Roller blind (sun protection)
The roller blind or rouleau (French: "roll") is a form of privacy or light protection on windows or glass doors, in which a mostly rectangular material is wound on a shaft . A modification of this is the pleated blind - here the fabric is folded when it is pulled up instead of rolled up.
Roller blinds are available in different degrees of transparency, colors, patterns, sizes and shapes. Even triangular or trapezoidal shapes are feasible to a certain extent. Opaque materials let light through, but prevent insights. Lightproof materials can be used, for example, to darken bedrooms or improvise darkrooms for chemical photography. In the case of passive air protection, on the other hand, light-tight roller blinds prevent light from penetrating a building and thus providing clues for bombing. By coating the textiles z. B. with Teflon or aluminum can also achieve insulation effects.
There are different types of blind controls:
- Side pull operation (also known as chain roller blind ): This is now the most common variant. On the right or left of the shaft there is an endless cord or ball chain that can be used to turn the shaft and thus pull the roller blind fabric up or down. The advantage of side pull operation is that it is low-maintenance, can be operated continuously up and down, has a long shelf life and is very easy to operate even with larger roller blinds.
- Central operation (also called spring or snap blind): The name "snap blind" arose from the fact that earlier blinds that were on tension simply "snapped" upwards when released. To operate the spring roller blind, the roller blind fabric is pulled down on a cord or cord bell or an operating handle. As a result, the spring located in the roller blind shaft is tensioned, which is provided with a centrifugal force-controlled stop mechanism that reacts to the rotational speed of the shaft. If you want the roller blind to stay down, you have to make sure that the spring locks. This can be done by carefully stopping the roller blind at the desired height. Accordingly, the spring can be released again with a jerky movement if you want to let the roller blind roll up again. This operating variant requires a little patience and practice in handling the stop mechanism.
- Electric drive : There is an electric motor in the roller blind that turns the shaft. This variant is particularly recommended for inaccessible roller blinds (e.g. at great heights). In addition, the radio motor should be mentioned, which can be operated either via a hand transmitter (remote control) or a wall transmitter.
- Snap : For skylights are often used blinds whose weight bar can be locked down in the right and left mount brackets. The spring mechanism of the roller blind is used as the basis for this system, which is kept under constant tension thanks to a technical modification and cannot lock.
