|Title:||Medicine injection devices and methods|
|Abstract:|| A reloadable medicine injector and methods are described in which a barrel with a receiving cavity is adapted to slidably receive a syringe subassembly for axial movement therein. Upon removal of a safety and release of a syringe driver, the syringe driver moves forward and injects the syringe needle. A plurality of penetration controls are shown for controlling injection needle penetration depth. The penetration controls have an abutment and various lengths to provide different needle penetration depth positions. In one form of penetration control a sleeve is used against which the syringe or related parts contact. In another form the front return spring is used as a penetration control. A cushioning ring may be used to reduce syringe breakage. A load distribution and guide ring may be used to distribute loading applied to the syringe and help guide the moving syringe.|
|Inventor(s):|| Wyrick; Ronald E. (Spokane, WA) |
|Assignee:|| Washington Biotech Corporation (Spokane, WA) |
|Filing Date:||Oct 09, 2007|
|Claims:||1. A medicine injection device system, comprising: a tube having a muzzle end; a syringe subassembly cavity within the tube; a syringe subassembly within the tube and sized to slide within the cavity, the syringe subassembly having a reservoir containing fluid medication, a needle, and a plunger for forcing the fluid medication from the reservoir through the needle; a driver for forcing the syringe subassembly to penetrate flesh and displace fluid medication through the needle, the driver being movable between a cocked position and extended positions; a penetration control element which controls penetration of the needle to a depth stop position to provide a desired final penetration depth; the penetration control element being configured to be entirely contained in the tube and to encircle the needle; the penetration control element comprising a coil spring selected from a series of coil springs of different winding configurations with different compressed axial lengths, at least some of the coil springs of said series having three or more complete dead windings; the selected coil spring being positioned in the cavity to be engaged and compressed by the syringe subassembly to its contracted axial length in response to movement of the syringe subassembly, to thereby stop movement of the syringe subassembly at a selected stop position with the needle at a selected needle penetration depth; the selected coil spring having at least three complete dead windings. |
2. The system of claim 1 wherein the tube comprises a barrel and a removable nose cap joined to the barrel, and wherein the selected coil spring engages the nose cap for removal therewith.
3. The system of claim 1 wherein the tube comprises a barrel and a removable nose cap releasably attached to the barrel and abutting an end of the selected coil spring.
4. A device for injecting fluid medicine, comprising: a tube having a muzzle end with a needle receiving aperture, a syringe subassembly cavity within the tube; a syringe subassembly within the tube and sized to slide within said cavity, the syringe subassembly having a reservoir containing the fluid medicine, and having a flesh penetrating needle operably joined to the reservoir so that the fluid medicine from the reservoir may be dispensed through the flesh penetrating needle; a trigger mechanism configured to transition the syringe subassembly from a non-deployed state in which the flesh penetrating needle is entirely contained within the tube to a deployed state in which the flesh penetrating needle extends outwardly through the needle receiving aperture; the syringe subassembly sliding within the tube in transitioning between the deployed and non-deployed states; a return mechanism configured to transition the syringe subassembly from the deployed state back to the non-deployed state; the return mechanism including a coil spring that encircles the flesh penetrating needle when the syringe subassembly is in the non-deployed state; said coil spring of the return mechanism being entirely contained in the tube; and a penetration control element which controls penetration of the flesh penetration needle to a depth stop position to provide a desired final penetration depth; the penetration control element being a rigid sleeve that encircles the coil spring of the return mechanism when the syringe subassembly is in the deployed and non-deployed states, the rigid sleeve being entirely contained in the tube and being a separate piece from the tube; the rigid sleeve having a first surface adjacent the muzzle end of the tube, and having an abutment surface in opposing relation to the first surface; the syringe subassembly having a surface which contacts the abutment surface in the deployed state, and the abutment surface thereby limiting the distance that the syringe subassembly can slide down the tube as it is transitioned to the deployed state; the abutment surface of the rigid sleeve being spaced from the first surface of the rigid sleeve by a length which sets the distance that the flesh penetration needle extends outwardly of the tube in the deployed state.
5. The device of claim 4 wherein the surface of the syringe subassembly that contacts the abutment surface is a surface of an annular load distributer.
6. The device of claim 5 wherein the annular load distributer is formed of stainless steel.
7. The device of claim 4 wherein the rigid sleeve is a plastic sleeve.
8. The device of claim 4 wherein the tube is a barrel joined to a nose cap; and wherein the rigid sleeve comprises a flange configured to secure the coil spring of the return mechanism to the nose cap.
9. The device of claim 4 wherein the syringe subassembly includes a plunger within the reservoir and configured to push the fluid medicine from the reservoir during the dispensing of the fluid medicine through the flesh penetrating needle; the device further comprising a plunger rod connected to the plunger, with said plunger rod comprising two axially adjustable segments threadedly engaged to one another.
10. The device of claim 9 further comprising a dosage control collar extending partially around the plunger rod.