Pneumatic Actuator used as a final control element of automatic control system, generally carries the residual deviation caused by change of axial load, even if it is equipped with a positioner.
In this paper, the main factors influencing the amount of residual deviation found in the spring balanced type diaphragm actuators are studied both from theoretical and experimental standpoints, and as its result, a semi-experimental equation shown in Eq. (12) is obtained.
Effective approaches to minimize the residual deviation are as follows:
(1) Sensitivity of positioner's pilot valve should be as high as possible within the stability range.
(2) The constant of balancing spring or the effective area of diaphragm should also be as large as possible.
(3) The larger feedback ratio of positioner, the smaller absolute value of residual deviation.
(4) The larger total operating lift of actuator, the smaller rate of residual deviation.

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Given in this paper is a nondestructive measurement of the quenching depth of steel. It is well known that the permeability of steel decreases remarkably in quenched sections. By the above reason, inductance of the search coil pressed upon the surface of a specimen varies with the quenching depth. An alternating current bridge is used to measure the inductance of the search coil. The balancing of the bridge is detected by amplifier and oscilloscope, and at the same time the resistance value of measuring arm is indicated directly by the scale of the quenching depth. For a cylindrical rod made of fixed material and having fixed diameter, satisfactory results were obtained. Further, the authors succeeded in the measurement, independent of diameter of the specimen, only by putting the specimen on a V-shaped magnetic plate. For different-material specimens, it seems to be the simplest way at present to change the scale. As to this problem, however, some better method is believed to be found in the near future.

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This is the device that records on X-Y recorder the waveforms or patterns of alternating current, which are usually observed by cathode ray oscillograph. For recording on X-Y recorder, an instant value at an arbitrary phase has to be taken as a direct current value. For this purpose, the author differentiates the original waveform and then integrates it from t0 to t',
If one selects t0 that makes f(t₀)=0, this integrated value represents the instant value at t'. The linear gate that determines the integrating interval is required high accuracy. This gate is all constructed by transistor circuit, but by using complementary symmetry circuits and negative feedback, sufficient accuracy was achieved. The gating signal that controls the linear gate is also generated from transistor circuit. As an example of operation, recording of a.c. B-H curve and curve of the transistor characteristic driven by a.c. signal is shown.

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硫安と硝安の飽和槽内中和反応のpH制御の実施例につき,MONSANT CHEMICAL Co.,よりアメリカ計測学会INSTRUMENTAL METHODS OF ANALYSIS大会に1957年6月報告された論文である.硫安飽和槽のpH制御,硝安中和反応槽のpH制御の2章にわけ,高温用ガラス電極によるpH制御を行った実施例を示す.

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