US3671989A

US3671989A - Support for a last used in a device for molding shoe soles

Info

Publication number: US3671989A
Application number: US79945A
Authority: US
Inventors: Ryck Petrus De
Original assignee: ACEC SA
Current assignee: Umicore NV SA
Priority date: 1969-10-16
Filing date: 1970-10-12
Publication date: 1972-06-27
Anticipated expiration: 1989-06-27
Also published as: GB1327078A; BE740379A; FR2066053A5; DE2050384A1

Abstract

A support for a last used in the molding of shoe soles. The support includes means for positioning the last with respect to the support and magnetic means associated with the support and the last for securing the last to the support. The magnetic means includes a magnet secured to the support and a piece of magnetic material fixed on the side of the last opposite to the sole. The last is made of non-magnetic material.

Description

[ 51 June 27, 1972 [54] SUPPORT FOR A LAST USED IN A DEVICE FOR MOLDING SHOE SOLES [72] Inventor: Petrus R. Deryck, Oordegem, Belgium [73] Assignee: ACEC Atelius de Constructions Electriques de Charleroi, Charleroi, Belgium [22] Filed: Oct. 12,1970

[2|] Appl.No.: 79,945

[30] Foreign Application Priority Data Sept. 16, 1969 Belgium ..so373 [52] U.S.Cl ..12/123 [51] Int. Cl. ....,A43d 3/00 [58] Field ofSearch ..12/123,126,127,142 R, 128 D [56] References Cited UNITED STATES PATENTS 3,092,861 6/1963 Reid et al. ..12/142 R 3,166,771 1/1965 Klineetal ..l2/123X 101,151 3/1870 Moyonetal ..l2/127X Primary Examiner-Patrick E. Lawson Attorney-Raymond A. Robic [5 7] ABSTRACT A support for a last used in the molding of shoe soles. The support includes means for positioning the last with respect to the support and magnetic means associated with the support and the last for securing the last to the support. The magnetic means includes a magnet secured to the support and a piece of magnetic material fixed on the side of the last opposite to the sole. The last is made of non-magnetic material.

5 Claims, 2 Drawing Figures l l l 6 PATENTEnJum I972 3.671.989

sum 1 or 2 INVENTOR Petrus R. De RYC|$ ATTORNEY surronr son A LAST USED IN A DEVICE son MOLDING suoa sows The invention relates to a support for a last used in the molding of shoe soles.

The known devices for molding shoe soles comprise at least one mold, a last which may be adapted to the mold, a support for such last, means for operating such support, and an injection head which is at least temporarily connected with the mold.

In the known devices of this type, the last is fixed to the support by means of screws or bolts. The replacement of such a last, which is usually madeof metal, therefore takes a relatively long period of time. In these devices, it would take too much time to replace the last by another one after each injection of a sole. Consequently, after each molding of a sole, the top which normally covers the last is taken off with the sole and a new top is placed on the last for molding a new sole thereof;

Since the top, at leastfor the shoes which are mechanically manufactured, is placed on a last madeof a cheap material, such as wood, it becomes necessary in the known devices to remove the top from the last and to place it on the last of the device. This displacement of the top also takes time, although the time taken is a little bit less than the one for the replacement of the last. The removal of the top from the last and the placing of the same on another last may also damage the top.

In other known devices for molding shoe soles, the top is not fixed on a support. The-last covered by the top is placed on an injection mold which is in a horizontal position and, before injection, the last is pressed with a predetennined pressure against the mold. In these known devices, the lasts on which the tops have been placed are used directly to form the mold so that there is no time lost in changing the tops from one last to the other but there is however a risk that the last covered by the top may not be placed in the right way with respect to the mold. Such would result in a shoe of bad quality or even in a shoewhich would not be usable. In addition, when the last is pressed against the mold, the material of the top which is often leather may be damaged by the mold itself and, by the nature of such devices, the mobile parts of the mold must be coupled together before the last is applied thereon. The last is indeed only retained by the mold. In the manufacture of shoes, it is advantageous thatthe parts of the mold may not be coupled until after insertion of the last in the mold, which permits to the mold to partially encircle the top. This gives a better shape to the finished shoe.

The object of the invention is thus to provide a shoe mold ing device in which the last is fixed to a support and in which the parts.of-the mold may be coupled afier insertion of the last, while the lasts are very easily and rapidly interchangeable so that such lasts on which the tops are placed may be used directly to close the mold during the molding operation.

To obtain the above result, the support is provided with means for positioning the last with respect to the support, and the last is fixed to the support by a magnetic link.

In a particular form of the invention, one of the elements of the assembly formed by the support and the last is provided with a magnet while the other element consists of, at least partially, a metal which is attracted by such a magnet.

Preferably, the magnet is fixed to the support while the last is made of a material which is not attracted by a magnet but is provided with a piece of magnetic material on the side thereof opposite to the sole.

In a preferred embodiment of the invention, the means for positioning the last with respect to the support includes five rods which are adjustable in height and with respect to the support. 1

In an embodiment of the invention which is particularly useful, the support is provided with an adjustable supporting post for the front part of the last.

Other characteristics of the invention will be more clearly understood from the following description of a shoe molding device in accordance with the invention, such description being given by way of example only and with reference to the following drawings in which:

FIG. 1 is a plan view of the support of a device in accordance with the invention; and

FIG. 2 is a side view of the support of FIG. 1 upon which is secured a last covered by a top.

