Heating energy controlling method for electrically heatable flat wiper blade of windscreen wiper system of road vehicle, involves controlling preheating time such that time increases with diminishing temperature

摘要

The method involves operating an electrical heating element (3) e.g. heating wire and heating foil, during a preheating phase or a preheating time with increased heating energy and with reduced continuous heating energy in a temperature range between a general temperature threshold value and an additional temperature threshold value lying above a freezing point and below the threshold value. The preheating time is controlled in a temperature-dependent manner such that it increases with diminishing temperature.