Harmonic Drive RSF supermini Series User manual

AC Servo Actuator
RSF supermini Series Manual
(With RSF-3Cand RSF-5B)
ISO14001
ISO9001

Introduction
Thank you very much for your purchasing our RSF supermini series servo actuator.
Be sure to use sufficient safety measures when installing and operating the equipment so as to
prevent an accident resulting in a serious physical injury damaged by a malfunction or improper
operation.
Product specifications are subject to change without notice for improvement purposes.
Keep this manual in a convenient location and refer to it whenever necessary in operating or
maintaining the units.
The end user of the actuator should have a copy of this manual.

1
SAFETY GUIDE
To use the servo system safely, be sure to read SAFETY GUIDE and other parts of this document
carefully and fully understand the information provided herein before using the driver.
NOTATION
Important safety information you must note is provided herein. Be sure to observe these instructions.
Indicates a potentially hazardous situation, which, if not avoided, could result
in death or serious personal injury.
Indicates a potentially hazardous situation, which, if not avoided, may result in
minor or moderate personal injury and/or damage to the equipment.
LIMITATION OF APPLICATIONS
The equipment listed in this document may not be used for the applications listed below:
・
Space equipment
・Aircraft, aeronautic equipment
・Nuclear equipment
・Household apparatus
・Vacuum equipment
・Automobile, automotive parts
・Amusement equipment
・Machine or devices acting directly on the human body
・Instruments or devices to transport or carry people
・Apparatus or devices used in special environments
・
Instruments or devices to prevent explosion
If the above list includes your intending application for our products, please consult us.
If this product is utilized in any facility in which human life is
at stake or that may incur material losses, install safety
devices so that accidents will not occur even when the
output control is disabled due to damage.
WARNING
CAUTION
CAUTION

SAFETY GUIDE
2
SAFETY NOTE
Precautions when using a direct drive motor
NOTICES ON DESIGN
BE SURE TO READ THE MANUAL FOR DESIGNING.
Always use under followings conditions:
The motor is designed to be used for indoor.
- Ambient temperature: 0°C to 40°C
- Ambient humidity: 20% to 80%RH (Non-condensation)
- Vibration: 49 m/s2or less
- No contamination by water, oil
- No metal powder, dust, oil mist, corrosive gas, or explosive gases
Follow exactly the instructions to install the actuator in the
equipment.
- Ensure exact alignment of motor shaft center and corresponding center in
the application.
- Failure to observe this caution may lead to vibration, resulting in damage of
output shaft.
OPERATIONAL PRECAUTIONS
BE SURE TO READ THE MANUAL BEFORE OPERATING THE PRODUCT.
Never connect cables directly to a power supply socket.
- Direct drive motor cannot be operated unless it is connected to dedicated
driver.
- Never connect it to commercial power supply directly. Direct drive motor
may be damaged and causes fire.
Do not apply shocks to actuator.
- Do not apply shocks because direct drive motor is directly connected to
high precision encoder.
- If the encoder is damaged, it may cause uncontrollable operation.
Avoid handling of motor by cables.
- Failure to observe this caution may damage the wiring, causing
uncontrollable or faulty operation of direct drive motor.
Keep limited torques of the actuator.
- Keep limited torques of the actuator.
- Be aware that, if arms directly attached to the output shaft are hit, the
output shaft may become non-controllable.
CAUTION
WARNING
CAUTION

