Injection molding machine

An injection molding machine, comprising:

• a first friction member;
• a second friction member, the first and second friction members being connected to move relative to each other;
• a screw coupled to one of the first friction member and the second friction member;
• a base;
• a plasticizing motor coupled to the other of the first friction member and the second friction member, the plasticizing motor configured to rotate the screw, the plasticizing motor not being movable relative to the base;
• an expandable/retractable member provided in a periphery of the first and second friction members and including first and second end parts;
• a first attachment member attached to the first end part;
• a second attachment member attached to the second end part, one of the first and second attachment members being fixed to the base, the other of the first and second attachment members being movable with respect to the base along an axial direction of the screw;
• and
• an injection motor configured to move the screw with respect to the base by way of the one of the first and second friction members coupled to the screw, the injection motor being fixed to the other of the first and second attachment members movable with respect to the base along the axial direction of the screw, the injection motor being configured to move together with the other of the first and second attachment members movable with respect to the base along the axial direction of the screw,
• wherein a lubricating oil is fed to an area between first and second friction members,
• wherein a position of the second attachment member relative to the first attachment member is displaced in cooperation with a position of the second friction member relative to the first friction member,
• wherein the expandable/retractable member is configured to form a reservoir space that stores the lubricating oil in the periphery of the first and second friction members,
• wherein the expandable/retractable member is configured to expand/retract in correspondence with an interval between the first and second attachment members.