APPARATUS FOR LOADING AND UNLOADING LEATHERS, SKINS OR SIMILARS, ON OR FROM, AIRCHAIN CONVEYORS

Abstract: An apparatus for loading and unloading leathers, or similars, on, or from, airchain conveyors equipped with horizontal hanging rods, comprises a table, including means for bidirectionally dragging the leather, inclinable, in the whole or partially, and axially extendable until one of its sides is placed in proximity of one hanging rod of said airchain conveyor. The loading operation of the leather on said hanging rod takes place by combining the translatory motion of the leather on said table and the timed back motion on the table itself, or of a portion of it, to the starting position. The unloading operation takes place by just reversing the translatory motion of the leather on the table and by lifting up one side of the table, or of a portion of it, between the flaps of the hanged leather. The timing of back motion of the table, or of a portion of it, in respect of the leather translatory motion on the table, is controlled by means of sensors that detect the leather position on the table. Suitable means and devices are used to enhace the leather adhesion to the table surface and to facilitate the unloading operation through a separation of the leather flaps.

Description: APPARATUS FOR LOADING AND UNLOADING LEATHERS , SKINS OR SIMILARS , ON OR FROM , AIRCHAIN CONVEYORS This invention relates to an apparatus for automatically loading and unloading leathers , skins , or simi lars , on , or from, airchain conveyors equipped with horizontal hanging rods . In the field of leathers processing, the airchain conveyors, generally of monorail type, equipped with specific leathers supporting rods, are commonly used in order to move leathers among working points in the processing line. The hanging rods consist, very simply, of horizontal rods having a free end, and being connected, by the other end, with the airchain conveyor; said rods having a "C" shape, with the lower branch longer than the upper one, in order to achieve a good balance of the whole rod assembly. The hanging reds may also consist of metal rods connected, bv both ends, with the airchain cαnvevor, such kind of rods being used when large size leathers are to be moved. At present, the operations of leathers loading and unloading on, or from, above rods are made manually, by specific workers. This burdens, in a considerable way, the production costs. The primary object of the present invention is to provide an apparatus for automatically loading and unloading leathers, or similars, on or from, airchain conveyors equipped with horizontal hanging rods. According to the broadest aspect of the present invention, there is provided an apparatus for loading and unloading leathers, or similars, on, or from, airchain conveyors equipped with horizontal hanging rods, wherein a table, comprising means for bidirectionally dragging the leathers, s inclinable, m the whole or partially, and is axially extendable until one of its sides is placed in proximity of one hanging rod of said airchain conveyor. The loading operation of leather on said hanging rod takes place by combining the translator;/ motion of the leather on said table and the timed back motion of the table itself, or of a portion of it, to the starting position, whereas the unloading operation takes place by just reversing the translatory motion of the leather on the table and by lifting up one side of the table, or of a portion of it, between the t τ «c flaps of the hanged leather. The timing of back motion of the table, or of a portion of it, in respect of the leather translatory motion on the table, is controlled by means of sensors that detect the leather position on the table. Suitable means and devices are used to enhance the leather adhesion to the table surface and to facilitate the unloading operation through a separation of the leather flaps . The above apparatus allows to carry out in a totally automatic and, consequently, economically favourable way the loading and unloading of leathers, skins, or similars, on or from, airchain conveyors equipped with horizontal hanging rods. For a better understanding of structural characteπcs and operating way of the apparatus of this invention, a preferred embodiment of the same is described in the following, with reference to the accompanying drawings, in which : -Figure 1 is a schematic front view of an apparatus for loading and unloading leathers according to the invention; -Figure 2 is