Patent ID: 7504787

Claim:
Squeeze protecting device arranged to detect the presence of an object in a protection area comprising a housing and an antenna unit connected to a detecting circuit, which circuit is arranged to, via said antenna unit, detect capacitive variations in an electric- or electro-magnetic field at said antenna unit, characterised in that said detecting circuit comprises a signal generator that provides a signal to the antenna unit that generates the electric or electro-magnetic field at the antenna unit; balancing means for maintaining the generated electric or electromagnetic field at the antenna unit in a balanced condition; filter means for preventing the detecting circuit from being affected by variations in temperature and moisture; and detecting means for detecting small variations in the generated electric or electromagnetic field at the antenna unit and/or a variation of pressure at said antenna unit caused by a compressive force applied to said housing, wherein the presence of conductive as well as non-conductive objects in said protection area can be detected.