SAFETY GUIDE
3
Precautions when using a driver
NOTICES ON DESIGN
BE SURE TO READ THE MANUAL FOR DESIGNING.
Always use drivers under followings conditions:
The driver generates heat. Take extra caution for radiation and use it under the
following conditions.
- Mount in a vertical position keeping sufficient distance.
- 0 to 50℃, 95% RH or below (Non condensation)
- No vibration or shocks
- No metal powder, dust, oil mist, corrosive gas, or explosive gases
Use sufficient noise suppressing means and safe grounding.
Any noise generated on a signal wire will cause vibration or improper motion.
Be sure to observe the following conditions.
- Keep signal and power leads separated.
- Keep leads as short as possible.
- Ground actuator and driver at one single point, minimum ground resistance
class: D (less than 100 ohms)
- Do not use a power line filter in the motor circuit.
Pay attention to negative torque by inverse load.
- Inverse load may cause damages of direct drive motor.
Please consult our sales office, if you intend to apply products for inverse
load.
Use a fast-response type ground-fault detector designed for
PWM inverters.
When using a fast-response type ground-fault detector, use one that is
designed for PWM inverters. Do not use a time-delay-type ground-fault
detector.
If this product is utilized in any facility in which human life is
at stake or that may incur material losses, install safety
devices so that accidents will not occur even when the
output control is disabled due to damage.
CAUTION

SAFETY GUIDE
4
OPERATIONAL PRECAUTIONS
BE SURE TO READ THE MANUAL BEFORE OPERATING THE PRODUCT.
Never change wiring while power is active.
Make sure to turn OFF the power before detaching wires, or disconnecting or
connecting the connectors. Failure to observe this caution may result in
electric shock or uncontrollable operation.
Do not touch terminals immediately after turning OFF power.
- Even after the power supply is turned OFF, electric charge remains in the
driver. To prevent electric shock, perform an inspection upon confirming
that the charge voltage monitor LED on the panel is turned OFF after the
power is turned off.
- Make installation of products not easy to touch their inner electric
components.
Do not make a voltage resistance test.
- Do not perform a megger test or voltage resistance test. Failure to observe
this caution may result in damage to the control circuit of the driver.
Please consult our sales office, if you intent to make a voltage resistance
test.
Do not operate control units by means of power ON/OFF
switching.
- Frequent power ON/OFF may result in deterioration of internal circuit
elements.
- Start/stop operation should be performed via input signals.
DISPOSAL
DISPOSAL OF AN ACTUATOR AND/OR A DRIVER
All products or parts have to be disposed of as industrial
waste.
Dispose of these items as industrial waste.
WARNING
CAUTION
CAUTION

5
Contents
SAFETY GUIDE.....................................................................................................1
NOTATION....................................................................................................1
LIMITATION OF APPLICATIONS..................................................................1
SAFETY NOTE.............................................................................................2
Contents.................................................................................................................5
Chapter 1 Overview of the RSF supermini Series
1-1 Overview of RSF supermini Series........................................................... 1-1
1-2 Major characteristics................................................................................. 1-1
1-3 Ordering information................................................................................. 1-2
Actuator Model.......................................................................................... 1-2
1-4 Combinations with drivers.......................................................................... 1-2
1-5 Specifications of RSF supermini actuators ............................................... 1-4
1-6 External dimensions of actuators.............................................................. 1-6
1-7 One-way positioning accuracy.................................................................. 1-8
1-8 Torsional stiffness ..................................................................................... 1-9
1-9 Detector resolution.................................................................................. 1-10
1-10 Mechanical accuracy ...............................................................................1-11
1-11 Allowable load......................................................................................... 1-12
Allowable radial load and allowable thrust load ...................................... 1-12
Radial load when the operating point is different.................................... 1-13
1-12 Rotary direction....................................................................................... 1-14
1-13 Impact resistance.................................................................................... 1-14
1-14 Vibration resistance ................................................................................ 1-14
1-15 Operable range....................................................................................... 1-15
1-16 Cable specifications................................................................................ 1-17
Chapter 2 Selection of the RSF supermini Series
2-1 Allowable load moment of inertia.............................................................. 2-1
2-2 Variable load inertia .................................................................................. 2-1
2-3 Verifying loads........................................................................................... 2-1
2-4 Examining operating status....................................................................... 2-2
Examining actuator rotation speed ........................................................... 2-2
Calculating and examining load inertia moment ....................................... 2-2
Calculating load torque............................................................................. 2-2
Acceleration time and deceleration time................................................... 2-3

