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(11) | EP 2 241 662 A3 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Thread cutting device for sewing machine |
| (57) The invention relates to a thread cutting device for a sewing machine. The thread
cutting device includes: a cutting knife including a cutting edge and serving to carry
out a rotation to an initial position and a thread cutting position advanced from
the initial position to a stitch point side; a moving knife rotated to the initial
position, a thread catching position advanced from the initial position and the thread
cutting position retreated from the thread catching position in order and serving
to cut a bobbin thread and a needle thread in cooperation with the cutting knife in
the thread cutting position; and a clamp member for interposing and holding the bobbin
thread between the clamp member and the moving knife by an elastic force applied through
an elastic deformation, the clamp member including a first interposing portion for
interposing the bobbin thread between the first interposing portion and the moving
knife when the moving knife is returned from the thread cutting position to the initial
position. The moving knife includes a catching portion for catching the bobbin thread
in the thread catching position. The clamp member includes a second interposing portion
for interposing the bobbin thread in abutment on a first abutting portion provided
on a tip side of the moving knife from the catching portion when the moving knife
is placed in the thread cutting position. The bobbin thread interposed by the second
interposing portion in the thread cutting position is transferred to the first interposing
portion and is held by the first interposing portion with a movement of the moving
knife to the initial position.
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