Design And Optimization Of The Pure Pneumatic Tuck-in Selvedge Device Used On Loom

With the vigorous development of the textile industry and the continuous improvement of people’s living standards, the market demand on the quality of tuck-in selvedge is also rising. The pure pneumatic tuck-in selvedge device is one kind of the pneumatic device used on shuttleless loom to forming a neat selvedge, its performance directly influences the fabric quality, and it also has great influence on the subsequent stages of manufacture. Pure pneumatic tuck-in selvedge is a kind of advanced technology in textile field for producing neat selvedge, which uses compressed air by griping the end of weft than folding it into the weaving opening, and finally achieve a neat selvedge. The effect of pure pneumatic tuck-in selvedge device has significant influence on the production quality and production cost of close, and it mainly determined by the parameters such as the length of weft’s extra end, kind of yarns and folding jet orifice geometrical.At first, the importance of the process folding the extra weft for shuttleless loom is expounded. By comparing the domestic and foreign research status, the significance of the research and development of pure pneumatic tuck-in selvedge device is put forward.Next, based on the working principle of pure pneumatic tuck-in selvedge, this paper puts up a optimized design plan of pure pneumatic tuck-in selvedge device can be used folding the the extra weft into the weaving opening, and the length of weft’s extra end is less than 8mm. Than the grid division of the flow fields of different structure parameters of pure pneumatic tuck-in selvedge device is completed after 3D geometric modeling, and the flow fields are analyzed by using the CFD method. By changing the geometrical parameter of the folding jet orifice structural parameters and comparing the dynamic distribution of their velocity field to explore the effect and mechanism of air flow on folding the weft’s extra weft, in this way we also can analyse the effect of folding jet orifice geometrical on the efficiency of this device. The rational parameters is obtained as follows: the spacing of the two group of folding jet orifices f = 3 mm, the spacing of the folding jet orifices in each group e = 3 mm, the spacing of each group of folding jet orifices and the bottom of the Y type yarn guiding port d = 7.5 mm.Once more, choosing Omron PLC and touch screen as the control core of pure pneumatic tuck-in selvedge device, according to the demand of full automatic control and single cycle automatic control, this paper designs the ladder diagram program to achieve this device’s automatic control and human-computer interaction.At last, in the school laboratory the pure pneumatic tuck-in selvedge device is used in the test folding single weft’s extra end into the weaving opening. By testing the different devices,which have different geometrical parameter of the folding jet orifice structural parameters, to verify the authenticity of numerical simulation. And the rational pure pneumatic tuck-in selvedge device is used in the test folding the weft’s extra end, which have different length or bending rigidity, into the weaving opening. By comparing the result of different tests to verify the optimized effect of the pure pneumatic tuck-in selvedge device.