Contents
6
Examining duty......................................................................................... 2-4
Examining effective torque and average rotational speed........................ 2-8
Permissible overloaded time..................................................................... 2-9
Chapter 3 Installing the actuator
3-1 Receiving inspection................................................................................. 3-1
3-2 Notice on handling.................................................................................... 3-2
3-3 Location and installation ........................................................................... 3-3
Environment of location ............................................................................ 3-3
Considerations into External Noise........................................................... 3-3
Installation................................................................................................. 3-4
Chapter 4 Motor shaft retention brake(RSF-5B)
4-1 Motor shaft retention brake specifications................................................. 4-1
4-2 Controlling the brake power supply........................................................... 4-2
Using a relay cable (Recommended method)........................................... 4-2
Not using a relay cable............................................................................. 4-2
Chapter 5 Options
5-1 Relay cables ............................................................................................. 5-1
5-2 Relay cable wire bound specifications...................................................... 5-2
5-3 Connectors ............................................................................................... 5-5
Appendix
A-1 Conversion of unit.....................................................................................A-1
A-2 Moment of inertia......................................................................................A-3
1. Calculation formulas for mass and moment of inertia...........................A-3
2. Moment of inertia of circular cylinder....................................................A-5

1-0
Chapter 1
Overview of the RSF supermini Series
1-1 Overview of RSF supermini Series ········································1-1
1-2 Major characteristics ··························································1-1
1-3 Ordering information ··························································1-2
1-4 Combinations with drivers····················································1-2
1-5 Specifications of RSF supermini actuators ······························1-4
1-6 External dimensions of actuators ··········································1-6
1-7 One-way positioning accuracy··············································1-8
1-8 Torsional stiffness······························································1-9
1-9 Detector resolution··························································· 1-10
1-10 Mechanical accuracy·························································1-11
1-11 Allowable load ································································ 1-12
1-12 Rotary direction······························································· 1-14
1-13 Impact resistance ···························································· 1-14
1-14 Vibration resistance·························································· 1-14
1-15 Operable range······························································· 1-15
1-16 Cable specifications ························································· 1-17

1-1 Overview of RSF supermini Series
1-1
1
2
3
4
5
6
Overview of the RSF supermini series
1-1
Overview of RSF supermini Series
The ultra-compact RSF supermini servo actuators utilize zero backlash Harmonic Drive® precision
gears, a brushless servo motor and an incremental encoder to deliver precision motion control.
Actuators with an electromagnetic brake are also included in the lineup. They can meet fail-safe
requirements of equipment to prevent accidents upon power supply failure.
The RSF supermini series can contribute to downsizing of driving of robot joints, semiconductor/LCD
panel manufacturing equipment, machine tools, and other FA equipment. By utilizing its small and
high-torque characteristics, it can also be used for small equipment and for research.
.
1-2 Major characteristics
Small, lightweight, and high-torque
The RSF supermini actuators are the union of Harmonic Drive® gearing with a super-flat AC
servomotor. The ultra-compact size allows integration to smaller machines. RSF supermini
series actuator outputs have a much higher torque per volume than direct drive motors.
Standard lineup of actuators with a brake (only RSF-5B)
The standard lineup of AC servo actuators includes the deenergisation operation type actuators
with an electromagnetic brake for the first time for this size of actuators.
Fail-safe requirements of equipment can be met to prevent accidents upon power failure without
providing any external brake or changing the equipment structure to install a brake.
Advanced positioning accuracy
Integrated Harmonic Drive® gear for zero backlash and advanced positioning accuracy.
Stable controllability
By high reduction ratio of speed reducer, stable controllability is gained against change in load
inertia moment.
Wide operation range
The newly developed servo motor features a maximum rotational speed of the motor itself to
10,000rpm, thereby expanding the operational range of the actuator.

