US2854975A - Hypodermic syringe - Google Patents

Description

Oct. 7, 1958 M: J. COHEN 2,354,975

HYPODERMIC SYRINGE Filed Aug. '7, 1952 n u-- v---" juif-5T[gimp-4` 25 INVENTOR M ILTON J. COHEN ATTORNEY United States Patent HYPODERMIC SYRINGE Milton J. Cohen, Washington, D. C., assgnor to Miljam Instrument Corporation, Washington, D. C., a corporation of Delaware Application August 7, 1952, Serial No. 303,129

4 Claims. (Cl. 128-218) My invention relates to a hypodermic syringe and it is an object of the same to provide a syringe of this type which shall be simple and inexpensive, the syringe having a chamber in which a medicament can be stored for an indefinite period without danger of contamination due to leakage of air or uid into the chamber, and without danger of loss by leakage or accidental discharge of the contents. The syringe thus serves as a storage chamber but is in such condition that it can be put into use as a syringe at a moments notice, by unskilled persons as well as by personnel trained in the use of such devices. The cost is so low that the syringe can be discarded after a single use, i. e., it is in the class of so-called disposable devices for medical use.

Another object is to provide a device of the character described such as will store medicaments without chance of contact with any surface that might have a deleterious effect on the contents.

Another object is to provide improved means for ejecting the contents of the chamber through a hollow needle in a well-known manner.

Referring now to the annexed drawings, which are made a part of this application and in which similar reference characters indicate similar parts:

Fig. 1 is an elevation of the syringe of my invention, partly in section;

Fig. 2, a similar view With the parts in a different position;

Fig. 3, a similar view of -a modified form and.

Fig. 4, a detail of a part shown in Fig. 1.

In the drawings, reference character indicates a syringe barrel, preferably made of glass, and which may be a cartridge such as in common use as a container for dental liquid anesthetics, being closed at both ends by plugs of rubber or the like.

This barrel has been altered in form by forming an annular groove 11 therein to form a sort of neck near one end. A hub 12 is located in the barrel forwardly of the neck, the hub being made of rubber or of a suitable plastic, in -which a needle 13 is embedded and secured against movement. The hub has a shoulder at 14 that bears against the forward end of the barrel and a washer 15 of rubber or other material resistant to chemical action is located between a shoulder 16 at the forward end -of the neck 11 and the adjacent end of the hub, this washer preventing any contact of the contents of the chamber in the barrel with other parts at the forward end of the syringe, the needle 13 extending through the washer and tting tight therein. The forward end of the hub is reduced to provide a shoulder 17. A connector 18 is limited as to its movement in one direction lengthwise of the syringe by the shoulder 17, this connector being preferably made of metal such as can easily be bent at its rear end into the groove 11 at the neck portion of the barrel, the connector originally being cylindrical at its righthand end, as indicated in dotted lines in Fig. 1. Thus, the connector is held in the posi- ICC tion shown, whereby all the parts mentioned above are held in place. A cap 19 is mounted on the reduced end of the hub 12. This cap may be attached to the reduced end of hub 12 in any suitable manner, as by fitting closely about said end. It is so dimensioned that the end of the needle will project into the material of the cap, at least that part at 20 being made of rubber or plastic that is so soft and resilient that the needle can ex it and extend into it far enough to seal the cannula of the needle, but the remainder of the cap being relatively hard, inelastic or inflexible, thus constituting a dual-hardness cap, all more fully described in my copending applications Ser. Nos. 247,522, September 20, 1951 (now abandoned); 255,983, November 13, 1951 (now Patent No. 2,708,438); and 300,193, July 22, 1952 (now Patent No. 2,679,246), but which part 20 can spring back to place upon release of pressure by the needle. As more fully explained in my application Ser. No. 255,983, tiled November 13, 1951, the sealing of the needle prevents endwise movement of the plunger with relation to the barrel in either direction, and there is no danger of loss or contamination of the contents of the chamber when the cap 19 is in place as shown.

At the rear end of ther barrel, or at the end remote from the needle, there is a plug 21 that contines the contents of the same, and a plunger 22 is adapted to be inserted into the barrel to push the plug 21 and so force the contents of the syringe through the needle. A finger grip comprises an annular ange 23 projecting from a body 24 having a rearwardly extending part 25. The finger grip has a bore that is interiorly tapered from its forward end to its rear end, the forward end tting over the barrel and the rear end adapted to receive and guide the plunger 22. The shape 4of the bore of the linger grip helps to guide the plunger into the open end of barrel 10, the plunger pushing in the plug 21, which normally is ush with the end of the barrel. Now, when the user pushes against the end of the plunger with his thumb, while his lingers straddle the grip and the barrel, the fingers tend to clamp the grip onto the barrel and to reinforce the hold of the grip on the barrel by reason of the inner taper of the grip, instead of merely tending to slide the grip otf the barrel as usual, and produce a more effective discharge of the contained material of the syringe.

ln the modified form of Fig. 3 all parts may be as in the other form, except that hub 12 iills the space between the barrel and the connector, the washer being omitted, and the entire hub being made of rubber or other material that is resistant to chemical action.

It will be obvious to those skilled in the art that many changes can be made in the devices herein disclosed, all without departing from the spirit of the invention; and therefore l do not limit myself to what is shown in the drawings and described in the specification, but only as indicated in the appended claims.

Having thus fully described my invention, what I claim is:

1. A hypodermic syringe comprising a barrel having a circumferential groove deiining a neck portion, a plunger at one side of said neck portion, a hub at the opposite side of said neck portion, a needle permanently embedded in said hub, and a connector having retaining means at one end engaging the outer end of the hub and retaining means engaging in said groove, said retaining means holding the hub in place.

2. A device as in claim 1, wherein the second-named retaining means comprises a crimped end of the connector.

3. A device as in claim 1, including a rubber washer between the hub and the adjacent end of the barrel.

References Cited in the le of this patent FOREIGNI PATENTS France Dec. 1, 1902

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