Elevator – industrial lift truck – or stationary lift for vehicle – Industrial lift truck or required component thereof – Having extensible vertical guide for load support
Reexamination Certificate
2007-07-10
2007-07-10
Crawford, Gene O. (Department: 3654)
Elevator, industrial lift truck, or stationary lift for vehicle
Industrial lift truck or required component thereof
Having extensible vertical guide for load support
C187S226000, C187S234000, C187S274000, C187S275000, C187S346000, C254S423000, C254S08900R, C254S0930VA, C091S525000, C091S533000, C060S422000, C060S484000
Reexamination Certificate
active
11100654
ABSTRACT:
A multistage mast assembly for use on a lift truck and method of operation for staging first and second mast sections of the multistage mast assembly. Each mast section has a retracted position and an extended position. The apparatus includes a mast staging hydraulic circuit which diverts hydraulic fluid from the second mast section actuator to the first mast section actuator using a multi-position valve having an open position and a restricted flow position. In the restricted flow position, hydraulic pressure in a hydraulic line supplying the second mast section increases to divert hydraulic fluid to the first mast section actuator before the second mast section reaches its extended position.
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PCT International Search Report dated Sep. 6, 2005.
Crawford Gene O.
Kruer Stefan
Quarles & Brady LLP
The Raymond Corporation
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