Due to the increasing popularity of Numerical Controlled Machine Tool Systems, the development of the higher level soft wares in this field becomes necessary. Further more, direct connection between Computer-Aided Design (CAD) and Computer-Aided Manufacturing brings about a problem.
In order to cope with these situations, this paper proposes a new method on the automatic programming for NC considering the connection of both systems.
After description of the workpiece profile by “Formulated Pattern” in the process of CAD, this method makes it possible to generate automatically NC commands for the tool path.
The basic idea of this method is to establish the penalty surface arround the workpiece profile as a guide for determining the tool path.
Since, using “Formulated Pattern”, the penalty can be given such as having minimum value on the cutting point, the problem for finding tool path is reduced to that for seeking minimum on the penalty surface.
In this paper a theoretical development of this principle and practical algorithm for the determination of tool path are described with two examples, NC milling of NASA Airfoil pat-tern and plate cam designed by CAD procedure. Then, a method for collision check using same principle is described too.

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Turning tests of high carbon steel (S 50 C) are undertaken with a cooled cutting tool in order to reduce the cutting temperature, and hence to improve the tool life. The tool is characterized by internally cooling with circulating liquid through a relatively simple refrigerator.
This paper presents the test results of turning in the cutting speed range of 20 to 250 m/min at -25° to -30° with high speed steel tool (SKH₄) and carbide tool (P 10).
The main results obtained are as follows :
(1) The tool wear can be reduced substantially by this cooling technique. Consequently, the tool life is increased as far as 1.2 to 2.6 times on flank wear and 1.2 to 3.8 times on crater wear as compared with those in the ordinary cutting.
(2) The temperature on the tool- chip contact interface reduced about 20° to 80°C in the cooled cutting tool.

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The object of this study is to improve precision and heavy grinding operations of 0.008-0.97%C steels by introducing hydrogen treatment (cathodic charging in 5 vol. % sulphic acid Aq.). And, the present paper deals with the effect of the hydrogen embrittlement in steels on grindability factors; that is normal and tangential grinding force F_n F_t, surface roughness, side flow of ground surface, damaged structure and residual stress in grinding layer.
The main results obtained by experiments are as follows :
1) The reduction of grinding force due to hydrogen embrittlement gives about F_n=30-45%, F_t= 25-35% in the range of 0.008-0.97%C.
2) The reduction of surface roughness H_max due to hydrogen embrittlement gives about 20-50% in the range of 0.008-0.97%C.
3) The reduction of side flow of ground surface due to hydrogen embrittlement increases gradually as carbon content in steels decreases.
4) The reduction of plastic flow in ground surface layer due to hydrogen embrittlement increases gradually as carbon content in steels decreases.
5) The dimensions of residual stress distribution in ground surface layer due to hydrogen embrittlement is not very much changed.

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The purpose of this study is showing the relation between drilling force, and its accuracy in the precision drilling of wood.
It is found that, by the result of analyzing the drill deflection curve occured by drilling force statically, the vertical angle θ of drilled hole is approximatelly equal to the tangential angle φ at the drill point which is descrived with axial force T acting at tip of the drill, ratio H/T between axial force T and radial force H, projecting length of drill l, Young's modulus E of drill material, and the moment of inertia I.
From the obtained equation, improving the accuracy of drilled hole, in a case of l, E, I=constant, it is found that reducing T and H/T can become the main factors. Reducing these main factors actually can be shown by using ultrasonically vibrated drill and it is also con-firmed that a concrete process of improving the vertical angle θ.

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The musical sound in each key of a cantilever-electro-piano is produced from the vibration of respective cantilever-top. But the sound is composed of many strong over-tones whose frequencies are integer multiples of their fundamental. The cause of the beats sensation of the sound in the bass section is explained in this paper. The beats appear in the harmonics, when (1) the vibration of the cantilever-top is a higher-order-beat oscillation, represented by the equation y=cos ωt+acos (nω+ε) t, where a is amplitude ratio, n is 79, and ω, ε (ω>>|ε|) are frequencies, and (2) the vibro-electro-trans-ducer is non-linear.

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