PERFORMANCE WITH ECONOMY FROM CURVED JAW SHAFT COUPLINGS
CURVED JAW COUPLINGS SUIT A WIDE VARIETY OF APPLICATIONS
Curved jaw types of flexible shaft coupling consist of two hubs and a central polyurethane element with curved faces. The basic design is available for simple low-cost machine applications, but variants offer higher performance even suiting reversing servo motor drives. Techdrives offer curved jaw couplings in simple up to high performance designs suiting shafts from 3 to 90mm diameter.
The curved shape of the polyurethane elements ensure that surface loads are spread and always in compression. This leads to long service life and aids flexibility giving a typical misalignment capacity of 1 to 1.5 degrees. Coupling characteristics can be modified by changing the hardness of the element. Techdrives offer a ‘yellow’ softer element with hardness of 92 Shore A. This results in medium levels of torque and softness. Interchangeable is a ‘red’ element that is harder at 98 Shore A resulting in about 40% more rated torque and double the stiffness.
The hubs for basic couplings have cast jaws to minimise costs. They are supplied in either aluminum or cast iron and fixed to shafts with a keyway and grubscrew. Higher performance versions have aluminum hubs that are split with a side clamping bolt to achieve a clamp connection to the shaft without a keyway. Note that the transmittable torque may be limited by the shaft diameter. These hubs have fully machined jaws resulting in zero backlash. They are proven as a good low-cost solution for reversing servo drives.
Curved jaw couplings are well established in Europe and in many cases the performance is practically interchangeable from different suppliers, and sometimes even the individual component parts are interchangeable too. Techdrives offers a range from low-cost basic models to zero-backlash high performance. The availability of elements with different hardness gives additional performance options.