IN-LINE FILTER DEVICE

PROBLEM TO BE SOLVED: To provide an in-line filter device having a filter means contrived so as not to return dust sucked once on either case upon vacuum sucking or upon vacuum breaking. SOLUTION: The in-line filter device is provided with an in-line filter device main body in which two passages communicating an input port side and an output port side are disposed, a first check valve function part which is disposed on one side passage and permits only communication from the input port side, a second check valve function part which is disposed on the other side passage and permits only communication from the output port side and a filter element which is disposed between the second check valve function part and the output port side. The two passages are formed in parallel or concentrically in the in-line filter device main body. A means for visual observation of the filter element is disposed on the in-line filter device main body. COPYRIGHT: (C)2006,JPO&NCIPI