a top view of the apparatus shown in fig.l; -Figure 3 is a side view of an apparatus according to the invention, when used in conjunction with a first kind of hanging rods; -Figure 4 is a side view of an apparatus according to the invention, when used in conjunction with a second kind of hanging rods; -Figure 5 is a schematic front view of the apparatus shown m fig.l, in a particular operating configuration; -Figure 6 is a schematic front view of an apparatus according to the invention m which specific means and devices are shown; -Figure 7 is a detailed schematic view of a portion of the apparatus shewn in fig.6; -Figure 8 is a top view of a device of the apparatus shown in fig.6; -Figure 9, 10 and 11 show schematically three embodiments of an apparatus according to the invention; -Figure 12 shows a detailed portion of a component of an apparatus according to the invention. Referring first to embodiment of fig.l, "10" is an apparatus for loading and unloading leathers, 11, on or from, airchain conveyors, 12, equipped with hσπzzontal hanging rods, 13; these ones being better shown in fig.3 and fig.4. The apparatus 10 includes a table, 14, supported by a fixed structure, 20, of height suitable to allow the regular influx of leathers to said table, 14, from usual belt conveyors, 30, commonly used in the field of leather processing . The leather laying surface of said table, 14, consists of a belt, 21, of rubber, or similar material, having small protrusions, 22, shown in detail in fig.12, useful to increase the leather adhesion to the table surf ce. The belt 21 is cαntmuosly rotating, at constant speed, round two guide rolls, 31, 32, placed in proximity of two opposite sides, 15, 16, of the table 14. The rotation of the belt is assured by the electric motor 23. As we can see in figures 3 and 4 the actuator, 23 X dedicated to the belt rotation, can be placed, either nearby the front side, lb, of table 14, or nearby the opposite side, 15. Above figures 3 and 4 refer to the use of apparatus, 10, in conjunction with two different hanging rods; exactly, in fig.3, the hanging rod, 13 is of the open type, m which only one of its ends is connected to the airchain conveyor, 12; whereas, in fig.4, the hanging rod, 13', is of the type in which both ends are connected to the airchain conveyor. By comparatively examining figures 1 and 5, it can be noted that the upper guide roll, 32, of belt, 21, moves, m the normal working of the apparatus, between the positions numbered with 32a and 32b in the above figures, these positions corresponding, respectively, to the configuration of complete extension of table 14 and to the configuration of complete retraction. In particular, when the apparatus 10 operates as a loader, position 32a, shown in fig.l, represents the position where the transfer of the leather, 11, from the table, 14, to the hanging rod, 13, starts; whereas position, 32b, shown in fig.5, represents the position m which the above transfer is quite completed. The guide roll, 31, of the belt, 21, maintains a fixed position, as referred to the table, 14; so, the extension and retraction of the table upper surface can take place by using two further guide rolls, 33, 34, located m the lower face of said table, 14; said rolls 33, 34, make it possible to recover the remaining part of the belt, 21, during the table, 14, retraction, and, at the same, make it possible to get the belt portion needed to the table extension. One of said rolls, 34, is located in a fixed position, as referred to table 14; the other roll, 33, moves between position 33a of fig.l and position 33b of fig.5, that correspond, respectively, to the positions 32a and 32b of guide roll 32. The guide roll 33, is moved from position 33a to position 33b, and viceversa, through the pneumatic actuator, 35. When the apparatus 10 operates as leather unloader, its front side, 16, is moved vertically, by actuator 26, and is properly guided by the lateral frame columns, 24, 25. The opposite side, 15, of table 14, correspondingly, can be hoπzzαntally moved. At this regard, in fig.6 it is schematically shown, m broken line, a configuration that the table 14 may assume when it is in horizontal position. With 23 and 29 are numbered two sets of proximity sensors that detect the presence of the leathers, 11, nearby on the table 14. Above sensors come m useful to calculate the lenght and the position of leathers on the table, 14, m order to establish perfectly the work timing of table 14, or of a portion of it, 14 