EP1533387A1

EP1533387A1 - Device to be used during the transfer of leathers between two conveyor belts and for depositing them on pallets, horses and the like

Info

Publication number: EP1533387A1
Application number: EP04025780A
Authority: EP
Inventors: Luigi Boschetti; Arnaldo Balestro
Original assignee: Tanmac Srl
Current assignee: Tanmac Srl
Priority date: 2003-11-11
Filing date: 2004-10-29
Publication date: 2005-05-25
Also published as: ITVI20030222A1

Abstract

The invention concerns a device to be used during the transfer of leather (4) between two conveyor belt and for depositing them on pallets (6), horses and the like, suitable for preventing the formation of creases, depressions, ridges and other imperfections, in particular during the end step of depositing, when the final portion of the leather (4), detaching from the conveyor belt (3), tends, due to the very nature of the product, to remain raised or, in the worst of conditions, to curl up. Such a device is characterised in that it comprises a small sliding band (10), in a closed loop, kept under tension through at least two takeup pulleys (11,12), arranged parallel to each other and with the axes arranged in the transversal direction with respect to the advancing direction of the leather, which can slide in the interspace defined between the surface of the conveyor belt (3) and the surface of the small band (10), said small band acting on the entire length of the leather, during the depositing step thereof.

Description

The present finding concerns a device to be used for transferring leathers between two conveyor belts and for depositing them on pallets, horses and the like, according to the general part of claim 1.
As is well known, in tanneries there is always the operation of transferring the leathers from one conveyor belt to the next one and the so-called "palletization" operation, which consists of depositing the leathers laid down properly one on top of the other, until an organised pile is formed on a pallet, on a horse or on other similar surfaces.
The drawback that occurs during these operations derives from the fact that the leather, when it is discharged from the conveyor belt on a subsequent belt or on the pallet, is not deposited perfectly flat and laid down properly on the pile, but rather has depressions, creases and ridges, which damage it, making the further picking up and introduction operations thereof in the operating machines problematic.
In particular, the deformation of piled up leathers is substantial in the last depositing portion, when its end portion, detaching from the conveyor belt tends, due to the very nature of the product, to remain raised or, in the worst of cases, to roll up, thus forming depressions in the piles.
In the current state of the art various devices are known suitable for eliminating such a drawback.
The most common device for trying to eliminate such a drawback comprises a fixed accompanying roller that is placed in rotation by the contact with the conveyor belt.
Such an embodiment has the drawback of substantial difficulty of sliding of the leather between the conveyor belt and the accompanying roller, when the leather is rigid or is not laid down properly.
The purpose of the present finding is that of making a device for moving leathers that eliminates such a drawback.
This is obtained with a device that, acting on the end part of the conveyor belt, accompanies the leather for its entire length during the depositing step thereof on the next conveyor belt or on the pile of the pallet or of the horse.
Constructively, the device according to the finding comprises a small sliding band, in a closed loop, held under tension and pulled through at least two rollers, arranged parallel to each other and with the axes arranged in the transversal direction with respect to the advancing direction of the leather.
The two rollers are supported through a frame applied on the bearer structure of the conveyor belt and equipped with means for adjusting the portion of the rollers themselves, in particular to vary its interaxis so as to give the band the correct tension.
Operatively, the device according to the finding is mounted on the conveyor belt so that one of the side strips of the small band is at least tangent, or more advantageously, partially wound on the final curved portion of the conveyor belt itself.
With such an arrangement, the advancing leather always has one of its portions able to slide in the interspace defined between the surface of the conveyor belt and the surface in the small band.
Moreover, with the suitable adjustment of the two rollers, the small sliding band goes over the aforementioned portion of leather slightly compressing it, for which reason it exerts a function on the leather that cooperates with the dragging and, at the same time, avoids the formation on its surface of creases and depressions and prevents the lifting of the edges thereof.
Furthermore, the finding foresees that the roller-carrying frame can be adjusted so that the curved lower portion of the small band, the one wound on the lower roller, is arranged in the immediate vicinity or directly in contact with the leather laid down for which reason, in the return stroke in the conveyor belt, the aforementioned small band, as well as making it easier to deposit, carries out a levelling action on the entire surface of the leather laid down on the pile, flattening out possible ridges or curls, which may have formed along the edges thereof.
The small band is advantageously made from a suitably flexible material, so as to be able to adapt to the curvature generated in the contact zone with the leather, at the end part of the conveyor belt and with antistatic properties, to avoid the sticking of the leather on the small band itself, in particular at the edges, which would thus make it impossible to deposit properly.
The finding shall be better understood through the description of a possible embodiment thereof and of some possible ways of using it, given only as a non-limiting example, with the help of the attached tables of drawings, where:

fig. 1 (Table I) represents a perspective view of the device according to the finding, in a first possible application;
fig. 2 (Table II) represents a schematic front elevated section view of the device according to the finding in use position;
figs. 3 and 4 represent front elevated views, respectively outer and sectioned, of the device according to the finding;
fig. 5 (Table III) represents a perspective view of the device according to the finding, in a second possible form of application;
fig. 6 (Table IV) represents a perspective view of the device according to the finding, in a third possible form of application;

