The purpose of this study is to estimate the drafting force from the tension-strain curve of sliver. The tension-strain curve of sliver is generally shown in Figure 5, in which the tension increases to the maximum value and then decreases gradually. The typical relation between average steady state drafting force and draft ratio for sliver is shown in Figure 7.The drafting force also increases with draft ratio to the maximum value, then decreases. These curves are similar and can be divided into two regions. The first region, associated with increasing force at low strain or low draft, is characterized by fiber straighten-ing and uncrimping.The second region, with decreasing force, is relative sliding of fiber past one another. For the tensile and drafting behavior the increase of strain in the first region (Equation 1, 4) and the decrease of total contact length in the second region (Equation 8, 11) are respectively derived as a function of time. Assuming that the forces are equivalent when strain or total contact length is equal independent of the deformation mode, the drafting force is estimated from the tension-strain curve of sliver. For real three slivers the experimental results show close agreement with the estimated values.

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In previous paper, measuring needle temperature and sewing thread damage due toneedle temperature, in dynamic high speed sewing, have been discussed, and were mainly reported that needle temperature rises to a high degree and consiquently sewing thread damage is extremely large. In this case, it is necess-ary to obtain the acknolegements on the energy which is convertible into needle temperature. And in this paper, the diagram of the penetrating force of the sewing machine needle through fabrics (polypropylene film) is discussed.
The results obtained as follows.
(1) The diagram of the penetrating force of the needle culculated from the equations (5) ', (6) ', (9) 'and (7) agrees well with the measured ones.
(2) The penetrating force takes the maximum value at l=b, here, l is the interpenetrated length of the needle from the surface of the fabric and b is the height of the circular cone on the pointed head of the needle.
(3) The force K, acting on the needle part buried in the fabric in the perpendicular direction to the axis of the needle, increases linearly in the region l<b and decreases gradually in the region l>b.
(4) On the phenomena during extremely short time in case of penetrating of needle through fabrics, It is thinkable that the stress of fabrics takes no account of the relaxation. And, the curves of l-K take a superposition regardless of machine speed.

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In order to modernize patterning works of figured cloth by jacquard loom, a prototype of DDC weaving system for figured cloth has been developed. The system is consisted of the following equipments.
1. Pattern Analyser, 2 . Paper Tape Reader 3 . Mini Computer, 4 . Actuator for Selecting Needles of a Jacquard Machine, 5 . Jacquard Loom
The signal processing and weaving in the system are performed as follows :
(1) Colors and patterns in a sketch design are recognized by the pattern analyser, conver-ted into color pattern signal at run length and then punched out on a paper tape.
(2) On weaving, color pattern signals read out from the sketch design are read into a mini computer and are converted into pattern weavingsignals, corresponding to on-off bit pattern of the pattern card, by a stored program.
(3) The signals are sent to the actuators by a request signal from the jacquard loom and needles of a jacquard machine are selected by the signal synchronously with cycle of the loom motion.
Thus, a figured cloth is automatically woven according to a sketch design. Since highly skil-lful craftmen's techniques for production of pattern cards can be stored as a program, it is easy to weave a highly complicated figured cloth only by changing a color pattern tape andby resetting a design of fabric. The performance of the prototype shows that it seems possible to realize labor-saving and speed-up of the patterning work of jacquard weaving process requiring many workers.

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A handy shuttle speed meter, consisted of two sets of photoelect Tic switch, has been developed. It might be useful to control the shuttle looms operating in weaving mills.
The main features of the handy shuttle speed meter are as follolAs :
1) the mean velocity of a shuttle can be ea-sily measured, and
2) the velocity can be obtained with in one percent in standard error, when two sets of switch are held one meter apart.

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