-
Motomu YOKOMORI, Shigeki YAMAGUCHI, Masakazu KAMIYAMA
Article type: Article
Pages
295-296
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
The paper deals with the movements of man-motorcycle system to prevent the accidents in the straight running. We studied on the behavior of motorcycle reducing speed in case that the motorcycle unsuccessfully stops before the obstacles or successfully passes through it, by means of the virtual mass. Furthermore we examined the psychological influence in this case on a rider.
View full abstract
-
Motomu YOKOMORI, Shigeki YAMAGUCHI, Masakazu MURAKAMI
Article type: Article
Pages
297-298
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
A driver is loaded psychologically and physiologically by the moving cars and the cars parked at the side of road that comes into the front view. Thus, the driver is subjected to mental stress which depends on the change of obstacles above mentioned, and the stress usually causes a change in the physiological conditions of driver. The traffic accidents are caused when these influences put a lot of stress on a driver. From this stand point this paper examines relations between the road traffic condition and the driver's psychological and physiological responses by using the driver's field of vision and sweating.
View full abstract
-
Kunio Fukuyama, Nobuyuki Uchida, Kazuo Fujita, Tsuyosi Katayama
Article type: Article
Pages
299-300
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
The present in-depth study investigated causative factors of un-signalized intersection accidents with good visibility. The causative factors of sixteen cases was analyzed from the points of road environment, vehicle condition and driver's recognition. It was shown that driver's recognition and/or detection errors were principal causes of this type of accidents, especially for the drivers approaching on subsidiary road. The relation between recognition/detection performance of peripheral vision and two vehicles' relative position was discussed.
View full abstract
-
Yasuo WATANABE, Susumu KUMAKURA, Kenichi MAEMORI
Article type: Article
Pages
301-302
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
In this paper, we present an optimum design method of suspensions for ambulances and vibration-isolation beds for reducing jolts experienced by patients when ambulances pass over a combined speed hump and pedestrian crossing. As a result of the optimum design of the suspensions, the optimum dampers and the optimum air springs of each of the ambulance and vibration-isolation bed suspensions are obtained and the jolts are reduced.
View full abstract
-
Takao HIGASHIMACHI, Takahide NAKAYAMA, Takenori HIRAKAWA, Hisato SASAH ...
Article type: Article
Pages
303-304
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
As the part of universal gripper development which holds piston ring of various diameters in 6 nails, the deformation behavior of piston ring in robot arm tip holding part was clarified, and adaptability evaluation of the hold mechanism was carried out. The aspect of the deformation in concretely holding piston ring in multiple supporting point was analyzed by the finite element method, and the relationship between deformation characteristic and retention force and hold method was clarified. On the basis of these analytical result, whether it was effective for the piston automatic insertion to the cylinder in respect of the deformation without the irrational in piston ring was investigated, and development support of the multiproducts-correspondent hold mechanism was carried out what kind of hold mechanism.
View full abstract
-
Keiichi WATANUKI, Hideyuki OHTAKI
Article type: Article
Pages
305-306
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Mechatronics systems are hybrid systems, which consist of mechanical system, electronic device, control system, computer software, and so on. For demands of higher precision and function enhancement, mechatronics systems have required parallel operation and cooperative control. This paper proposes a UML (Unified Modeling Language)/Petri net method for modeling and analysis of a mechatronics control system. Based on our UML/Petri nets representation, it is possible to generate the control program automatically. We have conducted simulations and confirmed that the proposed method UML/Petri nets is useful for control system analysis of mechatronics system.
