| 摘要 |
A crossing arm assembly that includes either one or two hollow, tapered fishing rod bodies cantilevered at their butt ends to a beam-mounting portion of a combined pivot/bracket. A crosspiece connects the tips of the rods. The combined pivot/bracket pivotally attaches to a support at the front end of a bus to block pedestrian traffic from crossing immediately in front of the bus when the bus is stopped. The rods are tapered in mass and cross-sectional area from their butt ends to their tips. The taper concentrates rod mass closer to the support to reduce the tendency of cantilevered rods to sag under their own weight and/or to swing forward as the bus decelerates. The taper also increases rod flexibility to prevent plastic rod deformation and to reduce loads on the support when external forces are applied to the rods. A flap is pivotally attached to one of the rods to increase beam visibility without adding significant wind resistance. The combined pivot/bracket has a U-shaped body with a vertical beam integrally connecting upper and lower pivot arms. A rod-mounting boss extends integrally outward from the beam. Upper and lower receptacles in the rod-mounting boss receive the butt ends of the two rods.
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