Height-adjustable support system for false floor in building has screw with chain drive from hexagonal shaft, installed where four corners of square floor plates meet

摘要

A flat plate (2) at the top end of the screw (8) has four upstanding pins (21) in a square array engaging in sockets in the corners of floor plates (22). The sockets in the plates are arranged in a regular square array around large holes, which are set in a regular 16x16 array. The screw has a male thread (12) engaging with a female thread (11) in a nut (7) welded to a sprocket (13). The sprocket may be held in a socket (9) on a ground plate (2) and may be secured against turning by pins (10). A chain (14) runs round the sprocket to a sprocket (15) on a winding shaft (5) with a hexagonal upward projection (20). This shaft is positioned under one of the holes in a floor plate so that it can be turned by a socket spanner extending down through the hole.