GB1572115A - Mould for use in making a shoe - Google Patents

Description

(54) A MOULD FOR USE IN MAKING A SHOE (71) We, DESMA-WERKE Gesellschaft mit beschränkter Haftung, of Desmastrasse 3-5, 2807 Achim bei Bremen, Federal Republic of Germany, a Company organised under the laws of the Federal Republic of Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement::- This invention relates to an injection mould for use in making a shoe in which either or each of the sole and the upper comprises two or more parts made of different elastomers (as hereinafter defined), the mould comprising at least one bottom plate and side parts and a last and two separate injection passages for the injection in sequence of two different elastomers.

A comfortable and durable shoe may, for example comprise a two-layer sole and a multi- part upper of which the exterior consists in some regions exclusively of leather, and in other regions of elastomer, with an inner liner of "breathing" material.

Herein "shoe" includes any footwear article having a sole and an upper, for example a slipper or a boot; "elastomer" means mould axle flexible synthetic plastics material or rubber; "breathing" material means leather or textile fabric which is permeable to air and water vapour.

Shoes made wholly of elastomer, for example polyurethane, can be inexpensive and durable, but may be uncomfortable by causing accumulation of perspiration and heating of the wearer's feet, especially around and near the toes.

Shoes made wholly of leather, or of which the uppers consist of leather, can be comfortable but are more expensive than those of elastomer.

The invention is therefore intended to provide a mould to facilitate the manufacture of a shoe which can be economic to make and durable and comfortable in use.

According to the invention there is provided an injection mould for use in making a shoe (as hereinbefore defined) in which either or each of the sole and the upper comprises two or more parts made of different elastomers (as hereinbefore defined), the mould comprising at least one bottom plate and side parts and a last and two separate injection passages for the injection in sequence of two different elastomers, characterised in that these injection passages are arranged with at least their outlets one above the other and these outlets are separated from each other by a separator which extends between these outlets and is movable to facilitate the removal of deadheads from the lower one of said outlets.

In such a mould it is advantageous if there are sealing lips which in use extend along margins of a lasted leather upper exterior forward part and prevent elastomer from flowing out of the said mould cavity beyond the said margins.

The mould preferably comprises an insert piece which in use fits in a recess between the side parts and is provided with the said sealing lips.

How the invention may be put into practice appears from the following description with reference to the accompanying drawings, in which by way of example: Figure 1 shows a shoe in diagrammatic lateral elevation, Figure 2 shows an open mould for the production of a shoe according to Figure 1, partly in vertical section, Figure 3 shows a cross-section along the line III-III in Figure 2, Figure 4 shows a cross-section along the line IV-IV in Figure 2, Figure 5 is aviewpartlyinsectionofanother form of injection mould, for the production of a shoe according to Figure 1, Figure 6 shows a cross-section along the line VI-VI in Figure 5, Figure 7 shows a cross-section along the line VII-VII in Figure 5, Figure 8 shows another form of shoe in lateral elevation, Figure 9 is apartly sectional view of a mould for the production of a shoe according to Figure 8, Figure 10 shows a cross-section along the line X-X in Figure 9, Figure 11 shows a cross-section along the line XI-XI in Figure 9, Figure 12 shows an intermediate product for the production of a shoe of a different form, in longitudinal section, Figure 13 is a detail view in cross-section through a finished upper in the region of the transition between leather and synthetic plastics material, Figure 14 shows a detail of an injection mould, in plan view, Figure 15 shows a cross-section along the line XV-XV in Figure 14.

In the drawings there are illustrated three preferred examples of embodiment of shoes, and parts thereof.

In the shoe according to Figure 1, an outer sole 10 consists of synthetic plastics material or rubber, preferably of polyurethane. This outer sole 10 is connected, in the present case with interposition of an intermediate sole 12 likewise of synthetic plastics material, with an upper 11. The exterior of the upper 11 comprises two independently-made parts, namely a forward part 13 and a rear part 14.

The forward part 13 extends from the shoe toe to the beginning of lacing flaps 15. The forward edge of each flap 15 extends, with a seam 16, down as far as the outer sole 10 oras far as the intermediate sole 12. The seams 16 are approximately in the region of the greatest width of the shoe. The rear part 14 extends to the heel end.

The forward part 13 of the upper 11 consists exclusively of leather, while the adjoining rear part 14 is formed of elastomer, i.e. rubber or synthetic plastics material, preferably polyurethane. A tongue 17 of leather integrally adjoins the forward part 13.

An inner liner 18 (Figures 2, 9, 12) extends over at least the region of the rear part 14, but according to Figures 1 and 8 extends over the whole of the upper 11. This liner 18 consists of "breathing" material, for example of leather or a textile material. The synthetic plastics or rubber rear part 14 is externally moulded to this inner liner 18. In the sole region an inner sole 19 (Figures 2, 3), of leather adjoins the inner liner 18.

