A COLLAPSIBLE SPEED BUMP ASSEMBLY

摘要

A collapsible speed bum assembly (17) relies on inherent inertial delay being exceeded by a passing vehicle to release the speed bump so it can collapse, if the vehicle is faster than the delay the speed bump remains erect. The assembly comprises a housing (18), a collapsible speed bump (19) hinged to the housing at an upstream end (20) at hinge (21) and in Figure 2 is shown in a raised position. The speed bump (19) comprises an upstream plate (22) and a downstream plate (23) hinged together at hinge (24). The plates (22) and (23) move in a downstream direction as a vehicle wheel strikes plate (22). The housing (18) has a seat section (25) to accommodate the plates, the seat section extends from the hinge (21) downstream to the inner edge (26) of the cross frame member (27) so it is shaped to match the flattened plates (22) and (23) which fit into it. The plate (23) has a leading edge (28) that moves downstream as a vehicle wheel strikes plate (22) but blocking the leading edge are three projections (29, 30) and (31) which project through corresponding holes (32, 33 )and (34) in the housing (18) and serve to arrest this movement when the leading edge strikes them. Only by retraction of the projections (29, 30) and (31) will the speed bump collapse.