What are the failures of the computer pattern machine sewing process
1. The tip of the curved needle is round and bald
2. The needle hole on the needle board is too small to cause the needle to break
3. The pressure of the presser foot is too small, resulting in poor feeding of the pattern machine
4. The curved needle of the pattern machine collides with the straight needle
5. The tension needle of the pattern machine collides with the straight needle
6. The straight needle of the pattern machine does not work properly with the needle guard
7. The needle bar and needle bar sleeve of the pattern machine are worn too much, which makes the needle bar and needle bar sleeve loose.
8. The parts of the pattern machine are loose, and there is abrasion between the parts of the hook thread organization
Computer pattern machineThe reasons for skipped stitches are:
1. The needle plate hole is too large, and high-speed sewing will cause skipped stitches.
2. The needle eye of the computer pattern machine is too small to form a loop.
3. The needle of the computer pattern machine is bent, causing the wrong position of the upper thread and the lower thread.
4. The height position of the needle bar of the computer pattern machine causes the threading timing of the needle and the hook to be incorrect, and the upper and lower threads do not form a correct time intersection, resulting in no need to hook the upper and lower threads.
5. The working material is too thick and the needle type is too small, which changes the forming time of the thread loop.
6. The lock tip of the rotary hook is bald and short, causing stitch skipping during over-post sewing and corner sewing.
7. Straight stitches skip stitches at the seam head.
8. Skipped stitches caused by the loose thread cam
There are two types of disconnection, one is regular disconnection and the other is irregular disconnection.
Regular disconnection includes:
1. The clearance between the needle and the hook is incorrect, and the needle position is too high or too low, and needs to be readjusted.
2. There are burrs in the needle hole and needle plate hole, the rotary hook has burrs, and the positioning hook has burrs.
3. The thread passing part is not smooth, including the thread clamping plate, thread clamping screw, thread take-up rod hole, upper and lower thread guide, etc., all are not smooth
Slippery or burrs should be smoothed or replaced.
4. The needle is reversed and needs to be reinstalled correctly, the needle tip is damaged, the needle is stained with glue, and the needle is replaced.
5. The thread take-up cam is damaged. Replace the thread take-up cam.
6. The hook shaft moves.
7. There are scratches and damages on the thread passing surface of the rotary hook.
Irregular disconnection includes:
1. The environmental humidity is too high, the line is damp, dehumidify, and replace with a new line.
2. Unreasonable pattern-making and needle-moving. Revised.
3. The thread quality does not meet the requirements, and the thread after installation does not meet the requirements. The embroidery thread is too thick and does not match the needle specifications. change
4. The moving frame curve and moving frame angle are unreasonable, adjust the computer parameters.
5. There is a gap in the transmission of the upper and lower shafts or the shaft is broken, causing the machine head and the rotary hook to be out of sync. Check the gear box, adjust the chain tightness or the timing belt of the gear box.
6. The surface of the embroidery thread is rough. Add silicone oil to the surface of the embroidery thread.
Blocking the thread means that the thread is balled up under the needle plate, blocking the pinhole, and the result is the thread breaking.
1. The gap between the positioning hook and the shuttle frame is unreasonable. readjust.
2. The embroidery is too thin or too loose, and the needle plate hole is too large. Pad two or three layers of non-woven paper.
3. Deduction line fails. Check the deduction
4. The bottom line is too loose, and the exit direction is wrong. Adjust the bottom line.
5. There is debris or deformation in the bobbin case, which causes the bobbin to rotate poorly and easily break the bottom thread.
1. The tension of the upper thread and the bottom thread is too small or too loose. Adjust the tension.
2. The line quality is not good. Change the line.
3. Insufficient lubrication of the hook. Add white oil (twice per shift)
Pattern shift, deformation and treatment plan
There are many types of pattern shifting, such as X-direction displacement, Y-direction displacement, overall displacement, individual head displacement, single-direction displacement, irregular displacement and so on.
1. The overall displacement in the X direction, mechanical failures include: the stepper motor coupling is loose, the timing belt is too loose or too tight, the timing wheel bearings, prismatic bearings, and stretcher bearings are damaged, and the guideway gap is too large.
