ROTATING MEMBER, ROTATING SHAFT MEMBER, FIXING ROLLER OF IMAGE FORMING DEVICE, CYLINDRICAL MEMBER, MANUFACTURE OF ROTATING SHAFT MEMBER, AND MANUFACTURE OF DEVELOPING SLEEVE OF IMAGE FORMING DEVICE

摘要

PROBLEM TO BE SOLVED: To prevent the cracking in welding by forming a space part between the butt surfaces of a cylindrical member to a closing member and welding the circumference of the butt surfaces. SOLUTION: Each recessed part 2D, 4D of a cylindrical member 2 and a shaft member 3 forms a ring space D by the butting of the cylindrical member 2 to the shaft member 4. The temperature by the laser beam emitted to a welding member is extended to the vicinity of the emitting part of the cylindrical part and the shaft part, but the extension of the temperature receives the heat insulating effect by the air in the space part D. Although the welding part is cracked by the expansion and contraction of volume of this pat when the space D is absent, the sudden volume contraction of the welding part can be moderated by the warmed air in the space part D when the space D is provided, whereby the cracking can be suppressed.