View full abstract
-
Hiroshi YAMAKAWA, Hiroshi HOSAKA, Kiyoshi ITAO
Article type: Article
Pages
307-308
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
A simple and accurate system to measure structural damping coefficients was investigated. Measurement requirements were derived after studying airflow damping and energy dissipation at supporting points. Structural damping coefficient was measured using lasor doppler vibrometer and FFT analyzer. As a result of measurement, the measurement system was validated for measuring structural damping coefficient. However, the system was uneconomical because of the high cost. So a new system was developed using a microphone as a vibration sensor and a personal computer for signal processing. Compared with the previous system, it was only about 1/10 the cost of previous system, almost the same measurement accuracy was obtained, and measuring time was reduced to less than 1/10 that of the previous system. From these results, the new measurement system was validated for simple and accurate measuring of structural damping coefficients.
View full abstract
-
Kaoru UCHIDA, Shigeki TOYAMA
Article type: Article
Pages
309-310
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
The main purpose of this research is to develop a mathematical model for human walking motion. We analyzed human walking motion and found that the ZMP (Zero Moment Point) plays an important role. Then, we actually have measured human walking motion precisely and have made sure of that walking mechanism. Based on that mechanism, we have developed the mechanical model and have simulated human walking motion using this model. As a result, we will be able to build the optimal walking pattern.
View full abstract
-
Kenichi KIKUCHI, Yuiti NAKAZATO, Yukinori ARIGA
Article type: Article
Pages
311-312
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
In this study, self-organization robot system the research development in the single robot, by separating the robot of multiple units, and combining, and cooperating, self-organization robot whom it defines in this study makes it to be whole system which enables impossible done work. Therefore, basic configuration element and transfer method of the self-organization robot system are proposed. The basic configuration element of which the deformation was solidly possible actually was produced, and the verification was carried out experimentally. And, the transfer using this deformation mechanism is carried out as the mechanism that it adds the deformation mechanism at the basic configuration element and can carry out the shape change.
View full abstract
-
Yuiti NAKAZATO, Kotaro ADCHI, Yukinori ARIGA
Article type: Article
Pages
313-314
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
The shape memory effect of SMA is the phenomenon which originates from the change of crystal structure with phase transformation. Therefore, the operation speed is dependent on heating and cooling speed. The heating of SMA is carried out comparatively at high speed by direct sending of electricity. However, the decisive method on the cooling not view the place in of today. Because of the above, it becomes the hindrance in speeding up operation speed of the SMA actuator. In this study, it is to made to move in the material of which thermal conductivity such as the oil is high in respect of SMA, and it raises the cooling efficiency, and the operation speed is improved. In addition, the system for the power transmission by generated hydraulic pressure is reported, because it was developed.
View full abstract
-
Shinnosuke TORII, Daiki KAMIYA, Mikio HORIE
Article type: Article
Pages
315-316
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
In order to reduce the output errors of micromechanisms, our study has suggested the use of new micro-hinges with a rigidity that has been made suitable enough to decrease the differences between the hinge end locus and the circular locus. Based on this, we have conducted theoretical analyses, while at the same time creating micro-hinge models using a semiconductor minute processing technique for our experiments. Afterwards, we will discuss and study the effectiveness of the use of the suggested micro-hinges, through comparisons with conventional shaped micro-hinges.
View full abstract
-
Koichi TAKAHASHI, Daiki KAMIYA, Mikio HORIE
Article type: Article
Pages
317-318
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
In this paper, the force sensitivity of the finger is investigated experimentally to develop the good maneuverability human interface. To investigate the force sensitivity of the finger, the upper limen is measured by using two methods. The first method is that the acting force to the finger is constant. The second method is that the acting force to the finger is continuously increased. In the results, the upper limen of the acting force to the finger becomes greater with an increase of the standard acting force to the finger. This study contributes to the improvement of the maneuverability of human interface in the force control feedback systems.