2. Overall displacement in Y direction, the fault is the same as X direction, but the direction is different.
3. The overall displacement, in addition to mechanical reasons, there are also electronic control failures and pattern-making reasons. The electronic control part failures include:
① If the memory fails, the computer memory pattern needs to be cleared and formatted. Then re-enter the pattern. Generally, the computer should not store too many patterns, and the storage time should not be too long. The patterns should be cleaned and formatted regularly.
② Interference caused by power grid interference, leakage of electromagnets or other electrical components. Need to find the source of interference to eliminate the interference.
③ The power failure protection is not set, and the sudden power failure requires repositioning and find the original position. ④ The stepper motor is faulty. Most of the reasons are that the stepper motor driver is damaged. Repair or replace the driver.
⑤ If the encoder fails, self-check the encoder in the computer.
How to solve the short pinhole of thread after thread trimming
1. From the simplest place, check whether the small thread clamp is too stressed. The small thread clamp controls the length of the thread end. If the pressure is too high, the thread end is too short, and the thread end will come out of the needle hole during the second sewing.
2. When the thread trimming electromagnet is working, pay attention to see if the large thread clamp bounces off. If it does not pop open, push the large thread clamp inward a little less.
3. Pay attention to check whether the position of the tangent cam is correct. There is a great possibility of problems in this place.
4. Check whether the hand wheel is installed correctly and the sensor at the hand wheel is installed correctly.
5. If it is a brother's computerized sewing machine, or a computerized flat car that imitates the brother, pay attention to whether the movable knife is installed at the front end, that is, the thread is cut too early.
6. If it is a heavy machine or imitated heavy machine, pay attention to whether the fixed knife installation position is on the far left.
7. Several failures caused by friction plate loss in servo motor
1. The power supply (referring to the computer box) is automatically cut off, but the power indicator on the head of the computer sewing machine is still on, and the motor cannot be placed on the motor when the motor is hot. Two pieces) should be replaced. Sometimes even the power indicator on the head of the sewing machine goes out. The same is true. This refers to the sudden power cut off during the sewing industry.
2. After the computer car is sewn, the thread trimming is performed. The thread trimming action is slow. Sometimes when the thread is trimmed, the computer box automatically cuts off the power supply. This is caused by the excessive wear of the friction plate inside and should be replaced; or there is a friction plate inside. Caused by oil pollution.
3. During sewing, the needle stop position is wrong (refers to the position of the induction coil and the circuit in good condition. When the sewing machine is shipped from the factory, the sewing machine has been positioned at the sewing machine and stopped as the lower needle stop, that is, the needle is below ; After sewing is finished, the needle is stopped up, that is, the needle is on the upper side) or the needle is not positioned correctly after thread trimming, which is caused by dust or oil on the surface of the inner friction sheet.
First: When the needle bar drops to the lowest point and begins to rise, the rightmost needle thread loop is formed at a point, and the curved needle can begin to penetrate. The standard power position is: the relationship between the looper and the left needle is that when the looper swings from right to left to the leftmost needle, its tip is just about 0.5mm~1mm above the threading hole behind the left needle .
Second: Check that the needles of the computer car, computer pattern machine, and computer sewing machine may be slightly skewed, that is, there should be a gap of 0∼0.05mm between the rightmost needle (the shortest inside) and the looper, and the leftmost machine There should be a gap of ﹣0.03mm∼1mm between the needle and the looper, so that there is a deflection angle of 2°∼5°. When the looper starts to swing to the right from the leftmost (dead point), there should be a distance of 1.5mm~2.5mm between the left straight line and the looper eye. At this time, the left straight needle passes through the back of the looper, that is, the straight needle passes through The looper thread is to pass through the loop of the looper triangle, with an interference size of 0∼0.05mm, otherwise it will easily cause skipped stitches.
Third: Due to the large gap between the front guard needle and the straight needle, the formation of the straight needle thread loop is not ideal, and the formation time is slow, causing the straight needle to be unstable when the curved needle passes through the thread loop, and it is easy to misalign and cause skipped stitches; guard part If the position is too high or too low, it is easy to cause the line bubble to fail to be thrown out and cause skipped stitches.