US2937461A - Detachable top lift - Google Patents

Description

May 24, 1960 J. F. TRELA 2,937,461

DETACHABLE TOP LIFT Filed July 1s, 1957 United Seres, Parent LO f DETACHABLE TOP ALIFT Joseph F. Trela, 332 Jackson St., Lawrence, Mass. Filed July 16, 1957, Ser. No. 672,222

1 Claim. (Cl. 36-36)v This invention relates to detachable top lifts of the type having 'a single central post slideably fitting a corresponding axial bore in a heel. y

With the adventof transparent plastic ladies heels of extremely pointed outline, the problem of afxing top lifts thereto has become acute. It is still the general practice in the shoe industry to use three or four nails to aiix a lift of greater area than the heel and to then shave the periphery of the lift down to the size of the heel. The nails tend to spoil the appearance of a transparent heel and tend to crack a plastic heel. The shaving operation may also mar the heel and if the lift is dislodged it is time consuming to renail the same. Various central and multiple post type detachable lifts have been proposed in the art but with unusually small top lifts multiple posts weaken the heel and central posts cannot be cumbersome or involve numerous minute parts.

Many proposed detachable top lifts include a sleeve, or lining, which is iitted in the axial bore of the heelin order that the post may be secured thereto but such sleeves also weaken the heel by requiring a larger bore and of course the sleeve must be seated in the bore as an additional operation.

It is the principal object of this invention to provide a one piece, detachable top lift especially usable with sharp pointed heels wherein a single, integral slotted central post retains the lift in an unlined, axial bore of the heel from undesired axial or rotational movement.

Another object of the invention is to provide a detachable top lift which can be molded in one piece, from elastomeric material such as rubber, and yet will have the characteristics of more complicated structures of the prior art.

A further object of the invention is to provide a detachable unitary, top lift of moldable material having a single integral, central post embedded therein capable of gripping the unlined, bore of a heel frictionally, resiliently and abrasively.

Still another object of the invention is to provide such a detachable top lift wherein worn top. lifts expose a screw driver slot whereby the post may be turned to remove the same with a rotating movement.

Other objects and advantages of this invention will be apparent from the description of the drawing, the lclaims and from the drawings in which.

Fig. l is a side view in section of the preferred embodiment of the invention.

Fig. 2 is an enlarged perspective view of the detachable top lift shown in Pig. 1.

Figs. 3, 4 and 5 are perspective views, still further enlarged of modilied forms of posts.

Fig. 6 is a side view in section of a one piece detachable top lift in accordance with the invention.

Fig. 7 is a front view in section and Fig. 8 is a side view in section of a modification.

As shown in Figs. 1 and 2, 20 represents the heel of a ladys shoe which may be of wood or plastic in the upper portion 21 and of metal such as aluminum in the i 2,937,461 4llaterrted kMay 24, `1.960

lower portion 22. The portion V22 of currently popular heels may be only about threeeighths of an Ainch in cross section, creatinga heel underface 23 of small area. When the heel is entirely of transparent plastic material it will be apparent that interior attaching mechanism for a topv lift will be disclosed and must not be unattractive. When the lower portion 22 is of plastic, the driving of nails thereinto or the drive fitting of -a sleeve into an axial bore in the heel may tend to fracture the material of the heel. l Y t In this invention, regardless of the materialV ofthe portion 22 of heel 20, only a single, unlinedaxial bore such as 24 is provided which may be conveniently achieved by-a drilling operation. The bore 24 extendsl at least one half inch into the heel and its inner face 25 is smooth and of uniform Acircular cross section.v v f Y l The unitary, detachable topV lift 26 Vof ,the` invention includes the lift portion 27, usually ofgplastic, rubber or similar material, Yand the integral, upstanding central post 28. Post 28 is of uniformv circular cross Vsection and includes an axial slot 29 of uniform cross section forming two identical bifurcated portions 31 and 32, each of parti circular cross section. Post 28 is 'of resilient material such as metal or rubber whereby the portions 31 and 32 may be exed toward each other upon slideably entering bore 25 and will then tend to spring outwardly to resiliently engage the inner face 25 of the bore. The slot 29 extends from t-he free, terminal, tapered tip'33 of post 28 down to the plane of the upper face 34 of the lift 27. A plurality of spaced, sharp protuberances such as 35 and 36 are provided on the outer face 37 of post 28 preferably in the form of minute teeth, barbs, serrations or similar elements of an abrasive nature. The diameter of post 28 and bore 24 is substantally identical whereby the post must be forced into the bore with the portions 31 and 32 yielding toward each other until the post is entirely seated in the bore. Accidental axial withdrawal, or rotation of the lift around the heel axis is prevented by the combined frictional, resilient and abrasive engagement of the protuberances 35 and 36 with the smooth inner face 125 of the bore. When it is desired to replace a worn detachable top lift, the application of a pull by mechanical means on the exposed portion of post 28 will dislodge the same, permitting the substitution of a new unit.

