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(11) | EP 0 676 153 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Welt-laster |
| (57) A machine for lasting the welt of a footwear upper assembly (1) that includes a last
(2) having an insole located at the last bottom, with a rib (4) secured to the insole
(3) near the insole periphery and extending downward and away from the lower surface
of the insole (3), the rib (4) being displaced an incremental distance from said periphery
at the toe end of the assembly to form a corner region between the surface of the
insole (3) at the corner region and the rib (4) to receive an adhesive. The machine
includes an anvil (6) to receive the bottom surface of the insole (3) and operable
to provide a wiping plane and, also, support for the rib (4) during wiping; pincers
(8) positioned to receive the cement margin. An anvil drive serves to press the footwear
upper assembly (1) upward to stretch the upper about the last (2) against a downward
force exerted by the pincers (8). Nozzles (30A,30B) are positioned to apply adhesive
into the corner region; and wipers are positioned to wipe the cement margin at the
corner region. |
Background of the Invention
[0002] Attention is called to United States Letters Patent 4829932 (Bennett); 4530124 (Sommer); 4553281 (Vornberger); and 4654914 (Leeper) -- all incorporated by reference herein.
[0003] The Bennett patent discloses a mechanical scheme for directing nozzles of the general type herein disclosed along paths of the insole while applying adhesive from the nozzles onto the outside surface of the insole near the periphery (or edge) of the insole. That technique has now been followed by using computers which control servomotors and stepper motors as drivers and controllers. In the latter case, the path taken by nozzles in the prior art, is determined by tracing the desired path and simultaneously digitizing that path. This technique has been applied to prior-art toe lasters, heel lasters, and the like. Welt lasters, otherwise like the laster disclosed herein and using computer technology, have employed extruders to apply adhesive into the corner between an outwardly extending rib of the upper and the cement margin thereof, but they require frequent changes of extruder.
[0004] Accordingly, it is an object of the present invention to provide a welt laster in which the extruder of earlier machines is replaced by a structure which does not require frequent replacement of the adhesive applicator because of its size, style and/or shape.
Brief Description of the Drawings
[0006]
Fig. 1 is a front view, partly cut away, showing parts of a welt-lasting machine of the present invention with a footwear upper assembly in its lasting position.
Fig. 2 is a plan view showing parts of the machine in Fig. 1.
Fig. 3 is a diagrammatic representation showing parts of the machine in Fig. 1.
Fig. 4 is a front view showing parts of the machine in Fig. 1.
Detailed Description of the Invention
[0007] Turning now to the figures, those portions of a welt-laster or welt-lasting machine necessary to understand the present invention are shown at 101 in Fig. 3 and elsewhere. The machine 101 is operable to last a footwear upper assembly 1 that includes a last 2 having an upper 19 draped about the last and an insole 3 located at the last bottom with a welt rib 4 secured to the insole and extending outward and away from the insole, and generally orthogonal to the plane of the insole. The welt rib 4 is displaced inwardly an incremental distance d from the insole periphery --typically between the toe and the ball of the footwear-- to provide a surface 5 which, together with the welt rib 4, form a corner region or angle 50 between the surface 5 of the insole and the welt rib 4 into which an adhesive is applied during lasting. The machine 101 includes an anvil 6 to receive the lower surface of the insole 3. The anvil 6 is operable to provide a wiping plane in the X-Y plane of an XYZ-coordinate system in Fig. 2. The anvil 6 also supplies support for the rib 4 during wiping of the cement margin 9 by wipers 7 in Fig. 4, as noted below. Pincers 8 are positioned to receive the cement margin labeled 9 (Fig. 4) of the footwear upper assembly 1 at which time an anvil drive post 10 is driven upward in Fig. 1 from a lowered position by an anvil drive 11 (e.g., air) against a downward force exerted by the pincers 8 to stretch the upper 19 about the last 2. Conceptually, the anvil 6 can be initially postioned at the vertical position shown in Fig. 1, thus establishing the wiping plane, and downward force can be exerted by the pincers 8 in typical pincer operation. (It should be noted that the terms "upward", "downward" and like terms herein are used for purposes of simplifying this description, but the whole machine can be moved to another orientation, at least conceptually.) Nozzles 30A and 30B are positioned to apply adhesive into the corner region (or angle) 50, it being understood that 50 designates the region (or any part thereof) between the rib 4 and the surface 5. (Typically the rib 4 has a height, Z-direction, of about six millimeters and the surface 5 has a width of four or five millimeters). The welt rib 4 typically extends from one ball region of the footwear to the toe and thence to the other ball region.
