Projection screens, e.g. of the type described in the aforementioned copending application, are generally provided with telescopingly extendable posts, carrying the projection screen in a tube which can be swung from a position in which the tube lies parallel to the post (for transportation or storage) into a position in which the tube extends transversely and horizontally so that the web of the screen can be withdrawn from the tube and fully extended.
The post is also generally equipped with a stand at its lower end having a plurality of spreadable legs which, in their outwardly spread position, can provide a purchase upon the ground or on a floor at a plurality of spaced apart locations to afford stability to the screen. It is also customary to construct the stand so that the legs can be contracted toward the post, i.e. to make the stand collapsible and thereby facilitate storage or transportation of the stand.
Earlier devices for this purpose included articulated arms and like complicated mechanisms which interfered with esthetics of the device and were prone to failure or were difficult to operate.
USPTO Backgrounds
USPTO Backgrounds