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R+W's Expanding Shaft Coupling EK7

R+W's Expanding Shaft Coupling EK7

Many situations which call for a motor or gearhead to be mounted into a hollow bore, such as in belt drive linear actuators, require that a stub shaft be mounted into the bore so that the motor or gearhead can be coupled to it. This method of mounting can take up a large amount of space and add unnecessary hardware to the bill of materials.

The model EK7 from R+W Coupling Technology addresses these issues with an expanding shaft. These precision couplings allow the installer to slide the male portion of the coupling into the driven bore, and with the tightening of a single screw cause the shaft to expand into the bore for a high-strength, backlash-free connection. Internal to the expanding shaft is a cone, which when tightened into the shaft, forces the outer portion of the shaft to spread and create the frictional connection to the bore.

Standard EK7 couplings are available in eight sizes with English or metric expanding shafts ranging from 10 - 80 mm (0.394 - 3.150 inch). Torques range from 9 - 2,150 Nm (79.65 - 19,027 inch-lb) though some specially made couplings can transmit up to 4,000 Nm. Three different Shore hardnesses allow the designer to select the correct amount of flexibility, vibration damping or stiffness depending on their performance requirements.

R+W's Expanding Shaft Coupling EK7
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