Drum brakes with electrohydraulic thrustor of ZE or EB type and with the electromagnetic thrustor of DZEMz type are adjusted to cooperation with brake drums on their external surface. The braking torque is created by the spring inbuilt in the thrustor body (AHH, AHG) or in the compound lever (AHH series 300, AHM), which through the compound lever causes pressing down the brake shoe with friction lining to the friction surface of the brake drum (with the exception of holding brake AHT).
Brakes with electrohydraulic thrustor
Turning the voltage supplying the thrustor on starts the motor and the pump forcing the oil under the piston of the release , which causes that the piston moves up and the brake is thrustord (with the exception of the holding brake). Turning off the power causes that the piston moves down (under the influence of the spring in the thrustor) and the brake is applied.
The value of the braking torque can be adjusted through the change of brake position on appropriate lever.
The speed of falling or raising the piston can be adjusted through the use of the valve delaying falling or raising of the piston.
Brakes with electromagnetic thrustor – AHM
Turning the voltage supplying the thrustor on starts the electromagnet of the thrustor, which pulls the piston up causing through the compound lever the brake release.
The value of the braking torque can be adjusted through the change of braking spring deflection. Brakes with electromagnetic thrustor can be produced in the type intended for operation in the areas with the danger of explosion.