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Entry type: Product note Entry ID: 109750640, Entry date: 06/07/2018

SIMOGEAR input unit A - Sales release

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For the majority of applications, directly mounting the motor on the gear unit is the optimal solution when it comes to compactness and weight. However, as this is not possible in all cases, SIMOGEAR gear units can also be fitted with an input unit.


The SIMOGEAR input unit A with additional input shaft is designed for flexible solutions where the motor is mounted separately from the gearbox via

  • belt pulleys,
  • chain
  • wheels or


Input group A could be used in the following cases:

  • Restricted installation space: Total length requires separation of motor and gear unit -> belt drive.
  • Driving of multiple gear units with a single motor: One motor drives multiple identical drives via belt drives.
  • Cooling tower drives: Motor must be outside of the "wet area".
  • Larger drives with hydraulic couplings: Soft start (not electrical) via hydraulic couplings (e.g. Flender Fludex).


The drive groups with an additional drive shaft are available in sizes 80 to 250.

The following versions have to be distinguished between:

  • Input unit A without centering and without threaded holes on the input-side flange.
  • Input unit AZ with centering and threaded holes.

Overview of sizes

Comparison of SIMOGEAR input group A and MOTOX-N solution

The following diagrams represent a direct comparison of the SIMOGEAR and MOTOX-N solutions.

Comparison with MOTOX-N

Comparison with MOTOX-N - Dimensions

Advantages of SIMOGEAR input group A

Input group A offers the following advantages compared to MOTOX-N:

  • more compact, lighter design compared with MOTOX-N solution with the same efficiency and lifetime.
  • higher permitted radial forces and torques on the drive shaft.


A piggy back design will no longer be available for SIMOGEAR. If required, MOTOX-N 2nd Life can be ordered as a replacement for MOTOX-N via the Quotation Center.
Please also note that SIMOGEAR input unit A is not available with backstop.

Tools and documentation

The SIMOGEAR input unit A is included in the DT Configurator.

DT Configurator


The "9" at the twelfth digit of the article number refers to the input unit A or AZ.

The following order codes refer to the different versions:

  • M1A: Input unit A with additional input shaft
  • M1B: Input unit AZ with additional input shaft and motor bracket

Example: 2KJ3-xxxx-xxx9 + M1

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