US 530187 A
Description (OCR text may contain errors)
P. B. LASKEY. SYRINGE.
No. 530,187. Patented Dec. 4, 1894.
IITED STATES PATEN Fries.
PHILIP B. LASKEY, OF MARBLEHEAD, MASSACHUSETTS.
SPECIFICATION forming part of LettersPatent No. 530,187, dated December 4, 1894.
Application filed September 15, 1894. Serial No. 5Z3| N model-l To aZZ whom it may concern:
Be it known that I, PHILIP BrLASKEY, a citizen of the United States, residing at'Marblehead, in the county of Essex andState of Massachusetts, have invented certain new and useful Improvements in Syringes, of which the following is a specification, reference being had therein to the accompanying drawings. 1 I
In the use of hypodermic syringes by dentists, for the purpose of insertinga local an assthetic into the gums of patients before performing an operation, considerable difficulty is experienced in forcing the liquid into the tissue composing the gums owing to the density thereof which resiststhe entrance of the liquid. In the use of syringes for the purpose stated it'is necessary that the piston should be packed very tight to prevent leakage of the liquid, and when the pistons are thus tightly packed ittakes considerable force to overcome the friction in operating them, leaving little power for the injecting force.
My invention has for its object to provide a hypodermic syringe for 'dentistsnse which will be free from the objections noted, and which is provided with a resistance handle with which is connected a lever for operating the piston of the syringe, the lever being so arranged as to secure as much power as may be required in forcing the piston, inthe injecting operation.
Another object of my invention is to provide the needle end of the syringe with a porous disk or plug to serve as a filter for the liquid, and thus prevent any foreign matter from entering the liquid passage in the needle, said liquid passage being extremely small, and thus being liable to be clogged or stopped up by very small particles of solid matter.
In the accompanying drawings Figure 1 is a side view of a syringe embodying one form of my invention, and Fig. 2 is a section of the same. Fig. 3 is a detail plan view to show the operating lever, the piston rod being in section. Fig. 4 is a sectional viewof a somewhat simpler form of my invention than that shown in Figs. 1 and 2.
A denotes the body of the syringe, the same being preferably provided at its needle end with a removable cap a, in which is inclosed a rubber packing ring 0. in which is inserted a small disk or plug 5 of felt or other similar porous material'toserve as a filter and thus prevent the entrance of any solid particles into the tube of the hypodermic needle 0 which is screwed onto the syringe in the usual manner. For filling the syringe the cap a may be removed, and the liquid may then be poured into the inverted syringe.
Connected with the upper end of the body of the syringe is a resistance handle d, shown in Figs. 1 and 2 as being soldered or other-- Wise permanently attached to a collar d fitting around the upper end of the body of the syringe and held in place by means of a sleeve e which is fitted to turn freely on the body A and is partly threaded to engage the inside threaded portion of the said collar, a small flange a on the body A holding the sleeve and collar in place when the two are screwed together.
F denotes a piston rod andfthe piston carried thereby. The piston rod F is preferably provided with a series of annular ratchet notches f. Connected to the rear portion d of the handle (1, by the link h, is a hand lever'i provided with apawl i for engagement with the notches f of the piston rod F,a spring 2' bearing upon the said pawl for the purpose of holding it in engagement with the notches f of the piston rod. The link his provided with a block it which is rigid or integral therewith and which serves as a bearing to steady the piston rod against the push of the pawl '5'. This. block h also prevents the said pawl from catching in the notches of the piston rod when the latter is lifted or drawn out from the body or barrel A, the lever 'i, by which said pawl is carried, assuming the position shown in dotted lines, Fig. 2, when the piston rod is being thus lifted or drawn out of the body or barrel A.
When it is desired to use the syringe the operator grasps the handle (1 and lever 2' with one hand, while steadying the syringe with the other, and owing to the leverage afforded by the lever 1; the piston may be forced inward with considerable power, particularly with the co-operating aid of the relatively fixed resistance handle 01 which is grasped with said lever 1'; and thus however tightly the piston may be packed no difficulty is experienced in forcing the anesthaetic fluid into the tissue of the gums; and as the syringe will be steadily held when in operation the danger heretofore existing of breaking the delicate needles used is largely or altogether avoided. Also owing to the fact that the collar d to which the handle d is attached,and with which thehand lever dis also connected, is swiveled to the body of the syringe, so as to turn freely with the sleeve e on said body, these parts may be turned in any direction that may be desired to get at any portion of the patients month which it may be news sary to reach. It is, however, not necessary, in carrying my invention into edect, that the piston rod should be provided with ratchet notches or that the operating lever 'i should be provided with a pawl for engagement therewith, as the hand lever may have a permaueutpivotal connection with the piston rod,as shown in Fig. 4, and the hand lever may be fixedly secured to the body of the syringe, instead of having a swiveled connection therewith as shown in Figs. 1 and 2, without departing from the essential features of my invention.
Having thus described my invention, I claim and desire to secure by Letters Paten 1. A hypodermic syringe provided at its upper end with a resistance handle and with an operating lever having means, betweenits fulcrum point and operating end, for connection with the piston rod of the syringe.
2. The combination with the body or barrel of a hypodermic syringe, of a resistance handle having a swiveled connection with said body, an operating lever provided between its fulcrum point and its operating end with a spring pressed pawl, and a piston-rod carrying a piston and provided with a series of annular ratchet notches to be engaged by said pawl t9 force the said piston forward in the syringe.
3. The combination with the syringe having the piston rod F provided with the pisstonf, of the handle (I, the lever 71, means for operatively connecting said lever with said piston rod, and one or more links 71. for connecting the fulcrum end of said lever with the portion (1 of said handle.
4. The combination with the syringe barrel or body A, of the piston-rod F provided with a series of ratchet 'notches, the resistance handle connected with said barrel or body, the link It having the bearing block or portion h resting against said piston rod, and the lever t jointed to said link and provided with a spring-pressed pawl to engage the notches of said piston-rod.
5. The combination with the syringe body or barrel A, of the piston rod F provided with annular ratchet notches and carrying the piston f, of the collar d swivled to one end of said body A, the handle d secured to said collar, the lever '11 provided with a springpressed pawl for engagement with the notches of said rod, and the link it connecting the fulcrum end of said lever with the end d of said handle.
6. The combination with the syringe body A provided at its needle end with a removable cap a carrying the hollow needle c, of a porous disk or filter within said cap and serving to prevent particles of solid matter from entering the said hollow needle.
7. The combination with the syringe body or barrel A, of the removable cap a, the needle c removably attached to said cap, the packing ring a inclosed in said cap, and the por ous disk or plug b inserted in said ring.
In testimony whereof I aifix my signature in presence of two witnesses.
PHILIP B. LASKEY.
FOSTER L. MARSHALL, WM. B. LASKEY.