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US 7,451,013 B2Granted
Engagement milling
AssigneeSurfware, Inc.
InventorsGlenn Coleman, Alan Diehl, Robert B. Patterson
Life of this patent
Estimating the term…
Abstract
A method for generating, by a direct process, a tool path for milling a region of a workpiece by a milling cutter is disclosed. The tool path consists of one or more passes. The method includes the steps of storing a maximum engagement of the milling cutter and defining each one of the one or more passes such that a value of the engagement, when traversing each one of the one or more passes, does not exceed the maximum value of engagement.
Claims42
A method for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including one or more passes, the method comprising the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes,
- wherein the region is circular and wherein the one or more passes comprise a plurality of concentric circles, and wherein a radius of each one of the concentric circles is determined such that an engagement of the milling cutter milling each one of the concentric circles is substantially equal to the predetermined value of engagement, further including the steps of:
- (a) defining a largest one of the concentric circles on a first boundary;
- (b) determining if a smallest one of the concentric circles coincides with a second boundary;
- and
- (c) if the smallest concentric circle does not coincide with the second boundary within a predetermined value, selecting an engagement for determining the radius of each one of the concentric circles which is incrementally smaller than the predetermined value of engagement and repeating steps b and c until the smallest concentric circle coincides with the second boundary within the predetermined value.
6 more elements
A method for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including of one or more passes, the method comprising the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the at least one tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes, wherein the region has first, second and third sides, the first side being a current in-process material boundary and the second and third sides being non-parallel part or material boundaries, the first side meeting at its respective ends, the second and the third sides, and wherein each one of the one or more passes successively advances into the region, the method for computing the shape of at least one of the one or more passes comprising:
- determining a radius of curvature and a center of the current in-process material boundary;
- and
- determining a radius of curvature and a center for each one of the advancing passes based on the radius of curvature and the center of the current in-process material boundary, a half angle representative of the intersection of tangents to the second and the third sides and the predetermined value of engagement.
4 more elements
A method for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including of one or more passes, the method comprising the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the at least one tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes, wherein the region has first, second and third sides, the first side being a current in-process material boundary and the second and third sides being parallel part or material boundaries, the first side meeting at its respective ends, the second and the third sides, and wherein each one of the one or more passes successively advances into the region, the method for computing the shape of at least one of the one or more passes comprising:
- determining a radius of curvature and a center of the current in-process material boundary;
- and
- determining a radius of curvature and a center for each one of the advancing passes based on only the radius of curvature and the center of the current in-process material boundary, the size of the milling cutter and the predetermined value of engagement.
4 more elements
A method for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including of one or more passes, the method comprising the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the at least one tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes,
- wherein the tool path is perpendicular to the rotational axis of the milling cutter and enters the workpiece from outside a material boundary at a predetermined attitude, the method further including the steps of:
- defining a location of a starting point outside the material boundary such that the value of engagement of the milling cutter, when located at the starting point is substantially equal to the predetermined value of engagement;
- defining a location for each of one or more successive points such that the value of engagement of the milling cutter, when located at each one of the one or more points, is substantially equal to the predetermined value of engagement;
- and
- arranging the one or more passes to traverse the starting point and each of the one or more successive points to form the tool path, wherein defining the location of each of the one or more successive points comprises the steps of:
- projecting a first straight line from a preceding point, the first line being at a first angle with respect to the attitude of the tool path at the preceding point;
- projecting a second straight line from the preceding point, the second line being at a second angle with respect to a leading edge of the engagement angle of the milling cutter, the second angle being equal to one-half the first angle;
- determining an intersection of the second straight line projection and the in-process material boundary;
- and
- determining an intersection of a straight line having a length equal to a radius of the milling cutter and originating at the intersection of the second straight line with the in-process material boundary with the first line.
