Patent ID: 8640685

Claim:
A concrete saw including a frame, a rotary power source, and a belt tensioning assembly, the assembly comprising: a blade shaft drive assembly including at least one lower rotatable sheave in operable engagement with a cutting blade, a rotatable blade shaft having provisions for rotating a cutting blade, a rotatable jack shaft oriented parallel to the blade shaft, and a plurality of gears operably engaging the blade shaft and the jack shaft, the jack shaft including the lower sheave which is engaged with the jack shaft; a positionable drive shaft assembly including at least one upper rotatable sheave in operable engagement with the rotary power source; at least one belt extending between and in operable engagement with the lower sheave and the upper sheave such that rotation of the upper sheave imparts rotation to the lower sheave; and an adjusting assembly having provisions for selectively changing the position of the drive shaft assembly relative to the blade shaft drive assembly thereby changing the distance between the lower sheave and the upper sheave.