Hole measuring method for bearing bush of fluid dynamic bearing system, involves positioning shaft relative to hole in bush, and determining value describing measurement of fluid path from rotational speed of bush and shaft

摘要

The method involves positioning a shaft (10) relative to a hole in a bush (18) such that a fluid gap (16) is formed between the shaft and the bush. A fixed brake bush is arranged such that the brake bush concentrically surrounds the bush by forming another fluid gap (20) with a preset measurement. The shaft is rotatably driven with preset rotation speed relative to the bush. Adjusted speed (nb) of the bush and speed (nw) of the shaft are measured. A value describing measurement of the one of the fluid paths is determined from the rotational speed of the bush and the shaft. An independent claim is also included for a device for measuring a hole in a bush.