Patent ID: 7374722

Claim:
System for taking a gas sample likely to contain particles of suspended materials for which it is desired to count and/or be analysed by means of an analysis device including a suction pipe for sucking up said sample, said system comprising a tubular column delimiting a passage section and said column having a bottom connected to said suction pipe and a sampling head located opposite to said bottom, wherein said column successively comprises starting from said head a first impact separator having a first truncated deflector which reduces said passage section in the direction of said bottom and a collector provided with and impact head situated below said deflector in a central part of said column to extract particles whose diameter is larger than a first diameter and a second separator located below said first impact separator and comprising a second deflector which reduces said passage section in the direction of said bottom and a second collector comprising an annular extraction chamber having an annular opening located below said second deflector and debouching in said column to eliminate the finest particles whose diameter is smaller than a second cut-off diameter and to concentrate in a gas flow sucked up by said suction pipe particles having a diameter larger than said second cut-off diameter.