Glitch to deal with oneself, do not ask a person!
Faults in maintenance of sewing machines (1) faults in feeding
1. Wrinkling of seam materials
Analysis: broken tip of machine needle, excessive tension of bottom line, improper adjustment of differential mechanism.
Treatment: replace the needle, loosen the spring screw and readjust the differential mechanism.
2. The material is "gnawed" to form a grillage mark
Analysis: the tooth tip is too sharp and the pressure on the foot is too high.
Treatment method: the tooth tip and the screw can be ground with oil stone.
3. The wire wool under the sewing material breaks the sound of fiber when sewing
Analysis: the machine needle is broken or too blunt.
Treatment: replace the new needle.
4. The sewing materials are stagnant
Analysis: the feed tooth is too low and the pressure of presser foot is too high.
Treatment methods: raising the feeding teeth, screw adjustment.
Seam back and forth
Analysis: cloth feeding is too high.
Treatment: adjust the feeding teeth.
Back stitch cannot be sewn
Analysis: cloth CAM displacement.
Processing method: adjust the position of the cloth CAM.
7. The seam is irregular and inclined
Analysis: the feeding tooth is installed crooked or the feeding screw is loose.
Treatment: correct the feeding tooth and tighten the feeding screw.
Maintenance faults of sewing machines (ii) : faults in operation
1. Machine head rotation stagnation
Analysis: adding wrong lubricating oil, especially vegetable oil; Too much dirt in the shuttle bed; Connecting rod screws, taper screws installed too tight.
Treatment: refill the sewing machine oil after washing with kerosene; Clean the shuttle-bed; Loosen the screws to ensure clearance.
2. When delivering the turn, half turn is stagnant, half turn is light slippery, or there is a stagnation point for each turn
Analysis: the wire head of the shuttle bed is not only half hysteresis but also violent shaking and noise. The cloth feeding teeth are in a high position or dirt accumulates in the teeth suture, causing the cloth feeding teeth to collide with the needle plate when rising.
Treatment: clean the shuttle bed and add a little oil to the machine; Clean or lower the cloth feeding teeth; Replace or straighten the needle bar.
The nose is stuck and cannot move
Analysis: the placement of the feeding teeth is too close to the front or back, touching the needle plate; Mounting position of needle bar is too high.
Treatment method: adjust the feeding tooth position, re-align the needle, adjust the height of the needle bar.
4. Noise comes from needle mechanism
Analysis: needle bar, needle bar sleeve, small link and so on wear transmission too large; Small connecting rod screw, needle bar crank screw loose.
Treatment: replace the needle bar, needle bar sleeve, small connecting rod and other accessories; Re-tighten small connecting rod screws, needle bar crank screws loose.
5. Noise comes from the feeding mechanism
Analysis: wear or loose of the large pointed taper screw, loose of the needle plate for feeding the tooth, loose of the needle distance adjusting mechanism.
Processing methods: grinding or re-adjusting the large pointed cone screw, re-adjusting the feeding tooth contact plate, re-adjusting or tightening the needle distance adjusting mechanism screw.
6. Noise comes from the swinging shuttle mechanism
Analysis: the gap between the swing shuttle and the shuttle bed is large due to wear, and the gap between the swing shuttle and the swing shuttle holder is too large, resulting in impact.
Treatment method: replace the pendulum shuttle and the shuttle bed, adjust the spacing or replace the swing shuttle and the swing shuttle.
7. General noise
Analysis: upper shaft, lower shaft and sleeve wear, resulting in up and down shaft channeling; Or the machine is short of oil.
Treatment method: replace the upper shaft, lower shaft and shaft sleeve, or adjust the gap between the upper and lower shaft planes, pay attention to maintenance and add lubricating oil on time.
Fault of sewing machine maintenance (3) fault of line mark
1. The surface line is floating
Analysis: the clamp pressure is too low.
Treatment: screw the clamp line, increase the tension of cotton thread.
The bottom line is floating
Analysis: the bobbin spring is too loose.
Treatment: screw the bobbin spring screw to increase the tension of the bobbin thread.
3. Short stitch length
Analysis: the pressure on the foot is too small.
Treatment method: screw the adjusting pressure.
4. Under the sewing material, each needle appears in the wire sleeve, which is in the shape of towel wire sleeve
Analysis: feeding and stitching do not match.
Processing method: adjust the CAM screw to make the feeding consistent with the stitching action.
Machine maintenance failure (4) broken needle failure
1. Thick seam broken needle
Analysis: the machine needle is too thin or curved, the seam material thickness is not uniform, the needle bar moves too big.
Treatment: replace the thick needle, adjust to slow down the seam speed and use hand to help feed, replace the needle bar or needle bar sleeve.
2. Short stitch length is continuous, long stitch length is broken
Analysis: the motion of cloth feeding is delayed, the cloth feeding is unqualified, the machine needle hits the back end of cloth feeding and breaks the needle.
