RH Series The RH series includes compact and high-torque DC servo actuators with a high rotational accuracy combining a speed reducer HarmonicDrive for precision control and a DC servo motor. A combination with a dedicated servo driver that fully demonstrates the performance of this RH series of implements; compact machines and equipment with a high rotational accuracy. Features High resolution High resolution of maximum 4, pulses/revolution (.9 /pulse) combining a HarmonicDrive. High positional accuracy The HarmonicDrive eliminates backlash caused by gear play, assuring high-accuracy positioning. Compact body and high-output torque High output..69nm (maximum momentary torque achieved) by the smallest model RH-5A with outside dimensions of 2mm in diameter x 89mm. Structure Compact and speed reducer HarmonicDrive for precision control Features a high resolution and positional accuracy. Unmatched light weight and compact properties. High-precision optical encoder Rectangular output signal is dissolved up to x 4. High-performance DC servo motor Output shaft bearing with high stiffness 83
RH Series Models and Symbols Type: DC servo actuator RH series Model Nos.: 5, 8, 11 and 14 Version symbol Output shaft rated rotational speed Shows 6r/min RH 14 D 6 2 E 1 A L Encoder output type O: Open collector type L: Line driver type Encoder power supply A: +5V D: +5 to 12V Encoder resolution 1: 1 pulses / revolution 36: 36 pulses / revolution Option E: Incremental encoder T: Tachometer generator Rated output (W) RH-5, RH-8: x1 RH-11, RH-14: x1 Specification (With an Incremental Encoder) Time rating: Protection: Totally enclosed self-cooled Ambient temperature: to 4 C Ambient humidity: 35 to 8% RH (Do not expose to condensation.) Item Rated Output Rated Voltage Model W V 882 1.5 RH-5A RH-8D RH-11D RH-14D 552 1.7 12 442 1.4 66 8.6 24 36 6.2 61 13.6 24 31 12.3 62 2.3 24 32 18.5 Maximum Momentary Torque Nm kgfcm.39 4..59 6..69 7. 2.7 27 3.5 36 4.9 5 7.8 8 14 14 2 2 Max. Stall Torque Nm kgfcm.24 2.4.39 4..43 4.4 1.5 15 2.3 23 2.5 25 4.4 45 5.4 55 7.8 8 Rated Torque Max. Rotational Speed Rated Rotational Speed Maximum Momentary Current Rated Current Nm kgfcm r/min r/min A A.16 1.6 18 88.83.5.29 3. 11 55.78.5.29 3. 9 44.77.5 1.4 14 1 6 1.6 1. 2. 2 5 3 1.1.8 2.2 22 1 6 2.4 1.3 3.9 4 5 3 2.1 1.3 3.2 33 1 6 5.4 1.8 5.9 6 5 3 4.1 1.8 Torque Constant Nm/A kgfcm/a.69 7.6 1.11 11.3 1.38 14.1 2.1 21.4 4.2 42.9 2.46 25.1 4.91 5.1 2.92 29.8 5.76 58.8 Moment of Inertia *5 GD 2 /4 J kgm 2 kgfcm 2 6.3 1-4.7 16 1-4.16 25 1-4.26 37 1-4.4 15 1-4.15 11 1-4.11 43 1-4.44 21 1-4.21 81 1-4.83 Permissible Radial Load Permissible Thrust Load Reduction Ratio Mass Combined Driver N kgf N kgf kg 5 59 6. 29 3. 8.9 HS-36-1A 1 5 196 2 98 1 1.3 HS-36-1B 5 245 25 196 2 1.5 HS-36-1C 5 392 4 392 4 1.77 HS-36-1D *1: Values shown inn the table above indicate representative values on the output shaft. *2: This is the value when the actuator is combined with the HS-36 driver. *3: If you use the actuator by combining it with the HS-36 driver, chose an encoder that satisfies the line driver specification. *4: The actuator specification shows values when the actuator is installed on the following aluminum radiator plates. RH-5A : 15x15x3 (mm) RH-8D : 15x15x6 (mm) RH-11D : 15x15x6 (mm) RH-14D : 15x15x6 (mm) *5: The inertia moment is the value converted to the output shaft from the total value of the inertia moments of the motor shaft and the HarmonicDrive. *6: The resolution of the detector is the value obtained from ((motor shaft encoder resolution multiplied by 4) X (reduction ratio)). *7: The brush in DC servo motors requires replacement. *8: Please check the actuator rotation direction in our technical data sheet. 84
