FLUID OPERATED SYSTEM CONTROL

摘要

Fluid Operated System Control Controlling arrangements for controlling the amount of fluid flow deliverable from a pump to a work system tend to be complex, waste substantial amounts of energy, are costly, and operate inefficiently due to the inability to provide the proper amount of fluid flow. A control having a primary work system, a secondary work system, a first fluid flow generating system, and a second fluid flow generating system is provided. A control signal delivering device is provided to deliver a control signal having a magnitude responsive to a relative location of a control valve between a first and second position of a control valve. A control signal receiving device receives the control signal and separately controls the flow rate deliverable from the first and second flow generating system in response to the magnitude of the control signal received. The control signal receiving device has a set point value which is representative of a preselected magnitude of the received control signal The second fluid flow generating system is controlled to deliver fluid only in response to the magnitude of the received control signal having a value greater than the set point and at a substantially constant preselected deliverable flow rate. The first flow generating system is controlled to deliver fluid at a rate responsive to the magnitude of the received control signal and, during periods at which the received control signal has a value greater than the set point, reduces the fluid flow deliverability rate of the first flow generating system, an amount substantially equal to the flow rate being delivered by the second flow generating system. Therefore, the problems of cost, inefficiency, controllability and the like are eliminated. The control is particularly suited for use in the fluid operated system of a material handling vehicle.