Lowering valve for controlling the descending speed of a hydraulically operated lift

摘要

A lowering valve (1) has a closing body (6) which in the closed position shuts off a pressure chamber (3) from a discharge chamber (5), which pressure chamber (3) is connected to the hydraulic cylinder (9) of the lift (11). The closing body (6) is subdivided into a closing part (32) for shutting off the two chambers (3 and 5) and into a metering part (33) which is provided with discharge openings (51) for connecting the two chambers (3 and 5). The discharge openings (51) are opened in a controlled manner by a control edge (57). The metering part (33) is acted upon by the pressure in a regulating chamber (44) against the force of a compensating spring (56) for closing the discharge openings (51) in a controlled manner and can be extended relative to the closing part (32). The operating pressure present in the pressure chamber (3) is fed to the regulating chamber (44) via a pressure-sensing opening (46).