11 more elements
A method for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including of one or more passes, the method comprising the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the at least one tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes,
- wherein the milling cutter, traversing a first pass forms a second in-process material boundary adjacent to a part boundary or a first in-process material boundary such that an engagement of the milling cutter, traversing a second pass offset from the part boundary or from the first in-process material boundary by a radius of the milling cutter does not deviate by more than a predetermined amount from the predetermined value of the engagement,
- wherein a method for generating the first pass comprises the steps of:
- selecting a plurality of first points along the part boundary or the first in-process material boundary;
- determining a plurality of second points, each second point being located:
- (1) at a distance from a corresponding first point, and
- (2) at an angle of (pi-E)/2 from a normal to the parts boundary or the first in-process material boundary at the corresponding first point, B being the predetermined value of engagement angle;
- and
- generating the first pass as a smooth curve which intersects a plurality of third points, wherein each of the third points is offset from a corresponding one of the second points by the radius of the cutter and is on a line which is perpendicular to a smooth curve at a point which passes through each corresponding second point.
9 more elements
A method for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including one or more passes, the method comprising the steps of:
- creating a family of concentric indexed circles at each of two or more separate and distinct selected points within the region;
- connecting together the circles of adjacent families of circles having an identical index to form isoloops;
- generating the tool path by blending between the isoloops, and
- outputting instructions for controlling the milling cutter in accordance with the tool path.
1 more element
A method for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including of one or more passes, the method comprising the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the at least one tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes, wherein the region is bounded by inner and outer concentric circular boundaries, the method for generating the tool path comprising the steps of:
- defining a first set of passes, the first set of passes being semicircles, each one of the semicircles having a center at a center of the inner and the outer concentric circular boundaries;
- and
- a second set of passes, the second set of passes being semicircles, each one of the semicircles having a center offset from the center of the concentric circular boundaries by a predetermined amount, wherein an amount of the offset and a radius of each one of the semicircles in the second set of passes and a radius of each one of the semicircles in the first set of passes is based on the predetermined value of engagement, and wherein the first set of passes and the second set of passes are joined in an alternating tangent continuous fashion to form a generally spiral tool path for removing material between the inner boundary and the outer boundary.
4 more elements
An article of manufacture comprising a computer readable medium having stored thereon computer executable instructions for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including one or more passes, the instructions performing the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes,
- wherein the region is circular and wherein the one or more passes comprise a plurality of concentric circles, and wherein a radius of each one of the concentric circles is determined such that an engagement of the milling cutter milling each one of the concentric circles is substantially equal to the predetermined value of engagement, further including the steps of:
- (a) defining a largest one of the concentric circles on a first boundary;
- (b) determining if a smallest one of the concentric circles coincides with a second boundary;
- and
- (c) if the smallest concentric circle does not coincide with the second boundary within a predetermined value of engagement selecting an engagement for determining the radius of each one of the concentric circles which is incrementally smaller than the predetermined value of engagement and repeating steps b and c until the smallest concentric circle coincides with the second boundary within the predetermined value.
6 more elements
An article of manufacture comprising a computer readable medium having stored thereon computer executable instructions for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including one or more passes, the instructions performing the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes, the region having first, second and third sides, the first side being a current in-process material boundary and the second and third sides being non-parallel part or material boundaries, the first side meeting at its respective ends, the second and the third sides, and wherein each one of the one or more passes successively advances into the region, the instructions for computing the shape of at least one of the one or more passes comprising:
- determining a radius of curvature and a center of the current in-process material boundary;
- and
- determining a radius of curvature and a center for each one of the advancing passes based on the radius of curvature and the center of the current in-process material boundary, a half angle representative of the intersection of tangents to the second and the third sides and the predetermined value of engagement.
4 more elements
An article of manufacture comprising a computer readable medium having stored thereon computer executable instructions for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including one or more passes, the instructions performing the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the at least one tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes wherein the region has first, second and third sides, the first side being a current in-process material boundary and the second and third sides being parallel part or material boundaries, the first side meeting at its respective ends, the second and the third sides, and wherein each one of the one or more passes successively advances into the region, the method for computing the shape of at least one of the one or more passes comprising:
- determining a radius of curvature and a center of the current in-process material boundary;
- and
- determining a radius of curvature and a center for each one of the advancing passes based on only the radius of curvature and the center of the current in-process material boundary, the size of the milling cutter and the predetermined value of engagement.
