Method for generating offset surface data

Claim 1

A method for defining a path on a target surface for a milling tool having a blade (MB) by generating offset surface data (S OFF ) using a free surface formed with at least two patches (S (u,v) ) sequentially interconnected at a boundary line where there is non-continuity of tan­gential planes, characterized in that the method comprising the steps of: (a) generating first surface data (S OFF ) representing a first offset surface opposing the patches and second surface data (C OFF representing a second offset surface formed at a position separated by a first predetermined distance from a position ont he boundary line of the patches; and (b) interpolating the second surface data (C OFF ) for the first surface data (S OFF ) so that when the tool traverses the boundary line, a tool path can be generated wherein the tool blade edge is prevented from unnecessarily milling the target surface.

Claim 2

A method for defining a path on a target surface for a milling tool having a blade (MB) by generating offset surface data (S OFF ) using a free surface formed with at least two patches (S (u,v) ) sequentially interconnected at a boundary line where there is non-continuity of tan­gential planes, characterized in that the method comprising the steps of: (a) generating first surface data (S OFF ) representing a first offset surface opposing the patches and second surface data (C OFF representing a second offset surface formed at a position separated by a first predetermined distance from a position ont he boundary line of the patches; and (b) interpolating the second surface data (C OFF ) for the first surface data (S OFF ) so that when the tool traverses the boundary line, a tool path can be generated wherein the tool blade edge is prevented from unnecessarily milling the target surface.

Claim 6

A method for defining a path on a target surface for a milling tool having a blade (MB) by generating offset surface data using a free surface formed with at least two patches (S (u,v)1 , SS (u,v)2 ) sequentially interconnected at a boundary line where there is non-continuity of the tangential planes, characterized in that there is a first discontinuous end surface represented by first offset surface data (S OFF1 ) corresponding to a first one of the patches (S (u,v)1 ) at each control point representing a common boundary (COM12) of the first one (S (u,v)1 ) of the patches and a second one (S (u,v)2 ) of the patches, and in that the method comprises the steps of: (a) deriving an outwardly directed first vector a normal to the first discontinuous end surface and simultaneously deriving a second vector (C) comprising a normal line vector represented by second offset surface data (S OFF2 ) corresponding to the second one of the patches (S (u,v)2 ); and (b) deriving a position of intersection between a plane of the second vector and the first vector so that that the intersection position data is interpolated as a third offset surface data (C OFF ) at a discontinuous space generated between the first and second offset surface data.

Claim 7

A method for defining a path on a target surface for a milling tool having a blade (MB) by generating offset surface data using a free surface formed with at least two patches (S (u,v)1 , SS (u,v)2 ) sequentially interconnected at a boundary line where there is non-continuity of the tangential planes, characterized in that there is a first discontinuous end surface represented by first offset surface data (S OFF1 ) corresponding to a first one of the patches (S (u,v)1 ) at each control point representing a common boundary (COM12) of the first one (S (u,v)1 ) of the patches and a second one (S (u,v)2 ) of the patches, and in that the method comprises the steps of: (a) deriving an outwardly directed first vector a normal to the first discontinuous end surface and simultaneously deriving a second vector (C) comprising a normal line vector represented by second offset surface data (S OFF2 ) corresponding to the second one of the patches (S (u,v)2 ); and (b) deriving a position of intersection between a plane of the second vector and the first vector so that that the intersection position data is interpolated as a third offset surface data (C OFF ) at a discontinuous space generated between the first and second offset surface data.

Claim 8

A method for defining a path on a target surface for a milling tool having a blade (MB) by generating offset surface data using a free surface formed with at least three patches (S (u,v)1 , S (u,v)2 , S (u,v)3 interconnected in pairs at separate boundary lines where there is non-con­tinuity of the tangential planes, characterized in that the method comprising the steps of: (a) generating first surface data (S OFF1 ) representing a first offset surface opposing one of the patches of a first pair of the patches and second surface data (C OFF ) representing a second offset surface formed at a position separated by a first predetermined distance from a position on the boundary line of the first pair of the patches; (b) interpolating the second surface data (C OFF ) for the first surface data (S OFF1 ) so that when the tool traverses the boundary line between the first pair of the patches, a tool path can be generated wherein the tool blade edge is prevented from unnecessarily milling the target surface; and (c) repreating steps (a) and (b) for each of the other pairs of patches .

Claim 9

A method for defining a path on a target surface for a milling tool having a blade (MB) by generating offset surface data using a free surface formed with at least three patches (S (u,v)1 , S (u,v)2 , S (u,v)3 interconnected in pairs at separate boundary lines where there is non-con­tinuity of the tangential planes, characterized in that the method comprising the steps of: (a) generating first surface data (S OFF1 ) representing a first offset surface opposing one of the patches of a first pair of the patches and second surface data (C OFF ) representing a second offset surface formed at a position separated by a first predetermined distance from a position on the boundary line of the first pair of the patches; (b) interpolating the second surface data (C OFF ) for the first surface data (S OFF1 ) so that when the tool traverses the boundary line between the first pair of the patches, a tool path can be generated wherein the tool blade edge is prevented from unnecessarily milling the target surface; and (c) repreating steps (a) and (b) for each of the other pairs of patches .

Claim 13

A method for defining a path on a target surface for a milling tool having a blade (MB), characterized by generating first, second and third offset surface data using a free surface formed with at least first, second, and third patches as a target to be milled, the patches being sequentially interconnected at boundary lines where there is non-continuity of the tangential planes, and in that the method comprising the steps of: (a) deriving first, second, and third normal line vectors (A, B, C) on points corresponding to common points to the first, second, and third offset surface data of points corresponding to the common points from among the offset surface data of the mutually connected first, second, and third patches; (b) deriving an intersection of planes of the first, second, and third normal line vectors; (c) interpolating the position data for the intersection as the offset surface data at a discontinuous space generated at the corner.

Claim 14

A method for defining a path on a target surface for a milling tool having a blade (MB), characterized by generating first, second and third offset surface data using a free surface formed with at least first, second, and third patches as a target to be milled, the patches being sequentially interconnected at boundary lines where there is non-continuity of the tangential planes, and in that the method comprising the steps of: (a) deriving first, second, and third normal line vectors (A, B, C) on points corresponding to common points to the first, second, and third offset surface data of points corresponding to the common points from among the offset surface data of the mutually connected first, second, and third patches; (b) deriving an intersection of planes of the first, second, and third normal line vectors; (c) interpolating the position data for the intersection as the offset surface data at a discontinuous space generated at the corner.