US 2795868 A
Description (OCR text may contain errors)
June 18, 1957 Filed Nov. 15, 1955 United States Patent LINER FOR METAL T OE BOXES Edward L. Shultz, Endicott, N. Y., assignor to Endicott Johnson Corporation, Endicott, N. Y., a corporation of New York 2 Application November 15, 1955, Serial No. 546,843
3 Claims. (Cl. 36-77) This invention relates to an improved liner for safety toes used in safety footwear.
Safety footwear is worn for the protection of feet under hazardous conditions where falling articles, vehicles or the like might cause injury to the feet of the wearer. Safety footwear generally includes a steel toe located inside the tip of the shoe. The steel toe is in the form of a concavo-convex steel box lying underneath the tip and extending to the sole along the lateral and front edges of the box and terminating approximately at the end of the tip. A liner is provided beneath the steel toe box of safety shoes and my i nven-' tion has for its object the provision of an improved liner and an improved combined safety toe box and liner for use in safety footwear.
Prior to the development of the safety toeliner disclosed in my copending patent application Serial No. 406,751 filed January 28, 1954 which has matured into Patent No. 2,740,208 granted April 3, 1956, the safety toe liners which were in commercial use were unsatisfactory and presented a number of problems to the shoe industry. The invention of my aforesaid patent application solved the problems encountered in the industry by providing a safety toe liner made of a film of a suitable plastic such as polyethylene arranged in concavoconvex shape to conform to the contour of the under- Surface of the toe box and having a transverse marginal area extending across its trailing end defined by an upstanding forwardly facing shoulder which engages against the trailing end of the toe box so that the toe box and the marginal area of the liner presents a smooth, continuous upper surface.
It is an object of the present invention to provide an improved safety toe liner of this general type having the added advantages that the body of the liner fits tightly against and as a matter of fact is urged into en- I gagement with the inner surface thereof and also the trailing marginal portion is urged upwardly and outwardly into engagement with the shoe upper or lining eliminating any gap between the liner and upper.
A further object of the invention is the provision of an improved safety toe liner of the above type which is inexpensive to manufacture and can be produced in finished form by a simple molding operation; which will simplify the production of'safety shoes; which will effectively protect the feet of the wearer from the metallic toe box; which will enhance the appearance of safety shoes and also protect the shoe upper from the wearing or cutting action of the toe box; and which will profeet the metallic toe box from corrosion inducing perspiration. v
My invention contemplates the provision of a safety it ice is assembled with the shoe it is urged into engagement with the shoe upper or lining thereby preventing any gap between the trailing end of the safety toe liner and the shoe upper.
In the accompanying drawings- Fig. 1 is a perspective view of a metallic safety toe and of a safety toe liner embodying my invention shown in separate unassembled form;
Fig. 2 is a partially sectional view in elevation of the toe and adjacent portions of a safety shoe incorporating a safety toe and a safety toe liner embodying my invention;
Fig. 3 is a top plan view of the safety toe liner; 7
Fig. 4 is a longitudinal sectional view of the liner in the direction of the arrows on the line 4--4 of Fig. 3;
Fig. 5 is a similar view but showing the safety toe liner assembled with the safety toe; and
Fig. 6 is a transverse sectional view showing the liner in unassembled form in full lines and indicating a com parable section of the safety toe with which it is to be assembled in dotted lines showing the differences in dimensions between the unassembled liner and the safety toe.
My improved safety toe liner is applicable to any type of safety footwear and is not limited to any specific design or type of shoe. In addition, it is applicable to shoes made by the Goodyear Welt process or by the McKay process or by any other process. For purposes.
of illustration, my invention is illustrated as applied to a safety toe liner incorporated in a shoe made by the Goodyear Welt process but this should not be construed as limiting my invention to shoes of this type.
In the drawing I have shown one conventional type of safety toe 10 which is in the form of a concavo-convex dome-shaped box having integral depending side and front walls which are also concave-convex and which is open at its trailing end as shown. The safety toe is made of suitable strong material which can withstand considerable loads, impacts or forces and for this purpose I prefer to use a suitable metal such as steel.
My improved liner is illustrated generally at 12 and it is formed of a film of a suitable flexible, resilient plastic so that it will conform to the inner surface ofthe safety toe when stressed as hereinafter described. In addition, the material should be tough and strong so as to withstand wear; it should be impervious to and unaffected by perspiration and moisture and it should present a smooth yielding surface so as to be comfortable to the wearer. For this purpose, I have found that various plastic materials such as polyvinyl chloride and molded rubber compositions may be employed but I prefer to employ solid polymerized polyethylene. Any solid polymerized polyethylene that can be molded can be used but I prefer to employ polyethylenepolymers having a melt viscosity at C. of between 5x10 and 22x10* poises which corresponds to a melt index of between 200 and 0.33 (American Society of Testing Materials Bulletin ASTM Designation D1238-52T, issued 1952). By making the liner of polyethylene the additional advantage is obtained that it may be molded by injection molding in one piece in complete form ready for use.
The liner has a concavo-convex portion 14 which has downwardly depending side and forward walls formed integrally therewith and which likewise are of concavoconvex shape.
The surface area of the body portion of the liner corresponds generally with the inner surface area of the safety toe. In unstressed condition, however, the dimension of the body portion of the liner in one direction is a little larger, and the dimension in another direction is a little smaller than the corresponding'dimensions of the safety :toeQ Thus, as I have shown most clearly in Fig. 6, the width of the liner 14 is preferably a little greater than the width of-the metal toe cap and the height is a little smaller than the height of the metal toe cap. As a result, when the liner is assembled inside the toe cap, the liner will be stressed laterally causing it to flex upwardly and to be urged into intimate contact with the inner surface of the safety toe, as shown in Figs. 2 .and 5. This action results from the fact .that the liner is made of a flexible resilient material as stated above.
