Method for producing roller member, roller-member mold, roller shaft, and roller member

A method for producing a roller member by inserting a roller shaft into a mold having a first mold surface that defines an outer circumference of a roller portion, a second mold surface that defines a first flat portion of the roller portion, and a third mold surface that defines a second flat portion of the roller portion, by closing the mold, and by injecting a molding material around the roller shaft to integrally mold the roller portion to the roller shaft, the method comprising the steps of:

• inserting the roller shaft that has a cut portion including first and second flange portions at portions respectively corresponding to the first and second flat portions into the mold and closing the mold in such a way that the second and third mold surfaces are respectively brought into contact with the first and second flange portions and respectively deform the first and second flange portions;
• and
• injecting the molding material for the roller portion into a cavity defined by the first, second, and third mold surfaces of the mold and the roller shaft.