X m respect of the leather motion, during the loading operation of the leather on the hanging rod 13. An air-exhauster box, 40, connected with an external vane aspirator, 60, is located internally to the table, 14, at the aim of enhancing the leather adhesion to the upper surface of the table; this feature being useful especially during the unloading operation of leathers, 11, from the airchain conveyor, 12. A device, 41, for separating the flaps of the leather, 11, hanged to the hanging rod, 13, during unloading operation, is located at the top of the lateral frame column 25. As well shown in figures 7 and 8, the above device includes a rod, 42, with a pointed terminal, 43; said rod is connected, at the other end, to a linear pneumatic actuator, 44, capable of moving it, axially, between the flaps of the leather hanged to the hanging rod, 13. The above rod, 42, and its actuator, 44, are constrained to two small platforms, 45, 46, slidable on two guides, 47, 48, placed on the frame column, 25, perpendicularly to the working direction of the actuator, 44. Two further pneumatic cylinders, 49, 50, mounted on two separate brackets, 51, 52, fixed to the column, 25, move both the rod, 42 and the actuator, 44, to the position shown, in broken line, m figures 7 and 8, and viceversa. The above apparatus operates as follows. In the leading operation, leather 11 comes, through the external belt conveyors, 30, to the table 14, and lies on the belt 21, that, as above said, is contmuosly rotating by means of the electric motor 23. At this moment, the guide roll 32, that determines the front end of the table 14, is in position 32b of fig.5. When the front edge of leather 11 passes under the sensor set 28, the above roll 32 is pushed towards the hanging rod 13 in consequence of a specific driving of the pneumatic actuator 35; this one acts directly on guide roll 33, and, indirectly, through a kinematic mechanism, on guide roll 32. The forward motion of front side 16 of table 14 stops when the actuator 35 reaches its end of stroke; the table 14 remains m this extended configuration until the leather 11 has been trasferred, for a half of its lenght, on the hanging rod 13. The very instant in which that happens is found out exactly through a time counting controlled by the sensors sets 23, 29. In fact, at the moment in which the front edge of leather 11 passes under the sensor set 29 it is started the counting of the leather passing time under the sensors; thanks to the constant speed of the leather motion, the above time counting is equivalent to a leather lenght measure . Said time counting is stopped at the moment that the rear edge of leather 11 passes under sensors set 28; owing to the fact that the distance between sensor set 28 and sensor set 29 is a known datum it can be calculated, in a very precise way, the leather lenght and its position on the table 14; in particular, it can be calculated the vey instant in which half the leather is transferred from the table 14 to the hanging rod 13. At said instant the actuator 35 is reversely driven in order to bring the guide roll 32 back to the starting position of the loading cycle. It has to be noted that the co ing back speed of the roll 32 has the same value, but opposite direction, of the translatory motion speed of leather 11 on table 14, so that there is no slipping between the leather and the hanging rod, in this phase. The result is that the transfer of the leather to the hanging rod occurs n a reliable way, that is, with the leather perfectly balanced on the rod. As soon as the transfer operation of the leather on the rod is completed, or m the ending phase of the transfer, the hanging rod, 13, is one step forwarded along the airchain conveyor 12, in order to place the following rod in the loading position; so, a new loading operation can be done according to the above procedure. The above operating procedure of leather loading keeps unchanged as referred to the embodiment of the present invention schematically shown in fig.9. This embodiment is characterized in that the recovery of the remaining part of the belt 21, during the retraction of table 14, is accomplished thanks to the weight force of an appropriate roll, 53; and, furthermore,it is characterized in that the actuator, 35 X causing the extension and retraction of table 14, acts directly on guide roll 32. The same loading procedure is still effective in the embodiment schematically shown in fig.10, where the actuator 35" is controlled according