Knowledge Of Four Arm And Six Wire Sewing Machine

It belongs to the high-end garment sewing industry. Its special sewing principle and crank type small tube structure are widely used in high-grade underwear, underwear, long tube silk and so on.

The machine has strong seams, neat edges, no edges, beautiful stitches, and perfect stitching with multiple processes, so it is well received by high-end users.

However, because of its complex structure and high accuracy, it is relatively difficult to debug.

In order to enable users and maintenance personnel to have a deeper understanding of the machine, so as to better judge and deal with the problems arising in the use process, we will do the following analysis of its internal structure and the working principles between the organizations, hoping to help our friends.

The four needle six line sewing machine can be divided into two types: single cut and double cut according to the cutting method.

Its main structure and basic principle are the same. The difference lies in the change of the cloth guiding device and the presser foot.

The whole machine can be decomposed into three main institutions: needle bar spear and thread picking mechanism, differential feeding and adjusting mechanism and bending needle hook mechanism.

The following is a detailed description of the timing coordination between the three institutions and institutions.

There is an eccentric crank on the crankshaft. When the crankshaft rotates clockwise, the force is passed to the needle bar lever by connecting with the lever connecting rod assembly 3, and the cutter shaft linkage 5 is used as the fulcrum to swing up and down.

The needle bar shaft lever is connected with the needle bar connecting rack 7 through the needle bar connecting rod 6, and the needle bar 9 is locked tightly by the needle bar Chuck Screw in the needle bar chuck, so that the needle bar moves upward and downward with the rotation of the crankshaft.

The adjustment of the straight needle position can be done by loosening the screw 8 on the chuck 7 of the needle bar, and the needle bar can move up and down in the chuck hole so as to adjust the height of the needle; and the size of the needle stroke is controlled by the size of the parts, and is not adjustable. The standard stroke of the needle bar is 30 millimeters in this series of models.

It is connected with the cutter drive connecting rod shaft 5. When the needle bar reaches the highest point, the take-up rod is also in the highest position. When the needle bar reaches the lowest point, the take-up rod is also at the lowest position.

From this structure, we can know that the timing of picking thread is synchronous with needle bar and can not be adjusted.

How do we adjust the timing of loosening and tightening the wire loop? This problem will be explained in the later debugging section.

The differential adjustment mechanism is mainly used for adjusting the mechanism of delivering cloth function and adapting to various elastic fabrics.

The following is a comprehensive analysis of the organization first, and then decompose it to better understand its working principles.

The movement of the feeding teeth and the differential teeth is completed by two groups of mechanisms. One group is the lifting mechanism to complete the movement up and down, and the other is the feeding mechanism to complete the movement in the front and rear direction.

The feeding teeth and the differential teeth form an elliptical motion track under the action of the combination of the two groups of forces, thus completing the whole process of delivering cloth.

When the spindle 1 rotates clockwise, the lifting tooth eccentric wheel and the lifting tooth connecting rod assembly are driven to move up and down, and the feeding rack 5 and the differential rack 8 will swing up and down as the pivot point with the movement of the tooth lifting connecting rod 3, and the feeding teeth and the differential teeth will form the movement of the lifting teeth.

When the feeding eccentric wheel rotates with the main shaft, the feeding connecting rod assembly is driven, and the feeding tooth adjusting seat is driven to rotate around the feeding lever shaft for reciprocating rotation.

The feeding crank connecting rod 15 passes through the hinge connection and the needle pitch adjusting screw, pfers the swing of the feeding tooth adjusting seat 12 to the feeding crank, and makes the swing with the feeding shaft as the axle center, and completes the cloth feeding movement in the front and rear direction.

The feeding distance is adjusted by adjusting the center distance between the adjusting screw and the feeding lever shaft.

The swing angle changes the movement of the horizontal movement of the feeding tooth and the differential tooth, thereby achieving the purpose of adjusting the needle distance.