Patent ID: 8251951

Claim:
An injection needle cartridge comprising: a substantially columnar retaining member for retaining an injection needle axially penetrating therethrough so that the injection needle projects from both end surfaces thereof; a first holder member having a first bottom plate facing to one end surface of the retaining member and a first slider section erected from the first bottom plate so as to be in contact with the outer peripheral side surface of the retaining member to hold the retaining member; a second holder member having a second bottom plate facing to the other end surface of the retaining member and a second slider section erected from the second bottom plate so as to be in contact with the outer peripheral side surface of the retaining member to hold the retaining member, wherein the second holder member is configured to contain the retaining member in a containing space formed by the first bottom plate and the second bottom plate oriented to face to each other, and to be rotatable relative to the first holder member about the axis of the retaining member; and a substantially cylindrical inner ring constituting a rotation restricting mechanism for restricting the relative rotation of the paired holder members about the axis of the retaining member in a state of being placed around the retaining member and positioned on the inner periphery side of the first slider section or the second slider section, wherein the containing space is axially retractable in the state in which the slider sections are alternately displaced along the outer periphery of the retaining member to allow the injection needle of the retaining member to penetrate through and to project from the bottom surface plates to be capable of an injection, and wherein the containing space is axially extendable to place the injection needle in the containing space after the injection, in which the cylindrical inner ring is configured to, (i) allow the first and second holder members to rotate relative to each other to a position where the extreme end faces of the slider sections of the first and second holder members face to each other, and then (ii) restrict the relative rotation of the first and second holder members in said position.