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.
