Thomson Worm Gear Screw Jacks

MULI®, JUMBO® spindle, stroke, helical gear units are a symbol of reliability and versatility. The technically sophisticated, easy-to-install rectangular housing can be easily extended to extensive lifting systems with a wide range of accessories. Another important part of the THOMSON spindle gearboxes is the precision drive with trapezoidal or ball screw of its own production, which is characterized by high quality.

  • The wide portfolio offers a wide range of gear types and sizes that allow heavy loads to be moved at high speeds.
  • Thoroughly controlled quality of the components used, optimized production and service of THOMSON BUSINESS guarantee the smooth and reliable use of your machine.
  • We will carry out all the design of the lifting system for you, including the drive technology, thus saving you the time-consuming work of many individual components.

Ball or trapezoidal screw

The heart of each gearbox is a precision ball or trapezoidal screw. The trapezoidal screw variant (in a good price / performance ratio) is generally chosen for more severe operating conditions. Ball screw domains are longer working cycles, high positioning accuracy and higher efficiency. The screw tube is made of aluminum (Muli 0 to 2) or made of highly resistant spheroidal graphite cast iron (Muli 3 and above), which is more stable, especially at higher temperatures. This provides a safety margin even under difficult conditions.

All models are designed for both towing and pushing forces and with position independent function. Standardized mounting material and pre-drilled flange holes allow easy installation of motor, gearbox and encoder. Synchronizing multiple transmissions is very easy.

Basic technical data

Model range of Muli gearboxes

Gearboxes are produced in versions R, N and V. In version R, the rotary movement of the screw is converted to linear movement by moving the nut. The screw is fixed by a wedge to the worm gear in the transmission. Version V with a limiting initial torque is recommended where permanent external connection of the bolt to the load is not possible. The rotation of the gearbox is transmitted to the axial movement of the screw that moves in the screw tube. The load is fixed at the end of the screw. Version N eliminates the initial torque by permanently attaching the screw to the load. In versions N and V is mounted. Stop collar to prevent the screw from turning out of the transmission. For trapezoidal screws stop collars can be ordered. Trapezoidal screws offer a limited use of the self-locking function, which depends, however, on various parameters: gear ratio, type of lubrication, friction parameters, thread pitch rate, working position and environmental influences such as. High / low temperature, vibration, etc. For this reason, the self-locking versions with ball screw and trapezoidal screw with large thread pitch are not. In these cases, the use of a suitable brake or motor with brake is recommended. Limited self-locking is assumed for the trapezoidal screw at a smaller pitch.


The transmission is lubricated at one point. Lubricating grease is applied through grease holes located in the radial axis of the housing, providing less friction and prolonging lubrication cycles and service life, especially for longer strokes. Thrust ball bearings provide a safety reserve in all versions, increasing service life. Maintenance of Thomson Neff gearboxes, whether manual or automatic, is very simple.

Load for each type

The Muli 0 to Muli 5 series gearboxes are manufactured for loads of 2.5-100 kN. In this variant we can choose between N and V versions for trapezoidal screws and N versions for ball screws. Jumbo 1 to Jumbo 5 types are designed for 150-500 kN load with the option of trapezoidal or ball screw in version R.

Gear ratio

The transmission ratio H (higher speed) reaches 1 mm of stroke per complete shaft. Speed ​​is 1 500 mm.min -1 at 1 500 m -1. The ball screw gearbox achieves a stroke of 1 071 mm.min -1 to 2 124 mm.min -1 depending on the size and pitch of the thread. At lower gearing (L), one revolution of the screw means a 0.25 mm stroke. a linear velocity of 375 mm.min-1 at 1,500 m-1. The ball screw achieves a stroke of between 312 mm.min-1 to 535 mm.min-1 depending on the size and pitch of the thread.

Tolerance and will

Axial clearance at variable load is for trapezoidal screws up to 0.4 mm (DIN 103), straightness tolerance 0.3 to 1.5 mm.m-1. For ball screws, this is up to 0.08 mm, with a straightness tolerance of 0.08 m-1 over a length of 1,000 mm. Lateral forces that may occur can be eliminated by external guidance.


EFM bronze nuts and KGF-N ball nuts have the same dimensions, so they can work with the respective adapters together. KGF-N and KGF-D flanged nuts with mounting and lubrication holes and profile seal prevent lubricant leakage and dirt from entering the screw. The degree of wear of the motion nut can be determined

  • screw jacks 840x580

Ján Plavák

Tel.: +421 37 7777 923
Mobile: +421 903 575 748
Fax: +421 37 7777 928