US2706351A

US2706351A - Safety shoe having a metal toe box with an impregnated fabric and vinyl lining

Info

Publication number: US2706351A
Application number: US445678A
Authority: US
Inventors: Wirt G Greenan
Original assignee: Safety Box Toe Co
Current assignee: Safety Box Toe Co
Priority date: 1954-07-26
Filing date: 1954-07-26
Publication date: 1955-04-19
Anticipated expiration: 1972-04-19

Description

Aprll 1955 w. G. GREENAN SAFETY SHOE HAVING A METAL TOE BOX WITH AN IMPREGNATED FABRIC AND VINYL LINING Filed July 26, 1954 M m m m United States Patent SAFETY SHOE HAVING A METAL TOE BOX WITH AN IMPREGNATED FABRIC AND VINYL LINING Wirt G. Greenan, Melrose, Mass., assignor to Safety Box Toe Company, Boston, Mass., a corporation of Massachusetts Application July 26, 1954, Serial No. 445,678

1 Claim. (Cl. 36-77) This invention comprises a new and improved shoe construction for safety shoes embodying a steel toe box such as that described in United States Patent No. 2,457,664, Harrison.

It is of course important to protect the foot of the wearer from contact with the metal of the box, and highly desirable to seal the box from perspiration from the foot which would otherwise cause rusting. Many attempts have been made to secure a lining to the inner surface of the metal box, but these have not been successful and accordingly a serious objection to safety shoes has been that the lining inside the steel box has had a tendency to drop down and away from it to the great discomfort of the wearer.

I have solved this long standing problem by providing a novel lining having a toe portion of felt impregnated with a thermoplastic stiffening compound, the impregnated portion of the lining being conformed and adhesively bonded to the inner concave face of the metallic box and retaining its conformed shape in the shoe by reason of its thermoplastic stiffening compound rather than by adhesion. The impregnated portion of the lining presents a smooth moisture-proof facing next the foot of the wearer. This may comprise a vinyl film or sheet, and while this material has a tendency to return to its normal fiat condition, in accordance with the present invention it is maintained in the shape imparted to it by the last by its association with the impregnated and molded portion of the lining.

These and other features of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof, selected for purposes of illustration and shown in the accompanying drawings in which:

Fig. 1 is a view in perspective showing the forepart of a partially lasted shoe with the toe portion of the lining conformed to the last,

Fig. 2 is a similar view showing the steel box in place upon the conformed lining, and

Fig. 3 is a plan view of the lining.

The lining as herein shown includes a textile ply of drilling or the like and a felt ply 11 to one surface of which is firmly bonded a vinyl film or sheet 12. In Fig. 3 a portion of the vinyl sheet is shown as forcibly separated from the felt ply 11 which is folded so as to expose a portion of the former. The felt ply is shaped to cover the toe portion of the last and is impregnated with a thermoplastic stiffening medium. One satisfactory compound consists of approximately 130 parts rubber, 400 parts resin-containing box toe scrap, 100 parts cumarone resin, and 200 parts asbestos fiber. Another satisfactory stiffening compound includes rubber, wax, colophony and, as a dominant ingredient, cumarone indene resin. The stiffening compounds mentioned are typical of an assortment of compounds which have been found satisfactory in the shoemaking industry and which are entirely suitable for purposes of the present invention.

The vinyl film or sheet 12 is readily obtainable in the market and may be united permanently to the felt ply 11 2,706,351 Patented Apr. 19, 1955 by heat and pressure. As herein shown the combined felt and vinyl plies are secured to the textile portion 10 of the lining by a stitch line 13. While the lining herein shown is of full length, it will be understood that it would be within the scope of the invention to assemble the combined felt and vinyl plies as part of a cut-off vamp lining.

The lining of my invention may be incorporated in the upper of a safety shoe by the conventional steps of shoemaking. For example, as shown in Fig. l the lining is incorporated in an upper which comprises a leather vamp 14 to which the quarters are stitched in the usual manner. A ribbed insole 15 is tacked to the bottom of the last, the toe portion of the lining is heated to render it soft and flexible in the usual manner, and then lasted about the forepart of the last and stapled to the rib of the insole 15 while the vamp 14 is turned back out of the way. In the lasting operation the lining is conformed accurately while hot and flexible to the toe portion of the last. In cooling it stiffens and is thus set in the exact convex shape of the toe of the last.

This is the condition of the partially completed shoe as shown in Fig. l. The molded lining retains its toe shape by reason of its stiffening impregnant without any tendency to loosen or leave the contour of the last and so interfere with the presentation of the steel box toe. The thickness of the toe lining is uniform throughout and of just the proper thickness to receive the steel box with a high degree of accuracy. The vinyl film is located next to the last and will lie next to the wearers foot in the finished shoe. The marginal edges of the lining are permanently lasted to the upstanding rib of the insole.

The steel box 16 is next placed upon the toe of the last enclosing the conformed lining therein, and since the steel box has been specially shaped to fit the lined toe of that particular last the steel box can assume only the correct position in the upper. Subsequently the vamp 14 itself is lasted over the steel box and secured to the rib of the insole.

It will be seen by the process above described that the toe portion of the lining is permanently maintained by being stiffened in situ in the exact shape of the toe of the last, and its shape is not dependent upon adhesion to the box. In the finished shoe the conformed lining is firmly attached at its margins to the insole rib and not only maintains its own shape but tends to hold adjacent parts of the shoe structure in the desired position.

While felt is preferred as material for the toe portion of the lining any other equivalent bibulous fabric may be employed if desired.

Having thus disclosed my invention and described in detail a preferred embodiment thereof I claim as new and desire to secure by Letters Patent:

An improved safety shoe including in the structure of its forepart a metallic box toe concealed within the outer integument of the upper, and a lining having a toe portion of felt impregnated with a thermoplastic stiffening compound, the impregnated toe portion of the lining being lasted about its marginal edges, conformed to the inner concave face of the metallic box and retained in its conformed shape in the upper by reason of its thermoplastic stiffening impregnant, and a moisture-resistant vinyl film adhesively bonded to the inner face of the felt of the said toe portion, exposed inside the upper next the foot of the wearer and retained in its conformed shape by its bond to the stiffened felt of the said toe portion.

References Cited in the file of this patent UNITED STATES PATENTS 1,826,645 Berquist Oct. 6, 1931 2,584,516 Veatch Feb. 5, 1952 2,618,796 Brophy Nov. 25, 1952