View full abstract
-
Daiki KAMIYA, Koichi TAKAHASHI, Mikio HORIE
Article type: Article
Pages
319-320
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
The purpose of this study is to clarify the specification required for the force feedback master manipulator that a human operates without a feeling of wrongness. We measure the motion of human hands and the grasping force with two CCD cameras and load cells attached to the objects respectively when the human grasps two types of objects different from one another in grasping length and weight. Bending and stretching of the three joints of the forefinger is dominant to the motion of the forefinger, and the tip of the forefinger moves within a plane. The tip of the thumb moves within a plane too, however the slope angles of the plane differ according to the subject. At the beginning of a grasp the overshoot of the grasping force tends to arise because of the inertia force of the object when the object is lifted up suddenly. When the overshoot of the grasping force doesn't arise, the stabilization time of the grasping force is about one second.
View full abstract
-
Katsumi Watanabe, Hiroaki Katoh, Ying Xu
Article type: Article
Pages
321-322
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Nongrashof planar four-link mechanisms, that none of two neighboring links can make a complete rotation, generate complex coupler curves with highly nonuniform velocity when the driving link oscillates in such a manner that coupler and driven links belong to different composition loops in going and returning respectively. In this paper, for the poupose of classification and synthesis of nongrashof mechanisms, a procedure is presented for arranging points on the coupler curve with equal distance, in which the input and output angles are interchanged according to whether the differential coefficient of the output angle is greater than some reference values or not.
View full abstract
-
Ying Xu, Katsumi WATANABE, Hiroaki KATOH
Article type: Article
Pages
323-324
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Nongrashof Planar Four-link mechanisms generate complex coupler curves with non uniform velocity when the driving link oscillates in such a manner that coupler and driven links belong to different composition loops in going and returning respectively. In this paper, a pattern matching method is presented for synthesizing the coupler curves of the nongrashof mechanism, The method consists of magnification or reduction of the coupler curves, arrangement of equidistant points on ideal and coupler curves, one-to-one correspondence of points on both curves so that the norm of their natural equations may be minimized and coordinate transformation of the coupler curves so that the maximum difference between both curves may be minimized.
View full abstract
-
Jun NANGO, Katsumi WATANABE, Takayuki MORITA
Article type: Article
Pages
325-326
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
The direction of driven link of the spatial 7R 7-link mechanism is expressed by two angles in the case where three adjacent axes and two adjacent axes intersect a point respectively. Namely, the driven link can be connected by universal joints at both ends, so this type of mechanism has two output angles. It is difficult to simulate the output angle error using the method of sensitivity analysis, because it is needed that the simulation using the same value of deviation of the kinematic constants agrees with two output angle error, simultaneously. In this paper, we show that the simulation can be done appropriately assuming the functional relationship between the input angle and the deviation of kinematic constants, and that functional relationship concerns with the input moment and the motion transmissibility.
View full abstract
-
B. FENG, N. MORITA, T. TORII, Y. NAKAMURA, S. YOSHIDA
Article type: Article
Pages
327-328
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
A new mass distribution method is proposed in this paper for the balancing of the shaking force and the shaking moment in a high-speed spatial RSSR mechanism. The multi-objective function with the weighting factors is given, and GA (Genetic Algorithm) as the optimization technique is used. The numerical examples are included, and the results show that the new mass distribution method is effective for the balancing of the shaking forces and the shaking moments. The experiments made it clear that the vibrations of a machinery foundation can be reduced effectively by the balancing of the shaking forces and the shaking moments.
View full abstract
-
Eko PURWANTO, Shigeki TOYAMA, Kouichirou WATANABE
Article type: Article
Pages
329-330
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
This paper presents contact models of an ultrasonic motor using finite element method. The contact between a stator and a rotor, which is difficult to be performed at the experimental investigation, will be modeled using finite element solver called abaqus, which can solve contact problems by using finite element method. Since a pre-load given to a rotor plays an important role in this type of ultrasonic motor, contact models will be evaluated to examine either the change of friction forces or the displacement of the contact point due to the change of the pre-load given to the rotor. The results of this contact simulation will be shown and the validity of the models will be discussed.
