日本機械学会論文集 C編
Online ISSN : 1884-8354
Print ISSN : 0387-5024
55 巻, 510 号
選択された号の論文の44件中1~44を表示しています
  • 野波 健蔵
    1989 年 55 巻 510 号 p. 235-242
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    A modal control with variable velocity feedback for structural vibration systems is proposed. In particular, two methods of variable velocity feedback are presented. The first method is a design in the actual domain and is based on the following idea : even if the number of velocities measured is less than the number of controlled modes, we only have to supply the ideal control input to the actuators by estimating the unobserved velocities. Therefore, the feedback gains change depending on each mode. The second method is a design in the modal domain and the orthogonality property of the modal coordinates is used in this method. These two methods not only realize an optimal pole assignment for the controlled modes, but also have no effect on the uncontrolled modes. Simulations of the active control of two mathematical models are carried out to verify the efficiency of these methods.
  • 杉山 吉彦, 片山 忠一, 福田 尚男 /, Ramesh C. Kar
    1989 年 55 巻 510 号 p. 243-247
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    The paper deals with the stability of a flexible space structure propelled in space from the assembly station to a maneuvering point by means of an end thrust. The structure is idealized as a uniform viscoelastic free-free beam with a direction-controlled follower force. Both divergence and flutter instabilities occur depending on the manner of control. The aim of this paper is to demonstrate the important effect of internal damping on flutter instability of the beam. It is shown that the flutter value predicted by neglecting the damping in the stability analysis is significantly higher than the value obtained by taking small material damping into account. It is concluded that the stability of a flexible space structure propelled by an end thrust should be investigated by considering viscous internal damping which is inevitably involved in the actual flexible structures, even to a small degree.
  • 張 農, 葉山 眞治
    1989 年 55 巻 510 号 p. 248-255
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    The paper presents a method to identify the global modal parameters of a mechanical structure from the free decay responses, which is based on the State Variable Method expressed in the form of difference state equation. A recursive algorithm is proposed for calculation of the state transition matrix. The modal shapes of a large number of stations for each mode are obtained by making use of the data acquisition system with a few channels, which is resulted from the uniformity of the normalized modal shapes. The generalized mathematical model of the method is related to the other time domain methods. As the illustrative examples, the method is applied to the identifications of global modal parameters of a free-free straight pipe and a "T" shape plate structure. And, the identified results are in good agreement with the analytical ones.
  • 志賀 元弘
    1989 年 55 巻 510 号 p. 256-260
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    To examine how great the difference is between a calculated and a measured value with regard to a resonant amplitude of grouped steam turbine blades, the resonant amplitude of grouped blades was calculated and measured. The turbine blades were excited by an electrical magnet. Therefore, the calculated values of the distribution of the resonant amplitude at the natural frequency nearly agreed with the measured ones. At some measuring position, a difference between the calculated values and the measured ones existed, and the measured values became about twice the calculated ones in the worst case. With regard to the direction of the vibration of the blades and the resonant stress, the calculated values nearly agreed with the measured ones. Therefore, if an exciting force during operation can be decided when designing blades, the vibration amplitude and stress of the grouped blades can be predicted by the calculation.
  • 丸井 悦男, 橋本 正俊, 加藤 仁
    1989 年 55 巻 510 号 p. 261-266
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    This paper deals with the regenerative chatter vibration in a cut-off tool. The chatter vibration and chatter frequency are experimentally observed using cut-off tools of straight shank or bending shank. The vibration energy supply mechanism is investigated by considering the interference effect between tool shank and workpiece surface and the regenerative effect between successive cutting operations. It is clarified that the regenerative chatter vibration of cut-off tools is induced by supplying the vibration energy due to the interference effect. The reduction of the interference effect is effective to reduce the regenerative chatter vibration of cut-off tools.
