A hypodermic syringe which has provisions for preventing more than one use thereof and rendering the needle inoperative and harmless. A device is mounted on the syringe which, after administering an injection, is manipulated to bend the needle portion of the syringe and concurrently retract the needle from its normally projecting position whereby the needle cannot accidentally cause injury to anyone.

This invention relates to an improved hypodermic syringe of the type which 
is disposable after a single use. The syringe of this invention cannot be 
used after the initial use thereof, and, after such initial use, the 
needle is bent and retracted so that it cannot cause accidental injury to 
anyone. 
The vast majority of syringes presently in use are designed to be used only 
once and then discarded. This type of syringe is typically constructed 
from injection molded plastic fitted with a needle or cannula, and then 
sterilized and packaged so as to maintain its sterility. When used, the 
package is opened, the syringe removed and filled with the drug or 
medication to be administered, and then discarded after such usage. 
Such syringes are generally provided with a removable cap which covers the 
needle before use so as to prevent accidental injury. The cap is removed 
before the medication is drawn into the syringe. If not misplaced or 
dicarded, the cap may be re-positioned on the syringe after use and before 
the syringe is discarded. The cap may, however, be easily removed again 
from the discarded syringe, thereby permitting illicit reuse of the 
syringe. Of course, if the cap is misplaced or discarded prior to 
administering the injection, the syringe must be discarded with an exposed 
needle. 
The problem of potential injury and illicit reuse of disposable syringes 
has been recognized and has been dealt with in a number of different ways 
by the prior art. One practice in hospitals is to utilize a special tool 
with which the needle is clipped off of the syringe and then discarded. 
Thus, the syringe is rendered inoperative and harmless. This technique, 
however, requires the use of an accessory tool which must be carried about 
by the hospital staff. Also, the discarded needles can present an injury 
problem. To counter this problem, it has been proposed that the severed 
needles should be ground up to render them harmless. This, however, 
presents a potential health problem since the needles can be infected with 
hepatitis germs, or the like. 
Another procedure for rendering the needle of a syringe inoperative and 
harmless is disclosed in U.S. Pat. No. 3,893,608, issued July 8, 1975 to 
E. A. Koenig. The Koenig construction includes a rod member formed as a 
part of the syringe, the rod member being detachable from the rest of the 
syringe after an injection is administered, and the rod including an 
offset chamber into which the needle is inserted. The offset in the 
chamber bends the needle and the rod member is frictionally telescoped 
onto the syringe over the needle so as to cover the needle. Thus, the 
needle is covered over and bent. 
I have devised an improved syringe having provisions for bending and 
retracting a needle after an injection has been administered. The syringe, 
in its preferred embodiment, is formed with a rotatable member attached to 
its needle-bearing end. The member has a passage through it through which 
the needle extends. The member is rotatable about an axis which is offset 
from the needle passage. Rotation of the member is about a post formed on 
the remainder of the syringe. As the member is rotated about the post, the 
edge of the member passage engages the needle and pulls the free end of 
the needle back beneath the member and the needle is wrapped around the 
post. Preferably, one complete 360.degree. revolution of the member 
passage causes the needle to be completely retracted between the member 
and the remainder of the syringe and, at the same time, be wrapped around 
the post. Thus, the needle is retracted and at the same time functionally 
destroyed. The syringe is thus rendered inoperable and incapable or 
accidentally causing injury. 
It is, therefore, an object of this invention to provide a hypodermic 
syringe which can be disabled and rendered harmless after a single usage. 
It is a further object of this invention to provide a syringe of the 
character described wherein the needle is retracted from its normal 
projecting position so as to render the needle incapable of accidentally 
harming anyone after the syringe has been used and discarded. 
It is yet another object of this invention to provide a syringe of the 
character described wherein the needle is bent during retraction so as to 
prevent the syringe from being used more than once.

Referring now to the drawings, FIG. 1 discloses a modified form of a 
generally conventional syringe, denoted generally by the numeral 2, which 
syringe 2 includes a preferred embodiment of the needle retracting and 
bending device formed in accordance with this invention. The syringe 2 
includes a hollow tubular portion 4 into and from which the medication is 
drawn and administered. Lateral finger grips 6 are disposed on either side 
of the tubular portion 4 to facilitate manual operation of the syringe. A 
piston member 8 is slidably mounted in the tubular portion 4 for filling 
and dispensing the medication in a conventional manner. A disk 10 is 
rotatably mounted on the end of the tubular body 4 remote from the piston 
8, and a hypodermic needle 12 is secured to the end of the tubular portion 
4, projecting therefrom through a passage 14 (see FIG. 3) in the disk 10. 
