The series motors are designed for operating with electromagnetically operated brakes. In the operating principle these brakes belong to multidisk brakes actuated by short-stroke electromagnets.
Braking results from friction between the rotating disks lined with a friction material and the stationary steel disks. The rotating disks are fitted on bushes keyed to the motor shaft. The stationary disks are fitted on pins secured in the frame.
The electromagnetic system of the brake consists of the two annular cores made of wound steel ribbon, and six coils uniformly spaced around the core circumference. One of the cores is stationary and is welded to the frame. The other core is fitted on the same pins as the stationary disks and is capable of moving in the longitudinal direction. Mounted between the frame and the movable core is the main braking spring.
The spring force is applied through the movable core to the stationary disks and through the friction surfaces to the rotating disks.
The brakes have provisions for manual unbraking, for adjusting the breaking effort through adjustment of the spring force and for adjusting the electromagnet travel to bring it to a normal value as the friction surfaces wear off. In the course of braking the brake absorbs the energy of the rotating masses.
The entire braking energy is distributed between the mechanical brake, the motor and the load.
