When the trimming bottom line is short, check the cutting depth first. The shallower the cut, the shorter the bottom line. Secondly, check whether the sewing fork is tightened too tightly. You can pull the bottom thread by hand with a suitable bottom thread Zhang Liwei sewing fork. In addition, check whether the shuttle shell is deformed, which will affect the tension of the bobbin thread when rotating.

There may be two reasons for continuous thread cutting: first, check the depth of cutting tool, which is too shallow to cut thread; Second, change the parameters and check whether the parting angle is between 3 10 and 3 15. Mitsubishi computer pattern machine, the abnormal thread cutting in the control system of computer pattern machine is generally manifested as top line short thread cutting, bottom line short thread cutting or continuous thread cutting.

The trimming surface is short. The length of the upper thread and the tension of the thread take-up spring are closely related to the adjustment of the thread path. When the thread diameter is tight and the tension of the thread take-up spring is large, the upper thread will become shorter. Short-line trimming surface can be adjusted in the following ways:

(1) Adjust parameters and operating angles. The larger the cutter closing angle, the longer the upper surface line.

(2) Check the rail, and don't tighten the take-up spring and knob;

(3) Adjust the height of the buckle fork, and the upper thread will be longer if it is raised a little;

2. How to adjust the bottom line trimming of computer flat car if it is too short?

Method: 1 Stop the needle.

The small clamp should not be too tight. Secondly, see if the big clamp is pushed away when cutting the line.

If not, push the clamp inward, but not too far, otherwise the slightly thicker fabric will jack up the clamp and make the thread float under the fabric. The main advantages of computer flat car are: due to the control of computer, the requirements of manufacturing enterprises for technicians have been greatly reduced. The most common electromechanical integration of automobiles-the so-called electromechanical integration-is to combine the application of mechanical technology and electronic technology.

Ordinary flat cars don't have these benefits, and there seems to be nothing to say about this. In the sewing machine industry, the so-called mechanical and electrical products are mainly computer sewing machines, and some of them are fine in workmanship, as everyone should know.

Computer flatbed has low noise. Simple operation.

Computer flatbed can be set up, which can create a good working environment for workers and simplify things that were done by skilled workers in the past. This is the so-called "flatbed car". Compared with other industrial electric sewing machines, single needle zipper flat car.

Automatic thread cutting sewing machine, using computer sewing machine not only saves electricity, but also automatically cuts thread without shearing hair. Summary: Computer flat car can be set.

Simple operation, automatic thread cutting, no hair cutting. Ordinary flat cars do not have these benefits.

3. How to repair the broken bottom line of computer sewing machine?

The sewing machine is always broken, and the bobbin thread winding can be solved by referring to the following methods.

Fault characteristics of 1: the bottom line cannot be drawn.

Product reason:

The shuttle thread is too short, the shuttle clip is attached to the shuttle door, the needle is too high, and the shuttle can't hook the thread loop.

Treatment: lengthen the shuttle thread, check whether the bottom thread is stuck and eliminate it. The fastening screw of the needle bar connecting shaft is loose. If the needle bar moves upward, lower the needle bar, recalibrate the needle and tighten the fastening screws.

2 Fault features: needle bar moves.

Product reasons: needle bar hole, needle bar wear, needle bar connecting screw loose, needle bar displacement.

Treatment: replace the needle bar sleeve, or select a new needle bar and re-align the needle; And tighten the fixing screws.

Fault characteristics: jump a needle and thread after a few stitches.

Product reason: the shuttle is worn, the shuttle tip is too blunt, and the sewing needle is too high or too low.

Treatment: replace the shuttle, adjust the height of the needle bar or machine needle, and re-align the needle.

Fault features: continuous jumper or one stitch can't be sewn.

Product reason: the needle quality is poor or the bending needle can't loop normally. The sewing needle is too high to hook the coil, and the sewing needle is not properly matched. Long-term use of shuttle, workbench and other parts is seriously worn or damaged.

Treatment: Replace qualified machine needle or straightening machine needle. Adjust the height of needle bar or sewing machine needle. one

Under normal circumstances, the shuttle bed can be replaced or overhauled if necessary.

Fault features: thin joints have no jumpers, while thick joints have jumpers.

Product reasons: insufficient presser foot pressure, too thin sewing needle, serious wear of hook mechanism and other parts.

Treatment: adjust the presser foot pressure, replace the needle, replace the parts and repair.

Fault features: thick jumper and thin jumper.

Product reason: the pin hole of the needle plate is worn too much, the needle of the sewing machine is too thick, the bottom of the presser foot is worn, or the presser foot pressure is too small.

Treatment: replace the needle plate, fine needle, presser foot, presser foot or adjust the presser foot pressure.