YASKAWA SGD7S Product Manual page 187

5.14 Electronic Gear Settings
5.14.2 Electronic Gear Ratio Setting Examples
*1.
These are reference values for setting SERVOPACK parameters. Contact the manufacturer for actual linear
encoder scale pitches.
*2.
This is the model of the Serial Converter Unit.
*3.
This is the model of the Head with Interpolator.
*4.
This is the model of the Interpolator.
*5.
If you use an encoder pulse output with this linear encoder, the setting range of the encoder output resolution
(Pn281) is restricted. Refer to the following section for details on the encoder output resolution (Pn281).
Information
5.14.2 Electronic Gear Ratio Setting Examples
Setting examples are provided in this section.
• Rotary Servomotors
Step
1
2
3
4
5
6
5-44
6.5.2 Setting for the Encoder Divided Pulse Output on page 6-14
Resolution
You can calculate the resolution that is used inside the SERVOPACK (i.e., the travel distance per
feedback pulse) with the following formula.
Resolution (travel distance per feedback pulse) =
The SERVOPACK uses feedback pulses as the unit to control a Servomotor.
Linear encoder pitch
Description
Encoder:
24 bits
• Ball screw lead: 6 mm
Machine
• Gear ratio: 1/1
Specifications
Encoder Resolution 16,777,216 (24 bits)
0.001 mm (1 μm)
Reference Unit
Travel Distance per
6 mm/0.001 mm =
Load Shaft Revolution
6,000
(Reference Units)
B
Electronic Gear Ratio
A
Pn20E: 16,777,216
Parameters
Pn210: 6,000
Resolution of Serial Converter Unit or linear encoder
Linear encoder pitch
=Distance for one cycle of the analog voltage
feedback signal from the linear encoder
Machine Configuration
Ball Screw
Reference unit: 0.001 mm
Load shaft
Ball screw lead:
Load shaft
6 mm
• Rotation angle per revo-
lution: 360°
• Gear ratio: 1/100
16,777,216 (24 bits)
0.01°
360°/0.01° = 36,000
16,777,216 1 B
×
= =
6,000 1 A
Pn20E: 167,772,160
Pn210: 3,600
Linear encoder pitch
Rotary Table Belt and Pulley
Reference unit: 0.005 mm
Reference unit: 0.01°
Gear ratio:
1/100
Gear ratio:
1/50
Encoder: 24 bits
• Pulley dia.: 100 mm
(Pulley circumference:
314 mm)
• Gear ratio: 1/50
16,777,216 (24 bits)
0.005 mm (5 μm)
314 mm/0.005 mm =
62,800
B
16,777,216 100
×
=
A
36,000 1
Pn20E: 838,860,800
Pn210: 62,800
Load shaft
Pulley dia.:
100 mm
Encoder: 24 bits
16,777,216 50
×
62,800 1