The Main Mechanism and Working Principle of Warp Knitting Machine

1. Introduction of warp knitting machine

Knitted fabric is formed by looping one or several groups of yarns arranged in parallel on all working needles of the warp feeding machine. This method is called warp knitting, the fabric is called warp knitting, and the machine that completes this warp knitting is called warp knitting machine. It is commonly used to knit warp knitted fabrics with complicated organizational structures such as curtains, tablecloths, bedspreads, blankets, lace ribbons, fishing nets, etc.

2. Main institutions of warp knitting machine

Warp knitting machine is mainly composed of knitting mechanism, guide bar traversing mechanism, let-off mechanism, drawing and coiling mechanism and transmission mechanism.

3. Working principle of warp knitting machine

① Knitting mechanism includes needle bed, guide bar, sinker bed and pressing plate, which are generally driven by cam or eccentric connecting rod. Cam is often used in warp knitting machines with low speed and complicated motion law of looping parts. Eccentric connecting rod is widely used in high-speed warp knitting machine because of its smooth transmission, simple processing and low wear and noise during high-speed operation.

② Guide bar traversing mechanism, which makes the guide bar traverse according to the requirements of knitted fabric structure in the process of looping, and pads the warp on the needles, so as to weave knitted fabric with a certain structure. There are usually two types: flower plate type and cam type. Pattern mechanism connects patterns with patterns of a certain shape and size in series to form pattern chains according to the requirements of knitted fabrics, so that the guide bar moves transversely. It is suitable for fabrics with complicated knitting patterns, and the pattern change is convenient. In the cam mechanism, the cam is designed according to the traverse rule of the guide bar required by knitted fabric organization, and the transmission is stable, which can adapt to higher knitting speed.

③ Let-off mechanism, which disengages the warp on the warp beam and sends it to the knitting area. There are two types: negative and positive. The negative mechanism, in which the warp beam is pulled by the warp tension to send out the warp, does not need a special warp beam transmission device, and is suitable for warp knitting machines with low speed and complicated let-off rules. Active let-off mechanism adopts special transmission device to make the warp beam rotate and send out warp, and there are tension induction type and linear speed induction type. The tension mechanism controls the rotation speed of the warp beam by inducing the warp tension by the tension bar. The linear speed induction mechanism controls the rotation speed of the warp beam by sensing the warp movement speed by the speed measuring device. This kind of mechanism sends out warp yarns at a predetermined linear speed, and can work stably under high-speed running conditions, so it is widely used in high-speed warp knitting machines.

④ The function of the drawing and winding mechanism is to draw the fabric out of the knitting area at a predetermined speed and wind it into a cloth roll.