| 摘要 |
A fabric presser device of a sewing machine is provided to set the optimum pressurizing force in simple corresponding to the change of thickness in the cloth to be sewed, thereby enhancing the working efficiency. A presser member has a presser foot and pressurizes and maintains the cloth to be sewed. A stepping motor includes an encoder equipped to the inside thereof. A power transfer mechanism transfers the driving force of the stepping motor to the presser member. A control member(70) controls the stepping motor. The control member includes a memorizing member(71) for memorizing the setting value of the pressurizing force applied to the cloth to be sewed by the pressure foot. A calculating member(73) calculates the pressurizing force from the prearranged pulse phase of the stepping motor set by the control member and the real phase outputted by the encoder. The setting value is set by a worker through an input interface. The memorizing member memorizes the high speed falling permission value as the reference value for performing the high speed falling of the presser foot when the deviation between the input pulse phase and the real phase is below the constant value.
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