Assembly machine for shoes

Abstract: A shoe assembly machine, comprising, on a support and resting structure (11,12), a dome (13) which supports, at separate elevations, two flexible membranes (18,19) so as to form, together with said dome (13), two chambers (20,21) into which corresponding air ducts (22,23) lead. The dome (13) is hinged to the structure (11,12) about an axis which is arranged longitudinally with respect to the position of a shoe (27) to be processed and a handling unit (36) for unloading after processing is associated proximate to the part where the heel of the shoe (27) is placed.

Description: The present invention relates to an assembly machine for shoes. Devices commonly known as assembly machines in the shoe manufacturing field are known; in practice, they are adapted to assemble together a pre-glued sole and upper, providing perfect assembly every time. These machines substantially comprise, on a support and resting structure, a dome which supports, at separate vertical levels, two rubber membranes which form two chambers together with said dome; corresponding ducts for air supply and aspiration lead into said two chambers. The dome is rigidly coupled to the structure with a hinge-like coupling and is rotatable about a horizontal axis which is perpendicular to the position assumed by the shoe to be processed. During operation, an operator places himself in front of the machine and loads the shoe on the supporting surface, this operation being possible through the opening of the dome, the rotation axis whereof is at the rear; then the machine automatically performs the assembly operation, the dome is reopened, and the same operator performs unloading. An example of such a machine is disclosed for example in prior art document GB-2,151,904. Although the commercial introduction of machines such as the one described above has been a considerable technological step forward with respect to conventional assembly systems, nonetheless it has not been free from drawbacks, which have become evident particularly due to the change in the demands of users, who are increasingly orientated towards reducing human intervention in the production cycle. Although the operating principle is currently ideal, it has accordingly been found that the structure of the machine is not particularly adapted for use in automatic or semiautomatic processing lines, since loading and unloading are performed at the same position. Other drawbacks have been observed in particular for shoes with soles having a high heel with sharp edges, which rapidly deteriorate the lowermost membrane, i.e., the membrane that rests directly on the shoe during processing. An attempt has been made to obviate these drawbacks by manually inserting an appropriate wedge, adapted to level the surface to be pressed, avoiding abnormal stretching of the pressing membranes and their consequent deterioration. This has led to an only partial solution of the problems and is a substantially impassable obstacle in view of process automation. A principal aim of the present invention is to provide an assembly machine for shoes which has a structure that allows to reduce processing times. Within the scope of this aim, a consequent primary object is to provide an assembly machine the structure whereof allows to include it in semiautomatic or automatic lines for the processing of shoes. Another important object is to provide an assembly machine in which deterioration of the membranes with use is avoided. Another object is to eliminate the use of the wedge that is currently required for high-heel or sharp-edged shoes. A further object is to provide an assembly machine that is commercially competitive. This aim, these objects, and others which will become apparent hereinafter are achieved by a shoe assembly machine as defined in claim 1. Further characteristics and advantages of the invention will become apparent from the following detailed description of an embodiment thereof, illustrated only by way of non-limitative example in the accompanying drawings, wherein: figure 1 is a front perspective view of the machine; figure 2 is a rear perspective view of the machine; figure 3 is a schematic view of the step for unloading the shoes from two machines, one for the right shoe and one for the left shoe, onto a conveyor belt; figure 4 is a sectional view, showing the internal parts of the machine before work; figure 5 is a view of the internal parts of figure 4 during work; figures 6 and 7 are longitudinal sectional views of the internal parts of the machine in successive steps of the processing of a shoe with a sharp-edged heel; figure 8 is a transverse sectional view of the internal parts of the machine during the processing of a shoe with a sharp-edged heel; figure 9 is a bottom view of the dome included in the machine; figures 10 and 11 are longitudinal sectional views of the internal parts of the machine in successive steps of the processing of a shoe with a rounded heel; and figures 12 to 14 are schematic views of the unloading step. With reference to the above figures, an assembly machine is generally designated by the reference numeral 10 and comprises a supporting structure 11 whereon a resting surface 12 is formed in an upward region; a dome 13 acts on said surface, as better described hereinafter. The machine is completed by an upper protective housing 14 which has an electrical control panel 15. Dome 13 is constituted by a box-like structure which is open in a downward region and is divided into two parts, designated by the reference numerals 16 and 17 respectively, to which the edges of two rubber membranes 18 and 19 are fixed hermetically at two different elevations, the first membrane being arranged at a lower level. The dome 13 has a substantially rectangular plan