This paper describes on-line feedback control techniques for regulating the area density distribution in low-density air-laid nonwoven webs in both the machine direction and the cross-machine direction. The web area density is monitored in real-time by a scanned-laser-based device. The web density distribution along the machine direction is regulated by controlling the transporting belt while the web density distribution in the cross-machine direction is regulated by a vane system in the suction chamber.

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This paper presents a new approach to wool sliver cleanliness analysis based on computer image processing system. The characteristics and principles of the instrument will be described in detail. Then, the validity of the system is investigated by comparing a significant number of cleanliness measurements carried out by this system and visual method judged by skilled specialists.
The results of this research show that there are no significant differences between detected defects such as fibrous defects or neps and vegetable matters by this system, and visual method exception in case of small size neps. A discussion of these results will be presented in this paper.

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For a rapier designed to control the yarn inserting motion from the start of the motion to its end, a servo-controlled weft yarn inserting mechanism designed to allow the weft yarn inserting motion characteristics to be changed was developed to study experimentally the effects of the weft yarn motion characteristics on the weft yarn tension.
In the experimental study, this mechanism was used in the rapier loom to insert weft yarn with its inserting motion characteristics changed to measure its tension accordingly changed. The results of the measurement showed that the weft yarn tension is significantly affected by the weft yarn inserting motion characteristics. Then, to clarify the relationship between the weft yarn tension and the weft yarn inserting motion characteristics, a weft yarn tension model was made for simulation. The results of the simulation were in good agreement with those of the experiment, providing theoretical explanation about the relationship between both.
The above suggested that the servo-controlled weft yarn inserting mechanism is very useful for a rapier loom in terms of its allowing the weft yarn inserting motion to be changed properly according to the weft yarn to be used.

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In this report influ ence of the compounding ratio of sintering annex, MoS₂ and FeMn porous sintered metal ring wasexamined for the purpose to improve abrasion character of spinning rings. 5 classes of the compounding ratio are adopted for the laboratory abrasion test to clear up the relations among the accumurate wear, the surface roughness and the fluid permeability of the ring. Experimental results showed that the compounding ratio of annex MoS₂ equal to 60-67% gave better character than the others as a whole. The practical abrasion test was carried for the developed ring (MoS₂ 66.7% and FeMn 33.3%) and was compared with that of standard ring (MoS₂100%). The test proved the superiority of the former over the latter and the superiority on abrasion character of the developed ring was due to excelence of the pores state of the ring to lubricate its surface.

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