RACO Spring Brake Actuator Systems -
equipment and function

The rotating movement of the 24 VDC motors is transformed into straight-line movement of the thrust-tension rod through the ball screw. This transfers the motor's kinetic energy to a specially selected spring brake package when the vehicle brake is released.

The spring brake is relaxed by a brake command or power failure and the thrust-tension rod impinges the brake shoes with the specified braking force. The motor runs through the ball screw that does not have self-locking.

A built-in force measurement system tracks the force exerted over the thrust-tension rod to allow graduated to quasi continuous soft braking. If there is a power failure, the brake is released and the motor runs down gradually with the generator brake.

The braking control mechanism and our patented braking force electronic control system regulates the braking force sensitively without braking jerks and depending upon the desired value specified. It thus compensates for brake shoe wear and tear.

Various types of spring brake actuator systems allow the braking energy to be transferred to the brake through the thrust rod (braking running out) or the tension rod (braking running in).