Drive device, image forming apparatus, and grease composition
A drive device includes a slide bearing; a shaft that passes through the slide bearing; a gear that is fixed to the shaft; and a grease composition that is held in a clearance between the slide bearing and the shaft. At least one of the slide bearing and the shaft is made of a resin. The clearance is in a range of 10 to 110 μm. The grease composition contains a hydrocarbon base oil and lithium soap serving as a thickener. A weight ratio of the hydrocarbon base oil to the lithium soap is in a range of 94.5:5.5 to 96.0:4.0. A consistency of the grease composition is in a range of 360 to 400.
1. A drive device comprising:
a slide bearing;
a shaft that passes through the slide bearing;
a gear that is fixed to the shaft; and
a grease composition that is held in a clearance between the slide bearing and the shaft, wherein
at least one of the slide bearing and the shaft is made of a resin,
the clearance is in a range of 10 to 110 μm,
the grease composition contains a hydrocarbon base oil and lithium soap serving as a thickener,
a weight ratio of the hydrocarbon base oil to the lithium soap is in a range of 94.5:5.5 to 96.0:4.0, and
a consistency of the grease composition is in a range of 360 to 400.
2. The drive device according to claim 1 , wherein one of the slide bearing and the shaft is made of a metal or an alloy.
3. The drive device according to claim 2 , wherein the shaft is made of a stainless steel or a free-cutting steel.
4. The drive device according to claim 1 , wherein the slide bearing is made of a polyacetal resin.
5. The drive device according to claim 1 , wherein a kinetic viscosity of the hydrocarbon base oil is equal to or smaller than 20 mm2/s at 40□ C.
6. The drive device according to claim 1 , wherein the grease composition contains olefin resin powder.
7. The drive device according to claim 1 , wherein the grease composition is held on a tooth flank of the gear attached to the shaft and a tooth flank of another gear engaged with the gear attached to the shaft.
8. The drive device according to claim 1 , wherein the grease composition held in the clearance contains a styrene thickener.
9. An image forming apparatus, comprising the drive device according to claim 1 .
10. A grease composition used for the drive device according to claim 1 .