Sewing machine needle clamping device

A sewing machine needle clamping device for attaching a sewing machine needle to an accommodating recessed part of a needle clamp with the needle clamp comprising the accommodating recessed part accommodating a needle shank of the sewing machine needle, comprising:

• a clamp lever which can rock freely and has a clamp arm which engages to the needle shank of said sewing machine needle, is freely opened and closed for said accommodating recessed part and is fixed to a clamp lever shaft which is fitted loosely to an elongate hole which is bored at said needle clamp, and
• a needle fixing spring which repels elastically said clamp lever to an outer direction of a straight line which links a central point of the needle shank of said sewing machine needle and a central point of said clamp lever shaft, wherein
• the clamp arm has a force acting locking part,
• sliding on the needle shank of said sewing machine needle against elasticity of said needle fixing spring when rocking said clamp lever to a clamping direction in a state that the needle shank of said sewing machine needle is engaged to said accommodating recessed part and butted in the attaching position of a vertical direction, and
• passing a branch point position that the elasticity of said needle fixing spring of the straight line which links the central point of the needle shank of said sewing machine needle and the central point of said clamp lever shaft becomes maximum, and
• holding a stable clamping state by the elasticity of said needle fixing spring.