Street sweeper with dust control

Abstract

Street sweeper having dust control from two or more cleaning 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 filter cleaning.

1 . A road sweeper with dust control for cleaning a surface, the road sweeper comprising: 
 a. a vacuum source;    b. a main road surface cleaning head in fluid communication with the vacuum source, and having an opening adjacent a surface intended to be cleaned;    c. at least a first gutter cleaning head in fluid communication with the vacuum source, and having an opening adjacent a gutter area intended to be cleaned;    d. a hopper for collecting dust, dirt, and debris;    e. a conveying mechanism in fluid communication with the vacuum source, and in communication with the road surface cleaning head for transporting dust, dirt, and debris from the main road surface cleaning head to the hopper; and,    f. a common air filtration mechanism for substantially removing airborne dust in air drawn from the main cleaning head opening and the gutter cleaning head opening by way of the vacuum source.    
   
   
       2 . The road sweeper of  claim 1 , wherein: 
 a. the vacuum source concurrently establishes, 
 (1) a first airflow following a first airflow path from the main road surface cleaning head, through the vacuumized conveying mechanism, and entering the hopper, thereby vacuumizing, at least in part, the main road surface cleaning head, the conveying mechanism, and the hopper; and,  
 (2) a second airflow following a second airflow path from the gutter cleaning head for vacuumizing, at least in part, the gutter cleaning head; and,  
   b. the air filtration mechanism is in the path of the first and second airflow paths for filtering air passing therethrough so that any airborne dust in the first and second air flow paths is substantially blocked.    
   
   
       3 . The road sweeper of  claim 1 , wherein: 
 a. the main road surface cleaning head includes an elongated rotary broom having a rotational axis substantially aligned with the road surface;    b. the gutter cleaning head includes a rotary broom having an axis of rotation generally transverse to the road surface; and,    c. the vacuumized conveying mechanism is a conveyor mechanism for transporting the dirt and debris to the hopper, and where the conveyor mechanism is surrounded at least in part by a vacuumized housing having an open end in communication with the main road surface cleaning head, and a second open end in communication with the hopper.    
   
   
       4 . The road sweeper of  claim 1 , wherein: 
 a. the main road surface cleaning head includes a pressurized air inlet and an air outlet whereby debris entrained with and carried along by the air being conducted through the main road surface cleaning head exits therefrom through the conveying mechanism; and    b. the conveying mechanism is an air conduit for transporting any dirt and debris to the hopper.    
   
   
       5 . The road sweeper of  claim 1 , further including an air intake plenum having, 
 a. one or more first inlet ports in communication with an air chamber formed by the hopper;    b. at least one second inlet port in direct communication with the gutter cleaning head through an air conduit coupled thereto; and    c. a plenum air exit port in communication with the vacuum source.    
   
   
       6 . The road sweeper of  claim 5 , wherein: 
 a. the air filtration mechanism is mounted within, at least in part, the air plenum and includes a mechanism for loosening any dirt therewith to fall with gravity; and    b. the air plenum includes an adjustable bottom portion open to the hopper in a first configuration, and substantially closed relative to the hopper in a second configuration, so that any loosened dirt may fall into the hopper when the adjustable bottom portion is in the open condition.    
   
   
       7 . The road sweeper of  claim 6 , wherein the plenum adjustable bottom portion includes flap valves operable in a first condition for sealing the bottom portion of the air plenum relative to the hopper, and in a second condition for opening the bottom portion open to the hopper.  
   
   
       8 . The road sweeper of  claim 7 , wherein the flap valves are automatically operated by the presence or absence of airflow established by the vacuum source.  
   
   
       9 . The road sweeper of  claim 2 , wherein the first and second airflow paths continue to the outside environment, and the air filtration mechanism substantially blocks any airborne dust in the first and second air flow paths from exhausting out to the outside environment.  
   
   
       10 . The road sweeper of  claim 6 , wherein the filtration mechanism includes: 
 a. a porous filter for passing air therethrough and depositing any airborne dust therewith on the filter; and    b. a filter shaker mechanism for shaking the collected dust on the porous filter to fall with gravity.    
   
   
       11 . The road sweeper of  claim 6 , wherein the filtration mechanism includes a centrifugal dust collection system for passing air therethrough and collecting any airborne dust therewith.  
   
   
       12 . A street sweeper, comprising: 
 a. a framework for mounting to a truck chassis;    b. a vacuum source carried by the framework, the vacuum source including a plenum, a vacuum source, a hopper depending from the plenum, a filter mechanism, and an adjustable plenum being sealable in a first configuration and open in a second configuration;    c. a first elongated cleaning head in fluid communication with the vacuum source, the first elongated cleaning head opening adjacent a roadway surface to be swept and about a main rotary broom for vacuumized removal of airborne dust, and having a connected conveyor housing providing fluid communication between the first elongated cleaning head and the vacuum source; and,    d. a second cleaning head in fluid communication with the vacuum source, the second cleaning head opening adjacent a roadway gutter to be cleaned and about a gutter broom located beneath the sweeper truck chassis for vacuumized removal of airborne dust, and having a connected duct providing fluid communication between the second cleaning head and the vacuum source.    
   
   
       13 . The dust control system for a street sweeper of  claim 12 , wherein the filter shaker mechanism includes a cam.  
   
   
       14 . The dust control system for a street sweeper of  claim 13 , wherein the cam lifts a rod in contact with the filter.  
   
   
       15 . The dust control system for a street sweeper of  claim 14 , wherein the rod lifted by the cam is one of a plurality of positionable rods located at lower folds of the filter.  
   
   
       16 . The dust control system for a street sweeper of  claim 12 , wherein the filter is held within the plenum by a plurality of fixed rods extending across a top region of the plenum during operation of the shaker mechanism.  
   
   
       17 . The dust control system for a street sweeper of  claim 12 , wherein the fan is non-operational during operation of the filter shaker mechanism.  
   
   
       18 . The dust control system for a street sweeper of  claim 12 , wherein the automatic flexible airflow operated flap valves of the orificed plenum array open the bottom of the plenum, in the second configuration, when the fan is non-operational.  
   
   
       19 . The dust control system for a street sweeper of  claim 12 , wherein the automatic flexible airflow operated flap valves of the orificed plenum array seal the bottom of the plenum, in the first configuration, when the fan is operational.  
   
   
       20 - 24 . (canceled)  
   
   
       25 . A street sweeper, comprising: 
 a. a framework for mounting to a truck chassis;    b. a vacuum source carried by the framework;    c. a plenum having an adjustable bottom sealing the bottom of the plenum in a first configuration and opening the bottom of the plenum in a second configuration;    d. a hopper depending from the plenum;    e. a filter and filter shaker mechanism mounted in the plenum and below the fan;    f. a first elongated cleaning head in fluid communication with the vacuum source, the first elongated cleaning head opening adjacent a roadway surface to be swept and about a main rotary broom for vacuumized removal of airborne dust;    g. a connected conveyor conduit providing fluid communication between the first elongated cleaning head and the vacuum source; and,    h. at least one second cleaning head in fluid communication with the vacuum source, the at least one second cleaning head opening adjacent a roadway gutter to be cleaned and about a gutter broom located beneath the sweeper truck chassis for vacuumized removal of airborne dust, and having a connected duct providing fluid communication between the second cleaning head and the vacuum source.