The structures of causes of weak twist in fine yarns have the following characteristics:

(1) During the weft insertion, the canister and the steel reed can be fixed, and the weft insertion mechanism and the canister can be separated to accommodate high speed.

(2) The machine base can stay behind the shed for a long time, creating favorable conditions for high speed and wide width, while making full use of the height of the shed and reducing the stroke of beating.

(3) The cam, rotor and swing arm are all enclosed in the box, which can realize oil bath lubrication. The oil film that forms between the casual pair also mitigates the impact between the rotor and cam caused by beating. And can make multiple cam boxes work synchronously.

(4) The finishing and assembly precision of the cam is very high. The conjugation accuracy between the cam and the rotor should be controlled between 0.02 and 0.03mm, and the cost of the structure of the cam causes of weak twist in fine yarns is relatively high.

(5) The load of the flapping cam is relatively large, and its pressure angle should not be large, usually less than 30°, to reduce impact wear, and the pressure angle of the auxiliary cam can be appropriately relaxed. In general, cam causes of weak twist in fine yarns structures are characterized by short idle time of the carriage, long static time, high acceleration, and easy vibration of the mechanism. From the perspective of reducing vibration, it is better to reduce the stroke of the carriage, but when the size of the weft frame is constant, the stroke of the carriage is small, the opening stroke will increase, and the stroke difference between the two will increase. big. The front and rear healds are also very large, which increases the difference in warp tension, makes the warp easy to break, and makes the weaving fell jump up and down, so the stroke of the quilt cannot be too small, and it needs to be determined. On the other hand, according to the technical characteristics of various fabrics, the design And it is very important to choose the appropriate seam motion and formulate the motion law under the premise of meeting the technical requirements.

Sley's law of leisure should satisfy the following points:

(1) The acceleration of sley should gradually change from static to leisure, and from leisure to static, and there is no sudden change.

(2) The acceleration of the vibrator when flapping should ensure that the inertial force of the vibrator is greater than the flapping resistance.

(3) During the rest of the time, the acceleration curve should be continuous, the change should be gentle, and the peak should be small. For the above points, one leisure curve equation cannot satisfy all the requirements at the same time. Usually two or three types of curves are used in combination. The more commonly used one is the combined acceleration curve of sine and cosine, and the other is the improved trapezoidal acceleration curve.

causes of weak twist in fine yarns https://www.newheli.com/The-difference-between-twisting-and-false-twisting-in-textile-machines.html