Hook thread mechanism of sewing machine

Abstract

The present invention provides a thread hooking mechanism of a sewing machine, which comprises: a rotary hook shaft and a rotary hook assembly placed on the rotary hook shaft; a revolving drive wheel and a first gear are arranged on the revolving shaft; On the rotating shaft and relatively free to rotate relative to the revolution shaft, one end of the rotation sleeve shaft is provided with an autorotation drive wheel, and the other end is provided with two second gears, both of which are meshed with the first gear; sleeved on the revolution shaft And the third gear and the fourth gear connected coaxially, the third gear meshes with the two second gears; the fifth gear is rotated, the fifth gear meshes with the fourth gear; The sixth gear and the seventh gear connected coaxially on the rotating shaft, the sixth gear meshes with the fifth gear, and the eighth gear connected with the hook shaft transmission, the seventh gear meshes with the eighth gear. The invention can simultaneously realize the revolution and rotation of the rotary hook assembly by driving the revolution shaft and the rotation sleeve shaft.

Description

technical field [0001] The invention relates to the technical field of sewing machines, in particular to a thread hooking mechanism of a sewing machine. Background technique [0002] According to whether the axis position of the upper and lower axes of the sewing machine changes, the sewing machines currently on the market can be divided into two categories. The first category is that the upper and lower shafts rotate automatically, but the axis of the hook shaft is not moving. Most of the current models belong to this category, such as lockstitch sewing machines and template machines. The advantage of this structure is that the structure is simple and the cost is low; the disadvantage is that because the rotary hook shaft is fixed, the stitches in the reverse direction or close to the backward direction are inconsistent with the stitches in the forward direction, resulting in unsightly sewing stitches. [0003] The second type is that when the upper and lower shafts rotate...

AI Technical Summary

Problems solved by technology

But this technology also has an obvious shortcoming: the upper section of the sewing machine, that is, the pricking cloth thread take-up mechanism, and the lower section hooking mechanism are separated from each other in mechanical structure, that is, the axis of its revolution shaft is fixed, but the axis of its rotation input shaft The position is changing, so it is impossible to connect the rotation of the upper shaft and the rotation of the lower shaft mechanically. At high speed, the synchronization between the needle bar and the thread catcher can only be realized through a high-precision servo motor and its control system. The stability of this technology is heavily dependent on the stability of the electronic control system

At present, in order to ensure stable performance, it is necessary to use high-quality (such as imported) electronic control systems, resulting in high prices for the whole machine; if you want to improve the cost performance, you can only use general-quality electronic control systems, but in this way, the performance of the machine will be reduced. affected

Images