Tokyo 2020 Olympic and Paralympic Games will be held in 2020 in Japan. Toward the big international event, policies, laws and guidelines regarding accessibility of public transport have been revised under the initiative of Government. This paper focused on the topic of outline of the revision of public transport accessibility guidelines and its challenges and prospects.

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Most elevators applied to tall buildings include compensating ropes to satisfy the balanced rope tension between the car and the counter weight. The compensating ropes receive tension by the compensating sheave, which is installed at the bottom space of the elevator shaft. It is important to evaluate the vertical displacement of the compensating sheave, because the displacement is one of the key factor to determine the pit depth of the elevator shaft. This paper shows an elevator dynamic model that calculates the compensating sheave motion during a brake activation of the traction machine. Firstly, an elevator system model is proposed to evaluate the vertical motion of each component. The derived simulation model indicates that the vertical static displacement of the compensating sheave depends on the car position and the car loading condition. Secondary, the vertical vibration induced by the brake of the traction machine is evaluated numerically. It is concluded that the maximum vibration occurs when the vertical vibration by the car stop timing synchronizes the phase of the vibration by the brake activation. The maximum vibration is also evaluated by a mathematical formulation and it shows that the vertical vibration is proportional to the building height.

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Notification No. 1046 of the Ministry of Land, Infrastructure, Transport and Tourism was issued in October 2013. For the coseismic interlaminar displacement of the building, it is necessary to secure sufficient dimensions in the hanging dimension of the escalator support and the gap between the support and the building beam, but it is the issue to increase support. To efficiently calculate optimum dimensions that satisfy the condition of minimizing the support and the coseismic securing strength, it was reducing the evaluation time by 56% compared with the conventional process by applying the experimental design and replacing the elastic plastic analysis of the experimental design with linear analysis.

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Wire rope has high tensile strength and rich flexibility because of its complex structure. Therefore, wire rope is now used in various products such as crane and elevator. However, wire rope also has a problem that it is difficult to inspect inside of the rope and several accidents caused by the rope rupture have been occurred. Although fatigue test has been done to grasp the life of the wire rope, it takes a high cost and we cannot know the inside state such as tensile stress during the test. Finite element analysis is also done, but operation load would be very heavy if we use the full FE model. The purpose of this investigation is to grasp the inside state of the wire rope, by the finite element analysis using a simplified FE model, and reveal the fracture tendency. In order to make the simplified model, we perform the radial direction compression test of a strand and wire rope and measure the material characteristics.

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We provide escalator maintenance services to keep the condition of escalators optimal. The handrails that passengers grip when they get on/off the escalators are important parts for their safety. However, in rare cases, aged deterioration of reinforcing steel cords in the handrails make them break and come out of the handrails, and passengers might get injured. But we cannot inspect the codes directly, because they are embedded in the handrails. So we have developed a new diagnostic device to inspect the codes indirectly using the magnetic leakage flux test method.

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When thinking about elevator safety, specifically elevator inspection and maintenance operation, the monitoring and management of the wire rope condition - due to daily usage – is critical. Currently, elevator maintenance engineers develop a wire rope replacement plan by capturing the degraded condition of the wire rope based on results of visual checks and data collected (via use of a caliper) from measuring the rope diameter. However, market demand of high-speed elevators is increasing based on the growth of high rise buildings. In fact, just this year, a 600m (approx.) hoistway was measured and recorded – this is the highest to date. As a result of buildings climbing ever higher, extended elevator maintenance time has also increased and become a key challenge to overcome. Work hours have grown proportionally longer as hoistway heights rise. Unfortunately, longer hours can often lead to increased human fatigue and error during rope diameter measurement and maintenance. A more efficient and accurate process is needed. The development and implementation of a rope inspection device, using image processing, can mitigate existing challenges. This inspection device utilizes a high resolution line sensor camera with a high level image processor to more efficiently provide the rope diameter measurement data of the high speed moving ropes. This paper was created to report the general system configuration of the developed device, the image processing method and the results of verification tests.

