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US4764878A Expired / Lapsed US ⏱️ 0.0 years remaining

Surface cutting method

Assignee: Fanuc Corp
•
Filing: 1986-07-21
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Granted: 1988-08-16
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Expires: 2006-07-21
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Abstract

Abstract The invention relates to a surface cutting method for back-and-forth surface cutting of the interior of an area (AR) bounded by a closed curve. The surface cutting method includes repeating the following steps: a step of obtaining points of intersection P i , Q i between an i-th cutting path (PT i ) and an offset curve offset (OFC') by (T+C+R) to the outer side of the closed curve, as well as points of intersection P i+1 , Q i+1 between the offset curve and an (i+1)th cutting path (PT i+1 ), where T, C and R represent excess thickness, amount of clearance and tool radius, respectively; a step of obtaining a coordinate value, in the cutting path direction, of an outermost point R i on the offset curve (OFC') between the points of intersection Q i , Q i+1 , where Q i is a point of intersection on a cutting end point side of the i-th cutting path (PT i ) and Q i+1 is a point of intersection on a cutting starting point side of the (i+1)th cutting path (PT i+1 ); a step of performing surface cutting by moving a tool along the i-th cutting path until a coordinate value of the position of the tool in the cutting path direction coincides with the coordinate value of the point R i in the cutting path direction; and a step of moving the tool at a cutting velocity to the next (i+1)th cutting path (PT i+1 ) in a shift direction.

Inventors

  • 👤 Kunio Tanaka
  • 👤 Yasushi Onishi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 16:22
CPC Classifications
B; B23; B23Q; B23Q15/00; G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/41; G05B2219/00; G05B2219/30; G05B2219/49; G05B2219/49381

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 294 words
A surface cutting method for cutting a surface within an area bounded by a predetermined closed curve by moving a tool along a cutting path PT i in a predetermined direction to cut the surface within the area, thenceforth moving the tool along an adjacent cutting path PT i+1 , obtained by a shift of a predetermined amount, in a direction opposite said predetermined direction to cut the surface, and repeating this back-and-forth cutting, said method characterized by including: a first step of obtaining points of intersection P i , Q i between said cutting path PT i and an offset curve offset by (T+C+R) to the outer side of said closed curve, as well as points of intersection P i+1 , Q i+1 between said offset curve and cutting path PT i+1 , where T, C and R represent excess thickness, amount of clearance and tool radius, respectively; a second step of obtaining a coordinate value, in the cutting path direction, of an outermost point R i on the offset curve between the points of intersection Q i , Q i+1 , where Q i is a point of intersection on a cutting end point side of the cutting path PT i and Q i+1 is a point of intersection on a cutting starting point side of the cutting path PT i+1 ; a third step of performing surface cutting by moving the tool along the cutting path PT i until a coordinate value of the position of the tool in the cutting path direction coincides with the coordinate value of said point R i in the cutting path direction; and a fourth step of moving the tool at a cutting velocity to the next cutting path PT i+1 in a shift direction.
Claim 2
Dependent Claim 294 words
A surface cutting method for cutting a surface within an area bounded by a predetermined closed curve by moving a tool along a cutting path PT i in a predetermined direction to cut the surface within the area, thenceforth moving the tool along an adjacent cutting path PT i+1 , obtained by a shift of a predetermined amount, in a direction opposite said predetermined direction to cut the surface, and repeating this back-and-forth cutting, said method characterized by including: a first step of obtaining points of intersection P i , Q i between said cutting path PT i and an offset curve offset by (T+C+R) to the outer side of said closed curve, as well as points of intersection P i+1 , Q i+1 between said offset curve and cutting path PT i+1 , where T, C and R represent excess thickness, amount of clearance and tool radius, respectively; a second step of obtaining a coordinate value, in the cutting path direction, of an outermost point R i on the offset curve between the points of intersection Q i , Q i+1 , where Q i is a point of intersection on a cutting end point side of the cutting path PT i and Q i+1 is a point of intersection on a cutting starting point side of the cutting path PT i+1 ; a third step of performing surface cutting by moving the tool along the cutting path PT i until a coordinate value of the position of the tool in the cutting path direction coincides with the coordinate value of said point R i in the cutting path direction; and a fourth step of moving the tool at a cutting velocity to the next cutting path PT i+1 in a shift direction.
Claim 3
Dependent Claim 26 words
A surface cutting method according to claim 1, wherein surface cutting is applied to the entirety of the area by repeating said first through fourth steps.
Claim 4
Dependent Claim 135 words
A surface cutting method according to claim 1, characterized in that said first step includes: a step of obtaining a position Y of the i-th cutting path in the shift direction in accordance with the following equation: Y=Y.sub.0 +W-i·P+R.sub.e where W represents the width, in said shift direction, of an area bounded by an offset curve offset by (T+C) to the outer side of said closed curve, Y 0 represents a position at the lowermost end of said area in the shift direction, P represents cut-in pitch, and R e represents effective tool radius, and said points of intersection P i , Q i are obtained by using data indicative of the position of said cutting path and data indicative of the offset curve offset by (T+C+R) to the outer side of the closed curve.

References Cited (Backward Citations)

US4621959A Cited
US4706200A Cited
US4706201A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-08-16 1992-02-15 1992-08-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-08-16 1996-02-15 1996-08-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-08-16 2000-02-15 2000-08-16 $7700.00 Window Closed / Lapsed

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