Analysis and prevention of common elevator failures in elevators - Solutions - Huaqiang Electronic Network

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Analysis and prevention of common elevator stop ladder failure date: December 5, 2011 With the advancement of technology, the level of design, manufacture, installation, inspection, maintenance, maintenance and use of elevator technology and management is continuously improved, and its operation The reliability has increased significantly. However, in the maintenance and repair, there are still some typical parking ladder failures, in which the elevator can not run the most because of the safety loop. First, the phase failure caused the stop ladder When the three-phase power supply phase failure, the phase sequence relay action cuts off the safety circuit, so that the elevator stops running. This kind of fault is more in the elevator logic control elevator, because it is an old-fashioned elevator, the power switch is mostly guillotine type, the power supply passes the limit switch, and then sent to the elevator control cabinet, the two switches through which the power supply flows, a total of six fuses. The elevator runs and starts, and the current is very large. After a period of operation, if the maintenance personnel do not check in time, the connection between the fuse and the screw is extremely easy to blow, the elevator is out of phase, causing the elevator to stop, and the passenger is shut down, and the accident occurs.
The main preventive measures: a. Maintenance personnel should always inspect and check, find suspicious places, timely repair, hot and sparking should be replaced immediately. b. It is recommended that the user replace the knife switch with a relatively large capacity air switch. c. The elevators designed now have no power limit switch. The author believes that the safety circuit can be slightly modified, that is, the upper and lower limit electrical switches are installed in series in the safety circuit to remove the original limit switch. After bc processing, this fault can be completely eliminated. Second, the rise of the rope wheel switch causes the stop ladder to be like a traction rope, and the speed limiter rope will also elongate during use. Due to the effect of the bottom pit rising rope weight, the rising rope wheel switch is offset until the switch is opened.
This type of failure, for newly installed elevators, maintenance personnel must check once a month, after one year of operation, check once every three months, so that it can prevent problems before they happen. The author has encountered several phenomena that caused the three switches to move at the same time because the mouse fell into the pit and broke into the rope wheel. Due to the lack of strict sealing of the hall door and the wall hole in the hoistway, some rats will fall to the sluice when they break into the hoistway. Some of them will fall into the pit and try to escape into the sling and get stuck in it. The elevator runs down. This leads to the safety clamp switch action, and some speed limiter switches are also linked together. There is also a mouse in the machine room into the speed limiter, causing the above failure. The basic solution to such failures is to prevent rats. Anti-rat measures such as spraying appropriate mouse drugs in the corner of the machine room and pit can be taken to reduce the occurrence of malfunctions. Third, the door interlocking failure caused by the failure of the elevator design requirements: each floor of the elevator door and the car door must be closed after the elevator can start running (fast), if any floor hall door or car door does not close the elevator Can't run.
Due to the ash accumulation of the door lock contacts, the contact is poor, resulting in fire, resulting in the phenomenon of stopping the ladder, when the time is good or bad, but the fault is not known.
Since the engagement depth of the lock hook and the door lock stopper is too small, the door lock contact is not completely pressed, resulting in poor contact. The national standard meshing depth is greater than 7mm. It is also seen from this point that as long as it is greater than 7mm, the contact pressure is increased to avoid contact failure.
Due to the excessive clearance between the lock hook and the stop, if the passenger knocks the door outside the hall door, the door rope break switch will be disconnected and the elevator will suddenly stop during operation. The passengers let go and the elevator returned to normal.
Such faults require the maintenance personnel to check whether the door lock contacts, the gap, the door wire rope are extended, whether the door connecting rod is loose, whether the door lock block lock hook is deformed or damaged. Find problems, eliminate them in time, and reduce unnecessary stoppages. In reality, the situation in which the elevator stops running and the person is locked in the car sometimes occurs. Because the elevator is closed, the people in the car are panicked, kicked and chaotic, and the elevator is damaged, and personal injuries are caused. Some people will not fall into the hoistway because they will not save themselves. Some rescuers will save themselves and cause themselves to fall into the hoistway. Therefore, reducing the problem of stopping the ladder is a very important issue for manufacturers, installation units, maintenance personnel and passengers.