US1721599A - Rubber heel - Google Patents

Description

.My 23, 19290 E. lKROEGER RUBBER HEEL Filed Sept. 9, 1926 INVENTOR. Ea n W JE/m firvozam A TTORNE.

Patented July 23, 1929.

UNITED STATES PATENT OFFICE.

EDWIN JOHN KROEGEB, 0F AKRON. OHIO, ASSIGNOB TO JOHN B. GAMMETER, OF

AKRON, OHIO.

RUBBER HEEL.

Application flled September 9, 1926. Serial No. 134.350.

This invention relates to rubber heels and methods for producing the same.

The general purpose of the invent-ion'is to provide a rubber heel construction with an insert through which nails can be driven any where and which will effectively prevent the heel from working off the nails, thus obviating forming heels with nail holes and using metal reenforcements, such as washers or the like, about the nail holes.

Particularly, one object of the invention is to provide a light, inexpensive, highly resilient rubber heel of absolutely waterproof construction, including an insert of hard cellular rubber, such as vulcanized, hard sponge rubber, which may be vulcanized in the heel without special treatment to produce an integral heel construction, the cellular structure of the insert being such that a nail penetrating certairicells will not collapse the walls of adjacent cells, so that the insert will not'split or crack.

Another object of the invention is to provide a rubber heel with a nail-receiving insert therein, both mechanically and chemically united withthe body of the heel.

Another. object of the invention is to provide aheel capable of being applied to footwear by automatic nailing machines.

Another object of the invention is to provide as an article of manufacture a rubber heel in which the nails have been started so that the cobbler need only apply the heel to the foot-wear and drive in the nails, handling of the nails thus being avoided;

Another object of the invention is to provide a method for producing the above heel. This method preferably comprises vulcanizingthe heel with the insert, said insert being either previously completely or partially vulcanized oi' compounded of rubber capable of vulcanizing during vulcanization of the heel, the heel being vulcanized under such pressure as to prevent distortion of the heel by expansion of the gases in the cellular insert.

The foregoing and other objects of the invention are obtained by the heel construction illustrated in the. accompanying drawings and described below. It is to be understood that the invention is not limited to the specific form thereof shown and described.

(ll the accompanying drawings:

Figure l is a bottom plan of a heel embodying the invention;

- Figure 2 is a top plan thereof;

Figure I is a section on line 3-3 of Figure 1;

Figure 4 is a section on line 4-4 of Figure 2; and

Figure 5 is a perspective view of the heel illustrated with the nails started, in which form the heels may be supplied by manufacturers.

Referring to the drawings, the numeral 10 designates the body portion of the heel which is of soft, tough rubber of the usual compositions such as heretofore have been employed.

During the process of vulcanization of the heel 10 an insert 11, preferably of an outline similar to that of the heel, is embedded in the top thereof, this insert preferably being formed of such material as vulcanized, hard sponge rubber either previously partly or wholly vulcanized or compounded rubber capable of vulcanizing hard during vulcanization of the heel. obtained from sheets of vulcanized, hard sponge rubber of the required thickness as by punching the same therefrom.v

The heel preferably is formed with a tread designed to define an area or areas in which nails may be driven, spaced ribs 12, 12 of the same general shape as the outline of the heel being shown formed on the bottom thereof. the outer rib substantially coinciding with the outline of the insert.

The heel 10 is made by mounting a blank of soft rubber with the insert thereon infa mold adapted to exert pressure thereon during vulcanization suchthat the soft rubber will How about the edges of the insert as illustrated at 13 to anchor the insert in the heel. The soft rubber also further interlocks mechanicallywith'the insert by flowing into the broken cells in the edges thereof.

' ltn addition to the mechanicalconnection between the body of the heel and the insert, the two also become chemically united during the vulcanizing process as will be understood by skilled artisans.

The pressure employed during vulcanization is such as to prevent expansion of the gases within the cells of the sponge rubber The inserts 11 may be from distorting the heel. As a further advantage, the pressure of the gas will conipensate for the expansion of the rubber dur mg vulcanization, so that no rind or overflow will occur, thus eliminating the usual trimming operations.

After the heels have been vulcanized, they may be shipped to factories for use on new footwear, the construction thereof per1nit ting their effective application with automatic nailing machines, there being no specially located holes which the nails must lind. \Vhen shipped to cobblers or for retail trade, the heels preferably are shipped with the nails started as shown in Figure 5.

it is to be noted that no special treatment of the hard sponge or cellular rubber is required so that. it may be elfectively bonded to the soft rubber of the heel, that it is both mechanically and chemically united to the body of the heel and that in use it will not split or crack. The heel also permits of easy removal and replacement by persons who desire to change their rubber heels about because of uneven Wear.

Llodifieations of the invention may be resorted to without departing from the spirit thereof or the scope of the appended claims.

\Vhat' is claimed is:

1. A soft rubber heel having a nail-receiving insert secured therein during vul- -anization thereofisaid insert being of vul- 'anized hard sponge rubber.

2. A soft rubber heel having a nail-receiv inginsert secured therein, said insert being of vulcanized hard sponge rubber.

A soft rubber heel having a nail-receiving insertof cellular hard rubber secured therein.

EDWIN JOHN KROEGER.

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