View full abstract
-
Mitsuo KOBAYASHI, Michihiko TANAKA, Naotake NIWA, Kaoru HONGO
Article type: Article
Pages
331-332
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
The distribution of load in screw thread have very important effect on the strength of bolt and nut connections. It has long been reported that the distribution of load along the length of a nut for triangle is not uniform. And, the triangle thread has been usually in the bolted joint, however, others such as the buttress thread may be used for ensuring the tight-fastening of screw plug. Therefore, the load distribution has been investigated for the case where such the buttress thread is used for the bolted joint., and its influence on the load distribution has been examined in comparison with the triangle thread.
View full abstract
-
Shinji HASHIMURA, Yukitaka MURAKAMI, Akira KURODA
Article type: Article
Pages
333-334
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
The compressive force method for bolt tightening can be improved by finding the bolt head which has a constant frictional coefficient from the start to the end of tightening. Variations of frictional coefficient between bearing surfaces have been investigated on various bolt head types with different conic angles of bearing surfaces and with configuration error such as burr on the edge of bearing surfaces. It has been found that the bolt head type with +1° to bolt head and to outside has almost constant frictional coefficient and is expected to be the optimum head geometry. Tightening experiments have shown that the optimum one has the most accurate clamping force by the compressive force method.
View full abstract
-
Masao NISHIOKA
Article type: Article
Pages
335-336
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Precision machining is in greater demand with the recent development of faster industrial machines. Two simultaneous control axes of machine tools are commonly used for machining two-dimensional objects. This method has an inherent problem, however, the quadrant protrusions at specific area which deteriorate accuracy of the object can not be avoidable. This paper proposes a method wherein a circular is controlled as a redundant control axis such as to avoid quadrant protrusions. The relation between rotating angle of the circular and conventional spindle position are derived based on the direction of movement of the controlled axis by a graphical method. The effectiveness of this method was verified by simulations and actual machining tests.
View full abstract
-
Hidehiro YOSHINO, Fumihiro OHSHIMA
Article type: Article
Pages
337-338
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
A new vacuum screw pump available in oil free condition was developed. This pump is composed of two screw rotors and a housing to wrap them. The thread numbers of both rotors are 1 and 2 although the outside diameters are the same and the profiles of both rotors are conjugate to each other to make the completely closed tooth space among both rotors and the housing. Equations to calculate driving torque of both rotors and a theoretical delivery were derived. The vacuum pumps were experimentally made and the performance tests were carried out. When the 1-thread (male) rotor was rotated at 3600rpm, a vacuum below 2mmHg was obtained.
View full abstract
-
Hiroyuki SHIBUYA
Article type: Article
Pages
339-340
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
An evaluating map of rubber roller for flexible media handling system, which can describe an operating condition of each rubber roller for well handling of flexible media, is introduced using two design parameters for the handling system such as speed of driven flexible media and applied load between rubber roller and drive media. Potential and durability of rubber roller for flexible media handling system can be evaluated by a range of operating condition in this map. The usefulness of this map is proven by the experimental results observed by using handling system with rubber roller and paper.
View full abstract
-
Kazuki ICHIKAWA
Article type: Article
Pages
341-342
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
About the rolling spherical bearing consisting of a sun ball, planetary balls, retainers and sockets, the stiffness, eccentricity of the sun ball and static load capacity are calculated with consideration of the scattering of elastic deformation at each contact point due to the dimensional errors of the bearing components. Then, the effects of pre-load upon the stiffness and the eccentricity are discussed theoretically and experimentally. Furthermore, about a spatial in-parallel actuated mechanism with the rolling spherical bearings, its stiffness and position repeatability are improved by giving appropriate pre-loads to the bearings.
