US2114708A - Means for manufacturing footwear - Google Patents

Description

Patented Apr. 19, 1938 UNITED STATES PATENT OFFECE David Gordon Gash, Balaclava, Victoria, Australia Application April 23, 1936, Serial No. 75,997 In Australia April 26, 1935 2 Claims.

This invention has reference to a method of and means for manufacturing footwear and has been devised to provide footwear which is moulded in lieu of being constructed in various parts 5 to form the completed shape.

It has been the .accepted practice in the manufacture of footwear particularly when moulding rubber or like resilient shoes or boots to form the same in various sections which are united by cementing together both the parts to be conjoined and the lining of canvas or the like which necessitated costly and tedious operations while in the finished product the parts had a tendency to disunite more particularly the sole from the upper canvas.

The main object of the present invention is to provide a method of manufacturing footwear particularly rubber boots and shoes in one complete unitary structure and wherein the above disadvantages and defects are obviated, the nished article being of the necessary resiliency and having the quality and durability to withstand normal use without becoming misshapen, which is a detrimental feature of leather footwear, while the normal shape of the shoe or boot conforms to the shape of the foot when removed therefrom.

With the above object in view the present in* vention consists in moulding footwear in one complete structure and wherein the last or core which is of a standard shape is rstly coated with uncured rubber after which the sole and heel portion is shaped on the last by pressure whereby the form may be cooked in a vulcanizer with the resultant moulded product being a boo-t or shoe formed in one complete unit of the desired shape and size.

An important feature embodied in my invention is that during the application of the uncured rubber to thel last or core it may be suitably coloured and shaped to a desired configuration, while the sole and heel may be constructed of rubber having less resiliency or elasticity than the material employed for the upper.

Another important feature embodied in my invention is the provision of means for moulding a shoe or boot by the method described and by the employment of said means moulding the said footwear in one complete structure of a desired shape the means preferably comprising a mould constructed in two correspondingly shaped sections between which may seat a last or core of selected size while a selected pressure plate is associated with said sections to seat therebetween and over the base of the last or core whereby .after the rubber or material is coated on said (C1. liti- 42) last the closure of the sections under pressure effects a positive conforming of the unvulcanized rubber to the shape of the last and selected pressure sole and heel plate to bring the moulded shoe or boot to the condition of being cooked in a vulcanizer or other practical apparatus.

A further important feature embodied in the invention is that the soles .and heels are composed of a rubber having a substantially harder composition than that of the upper while the sole may have formed thereon a tread of desired configuration.

The invention will be hereinafter more particularly described with reference to the accompanying drawing showing a mould for carrying out the method according to the invention and in which:-

Figure 1 is a plan view of one section of the mould having the core and sole pressure plate positioned therein.

Figure 2 is a plan view of the co-acting section of the mould.

Figure 3 is a sectional elevation of the assembled mould sections with the core and sole pressure plate in position.

Figure 4 is an elevation of the core or last of the mould. I

Figure 5 is a sectional elevation through line 5 5 of Figure 4.

Figure 6 is an elevation of the sole and heel pressure plate.

Figure 7 is a sectional elevation through line 'l-I of Figure 6.

According to one form of carrying my invention into practical effect with the method pre# viously described I provide a lnould comprising two co-acting sections IIJ each section being hollowed to form `a recess II therein adapted to receive with a predetermined clearance one side or portion of a correspondingly shaped last or core I 2 which conforms to a standard shape. Formed adjacent the base of the recess II in each sec.- tion IIJ is an extended recess I3 adapted to receive a sole and heel pressure plate I4 this latter recess I3 being slightly deeper than the recess II shaped to receive the last I2 for the purpose of providing a welt on the moulded shoe or boot.

The back of the pressure plate I4 for forming the sole and heel is formed With oppositely disposed tapered cam surfaces I5 extending outwardly from each edge and converging in the approximate centre of said plate I4, correspondingly tapered cam surfaces I5 being provided on the adjacent edges of the moulding sections IU. Such tapered surfaces I5 and I6 are for the pur- Vso pose of facilitating the entry of the pressure plate M when the last i2 is in position and is coated with uncured rubber ll the said pressure plate Iii being forced in a direction parallel to the interface between the sections into correct position when the two sections Ill of the mould are assembled.

In order to prevent the last I2 from being forced out of position when the sections I of the mould are being assembled I provide one or more keyways or grooves I8 on the upper or positioning portion of the last i2 which keyways i8 are adapted to engage with projecting keys or ridges i9 formed on the mould section lo. The kcyways i3 and keys i9 are preferably made with inter-fitting inclined cam faces so as to guide the core into its proper position when the mould sections are moved together to close the mould. The core is then held firmly in its proper position by interengagement of 'the cam faces of the keys and keyways until the mould is opened.