shape and is adapted to adhere to the resting surface 12 with its lower edge. The membranes 18 and 19 form, together with the dome 13, two chambers 20 and 21 into which corresponding air ducts 22 and 23 lead. As shown in the figures, the dome 13 is rigidly coupled to the structure of the machine 10 so as to rise from the resting surface 12, since it is hinged by means of a pivot 24 arranged laterally and longitudinally thereto. Rotation occurs by means of a pneumatic cylinder, of which the figures show only the stem, designated by the reference numeral 25; said cylinder is pivoted to a lever arm 26 which is rigidly coupled to the dome 13 on the side opposite to the pivot 24. The shoe being processed, designated by the reference numeral 27, is supported by an upper-holding last 28, which is arranged at an opening of the resting surface 12. The position of the shoe 27 is parallel to the pivot 24, which is therefore arranged laterally thereto. A device 30 for locking the dome 13 is arranged on the opposite side of the pivot 24, relative to the shoe 27, and is constituted by a support 31 to which a lever 32 is articulated; the lever is associated, by means of a connecting arm 33, with a pneumatic cylinder, only the stem 34 whereof is visible in the figures. The lever 32 acts on a rectangular lip 35 which protrudes from the dome 13. A per se known clamp-type handling unit 36 is arranged in the region of the machine 10 that corresponds to the position of the heel of the shoe 27 and is rotatable about a horizontal axis which lies transversely to the shoe 27. Handling unit 36 is adapted to unload the shoe 27 after processing, as shown more clearly in figure 3, arranging it for example on a conveyor belt 37 of a cooling unit, not shown in the figures. It should also be noted that a third membrane 38, which affects only the rear part of the shoe at the heel, is rigidly coupled, with its ends, between the lateral edges of the dome 13, as shown in particular in figures 6 and 7. This third membrane 38 has a purely protective function for the other membranes, since it is the one that protects the others from deterioration in case of shoes having sharp-edged heels. As regards operation, the operator places himself in front of the machine and places the shoe 27 on its support inside the region where the dome 13 acts (figure 4). During this operation, air is drawn from the air ducts 22 and 23 so as to form a negative pressure in the chambers 20 and 21, so that the membranes 18 and 19 cause no hindrance. The dome 13 is then moved from a raised position to a lowered position, so that it rests on the surface 12. The lever 32 that locks the dome 13 is then closed and the lowermost chamber 20 is pressurized by feeding air into the duct 22, so that the membrane 18 fully adheres to the shoe, wrapping around the sole 27a and the upper 27b. The next operation is the feeding of air to the chamber 21 through the duct 23 to compress the sole 27a on the upper 27b (figure 5). Once processing has been performed, the dome 13 is opened and the handling unit 36 unloads the shoe 27 (figure 3). In practice it has been observed that the intended aim and objects of the present invention have been achieved. The arrangement of the rotation axis in the dome 13 laterally with respect to shoe 27 has in fact allowed to free up the operating possibilities in front of said shoe 27 and behind it and has therefore allowed front loading and rear unloading, said unloading being performed automatically by means of the handling unit 36. The addition of the third membrane 38 has allowed to extend the life of the membranes 18 and 19 before they need to be replaced and avoids the need to resort to the wedge mentioned in the introduction. In a slightly different embodiment of the invention, it is possible, for example, to provide for the pivoting of the dome on the opposite side with respect to the one shown and described above. Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims: A shoe assembly machine, comprising, on a support structure (11, 12), a dome (13) which supports, at separate elevations, two flexible membranes (18,19) so as to form, together with said dome, two chambers (20, 21) into which corresponding air ducts lead (22, 23), characterized in that said dome (13) is hinged to the structure (11, 12) about an axis which is arranged longitudinally with respect to the position of a shoe (27) to be processed and in that a handling unit (36) for unloading after processing is associated proximate to the part where the heel of said shoe is placed, a third membrane being (38) supported by the edges of said dome (13) and affecting the heel region of the shoe being processed. The shoe assembly machine according to claim 1, characterized in that said dome (13) has a substantially rectangular plan shape, with said pivoting axis arranged laterally adjacent to one of the longer sides. The shoe assembly machine according to claim 1, characterized in that said dome (13) is rigidly coupled to a lever arm (26) which is associated with a pneumatic cylinder (25) for actuating its rotation. The shoe assembly machine according to claim 1, characterized in that a device (30) for locking said dome (13) in a lower position for resting on the supporting structure (11, 12) is provided on the side opposite to the pivoting axis of said dome. The shoe assembly machine according to claim 4, characterized in that said locking device (30) comprises a lever (32) which is rotatable on a support (31) and is associated with a pneumatic cylinder (25), said lever resting on a rectangular lip (35) which protrudes laterally with respect to said dome (13).

Inventors: PAOLUCCI ENZO, PAOLUCCI, ENZO
Applicants: IRON FOX SRL, IRON FOX S.R.L.
Application year: 1996
Main classification: A43D25
IPC codes: A43D25