[0015] A further significant aspect and feature of the present invention is an array of automatic flexible airflow operated valves co-acting with arrayed orifices in a plenum bottom。 When air is flowing, each valve is positioned by airflow against the plenum bottom to seal the bottom of the plenum。 When air is not flowing, each valve relaxes and gravitationally repositions from intimate contact with the plenum bottom to break the seal with the bottom of the plenum。

[0016] Having thus described embodiments of the present invention and mentioned some significant aspects and fea- tures thereof, it is the principal object of the present inven- tion to provide a street sweeper having dust control from two or more cleaning heads with one air source, and which also provides for filter cleaning。

BRIEF DESCRIPTION  OF THE DRAWINGS

[0017] Other objects of the present invention and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein:

[0018] FIG。 1 illustrates a cutaway overview of the street sweeper having dust control from two or more cleaning heads with one air source, the present invention;

[0019]    FIG。 2 illustrates  a cutaway  side view  of  the  street

[0020] FIG。 3 illustrates an exploded view of the filter, certain components of the plenum, the filter shaker mecha- nism and other associated components which, in part, pro- vide for dust control from two or more cleaning heads with one air source for the street sweeper;

[0021] FIG。 4 illustrates an assembled view of the filter mechanism, certain components of the plenum, the filter shaker mechanism and other associated components which, in part, provide for dust control from two or more cleaning heads with one air source for the street sweeper;

[0022] FIG。 5 illustrates a cutaway view of the hopper, the filter mechanism, and the plenum along with other compo- nents associated with those parts, and also illustrates the multi-component  gutter  broom duct;

[0023] FIG。 6 illustrates a cutaway front view of the hopper revealing the filter mechanism, the plenum, and other components associated and utilized therewith during the sweeping  mode;

[0024] FIG。 7 illustrates a cutaway front view of the hopper revealing the filter mechanism, the plenum, and other components associated and utilized therewith during the filter mechanism cleaning mode during which the eccentric cam of the filter shaker mechanism is actuated;

[0025] FIG。 8 illustrates a view of the hopper and asso- ciated components for the street sweeper in the tipping position at the level of a truck chassis;

[0026] FIG。 9 illustrates a view of the hopper and asso- ciated components for the street sweeper in the tipping position above the level of a truck chassis; and,

[0027] FIG。 10 is a simplified schematic  of  airflow through the components providing dust control from two or more cleaning heads for the street  sweeper。

DETAILED DESCRIPTION OF THE PREFERRED   EMBODIMENTS

[0028] FIG。 1 illustrates a cutaway overview of the street sweeper 10, the present invention, having dust control from two or more cleaning heads with one air source。 Major components and other components complementary to the street sweeper are mounted to and secured to the frame or chassis 13 (FIG。 2) of a truck 12 or are mounted elsewhere at other locations about the invention。 Major components of the invention include a vacuum source, such as a fan 26, a fan shroud 27, a hopper 14, a plenum 34, an orificed plenum array 35, a plurality of one-piece flap valves 37a-37n (FIG。 3), a filter mechanism 30 including a filter 33 and other components which provides for support and function thereof, and a filter shaker mechanism 31 (FIG。 2), the majority of which connect associatively with other major members and components of the street sweeper 10 including a gutter broom assembly 52 having a right gutter broom 53 and a left gutter broom (not shown), a gutter cleaning head 47 including a cleaning head shroud 49 forming a gutter cleaning head chamber 54 which is capable of being vacu- umized, a vertically oriented gutter broom duct or air conduit 56 between the gutter cleaning head chamber 54 and the hopper 14, a conveyor mechanism 16, a conveyor housing or conduit 18, a rotary broom 20, an  elongated