Evolution and status of elevator technology in the 1930s, AC induction motors because of its low price, ease of manufacture and maintenance is widely used in the elevator. By changing the number of pole pairs of the motor way to achieve the two-speed control requirements, the elevator controller, so drag simplify system architecture, and reliability are increased. Currently the majority of our elevators are used in this AC two variable-speed drive control. DC drag lift early in development to pay a single, after the two-speed drag the 1930s with the development of high-rise buildings, the elevator company, people on the elevator rated speed increasing demand, resulting in a DC-DC converter control motor drive of high-speed elevators. The system from the initial open loop, there is level, there are contacts to today's closed-loop control, stepless, non-contact control system. This is another elevator control technology progress. With the development of electronic technology, from the late 1960s to the early 1970s, he began to develop the application of AC variable speed AC motor drag it from the AC voltage speed to further the development VVVF system. With its outstanding energy savings within a certain range (≤4m / s) completely replace the DC drive system. It is currently developing technology that is considered a leap forward in technology drag lift. The rapid development of microelectronics technology allows for an elevator control microcomputer, Youyang elevator, is a comprehensive alternative to the contact-relay control mode. So that the elevator drive control, automatic scheduling control signal operation and to the technical characteristics of a new high MRL MRL is not simply get rid of the elevator machine room, but the concept of change and progress on the elevator. MRL applications, elevator decoration, building saves space, reduces the cost of construction to bring greater flexibility to the design of the building, more importantly, along with the application of new technologies, new member the elevator's performance can be further improved, more energy, more environmentally friendly, represent an important development direction of the elevator industry. Here, according to the current domestic and international developments MRL and I own many years of experience elevator inspection work on the part of the machine room less elevator technology initial elaboration. Youyang elevator, Gordon metal products, lift switch provided by the Chongqing Municipal Gordon Metal Products Co., Ltd.. Youyang elevator, Gordon metal products, Chongqing lift switch is Gordon Metal Products Co., Ltd. (www.cqgaodun.com) this year introduced a new upgrade, the above picture is for reference only, please call the telephone or pictures on this page obtain the latest information, contact: Deng Jianwei.