DC servo actuator Encoder Specification Item Model Output Circuit Resolution (Pulses / revolution) Power Supply (V) Current Consumption (ma) Response Frequency (khz) RH-5A RH-8D,11D,14D Line Driver Open Collector Line Driver Open Collector 36 1 DC 5V±5 DC 5V±5 DC 4.75 to 12.6V 17max. 6max. 17max. 6max. 1 125 Line Driver Output Circuit Open Collector Output Circuit Vcc=+4.75 to 12.6V Encoder Side IC: Am26LS32 or equivalent Encoder Side (+5V only for RH-5A) Line Driver Output Waveform Open Collector Output Waveform Phase A T=Average period T=Average period Phase A Phase B Phase B Phase Z Phase A Phase B Phase Z Phase Z Output shaft CW revolutions Output shaft CW revolutions Colors of Encoder Cables Model RH-5A RH-8D,11D,14D Cable Color Line Drive Open Collector Line Drive Open Collector Brown Blue COM Red Green COM Yellow Orange COM White Power Supply Power Supply Power Supply Power Supply Black Ground (COM) Ground (COM) Ground (COM) Ground (COM) Shield Floating Floating Floating Floating 85
RH Series Tachometer Generator Specification Specification Item Voltage Generated (Note1) Linearity (Note 1) Ripple (Note 1) Armature Resistance Armature Inductance Moment of Inertia (Note 2) V/1(r/min) %max %max mh gm 2 3±1% ±1 1(RHS)/3(P-P) 45±1%(2 ) 7±2% 12 1-4 Note 1: Value of tachometer generator only at 2rpm or higher. Note 2: Moment of inertia on motor shaft. When converted in terms of an actuator output shaft, the moment of inertia can be calculated by multiplying the reduction ratio R of the HarmonicDrive by the square. Polarity White Red (+) and (-) will be output to white and red cables respectively in CW revolutions when viewed from the actuator output shaft. Measurement circuit of generated voltage, linearity and ripple External Dimensions RH-5A (With incremental encoder) Motor Cable Encoder Cable 3-M2 tap hole Cross section B-B' RH-8D (With incremental encoder) Motor Cable Encoder Cable 86 * Please confirm dimensions and shape against the illustrated specifications issued by us accompanying the delivered product. The differential range may differ depending on the method for manufacturing parts (molded articles, machining articles). Contact us for the differential range of the size that is not described.
DC servo actuator External Dimensions RH-11D (With incremental encoder) Motor Cable Encoder Cable RH-14D (With incremental encoder) Motor Cable Encoder Cable RH-8D, RH-11D, RH-14D (With tachometer generator) Tachometer Generator Brush Cover * Please confirm dimensions and shape against the illustrated specifications issued by us accompanying the delivered product. The differential range may differ depending on the method for manufacturing parts (molded articles, machining articles). Contact us for the differential range of the size that is not described. 87
