Choice Torque

Tuesday 10th March 2009
Choice Torque

Abssac is well known for supplying the original helical beam flexible shaft coupling. The product has a reputation for reliability and antibacklash torque transmission, but you may not be aware of the additional advantages the product can offer to power transmission applications. When parameters such as torque and angular shaft misalignment are outside of the normal, the helical beam product can be a useful ally. 

The unique advantages lie in the products capability to change the actual helical beam configuration, or “ flexure” as it is often termed. In affect, the flexure part of the shaft coupling can be tuned to suit individual application requirements.

For example, by varying the thickness of the flexure, the coupling can accommodate increasing amounts of torque and radial loads. The design engineer can specify the torsional stiffness and compression spring rates independent of other factors such as angular offset and parallelism acceptance. When the inside diameter of the flexure changes, so does the torque capacity, torsional stiffness and axial spring rates, without restricting your choice of bore sizes. When the number of rotations of coils is changed, the torque capacity remains unaffected, but all the other characteristics change. Then the option to use multiple start coils, such a double and triple start coil configurations, can ultimately provide higher torsional stiffness to the part.

An additional advantage is the fact that high strength materials such as 17-4PH CRES steels can be used as well as 7075-T6 Aluminium. Factors such as elasticity, fatigue, corrosion resistance, mass, magnetic permeability, operating temperature are all affected by the material choice.

The performance and attachments available to the engineer are therefore endless but ultimately allows a very bespoke shaft coupling to be supplied. However, the machine tools that manufacture the standard shaft couplings can be utilised for these bespoke designs which ensures cost efficiency.

The next time you are reviewing your rotary power transmission designs it might be worth considering the Abssac helical beam shaft coupling.


For more information follow this link : Specialist flexures

ABSSAC Limited

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