Safety switching systems for preventing serious misalignment of adjustable control pedals in automotive vehicles

Abstract

Some automobiles have mechanisms for adjusting the height of accelerator and brake pedals, and any clutch pedal, so that drivers large and small can adjust the pedals to the best height. All pedals are adjusted by a single reversible electric motor having a shaft connected directly or by a flexible shaft to the adjusting mechanisms. If any fault develops in any mechanism, the pedals may not be adjusted to the same height, which is hazardous to the driver. A safety switching system detects any serious misalignment of the pedals and de-energizes the motor. The system comprises separate switches which are operable by adjustment of the pedals, and are electrically connected in series with the power supply circuit for the motor. When the pedals are aligned, the bridging contactors of the switches are aligned and are effective to maintain the electrical continuity of the motor circuit. Each contactor has three contact sliders which successively engage staggered tabs on contact strips for the respective pedals. Each contactor has a fourth slider for continuously engaging a separate common contact connected to the power supply circuit whereby the switches are in series therewith. If a fault develops in the drive for any pedal, the contactors of the switches become misaligned which interrupts the supply of electrical power to the motor and prevents adjustment of the pedals until the fault is corrected.