Gears & Mechanics

We supply gear drives for almost all of our motor categories from high precision through to the industrial kilowatt ranges. Using a gear drive will provide you with more torque and strength to manage your application.

Selecting your gearbox

What you will need to know is the best type of ratio for your application. Inertia capability, speed reduction, torque multiplication and mechanical strength could be optimised with gearbox.

Gearboxes used with electric motors
Electric motors are available with a number of technology advantages (depending on the application) when connected to gearboxes. Positioning, constant speed and adjustable speed are the main application features. Some motors can be designed to operate at low speeds (less than 1,000 RPM), so a gearbox may not be necessary.

High Precision Gear Drives

High Precision Gearbox
High Precision

Some of the finest companies in the world involved in aerospace, aeronautics, robotics, servo mechanisms and machine tool manufacturing have selected our range of precision engineered gearboxes.

High precision applications may not tolerate the inherent backlash of worm, bevel, helical or spur gears.
For accurate positioning and robotic applications, low backlash is often required.
High precision gear reducing is managed with designs such as planetary or harmonic constructions.

These very compact gearboxes have exceptional abilities: great torsional strength, low inertia of rotating parts, high number of gear ratios available and long life under the most severe conditions.


  • Number of starts for 15,000 hours: 3,600 starts/hour
  • Torque: 3 times the rated torque
  • Gear ratios:
    • 55 ratios from 3:1 to 10,000:1 in 3 stages
    • 129 ratios from 3:1 to 10,000:1 in 4 stages
    Input and output shafts rotate in the same direction.
  • Output shaft end play depends on precision class reference:
    • Class 0: on request
    • Class 1: endplay <= 1 min
    • Class 3: endplay <= 3 min
    • Class 5: endplay <= 5 min
    • Class 12: endplay <= 12 min
  • Peak admissible temperature: 150°C
  • Lubrication: Our designs benefit from synthetic oil with viscosity 150 (Klüber GH6-150 is recommended).
    For specific operating conditions, oil viscosity can be adapted.
  • Continuous duty operation subject to engineering review.

Various types of gearboxes:

  • SUMERSA NR80, NR110, NR140, NR180, NR210, NR240, NR350
  • ALPlanetary AL100
  • PRPlanetary PR180, PR240
  • ST-Stepper ST65
  • PRA-Right angle

Specification tables for other types of gearbox are available on request.

Using gearheads with A.C. and D.C. servo motors or stepper motors provides excellent resolution, accurate positioning, speed reduction, matched inertia and torque multiplication. The designs and engineering construction ensure that the transmitted torque is distributed very smoothly, so that minimum to zero losses occur through the effects of friction, providing exceptionally high efficiency. Servo systems in particular use motors with high speed, high torque, low inertia characteristics, so when they are coupled with planetary drives, the output torque can be enhanced, load inertia reduced and some shock loading advantages can be achieved, maintaining the high performance necessary for servo transmissions.


  • High efficiency +90%
  • Very compact • multi reduction ratio • all sizes
  • Micro second acceleration & deceleration
  • High output torque
  • High axial and radial loads
  • Low inertia • rugged construction
  • Servo inputs (high speeds)
  • Mounting in all configurations
  • Low backlash
  • Accurate response in robotic applications

We can customise your high precision geardrive and, for servo and stepper motor applications, ensure that the performance for high torque, low backlash and efficiency are optimised for exact results.
Geardrives are available in parallel or right angle frames and many ratios are available as standard, with customised ratio options offered after engineering approval.

Selecting industrial gear reducers for electric motors

Once you have selected the speed and torque that is required for your system/machine application, the next step is to determine if a gearbox is necessary and, if so, the best type of gearbox and ratio for your needs. Spur, bevel and helical gears are much more efficient than worm gears, although if noise is a concern in an application, the worm design is often a good selection.


To further develop any transmission solution, a full range of options can be considered to complement the electronics, motors & gearboxes.

We have prepared a range of suitable clutches, brakes, torque limiters, linear actuators, couplings, bushings and locking connectors, special gears and treatments.

Clutches • Electromagnetic D.C. voltages
• Particle (magnetic) clutches
• Clutch/brake assembly
Brakes • Spring brakes

D.C. brakes fit directly onto shaft, pulley, gear, sprocket, disc or other drivers that need to be braked.
Torque limiters Various mechanical options for T.L. are available:
• Friction type
• Ball race
• Roller race
• etc.

Available with mounting adapters.

For selection, indicate:

  • Torque required
  • Shaft size
  • Speed range
  • Mechanical protection required
Linear actuators Small D.C. through to heavy duty kW

For selection, indicate:

  • Duty cycle
  • Type of motor
  • Stroke/limits
  • Linear speed
  • Environment
  • Supply/power
  • Load details
  • Force/shock
Couplings & Connectors • Pulleys & belts
• Flexible couplings – with or without backlash
• Disc couplings
• Universal joints
• Geared couplings
• Jaw couplings
• Locking rings
• Bushes
• Beam couplings

Call us or write to for selection information and assistance with mechanics.