US2891285A

US2891285A - Method of making a mold for casting a shoe last

Info

Publication number: US2891285A
Application number: US557390A
Authority: US
Inventors: Kaplan Harry
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-01-04
Filing date: 1956-01-04
Publication date: 1959-06-23
Anticipated expiration: 1976-06-23

Description

June 23, 1959 H. KAPLAN 2,891,285

METHOD OF MAKING A MOLD FOR CASTING A SHOE LAST Filed Jan. 4, 1956 v 3 Sheets-Sheet 1 g 32 32 28 f 2s 28 32 s2 26 Q I INVENTOR.

HARRY KA PL A N i BY A A FIGQ?) 74%) ATTORNEY 2,891,285 METHOD OF MAKING A MOLD FOR CASTING A SHOE LAST Filed Jan. 4, 1956 H. KAPLAN 5 Sheets-Sheet 2 June 23, 1959 IJVVEN'TOR.

HARRY 'KAPLAN Y ATTORNEY June 23, 1959 H. KAPLAN METHOD OF MAKING A MOLD FOR CASTING A SHOE LAST 5 Sheets-Sheet 5 Filed Jan. 4, 1956 INVENTOR. HARRY KAPLAN Y ATTORNEY United States Patent 2,8 9 1,285 Patented ,June 23, 1.9.5.9

fiice METHOD OFMAKING AMOLD'FOR CASTING A SHOE LAST Harry Kaplan, Philadelphia, Pa. Application January4, 1956, Serial No. 557,390 1 Claim. (Cl. 1855.tl5)

My inventionrelates to-a method of making a mold for casting a shoe last foruse in making shoes and more particularly for making shoes to be worn by persons having defective feet.

placedon one ofthe'foot supportsof the apparatus shown in Fig. l.

Fig. 4 is a vertical sectional View illustrating the first step in carrying out my invention, the foot itself being shown in elevation.

Fig. 5 is an exploded view tshowing the shell or mold formed according to the step shown in Fig. 4, after the same has been removed from the-foot.

Fig. 6, shows the two-part shell of Fig. 5 assembled and ready for pouring plaster of Paris or other setting material to. form a last.

Fig. 7 is a vertical sectional view of a last formed in the .Shfill of Fig. 6, 'theshell itself being renewed.

Fig. .8 shows the last of Fig. 7 cut .verticallyto .form separableinstep andheel portions to permit withdrawal of the last from the finished shoe without destruction of thelast.

Fig. 9 is a fragmentary and diagrammatic view showing a guage which is applied to the knees of the person to be fitted so as to insure that the last produced according to the invention will compensate for any difference in length of the legs of the person.

The apparatus shown in Figs. 1 and 2 includes a platform 10 suitably mounted on a frame or pedestal 12. for supporting the various parts of the apparatus. The apparatus itself includes a pair of

mats

13 and 14 which are formed of extremely resilient material such as foam rubber or its equivalent to the end that, when a human foot is pressed on the mat, the upper surface of the mat will yield and will follow the contour of the sole of the foot. In other words, if the impression made on mat 14 could be frozen before the foot is lifted, the upper surface of the mat will have a contour which is a counterpart of the contour of the bottom or sole of the foot. In Fig. 4 only two irregularities are shown at 16 and 18, but this is only by way of illustration as the number, size, location and shape of the irregularities would obviously vary from foot to foot. For the purpose of this application, it is only necessary to point out that the thickness and resiliency of the mat need only be such as to accommodate all conceivable deformations.

If a high heel shoe is to be made, two, or more, wedges 20 will be used to raise the rear portion of the mat, as shown in Fig. 2, to the desired extent. If a low heel shoe is to be made a smaller number of wedges are used used low-heel or fiatshoes.

2 and if a fiat, or heelless shoeisto be made, no Wedges are used.

In addition to providing for a heel of the desirediheight, the use of wedges also serves to orientzthelast-according to the slant oftheparticularfoot. For example thezfoot of a person who has always usedhighheelsacguires -.a configuration, or slant, which is different-from the configuration, or slant, of the foot of.-a;person rwhohasgalways Therefore, a .last amade zas described will produce a shoe having athedesired orientation. This insures comfort to the wearerbecausetthe shoe structure will corresponditothe.foot stmcture.

Platform 10 also supports uprights 22 :and 24 whichare best shown in Fig. 2 and which

carryhorizontallyextending rods

26 and 28. Rods 26 and .28 are-adjustable-on uprights 22 andf24 inthe direction:ofiarrowsllin Figs. 1 and 2 by anytconventional means30. @

Attheirjuxtaposed ends rods

22 and 24 carry ;;p1ates SZivvhichare adapted to be clampedagainst theilegs 34 of the person to be fitted to hold the same steady. Cooperating with clamps 32 is a combined clamp andlevel indicator which is shown in Fig. 9 and whichrconsists ofla yoke36and pendant rods 38 which are adapted to engage (the sides of the legs of the personsaboveztheknees. =R0ds 38 are laterally adjustable by :any suitable means 40 -.so-.as to clamp each pair of rods againstone legato prevent-tilting of the legs. Clamping the.legsqinthemannersshown in Figs. 2 and 9 prevents any movementdun'ngithe.casting of the last. Yoke 36 is also provided -with=a.-spirit on other level 42 which will indicate whetherwor not .the tops of the knees are at the same .level .andif one foot is higher than the other, .theshort foot-is:raised during the casting of the last to produce alast-having a.-hi gh'e.r heel. This compensates for .the difference .in i the lengths .ofthe legs.

