A power wheelchair includes a base frame and a seat frame. The base frame includes front and rear frame members, a pair of front wheels connected rotatably to the front frame member, a pair of rear wheels connected rotatably to the rear frame member, and a pair of mid-wheels connected rotatably to the front frame member and disposed between the front and rear wheels. The seat frame is connected to the rear frame member. The rear frame member is connected pivotally to the front frame member, and extends above the front frame member.

A tightening device for positioning a worktable of a machine tool to a base includes a saddle member disposed on the base, and a positioning carrier member carrying the worktable and movable relative to an abutment wall of the saddle member. An elongate adjusting member has a force-delivering end spaced apart from the abutment wall, and a middle threaded segment threadedly engaged with the positioning carrier member such that the force-delivering end is movable towards or away from the abutment wall. A force transmitting member is loosely connected to the positioning carrier member, and is configured such that a spiral force resulting from a screw-in movement is taken up by a proximate end thereof from the force-delivering end, and is transformed to a translation force that moves a distal end thereof to tightly engage the abutment wall.

A foldable frame assembly includes a base frame having a wheel-carrying end for mounting a wheel unit, a handgrip end, and an intermediate portion connected to a prop member so as to lift the base frame to a standing position. A tabletop has a front tabletop end pivoted to the intermediate portion for suspending a machine above the ground surface so as to enable a rear tabletop end to turn from a working position to a folded position. A bracing member has an anchoring end pivotally mounted on the wheel-carrying end, and a slidable end coupled with the rear tabletop end such that when the rear tabletop end is turned from the working position to the folded position, the slidable end is turned to be close to the intermediate portion. A rear locking unit is disposed to guard against movement of the slidable end.

A sawing path indicating circular saw includes a circular saw blade rotatably mounted on a saw blade shaft about a blade axis and having left and right major surfaces and a blade edge periphery, a seat member disposed on the saw blade shaft adjacent to the left major surface and rotated with the saw blade shaft, and an illuminating unit disposed on the seat member. Light emitted from the illuminating unit is directed radially and outwardly to project on a light reflecting area of the blade edge periphery and is reflected by the left major surface so as to create a bright region and a dim region on a surface of a workpiece, thereby forming a sharp demarcation line to indicate a sawing path of the saw blade.

A cutting apparatus includes a base, a blade-holding arm pivoted to the base through a pivot and co-rotatable with the pivot, a light-emitting unit pivoted to the blade-holding arm, and a position-adjusting unit including a first linkage that is secured to the pivot, and a second linkage that has two opposite ends which are respectively pivoted to the first linkage and the light-emitting unit.