Abstract: A table includes a platform comprising a horizontal surface and an upright support beneath the horizontal surface, the support having a dimension of height. A first hinge hinges a leaf to the platform and a three link lock system interlinks the leaf and the platform so the leaf can be locked in a plurality of angular adjusted positions. The three link system includes a part of the leaf, a part of the support, and a shaft which is pivotally mounted to the leaf. The shaft is shiftable in the lock so as to vary the length of one of the links.

Abstract: There is disclosed an electric system for controlling the direction of rotation of two counter rotating motors operated from a source of A.C. line voltage, the system comprising a selecting circuit operated by a rectifier connected to the source and containing two junctions, a first of which is at a D.C. voltage V when the second is at zero voltage and vice versa. A reset switch operated mechanically by rotation of the motors puts the voltage V alternately at the first junction and the second junction. When the voltage V is at the first junction it produces a pulse in a first control path which controls the first of the motors and when it is on the second junction it puts a pulse on the second path for operating the second motor. Each control path comprises a latch circuit operated by the pulse, a time delay circuit and a motor control circuit including a power switch operable at the end of the time period to torque the respective motor.