Thread trimming, thread loosening, presser foot lifting and presser foot pressure adjusting device of sewing machine and sewing machine

Abstract

The invention relates to the technical field of sewing machines, in particular to a thread trimming, thread loosening, presser foot lifting and presser foot pressure adjusting device of a sewing machine and the sewing machine comprising the device. The device comprises a power piece, a cam structure, a thread trimming driving crank connected with a thread trimming mechanism and an ejector rod connected with a thread loosening mechanism, a presser foot lifting mechanism and a presser foot pressure adjusting mechanism, a first transmission pin on the thread trimming driving crank is matched witha first driving contour face of the cam structure, and the first driving contour face is provided with a thread trimming driving section for driving the thread trimming mechanism to execute thread trimming action; and a second transmission pin on the ejector rod is matched with a second driving contour face of the cam structure, and the second driving contour face is provided with a thread loosening driving section for driving the thread loosening mechanism to execute thread loosening action, a presser foot lifting driving section for driving the presser foot lifting mechanism to execute presser foot lifting action and a presser foot pressure adjusting driving section for driving the presser foot pressure adjusting mechanism to execute presser foot pressure adjusting action. The four functions of thread trimming, thread loosening, presser foot lifting and presser foot pressure adjusting are achieved through the driving of one power piece.

Description

technical field [0001] The invention relates to the technical field of sewing machines, in particular to a sewing machine thread trimming and thread loosening lifting presser foot and a presser foot pressure adjusting device and a sewing machine. Background technique [0002] Currently, sewing machines use the functions of thread trimming, thread loosening, presser foot lift and presser foot pressure adjustment during the sewing process. Among them, the thread trimming and thread loosening functions are driven by electromagnets, which has the problem of slow response; the function of lifting the presser foot is realized by driving methods such as hand-held, artificial knee rest, electromagnet, and cylinder, and when electromagnets are used, The presser foot lifting function and the thread trimming function are respectively driven by two electromagnets with different powers; the presser foot pressure adjustment function is realized by manual adjustment of the pressure regulat...

AI Technical Summary

Problems solved by technology

Among them, the thread trimming and thread loosening functions are driven by electromagnets, which has the problem of slow response; the function of lifting the presser foot is realized by driving methods such as hand-held, artificial knee rest, electromagnet, and cylinder, and when electromagnets are used, The presser foot lifting function and the thread trimming function are respectively driven by two electromagnets with different powers; the presser foot pressure adjustment function is realized by manual adjustment of the pressure regulating nut

This driving method to realize the four functions of thread trimming, thread loosening, presser foot lift and presser foot pressure adjustment has the disadvantages of complex structure and low working precision.

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