View full abstract
-
Atsushi KITAHARA
Article type: Article
Pages
343-344
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
In this research, we discuss the peculiar vibration behavior of a ground helical gear pair that appears at non-integer order of the meshing frequency. It is supposed that the vibration is generated because of the irregularity of tooth surface form whose cycles are different from tooth mesh cycle. We measured tooth surface from of all teeth of test gears with the coordinate measuring machine. And we processed the surface form in rotational order of a gear by spectral analysis. As a result, tooth surface irregularity that causes the peculiar vibration can be detected. Furthermore, we present the least measurement conditions that enable the detection of noninteger order of mesh vibration. It is useful for the quality check in manufacturing process.
View full abstract
-
Chikara YAMASHITA
Article type: Article
Pages
345-346
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
This paper describes effects of contact pressure, sliding speed and ambient gas on the friction properties of a-CNx coating sliding against Si_3N_4. Friction coefficient decreases with the increasing of the contact pressure, and reaches to very small value (μ=0.01∿0.05). Sliding speed affects the contact pressure dependency of fiction coefficient. Friction coefficient increases with the humidity. The best ambient gas for very low friction coefficient is N_2. And the most effective method to introduce N_2 (μ=0.003).
View full abstract
-
Atushi Matutani
Article type: Article
Pages
347-348
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
RB ceramics are hard porous carbon materials made of rice bran, and they have the superior tribological characteristics. In this investigation, new making method of RB ceramics "C-RBC/P" was proposed, and their tribological characteristics in various conditions were analyzed experimentally.
View full abstract
-
Hirokazu KURITA, Takashi NAKAMURA
Article type: Article
Pages
349-350
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
This paper describes machining properties of an oil on water machining fluid which is newly developed for the environmental issues. Comparatively large size water drops are covered with vegetable oil film and sprayed on a machining point with soft air jet in milling processes. In the machining tests, temperature rises and machining accuracy of products are measured and compared with flood emulsion and oil mist coolant systems. Experimental results show that the machined product with oil on water machining fluid has a sufficient accuracy nearer to that with flood emulsion coolant system.
View full abstract
-
Tadashi SAITOH, Shojiro MIYAKE, Shuichi WATANABE, Hiroto HARA
Article type: Article
Pages
351-352
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
In this study, tribological properties of high energy ion implanted diamond like carbon films were studied. Nitrogen ion implanted, dynamic mixing and static mixing DLC films show the lower friction and higher wear resistance than ion plated DLC film. The effects of DLC films deposited by plasma based ion implantation on tribological properties were insufficient.
View full abstract
-
Toshihiro OZASA, Shigeo SUZUKI, Takashi NODA, Toshiaki KONOMI
Article type: Article
Pages
353-354
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Oil flow rate to a con-rod big-end bearing was studied with theoretical and experimental approach. The Elrod's algorithm was applied to the mass conserving EHL theory with a simple model of oil flow in a passage. A hot film anemometer was calibrated and applied to the measurement of oil flow rate. The oil flow rate to con-rod big-end bearing in an experimental engine was calculated and measured under full load operations.
View full abstract
-
Takashi TOMIKAWA, Sigeyuki SUGA, Yasuaki GOTO
Article type: Article
Pages
355-356
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
The rotational speed of high performance gasoline engines is getting higher. The overlay of bearing is used at more higher temperature caused by high rotational speed. As the result, the overlay is given different damage from conventional type. It is the overlay peeling caused by melting intermetallic compound at Ni layer boundary. So, we developed the new overlay material that makes no low melting point intermetallic compound. The overlay consists with lead, tin, indium and copper. Copper suppresses diffusion of tin and indium in lead for no low melting point intermetallic compound.
View full abstract
-
Tadashi SAITOH, Shojiro MIYAKE, Shuichi WATANABE, Makoto KANOU, Yoshit ...
Article type: Article
Pages
357-358
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
To improve the lubrication properties of DLC coated sliding parts, various metals such as molybdenum (Mo), tungsten (W), iron (Fe) and titanium (Ti) are contained to DLC films. DLC coating without metal show little effect on lubrication properties with EP (Extreme-Pressure) additives, however the friction coefficient of metal containing DLC films decrease gradually with sliding cycles due to EP additives.
