US 3347232 A
Description (OCR text may contain errors)
Oct. 17, 1967 A. GINSBURG 3,347,232
HYPODERMIC NEEDLE WITH RETRACTABLE TIP Filed April 26, 1965 IN VENTOR.
Abraham Ginsburg BY WWW ATTORNEY-5 United States Patent 3,347,232 HYPODERMIC NEEDLE WITH RETRACTABLE TIP Abraham Ginsburg, 4031 Sheflield Ave., Philadelphia, Pa. 19136 Filed Apr. 26, 1965, Ser. No. 450,595 Claims. (Cl. 128-221) ABSTRACT OF THE DISCLOSURE This invention relates to a hypodermic needle whose primary object is to provide a retractable pointed insertion tip and releasable means to hold it rigidly in place on the shank for insertion into a blood vessel so that after insertion, when the patient moves and the tip strikes the vessel wall, it will retract on the shank to thereby eliminate pain and injury to the vessel wall.
Another object of the invention is to provide a hypodermic needle with retractable tip of the character above described in which the releasable means to hold the tip in a rigid position for insertion into a blood vessel is a blood soluble adhesive so that the tip is free to retract on contact with the vessel wall within a relatively short time after insertion into the vessel.
Another object is to provide a hypodermic needle of the character described combining aretractable insertion tip and a new and improved means to lock the same under the skin or subcutaneous tissue and thus restrain to'and fro movement of the needle, thereby permitting more freedom of movement of the patient without fear of pain and injury to the blood vessel or dislodgement of the needle. 1
Another object of the invention is to provide a hypodermic needle of the character described with a new and improved angulated retractable insertion point which militates against accumulation of blood in a pocket around the needle when the tip is in its retracted position.
Another object of the invention is to provide a hypodermic needle with a retractable tip and locking means which is economical to manufacture and relatively easy to insert into and remove from a blood vessel.
These and other objects of the invention will become more apparent as the following description proceeds in conjunction with the accompanying drawings, wherein:
FIG. 1 is an elevational view of the needle embodying the invention per se;
FIG. 2 is an enlarged vertical sectional view through the forward end of the needle and illustrating the insertion position of the needle;
FIG. 3 is an end elevational view of the needle looking from line 33 in FIG. 2;
FIG. 4 is an enlarged vertical sectional view of the insertion tip retracted upon the shank of the needle;
FIG. 5 is an enlarged side elevational view of the locking collar mounted on the shank with parts broken away and shown in vertical section to illustrate details;
FIG. 6 is a side elevational view of the needle shown inserted in a vein and locked in the skin with the insertion tip retracted upon the shank with parts broken away and shown in vertical section to illustrate details; and
3,347,232. Patented Oct. 17, 1967 FIG. 7 is an enlarged vertical sectional view of a modified form of insertion tip shown retracted upon the shank.
Specific reference is now made to the drawings wherein similar reference characters are used for corresponding elements throughout.
The hypodermic needle of the instant invention comprises a substantially cylindrical shank 10 with a uniform bore 12 therethrough which terminates at its forward end 14 in a non-pointed edge which lies in a plane substantially normal to the axis of the bore. A radially extending lip 16 is provided at the top of edge 14, the purpose of which will appear hereinafter. At the other or rear end of the shank there is secured or integral thereat an adapter 18 for attachment to a syringe or a tube connected to a suspended container having an injectable fluid therein, as is well known in the art.
At the forward end 14 of the shank, a substantially cylindrical hollow insertion tip 20 is mounted for sliding movement on said shank, the forward end of the tip being cut at an angle to its axis to form an angulated pointed edge. The rearmost portion of the pointed edge of said tip is a shoulder 24 which is adapted to abut the lip 16 and prevent further forward movement of the tip off the shank. In this position, as seen in FIG. 2, the pointed edge 22 extends beyond the non-pointed edge of the shank and is ready for insertion into a blood vessel.
A releasable means is provided to hold the tip rigidly during insertion into a blood vessel. The means is preferably a blood soluble adhesive 26 which is placed against the rear edge 28 of the tip itself and against the adjacent area of the shank. To assist in placing the adhesive in proper position, a well or indentation 30 is provided in the shank at a position adjacent the rear edge 26 of the tip when the latter is in its forwardmost position with the portion 24 of its pointed edge abutting the stop lip 16. The blood soluble adhesive is preferably an equal mixture by volume of dextrin, gelatin, and water which is kept viscous at -200 F. and inserted in the viscous state into the well 30. When it solidifies, it causes the tip 20 to adhere to the shank 10.
A locking means is provided to engage the skin and restrain to and fro movement of the needle when it is in position in the blood vessel, which locking means obviates the necessity of using tie-downs, such as tape, rubber tubing, etc. This locking means comprises a collar 32 on the shank adjacent the adapter 18 which cooperates with the adapter. The forward Wall 34 of the adapter is preferably substantially normal to the shank axis and has a diameter which exceeds the outer diameter of the shank. The collar is formed of a band of knife edge cross section (see FIG. 5) which is wrapped around the shank and clinched in place so that its outer surface 36 tapers away from the adapter and towards the insertion tip. At its widest diameter which approximates the outer diameter of the tip 20, the collar is inwardly beveled to form a countersunk shoulder 38 which is spaced from and faces the shoulder 34 of the adapter, the portion of the shank between the shoulders being indicated at 40.
