A machine for molding and stretching lining, buttress, uppers, and forefoot pieces of footwear

Abstract

 A machine for molding and stretching lining (4), buttress (5), uppers (3), and forefoot (6) pieces of footwear comprises a stretching unit (1) carrying a last (7) adapted to have the assembly to be stretched fitted thereon, which last is provided internally with a heater means and adapted to be driven along a transverse direction to its longitudinal axis; a clamp means (16) operative to clamp the lateral margins of the lining from opposite sides of said last and being driven in the opposite direction from said last of the stretching unit; and a flexible wrapping member (21) operable to lean against said stretching unit to wrap said assembly being stretched around said last.

Description

[0001] This invention relates to a machine for molding and stretching the lining, buttress, uppers and forefoot pieces of footwear.

[0002] It is a known fact that during the manufacturing process of certain shoes it is provided a molding step, i.e. a step wherein the uppers and its associated parts are given a desired shape. Preparatory to this, the inside lining is first cut as appropriate and sewn to the uppers at the location of the uppers top edge. Inserted between the lining and the leather uppers are the buttress and forefoot, usually made of cardboard and acting as reinforcements in the rearand toe regions of a shoe, respectively.

[0003] The above-mentioned parts are made together one another using suitable adhesives, such as a hot-melt adhesive. In that case, the uppers would be preformed, or molded over a suitably heated last to have the aggregated parts adhered on one another.

[0004] Quality shoe uppers are currently stretched over specially provided lasts by hand. While the process can provide creditable results, as a result it entails high production costs.

[0005] Automatic machines are also known which can mold and make the uppers and its associated parts unitary. By automating the shoe manufacturing step, such machines afford significant cost reductions, but often provide less-than-perfect stretching features, so that they are only used to produce shoes of ordinary quality. In fact, their automatic molding sequence is not unlikely to yield creased uppers; additionally, later manual stretching correction is disallowed thereby.

[0006] This invention is directed to solve the above cited problem by providing a machine which can mold and stretch the uppers and its associated parts (lining, buttress, and forefoot) automatically to yield a suitable product for high-quality footwear making.

[0007] Within the above task, it is a further object of the invention to provide a moulding and stretching machine which is simple in design, reliable in operation, and versatile in application.

[0008] These task and object are accomplished, according to the invention, by a machine for molding and stretching lining, buttress, uppers, and forefoot pieces of footwear, which is characterized in that it comprises a stretching unit carrying a last, over which an assembly formed of lining, buttress, uppers, and forefoot is fitted for stretching, said last being provided internally with heater means and adapted to be driven along a transverse direction to its longitudinal axis, clamp means adapted to clamp, from opposite sides of said last, the lateral edges of said lining and to be driven in a direction away from said last on the stretching unit; a flexible wrapping member controllable to lean against said stretching unit and wrap said assembly to be stretched around said last.

[0009] The invention details will become apparent from the following detailed description of a preferred embodiment of this machine for molding and stretching lining, buttress, uppers, and forefoot of footwear, as shown by way of example in the accompanying drawings, wherein:

Figure 1 is a perspective view of this molding and stretching machine;

Figure 2 is a front view of said machine; and

Figure 3 is a perspective view of the uppers and its associated parts as formed on a machine according to the invention:

   With specific reference to the drawing views, generally shown at 1 is the stretching unit of this machine for molding and stretching the assembly of the uppers and its associated footwear parts, hereinafter referred to as the "uppers" for brevity, which assembly is generally denoted by the reference 2.

[0010] Specifically, that assembly includes, as shown in Figure 3, the uppers 3 proper, lining 4, buttress 5, and forefoot 6; the inner lining 4 is sewn to the uppers 3 along the top or hemmed edge of the uppers, to leave a flap 4a for cutting in a later process step.

[0011] The stretching unit 1 is provided with a horizontally elongate core 7 which is shaped to match a designed shape for the uppers 2; more particularly, the core 7 has an oval cross-section shape with a flattened top surface. The core 7 is provided internally with a heater means, preferably in the form of electric resistance heaters.

[0012] The core 7 is supported on an upper bracket 8 extending longitudinally of the core 7, whereby it is carried for sliding movement along a vertical axis in the direction of a machine base 9. A pair of posts 10 rise from the base 9 and have a cross-piece 11 attached to their ends and overlying the stretching unit 1. The cross-piece 11 carries a centrally located cylinder 12, preferably an air-operated one, which drives the core 7 along a vertical direction, the piston rod of said cylinder 12 being made fast with the bracket 8.

[0013] The core 7 has a nosepiece 13 mounted on one end which can be extended along a longitudinal direction relative to the core 7. The nosepiece 13 is carried on rods 14 guided within the core 7 and can be driven by means of a cylinder 15 mounted on the other end of the core 7. The nosepiece 13 has no heater means of its own and is heated conductively from the core 7 that contacts it.

