摘要 |
<p>The door comprises at least one sliding leaf which is capable of engagement and disengagement transversely within the door-frame, two separate toothed racks being mounted on each leaf and each associated with a pinion supported by a guided carriage, the two pinions being coupled by means of a coordinating shaft. Operating means comprising a motor and a mechanism for driving the pinions are rigidly fixed to at least one of two crank-arms, each crank-arm being pivotally connected to a carriage and to the door-frame.</p> |