著者
武藤 大輔 高野 靖
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.74, no.746, pp.2495-2503, 2008-10-25 (Released:2011-03-04)
参考文献数
5
被引用文献数
3 3

The dependence of transmission loss (TL) of a double-wall structure on the characteristics of the gases between the walls was investigated. The relationship between acoustic impedance, acoustic velocity, and TL was calculated by using the transfer matrix method. The results indicated that characteristics of the internal gases have two effects on TL. One is a change in the double-wall effect, and the other is a change in the reflection coefficient. Gases that have slower acoustic velocities or lower acoustic impedance than air increase the double-wall effect. Gases that have faster acoustic velocities increase the reflection coefficient. The calculated results for TL with air, helium, and carbon dioxide agreed well with experimental measurements. Finally, The rating of sound insulation (Rw) defined by JIS A1419-1 (ISO-717) was introduced, and the relationship between Rw and the characteristics of the gases between walls was investigated. The results indicate that gas with a low molecular weight and large ratio of specific heat is more effective to increase the TL.
著者
広瀬 通孝 石井 威望
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.51, no.471, pp.3153-3158, 1985-11-25 (Released:2008-02-21)
参考文献数
6
被引用文献数
3

A quantitative method to analyze mental work, such as programming or CAD operation, is discussed. The authors are proposing to define an index, named 'RRV', which is a variance of interval between successive R-spikes in E.C.G.(Electro Cardio Graph). In order to increase the measurement efficiency of RRV and to extend the time range of the measurement, a simple and handy-sized measuring unit is developed. From the result of experiments, it is proved that RRV is strongly connected with the condition of mental work. Under such intensive mental work as repetitive calculation for a long time, the value of RRV of the worker becomes lower than that under usual mental work. In addition, other basic characters of RRV, for example, the time-scale of its dynamic behaviour, are studied. Lastly, as a practical application, RRV is measured during computer programming, and several interesting phenomena are observed.
著者
北山 哲士 山川 宏
出版者
日本機械学会
雑誌
日本機械学会論文集C編 (ISSN:03875024)
巻号頁・発行日
vol.67, no.653, pp.9-16, 2001-01-01

金沢大学工学部
著者
佐藤 運海 竹ノ内 敏一 原 宏 山崎 隆夫 若林 信一
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.71, no.710, pp.3074-3080, 2005-10-25 (Released:2011-03-04)
参考文献数
7
被引用文献数
8 8

This paper describes development of end milling of carbon steel by electrolyzed reduced water of dilute sodium chloride solution, instead of conventional cutting with cutting fluid which is not environmentally consciousness. First, experimental equipments were built with a machining center, cutting fluid supply system made from the bath pump, temperature sensor and temperature recorder etc., and end milling processing of carbon steel was performed using electrolyzed reduced water of dilute sodium chloride solution and conventional cutting fluid respectively. Next, measured surface roughness, evaluated surface deterioration layer, temperature change of work piece and wear state of end milling. As the results of all evaluations above-mentioned, there is no difference between the end milling process using electrolyzed reduced water and that of conventional using cutting fluid. It is supposed electrolyzed reduced water instead of cutting fluid is environmentally consciousness process.
著者
横山 誠 Hedrick J.K. 外山 茂浩
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.67, no.657, pp.1449-1454, 2001-05-25 (Released:2008-02-26)
参考文献数
11
被引用文献数
8 8

This paper presents a new sliding mode controller based on the theory of model following control for semi-active suspension systems with Magnetorheological (MR) dampers which have undesirable nonlinear properties. In the proposed controller, a desired semi-active suspension system is chosen as the reference model to be followed, and the control low is determined so that an asymptotically stable sliding mode will occur in the error dynamics between the plant and the reference model states. The advantages of the proposed controller are : (1) measurement of the damping force is not required, (2) the reference model specifies the desired performance considering the passivity constraint of the damper, (3) it is highly possible to maintain the sliding mode and achieve high robustness against the nonlinear properties of the damper. Numerical simulations illustrate the effectiveness of the controller.
著者
安田 仁彦 神谷 恵輔
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.55, no.515, pp.1609-1615, 1989-07-25 (Released:2008-02-21)
参考文献数
21
被引用文献数
1 1

