Mitsubishi Electric MELDAS C6 Programming Manual page 268

13. Program Support Functions
Optimum speed control
(1) Optimum corner deceleration
By calculating the angle of the seam between blocks, and carrying out acceleration/
deceleration control in which the corner is passed at the optimum speed, highly accurate edge
machining can be realized.
When the corner is entered, that corners optimum speed (optimum corner speed) is calculated
from the angle with the next block. The machine decelerates to that speed in advance, and
then accelerates back to the command speed after the corner is passed.
Corner deceleration is not carried out when blocks are smoothly connected. In this case, the
criteria for whether the connection is smooth or not can be designated by the machining
parameter "#8020 DCC ANGLE".
When the corner angle is larger than the parameter "DCC ANGLE" for a linear−linear
connection, or for a circle, etc, and the corner is passed at a speed V, the acceleration ∆V
occurs due to the change in the direction of progress.
The corner angle V is controlled so that this ∆V value becomes less than the pre-interpolation
acceleration/ deceleration tolerable value set in the parameters ("#1206 G1bF", "#1207
G1btL").
In this case the speed pattern is as follows.
Y axis
X axis
N01 G01X100.Y1.F500 ;
Combined
speed
Speed
pattern
Time
X axis
Speed
speed
pattern
Time
Y axis
Speed
speed
pattern
Time
θ
V
Speed after the corner is passed
θ
N02 G01X100.Y-1.F500 ;
2
V0 =
V0 V0x + V0y
V0x
V0y
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13.12 High-accuracy control
V Speed before entering the corner
∆V Speed change at the corner
The optimum corner speed is represented
by V0.
V0 is obtained from the pre-interpolation
acceleration/deceleration tolerable value
(∆V') and the corner angle (outside angle)
θ
.
G1bF
∆ V' =
G1btL
To further reduce the corner speed V0
(to further improve the edge accuracy),
the V0 value can be reduced in the
2
machining parameter "#8019
R COMPEN".
V0 × (100 − Ks)
V0' =
Ks: R COMPEN
(Note) In this case, the cycle time
may increase due to the
increase in the time
required for acceleration/
deceleration.
100