The starting time of the carding machine is early or late, which is closely related to the quality of the fabric. During the spinning process of the spinning frame, the semi-finished roving or sliver is drafted, twisted, and wound into a spinning machine. The combed sliver and the needle-carding machine combine the sliver, the needle row is drafted to improve the sliver structure, and the roving is further spun into spun yarn on the ring spinning frame, which is the main spinning machine. Special equipment for the textile industry on the winder.
As the last process of spinning and the first process of weaving, winding is the link between the past and the next.“bridge”Therefore, it occupies an important position in the textile field. The structure of the double twisting unit of the double twisting machine mainly includes the spindle braking device, the spindle part of the double twisting machine, the yarn winding device, and the special device of the double twisting unit. At the same time, it also has a great influence on the coordination of other movements of the quilt production line, so the opening time is one of the main items in the weaving process parameter variables.
When using an early opening harness, the curved axle crank is at the top center and behind. During beating up, the secondary weft shed has been opened quite large, and the upper and lower warp yarns have a large cross angle (as shown in Figure 6-3A). Therefore, the surrounding angle of the warp to the weft is also large.
In this way, when the carding machine beats the weft, the resistance of the warp to the weft is large, the movement of the inserted weft in the opposite direction is small, and the wefts are arranged closely. thick. This is suitable for making dense fabrics. However, due to the great influence of resistance in different beating-up work processes, the friction between warp and weft yarns is violent, which not only is easy to scrape fluff, but also has many broken ends.
After opening, the center body is usually quiet before fully bending the shank, in beating, crossing the end of the lower warp at a small angle (shown in Figure 6-3B). Since the warpage of the cohesion of the weft yarn is relatively small, the beating of the warpage resistance of the weft yarn is relatively small, so that after beating, the weft yarn is easy to backwash the back, and the appearance of the cloth dealer is sparse. However, in the beating process, due to the small resistance of the beating, the friction between the weft yarns is smaller, the yarn is easy to fluff, and the yarn breakage can be less.
The opening time is determined according to factors such as the variety of different fabrics, yarn conditions and weaving technical conditions. The determined principles are 1. Usually one or more openings are used for early plain weave, the fabric should use a higher density initial opening, low fabric tightness can be used in the opening, high weight fabrics are woven by Xinsui, and the opening time is early. Compared with the normal plain weave, the opening is more clear, the three jump weaving defects and the improvement of fabric flatness are more beneficial. 2. When weaving twill weave and satin weave, due to the low back opening method and the resistance of the beating work, it is advisable to use late opening weaving, so as to meet the requirements of enterprises to reduce warp breakage and improve the clarity of these lines.
image 3. When the yarn strength is low or the sizing quality is poor, the opening time can be extended to reduce end breaks. When determining the opening time, the coordination with the picking, beating and other movements should also be considered.
In production practice, when weaving plain weave fabrics, the opening time can be configured so that the distance between the steel and the weaving fell is approximately equal to the radius of the crankshaft (70 mm).