US 6,782,910 B2Granted

Multi-function hydraulic valve assembly

AssigneeLift Technologies, Inc.

InventorsLuciano Mondani, Mark Dodd

Life of this patent

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Abstract

A hydraulic valve assembly for selectably delivering hydraulic fluid from a supply of hydraulic fluid to one of a first hydraulic operator and a second hydraulic operator is disclosed. The assembly includes first and second supply ports which communicate with the supply and four operator ports. First and third ports communicate with the first hydraulic operator. Second and fourth ports communicate with the fourth hydraulic operator. First and second chambers are provided. The first chamber communicates with the first supply port and first and second operator ports. The second chamber communicates with the second supply port and third and fourth operator ports. Two selection valves operating in unison are each located in each chamber. The selection valves operate between a first position at a first hydraulic fluid pressure and a second position at a second hydraulic fluid pressure. In a first position, the valves permit fluid communication of the first and second supply ports with the first and third operator ports, respectively. In a second position, the valves permit fluid communication with the second and fourth operator ports.

Claims29

Dependent claims

A hydraulic valve assembly for selectably delivering hydraulic fluid from a supply of hydraulic fluid to one of a first hydraulic operator and a second hydraulic operator, said assembly comprising:

a) a valve block defining:
i) a first supply port adapted for fluid communication with said supply;
ii) a second supply port adapted for fluid communication with said supply;
iii) a first operator port adapted for fluid communication with said first hydraulic operator;
iv) a second operator port adapted for fluid communication with said second hydraulic operator;
v) a third operator port adapted for fluid communication with said first hydraulic operator;
vi) a fourth operator port adapted for fluid communication with said second hydraulic operator;
vii) a first chamber, said first chamber being in fluid communication with said first supply port, said first operator port, and said second operator port;
viii) a second chamber, said second chamber being in fluid communication with said second supply port, said third operator port and said fourth operator port;
b) a first selection valve located in said first chamber and a second selection valve located in said second chamber, said first and second selection valves being adapted to move in unison, said first and second selection valves operable between a first position when said hydraulic fluid is at a first pressure and a second position when said hydraulic fluid is at a second pressure, where in said first position, said first selection valve permits fluid communication between said first supply port and said first operator port, and said second selection valve permits fluid communication between said second supply port and said third operator port, where, in said second position, said first selection valve permits fluid communication between said first supply port and said second operator port, and said second selection valve permits fluid communication between said second supply port and said fourth operator port;
wherein said first pressure is lower than said second pressure.

8 more elements

A hydraulic valve assembly for delivering hydraulic fluid from a supply of hydraulic fluid to one of a first hydraulic operator and a second hydraulic operator, said first hydraulic operator being a fork positioner for a lift truck and said second hydraulic operator being a side shifter for a lift truck, said assembly comprising:

a) a valve block defining:
i) a supply port adapted for fluid communication with said supply;
ii) a first operator port adapted for fluid communication with said first hydraulic operator;
iii) a second operator port adapted for fluid communication with said second hydraulic operator;
iv) a chamber, said chamber being in fluid communication with said supply port, said first operator port, and said second operator port;
b) a selection valve located in said chamber, said selection valve operable between a first position when said hydraulic fluid is at a first pressure and a second position when said hydraulic fluid is at said second pressure, where in said first position, said selection valve permits fluid communication between said supply port and said first operator port, where in said second position, said first selection valve permits fluid communication between said supply port and said second operator port;
wherein said first pressure is lower than said second pressure.

4 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/120,789Filed 12 Apr 2002 · us provisional application
Priority: 1 Mar 2002
Published: US 2003/0164189 A14 Sep 2003
Granted: 31 Aug 2004
Term ends: Not estimatedThe source records don’t support an estimate.

Classification11 codes

B66F 9/148
Whole unit including fork support moves relative to mast: whole unit including fork support moves sideways
B66F 9/143
Movements of forks either individually or relative to each other: movements of forks relative to each other - symmetric
B66F 9/22
Means for actuating or controlling masts, platforms, or forks: hydraulic devices or systems
F15B 11/20
With two or more servomotors: controlling several interacting or sequentially-operating members