View full abstract
-
Takashi NAKAMURA, Tomio MATSUBARA, Fumihiro ITOIGAWA, Yuichiro TAI
Article type: Article
Pages
359-360
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Alternative refrigerant HFC-134a is now used as a refrigerant gas for the automotive air conditioning system. Friction properties in ammonia and carbon dioxide gases, which are regarded as coming alternative refrigerants, are examined to compare with that of HFC-134a. The experimental results of pin-on-disk type friction tests in them show that the seizures between the pin and the disk occur frequently in starved lubricating conditions and that the surface treatment such as Sn plating improves the tribological properties.
View full abstract
-
Yuichi NAKAMURA, Tetsuki FUJIOKA, Yasushi KUROSAKI
Article type: Article
Pages
361-362
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
In order to grasp basic high-pressure traction characteristics of automobile toroial CVT transmission, a traction testing machine up to 4.5 GPa of maximum Hertzian pressure was established. Considering pressure increase with decreasing radius of curvature in rolling surfaces, small balls of rolling bearing were assembled whose diameter is 20mm. Established testing machine was compact and enabled the pressure generation up to 4.5 GPa (3 GPa mean pressure) applying only 980 N (100kgf) force, and traction force was measured by load cell (in stead of torque measurement) in link loading mechanism. Some experiments were made and maximum traction coefficients and initial slopes in traction curves were investigated.
View full abstract
-
Jun WATANABE, Kenshi USHIJIMA, Toshikazu OSHIDARI
Article type: Article
Pages
363-364
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
It is essential to ascertain traction characteristics under actual operating conditions in order to apply a toroidal CVT incorporating a traction drive system to automobiles. This paper first describes the traction characteristics obtained quantitatively over a wide range of conditions by using a 4-roller tester. Furthermore, an attempt was made to obtain the rheological parameters of the fluid by using Evans's isothermal test. The resulting parameters were input into a viscoelastic-plastic model, and a comparison was made between the calculated results and the 4-roller test results. It was found that an accurate prediction of traction characteristics requires the above-mentioned model and consideration of rolling element temperature.
View full abstract
-
Kenshi USHIJIMA, Jun WATANABE, Toshikazu OSHIDARI, Shunichi AOYAMA
Article type: Article
Pages
365-366
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Implementing a toroidal CVT, in which driving force is transmitted by traction drives, in a production vehicle requires knowledge of traction characteristics under actual operating conditions. A mathematical model was developed to calculate traction characteristics, taking into account spin and side slip and using the rheological parameters measured for the fluid in cylinder tests. The calculated results obtained with the model indicate that temperature has a significant effect on traction characteristics under actual usage conditions. A model that can simultaneously treat viscoelasticity and elastoplasticity is therefore needed to calculate the effects of temperature accurately.
View full abstract
-
Hirotsugu HAYASHI, Hitoshi FUKASAWA
Article type: Article
Pages
367-368
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
In this paper, the effects of Bingham viscoelastic rheology characteristics of lubricants on the performance of inclined step thrust squeeze bearings are clarified on the base of the modified Reynolds equation for the fluid film lubrication derived by considering the core formation due to both Bingham and viscoelastic characteristics.
View full abstract
-
Tomio MATSUBARA, Takashi NAKAMURA, Fumihiro ITOIGAWA, Yoshiaki NAGATA, ...
Article type: Article
Pages
369-370
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
A hybrid journal bearing in which the hydrodynamic and hydrostatic pads were alternatively provided on an identical circumference in order to utilize the excellent damping and stability characteristics of a journal bearing was proposed for a high-speed spindle. As a test result, the temperature rise of the hybrid journal bearing was lower than 1.5K at DN value up to 720000 (Diameter; 60mm, N; 12000rpm). Load carrying capacity, bearing rigidity, and power loss of the hybrid journal bearing were also measured in the experiment. The all value obtained were resulted in fairly good comparing with a conventional journal bearing. From this study, the possibility of a hybrid journal bearing for more high-speed spindle was shown.
