The present paper deals with the formulas to calculate the pitch diameters or the measurements over wires of the Archimedean worm thread screw and the involute worm thread screw, which have one or multi-start threads and large lead angles, in measuring screw threads by the three-wire method. Furthermore the best wire diameters which contact in the pitch diameter of worm, and the smallest wire diameters to provide the measurements over wires equal to the major diameter of an external thread are calculated. The approximate formula to calculate the pitch diameter of the Archimedean worm thread screw with high accuracy without using the method of successive approximations is obtained, and the accuracy of the approximate formula is discussed. The theoretical formula to calculate the measurements over wires of the involute worm thread screw is derived, and the equation to calculate the tooth thickness of the involute worm threads from the measurements over wires is obtained.

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The purpose of the present investigation is to clarify individual differences in subjective roughness comparison task. To analyzing individual differences in point of relationship between physical and sensory measurements, the multidimentional paired comparison model is proposed. Using the model, data which were obtained through the following experiment were analyzed. The experiment was designed for investigation of correspondence between both measurements. 18 Test pieces (BsBM) with turned surfaces were prepared in which R_rms, mean spacing of profile irregularity peaks, W_EA and radius of profile peaks were factorially combined. Seven skilled labors in an optical industry were served as subjects in Experiment. By the model analysis, individual differences are obtained and represented in the profile patterns. For testing the validity of the model, Carroll-Chang's internal vector model analysis of same data was carried out. As results, the individual differences were described as vectors in a multidimen-sional feature space. Configuration of Eigen vectors (test pieces) derived from the internal vector model analysis are clearly shown that principal physical characteristics which affected the human judgment are R_rms and mean spacing of profile irregularity peaks. Relation between both models are discussed. Practical aspects of the findings of the present investigation are also discussed.

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Ion plated film has good properties, that is, a good adherence onto the substrate, a high strength of the film and a film formation all over the surface without rotation or inclination of the substrate, because ion plating is the new technique by which ions are deposited onto the substrate under the electric field in vacuum. So, it is easily imagined that ion plating technique can be applied to technology at wide region, e.g. application to tribology and strengthening of the materials. In the present research, an ion plating apparatus with the sputtering technique, which can be applied to refractory materials and chemical compounds, was developed, and tensile tests of the advanced filaments covered with B₄C, Cu, and Ti films were performed with an Instoron tensile testing machine. The results of the tensile tests reveal that the proportional limit and tensile strength of the stainless steel covered with B₄C increased up to about 133 % and 126% respectively. Also discussions were made about disruption of advanced filaments with a SEM.

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The present research aims to find the feasibility of machining of the order of atomic size, which is the ultimate unit of machining, by mechanical method, and to obtain the physically perfect mirror surface which is undisturbed crystallographically, and to realize the machining in the accuracy of the atomic size. In machining the surface mechanically, that is, cutting, grinding or lapping, the stress field induced by the cutting edges is large, so that, the machining mechanism is dependent on the deformation or the fracture based on the pre-existing dislocations or cracks, and the unit of machining is large. However, the volume of those defects is negligible to all the volume of material and the great part of material can be assumed to be the ideal crystal structure. Therefore, making the stress field induced by the cutting edge very small, the pre-existing defects may not act and the deformation or the fracture may become elastic and the unit of machining may become minute. Thus, it is supposed that the elastic fracture without plastic deformation in the order of atomic size becomes possible. The machining method based on this fracture is named as “Elastic Emission Machining”. In order to make the size of the stress field smaller than the distance between the pre-existing defects and to verify the feasibility of the elastic fracture in the order of atomic size, the authors intend to finish the work surface by making fine powder particles collide with the work surface. And, the feasibility of EEM is proved, experimentally by the measurement of stock removal and the microscopic and electron diffractive observations of finished surface, and theoretically by comparing the kinetic energy of powder particle with the binding energy of material and comparing the stress induced by the collision of powder particle with the theoretical strength of material.

