Folding door
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A folding door is a door made up of several parts that fold up when opened. Construction variants are accordion door and folding sliding door .
Construction principle
A folding door consists of individual door leaves that are attached to one another at the sides with hinges , joints or hinge straps, and thus form the door as movable elements.
As with all sliding doors , two construction principles are possible:
- Hanging: The running machine is running in a located above the door track rail , on the ground, a guide rail is possible
- upright: The treadmill moves on a guide rail on the floor, an upper guide is generally mandatory, can be omitted in exceptional cases ( free-standing folding door )
Designs
According to EN 1527: 1998 Hardware for sliding doors and folding a folding door signs on paragraph 8 door type :
- Class 2 = folding door (2-leaf)
- Class 3 = multi-leaf folding door
Folding doors can be divided into three groups:
- Folding door in the true sense of the word: It consists of entire leaves and only folds to one side. The guide rollers are located in every second joint "at an angle". Due to their one-sided load when deflecting, a top and bottom guide is mandatory.
- Harmonica door: The attachment is mounted in the middle of each wing width, the wings fold in half inwards and outwards. The weight acts centrally and it is only a running device, but no guidance is required. The disadvantage is that a tight seal is not possible above or below, and this construction is only suitable for inside.
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Folding sliding door : These are doors that open “around the corner”. The wings can also run in curved guide rails and do not open. The space requirement is minimal.
- Folding sliding doors can fold both horizontally and vertically, and then usually run upwards and along the ceiling
Opening and closing can be done manually or via actuators ( electric , hydraulic or pneumatic ). Special sets of folding door fittings are used for locking and unlocking , which also allow heat and windproof construction.
One type of construction that is frequently used in rail vehicles is known as a folding pivot door .
Areas of application
- Folding doors are particularly suitable for spatially cramped locations in which a full sash cannot open, is annoying or endangered. The wing width can be chosen to be very small. Even with normal sash dimensions between 700 and 900 mm, accordion doors only slightly protrude from the stick.
- Folding doors allow large passage widths. Large areas can be covered with a number of fields. Folding doors are therefore suitable for verandas and entrances to winter gardens , or as room dividers for conference rooms and halls in the hotel, restaurant and event industry.
- Folding doors have no explicit list . This is why they are used in public transport ( trams , trolleybuses , omnibuses , silver coins) - where the door-operating driver usually has no direct view of the door - because the risk of trapping a passenger is comparatively low.
- All three advantages set them apart, especially for garage doors or lift shafts . With suitable rolling and guiding devices, doors of huge dimensions are also possible, for example for construction halls in aircraft and shipbuilding or for hangars .
The advantage of the folding door compared to a sliding door is that the sliding door requires at least a full sheet width of lateral space, while the folding door is optimally reduced to a dimension of sheet thickness × number of sheets.
Folding doors of light construction and good roller bearings open with little effort. The relatively slow opening process is disadvantageous. Therefore, folding doors of any type are not permitted for escape routes . A fire-resistant design is possible, however.
In furniture construction, they are particularly found in secretaries , chests of drawers and other fancy furniture . They are constructed using traditional craftsmanship, partly with a piano strap, but partly also from narrow strips that are stretched onto a fabric. This makes folding sliding doors possible with the smallest of radii.
history
Folding doors were already known to the Romans , as excavations in Pompeii ( Italy ) have shown.
Norms
Construction in general:
- EN 1527: 1998-12 Locks and building hardware - Hardware for sliding and folding doors - Requirements and test methods
- ÖNORM B 3852 2006-05-01 Fire barriers - lifting, lifting link, tilting, rolling, sliding and folding doors and gates - requirements, testing, labeling
- As well as the general standards regarding doors , fire resistance , automatic door systems
Special applications:
- DIN 18090: 1997-01 Elevators - Lift shaft revolving and folding doors for lift shafts with walls of fire resistance class F 90
Vehicle construction:
- DIN 27203: 2004-02 State of the railway vehicles - passenger compartment . Part 2: entrance doors ; Part 6: Front wall doors / transition doors ; Part 7: loading doors
literature
- See literature of the article Door