage 20 is driven by an electric motor 28 via one or more toothed wheels 29 meshing with the rack 24 on the guide 17. The toothed wheels 29 may be keyed onto the shaft of the electric motor 28 or may be connected thereto by belts, transmission shafts with universal joints or other transmission means.The movable guide structure 1 6 can pivot at one end 21 about a pivot axis 18, and can be raised at its other end 121 by a lever device 22.

The lever device 22 can be operated by means of electromechanical linear actuators or other iike means connected thereto by connecting rods. In alternative embodiments the movable guide structure 1 6 of the transfer means 1 5 may be lifted or rotated by the direct action of a linear or a rotary actuator, perhaps connected thereto by rack means or lever means.

In operation a number of parallel sections 12 reach a position corresponding to the bundling apparatus 13, they are contacted by the arms 26 raised by rotation of the guide structure 1 6 about the axis 18 upon actuation of the lever linkage 22, 23. The sections 1 2 are then drawn onto the forwarding conveyor 14 by displacement of the carriage 20 along the guides 1 7.

The forwarding conveyor 14 comprises an endless belt or chain 30 kept under tension by a plurality of pulleys 31, and driven by a drive motor 32 via further belt and pulley means 33. The advance of the sections 1 2 moved by the forwarding conveyor 14 towards a stacking and bundling zone is controlled also by a separator catch 34, which is operated by a linear actuator 35 via suitable levers 36. In order to prevent the sections 12 from overlapping each other on the belt 30 when stopped against the separator catch 34 this belt 30 is inclined upwardly in the direction of movement of the sections (that is from right to left as viewed in Figure 1) by an angle great enough to prevent such overlapping.The operation of the catch 34 is synchronised with that of two similar retracting abutment stops 37 and 38 which are positioned at spaced intervals downstream from the catch 34 to form three transit zones on the belts 30 for the sections 1 2.

These transit zones comprise a first zone 39 along which the flow of sections 12 is variable this is followed by a zone 40 in which a given number of sections 12 can be collected. This is done by making the retracting catch 37 move forwards or backwards along the conveyor 30 to selected positions. In practice the catch 37 is caused to move by a distance corresponding to one section between each retracting movement so that, alternately a number N and a number N - 1 of sections 12 is passed from the zone 39, the number N being determined by the preliminary setting of the catch 34. Such reciprocating movement is carried out by operating linear actuators (not shown) which control the longitudinal position of the retracting catch 37.

Thus a number N and a number N - 1 of the sections are moved alternately into the third zone 41 of the conveyor 30. This third zone 41 is a transfer zone from where the sections are transferred onto a stacking station 48.

Transfer of alternate sets of N or N - 1 sections is effected alternately by a first transfer mechanism 42 and a second transfer mechanism 43. The first transfer mechanism 42 is substantially identical to the transfer mechanism 1 5 described above but facing the opposite direction and located at the other end of the conveyor 30. The transfer mechanism 42 has two arms like the arms 26 of the transfer means 1 5, but made of diamagnetic material.

The two transfer mechanisms 42 and 43 are both movable between respective first positions, under the conveyor 30, in which they are shown in solid outline in Figure 3, and second positions over a stacking station 48, in which they are shown in solid outline in Figure 1 and in broken outline in Figure 3. The movement of the first transfer mechanism 42 is synchronised with that of the conveyor 30 and the abutment stops 37, 38 in such a way that it transfers the groups containing N sections to the stacking station 48 in an upright orientation.

Following this transfer a group of N - 1 sections 1 2 which arrives subsequently at the zone 41, having been allowed to reach there by the retracting abutment stops 37 and 38, is withdrawn from the zone 41 and rotated to an inverted position at the stacking station 48 by the second transfer mechanism 43. The sections 12 are held magnetically on one face of a magnetic plate of the second transfer mechanism, and this is then turned over so that the N - 1 sections are placed above the N sections already located in position by the diamagnetic arm of the first transfer mechanism 42.

In this position, because of the magnetisation of the magnetic plate 43, both the layers of sections 12 remain attracted by the magnetic plate 43.

The diamagnetic arm transfer mechanism 42 is then withdrawn and returned to its initial position 44.

