Hydraulic control valve system for controlling hydraulic driving system in e.g. mechanical loading application, has motor connected to valve stem, where ratio of diameter of virtual circle and height of coils is higher than specific value

摘要

The system has hydraulic control valve segments (4) comprising a removable valve stem (22) to open and close hydraulic channels (12, 14) at variable degrees according to a position of the stem. Actuators (8) for the segments include an electric motor i.e. brushless direct current motor, connected to the stem by a coupling mechanism (33). The motor comprises a rotor (36) and a stator (32). Ratio of average diameter of a virtual circle across median points of coils (42) of the stator and total height of the coils along direction parallel to a rotation axis of the rotor is greater than 1.6.