CP7 training(6.0) (1).pdf - 第137页
FK-9F98-27 CP-7 Series T raini ng T ext for Service Engineers Edition 6.0 Chapter 1 1. Absolute Encoder Recovery Procedure [4/4] Absolute Encoders Incremental encoders Let’s imagi ne that the resolution of the X-axis mot…
FK-9F98-27 CP-7 Series Training Text for Service Engineers
Edition 6.0 Chapter 11. Absolute Encoder Recovery Procedure [3/4]
CP-742/743E
Axis
Condition
Fn008(Fn013) setting position
If the value is in range, then
OK.
Reference setting
position
1to 6,000
pulses
1 to 6,000 pulses Cam angle 0
degrees C
CAM Original
Pos. in the
Calibration
Data
*1
6,001 to
12,000
pulses
6,001 to 12,000 pulses Cam angle 180
degrees
X 1 to 12,500 pulses + M/S [2,500+/-50]
Y
− 1 to − 12,500 pulses − M/S [− 2,500 +/- 50]
Z
− 1 to − 3,000 pulses − M/S [− 1,000+/- 50]
PQ Any position
FQ Any position
RQ Any position
NC Any position
D1 1 to 8,000 pulses + M/S [5000+/-50]
D2
− 1 to − 8,000 pulses − M/S [− 5000 +/- 50]
NZ
− 1 to −3,000 pulses
Push [0+/- 50] from
− M/S
*1) When the CAM original Pos. is at minus position (e.g.: − 500pulse), calculation is 12,000 + Original
Pos.(12,000+ (− 500) =11,500). Use the 11,500 to find the setting position.
Fuji Machine Mfg. Co., Ltd. (Okazaki)
SMT Equipment Quality Assurance Dept.
CS Section
11-
3
FK-9F98-27 CP-7 Series Training Text for Service Engineers
Edition 6.0 Chapter 11. Absolute Encoder Recovery Procedure [4/4]
Absolute Encoders
Incremental encoders
Let’s imagine that the resolution of the X-axis motor is 6000 pls., i.e. for every one revolution of the
motor, 6000 pulse are emitted. After each resolution is complete, that information is stored in the
amp’s memory. For example, the motor moves from the zero pulse position to the 25,000 pulse
position. This is equivalent to 4 full revolutions and another 1000 pulses. While the machine power is
on, we always know the motor position, because we measured the zero position upon booting up the
machine. Once the machine power is turned off, however, we lose that initial zero position, and when
we turn on the machine power again, the only thing the machine can remember is the 1000 pulses as
it is the number of pulses from the home pulse.
Absolute Encoders
Absolute encoders are similar in the method they use to count pulses, however, even after rebooting,
they still remember their absolute position. As each rotation of the motor is made, this information is
stored in the amp’s memory, e.g. 1 rev., or two revs.
In the above case, the motor travels 4 revolutions, and a further 1000 pulses. An initialization file,
stored inside the amp contains motor resolution info.(this is programmed at the factory or by
Yasukawa). After rebooting the motor, the amp reinitializes, reading the initialization file to multiply the
number contained in that file with the number of revolutions stored in the amp’s memory. The other
1000 pulses can be ascertained using the same method as the incremental encoders, i.e. reading the
motor’s current position.
Motors utilizing absolute encoders themselves are not any cheaper than those with incremental
encoders, however, their use eliminates the need for zero set sensor, dog, wire, pcb etc., thus lowering
costs.
Fuji Machine Mfg. Co., Ltd. (Okazaki)
SMT Equipment Quality Assurance Dept.
CS Section
11-4
Chapter 12
Electrical System