Patent ID: 7592907

Claim:
A metal detector for control of protected access comprising two oblong shape vertical housings ( 10 , 12 ), a structure ( 14 ) connecting the upper part of said vertical housings ( 10 , 12 ) and emitting and receiving electrical coils ( 3 , 5 ) provided in said housings ( 10 , 12 ), characterized in that each of the two housings ( 10 , 12 ) which comprises two separate emitting ( 3 ) and/or receiving ( 5 ) coils, wherein the coils operate so that each of the two housings ( 10 , 12 ) comprises one emitting coil (TX) and one receiving coil (RX) and the detector comprises means controlling operation of said emitting and receiving coils so that when an emitting coil (TX 1 , TX 2 ) provided in a housing ( 10 , 12 ) is active, the two receiving coils (RX 1 , RX 2 ) provided respectively in both the two housings are also simultaneously or subsequently active.