| 摘要 |
A vacuum pump (50) comprises a casing and an impeller located in the casing, the impeller comprising a shaft (52) supported by a bearing arrangement for rotation relative to the casing. To supply lubricant to a rolling bearing (64) of the bearing arrangement, a droplet ejection unit (82) is located in the casing for ejecting droplets of lubricant towards the bearing. The ejection unit (82) comprises a lubricant chamber (104), a nozzle (124) in fluid communication with the chamber (104), and an electrically actuable actuator (102), such as a piezoelectric or a magnetostrictive element. A controller (140) applies electrical signals to the actuator to effect ejection of droplets of lubricant from the chamber through the nozzle (124) directly on to the bearing (64). This can enable a controlled amount of lubricant to be supplied directly to the bearing as required and at any preferred rate. |
