US1335475A

US1335475A - Process and apparatus for forming casts

Info

Publication number: US1335475A
Application number: US330717A
Authority: US
Inventors: Axel G Bergman
Original assignee: Leygrand & Co Inc
Current assignee: Leygrand & Co Inc; Leygrand & Company Inc
Priority date: 1919-10-15
Filing date: 1919-10-15
Publication date: 1920-03-30
Anticipated expiration: 1937-03-30

Description

30, 1920. 2 SHEETS-SHEET l.

A. G. BERGMAN. PPocPss AND APPARATUS PoP mamme cAss. APPLICATION lFILED OCT. I5, i919.

Patented Mar,

INVENTOR WITNESS A. G. BERGMAN.

PROCESS AND APPARATUS FOR FORMING CASTS. APPLICATION FILED OCT. I5, I9I9.

1,335,47@ Y Patented Main 30, 1920..

2 SHEETS-SHEET 2.

' UNrrED 'saafrEs PATENT oEEroE.

AXEL e. BEEGMAN,

TRUSTEE,

To all whom t may concern:

Be it known that 1, AXEL G. BERGMAN, a subject of the` King of Sweden, residing in the borough of Manhattan, city, county, and State of New York, have invented certain new and useful Improvements in Processes and Apparatus for Forming Casts, of which the following is a specification. y,

This invention relates toa process and 'apparatus for forming plaster or other similar casts, and is more particularly directed to the formation of a mold or matrix to be l rast as a guide for fashioning the socket of Such efforts have, however, been the limb.

since the casts have only partly successful,

been taken of the stump by simply iminers- Y ingvit in a solution of plaster of Paris, or similar substance, and permitting the latter to set. This produces a correct matrix of the limb as it normally eXists, but fails to take into account the fact that when the leg is used the full weight of the user is borne by the artificial limb in walking, with the result that the stump is put under a pressure which changes its Aform very materially. i

Under such pressure the muscular or fatty portions of the limb yield, with the eect that the bony sections are pressed against the socket and continued use becomes painful or impossible.

Accordingto the present invention I^pro vide a process and apparatus for making molds or casts which will conform to the shape of the stump while the latter is under substantially thev same pressure as is experienced in use. The result is vthat the socket of the artificial limbwhen constructed to conform to the cast thus made perfectly fits the stump under conditions of actual service. so that pain or discomfort in the. use of the limb is avoided:

' The. invention may be practised in several ways, but I prefer for simplicity to adopt a 'I prefer to OF NEW YORK, N. Y., ASSIGNOR, TO LEYG-RAND Sc COMPANY, INC.,

0F NEW YORK, N. Y., .A CORPORATION OF NEW JERSEY.

PROCESS AND APPARATUS FOR FORMING CASTS.

Specification of Letters Patent. Patented B131. 30, 192,0. Application filed October 15., i919. Serial No. 330,717. i l

method which enables the person whose cast is to be-taken to himself introduce the necessary pressure. Thus according to 'the preferred form I provide a receptacle of suitable size and shape in which the plaster of Paris, or other molding material, is introduced in fluid form, and I confine the fluid substance against escapewhile the stump is introduced within it, the user placing his weight, or a considerable part thereof, onto the stump, soth'at it is lput under-a pressure substantially similar to the pressure which vit will afterward bear when the artificial limb is worn. The invention includes ce1'- tain other features of improvement which will hereinafter be more fully described.

Referring to the drawings which illustrate one form ofthe invention,

Figure 1 is a diametrcal section vof an y appropriate form of receptacle for use in practlsing the present lnvention.

Fig. 2 is a diagrammatical view of a limb equipped for the molding` operation.

Fig. 3 is a view during the molding operation, the receptacle being shown in diametrical section.

Fig. 4 is a plan view of the ing I prefer to employ.

Fig. 5 is a plan of a rubber disk which is useful in practising the invention.

Referring to the drawing, cate a suitable mold receptacle which for the present purpose isbest elongated to an extent to receive the longest stump which is designed to bev molded. It is preferably tapered inwardly from top to bottom, and is form of stockkbest provided with-a lining member B which may consist of a sheet of metal preferably with unattached edges, so that it maybe sprung apart upon removal from the receptacle A. It is best to provide a lower lining disk C. Within the metallic lining arrange a flexible lining, or bag, which is best made of water-proof material, such asrubber sheeting or suitably prepared paper. The object of this lining is to practically contain the plaster of 'Paris mixture, thereby avoiding thesoiling of the mold proper or adherence `of vplaster of Paris thereto. Thereccptacle A ispreferably pro-V vided with a bead or lip A', both for stiifening purposes and also to provide a ,shoulder around which the top of the flexible llnlng'D let A indii band G.

In Fig. 2 I have shown the stump and l limb properly prepared for the casting operation in advance of the immersion of the stump in the molding material. I prefer to incase'the stump preferably up to lthe knee in the form of stocking indicated by the letter F in Fi 2 and shown attached? in Fig/1. It wil be noted from Fig. 4 that the upper part of the stocking 1*" is enlarged to an extent which is out of proportion to the limb forl a purpose to be shortly described. lOver the stocking and arranged at about the knee is a rubber, or other 'suitable disk-like sheet, such as is indicated by tlie reference letter E, and which is shown de tached in Fig. 5. The disk E is provided Ythe dis E is then turned downwardly and with a central aperture of smaller dimen` sions than the knee so that it hugs the knee ver closely 'and with considerable tension.

hen the stump has been suitably prepared as shown at Fig. 2, the mixture of plaster of Paris, or other molding material, is then made, and inthe case of plaster of Paris I prefer to mix the material with water to the consistency of a heavy creamor. light batter.

