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Volume 43, Issue 513
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[in Japanese]1977 Volume 43 Issue 513 Pages 998-1004
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSDownload PDF (1802K) -
Curve Design and Initial Surface Generation Methods (1) (2)Fujio YAMAGUCHI1977 Volume 43 Issue 513 Pages 1005-1011
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSIn the first half of the paper several techniques are presented to modify and control a Bspline curve in connection with the data structure presented herein. The curve data structure is embedded with matrices for finite difference computation and allows to automatically determine the curve segments to be re-computed when a vertex of the curve is moved. These techniques help design the curve in a rubber band fashion on a graphic display. In the last half two methods are presented for generating initial surface models for design which maintain the basic features of the design shapes delineated by a designer with curves. One is a surface of revolution about a vertical axis and the other is a quasi-surface of revolution about polygonal axes. These surfaces are represented in the data structure as special cases of a more general surface and can be modified to other complicated shapes.View full abstractDownload PDF (1153K) -
Worked Layers of Ferrites (2nd Report)Junji WATANABE, Yoshiyuki UENO, Seiji SHINOYAMA1977 Volume 43 Issue 513 Pages 1012-1017
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThe worked layers of polished ferrites were estimated by electron-diffraction method and the principal mechanism of magnetic characteristic changes was clarified. Effective non-magnetic layer of abraded ferrites can be estimated by measuring reluctance of a toroidal core with worked layers perpendicular to magnetic path : the depth of the layer was obtained by the method as 0.2μm for polished Ni-Zn ferrites, when its plastic deformation layer was 0.6μm from the measurement by the electron-diffraction method. On the other hand, the change of permeability in the ferrite thin plate with abraded surface can be explained by magnetostrictive effect caused by residual stress of worked layer. In this work, the relation between permeability and stress is deduced, and is proved by measuring the residual stresses, magnetostriction constants and permeabilities of Mn-Zn ferrite single crystal.View full abstractDownload PDF (1135K) -
Studies on Wear and Redress Life of Grinding Wheel (4th Report)Kuniaki UMINO, Noboru SHINOZAKI1977 Volume 43 Issue 513 Pages 1018-1024
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSIn the case that a suitable grinding wheel is used under the optimum grinding condition, the purpose of grinding operation is attained. Even if the optimum grinding condition is established, the reasonable grinding operation cannot be done, when the selection of wheel grade is mistaken. So in grinding operations, the problem of wheel selection becomes most important. In this paper, the standard of wheel selection is considered on the theoretical basis. The results obtained are as follows :
(1) The suitable wheel grade for grinding operation is given by
E=1/-k5elog {1-mrθrJB√d0√kρc√υl/0.95k4 qR wV}
or
Zg=mrθrJB√d0√kρc√υl/0.95k3 qR wV
Where, E : the modulus of longitudinal elasticity, Zg : the symbol mark of wheel grade, k4 : a constant, k5 : a constant, mr : the rate of normal force to tangential force, q : a constant, Rw : the flowing rate into the work of heat, θc : the critical grinding temperature corresponding to the occurence of burn mark, J : the heat equivalent of work, k : the thermal conductivity of a workpiece, ρ : the density of a workpiece, c : the specific heat of a workpiece, do : average grain diameter, l : the contact arc length between a wheel and a workpiece, V : wheel speed, υ : work speed, B : the width of grinding.
(2) The standard of wheel selection in case that the type of grinding and grinding conditions change can be obtained.View full abstractDownload PDF (1337K) -
Reinforcing Effect to Active Grits and Restraining Effect from LoadingAkira YAMAMOTO, Takashi UEDA1977 Volume 43 Issue 513 Pages 1025-1030
Published: September 05, 1977
Released on J-STAGE: January 20, 2010
JOURNAL FREE ACCESSOn the contributing mechanism of the sulfur filled in a stick to an elevation of stick's finishing performance, two marked effects indicated in the title were further investigated. This was chiefly done by comparing sulfur with some filling materials having a noticeable feature. The main results are as follows. (1) The bending and the tensile strength of porous materials like a stick can be fairly reinforced by sufficiently stuffing the pore with the filling, even if filling's strength were much weak. (2) The scratch hardness on stick surface at elevated temperature supports the conclusion that, at a stick working surface temperature above melting point of its filling material, the reinforcement to active grits by the filling is quite gone and consequently the finishing performance gets worse. (3) The colorimetric analysis of metal loading at the stick working surface shows that the filling greatly restrains loading. Furthermore, in the untreated stick, increase of metal loading also reinforces active grits and lifts up the critical stick pressure. While in this stick an adequate loading contributes to elevation in surface roughness, in the treated sticks with effective filling materials the amount of loading seems to have no relation to the surface quality.View full abstractDownload PDF (1116K) -
Masataka NAKAGOME, Ken TERAO, Masao MIZUNO1977 Volume 43 Issue 513 Pages 1031-1036
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThe theoretical expression for the calculation of the optimum clamping force of the boltconnection with the clamping force extended plastic region under constant external mean stress was inducted with the following three assumptions :
(1) The bolt carries only the axial stress.