Conveniently positioned on the adjacent faces of the co-acting sections ill of the mould I provide small channels 2l) which extend to the edge of the mould sections I] these channels 28 being for the purpose of permitting the discharge of excess material that is forced from the mould during operation.

A separate mould may be made for each last l2 with pressure plate ld but it is preferable to incorporate a pair of right and left lasts I2 and pressure plates M in the one section l0 as illustrated in the accompanying drawing.

In building up a last I2 the said last I2 is removed from divided sections i@ of the mould and coated with a layer of uncured rubber I1 of predetermined thickness; any portion of the coating of rubber may be suitably covered or have a pattern imparted thereto, a coating of rubber of harder composition if desired being applied to the sole of the last I2 for the purpose of forming the sole and heel of the boot or shoe. The last I2 is then placed in position in one of the correspondingly shaped recesses i I formed on each internal side of the co-acting sections IE of the mould.

The pressure plate I4 is then inserted into the mould section I5) carrying the last l2, in the recess I3 directly below the bottom of the last i2 but owing to the thickness of the uncured rubber Il this pressure plate Iii is prevented from being correctly positioned without pressure being applied thereto, but due to the taper I6 on the back face of the pressure plate ifi the entry of said plate Iii into the mould section Il is made possible. The interaction between the inclined faces It of the mould on the inclined faces I5 on the pressure plate forces the pressure plate toward the core member I2 as the mould sections move toward each other until the pressure plate occupies its correct position within the cavity of the mould.

The surface of the heel and sole plate I4 adjacent the bottom of the last I2 may beof desired formation according to requirements and may have formed thereon projections 2l or the like for imparting a desired tread on the sole of the inished product.

Should it be desired the heel section 22 of uncured rubber El may be stamped out and placed adjacent the heel of the last i2 prior to the insertion of the heel pressure plate Ill and reinforcing fabric (not shown) is incorporated with the uncured rubber lll forming the upper of the shoe in order to prevent fracture of the rubber at a position where eyelets (not shown) are inserted after the product has been vulcanized.

The effective surface or recess II of the mould section Iii may be provided with projections or indentations 23 in order to impart to the exterior of the shoe a desired pattern or configuration and similarly the last l2 may be provided with indentations 24 on the back of the heel in order that the interior of the moulded product may have gripping means formed thereon such as a plurality of spaced projections.

With the last I2 having the coating of uncured rubber Il of suitable composition and uncured hardened sole and heel applied thereto in the operative position and the pressure plate I4 inserted into the section IU of the mould, the coacting section Ii! of the mould is then placed in position and pressure applied thereto thereby forcing the sole and heel pressure plate I4 downwardly and at the same time inwardly against the sole of the last i2. While the co-acting sections I0 of the mould are held together under pressure suitable fastening means associated with said sections iii are brought into operation, the said fastening means preferably comprising a pivotal bolt 25 adapted to engage projecting lugs 26 on the opposite section I of the mould. The mould is then placed in a suitable vulcanizer (not shown) for a period sulicient to cook the uncured rubber Il after which the mould is removed and opened, and the core or last I2 removed from the vulcanized rubber shoe or boot as the case may be.

The shoe is then dressed and prepared to remove any excess material formed at the joint of the mould sections i@ and suitable eyelets (not shown) incorporated in the front of the shoe for lacing purposes, the tongue (not shown) of the shoe being inserted and fixed to the upper by the lower eyelets.

In order to obtain a predetermined thickness of the sole of the shoe varying sized pressure sole plates I4 are provided for the purpose. DoWel pins 2l and co-acting dowel openings 28 are also provided on the mould sections IB to ensure correct alignment.

It will be understood that the product obtained by the method herein described has the natural appearance of a standard shaped last and from appearance is identical with a leather shoe having a Welted sole thereon.

What I claim as my invention and desire to secure by Letters Patent is:- p

1. A mould for forming one-piece rubber shoes, which comprises a pair of mould sections having recesses therein cooperating to form a cavity when the mould is closed and having core positioning portions, and a unitary core member having a core portion in the shape of a shoe last adapted to be spaced from both mould sections when in position in the closed mould and a positioning portion integral with said core portion, said corepositioning portions of both the core member and the mould sections comprising intertting ridges and grooves with inclined cam faces adapted to move said core portion into proper position relative to the mould sections when the mould sections are moved together to close the mould.

2. A mould for forming one-piece rubber shoes, which comprises a pair of mould sections having recesses therein cooperating to form a cavity when the mould is closed and having core positioning portions, a unitary core member having a core portion in the shape of a shoe last adapted to be spaced from both mould sections when in tions are moved together to close the mould, and eJ sole pressure plate in said cavity opposite the bottom of said core, said sole pressure plate and mould sections having coasting cam faces to force said plate toward said core when the mould 5 sections are moved together to close the mould.

DAVID GORDON GASH.

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