The invention relates to the technical field of hydraulic systems of
engineering machinery, and discloses a compact load-sensitive
proportional valve of an integrated hydraulic lock, which comprises an oil inlet body and a reversing body which are fixedly connected through a bolt. A main valve element is installed in the middle of the oil inlet body in a sliding mode, a pressure adjusting plug screw, a flow dividing spring, an unloading valve
assembly and other components are arranged, the opening pressure can be adjusted, and
overpressure unloading is achieved. A hydraulic lock
assembly and a pressure compensation valve element are arranged in the reversing body and are designed in a coaxial nesting mode, and a valve element of the hydraulic lock
assembly is of a double-conical-
face structure. A control oil way is communicated with a main valve element displacement cavity to achieve linkage unlocking, and a load
pressure feedback channel is isolated from a
control channel through an independent spiral oil channel. A micro filter is arranged at an inlet of the hydraulic lock control oil duct and used for preventing
pollution. The invention has the advantages of compact structure, strong anti-
pollution capability and fast dynamic response, can realize the accurate matching of a pump valve
system and load pressure flow, and is suitable for the control of actuating mechanisms of
engineering machinery such as tractors, cranes and the like.