老式脚踏缝纫机故障维修（Old foot sewing machine troubleshooting）.docVIP

老式脚踏缝纫机故障维修（Old foot sewing machine troubleshooting） Old sewing machine trouble shooting I. jumper 1, fault features: can not lead to the bottom line. The product line is too short, the shuttle shuttle clamp in door, the needle is too high, the shuttle can not hook line ring. How to handle: lengthen the shuttle line, check whether the bottom line is jammed and exclude it. The connecting rod of the needle rod is firm and the screws are loose. The needle rod should move upwards. The needle bar shall be lowered, and the fastening screws shall be tightened again. 2, fault characteristics: needle rod moving. Product reasons: needle rod hole, needle rod wear, needle rod connection screw loose, needle rod displacement. Methods: to replace the needle bar sleeve, or optional needle rod, to tighten the screws and pins. 3, fault features: a few needles, jump a needle and thread. Product: swing spindle wear, spindle tip is too blunt, sewing machine needle is too high or too low. Processing method: swing the shuttle, adjust the height of the needle bar or the needle height, re stitch. 4, fault features: continuous jumper or stitch can not sew. Product reasons: poor quality of machine needle or machine needle bending can not produce thread ring. Sewing machine needle is too high, can not hook the wire ring, sewing material, sewing machine needle three improper coordination. Long term use of swing, swing, bed and other parts seriously wear or fold. Treatment method: replace the qualified machine needle or straightening machine needle. Adjust the height of the needle bar or sewing machine needle. In general, shuttle or shuttle beds can be replaced and overhauled if necessary. 5, fault features: thin seam, no jumper, seam thickness jumper. Product reasons: presser foot pressure is not enough, sewing machine needle is too fine, tick wire mechanism and other parts of serious wear and tear. Processing method: adjust the foot pressure, replacement needle, replacement parts, repair. 6, f