ZWEISTUFIGER SCHERENSTROMABNEHMER

摘要

1. A two-stage pantograph, with an upper fork bearing with regulated constant contacting force through a current collector rocker (4) on an overhead power line (2), a main fork (6, 7) carrying aforesaid upper'fork, a first adjusting device (14) associated with the upper fork, a control device (17) transmitting adjustment signals to said adjusting device for maintaining constant the said contacting force, as well as a second adjusting device (15) associated with the main fork (6, 7), characterised in and by a second control device (23) which supplies to the second adjusting device (15) control signals for maintaining a temporally averaged adjusting distance of the first adjusting device (14) to act as preset nominal value and to which are fed as measured quantities the actual value of the adjusting distance of the first adjusting device (14) and the actual value of the acceleration of the main fork (6, 7), and in which the control signals for the second adjusting device (15) are derived with the aid of an additive linear function from the actual value of this acceleration and the difference between the actual and nominal values of the adjusting distance of the first adjusting device (14).