EP 0350053 B1 19920610 - MULTIPLE-STAGE HYDRAULIC TELESCOPIC ACTUATOR WITH CONTROL OF THE EXTENSION OR RETRACTION OF THE TELESCOPIC PARTS IN AN IMPOSED ORDER
Title (en)
MULTIPLE-STAGE HYDRAULIC TELESCOPIC ACTUATOR WITH CONTROL OF THE EXTENSION OR RETRACTION OF THE TELESCOPIC PARTS IN AN IMPOSED ORDER
Publication
Application
Priority
DE 3823225 A 19880708
Abstract (en)
[origin: EP0350053A1] In order to improve the positional stability in the holding situation, in a multiple-stage, in particular two-stage, telescopic cylinder, which can be charged on both sides, having a control of the extension and retraction in an imposed order, the transfer of the pressure medium, fed into the cylinder pressure space (112) during extension, into the pressure space (122) of the first stage is provided by a connection line (123) in the bottom (121) of the first stage, which connection line unlocks mechanically when passing from the first stage into the final extension position, and, during retraction, the transfer of the retraction pressure medium fed in by a connection line (124), continuing via a passage (124') into the interior of the final stage, in the bottom (121) of the intermediate piston, is provided via a connection line (124") to the annular cylinder space (112'), which connection line leads from the connection line (124) in the bottom (121) of the intermediate piston to the annular cylinder space (112') and unlocks mechanically when the retracting final stage runs up against the bottom (121) of the intermediate piston. In this manner, moving over bore holes and deviations can be avoided, which require non-leak-proof seals sealing the cylinder spaces off against one another. <IMAGE>
IPC 1-7
IPC 8 full level
B66F 3/28 (2006.01); F15B 15/16 (2006.01)
CPC (source: EP)
B66F 3/28 (2013.01); F15B 15/16 (2013.01)
Designated contracting state (EPC)
DE FR GB IT NL
DOCDB simple family (publication)
EP 0350053 A1 19900110; EP 0350053 B1 19920610; DE 3823225 A1 19900111; DE 58901623 D1 19920716
DOCDB simple family (application)
EP 89112435 A 19890707; DE 3823225 A 19880708; DE 58901623 T 19890707