  • 今村 仁, 鈴木 浩平
    1989 年 55 巻 510 号 p. 267-274
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    Taking a simpified mechanical model of the vibro-impact motions as a typical nonlinear system, dynamic behaviour was studied by using a numerical simulation method. First, 1/n harmonic and subharmonic motions are investigated by means of the Poincare mapping technique, and stability analysis is carried out for these motions. In particulary, a symmetric solution and its bifurcation sets are obtained in an explicit form for the system parameters. Second, in order to investigate a qualitative behaviour of 1/n subharmonic motions in the unstable condition, global analysis is carried out by digital simulation. In addition to regular bifurcation, singular bifurcation phenomena based upon discontinuity of mapping can be recognized. Also, transient chaotic behaviour in which the chaotic attractor disappears can be observed.
  • 小島 宏行, 森平 明宏, 根津 紀久雄, 坂本 賢治
    1989 年 55 巻 510 号 p. 275-280
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    In this report, the nonlinear forced vibration responses of a plate subjected to alternating electromagnetic attractive force are investigated theoretically and experimentally in consideration of the superharmonic and the subharmonic vibrations as well as the harmonic one. In the analysis, first, the electromagnetic attractive force is formulated by applying the least squares method to the experimental results. By the use of this formulation, the matrix equation of motion of the plate is obtained by applying the finite element method. Then, the nonlinear simultaneous equations, which decide the superharmonic and the subharmonic vibrations as well as the harmonic one, are derived by the harmonic balance method and the reduced impedence method. The numerical results carried out by the Newton-Raphson method agree well with the experimental results, and the validity of the present analysis is confirmed.
  • 成田 吉弘, 高橋 栄二
    1989 年 55 巻 510 号 p. 281-285
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    A previously developed optimization technique is extended to determine the optimal support positions of continuous beams. An object function is the fundamental frequency of the beams of variable cross section, and design variables are the positions of several elastic springs. The transfer matrix approach is used to yield frequency equations, and a gradient method is used to find optimal solutions. In numerical examples, linearly tapered and stepped thickness beams are considered.
  • 土屋 和雄, 秋下 貞夫, 井上 正夫, 中島 厚, 狼 嘉彰, 村上 力
    1989 年 55 巻 510 号 p. 286-292
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    This paper describes the damping characteristics of rotor in two radial axis, which are passively stabilized by magnetic bearing. The equations of rotor dynamics are introduced considering the effect of anisotropic stiffness of bearing. From the solution of the equations obtained by applying the method of averaging, the damping characteristics variation of the angular velocity is related to the anisotropy of the stiffness. The limit speed at which the damping factor is equal to zero increases with the difference of bearing stiffness in two orthogonal axes in the plane perpendicular to the axis of the rotation. These relations are examined in an experiment on a one-axis-controlled magnetic bearing.
  • 田中 信雄, 菊島 義弘
    1989 年 55 巻 510 号 p. 293-301
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    This paper deals with an active control of an impact vibration using a preview control. It is the purpose of this paper to realize a servo damper system with the preview control and to verify the capability of suppressing the impact vibration. First, with a view to clarifying the mechanism of a vibration control by preview action, this paper presents a control chart to estimate the preview control effect. Then, based upon the control chart, the superiority of the preview control over a feedforward control is discussed. Next, by placing an emphasis on realizing the servo damper system, a preview control element is modified to be an approximate integral form, with the result that a low gain control element is obtained. Moreover, a hybrid control compensator is proposed, which consists of a digital and an analog component ; that is, one to control a preview time and the other to calculate the control signal. Finally, an experiment is carried out, demonstrating the control effect of the servo damper system with the preview control.
  • 兼森 祐治, 岩壼 卓三
    1989 年 55 巻 510 号 p. 302-309
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    This paper describes the experimental study on dynamic fluid reaction force and moment generated in axially long annular clearance between the rotor and stator of a submerged motor pump or in the balance piston of a turbo pump. For measuring the dynamic fluid force, a test rig was made for having spin and whirl motion of the rotor. In the test, the rotor and the stator were set in concentric conditions and pressure fluctuation, fluid reaction force and flow rate were measured under the basic parameters of rotational speeds and pressure drop across the long seal. In measurement, the moment was obtained from dynamic fluid force and instability threshold (limit) of fluid force was determined. In addition, dynamic fluid force was expressed in terms of the stiffness coefficient, damping coefficient and added mass. It was recognized that moment stiffness coefficient and direct-moement damping coefficient increase with axial flow velocity.
