Dipper stick cutter

A wood cutter combinable with a dipper stick of an excavator or back hoe having a hydraulically operated curl cylinder on the dipper stick, the cutter comprising:

• a pair of cutting blades pivotally movable to open and close in a plane transverse to a generally vertical plane of movement of the dipper stick;
• the blades being oriented to face toward a boom side of the dipper stick;
• a link arm connected to each blade via a universal joint;
• the link arms being pivotally connected to a freely rotatable link bar;
• and
• motion of the curl cylinder in the generally vertical plane of the dipper stick being transmitted to the link bar so that an extending motion of the curl cylinder pushes the link bar toward the blades, causes the link arms to spread apart at their connections to the blades and moves the blades to a closed position effecting a cut, and so that a retracting motion of the curl cylinder pulls the link bar away from the blades, causes the link arms to move toward each other at their connections to the blades and moves the blades to an open position.

A dipper stick cutter operable by a curl cylinder on a dipper stick on which the cutter can be mounted, the cutter comprising:

• a pair of pivotally mounted cutting blades that are movable to an open position to straddle woodl to be cut and are movable to a closed position to cut wood;
• a link system transmitting extending and retracting motion of a curl cylinder on the dipper stick to operate the blades;
• the link system including a pair of link arms connected respectively to the blades via universal joints;
• the link arms being pivotally connected to a link bar;
• an activator moved in response to the curl cylinder;
• and
• movement of the activator being transmitted to the link bar to move the link arms to open and close the blades for cutting.

A dipper stick link system operating a pair of pivotally mounted dipper stick cutter blades, the combination of the link system and the cutter blades comprising:

• a freely rotatable link bar;
• a pair of link arms connected respectively to the link bar so that each of the link arms can pivot relative to the link bar;
• the link arms being respectively connected to the blades by a pair of ball joints;
• the link bar being arcuately movable toward and away from the blades;
• and
• during arcuate movement of the link bar, the link arms pivot relative to the link bar to spread apart the ball joint connections of the link arms to the blades to pivot the blades to one position as the link bar pushes toward the blades, and to move the ball joint connections of the link arms to the blades toward each other to pivot the blades to a second position as the link bar pulls away from the blades.