(2) The material of the bolt is elastic-lineally plastic solid.
(3) There is no plastic deformation in the fastened body. Also, the effect of pre-stressing by clamping was investigated theoretically and experimentally.
The results are as follows :
(1) With the optimum clamping force, the endurance limit increased about 170% against the conventional value, at mean stress σm= 31.5 kg/mm2.
(2) The theoretical value in the optimum clamping force nearly fitted to the experimental value.
(3) The endurance limit was more improved when the optimum clamping force was given after the pre-stressing.View full abstractDownload PDF (1113K) -
Chip FormationSusumu KASEI, Masahiro MASUDA, Kozo YOSHIKAWA1977 Volume 43 Issue 513 Pages 1037-1043
Published: September 05, 1977
Released on J-STAGE: January 20, 2010
JOURNAL FREE ACCESSIn this paper, chip-flow angle, cutting ratio and so forth are experimentally investigated in turning with a positively driven rotary cutting tool, which is rotated with a midget oil motor. The chip formations are discussed from two standpoints of an effective rake angle and a tool-chip contact area comparing with those of the orthogonal cutting and the oblique cutting. The results obtained are as follows.
(1) The cutting process in cutting with the rotary cutting tool is explained by the variations of an effective rake angle and the tool-chip contact area.
(2) As the tool rotating velocity increases, an effective rake angle is seen to increase. Therefore, it is expected that the rotary cutting tool may improve the cutting performance.
(3) The cutting ratio in this cutting is similar to that in the orthogonal cutting except for an influence that the increase of chip-flow angle causes the increase of the chip thickness.
(4) The larger cutting ratio in the orthogonal cutting brings about the smaller chip-flow angle in the three dimensional cutting.View full abstractDownload PDF (1282K) -
A Method Using the Change of Thread Generated on the Wheel Face by DressingSeiki MATSUI, Ryozo MAENO, Jun'ichi TAMAKI, Takashi HASEGAWA1977 Volume 43 Issue 513 Pages 1044-1049
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThis paper describes a new criterion to determine the wheel redress life in fine cylindrical plunge grinding. In most cases of dressing using a single point diamond dresser a thread is generated on the wheel face, and the thread, changing its form with the lapse of grinding time, finally disappears. In fine cylindrical plunge grinding the wheel face profile is printed on to the workpiece surface and the same thread is generated on it. The wheel redress life based on the new criterion is determined as follows : changes in the ground surface profile with the lapse of grinding time are pursued by means of spectrum analysis, and when the thread caused by dressing disappears, it is considered that the wheel has just reached its wheel redress life. A few experiments were carried out to compare the new criterion with the criteria heretofore in use, and the new criterion gave almost the same wheel redress lives as those based on the normal grinding force or the radial wheel wear.View full abstractDownload PDF (1175K) -
The Ballizing of SteelTokio MORIMOTO, Kentaro TAMAMURA1977 Volume 43 Issue 513 Pages 1050-1055
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSIn the burnishing process, the effects of some kinds of fluids are investigated on the working forces and the surface quality as well as the anti-adhesive property, to clarify the working mechanism of fluids. The experiment is performed by forcing the hard ball through an undersized hole, hereafter this procedure is called ballizing in this paper. In order to evaluate the lubricating effects of fluids, the penetrating forces are measured by means of strain gauges. The effects on the work are studied from the micro vickers hardness in the cross section, surface roughness and plastic flow of surface layer, etc. The results are as follows : 1) In the ballizing, the viscosity of fluids, not the EP lubricants, has the most influence on the working forces. The increasing of the viscosity causes the increasing of the forces. 2) Surface roughness is much improved in application of the fluid having the higher viscosity rather than the lower. 3) In the ballizing, the workpieces are most work hardened at a few micro meters distant from the inner surface. And its work hardening is greater in use of the fluid having the high viscosity rather than the low viscosity.View full abstractDownload PDF (1588K) -
Keiichi NAGAKURA1977 Volume 43 Issue 513 Pages 1056-1062
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThis paper describes minimum-time positioning control using a DC servomotor. The control consists of two modes. One is Bang-Bang control, the other is linear feedback control. The angular position of shaft is controlled by Bang-Bang input at first. When the angular position arrives at the neiborhood of objective point, the feedback input acts to regulate the state instead of Bang-Bang input. The main conclusions are as follows.
