Retractable needle assembly utilizing a standard interface and syringe utilizing the same

1. A single-use injection device comprising:

a barrel;

a plunger having a portion structured and arranged to move within the barrel and a frangible member arranged within the plunger at a location that is axially spaced from a proximal end of the plunger;

a needle connecting arrangement that comprises a needle connecting interface adapted to mate with a needle interface, a biasing member, and a body; and

said body one of:

containing at least one deflectable member movable between an initial position and a position allowing the needle connecting interface to retract into the barrel under action of the biasing member;

being capable of being installed on the barrel by a user prior to use; and

being capable of being non-removably connected with the barrel by a user.

2. The injection device of claim 1 , wherein the plunger is a hollow plunger.

3. The injection device of claim 1 , wherein the plunger comprises a piston arranged at a proximal area of the plunger and an actuating end arranged in front of the piston.

4. The injection device of claim 3 , wherein the plunger further comprises at least one of:

the piston being an elastomer or rubber piston;

a hollow space sized and configured to receive therein an injection needle; and

a locking member adapted to lock with a locking member arranged on the barrel.

5. The injection device of claim 1 , wherein the barrel and the plunger each comprise a synthetic resin material.

6. The injection device of claim 1 , wherein the at least one deflectable member of the body comprises at least one releasable retaining member.

7. The injection device of claim 6 , wherein the at least one releasable retaining member comprises plural radially oriented releasable retaining members.

8. The injection device of claim 1 , wherein the at least one deflectable member of the body comprises at least one deflectable retaining member.

9. The injection device of claim 8 , wherein the at least one deflectable retaining member comprises plural radially oriented releasable retaining members.

10. The injection device of claim 1 , further comprising at least one of:

a locking arrangement that is structured and arranged to lock a portion of the needle connecting arrangement to a portion of the plunger;

a locking arrangement selectively locking a portion of the plunger to the barrel upon the plunger reaching a substantially fully depressed position.

11. The injection device of claim 1 , wherein, when the plunger is moved to a full injection position, a member arranged within the needle connecting arrangement and coupled to the needle connecting interface is automatically caused to retract into the plunger.

12. The injection device of claim 1 , wherein, when the plunger is moved to a full injection position, a member arranged within the needle connecting arrangement is automatically caused to retract into the barrel.

13. The injection device of claim 1 , further comprising a system providing an indication to the user in regards to a depressed position of the plunger.

14. The injection device of claim 1 , further comprising a system providing an indication to the user that at least one of:

the plunger has reached a full injection position; and

the further forward movement of the plunger will cause a member coupled to a needle to automatically retract into the plunger.

15. A method of using the injection device of claim 1 , the method comprising:

installing a needle member having a needle and a connecting interface on the injection device; and

moving the plunger relative to the barrel so as to cause medicine to exit through the needle,

wherein the needle member is capable of retracting into the plunger.