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Crane Spare Parts-Travel limit Switch

The travel limit switch is the electric appliance that the crane controls the motor according to the operation. According to different purposes, the Crane Spare Parts- travel limiter can be divided into two types: terminal switch (limit switch) and switch (protection switch). The end point switch is used to limit the operation of the mechanism in a certain range and is installed at the end of the travel of the operating mechanism. The switch is used to protect people. For example, the switch from the cab to the hatch of the upper main beam platform is called hatch switch, also known as door interlock.

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Although the internal wiring and external dimensions are different, the basic principle and structure of the end switch or switch of the travel limiter of various crane accessories on the crane are the same. They all have a sealed iron shell, and there are several normally closed contacts inside. These contacts are connected with the movable connecting rod outside the iron shell. As long as the connecting rod is impacted by the stop and moves, the normally closed contacts inside will be opened, so that the coil of the power contactor will be cut off and the power supply will be cut off to play a protective role.


The operation limit limiter of the crane is composed of travel limit switch and ruler. Generally, it needs to be installed on site. Pay attention to the position of ruler and limit switch during installation. For the crane of electric double beam crane, each crane is equipped with two travel limit switches and two rulers. The limit switches are installed at both ends of one end of the beam, and the rulers are respectively installed at both ends of the corresponding track. When there is a crane on the track and another crane is added, the new ruler and limit switch shall be staggered with each other during installation to ensure the reliability of limit.

The installation of limit switch and ruler for trolley travel limit depends on the specific situation. Generally, the upper ruler is installed on the trolley frame, and the limit switch of crane mechanical parts is installed on the bridge. When installing the travel limit, the requirements of specific braking distance shall be considered, and a distance of not less than 200 mm shall be left between the buffer and the crane or trolley until the stop of the crane or trolley after the travel limit takes effect.

Crane Spare Parts Of Dejun Hoist and Crane

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