| 摘要 |
<p>1,252,963. An up-and-over door. H. HORMANN [trading as HORMANN K.G.]. 13 Jan., 1969 [12 Jan., 1968; 8 July, 1968], No. 1981/69. Heading E2M. A tiltable door 2 mounted in a door frame 1 for swinging movement about its top edge, has mounted near its top edge rollers 4 which are connected to a motor 5 and slide in rails 3. On each side of the door there is a compensating arm 6, these arms are pivoted at 7 to the door near its lower edge 8 and pivoted at 9 to the door frame 10. The free ends of the arms carry the ends of tension springs 11, the other ends of which are connected to the door frame 13. The effective length of the lever arms of the compensating arms may be made variable by having (a) elongated slots for pivots 9, (b) a helical spring between each arm and its pivot 7 or (c) an intermediate lever and adjustable spring at pivot 7, so as to ensure that rollers 4 remain in driving engagement with rails 3.</p> |