The trailing end of the liner is provided with 'a transverse marginal strip. portion 16 which is defined by a forwardly projecting shoulder 17 arranged to engage against the trailing edge of the toe cap when the liner is assembled with the toecap. The height of the shoulder 17 is such that when the liner and toe cap are assembled together the outer surface of the marginal portion 16 will be flush with the outer surface of the toe cap, as most clearly shown in Figs. 2 and 5.
V The marginal portion 16 tapers in thickness from the shoulder 17 to the trailing edge 18 which is preferably in the form of a fine, feathered edge. In addition, the marginal portion flares upwardly and outwardly from the shoulder to the trading edge 18 so that when it is assembled in a shoe the trailing edge will be urged upwardly and outwardly into intimate engagement with the shoe upper or lining 'asshown in Fig. 2 thereby eliminating any space or gap between the trailing end of the liner and the shoe upper or lining.
Extending'around the lower edge of the safety toe liner is the inwardly projecting seat or flange 20 having the downwardly projecting attaching flange 22 secured thereto. The attaching flange 22 is provided where the shoes are manufactured in accordance with the Goodyear Welt process and the attaching flange is secured to the welt rib. Where the shoe is made by the McKay process, no such attaching flange is required on the liner.
A safety shoe incorporating a safety toe and my improved safety toe liner may be manufactured in accordance with standard shoe manufacturing proceedings and many of the steps heretofore required in the manufacture of safety shoes may be eliminated.
In Fig. 2, I have shown the toe portion of one type of shoe having an upper 24, an outer sole 25, an inner sole 26 and suitable filler material 27 filling the space between the inner sole and the outer sole. The shoe construction illustrated is of the Goodyear Welt type and the inner sole 26 is provided with a welt rib 28 to which the upper and the attaching flange of the safety toe liner are attached by a line of stitching.
' In the illustrated shoe the safety toe is shown inside the toe in directcontact with the upper. However, it should be understood that one or more layers of lining may be positioned between the upper and the safety toe and safety toe liner, and where I state herein that the trailing edge of the liner is urged into contact with the upper it should be understood that this expression also includes a lining for the upper where such a lining is employed. The safety toe liner 12 is assembled inside the safety toe and as previously described is stressed laterally and is thereby urged into intimate contact with the inner surface of the safety toe as clearly shown in Figs. 2 and 5. Due to the fact that the marginal portion 16 at the projecting trailing end of the liner flares upwardly and outwardly, the trailing edge is urged upwardly and outwardly as shown in Fig. 5 and when assembled in a shoe the trailing edge is urged into intimate contact with the shoe upper or lining, as clearly shown in Fig. 2.
If desired, the liner 12 may be cemented to the safety toe and the marginal portion thereof maybe cemented to the upper or to the upper lining and for this purpose I employ a suitable adhesive for polyethylene such as an emulsion type cement consisting of a reclaimed rubber dispersion modified with resins.
It will thus be seen that I have provided an improved safety toe liner for use in safety shoes in which the liner, when assembled with the safety toe, is stressed into intimate contact with. the inner surface thereof and in which the trailing edge of the liner is urged upwardly and outwardly into intimate contact with the shoe upper or the upper lining. It will also be seen that my improved liner may be inexpensively manufactured by a simple molding operation; that it may be assembled in the shoe by means of simple and conventional shoe manufacturing operations; that is cflmfortable to the wearer and protects both the foot of the wearer and the shoe upper from the edges of the safety toe; and thatit provides a safety shoe of attractive appearance without any of the unsightly ridges or creases, frequentlyassociated with safety shoes.
Modificationsmay be made in the illustrated and described embodiment of my invention without departing from the invention as set forth in the accompanying claims. v p
1. In a safety shoe the improved, combination of a safety toe and liner which comprises: ametallic concavoconvex dome-shaped box having downwardly depending lateraland forward edges and an open trailing edge, and a concave-convex dome-shaped liner made of a film of resilient, flexible but tough plastic material and having downwardly depending lateral and forward edges and an open trailing edge said liner being disposed inside said metallic boxin engagement with the inner surface thereof and being stressed laterally in compression by the side walls of the box so that the central portion of the liner is urged upwardly and the entire liner is held in intimate frictional engagement with the undersurface of the box.
2. In a safety shoe the improved combination of a safety toe and liner as set forth in claim 1 in which the plastic material is solid polymerized polyethylene.
3. In a safety shoe the improved combination of a safety toe and liner as set forth in claim 1 in which said liner has a transverse marginal portion at its trailing end extending beyond the trailing end of the box and defined by a forwardly projecting shoulder in engagement with the trailing edge of the box said marginal portion being tapered from the shoulder to its trailing edge and being arranged to flare forwardly and outwardly so as to urge said trailing edge upwardly and outwardly.
References Cited in the file of this patent UNITED STATES PATENTS 288,944 Joyce Nov. 20, 1883 2,457,664 Harrison Dec. 28, 1948 2,537,891 Greenan Jan. 9, 1951 2,584,516 Veatch Feb. 5, 1952 2,720,042 March June 17, 1954 2,740,209 Shultz Apr. 3, 1956 FOREIGN PATENTS 134,039 Australia Aug. 29, 1940 1,009,037 France Feb. 27, 1952