  • 岩壺 卓三, 盛 本成, 松本 俊郎
    1989 年 55 巻 510 号 p. 310-316
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    A new test apparatus, which can simulate various working conditions, is constructed and applied to investigate the static and dynamic characteristics of non-contact seals. In this report the pressure drops and the leakages in four types of annular seals were measured, and the influence of rotor spinning speed on the dynamic characteristics was investigated. As a result, the static characteristics such as the pressure drops and the leakages relate closly to the inlet pressure, but they appear little change for the preswirl velocity and rotor whirling speed. As for the dynamic characteristics, they are largely affected by the rotor spinning speed. The increasing of rotor spinning speed gives an instabilizing effect to the rotor system.
  • 岩壺 卓三, 盛 本成, 松本 俊郎
    1989 年 55 巻 510 号 p. 317-322
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    The dynamic characteristics of annular seals for turbopumps have been experimentally investigated. In the experiment, fluid forces acting on the seal were measured for various parameters such as the preswirl velocity, the pressure difference between inlet and outlet of the seal, the whirling amplitude, and the ratio of whirling speed to spinning speed of the rotor. Influence of these parameters on the dynamic characteristics was investigated from the experimental results. As a result, the dynamic characteristics are largely affected by the preswirl velocity. The positive preswirl velocity plays an instabilizing role, and the negative preswirl velocity plays a stabilizing role in the rotor system. The axial flow through the seal also gives a stabilizing effect to the rotor system.
  • 佐藤 邦夫, 田尻 功郎, 木谷 収
    1989 年 55 巻 510 号 p. 323-329
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    An experimental system has been developed to measure the driving forces, side forces and axial torques of driving and braking tires with a side-slip angle, when they are subjected to a known counterforce form the ground. In this system, four wheel driving equipment with its center of gravity at the center of the four wheels is driven at a given drawbar angle until an equilibrium state to determine the component forces mentioned above. In this study, driving and braking experiments were made to block tires for uneven ground on a concrete road, to experimentally validate the principle of the system. As a result, an equilibrium state was realized, in which the component forces were experimentally determined.
  • 松浦 克昌, 一柳 健
    1989 年 55 巻 510 号 p. 330-336
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    The mechanism which maximizes transmissible sensitivity of force in the hydraulic looper mechanism with high dynamic response in which high hydraulic pressure can be used is studied in this paper. As a result of this study, an experimental machine which has the same dimensions as a practical machine is manufactured for trial. The dynamic characteristics of this machine are analyzed and the factors on responsibility and stability are clarified. Furthermore, by using the experimental machine, an experiment of the strip's tension control is performed and the required performance is obtained.
  • 朴 錫柱, 大熊 政明, 長松 昭男
    1989 年 55 巻 510 号 p. 337-342
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    The Experimental Modal Synthesis Method has many advantages : experimental data can be used easily, modeling errors can be avoided, dynamic characteristics can be acquired directly, less computer memory required, and less CPU time consumed. This paper proposes the modal analysis method of the structure with a general viscous damping property in free-free boundary conditions. It also proposes the Experimental Modal Synthesis Method using the former theory. A test model made by 2 bar components is applied to validate this method. Very good agreement is obtained in lower order natural frequencies. However, some differences appeared in higher orders, which are caused by transferred moments through the joints. The amount of transferred moments may be estimated by the inspection of the linearity of the modes of the connected nodes.
