High Gear Ratio M8 Rotary Incremental Actuator

The Moog High Torque M8 rotary incremental actuator is a compact, closely integrated design made up of two key elements: a motor and a multi-stage speed reducer. The motor is a small angle permanent magnet stepper with relatively high holding torque. The multi-stage speed reducer offers a large reduction ratio (6400:1), low weight, and high torsional stiffness. Co-axial nesting of the motor and transmission drive elements gives the unit low profile geometry. The actuator can be made available in two and three phase motors with optional features such as potentiometer/resolver output position feedback. All the electrical elements such as motors and position sensors can be redundant with little or no change in actuator envelope.



Key Features:

  • Very compact coaxial design
  • Incorporates multi-stage gear system providing up to 6400:1 reduction
  • Low weight
  • Low backlash
  • High torsional stiffness



Description Units Basis Data

Output Step Angle

Degrees Standard   0.0030
Steps Revolution Steps Standard  122,880
Harmonic Drive Ratio - Standard 5,120:1
Motor Step Angle Degrees Standard  15
Max. Output Step Rate Step/sec (Deg/sec) Maximum 690 (1.92)
Torsional Stiffness Lb-in/rad Standard 3,440
Shaft Load Capability Axial lbf Maximum 170
Transverse lbf Maximum 240
Moment Lb-in Maximum 100
Output Torque Lb-in Maximum 360
Unpowered Holding Torque Lb-in Maximum 160
Body Diameter Inch Standard 1.400
Body Length Inch Standard 4.25
Power Watts Maximum 10
Through-hole Capability Inch Maximum 0.120

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