1-3 Ordering information
1-2
1
2
3
4
5
6
Overview of the RSF supermini series
1-3 Ordering information
Model codes for the RSF supermini series actuators are as follows:
Actuator Model
1-4 Combinations with drives
The The RSF supermini series actuators can be used in combination with the DCJ, DDP,
and HA-680 drives.
•Drives can perform position control, speed control, and torque control.
•For details of the drivers, refer to the “driver manual or data sheet”.
•Extension cables are required for connection between the actuator and the drive.
RSF-5 B-50-E 050-C-SP
Model: AC servo actuator
Series: RSF series
Frame size: 3 or 5
Design version
Encoder pulses on motor shaft
020: 200p/rev (size 3)
050: 500p/rev (size 5)
Reduction ratio of HarmonicDrive®Speed Reducer
30:1
50:1
100: 1
Option
C: (Standard product) With connector
BC: (size 5 only): With brake or connector
Encoder specifications
E: incremental encoder
Special specification
No symbol: Standard product
SP: Special product

1-4 Combinations with drives
1-3
1
2
3
4
5
6
Overview of the RSF supermini series

1-5 Specifications of RSF supermini actuators
1-4
1
2
3
4
5
6
Overview of the RSF supermini series
1-5
Specifications of RSF supermini actuators
Specifications of actuators are as follows:
Time rating:
Continuous
Service temperature:
0~40°C
Excitation method:
Permanent magnet type
Storage temperature:
-20~+60°C
Insulation class: B
Humidity
(Operating/Storage)
20~80%RH (no condensation)
Withstanding
voltage:
AC500V/min
Vibration
resistance:
Note7
49m/s2(10-400Hz)
Insulation
resistance:
DC500V 100MΩor more
Shock
resistance:
Note7
300m/s2
Structure:
Totally enclosed self
cooling
Lubricant: Grease (Harmonic Grease®)
Size
Item
RSF-3C
RSF-5B
30
50
100
30
50
100
Power supply
voltage(diver)
V DC24±10% DC24±10%
Allowable
continuous
current
A
rms
0.65 0.66 0.56 1.11 0.92 0.76
Allowable
continuous torque
Nm 0.03 0.07 0.11 0.18 0.29 0.44
(during operation
at allowable
continuous
rotation speed)
kgfcm 0.31 0.68 1.08 1.83 2.95 4.48
Allowable
continuous
rotation speed
(output shaft)
rpm 150 90 45 150 90 45
Allowable
continuous stall
torque
Nm
0.04
0.08
0.12
0.28
0.44
0.65
kgfcm 0.41 0.82 1.22 2.85 4.48 6.62
Instantaneous
maximum current
Arms 1.5 1.4 1.1 2.3 2.2 1.7
Max. torque
Nm
0.13
0.21
0.30
0.5
0.9
1.4
kgfcm
1.27
2.05
2.94
5.1
9.17
14.3
Max. speed
rpm
333
200
100
333
200
100
Torque constant
Nm/Arms
0.11
0.18
0.40
0.3
0.54
1.1
kgfcm/A
1.12
1.84
4.08
3.06
5.51
11.22
EMF constant
V/(rpm)
0.015
0.025
0.05
0.04
0.07
0.13
Phase resistance
(at 20°C)
Ω1.34 0.82
Phase inductance
mH
0.18
0.27
Moment
of inertia
Note 3
GD
2
/4 kgm2
0.11×10-4
0.29×10-4
1.17×10-4
0.66×10-4
1.83×10-4
7.31×10-4
（
0.11×10-3
） （
0.31×10-3
） （
1.23×10-3
）
J kgfcms2
1.07×10-4
2.98×10-4
11.90×10-4
0.67×10-3
1.87×10-3
7.45×10-3
（
1.13×10-3
） （
3.15×10-3）
（
12.6×10-3
）
Gear ratio
30
50
100
30
50
100
Allowable radial
load
(output shaft
central value)
N
36
90
kgf
3.6
9.1
Allowable thrust
load
N
130
270
kgf
13.2
27.5

