... of the motor into the vertical reciprocation of the sucker rod. Besides, the DLS series can, in a timely manner ... driving, commutation, speed varying, balancing, load shedding, unload protection, brake, suspension shaft, metering, and power measuring; 2. Multi-stage ... maximum load of hanging point;3. Anti-fall emergency brake and non-isometric brake linkage may realize the suspension shaft and unload ...