Elevator door
Elevator doors are generally divided into elevator car doors (car doors) and shaft doors (shaft doors). Since they perform basic safety functions, the design, manufacture, installation and testing are subject to strict standards and regulations.
Nevertheless, there are numerous designs, variants and versions to meet the different requirements.
Types
sliding door
The power-operated sliding door is the most common. Where the shaft is big enough to move the door leaves to the side, they are used. There are left, central and right opening. If the doorway is very wide and the shaft is quite narrow, multi-part, so-called telescopic doors are used. Their disadvantage, however, is the greater installation depth. Sliding doors are now almost without exception power operated, i. that is, an electric motor is used for opening and closing. This is part of the car door drive. The movement of the car door is transferred 1: 1 to the shaft door (with shaft sliding doors) via a so-called dragging bar on the car door (this is why the automatic opening of shaft doors shown in some films without a car behind them is simply impossible.). Hinged doors are used where the use of sliding doors no longer makes sense.
Hinged door
Hinged doors (also known as revolving doors) are the oldest types of doors in general and lifts in particular. Revolving doors are not to be confused with revolving doors . However, they have been used exclusively as shaft doors (since the invention of the folding car doors). These are used either because of a lack of space in the shaft or for cost reasons. Especially in the case of old elevators without a car door (and without a door drive) there was no alternative. Hinged doors can almost always be opened manually, but they often close themselves using door closers or springs.
Folding door
This design is mainly used for car doors when the space for sliding doors is too tight. Due to their design, folding doors are only used up to a passage width of approx. 800 mm. This is often the case with passenger lifts that have been retrofitted in stairwells. They are very seldom used as shaft doors because the maintenance effort and the price are quite high due to the complex mechanics.
Lifting door
This type of door is only approved for freight elevators. With very wide doorways, where the above-mentioned types cannot be used, lifting doors are another option, both on the shaft and on the cabin side. As the name suggests, the door is opened by a lifting movement. Multipart telescopic lifting doors are used on the cabin, and one-piece doors can also be used as shaft doors. These then often have their own drive.
Slat lift / sliding door
This type of door should be mentioned for the sake of completeness, it is mainly used when retrofitting existing (freight) elevators without a car door. The functional principle is similar to a blind, due to the low price and the solid construction it is installed more and more frequently.
safety
To avoid accidents, all doors and door functions are subject to strict safety requirements. The EN 81 z. B. specifies in detail the minimum loads that doors have to withstand, the maximum forces that can occur when the doors are closed, the size of gaps and depressions is regulated, as is the electrical integration of the shaft and car doors into the elevator control. The most important safety element in all elevator doors is the door safety circuit. There are electrical contacts connected in series on all doors of an elevator , which forcibly and immediately interrupt the safety circuit and thus the power supply to the motor contactors if a door is not completely closed and locked. This ensures in a very simple and easily verifiable form that the elevator cannot travel when a door is open. Opening a door while driving also leads to the immediate abortion. Exceptions to this are elevators with what is known as readjustment, which is used to compensate for differences in level between the car floor and the storey floor, which can arise in particular when loading or unloading hydraulic elevators. A safety circuit is required for this, which monitors with two independent switches that the elevator can only move in an area of approx. 150 mm above and below the level with the slow travel speed. If an elevator system extends over two fire compartments, the elevator door must close by itself.
See also
Individual evidence
- ↑ Dieter Unger: Elevators and Escalators: A User Manual . Springer-Verlag, 2015, ISBN 978-3-662-46502-8 , pp. 106 ff . ( Preview in Google Book Search).