WE CLAIM:
1. A filter device comprising:
a first tube having holes on the side surface thereof;
5 a second tube inserted through said first tube and protruding from the
proximal end side of said first tube in the longitudinal direction thereof;
a filter arranged such that said filter has a closed end portion on the proximal
end side in the longitudinal direction of said first tube, and such that the distal end
side of said filter in said longitudinal direction forms an opening;
10 a ring fixed to said opening and having elasticity or shape memory property;
first wires inserted between said first tube and said second tube, wherein the
proximal ends of said first wires are fixed to said second tube, and the distal ends of
said first wires protrude from the distal end side of said first tube in the longitudinal
direction thereof and are fixed to portions of said ring; and
15 second wires inserted between said first tube and said second tube, wherein
the proximal ends of said second wires are fixed to said second tube, and the distal ends of said second wires protrude from said holes and are fixed to portions of said ring;
wherein said opening can be opened and closed in the form of a bag when the
2 0 proximal end side of said filter in the longitudinal direction is defined as the bottom,
and said opening can be closed by pulling said second tube towards the proximal end side in the longitudinal direction.
2. The filter device according to claim 1, wherein said holes are arranged so as
25 to form equal angles relative to the central axis of said first tube, and arranged on the
same circumference.
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3. The filter device according to claim 1 or 2,
wherein said ring has a cylindrical shape, and
wherein the fixed positions of said first wires to said ring, and the fixed
positions of said second wires to said ring, are arranged alternately relative to the
5 central axis of said first tube.
4. The filter device according to claim 1 or 2,
wherein said ring includes a plurality of mountains facing the distal end side
in said longitudinal direction, and aiplurality of valleys facing the proximal end side
10 in said longitudinal direction, which mountains and valleys are formed alternately,
wherein the fixed positions of said first wires to said ring are provided at the apices of said mountains, and
wherein the fixed positions of said second wires to said ring are provided at the bottoms of said valleys. 15
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