(1) The control system which consists of Bang-Bang control and feedback control is available for positioning on printer.
(2) As the new feedback element to compensate the unknown disturbances, the integral of angular displacement is inserted in feedback control.
(3) The rejection filter is inserted in velocity feedback loop to stabilize the control system.View full abstractDownload PDF (1121K) -
Eiji USUI, Takahiro SHIRAKASHI, Toshiyuki OBIKAWA1977 Volume 43 Issue 513 Pages 1063-1068
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSIt has been pointed out by several workers that carbontetrachloride as cutting fluid and manganese sulfide as free machining additive make the shear deformation appear more brittle in metal cutting. It is not clear, however, whether the embrittlement really gives rise to an increase of the shear angle and a reduction of the coefficient of tool face friction as usual cutting fluids do. In order to ascertain this problem, a computer simulation of cutting fluid action in a slow speed orthogonal cutting is conducted by applying the finite element method. From the viewpoint of the continuum mechanics, the embrittlement may be approximated to a reduction of strain hardening or material strength in the shear zone. When the such reduction is introduced to only the workpiece surface-layer or to the whole, shear zone, it is found that the shear angle increases, the chip becomes thinner, and the cutting force decreases, while the tool-chip contact length, the shape of the stress distribution and the coefficient of friction on the tool face are remained almost unchanged. On the contrary to this, the contact length is shortened remarkably and the cutting force is concentrated near the cutting edge, when the tool face friction is reduced directly.View full abstractDownload PDF (1309K) -
Theorization of Locking Performance CurveAkira YAMAMOTO, Shinji KASEI, Teruyoshi KUBO1977 Volume 43 Issue 513 Pages 1069-1074
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSPreviously, the authors proposed δ-S curves to evaluate the locking performances of threaded fasteners under transverse vibration, where 3 means the loss of the fastening force per cycle at the specified fastening force and S the full amplitude of vibrating displacement. This paper aims at theorization of the δ-S curves in the threaded fasteners without locking devices. The theory of self-loosening mechanism analysed in the previous paper is developed and applied to obtain the theoretical curve of the relation between δ and S. Experiments are performed in two fastening force levels (1 000 kgf and 2 000 kgf) for two diameter-pitch relations (M 10 and M 10 × 1.25), for two different mean diameters in bearing surface of nuts (13 mm and 15.8 mm) and for three fitting clearances (differences between virtual pitch diameters of bolt and nut threads : 35, 150 and 255 μm). The experimental results are fairly in good agreement with the theoretical curves.View full abstractDownload PDF (998K) -
Reducing a Residual Vibration by Use of a Dynamic Vibration AbsorberYoshitsugu KAMIYA, Masaharu TAKANO1977 Volume 43 Issue 513 Pages 1075-1080
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThis paper deals with a vibration problem of intermittent motion mechanisms which have been generally applied to automatic machines. When an intermittent motion mechanism is driven at a high speed, the vibration which occurs in cam-rise mode also remains in camdwell mode because of the lack of the stiffness of the system, the backlash existing in input axis, and other reasons. This residual vibration in cam-dwell mode causes positioning errors at dwelling time, and therefore it prevents the intermittent motion mechanism from working at a high speed. Here, a dynamic vibration absorber is taken up to reduce this residual vibration. This absorber is very effective when a damping device cannot be attached between the vibration system and a fixed point. It is one of the merits to use the dynamic absorber that it is not necessary to take into account the backlash or other causes for the design of dynamic intermittent motion system. The optimal parameters for reducing a transient vibration are obtained, and these are different from those to minimize the steady state vibration with an affection of external force.View full abstractDownload PDF (996K) -
Relation between the Electrolyte Temperature and the Working Gap WidthKoichi NOTO1977 Volume 43 Issue 513 Pages 1081-1086
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThis paper describes the relationship between the electrolyte temperature and the working gap width in Electrochemical Machining using sodium nitrate solution. The working gap width is investigated from the relation between the electrolyte temperature and the current efficiency which was obtained experimentally. The results are as follows.
