Yamaha YK-X Series, User Manual

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4-4
CHAPTER 4 Adjustment
3-2 Machine reference
The YK-XG series position detectors are resolvers that have four positions where
absolute reset can be performed per motor revolution. If the sensor method is
used for the absolute reset, the origin position will be set at the positions where
absolute reset can be performed soon after the origin sensor reacts to the dog (the
origin signal is detected). The machine reference means the position relationship
of the position where the robot detects the origin signal to the position where the
absolute reset can be performed soon after detection (see Fig. 4-1). The machine
reference is expressed with the ratio of interval A to interval B shown in Fig. 4-1.
Interval A is the minimum distance between the positions where absolute reset
can be performed and interval B is the distance between the position where the
origin signal is detected and the position where absolute reset can be performed
soon after the origin signal detection. The machine reference value (unit: %) is
displayed on the optional MPB screen.
Machine reference value = B/A
×
100(%)
! CAUTION
The machine reference must be adjusted within a specified range to keep the
repeatability precision of the absolute reset position (The machine reference is
factory-adjusted prior to shipping). If the origin position is changed, the ma-
chine reference must be readjusted. For information on how to adjust the ma-
chine reference, refer to "3-4 Changing the origin position and adjusting the
machine reference" in Chapter 4. When the temperature of the robot joint sec-
tions is high immediately after the robot has been operated, the machine refer-
ence value might be outside the specified range (40 to 60%). When checking or
adjusting the machine reference value, always make sure that the temperature
of the robot joint sections has returned to room temperature.
Recommended machine reference value: 40 to 60%
Machine reference
Origin signal detection
Origin signal
Resolver
Positions where absolute reset
can be performed
One motor revolution
B A
ON
OFF
Machine reference display on MPB screen
MANUAL >RST. ABS 50% [MG] [S0H0J]
Machine reference (%)
M1= 50
M4= 66
M2= 56 M3= 52
M1 M2 M3 M4 M5
R-axis X-axis Y-axis Z-axis
MPB
Fig. 4-1