The present invention relates to a machine for manufacturing shoes and in particular to a machine for pulling over and lasting an upper on a corresponding shoe form.

As is known, in the manufacture of shoes, the upper is glued to the insole. In order to achieve this, the upper is fitted and stretched over a form, to the bottom of which an insole has been applied beforehand. Then, after spreading glue around the contour of the insole, the edge portions of the upper are folded back and pressed against the insole.

In accordance with the known art, the abovementioned operations are performed automatically using pulling-over machines. These machines comprise a support element for positioning of the shoe form thereon, pushing devices acting on the form in order to keep it in pressing contact against the support, a plurality of grippers for tensioning the upper, which are arranged around the support element, means for supplying glue along the contour of the insole, means for folding back the edges of the upper towards the underside of the form and means for pressing, from underneath, the edges of the upper folded against the insole.

Machines of this type are known, for example, from the patents US-A 357691 and EP 0,118,243 B2.

The use of machines which are able to perform the abovementioned operations automatically has proved to be advantageous both from the point of view of the high production volumes which these machines are able to achieve and owing to the uniform quality which these machines are able to ensure for the products obtained.

The requirement which these machines must satisfy is that of managing to be adapted to the different dimensions and shapes of the existing insoles. In this connection it must be considered that, in the case of insoles of the same size, there may be models with different shapes and fits (for example narrow or wide fit).

In order to achieve good gluing of the upper to the insole, it is necessary for the glue to be properly distributed around the contour of the insole. Therefore, it is obvious that, when there is a variation in the shape of the insole, the glue supplying means must be able to supply the glue at the required points.

The need is therefore that of managing to provide glue supplying means which are able to be adapted to the different configurations of the existing inner soles.

It must also be considered that supplying of the glue must be limited to only the portions of the insole which are intended to be glued to the upper, namely along the contour of the insole. In fact, the presence of glue outside of these portions is undesirable during the successive processing operations which the upper must undergo.

In machines of the known art, the glue supplying means mainly consist of a supply plate provided with a plurality of nozzles arranged so as to be substantially positioned along the contour of the insole.

However, these machines have the drawback that they cannot be adapted to insoles which have very different shapes and dimensions, except by means of replacement of the supply plate. Basically, these machines are provided with a plurality of interchangeable glue supply plates from among which it is necessary to choose the plate which is most suitable for the shape of the insole to be glued.

In the patent EP 0,118,243 B2 the glue supplying means comprise a supply plate for supplying the glue in the region of the front portion of the insole and a movable nozzle for supplying the glue along the remaining part of the contour of the insole.

In the patent it is also specified that the supply plate extends along the longitudinal axis of the insole over a distance of only 50 mm measured from the toe of the insole, so as to be suitable for most insoles.

This conclusion is based on the consideration that the front portion of the insole, namely the toe, remains substantially unchanged when there is change in the shape and dimension of the insole.

However, this is not exactly true. In order to illustrate this point, one need merely mention that there are shoes with square toes as opposed to shoes with rounded toes.

The solution proposed in the patent EP 0,118,243 B2, therefore, does not overcome the above mentioned drawback, but only partially solves the problem. In other words, in order to be able to process insoles which are differently shaped, it is in any case necessary to use different types of interchangeable plates.

The same limitation is present in US 3,422,474.

To overcome this limitation EP 0,338,725 and EP 0,138,474 disclose an adhesive applicator mechanism, for supplying the glue in the region of the front portion of the insole, comprising a plurality of adhesive supplying elements articulated to each other so as to enable the configuration of the adhesive applying surface to be varied, according to the needs, by varying the relationship between the elements.

In order to vary the relative position of the elements, adjustment threaded rods and complicated actuation devices, permanently coupled to the elements, are provided, which cannot be reconciled at all or easily reconciled with the requirement of leaving free space, without any encumbrance, for the movable nozzle or nozzles supplying the glue along the remaining part of the contour of the insole.

In fact, the relative position of the elements not only is adjusted by the actuation devices, but is also held by the actuation devices, missing which, the relative position is subjected to possible changes, particularly in an operative environment with mechanical movements and consequent shocks and vibrations.

A secure clamping in position of the elements cannot be provided by position adjusting threaded rods, as disclosed in D2.

The problem underlying the present invention is that of devising a machine for manufacturing shoes which has structural and functional characteristics such that it is able to satisfy the above mentioned requirements and at the same time overcome the drawbacks associated with machines of the known art in simple way. This problem is solved by a machine for manufacturing shoes in accordance with Claim 1.

Further characteristic features and advantages of the machine according to the present invention will emerge from the description below of a preferred example of embodiment thereof provided by way of a non-limiting example with reference to the accompanying figures, in which:

• Figure 1 shows a perspective schematic view of a machine according to the invention;
• Figure 2 shows a perspective view, on a larger scale, of a detail of the machine according to Figure 1;
• Figure 3 shows a perspective and exploded view of a detail according to Figure 2;
• Figures 4 and 5 show a schematic plan view of the detail according to Figure 3 in two different operating configurations;
• Figures 6, 7 and 8 show schematic views of a detail of the machine according to Figure 1 during different stages of the machine operating cycle; and
• Figure 9 shows a perspective view of a shoe form with upper and insole on which the position of the glue applied with the machine according to Figure 1 is shown.

