Pre- and post- compensational valve arrangement

摘要

Hydraulic valve arrangements may be assembled to provide pre-compensation or post-compensation using the same chassis body. A first type of main spool is disposed in a main passage and a first type of pressure compensator spool is disposed in a compensator passage to provide pressure pre-compensation. The first type of pressure compensator spool connects to a first pilot location and not to a second pilot location. A second type of main spool is disposed in the main passage and a second type of pressure compensator spool is disposed in the compensator passage to provide pressure post-compensation. The second type of pressure compensator spool connects to the second pilot location and not to the first pilot location. The valve arrangement may be switched from pre-compensation to post-compensation (or vice versa) by switching out the main spool and pressure compensator spool without making any other changes to the chassis body.

主权项

1. A hydraulic load sense flow control system that interfaces with a pump of a valve system, the hydraulic load sense flow control system including at least one valve section, each valve section comprising:
a valve body defining a main spool bore, a compensation spool bore, at least one inlet port, at least one return port, and at least one working port, the inlet port being configured to receive pump flow, the valve body including a drive circuit for directing pump flow from the inlet port to the working port, the valve body also defining first and second separate load sense pilot pressure input locations at the compensation spool bore, the valve body defining a load sense circuit for: a) determining a highest load sense pressure of the valve system based on a localized working pressure from each valve section of the valve system; b) communicating the highest load sense pressure to the second load sense pilot pressure input location; and c) communicating the localized working pressure of the valve section to the first load sense pilot pressure input location; a directional flow control spool that mounts in the main spool bore for controlling the pump flow provided to the working port by the drive circuit; and a pressure compensation spool that mounts in the compensation spool bore for providing pressure compensation to the pump flow directed through the drive circuit, the pressure compensation spool having a first pilot surface that is in fluid communication with one of the first and second load sense pilot pressure input locations and that is blocked from fluid communication with the other of the first and second load sense pilot pressure input locations.