摘要 |
A device for lubricating rotary drill bits of the type comprising a roller cutter (14) which is rotatably carried by means of a bearing system (15, 16, 17, 18). Fluid is supplied to the bearing system for cooling thereof through a cooling passage (31, 32, 33; 51, 61), and a lubricant is delivered to the cooling passage from a lubricant reservoir (36; 46) through a lubricating passage (40; 54). For purposes of controlling the supply of lubricant the outlet of the lubricating passage into the cooling passage is arranged axially behind the inlet of the lubricating passage in the lubricant reservoir.
|