Centerless saw device

Abstract

The present invention generally pertains to a saw device. More particularly, the present invention relates to a handheld centerless saw. The saw comprises a frame and a pair of driving rollers mounted to the frame for rotation. The saw also comprises an annular blade mounted between the drive rollers and functionally engaged thereby, where the blade defines frontward and backward hemispheres. At least two guide wheels are mounted to the frame, the guide wheels being positioned in the backward hemisphere of the blade. The guide wheels are operatively engaging the inner circular edge of the blade. A drive assembly mounted to the frame is operable for urging the countersense rotation of drive rollers, thereby causing rotation of the blade.

1 . A centerless saw device comprising:
 a frame;   at least a first and a second drive rollers mounted to said frame for rotation about first and second parallel rotation axes;   an annular blade mounted between said first and second drive rollers and frictionally engaged thereby, said annular blade defining frontward and backward hemispheres;   at least two guide wheels mounted to said frame, said guide wheels being positioned in said backward hemisphere of said annular blade and operatively engaging the inner circular edge thereof; and   a drive assembly mounted to said frame for urging rotation of said first and second drive rollers, thereby urging rotation of said annular blade.   
   
   
       2 . The centerless saw device of  claim 1 , wherein said device comprises a handheld saw device. 
   
   
       3 . The centerless saw device of  claim 1 , wherein said device comprises a table saw device. 
   
   
       4 . The centerless saw device of  claim 1 , wherein said device comprises a compound saw device. 
   
   
       5 . The centerless saw device of  claim 1 , wherein said drive assembly is adapted for driving a countersense rotation of said drive rollers in a 1:1 ratio. 
   
   
       6 . The centerless saw device of  claim 1 , wherein said drive assembly comprises a motor and a transmission operatively coupled to said motor. 
   
   
       7 . The centerless saw device of  claim 6 , wherein said motor is selected from a group consisting of a gas motor, an electric motor and a hydraulic motor. 
   
   
       8 . The centerless saw device of  claim 6 , wherein said transmission comprises a spur gear assembly for operatively connecting said motor to said first and second drive rollers. 
   
   
       9 . The centerless saw device of  claim 8 , wherein said spur gear assembly comprises a first spur gear operatively connected to said motor and to said first drive roller for rotation about said first rotation axis and a second spur gear operatively connected to said second drive roller, said second spur gear operatively engaging said first spur gear such that rotation thereof drives countersense rotation of said second spur gear about said second rotation axis. 
   
   
       10 . The centerless saw device of  claim 8 , wherein said spur gear is pivotably mounted to said frame, the pivoting of said spur gear in one direction improving a frictional engagement between said first and second drive rollers and said annular blade. 
   
   
       11 . The centerless saw device of  claim 10 , wherein said spur gear assembly is pivotable about said first rotation axis of said first spur gear. 
   
   
       12 . The centerless saw device of  claim 9 , wherein said transmission further comprises a bevel gear assembly for operatively connecting said first spur gear to said motor. 
   
   
       13 . A centerless cutting assembly comprising:
 a frame;   at least a first and a second drive rollers mounted to said frame for rotation about first and second parallel rotation axes;   an annular blade mounted between said first and second drive rollers and frictionally engaged thereby, said annular blade defining frontward and backward hemispheres;   at least two guide wheels mounted to said frame, said guide wheels being positioned in said backward hemisphere of said annular blade and operatively engaging the inner circular edge thereof; and   a transmission mounted to said frame for urging rotation of said first and second drive rollers, thereby urging rotation of said annular blade.   
   
   
       14 . The centerless cutting assembly of  claim 13 , wherein said transmission comprises a spur gear assembly for operatively connecting said first and second drive rollers to a motor. 
   
   
       15 . The centerless cutting assembly of  claim 14 , wherein said spur gear assembly comprises a first spur gear operatively connectable to said motor and to said first drive roller for rotation about said first rotation axis and a second spur gear operatively connected to said second drive roller, said second spur gear operatively engaging said first spur gear such that rotation thereof drives countersense rotation of said second spur gear about said second rotation axis. 
   
   
       16 . The centerless cutting assembly of  claim 15 , wherein said spur gear is pivotably mounted to said frame, the pivoting of said spur gear in one direction increasing frictional engagement between said first and second drive rollers and said annular blade. 
   
   
       17 . The centerless cutting assembly of  claim 16 , wherein said spur gear assembly is pivotable about said first rotation axis of said first spur gear. 
   
   
       18 . The centerless cutting assembly of  claim 17 , wherein said transmission further comprises a bevel gear assembly for operatively connecting said first spur gear to said motor. 
   
   
       19 . A centerless saw device comprising:
 a frame;   at least a first and a second driving rollers mounted to said frame for rotation about first and second parallel rotation axes, said first and second rollers being positioned to define a space therebetween and being operable to rotate countersense from one another about, each of said first and second drive rollers comprising a curved face;   an annular blade mounted between said curved faces of said drive rollers, said annular blade comprising a first annular face, a second opposed annular face, an inner curved edge and an outer curved edge, said curved face of said first roller frictionally engaging said first face of said annular blade and said second roller frictionally engaging said second face of said annular blade for driving said rotation of said annular blade about a third rotation axis, perpendicular to said first and second rotation axes;   at least two guide wheels mounted to said frame between said third rotation axis and said drive rollers, said guide wheels being rotatable about fourth and fifth rotation axes parallel to said third rotation axis, each guide wheel comprising an annular recess aligned with said space defined between said drive rollers and receiving therein said inner edge of said annular blade; and   a drive assembly mounted to said frame and operable for urging the countersense rotation of said at least first and second drive rollers.   
   
   
       20 . The saw device of  claim 19 , wherein said annular blade comprises at least one circular recess defined in at least one of said first and second face and at least one of said first and second drive roller comprises an annular protrusion extending from said curved face, said protrusion being receivable in said circular recess of said annular blade.