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We focused on the step-wise pattern of air pressure adjustment patterns applied to an air-pressure adjustment device for alleviation of ear stuffing that passengers feel in a cab of an elevator. Each step of the step-wise pattern consists of three elements which are the amount of air pressure change, the rate of air pressure change and the time with no change in air pressure. In this study, we have quantified the relationship between intensity level of ear stuffing and each of the three elements. And we have created relational expressions which can estimate the intensity level of ear stuffing from the three elements. Accordingly we can decide the most effectual air-pressure adjustment pattern for alleviation of ear stuffing with these relational expressions.

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Vibration suppressors are used to change the natural frequency of an elevator rope and prevent resonance. The displacement of the parts of the elevator rope at both the ends is small compared to that of the center part of the rope; therefore, it is not necessary to position the vibration suppressors in the parts on either ends. In this paper, theoretical solution to the free vibration of the rope is obtained, in the case where vibration suppressors are located except for both ends part of the rope and the pulled position is (q-2(i-1))L/2N from both ends of the rope. The natural frequency is 2N/(N+1) times of the original natural frequency. And another theoretical solution is also obtained, in the case where the pulled position is pL/2N from both ends of the rope. The natural frequency is 2N/(N+p) times of the original natural frequency. Where L is rope length, p, q, N (=2p+q) and i are integer. Further, finite difference analysis of the rope vibration with vibration suppressors is also performed to obtain the frequency response curves. Resonance frequencies obtained by the finite difference analyses are in good agreement with the natural frequencies for the free vibration.

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An elevator for a high-rise building ought to perform emergency operation when the elevator rope is oscillated by the sway of the building caused by wind force or long – period ground motion. In recent years, techniques for directly measuring rope amplitude in real time have been utilized. Thereby, it has become possible to perform apposite emergency operation based on the rope sway condition. On the other hand, the rope sway changes continuously every moment during the travel of elevator. Therefore, it is very important to grasp the changing tendency of rope sway for the efficient judgment of emergency operation. In this research, we constructed a simulation model which quantitatively simulates the rope sway motion during a travel of an elevator.

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As high-rise buildings increased, vibration to the elevator car and rope oscillation synchronized with building swinging during strong wind became big problem. It might cause not only the deterioration of ride comfort but also machine trouble. Various studies have been conducted on rope oscillation. However, most simulation studies employed a rope only model, interaction of whole elevator system and influences on the car were not considered. In the previous study, traction machine, car and main rope were modeled in up-and-down direction by multibody dynamics and good agreement with experimental results and simulation ones were obtained. In this study, to grasp an exciting force to a car from main ropes when the building is oscillated, a new model including swinging motion was proposed.

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Elevators are essential for means of vertical transportation. In recent year, elevators to be installed in high-rise buildings are long stroke, thus the elevator ropes are longer. High-rise buildings have longer natural period than conventional buildings. As elevator ropes become longer, the natural period of the elevator ropes become longer as well, and get closer to the natural period of the building. Consequently, the elevator ropes are hooked to the equipment in hoistway when the elevator ropes vibrate by an external force, such as a strong wind and earthquake. Secondary damage such as containment of passengers and elevator service stop may occur. It has become a problem. For example, The 2011 off the Pacific coast of Tohoku Earthquake, 2215 cases such as catch and damage of elevator ropes have been reported. However, operations of elevators after earthquakes are required. Therefore, in this research, we aim to design elevator that can be operated even after the earthquakes. Conventional research has confirmed that dividing lift stroke install multiple elevators is effective for reducing the response of the rope. In this method, the lift stroke is equally divided. However, the displacement of the upper elevator becomes larger. Therefore, in this report, we examined the effectiveness of the case of changing the division ratio of lift stroke. The analysis and probabilistic risk assessment, changing the division ratio confirmed that displacement and probability of catching rope of the upper elevator are reduced.

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