Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
77 words
A method of actuating hydraulic consumers, each hydraulic consumer being connected to a hydraulic pressure line by a respective hydraulic directional control valve, wherein each of the hydraulic directional control valves is actuatable to connect the associated hydraulic consumer to the hydraulic pressure line by a respective electro-hydraulic pre-control valve, and wherein the pre-control valves are associated with electro-hydraulic directional control valve means in such a manner that the pre-control valves operate against substantially no hydraulic pressure.
Claim 2
Independent Claim
77 words
A method of actuating hydraulic consumers, each hydraulic consumer being connected to a hydraulic pressure line by a respective hydraulic directional control valve, wherein each of the hydraulic directional control valves is actuatable to connect the associated hydraulic consumer to the hydraulic pressure line by a respective electro-hydraulic pre-control valve, and wherein the pre-control valves are associated with electro-hydraulic directional control valve means in such a manner that the pre-control valves operate against substantially no hydraulic pressure.
Claim 3
Dependent Claim
24 words
A method according to claim 1, wherein actuation of the electro-hydraulic directional control valve means causes any previously-actuated pre-control valve to be hydraulically locked.
Claim 4
Dependent Claim
139 words
An arrangement for controlling the actuation of hydraulic consumers, the hydraulic consumers being connected to a hydraulic pressure line, the control arrangement comprising a respective hydraulic directional control valve associated with each of the hydraulic consumers, a respective electro-hydraulic pre-control valve associated with each of the hydraulic directional control valves, and electro-hydraulic directional control valve means associated with the pre-control valves, each of the hydraulic consumers being connected to the hydraulic pressure line via the associated hydraulic directional control valve, wherein each hydraulic directional control valve is actuated by a control line leading from the output side of the associated pre-control valve, and wherein the input sides of the pre-control valves are connected directly to a hydraulic return line and indirectly, via the electro-hydraulic directional control valve means, to the hydraulic return line or to a hydraulic control line.
Claim 5
Dependent Claim
139 words
An arrangement for controlling the actuation of hydraulic consumers, the hydraulic consumers being connected to a hydraulic pressure line, the control arrangement comprising a respective hydraulic directional control valve associated with each of the hydraulic consumers, a respective electro-hydraulic pre-control valve associated with each of the hydraulic directional control valves, and electro-hydraulic directional control valve means associated with the pre-control valves, each of the hydraulic consumers being connected to the hydraulic pressure line via the associated hydraulic directional control valve, wherein each hydraulic directional control valve is actuated by a control line leading from the output side of the associated pre-control valve, and wherein the input sides of the pre-control valves are connected directly to a hydraulic return line and indirectly, via the electro-hydraulic directional control valve means, to the hydraulic return line or to a hydraulic control line.
Claim 6
Dependent Claim
27 words
An arrangement according to claim 3, further comprising a control box for actuating the pre-control valves and the electro-hydraulic directional control valve means via electric control leads.
Claim 7
Dependent Claim
28 words
An arrangement according to claim 3, wherein, in a first operating position, the input sides of the pre-control valves are connected to the return line via hydraulic lines.
Claim 8
Dependent Claim
24 words
An arrangement according to claim 3, wherein the pre-control valves are electro-hydraulic seating valves having electro-magnets whose current consumption is less than 50 milliamps.
Claim 9
Dependent Claim
21 words
An arrangement according to claim 6, wherein the current consumption of the electro-magnets of the pre-control valves is about 10 milliamps.
Claim 10
Dependent Claim
47 words
An arrangement according to claim 3, wherein each of the pre-control valves includes a stepped valve stem slidably mounted within a valve sleeve, first and second valve seats, and a valve piston constituting a double valve closure member, the valve piston being formed as a double cone.
Claim 11
Dependent Claim
46 words
An arrangement according to claim 8, wherein the pressure-loaded annular area, of external diameter D2, formed by the valve sleeve of each pre-control valve, is larger than the annular area of the associated valve piston, of external diameter D1, effective on the associated first valve seat.
Claim 12
Dependent Claim
45 words
An arrangement according to claim 8, wherein the annular area of the valve piston of each pre-control valve, of external diameter D3, effective on the associated second valve seat is larger than the annular area of external diameter D2 defined by the associated valve sleeve.
Claim 13
Dependent Claim
61 words
An arrangement according to claim 8, wherein each pre-control valve has a valve antechamber connected via a connection bore to a hydraulic line leading to the electro-hydraulic directional control valve means, a valve chamber connected via a connection bore to the associated control line, and a spring chamber connected via a connection bore and a hydraulic line to the return line.
Claim 14
Dependent Claim
20 words
An arrangement according to claim 3, wherein each of the hydraulic consumers is a working chamber of a hydraulic ram.
Claim 15
Dependent Claim
44 words
An arrangement according to claim 12, wherein a plurality of electro-hydraulic directional control valves constitute the electro-hydraulic directional control valve means, each electro-hydraulic directional control valve being associated with the two pre-control valves associated with the two working chambers of a respective hydraulic ram.