Surface milling cutter with cutting inserts, a tool for holding a cutting insert with a cutting insert and method of machining a workpiece with a surface milling cutter holding cutting inserts

A surface milling cutter cutting insert of a surface milling cutter, which surface milling cutter has a central rotational axis, which surface milling cutter cutting insert is configured to be disposed at a predetermined distance form the central rotational axis of a surface milling cutter, and which surface milling cutter cutting insert is configured to rotate in a planar configuration substantially at a right angle to a rotational axis of a surface milling cutter,

• said surface milling cutter cutting insert comprising:
• an n-angle and n-sided base body where n is equal to or greater than six;
• said surface milling cutter cutting insert further comprising:
• a first roughing lip being configured to be disposed at a substantial lead angle, less than 90 degrees, to a surface milling cutter rotational axis;
• said first roughing lip being configured to be disposed to take a substantial deep cut in a workpiece;
• a first finishing lip configured to be disposed at an angle which, in operation, is substantially parallel to a surface of a deep cut made by said roughing lip;
• said first finishing lip being configured to finish, during operation, a surface of a workpiece by smoothing a surface of a deep cut made by said first roughing lip;
• said first finishing lip being disposed to immediately follow said first roughing lip;
• said first roughing lip and said first finishing lip being disposed immediately adjacent one another;
• said first roughing lip having a first end and a second end;
• said first finishing lip having a first end and a second end;
• said second end of said first roughing lip and said first end of said first finishing lip being disposed adjacent one another;
• said first roughing lip and said first finishing lip being configured, in operation to, form a first pair of lips;
• said first roughing lip being configured to be disposed to lead said first finishing lip, in operation, such that, said first roughing lip machines away a deep, rough, cut;
• said first finishing lip being configured and disposed to immediately follow, in operation, said first roughing lip to finish and smooth a deep rough cut made by said first roughing lip during operation;
• said first roughing lip and said first finishing lip forming a first apex angle therebetween;
• said first roughing lip having a first length and said first finishing lip having a length different from said first length;
• a second finishing lip having a first end and a second end;
• said second end of said second finishing lip being disposed adjacent said first end of said first roughing lip;
• said first roughing lip and said second finishing lip being disposed at a second apex angle;
• said second apex angle being smaller than said first apex angle;
• a second of said roughing lips and said second of said finishing lips being disposed immediately adjacent one another;
• said second roughing lip having a first end and a second end;
• said second finishing lip having a first end and a second end;
• said second end of said second roughing lip and said first end of said second finishing lip being disposed adjacent one another;
• said second roughing lip and said second finishing lip forming a second pair of lips, in operation, upon said second pair of lips being positioned in said front milling face for cutting;
• said second roughing lip being configured to be disposed to lead said second finishing lip, in machining operation, such that, said second roughing lip machines away a deep, rough, cut upon said second pair of lips being positioned in said front milling face for cutting;
• said second finishing lip, being configured to immediately follow, upon said second pair of lips being positioned in said front milling face for cutting, said second roughing lip to finish and smooth a deep rough cut made by said second roughing lip during operation;
• said second roughing lip and said second finishing lip forming a third apex angle therebetween;
• said second roughing lip having a second length and said second finishing lip having a length different from said second length;
• a third finishing lip having a first end and a second end;
• said second end of said third finishing lip being disposed adjacent said first end of said second roughing lip;
• said second roughing lip and said third finishing lip being disposed at a fourth apex angle;
• said fourth apex angle being different from said third apex angle;
• said third of said roughing lips and said third of said finishing lips being disposed immediately adjacent one another;
• said third roughing lip having a first end and a second end;
• said third finishing lip having a first end and a second end;
• said second end of said third roughing lip and said first end of said third finishing lip being disposed adjacent one another;
• said third roughing lip and said third finishing lip forming a third pair of lips upon said third pair of lips being positioned in said front milling face for cutting;
• said third roughing lip being configured to be disposed to lead said third finishing lip, in operation, such that, said third roughing lip machines away a deep, rough, cut;
• said third finishing lip being configured to immediately follow, in operation, said third roughing lip to finish and smooth a deep rough cut made by said third roughing lip during operation;
• said third roughing lip and said third finishing lip forming a fifth apex angle therebetween;
• said third roughing lip having a third length and said third finishing lip having a length different from said third length;
• said first, second, and third roughing lips having a same length;
• said first, second and third finishing lips having a same length, shorter than the length said first, second, and third roughing lips;
• said third finishing lip having a first end and a second end;
• said second end of said first finishing lip being disposed adjacent said first end of said third roughing lip;
• said first end of said third roughing lip being disposed adjacent said second end of said first finishing lip;
• said third roughing lip and said first finishing lip forming a sixth apex angle;
• said sixth apex angle being different from said fifth apex angle;
• said first apex angle, said third apex angle and said fifth apex angle being equal, and greater than said second apex angle, said fourth apex angle, and said sixth apex angle;
• said second apex angle, said fourth apex angle, and said sixth apex angle being equal;
• and
• each said apex angle being measured through the material of said insert and being less than 180 degrees and greater than 90 degrees.

