A laboratory apparatus has specially been designed to investigate the feed length of upper and lower fabrics, the pick up tension of these fabrics caused by a feeding motion of the feed dog and pressure of the presser foot for a household sewing machine in a sewing operation without sewing threads.
The experiments for fabric feeding were carried out under a fixed crank shaft speed of 4 rpm with six kinds of fabrics having different factors such as thickness and fabric structure. Moreover, in order to vary the frictional force between upper fabric and presser foot surfaces and that between lower fabric and feed dog surfaces, three kinds of presser feet and two kinds of feed dogs which were made of different materials, were used in the experiments.
Experimental results have shown that, to feed fabrics without troubles, it is necessary (1) to lower the frictional force between an upper fabric and a presser foot, (2) to enhance the frictional force between a lower fabric and a feed dog, and (3) to make pressure of a presser foot to a minimum as possible.

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A study has been made by the reeling of directly dried silk yarns to manufacture the softly wound cheeses to be directly lubricated. This enables the labour-saving in the yarn manufacturing and weaving preparatory process eliminating the silk reeling. The following results are obtained :
(1) An extremely soft cheese winding of raw silk without yarn sticking or package deformation has been achieved by drying completely wet bundle assembles while reeling. The soft cheese thus obtained can be directly processed by lubricating, soaking or similar processing. Consequently, it can extremely save labours in a subsequent weaving preparatory process.
(2) The raw silk of soft wound cheese is even in quality and formation and is excellent in physical properties in comparison with skein yarns.
(3) The cheese winding by a reeling of a directly dried silk yarns can contribute to the labour-saving in the cocoon reeling process, eliminating the rereeling and finish bunding process.

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A micro computer unit for a lappet loom has been developed to control both the revolving angle of a servomotor and the on-off motion of solenoids . The one actuates the lateral movement of the lappet figuring needle-frame. The other actuates the vertical motion device for spot figuring, the box motion and the dobby apparatus in an ordinary lappet loom. The figuring unit thus constructed made the width of lappet figures very larger, the height longer and the intervals of spot figures more variable. Moreover, the dobby weaves and the weft mixing effect got more diversified . By this lappet loom, therefore, highly fashionable products could be manufactured.

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To improve the dimensional stability of figured crepe fabrics made of hard plied yarns, the mechanisms havebeen investigated of warp and weft-wise shrinkage and extension caused by performances of hard twist yarns, designing, weaving, degumming and finishing conditions. The following fundamental empirical equations have been derived.
(1) A warp-wise shrinkage caused by weaving and degumming is proportional to K₁ for flat woven crepe fabrics and to K_c for figured weft double crepe fabrics.
(2) A weft-wise shrinkage is expressed by :
f (s) =a₁ (M. T. C.) /K₂, for flat woven crepe fabrics, and
f (s) = (1.730×10^-4×M. T. C.-0.2K₁+5.91) /K_f,
for figured weft double crepe fabrics,
where,
α₁ : experimental constant depending on the fabric construction,
K₁ and K₂ : cover factors of flat woven crepe fabrics at warp and weft-wise direction respectively,
K_c and K_f : cover factors of figured weft double crepe fabrics at warp-and weft-wise direction respectively, and
M. T. C. : Multi-play Twist Coefficient.

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In this paper, the effects of solvents are reported on the swelling and the diffusion properties of acrylic fibers. The degree of swelling correlates with the solubility parameter (δ) of the solvents. Maximum swelling occurs with solvents whose solubility parameter approaches that of acrylic fibers, 12.98cal^0.5/cm^1.5.
Supposing T₁ as a parameter of the starting temperature of a shrinkage, T₁ becomes minimum with solvents whose solubility parameters are similar to that of acrylic fibers. The coefficient of diffusion correlates with T₁, and increases with decreasing T₁ of the fibers.

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Photographic pictures have been taken of thread looping of an industrial sewing machine using three kinds of presser feet and six kinds of fabrics to investigate how the shapes of presser feet and the loop guard affect thread looping.
The pictures have shown that :
(1) A form of typical loop with the loop guard conforms to a lemniscate inclined by about 13°to the scarf side of the needle.
(2) The width of typical loop (Y_g) with the loop guard is given by :
Y_g_??_Y+d·tan13°
where,
Y : the width of a typical loop without the loop guard, and
d₀ : the distance from the lowerside of a throat plate to the meeting point of a shuttle hook.
(3) The flagging, which causes the skipping stitches, can be prevented by using a proper shape of presser foot that press fabrics down tightly, even when the sewed fabrics tend to flag.

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