The protective sheath 16 is releasably pressed onto the disk 10 to protect 
the needle 12 during storage prior to use of the syringe 2. 
Referring now to FIGS. 2 and 3, the specific structure of the 
needle-bearing end of the syringe 2 is shown. It will be noted that the 
needle 12 extends through a passage 14 in the end wall of the tubular 
portion 4 so as to communicate with the medication chamber 5 which is 
within the tubular portion 4. Formed on the needle-bearing end wall of the 
tubular portion 4, and projecting therefrom, is a lug 18. It will be seen 
from FIGS. 2 and 3 that the passage 14 through the disk 10 communicates 
with a larger passage 20 through which the lug 18 extends. A 
circumferential rib 22 formed on the lug 18 engages the edge of the 
passage 20 so as to retain the disk 10 on the end of the tubular portion 
4. From FIG. 2, it will be apparent that the sides of the passage 14 are 
closely proximate to the needle 12. It will be noted that the axis of the 
lug 18 is laterally offset from the axis of the needle 12, and that the 
axis of the lug 18 provides an axis about which the disk 10 may be 
rotated, as shown in FIG. 4. 
Referring now to FIGS. 4 and 5, the mode of operation of the device for 
rendering the needle 12 incapable of hurting anyone or being reused is 
disclosed. Once the injection has been administered by depressing the 
piston 8, the disk 10 is rotated about the lug 18 through one or more 
360.degree. revolutions. This rotation of the disk 10 causes the passage 
14 to swing about the lug 18 whereby the side wall of the passage 14 is 
moved against the needle 12. Since the end of the needle 12 is secured to 
the end of the tubular portion 4 of the syringe 2, movement of the passage 
sidewall against the needle 12 causes the needle 12 to be drawn back into 
the passage 14 and wrapped about the lug 18, as shown in FIG. 4. Continued 
rotation of the disk 10 about the lug 18 ultimately results in complete 
withdrawal of the needle 12 with the latter being completely wrapped about 
the lug 18 and overlain by the disk 10. Thus, the simple manual operation 
of the disk 10 after administering the injection simultaneously renders 
the syringe harmless and non-reusable. 
Referring now to FIG. 6, an alternative embodiment of a syringe formed in 
accordance with this invention is disclosed. The syringe of FIG. 6 
includes a tubular portion 4 having a medicament chamber 5 and a needle 
12. A rotatable disk 10 is mounted on the needle-bearing end of the 
syringe and a protective cap 16 is releasably mounted on the disk 10 to 
cover the needle 12 prior to use. A forwardly projecting annular flange 24 
is formed on the tubular portion 4, as is a central, forwardly projecting 
lug 26. An annular recess 28 is formed on the disk 10 for reception of the 
flange 24, and a blind hole 30 is formed in the disk 10 for reception of 
the lug 26. The blind hole 30 has an enlarged counter bore 32 which is 
radially spaced from the side wall of the lug 26 to form a covered chamber 
into which a portion of the deformed needle will be drawn. A passage 14 
extends through the disk 10, the needle 12 projecting through the passage 
14. It will be noted that the annular flange 24 and the lug 26 are coaxial 
while the passage 14 is off center from the common axis of the flange 24 
and lug 26. Thus, when the disk 10 is rotated, the sides of the passage 14 
move against the needle 12 and, since the inner end of the needle 12 is 
fixed, bend the needle 12 around the lug 26 and pull the needle 12 back 
into the counter bore 32. The needle 12 is thus bent and retracted whereby 
the syringe is rendered non-reusable and incapable of harming anyone. 
It will be readily appreciated that this invention is operable to modify an 
otherwise conventional syringe so as to effectively limit the use of the 
syringe to a single use, and also to render the syringe, after use, 
incapable of harming anyone. A simple construction is utilized for 
concurrently bending and retracting the needle with a simple manual 
manipulation of the syringe. 
Since many changes and variations of the disclosed embodiments of the 
invention may be made without departing from the inventive concept, it is 
not intended to limit the invention otherwise than as required by the 
appended claims.