A sewing machine needle is attached firmly and easily, and is fixed and exchanged. A needle clamp 5 for clamping a sewing machine needle 3 has an accommodating recessed part 7 which accommodates a needle shank 15 of the sewing machine needle, a clamp lever which has a clamp arm 21 which engages to the needle shank, is freely opened and closed and is fixed to a clamp lever shaft 17 which is fitted loosely to an elongate hole which is bored at the needle clamp for the accommodating recessed part and a needle fixing spring 23 which repels elastically the clamp lever to an outer direction of a straight line which links a central point N of the needle shank and a central point of the clamp lever shaft, and the clamp arm has a force acting locking part 22 which slides on the needle shank of the sewing machine needle against elasticity of the needle fixing spring when rocking the clamp lever to a clamping direction a and passes a branch point position tp that the elasticity of the needle fixing spring of the straight line which links the central point of the needle shank of the sewing machine needle and the central point of the clamp lever shaft becomes maximum and holds a stable clamping state by the elasticity of the needle fixing spring.

A sewing machine needle is attached firmly and easily, and is fixed and exchanged. A needle clamp 5 for clamping a sewing machine needle 3 has an accommodating recessed part 7 which accommodates a needle shank 15 of the sewing machine needle, a clamp lever which has a clamp arm 21 which engages to the needle shank, is freely opened and closed and is fixed to a clamp lever shaft 17 which is fitted loosely to an elongate hole which is bored at the needle clamp for the accommodating recessed part and a needle fixing spring 23 which repels elastically the clamp lever to an outer direction of a straight line which links a central point N of the needle shank and a central point of the clamp lever shaft, and the clamp arm has a force acting locking part 22 which slides on the needle shank of the sewing machine needle against elasticity of the needle fixing spring when rocking the clamp lever to a clamping direction a and passes a branch point position tp that the elasticity of the needle fixing spring of the straight line which links the central point of the needle shank of the sewing machine needle and the central point of the clamp lever shaft becomes maximum and holds a stable clamping state by the elasticity of the needle fixing spring.

A needle bar 4 is supported by a needle bar supporter in a manner freely movable up and down relative to a frame. A crank 2 is fixed to an upper shaft 1, rotates with the upper shaft 1, and an output end thereof moves circularly. A crank rod 3 is connected to the crank 2 in a freely rotatable manner. A connection rod 8 is connected to an intermediate portion of the crank rod 3 in a freely rotatable manner, and is connected to the needle bar 4 in a freely rotatable manner. A length of the needle bar 4 and a length from a connecting position of the connection rod 8 and the crank rod 3 to a slider 7 differ. When the crank 2 circularly moves, the connecting position of the connection rod 8 and the crank rod 3 draws a trajectory of an ellipse.

A needle bar 4 is supported by a needle bar supporter in a manner freely movable up and down relative to a frame. A crank 2 is fixed to an upper shaft 1, rotates with the upper shaft 1, and an output end thereof moves circularly. A crank rod 3 is connected to the crank 2 in a freely rotatable manner. A connection rod 8 is connected to an intermediate portion of the crank rod 3 in a freely rotatable manner, and is connected to the needle bar 4 in a freely rotatable manner. A length of the needle bar 4 and a length from a connecting position of the connection rod 8 and the crank rod 3 to a slider 7 differ. When the crank 2 circularly moves, the connecting position of the connection rod 8 and the crank rod 3 draws a trajectory of an ellipse.

A needle clamp (1) for sewing machine (100) is provided. The needle clamp (1) comprises a body (2) at least partially made of a thermally conductive material and having retaining means (3) for constraining at least one needle (10). The needle clamp comprises a thermoelectric cooling device (5) directly or indirectly constrained to a portion of said body (2).

A needle clamp (1) for sewing machine (100) is provided. The needle clamp (1) comprises a body (2) at least partially made of a thermally conductive material and having retaining means (3) for constraining at least one needle (10). The needle clamp comprises a thermoelectric cooling device (5) directly or indirectly constrained to a portion of said body (2).

A sewing machine includes a material sandwiching unit to sandwich two materials having annular edges from above and below while they are stacked so that the material on an inner wheel side is located on the lower side and the material on an outer wheel side is located on the upper side, wherein a part of the material sandwiching unit located above the two materials is vertically movable, the material sandwiching unit includes a curl-removing mechanism to straighten curls occurring on the edges of the two materials, the material sandwiching unit includes inclined parts that serve as the curl-removing mechanism and have edges extending backward from a farther side of the edges toward the edge side at a position where the two materials pass therethrough, and the inclined parts have air ejectors to eject air so as to form airflows that straighten portions of the materials where curls have occurred.

A sewing machine includes a material sandwiching unit to sandwich two materials having annular edges from above and below while they are stacked so that the material on an inner wheel side is located on the lower side and the material on an outer wheel side is located on the upper side, wherein a part of the material sandwiching unit located above the two materials is vertically movable, the material sandwiching unit includes a curl-removing mechanism to straighten curls occurring on the edges of the two materials, the material sandwiching unit includes inclined parts that serve as the curl-removing mechanism and have edges extending backward from a farther side of the edges toward the edge side at a position where the two materials pass therethrough, and the inclined parts have air ejectors to eject air so as to form airflows that straighten portions of the materials where curls have occurred.