
2.SPINDLE DESIGNING AND MOTOR MOUNTING B-65342EN/01
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• All the rotor are checked its unbalance in production process. So
normally, it is unnecessary to balance for the rotor after
shrinkage fit, only to balance the whole main shaft. If user needs
more precise balancing of the rotor, the taps on the side ring’s
can be used. The allowable mass is following table. Do not
exceed these value.
Allowable mass [g]
Total mass per one ring For one tap
B132Lx 6 g 2 g
B160Lx 8 g 2 g
• The taps on the side ring is only for the balancing the rotor.
Never use it for the whole balancing of the main shaft.
• Never machine rotor and side ring.
• We recommend to mount the rotor to spindle directly without
sleeve. If customer uses rotor sleeve, the interference should be
taken enough so that the rotor not to slip.
WARNING
Synchronous spindle motor, control soft must
always catch pole position. If it is missed by some
causes, it will be possible to cause uncontrollable
condition. This is very danger.
Therefore, the fixing torque must be taken enough
so that not to slip the rotor.
If the possibility of the slip is happen, for example a
crushing spindle, the spindle must not be restarted
without running pole position detecting function.
• Electro static charge of the spindle :
There is some possibility that electro static voltage is charged on
the spindle. It may be caused by bearing lubricating structure or
cutting condition, and depends on the spindle structure.
Particularly if a ceramic bearing is used, it is obvious. We
recommend to take some structure that the electric potential
voltage becomes equal between the grounded stator core and the
spindle. If no measures are taken, electric discharge will happen
between rotor and stator, or spindle and sensor, and it will be the
cause of some trouble.