This article gives an account of theoretical treatment of the function of the flyer presser. It points out that the main factor which generates the presure of the presser is the moment produced around the central axis of the hollowleg by the deviation of the position of the gravity center in the presser; and that the character of the position of contact between the presser paddle and the sliver bobbin differs in the two parts.
The pressure of the presser on the sliver bobbin during winding is obtainable by balancing those moments around the central axis of the hollowleg which result from reaction force, frictional force, roving tension and air resistance acting on the presser. We call this pressure the “winding pressure of the presser, ” as distinguished from the commonly used presser pressure which does not take the frictional force and roving tension into account.
An analysis of the pressure of the presser has made it clear that _??_ value as to the shape of the presser must be determined from 140°_??_165° after consideration of various conditions; that three types of pressure of presser [descendant, ascendant and almost constant corresponding to θ or γ] are obtainable by α value; and that these gradients can be changed at will.
The pressure of various types of flyer pressers has been examined. The date obtained from the examination have shown that the magnitude of the pressure of the presser can be classified according to the type of the flyer frame; and that the gradient of the pressure curve depends upon wa as well as α and _??_.

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It is difficult to decide experimentally how best to arrange the numerous holes to be made on the spinneret of acetate dry spinning. As a method of theoretical inquiry, we attempt to determine the suitability of the arrangement of holes by using a purely geometrical and practical parameter which is useful for expressing the degree of inter-hole obstruction of evaporation. A comparison of calculated results with experiments showed no contradiction.
We believe this mathematical treatment suggest a way for deducing the best arrangement of the holes on an acetate spinneret.

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The author sought to establish the relations among the structural designs of weaving, the drawn-in darft, the treadling and the cording plan for warp lifting by means of the multiplication of matrices.
If such matrices are used as the elements consist of the marks of the lifting plan, it has been possible to clarify mathematically the relations among those items above mentioned, and to simplify the drawing of the lifting plan without the sacrifice of accuracy.

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An attempt has been made to represent the crease recovery angle in any direction as a function of values in the warp and weft. The results of this attempt make possible to estimate the degree of interaction between warp and weft yarns at the points of their intersection.
The crease recovery angle along any direction of a textile fabric is described as follows:
β=1/sinθ+cosθ(β_W sinθ+β_F cos θ)
β_W=cos^-1{(1-cosω_W)cot²θ-cosω_W}
β_F=cos^-1{(1-cosω_F)tan²θ-cosω_F}
ω_W=AW 2θ/π.ω_F=A_F(π-2θ)/π
where, θ is the angle between crease line and the warp yarn; (π-A_W) and (π-A_F) are the crease recovery angles of warp and weft, respectively. In fabrics composed of loosely crossed yarns, good agreement with experimental data is obtainable.
It is helpful to use the degree of deviation between theoretical and experimental data as a measure of the tightness of fabrics. There are comparable relations between anisotropy of crease recovery and flexural rigidity of textile fabrics.

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Object of study:
Sucking nozzles which exhaust fly and dust in spinning mills usually expand at the throat. It is, therefore, necessary to get the proper expansion angle so that a nozzle may do uniform sucking on a plain covering a wide scope.
In a previous article (Part 1) we dealt theoretically with the characteristics of suction nozzles. In the present article we establish, by experiment, the reasonableness of our previous researches and make clear, empirically, the sucking characteristics of finned and pipy nozzles.
Main points of the present article:
1. The relation between the expansion angle of a nozzle and its sucking performance has been experimentally inquired into and experimental results obtained show that the best uniformity of sucking performance is obtainable from:
a) Slightly reduced rate of air flow
b) An expansion angle less than 60°
c) An expansion angle less than 30° at the throat of a circular nozzle.
2. The sucking characteristics of finned, finless and pipy nozzles have been clarified experimentally and date on designing them obtained.

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