Fail safe brake for vertical and slant axes in machine tools

Characteristic features:

•Easy assembly between servo motor and bell housing

•Completely enclosed at the outer diameter

•Complete with zero backlash coupling

•Insulation class F and designed for 100 % ED

Concept

The ROBA-stop®-alpha is a fail safe brake that is mounted between the servo motor and a bell housing. The gear hub of the brake is combined with a smartflex®zero backlash steel bellows coupling. Frictionally locked clamping rings assure backlash-free torque transmission between servo motor and ball screw.

Two sizes of ROBA-stop®-alpha cover Fanuc servo motors from sizes alpha 6 to 30, or others with same frame size. The brake is supplied with connecting plug and socket. The standard coil voltage is 90 VDC. Other voltages are available on request.

The brake can easily be implemented into exisiting designs. Different coupling sizes and an adapter kit assure that the available distance between shafts will be met.

Design

Installation into existing designs between servo motors is simple and possible without modifications. By modifying the bell housing the length of the drive and, therefore, the machine height may be optimised.

Function

The ROBA-stop®-alpha is a spring loaded electromagnetic fail safe brake.

Spring loaded:

In a de-energised condition helical springs press against the armature disk. The rotor is held stationary between the armature disk and flange plate. The shaft is braked via the gear hub.

Electromagnetic:

When power is switched on, a magnetic field is built up. The armature disk is attracted to the coil carrier against the spring pressure. The brake is released and the shaft is then able to rotate freely.

Safety brake:

Safe and reliable braking action when the current has been switched off, in case of "emergency OFF", or through power failure.