The magnetic plate 43 is then demagnetised so as to transfer the sections 12 onto a collection support 49 (Figures 1 and 2) in two layers 48 containing the numbers N and N - 1 of sections 12, the number N of sections being the right way up and the number N - 1 of sections being inverted respectively. The magnetic plate transfer means 43 are then returned to the initial position.

The collection support 49 is lowered, after each pair of layers has been loaded onto it, a distance determined by the operation of suitable actuators 50, so as to create between the layer 51 of sections 12 just deposited on it and the position occupied by the transfer means, a space great enough for the introduction of the diamagnetic arm means 42 holding the next layer of sections 12 to be deposited.

Various devices can be used for discharging the formed bundle 51 from the bundling machine. In particular, Figures 1 and 2 show a discharge device 52 which comprises a carriage 53 running on guides 54. This carriage 53, which carries the collection surface 49, is moved transversely of a discharge conveyor 57, in this instance a roller conveyor, by the operation of a transverse transport mechanism 55 worked by one or more suitable drive motors 56.

In operation the collection surface 49 is lowered down to or below the supporting surface of the conveyor 57, by means of a linear actuator 50, so as to be able to transfer the bundle of sections 12 laterally onto the roller conveyor 57.

To repeat the bundling cycle, the carriage 53 is brought back to its starting position and the collection support 49 raised to a level such as to be able to receive the new layers 51 of sections 1 2.

In the alternative embodiment of Figure 3 the discharge device 52 comprises linear actuators 50 able to move the collection support 49 vertically, these actuators 50 consisting of an electric motor cooperating through belt means or rack means with the collection support 49. A substantially upright support structure 58 carries the actuators 50. In operation a bundle 51 of sections 12 is deposited on the roller conveyor 57 simply by moving the support 49 vertically down to a level below the support surface of the roller conveyor 57, the support 49 in this case comprising arms which can pass between adjacent rollers of the conveyor 57.

To return to the initial position for the start of a new bundling cycle, the collection support 49 is simply made to re-ascend until it reaches its starting position.

Although only one bundling apparatus has been described, several bundling apparatuses 10 can be disposed parallel to each other and be operated with a single set of controls, as indicated schematically in Figure 2.

Claims (6)

1. Apparatus for bundling elongate elements arriving from one or more delivery conveyors, in which bundling is effected with alternate layers of elements inverted, comprising a forwarding conveyor, means for collecting a plurality of elements from a delivery conveyor and for transferring them onto the forwarding conveyor, means for separating the elements into successive groups on the forwarding conveyor, with a predetermined number of elements in each group, first transfer means operable to transfer alternate groups of elements in the upright orientation from the forwarding conveyor to a stacking station, the transfer means having diamagnetic supports for the said groups of elements, and second transfer means operable to transfer to the stacking station alternate groups of sections interspersed between the groups transferred by the said first transfer means, the second transfer means having magnetic supports for the elements and being operable to turn the elements through 1800 in transferring them from the forwarding conveyor to the stacking station whereby to deposit them, inverted, over the layer of elements positioned in the upright orientation by the said first transfer means.

2. Apparatus as claimed in Claim 1, in which the means for separating the elements into groups comprises abutment stops which are movable between raised and lowered positions to intercept the elements or to allow them to pass along the forwarding conveyor.

3. Apparatus as claimed in Claim 1 or Claim 2, in which the said first transfer means are movable between a first position beneath the forwarding conveyor and a second position over a stacking support of the stacking station, the said second transfer means being movable from a first position under the forwarding conveyor to an inverted position over the first transfer means in its second position.

4. Apparatus as claimed in Claim 3, in which the second transfer means acts, when in its second position to take up the elements carried by the first transfer means allowing this latter to return to its first position before the elements are deposited at the stacking station.

5. Apparatus as claimed in any preceding Claim, in which the said separating means acts to separate the elements into consecutive groups in such a way that adjacent groups have a number of elements differing by one element, alternately one more and one less than the number of elements in the preceding group, so that when alternate groups are inverted for stacking their profiles match those of the non-inverted groups in the stack.

6. Apparatus for bundling elongate elements substantially as hereinbefore described with reference to the accompanying drawings.