HARMOIC GEARHEAD exen s revolutionary (HG) is the perfect combination of size and precision. Use the integrated with exen s RPS Pinion (HGP) to create a true backlash-free solution from the motor to the driven load. With up to a 7% reduction in length over standard gearheads, machine designers will appreciate the opportunities available with this space saving product. Features & Benefits... 52 Specifications... 53 PATETED Selection Process Cycle Determination... 54 Stiffness... 55 Output Loading... 56 57 Efficiency... 58 Dimensional Drawings... 59 Life Graphs... 6 Input Motor... 6 HGP Preloader... 61 62 51 Harmonic Gearhead
The exen Advantage exen s patent pending (HG) offers a precision drive solution that overcomes the challenges of existing gearing methods. This new technology eliminates problems with backlash that have plagued the motion control industry, offering reliable precision even when intricate movements are required. In the tradition of exen's entire line of precision motion control products, the sets new standards with these great features: Zero Backlash High Positional Accuracy & Repeatability Quiet Operation Large, Rugged Cross-Roller Output Bearing Compact Save 7% or more in gearhead length. HGP Standard Two- Stage Planetary with Pinion Save space by taking advantage of exen s Harmonic Gearhead with Pinion (HGP). In this model, the RPS pinion comes fully integrated into the gearhead, creating the only drive solution that maintains zero backlash from the driving motor shaft through to the driven load for both linear and rotary motion. Features & Benefits DRIVIG TECHOLOGY I ADVACIG MARKETS exen s HG(P) utilizes Harmonic Strain-Wave Technology made up of a circular spline, flex-spline and wave generator. As these components rotate, their unique shape and tooth profile allow 3% of the teeth to be engaged simultaneously for: Smooth Rotation High Torque Zero Backlash The effortless, low-stress meshing of the circular spline and flex-spline teeth results in a long gearhead life with reliable, quiet operation. Some operators call this peace of mind. Aerospace Robotics Semiconductor Factory Automation Medical / Surgical 52
Specifications HARMOIC GEARHEAD (HG) Specifications HG17 HG25 HG32 HG5 Gear Ratio 5:1 8:1 1:1 12:1 5:1 8:1 1:1 12:1 5:1 8:1 1:1 12:1 8:1 1:1 12:1 Max Acceleration Torque 1 m 35 35 51 51 72 113 14 14 14 217 281 281 675 866 157 Max Average Torque 1 m 25 3 35 35 51 85 9 9 1 153 178 178 484 611 688 Inertia at Input kg-cm 2.1959.1954.1952.1952.7522.753.7498.7496 2.6294 2.6236 2.6222 2.6215 2.485 2.467 2.457 Backlash ArcSec One Way Accuracy ±ArcSec 45 45 45 45 One Way Repeatability ±ArcSec 1 1 1 1 Weight kg 1.4 2.6 5.2 2. Product umber 969 9691 9692 9693 9694 96941 96942 96943 9696 96961 96962 96963 9691 96911 96912 HARMOIC GEARHEAD WITH PIIO (HGP) Specifications HGP17 HGP25 HGP32 HGP5 Torque (m) Integrated Pinion Size RPS16 RPS2 RPS25 RPS4 Gear Ratio 5:1 8:1 1:1 12:1 5:1 8:1 1:1 12:1 5:1 8:1 1:1 12:1 8:1 1:1 12:1 Max 35 35 51 51 72 92 92 92 14 159 159 159 458 Acceleration 1 Thrust () 1374 1374 23 23 2262 29 29 29 3519 4 4 4 6 Torque (m) 25 3 35 35 51 85 9 9 1 153 159 159 458 Max Average 1 Thrust () 982 1178 1374 1374 162 267 2827 2827 2513 3845 4 4 6 Inertia at Input kg-cm 2.1971.1958.1955.1954.7538.759.752.7499 2.6326 2.6248 2.623 2.6221 2.518 2.488 2.471 Backlash μm One Way Accuracy ± μm 25 25 25 25 One Way Repeatability ± μm 7.5 7.5 7.5 7.5 Weight kg 1.7 3. 