AThe stump is then immersed in theliquid and the edges ofthe disk E are brought over the top of the receptacle A and fastened down fairly tightly -by the use of some tension member,- such .as the rubber strip H. Thatpart of the stockin which -is enlarged and `lies above stretched over 'the topof the disk and the bead of the receptacle, and is' also fastened down by a suitable tension member, such as the rubber strip I.

The person whose cast is to be taken then preferably stands (in case one limb is still intact) and places his weight, .or a considerable proportion thereof, on the limb which has been partly amputated. The mold is elevated if necessary by the vuse of a stool or other support vuntil it is approximately the right heightso that` when pressure is l put upon the stump ythe user will be substantially erect.' l

The result of the weight of the user being placed upon the stump is that the Y latter descends farther into the a position which" is roughly indicated in dotted lines at L in Fig. 3 to the position shown 1n full lines. This displaces a considerable quantity of the molding fluid which tends' to overflow the mold. This is resisted, h owever, by the rubber disk E so that the parts assume .substantially the position of Flg. 3.

pressure,

vprocess may be mold passing from Care should, of course, be taken initiallyv to see-that there is sufficient level of the molding fluid to reach the top of the mold, and even beyond, when the weight is placed upon the limb. When the proper pressure is reached it is maintained until the mol-ding `fluid hardens and sets.

for themselves in the matrix. As the tension of the fluid is uniform on .all parts a very precisev and comfortable fit. of the subsequently formed socket is assured.

The precise degree of weight which` is placed upon the stump during the molding operation will differ somewhat withv different individuals, vbut -the best results are usually found when all the weight is placed upon the stump which the user can conveniently and comfortably stand. 'This will usually be 'considerably over one half the weight of the 'user and sometimes nearly allv the weight. AIghave found in practice that it is advisable to apply vaseline, or other grease,`to the stump before placing it in the stocking and` also to dampen the stocki-ng well with water. If any leakage takes place in the plaster of Paris this -will soon stop on account of the'hardening of the latter. When theplaster of Paris attains some degree of hardness the pressure upon the stump can berelieved, but it should be kept in place until the plaster ofvl-arisv has fully hardened.

pleted, care should be taken i-n removing the stump. It is advisable tov gently reduce the bring the stump into the passive condition and to work the muscles slightly to help introduce slightly by the vfinger so as to assist in this operation, whereupon the stump-may be easily withdrawn. v

4 l air between the stump andv g 'the mold. -The muscles may be compressed It will be understood that the specific very considerably varied without departing from the invention so long as the mold is made under pressure, shown asfone adapted for the purpose is susceptible to wide variation.

It will be also understood, of course, that after the matrix is made, a plaster, or other cast, will be taken and thatlthe socket of the artificial leg will be fabricated as a facsimile of the matrix of the stump obtained by the cast.. This can .be done by molding papier mch and that the form of apparatus is merely and by the use of the replica' iso While the latter is under pressure.

fluid.

2. A process of forming a replica of a stump in the production of artificial limbs, comprising forming a matrix of the'stump while the latter is under a pressure approximating that which the stump is under in the use of the completed limb. 7

3. A process of forming a replica of a stump in the production of artificial limbs, comprising forming a matrix of the stmnp and during the matrix forming operation placing the stump under a pressure by vforcing the latter into theV matrix forming 4:. A process of forming a replica of a stump m thee-'production of artificial limbs,

comprising placing tlie'matrix forming fluid in a. mold receptacle, introducing the stump therein, pressing inwardly upon the stump and confining the fluid against escape.

5. A process of forming a replica of' a. stump in the production of artificial limbs, comprising placing the matrix forming fluid in a mold receptacle, introducing the stump therein, pressing inwardl)Y upon the stump and confining the fluid against escape by a flexible connection between the limb and the top of the receptacle.

6. An apparatus for making matrices of' a stump or the like,

of forming a replica of a comprising a receptable4 Jfor containing the molding material, an opening for the introduction of the stump and means for placing the molding material under pressure.

7. An apparatus for making matrices of a stump or the like, comprising a receptacle for containing the molding material, an

" opening for theintroduction of the stump Aand means for placing the molding material under pressure, said means comprising a flexible 'disk through which the stump passes.

8. An apparatus for making matrices of' a stump or the like, comprising a receptacle for containing the molding n'iaterial, and a :flexible disk having an aperture through it. 9,'An apparatus for making matrices of' a stump or the like, comprising a receptacle forcontaining the molding material, and

a flexible lining member Within the mold and a flexible disk for the top of the mold having an aperture through it.

10. An apparatus for making matrices of a stump or the like, comprising a receptacle for containing the molding material, a separable metallic lining Afor said receptacle and a flexible disk 'for the top of said receptacle.

` 11. An apparatus for making matrices of a stump or the like, comprising a receptacle 'for containing the molding material, a separable metallic lining for said receptacle. flexible lining within said metallic lining .and a flexible disk for fitting over the mold.

in Witness whereof have hereunto signed my name.

AXEL G. BERGMAN;