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Workpieces, which are fed to grinding in a lot, have respective dimensions generated in the previous stage of production and then the stock allowance of each workpiece is distributed in the lot. In this paper, the effects of variations of stock allowance upon dimensional accuracy are theoretically analyzed, based on the accumuration phenomenon in grinding, in case that workpiece dimensions are normally distributed in the lot, by investigating the dimensions of ground parts and their distribution, and the relation between the infeed position of grinding wheel and the percentage of defective products in dimension. It has been made clear that the dimensions of ground products have a close relation to the plunge speed, the sparkout grinding time and the workpiece dimension, that the distribution of product dimensions is not normal and affected by the plunge speed, the sparkout grinding time, the stock allowance and its variance, and that the proper selection of infeed position of grinding wheel makes the percentage of defective products in dimension minimum.

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An expression defining the position of contours is re-examined in moiré contouring system of projection type. The newly obtained expression adds a correcting term involving a phase difference between gratings to the expression used conventionally. Based on the physical meaning of this expression, a new attempt of lateral movement of one grating is introduced to the former measuring apparatus. In this new way, several characteristics are given to the moire pattern method. By moving one grating relatively to the other, the following properties are provided to the system.
(1) Any point on the object may be adjusted to coincide with the contour line.
(2) Distance between two points on the surface and the displacement of the object can be obtained by the measurement of the shifted distance of the grating.
(3) Multiplication of contour lines can be performed by the suitable movement of the grating and the multiexposure.
(4) Judgement may be given whether a part is a hill or a valley by observing the direction of movement of the fringes as the grating is shifted.

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Kinematical analysis on pitch-polising is carried out, assuming that the stock removal and polisher wear amount are proportional to the polishing speed, pressure and time, respectively, while also taking into account distributed pressure on the work due to polisher elastic deformation. Based upon the equation obtained here, calculated stock removal and flatness values for 60 mm diameter glass plate are found to be in good agreement with values obtained experimentally under the same conditions. The relations between flatness and specific polisher wear η_P or elastic deformation rate are calculated numerically. Flatness on a work surface deteriorates with larger specific wear as polishing continues, while the degree of deterioration in flatness is rather small, with respect to elastic deformation.

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Damping capacity is one of the most important parameters in considering the structural design in machine tools. It is not a usual means to use solvant for wiping out oil or grease from bolted joints. So, this paper describes an experimental investigation on dynamic characteristics of bolted joins having a thin layer of lubricant. It is found that the variation rate of bolt's axial force which is in propotion to a relative amplitude of two surfaces shows a smaller value as compared with dry joints. The damping effect of oiled joints dependents on fastening force of bolts and static bending force, however in the case of high contact pressure it is not dependent on them. The effect of lubricant and some other results are described.

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To design a high speed sealed contacts, time durations of contacting noises are analyzed. The reed is replaced by two one-degree-of-freedom vibration systems. In the model, one mass collides and another vibrates with dynamic friction between contacts. Time duration of noises caused by rebounding, T_A, is determined by coefficient of collision and parameter K_A, defined as K_A=ξ/ξ₀ω_A; velocity of collision ξ, angular frequency of vibration system ωA, and equivalent pressing distance ξ₀. T_A increases continuously with an increase of K_A. Noises caused by free vibration, T_B, is determined by equivalent friction coefficient between contacts and the parameter K_A. T_B increases in stair case with an increase of K_A. Experimentally, in an unsymmetrical reed switch, noises are caused by rebounding and by free vibration. In a symmetrical reed switch, noises are caused by only free vibration. Each noise time duration agrees well with calculated values.

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An elastic-plastic-viscoplastic rheological model is proposed to explain the longitudinal plastic waves. This model is composed of five elements and describes an instantaneous and a noninstantaneous plastic response. The calculated values according to the equation derived from this model are compared with the experimental results already reported and those from the elastic-viscoplastic rheological model which are equal to those from the Malvern type constitutive equation. The influences of an instantaneous and a non-instantaneous plastic response on the calculated values, strain - time curve, dynamic stress - strain curve and particle velocity - time curve, are discussed. The main results obtained are as follows :
(1) The calculated values from the present model agree with the experimental results better than those from the elastic-viscoplastic rheological model.
(2) With the increase of a non-instantaneous plastic response, dynamic stress becomes higher and the velocity of small strain becomes higher and that of large strain becomes lower.
(3) With the distance from the impact end, the change of dynamic stress from the proposed model becomes smaller than that from the elastic-viscoplastic rheological model.

