GB2105252A

GB2105252A - Production of footwear with a two-coloured moulded sole

Info

Publication number: GB2105252A
Application number: GB08224540A
Authority: GB
Inventors: Alec Roy Bromfield
Original assignee: BLISS PAUL THOMAS; GEMINDER RODNEY IAN PETER
Current assignee: BLISS PAUL THOMAS; GEMINDER RODNEY IAN PETER
Priority date: 1981-08-27
Filing date: 1982-08-26
Publication date: 1983-03-23

Abstract

A shoe having a two-component (e.g. two-coloured) moulded sole is produced by: (1) closing a first mould (14, 18, 22) with a shoe upper (10) on a last (12), and moulding a first sole layer (26) onto it; and subsequently (2) closing a second mould (40, 44) with the last (12)/upper (10)/first layer (26), and moulding a second sole layer (50) adhering to the first. The first layer (26) may have a depending skirt (30) which seals the second mould, which may have an outwardly tapering mouth portion (42) to facilitate insertion. <IMAGE>

Description

SPECIFICATION Production of footwear with moulded sole This invention relates to the production of shoes and other footwear having a moulded sole. In this context, the term "sole" refers to the entire groundengaging lower part of the shoe, including the heel.

The term "shoe" will also be used herein generically to include all known types offootwearto which the present invention might be applied.

Moulded soles on shoes have been known for many years. Typically soles are moulded from rubber, polyurethane or other polymeric material. More recently, casual shoes and sports shoes are produced which are intended to have a more striking appearance than conventional shoes, and in particularthe use of two or more colours in the shoe has become common. More especially, the production of moulded soles in two colours has become fashionable. There are various ways of doing this, but the commonly used methods generally involve the use of moulding machines with two feed mechanisms for the two differently coloured polymeric materials, or the use of complex machines for changing the mould between the production of the differently coloured layers.

The present invention seeks to provide a method for producing a shoe with a two-coloured moulded sole, in which simple and relatively inexpensive equipment is used, thereby making it more appropriate for small scale operation.

According tothe present invention there is provided a method of producing footwear with a moulded sole, comprising closing a first mould with a lasted upper and moulding therein a first sole layer, removing the product from the first mould and introducing it into a second mould so that the latter is closed by the first sole layer, and moulding therein a second sole layer which welds to the first sole layer. The first sole layer preferably includes a peripheral depending skirt which seals against the sides of the second mould.

In order that the invention may be more clearly understood, one embodiment will now be described with reference to the accompanying drawings, wherein: Fig. 1 shows a transverse cross-sectional view of the moulding of the first sole layer, and Fig. 2 shows a similar cross-sectional view of the moulding of the second sole layer.

Referring to the drawings, and firstly to Fig. 1; a shoe upper 10 is carried on a last 12 in preparation for moulding a sole thereto. A first mould comprises a main block 14 having a cavity whose side walls 16 define the plan outline of the sole. A bottom closer member 18 is located in the cavity and its top surface 20 provides the base for the mould cavity. A lip plate 22 is located on the block 14, and has an opening whose edge 24 is the same general shape as the outline of the mould cavity side wall 16, but slightly smaller. The lasted upper 10 closes the top of the mould by fitting into the opening in the lip plate, as shown in Fig. 1. Polymeric material is then injected into the mould cavity to provide a first sole layer 26 fast with the shoe upper. The overhang 28 of the lip plate defines the top peripherally projecting surface of the sole.The surface 20 of the bottom closer 18 is lower around its periphery so that the first sole layer has a depending peripheral skirt 30.

After moulding the first sole layer, the lip plate is opened and the product (lasted upper with first sole layer) is removed from the mould. This is then transferred to a second mould, as shown in Fig. 2. The second mould comprises a block 40 having a mould cavity similar in plan to that of the first mould. However, the mouth of the mould is upwardly flared somewhat at 42. The bottom closer member 44 located in the mould cavity has a top surface 46 which is shaped to define the bottom surface ofthe sole of the shoe. The lasted upper carrying the first sole layer is introduced into the top of this second mould. The sloping sides 42 at the mouth of the mould cavity enable the first mould layer 26 to enter the mould cavity, and guide the depending skirt 30 into the straight-sided portion 47 of the mould cavity.The extent to which the first sole layer is advanced down the straight-sided portion of the mould cavity depends upon the final thickness of the sole which is required. In the arrangement of Fig. 2, the lower edge 48 of the skirt is located a short distance above the top surface 46 ofthe bottom closer 44. Thus, when polymeric material is injected into the mould it occupies the downwardly opening cavity in the first sole layer defined by the skirt 30 and also a strip below the bottom edge of the skirt, forming a bottom sole layer 50 which can be of a different colour from the top sole layer 26. In this arrangement, therefore, the different colour of the bottom layer 50 appears not only on the bottom surface of the sole but also along a narrow strip running around the bottom side edge ofthe sole.

The second stage of the moulding process shown in Fig. 2 differs from that of the first stage in that no lip plate is required; the first mould layer 26 closing and sealing the mouth of the mould cavity. To assist in the successful moulding of the second layer, the polymeric material for the second layer is injected upwardly through the bottom closer 44 rather than horizontally from one end of the mould cavity. This upward pressure helps to expand the skirts 30 into firm contact with the cavity walls 46. The two-stage process is very simple to carry out, and does not require elaborate machinery; for example the provision of dual polymer injection machines or the provision of a reverible bottom closer to define on its two sides the bottom surfaces of the first and second sole layers respectively.

