Specifications

4 - 3

Unit setting

Set the unit used for defining positioning operations. Choose from the following units

depending on the type of the control target: mm, inch, degree, and pulse.

(Example) mm, inch......X-Y table, Conveyor

(Select mm or inch depending on the machine specifications.)

degree .........Rotating body (360 degrees/rotation)

pulse ............X-Y table, Conveyor

Each axis unit can be set individually.

Movement amount per pulse

These parameters define the amount of movement achieved by each single pulse

within a pulse train output by the QD75.

(The following explanations are made using mm as the unit.)

PLC CPU

QD75

MR-H

MR-J2S

MR-C

Workpiece

Pulse

generator

PLC Servo amplifier Servomotor

Reduction

gear

L: Worm gear lead (mm/rev)

R: Deceleration rate

n: No. of pulses from generator (pulse/rev)

Figure4.1 Movement amount per pulse

(1) No. of pulses per rotation (Ap)

The number of pulses (n) generated from the generator is fed back to the servo

amplifier MR-H or MR-J2S.

Ap=n

(2) Movement amount per rotation (A

)

How much the workpiece moves per one motor rotation is determined by the

mechanical structure.

=L R

(3) Unit magnification (Am)

The movement amount per rotation is basically within the set range, however, if

this set range can be exceeded with the magnification multiplied.

"Movement amount per rotation" and "Unit magnification" setting

• Lead of ball screw is 10mm (10000µm), gear ratio is

• As the setting range of "movement amount per rotation" is from 0.1 to 6553.5µm,

set as "1000.0".

• Set the "unit magnification" to "10".