  • 野口 幸雄, 岡村 邦彦, 大貝 晴俊, 川並 高雄, 永沼 洋一
    1989 年 55 巻 510 号 p. 343-348
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    This paper deals with the control system design and simulation of the multivariable control system for bar and wire rod rolling. The control objective in the rolling is to maintain the interstand tension and output height and width of bar and wire rod product as prescribed. In this paper, we take a modern control theory approach to cope with those rolling systems. Based on the optimal regulator theory, a simultaneous control system of tension control and Gauge Meter AGC (automatic gauge control of exit height) is introduced. The control law is implemented by the output vector feedback and the partial state vector feedback. To evaluate the control performance, step responses due to input diameter and input temperature change are computed on a 4-stand tandem model mill. From the computed results, the validity of the present control system is confirmed.
  • 野口 幸雄, 岡村 邦彦, 大貝 晴俊, 川並 高雄, 永沼 洋一
    1989 年 55 巻 510 号 p. 349-353
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    This paper deals with the experimental study of the multivariable control system for bar and wire rod rolling. The control objective in the rolling is to maintain the interstand tension and output height and width of bar and wire rod product as prescribed. Based on the optimal regulator theory, a simultaneous control system of tension control and Gauge Meter AGG (automatic gauge control of exit height) is introduced. The control law is implemented by the output vector feedback and the partial state vector feedback. To evaluate the control performance, step responses due to input diameter and input temperature change are measured on a 4-stand tandem model mill. From the experimental results, the validity of the present control system is confirmed.
  • 臼井 清 一, 谷 和男, 堀内 英一, 白井 信正
    1989 年 55 巻 510 号 p. 354-358
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    Among robotic locomotion mechanisms, a wheel method is best suited for high speed locomotion and high energy efficiency, but it is restricted to even road surfaces. In this paper, an active suspension is applied to a wheeled robotic vehicle to suppress the vibration of the vehicle caused by the road's roughness. An experimental device composed of a vehicle simulator and a road simulator is manufactured. The vehicle simulator is a one-wheel model using a direct drive motor for a suspension actuator. The control method is based on the discrete optimal control theory and uses the data gained from the internal sensors. Experimental results show that the estimation of the state values by the internal sensor signals is effective and the high performance of the vehicle body stability is achieved by suspension control during the run on the uneven road surface.
  • 福田 敏男, 細貝 英実, 大塚 雅司
    1989 年 55 巻 510 号 p. 359-364
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    The path planning is very important for the pipeline maintenance robot because there are many obstacles on pipeline such as flanges and T-joints and others, and because pipelines are constructed as a connected network in a very complicated way. Furthermor, the maintenance robot Mark III previously reported has the ability to transit from one pipe to another the path planner should consider. The expert system especially aimed for path planning, named PPES (Path Planning Expert System), is described in this paper. A human-operator has only to give some tasks to this system. This system automatically replies with the optimal path, which is based on the calculation of the task levels and list of some control commands. Task level is a criterion to determine one optimal path. It consists of the difference of potential energies, the static joint torques, velocity of the robot, step numbers of the grippers' or body's movement, which the robot requires. This system also has graphic illustrations, so that the operator can easily check and understand the plant map and the result of the path planning.
  • 福田 敏男, 新井 史人, 細貝 英実, 矢島 信之
    1989 年 55 巻 510 号 p. 365-372
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    This paper describes the control strategy of the bending-torsion coupled system. The effect of the residual modes and the coupling modes in the closed loop controlled system is made clear and the control strategy for the spillover problem in the coupled system is presented. Next, considering the case when one uses the optimal gain, which is determined from the uncoupled model in the coupled system, we study the stability condition of that controlled system. In the stable region, we define the coupling influence degree (CID) for the evaluation of the control performance. Then, using CID, we report the desirable control strategy for the designer who uses the uncoupled model in the coupled system.
  • 小柳 志郎, 岡本 勲, 藤森 聡二, 寺田 勝之, 桧垣 博, 平石 元実
    1989 年 55 巻 510 号 p. 373-381
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    Negotiating curves at high speeds is desired. For the purpose of improving the ride quality on a curved track, an active tilting system fro railway cars is studied theoretically. This system is composed of a curve detector, curve data memories, microcomputers for making control signals, feedback circuits of swing angles, and air servo mechanisms. With the dynamic model of this system, after the kinematic equations are led in several control modes, the optimization in simulation analysis and the comparison between measured and calculated waves are described.
