Lockstitch Sewing machine can be divided into high-speed lockstitch sewing machine, middle-speed lockstitch sewing machine and Low speed lockstitch sewing machine. They sew 5,000 or so lines per minute, 3,500 or so, and 3,000 below. In addition, the Lockstitch sewing machine also has knife-type, double needle type, up and down comprehensive feeding type and automatic cutting line type.
① ordinary medium-speed Lockstitch sewing machine: The use of connecting rod pick line, shuttle Hook line, the way to send materials (Fig 2). Use the oil line of the fuel tank and lubricate it by hand. Usually used in small and medium factories. ② Ordinary high-speed lockstitch sewing machine: The use of connecting rod pick line, shuttle Hook line, the way to send materials. The machine generally uses the oil pump to feed, automatically presses the lubricating oil to each movement part, the excess oil absorbs back or the oneself flows back to the oil plate. Usually used in large factories.
③ with knife lockstitch sewing machine: On the right side of the needle with a cutting knife, you can sew and trim the edge of two processes at the same time. In the seam material does not need to cut the edge of the part, you can pull the knife out of the cutting. The distance between the cutter and the machine needle is in the range of 3.2~9.5mm.
④ double needle Lockstitch sewing machine: Equipped with two machine needles and two vertical spindle, can make two lines of parallel work (such as sewing zipper, etc.) in one operation completed. In sewing operations, any machine needle can be individually lifted out of sewing, so that the gap between the left and right corner will not produce a defect of the intersection of lines. The distance between the two needles has a variety of specifications within the 1.6~16mm range.
⑤ Upper and lower comprehensive feeding sewing machine: equipped with upper and lower two feeding mechanism (Fig 3), the feeding quantity can be individually adjusted. When adjusting symmetry, sewing material of any nature can prevent the dislocation and deformation of the upper and lower seams. Conversely, if the upper and lower feed volume regulation asymmetry, you can get the required upper and lower layers of the seam between the move or crease. ⑥ Automatic cutting Line sewing machine: Equipped with computer and control sewing speed, stop needle position, pull line, back seam, sewing start and end of the reinforcement, lifting the foot, shear line, etc. with automatic function of the device and electromagnetic clutch motor, can make a lot of auxiliary action automation, and can make the hands of the operator focus on the treatment of sewing materials, improve sewing efficiency.