Control system for electrically-driven vehicle - uses voltage divider with magnetic, sequentially-operated switching contacts with series resistances

摘要

The control system for an electrically driven vehicle includes a desired value unit having four series resistances (R1 to R4) forming a voltage divider. At the junction points between the resistances are connected switching contacts (S1 to S5) each in series with a further resistance (W1 to W5). The ends of all these latter resistances, remote from the switches are all connected by a common line to an output point (A). The switches are operated in sequence, and when all switches are open, the latter resistances ensure that there is not a false reading in the absence of a current flow. Either one switch or two adjacent contacts can be operated sequentially. The contacts can be magnetically operated vacuum contacts, or can be moved by a sliding permanent magnet.