  • 小西 康夫, 青山 藤詞郎, 稲崎 一郎
    1989 年 55 巻 510 号 p. 382-388
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    This paper describes the learning control method of a parallellink direct-drive robot manipulator. The acceleration error is used to correct the motion of the direct-drive motors. A theoretical method, which estimates the convergent limit of the learning control process based on the limit of a geometric series, is proposed. The validity of this proposed theory is proven through computer simulation ; it is then applied to the practical system of a parallel-link direct-drive robot manipulator. The convergent limit of a learning control system can be quantitatively estimated by the divergent coefficient which is defined in this study.
  • 田中 正夫, 瀬口 靖幸, 山口 智久
    1989 年 55 巻 510 号 p. 389-395
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    The truss-type arm with high redundancy works by changing the length of the each member actively and independently due to its statically determinate feature. Redundant arms are currently being studied by a number of investigators because of their potential to realize the flexible and adaptive arm motion. In this paper, we discuss the motion planning problem as to how to properly use the redundant degrees of freedom under the required working environment and the solution procedure of global motion planning based on the dynamic programming algorithm is proposed. This method, using an initial estimation of the incremental sequence of arm motion is suitable for the high redundant arm. The results of numerical simulations of local and global motion planning show the effectivencess of this method as well as the assessment of the various criteria.
  • 岩本 勝美, 堀 幸夫
    1989 年 55 巻 510 号 p. 396-400
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    Chiu studied the static characteristics of swing pad journal bearings for horizontal rotor. however, he used the experimentally obtained spring-constant values of the rubber support in his analysis. Therefore, the result can be applied only to the particular bearing he studied. For a more general treatment, in this paper, the spring constant was calculated by means of the finite element method and the influences of five geometrical parameters on the bearing characteristics were calculated.
  • 矢鍋 重夫, 山下 茂, 坂崎 輝
    1989 年 55 巻 510 号 p. 401-406
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    Concerning a measurement of oil film coefficients of journal bearings, a new method is proposed in which a test bearing is fixed to a base rigidly as it is used ordinarily. Spring coefficients of oil film were obtained by measuring deviations of the journal center due to a small load exerted to a rotor. Damping coefficients were obtained by measuring bearing dynamic loads and journal center vibrations due to rotor unbalance. Experimental values were compared with predicted ones, and it was found that both were in good agreement, except cxx and cyy, as shown in other reports. Further, the complex eigenvalue analyses of the test equipment were carried out using the experimental values of oil film coefficients, and the results were compared with that obtained by blow tests. The results show that the proposed method is available for practical use.
  • 賀勢 晋司, 西野 直也, 松岡 浩仁, 須古星 武志
    1989 年 55 巻 510 号 p. 407-410
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    With the aim of improving the calibrated-wrench method, an axial tension control method based on an in-process prediction of a final fastening torque is presented. The prediction is performed by the detection of the differences of the fastening torque and corresponding rotational angle or time between a set interval and by a comparative calculation between the above values of the differences and set values. Although the value of the compliance of the bolt-nut joint is requisite, a reliable control with respect to each fastening process is expected without the difficulty of knowing the torque coefficient. Experiments using an experimental apparatus aided by a personal computer show fairly good results under various conditions. Lastly, some problems in the accuracy of the control are discussed.
  • 木村 弘之, 野中 重夫
    1989 年 55 巻 510 号 p. 411-416
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    In order to analyze the vibration of a structure connected with bolts, it is necessary to estimate the rigidity of bolted connections. Some studies have been reported on annular flange connections. In these studies, the bolt axial force and the sealing performance are examined in detail, but the rigidity of annular flange connections is not sufficiently discussed. This paper deals with a calculation method for estimating the rigidity of bolted annular flange connections subjected to external loads in the axial direction. In the analysis, a model for estimating the axial rigidity of annular flange connections is proposed taking into account the dispersiveness of bolt disposition and the rigidity of flange-shell junction. That is, the annular flange is replaced with a plate and the hub with a cylindrical shell. For verification, experiments are carried out. Calculated results are in fairly good agreement with experimental ones.
