Global Patent Index - EP 0310022 B1

EP 0310022 B1 19920408 - HYDRAULIC TELESCOPIC DEVICE

Title (en)

HYDRAULIC TELESCOPIC DEVICE

Publication

EP 0310022 B1 19920408 (EN)

Application

EP 88115980 A 19880928

Priority

DK 515487 A 19871001

Abstract (en)

[origin: EP0310022A1] A hydraulic telescopic device is provided with several immersed pistons (2,3) positioned in a main cylinder (1) and activated by a pump (9,10) having an associated overloading valve (13) determining the maximum pressure supplied by the pump (9,10). In order to manufacture such a hydraulic telescopic device making it possible to prevent overloading of an associated lifting device a relief device is provided, which relief device is additionally designed to be inactivated automatically at the end of the stroke of the piston which is acting at the maximum pressure at which the relief device is adjusted. The telescopic device is provided with at least one relief device. The relief device comprises a connection line (28) provided in a combined cylinder head and guide member (7) and opens into a pressurized space (15) inside the cylinder (1) which is covered of the combined cylinder head and guide member (7). Moreover, the relief device comprises a relief valve (17) connected with the connection line (28) and which acts for the piston (2) in said cylinder (1). The relief valve (28) is connected with an oil tank (8) through a return line (29). Furthermore, the relief device comprises a cut-off member (19) which is activated at the end of the piston stroke in order to cut off the connection line and to inactivate the connected relief valve (17). A relief device of the above mentioned type may be arranged at each step in the hydraulic telescopic device.

IPC 1-7

B66F 3/28; F15B 15/16

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 SE

DOCDB simple family (publication)

EP 0310022 A1 19890405; EP 0310022 B1 19920408; DE 3869893 D1 19920514; DK 159289 B 19900924; DK 159289 C 19910225; DK 515487 A 19890402; DK 515487 D0 19871001

DOCDB simple family (application)

EP 88115980 A 19880928; DE 3869893 T 19880928; DK 515487 A 19871001