As can be seen in the attached figures, the device according to the finding, wholly indicated with 1, is applied onto the bearer structure 2 of the conveyor belt 3 of the leather 4 which, with the combined advancing movement of the conveyor belt (arrow V1) and back and forth movement of the frame (arrow V2), is deposited onto the pile 5 that forms on the pallet 6 (see fig. 1) or on the horse 7 (see fig. 5) or on a subsequent conveyor belt 8 (see fig. 6).
As can be seen in figs. 2 to 4, the device 1 according to the finding comprises a small band 10, shaped like a closed loop sleeve, which is wound on two rollers 11 and 12 with horizontal and parallel axes.
The inner strip 13 of the small band 10 is placed in contact with a narrow zone 14 of the leather 4, so that the sleeve takes up a variable geometry, which is configured like an arc of circle defined by the radius of curvature of the return cylinder 15 of the conveyor belt 3, for which reason there is a compression force in said zone, which constitutes the characterising element of the finding since, as well as easing the advance of the aforementioned leather, it generates a flattening action on the surface thereof.
The two rollers 11 and 12 are mounted on a frame, wholly indicated with reference numeral 20, consisting of two arms 21, hinged on the pin 22, coaxial with the rotation axis of the aforementioned return cylinder 15.
Each of the two rollers 11 and 12 is mounted on the respective arm 21 through a threaded rod adjustment member 23, by acting on which it is thus possible to vary the interaxis "L" between the two rollers, which thus act as takeup pulleys to adjust the tension of the entire sleeve.
The advancing direction of the small band 10 (arrow V3), matching the advancing direction of the leather 4, can occur by simple dragging, when it is placed in contact with the aforementioned leather, or else through the motorisation of one of the two takeup pulleys 11 or 12.
Finally, as can be seen in particular in figs. 3 and 4, in certain working conditions of the leathers, the device according to the finding is arranged so that the lower roller 12 is positioned close to the depositing surface of the leather on the pile, so that the flattening action of the small band 10 is also applied on the portion of leather 4' that gradually deposits onto the pile itself.
It can thus be seen how through the device according to the finding, consisting of a structure that is easy to build and simple to operate, it is possible to overcome the drawbacks that occur in the moving of leathers, such as the transfer from one conveyor belt to the next, or else the depositing thereof from a conveyor belt onto a pile.
Of course, embodiments that are different from the one described are also possible, without for this reason departing from the scope of the claims, defined hereafter.

Claims

DEVICE TO BE USED DURING THE TRANSFER OF LEATHERS BETWEEN TWO CONVEYOR BELTS AND FOR DEPOSITING THEM ON PALLETS, HORSES AND THE LIKE, suitable for preventing the formation of creases, depressions, ridges and other imperfections, in particular during the end step of deposit, when the final portion of the leather, detaching from the conveyor belt, tends, due to the very nature of the product, to remain raised or, in the worst of conditions, to curl up,
said device being characterised in that
it comprises a small sliding band, in a closed loop, kept under tension through at least two takeup pulleys, arranged parallel to each other and with the axes arranged in the transversal direction with respect to the advancing direction of the leather, which can slide in the interspace defined between the surface of the conveyor belt and the surface of the small band, said small band acting on the entire length of the leather, during the depositing step thereof.
DEVICE, according to claim 1, characterised in that one of the side strips of the small band is at least tangent with the curved final portion of the conveyor belt.
DEVICE, according to claim 1, characterised in that one of the side strips of the small band is partially wound on the curved final portion of the conveyor belt.
DEVICE, according to claim 1 and 2 or 3, characterised in that the two takeup pulleys are supported through a frame equipped with means suitable for adjusting the position of the rollers themselves, in particular to vary its interaxis, so as to give the small band the correct tension.
DEVICE, according to claim 4, characterised in that the support frame of the takeup pulleys is applied onto the support structure of the conveyor belt.
DEVICE, according to one or more of the previous claims, characterised in that the curved lower portion of the small band, the one wound on the lower roller, is arranged in the immediate vicinity of or in direct contact with the leather itself.
DEVICE, according to one or more of the previous claims, characterised in that the small band is made from antistatic material.
DEVICE, according to one or more of the previous claims, applied on the bearer structure (2) of the conveyor belt (3) of the leather (4) which, with the combined advancing movement of the conveyor belt and back and forth movement of the frame, is deposited onto the pile (5) that forms on the pallet (6), on the horse (7) or on a subsequent conveyor belt (8), said device being characterised in that it comprises a small band (10), shaped like a closed loop sleeve, which is wound on two rollers (11, 12) with horizontal and parallel axes and where the inner strip (13) of the small band is placed in contact with a narrow zone (14) of the leather so that the sleeve takes up a variable geometry, configured like an arc of circle, defined by the radius of curvature of the return cylinder (15) of the aforementioned conveyor belt.
DEVICE, according to claim 8, characterised in that the two takeup pulleys (11, 12) are mounted on a frame (20), consisting of two arms (21), hinged on the pin (22), coaxial with the rotation axis of the return cylinder (15) of the conveyor belt (3).
DEVICE, according to claim 9, characterised in that each of the two rollers (11, 12) is mounted on the respective arm (21) through a threaded rod adjustment member (23), so as to be able to vary the interaxis (L) between the two rollers themselves.
DEVICE, according to claim 10, characterised in that the lower roller (12) is positioned close to the depositing surface of the leather on the pile, so that the flattening action of the small band (10) is also applied on the portion of leather (4') that gradually deposits on the pile itself.