Patent ID: 7600612
Filing Date: 2009-10-13
Classification: B66F,F15B

Abstract:
1. An industrial vehicle comprising: a lifting device; a main hydraulic system to control an operation of the lifting device; a first pump motor configured to provide hydraulic flow to the lifting device, wherein the first pump motor provides exclusive hydraulic fluid to the lifting device; a plurality of hydraulic devices other than the lifting device; a second hydraulic system to control an operation of the plurality of hydraulic devices, wherein the second hydraulic system is fluidly coupled to the main hydraulic system; a second pump motor configured to provide hydraulic flow to the second hydraulic system when one or more of the plurality of hydraulic devices are actuated, wherein the second pump motor provides exclusive hydraulic fluid to the plurality of hydraulic devices, and wherein the lifting device is simultaneously raised or lowered while the plurality of hydraulic devices are actuated; and a third hydraulic system that is fluidly coupled to the second hydraulic system, wherein a load sensing circuit controls hydraulic flow provided from the second pump motor between the second and third hydraulic systems when the plurality of hydraulic devices are actuated, and wherein when none of the plurality of hydraulic devices are actuated all the combined hydraulic flow from both the first and second pump motors is provided exclusively to the lifting device.