Siemens SINUMERIK 880 Programming Manual page 237

11 Programming of Cycles
11.10 NC-specific functions
@71c <Value 1> <Value 2> <Value 3> <Value 4>
This function is relevant only to the electronic gearbox (ELG) and the "Synchronous
spindle" function. The leading axis is defined as a spindle. The following axis is defined
with <Value 1> and the leading axis (spindle) with <Value 2>.The required transmission
ratio K between the leading and following axis is determined by <Value3> and <Value
ü
4>. K is obtained as the quotient from <Value 3> (numerator) and <Value 4>
ü
(denominator).
Example:
@71c K5 K1 K2 K31
Main group 7/subgroup 2: Measurement functions
@720 <Var> <Value>
This command is used in measuring cycles.
With the measurement function, the actual values of the traversing axes are determined at
the time of an input signal from the probe. The actual values are recorded direct from the
measurement circuits of the control when the switching edge of the probe signal is
recognized. The actual values are stored in ascending sequence of axis number as from
parameter <Var> and are referred to machine zero. The control subsequently generates
a "Delete distance-to-go", i.e. the distances to go (differences between setpoints and
actual values) are deleted for all axes. Set value 0 is specified as jump function by the
control. The deceleration paths of the axes are still traversed, i.e. the following errors are
reduced. This means that the next traverse blocks must be programmed in absolute
dimensions (G90).
The sensor position must not lie within the exact stop range of the programmed end point.
The actual values recorded at the time of measuring the traversing axes are stored in
ascending sequence of axis number starting at the parameter defined in <Var>.
The number of the measurement input (1 or 2) is specified with <Value>.
The traversing paths of the axes (setpoint positions) are programmed via DIN code or the
command @ 440 in the same NC block. The setpoint positions of the axes are referred to
workpiece 0. The @720 measuring command can only be used in conjunction with G01
(linear interpolation). The @720 command cannot be programmed for software axes.
Measurements cannot be carried out with both sensors simultaneously in different
channels. The second measuring block is therefore not initiated until the first measuring
block has been completed.
Example:
@720 R93 K1
@440 K1 R70
@714
Note:
With rotary axes, the result is stored in altogether two R parameters from R parameter
<Var> (Rn) onwards, depending on an NC machine data bit.
The following parameters are loaded:
Rn = Position within one revolution
Rn+1 = Number of revolutions
11–50
The transmission ratio between the following axis
(axis 5) and the leading axis (spindle 1) is 2/31.
The actual value of the 1st axis is measured and
loaded in R93.
© Siemens AG 1991 All Rights Reserved
01.93
6ZB5 410-0HD02
SINUMERIK 880, (PG)