Hydraulic brake valve device for use in wheel or chain excavators for controlling discharge side of internal combustion engine, has pre-opening connecting side of load with container and switchable between locking and flow positions

摘要

The device (2a) has pre-openings (25a, 25b) connecting discharge sides of a hydraulic load (3) with a container (12) and switchable between a locking position and a flow position, where the device is arranged in drain lines (11a, 11b) that attaches the discharge sides of the load with the container. The locking position closes the drain lines, and the flow position opens the drain lines, where the device operates in a thrust phase of the load based on a control signal toward the flow position and pressurizes in a brake phase of the load of a spring unit toward the locking position.