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(11) | EP 0 790 010 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Assembly machine for shoes |
| (57) 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. |
[0002] 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.
[0003] 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.
[0004] 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.
[0005] 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.
[0006] 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.
[0007] 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.
[0008] 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.
[0009] 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.
[0010] This has led to an only partial solution of the problems and is a substantially impassable obstacle in view of process automation.
[0011] 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.
[0012] 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.
[0013] Another important object is to provide an assembly machine in which deterioration of the membranes with use is avoided.
[0014] Another object is to eliminate the use of the wedge that is currently required for high-heel or sharp-edged shoes.
[0016] This aim, these objects, and others which will become apparent hereinafter are achieved by a shoe assembly machine, comprising, on a support and resting structure, a dome which supports, at separate elevations, two flexible membranes so as to form, together with said dome, two chambers into which corresponding air ducts lead, said assembly machine being characterized in that said dome is hinged to the structure about an axis which is arranged longitudinally with respect to the position of a shoe to be processed and in that a handling unit for unloading after processing is associated proximate to the part where the heel of said shoe is placed.
[0017] 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;
figures 12 to 14 are schematic views of the unloading step;
figure 15 is a view, taken along a longitudinal plane, of the internal parts of the machine, showing a particular device for fixing a membrane, during a step of the processing of a shoe;
figure 16 is a front view of the device of figure 15 without the covering plate;
figure 17 is a view of a device of figure 15, taken along a longitudinal sectional plane;
figure 18 is a front view of the device with the covering plate;
figure 19 is a perspective view of a portion of the frame of the device of figure 15;
figure 20 is a sectional view, taken along a plane which is parallel to the resting surface of the device of figure 15;
figure 21 is a bottom view of a portion of the frame of the device of figure 15.
[0018] 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.
[0019] The machine is completed by an upper protective housing 14 which has an electrical control panel 15.
[0020] 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.
[0021] The dome 13 has a substantially rectangular plan shape and is adapted to adhere to the resting surface 12 with its lower edge.
[0022] 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.
[0023] 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.
[0024] 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 leyer arm 26 which is rigidly coupled to the dome 13 on the side opposite to the pivot 24.
[0025] 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.
[0026] The position of the shoe 27 is parallel to the pivot 24, which is therefore arranged laterally thereto.
[0027] 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.
[0029] 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.
[0030] 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.
[0031] 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.
[0032] 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.
[0033] 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).
[0034] 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.
[0035] The dome 13 is then moved from a raised position to a lowered position, so that it rests on the surface 12.
[0036] 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.
[0037] 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).
[0038] Once processing has been performed, the dome 13 is opened and the handling unit 36 unloads the shoe 27 (figure 3).
[0039] With particular reference now to figures 15 to 21, a particular device which can be used to fix the membrane 18 is generally designated by the reference numeral 40 and is arranged, in this case, along the base perimeter of the dome 13 of an assembly machine at the edge of said rubber membrane 18.
[0040] A frame 41 for fixing the membrane 18 to said dome is in fact provided along the entire perimetric edge of the dome 13.
[0041] Frame 41 has a fold 42 along its inner perimetric surface, providing the hermetic seal for the membrane 18.
[0042] Device 40 comprises a stub 43 which has a substantially cylindrical structure and is arranged so that it lies longitudinally parallel with respect to the frame 41; stub 43 is accommodated in a seat 44 which is provided for this purpose in the edge of dome 13 to accommodate stub 43 substantially without play.
[0043] A screw 45 engages the stub 43 in a central position, along an axis which lies at right angles to the axis of the longitudinal extension of the stub, by means of a hole which is provided centrally on the stub 43 and is appropriately threaded complementarily.
[0044] Seat 44, formed on an edge portion of said dome 13, has a first cavity, which is shaped like a parallelepiped, has a longitudinal axis which is parallel to the edge of dome 13, and is adapted to accommodate stub 43, and a second cylindrical cavity, which lies along a longitudinal axis of screw 45, is adapted to accommodate the stem of screw 45, and is connected to the first cavity and arranged in a median position with respect thereto.
