US2944549A - Injection instrument - Google Patents

Description

July 12, 1960 R. H. ALEXANDER 2,944,549

INJECTION INSTRUMENT Filed Oct. 25. 1955 INVENTOR ROBERT H AuzxArwlztz 2,944,549 timed-Ju 12.12559 n on. '25,- 1955, sets... 542,693 a n This invention relates to an injection instrument and more particularly to a self-injection type hypodermic needle and its associated fluid chamber and support.

Self-injection hypodermic syringes or capsules usually employ a needle and an injecting fluid such as insulin enclosed within a resilient plastic shell. Initial pressure on the exterior of the shell causes the needle to pierce the shell, and continued pressure forces the fluid through the needle. Generally, this needle is formed as a seamless drawn tubing. One end of the tubing is shaped-to provide the needle point, while the other endis crimped to a stamped washer type base member. Self-injection needles having this structure are expensive to fabricate, and since it is employed in a throw-away type instrument, the cost of the complete syringe is an important factor. I

It is, therefore, an object of the invention to provide an injection instrument which is economical to produce. 7

A further object is the provision of an improved selfinjection instrument and capsule.

A further object is to provide a self-injection instrument having a needle inlet port arranged to allow unrestricted fluid flow through the needle.

Another object is the provision of a method for producing an improved injection instrument.

A still further object is the provision of an injection instrument having a needle which can withstand a substautial lateral force. 7 I

.The aforementioned objects are achieved in one aspect of the invention by providing a metal blank formed with a base and a tab which terminates in a needle section.

For a better understanding of the invention, reference is made to the following description, taken in conjunction with the accompanying drawings in which:

Fig. l is a plan view of a metal blank layout of the instrument constituting one embodiment of the invention;

Fig. 2 is a perspective view of the instrument made from the metal blank shown in Fig. 1; and

Fig. 3 illustrates the instrument employed with a selfinjection hypodermic capsule.

Referring to the drawings, aninjection instrument 11, made from a blank of flat stock such as stainless steel, is shown in layoutform in Fig. l as having acircular base portion 13 and an elongated member ortab 15 with threeintegral sections 17, 19, and 21.Section 17 is formed with a crook so that it terminates along a portion of one side of thetriangular brace section 19. Extending fromsection 19 and axially aligned therewith is the elongatedneedle layout section 21.

Instrument 11 may be made with any conventional metal blanking and forming apparatus such as one employing a precision progressive die.Section 17 is first it. support is. elongated'iendsection 21.. The are? f an swim I a Hhsni Im t m s e anotherto provide a needle terminating in the instrument- Pai sTh J s Qllfl a t rm t h sw ins, operation serves tooutwardly convey; the injecting fluid sr sd h iws :theisl tun n .6; wh h s r c bov saltfils r d ba 13 a lfi or. ss t c' 1. 1. 92 5 41? r tr n r b fl mv d ss the blank w h i k material in selected sections or by forming the blank with e ss s 'e was it can b f l ed back and fourth several times to form these section's.. a

Fig. 3 shows a self-injection syringe 21""vviiih'hiti cup-shapedwell 29 and aclosure member 31. The syringe is made of a resilient plastic material such as polyethyelene which may be sealed along the lip ofcup 29 and the edge ofclosure 31 by any convenient means such as by heat and pressure. Enclosed within the capsule isaninjection fluid 33 andinstrument 11. Integral with the base ofcup 29 is aledge 35 which surroundsand engagesbase 13 ofinstrument 11. The instrument base is forced underledge 35 to effectively position and maintaininstrument 11 within the walls ofcup 29.

After the instrument has been mounted uponcup 29 as described above, the cup is filled with the desired injection fluid and is subsequently sealed withclosure member 31. It can be seen that the capsule structure made in this manner enables the parts to be sterilized and sealed andlater an injection to be made without any further handling of the injecting fluid or needle.

A self-injection capsule constructed in accordance with and issafer to use. Due to the manner in whichbrace 19 folded back uponbase 13 so that triangular brace section is attached tobase 13 bytab section 17, the needle is provided with a firm but yieldable mounting. Therefore, a twisting or turning of the capsule during the injection period will not snap off the needle. In addition, a lateral pressure on the needle after it has been extended throughclosure 31 as far as possible will cause less strain onthe needle since the closure member will absorb some of they force and provide a fulcrum point at the upper edge ofbrace 19 rather than nearbase 13. Also, sinceinlet port 26 is spaced abovebase 13 in the embodiment shown, mis-handling of the capsule will not prevent a free flow of fluid through the needle. Regardless of the location or amount of pressure oncup 29, the fluid has access to the unrestricted opening.

Although one embodiment of the invention has been shown and described, it will be understood by persons skilled in the art that variations and modifications may be made without departing from the scope of the invention as definedby the appended claims.

What is claimed is:

l. A method of forming an injection instrument comprising the steps of fabricating a strip of material to provide a base portion and an elongated portion having three sections, folding the first section back upon said base, bending the second section to form a brace, and turning the third section to form a hollow needle.

2. The method of forming an injection instrument comprising the steps of fabricating a strip of material to provide a base portion and an elongated portion having three sections, folding the first section back upon said base, bending the'second section to form a brace extending substantially normal to said base, and turning the third section to form a hollow needle.

3. The method of forming an injection instrument comprising the steps of fabricating a strip of material to provide a base portion and an elongated portion having three sections, folding the first section back upon said base, bending the second section to form a brace extending substantially normal to said base, and turning the section to form a liollov v iieedle i I said brace.

4. A method of formingan injection instrument comprising the steps of blanking a strip of metal to form a Base portion having an elongated-portion extendinfgntl eref from and subsequently formingfsaid'elongated portion to provide a tab foldedback-uponsaid baseportion with'a hollow needle extending transversely of said base portion,-

- -5. injection instrumentforrned from ame't'al' blank comprising a base portion,-a tab extending from an; edge of said base portion substantially parallel thereto'teimi nating in a brace positioned centrally of said" base por tion, and a hollow needle depending from said brace trans{ verse to the baseportion formed with an inlet port spaced from said base portion.

6. A self-injection capsule comprising a resilient enclosure, a fluid disposed within said enclosure, and an injection instrument mounted upon an internal wall of said enclosure, said injection instrument being formed from a metal blank and comprising a base portion, a tab extending from an edge of said base portion substantially parallel thereto terminatinginia brace positioned centrally of said base portion, anda hollow needle depending from said brace transverse'to' the'base portion formed with nsi eti-p tp c dfm s d;b e por o I I ReferencesCited'in'the file ofthis patent UN T T PATE S 2,769,443 Dunrnire Nov. 6, 1956

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