US2893059A - Elastic last - Google Patents

Description

y 7, 1959 G. MEDIANO CAPDEVILA 2,893,059

ELASTIC LAST Filed June 23. 1955 INVEN TOR. GONZA LO MEDIANO CAPDEVILA United States Patent ELASTIC LAST Gonzalo Mediano Capdevila, Barcelona, Spain Application lune 23, 1955, Serial No. 517,571

6 Claims. (CI. 18-46) The ptes'ent invention relates to the construction of elastic lasts for use inmachines for vulcanizing rubber to a shoe upper or the like.

Machines of this type have used lasts provided with repellent or yieldable portions for the purpose of preventing cutting of the shoe upper under the high pressure that may be developed because of the action of the lateral compressor means. However, these constructions have the disadvantage of developing distortions on the elastic or yieldable portions which makes frequent replacements necessary causing the loss of time. Furthermore in these lasts the elastic portions are of a permanent type and therefore requires replacement in a workshop. It is an object of the invention to provide a construction without the above disadvantages.

A further object of the present invention is to provide a better bearing surface for the upper.

A still further object of the invention is to provide a construction wherein the elastic portions may be easily replaced by using the tools available without the necessity of sending the last to a special workshop.

A still further object of the invention is to provide a construction wherein the last comprises two parts which may be easily dismantled.

With the above and other objects in view which will become apparent from the detailed description below, a preferred embodiment of the invention is shown in the drawings in which:

Figure 1 is a cross-sectional view of the last taken upon Section Line 1-1 of Fig. 2.

Figure 2 is a bottom view with the solepiece removed.

Figure 3 is a perspective view of the elastic member for the front member, and

Figure 4 is a similar view of the elastic member for the rear or heel portion.

In the drawings the last comprises a front member or body and a rear member or heel portion 11 which are joined to one another by a sliding surface 12 extending essentially parallel to the curvature of the last upper portion so that the heel portion may be inserted or withdrawn from the shoe upper in a manner similar to the natural movement for placing a shoe on a foot. The heel member remains inserted within the upper during the movement of the front portion. A surface 13 limits the upward movement of the heel portion and it is provided with a guide slot 14 with which a tenon 15 upon the from member cooperates. In addition, both parts are secured in operative relation by means of a bolt 16 having a bayonet head 17 guided in a hole 18 provided in the upper portion of the front member in such a manner that it extends vertically to the heel portion. A hole 19 is provided in the heel portion with a cross-section corresponding to that of the head 17 and the latter is engaged with a corresponding bayonet housing 20.

The last, together with the heel portion is undercut along a surface extending parallel to the lower surface and as indicated in Figure l by the lines 21 and 22.

The lateral edges of the member 10 adjacent the sur- I 2,893,059 Patented July 7, 1959 face 21 have an instep construction and form the housing 23. The toe portion of the body member 10 is cut away at 24 which extends the entire height of the toe. The surface 21 is provided with transversely extending slots 25 of approximately rectangular cross-section which extend to the housing 23.

The body member 10 is coupled to an elastic member comprising two lateral members 26 as shown particularly in Figures 2 and 3 which extend into the housing 23 so that they complete the lateral surface thereof from the toe section to the surface 12. The members 26 are maintained in laterally spaced relation by two cross members 27 which fit into the slots 25 and at the front end thereof by a body 28 designed to fit against the surface 24 and complete the outer shape of the toe.

A recess having a threaded bore 29 and a larger unthreaded bore 30 is provided in the surface 21 and extends inwardly into the front member 10 between the grooves 25. A similar construction is provided at the toe end of the front member and the elements thereof have the same reference numerals.

The lower portion of the last is completed by means of a metallic plate 31 which fits on the surface 21. At locations facing the portion above described the plate 31 has two extensions 32 which are received in the portion 30. The extensions are hollow and at the bottom 33 are provided with a central opening for receiving the screws 35 with the heads 34. The screws 35 are threaded into the portion 29. The relative measurements of the above elements are such that the heads 34 are sunk within the extensions and are then covered by rubber plugs 36 which are secured by pressure within the extensions.

The last, when assembled, has an elastic peripheral portion capable of taking any undue or dangerous stress that may be applied by the lateral knives of the vulcanizing machine against the shoe upper. The extensions 25 may also be entirely provided in the plate 31 or partially in both members.

The heel portion 11 has an instep 37 which extends upwardly a substantial height as shown in Figure 1. This housing completely encircles the heel and abuts against the surface 12. In this housing there is fitted a piece 38 made of rubber or similar elastic or flexible material and this construction completes the rear and lateral surfaces of the heel. The member 38 is shown in Figure 4 and is provided with a cross member 39 near its front end to maintain the lateral relationship of the sides. The cross member 39 is received in a transversely extending groove 40 formed in the surface 22. The construction is similar to that described for the grooves 25.

The elastic member 38 being placed in position as shown in Figure 1 is then secured by the plate 39 which completes the lower surface of the heel. It is then held in position by means of a screw and extension combination similar to that described for the plate 31. The elements thereof have the same reference characters. The plate 39 is prevented from rotation by means of a tenon 41 received in a corresponding hole formed in the surface 22.

In this case also the housing for the member 38 may extend partially into the plate 39. Also the plate 39 may be formed so that its lower surface is left as a continuation of the lower surface of the plate 31.

When wear or other damage develops in the peripheral elastic members it is merely enough to withdraw the blocks 36 with a screw driver, release the screws 35 and withdraw the plates 31 or 39 thereby permitting replacement or repair of such elastic members.

With this construction there is no risk that the upper material will be cut by some overloaded spot inadvertently created owing to some dilferences in leather thickness or last distortion.

Various modifications with regard to size and shape as 'well as materials may be utilized without departing from the scope of the following claims.

lla m i. ,7 1, elastic last comprising a front member, aremov able rear rnrribr secured to said front member for facilitating fitting and withdrawing of the last into and out of shoeor the like, said front member having a peripheral recess adjacent the sole surface, a plate and a resilientmember completing the lateral and lower surface-of said frontrnember, means for removably securing said plate to said front member, said resilient member being located in said recess and said resilient member rec ivirig the shoe upper where the lateral compressor members of a vulcanizing press bear. I g P 2. An elastic lastas set forth in claim 1 wherein said resilient member comprises two longitudinal sections fitin said recess and means for holding said sections in laterally spaced relation located at the rear of said sections,

3, elastic last as set forth in claim 1 wherein said resilient member comprises two longitudinal sections fitting in said recess, transversely extending cross members fixed to said sections and said front member is provided with grooves within which Sara eras s iiiii'ibFsfiL' 4. An elastic last as set forth in claim 1 wherein said resilient member comprises two longitudinal sections fitting in said recess and said sections are joined at the front end thereof by a resilient body constituting the toe section of said last.

5. An elastic last as set forth in claim 1 wherein said removable rear memberextends throughout a substantial height of said front member and a second resilient member is secured to said removable rear member by means of a cross-member fixed theretoengaging in a transverse groove provided in said rearmember.

6. An elastic last as 'set forth irl claim 5 wherein said rear member is provided with a complementary member removably secured to said rear member.

en e W the e th s patent UNITED STATES PATENTS 10,679 Daugherty Mar. 2 1, 1854 224,234 Shorey Feb. 3, 1880 640,990 Brown Jan. 9, 1900 975,439 Lawrence Nov; 15, 1910

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