Switch mechanism for vehicle windscreen wipers - has energy measuring unit with switch to cut off drive when current is excessive

摘要

The wiper mechanism has a drive system and an energy co conduction lead. Excessive wear on the wiper blades and drive system is prevented by an automatic switching off mechanism. This operates when an energy measuring element in the conducting lead records that a prescribed value has been exceeded. The normal drive unit is an electric motor and an-meter is used with an overload switch. An extension to the design has a circuit to establish the mean energy requirement and the cut off switch is operated when the current is more than the acceptable difference between the maximum and mean figures.