to the same criteria and the same operating cycle above described for the actuator 35. The difference between this embodiment and that of fig.l relies in that, in this case, the movable upper portion 14' of table 14 is phisically distinct from the lower fixed portion of the same table. Exactly, the upper portion 14' comprises a specific belt, 21X rotating driven by an actuator, drawn in light line, phisically distinct from the actuator, 23", dedicated to the rotation of the fixed portion belt, 21. The movable upper portion, 14 X is located in respect of the lower fixed portion of the table 14, in such a way that the leathers can pass simply by gravity from the belt 21 to the belt 21 ' . As regards the unloading of leathers 11 from hanging rods 13, it has to be noted that the starting command of the actuator 26, causing the lifting up of side 16 of the table 14, or of a portion of it, 14X occurs once the information about the proper positioning of rod 13, supporting the leather, reaches the control unit of the apparatus 10, and after that the separation of the leather flaps has been accomplished through the driving of the pneumatic cylinder 44 and , then, of the small cylinders 49, 50 . With the belt 21 rotating in the direction opposite to that of loading operation, the unloading is easily achieved at the moment that said belt, in its upside motion between the leather flaps, comes into contact with one of said flaps and pulls it away from the hanging rod, 13, thanks to the adhesion between belt and leather, expecially enhanced by the air aspirator 40, as schematically shown in fig.b. The coming back of the table 14, or 14', if referred to the embodiment of fig.11, towards its initial position can take place, so, when the front edge of the leather passes under the sensors set 29. About the embodiment of fig.11, we can see that in this case a mobile portion, 14X of the table 14 is joined to a fixed portion of the same table through a hinged joint, 54; the free side of said mobile portion, 14X being lifted and lowered, properly guided by the lateral columns 24, 25. When the table 14, or a portion of it, 14', reaches the cycle starting position, drawn m broken line, the control unit of the apparatus sends to the airchain conveyor control an appropriate signal, allowing the one step forwarding of the hanging rods, in order to carry out, then, a new unloading cycle relating to the following hanged leather. It has to be remarked that the schematic representation of table 14 shown in fig.6 refers to the embodiment of the present invention shown m fig.l as well as to the embodiments of figures 9 and 10. It has to be noted, also, that the lateral guide columns 24, 25 are slightly leaning towards the engaging hanging rod; this produces a small overlapping of the table front side 16 on the hanging rod 13, thus enabling the rod overpassing, by the leather 11, in the loading operation. Still considering the loading operation, it has to be said, according to one aspect of the present invention, that, once the leather 11 reaches the table 14, the front side 16 of the same mav be lifted up with a lifting speed value useful to have the table in its final loading position before that the front edge of the leather 11 come to said front side 16. As regards the coming back speed of the table, it has to be remarked that this speed is well matched with the translator-/ motion speed of the leather 11 on table, 14, m order to assure that, also in this case, there is no slipping between the leather and the hanging rod in the final phase of the loading operation. As we can see, the efficiency of the proposed apparatus. remains unchanged for all the particular embodiments above shown . Obviosly, various modifications will be further envisaged without departure from the scope of the invention. For instance, the dragging means of leathers, or similars, may be different in form; the actuators dedicated to the belt rotation may be placed in different ways; and the same may be for the actuators dedicated to the lifting of the table, or of a portion of it. The sensors revealing the leather presence on table 14 may be different in number and position in respect of the shown embodiments . Obviously, also the fixed supporting structure of the apparatus of the present invention may differ from the proposed ones, schematically shown in the appended drawings . These and other modifications may be carried out, always within the limits of the invention as defined by the following claims.

