| abstract |
The present invention relates to a gear pump or the like able to effectively prevent excess heat generation between a gear shaft and a journal bearing. A gear pump (1) that lubricates gear shafts (14, 15) on which gears (12, 13) are attached and journal bearings (62, 63) that rotatably support the gear shafts (14, 15) with an ultraviolet-curable ink that is a transport target, in which a width diameter ratio that is a ratio of a bearing length of the journal bearings (62, 63) to the shaft diameter of the gear shafts (14, 15) is 0.5 to 2.0, and a clearance ratio that is a ratio of a radial clearance between the gear shafts (14, 15) and the journal bearings (62, 63) to the shaft radius of the gear shafts (14, 15) is 0.0009 to 0.01. |