Abstract: A procedure for damping the vibrations of an elevator car or part supported by elastic suspension elements comprises the steps of measuring the acceleration of the elevator car or part by means of at least one acceleration transducer, using the output signal from that transducer to control at least one vibration damper, which, in order to damp a vibration, imparts to the elevator car or part a force acting in a direction opposite to the direction of the vibration and substantially simultaneous with it. An apparatus to carry out the procedure is also disclosed.

Abstract: A way of placing chokes with air core, such as thyristor commutating chokes, in a three-phase alternating current rectifier. With a view to eliminating the drawbacks of air-core chokes especially in three-phase rectifying applications, the three chokes of three phases, wound in the same winding direction, are placed on one and the same plane at the corner points of an imagined triangle which brings the chokes as close together as possible.