Improvements in control systems for hydraulic spool valves

Kontrollsystem für hydraulische Zylinderschieber

Systèmes de contrôle pour tiroir cylindrique hydraulique


The system includes an actuation device having a d.c. electric motor (10, 20) and a high-ratio gearbox (11). The output of the gearbox connects with the spool (13) ofthe valve through a segmented rack and pitman pin or a rack and pinion arrangement (12). A control circuit for the electric motor includes position feed-back (17) to permit accurate positioning of the spool. Further, spring means are included to bias the spool to its neutral position in the absence of a control signal or on occurrence of a fail condition. A suitable control device for the control system is also disclosed, the device having a command leve with a pair of catering springs. Detent means for the lever is also shown.




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Patent Citations (1)

    Publication numberPublication dateAssigneeTitle
    GB-2085129-AApril 21, 1982Kontak Mfg Co LtdValve actuator

NO-Patent Citations (0)


Cited By (3)

    Publication numberPublication dateAssigneeTitle
    EP-0691252-A1January 10, 1996Thomson-CsfDispositif de commande d'un tiroir hydraulique
    FR-2721413-A1December 22, 1995Thomson CsfDispositif de commande d'un tiroir hydraulique.
    US-5611518-AMarch 18, 1997Thomson-CsfControl device for a hydraulic slide valve