GB2053073A

GB2053073A - Making a plastics shoe sole, with stiletto heel

Info

Publication number: GB2053073A
Application number: GB8018806A
Authority: GB
Original assignee: PAMA SpA
Current assignee: PAMA SpA
Priority date: 1979-06-20
Filing date: 1980-06-09
Publication date: 1981-02-04
Also published as: DE3022487A1; FR2459015A1

Abstract

A sole (13) and high heel (23) produced by moulding in a die, and made of plastics material, in which heel (23) a tubular metallic pin (11) is embedded, characterized by the fact that to the lower end of the pin there is applied a centering element (18), (19) which locates the pin (11) in the die during moulding, and has a star-shaped head (18) which allows the moulding plastics to substantially embed it. The centering element remains incorporated in the formed heel, which can also include a plastics insert (12) joined to a metal sole plate (14). <IMAGE>

Description

SPECIFICATION Sole made of plastics material for shoes, with improved stiletto heel The present invention relates to a sole made of plastics material for shoes, with improved stiletto heel.

The sole forming subject matter of the present invention has a very thin high heel (socalled Louis XV heel for ladies' shoes), and is characterized by the fact that a tubular metallic pin is let into the heel for its entire height, and by the fact that there is let into the inner sole an elastically yieldable metallic lamina extending from the top of the heel, essentially as a prolongation of the pin.

There is in this way created a high-heeled sole made of plastics material in which the heel possesses elevated resistance to combined bending and compressive stress as a result of the tubular metallic pin, and in which the inner sole offers an outstandingly comfortable support because of the elastically yieldable metallic lamina let into it.

The said pin can be let into the heel directly, during the forming of a sole in a single piece, or can first be let into a heel-shaped sub-assembly made of rigid plastics material, which will subsequently be let into the sole when this is formed.

In either case, when the heel is very thin, if the pin or the sub-assembly in which it is embedded is not perfectly centered within the forming die, the outer material often fails to be of uniform thickness around the core (pin or sub-assembly) in some cases even, parts of said core remain bare, with the obvious problems this causes.

The purpose of the present invention is to obviate the aforesaid defects, and to this end a sole of the aforesaid type has been devised characterized by the fact that the lower end of the pin has applied to it a centering element containing passages for the sole-forming material, said element remaining incorporated within the formed heel.

The structural and functional characteristics of the invention and its advantages over the known art are made even clearer by the following exemplifying description, referred to the attached drawings in which: Figure 1 is a longitudinal section view illustrating a sole produced according to the said invention.

Figure 2 is an enlarged view of a particular of the heel end of Fig. 1, inserted into a soleforming die, in the direction of the line Il-Il of Fig. 3; and Figure 3 is a section view in the direction of the line Ill-Ill of Fig. 2.

In the drawings, the high-heeled sole in question is indicated overall by 10, and is made of a suitable plastics material such as for example PVC, ABS resins, polyurethane foams, etc.

A tubular metallic pin 11 is let into the heel of the sole 10, and said pin provides elevated resistance to the considerable combined bending and compressive stresses to which the high-heels of ladies' are subjected.

The pin 11 can be let into the heel directly, during the forming of a sole in a single piece, or can first be let into a sub-assembly 12, made of rigid plastics material shaped in the form of a heel, which will then be let into the sole when this is formed.

A metallic, elastically yieldable lamina 14 is embedded in the inner sole 13: said lamina extends from the top of the heel where the lamina presents a clamping fold 15 to the sub-assembly 12, as extension of the pin 1 1; it is centrally ribbed, as shown at 16.

It will thus be seen that a sole of such structure is extremely strong and at the same time sufficiently comfortable as a result of the combined insertion of the pin 11 and lamina 14: these, by virtue of their elasticity and combined action, wholly prevent any sudden and physically dangerous collapsing of the heel, as occurs in general when rigid inserts are employed.

It should, moreover, be noted that the lamina 14 can also form part of the sub-assembly 12 which is subsequently let into the plastics material when the sole is formed.

According to the present invention, at the time the sole is formed a centering element 17, made for example of plastics material, is applied to the lower end of the pin 11. This element 17 consists of a star-shaped centering head 18 and a tang 19, formed in a single piece with the said centering head. The said element is inserted, for the entire length of the tang, into the lower end of the pin 1 1; to ensure that it is securely fixed thereto, a nail 20 is implanted in it and expands the tang, the outer wall of which thus brings pressure to bear against the inner wall of the pin. In this way, the centering element is safely secured and prevented from accidental egress during the various sole forming steps.

By coming to bear with its tips 21 on the inner surface of the die 22, the centering head 18 assures the centering of the pin 11, and thus of the sub-assembly 12, within the said die, so that the outer or covering material 23 has a uniform thickness on all sides of the heel.

As a result of its star-configuration, the centering head 18 forms, in conjunction with the die 22, passages 24 for the covering material 23, which can thus enclose the said head 18.

