Needle-equipped outer cylinder and method for manufacturing the same

A method for manufacturing a needle-equipped outer cylinder, the method comprising:

• providing a needle tube;
• providing a joining member comprising:
• a needle tube accommodation hole for accommodating the needle tube,
• a joining outer peripheral portion provided on an outer peripheral portion of the needle tube accommodation hole, and
• an abutment portion located at a proximal end portion of the joining member, the abutment portion comprising a rib formed on the proximal end portion of the joining member and extending in a proximal end direction;
• providing an outer cylinder member comprising:
• a distal end joint that comprises an inner cavity configured to receive the joining outer peripheral portion of the joining member, and
• a projection located at a proximal end portion of the inner cavity and projecting into the inner cavity;
• assembling the needle tube, the joining member, and the outer cylinder member such that the needle tube is inserted into or inserted into and fixed to the needle tube accommodation hole of the joining member, the joining member is inserted into the distal end joint of the outer cylinder member, and the abutment portion of the joining member abuts the projection of the outer cylinder member;
• and
• heat-welding the joining outer peripheral portion of the joining member to an inner peripheral surface of the distal end joint of the outer cylinder member and an outer peripheral surface of the needle tube by causing the needle tube to generate heat by a heat generating device while pressing a distal end portion of the joining member in a proximal end direction of the joining member by a pressing member.