Preferably the post 28 is of metal such as aluminum and is provided with a disc-like head 38 which is embedded in the material of lift 27 intermediate of the height thereof. The lift 27 may be of any suitable moldable material, such as rubber, plastic, metal or nylon and it is molded to exactly tit the the heel 20 in order to eliminate the above mentioned shaving and fitting step during manufacture.

A modication is shown in Fig. 3 in which the post 40 is slotted at 41, bifurcated at 42 and 43 and headed at 44 in a manner similar to post 28. However, longitudinally extending relatively sharp flutes 45 and 46 are provided on the outer face 47 for engaging the inner face 25 of the bore 24. The head 44 is apertured as at 48 to form webs of the moldable material of the lift and a plurality of integral prongs such as 49 are bent upwardly from the head to prevent turning thereof relative to the lift.

Another modification is shown in Fig. 4 wherein a post 51 similar to post 28 is provided with sharp pointed protuberances in the form of the helical drive screw threads 52and 53. The head 54 includes a screw driver slot 55 which becomes exposed when the lift wears down to permit rotational removal. The post 51 is applied to the bore 24 by hammering in the usual manner of a drive screw, the hammer blows being applied to the lift in which the head is embedded.

In Fig. 5, a post 60 is shown similar to posts 28, 40 and 51 except that machine screw threads 61 and 62 form the sharp protuberances on the outer face 63. The head 64 is slotted at 65 and 66 for receiving a turning instrument such as a screw driver.

In Fig. 6 a unitary, detachable top lift 70 is constructed in accordance with the invention by molding both the lift 71 and the -post 72 from the same resilient material such as metal, rubber, plastic or nylon. A layer of adhesive 73 is provided on the upper face 74 of lift 71 to affix the same to the heel and prevent rotation thereof. The protuberances 75 on the outer face 76 of post 72 rake rearwardly to permit advance and resist withdrawal of the post in a bore 25. t

In Figs. 7 and 8 a device similar' to that shown in Fig. 2 is illustrated wherein Athehead V80 of postI 81 is embedded in the lift 82. Lift 82' is of moldable material and provided with an integral upstanding rim of the moldable material as at .83, 84 and 85. The vrims 83, 84 and 85 extend on at least three sides of, or in at least three quadrants around, the lift 82 in order to form a three walled pocket or recess 86 for receiving the heel 87. Preferably the rims 83, 84 and 85 are beveled on their outer faces 88 and vertical on their inner faces 89 to present a novel and attractive appearance.

I claim:

A detachable top lift comprising a one piece body of elastomeric material in the shape of a lift, said body having a single integral, bifurcated, post upstanding centrally therefrom and the outer face of said post having a plurality of sharp protuberances integrally formed thereon for atxing said top lift in a heel bore.

References Cited in the le of this patent UNITED STATES PATENTS 2,428,259 Anstett Sept. 30, 1947 FOREIGN PATENTS 19,561 Great Britain Ian. 9,` 1892 of 1891 170,868 Great Britain Oct. y24, 1921 339,460 Great Britain Dec. 1l, 1930 341,244 Great Britain Jan. 15, 1931 845,769 Germany Aug. 4, 1952

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