1. Field of the Invention
The invention relates to an arrangement for synchronizing the angle of rotation of the slats (also known as louvers) of a plurality of sun or window blinds which are simultaneously driven by electric motors, with which the turning or tilting of the salts is effected by means of a shaft arranged in a headrail and driven by an electric motor.
2. Description of the Prior Art
In very large buildings, a large number of sun or window blinds may be required, these blinds being provided with electric motor drives which are designed and constructed in such a way that the opening and the closing of the blinds, as well as the tilting and/or swivelling of the slats, is carried out either by the same motor or by separate motors. Such large window blind systems commonly have a central control by which, from a central point such as the building superintendent's station, all window blinds or the window blinds of one facade can be adjusted or readjusted simultaneously either manually or by means of an electric control device.
The central control must be capable of controlling the shielding effect of all sun or window blinds simultaneously and to the same extent, so that the slats of all blinds assume the same angular position in relation to the corresponding window planes. Formerly, however, this has not been possible, so that owing to the unavoidable slight differences in the blinds themselves, in the driving motors, slat-driving shafts, and bearings, etc., the angular positions of the individual blinds will usually differ from one another despite equal control stimulus. This not only causes a poor aesthetic total impression, but also has technical disadvantages, because the blinds do not produce the desired overall shielding effect.