Working tool operation range limiting apparatus

A working tool operation range limiting apparatus for use with a machine having a movable working arm, a working tool pivotally attached to one end of the working arm, said apparatus comprising:

• first means for designating at least one hazard region in an operation range space of the working tool;
• and
• second means for decelerating the velocity of the working tool as the working tool approaches each of the at least one hazard region and for stopping movement of the working tool toward the respective hazard region just before the working tool would otherwise enter the respective hazard region;
• wherein said first means comprises means for designating a hazard region and a corresponding decelerating region for at least one of upward, downward, forward, and sideward positions of the working tool;
• and
• wherein said second means comprises means for providing a predetermined decelerating pattern, means for determining a selected velocity of the working tool, means for comparing the thus determined selected velocity of the working tool with the predetermined decelerating pattern, and means for decelerating the working tool velocity when the working tool enters a decelerating region and the thus determined selected velocity is greater than a corresponding portion of the predetermined decelerating pattern.

A working tool operation range limiting apparatus for use with a machine having a movable working arm, a working tool pivotally attached to one end of the working arm, said apparatus comprising:

• first means for designating at least one hazard region in an operation range space of the working tool;
• and
• second means for decelerating the velocity of the working tool as the working tool approaches each of the at least one hazard region and for stopping movement of the working tool toward the respective hazard region just before the working tool would otherwise enter the respective hazard region;
• wherein said second means comprises means for providing a predetermined decelerating pattern, means for determining the velocity of the working tool, means for comparing the thus determined velocity of the working tool with the predetermined decelerating pattern, and means for decelerating the working tool velocity when the working tool enters a decelerating region and the working tool velocity is greater than a corresponding portion of the predetermined decelerating pattern.

A method of limiting the operation range of a working tool on a machine having a movable working arm and the working tool pivotally attached to one end of the working arm, said method comprising the steps of:

• designating at least one hazard region in an operation range space of the working tool,
• operating the working tool at a velocity,
• controlling the velocity of the working tool to decelerate the velocity of the working tool whenever the working tool approaches any one of said at least one hazard region, and
• stopping the movement of the working tool toward the respective hazard region just before the working tool would otherwise enter the respective hazard region;
• wherein the step of designating at least one hazard region comprises designating a hazard region and a corresponding decelerating region for at least one of upward, downward, forward, and sideward positions of the working tool, and storing values representing each thus designated hazard region and each thus designated corresponding decelerating region;
• wherein the step of controlling comprises providing a predetermined decelerating pattern, determining a selected velocity of the working tool toward a respective hazard region, comparing the thus determined selected velocity of the working tool with the predetermined decelerating pattern, and decelerating the working tool velocity when the working tool enters a decelerating region and the selected velocity of the working tool is greater than a corresponding portion of the predetermined decelerating pattern.

A working tool operation range limiting apparatus for use with a machine having a movable working arm, a working tool pivotally attached to one end of the working arm, said apparatus comprising:

• first means for designating at least one hazard region in an operation range space of the working tool;
• and
• second means for decelerating the velocity of the working tool as the working tool approaches each of the at least one hazard region, and for stopping movement of the working tool toward the respective hazard region just before the working tool would otherwise enter the respective hazard region;
• wherein said second means comprises means for providing a predetermined restoring pattern of a working tool velocity for moving the working tool away from the respective hazard region, means for comparing a velocity of the working tool away from the respective hazard region with the predetermined restoring pattern, and means for driving the working tool away from the respective hazard region in accordance with the smaller of the velocity of the working tool away from the respective hazard region and a corresponding portion of the predetermined restoring pattern.