US617777A - Dentist s mercury-holder - Google Patents

Description

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ATENT DENTISTS MERCURY-HOLDER.l

SPECIFICATION forming part of Letters Patent N o. 617,777, dated January 17, 1899 Application led March 3 0, 1 8 9 8.

To a/ZZ whom, it may concern.;

Be it known that I, CARL SCHWEIZER, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented certain Improvements in Dentists Mercury-Holders, of which the following is a specification.

The object of my invention is to provide a mercury-holder for dentists which can be securely sealed to prevent the escape of the mercury and which can also be manufactured more cheaply than the ordinary holder, an object which I attain in the manner hereinafter set forth, reference being had to the accompanying drawings, in which-'- Figure l represents a sectional view, on an enlarged scale, of a mercury-holder constructed in accordance lwith 'my invention; and Fig. 2, side views of the various parts of the holder detached from each other.

An ordinary-mercury holder such as used by dentists consists of a hollow body, a nozz'le, and a cap, the cap screwing upon the threaded end of the nozzle until it is stopped by a shoulder thereon and said nozzle having .an expanded base which is screwed upon a threaded projection on the hollow body. There are two objections toa mercury-holder of this character, the first and main objection being the leakage of mercury due to the fact that the cap is seldom, if ever, so accurately made that it will close the end of the nozzle when it seats itself upon the shoulder of the same, and the second objection being the cost of manufacture due to the fact that most of the threaded portions terminate in shoulders, and hence cannot be cut as readily as through-threads. I overcome these obj ections by constructing the mercury-holder as shown in the drawings, on reference to whichl represents the hollow body of the holder, having at the top an internally-threaded opening for the reception of the externallythreaded tubular nozzle 2, which is threaded throughout its length, except at the reduced end 3, and receives an internally-threaded cap 4 and an .internally-threaded sleeve or collar 5. In fitting the parts together the cap is screwed upon the end of the nozzle 2 until it rmly closes the end of said nozzle, whereupon the sleeve or collar 5 is screwed upon Serial No. 675,762. (No'model.)

the nozzle until it rests against the inner end of the cap, and the projecting inner end of the nozzle is then screwed `into the body of prevents the unscrewing of said nozzle when the cap is removed, while assurance can always be had that the end of the nozzle will be firmly closed by the cap when the same is reapplied before the inner end of said cap comes into contact with the outer portion of the sleeve 5. Hence the objectionable leakage of the old form of mercury-holderis effectually prevented. The construction also provides for readjustment in order to maintain a tight coveron the nozzle if any of the parts should become worn.

The tubular nozzle 2 has a contracted outlet-opening at the outer end, which widens into the full bore of the tube, and the latter is flared o r funnel-shaped at the .inner end,

-so as to provide for the free flow of mercury into the bore, which contains such a volume ot' mercury that a ready discharge from the contracted outlet of the nozzle is insured.

My improved mercury-holder can be manufactured more cheaply than one of the ordinary construction, as the nozzles 2 can be made by cutting up into short lengths long pieces threaded in an ordinary screw-cutting machine, and the two threaded openings in the body of the holder and in the sleeve 5 can be rapidly formed, owing to the fact that these are through-threads-that is to say, the thread does not terminate at a shoulder.

The various parts of the device are intended to be made of well-seasoned boxwood or ebony, so that sharp threads can be cut in or upon them, and the joints between the va# rious parts are not likely to be loosened by shrinkage.

Having thus described my invention, I claim and desire to secure by Letters Patent- 1. A dentists mercury-holder comprising a hollow body; an externally-threaded nozzle screwed into a threaded opening in said body,

a cap screwed upon the end of the nozzle and closing the opening therein, and a sleeve screwed upon the nozzle between the cap and between said cap andthe body, substantially 1o body and having a bearing upon the latter, as speeied.

, substantially as specified. In testimony whereof I have signed my 2. Adentists nierenry-holde1,comprisinga name to this specification in the presence of hollow body, :Ln externally-threaded nozzle two subscribing Witnesses. screwed into a threaded opening in said body CARL SCI'IVEIZER. and having;i L bore contracted in diameter at lllitnesses: :tndnezu1 the outer end, zt cap screwed upon FRANK E. BECHTOLD, the end of the nozzle, and a sleeve interposed JOS. Il. KLEIN.

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