| 摘要 |
1,210,310. Endless-band moving displays; sign supports. W. N. MILLER JR. 17 Sept., 1968 [18 Sept., 1967], No. 44047/68. Heading G5C. An endless indicia-bearing band 76 entrained about vertical drums 31, 66 is provided with detector means 140 adjacent the upper and lower edges of each drum which, if the band begins to slip off the drums, are engaged by the band and initiate a mechanism for tilting a drum (so restoring the band to its correct disposition), and subsequently restore the drum to its vertical orientation. Drum tilting.-As described, drums 31, 66 are mounted in yoke bearings Y, 61 respectively. As illustrated in Fig. 4a, tilting of a drum is achieved by a motor M rotating a screwthreaded shaft 46, causing movement of a screwfollower 47 and hence pivoting of yoke Y about a bolt 26. Tilting is controlled by microswitches 124 (Fig. 11), which energize a motor M and are actuated by detector rollers 140 which are displaced by tabs 76a, 76b if disalignment occurs. Extreme disalignment causes displacement of upper or lower safety switches 120 or 121 which cut off the band drive motor 60. Band tensioning.-The band is engaged by a friction sleeve G mounted on the drums, and is kept tense because idler drum 66 has its bearing yoke 61 secured to guide members 89 urged to slide to the right (in Fig. 3) by a spring 105, see also Fig. 9 (not shown). Alternatively, drum 66 may be replaced by three parallel rollers (141-143), two of them being tensioning jockey rollers mounted on spring-biased bell. crank levers (Fig. 15, not shown). Mounting.-Each of the runs of the band is viewed through a window in the framework, front-illuminated by tubes (L), Figs. 1, 2 (not shown). The framework comprises channelsection irons (C) clamped back-to-back about uprights (I) which support the sign, Fig. 13 (not shown). |