  • 新田 勇, 木越 健二, 加藤 康司
    1989 年 55 巻 510 号 p. 417-423
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    A new method of shrink fit between a ceramic shaft and an outer metal ring with the use of an insert ring has been developed in this paper. An insert ring, which has a higher coefficient of thermal expansion than that of the outer ring, was inserted between the ceramic shaft and the outer ring where the insert ring was cut in the radial direction into some pieces. The fitting strengths of these shrink fitted assemblies were measured from room temperature up to 600°C. The effect of number of cutting in the insert ring on the fitting strength at elevated temperature was researched. It was revealed that the cutting of the insert ring into over three pieces was requisite to ensure the fitting strength at elevated temperatures. We were able to design the fitting strength-temperature relationship by changing thickness of the insert ring in radial direction. For example, the fitting strength would increase when the insert ring was thick enough as the temperature was raised. And the fitting strength would decrease when the insert ring was thin enough as the temperature was raised. Expressions which estimate the fitting strengths were also developed in this paper.
  • 藤城 郁哉, 中村 裕一, 桝井 克修
    1989 年 55 巻 510 号 p. 424-430
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    A new technique to obtain viscoelastic property of lubricants under high pressure over 2 GPa is proposed. Tested lubricants are BCCM and DMP, which have high viscosity-pressure coefficients. From the difference of the ruby fluorescence wavelength between (0001) and 112^-0) ruby plate in diamond-anvil apparatus, shear stress relaxation can be observed. By applying Maxwell model for the relaxation analysis, the extremely high viscosity (over 1015Pa·s) is obtained and is almost fitted with the extrapolated value of the existed one. Bulk viscosity and elastic modulus are also obtained and are consistent with the existing values.
  • 和栗 雄太郎, 浜武 俊朗, 副島 光洋
    1989 年 55 巻 510 号 p. 431-436
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    The crosshead-pin bearing equipped with axial oilgrooves in a two-stroke cycle diesel engine cannot produce such a thick oilfilm as to hold the bearing to be always free from troubles since the bearing is subjected to high load in a single direction besides a low speed. This paper refers to a theoretical analysis on the lubrication of a crosshead-pin bearing with an elliptical bearing and a circular journal. This bearing can remarkably increase the oilfilm thickness and is superior to the conventional bearing in load-carrying capacity and oilfilm exchanging ability as the wedge film action greatly increases due to the presence of two converging-diverging film shapes in load-carrying film.
  • 藤城 郁哉, 中村 裕一, 曹 貴和, 藤居 良隆
    1989 年 55 巻 510 号 p. 437-442
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    Viscosity of several synthetic lubricants is measured in a diamond-anvil high-pressure cell by falling sphere method at elevated temperature. Viscosity-pressure coefficients of bicyclohexylcyclo-hexylmethane, dimethylsilicone and their mixture are obtained, which are important in elastohy-drodynamic lubrication and traction coefficient. In order to discuss the property of the mixture, Wright method is applied and shows agreement with this data. Viscosity-temperature characteristics under high pressure are also discussed using Walther's equation, and this equation proved to be effective even under high pressure. Factors relating viscosity-temperature property of the mixture are close to those of dimethylsilicone.
  • 矢部 寛, 山本 穣
    1989 年 55 巻 510 号 p. 443-450
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    The bearing characteristics, such as bearing stiffness and the damping coefficient, of an externally pressurized gas-lubricated thrust collar bearing with multiple supply holes are analyzed theoretically. A point source solution is applied to evaluate strictly the bearing characteristics. The dispersion effects due to the discrete location of the supply holes are discussed by comparing the point source solutions with the solutions obtained under the line source assumption. The effects of the deviations of the forms of the bearing, such as perpendicularity of the rotor end surface, size deviation of the supply holes and flatness of the bearing plate, to the bearing characteristics are also discussed.