The method ofcarrying-oubmyinvention .withthe apparatus above described is as follows.

The operator saturates strips 44 of .cloth or other flexible and absorbent material with a fairly viscous gpreparation of plaster of .Paris in .watertor-with-someiother fairly quickly setting composition and places the .strips on the surface of the .mats in such a fashion'sowas to completelycover the surface oflmats 13 and r14- The thickness of the strips, .or the thickness to which they are built up, should be such as to produce, whendry, the bottom of a shell or mold having the desired rigidity. The operator next places conventional toe box 46 at the places Where the persons toes will be during the formation of the mold. This is best shown in Fig. 4. Next, the feet are greased, with Vaseline or other substance which would prevent adhesion of the plaster of Paris to the skin, and are pressed down on

mats

13 and 14. With the legs clamped as shown in Figs. 1, 2 and 9, the operator proceeds to apply additional plaster of Paris, soaked strips 48 to the forward part of the foot to produce shell or mold portion 52 of Fig. 5.

The rear marginal portions 54 of shell portion 52 and the edge 55 of rear portion of the sole of the foot are now greased and shell portion 56 is produced in the man ner described. Greasing marginal portions 54 and the edge 55 of the sole prevents shell portion 56 from adhering to the forward portion of the shell portion and to the edge of the sole so that when the shell or mold hardens,

shell portions

52 and 56 are pulled off the foot intact as shown in Fig. 5. To form a mold in which the last can be cast,

shell portions

52 and 56 are brought together and plaster of Paris soaked strips 58 are applied to hold

mold portions

52 and 56 together to form in integrated shell shown in Fig. 6. The inside of the mold of Fig. 6 is now also greased to prevent adhesion, and it is ready to receive plaster of Paris or some other preparation to form the last of Fig. 7. Prior to the pouring of the last 3 during the pouring operation.

tudinal axis which is generally designated by broken line 60 in order to narrow the mold in its transverse direction enough to compensate for the expansion which takes place The longitudinal halves of the mold of Fig. 6 are held .together by transversely wrapped strips, not shown, similar'to strips 44. Before plaster of Paris is actually poured into the mold of Fig.

6, I place transverse wires 62 across upper edge 64 of the mold so as to support a plate 66 which carries

pendant tubes

68 and 70. All of the tubes have enlarged lower ends 72 to anchor the tubes in the finished last. Tubes 68 are internally threaded for engagement with bolts 74. Tube 70 is unthreaded and is adapted for engagement with the conventional lasting pin which supports the last, in upsidedown position during the actual making of the shoe. With plate 66

carrying tubes

68 and 70 supported on cross wires 62, plaster of Paris is poured until the mold of Fig. 6 is completely filled. If desired, I may use spaced longitudinal wires 76 to reinforce the last. Also, I provide blocks 78 of wood, or other nail-receiving material in holes 80 provided in the bottom of the mold of Fig. 6 so that,-when the mold is removed, blocks 78 will be embedded in the finished last. After the plaster of Paris has hardened, strips 58 are removed and mold sections-52 and 56 are removed to produce the finished last of Fig. 8.

In order to be able to remove the last from the shoe built thereon, I remove plate 66 and bolts 74 and I cut the'last transversely as at 82. A piece of leather or the like 84 is placed between the two portions of the last to compensate for the material which is lost during the transverse cutting of the last; The forward and rear portions of the last are again secured together by plate 66 and bolts 74 and the last is ready for the building of a shoe thereon in the usual manner. When it is desired to remove the last from the finished shoe, bolts 74 are disengaged from tubes 68 and plate 66 is removed. 7 Next, the piece of leather 84 is pulled out so as to give room for forward movement of the heel portion of the last to a position to permit its removal from the last; The forward portion of the shoe is now moved rear- 'wardly within the shoe and removed. The portions of the last are re-assembled together and the last is ready for re-use.

The apparatus and method described in this applica- While making the mold in two sections, as shown in Fig. 5, is satisfactory for most cases, it is within the scope of my invention to make the mold in more than two pieces. More specifically, if the foot has bunions or other defects which would make removal of section 52 or section 56 from the foot difiicult, either of these sections could be made in two parts by building one part, greasing its edges and building the overlapping part thereon in the manner described in connection with

sections

52 and 56.

What I claim is:

The method of making molds for casting shoe lasts, which method includes placing a pair of impressionable mats, one for each foot, on a rigid support, placing flexible elements which are impregnated with a quick setting composition on each of said mats, vertically aligning the legs of a person in a sitting position with reference to the respective elements, horizontally aligning the knees of said person, clamping said legs in said aligned positions, greasing the feet, adjusting said flexible elements to bring them into firm engagement with the soles of the feet respectively, covering the toe and instep portions of the feet with fiexible elements which are impregnated with a quick setting composition, allowing said composition to set whereby first shells are formed which engage the sole, toe and instep of the feet respectively, greasing the rear marginal portions of said shells, covering the heel and ankle portions of the feet with flexible elements impregnated with quick setting composition, allowing said composition to set to form second shells, the front edges of which overlap the rear edges of said first shells, removing said second and said first shells from the feet, respectively, and securing said second and said first shells together to form molds which correspond to the respective feet.

References Cited in the file of this patent UNITED STATES PATENTS