Spring applied, power-off brakes (also known as fail-safe brakes) are used in applications that require the axis to stay in position when power is removed or lost. A common use case for power-off brakes is with a vertical application where the axis will fall due to gravity if bus power is removed.
Spring-applied brakes use a metal spring to apply a braking force to the brake output shaft when 24VDC is not supplied to the brake. When 24VDC is supplied to the brake, the brake coil is energized and the brake spring is compressed. Applying 24VDC to the brake allows the brake output shaft to spin when driven by a motor.
These spring-applied, power-off brakes have a standard NEMA input/output mounting flange. The NEMA23 brake accepts a NEMA23 3/8” diameter input shaft and provides a 3/8” diameter output shaft. The NEMA34 brake accepts a 1/2” diameter input shaft and provides a 1/2” diameter output shaft. A motor housing is attached to a brake housing using 4 screws and threaded holes (in the brake housing). The motor shaft is attached to the brake shaft using an integrated shaft clamp.
The brakes are manufactured by Newstart Motion, a precision motion component manufacturer. Teknic has recommended Newstart brakes (and other products) for a number of years, and they have proven to be robust and reliable. Now these brakes are available direct from Teknic and come with a standard 3 year warranty, 90-day money-back evaluation period, and a 3 day lead time when ordering on Teknic’s website.