  • 小尾 誠, 熊谷 俊司, 安原 和彦, 岩里 茂
    1989 年 55 巻 510 号 p. 451-454
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    The grinding wheel elasticity should be considered as one of factors which cause the grinding un-removal. Thus, it has been investigated by many researchers. But the many of these studies have considered the grinding wheels static. In this paper, the grinding wheel elasticity and its rigidity are considered as the grinding condition experimentally and theoretically. The main results are : 1) The rigidity of a grinding wheel in the grinding state is larger than in the static state and as the value of grinding, force, the difference increases further. 2) The rigidity of a grinding wheel in the grinding state is considered as a dynamic model of a grain or some grains.
  • 土井 雅博, 益子 正巳, 竹内 成樹
    1989 年 55 巻 510 号 p. 455-460
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    In this paper, the chucking behaviors of power chuck were investigated experimentally. The fluctuation of chucking force during actual cutting had not yet been measured up to this time. Especially, behaviors of the chucking force under the existing of chatter vibration were ascertained in detail. The results obtained from this study are as follow : (1) Fluctuation of the chucking force is generated, similar to the scroll chuck, periodically due to the combined effects of directional orientation of the chucking stiffness and the cutting force. (2) Under the condition of high speed spindle, the decrease of the chucking force on power chuck is bigger than that on scroll chuck by decreasing of friction force. (3) In the case of power chuck, the decrease of the chucking force after cutting with the mechanism of compensation is smaller than the case of scroll chuck.
  • 村田 眞, 横内 康人, 鈴木 秀雄
    1989 年 55 巻 510 号 p. 461-465
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    In the shearing of thin tubular workpieces by an electromagnetic forming method, the effects of the shearing are investigated experimentally. The charged voltage of the condenser bank, the width of the shearing parts, the types of materials, and outer diameter thickness of the workpieces are used as experimental parameters. The shearing mechanism is such that the shearing parts are stretched and cut off with their bulging. The cut edges of the shearing have a small shearing droop and a large fracture surface. The rates of the shearing are very fast, and the forming method is excellent. The minimum charged voltages for the shearing increase with increasing the thickness of the workpieces and decreasing the diameter and the width of the shearing parts.
  • 高井 昭, 渡辺 寛, 萩原 秀彦, 松川 彰広
    1989 年 55 巻 510 号 p. 466-469
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    A wince dyeing machine has many practical merits, so it is widely used in dyeing works. However, it also has demerits : necessity of some manual procedure and occurence of ocassional dyeing specks. The purpose of this research is to improve these points. For reducing the manual procedure, a system which feeds liquid dye into liquid auxiliary was planned. For the prevention of dye specks, a new and simple circulation system was approved. The results of the experiment will show that the proposed system is effective in practical production.
  • 岩田 一明, 杉村 延広, 彭 羅生
    1989 年 55 巻 510 号 p. 470-475
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    A mathematical analysis of product surfaces is carried out, aimed at developing a logical design methodology of machine structures which can generate a set of product surfaces. The relationship between the product surfaces and the shape generation process is analyzed, and formulae representing this relationship are established. Algorithmic procedures are proposed to determine feasible kinematic functions for the individual product surface, and to design a suitable combination of the kinematic functions which are applicable to the machining of all the product surfaces.
  • 藤本 英雄, 山下 俊之
    1989 年 55 巻 510 号 p. 476-483
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    A new FMS simulator was developed. The simulator has a function to make a workers model, and has various kinds of output functions applicable to production scheduling. In the first stage example, the simulator was applied to a real FMS. For the estimate, the total production time was considered, and the scheduling problem, that is, the selection of the dispatching rule for the introduction of the parts by the workers was solved using the simulator. In this approach, for the complicated FMSs under several conditions, simulation experiments can be performed, and results obtained form the FMS can be discussed easily. In this application example for a real FMS, several results were obtained.