(1) The relation between the electrolyte temperature and the working gap width can be obtained from the relation between the electrolyte temperature and the current efficiency.
(2) At the low feed rate, the working gap width in machining of high electrolyte temperature becomes narrower than that in machining of low electrolyte temperature. The working gap width is hold constant regardless of the electrolyte temperature in machining of some feed rate.
(3) The working gap width in machining without feeding the electrode at high electrolyte temperature becomes narrower than that at low electrolyte temperature with machining time.
(4) Even if using a non-insulated electrode, a straight hole can be obtained.View full abstractDownload PDF (1012K) -
Effect of Workpiece Supporting Stiffness Variation on Geometrical Accuracy in Plunge GrindingToshikatsu NAKAJIMA, Heisaburo NAKAGAWA, Noboru TSUYUMINE1977 Volume 43 Issue 513 Pages 1087-1092
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThe plunge grinding process, in which the workpiece supporting stiffness varies in a workpiece rotation, is analyzed to make it clear how the stiffness variation affects geometrical accuracy. The grinding force varies together with the stiffness variation through the sparkin and the sparkout state, and the force variation disappears in the steady state and after the effective sparkout state. The positions on the circumference of workpiece, where the grinding force becomes maximum or minimum, can be determined by the grinding force ratio. Due to the stiffness variation the runout is generated on the workpiece. The amplitude of runout increases with grinding time in the sparkin state, and becomes constant and maximum in the steady state, and then decreases with grinding time down to the final value, that has a close relation to the workpiece weight, in the sparkout state. The positions on the circumference of workpiece, where the workpiece size becomes maximum or minimum, are affected by the grinding force ratio and the workpiece weight.View full abstractDownload PDF (1089K) -
A Study of Electron Beam DrillingToshiyuki MIYAZAKI, Shunro YOSHIOKA, Tatsuo KIMURA1977 Volume 43 Issue 513 Pages 1093-1098
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSIn electron beam drilling of metals, drilling characteristics depend on physical constants of metals to be drilled and on drilling conditions of pulsed electron beam to be used, i. e., beam power, beam diameter, pulse duration, number of pulses, etc. In the present paper, the drilling characteristics are experimentally studied on various kinds of metals by varying pulse duration and number of pulses. The effects of these conditions on drilled diameter and on drilled depth were obtained. The drilled diameter varied with the pulse duration slightly, but did not vary with the number of pulses used. The drilled depth varied both with the pulse duration and with the number of pulses. The effect of number of pulses on the drilled depth could be explained based on a proposed model of drilling mechanism. Moreover, it has been discovered that various relations between the pulse duration and the drilled depth for individual metals can be summarized to a single general relation between a normalized pulse duration and a normalized depth.View full abstractDownload PDF (1016K) -
Oil-film Pressure around the Drill TipYoshio HASEGAWA, Osamu HORIUCHI, Yoshinobu MURAKAMI1977 Volume 43 Issue 513 Pages 1099-1105
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThe drill tip in a hole is considered to be equivalent to the journal of an externally pressurized partial bearing, where the cutting force corresponds to its bearing load. The behavior of drill tip is influenced by characteristics of the modified journal bearing. In this report, the oil-film pressure around the drill tip is investigated both experithentally and theoretically. Some results obtained are as follows.
(1) The oil-film pressure, of which the great part is hydrostatic pressure due to the supply pressure of cutting fluid, decreases gradually along the longitudinal axis of drill tip. Its distribution varies subtly with the change of the drilling feed or the attitude of drill tip.
(2) The oil-film force component perpendicular to the rake face becomes large with increase of the supply pressure. Under a constant supply pressure, however, it does not vary so much in spite of the change of the drilling feed or the attitude of drill tip. The other component pararell to the rake face, which directs usually towards the margin, shows a large increase when the drilling feed decreases and the drill tip floats antagonizing the cutting force.View full abstractDownload PDF (1109K) -
[in Japanese], [in Japanese], [in Japanese]1977 Volume 43 Issue 513 Pages 1106-1112
Published: September 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSDownload PDF (1335K)
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