ABSTRACT Street sweeper having dust control from two or more clean- ing heads with one air source where one fan provides vacuum for a centrally located rotating broom which is surrounded by a vacuumized chamber and for a gutter broom which is surrounded by a vacuumized chamber。 A plenum having a unique valving system and a filter shaker mechanism provides for filter cleaning and for a dirt and debris path from the plenum to a hopper bottom during filter82123

STREET SWEEPER WITH DUST CONTROL

CROSS REFERENCES TO RELATED APPLICATIONS

BACKGROUND OF THE INVENTION[0002]   1。 Field of the  Invention[0003] The present invention pertains to a street sweeper, and more particularly, to dust control from two or more cleaning heads with one air  source。

[0004]   2。 Description  of the Prior Art

[0005] Prior art dust control systems for road sweepers frequently include the use of water which wets the debris and dirt on the road surface to prevent dust from becoming airborne during the sweeping process。 In such systems, water must be provided at various sweeper locations, such as, but not limited to, the main rotary broom and the gutter brooms。 Water systems often just wet down debris and dirt whereby the wetted debris and dirt may still reside on the wetted roadway after sweeping rather than having been carried into the conveyor or hopper。 The use of vacuum systems instead of water systems to carry off generated airborne dust is often desirable in that no wetted debris or dirt is presented to be left behind after sweeping。 Vacuum systems generally use a separate dedicated fan to draw dust from the region of the main rotary broom and a separate dedicated fan to draw dust from the region of the gutter brooms。 The use of separate and dedicated fans results in excessive space being occupied and adds expense to the fabrication processes。 The use of separate and dedicated fans can also produce a flow problem where the vacuum pro- duced by one fan may interfere or conflict with the vacuum of another fan when entering a common chamber or plenum。

[0006] Another problem encountered in dry dust control systems is that of clogging of a filter located prior to the fan。 Filter clogging is detrimental to the removal of dust before discharging air from the fan to the atmosphere and can slow and hinder the vacuuming process significantly。 Cleaning or exchanging a filter can be a laborious and time-consuming process resulting in poor overall e8iciency。

SUMMARY OF THE INVENTION

[0007] The general purpose of the present invention is to provide a street sweeper having dust control from two or more cleaning heads with one air vacuum source in a road sweeper, as well as a dust hltration system which can be readily cleaned on site without the removal of filtration components and without other extraordinary measures。 The present invention can be incorporated for use along a substantially planar surface, such as a road where the term road can mean any surface within a manufacturing facility, such as a tiled or concrete paved surface or the like, and can also be utilized along a common roadway。 In the present invention, a single fan is mounted to a plenum in the upper region of a truck-mounted hopper to provide vacuum for dust control。 A litter mechanism and a filter shaker mecha- nism mount just below the fan in the upper region of the plenum。  The  bottom  of  the  plenum  includes  an orificed

plenum array having a plurality of automatic flexible airflow operated flap valves which are closed during the sweeping operation to seal the bottom of the plenum。

[0008] Inlet passageways or ports are located about the plenum for vacuumized airflow into the plenum for subse- quent filtration。 Filtration can be any porous filter and centrifugal system or the like。 One such passageway, a lower inlet port, is located on and extends from the bottom of the plenum and connects to a gutter broom air conduit which communicates with a gutter cleaning head including a cleaning head shroud forming a cleaning head chamber capable of being vacuumized and being located beneath the sweeper truck chassis for vacuumized removal of airborne dust。 Additionally, appropriately sized upper inlet ports located on the upper and rear side of the plenum commu- nicate to the interior of the hopper and to a connected conveyor housing or conduit and thence to an elongated cleaning head including an elongated cleaning head shroud forming an elongated cleaning head chamber which can be vacuumized which is located about the main rotary broom for vacuumized removal of airborne dust。