A jaw coupling is a kind of general purpose power transmission coupling that also can be utilized 
in movement control (servo) applications. It is designed to transmit torque (by connecting two shafts) while damping program vibrations and accommodating misalignment, which protects other elements from damage.
Jaw Couplings are one of the first and still most widely used elastomer couplings in the globe due to their inherent simplicity. Two identical hubs with 3 encounter lugs are connected through a star shaped element, sometimes known as an place or spider. The 3 piece style makes them easy to work with and well-known on applications such as for example pumps, followers, blowers and compressors.
Jaw Couplings require no lubrication and offer high reliability for light to moderate duty applications with good alignment of equipment no requirement for torsional dampening.
In regular operating conditions there is absolutely no metal to metal contact so the life of the hubs is virtually indefinite. Nevertheless, in a catastrophic failure of the element the load would still be carried by the hubs offering a amount of failure safety. Jaw couplings are resistant to essential oil, dirt, dampness and grease.
Specific element materials are available to achieve maximum performance for the functioning conditions.
The standard element material is NBR (N)-‘Synthetic Rubber’. It is highly flexible, oil resistant and the torsionally softest of the element options. It has a temperatures operating range suitable for most commercial applications and permits up to 1 1 degree misalignment capacity of the linked shafts. NBR is the most economically priced option.