The transition between the forward part 13 of leather and the rear part 14 of synthetic plastics material or rubber is of importance.

The margin of the forward part 13 facing the rear part 14 is bevelled or sharpened, accordingly terminates with a sharp edge. The rear part 14 is formed thereto so that the sharpened margin of the forward part 13 is covered by rubber or synthetic plastics material. In this region moreover the optical impression of a seam is caused by appropriate shaping of the rubber or synthetic plastics material. So that the transition from one material to the other is not perceptible, the rear part 14 has on the outer surface a configuration corresponding to the surface structure of leather.

Figure 8 shows a shoe of the so-called moccasin type in which a front panel 20 is connected along an arcuate seam 21 with an approximately vertical side wall 22 extending round the toe region of the shoe. The front panel 20 with the integrally-adjoining tongue 17 consists of leather. The external rear part of the upper 11 is formed from synthetic plastics material or rubber. Figure 9 shows an inner liner 18 of leather or textile fabric extending over the whole upper, also an inner sole 19. The exterior side wall 22 is formed with the rear part 14 as an uninterrupted rubber or synthetic plastics material coating.

Figure 12 shows a sub-assembly comprising a leather upper exterior forward part 13 and an inner sole 19 of leather i.e. "breathing" material. In order to make a shoe the subassembly is drawn, for the production of the synthetic plastics parts, on to a last 23 of an injection-moulding or vulcanising apparatus.

As shown in Figure 12, there is an inner liner 18 which is of "breathing" material and extends only in the region of the synthetic plastics material rear part 14. The forward edges of the inner liner 18 are connected to the forward part 13 by a seam 24 binding the overlapping edges. Alternatively the said edges can also be stuck to the part 13 by adhesive. The inner sole 19 is connected to the inner liner 18 and to the forward part 13 by an oversewn seam 25 which renders it possible for the marginal portions which are to be mutually connected to be butted one to another as shown.

In making a shoe according to Figure 1 or 8 there may be used a sub-assembly which has an appearance somewhat as in Figure 12, while the forward part 13 is expediently secured on the continuous inner liner 18 by adhesion.

An apparatus or mould for use in the production or completion of the abovedescribed shoes can be formed in various manners. Each illustrated injection mould comprises a bottom plate 26, two lateral parts 27 and 28, preferably separated in the longitudinal central plane, and an insert piece 29.

A further bottom plate 30 can be exchanged with the bottom plate 26, for making a shoe with two different sole materials, namely the intermediate sole 12 with rear part 14 and an outer sole 10 or 31. The bottom plate 30 is provided with a mould cavity for the for mation of the intermediate sole 12, and the bottom plate 26 is provided with a mould cavity for the subsequently produced outer sole 31.

The lateral parts 27 and 28 in conjunction with the last 23 or the inner liner 18 on this last 23 form a mould cavity for the reception of the material for the synthetic plastics material parts, for example the rear part 14 including the lacing flaps 15. The insert piece 29 fits into a recess 32 of the lateral parts 27 and 28. The insert piece 29 isolates the parts of the upper 11 which consist of leather from the mould cavity for the parts of synthetic plastics material. For this purpose the insert piece 29 has a sealing lip 33 to engage the leather parts fixed on the last 23. Figure 3 shows a cross-section in the forward shoe zone where only the mould cavity for the intermediate sole 12 is to be limited upwards by the insert piece 29. In the region of the leather parts, that is the forward part 13, the insert piece 29 has a recess 34.

According to Figure 3 the sealing lip 33 extends, from the lower edge of the upper 11, along and near the edge of the leather forward part 13, into the region of the tongue 17.

Figures 2 to 7 and 9 to 11 show the tongue provided with a portion of the inner liner 18 on the inside. As may be seen for example from Figure 4, the inner liner 18 is initially continuous in the region of the tongue 17.

The lacing flaps 15 to be formed are also to be lined with portions of inner liner. For this purpose lining flaps 35 are sewn externally to the inner liner 18. The tongue 17 lies in the region of the recess 34 of the insert piece 29.

Downwardly-pointing legs of the insert piece 29 rest with the sealing lip 33 on the inner liner 18 so that in this region the inner liner 18 does not become coated with synthetic plastics material. After completion of the shoe this part of the liner between the tongue 17 and the inside of the lacing flaps 15 is cut so that the tongue 17 is free at its sides.

For good sealing of the mould cavities, both the inner liner 18 and the lining flaps 33 are prolonged (Figures 4, 5) beyond the respective mould cavities. The inner liner 18 and the lining flaps 35 lie with extensions 36 in the interstices between the lateral parts 27 and 28 and the insert piece 29 or the last 23 respectively.

