Patent attributes
A pharmaceutical cartridge holding unit holds a pharmaceutical cartridge and is mounted to a pharmaceutical injection device main body in order to mount the pharmaceutical cartridge to a pharmaceutical injection device. The pharmaceutical cartridge holding unit comprises an outer peripheral cap having a front end side opening and a rear end side opening, and a cartridge cover that is on an inside of the outer peripheral cap and is held in a state of being able to slide forward and backward with respect to the outer peripheral cap. The outer peripheral cap has a guide component configured to guide sliding of the cartridge cover forward and backward, a stopper configured to prevent the cartridge cover from coming loose from the outer peripheral cap, and an engagement component that can engage with the pharmaceutical injection device main body.