Abstract: The syringe includes a barrel, a plunger, and an adapter for mounting the needle in the distal end of the barrel. The adapter includes a protrusion projecting away from the needle end and into the barrel defining an annular space between the barrel and the protrusion. The plunger and protrusion have complementary surfaces whereby the plunger may grip the adapter for removal of the adapter into the interior of the barrel after use. These complementary surfaces afford initial resistance to further axial movement of the plunger toward the adapter, signalling the user that further axial pressure will permanently lock the plunger and adapter to one another whereby, upon application of full axial pressure on the plunger, the complementary surfaces of the plunger and adapter permanently lock to one another to enable joint unitary movement of the plunger and adapter together with the needle carried by the adapter into the barrel.

Abstract: The syringe includes a barrel, a plunger, and an adapter for mounting the needle in the distal end of the barrel. The adapter includes a protrusion projecting away from the needle end and into the barrel defining an annular space between the barrel and the protrusion. The plunger and protrusion have complementary surfaces whereby the plunger may grip the adapter for removal of the adapter into the interior of the barrel after use. These complementary surfaces afford initial resistance to further axial movement of the plunger toward the adapter, signalling the user that further axial pressure will permanently lock the plunger and adapter to one another whereby, upon application of full axial pressure on the plunger, the complementary surfaces of the plunger and adapter permanently lock to one another to enable joint unitary movement of the plunger and adapter together with the needle carried by the adapter into the barrel.

Abstract: The syringe includes a plunger and an adapter carrying a needle, the adapter being threaded into the end of the barrel for withdrawal, upon connection with the plunger and together with the needle, into the interior of the barrel. To prevent the adapter from unseating from the barrel end before or during use, the needle guard and hub are connected to enable axial pressure from the needle guard to be transmitted through the hub to the adapter to attach the hub to the adapter. Cooperating surfaces on the needle guard and needle hub are engageable to enable a torque to be applied to the adapter only in a direction opposite to the direction of rotation of the adapter during unseating. To the extent rotation of the needle guard in the opposite direction applies a torque to the adapter, that torque is insufficient to unseat the adapter from the barrel end.

Abstract: The syringe includes a barrel, a plunger, and an adapter for mounting the needle in the distal end of the barrel. The adapter includes a protrusion projecting away from the needle end and into the barrel defining an annular space between the barrel and the protrusion. The plunger and protrusion have complementary surfaces whereby the plunger may grip the adapter for removal of the adapter into the interior of the barrel after use. The adapter includes vent passages communicating between the central passage through the adapter and the annular space whereby air can be vented from the barrel after receiving fluid within the barrel and prior to injection. Thus, the syringe may be oriented in a vertical position needle end uppermost with the vent passages forming the most superior portion of the barrel interior whereby air may be vented.

Abstract: The syringe includes a barrel, a plunger, and an adapter for mounting the needle in the distal end of the barrel. The adapter includes a protrusion projecting away from the needle end and into the barrel defining an annular space between the barrel and the protrusion. The plunger and protrusion have complementary surfaces whereby the plunger may grip the adapter for removal of the adapter into the interior of the barrel after use. The adapter includes vent passages communicating between the central passage through the adapter and the annular space whereby air can be vented from the barrel after receiving fluid within the barrel and prior to injection. Thus, the syringe may be oriented in a vertical position needle end uppermost with the vent passages forming the most superior portion of the barrel interior whereby air may be vented.

Abstract: This invention relates to a safety syringe needle device which has medical and industrial application. More particularly, this invention pertains to a syringe which, after being used by a person to inject medication or fluid into a patient, or in sampling or exposure to toxic materials, or the like, can be transformed by the person to withdraw the needle into the barrel of the syringe for disposal purposes, thereby eliminating needle stick injuries among such persons.

Abstract: The syringe includes a barrel, a plunger, and an adapter for mounting the needle in the distal end of the barrel. The adapter includes a protrusion projecting away from the needle end and into the barrel defining an annular space between the barrel and the protrusion. The plunger and protrusion have complementary surfaces whereby the plunger may grip the adapter for removal of the adapter into the interior of the barrel after use. The adapter includes vent passages communicating between the central passage through the adapter and the annular space whereby air can be vented from the barrel after receiving fluid within the barrel and prior to injection. Thus, the syringe may be oriented in a vertical position needle end uppermost with the vent passages forming the most superior portion of the barrel interior whereby air may be vented.

Abstract: This invention relates to a safety syringe needle device which has medical and industrial application. More particularly, this invention pertains to a syringe which, after being used by a person to inject medication or fluid into a patient, or in sampling or exposure to toxic materials, or the like, can be transformed by the person to withdraw the needle into the barrel of the syringe for disposal purposes, thereby eliminating needlestick injuries among such persons.