Fixing device, image forming apparatus and adjustment of fixing device

1. A fixing device comprising:

a fixing member that is driven to rotate;

a pressurizing member that is rotated in accordance with rotation of the fixing member while pressing the fixing member, and that forms a pressing portion through which a recording medium passes, the pressing portion being formed between the pressurizing member and the fixing member; and

a surface shape adjusting member that has a surface including a plurality of spherical projections and that rotates with the surface being in contact with the fixing member.

2. The fixing device according to claim 1 , wherein the surface shape adjusting member adjusts surface shapes of the fixing member by providing a plurality of spherical recesses to a surface of the fixing member using the plurality of spherical projections while rotating with the surface thereof being in contact with the fixing member.

3. The fixing device according to claim 1 , wherein the projections of the surface shape adjusting member have a maximal diameter of about 10 μm to about 50 μm.

4. The fixing device according to claim 1 , wherein the number of the projections of the surface shape adjusting member is about 100 per square millimeter to about 150 per square millimeter.

5. The fixing device according to claim 1 , wherein the surface shape adjusting member includes:

a base body that is formed of a columnar roll; and

a surface layer that is laminated on a surface of the base body, and that contains fluorine resin and spherical particles having an average particle diameter of about 10 μm to about 50 μm.

6. The fixing device according to claim 5 , wherein the spherical particles contained in the surface layer are alumina particles.

7. The fixing device according to claim 1 , wherein

the fixing member is an endless belt;

the endless belt has a plurality of rolls coming into contact with the endless belt; and

the surface shape adjusting member is located upstream of the pressurizing member in a rotation direction of the endless belt, and is one of the plurality of rolls, the one being closest to the pressurizing member.

8. An image forming apparatus comprising:

a toner image forming unit that forms a toner image;

a transfer unit that transfers, onto a recording medium, the toner image formed by the toner image forming unit; and

a fixing unit that fixes, on the recording medium, the toner image transferred by the transfer unit onto the recording medium,

the fixing unit including:

a fixing roll;

a fixing belt that is laid around the fixing roll;

a pressure roll that forms a pressing portion through which the recording medium passes, the pressing portion being formed between the pressure roll and the fixing belt; and

a surface shape adjusting roll that has a surface including a plurality of spherical projections, and that adjusts surface shapes of the fixing belt by providing a plurality of spherical recesses using the plurality of spherical projections while rotating with the surface thereof being in contact with the fixing belt.

9. The image forming apparatus according to claim 8 , wherein the surface shape adjusting roll includes a surface layer that contains alumina particles having an average particle diameter of about 10 μm to about 50 μm.

10. An adjustment method of a fixing device including: a fixing member that is driven to rotate; a pressurizing member that is rotated in accordance with rotation of the fixing member while pressing the fixing member, and that forms a pressing portion through which a recording medium passes, the pressing portion being formed between the pressurizing member and the fixing member; and a surface shape adjusting member that has a surface including a plurality of spherical projections; the adjustment method comprising:

causing the surface shape adjusting member to rotate with the surface of the surface shape adjusting member being in contact with the fixing member; and

adjusting surface shapes of the fixing member by providing a plurality of recesses on a surface of the fixing member during rotation of the surface shape adjusting member.