Patent ID: 6645179
Filing Date: 2003-11-11
Classification: A61M

Abstract:
An injection syringe comprising a multichambered cylindrical ampule; a tripartite case having a front case, a middle case, a rear case, and a needle holder; and a plunger, wherein:the multichambered cylindrical ampule includes at least two chambers of a front space and a rear space, the front space being sealed forwardly with a packing penetrable by a needle an sealed rearwardly with a movable front gasket, and the rear space being sealed forwardly with the front gasket and sealed rearwardly with a movable rear gasket, and the ampule further including a bypass route longitudinally arranged on an inner surface of the ampule such that the front gasket is located to take a position rearwardly from the bypass route before dissolution of a solid medicine, such that the front space, which is configured to receive a solid medicine, is separated from the rear space, which is configured to receive a medicinal solvent or dispersing agent, thereby the solid medicine and the solvent or dispersing agent being separately stored; the front case includes a tapered tip portion configured to fix a front edge of the ampule inside thereof, and a first fixer device provided externally at a rear end thereof; the middle case including a second fixer device provided internally at a front end thereof, and a flange provided internally at the rear end thereof to fixedly accommodate the ampule inside a housing formed of the front case and the middle case by tightening the first and second fixer devices; the middle case further includes a third fixer device provided externally at midportion thereof, and the rear case including a fourth fixer device provided internally at a front end thereof and also a plunger retainer provided internally at a rear end thereof the plunger being mounted in place by the plunger retainer and engaged at a front end of the plunger with a rear gasket; whereby, in a process of dissolving the solid medicine, pushing on the rear case toward the front of the ampule causes the front gasket and the rear gasket in unison to advance with aid of abutment at a shoulder provided at midportion of the plunger; upon the front gasket's entry into a bypass route zone, the solvent or dispersing agent stored in the rear space starts flowing into the front space through the bypass route and an injection is prepared after the medicine has been dissolved or dispersed; then, tightening the third and fourth fixer devices to connect the middle case with the rear case avoids a reverse move of the shoulder with aid of the retainer to keep the injection at a complete status, and pushing on the rear end of the plunger performs the injection through the needle holder; thereby completing the injection with use of an unstable injection.