Mitsubishi MELDAS HS Series Specifications And Instruction Manual page 126

(1) Horizontal axis load torque
When operations ① to ⑧ are for a horizontal axis, calculate so that the following torques are
required in each period.
Period Load torque calculation method
(Amount of acceleration torque) +
①
(Kinetic friction torque)
②
(Kinetic friction torque)
(Amount of deceleration torque) +
③
(Kinetic friction torque)
④
(Static friction torque)
− (Amount of acceleration torque) −
⑤
(Kinetic friction torque)
− (Kinetic friction torque)
⑥
− (Amount of deceleration torque) −
⑦
(Kinetic friction torque)
− (Static friction torque)
⑧
(2) Unbalance axis load torque
When operations ① to ⑧ are for an unbalance axis, calculate so that the following torques are
required in each period. Note that the forward speed shall be an upward movement.
Period Load torque calculation method
(Amount of acceleration torque) +
①
(Kinetic friction torque) + (Unbalance
torque)
(Kinetic friction torque) + (Unbalance
②
torque)
(Amount of deceleration torque) +
③
(Kinetic friction torque) + (Unbalance
torque)
(Static friction torque) + (Unbalance
④
torque)
− (Amount of acceleration torque) −
⑤
(Kinetic friction torque) + (Unbalance
torque)
− (Kinetic friction torque) +
⑥
(Unbalance torque)
− (Amount of deceleration torque) −
⑦
(Kinetic friction torque) + (Unbalance
torque)
− (Static friction torque) +
⑧
(Unbalance torque)
During a stop, the static friction torque may constantly be applied. The static
friction torque and unbalance torque may particularly become larger during an
POINT
unbalance upward stop, and the torque during a stop may become extremely
large. Therefore, caution is advised.
Chapter 11 Selection
Table 11-6 Load torques of horizontal axes
Normally the acceleration/deceleration time constant is
calculated so this torque is 80% of the maximum torque of
the motor.
The signs for the amount of acceleration torque and amount
of deceleration torque are reversed when the absolute value
is the same value.
Calculate so that the static friction torque is always required
during a stop.
The signs are reversed with period ① when the kinetic
friction does not change according to movement direction.
The signs are reversed with period ② when the kinetic
friction does not change according to movement direction.
The signs are reversed with period ③ when the kinetic
friction does not change according to movement direction.
Calculate so that the static friction torque is always required
during a stop.
Table 11-7 Load torques of unbalance axes
Normally the acceleration/deceleration time constant is
calculated so this torque is 80% of the maximum torque of
the motor.
The signs for the amount of acceleration torque and amount
of deceleration torque are reversed when the absolute value
is the same value.
The holding torque during a stop becomes fairly large.
(Upward stop)
The generated torque may be in the reverse of the movement
direction, depending on the size of the unbalance torque.
The holding torque becomes smaller than the upward stop.
(Downward stop)
11–8
Explanation
Explanation