B–64113EN–1/01
9. SPINDLE SPEED FUNCTION
612
As shown in the figure below a gear ratio can be inserted between the
spindle and spindle motor, and between the spindle and position coder.
Spindle control
Spindle amplifier
Spindle motor
Spindle
Gear ratio n:m
4
Error
counter
Gear ratio q:p
1024 p/rev
Position
coder
(The 512 pulses/rev position coder is incorporated into some
spindle motors. When the serial spindle is used, the system
carries out conversion from 512 pulses/rev to 1024 pulses/rev.)
Up to three gear stages (1st spindle of M series) or four gear stages (1st
spindle of T series) can be provided between the spindle and the spindle
motor. The gear ratio is arbitrary. Up to two gear stages (2nd spindle) can
be provided between the spindle and the spindle motor. The distance of
spindle rotation per revolution of spindle motor is different, based on the
gear ratio. The speed command to the spindle motor will be adjusted. See
(2), below, for additional information regarding a spindle motor incorpo-
rating a position coder.
The position coder is used to detect the position of the spindle.
The gear ratio for the spindle and position coder is specified in the parame-
ter sets No. 5221 to No. 5223 and No. 5231 to No. 5233, or parameter set
PG1 and PG2 No. 3706 #0, #1, parameter P21, P22 (No. 3707 #0, #1) for
2nd spindlee. Which parameter is set for use is specified by parameter
VGR No. 5200 #1.
This is used if the gear ratio for the spindle motor and position coder
(built-in or separate) is not 1:1, 1:2, 1:4, or 1:8, set VGR to 1 and set the
gear ratio using parameter No. 5221 to 5224.
When position coder is mounted on a spindle, the gear ratio for the spindle
motor and position coder cannot be changed by shifting the spindle motor
and spindle gears. Parameters No. 5221 to 5224 must all specify the same
value for the teeth of the individual spindle gears. Parameters No. 5231
to 5234 must all specify the same value for the teeth of individual position
coder gears.
9.10.2
Connection Among
Spindle, Spindle Motor,
and Position Coder
(1) Gear between spindle
and spindle motor
(2) Gear between spindle
and position coder
S Arbitrary gear ratio
(VGR=1)