Processing methods: the positioning of the cloth CAM should be adjusted, and the needle distance should be shortened or the new feed tooth should be replaced.
The machine needle breaks under the needle plate
Analysis: the position of machine needle is low, the machine needle touches the pendulum hook, the machine bed is not installed properly, the needle is touched by the needle tip, the gap between the two sides of the needle end is too small or too large, and the needle is touched by the needle on the pendulum.
Treatment: adjust the position of needle bar or needle, reinstall the swing shuttle, and adjust the gap between the end of the swing shuttle holder and the needle.
The machine needle breaks on the needle plate
Analysis: excessive hand-holding sewing material, resulting in bending machine needle, loose presser foot screw, resulting in bending foot press needle, feeding CAM displacement caused stitching pulling machine needle, hard material in stitching material to make machine needle break.
Treatment method: strengthen the operation exercise, adjust the positive pressure foot to tighten the screw, adjust the position of the CAM screw.
Sewing machine maintenance fault (v) broken line problem
1. The first needle is broken, and the end is cut.
Analysis: the machine needle was reassembled or the machine needle was not fully loaded, causing the machine needle to be too low. The sewing material is hard, the machine needle is thin or the pressure of presser foot is too high.
Treatment: check whether the needle installation and needle bar connecting shaft screw are loose. Change the needle or adjust the pressure of the presser foot.
2. The suture is curled at both ends of the broken head with short whiskers.
Analysis: the clamping thread is too tight or the thread is twisted during sewing. The sewing thread is pushed into the guide slot of the shuttle bed by the swing shuttle. Suture is brittle and easily knotted, with poor quality and burrs at the crossing.
Processing method: replace the pressure of the clip and check the line to remove the mixed winding. Check the wear of the swing shuttle and replace it if necessary. Sand over the line, replace the suture.
3. The lower part of the seam is heavy with lines, which cannot form stitching distance and break the line. The broken line is ponytail.
Analysis: the feeding tooth is too low, and the seam will stop excessive and break. The feed is out of step with the wire. Press the foot, the machine needle loose, obstruct the seam running.
Processing methods: raising the feeding teeth, adjusting the positioning Angle of the feeding CAM, fastening the presser foot and machine screw.
4. The sewing thread suddenly broke and the surface thread curved and undulated.
Analysis: the position of the shuttle bed is not equipped with surface line and rolled into the shuttle bed. A sudden shift in the end of the spindle sleeve or in sewing. Poor bobbin quality bobbin heart spring is too long or elliptical sleeve.
Treatment: readjust the position of the shuttle-bed, reinstall the shuttles, and replace the swinging shuttles with a sleeve.
5. A sudden break in the sewing thread. Bobbin sleeve is not up to standard.
Analysis: the bobbin sleeve is unqualified, the diameter is elliptical, causing the bobbin rotation failure. The bobbin spring screw is too tight, making the bobbin pressure too small. The bobbin is too full or loosely wound. The bottom line is brittle and has a knotted head, preventing the bottom core from passing through the bobbin spring.
Treatment: replace the bobbin sleeve, loosen the bobbin spring screw, rewind the bobbin thread, and replace the bobbin thread.
Sewing machine maintenance failure (6) jumper problem
1. The bottom line cannot be drawn.
Analysis: the shuttle wire is too short, the shuttle wire is clamped to the shuttle door, the machine needle is too high, the pendulum wire can not catch the loop.
Treatment: elongate the bobbin, check if the bobbin is stuck, and remove it. Needle bar connection shaft screw loose needle bar move up, should be lowered needle bar, needle re-alignment, screw tight screw.
2. Needle bar hopping.
Analysis: pin hole, needle bar wear, needle bar attachment screw loose, needle bar displacement.
Treatment: replace the needle bar sleeve, or choose new needle bar, re-alignment; And screw the screw tightly.
Skip a stitch over several stitches.
Analysis: pendulum wear, too blunt tip, too high or too low needle.
Treatment: change the bobbin, adjust the height of needle bar or needle height, and adjust the needle again.
4. Do not sew a continuous jumper or a stitch.
Analysis: poor quality of needle or bending of needle can not produce thread ring. Machine needle is too high, can not hook the loop, sewing material sewing machine needle three improper coordination. Long - term use of swing shuttle, swing bed and other parts wear or break.
Treatment: replace qualified needle or straightening needle. Adjust needle bar or needle height. Under normal circumstances, the swing shuttle or shuttle bed can be replaced and overhauled if necessary.
5. Thin seam not jumpers, thick seam jumpers.
Analysis: the pressure of presser foot is not enough, the machine needle is too thin, and the parts such as wire drawing mechanism wear seriously.
Treatment method: adjust the pressure of the presser foot, change the needle, change parts, and repair.
6. Thick seam jumper and thin seam jumper.
Analysis: the needle holes of the needle plate are too worn, the machine needle is too thick, the bottom of the presser foot is worn, or the presser foot pressure is too small.
Treatment: change pin plate, change pin, change pin, change pin, or adjust pressure.