As a basis for developing an identification technique of nonlinear distributed systems based on their dynamical responses, an identification technique is proposed based on a simple example of nonlinear distributed systems. The example taken up is a simply supported beam vibrating with large amplitudes. The basic procedures of the proposed technique are: (1) measuring periodic responses of the beam to periodic excitations; (2) determining modal coordinates using the responses based on the modal functions of the corresponding linear beam; and (3) determining the modal equations including nonlinear terms using the principle of harmonic balance. Some numerical examples are given, and the technique proposed is shown to be applicable.
著者
山田 崇恭 西脇 眞二 伊賀 淳郎 泉井 一浩 吉村 允孝
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.75, no.759, pp.2868-2876, 2009-11-25 (Released:2017-06-09)
参考文献数
21
被引用文献数
1 2

In structural designs considering thermal loading, to control thermal stress and minimize decreases in material strength at high temperatures, it is important to maximize the thermal diffusivity of structures, in addition to the usual maximization of stiffness that optimal designs achieve. This paper presents a new level set-based topology optimization method for thermal problems with generic heat transfer boundaries in a fixed design domain that includes design-dependent effects, using level set boundary expressions and the Finite Element Method. First, a topology optimization method using a level set model incorporating fictitious interface energy is briefly discussed. Next, an optimization problem is formulated using the concept of total potential energy to address the design of mechanical structures that aim to minimize the mean temperature of the structure under thermal loading. An optimization algorithm that uses the Finite Element Method when solving the equilibrium equation and updating the level set function is then constructed. Finally, several numerical examples are provided to confirm the utility of the proposed optimization method.
著者
山崎 容次郎 横川 隆一 積際 徹 原 敬
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.74, no.740, pp.867-875, 2008-04-25 (Released:2011-03-04)
参考文献数
17
被引用文献数
2 4

This paper proposes a new switching method of control mode for a robot manipulator coming in contact with environment that has elasticity. First, the basic concept of the switching of the control mode in a robot manipulator is explained. Second, we propose a new method of switching the control mode that selects the control mode at the intersection of “Characteristic curve of position and force” and “Target value of the work composed by the desired value of position and force”. Next, the switching algorithm based on this method is obtained about a certain work coordinate with a Multi-DOF robot manipulator. In this paper, the switching method is named “A Method for Switching Control Mode Based on Position and Force Errors”. Furthermore, when a One-DOF robot manipulator driven by DC servo motor with reduction gears using an elastic joint came in contact with the object that has elasticity, the simulation and the experiment on various angle and torque controls were done. As a result, it is shown that the proposed switching method is useful and has stable and flexible characteristics.
著者
大西 厳 木村 一郎 山田 英巳
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.65, no.635, pp.2787-2793, 1999-07-25 (Released:2008-02-26)
参考文献数
13
被引用文献数
2 3

Recently, we have been demanding products that satisfy personal tastes. In these days, it is extremely important to make a human sensibility model and then build up a technology system for applying human sensibility to various fields in engineering. In this paper, a human sensibility model for musical chords is studied. The model that uses an artificial neural network is constructed by ccnsidering the structure of a cochlea that analyzes sounds into frequency. The musical chords that are composed of three or more musical tones are inputted into the neural network, and a set of the sensibility information that characterizes "cheerfulness-gloominess", "thickness-thinness" and "stability instability" is outputted. After training the model, the following results that agree with the knowledge of psychology and physiology are proved. 1) Some hidden units for "cheerfulness- gloominess" and "stability instability" are influenced by the critical bandwidth of musical tone frequency, and furthermore they have "Tonality". 2) For "thickness thinness", there is a unit that distinguishes musical tones by frequency.
著者
柴田 信一 曹 勇 福本 功
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.71, no.707, pp.2414-2419, 2005-07-25 (Released:2011-08-16)
参考文献数
9
被引用文献数
2 1