The injection mould according to Figures 5 to 7 is likewise suitable for the production of shoes according to Figure 1, and has an insert piece 37 which is arranged only in the region of the tongue 17. The mould cavity for the reception of the intermediate sole 12 is limited by sealing lips 38, which are formed as parts of the lateral parts 27 and 28. The transition between the forward part 13 and the rear part 14 of the upper can be set back behind the region of the greatest width of the shoe.

The injection-moulding apparatus according to Figures 9 to 11 serves for the production or completion of shoes according to Figure 8.

Due to an insert piece 39-the forward panel 20 with the adjoining tongue 17 is isolated by a sealing lip 40. The lateral parts 27 and 28together with the bottom plate 30-form a continuous mould cavity for the reception both of the intermediate sole 12 and of all synthetic plastics material parts of the upper 11, that is not only in the region of the rear part 14, but also in the region of the side wall 22. As represented in Figure 9, the side wall 22 overlaps the bevelled edge of the front panel 20.

In order to achieve a good durable connection between the parts of leather and synthetic plastics material, inter-engagement can be effected between the said parts, as may be seen from Figure 13. The leather forward part 13 and the synthetic plastics material part 14 overlap one another with bevelled edges and the leather forward part 13 has holes 54. The synthetic plastics material of the part 14 penetrates into these holes 54 and forms pegs seated in them, and produces a secure connection of the said parts 13 and 14.

The holes 54 are formed in the region of the inner liner 18 so that the synthetic plastics material cannot penetrate to the last 23 of the mould.

Referring to Figures 9, 13 and 14, in the production of two-layer soles two injection passages 41 and 42 for two different materials, opening into the shoe toe, must be separated so that the successively injected materials do not mix with one another. For this purpose a two-part separator 43 separates the two injection passages 41 and 42 (Figure 9) and their respective connection passages 44 and 45 from one another. The upper injection passage 41 for the intermediate sole 12 and for the synthetic plastics parts of the upper 11 and the connection passage 44 extends above the separator 43, as recesses in the lateral parts 27 and 28 (Figure 10). The injection passage 42 for the outer sole 31 extends, with its connection passage 45, beneath the separator 43.

One cross-sectional half is formed in the bottom plate 26 and the other in the separator 43, but alternatively the connection passage can be formed as an upwardly open channel or groove completely in the bottom plate 26.

During the removal of the finished shoe from the mould the deadhead 46 formed by the injection passage 41 and connection passage 44 is free as soon as the lateral parts 27 and 28 are moved apart. In order that the shoe with the seconddeadhead47 in the region of the outer sole may be taken from the mould, the separator 43 is divided centrally into two halves 48 and 49 which are individually pivotable about respective spindles 50. For the withdrawal of the deadhead 47 the two halves 48 and 49 are pivoted about the spindles 50 and lifted to form an adequate gap. The halves 48 and 49 are welded to pivot arms 51 which are pivotably mounted on the spindles 50. Protruding ends of the pivot arms 51 act through presser pins 52 upon compression springs 53.The halves 48 and 49 are constantly loaded by these compression springs 53 in the direction towards the initial position as represented in Figure 15, so that after the removal of the deadhead 47 they return into this position.

In the illustrated apparatus any leather parts not to be coated with synthetic plastics material, that is for example the forward part 13 and the tongue 17 and the front panel 20, are isolated from the mould cavities for the reception of the synthetic plastics material by sealing lips of the lateral parts 27 and 28 and of the insert pieces 29, 37 and 39. In the region outside these sealing lips or edges there may be some space between the outer surfaces of the leather parts and the parts of the mould. Alternatively the relevant mould parts, namely the lateral parts 27 and 28 and the insert pieces, can engage full surface areas of the leather parts, for example with an elastic coating of polyurethane or silicone rubber.This elastic coating of the relevant mould parts, abutting against the full surface areas of the leather parts effects isolation of the coating-free leather parts from the mould cavities which receive the synthetic plastics material for forming other parts.

WHAT WE CLAIM IS:- 1. An injection mould for use in making a shoe (as hereinbefore defined) in which either or each of the sole (10) and the upper (11) comprises two or more parts (12, 31; 13, 14) made of different elastomers (as hereinbefore defined), the mould comprising at least one bottom plate (26, 30) and side parts (27, 28) and a last (23) and two separate injection passages (41, 42) for the injection in sequence of two different elastomers, characterised in that these injection passages (41, 42) are arranged with at least their outlets one above the other and these outlets are separated from each other by a separator (43) which extends between these outlets and is movable to facilitate the removal of deadheads from the liner one of said outlets.

