Air jet driving and supporting devices were tested for a high speed open-end spinning frame . Two types of rotors were prepared : the upper fluting rotor and the under fluting rotor. Each rotor was driven by air jet impinging upon the fluting directly from the nozzles prepared on the inner surfaces of a stator. The rotor was supported on its under conical surface by the dynamic pressure of air thrown down by the upper flutings or of the air jet itself on the under flutings. Series of tests were made for both types of the rotors, changing their conical angles, number and angle of the flutings, and driving air pressure. The results were as follows.
(1) The speed of rotor increased with increasing driving air pressure and reached the limit of speed quickly.
(2) The rotor conical angle 108°was suitable for the upper fluting mechanism, and 102°was suitable for the under fluting mechanism, with a fixed stator conical angle 92°.
(3) The number of flutings was suitable around 40 for the upper fluting mechanism, and 20 for the under fluting mechanism.
(4) The fluting angle influenced considerably to the driving torque, the fluting angle 45° and 25°was suitable respectively for the upper fluting and the under fluting mechanism.

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In the previous paper, an analysis was given of elastic component of the bending property of warp knit fabrics, considering the mechanical properties of yarns in the fabric to be perfectly elastic.
In this paper, the bending properties of some fabrics are measured using a pure bending tester designed by Kawabata and then the data are compared with the theoretical calculations. The results show that this theory has enough accuracy to estimate the property, but a little amount of error is observed for the high density fabrics having large number of underlapping.
On the base of microscopic observation, some discussions are done for a mechanism in the deformation of knitted structure during bending, proposed in previous paper.
It is another purpose of this paper to show how frictional restraint to the bending of the fabric arises. The frictional component is derived from the sum of the frictional resistances among fibers in the bending and twisting of constituent yarns and that between yarns in crossover region. This analysis is found to give a reasonably close prediction of it to the fabrics having loose structure.

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In textile industry, performance of the fabrics is still out of the engineering design, because of the difficulty in designing the proper mechanical properties of fabrics, and also of the difficulty in evaluating the performance where the evaluation has been done by a sensory method named “handfeel” by experts.
In this article, recent developments in the Hand Evaluation and Standardization Committee (Chairman Sueo Kawabata, The Text. Mach. Soc. of Japan) during three years are introduced.
The progress of the research is as following.
1. Definition of primary hand feeling for clothing fabrics.
2. Selection of the standard samples of hand feeling by 20 experts from textile industries in Japan.
3. Representation of hand by numerical value (H.V., 0-10).
4. Evaluation of H.V. by the experts for each of 1000 samples which were collected from many companies.
5. Researches on physical and mechanical properties of fabrics especially on characterization method of those “non-linear” properties. Each of tensile, bending, shearing, compressional and surface properties are represented by two or three characteristic values.
6. Mathematical and statistical analyses to join the experts' H.V. and the physical values.
7. Formulas to translate physical values to H.V. were obtained.
8. The following applications are introduced .
1) Application to the establishment of the formulas for calculating the total hand values from those primary hand values.
2) Analyses of the good quality fabric.
3) Application to the establishment of the formulas for calculating the hand values of knitted fabric for men's out wear.
4) Application of the formulas for hand calculation to the textured-knitted fabrics.
5) Application to the establishment of the formulas for calculating the hand values of silk fabric for Kimono.
6) Application to the process analisis in the textile mill, for example, the relation, between the finishing condition. and the hand of the fabrics finished, and the effect of the type of weaving machines such as shuttle loom, jet loom and rapier loom on the hand of the fabric produced by those.

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