Temp. indicator for power drill overload protection - has light emitting diodes as indicators combined to give numerical read out

摘要

The visual indicating monitoring unit for electrical tools is esp. designed to provide overload protection for pistol grip drill. This is achieved by incorporating in the tool a temp. sensitive element which provides visible numerical readout when a critical temp. is reached. The element comprises liq. crystals pref. light emitting diodes (1) which are combined in the drill housing to provide one or more symbol readouts. The elements can be glued or screwed to the drill. The safety device is designed to switch off the drill's power unit when the external critical temp. e.g. 53 deg.C, is attained.