Bending modulus of elasticity of the composite material from bagasse fiber (remains after sugar cane squeezed) and biodegradable resin was investigated in view of the content of bagasse fiber and the fiber length. The result was validated by short fiber strengthen theory. The result is as followings. Bending modulus of elasticity increased with increasing the content of bagasse fiber. The increase of Bending modulus of elasticity is predicted by short-fiber strengthen theory incorporated with the compression ratio of bagasse fiber, which has honeycomb structure in the cross section, was compressed in press forming, makes good agreement with the experimental result. Bending modulus of elasticity decreased when the fiber length of bagasse is under 3 mm (aspect ratio=12). This result makes good accordance with the prediction value by the short fiber strengthen theory.
著者
斉藤 俊 千葉 洋三
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集C編 (ISSN:03875024)
巻号頁・発行日
vol.64, no.623, pp.2389-2394, 1998

Two kinds of road racer bicycles are employed to research vibration characteristics of driving bicycles. After obtaing the natural frequencies and modes by vibration test in the non-driving state, practical driving tests are carried out. The acceleration of vibration in the middle of the handles and under the saddles are measured and the corresponding spectral density functions are calculated based on FFT method. The results show that in the driving bicycles, the dominant frequencies exist between 10 Hz and 50 Hz and the lower two modes in the non-driving state are excited.
著者
肥爪 彰夫 倉田 健二 中村 優一 松田 隆男
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集C編 (ISSN:03875024)
巻号頁・発行日
vol.58, no.554, pp.2869-2876, 1992
被引用文献数
1

Excessively large transient torsional vibration is induced on the rotor system of modern large turbine-generators. This paper reveals that the coupling connecting the adjacent rotors acts as a hysteresis damper, and discusses the effect. First, a model is presented for the damping mechanism of typical shaft coupling. Second, the time-dependent nonlinear transient torsional vibration of the rotor system is investigated, using this model. Third, an improved coupling of higher damping capacity is introduced and investigated in the same way. Thus, the proper direction of the optimal design of coupling is clearly specified.
著者
野島 武敏
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.66, no.647, pp.2463-2469, 2000-07-25 (Released:2008-02-26)
参考文献数
8
被引用文献数
4 5

The aim of this paper is to invent foldable (or developable) conical shells in their axial direction. Foldable conical shells with several different types of folding patterns have newly been designed by geometrical considerations with the help of Origami concept. By using thin polypropylane sheet as well as papers, the designed conical shells with prescribed folding lines were actually manufactured, and it was verified that the shells are fully folded as expected. The designed models will make it possible to construct foldable/developable structures such as tents and dome-roof or to manufacture new types of industrial products.
著者
山本 普康 井上 剛 加藤 治 南田 勝宏
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集C編 (ISSN:03875024)
巻号頁・発行日
vol.65, no.631, pp.1255-1260, 1999

The surfaces of roll material were dulled by Nd-YAG laser machining under some conditions of focal length cooling and number of beams for laser irradiation, and the rolling and sliding wear experiments were made in order to investigate the wear resistance of crater rims formed on the dulled surfaces. Then, the effects of distances from a focusing lens to a roll material, cooling conditions of air and water and combined irradiation of 2 beams on the wear resistance of crater rims were clarified. As a result, it has been found that the condition of 1 beam irradiation, water cooling and appropriate focal length is the best for the wear resistance of crater rims in the present series of experimental conditions.
著者
田中 裕久 大石 保徳
出版者
The Japan Society of Mechanical Engineers
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.65, no.637, pp.3804-3810, 1999
被引用文献数
1

A double cavity half toroidal contimlously variable power transmission transmits input torque through a pair of variable units and changes its speed ratio by controlling attitude angels of four power rollers. One power roller among them is controlled by a hydraulic servomechanism and the others are followed it under the control principle of equal force transmission. Synchronization of four power rollers is guaranteed by safety wires, however nonlinearities of friction force on the control pistons or pressure delay in hydraulic lines due to air mix or pipe length cause instability of the speed ratio servomechanism through the safety wires. This paper focuses the relation between the synchronization and stability of the CVT by making bond graph analyses and experiments, and shows design guidelines on the stabilization of the double cavity half toroidal CVT.
著者
井上 卓見 末岡 淳男
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集C編 (ISSN:03875024)
巻号頁・発行日
vol.66, no.644, pp.1074-1081, 2000

