EP 0581270 A3 19940831 -
Publication
Application
Priority
DE 4225032 A 19920729
Abstract (en)
[origin: EP0581270A2] The telescopic system consisting of several plunger-type cylinders (1, 2, 3) is intended in particular for the actuation of a jib in cranes or the like. The plunger-type cylinders (1, 2, 3) are arranged to be longitudinally displaceable relative to one another and are guided one inside the other like a piston/cylinder arrangement in such a way as to be extendable by pressurising with a hydraulic medium. Each of the longitudinally displaceable plunger-type cylinders (1, 2, 3) is closed by a plunger head (5) at its rear end face in the extension direction. In this arrangement, an overflow passage (6) for the hydraulic medium is provided in the plunger head (5), which overflow passage (6) extends axially between its two sides and can be closed by a check valve (7), and an actuating member for the check valve (7) is provided in the area of the plunger head (5). The check valve (7) is opened only when the plunger-type cylinders (2, 3) are fully extended. Provided in the cylinder space of each of the longitudinally displaceable plunger-type cylinders (2, 3) is a locking ring (8) which can be adjusted axially by the plunger head (5) of the next plunger-type cylinder (3) arranged in the cylinder space against the force of a spring (9) towards the plunger head (5) and actuates at least one radially adjustable locking member (10). In the position of the locking ring (8) remote from the plunger head (5), the locking member (10) locks the displaceability of this plunger-type cylinder (3, 2) relative to the plunger-type cylinder (2, 1) enclosing it. The retraction of the individual plunger-type cylinders is achieved by the application of an external force to a rope held permanently tensioned by means of a travel motor. <IMAGE>
IPC 1-7
IPC 8 full level
B66C 23/70 (2006.01); F15B 15/14 (2006.01); F15B 15/16 (2006.01); F15B 15/26 (2006.01)
CPC (source: EP)
B66C 23/701 (2013.01); F15B 15/1476 (2013.01); F15B 15/16 (2013.01); F15B 15/261 (2013.01)
Citation (search report)
- [A] DE 3021633 A1 19811217 - SCHUETT FRIEDRICH [DE]
- [A] DE 2900015 A1 19800710 - BENTELER WERKE AG
- [A] GB 2206929 A 19890118 - OP PAGLIERO S P A
- [A] DE 1240743 B 19670518 - TOUSSAINT & HESS GMBH
- [A] DE 3835945 C1 19900201
Designated contracting state (EPC)
AT BE CH DE DK ES FR GB IT LI LU MC NL PT SE
DOCDB simple family (publication)
EP 0581270 A2 19940202; EP 0581270 A3 19940831; EP 0581270 B1 19980520; AT E166434 T1 19980615; DE 4225032 A1 19940203; DE 59308566 D1 19980625
DOCDB simple family (application)
EP 93112071 A 19930728; AT 93112071 T 19930728; DE 4225032 A 19920729; DE 59308566 T 19930728