Harmonic Drive FHA Series, Руководство пользователя

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Chapter 1 Overview of the FHA-C series
Po s ition difference
Commanded s topping po s ition
Actual s topping
po s ition
S tart po s ition
1-7 One-way positioning accuracy
The one-way positioning accuracy means the maximum
positional difference between a commanded theoretical
position and its actual angular position for serial positioning
in one revolution when approached from the same
direction.(refer to JIS B-6201-1987)
The one-way positioning accuracy of FHA-C actuators
is almost equal to the angular positioning accuracy of the
Harmonic
®
drive gearing, because the effect on the
positioning error of the built-in motor is reducted to its
1/50 or 1/100 or1/160 by the gearing.
The uni-directional positioning accuracy is shown in the table below:
Model FHA-17C FHA-25C FHA-32C FHA-40C
Item 1:50 1:100 1:160 1:50 1:100 1:160 1:50 1:100 1:160 1:50 1:100 1:160
Uni-directional arc second
60 40 40 40 30 30 40 30 30 40 30 30
positioning accuracy
1-8 Encoder resolution
The motors of FHA-C actuators are equipped with an incremental encoder of 2500 resolutions or an absolute encoder of 1892 resolutions.
Because the motor rotation is reduced to 1/50 or 1/100 or 1/160 by the Harmonic drive® component, the resolution of the output flange is
50 or 100 or 160 times the encoder revolution. Additionally, the incremental encoder signal is used in signal is used in quadrature.
The following high resolutions are obtained:
Encoder Incremental Absolute
Encoder resolution 2,500 (10,000: quadruplicated) 8,192
Reduction Ratio 1:50 1:100 1:160 1:50 1:100 1:160
Resolution of output flange Pulse/rev 500,000 1,000,000 1,600,000 409,600 819,200 1,310,720
Resolvable angle per pulse arc sec 2.6 1.3 0.8 3.2 1.6 1.0
(All values are approximate.)
1-9 Torsional Stiffness of Actuators
1-9-1 Moment stiffness
The moment stiffness refers to the torsional stiffness when
a moment load is applied to the output flange of the actuator
(shown in the figure to the right).
For example, when a load is applied to the end of an arm
attached on the output flange, the face of the output flange tilts
in proportion to the moment load. The moment stiffness is
expressed as the torsional moment/angle.
DO NOT APPLY TORQUE, LOAD OR THRUST TO THE SLEEVE DIRECTLY.
Since the sleeve is adhered to the output flange, the adhered sleeve may be detached
from the output flange by the abnormal torque or load.
Model FHA-17C FHA-25C FHA-32C FHA-40C
Item
N
•
m/rad 220 x 10
3
490 x 10
3
790 x 10
3
1400 x 10
3
Moment Stiffness Kgf
•
m/rad 22 x 10
3
50 x 10
3
80 x 10
3
140 x 10
3
Kgf
•
m/arc-min 6.5 15 23 42