Claims: L I M S 1- Apparatus (10) for loading and unloading leathers (11), or similars, on, or from, airchain conveyors (12) equipped with horizontal hanging rods (13), said apparatus comprising at least one table (14) including means for bidirectionally dragging the leathers, said table being inclinable, m the whole or partially, and being axially extendible until one of its sides (16) is placed in proximity of one hanging rod of said airchain conveyor (12), the loading operation of the leather (11) on said hanging rod (13) taking place by combining the translatory motion of the leather on said table and the timed back motion of the table (14X or of a portion of it (14'), to the starting position, whereas the unloading operation taking place by just reversing the translatory motion of the leather on the table and by lifting up one side (16) of the table (14), or of a portion of it (14') , between the flaps of the hanged leather. 2- Apparatus flOϊ as claimed in claim 1, wherein said timed back motion of the table ι'14), or of a portion of it (14'), is controlled by using sensors sets f28, 29) detecting the presence of leathers fllϊ, or similars, on said table (14). 3- Apparatus (10) as claimed in claim 1 or 2, wherein said table (14) includes at least one belt C21), of rubber or similar material, having small protrusions, (22), useful to increase the adhesion of the leathers to the belt surface. said belt (21) being contmuosly rotating round at least two guide rolls (31, 32) placed nearby the entry and the exit sides of the leathers on said table. 4- Apparatus (10) as claimed in claim 3, wherein said belt (21) is contmuosly rotating round two further guide rolls (33, 34), one of said rolls (34) being m a fixed position in respect of said table (14), the other one of said rolls (33) being shiftable between two positions (33a, 33b) corresponding, respectively, to a complete extended con iguration and to a complete retracted configuration of said table (14) . 5- Apparatus (10) as claimed in claim 1 or 4, wherein one side (16) of said table (14) is lifted and lowered, the motion of said side (16) being guided by two lateral columns (24, 25) slightly leaning towards the engaging hanging rod (13), such that the table side (16) may overlap said hanging rod (13) in the loading phase. 6- Apparatus (10) as claimed in claim 5, wherem said table (14) comprises a fixed portion and a mobile portion (14') joined by a hinged joint (54), the free side (16) of said mobile portion (14') being lifted and lowered and being guided by said two lateral columns (24, 25). 7- Apparatus (10) as claimed in claim 1 or 3, wherein said belt (21 'i is pulled down by the weight force of a roll ( S3 ) located in the lower face of said table (14j, so as to manage the lenght variations of the upper surface of the belt, said variations being due to the extension and retraction motion of a portion (14') of said table (14). 8- Apparatus (10) as claimed m claim 1 or 2, wherem said table (14) comprises two belts (21, 21') contmuosly rotating by means of two separate actuators, one of said belts (21) being in a fixed position relative to said table, the other one (21') being movable between two positions corresponding respectively to the complete extended configuration and to the complete retracted configuration of said table (14). 9- Apparatus (10) as claimed in any preceding claim, wherem said timed back motion of said table (14), or of a portion of it (14'), in the loading operation, starts at the very istant m which half the leather has been transferred from said table (14) to said hanging rod (13). 10- Apparatus (101 as claimed in anv preceding claim, said apparatus comprising means (41) for separating the flaps of the leather (11) hanged to the hanging rod (13) during the unloading operation. 11- Apparatus (10) & claimed in claim 10, wherein said means (41) includes a rod (42) with a pointed terminal (43ϊ, said rod being connected, at the other end, to a linear pneumatic actuator (44) capable of moving it, axially, between the flaps of the leather hanged to the hanging rod (13ϊ, said rod (42) and its actuator (44) being constrained to two small platforms (45, 46) slidable on two guides (47, 48) located on a frame column (25) perpendicularly to the working direction of said actuator (44), two further pneumatic cylinders (49, 50) being mounted on two separate brackets (51, 52) fixed to said column (25) so as to separate the leather flaps by moving both the rod (42) and the actuator (44) along said guides (47, 48) after that said rod (42) has been inserted between said leather flaps. 12- Apparatus (10) as claimed in any preceding claim, wherein air-aspirators (40) are located inside said table (14), in proximity of its upper surface, so as to enhance the adhesion of the leathers to said table, in particular, during the leather unloading operation.

Inventors: SANI ANTONELLO, SANI, ANTONELLO
Applicants: SANI ANTONELLO, THEMA DI SANI ANTONELLO & C S, SANI, ANTONELLO, THEMA DI SANI ANTONELLO & C., S.N.C.
Application year: 1998
Main classification: B65G47
IPC codes: B65G47, C14B1