GB699699A - Improvements in or relating to combination draughtsman's desk's - Google Patents

Abstract

699,699. Draughtsman's desks. FRANKLIN, S. J. May 26, 1952 [Feb. 10, 1951, No. 3285/51. Class 52(iii) A combination desk and drawing board of adjustable height has the working surface 25 hinged at 24 adjacent the front edge to a horizontal frame 23 secured to upper extensions 22a of a pair of spaced levers 22, each forming one link of two parallel link systems 15, 19, 22, 20 associated with a transverse shaft 18 revolubly mounted between the pedestals 10, 11 of the desk. The pedestal 10 has drawers and a top 10a with which the surface 25 is flush in the desk-forming position. Secured to the pedestals 10, 11 are rails 15 with upper and lower bearing pins 17, 16, the pins 17 supporting the transverse shaft 18 to which the links 19 are rigidly secured. Parallel links 20 connect the lower ends of the links 22 with the lower pins 16 and arms 51 on the shaft are connected by counterbalancing springs 52 to the ends 15a of the fixed rails 15. A stop 26 limits the upward movement of the desk, and the desk is held in any position of vertical adjustment by jaws 28a of a toggle linkage 28, 32 extending along the shaft 18 and acted on by a spring 37 so that the jaws normally grip stays 31 pivoted at 23b to the frame 23. By turning a lever 27 in the direction of the arrow B, the jaws are released to.allow vertical adjustment. At any position the inclination of the desk can be adjusted by pulling a rod 48 which turns a lever 41 at each side to bring an ear 42 into a position at right angles to a stay 46 passing through a hole in the ear and pivoted to the desk at 47, releasing the desk for angular movement by a handle 25a at the rear. The lever 41 is normally spring-pressed into the position shown, in which the ears 42 grip the stays 46