| 摘要 |
The processing circuit proposed for a differential throttle travel control device comprises the following components: a) a first output terminal (A1); b) a first oscillator (OSZ1) which produces at the first output terminal (A1) a first alternating voltage which has a constant frequency and its amplitude can be adjusted by means of first amplitude adjustment means; c) a second output terminal (A2); d) a second oscillator (OSZ2) which produces at the second output terminal (A2) a second alternating voltage which has the same frequency as the first alternating voltage, its phase is displaced by 180 DEG with respect to that of the first alternating voltage and it can be adjusted by means of second amplitude adjustment means; e) an input terminal (E) for feeding in an input signal; f) a phase-controlled rectifier (PG), which is connected to the input terminal, for rectifying the alternating-voltage component of the input signal; g) a comparator (AG) which is connected to the rectifier, receives the rectifier output signal as a reference signal and compares this signal with a measured signal to produce a deviation signal and; h) an integrator (I) which is connected to the comparator in order to integrate the deviation signal and which supplies the integrated signal as an amplitude adjustment signal to the amplitude adjustment means of both oscillators so that the amplitude of the voltage at one ouput terminal increases by exactly the amount that the amplitude of the voltage at the other ouput terminal decreases, the sum of the amplitudes thus remaining constant. This processing circuit makes it possible to connect up a differential throttle travel control device directly, without the need for a resistance network or d.c. source. A measurement signal without ripple is obtained which changes in proportion to the distance travelled by the control rod (VS) of the control unit (DDWG), the characteristic not being falsified with respect to earth on account of parasitic capacitances. |
