JPS5938822B

PURPOSE:To prevent the outflowing of grease from bearings by air pressure of a driving chamber by providing to the coater body a communication path by which the air balance between the driving chamber of bearings for a rotary shaft and the opposite side portion of the driving chamber. CONSTITUTION:Compressed air is sent through a pipe for an air-driven motor from a high-pressure air generator to the nozzle 24 of an electrostatic coater body 3 so as to turn a blade with high speeds 5 inside a driving chamber 4, whereby a rotary cup 1 is turned with high speeds through a rotary shaft 2. A bearing 6 for the rotary shaft 2 is provided between the rotary shaft 2 and the coater body 3, an air trapping chamber 7 is formed between the rotary shaft 2 and the coater body 3 in a position opposite to the driving chamber 4 of the bearing 6, and a communication path 8 is formed between the driving chamber 2 and the air trapping chamber 7. Thus, the pressure of the driving chamber 4 is balanced with that of the air trapping chamber 7 by the communication path 8, and the outflowing of grease from the bearing 6 by the pressure of the driving chamber 4 can therefore be prevented.