With reference to the accompanying figures, 1 denotes in its entirety a machine for pulling over and lasting an upper 21 on a shoe form 2. An insole 23 is applied onto the underside 15 of the form 2.

The machine 1 comprises a supporting frame 3 to which positioning means 5 intended to support the form 2 in the region of the toe 6 thereof are fixed.

In the example, the positioning means 5 consist of a support element 4 with a flat triangular surface which extends over a small area and against which the form 2 is intended to be rested.

The support element 4 is inclined so that the line Z perpendicular to its flat triangular surface substantially coincides with the line of vision of an operator who observes the surface 5 itself, standing in front of the machine 1 (at the point indicated by "O" in Figure 1).

The machine 1 comprises an upper pushing device 7, two side pushing devices, both indicated by 8, and a rear pushing device 9. These pushing devices are intended to engage respectively with the back 10, with the sides 11 and with the heel 12 of the form 2, so as to keep the form itself in pressing contact against the triangular surface of the support element 4, in an operative working position (Figures 6 to 8).

A plurality of grippers, which are all indicated by 13, are arranged around the support element 4 so as to face the contour of the toe 6 of the shoe form 2. In a manner conventional per se, the grippers 13 are actuated so as to open and close and are individually displaced according to needs so as to achieve the desired tensioning of the upper 21 on the shoe form 2.

The machine 1 also comprises means which are indicated overall by 14, for folding back the edges of the upper 21 towards the underside 15 of the shoe form 2, after opening of the grippers 13, as well as means, indicated in their entirety by 16, for pressing from underneath the folded-back edges of the upper 21 against the insole 23 along its contour provided with glue 24.

In the example shown, the means 14 for folding back the edges of the upper 21 comprise two curved plates 17 reproducing the profile of the contour of the toe 6 of the shoe form 2 and movable towards the form itself. The means 16 comprise a plurality of rod-shaped elements 18 which are movable (in a transverse direction Y-Y) towards the form 2 so as to engage with it, from underneath, with a predetermined elastic force.

The machine 1 comprises means for supplying the glue along the contour 27 of the insole 23 associated with the underside 15.

These means comprise a supply plate 19 positioned in the vicinity of the support element 4 and two nozzles 23 for supplying the glue, which are movable so as to be able to follow the contour 27 of the insole 23.

The supply plate 19, which according to a preferred example of embodiment is in the form of a horseshoe (Fig. 5), is positioned around the support element 4 and comprises a plurality of fixed supply nozzles indicated by 20 in the figure.

By means of actuating means conventional per se and not shown in the Figures, such as for example hydraulic actuators, the plate 19 is movable in the direction of the axis Z-Z indicated in Figure 1 from a rest position at a distance from the form 2 (Fig. 6) to an active position (Figs. 7 and 8) where it engages from underneath with the shoe form 2 (more precisely with the insole 23 applied to the underside 15) so as to distribute the glue 24 along the contour 27 of the insole 23 by means of the supply nozzles 20.

In the light of what has been described above, it is-obvious that the plate 19 allows the glue 24 to be supplied along the contour 27 of the front portion of the insole 23, namely in the region of the toe 6 of the shoe form 2.

The supply plate 19 comprises a plurality of segments 19a, 19b which are arranged one after another and connected together in chain by means of hinged connections. The plate 19 is therefore articulated so as to be able to adapt its shape to the shape of the contour 27 of the insole 23. In the example shown in the Figure, the plate 13 comprises four segments 19a,19b which are arranged one after another, in chain, so as to form a horseshoe and are connected by means of pins 26 which are three in number (26A,26b,26c)in the example. For this purpose, the ends of the segment 19a,19b terminate in an eyelet intended to be engaged by the pins 26.

According to the invention, the supply plate 19 is associated with an underlying support plate 28 so as to be able to be hingeably connected wit respect thereto.

The intermediate pin 26A in the chain is steadily positioned on the support plate 28 along the axis of symmetry (or centre line) X-X of the support plate 28, namely at the toe end of the shoe form 2, while the other two pins 26B,26C, moveable relative to the support plate 28, are positioned so as to be located on opposite sides with respect to the above mentioned axis of symmetry.

By hingeably adjusting the segments 19a of the plate 19 about the hinging pin 26A and the segments 19b about the hinging pins 26B and 26C it is therefore possible to adapt the shape of the plate 19 to that of the different insoles 23. With reference to Figures 4 and 5, the plate 19 is shown in the narrow and widened configurations, respectively.

The supply plate 19 and the support plate 28, besides being connected by the pin 26A, are connected by means of two fixing elements 31 which allow the segments 19b of the supply plate 19, remote from pin 26A to be steadily fixed and locked in the desired position with respect to the support plate 28. Preferably, the fixing elements 31 comprise screws 29, the shanks of which are inserted into respective eyelets 30 in the segments 19b of the plate 19.

