Puncture instrument, puncture needle cartridge mounted in puncture instrument, and method for using puncture instrument and puncture needle cartridge

A puncture instrument having a first end side, which is the side on which a puncture needle cartridge is mounted, and a second end side opposite the first end side, said puncture instrument comprising:

• an elongated main case including an opening on the first end side and on the second end side;
• a main rod provided in the main case;
• an injector rod mounted to the main rod and including a lancet holder on the first end side;
• an actuating rod mounted to the injector rod and including an engagement component on the second end side;
• a first biasing member configured to bias the injector rod toward the first end side;
• a manipulation component provided slidably in and out of the opening on the second end side of the main case;
• and
• a locking member rotatably supported by a portion of the main rod between the injector rod and the manipulation component, the locking member including a first engaged part configured to engage the engagement component of the actuating rod, a second engaged part configured to abut a portion of the manipulation component on the first end side, and a second biasing member configured to bias the first engaged part toward the engagement component,
• wherein the manipulation component has on the first end side thereof a flat part configured to abut the second engaged part of the locking member, and an inclined part adjacent to the flat part, the inclined part extending to the second end side and being inclined to an axis of the main case,
• the locking member rotates by an action of mounting the puncture needle cartridge so that the second engaged part rotates from a position opposite the flat part of the manipulation component to a position opposite the inclined part;
• and
• the locking member abuts the flat part when the manipulation component is pushed by an action of disposing the puncture needle cartridge so that the locking member slides toward the first end side with the main rod and the puncture needle cartridge is disposed.