Portable cutting device with on-board debris collection

Abstract

A portable cutting device having a cutting tool for cutting a material. The cutting device includes a motor driving the cutting tool and a shroud at least partially enclosing the cutting tool. The shroud defines a debris accumulation chamber for gathering debris created by the cutting tool cutting the material. An impeller is operatively coupled to the motor and driven by the motor to create suction pressure to draw the debris out of the debris accumulation chamber and into a collection bag.

1 . A cutting device comprising:
 a material cutting blade;   a shroud which at least partially encloses the blade and relative to which the blade is supported for relative movement;   a debris accumulation chamber within the shroud in fluid communication with the blade and into which material debris generated by the blade during cutting is received;   a source of vacuum in fluid communication with the debris accumulation chamber;   a pressure equalization chamber in fluid communication with the source of vacuum;   a plurality of vacuum conduits extending between the debris accumulation chamber and the pressure equalizing chamber, each conduit having an inlet and an outlet, the debris accumulation chamber having an opening into a conduit inlet, the pressure equalization chamber having an opening into a conduit outlet;   wherein airflow induced by the source of vacuum is drawn from the conduit inlets to the conduit outlets, material debris received in the debris accumulation chamber carried by the induced airflow toward the vacuum source and the pressure equalization chamber.   
     
     
         2 . The cutting device of  claim 1 , further comprising a vacuum housing having an exhaust port from which the induced airflow and material debris carried thereby exits the vacuum housing. 
     
     
         3 . The cutting device of  claim 2 , wherein the source of vacuum is contained in the vacuum housing, and the induced airflow and material debris carried thereby is expelled from the exhaust port under a pressure greater than the pressure in the pressure equalization chamber. 
     
     
         4 . The cutting device of  claim 2 , further comprising a collection container attached to the exhaust port and into which the induced airflow and material debris carried thereby is received, material debris received in the collection container retained therein. 
     
     
         5 . The cutting device of  claim 4 , wherein the collection container is a collection container having a wall through which the induced airflow received thereby passes. 
     
     
         6 . The cutting device of  claim 5 , wherein the collection container includes a porous inner container disposed within a porous outer container, the porosity of the inner container being less than the porosity of the outer container. 
     
     
         7 . The cutting device of  claim 1 , wherein each outlet of the plurality of vacuum conduits opens individually into the pressure equalization chamber. 
     
     
         8 . The cutting device of  claim 1 , wherein the inlets of the plurality of vacuum conduits are sequentially positioned along the path of blade travel within the shroud. 
     
     
         9 . The cutting device of  claim 8 , wherein the blade is a circular saw blade rotatably supported within the shroud, the perimeter of the saw blade having a circumferentially distributed plurality of teeth, the inlets of the vacuum conduits positioned at locations on the shroud that are sequentially passed by each saw blade tooth. 
     
     
         10 . The cutting device of  claim 9 , wherein the shroud substantially surrounds an upper portion of the circular saw blade and further comprising:
 a lower blade guard connected to the shroud, the lower blade guard having movement relative to the shroud between an extended position in which it substantially surrounds the perimeter of the lower portion of the saw blade, and at least one retracted position into which it is received in the debris accumulation chamber and at least partially exposes the perimeter of the lower portion of the saw blade, the lower blade guard having a surface in which is provided at least one aperture that is moved substantially into alignment with a vacuum conduit inlet in a retracted position; and   wherein material debris generated by the blade during cutting is carried with the induced airflow into the conduit inlet from a location between the saw blade perimeter and the blade guard through the aperture substantially aligned with the conduit inlet.   
     
     
         11 . The cutting device of  claim 1 , further comprising:
 a deck plate through which the blade extends and to which the shroud is connected;   a base plate attached to the deck plate and through which the blade extends, the base plate being positioned between the deck plate and a material-engaging portion of cutting blade;   the shroud and the base plate having selective cut depth positions in which the distances from the base plate to which the material-engaging portion of cutting blade extends are varied;   the shroud and the base plate having selective cut angle positions in which the relative angle between the base plate and the material-engaging portion of cutting blade is varied;   wherein the blade is disposed in a space defined by a surrounding wall extending between the base plate and the shroud that is substantially sealed against air leakage through the wall, throughout the operating ranges of cut depth and cut angle positions.   
     
     
         12 . The cutting device of  claim 11 , wherein substantially all of the air drawn by the vacuum source into the debris accumulation chamber substantially solely through an opening in the base plate through which the blade extends. 
     
     
         13 . The cutting device of  claim 11 , wherein the surrounding wall includes a expandable first bellows located between the deck plate and the shroud, the first bellows being correspondingly expanded and compressed between different cut depth positions with corresponding relative movement between the deck plate and the shroud. 
     
     
         14 . The cutting device of  claim 11 , wherein the base plate and the deck plate are pivotably attached to each other, and the surrounding wall includes a expandable second bellows located between the deck plate and the base plate, the second bellows being correspondingly expanded and compressed between different cut angle positions with corresponding relative movement between the deck plate and the base plate. 
     
     
         15 . The cutting device of  claim 11 , wherein the surrounding wall includes a transparent window located between the deck plate and the shroud, the cutting blade and material being cut visible to an operator through the window during cutting operations.