Abstract: A flexible door assembly includes an upper guide track comprising an elongate bar including at least two generally planar support surfaces. The upper guide track is mounted in the elevator cab, or outside the cab in the hoistway, above the door opening, defining a non-linear pathway. A plurality of door sections each having a door panel, and a carriage assembly including a carriage frame and at least two wheels each supported by, and in rolling contact with, one of the at least two support surfaces on the guide track, a hinge pin supported by the carriage, a door panel pivotally connected to the hinge pin, and wherein the carriage, the hinge pin, and the door panel pivot about the same vertical axis defined by the longitudinal axis of the hinge pin when a door assembly has moved through a bend in the upper guide track.

Abstract: An elevator door operator for positioning elevator doors along an arcuate pathway includes a linearly displaceable actuator and a pair of linkage arms, each pivotally connected to the other and connected to one end of the linearally displaceable actuator. The linkage arms are also each pivotally connected at their opposite ends to each of two support arms, each of which support arms are pivotally connected at one of their ends to each other and secured at their opposite ends, respectively to each of the door panels.

Abstract: An elevator door interlock includes a position indicator mounted at each landing, an elongate vane pivotally mounted in a fixed position with respect to the car door for movement between a first position, preferably several degrees rotated from perpendicular, and a second position, preferably generally perpendicular to the door surface, a swing latch including a latch arm secured at one end to the vane, preferably extending generally perpendicular to the vane, a contact plate secured to the end of the swing latch opposite the vane end, and a stop plate mounted in a fixed position with respect to the elevator car. The vane is preferably mounted on a spring-biased hinge, and is normally biased towards the first position such that the contact plate extends into the plane of the stop plate and contacts the stop plate to prevent further opening of the elevator door more than a limited distance when the door is opened unless the elevator car door is moved into a safe landing position within the hoistway.

Abstract: An elevator car door operator includes a drive motor, a drive pulley mounted for rotation by the drive motor, a continuous loop drive belt mounted on the drive pulley at one end of the belt and on an idler pulley at the other end of the belt, a drive bar connected to the drive belt and slidably mounted on a bar guide for translational movement across the elevator car door header. One or more doors are slidably mounted on guide tracks for movement between open and closed positions. One of the doors is either connected directly to the drive bar, or connected to a two-to-one relating cable mounted on the drive bar, so that the motion of the drive bar is transmitted to that door, thereby slidably positioning the door as the drive bar is slidably positioned by the belt along the length of the bar guide.

Abstract: An INVAR 36 material having long-term dimensional stability is produced by sintering a blend of powders of nickel and iron under pressure in an inert atmosphere to form an alloy containing less than 0.01 parts of carbon and less than 0.1 part aggregate and preferably 0.01 part individually of Mn, Si, P, S, and Al impurities. The sintered alloy is heat treated and slowly and uniformly cooled to form a material having a coefficient of thermal expansion of less than 1 ppm/.degree.C. and a temporal stability of less than 1 ppm/year.