US3444572A

US3444572A - Safety footwear

Info

Publication number: US3444572A
Application number: US521584A
Authority: US
Inventors: Geoffrey Broughton
Original assignee: Betts and Broughton Ltd
Current assignee: Betts and Broughton Ltd
Priority date: 1966-01-19
Filing date: 1966-01-19
Publication date: 1969-05-20
Anticipated expiration: 1986-05-20

Description

May 20, 1969 G. BRouGHToN 3,444,572

SAFETY FOOTWEAR Filed Jan. 19, 1966 mvmon @fof-ferr @Re uom-0N BY M1 /''roRNEY United States Patent O 3,444,572 SAFETY FOOTWEAR Geoffrey Broughton, Sutton-in-Ashfeld, England, assignor to Betts and Broughton Limited Filed Jan. 19, 1966, Ser. No. 521, 584 Int. Cl. A43d 11/12 U.S. Cl. 12-142 3 Claims ABSTRACT OF THE DISCLOSURE The invention relates to safety footwear having a metal toe cap which is covered to provide added reinforcement and to eliminate the danger of sparks. The footwear includes a sole of synthetic resin, and a seamless molded outer cap integral with the sole and covering the metal toe cap. The resin outer cap is bonded to the metal toe cap. The upper, or a liner, extends inwardly of the metal toe cap.

This invention concerns safety footwear (i.e. boots, shoes and the like) having a protective metal toe cap. Safety boots of this type are commonly worn by miners, quarry men, and industrial workers. Usually the metal toe cap in safety boots for miners and quarry men, is exposed at the exterior of the boot or the like. This has the disadvantage that it is liable to give rise to sparks if struck or scraped.

An object of this invention is a construction in which this disadvantage is eliminated and at the same time the metal toe cap is given additional reinforcement so that its crushing strength is enhanced.

'The invention therefore provides an article of safety footwear having `a sole of moulded synthetic resin and a seamless moulded outer cap integral with the sole and covering the metal toe cap. This outer cap shields the metal toe cap and obviates the `danger of sparking and it enhances the crushing strength. Desirably the metal toe cap has an inner lining (e.g. of fabric or leather) which is lasted over an insole. This inner lining acts as a protection to the wearers toes against chai-ring or the like.

Two alternative constructions are within the scope of this invention as above dened. In one construction the metal toe cap is applied exteriorly of the toe portion of the upper material, which therefore provides the said inner lining. This construction may permit the upper to be void of a lining, and so permits of economy in lining material. In the other, the toe portion of the upper material is omitted except for a liner (e.g. of fabric or leather) for a substantial part of the zone occupied by the metal toe cap. It will be understood in both of these alternative constructions the molded cap is incorporated. The second construction has the advantage of economy in upper material. Both constructions permit a toe puff to be dispensed with.

In order that the invention may be better understood two such constructions Will now be described in greater detail with reference to the accompanying drawings, in which:

FIGURE l is a sectional view of the basic toe construction according to this invention;

FIGURE 2 is a sectional view of the toe portion of an embodiment;

FIGURE 3 is a sectional view of the toe portion of a second embodiment;

FIGURE 4 is a sectional view of the toe portion of a third embodiment.

Like parts are identified by like numbers in the drawings. In FIGURE 1, the sole of the shoe, boot or the like is indicated at 1 and is integral with an outer cap 2 the sole 1 and cap 2 being formed of synthetic resin. A metal ICC toe cap 3 is bonded to the outer cap 2 and is provided with an inwardly-turned ange 4 around the lower margin thereof which margin is located below the insole 5 of the shoe, boot or the like. A lining 6 is preferably bonded to the inner surface of the metal top cap.

In the construction shown in FIGURE 2, an upper 7 comprising a leather outer layer (but without any liner) is lasted over an insole 5 in the usual manner. The lasting margin 8 of the upper, and the outer surface of the toe area (extending for a short distance rearwards of the location to be occupied by the metal toe cap) are roughened and a suitable adhesive applied thereto. A metal toe cap 3' having its lower margin 4 turned inwards as a ange is then applied exteriorily to this lasted component, with the ange 4 below the insole 5. If desired a piece of fibre board 9 or like relatively rigid material having the plan form of the metal toe cap is then applied beneath the turned-in flange so as to provide, in the finished boot or the like, a firm foundation for the metal toe cap as shown in FIGURE 3. The lasted component is then inserted into a mould in an injection moulding machine by which a sole and heel shown generally at 1 of a suitable synthetic resin, and an integral seamless moulded outer toe cap 2 which covers and adheres to the exterior of the metal toe cap, are moulded onto the component. This moulded outer cap 2 extends slightly rearwards of the metal cap 3 and adheres to the material of the vamp. This rearwards extension avoids an abrupt transition between the rigid metal toe cap `and the flexible vamp.

