[in Japanese]

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Escalators run by chain drive, and the chain, which is wound up as a polygon inscribed in the sprocket, causes speed pulsation due to its geometric motion on the sprocket. If the number of teeth on the sprocket is fewer, the speed pulsation will be large. It is obvious that the number of teeth decreases in the following two cases, one is the case when we make the diameter of the sprocket smaller to reduce the space, the others is the case when we make the chain link larger to reduce the cost. In these cases, the pulsation in the chain will be large and it will make a rider uncomfortable significantly. This paper explains a new drive mechanism to suppress the speed pulsation, which in the method adding fixed rail which can achieve optimal trajectory against the chain roller. The mechanical design of the new system is investigated by kinematics analysis, and experiment results with prototype shows its validity.

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We have developed a diagnostic algorithm for estimating the spring load and sliding resistance of elevator brake shoe drive mechanisms. Elevator brake drums are released by the attractive magnetic force of a solenoid coil. The spring load and the sliding resistance hinder the solenoid coil from releasing the elevator brake drums. These two factors affect the response delay of brakes. To calculate the sliding resistance, we need to know the biased magnetization of the core, however the biased magnetization is hard to measure. We estimated the sliding resistance using a coupled magnetic field and a mechanical model. The model consists of components for calculating the biased magnetization and lever deformation. We can also use the model to estimate the spring load. The proposed algorithm was tested using data from a machine in a site. The testing showed that the algorithm had the ability to estimate the spring load with 2% precision, and the sliding resistance with 5% precision.

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In order to investigate the influence factors on HIC (Head Injury Criterion) score of attenuation materials used for playground, impact tests were carried out in accordance with ASTM. Four kinds of the commercial attenuation materials were employed for the tests. The apparatus is composed of the missile made from aluminum alloy with a mass of 4.6 kg and a tri-axial accelerometer. The higher the missile was dropped, the more HIC score increased. From the time-frequency analysis, it was obvious that HIC score depended on the natural frequency of the vibration system in collision between the missile and the attenuation material. There was sufficient evidence to suggest that the use of a simple vibration system with a nonlinear spring is beneficial to assess HIC score.

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We have developed a high-accuracy calculation method for estimating number of shutdown elevators in moderate earthquakes. In this method, we introduced the seismic intensity-acceleration ratio as an index representing the frequency characteristics of earthquakes. The intensity-acceleration ratio is calculated by dividing the maximum acceleration response of the ground motion observed at a few points in the earthquake area by the seismic intensity of the corresponding area. This ratio is used to compensate the seismic intensity estimated by conventional method to reflect the frequency characteristics of earthquakes. The proposed method was verified using data from several earthquakes recently occurred. The results show that the average estimation error is greatly reduced from 85% to 20% in comparison with the conventional method.

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This paper presents a brand-new system for elevator group control. In past, passengers had to push buttons at halls and in elevators, so elevators had to stop at many floors in morning up-peak. The new system can collect passengers to the same floor, because their destinations are automatically registered in passing by security gates. The relationship destination floors and IDs are set to security system on ahead. In result, it reduces around trip times and traffic efficiency is improved. A result of demonstration experiment shows that the new system makes traffic handling capacity increased by 15%, compared to conventional UP/DOWN button system.

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In recent years, DCS(destination control system) has been introduced as a way to increase up-peak handling capacity. While DCS provides sufficient performance for up-peak traffic, the performance gain is not evident for different traffic patterns such as those during lunch time. In practice, however, various kinds of traffic patterns will come, and some kind of solution becomes necessary. In this paper, we propose elevator groups which have a large number of smaller cars with destination control system. We have analyzed our proposed system by using traffic calculations and simulations. Here we report on the performance results, which show that such systems have great advantages.

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This paper describes a problem of disk type governor and its suggestions for improvements. A disk type governor is widely used as a device that detects the over-velocity of the elevator. However, this type of governor has the acceleration dependence that operation is delayed by the influence of the acceleration of elevator. In this paper, we investigate the influence factors of the acceleration dependence of disk type governor by simulation model in order to improve the safety of elevator. Moreover we make a trial governor based on the result of the investigation, and confirm the improvement effect by the experiment.

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Elevator system has various safety devices for safe travel. However irregular actions of the safety devices cause the troubles or accidents. The governor is one of the safety devices and connected to the elevator car through governor rope. It detects the excessive velocity of the elevator car and then shuts off elevator system. In the case of the governor rope is shaken by the elevator car, the circumferential velocity of the governor may become high by resonance of longitudinal vibration of governor rope. This phenomen6n becomes more serious when the building becomes higher. In this study, modeling of governor and governor rope were proposed by multibody dynamics to investigate the governor characteristic. And the validity of the proposed modeling was confirmed by simulations and experiments.

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LED lightings compatible with straight tube fluorescent lamp begin to be marketed for a factory, an office building and a commercial institution. But LED light for circle fluorescent lamp is difficult to be marketed due to high cost by geometric limitation. Therefore, we developed LED lighting compatible with circle fluorescent lamp for elevators. For the structure that we could change it easily by removing a fluorescent lamp with appliance, we realized low cost. We devised a light-emitting surface and appliance shape not to lose an expanse of the light that was characteristic of a round shape fluorescent lamp. It is the product which can secure the illumination equal with fluorescent lamp.

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Many customers request the replacement of an installed hydraulic elevator with a rope traction-type elevator. However, since a conventional renewal type elevator requires a long work period and incurs high costs, the renewal market for hydraulic elevators is not expanding. We have developed a renewal product of its latest machine-room-less elevator that is environmentally friendly, saves energy, and provides a comfortable ride. And shortened work period and low cost have been achieved by using the existing hall parts, car, rail, etc. The renewal product eliminates hydraulic operating fluid. Further more it reduces power consumption, switching parts, etc. We show the techniques of the replacement of an installed hydraulic elevator with a rope traction-type elevator in this paper.

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