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Anti-Backlash Actuators (Imperial)

      

Anti-Backlash Actuators (Imperial)

Anti-Backlash Actuator Anti-backlash actuators reduce vertical backlash resulting in smooth, precise operation and minimal wear. Backlash occurs when the motor driving an actuator reverses its load direction. Since there is a gap between the lifting screw and the worm gear threads detrimental screw movement may occur. When the actuator is under load, the lifting screws¿ threads are supported by the worm gears threads. The anti-backlash nut, being pinned by to the worm gear and being adjusted downwards by the shell cap, forces the bottom thread surfaces against the upper thread surfaces of the lifting screw. Thus backlash between the lifting screw and worm gear threads is reduced to a minimum.
  • The Duff Norton Anti-backlash design features a separate anti-backlash nut and reduces actuator backlash to less than 1 thousandths
  • Available in Stainless Steel 
  • Anti-backlash nuts reduce worm gear wear
  • Anti-backlash nuts act as additional load safety devices when the worm gear has become worn
          

Anti-Backlash Actuator Performance Specifications (Imperial)
Performance Table Instructions
When reviewing any Duff-Norton Actuator Performance Specifications Table, as part of the process of selecting the best-suited actuator for your application, there are several important worm-gear ratios to consider.
  • Standard Ratio - is frequently chosen when higher speeds and efficiency ratings are desired.
  • Optional Ratio(s) - is frequently chosen when the application requires higher lifting capacities, lower speeds, or to ease the use of a handwheel.
  • Numeric Ratio - is frequently chosen for applications requiring fine adjustments, higher lifting capacities, lower speeds, the easy use of a handwheel, self locking applications, and also offers the benefit of an even number of worm input turns per inch of stroke.
Capacity (Tons) 1/4 1/2123510152025355075100150
Max. Speed Cface Driven (in/min)** (pg. 114)¿¿¿72.072.0108.0108.0108.0108.0107.5107.5¿¿¿¿
Max. Speed Red. Driven (in/min)** (pg. 106-107)¿¿¿14.414.421.921.921.921.922.222.412.2¿¿¿
Lifting Screw Diameter (in) 1/2 5/8 3/4111 1/222 1/42 1/233 3/44 1/2567
Pitch (in)0.2500.1250.2000.2500.2500.3750.5000.5000.5000.6660.6660.6660.6660.7501.000
TypeACMEACMEACMEACMEACMEACMEACMEACMEACMEACMEACMEMod. Sq.Mod. Sq.Mod. Sq.Mod. Sq.
Worm Gear RatiosStd.5:15:15:16:16:16:18:18:18:110 2/3:110 2/3:110 2/3:110 2/3:112:112:1
Optional No. 1¿¿20:124:124:124:124:124:124:132:132:132:136:136:136:1
Optional No. 2¿¿¿12:112:112:1¿¿¿¿¿¿¿¿¿
Turns of Worm for 1" StrokeStd.204025242416161616161616161612
Optional No. 1¿¿100969664484848484848484836
Optional No. 2¿¿¿484832¿¿¿¿¿¿¿¿¿
Worm Torque at No Load (in-lb)Std.22555102020304050100150200250
Optional No. 1¿¿555102020304050100150200250
Optional No. 2¿¿¿5510¿¿¿¿¿¿¿¿¿
Maximum Horsepower per ActuatorStd. 1/3 1/3 1/22245558815152525
Optional No. 1¿¿ 1/4 1/2 3/4 3/41 1/21 1/21 1/22 1/22 1/2661111
Optional No. 2¿¿¿ 3/41 1/42¿¿¿¿¿¿¿¿¿
Worm Torque at Full Load (in-lb)Std.14236113218149582515732255297044008250132001760030921
Optional No. 1¿¿28558220444090212871870264046207095946017050
Optional No. 2¿¿¿82115303¿¿¿¿¿¿¿¿¿
Efficiency Rating (%)Std.27.817.221.020.122.020.124.119.017.616.715.812.111.311.312.9
Optional No. 1¿¿11.612.112.112.215.111.010.38.98.87.27.07.07.8
Optional No. 2¿¿¿16.117.216.4¿¿¿¿¿¿¿¿¿
Weight with 6" Stroke (Raise) (lb)2.32.35171735526693160240410120012001350
Weight per Additional 1'' Stroke (Raise) (lb)0.10.10.30.30.30.91.41.52.62.53.75.59.09.012.6
Key Torque (in-lb)40701754606701750470075801062514000265004711088650118200216000
Max Worm Speed at Full Load (rpm)Std.1469909521955696509382200140170115115729051
Optional No. 1¿¿57357357323221510573846082537341
Optional No. 2¿¿¿573682416¿¿¿¿¿¿¿¿¿
Max Load at Full Horsepower and 1750 rpm (lb)Std.407474469211222852764397830922698423438325402448580506361
Optional No. 1¿¿3561041170587916201157764136710822568142742372610
Optional No. 2¿¿¿113621742119¿¿¿¿¿¿¿¿¿
*For loads from 25% to 100% of the actuator capacity, torque requirements are approximately proportional to the load.
**Speed is a function of how the actuator is driven. Please see the "Motorized Performance" verticle tab to your screen¿s left.