20:1 planetary gearbox for servo or stepper drivetrains
The GBX0400201401F is a 40 mm-diameter planetary gearbox with a 20:1 reduction ratio, designed to match the output of a servo or stepper motor to the speed and torque requirements of a positioning or indexing axis. Efficiency is 94 %, meaning about 6 % of the input power is lost as heat in the gear train — relevant for thermal budgeting in a compact enclosure where the gearbox is mounted close to the motor.
Torque, backlash, and load ratings for axis design
Maximum torsional backlash is 28 arc.min — this is the angular play at the output shaft when the input reverses direction, a key number for positioning accuracy in pick-and-place or rotary indexing where the load must stop within a fraction of a degree. Maximum radial force at the output shaft is 200 N at 100 rpm for a 10,000-hour L10 life, dropping to 160 N for 30,000 hours — the radial load rating applies at mid-shaft, so an overhung pulley or sprocket reduces the allowable force proportionally. Maximum axial force (push or pull on the shaft) is 200 N at 100 rpm for 10,000 hours, 160 N for 30,000 hours — axial loads from a helical pinion or a thrust collar must stay within these limits to avoid bearing fatigue. Torsional rigidity is 1.1 N.m/arcmin — this stiffness value tells you how much the output shaft twists under load; for a 20 N.m continuous torque the wind-up is about 18 arcmin, which adds to the backlash when the load is applied in one direction.
Obsolete — sourced through independent channels
Available through independent surplus and broker channels; quantities are lot-specific and confirmed at RFQ. No pin-compatible or drop-in replacement is offered by the original manufacturer, so a BOM revision or a different frame size may be needed for a new-build design.
Mounting and environmental fit
The gearbox housing is black anodized aluminium, 40 mm outer diameter — fits standard NEMA 17 or 23 motor flanges with the appropriate adapter bracket; the output shaft is C45 steel, lubricated for life with no maintenance ports. Noise level is 55 dB at 1 m, no-load — quiet enough for a lab or assembly cell, but the actual noise under load will be higher depending on the motor speed and the mounting structure's resonance.