A Pattern making method was introduced for constructing flared skirts which flare increases towards the hem.Geometric shape model and drape model were made for the purpose. A model combined the side of circular truncated cone containing the case of the central angle of the development being larger than 2π was used forconstructing the shape model. In the part of the central angle larger than 2π, the base line of the cone was approximated by sine curve to describe the 3D shape. Using the model, an automatic pattern making method applicable to various cutting including spiral cutting was devised. A geometric drape model, which is derived from the post duckling shape of an elastic slender board, was made to illustrate the drape state. Some paper patterns by using different cutting methods were made, and constructed them experimentally. The present pattern making method is flexible, since it could reflect the measuring dimensions, the skirt height, number of parts, spiral angle, spreading and arranged colors as parameters. The drape model could represent the draped shape of a real flared skirt well by giving the number of nodes.

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In order to investigate tow spreading mechanism by the new pneumatic method reported in the previous paper, spreading test using hung cylinders in air flow and observation of air flow through an array of fixed cylinders were conducted. The mechanism of tow spreading was discussed by comparing the results of these two model tests with experimental results of tow spreading.
The following results were obtained :
The pneumatic spreading force Fp and the recovering force fp act on a filament in an air flow at the same time. The position of the running filament in the pneumatic treatment is determined by the balance of the two forces F_p and f_p. Force F_p is influenced by the distance between two filaments and air velocity, while force f_p is determined by sagged length, filament diameter and air velocity. All the relationships between spreading width and processing conditions found in the previous experiments can be explained on the basis of the discussion above.
Air within tow is presumed to flow along the circumferential filament surface without so much disturbance. Therefore the significant local variation in the moved distance of the filament at higher flow rate is due to the local variation in the easiness of opening within tow.

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Understanding of general mechanism of the needle thread tension and the movement of the needle thread drawn out of the tension disc during a stitch formation is indispensable for performance of an excellent sewing. We propose a new simultaneous measuring method of them in high speed sewing with an industrial singleneedlelockstitch sewing machine. Two detectors for measuring needle thread tension were installed between the left arm thread guard and the needle bar connecting the stud thread guard, and between the right arm thread guard and the bending thread guard, respectively. The needle thread tensions are detected by sensing the deflection of a cantilever beam using semi-conductor strain gages. A laser feed monitor, manufacturing by Keyence Co., Ltd., model FC-2000 was used for measuring needle thread movement. The sensor head was installed on the sewing machine being out of contact with the machine. Needle thread movement was measured by using a rotating ring which moved with the needle thread because it was impossible to measure the thread movement directly. The ring and the ring holder are made of acrylic plates. Silicon oil is slightly supplied between them to reduce frictional force. The ring has 20 mm in outer diameter and only 0.1 g of weight, so it seems to be possible to neglect inertia force of the ring. The tension waves and the movement wave are recorded simultaneously with the marker signals generated at the upper dead point of the needle bar.

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