... (L)-100-M(B/I/M)-J-C)JW series spiral elevator features:1. JWM type ( ... economy, compact structure, simple operation, maintenance is convenient. 2, low speed, low frequency: mainly used in large load ... self-locking function failure, then please plus brake.2. JWB type (ordinary ball screw type)JWB type ... small drive source, can produce very big impetus. 2 and fast pace: compared with trapezoid screw speed ...