2. A mould according to Claim 1, the said injection passages being for the injections of elastomers to form two parts (12, 31) of the sole, wherein the separator (43) is at the toe end of the mould.

3. A mould according to Claim 1 or 2, wherein the upper one (41) of the said injection passages extends at least partly in the region of the said side parts (27, 28) of the mould, and the lower one (42) of the said injection passages extends at least partly in the vicinity of a mould bottom plate (26).

4. A mould according to Claim 1, 2 or 3, wherein respective connection passages (44, 45) are also separated by the separator (43) and connect the said outlets to respective mould cavities.

5. A mould according to Claims 3 and 4, wherein a lower one (45) of the said connection passages is formed with its cross-section partly in the separator (43) and partly in the mould bottom plate (26).

6. A mould according to Claim 5, wherein the separator (43) consists of two movable halves (48, 49) which abut one another at a central vertical plane containing the axis of the lower one (45) of the said connection passages so that raising the said halves (48, 49) allows the removal of a deadhead (47) from this lower connection passage (45).

7. A mould according to Claim 6, wherein each of the said halves (48, 49) is mounted on a respective pivot arm (51) pivotable about a respective spindle (50) and loaded by a respective spring (53) towards the position of use.

8. A mould constructed and arranged substantially as hereinbefore described with reference to Figures 2 to 4, 5 to 7, 9 to 11, or 14 and 15 of the accompanying drawings.

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

Claims (8)

**WARNING** start of CLMS field may overlap end of DESC **. gap. The halves 48 and 49 are welded to pivot arms 51 which are pivotably mounted on the spindles 50. Protruding ends of the pivot arms 51 act through presser pins 52 upon compression springs 53. The halves 48 and 49 are constantly loaded by these compression springs 53 in the direction towards the initial position as represented in Figure 15, so that after the removal of the deadhead 47 they return into this position. In the illustrated apparatus any leather parts not to be coated with synthetic plastics material, that is for example the forward part 13 and the tongue 17 and the front panel 20, are isolated from the mould cavities for the reception of the synthetic plastics material by sealing lips of the lateral parts 27 and 28 and of the insert pieces 29, 37 and 39. In the region outside these sealing lips or edges there may be some space between the outer surfaces of the leather parts and the parts of the mould. Alternatively the relevant mould parts, namely the lateral parts 27 and 28 and the insert pieces, can engage full surface areas of the leather parts, for example with an elastic coating of polyurethane or silicone rubber.This elastic coating of the relevant mould parts, abutting against the full surface areas of the leather parts effects isolation of the coating-free leather parts from the mould cavities which receive the synthetic plastics material for forming other parts. WHAT WE CLAIM IS:-

1. An injection mould for use in making a shoe (as hereinbefore defined) in which either or each of the sole (10) and the upper (11) comprises two or more parts (12, 31; 13, 14) made of different elastomers (as hereinbefore defined), the mould comprising at least one bottom plate (26, 30) and side parts (27, 28) and a last (23) and two separate injection passages (41, 42) for the injection in sequence of two different elastomers, characterised in that these injection passages (41, 42) are arranged with at least their outlets one above the other and these outlets are separated from each other by a separator (43) which extends between these outlets and is movable to facilitate the removal of deadheads from the liner one of said outlets.

2. A mould according to Claim 1, the said injection passages being for the injections of elastomers to form two parts (12, 31) of the sole, wherein the separator (43) is at the toe end of the mould.

3. A mould according to Claim 1 or 2, wherein the upper one (41) of the said injection passages extends at least partly in the region of the said side parts (27, 28) of the mould, and the lower one (42) of the said injection passages extends at least partly in the vicinity of a mould bottom plate (26).

4. A mould according to Claim 1, 2 or 3, wherein respective connection passages (44, 45) are also separated by the separator (43) and connect the said outlets to respective mould cavities.

5. A mould according to Claims 3 and 4, wherein a lower one (45) of the said connection passages is formed with its cross-section partly in the separator (43) and partly in the mould bottom plate (26).

6. A mould according to Claim 5, wherein the separator (43) consists of two movable halves (48, 49) which abut one another at a central vertical plane containing the axis of the lower one (45) of the said connection passages so that raising the said halves (48, 49) allows the removal of a deadhead (47) from this lower connection passage (45).

7. A mould according to Claim 6, wherein each of the said halves (48, 49) is mounted on a respective pivot arm (51) pivotable about a respective spindle (50) and loaded by a respective spring (53) towards the position of use.

8. A mould constructed and arranged substantially as hereinbefore described with reference to Figures 2 to 4, 5 to 7, 9 to 11, or 14 and 15 of the accompanying drawings.