View full abstract
-
Kenji SUZUKI, Yurika UYEDA
Article type: Article
Pages
371-372
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
A friction torque measuring device for microbearings was developed. Journals with 280μm in diameter, and sliding bearings with 300μm bore in diameter were used for the measurements. Three kinds of bearing materials and two kinds of lubricants were prepared to examine these effects. In cases of bearings with mineral oil (ST5) and without lubricants, fluctuation of friction torque occurred because of contact between the journal and the bearing. The experimental results show that lubricant with low viscosity such as OMCTS is useful to reduce friction and wear of microbearing.
View full abstract
-
Katsumi IWAMOTO
Article type: Article
Pages
373-374
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Ruuber has recently been installed in the structure of some bearing in order to suppress the vibration of rotors. One such example is the swing pad bearing. It consists of some segmented pads supported by curved laminates of rubber and metal. The pads tilt according to the deformation of the rubber caused by the rotation of the shaft. Inspite of its self aligning and good stability characteristics, the application of swing pad bearing has been rare in actual machine because of expensive cost of manufacturing due to its complicated configuration. Therefore, the improvement of structure is demanded in swing pad bearing. In this study, simplified swing pad bearing, which has pads supported by only one layer as shown fig.1,have been conside
View full abstract
-
Kenji Suzuki, Tetsuji Dohi
Article type: Article
Pages
375-376
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Friction force between a diamond pin and a silicon wafer which was vibratedin x, y or z direction was measured under low load conditions. A silicon wafer with PFPE lubricant on its surface was also tested to examine the effect of ultla-thin liquid film. In the case of the wafer without lubricant, the friction coefficient decreases with increase in amplitude or frequency of the vibraion in any direction. On the other hand, in the case of the wafer with PFPE lubricant vibrated in z direction, the friction coefficient increases at lower frequency and smaller amplitude, and decrease at higer frequency and larger amplitude, which is peculiar to the microscale friction. These results suggest that microscale friction can be controlled actively using surface vibration and thin liquid films.
View full abstract
-
Yoshiro IWAI, Seiichi NISHIKITA, Tomomi HONDA, Takaaki ONIZUKA
Article type: Article
Pages
377-378
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Tribological properties of PEEK and a carbon fiber filled PEEK composite (CF-PEEK) were studied by rubbing them against a steel counterface at a load of 300-1500N and a velocity of 1.0m/s under oil-lubrication. The friction coefficient and wear rate of CF-PEEK were almost the same as contact load increased. The wear rates of both PEEK and CF-PEEK under high contact load conditions were much lower than those of WJ2 and CAC603. It was found that filling of carbon fiber with PEEK improves the wear resistance as well as load resistance and heat resistance.
View full abstract
-
Yuugo MUKAI, Isamu TSUBONO, Isao HAYASE, Masaki KOYAMA, Koichi SEKIGUC ...
Article type: Article
Pages
379-380
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Leakage flow through a narrow clearance in a scroll compressor consists of oil mixed with refrigerant gas. We experimentally and theoretically studied the leakage characteristics of refrigerant R410A and POE oil through the narrow clearance. To do this we developed an apparatus with a channel having a narrow clearance to test the leakage characteristics. And a separated-flow analytical model revealed that multiphase flow of refrigerant R410A and POE oil does not corresponds to the measured leakage characteristics.
View full abstract
-
Masaki KOYAMA, Isamu TSUBONO, Kazutaka WATANABE, Kouichi SEKIGUCHI
Article type: Article
Pages
381-382
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
We measured the friction force on the bearings in a scroll compressor, then investigated the effects of dissolving refrigerant in the lubricating oil on the frictional characteristics. By comparing the experimental coefficient of friction with the theoretical one, we estimated the effect of dissolving refrigerant on oil's viscosity and on the coefficient of friction.
