A heavy sliver has been experimentally produced by using a carding machine of which the cylinder was equipped with a metallic wire and the doffer with a wire fillet card clothing. The relation between the sliver weight and the acting angle of the wire fillet card clothing on the doffer has been investigated for acting angles of 76°, 65°, 53° and 40°.
I. The case of increasing the fiber density of the doffer with a constant sliver production, 6 kg/hr.
1) The number of neps in the sliver that was obtained with the acting angles of 65°, 53°and 40°, remained unchanged compared with the number of neps in the sliver at the standard condition, within the limit of the fiber density of the doffer, 5, 40 and 80 g/m², respectively.
2) The coefficient of variations in the sliver weight decreased with an increase in the fiber density of the doffer.
3) The higher the fiber density of the doffer, the larger the difference due to the combing direction in the orientation index and the combing ratio.
II . Increasing sliver production and fiber density of the doffer with a constant number of revolutions of the doffer.
1) With acting angle of 65°, 53° or 40°, the number of neps in the sliver increased as the increasing fiber density of the doffer and the acting angle increased.
2) The coefficient of variations in the sliver weight decreased as the fiber density of the doffer increased.
3) The combing ratio of the sliver increased with an increase in the fiber density of the doffer, but the orientation index remained unchanged.

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We have microscopically examined fabrics broken to pieces by abrasion, and then investigated qualitatively the process of breakage of fibers. We have reached the following conclusions.
(1) The mechanism of abrasion by emery paper.
(a) When fibers can be embedded among the particles of emery paper, the abrasion of fabrics is mainly caused by hooking up.
(b) When fibers cannot be embedded among the particles of emery paper, the abrasion of fabrics is mainly caused by scratching. In synthetic fibers, thermal breakage may occur with an increase in contact pressure and speed.
(2) The mechanism of abrasion by steel blade. When the contact pressure is high, the abrasion of fabrics is mainly caused by hooking up.
(3) The mechanism of abrasion by steel plate.
The abrasion of fabrics is mainly caused by the accumulation of microwearing off, and final breakage of fibers is due to axial tensile stress produced caused by frictional force between fabrics and abradant.

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The control mechanism of the electronic universal testing machine for measuring the minute expand and contract loads or extensions of materials such as “Mechano-chemical system”, which is varied with some physio-chemical treatments, are analyzed and discussed.
1) When a self expansion and contraction is interposed as disturbance of this control system under load input type, the self expand and contract deformation of test pieces can be tested faithfuly with this tester.
2) Under extension input, the self expand and contract load of test pieces can be tested precisely.
3) From the experimental result, the transfer function of “Mechano-chemical system”, expanded or contracted with pH or temperature of soap solution, is shown as follows.
G_MP(s)=K_ph/(T_Prs+1)(T_DcS+1)≈K_ph/(T_Prs+1)
Where T_Pr : time constant of permeability
T_Dc : time constant of dissociation
G_MH(s)=K_He/(T_Cos+1)(T_Mcs+1)
Where T_Co : time constant of heat transmission
T_Mc : time constant of molecular movement
4) We found from the results of the test that “Mechano-chemical system” is perfectly adequate as a transduser to convert the consistency of solution (in this case pH) into a change in electric voltage.

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A universal electronic testing machine has been experimentally produced and the characteristic of its control system has been analyzed with respect to the effect of nonlinear properties of transfer elements on the stability of the system.
When the input signal is sinusoidal, there is no output signal produced if the input amplitude falls in the backlash zone, but when the input signal contains some random noise in it, the stable regions are changed.
(1) When κ₁ is assumed the equivalent gain of the neutral zone for the sinusoidal input, a formula
κ₁=(T_A+T_M)[-(T²_A+T²_M)+√D]/k[(T_A+T_M)²-√D]T_AT_M
is obtained where
D=(T²_A-T²_M)+4(T_AT_M)²(T_A+T_M)K
(1) The proportional gain K of the linear part is included in the denominator and numerator of the above formula. As a result, the increase of K value results in the increase of κ₁. So that, the increase of K extends the stable region for both sinusoidal input and radom input. In other words, the increase of K has the same effect on the stability of the system as the increase of (Az/a).
(2) Decreasing of variance σ²n of the random noise extends the stable region.
(3) Above conclusions lead us to the next method for increasing the stability of the system.
When the value of Az/a is large and the proportional gain K is fixed, it is recommended to place a saturation element in front of the neutral zone, and provide a filter to reduce the value of σz/a.

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