US2573547A - Amalgam carrier - Google Patents

Description

Oct. 30, 1951 w. s. cRowELL AMALGAM CARRIER Filed April l0, 1946 lmventor Ctttorneg 7' Patented Oct. 30, v1951 AMALGAM CARRIER Walter S. Crowell, Melrose Park, Pa., assignor to The S. S. White Dental Manufacturing Company, a corporation of Pennsylvania Application April 10, 1946, Serial No. 660,923

1 Claim. l

My invention relates to that class of dental implements that are generally known as amalgam carriers and are particularly adapted to insert amalgam or other filling material into a tooth cavity to form a stopping therefor, and is `especially directed to the means of connecting the plunger with the operating rod.

It has heretofore been proposed to construct amalgam carriers with the plunger and rod variously connected by a helically coiled wire or by a normally straight strand of Wire forced to bend in the curved barrel of said carrier, which construction has proven to be unsatisfactory for the purpose intended.

The principal objects of my invention are to provide an amalgam carrier having its barrel curved to direct its forward nozzle at a conveniently directed angle to the axis of its handle, and having its plunger and rod mounted to reciprocate in the bore of said barrel and connected by a section of flexible shafting whose outer diameter is substantially less than the diameter of the barrel bore.

Other -objects of my invention are to provide an amalgam carrier having its plunger and oper- `ating rod connected by a section of flexible shafting comprising a plurality of oppositely coiled helical layers of wires wound about a single strand of core wire.

Further objects of my invention are to provide an amalgam carrier with a removable and replaceable terminal tip through which the snugly fitted plunger is arranged to slide.

My invention also includes the novel arrangement of construction in which the finger-hold collar connects the separately formed barrel and tubular handle and in which the plunger retracting spring, which embraces the operating rod, is enclosed to exert -pressure tending to force the thumb trigger button rearwardly, and effecting the consequent withdrawal of the plunger in the nozzle.

Speciiically stated, the form of my invention as hereinafter more definitely described comprises an amalgam carrier having a tubular handle terminating forwardly in a collar serving as a finger-hold and which forms the mounting for the forwardly extending barrel which carries the plunger in its laterally deected terminal region. Said handle is provided with a ferrule serving as a buffer for the adjusting nut which is adjustable on the reciprocatory operating rod to vary the axial position of the plunger in the terminal nozzle and which is forced into engagement with said ferrule by the spring in the handle when the thumb trigger button is released to eiect withdrawal of said plunger.

My. invention also includes all of the various novel features of construction and arrangement as hereinafter more definitely specied.

In the accompanying drawings, Figure 1 is a side elevational View of an amalgam carrier conveniently embodying my invention; Fig. 2 is a central vertical longitudinal sectional View of the amalgam carrier shown in Fig. 1, on a greatly enlarged scale showing the relatively associated parts in their normal position; Fig. 3 is a central vertical longitudinal sectional view similar to Fig. 2 but showing the movable parts shifted to the forward limit of their movement; Fig. 4 is a transverse vertical sectional view taken on the line 4-4 in Fig. 2 on a much greater enlarged scale; Fig. 5 is a transverse vertical sectional view taken on the line 5-5 in Fig. 3 on the same scale as Fig. 4; and Fig. 6 is a fragmentary side elevational View of the flexible couplingkshaft and plunger.

In said figures, the tubular handle I terminates forwardly in the collar 2 which carries the forwardly extending barrel 3 having its forward portion 4 curvedly deflected downwardly and ter-'- minating in the removable and replaceable nozzle 5, which is removably engaged therewith by the screw threads 6.

Said handle I terminates rearwardly in a buffer ferrule 1 which is engaged therewith by the screw threads 8 and which has the peripheral knurling 9 by which it may be readily rotated, and the bore l0 through which the stem II of the thumb trigger button I2 slidably extends.

The forward region of the thumb trigger button stem II is conveniently provided with the screw threaded bore I3 into which the screw threaded rearward terminal region of the axially reciprocatory operating rod I4 is extended in threaded engagement therewith for axial adjustment.

Within the handle I and screw-threadedly embracing the rod I4 is the adjustable lock nut I5 between which and the collar 2 is disposed the plunger retracting spring I6 which is helically coiled about the rod I4' within the bore of said handle I, and which is arranged to be compressed by the forward movement of the thumb trigger button I2, as illustrated in Fig. 3, and which normally tends to force the adjusting nut I5 into engagement with the buffer ferrule 1, las illustrated in Fig. 2.

The forward end portion of the rod I4 is flexible and includes a length of flexible shafting I1 of relatively reduced diameter extended through the curved region 4 of the barrel 3, and formed integral with the non-ilexible portion of the rod I4 and the plunger I8 and flexibly connects themv together in a relatively definite axial relation.

The flexible shaft section Il of the operating rod I4 comprises an axial core wire I9 and the coiled layers 20, 2| and 22 of wire alternately laid in relatively ioppsi't'e directions, asbestishowniin Fig. 6.

My invention is advantageous in that it provides a positive action of the plunger I8 by reason of its connection with the operatingrod nI4 by the flexible shaft section I1 having the core wire I9 which maintains afdefniteaxi'al length between the rod I4 and plunger f3 faiidtheouter coils of said flexible shaft section provide faiplurality of rounded surfaces serving'las `restricted 5 Number parting from the essential features of my invention as defined in the appended claim.

Having thus described my invention, I claim: An implement of the class described, comprising a hollow handle having a forwardly extended barrel curvedly deflected laterally and terminating in a nozzle region, a plunger mounted for axial 'in'ovementfin saidfnozz'le region, trigger means t'inc'lud'ing'a stema-nd rod adjustably engaged in threaded relation and arranged to force dsaid plunger outwardly, a lock-nut arranged to retain-said stem and rod in axially adjusted relation, a section of flexible shafting including an 'axial"cere"wir-"e,fconriecting said rod and plunger, and'a spring I'contained in said handle and tending -to withdraw said plunger into said nozzle region. 1

WALTER S. CROWELI... y

REFERENCES CITED The yfollowing `references fare of record inthe 'file "of Cthis patent:

UNITED r'S'I'A'IS PTETS Name Date Arthur Sept. 11, 1906 `Goodhugh v Oct. 9, 19.06 .Holtz. r Sept. 25, 1923

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