Dust cover, suspension device, and method for manufacturing dust cover

A method for manufacturing a dust cover including bellows portions that are configured to expand and contract in an axial direction and a flange portion that extends radially outward,

• wherein an inner wall surface of a mold has a recess corresponding to the flange portion, and
• wherein the mold has a variable device that changes an axial dimension of the recess between a primary molding distance and a final molding distance, the final molding distance corresponding to a thickness of the flange portion, and the primary molding distance being larger than the final molding distance,
• the method comprising:
• placing a molten thermoplastic resin having a tubular shape inside the mold in a state where an axial dimension of the recess of the inner wall surface is set to the primary molding distance;
• blowing air into the thermoplastic resin placed inside the mold to deform the thermoplastic resin along the inner wall surface of the mold;
• and
• compressing, in the axial direction, a portion of the thermoplastic resin that enters the recess, by changing the axial dimension of the recess of the inner wall surface to the final molding distance.

A method for manufacturing a substantially cylindrical dust cover configured to cover an outer side of a damper extending in a predetermined direction and including bellows portions that are configured to expand and contract in an axial direction and a flange portion that extends radially outward,

• wherein an inner wall surface of a mold has a recess corresponding to the flange portion, and
• wherein the mold has a variable device configured to change an axial dimension of the recess between a primary molding distance and a final molding distance, the final molding distance corresponding to a thickness of the flange portion, and the primary molding distance being larger than the final molding distance,
• the method comprising:
• placing a molten thermoplastic resin having a tubular shape inside the mold in a state where an axial dimension of the recess of the inner wall surface is set to the primary molding distance;
• blowing air into the thermoplastic resin placed inside the mold to deform the thermoplastic resin along the inner wall surface of the mold;
• and
• compressing, in the axial direction, a portion of the thermoplastic resin that enters the recess by changing the axial dimension of the recess of the inner wall surface to the final molding distance.