The size of the head of the screws 29 is greater than the size of the eyelets 30. The shanks of the screws 29 are also inserted into respective elongated eyelets or slots 32 of the support plate 28. The end portions of the screws 29 emerging from the eyelets 32 are provided with a fixing nut 25 (Fig.3). Until the screws 29 are fully tightened, the screws themselves are able to move in the eyelets 32 and consequently it is possible to vary the position of the segments 19a, 19b with respect to the support plate 28.

On the other hand, when the screws 29 are tightened, the heads thereof lock the segments 19b against the support plate 29, preventing any further displacement of both segments 19a and 19b.

The above mentioned actuating means which move the plate 19 from the rest position at a distance from the form 2 (Fig. 6) to the active position (Figs. 6 and 7) act on the supply plate 19 by means of the support plate 28.

The glue supplying means of the machine 1 further comprise two nozzles for supplying the glue, indicated by 22. The nozzles 22 are movable, namely are supported by the frame 3 of the machine 1 so as to be able to follow the portion of the contour 27 of the insole 23 which is not affected by the supply plate 19. In particular, with the nozzles 22 it is possible to follow and therefore supply the glue 24 along the opposite sides of the insole 23.

The machine 1 comprises actuating means which are known per se and not shown in the Figures, for example hydraulic actuators, which allow the nozzles 22 to be actuated so that they move along the contour 27 of the insole starting from the plate 19, namely in the zone which is not affected by the supply plate 19. The machine 1 comprises operating and control means, not shown in the Figures, for managing operation of the actuating means. In particular, during each operating cycle of the machine 1, these operating and control means allow the nozzles 22 to be positioned along the contour 27 of the insole 23 and behind the plate 19, also when there is a variation in the shape of the plate 19. Therefore, the abovementioned operating and control means allow the movement and the displacements of the nozzles 22 to be varied according to the type of insole 23. For this purpose, the operating and control means comprise a memory, such as for example an EEPROM, in which it is possible to store different programs for movement of the nozzles 22.

Preferably, the nozzles 22 terminate in a roller which allows distribution of the glue 24 supplied along the contour 27 of the insole 23.

Electric resistances, which allow the glue to be heated so as to render it more fluid, are associated with the supply plate 19 and the nozzles 22.

The nozzles of the supply plate 19 and the movable nozzles 22 are in fluid communication with a glue storage tank (not shown in the figures).

During operation of the machine 1, the shoe form 2 is placed against the support element 4. Then the pushing devices 7, 8 and 9 fix the form 2 in its working position (Figures 6, 7 and 8). Tensioning of the upper 21 is performed on the form 2 by means of the grippers 13.

At this point, displacement of the supply plate 19 is effected from the rest position (Fig. 6) to the active position (Figs. 7 and 8) where the glue is supplied via the nozzles 20. The glue 24 is therefore applied and distributed along the front portion of the contour 27 of the insole 23. Once supplying of the glue 24 has been performed, the supply plate 19 is brought back into the rest position.

At the same time, the nozzles 22 are actuated so that they come into contact with the contour 27 of the insole 23, in the vicinity of the supply plate 19 (Fig. 7). Then the nozzles 22 are actuated so that they follow the contour 27 of the insole 22 (until they reach the position illustrated in Figure 8) so as to supply and apply the glue 24 thereon.

It should be emphasised that the point along the contour 27 of the insole 23 from where the nozzles 22 start to supply the glue depends on the configuration of the plate 19 or more precisely on the segments 19a of thereof. Basically, the nozzles 22 are positioned so as to start from behind the plate 19.

After the glue 24 has been applied to the contour 27 of the insole 23, the means 14 are first actuated so as to fold back the edges of the upper 21 towards the insole and, then, subsequently, also the means 16 are actuated so as to press from underneath the edges themselves against the insole 23, thereby ensuring that the upper 21 is glued to the insole 23.

With regard to that described above, it is obvious that the configuration assumed by the supply plate 19, or rather by the segments 19a, 19b thereof, allow adaptation to the different shapes and to the different dimensions of the insole 23, without having to change the supply plate 19. Thus, for example, it is possible to hingeably adjust the segments of the supply plate 19 so as to make them suitable for the inner soles of shoes with a square or rounded toe. The nozzles 22 are also able to apply perfectly the glue 24 along the contour 27 of insoles which have different shapes.

It is obvious that, in the case where the machine is provided with the means for hingeably arranging the supply plate and with the control and adjusting means described above, the operation of hingeably adjusting the plate 19 so as to adapt it to the shape of an insole 23 may be advantageously performed automatically rather than manually.

As can be appreciated from that described above, the machine for manufacturing shoes according to the invention is able to satisfy the requirements referred to in the introductory part of the present description and at the same time overcome the drawbacks associated with the machines of the known art.

In fact, the machine for manufacturing shoes according to the invention is able to perform gluing of the upper to insoles of various dimensions and with different shapes without having to replace any parts.

Another advantage of the machine for manufacturing shoes according to the invention lies in the fact that operation thereof may be completely automated.

Obviously a person skilled in the art, in order to be able to satisfy contingent and specific requirements, may make numerous modifications and variations to the machine for manufacturing shoes described above, all of which are contained within the protective scope of the invention as described by the claims which follow.