A Spring-Powered Brake from Nexen

Oct. 19, 2009
A spring-powered brake from Nexen.

 The RB Series of guide-rail brakes from Nexen Group Inc., Vadnais Heights, Minn. (www.nexengroup.com), is powered by pair of springs nested within each other to hold loads precisely in place on guide rails. The device works with most rails, including: NSK, SKF, INA, THK, IKO, Hiwin, and Star. The brake clamps directly onto the center of the rail, providing positive braking and holding in all axes. The spring-engaged, air-release brakes weigh 1.86 lb and exert 225 lb of holding force.

The springs’ stopping power is magnified and transferred into the rail via a driving wedge. Four roller bearings support and stabilize the wedge, letting it move freely from an engaged to a disengaged position. To release the brake, several stacked pistons use 80 psi to provide enough force to overcome the springs. The stacked configuration lets the brake stay within the profile of a standard ball carriage.

The facing holds the rail precisely without damage, and is durable enough to handle several emergency stops without significant wear. Return springs let the facing disengage the rail when air is applied. And because these springs are on the ends of the brake, they ensure the facing will not rock and contact the rail during moves.

Edited by Stephen J. Mraz

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