US2560162A - Needle structure - Google Patents

Description

vvides a continuation of the cannula bore.

Patented July 10, 1951 NEEDLE STRUCTURE Garwood W. Ferguson, Paterson, N. J., assigner to Becton Dickinson and Company, Rutherford, N. J., a corporation of New Jersey Application February 10, 1950, Serial No. 143,399

(Cl. 12S-221) 4 Claims.

This invention relates to afunctionally improved hollow needle or cannula structure.

It is an object of the invention to furnish a structure of this naturegwhich may pierce layers of material or skin and tissue without severing a plug from such materials.

Accordingly, in the case of a needle which is caused to puncture a diaphragm, stopper or other sealing portion of a pharmaceutical closure, material will not be cut from such closure.r Therefore, there will be no danger of the bore of the cannula becoming clogged, nor will there be any danger of a plug dropping into the receptacle to which the seal is applied. Where the invention is embodied in a hypodermic needle and the latter pierces skin and underlying tissues no embolus will be cut.

An additional object of the invention is that of furnishing a device of this type which may readily be manufactured by quantity production methods and with minimum expense; the needle structure being equally applicable to cannulae which are merely intended to pierce closures or cannulae which are primarily intended for hypodermic injection purposes.

With these and other objects in mind, reference is had to the attached sheet of drawings illustrating one practical embodiment of the invention and in which:

Fig. 1 is a face view of a needle and showing the same mounted by a hub or coupling member such as would ordinarily be employed in connection with a needle. to puncture diaphragms of rubber or other materials providing pharmaceutical closures; 1

Fig. 2 is a fragmentary enlarged face view of the pointed needle end;

Fig. 3 is ya side view thereof;

Fig. 4 is an end view of the needle point;

Fig. 5 is a sectional side view of a thin material layer pierced by a needle, also shown in section;

Fig. 6 is an end view of the parts as shown in Fig. 5.

Referring primarily to Fig. 1, the numeral 5 indicates a cannula or hollow needle which, as shown, may be mounted upon a hub including a forward portion 6 and a tubular rear portion This hub conveniently includes as part of its assembly a shield 8. The forward portion 6 of the hub is formed with a bore 9 which proneedle is pointed at its outer end as generally indicated at I0 to furnish a piercing end or part.

Referring in detail to the structure provided adjacent the point of the needle it will be seen The as in Figs. 2, 3 and 4 that this may include a generally obliquely extending surface. This surface or zone preferably embraces forward side beve'ls I I, to the rear of which the ground surface I2 extends. Within the zone of surface I2 the end of the bore I3 is defined. To the rear of this bore is the heel portion of the needle. The forward bevel surfaces II merge as at I4 and this line of merger is continued to furnish the piercing point at the extreme end of the needle.

In accordance with the present teachings, the heel portion of the needle point is depressed as indicated at l5. Such depression extends to the rear of the zone of the ground surface. Also, this depression interrupts the rearvzone of the ground surface.

To provide a unit of this character, a cannula is cut to lengths in the usual manner. Also, in

the usual manner the end of the cannula is ground to furnish the obliquely extending surface as well as the side bevels Il which interrupt or form continuations of the forward end of that surface. Thereafter, the heel portion of the needle is subjected to pressure exerted through a press mounting a suitable tool. In this manner the depression I5 is formed to dene this heel portion. Thereupon, the cannula and the point are complete. At any stage in the manufacture, a suitable hub portion may be associated with the cannula.

As a result'of the depression which is formed to provide the heel portion, no plug will be severed from a layer or layers pierced by a needle embodying the present teachings. Rather, if a thin layer I6 is punctured as shown in Figs. 5 and 6, the layer will have a ap portion I1 extending laterally from it and usually in direct sliding contact with the outer surface of the cannula 5. This ap portion will be attached through a substantial part of its circumference to layer I6. Therefore, there will be no danger of the flap beingsevered and detaching from the main layer during the piercing operation.

Where a relatively thick diaphragm or other closure layer is punctured by the needle, the point and adjacent edges of the latter will cut an arcuate slit as they initially pierce that layer. This slit may extend through substantially Continued projection of the needle will result in this slit being stretched or spread by' the wedging action of the needle surfaces. Accordingly, a plug of material will in no case be deposited within the interior of a laboratory ilaslcv or bottle with consequent objectionable appearance to the contents of that receptacle and possible contamination of such contents. Neither will a plugcome into being which will tend -to or actually ride into. the lumen of the cannula.. Where the structure is embraced inhypodermic needles, no embolus will be cut and therefore the patient will experience no danger in this connection.

Thus, among others, the several objects ot the invention as speciiically aiore noted are achieved. Obviously numerous changes in construction and rearrangement of the parts may be resorted to without departing. from the spirit of the invention as deiinedby the claims.

1. A needle structure including a cannula I formed with a piercing point at one end. bevel surfaces extending rearwardly from said point and presenting a line of merger, a further surface extending obliquely from said bevel surfaces rearwardly across the cannula, a. heel portion at the rear end of said oblique surface and a depression formed in the heel portion.

2. A needle structure including a cannula formed with a piercing point at one end, a surface extending obliquely `from said point rearwardly across the cannula, the outer end oi' the cannula bore terminating in suchsuriace. a heel portion contiguous with said surface and having its forward boundary defined by the rear edge cannula bore terminating in such surface, a heel portion contiguous with said surface and having 'itsforward boundary deiined by the rear edge portion of the cannula bore and said heel portion being depressed throughout its entire area in the direction of the needle axis and below the outer cannula surface.

4. A needle structure including `a. cannula formed with a piercing point at one end. a surface extending obliquely from said point rearwardly across the cannula, the outer end of the cannula bore terminating in such surface, a heel portion-contiguous with said surface andhaving GARWOOD W. FERGUSON.

REFERENCES CITED The following references are of record in the Ille of this patent:

UNITED STATES PATENTS Number Name Date 2,137,132 Cooley a- Nov. 15, 1938 2,409,979 Huber Oct. 22. 1946 FOREIGN PATENTS Number Country Date 466,002 Great Britain May 20, 1937 453,877 France Apr. 16, 1913 739,717

France Jan. 16, 1933

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