A surface milling cutter having a central rotational axis, said surface milling cutter comprising:

• a tool carrying body with a front milling face at one end;
• at least one surface milling cutter cutting insert disposed at said front milling face, and at a predetermined distance from said central rotational axis;
• said at least one surface milling cutter cutting insert being disposed to rotate in a planar configuration substantially at a right angle to the rotational axis;
• said at least one surface milling cutter cutting insert comprising n-angled and n-sided base body where n is equal to or greater than six;
• each said at least one n-sided surface milling cutter cutting insert comprising n-edges disposed at apex angles, which apex angles are measured through the material of said insert, said apex angles being less than about 180 degrees and greater than about 90 degrees;
• said at least one surface milling cutter cutting insert comprising:
• a first roughing lip disposed at a substantial lead angle, to the rotational axis, which first cutting lip is configured and disposed to take a substantial deep cut in a workpiece;
• said lead angle of said roughing lips being less than 90 degrees;
• a first finishing lip disposed at an angle which is configured, in operation, to be substantially parallel to a surface of a deep cut made by said roughing lip, which said first finishing lip is configured to finish, during operation, a surface of a workpiece by smoothing a surface of a deep cut made by said first roughing lip;
• said first roughing lip having a first end and a second end;
• said first finishing lip having a first end and a second end;
• said second end of said first roughing lip and said first end of said first finishing lip being disposed adjacent one another;
• said first roughing lip and said first finishing lip form a first pair of lips;
• said first roughing lip being configured to be disposed to lead said first finishing lip, in operation, such that said first roughing lip machines away a deep, rough, cut;
• said first finishing lip being configured and disposed to immediately follow, in operation, said first roughing lip to finish and smooth a deep, rough, cut made by said first roughing lip during operation;
• said first roughing lip and said first finishing lip forming a first apex angle therebetween;
• said first roughing lip having a first length and said first finishing lip having a length different from said first length;
• a second finishing lip having a first end and a second end;
• said second end of said second finishing lip being disposed adjacent said first end of said first roughing lip;
• said first roughing lip and said second finishing lip forming a second apex angle therebetween;
• said second apex angle being smaller than said first apex angle;
• at least two additional roughing lips and at least one additional finishing lip, one of said at least one additional finishing lip being disposed between two of said at least two additional roughing lips;
• said roughing lips being of equal length;
• and
• said finishing lips being of equal length.

A method of machining a plane of a workpiece with a surface milling cutter cutting insert for machining a workpiece with an n-angled base body with n≧6, all n angles being less than 180°, whose n edges defining the n-angled base are alternately designed as finishing lips for finish-machining and as roughing lips for rough-machining of the workpiece, wherein each lip is arranged relative to its adjacent lips at different angles, so that the lips are alternately of different lengths, adjacent lips are arranged alternately at a large angle and a small angle relative to one another and the large angle being maximally 140°;

• said n edges lie in one plane;
• said large angle is at least 5° larger than the nth part of the angular sum of the n-angled base body;
• said roughing lip is arranged in a mounting position in a tool carrying body in an orientation at a defined lead angle to a machining plane, the angular sum of the lead angle and of the large angle being approximately 180°;
• said finishing lip has a minor-lip clearance to the securing plane;
• said finishing lip is designed as a wiper lip;
• said finishing lip extends along a curvature;
• said curvature is a circular curve with a radius, which lies in the range between 500 millimeters and 3000 millimeters;
• said cutting insert is provided for lead angles between 40° and 55°, in one embodiment example for a lead angle of 45°;
• said cutting insert is designed as a double-sided indexable insert with 2n lips;
• said opposing lips are connected in each case over a front face having two partial front faces arranged at a clearance angle and inwardly inclined towards one another;
• said cutting insert in combination with a tool for machining a workpiece, such as a milling cutter, with a tool carrying body, on which at least one cutting insert is secured;
• said tool carrying body has an insert seat with at least two front-face bearing faces, a holding pocket forming a clearance being provided between the bearing faces;
• said method comprising:
• at least one cutting insert, one of said roughing lips being oriented to a machining plane of the workpiece at a defined lead angle and engaging the workpiece during a feed motion of the tool, said finishing lip adjacent to said roughing lip simultaneously engaging the workpiece.