HYDRAULIC DRIVE Russian patent published in 1995 - IPC

FIELD: hydraulics. SUBSTANCE: hydraulic drive has differential force cylinder, distributor 2, and relief valve 3. Valve 3 has housing 8 and slide 10 with rod 11 spring-loaded from both sides with springs 12 and 13. Slide space 14 and under-piston space 15 are defined inside the housing, the spaces being in communication with the above-piston and under-piston spaces of the cylinder respectively. The areas of spaces 14 and 15 are proportional to the areas of spaces 4 and 5 of the cylinder. Ring recesses 18-20 are made in the housing. Two passageways of opposite directions are made in the slide. The passageways have longitudinal parts 21 and radial parts 22. EFFECT: improved design. 2 cl, 1 dwg