In use, the needle with the tip releasably held in the position shown in FIG. 2 is inserted through the skin 42 and moved therebeneath through the subcutaneous tissue 43. The insertion tip 20 pierces wall 44 of the vein or other blood vessel and moves into the vessel. As the tip pierces the vessel, the skin 42 slides over the tapered surface 36 of the collar, the puncture in the skin gradually enlarging until it reaches and rides over the shoulder 38 where it contracts to the diameter of the shank 10 at section 40. The skin is thus locked in place between the shoulder 38 of the collar and the shoulder 34 of the adapter, thereby greatly minimizing to and fro movement longitudinally between the needle and the skin even if the limb or other part of the body is frequently moved. The outer surface 36 of the collar 32 is tapered towards the tip, and its diameter approximates that of the tip to ease the action of inserting and removing the needle.
After the insertion tip 20 is in the blood vessel for a short period, such as a few minutes, the adhesive 26 dis solves, thereby freeing the insertion tip 20 for axial or longitudinal movement along the shank 10. Thus, if the forward pointed edge 22 of the tip touches or abuts the vessel wall 44, it immediately retracts upon the shank. This removes the pain and damage normally caused by the needle scratching and piercing the vessel wall in the conventional construction which employed a fixed insertion tip. As shown in FIG. 6, the tip can move back on the shank far enough so that only the non-pointed edge 14 of the shank will be exposed, and if this touches the vessel wall, it will not cause scratching and attendant pain.
A modification of the insertion tip 20 is shown in FIG. 7. The modification is to thepoint of the needle at its pointed edge 22. As seen in FIG. 4, at the edge 22 of the tip 20, a pocket 46 is formed between the edge 22 and the outer surface ofshank when the tip is in its retracted position with the non-pointed edge 14 of the shank extending beyond the pointed edge 22 of the tip. Although this pocket is small, it presents thepossibility of undesirable accumulation of blood therein. In order to overcome this, the insertion point, as seen in FIG. 7, is formed by cutting the insertion tip at an angle with the axis thereof reversely to the angle of cut of the edge 22 to form a chamfer 48 peripherally around said edge 22. The result is that the chamfer 48 tapers towards the shank 10 and terminates in a peripheral edge 50 which is'flush against the shank, thus eliminating the accumulation pocket 46 of the form shown in FIG. 4.
In practice, it has been found that good results are attained using an l8-gauge needle whose bore has a diameter of .030 inch and whose shank has an outer diameter of .050 inch along its entire length. The insertion tip 20 is made from 17-gauge tubing, and the tapered collar 32 has a maximum outer diameter at its shoulder 38 of .070 inch, and the shoulder 38 is spaced inch from the shoulder 34 of adapter 18. -It is understood, however, that the invention is, of course, applicable to needles of other dimensions.
A skilled artisan may make minor variations without departing from the spirit of the invention and the scope of the appended claims.
1. A hypodermic needle comprising an elongated hollow shank having a non-pointed end, a hollow retractable insertion tip having a pointed end and mounted for axial movement on said shank and releasable means retaining said insertion tip in a forward position where said pointed end thereof extends beyond said non-pointed end of said shank for insertion into a blood vessel, said releasable means including a blood soluble adhesive so that after insertion in the vein and dissolution of said adhesive abutment of said tip with the blood vessel wall will cause said tip to retract to a point where only the non-pointed end ofsaid shank will be exposed.
2. The needle of claim'l and stop means at said nonpointed end of said shank to prevent said insertion tip from sliding olr saidshank in a forward direction.
3. The needle of claim 2 and a well in the surface of said shank adjacent to said tip when the latter is in its forwardniost position to receive said adhesive for engagement with said tip.
4. A hypodermic needle comprising an elongated hollow substantially cylindrical shank having anon-pointed forward end, a substantially cylindrical hollow retractable tip mounted for sliding movement on said shank,-and having a pointed end wall adapted for insertion into a blood vessel, stop means limiting outward movement of said tip to a predetermined position where said pointed end thereof extends beyond said non-pointed end of said shank, and blood soluble adhesive means releasably retaining said tip in said predetermined position.
5. The needle of claim 4 wherein said pointed end wall of said tip lies in a plane which is at an acute rearward angle to the axis of said tip and a chamfer peripherally around said end wall tapering forwardly of said tip to eliminate formation of a clogging pocket between said tip and said shank when said tip is retracted to a position wherein its pointed end is rearward of said non-pointed end of said shank.
References Cited UNITED STATES PATENTS 1,087,845 2/1914 Stevens 128-221 3,099,988 8/1963 Ginsberg an 128-221 3,204,634 9/1965 Koehn 128221 RICHARD A. GAUDET, Primary Examiner.
D. L. BAKER, Assistant Examiner.