5.8 24.8 Product umber 9691 96911 96912 96913 9695 96951 96952 96953 9697 96971 96972 96973 96911 969111 969112 GEERAL SPECIFICATIOS FOR BOTH HG & HGP UITS Specifications Size 17 Size 25 Size 32 Size 5 cyclic RPM 73 56 48 35 Max Input Speed 1 continuous RPM 365 35 35 25 Max Average Input Speed 1 RPM 365 35 35 25 Max Input Acceleration Rate rad/sec 2 51 39 335 245 Efficiency @ Max Average Torque (E T_max ) 8% ±5% Stiffness, Hysteresis Output Loading Temperature Limits Mounting Position Direction of Rotation Lubrication Life See Stiffness Section See Output Loading Section Ambient Temperature: ºC to +4ºC Maximum Unit Temperature: < 9ºC o Restriction Motor Opposite Gearhead Lubricated for Life See HG & HGP Life Section Specifications 1 Refer to the Selection Process section for product sizing procedures. ote: All accuracy data taken at 2% of maximum load. 53
Selection Process When selecting the proper, use the Specifications table to determine the HG/HGP size that best fits the application s torque, speed and physical size requirements. Then, use the following calculation sections to evaluate whether the cycle type, stiffness, efficiency and bearing load capacity of the selected HG/HGP size meets all the application requirements. HG/HGP Cycle Determination Correct sizing of the is critical to the proper function and life expectancy of your unit. The following section provides information regarding cycle type to be used in the gearhead sizing process. The two Cycle Types are: Continuous Motion & Cyclic Motion STEP 1: Determine which Cycle Type applies to your application. STEP 2: Use the Cycle Limitations information to correctly size the Gearhead. COTIUOUS MOTIO: single direction motion lasting longer than one hour Cycle Limitations Example Cycle Input Speed Max average input speed Output Torque Max average torque IPUT SPEED V MAX.5 1 Time (hr) LOAD TORQUE T MAX.5 1 Time (hr) CYCLIC MOTIO: reversing direction motion Cycle Limitations Example Cycle Cycle Types Input Speed Output Torque Time at Max Input Speed <1 seconds (t 2 ) Time above Max Average Input Speed <3 seconds (t 1 ) Average over any 2 minutes < Max Average Input Speed Time at Max Acceleration Torque <1 seconds (t 3 ) Time above Max Average Torque <1 seconds Average over any 2 minutes < Max Average Torque LOAD TORQUE IPUT SPEED V MAX V AVG V AVG V MAX T MAX t3 T AVG T AVG T MAX Accel t1 t2 Operating Decel 1 2 1 2 Time (min) Time (min) 54
HG/HGP Torsional Stiffness Unlike many other gearing types, stiffness is non-linear. As torque increases, stiffness also increases, as shown in the graph below. OTE: If you wish to calculate "windup" at torque greater than T1, remember to include the displacement caused by lower stiffness regions. HG STIFFESS HYSTERESIS Hysteresis HYSTERESIS K3 D 3 D 2 K 2 -T +T D 1 K 1 T 1 T2 T 3 HG AD HGP STIFFESS DATA Torsional stiffness is determined by applying a torque to the output of the gearhead while the input is held from rotation. For ease of calculation, the slope of the curve is approximated using three straight lines representing stiffness values K 1, K 2, & K 3. Refer to the tables below for the typical stiffness values for each size HG and HGP. Reference Torque (m) Ref. Disp. (ArcMin) Stiffness (m/arcmin) 5:1 8:1 + 5:1 8:1 + Reference Torque (m) Ref. Disp. (ArcMin) Stiffness (m/arcmin) 5:1 8:1 + 5:1 8:1 + Size 17 T 1 3.9 D 1 1.66 1.44 K 1 2.36 2.7 T 2 8. D 2 2.94 2.81 K 2 3.2 3. T 3 35. D 3 1.8 1.99 K 3 3.78 3.3 Size 32 T 1 52. D 1 3.11 2.81 K 1 16.7 18.5 T 2 18. D 2 6.6 4.81 K 2 19. 28. T 3 178. D 3 8.52 6.93 K 3 28.5 33. Size 25 T 1 14. D 1 2. 2.12 K 1 7. 6.6 T 2 48. D 2 6.53 6.98 K 2 7.5 7. T 3 9 D 3 11.2 11.98 K 3 9. 8.4 Size 5 T 1 18. D 1 1.66 K 1 65. T 2 382. D 2 A 5.81 K 2 A 66. T 3 688. D 3 1.38 K 3 67. HYSTERESIS Hysteresis is measured by applying maximum average torque in both directions on the output with the input locked. Typical values are provided in the table to the right. Hysteresis (ArcSec) Size 17 Size 25 Size 32 Size 5 9 9 6 6 Stiffness 55
