Chop saw

A chop saw comprising:

• a powered saw blade,
• a saw carriage means supporting said saw blade and mounted for moving said blade toward and away from a workpiece,
• carriage drive means for moving said carriage means to feed said saw blade toward and away from and in a cutting stroke through said workpiece,
• and position-responsive speed control means directly responsive to an operating position of said carriage drive means and operated by operating means associated with said carriage drive means for varying the feed speed of said carriage means during the cutting stroke of said saw blade,
• log clamp means for clamping a log in a fixed position during said cutting stroke, said clamp means including a pair of opposed independently movable log-clamping arm means for gripping the opposite sides of said log adjacent to the cutting plane of said saw blade, and control means for automatically cycling said carriage drive means and said clamping arm means in sequence such that said clamping arm means grip said log before said saw blade begins its cutting stroke and release said log upon completion of said cutting stroke, said control means including clamp release means on said saw carriage means operable in response to movement of said carriage means to a predetermined retracted position to release said log-clamping arm means.

In a chop saw apparatus for cutting logs into variable lengths including a rotatable circular saw blade movable into and retractable from cutting engagement with a log by an oscillating saw carriage pivoted to a fixed base,

• a log-clamping means including a pair of separate and opposed log-clamping arms for gripping the opposite sides of a log while being cut by said saw blade,
• reversible fluid motor means for moving each log-clamping arm separately into clamping engagement with a log,
• and control means operable automatically to coordinate stroking movement of said saw carriage with clamping movement of said clamp arms such that said clamp arms grip a log before said saw blade begins cutting said log and release said log after withdrawal of said saw blade therefrom,
• said control means including fluid control circuit means for said fluid motor means and fluid control valve means in said circuit means, said control valve means being movable to a first position to cause said fluid motor means to close said arms against a log before said saw blade enters said log, said control valve means being movable to a second position to cause said fluid motor means to open said arms and release said log in response to movement of said saw blade away from said log to a predetermined retracted position.

In a chop saw apparatus for cutting elongate workpieces into variable lengths including a rotatable circular saw blade movable into and retractable from cutting engagement with a workpiece by an oscillating saw carriage pivoted to a fixed base,

• a clamping means including a pair of separate and opposed clamping arms for gripping the opposite sides of a workpiece while being cut by said saw blade,
• a pair of reversible fluid motor means, one for moving each clamping arm separately into clamping engagement with the workpiece,
• and control means operable automatically to coordinate stroking movement of said saw carriage with clamping movement of said clamp arms such that said clamp arms grip the workpiece before said saw blade begins cutting the workpiece and releases the workpiece after withdrawal of said saw blade therefrom,
• said control means including a separate fluid control circuit for each said fluid motor means, each said control circuit including a control valve movable between three positions including a flow-blocking position, a clamp-closing position and a clamp-opening position, and control valve-operating means operable sequentially, first to move each control valve from its flow-blocking position to its clamp-closing position to apply clamping pressure to the workpiece before said saw blade enters the workpiece, second to move each control valve from its clamp-closing position to its flow-blocking position while said clamp arms apply clamping pressure to the workpiece to lock said clamp arms on the workpiece during the cutting stroke of the saw blade, and third to move each control valve from its flow-blocking position to its clamp-opening position to release the workpiece after the saw blade has completed its cutting stroke.