Automatic mixing and injecting apparatus

摘要

An automatic mixing and injecting apparatus comprises a syringe assembly within a housing. The syringe assembly has a chamber for holding a liquid, which can be a liquid medicine or a solvent. A second chamber may hold a dry medicine. The second chamber is releasably sealed with respect to the first chamber. A spring-operated plunger forces liquid from the first chamber and causes the releasable seal to disengage when the needle has entered the recipient. At this time, the liquid flows through the second chamber and dissolves any dry medicine in that chamber. A releasable coupling disengages the plunger from the driver spring and allows the plunger, syringe, and needle to retract under the urging of a return spring.