HG Output Loading s come equipped with a cross roller bearing on the output, offering high precision and large, load-carrying capabilities. Use the following information to verify that the selected gearhead meets all application load requirements. F R Table 9 Output Load Ratings Table HG(P)17 HG(P)25 HG(P)32 HG(P)5 Bearing Constant (C B) m -1 31.25 23.81 18.52 11.9 F A_sup Bearing Center Distance to Flange (L) m.185.255.29.425 Max Axial Suspended Load (F A_sus_max) 45 11 155 45 Max Axial Supported Load (F A_sup_max) 11 117 19 454 Max Radial Load (F R_max) 222 318 422 122 Max Moment Load (T M_max) m 215 335 69 255 Max Combined Load (P C_max) 68 79 128 345 F A_sus T M L Single vs. Multiple Load Direction Single Loading Direction If only one loading direction applies to your application, simply compare the maximum application load with the HG ratings above to ensure that the gearhead is capable of withstanding the application load. Multiple Loading directions When two or more loading directions apply, calculate the combined load using radial, axial and moment load values. Record your application data and perform the calculations on the following page to determine the Combined Load (P C ) of your application. Then compare this value with the Max Combined Load in Table 9 above. OTE: Although Combined Load is calculated using average loads, no load should exceed the maximum rated load for that loading direction. Output Loading 56
HG Output Loading (continued) CALCULATIG COMBIED LOAD REQUIREMETS Refer to the explainations and data on the preceding page to complete the following calculations to determine the combined load requirements of your application. STEP 1: GATHER APPLICATIO DATA Axial (F A ), Radial (F R ), and Moment (T M ) Loads are application specific. Use the table below to record the average loads that the gearhead will be subjected to during operation. Application Loads Required for Gearhead Selection Average Axial Load (F A) [Either suspended (FA_sus) or supported (FA_sup), whichever is present in your application] Customer Application Data (record your values below) Sample Data (HG25) 1 (F A_sup) Average Radial Load (F R) 5 Sample Application FR = 5 FA = 1.5 m Average Moment Load (T M) m 25 m STEP 2: CALCULATE COMBIED LOAD O BEARIG Calculating a Combined Load simplifies a complex load scenario into a single value that characterizes the application and can be compared to the Maximum Combined Load (P C_max ) in the ratings table. Follow the steps below to find the Combined Load that characterizes your application. Radial/Moment Load (F RM ): F RM = F R + (C B T M ) F RM = Sample: F RM = 5 + (23.81 m -1 25 m) = 6452.5 + m -1 m Radial/Moment Load (F RM) F RM = Use this table to determine the correct value for X & Y to be used in the Combined Load equation below. F A F RM = = IF: X THE: F A F RM < 1.5 1.45 F A F RM > 1.5.67.67 Y Sample: 1 6452.5 =.155 So, X = 1 & Y =.45 Combined Load (P C ): P C = (X F RM ) + (Y F A ) P C = Sample: P C = (1 6452.5 ) + (.45 1 ) = 692.5 STEP 3: VERIFY APPROPRIATE HG SIZE Compare the calculated Combined Load (P C ) value with the Max Combined Load (P C_max ) found in Table 9 to verify whether the selected HG size meets your application load requirements. OTE: Consult exen if application subjects the HG output to significant vibrations or impact loading. + P C = Combined Load (P C) Output Loading 57