Desirably the component, and its mould, is then transferred to a second station in the injection moulding machine where the base of the mould is lowered and further injection takes place to apply a wearing surface 10 of synthetic resin of a softer character but higher quality than the lirst to the sole and heel (see FIGURE 3). This wearing surface may be appropriately formed (for example, ribbed) to give a good grip.

1t is desirable that around the toe of the sole the first sole layer of harder material shall -be given a downwardly protruding wall 11 which protects the toe end of the second and softer sole layer.

'Since the moulded cap continues rearwardly of the rear edge of the metal toe cap so as to overlap and adhere to the outer surface of the vamp, the required area of the vamp should be suitably treated to produce a good bond between it and the synthetic resin, for which purpose it may be roughened and/or coated with a bonding agent. For like reasons the outer surface of the metal toe cut cap may be cleansed and given a matt surface by sand blasting or shot blasting and may be treated with the bonding agent.

In an alternative construction shown in FIGURE 4, the toe portion of the upper s omitted except for a liner 12 (of fabric or leather), so that the main part of the vamp terminates just rearwards of the line to be occupied by the rear end of the metal toe cap. The forward margin of the vamp is preferably skived or of reduced thickness.

The upper, together with the toe portion of the liner, is lasted over the insole as before described, the metal toe cap 3 is applied so that its rear margin abuts against or is slightly spaced from the forward marginal part of the vamp, and the fibre board or other foundation may be applied beneath the metal toe cap as in the embodiment shown in FIGURE 3, the lasted component then being treated in the injection moulding machine in the manner previously described. Again it will be `understood that the rear marginal part of the moulded outer cap extends slightly rearwards of the rear edge of the metal toe cap and is adhered to the material of the vamp. If the rear margin of the metal toe cap is spaced from the forward end of the vamp, the synthetic resin lls the gap and produces a level surface between the inner surfaces of the vamp and toe cap, thus making for comfort in wear.

In each of the foregoing constructions, the moulded outer cap is resistant to abrasive wear.

The two sole layers 1 and 10, while being of the same basic material may differ in colour or shade.

I claim:

1. The method of manufacturing an article of safety fooweart in the mould of an injection molding machine which comprises lasting an upper over an insole, applying an adhesive to the outer surface of the lasted margin in the upper and outer surface of the top portion thereof, applying a metal top cap exteriorly of the lasted toe p0rtion of the upper, inserting the lasted upper, insole and metal top cap into a mold of the injection mold machine and molding one piece sole, heel, and an integral seamless molded outer toe cap of snythetic resin, completely overlying the metal toe cap, the sole and heel bonding directly to the lasting margins, the toe cap being formed in situ and bonded to the metal toe cap throughout the entire outer surface of the metal toe cap during the molding operation.

2. The method of claim 1 and including a reinforcing member of rigid material having the plan form of 25 the metal toe cap and including the step of applying the reinforcing member beneath the toe cap to provide a rm foundation for the metal toe cap.

3. The method of claim 1 and including the step of applying a second sole of synthetic resin beneath the rst sole, resin forming the second sole being of a resin softer and of higher quality than is used in forming the rst named sole.

References Cited UNITED STATES PATENTS 73,924l 1/1868 Pickett 36-32 X 1,507,844 9/1924 Mason 36-32 X 2,426,211 8/ 1947 Heckman 36-4 FOREIGN PATENTS 1,222,771 1/1960 France. 1,392,836 2/ 1965 France.

863,944 3/1961 Great Britain.

OTHER REFERENCES Plastic Catalog, 1942, p. 562, Plastic Cataloque Corp.

ALFRED R. GUEST, Primary Examiner.

U.S. Cl. X.R. 36-32, 77