Sheet cutting device and cutting method

A sheet cutting device for cutting a sheet stuck on an adherend on a sticking table, said device comprising:

• a control device;
• a robot body having a plurality of arm members rotatably connected with each other in series;
• and
• a cutter blade directly supported by a last arm member of the arm members on a free-end of the robot body,
• wherein said robot body supports said cutter blade so as to adjust a posture of the cutter blade when cutting the sheet along an outer periphery of said adherend,
• wherein said control device is configured to actively control the robot body to hold said posture of said cutter blade in a sheet cutting operation for cutting said sheet in any cutting direction, on a surface of said adherend, to maintain
• (i) a toe-in angle with which a center line of the cutter blade is inclined with respect to the cutting direction as viewed from the top in the cutting direction, and a blade edge of the cutter blade is positioned closer to the outer periphery of the adherend than a back portion of the cutter blade,
• (ii) a camber angle with which the center line of the cutter blade is inclined as viewed from the front in the cutting direction, and a front end portion of the cutter blade is positioned at the outer side than a base portion of the cutter blade, and
• (iii) a caster angle with which the center line of said cutter blade is inclined in the cutting direction as viewed from the side in the cutting direction, and an angle formed between said sheet and the blade edge is kept at an acute angle,
• wherein
• the entire robot body including all said arm members is rotatable about a first rotational axis of a first arm member of the arm members,
• the first rotational axis is perpendicular to the sticking table on which the adherend is to be disposed, and
• the first rotational axis is not coaxially arranged with respect to the sticking table and the adherend to be disposed thereon
• wherein the plurality of arm members further comprises:
• a second arm member which is rotatable about a second axis perpendicular to the first axis;
• a third arm member which is rotatable about a third axis parallel to the second axis;
• a fourth arm member which is rotatable about a fourth axis perpendicular to the third axis;
• a fifth arm member which is rotatable about a fifth axis perpendicular to the fourth axis;
• and
• the last arm member which is rotatable about a sixth axis perpendicular to the fifth axis;
• and
• wherein said first to last arm members are continuously connected.