Delta DVP-20PM

9 Electronic Cam
9.4.2.6 Applicatio
n of a Flying Shear–Checking the Position of a Cutter
In flying shear application, it is important to check if the cutter is back in designated position when
moving back. If the cutter is not at designated position, it should remain current speed until limit switch
is met, otherwise the mechanical system might be damaged during the moving back process of cutter.
M1757 can be applied to remain current speed of Slave and continue operation until the limit. Users
can compare the designated position with Master position in current cycle to decide if M1757 needs to
be enabled. Master position in current cycle can be obtained by subtracting “Master position captured
at the end of cycle” from accumulated Master position (DD1862). Master position captured at end of
cycle can be read out by using DFROM instruction (D0=K10005, Capture mode).
 Example
【Function】
Check whether the cutter position is correct and automatically determine the execution of M1757.
【Steps】
1. Run the program and read the electronic cam status in capture mode by DFROM instruction.
Read the data in CR#10005 (Capture mode) of special module K100 to D300~D308 at the end
of cycle.
2. Subtract the captured Master position (D306) from the number of accumulated MPG input
pulses (D1862), and users can obtain the actual Master position in current cycle (D350).
3. Compare the actual Master position (D350) with the target position (D1842). If the actual Master
position is bigger than the target position and the limit switch has not been triggered, execute
M1757 then stop the CAM operation.
【Program】
M1000
DMOV K10005 D0
DSUB
D1862
D306
DTO K100 D0 D300 K5
M1802
D350
DLD=
D1846 H2000
DLD> D350
D1842
SET M1757
M1792
X1
9.5 Multi-axis Cam
Single-axis electronic cam can be executed in cyclic operation and noncyclic operation. Unlike
single-axis electronic cam, multi-axis cam can only be executed in cyclic operation. For multi-axis cam,
only one set of electronic cam charts can be applied, i.e. cam chart 0~cam chart 2 correspond to the
X-axis, the Y-axis, and the Z-axis.
DVP-20PM Application Manual
9-47