Harmonic Drive RSF Series, Руководство пользователя

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Chapter 2 Selection of the RSF supermini Series
RSF-super_V1_02
- 16 -
◆
Horizontal linear motion
The following formula calculates the torque for horizontal linear motion of mass [W] fed by the screw of
pitch [P].
π ×
× × μ × =
2
P
W 8 . 9 T
T: torque (N
･
m)
μ : coefficient of friction
W: mass (kg)
P: screw pitch (m)
◆
Vertical linear motion
The following formula calculates the torque for vertical linear
motion of mass [W] fed by the screw of pitch [P].
π ×
× × =
2
P
W 8 . 9 T
2-4-4 Acceleration time and deceleration time
Calculate acceleration and deceleration times for the selected actuator.
Acceleration:
( )
L M
L A a
T T
N
60
2
J J t
−
×
π ×
× + =
(1)
Deceleration:
( )
L F M
L A d
T T 2 T
N
60
2
J J t
− × +
×
π ×
× + =
(2)
T
a
: acceleration time (sec)
T
d
: deceleration time (sec)
J
A
: actuator inertia (kg
･
m
2
)
J
L
: load moment of inertia (kg ･ m
2
)
N: actuator speed (r/min)
T
M
: maximum torque of actuator (N
･
m)
T
L
: load torque (N ･ m)
note that the polarity of the load torque is plus (+) for counter direction of revolution , and
minus (-) for same direction.
The friction torque of the actuator T
F
(N
･
m) can also be obtained from the following formula:
T
F
=K
T
×
I
M
-T
M
(3)
K
T
: Torque constant [N ･ m/A]
I
M
: Maximum current [A]
Mass: W
Pitch: P
Friction: μ
Pitch: P
Mass: W
ta td
N
Time
Speed