Functions And Configuration - Mitsubishi Electric MR-J4-10B(-RJ) Instruction Manual

15. USING A DIRECT DRIVE MOTOR
15. USING A DIRECT DRIVE MOTOR
CAUTION

15.1 Functions and configuration

15.1.1 Summary
The fields of semiconductor/LCD manufacturing systems, mounters, and others have strong demands for
high accuracy and efficiency. Therefore, the number of systems using a direct drive motor for a drive axis
has been increasing. The direct drive servo system includes the following features.
(1) Performance
(a) The direct drive servo system ensures the high-rigidity and the high-torque. A high-resolution
encoder enables the high-accuracy control.
(b) The high-resolution encoder contributes to the high-indexer accuracy.
(c) Since reducer is no longer required, no backlash occurs. In addition, the settling time is reduced, and
the high-frequency operation is enabled.
(d) Since reducer is no longer required, the motor does not deteriorate with time by reducer.
(2) Mechanism
(a) The motor's low profile design contributes to compact moving part of the machine and a low center
of gravity for enhanced equipment stability.
(b) The motor has an inner rotor with hollow shaft which enables cables and pipes to be passed
through.
(c) Lubrication and the maintenance due to abrasion are not required.
The following shows the differences between the direct drive motor and the rotary servo motor.
Category
External I/O signal FLS (Upper stroke limit),
RLS (Lower stroke limit)
Motor pole Magnetic pole detection
adjustment
Absolute position Absolute position encoder
detection system battery
Absolute position storage
unit (MR-BTAS01)
When using the direct drive motor, read the "Direct Drive Motor Instruction
Manual".
POINT
Refer to section 1.4 for the software version of a servo amplifier that is
compatible with the direct drive servo system.
Item
Direct drive motor
Required
(for magnetic pole
detection)
Required
Required
Required
Differences
Rotary servo motor
Not required
Not required
(default setting)
Required
Not required
15 - 1
Remark
Automatically turns on in the
parameter setting.
Automatically executed at the first
servo-on after the power is turned
on.
For the absolute position detection
system, [Pr. PL01] can disable the
magnetic pole detection. (Refer to
(3) (a) of section 15.3.2.)