Pharmaceutical cartridge holding unit, and pharmaceutical injection device provided therewith

1. A pharmaceutical cartridge holding unit which holds a pharmaceutical-filled cartridge and is configured to be mounted to a pharmaceutical injection device main body, in order to mount the pharmaceutical-filled cartridge to a pharmaceutical injection device, the pharmaceutical cartridge holding unit comprising:

an outer peripheral cap having a front end side opening and a rear end side opening; and

a cartridge cover on an inside of the outer peripheral cap, the cartridge cover being configured to slide forward and backward with respect to the outer peripheral cap, and the cartridge cover including a guided part protruding outward therefrom,

wherein the outer peripheral cap has:

a guide component including risers with respective recesses defined therein, the guide component being 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 in a state of the pharmaceutical cartridge holding unit being separated from the pharmaceutical injection device main body; and

an engagement component that can engage with the pharmaceutical injection device main body; and

wherein the guided part is sandwiched between the risers and is configured to be guided forward and backward within the recesses.

2. The pharmaceutical cartridge holding unit according to claim 1 ,

wherein the engagement component is a first engagement component and the cartridge cover has:

a pharmaceutical cartridge holder that is cylindrical and holds the pharmaceutical-filled cartridge;

a piston insertion component that is on a rear end side of the pharmaceutical cartridge holder and is configured to receive a piston configured to push out the pharmaceutical inside the pharmaceutical-filled cartridge;

an injection needle mounting component on a front end side of the pharmaceutical cartridge holder; and

a second engagement component that can engage with the pharmaceutical injection device main body.

3. A pharmaceutical injection device, comprising:

the pharmaceutical cartridge holding unit according to claim 2 ;

a main body case having the pharmaceutical cartridge holding unit mounted to a front end side of the main body case;

an inner case that is inside the main body case and can slide with respect to the main body case;

a piston that is inside the main body case;

a first driver configured to drive the piston forward and backward with respect to the main body case; and

a second driver configured to drive the inner case forward and backward with respect to the main body case,

wherein the main body case has a first engaged part configured to engage the first engagement component of the outer peripheral cap, the first engaged part being on a front end side of the main body case, and

wherein the inner case has a second engaged part configured to engage the second engagement component which is on a rear end side of the cartridge cover, the second engaged part being on a front end side of the inner case.

4. The pharmaceutical injection device according to claim 3 ,

wherein the cartridge cover has a holder that removably holds the pharmaceutical-filled cartridge.

5. The pharmaceutical cartridge holding unit according to claim 1 ,

wherein the cartridge cover has a holder that removably holds the pharmaceutical-filled cartridge.

6. The pharmaceutical cartridge holding unit according to claim 1 ,

wherein the guide component is groove-shaped and defined along forward and backward directions so as to have a length that is greater than a width of the guided part in forward and backward directions, and

wherein the stopper is on a front end and a rear end of the guide component, and is configured to come into contact with the guided part to prevent the cartridge cover from coming loose from the outer peripheral cap.