1-5 Specifications of RSF supermini actuators
1-5
1
2
3
4
5
6
Overview of the RSF supermini series
Size
Item
RSF-3C
RSF-5B
30
50
100
30
50
100
Encoder pulses
(motor shaft) Pulse/ 200 500
Encoder
resolution
(Output shaft:
when multiplied
by 4)
Note 4
Pulse/
Rotation 24,000 40,000 80,000 60,000 100,000 200,000
Motor
shaft
brake
Input
power
supply
voltage
V
-
DC24±10%
Retention
torque
Nm
-
0.18
0.29
0.44
kgfcm
-
1.83 2.95 4.48
Mass
Note 5
Without
brake
g 31 (except clamp filter) 66 (except clamp filter)
With
brake
g - 86 (except clamp filter)
Recommended
drive
HA-680-4B-24 HA-680-4B-24
DCJ-055-09, DDP-090-09
Note 1: The table shows typical output values of actuators.
Note 2: the values in the table above are obtained when it is combined with the combined driver
(HA-680-4B-24).
Note 3: Moment of inertia is the total value of the motor shaft and the HarmonicDrive®gear moment of inertia
values converted to the output side. The values in parentheses are for model with a brake.
Note 4: The encoder resolution is (motor shaft encoder resolution when multiplied by 4) x (gear ratio).
Note 5: The mass of clamp filter is 6g for each.
Note 6: Refer to "1-13 Vibration resistance" or "1-14 Shock resistance" on page 12 for the test conditions.

1-6 External dimensions of actuators
1-6
1
2
3
4
5
6
Overview of the RSF supermini series
1-6 External dimensions of actuators
The external drawings are shown as follows:
RSF-3C-XXX-E020-C
Note) For detailed external dimensions, check the delivery specification drawing issued by us.
Tolerances may vary due to product manufacturing method (foundry piece, machine-finished good).
If necessary, please contact us for the tolerance when it is not indicated in the dimensions.
2-plane cut
Line locating Motor lead wire
range of Encoder cable wire
Motor lead wire
( Finished outside diameter :
φ5Max)
Encoder lead wire
( Finished outside diameter :
φ3.3Max)
Clamp filter(2) ZCAT1518-0730(TDK)

1-6 External dimensions of actuators
1-7
1
2
3
4
5
6
Overview of the RSF supermini series
RSF-5B-XXX-E050-C
RSF-5B-XXX-E050-BC(with brake)
Note) For detailed external dimensions, check the delivery specification drawing issued by us.
Tolerances may vary due to product manufacturing method (foundry piece, machine-finished good).
If necessary, please contact us for the tolerance when it is not indicated in the dimensions.
3-M2x3 evenly spaced
2-φ2.3 evenly spaced
FG line
Motor lead wire
( Finished outside diameter :
φ6Max)
( Finished outside diameter :
φ3.3Max)
Clamp filter(2) ZCAT1518-0730(TDK)
Encoder lead wire
3-M2x3 evenly spaced
Motor and Brake lead wire
Motor lead wire
FG line
2-φ2.3 evenly spaced
( Finished outside diameter :
φ6Max)
( Finished outside diameter :
φ3.3Max)
Encoder lead wire
Clamp filter(2) ZCAT1518-0730(TDK)
Brake lead wire

1-7 One-way positioning accuracy
1-8
1
2
3
4
5
6
Overview of the RSF supermini series
1-7 One-way positioning accuracy
The following table shows the “one-way positioning accuracy."
The The “one-way positional accuracy” represents the maximum difference in a single revolution
among differences between an angle actually rotated from the datum position and one that is
supposed to turn in each position by repeating sequential positioning in a preset rotational direction.
The RSF supermini series contains a HarmonicDrive® speed reducer for precision control and
positioning errors of the motor shaft are therefore compressed to 30:1, 50:1 or 100:1 by speed
reduction. In reality, angular transmission errors of the speed reducer determine the one-way
positional accuracy. The measured values of angular transmission errors of the speed reducer are
therefore shown as the one-way positional accuracy of the RSF supermini series.
The accuracy for each gear ratio is shown below.
Model RSF-3C RSF-5B
Gear ratio
Item 30 50 100 30 50 100
One-
way positioning
accuracy
arc min 10 4 3 3
rad
2.9×10
-3
1.20×10
-3
0.87×10
-3
0.87×10
-3
Reference
(Accuracy display and measurement method
according to JIS B 6201: 1987)
One-way positioning of rotation shaft motion
First, perform positioning at any one position in a fixed
direction. This position is the reference position. Next,
perform positioning in succession in the same
direction, and measure the difference between the
angle actually rotated from the reference position and
the desired angle at each position. The maximum
difference in one rotation among these values is taken
as the measurement value. Measurement of
equipment with the continuous positioning function for
rotational motion shall be done once per 30 degrees
or 12 positions throughout the entire rotation range as
a rule.

