Abstract: To enable the ready transport and erection of radiant energy shielded enclosures at locations having various immovable obstructions, shielded joints of several different types each having shielded splices therein are provided for the connection in the enclosure of adjacent sheets occupying a common plane or two right angular planes. A compound joint at the intersection of three right angular planes occupied by sheets of the enclosure is also provided. The construction is applicable to future expansion of existing shielded enclosures without sacrifice of shielding performance at the interface of the addition with the existing portion.

Abstract: An operating and speed control mechanism for revolving doors features an improved gearing arrangement which makes possible a gear ratio of reduction between the drive motor shaft and door shaft far greater than any gear reduction heretofore attainable, even when using a greater number of gears in the allotted space. Additionally, the improved gear transmission renders the mechanism even more compact than the most favorable prior art arrangements in the interest of satisfying more stringent architectural requirements in the installation of revolving doors. Unexpected benefits provided by the improved and simplified gearing are increased braking efficiency and extra braking force from a small centrifugal brake assembly, and greater and more efficient lubricant circulation in the mechanism for the purposes of brake surface wetting and general lubrication and cooling of the mechanism.