By use of VVVF technology to directly control elevator door operation simplified the mechanical structure of elevator door device with low noise in door closing and leveling in exact position.

采用VVVF技术对电梯开门机直接拖动，使电梯门机装置机械结构简化，关闭时噪声低，且可靠到位。

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Protection device: rapid rolling door is arranged at the bottom of the photoelectric device, touch the obstacles in the process of closing down, stop immediately rebound.

保护装置：快速卷门门柱底部装有光电装置，在关闭的过程中触及障碍物，立即停止下降反弹回升。

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The utility model relates to a slide block-connecting rod type door cover opening and closing device, which is suitable for being used in the fields of vessels, vehicles, hydraulic engineering, etc.

本实用新型涉及一种适于在船舰、车辆、水利工程等领域使用并采用动力缸驱动的滑块-连杆式门盖启闭装置。

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