| 摘要 |
A longitudinally adjustable leg assembly, comprising a holder (9, 12) which is adapted to be fixed to the underside of a table top (1); first and second elongate carrier elements (2, 3) which are directed away from the holder (9, 12) and cooperate by threaded engagement. The first carrier element (2) is mounted rotatably but axially immovably in the holder (9, 12) and one (2; 3) of the first and second carrier elements (2, 3) having an external thread and the other (3; 2) of the first and second carrier elements (2, 3) being a tube having an internal thread portion at one end in threaded engagement with the external thread. An electric motor is arranged for rotating the first carrier element (2). A device is arranged for interrupting the current to the motor when the leg assembly is in a limit position of maximum or minimum length. The device comprising two switches (19, 20) and an actuator (21), which is adapted to actuate one of the two switches (20) when the leg assembly is in the limit position of maximum length and the other of the two switches (19) when the leg assembly is in the limit position of minimum length. A limit position wire (25) is attached to the actuator (21) for controlling the same when the leg assembly is in its limit position of maximum length.
|
