US2350053A - Bottom filler for shoes - Google Patents

Description

y 1944- H. G. LUMBARD 2,350,053

BOTTOM FILLER FOR SHOES Filed Dec. 7, 1943 Patented May 30, 1944 UNITED STATES PATENT OFFICE 2,350,053 BOTTOM FILLER FOR snons Henry G. Lumbard, Auburn, Maine Application December 7, 1943, Serial No. 513,227

2 Claims.

This invention relates to bottom fillers for the forepart cavity of shoes and consists in a novel shoe bottom structure possessing advantages which have been long sought by the industry.

For many years the shoemaking industry has contended against two incompatible requirements in the endeavor to produce a perfect shoe bottom. In the first place the forepart, which is repeatedly and severely flexed in every step taken by the wearer, must be highly flexible if the shoe is to be worn with comfort. In the second place the bottom must be thick enough and have enough strength and body to protect the foot of the wearer from the discomfort of feeling every under-foot roughness. I have discovered a satisfactory solution for this old and dimcult problem by making a new combination from shoemaking elements that have been heretofore available but never before combined as I now propose to combine them and never before used to accomplish the highly desirable results achieved by my invention.

Plastic fillers have been used for many years, and while these are satisfactory from a standpoint of flexibility, they tend to become deformed and displaced in th shoe bottom by a process of slow flow so that the insole does not remain flat under the foot of the wearer but develops objectionable hollows and cavities. On the other hand, a multitude of different fillers of solid sheet material have been used of every conceivable composition and in a great many different physical shapes, but all of these sheet fillers have tended to stiffen the shoe bottom by the well known plywood effect and this has been the case even though the material of the sheet filler has been flexible itself and even though perforated or transversely grooved.

I have discovered, however, that all the objections above discussed may be avoided by preparing sole filler blanks from a sheet of firm insole stock by transversely and discontinuously slitting the sheet and expanding it as a whole so as to cause separation of the opposed edges of each individual slit. Having prepared the sheet stock in this manner, the filler blanks are cut to size and secured to the outer face of the insole within the overlasted margin of the upper.

In preparing the filler of my invention we start with a firm solid piece of insole material. It is then slashed in the manner explained and in or subsequent to the slashing operation the material is expanded. The usual procedure is to over-expand the material and then permit it to relax to some extent but not to go back to its original position but in any case to leave the op- The filler is then inserted in the shoe in this expanded condition and will accordingly bend without resistance and in no way impair the flexibility of the insole with which it is associated.

The filler of my invention can be used in any type of shoe that carries a filler and can be designed to provide the same thickness of material as the thickness of the overlasted margin of the upper or of th rib in a welt shoe and so prevent the insole from caving in when worn. The filler holds the insole unto the level of the sides of the shoe when worn regardless of its type of manufacture. The material of the filler is selected for its depression-resisting qualities, that is to say, it should be of sufliciently firm textur to eliminate any possibility of flow under conditions of heat and pressure in wear or of matting down as might occur with a felted structure. One suitable material is available on the market under the trade name of Darex and comprises a porous paper stock impregnated with a rubber compound. Any other tough fibrous sheet material may be used in the construction of th flller of my invention. In my prior Patent No. 2,181,787 I have disclosed a flexible insole made from sheet stock which is suitable also to be utilized in preparing fillers in accordance with the present invention.

The features and characteristics of my 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 drawing in which,

Fig. 1 is a view in perspective showing a sheet of filler material with a single filler blank cut therefrom;

Fig. 2 is a view in perspective of a filler blank;

Fig. 3 is a fragmentary view in perspective and on an enlarged scale illustrating the process of slashing and expanding the sheet material;

Fig. 4 is a view in perspective showing the filler of my invention in position in the bottom of a welt shoe; and

Fig. 5 is a fragmentary view of the forepart of a cement lasted shoe embodying my invention.

In preparing the filler of my invention a sheet In of artificial leather, flbreboard, Darex or the like is selected of the thickness required in the filler. The sheet is then slashed by rows of closely adjacent short slashes ll extending entirely through the material and from side to side, the individual slashes intersecting the edges of the sheet wherever they happen to fall. The slashes II are accurately aligned in their respective rows posed edges of each individual slash spaced apart. and are staggered in adjacent rows. The material of the sheet I0 is expanded in such a manner as to space the opposed edges of each individu'al-slash or slit from each other to such, an

? extent that they do not make contact when the sheet or filler is flexed even to an extent greater than that at which it is flexed in ordinary wear. The step of expanding the material may be effected after the slashing operation or it may be effected simultaneously with the slashing operatlon as suggested in' Fig. 3. In this instance slashing is effected by a flat -blade if having a cutting edge beveled at an angle suillciently obtuse to stretch the stock substantially where it remains unsevered between the ends of adjacent slashes II. V a V Bole filler blanks I! may now be cut from the slashed and expanded sheet III by dies or by means of a pattern giving the flller the exact or" approximate size and outline of the cavity in the forepart of the shoe-wherein the flller is to be used. A filler blank I! as removed from the sheet I0 is shown in Fig. 2.

In Fig. 4 is shown a welt shoe having an insole I 4, an upper I! having its margin is over-lasted about the heel seat portion of the insole and secured to a welt l1, and an insole rib which extends throughout the shank and forepart of the shoe. In this instance the insole rib defines the forepart cavity which is to be occupied -by the filler l2. After the welt I! has been sewn and trimmed the filler blank if is fastened in place upon the outer face of the insole II and lies with its outer face substantiall flush with the surface of the welt I! thus completely filling the forepart cavity with solid material but without in any way impairing the flexibility of the insole with which it is associated. In Fig. 4 the upper is shown as lasted upon a last 20 and the shoe therein shown is completed by having an outsole I 8 sewn to the welt.

In Fig. 5 I have shown the application of the filler of my invention to a cement lasted shoe having an upper 2! with .its margin overlasted upon the outer face of an insole 24 made in accordance with the process of my Patent No. 2,181,-

787; that is to say, the insole 24 is made flexible by the same treatment that is used to provide the flexible flller II. In this instance the thickness of the filler is determined by the thickness of the over-lasted margin 28 of the upper 25 and may be somewhat less than the thickness of a filler required in a welt shoe.

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

1. In a flexibleshoe having an insole with an upper overlasted upon its margin and an outsole.

the combination with the insole, of a flexible filler comprising a blank of insole stock fitted within the over-lasted margin of the upper upon the outer face of the insole and transversely slashed in ad- 'jacent parallel rows of short, aligned, through and-through slashes extending from edge to edge of the filler and intersecting both edges thereof, the material of the filler being expanded and the opposed edges of each individual slash thereby separated sumciently to remain out of contact when the shoe bottom is flexed in wear.

2. ma flexible shoe the combination of an insole transversely slashed in discontinuous rows of individual slashes, in combination with a flller of firm insole material approximately filling the forepartcavity of the shoe bottom and lying upon the outer face of the slashed insole, said filler itself being transversely slashed in parallel rows of short through-and-through slashes extending from edge to edge and having its material expanded whereby the opposed edges of each individual slash are separated and remain out of contact when the shoe bottom is flexed in wear.

HENRY G. LUMBARD.

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