1. A sole produced by forming in a die, and made of plastics material, of the type with very thin high-heels, in which a tubular metallic pin is embedded, characterized by the fact

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Sole made of plastics material for shoes, with improved stiletto heel The present invention relates to a sole made of plastics material for shoes, with improved stiletto heel. The sole forming subject matter of the present invention has a very thin high heel (socalled Louis XV heel for ladies' shoes), and is characterized by the fact that a tubular metallic pin is let into the heel for its entire height, and by the fact that there is let into the inner sole an elastically yieldable metallic lamina extending from the top of the heel, essentially as a prolongation of the pin. There is in this way created a high-heeled sole made of plastics material in which the heel possesses elevated resistance to combined bending and compressive stress as a result of the tubular metallic pin, and in which the inner sole offers an outstandingly comfortable support because of the elastically yieldable metallic lamina let into it. The said pin can be let into the heel directly, during the forming of a sole in a single piece, or can first be let into a heel-shaped sub-assembly made of rigid plastics material, which will subsequently be let into the sole when this is formed. In either case, when the heel is very thin, if the pin or the sub-assembly in which it is embedded is not perfectly centered within the forming die, the outer material often fails to be of uniform thickness around the core (pin or sub-assembly) in some cases even, parts of said core remain bare, with the obvious problems this causes. The purpose of the present invention is to obviate the aforesaid defects, and to this end a sole of the aforesaid type has been devised characterized by the fact that the lower end of the pin has applied to it a centering element containing passages for the sole-forming material, said element remaining incorporated within the formed heel. The structural and functional characteristics of the invention and its advantages over the known art are made even clearer by the following exemplifying description, referred to the attached drawings in which: Figure 1 is a longitudinal section view illustrating a sole produced according to the said invention. Figure 2 is an enlarged view of a particular of the heel end of Fig. 1, inserted into a soleforming die, in the direction of the line Il-Il of Fig. 3; and Figure 3 is a section view in the direction of the line Ill-Ill of Fig. 2. In the drawings, the high-heeled sole in question is indicated overall by 10, and is made of a suitable plastics material such as for example PVC, ABS resins, polyurethane foams, etc. A tubular metallic pin 11 is let into the heel of the sole 10, and said pin provides elevated resistance to the considerable combined bending and compressive stresses to which the high-heels of ladies' are subjected. The pin 11 can be let into the heel directly, during the forming of a sole in a single piece, or can first be let into a sub-assembly 12, made of rigid plastics material shaped in the form of a heel, which will then be let into the sole when this is formed. A metallic, elastically yieldable lamina 14 is embedded in the inner sole 13: said lamina extends from the top of the heel where the lamina presents a clamping fold 15 to the sub-assembly 12, as extension of the pin 1 1; it is centrally ribbed, as shown at 16. It will thus be seen that a sole of such structure is extremely strong and at the same time sufficiently comfortable as a result of the combined insertion of the pin 11 and lamina 14: these, by virtue of their elasticity and combined action, wholly prevent any sudden and physically dangerous collapsing of the heel, as occurs in general when rigid inserts are employed. It should, moreover, be noted that the lamina 14 can also form part of the sub-assembly 12 which is subsequently let into the plastics material when the sole is formed. According to the present invention, at the time the sole is formed a centering element 17, made for example of plastics material, is applied to the lower end of the pin 11. This element 17 consists of a star-shaped centering head 18 and a tang 19, formed in a single piece with the said centering head. The said element is inserted, for the entire length of the tang, into the lower end of the pin 1 1; to ensure that it is securely fixed thereto, a nail 20 is implanted in it and expands the tang, the outer wall of which thus brings pressure to bear against the inner wall of the pin. In this way, the centering element is safely secured and prevented from accidental egress during the various sole forming steps. By coming to bear with its tips 21 on the inner surface of the die 22, the centering head 18 assures the centering of the pin 11, and thus of the sub-assembly 12, within the said die, so that the outer or covering material 23 has a uniform thickness on all sides of the heel. As a result of its star-configuration, the centering head 18 forms, in conjunction with the die 22, passages 24 for the covering material 23, which can thus enclose the said head 18. CLAIMS

1. A sole produced by forming in a die, and made of plastics material, of the type with very thin high-heels, in which a tubular metallic pin is embedded, characterized by the fact that to the lower end of the pin there is applied a centering element presenting passages for the plastics material used for the forming of the sole, said centering element remaining incorporated within the formed heel.

2. A sole according to claim 1, characterized by the fact that said centering element consists essentially of a centering head containing passages for the sole-forming material and of a tang for securing said centering element to said pin, within which tang is implanted a plug element for expanding the tang against the inside walls of said pin.

3. A sole according to claim 2, characterized by the fact that said centering head is substantially star-shaped so as to form the said passages in conjunction with the wall of the die.

4. A sole substantially as hereinbefore described with reference to and as shown in the accompanying drawings.