WO2006111995A1

WO2006111995A1 - Shoe last and process for handling shoe lasts

Info

Publication number: WO2006111995A1
Application number: PCT/IT2006/000254
Authority: WO
Inventors: Tommaso Sestini
Original assignee: ROBOT SYSTEM Srl
Current assignee: ROBOT SYSTEM Srl
Priority date: 2005-04-21
Filing date: 2006-04-14
Publication date: 2006-10-26
Anticipated expiration: 2007-10-21
Also published as: BRPI0609218A2; ITFI20050076A1; BRPI0609218B1

Abstract

Shoe last comprising at least one cavity (3; 7; 8) which is longitudinally- directed according to a predetermined angle in relation to a reference line (L) of the shoe last, said cavity having a predetermined length and being provided on each of the two sides of the shoe last neck portion.

Description

TITLE

"Shoe last and process for handling shoe lasts"

DESCRIPTION

The present invention relates to a shoe last and to a process for handling shoe lasts.

It is known that the manufacturing of shoes requires the use of shoe lasts onto which shoe vamps or uppers are fitted. It is also known that the shoe lasts employed in shoe industry on this purpose allow not only the so called lasting but also the automated motion of the shoes between different operating stations of the production plants .

At present, shoe lasts provided with a profiled insert emerging from their neck portion are commonly used in shoe manufacturing, as said insert acts as a hold extension and as a position reference for the automatic manipulation and motion systems. However, the manufacturing of shoe lasts provided with such inserts requires relatively high expenses in comparison with the current production requirements and it is even more evident if the large number of shoe lasts with different shapes and sizes used in a shoe factory is taken in consideration.

The main aim of the present invention is that of overcoming the above drawbacks .

According to the invention, these results have been achieved thanks to the idea of manufacturing a device and of carrying out a process having the features described in the independent claims. Further features of the invention are the subject of the dependent claims. Thanks to the present invention, it is possible to provide a correct and precise hold of the shoe last as regards its position, and, at the same time, to guarantee reduced manufacturing costs of the shoe last itself. Moreover, a shoe last according to the present invention is easy to manufacture and reliable even after a long and repeated use.

These and other advantages and characteristics of the invention will be best understood by anyone skilled in the art from a reading of the following description in conjunction with the attached drawings given as a practical exemplification of the invention, but not to be considered in a limitative sense, wherein:

-Fig. 1 shows a schematic side view of a shoe last according to a possible embodiment of the present invention;

-Fig. 2A shows a top plan view of the shoe last of Fig.l;

-Fig. 2B shows the enlarged circled detail of Fig. 2A, in a horizontal section view;

-Fig.3 shows a schematic section view along the line R-R of the shoe last of Fig. 2A;

-Fig. 4 shows a schematic side view of a shoe last according to a further embodiment of the present the invention;

-Fig. 5 shows a section view along the line x-x of the shoe last of Fig.4;

-Fig. 6 shows a section view along the line y-y of the shoe last of Fig. 5;

-Figs. 7-9 show three operative steps in which the shoe last of Figs. 4-6 is grasped by an automatic manipulator;

-Fig. 10 shows a view from K of the unit shown in Fig 7;

-Figs 11-13 show three operative steps in which the shoe last of Figs. 1-3 is grasped by an automatic manipulator;

-Fig 14 shows a view from J of the unit shown in Fig. 11;

-Figs 15-19 schematically show the use of the shoe last of Figs 4-6 for a shoe having a high necked upper or vamp;

-Figs.20-22 show yet another example of a shoe last according to the present invention.

Seen in its essential structure and with reference to the enclosed drawings, a shoe last according to the present invention, denoted by the numeral reference (1) , features at least one cavity or depression on both sides of the neck which is directed according to a predetermined angle in relation to a reference line, such as line (L) of the foot sole and having a predetermined length starting from the heel area. In the examples shown in the drawings, each side of the shoe last neck (1) is provided with two cavities (3; 7; 8) which are parallel to each other and to line (L) of the foot sole and positioned at a predetermined distance from each other. As described more in detail in the following, said cavities (3;7;8), can be provided, for example, by executing a milling process directly on the shoe last, which can be made of plastic material according to a well known manufacturing method, so as to form a precise position reference for the systems currently used for automatically holding and moving the shoe lasts.

With reference to the example shown in Figs 4-6 of the enclosed drawings, said cavities (7,8) feature a rectangular cross section. Each of the two upper cavities (8) is provided with a central conical blind hole (6b) whose axis is perpendicular to the longitudinal axis of the cavity itself and whose function is described below. A bushed hole (4) is provided on shoe last neck (1), like in conventional shoe lasts.

A possible use of this shoe last is schematically illustrated in Figs 7-10, which show a pneumatic clamp (10) provided with parallel jaws (11) . Upper faces (8M) and lower faces (7M) of the two jaws (11) project toward the inside of the clamp so as to form four corresponding male elements which are intended to be introduced into the four cavities (7,8) of each shoe last (1). Moreover, the centre of each of said upper faces (8M) features a conical pin (6M) mounted on a corresponding bucket spring (or on a similar type of spring) . In order to obtain the hold of shoe last (1) the clamp (10) is positioned with its jaws (11) over the shoe last (as shown in Fig 7, wherein Y indicates a vertical axis which is perpendicular to the common axis of conical holes 6b of the shoe last, along which axis the clamp is moved by means of corresponding motion means which are per se known) . Thereafter, the clamp is lowered (Fig.8) and jaws (11) are closed (Fig.9) and their faces (7M,8M) are introduced into cavities (7,8) while pins (6M) are introduced into the centering holes (6b) . As conical pins (6M) are mounted on springs, a possible transverse positioning error (z) of the clamp in relation to the shoe last is automatically corrected, so as to allow faces (7M,8M) of jaws (11) to match the bottom of cavities (7,8) with very high precision.

