As a problem about elevator, it is concerned that vibration generated in elevator traction machine transmits to the adjacent room through the beam of building. Therefore, base supports elevator traction machine with vibration isolator is installed to resolve the problem. However, many isolators are used for elevator traction machine base to guarantee much of safety in some cases. Hence, the purpose of this study is to select the most suitable vibration isolator and suggest the design of framed structure can provide a high damping effect. In previous study, some experimental devices in imitation of an actual machine were made. Furthermore, vibration experiment and consistency verification were carried out. Consequently, good simulation results were obtained. However, it was necessary to identify various parameters by making trial and error in the process of modeling. This paper proposes a systematic parameter identification method. Unknown parameter is spring constant of bolt joint. In addition, if dimensions of bolt were same, we verified the value of spring constant almost accorded in multiple models.

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In recent years, super-high-speed elevator is required with increasing skyscrapers. However, it is nearly impossible to verify the travel performance such as a horizontal vibration of super-high-speed elevator, because the enormously long elevator shaft is needed. Therefore, a simulation model of the elevator is needed for verifying the horizontal vibration; in addition, the simulation result is required to the same accuracy as a result get by using actual elevator. In this study, we have constructed the simulation model that can change the main components of an elevator freely, can simulate the horizontal vibration of an elevator with high accuracy at any traveling speed.

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In the ultra-high-speed elevator, there is a possibility that the vibration of the car is increased by the fluid force generated when the car and the counter weight pass each other. Wind pressure generated during passing, because it increases in proportion to approximately the square of the elevator speeds, has become an important issue in the ultra-high-speed elevators. This paper, for the counterweight, to verify the effect of the fluid force reduction by providing additional and opening of the rectifying cover. In addition, as a result of fluid analysis and physical testing, we obtained the prospect that fluid force can be reduced about 30 percent of the time passing.

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In recent years, lifting distance of elevators to be installed in a building got longer due to high-rise building, thus elevator rope is longer. Therefore, the natural period of the elevator rope increases and gets closer to the natural period of buildings. As a result, the elevator rope hooked to the equipment of shaft when the rope vibrates by earthquakes. Therefore, secondary disasters such as entrapment and elevator service stop may occur, it has became a problem. For example, The Great East Japan Earthquake in 2011, 2125 cases of problems such as catch and damage of elevator ropes have been reported. In addition, rope entanglement and entrapment occur in high-rise buildings in Osaka, 700 kilometer away from the seismic center. Therefore, it is necessary to analyze the behavior of the elevator rope vibration. Each of manufacturers has own analysis techniques, but its key techniques are usually secret. Thus integrative comparison among various manufacturers is difficult. Therefore, the present study aimed at construction of the elevator ropes analysis model, which can be applied to any elevator. In this report, we investigate the behavior of elevator ropes of each tension and linear density.

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A vibration suppressor is used to change the natural frequency of an elevator rope, and to prevent resonance. The elevator rope is modeled using a string. However, the vibration of the string that has a vibration suppressor has been studied for a few conditions because of its geometric nonlinearity. An exact solution of the free vibration of a string with a vibration suppressor located at 1/N from one end of the string has been obtained. However, in the case when vibration suppressors are installed at 1/N from both ends of the string, no exact solution of the free vibration has yet been obtained. In this paper, an exact solution of the free vibration of this case is presented. Further, to verify the validity of this exact solution, a finite difference analysis of the string vibration with vibration suppressors is performed. The calculated results obtained from the finite difference analysis are in good agreement with those of the exact solution.

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A serious earthquake was occured in Japan on March 11, 2011 and some escalators fell off to downstair. A story drift make an installed length of a escalator fluctuate. Because of the forced displacement, the escalator-truss may catch the fatal damage. Therefore we carried out strength analysis (elasto-plastic analysis) of the escalator-truss. An Upper support angle is complete constraint condition, and lower support angle is taken forced desplacement. The maximum displacement is 200mm. Because the escalator-truss has horizontal reaction force when it is had forced displacement, we judged the frame to be able to become independent. A original-sized model displacement examination was compared with this calculation effect, we got similar force-displacement curve. We established strength evaluation means of the escalator-truss for the seismic design.

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In The Great East Japan Earthquake in 2011, fall accidents of escalator have occurred. In commerical building of the steel-frame, four escalators have fallen. These escalators were connected on the 3rd floor from the 2nd floor. In general, escalator set into building with either bottom or upper non-fixed style. In non-fixed side, escalator is supported by the L-form board and hanging to the beam of building. Non-fixed side absorbs layer deformation. However, it is thought that escalator came off by layer deformation with more than expected. After fall accident, the new earthquake resistant standard of the escalator was defined.by the new standard, escalator is less likely to fall. On the other hand, escalator receives compression force by a collision. It is necessary to clarify the seismic behavior of the escalator. From the above-mentioned background, the purpose of this study is to develop the analytical model of the escalator for seismic response analysis. In this paper, the development of analytical model takes the impact with beam of building. In addition, analytical model considers elasto-plastic property of the escalator truss. Seismic response an analysis of escalator installed in low-rise building. As a result, escalator receives compression force and residual displacement. Residual displacement becomes short of the overlap allowanve. Therefore, there is a possibility that escalator come off by an earthquake of a repeat.

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All buttons insalled in an elevator car should be easily operated by any passenger. Usually the installation height of the buttons affects the ease of operation. In this study, we have quantified the relationship among ease of operation and human height and standing position when passengers operate the buttons in an elevator. And we have created a relational expression for measuring ease of operating buttons by human height.

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An escalator handrail is driven along guide frames by a handrail driving device. Frictional force between a handrail and guide frames becomes running resistance that is drive force needed for handrail. Large frictional force to a handrail occurs at curved frames. About curved frames, traction characteristics were tested to estimate the forces at an entrance and an exit of the frames. It was clarified that those forces are expressed by the following equation. To = Tie^<μθ>+C (Ti: force at an entrance, To: force at an exit, μ: friction coefficient, θ: winding angle, C: offset value). Using the relation, new method to analyze drive force of an escalator handrail was proposed.

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Traction elevators are suspended by multiple ropes. Uneven sheave wears affect the rope tension during elevator operation. If the tension condition reaches o the traction capacity, a rope slip occurs. As the rope slip also affects the rope tension, a tension calculation with rope slip is necessary to evaluate the relation between the groove wear and the rope tension. In this paper, a tension evaluation model is derived by including the rope slip behavior and then the influenc of the rope tension due to the groove wear is evaluated numerically.

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