초록 ▼

A hydraulic system (20) for controlling the seed/fertilizer supply system (10) and the down pressure on a plurality of individual row units (12). A secondary supply arrangement (60) interconnects a first control circuit (26) of supply system (10) with a second control circuit (28), when the row unit

A hydraulic system (20) for controlling the seed/fertilizer supply system (10) and the down pressure on a plurality of individual row units (12). A secondary supply arrangement (60) interconnects a first control circuit (26) of supply system (10) with a second control circuit (28), when the row units (12) are in a float mode, to provide pressurized fluid for the down force on the row units (12) during operation.

대표청구항 ▼

1. A hydraulic system for a work implement (8) towed by a work machine (6) comprising:a source of pressurized fluid (22); a first control valve (30) being connected to said source of pressurized fluid (22); a second control valve (40) being connected to said source of pressurized fluid (22); a fluid

1. A hydraulic system for a work implement (8) towed by a work machine (6) comprising:a source of pressurized fluid (22); a first control valve (30) being connected to said source of pressurized fluid (22); a second control valve (40) being connected to said source of pressurized fluid (22); a fluid motor (32) being connected to said first control valve (30) by a supply conduit (34) and a return conduit (36); an actuator (42) having a down force end (42a) being connected to said second control valve (40) by a conduit (44) and a lift end (42b) being connected to said second control valve (40) by a conduit (46); a pressure responsive valve (62) disposed between the supply conduit (34) and the down force end (42a) of said actuator (42) and movable between a first position communicating the supply conduit (34) with the down force end (42a) of said actuator (42) and a second position blocking the supply conduit (34) from the down force end of said actuator (42); and said pressure responsive valve (62) having first and second ends (68,70), a spring (72) disposed at the first end (68) biasing the pressure responsive valve (62) to the first position and a pilot line (74) communicating the lift end (42b) of the actuator (42) with the second end (70).