[in Japanese]

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In this experiment the high speed polishing of glass was investigated. Firstly, acrylic resin was used as polishing plate, and the influence of polishing liquid was found. Then, the shellac polishing plate was used, and the relation between polishing conditions and the stock removal of glass was clarified. Finally, the wear of acrylic resin polishing plate was measured, and effects of polishing conditions were examined.

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At first, the detective method of grinding burn was studied. Next, many tests were performed in surface grinding to study the effect of grinding conditions on grinding burn. Finally, the nature of grinding burn was discussed from these experimental results.
The main results of experiments are as follows.
(1) The detective method of grinding burn by means of reflectional rate changes was employed successfully.
(2) It was recognised that the nature of grinding burn highly depended upon the maximum temperature θ_m at the work-wheel contact surface. On the other hand, the effect of heating time was recognised little.
(3) The critical occurring condition of grinding burn was given by the following equation.
θ_m≥const
Now, this constant value was about 500°C in surface grinding of SKH 4 A high-speed steel with A 80 NmV wheel.
(4) The effect of treated wheel (wax) on grinding burn was recognised little.

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It was shown in a previous paper that the temperature of needle had a tendency to exceed the melting point of synthetic sewing thread while the sewing machine was in high speed sewing operation. It is considered that the reduction of needle temperature in sewing operation is one of the means to make a high speed sewing operation with synthetic thread possible and that the improvement of needle quality is one of the means to reduce needle temperature in high speed sewing operation.
The purpose of the present paper is to examine experimentally the effect of the improvement of needle quality. The influences of surface roughness, materials and shapes of the needle upon the needle temperature are measured. The results of experiment are as follows :
(1) Rough surface needle raises its temperature higher than smooth surface needle.
(2) In rising ratio of temperature, copper-beryllium alloy needle shows about 30% less than steel needle.
(3) Triangular point needle shows the minimum rising of needle temperature among five kinds of needle points.
(4) The needle manufactured for trial shows the minimumrising of temperature among six kinds of needle shanks.

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In the process of manufacturing transistor, a lot of girls are engaged in its work. Especially in mount operation, almost all the works depend on their highly skilled handlings. It would, therefore, be quite efficient and economical if we could adopt automatic operation instead of their handlings.
To materialize this idea, however, there are much trouble. The structure of diminutive size and delicate articles made it difficult to handle mechanically. Besides we can expect no accurate dimension in the pitch of stem leads, for they are set by sintered glass. Under such difficult condition, we started the job to meet much trouble as was expected. But we are successful in mechanizing the works last year. As a result, we can save the operaters six or eight for two shifts without employing skilled girls to produce the transistor with uniform quality and characteristics.
This report covers the operation and mechanism concerning this machine in each stage of them and its own linear indexing mechanism.
Machine General
Transistor : Germanium Transistor used for low frequency. (Envelope TO-1)
Size : 2700 mm length × 820 mm width × 1400 mm height
Production : 1200 pieces/hour (or more)
Operator : Automatic (But two for parts preperation)

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