1. A method of producing footwear with a moulded sole, comprising closing a first mould with a lasted upper and moulding therein a first sole layer, removing the productfromthefirstmould and introducing it into a second mould so that the latter is closed by the first sole layer, and moulding therein a second sole layer which welds to the first sole layer.

2. A method according to claim 1 wherein the first and second sole layers differ in colour.

3. A method according to claim 1 or 2 whereir

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Production of footwear with moulded sole This invention relates to the production of shoes and other footwear having a moulded sole. In this context, the term "sole" refers to the entire groundengaging lower part of the shoe, including the heel. The term "shoe" will also be used herein generically to include all known types offootwearto which the present invention might be applied. Moulded soles on shoes have been known for many years. Typically soles are moulded from rubber, polyurethane or other polymeric material. More recently, casual shoes and sports shoes are produced which are intended to have a more striking appearance than conventional shoes, and in particularthe use of two or more colours in the shoe has become common. More especially, the production of moulded soles in two colours has become fashionable. There are various ways of doing this, but the commonly used methods generally involve the use of moulding machines with two feed mechanisms for the two differently coloured polymeric materials, or the use of complex machines for changing the mould between the production of the differently coloured layers. The present invention seeks to provide a method for producing a shoe with a two-coloured moulded sole, in which simple and relatively inexpensive equipment is used, thereby making it more appropriate for small scale operation. According tothe present invention there is provided a method of producing footwear with a moulded sole, comprising closing a first mould with a lasted upper and moulding therein a first sole layer, removing the product from the first mould and introducing it into a second mould so that the latter is closed by the first sole layer, and moulding therein a second sole layer which welds to the first sole layer. The first sole layer preferably includes a peripheral depending skirt which seals against the sides of the second mould. In order that the invention may be more clearly understood, one embodiment will now be described with reference to the accompanying drawings, wherein: Fig. 1 shows a transverse cross-sectional view of the moulding of the first sole layer, and Fig. 2 shows a similar cross-sectional view of the moulding of the second sole layer. Referring to the drawings, and firstly to Fig. 1; a shoe upper 10 is carried on a last 12 in preparation for moulding a sole thereto. A first mould comprises a main block 14 having a cavity whose side walls 16 define the plan outline of the sole. A bottom closer member 18 is located in the cavity and its top surface 20 provides the base for the mould cavity. A lip plate 22 is located on the block 14, and has an opening whose edge 24 is the same general shape as the outline of the mould cavity side wall 16, but slightly smaller. The lasted upper 10 closes the top of the mould by fitting into the opening in the lip plate, as shown in Fig. 1. Polymeric material is then injected into the mould cavity to provide a first sole layer 26 fast with the shoe upper. The overhang 28 of the lip plate defines the top peripherally projecting surface of the sole.The surface 20 of the bottom closer 18 is lower around its periphery so that the first sole layer has a depending peripheral skirt 30. After moulding the first sole layer, the lip plate is opened and the product (lasted upper with first sole layer) is removed from the mould. This is then transferred to a second mould, as shown in Fig. 2. The second mould comprises a block 40 having a mould cavity similar in plan to that of the first mould. However, the mouth of the mould is upwardly flared somewhat at 42. The bottom closer member 44 located in the mould cavity has a top surface 46 which is shaped to define the bottom surface ofthe sole of the shoe. The lasted upper carrying the first sole layer is introduced into the top of this second mould. The sloping sides 42 at the mouth of the mould cavity enable the first mould layer 26 to enter the mould cavity, and guide the depending skirt 30 into the straight-sided portion 47 of the mould cavity.The extent to which the first sole layer is advanced down the straight-sided portion of the mould cavity depends upon the final thickness of the sole which is required. In the arrangement of Fig. 2, the lower edge 48 of the skirt is located a short distance above the top surface 46 ofthe bottom closer 44. Thus, when polymeric material is injected into the mould it occupies the downwardly opening cavity in the first sole layer defined by the skirt 30 and also a strip below the bottom edge of the skirt, forming a bottom sole layer 50 which can be of a different colour from the top sole layer 26. In this arrangement, therefore, the different colour of the bottom layer 50 appears not only on the bottom surface of the sole but also along a narrow strip running around the bottom side edge ofthe sole. The second stage of the moulding process shown in Fig. 2 differs from that of the first stage in that no lip plate is required; the first mould layer 26 closing and sealing the mouth of the mould cavity. To assist in the successful moulding of the second layer, the polymeric material for the second layer is injected upwardly through the bottom closer 44 rather than horizontally from one end of the mould cavity. This upward pressure helps to expand the skirts 30 into firm contact with the cavity walls 46. The two-stage process is very simple to carry out, and does not require elaborate machinery; for example the provision of dual polymer injection machines or the provision of a reverible bottom closer to define on its two sides the bottom surfaces of the first and second sole layers respectively. CLAIMS

3. A method according to claim 1 or 2 whereir the first sole layer includes a peripheral depending skirt which seals against the sides of the second mould.

4. A method according to any preceding claim wherein the second mould has sloping sides adjacent its mouth to facilitate introduction of the first sole layer, said first layer being introducible into the second mould to an extent which is selected in dependence on the desired final thickness of the sole.

5. A method according to any preceding claim wherein the material for moulding the second sole layer is injected upwardly through the bottom ofthe second mould.

6. A method of producing footwear substantially as described herein with reference to the accompanying drawings.

7. Footwear produced by a method according to any preceding claim.