RH Series Positional Accuracy The uni-directional positional accuracy, repeatability and reverse positional accuracy are shown below. The following values represent typical values. (Source: JIS [Japanese Industrial Standards] B-621-1987). The RH series contains a speed reducer HarmonicDrive for precision control and positioning errors of the motor shaft are therefore compressed to 1/5 or 1/1 by speed reduction. In reality, angular transmission errors of the speed reducer determine the positional accuracy. The measured values of angular transmission errors of the speed reducer are therefore shown as the positional accuracies of the RH Series. The accuracies of the individual models are shown below. Item Model RH-5A RH-8D RH-11D RH-14D Uni-directional Positional Accuracy arc sec rad 29 1.31 1-3 15 7.27 1-4 12 5.82 1-4 12 5.82 1-4 Repeatability arc sec rad ±9 ±4.36 1-4 ±6 ±2.91 1-4 ±6 ±2.91 1-4 ±6 ±2.91 1-4 Reverse Positional Accuracy arc sec rad 15 7.27 1-4 6 2.91 1-4 6 2.91 1-4 6 2.91 1-4 <Measurement conditions, Load: no load, rotational speed: rated value> Mechanical Accuracy The mechanical accuracies of the output shaft and mounting flange of the RH series are as follows. Mechanical Accuracy Unit: mm Accuracy Item RH-5A RH-8D RH-11D RH-14D 1 Output shaft surface runout.3.3.3.3 2 Concentricity of output shaft and fitting part.4.4.4.4 3 Perpendicularity between the output shaft and mounting surface.4.4.4.4 Note: The aforementioned values are TIR (total indicator reading) values. 88
DC servo actuator Operable Range 5. Nm TORQUE.5 4..4 3..3 2..2 1..1 SPEED 12V 7. 6. 5. 4. 3. 2. 1..7.6.5.4.3.2.1 SPEED 12V 4 8 12 16 2 2 4 6 8 1 12.2.4.6.8 1..2.4.6.8 1. 1.2 8. 7. 6. 5. 4. 3. 2. 1..8.7.6.5.4.3.2.1 SPEED 12V 2 4 6 8 1 12.2.4.6.8 1. 1.2 3 25 2 15 1 5 3. 2.5 2. 1.5 1..5 2 4 6 8 1 4 35 3 25 2 15 1 5 4. 3.5 3. 2.5 2. 1.5 1..5 1 2 3 4 5.4.8 1.2 1.6 2..25.5.75 1. 1.25 5 4 3 2 1 5. 4. 3. 2. 1. 2 4 6 8 1 8 7 6 5 4 3 2 1 Nm TORQUE 8. 7. 6. 5. 4. 3. 2. 1. 1 2 3 4 5.5 1. 1.5 2. 2.5.5 1. 1.5 2. 2.5 14 12 1 8 6 4 2 Nm TORQUE 14. 12. 1. 8. 6. 4. 2. 2 4 6 8 1 2 16 12 8 4 2. 16. 12. 8. 4. 1 2 3 4 5 1.5 3. 4.5 6. 7.5 1 2 3 4 5 89
Tips for Selecting the Rotary Actuator Flowchart for Actuator Selection For horizontal linear motion W kgf Friction Coefficient JL JS w 2 Rotation motion P 2 kgm2 TL W P Nm 2 W kgf JL JS w 8 D 2 kgm 2 TL Nm JL kgm 2 TL μw r Nm r m D m Speed pattern NL NO Torque pattern T1 YES T2 t1 T3 t2 t3 t4 YES NO Tentative selection conditions Load Condition Check 3JA* Catalog Value Nm r/min kgm 2 Unit T1 TL T2 TL 2 6 T3 TL T1 TL JA JL NL t1 Trms T1 2 t1 T2 2 t2 T3 2 t3 t 9
Actuator Selection Example TL 2Nm TR 4.Nm NL 25r/min TR 3r/min JL.2kgm 2 JA.2kgm 2 Load Conditions Load rotational speed NL 25r/min Load torque TL 2Nm Moment of load inertia JL.2kgm 2 Speed pattern t1 t3.1sec t2.2sec t4.6sec 2 T1 2 6 3.Nm.2.2 25.1 Speed pattern NL 25r/min Torque pattern T1 T2 T3 t1.1 t2.2 t3.1 t4.6 T1 3.Nm T2 TL 2Nm T3 TL T1 TL 1Nm Trms 3 2.1 2 2.2 1 2.1 1 1.3Nm 91
Structure of HarmonicDrive Circular Spline Flex Spline Wave Generator Wave Generator: A ball bearing with thin-walled construction is fitted onto the outer circumference of an oval cam. The entire structure is oval. The inner ring of the bearing is fixed onto the oval cam and the outer ring elastically deforms through a ball. The wave generator can be mounted on a motor shaft. Flex Spline: A cup-like elastic metal part with thin wall thickness. Teeth are cut into the outer circumference of the opening of the cup, from where the output is usually extracted. Circular Spline: The inner gear of the rigid body, with teeth of equivalent size to those on the flex spline cut into the inner circumference. The circular spline has two more teeth than the flex spline and is normally fixed onto the gear casing. Three basic components are assembled Teeth meshing Flex Spline Circular Spline Wave Generator Circular Spline Flex Spline Continued on page 14 92