[0014] The bracket 8 also carries, on opposite sides thereof, a pair of clamp members 16 adapted to clamp the lining 4 sidedges; the clamp 16 has respective actuator members 17 operative to control it to close and open. The clamp 16 is supported on a frame 18 which is movable vertically by means of an additional cylinder 19 carried on the bracket 8.

[0015] Arranged beneath the stretching unit 1 is a flexible wrapping member 20 operable to lean against the core 7 underside. This wrapping member 20 consists of a flexible sheet 21 being pivoted to the piston rods of a respective cylinder pair 22 located on either of its opposite sides. The cylinders 22 are mounted for oscillation, about pivot pins 23 carried on respective brackets 24, in a vertical plane transverse to the axis of the core 7.

[0016] At the location of the sheet 21, the top surface of the base 9 is formed with a suitably concave region 9a.

[0017] The machine just described operates as follows. The uppers 2 to be stretched is first inserted bottom up in the gap between the core 7 on the stretching unit 1 and the flexible sheet 21 of the wrapping member 20; the rear portion of the uppers 2 would lie next to the nosepiece 13 which is held against the core 7 at this stage.

[0018] Thereafter, the stretching unit 1 is driven downwards by operating cylinder 12. During a first processing step, the cylinder 12 would be operated under a low pressure for safety reasons. Upon the stretching unit 1 reaching its down or lowered position, the opposite lateral margins of the lining 4 are inserted in the clamp 16 gap, as indicated by the dash line 25 in Figure 2; the clamp 16 is then controlled to close through its actuators 17. Thereafter, the clamp 16 is pulled by its cylinder 19 in the opposite direction to the drive imparted to the core 7, with the core 7 being simultaneously driven by cylinder 12 under a high pressure.

[0019] The cylinders 22 of the wrapping member 20 are then operated to bend the sheet 21 in the direction of the stretching unit 1. The sheet 21 will be wrapped around the uppers 2 on the core 7 to fully stretch it. Before the action of the wrapping member 20 is carried to completion, the clamp 16 is opened to release the lining 4. Finally, the nosepiece 13 is controlled to extend and push onto the rear portion of the uppers 2.

[0020] The above steps are performed under control from a keyboard located in the front portion of the machine. Moreover, such steps are suitably timed.

[0021] During the stretching step, the heat applied to the core 7 causes the various parts associated with the uppers to become thermally adhered through an appropriate hot-melt medium coated thereon.

[0022] Notice in particular that, as against what takes place on conventional machines, the various parts are not locked together throughout the rear region of the shoe, where the nosepiece 13 is arranged to apply its pressure, the uppers 3 and lining 4 being rather left open to the bottom so as to allow the buttress 5 to be accessed and the product trued by hand at some later time.

[0023] In particular, the vertical seam that holds together the two sides of the uppers on the rear can be checked to be true; the height of that seam can be adjusted; and the parallel state of the two sides of the uppers can be checked along the top edge. Subsequently, the stretched and trued uppers can be transferred to conventional automated finishing steps.

[0024] In conclusion, this machine enables the uppers and its associated parts (lining, buttress, and forefoot) to be molded and stretched for a comparatively low cost. Concurrently therewith, the product obtained can be trued manually before the automated finishing step, to thereby yield high-quality footwear.

[0025] For the operation of the invention, the materials used, and the shapes and dimensions, may be any selected ones to suit individual demands.

Claims

1. A machine for molding and stretching lining, buttress, uppers, and forefoot pieces of footwear, characterized in that it comprises a stretching unit (1) carrying a last (7), over which an assembly (2) formed of lining (4), buttress (5), uppers (3), and forefoot (6) is fitted for stretching, said last (7) being provided internally with heater means and adapted to be driven along a transverse direction to its longitudinal axis; clamp means (16) adapted to clamp, from opposite sides of said last (7), the lateral edges of said lining (4) and to be driven in a direction away from said last (7) on the stretching unit (1); and a flexible wrapping member (26) controllable to lean against said stretching unit (1) and wrap said assembly (2) to be stretched around said last (7).

2. A machine according to Claim 1, characterized in that said last in the stretching unit (1) has a nosepiece (13) mounted on one end for an extension movement therefrom, said nosepiece (7) being adapted to be driven along an axial direction of the last (7) to push on the rear portion of said assembly (2) being stretched.

3. A machine according to Claim 1, characterized in that said clamp means (16) is provided with respective actuators (17) effective to drive it to open and close, and is supported on a frame (18) which is operated on a holding bracket (8) for said last (7) on the stretching unit (1).

4. A machine according to Claim 1, characterized in that said wrapping member (20) is a flexible sheet (21) being pivoted, on opposite sides thereof, to the piston rods of a respective pair of cylinder (22) mounted for oscillation in a transverse plane to the axis of said last on the stretching unit (1).

5. A machine for molding and stretching lining (4), buttress (5), uppers (3), and forefoot (6) pieces of footwear, as can be evinced from the specification and the drawings.

Drawing