inner coating of lampengefu00e4ssen as entladungsgefu00e4ssen of gas discharge lamps

摘要

Door drive (1), in particular a swing door operator,– with a drive unit (2), which via an output shaft (9) can be coupled with a door and, in a housing (13) is arranged,– with a motor (3), which is connected with the drive unit (2) is in drive connection,– with a in the housing (13) arranged spring tension accumulator (4) to said motor (3) and the drive unit (2) is coupled to and– with a hydraulic pump (5) to said motor (3) is drivingly connected,– the hydraulic pump (5) in the form of a proportional to the piston pump is formed, which with one of the drive unit (2) associated first pressure chamber (6) and a the spring tension accumulator (4) associated separate at least second pressure chamber (7) is in hydraulic connection, as well as– by means of a fire protection - release device (28), between a working hydraulic system - circuit (25, 22, 7, 23, 6) and a pressureless tank space (29) is arranged.