[0045] Seat 44 can be accessed by means of an opening which is formed on the outer surface and is adapted for the insertion of the stub 43 and of the screw 45 that is engaged therewith.
[0046] A passage channel 46 is formed in the frame 41, can be accessed from the outside, is shaped like a slotted hole, and is located at the second cavity of the seat 44 and coaxially thereto.
[0047] Channel 46 is thus preset to accommodate the stem of screw 45 and, by means of an expansion of the final part of said channel, the head 47 of said screw 45 as well.
[0048] Seat 44 is partially covered by a substantially rectangular plate 48, which is fixed to the outer face of the edge of the dome 13 by screws 49 screwed in corresponding holes 50 formed on the edge of the dome 13.
[0049] Plate 48 forms a rectangular slot in the central region, which is required to ensure the rotation, with corresponding protrusion of the stem from the edge, of screw 45 with respect to the stub-pivot 43.
[0050] Operation of the device is as follows: in order to ensure the tightness of the membrane 18 with respect to the edge of the dome 13 by means of the frame 41, the screws 45 for engaging said frame and said dome one another are tightened firmly.
[0051] When the membrane 18 must be replaced, screws 45 are instead disengaged and rotated with respect to stubs 43, which act as pivots, through the appropriate seats, which act as rotation guides.
[0052] In practice it has been observed that the intended aim and objects of the present invention have been achieved.
[0053] 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.
[0054] 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.
[0055] The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the inventive concept.
[0056] Thus, for example, it is possible to provide for the pivoting of the dome on the opposite side with respect to the one shown and described above.
[0058] In practice, the materials employed, so long as they are compatible with the contingent use, as well as the dimensions, may be any according to requirements.
[0059] 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.
1. A shoe assembly machine, comprising, on a support and resting structure, a dome which
supports, at separate elevations, two flexible membranes so as to form, together with
said dome, two chambers into which corresponding air ducts lead, said assembly machine
being characterized in that said dome is hinged to the structure about an axis which
is arranged longitudinally with respect to the position of a shoe to be processed
and in that a handling unit for unloading after processing is associated proximate
to the part where the heel of said shoe is placed.
2. The shoe assembly machine according to claim 1, characterized in that said dome has
a substantially rectangular plan shape, with said pivoting axis arranged laterally
adjacent to one of the longer sides.
3. The shoe assembly machine according to claim 1, characterized in that said dome is
rigidly coupled to a lever arm which is associated with a pneumatic cylinder for actuating
its rotation.
4. The shoe assembly machine according to claim 1, characterized in that a device for
locking said dome in a lower position for resting on the supporting structure is provided
on the side opposite to the pivoting axis of said dome.
5. The shoe assembly machine according to claim 4, characterized in that said locking
device comprises a lever which is rotatable on a support and is associated with a
pneumatic cylinder, said lever resting, in an upward region, on a wing which protrudes
laterally with respect to said dome.
6. The shoe assembly machine according to claim 1, characterized in that it comprises
a third membrane which is associated with lower edges of said dome and affects the
heel region of the shoe being processed.
7. A device for fixing a membrane to the edge of a dome of a shoe assembly machine by
means of a frame, characterized in that it comprises screws for fixing said frame
to said dome which, by passing through said frame in corresponding through holes,
engage at right angles corresponding retention elements which are associated with
said dome and can only perform rotary motions about their own axis, said through holes
being open laterally to allow the movement of said screws.
8. The fixing device according to claim 7, characterized in that said retention elements
are stubs which are shaped like a solid of revolution the axis whereof is longitudinal
and parallel to said frame, complementarily threaded holes, adapted for engagement
with said screws, being formed on said stubs.
9. The fixing device according to claim 8, characterized in that said stubs are tightly
accommodated in cavities formed along the edge of said dome, said cavities being accessible
from outside.
10. The fixing device according to claim 9, characterized in that said fixing screws comprise
stems which are accommodated in through holes formed along the edge of said dome coaxially
to said complementarily shaped holes of said stubs, said holes being open laterally.
11. The fixing device according to claim 10, characterized in that said cavities for accommodating
said stubs have external protection plates fixed by screws to said dome of said shoe
assembly machine.