A further possible use of a shoe according ti the present invention is shown in Figs 15-19, wherein the reference numeral (12) indicates a shoe with a high necked upper or vamp mounted on shoe last (1), the reference numerals (10,11) indicates the clamp described above and the reference numerals (15,18) indicate an extension tongs. The latter is provided with normally closed jaws (13) featuring curved tips (16) and is intended to be hooked to the upper cavities (7) of shoe last (1) as shown in Figs 17-19; in other words, the lower ends of extension tongs are positioned between the upper neck (12) and the shoe last neck (1) , with the tips (16) inside the upper cavities (7) of the shoe last itself. The head portion (15) of said extension means is provided with two cavities (13,14) on both sides and a conical central blind hole (15) so as to reproduce the shape of the shoe last (1) described above. In this way, it is possible to obtain a correct hold and motion of the shoe last (1) by means of the clamp (10) even when cavities (7,8) of the shoe last are covered by the upper of the shoe to be manufactured.

With reference to the example shown in Figs 1-3, said cavities (indicated with the reference numeral 3 in these figures) feature a semicircular profile and a cylindrical insert (2) is mounted on each of them. Each of said inserts (2) is provided with a conical central hole an with two passing holes which are provided on both sides of the central one to allow the coupling of the insert to the shoe last (1) by using screwing means. These screwing means, as illustrated in Figs 2B and 3, transversely pass through shoe last neck (1) so that each insert (2) is attached to the insert positioned on cavity (3) on the other side of shoe last neck, at the same height. Figs. 11-14 show a possible use of the shoe lasts just now described. In this case, internal faces (2F) of the jaws (11) of clamp (10) feature a female profile (instead of a male profile like in the examples of Figs 7-19) . The holding of the shoe last by means of the clamp (10) corresponds to that described above.

Reference being made to the example shown in Figs. 20-22, the shoe last (1) is provided with cavities (3) on both sides of the neck portion (100) like in the previously described examples. A centering hole (101) is provided on top of said neck portion (100) . A pneumatically actuated clamp (102) is used to grasp the shoe last (1) , said clamp (102) being provided with two jaws whose tips (103) have the same profile of the cavities (3). The clamp (102) is provided, at a fixed point between said jaws, with a centering pin (104) having the same function of the pins (6M) previously described but allowing a less stretching of the shoe upper or vamp when it grasps the shoe last (1) .

Said cavities (3; 7; 8) may feature any type of suitable cross section, even a "V" section, for example. Moreover, said cavities (3; 7; 8) can be made on used shoe lasts, that is by milling shoe lasts which already existing in shoe factories and used for shoes production. In all cases described above, said cavities (3; 7; 8) provide a precise positional reference for the automatic holding and motion means, as regards both the angular direction in relation to a reference line, such as the foot sole line (angular positioning) and in relation to the heel area (longitudinal positioning) . Moreover, in all the cases described above, the shoe last is held on both sides of the shoe neck portion.

Practically speaking, in any case, the execution details can vary equally, regardless of the shape, dimensions, disposition of elements and materials used, without, however, departing from the adopted solution idea and thus remaining within the protection offered by the present patent.

Claims

1) Shoe last characterised in that it comprises at least one cavity (3;7;8) which is longitudinally directed according to a predetermined angle in relation to a reference line (L) of the shoe last, said cavity having a predetermined length and being provided on each of the two sides of the shoe last neck portion.

2) Shoe last according to claim 1 characterised in that it comprises two cavities (3; 7; 8) on each side of the neck portion, said cavities (3;7;8) being parallel to each other.

3) Shoe last according to claims 1 or 2 characterised in that said cavities (7,8) feature a rectangular transverse section.

4) Shoe last according to claims 1 or 2 characterised in that said cavities (3) feature a semicircular transverse section.

5) Shoe last according to claim 3 characterised in that said cavities (7,8) feature a conical central hole (6b) whose axis is orthogonal to the longitudinal development direction of the cavities.

6) Shoe last according to claim 3 characterised in that a cylindrical insert (2) is applied to each of said cavities, being said insert (2) provided with a central conical hole (6) whose axis is perpendicular to the longitudinal development axis of the insert itself.

7) Shoe last according to claim 6 characterised in that said inserts (2) are connected two by two by screw means (5) which pass through the neck of shoe last (1) so that each insert (2) is connected to the insert positioned on cavity (3) on the other side on the neck of the shoe last, at the same height.

8) Process for handling shoe lasts characterised in that it comprises a step of holding the shoe lasts on both sides of the respective neck portion 9) Process according to claim 1 characterised in that said hold is carried out on at least one cavity on each of the two sides of the neck portion.

10) Process according to claim 1 characterised in that said hold is carried out on an insert applied on at least one cavity on each of the two sides of the neck portion.