1-8 Torsional stiffness
1-9
1
2
3
4
5
6
Overview of the RSF supermini series
1-8 Torsional stiffness
When a torque is applied to the output flange of the actuator with the motor locked, the resulting
torsional wind up is near proportional to the torque.
The upper right figure shows the torsional stiffness
characteristics of the output flange applying torque starting
from zero to plus side [+T0]and minus side [–T0]. This
trajectory is called torque-torsion characteristics which
typically follows a loop 0→A→B→A’→B’→A as illustrated. The
torsional stiffness of the RSF supermini actuator is expressed
by the slope of the curve that is a spring rate (wind-up)
(unit:N･m/rad).
The torsional stiffness may be evaluated by dividing
torque-torsion characteristics curve into three major regions.
The spring rate of each region is expressed K1, K2, and K3
respectively.
K1: spring rate for torque region 0-T1
K2: spring rate for torque region T1-T2
K3: spring rate for torque region over T2
The wind-up for each region is expressed as follows:
wind-up for torque region 0-T1:
wind-up for torque region T1-T2:
wind-up for torque region over T2:
The following table shows average values of T1through T3, K1 through K3, and θ1 through θ2 for
different gear ratios.
Model
RSF-3C
RSF-5B
Gear ratio
Symbol 30 50 100 30 50 100
T1
Nm
0.016
0.016
0.016
0.075
0.075
0.075
kgfm
0.0016
0.0016
0.0016
0.0077
0.0077
0.0077
K1
Nm/rad
27
30
34
90
110
150
kgfm/arc min
0.0008
0.0009
0.0010
0.003
0.003
0.004
θ1
x10-4 rad
5.9
5.3
4.7
8.7
6.9
5
arc min
2.0
1.8
1.6
3
2.4
1.7
T2
Nm
0.05
0.05
0.05
0.22
0.22
0.22
kgfm
0.005
0.005
0.005
0.022
0.022
0.022
K2
Nm/rad
40
47
54
110
140
180
kgf m/arc min
0.0012
0.0014
0.0016
0.003
0.004
0.005
θ2
x10-4 rad
12.5
10.6
9.3
22
18
13
arc min
4.2
3.6
3.1
7.5
6
4.4
K3
Nm/rad
51
57
67
120
170
200
kgfm/arc min
0.0015
0.0017
0.0020
0.004
0.005
0.006
1K
T
=ϕ
2
1
1KTT −
+θ=ϕ
3
2
2
KTT −
+θ=ϕ

1-9 Detector resolution
1-10
1
2
3
4
5
6
Overview of the RSF supermini series
1-9 Detector resolution
An encoder with 200 pulses for RSF-3C, 500 pulses for RSF-5B per rotation is incorporated in the
motor unit of the RSF supermini series actuators, and the motor output is decelerated by 30:1, 50:1, or
100:1 by the Harmonic Drive® speed reducer. Therefore, the resolution per one rotation of the
actuator output shaft is 30, 50, or 100 times of the actual encoder resolution. In addition, the encoder
signal is electrically multiplied by 4.
The following table shows the resolution at the output shaft for different gear ratios.
Model RSF-3C RSF-5B
Gear ratio
Item 30 50 100 30 50 100
Detector resolution
(when multiplied by 4) Pulse/Rotation 24,000 40,000 80,000 60,000 100,000 200,000
Angle per one pulse
Angle second
(arc sec)
54 32.4 16.2 21.6 12.96 6.48