In both Figures of drawings the same reference numerals have been used to designate the same elements.

The device illustrated in the drawings includes a pivotable arm 1 upon which is fixed the support of a last. Such support comprises two

parallel plates

2 and 3 maintained at a predetermined distance from each other by spacing devices 4. Plate 2 which is the mostremote from arm 1, is spaced from plate 3 towards the outside thereof. On plate 2 there are five rods each one of which includes a portion 5 fixed to the plate and a portion 6 which is adjustable in height with respect to the plate 2. The portion 5 of each rod has a threaded end which protrudes through a slot 7 in plate 2. On such threaded end, on the side of plate 2 which is facing plate 3, is screwed a nut 8. By unscrewing such nut 8, the portion 5 of each rod may be displaced a predetennined distance in the longitudinal axis of the slot, which is perpendicular to the closest edge of the plate 2. The portion 5 of each rod has at its end which is most remote from plate 2, a nut 9 in which is threaded portion 6 of the rod. By rotating such portion 6, the upper end thereof may be adjusted in height with respect to the plate 2 Along the transversal edge of the plate 2 which is most remote from the axis of rotation of arm 1, there is a supporting post comprising a cylindrical portion 10 fixedto plate 2 and a portion 11 which is adjustable in height with respect to plate 2. Portion 10 of the supporting post has a threaded end protruding through a slot 12 in plate 2. The longitudinal axis of such slot is perpendicular to the edge of plate 2 which is most remote from the axis of rotation of arm 1. On the threaded end of portion 10 of the supporting postthere is a nut 13. By un-, screwing such nut, the portion 10 may be moved in the longitudinal axis of slot 12. The upper end of portion 10 of the supporting post has a nut 14 into which is threaded portion 11 of the post. Such portion has at its upper end a head 15 whose surface opposite to plate 2is curved and covered by a layer of rubber 16.

Between the five

rods

5, 6 and the supporting

post

10, 11

there is a permanent magnet in the shape of bar 17. Such magnet is fixedin an adjustable manner at the center of a plate 18 which is made in an H shape. The ends of the legs of plate 18 have holes therein through which pass threaded rods 19 which are fixed to plate 2. Each end of the legs are secured between two washers 20 placed between two nuts 21 which are tightened on the respective rods 19. By screwing or unscrewing nuts 21, the support plate l8'may be adjusted in height with respect to plate 2.

The device in accordance with the invention comprises wooden lasts 22 having at the end thereof opposite the sole an iron plate 23. In FIG. 2, such a last covered by a top 2 4 is illustrated on the support. The

rods

5, 6 are placed in such a way that, when a last come in contact with magnet 17 by means of its iron plate 23, the last provided with its top is positioned in between the rods. The supporting

post

10, 11 is placed in such a way that when the last is placed as mentioned above, its forward end rests on the supporting post. The risk of breaking the end of the last is thus eliminated.

The device also comprises a mold which has a frarnemade of several parts and which may be closed by thelast. Such mold as well as the molding head which is connected thereto are not shown in the drawings. The height of

rods

5, 6 is regulated in such a way that they do not interfere with the connection of the last to the frame.

The support of the last 22 is connected ,to a lever (not shown) which is provided with a roller rolling on a portion of the device. Such a lever causes the support to pivot. against the biasing force of a spring (not shown), with respect to arm 1 in such a manner that when the arm is pivoted, even though its end defines a circular path around its axis of rotation, the support is moved in a direction perpendicular to such axis or rotation and thus perpendicularly to the surface of the mold.

When a last 22 provided with a top 24 has been placed on the support, as illustrated in FIG. 2, the arm 1 is pivoted until the last contacts the mold. The portion of the frame of the mold may be coupled before, during or after the pivotal movement of the am. After the coupling of the parts of the mold and the positioning of the last, the mold is filled by injection of molding material. After the injection, the arm 1 is pivoted to bring such arm to its initial position and the last 22 is removed from the support. A new last including its top is subsequently placed on the magnet. Due to the magnetic link, the replacement of the last by another last may be done very rapidly. The magnet and more particularly the

rods

5, 6 and the supporting post 10 causes the last to be always placed in the right position with respect to the support and a suitable connection thereof to the mold. As a last, the last 22 on which the top has been made may thus be used.

The invention is not to be limited to the embodiment described above and, within the ambit of the present invention, a number of modifications may be made, more particularly concerning the shape, the composition, the disposition and the number of the pieces which may be used for the manufactun'ng of the support in accordance with the invention.

I claim:

1. A support for a last used in a device for the molding of shoe soles, comprising means for positioning the last with respect to the support and means for securing the last to the support including a magnet secured to the support and a piece of magnetic material fixed on the side of the last opposite to the sole, said last being made of non-magnetic material.

2. A support as defined in claim 1, wherein the last is made of wood and is provided on its side opposite the sole with an iron plate.

3. A support as defined in claim 1, wherein the support includes means for adjusting the height of the magnet.

4. A support as defined in claim 1 wherein the means for positioning the last with respect to the support include five rods which are adjustable in height and with respect to the support.

5. A support as defined in claim 1, further comprising a supporting post mounted on said support for supporting the front end of the last, said supporting post being adjustable in height.

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