HG / HGP Efficiency Gearhead efficiency is dependent on many factors, including temperature, speed, torque, and lubrication type. However, the biggest contributor to efficiency loss is running torque, therefore the following calculations focus on your application torque. As is true with any system, efficiency calculations are merely estimations and should be treated as such. STEP 1: CALCULATE THE TORQUE RATIO To find the Torque Ratio, divide your application torque by the maximum average torque. a. Refer to the HG Specifications Table to find max average torque values. b. Determine the torque on which you want to base your efficiency ratings. Application Torque (Tap) Max Torque (Tmax) Sample: 12 m Sample: 25 m Torque Ratio Torque Ratio: R = Sample: R = 12 25 =.48 T AP R = R = T max STEP 2: FID THE EFFICIECY COMPESATIO COEFFICIET (C E ) Use the graph below to determine the Compensation Coefficient (C E ). a. Mark on the x-axis the Torque Ratio (R) value calculated in Step One. b. Draw a vertical line from this point until it intersects the curve. c. From the intersection point marked on the curve, draw a horizontal line to the y-axis. d. Record the value at this y-axis intersection point as the Compensation Coefficient (C E ). EFFICIECY COMPESATIO COEFFICIET GRAPH Efficiency COMPESATIO COEFFICIET (CE) 1.9.8.7.6.5.4.3.1.2.3.4.5.6.7.8.9 1 TORQUE RATIO (R) Sample Compensation Coefficient STEP 3: CALCULATE EXPECTED APPLICATIO EFFICIECY To find the expected efficiency at your application torque, simply multiply the Efficiency Compensation Coefficient (C E ) by the Efficiency at Max Torque (E T_max ). a. Refer to the HG Specifications table to find the E T_max value and record it in the equation below. C E = Sample: C E =.88 Expected Application Efficiency Expected Application Efficiency: E A = C E E T_max E A = % E A = % Sample: E A =.88 8% = 7.4% 58
Dimensional Drawings SAMPLE IPUT COFIGURATIO Input will be configured for user servomotor. All dimensions shown in mm. Motor Dimensions HG & HGP Input G E K H F A D I J B C Max Shaft Length HG/HGP A B C (max) D E F G H I (h7) J (h7) K Size 17 Ø4 1.5 2.5 31. Ø9. M4 x.7 (12 holes) Ø86. M4 x.7 (4 holes) Ø63. Ø92. Ø75. 24. Size 25 Ø6 2. 3. 36.5 Ø14. M4 x.7 (12 holes) Ø17. M5 x.8 (4 holes) Ø75. Ø115. Ø99. 21.5 Size 32 Ø8 2.5 3.5 48. Ø19. M5 x.8 (12 holes) Ø138. M6 x 1. (4 holes) Ø1. Ø148. Ø125. 29. Size 5 Ø13 2.5 4.2 64. Ø32. M8 x 1.25 (12 holes) Ø212. M1 x 1.5 (4 holes) Ø165. Ø225. Ø195. 41.25 OUTPUT COFIGURATIO All dimensions shown in mm. HGP Output HG Output L M R S U Pilot Depth P Q V W SIZE L M HGP17 79.8 34.8 Ø67. HGP25 87.8 4.5 Ø84. HGP32 17. 47.5 Ø11. HGP5 179.5 86.5 Ø19. HG17 Ø5. 5. HG25 Ø6. 6. HG32 Ø6. 6. HG5 Ø1. 1. T O (H7) P Q R S T U V (H7) W (h8) M5 x.8 Ø31.5 52. 7. 6.13 4. Ø2. Ø4. 7 Holes M6 x 1. Ø5. 6.3 13. 6.5 6. Ø31.5 Ø63. 7 Holes M6 x 1. Ø63. 74. 14.5 6.5 6. Ø4. Ø8. 11 Holes M1 x 1.5 Ø125. 18.3 15.3 8.5 8. Ø8. Ø16. 11 Holes O Dimensions 59
HG & HGP Life life is based on average output torque and ratio. Output Torque (m) 4 35 3 25 2 15 1 5 HG/HGP 17 Life 1 2 3 4 5 6 7 8 Output Revolutions (Million) RATIO 5:1 8:1 1:1 12:1 Output Torque (m) 1 9 8 7 6 5 4 3 2 1 HG/HGP 25 Life 1 2 3 4 5 6 7 8 Output Revolutions (Million) RATIO 5:1 8:1 1:1 12:1 Output Torque (m) HG/HGP 32 Life 2 18 5:1 16 8:1 14 1:1 12 12:1 1 8 6 4 2 1 2 3 4 5 6 7 8 Output Revolutions (Million) RATIO Output Torque (m) 8 7 6 5 4 3 2 1 HG/HGP 5 Life 1 2 3 4 5 Output Revolutions (Million) RATIO 8:1 1:1 12:1 Input Motor Recommendations Allowable Motor Tilting Torque Allowable motor tilting torque is defined as the combination of static and dynamic force acting through the motor's center of gravity, multiplied by the distance (d CG) to the HG motor adaptor mounting face. OTE: DO OT subject