DEVICE FOR WORK IN ROWS OF PERENNIAL PLANTS Russian patent published in 1994 - IPC

FIELD: agricultural engineering. SUBSTANCE: for better cultivation of trunk zone and lower damage to plants the device comprises frame 1 with articulated hydraulic cylinder 2 controlled by two-arm feeler 3 pressed by spring 4 against adjustable stop 5, and hydraulic drive 6 and 7 of cock-type hydraulic control valve 8 mounted on shank of revolving sweep 9. Hydraulic control valve 8 is comprised of body with spool valve inside. Discharge and pressure ports in body are displaced from its axis of symmetry. At the side of working lines the body has hollows in the form of segment-shaped slot whose area is equal to the area of pressure hydraulic line 18. Spool valve at the pressure and discharge spaces has bands forming, together with displaced body ports, small and large gaps. Pressure and discharge lines communicate through two longitudinal holes while at the side of pressure line, through two holes arranged transversely to longitudinal ones. The area of each transverse hole of pressure line is equal to half the area of hole in pressure line 18. EFFECT: improved design. 2 cl, 3 dwg