Abstract: An escalator or passenger conveyor step is formed from a polymer-fiberglass composite which is injected into a mold cavity conforming to the configuration of the step. The preferred polymer is a polyethylene terephthalate, and the composite has a significant amount of a glass fiber reinforcement component incorporated therein. The step is provided with tread-stiffening ribs which support the underside of the tread and are interconnected with the step struts on which the step chain axle and trailer roller axles are mounted; and an inverted arch assembly beneath the edge of the step distal of the step riser.

Abstract: A monitoring apparatus for a safety device for driving a vehicle in reverse comprising at least two transmitter/receiver pairs which are mounted at the back of the vehicle and which operate by reflecting sound. Each transmitter/receiver is associated with an electroacoustic transducer. An acoustic shunt is positioned between neighboring transducers. The transmitter/receiver pairs alternate cyclically to acquire an object. The signal received from a neighboring transmitter is evaluated as a function control signal.

Abstract: A noncontact electronic switching arrangement is provided with an oscillator which can be damped by external objects. In accordance with the invention, the oscillator can be excited externally and is coupled to an evaluation circuit and an amplifier. A frequency control, which may consist of a phase-locked loop module, is connected to the externally excited resonant circuit of the oscillator. A reference voltage comparator at the output of the oscillator delivers at a Schmitt trigger output, pulse signals to a retriggerable time delay stage, or a shift register, which are connected to an exclusive-OR stage. The functioning of the exclusive-OR stage can be programmed. The arrangement is particularly useful as a limit or end switch for machine tools.