the input coupling to an overhung load (example: pulley, sheave, etc.). HG(P) Size Torque (m) 17 2 25 4 32 8 5 2 d CG F Life & Input Motor Input Sealing A gasket seal is positioned between the motor adaptor and the motor pilot to help seal the HG product from external dust and debris. Be sure to use a properly sized servo motor input flange. A servo motor with an oil seal on the output shaft is recommended. OTE: Consult exen in the following situations: a) before using a motor with an interrupted pilot; b) applications in which liquids or excessive dust are present and may ingress into the product. Heat Dissipation To dissipate heat generated by the motor, exen recommends mounting the gearhead to a machine frame or heat sink. Refer to the table at the right for aluminum heat sink plate sizes used in testing by exen. Heat Sink Surface Area (m 2 ) HG(P)17 HG(P)25 HG(P)32 HG(P)5.11.14.14.27 6
HGP Preloader Pair exen s with our HG Preloader for easy integration into your machine design. Preloaders feature an adjuster that allows the HGP to be moved up or down into the rack while keeping the pinion properly oriented to the rack. Preloader components are made of an alloy steel with a corrosion-resistant nickel finish. High-Precision Ground Surfaces Allows Perpendicular Movement Corrosion Resistant Materials HGP Preloader Customer Machine Frame HGP Preloader Dimensional Drawings HGP17 Product umber 9687 Preloader Details M4 X.7 2 Screws M4 X.7 12 Screws (ø113.7) ø86. ø76. 3º TYP R8. 4X 55. 35. 11. Hex 3 mm Wrench 8. 55. 133.8 Max ( 126.8 Min) 115. M6 X 1. (4X) Shoulder Cap Screws with Washers Customer- Mounting Surface see View to Right 8.5 2X 4.3 Gearhead & Pinion Shown for Reference ot Included 71.3 ø1. M6 X 1., 13.5 MI ø8.13 ±.13, 4. 4 Holes Located as Shown 44. 88.±.5 25. 12.5 All dimensions shown in mm. Customer Mounting Surface Details M4 X.7 7.5 MI 2 Holes Located as Shown 36. (2X) 36. (2X) Mounting Surface.3 1.6 Preloader 61
HGP Preloader Dimensional Drawings (continued) HGP25 Product umber 96872 Preloader Details M6 X 1. 2 Screws M4 X.7 12 Screws ø17. (ø142.95) 3º TYP 5. Hex 8 mm Wrench 12.7 135. 12. 2X 6. 16. Max ( 153. Min) Customer- Mounting Surface See View to Right 89.19 M8 X 1.25, 15.5 MI ø1.13 ±.13, 4. 4 Holes Located as Shown 3. 15. All dimensions shown in mm. Customer Mounting Surface Details M6 X 1., 8. MI 2 Holes Located as Shown 48.5 (2X).3 1.6 ø1. R8. 4X 62.5 125. 61. M8 X 1.25 (4X) Shoulder Cap Screws with Washers Gearhead & Pinion Shown for Reference ot Included ø123. 52.5 15. ±.5 48.5 (2X) Mounting Surface HGP32 Product umber 96873 Preloader Details M6 X 1. 2 Screws M5 X.8 12 Screws 138. 126. 3 TYP R8. 4X 8. 16. 5. Hex 8 mm Wrench 12.7 9. 18. Customer- Mounting Surface See View to Right 12. (2X) 6. ( ) 25. Max 198. Min M8 X 1.25 (4X) Shoulder Cap Screws with Washers Gearhead & Pinion Shown for Reference ot Included Customer Mounting Surface Details M8 X 1.25, 15.5 MI M6 X 1., 1.13±.13, 4. 8. MI 6 Holes Located 2 Holes as Shown Located 3. as Shown 15. 31.±.5 15.15 28. 71.5 48.5 156. 7. 14.±.5 48.5 71.5 28. 19.±.5 1.6 Mounting Surface.3 Preloader HGP5 Product umber 96875 Preloader Details M6 X 1. 2 Screws M8 X 1.25 12 Screws 212. 3 TYP 196. R12. 4X 12. 24. 5. Hex 8 mm Wrench 12.7 13. 26. 14. (2X) 285. Max ( 278. Min) M8 X 1.25 (4X) Shoulder Cap Screws with Washers 7. Customer- Mounting Surface See View to Right Gearhead & Pinion Shown for Reference ot Included Customer Mounting Surface Details 145.15 233. 4.±.5 15. 3. 15. 17.±.5 21.±.5 M6 X 1., 8. MI 2 Holes Located as Shown 83.5 32..3 1.6 83.5 Mounting Surface 32. M1 X 1.5, 22. MI 12.13±.13, 4.13 8 Holes Located as Shown 62