Fixing device and image forming apparatus

An image forming apparatus comprising:

• a toner-image-forming section that forms a toner image;
• a transfer section that transfers the toner image to a recording material;
• and
• a fixing section that fixes the toner image on the recording material,
• wherein the fixing section includes
• a pressing member that is rotatably held and provides a pressure acting in one direction;
• a heating member that is rotatably held in such a manner as to face the pressing member and includes a substantially cylindrical member and a heating unit, the substantially cylindrical member receiving the pressure, the heating unit being provided inside the substantially cylindrical member, the heating member fixing a toner image on a sheet with the pressure provided by the pressing member and heat generated by the heating unit;
• a drive source that outputs a driving force with which the heating member is rotated;
• and
• a transmission member that provides a space that receives an end of the substantially cylindrical member with a gap interposed therebetween, the transmission member having an inner circumferential surface that comes into contact with the end of the substantially cylindrical member in the space when the substantially cylindrical member receives the pressure from the pressing member, the transmission member transmitting the driving force of the drive source to the heating member.