4 more elements
An article of manufacture comprising a computer readable medium having stored thereon computer executable instructions for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including one or more passes, the instructions performing the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes,
- wherein the tool path is perpendicular to the rotational axis of the milling cutter and enters the workpiece from outside a material boundary at a predetermined attitude, the instructions further including the steps of:
- defining a location of a starting point outside the material boundary such that the value of engagement of the milling cutter, when located at the starting point is substantially equal to the predetermined value of engagement;
- defining a location for each of one or more successive points such that the value of engagement of the milling cutter, when located at each one of the one or more points, is substantially equal to the predetermined value of engagement;
- and
- arranging the one or more passes to traverse the starting point and each of the one or more successive points to form the tool path, wherein defining the location of each of the one or more successive points comprises by the steps of:
- projecting a first straight line from a preceding point, the first line being at a first angle with respect to the attitude of the tool path at the preceding point;
- projecting a second straight line from the preceding point, the second line being at a second angle with respect to a leading edge of the engagement angle of the milling cutter, the second angle being equal to one-half the first angle;
- determining an intersection of the second straight line projection with the in-process material boundary;
- and
- determining an intersection of a straight line having a length equal to a radius of the milling cutter and originating at the intersection of the second straight line with the in-process material boundary with the first line.
11 more elements
An article of manufacture comprising a computer readable medium having stored thereon computer executable instructions for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including one or more passes, the instructions performing the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes,
- wherein the milling cutter, traversing a first pass forms a second in-process material boundary adjacent to a part boundary or a first in-process material boundary such that the engagement of the milling cutter, traversing a second pass offset from the part boundary or from the first in-process material boundary by a radius of the milling cutter does not deviate by more than a predetermined amount from a predetermined value of the engagement
- wherein a method for generating the first pass comprises the steps of:
- selecting a plurality of first points along the part boundary or the first in-process material boundary;
- determining a plurality of second points, each second point being located:
- (1) at a distance from a corresponding first point, and
- (2) at an angle of (pi-E)/2 from a normal to the parts boundary or the first in-process material boundary at the corresponding first point, E being the predetermined value of engagement angle;
- and
- generating the first pass as a smooth curve which intersects a plurality of third points, wherein each of which third points is offset from a corresponding one of the second points by the radius of the cutter and is on a line which is perpendicular to a smooth curve which passes through each corresponding second point.
9 more elements
An article of manufacture comprising a computer readable medium having stored thereon computer executable instructions for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including one or more passes, the instructions performing the steps of:
- creating a family of concentric indexed circles at each of two or more separate and distinct selected points within the region;
- connecting together the circles of adjacent families of circles having an identical index to form isoloops;
- generating the tool path by blending between the isoloops, and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with the tool path.
1 more element
An article of manufacture comprising a computer readable medium having stored thereon computer executable instructions for generating a tool path for milling a region of a workpiece by a single milling cutter, the tool path including one or more passes, the instructions performing the steps of:
- storing a parameter from which a predetermined value of cutter engagement is determined;
- using a size of the milling cutter and the predetermined value of engagement to compute a shape of at least one of the one or more passes such that an engagement of the milling cutter traversing the tool path is controlled over the tool pass;
- and
- outputting instructions for controlling the milling cutter to mill the workpiece in accordance with each one of the one or more passes, wherein the region is bounded by inner and outer concentric circular boundaries, the instructions for generating the tool path comprising the steps of:
- defining a first set of passes, the first set of passes being semicircles, each one of the semicircles having a center at a center of the inner and the outer concentric circular boundaries;
- and
- a second set of passes, the second set of passes being semicircles, each one of the semicircles having a center offset from the center of the concentric circular boundaries by a predetermined amount, wherein an amount of the offset and a radius of each one of the semicircles in the second set of passes and a radius of each one of the semicircles in the first set of passes is based on the predetermined value of engagement, and wherein the first set of passes and the second set of passes are joined in an alternating tangent continuous fashion to form a generally spiral tool path for removing material between the inner boundary and the outer boundary.
4 more elements
Dependencies are inferred from the claim text.