HYDRAULIC LIFTING-LOWERING-SYSTEM FOR A WORKING TABLE, A COUCH OR LYING FURNITURE OR ANOTHER HEAVY OBJECT

摘要

In a hydraulic lifting-lowering-system for a working table, a couch or lyingfurniture or another heavy object, the height level or position it isfrequently desiredto adjust or change, said system comprising a predetermined amount ofhydraulicfluid, a hydraulic fluid accumulator (5), the fluid pressure of which on thehydraulicfluid side is adjustable, a single acting hydraulic cylinder (1, 6, 7, 10, 11,12, 17) withtwo end caps (10, 12), a piston pressure chamber (17) and a piston rod (6)which viaa piston rod sealing ring (11) extends sealingly out through the one end cap(10) ofthe cylinder, where the piston pressure chamber (17) is pressure fluidconnected tothe hydraulic fluid side of the accumulator (5), said system including thecombinationthat the hydraulic cylinder (1, 6, 7, 10, 11, 12, 17) is of the plunger pistontype,and that the cylindric tube (1) of the hydraulic cylinder is slideably andtelescopicallymounted in a cylindrical guiding tube (2), which surrounds the piston rod inits entirelength and is rigidly secured to the one end of the piston rod via a crossplate (3A) orsimilar construction part. Thus, a simple and stable and reliable system isachievedwithout the need for crank handles, and by which new system the force appliedfromthe plunger piston rod will be essentially constant in all positions of thepiston rod ata given load, seeing that the operational manual force necessary for heightadjustmentof the heavy object becomes low.