| 摘要 |
A hydraulic valve of the type having a plurality of flow directing spools and valve bodies, normally disposed in a stack, or sectional control valve assembly, with registering like passageways on adjacent valve bodies in fluid communication. An open center pilot arrangement is provided to initially control the pressure of fluid supplied to an output passageway of an individual valve when its spool is moved to a position to supply fluid to a load connected thereto. A balanced flow control is disposed in each valve body between an inlet passageway and an outlet passageway and to a loop and an output passageway. The flow control is operative in response to the pressure in one of the output passageways of the valve body to control the proportionate flow of the fluid to the output passageway and the outlet passageway of the valve body. A number of individual valves may be operated in a stack in such a manner that an "upstream" valve will have "priority". Under such conditions two or more valves may be operative simultaneously as long as the total fluid demanded does not exceed the source of supply. Should the demand exceed the source of supply, the valves will operate in sequence.
|