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A transmission accuracy of the gear is nearly known by measuring the pitch error in relation to the profile error at the same time. In order to auto-record the above two errors simultaneously, a measuring apparatus similar in mechanism to the gear hobbing machine, which has a gear to be measured and the several detectors of auto-recording electric comparator in place of the gear blank and the hob cutting edge respectively, is used. And by improving on both the arrangement of detectors and the recording system on this apparatus, they have been auto-recorded simultaneously, besides from this record a method for knowing a transmission accuracy has been tried. This method gives a very similar result to the one obtained by the single-flank rolling test, but it has some merits such as that the master gear and the pitch disk are not necessary, the errors at the face and the flank which cannot be shown by the test are known, and the factor of error can be analysed. Moreover this method can be considered as the auto-recording measuring method of profile of all teeth without using the base disk.

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In order to investigate the application of ceramic tools in intermittent cutting, face milling test was conducted on 0.45% carbon steel with several ceramic, carbide and cermet tools. The wear patterns, the wear rates and the tool life were measured and also crater wear was observed precisely with an optical and an electron microscope. Obtained data were analysed to evaluate the wear characteristics of ceramic tools in comparison with those of carbide and cermet tools. Main results obtained are : 1. Ceramic tools are applicable for face milling without tool failure under the selected cutting conditions. 2. Crater wear rate of ceramic tools in face milling is much higher than those of another machining methods. Consequently, 50 μm of maximum crater wear depth is considered to be the suitable tool life criteria from the view point of tool failure. 3. Thermal cracks parallel and normal to the cutting edge are observed in the crater wear region of ceramic tools. Since these cracks in ceramic tools are not so deep as those of carbide and cermet tools, it is considered that they are not essential for the tool failure.

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In up milling, the finished surface is generated only by the initial part of contact between cutting edge and workpiece, in which there exist an elastic and a plastic deformation different from cutting. In this paper, the surface generation mechanism in up milling is experimentally investigated by milling with a single point plain milling cutter. The plastic deformation region exists in the part following the top of tooth mark on the finished surface in milling. The ratio of the plastic sliding length to the finished surface length (the plastic sliding ratio) decreases with increases of the interference angle and the cutting velocity, while it is not affected by the depth of cut. For the plastic sliding ratio larger than one all the finished surface is generated only by the plastic deformation region. The surface finish is closely related to the plastic sliding ratio.

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The relationship between the working gap width and the machining condition was investigated in Electro-chemical Machining using sodium nitrate solution, and the working gap width in machining using sodium nitrate solution was compared with it in machining using sodium chloride solution. The results are as follows.
(1) The relationship between the working gap width and the machining condition using sodium nitrate solution is given by the some relationship that has feed rate increase in machining using sodium chloride solution.
(2) The working gap width can be estimated numerically by using the experimental relationship between the feed rate and the current density.
(3) The working gap width in machining using sodium nitrate solution becomes narrower than that in machining using sodium chloride solution under the some machining condition on supply voltage, feed rate of electrode, and specific conductivity.
(4) The working gap width in machining without feeding the electrode approaches to the steady gap width with machining time.
(5) At the lower current density, dissolution of the work-piece does not proceed in machining with feeding electrode and without feeding electrode.

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The effects of the following factors on the surface roughness in cylindrical plunge grinding are analysed theoretically by a statistical approach :
(1) The wheel depth of cut.
(2) The ratio of the grinding wheel to the workpiece in number of revolutions.
(3) The thread on the grinding wheel surface caused by dressing treatment.
Furthermore, the surface roughness in cylindrical traverse grinding is analysed theoretically by a statistical approach. And experimental results are compared with the theoretical values calculated by use of the measured distributions of the following factors :
(1) The position of grain cutting edges in the radial direction on the grinding wheel surface layer.
(2) The tip angle of grain cutting edges.

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