The authors present a new step-by-step integration scheme by utilizing the cardinal B-splines. The new method organizes conventional implicit methods such as Newmark-β method and Wilson-θ method and so on, and provides a simple computation procedure so that the step-by-step integration can be carried out efficiently. In addition, when we analyze a nonlinear system with discontinuity the computational acuuracy can be improved by the approximate detection of the points of discontinuity by making good use of the two-scale relation. In this paper, we formulate an algorithm of a time historical response analysis of a straight-line beam structure as an elementary example of multi-degree of freedom system besides a simple single degree of freedom system. The cardinal B-splines used here are only the ones of orders 3 and 4 but the other cardinal B-splines are also available for step-by-step integration in the same way.
著者
谷 泰弘 金 泰元 澤山 翔 蔦中 孝丞 山口 幸男 佐藤 康治
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.76, no.762, pp.453-458, 2010
参考文献数
5

In order to reduce the costs in wheel manufacturing and on usage of the wheels, we investigated the method of adjusting the sharpness of grinding wheels by using heat treatment and UV treatment. At first it was confirmed that heat treatment of phenol resin grinding wheels for aluminum in a furnace enabled to improve the grindability of stainless steel and to prevent swarf loading. Next it was made clear that surface treatment of grinding wheels by using UV irradiation and hot air blowing had the similar effect with the heat treatment in a furnace. These treatments reduced the force ratio in surface grinding. In these cases the affected layer was limited to the wheel surface though heat treatment in a furnace affected the whole wheel. The thickness of the layer varied with the UV irradiation time. At last we applied this technique to other resinbond wheels and the same effect was obtained for the wheels with polyester bond. However heat treatment did not improve the grindability of epoxy bond wheels with high heat resistance. In such case UV treatment was an effective method to activate flow-out of swarf.
著者
野中 俊昭 大山 忠夫 遠藤 靖典 吉川 広
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.71, no.705, pp.1604-1610, 2005-05-25 (Released:2011-03-04)
参考文献数
14
被引用文献数
1

Dynamic behavior of train sets on railways during braking can be regarded as the combination of the translation and the rotation. That is, both the kinetic energy for the translation of train sets and the one for the rotation of each axle are decreased to zero as the braking force and the adhesion force of each axle have an effect on each other. However, dynamic models for brakes of train sets have been hardly represented and discussed. Furthermore, a reduction of wheel damages has never been evaluated for control performances of Anti-lock Braking System (ABS), in spite of one of the most important aims of ABS. In this paper, we propose a dynamic model for brakes of train sets consisting of n axles and an equation for evaluating wheel damages. And we show that the proposed model and equations are useful to evaluate the control performances of ABS for train sets.
著者
吉澤 正彦 景山 一郎
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.71, no.702, pp.541-546, 2005-02-25 (Released:2011-03-04)
参考文献数
4

This paper focuses on the tire force characteristics related to the vehicle speed. We constructed a mechanical tire model using a Voigt-Type viscoelastic spring system for the tread rubber. And, we analyze the force distribution along the contact length, the dependence of vehicle speed to the tire forces and the moments to a change in sideslip angle. Finally, it is shown that the tire model has good agreement with actual measurements results qualitatively, and also it is found that the characteristics of lateral force have independence to the vehicle speed.
著者
和田 憲造 藤本 康之 早野 延男 埴谷 和宏
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 C編 (ISSN:03875024)
巻号頁・発行日
vol.56, no.524, pp.935-940, 1990-04-25 (Released:2008-02-21)
参考文献数
4
被引用文献数
3

The screw feeder is extensively used as a feeder of granular materials. Until now, a few reports regarding the fundamental characteristics of the screw feeder, for example, the required power and the quantity of discharge from the feeder, have been published. However there are almost no reports on the dynamic characteristics and the transportation mechanism. In this paper, the transporting state and the transportation mechanism of granular materials inside the screw feeder are investigated. First, the effects of the rotating speed of the screw shaft and the pressure of granular materials inside a feed hopper on the required power and quantity of discharge are examined. Secondly, the transporting state of granular materials inside the screw feeder is investigated. Then the transportation mechanism is discussed by analyzing the motion of a tracer inserted into the screw feeder and by using a velocity diagram.