Mitsubishi Electric Corporation (Mitsubishi Denki kabushikigaisha, also abbreviated as MELCO), established on 15 January 1921, is a Japanese multinational electronics and electrical equipment manufacturing company headquartered in Tokyo, Japan. It is one of the core companies of Mitsubishi. The products from MELCO include elevators and escalators, high-end home appliances, air conditioning, factory automation systems, train systems, electric motors, pumps, semiconductors, digital signage, and satellites.
Most curving escalators once proposed around the world were based on methods for movement in a concentric circle. But none ever made it to market. Even though the speed of horizontal movement when creating a semi-circle is regular, making it possible to move concentrically, the structural problem is that movement in the horizontal direction slows to the extent that there is vertical movement in the inclined section. Mitsubishi Electric overcame this issue by developing the “centralized motion method,” in which the central point moves in stages based on the angle of incline.
Escalators drawing arcs are unique in appearance. The rotational moment is complex in form, with the longitudinal movement closely intertwined. To accomplish this, although the concept had long existed around the world, it had not been successfully achieved. Then, in 1985, Mitsubishi Electric successfully developed what is now called the “SPIRAL ESCALATOR.” Today, Mitsubishi Electric remains the only company to manufacture the SPIRAL ESCALATOR.
At first glance, these escalators appear to have curvatures without any special features. But the arcing structures achieved use elaborate, sophisticated technologies only capable of being realized by applying the design, manufacturing, and installation skills of expert engineers.
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