  • 藤本 英雄, 坂根 英樹
    1989 年 55 巻 510 号 p. 484-491
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    In order to estimate FMSs, a simulator was developed, and various types of scheduling were investigated. This simulator uses the variable increment method as the time control, and introduces a modeling technique using events. To enable a real simulation, this simulator not only has the function of modeling the workers activities but also of modeling the jigs and machine tools. Scheduling for selecting the machine to handle the parts was formulated. Techniques utilized several kinds of progress information, that is, the percent of each machine utilization in dynamics of integrated production time for parts. For the scheduling techniques, the percent of machine utilization and residence time were chosen as criteria, and simulation experiments were performed for the application example : the results are discussed in this paper. It was found that due to the functions of the simulator, analysis of FMSs under various conditions could easily be performed.
  • 京極 秀樹, 打田 澄雄, 片岡 豊
    1989 年 55 巻 510 号 p. 492-497
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    A computer aided design (CAD) system was developed in order to establish the systematic strength design method of adhesively bonded joints. This system was composed of two parts as follows : (1) the stress analysis and the strength prediction were performed using the finite element method and the strength criterion, and (2) the optimum adhesive length and other dimensions of the joint were determined by the predicted joint strength. This method was applied to the design of single lap joints, scarf joints (including butt joints) and shaft joints. It was verified that this system could be successfully applied to the stress analysis of joints using the auto-meshing processor and the finite element method processor, and to the prediction of joint strength using the strength criterion. The relation betwees joint strength and dimension were graphically obtained. The optimum adhesive length and other dimensions of joints could be chosen by the graphic representation of joint strength under static loadings.
  • 本間 恭二, 西村 司
    1989 年 55 巻 510 号 p. 498-502
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    A 15 MHz surface Rayleigh wave system with computer controlled data acquisition and analysis was used to study the detection and characterization of surface flaws in ceramics. Rayleigh waves were generated by placing a focused transducer at critical angles with respect to the test specimens included with artificial flaws and indentation flaws. The scattering of the waves into water by the surface flaws was detected, analysed in the time domain and correlated with the size and the shape of the flaws. The surface Rayleigh wave technique by the device could detect flaws as small as 40 μm deep on soda-lime glass and 50 μm on silicone nitride.
  • 田中 裕久, 増田 健二
    1989 年 55 巻 510 号 p. 503-507
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    Automotive automatic power transmissions have pressure control valves which control the pressure of wet-clutches or band-brakes. Recent transmissions have replaced hydromechanical valves with electrohydraulic valves for the improvement of shift quality at gear changes. A conventional proportional pressure control valve is controlled by a solenoid with a triangular leakage path of magnetic pressure control valve is controlled by solenoid with a triangular leakage path of magnetic flux which causes lower is controlled by a solenoid with a triangular leakage path of magnetic flux which causes lower reproducibility and productivity. It is difficult for a single stage valve to control high flow rates. Here, we have designed a new type of proportional solenoid with a rectangular leakage path in a magnetic circuit with the aid of FEM analysis, and control a secondary valve by a primary valve with a spool of 2mm in diameter. The dynamics of the valve and the pressure control system are simulated by bond graphs which manipulate nonlinear elements symbolically.
  • 池内 健, 岡 正典, 森 美郎
    1989 年 55 巻 510 号 p. 508-515
    発行日: 1989/02/25
    公開日: 2008/02/21
    ジャーナル フリー
    A flow in both the articular cartilage and the gap between the cartilages is considered in a numerical analysis of deformation and lubrication in a hip joint. The results show that a circumferential zone with contact points appears just after step loading while high-pressure fluid is trapped at the center. Then, creep deformation follows in the contact zone due to an outward flow from the cartilage to the gap, and it contributes to improvements in the conformity and the lubrication. It is found that each of the non-Newtonian viscosity of the synovial fluid, the flow in the cartilage and the deformation of the cartilage and subchondral bone plays an important role in the squeeze film effect in a hip joint.
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