[0008] The nozzles 30A and 30B in Figs. 3 and 4 are composite structures which are pressed upward toward the surface 5 by a piston 51 (e.g., air) which acts as a fluid spring to move the upper part 20 in Fig. 3 to slide over the lower part 21 to force the nozzle 30A into the region of the corner 50. (See the Bennett patent, for example.) The nozzle 30A (or 30B) can bind in the corner 50 but is restrained from doing so by the positioning compliance system labeled 60 in Fig. 3, which includes a servomotor 61 which drives a leadscrew and nut 62 to move the nozzle assembly in the X-direction. (A further system like the system 60, moves the nozzle 30B in the X-direction.) Simultaneously, the nozzles 30A and 30B are moved synchronously in the Y-direction by a servo system 65 which is similar to the system 60.) Feedback signals are generated by an encoder 63 to a servocontroller 64 controlled by software 66 in the system 60.
an anvil to receive the bottom surface of the insole and operable to provide a wiping plane and support for the rib during wiping;
an anvil drive mechanism;
pincers positioned to receive the cement margin, the anvil drive mechanism being adapted to press the footwear upper assembly upward to stretch the upper about the last against a downward force exerted by the pincers;
pen-type nozzles positioned for movement along the cement margin and parallel thereto to apply adhesive into said corner region; and
wipers positioned to wipe the cement margin at said corner region.
providing an anvil to receive the bottom surface of the insole and operable to provide a wiping plane and support for the rib during wiping;
providing pincers positioned to receive the cement margin;
presenting the footwear upper assembly, bottom down, to the anvil, and presenting the margin directed downwardly to the pincers, pressing the anvil upward pressing the footwear upper assembly upward to stretch the upper about the last against a downward force exerted by the pincers;
positioning and moving pen-type nozzles along the cement margin and parallel thereto to apply adhesive into said corner region and applying the adhesive into the corner region; and
wiping the cement margin at said corner region to secure the cement margin into said corner region.
an anvil to receive the bottom surface of the insole and operable to provide a wiping plane and support for the rib during wiping;
pincers positioned to receive the cement margin and operable, in combination with the anvil to stretch the footwear upper about the last against a stretching force exerted by the pincers;
at least one pen-type nozzle positioned for movement along the cement margin and parallel thereto to apply adhesive into said corner region; and
wipers positioned to wipe the cement margin at said corner region.
an anvil to receive the bottom surface of the insole and operable to provide a wiping plane and support for the welt rib during wiping;
pincers positioned to receive the cement margin, the anvil being adapted to press the footwear upper assembly upward to stretch the upper about the last against a downward force exerted by the pincers;
pen-type nozzles positioned for movement along the cement margin and parallel thereto to apply adhesive into said corner region; and
wipers positioned to wipe the cement margin into said corner region.
an anvil to receive the bottom surface of the insole and operable to provide a wiping plane and support for the welt rib during wiping;
pincers positioned to receive the cement margin, the anvil being adapted to press the footwear upper assembly upward to stretch the upper about the last against a downward force exerted by the pincers;
at least one pen-type nozzle positioned for movement along the cement margin and parallel thereto to apply adhesive onto a portion of said rib; and
wipers positioned to wipe the cement margin.