| 摘要 |
<p>The door has a guide rail (11) centrally over the door panel and counterweighted (6) lever arms (4) on the panel flank with the rail guided rollers being mounted on the panel and the weights (6) assisting panel manoeuvre during opening and closing. The rail (11) is the principal door guide. Either shoes or rollers are used, resp. sliding or rolling on the rail. The lever arms are attached (3) to the lower half of the panel, revolve about wall mounted axles (5) and act in conjunction with counterweights (6) or springs for equilibrium. The rail (11) can be of 'I' or any other suitable section. Side walls need not be rigorously parallel.</p> |