View full abstract
-
Akiyoshi KOBAYASHI, Yoshifumi KURATA, Noriyuki CHIKAGAWA
Article type: Article
Pages
383-384
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Surface generation mechanism by burnishing action in machining process has been examined experimentally and theoretically. Experiments were carried out based on the observation of the plastic deformation process of one amplified triangular column made of pure lead under very slow burnishing speed. The plastic flow to the orthogonal direction obtained from the observations agrees approximately with the theoretical values by Hill.'s plastic theory. The plastic flow to the forward direction was also observed. The forward deformation depends on the degree of the interference between the relief surface of the tool and the specimen. The forward deformation was also caused by the relief part of cutting edge radius.
View full abstract
-
Isami NITTA, Takashi Hasegawa
Article type: Article
Pages
385-386
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
-
Katsumi FUKUDA, Takashi NOGI, Takahisa KATO
Article type: Article
Pages
387-388
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
Contact between a specimen and an indenter in the nanoindentation hardness test is analyzed by using the Greenwood-Williamson model. The specimen and indenter are approximated by an elastic rough surface and a rigid smooth surface, respectively, and roughness parameters of topographical data obtained from real hardness indentations are used. Variation of Ar/An, the ratio of real contact area to nominal contact area, with the indentation load and surface roughness of the specimen is investigated. The results show that Ar/An tends to increase as the load decreases while the roughness has no significant effect on Ar/An.
View full abstract
-
Tomomi HONDA, Yoshiro IWAI, Yoshiro NISHITA, Hideo NAKAJIMA
Article type: Article
Pages
389-390
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
The pull-off force were measured by using AFM with various curvature radius of a spherical probe in air under the relative humidity controlled. The curvature radii were 8,11,16μm. The tests were performed with four kinds of test specimen (single-crystalline <111> silicon, PTFE, and two super-water-repellent coating film). Pull-off force of silicon increased with increasing relative humidity and curvature radii. On the contrary, the pull-off force of super-water-repellent coating film with large contact angle was independent of relative humidity and curvature radii. From these results, it is found that the influence of the meniscus force by the adsorbed water on the pull-off force is reduced with the super-water-repellent coating film.
View full abstract
-
NaoAki NODA, KenIchiro TAKEUCHI, Masato Nagawa, Fumitaka SHIRAISHI, Hi ...
Article type: Article
Pages
391-392
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
This paper deals with a new seal system between two flanges without using gaskets. The system includes a groove and an annular lip that is held by one of the flange with its highest point in contact with the other flange to form a seal line when the flanges are assembled. The critical internal pressure for leak in the sealing performance of this system is investigated through an experiment and FEM analysis with varying flange nominal size. The analysis indicates that the critical pressure is controlled by the maximum contact stress appearing at the highest point of the annular lip when the flanges are assembled even the flange nomimal sizes are different.
View full abstract
-
Shizuo ISHIZUKA, Genshiro OU
Article type: Article
Pages
393-394
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
RESTRICTED ACCESS
This research deals with the influence of the surface roughness on the friction properties for a hard hemispherical projection of the radius of curvature r sliding on a smooth soft surface or a soft one with the hemispherical projections of the radius of curvature R. This paper is examined on the effects of various factors on the relationship between the indented depth and the friction coefficient. The friction mechanism between the hard hemispherical projection of the radius of curvature r modeled on the asperity of a hard material surface and the soft surface has been theoretically analyzed taking into consideration with the frictional resistance caused by the ploughing and shearing term. The results of numerical examples based on theoretical analysis can be expressed as follows. The friction coefficient for the smooth soft surface increases with the increase of a contact angle that obtains from the radius of curvature r and an indented depth λh of the hemispherical projection.
View full abstract
