US3839800A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for precisely contouring a work-piece imprecisely positioned on a fixture
Assignee: International Business Machines Corp
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Filing: 1971-04-20
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Granted: 1974-10-08
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Expires: 1991-04-20
Abstract
Abstract Method and apparatus for manufacturing precisely dimensioned metal parts on a program-controlled machine tool having a workpiece-supporting fixture, without the necessity of precisely locating the workpiece on the fixture. The workpiece is first placed on the fixture in an approximate position within predetermined limits of a standard position. The actual position (i.e., location and orientation) of the workpiece on the fixture is then measured by means of a programmed measuring apparatus while the fixture is accurately located with respect to that apparatus. The machine tool is controlled by a standard program, based on a standard position of the workpiece on its fixture and an accurate location of the fixture on the machine tool. The data defining the actual position of the workpiece on the fixture are utilized to modify the program of the machine tool, so as to compensate for the difference between the standard position of the workpiece and its actual position. The measurement of the workpiece position is performed at a measuring station, and the fixture with the workpiece mounted thereon is then conveyed to a fabrication station, which is shown as including a numerically-controlled five-axis machine tool. The position defining data determined at the measuring station is associated with identifying data of the particular fixture and is stored in a memory. When that fixture arrives at the fabrication station, it is accurately located with respect to the machine tool, and is identified. The identifying data is used to retrieve from the memory the proper set of position defining data, which is used to modify the machine tool program to produce the desired precisely dimensioned product.
Inventors
- 👤 S Bederman
- 👤 L Lankford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 05:04
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G01; G01B; G01B7/00; G01B7/004; G01B7/008; G05B19/408; G05B19/4083; G05B2219/00; G05B2219/30; G05B2219/36; G05B2219/36503; G05B2219/37; G05B2219/37193; G05B2219/37196
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
248 words
The method of detecting a plurality of discontinuities in surfaces of an object, oriented at random and determining the positional offset of the object from a predetermined position comprising the steps of: a. moving a probe towards a surface of an object until it engages the surface; b. moving the probe in the direction reverse to that used in step (a), for a predetermined distance from said object; c. stepping the probe at right angles to the path of movement toward and away from said object through a predetermined distance; d. moving the probe towards said object again until a second contact is made with said object; e. measuring the distance moved by the probe during step (d); f. repeating steps (b) through (e) a plurality of times and comparing the distances measured at each pair of successive steps (e) and calculating the general slope defined thereby; g. indicating a discontinuity if the the distance measured at one step (e) diverges from said slope more than a predetermined distance and storing data indicating the location of said discontinuity; h. repeating steps (a) through (g) again along a second path until an indication of a second discontinuity is obtained; i. employing means for calculating the orientation of said object relative to a predetermined set of coordinates, and the deviation of the locations of said discontinuities from predetermined positions relative to said previously recorded predetermined set of coordinates therefor, j. and providing an indication of the quantity of said deviation.
Claim 2
Independent Claim
248 words
The method of detecting a plurality of discontinuities in surfaces of an object, oriented at random and determining the positional offset of the object from a predetermined position comprising the steps of: a. moving a probe towards a surface of an object until it engages the surface; b. moving the probe in the direction reverse to that used in step (a), for a predetermined distance from said object; c. stepping the probe at right angles to the path of movement toward and away from said object through a predetermined distance; d. moving the probe towards said object again until a second contact is made with said object; e. measuring the distance moved by the probe during step (d); f. repeating steps (b) through (e) a plurality of times and comparing the distances measured at each pair of successive steps (e) and calculating the general slope defined thereby; g. indicating a discontinuity if the the distance measured at one step (e) diverges from said slope more than a predetermined distance and storing data indicating the location of said discontinuity; h. repeating steps (a) through (g) again along a second path until an indication of a second discontinuity is obtained; i. employing means for calculating the orientation of said object relative to a predetermined set of coordinates, and the deviation of the locations of said discontinuities from predetermined positions relative to said previously recorded predetermined set of coordinates therefor, j. and providing an indication of the quantity of said deviation.
Claim 3
Independent Claim
257 words
A method for measuring the slop of a surface with respect to a predetermined datum plane and detecting a discontinuity, comprising the steps of: a. moving a probe inwardly towards the surface in a direction at an angle to said datum plane until it contacts the surface; b. reversing the probe through a predetermined distance from its point of contact with the surface; c. stepping the probe laterally with respect to its previous path of movement through a predetermined distance; d. moving the probe inwardly toward the surface again until a second contact is made, said second movement being along a path substantially parallel to the First movement toward the surface in step (a); e. measuring the distance moved by the probe during the preceding step, and using such measurement as an indication of the average slope of the surface over the distance represented by the lateral step; f. repeatedly reversing the probe through a predetermined distance from its point of contact with the surface, then stepping the probe laterally along the direction in step (c) and moving the probe inwardly towards the surface again until contact is made along a path parallel to the movements in steps (a) and (d) and measuring the distance moved inwardly by the probe each time; g. employing calculating means adapted for determining slopes and detecting discontinuities from measured data and supplying said data thereto comprising said distances measured in (d) (a), (d), and (f) and h. producing from said calculating means data indicating the location of discontinuities in said surface.
Claim 4
Independent Claim
257 words
A method for measuring the slop of a surface with respect to a predetermined datum plane and detecting a discontinuity, comprising the steps of: a. moving a probe inwardly towards the surface in a direction at an angle to said datum plane until it contacts the surface; b. reversing the probe through a predetermined distance from its point of contact with the surface; c. stepping the probe laterally with respect to its previous path of movement through a predetermined distance; d. moving the probe inwardly toward the surface again until a second contact is made, said second movement being along a path substantially parallel to the First movement toward the surface in step (a); e. measuring the distance moved by the probe during the preceding step, and using such measurement as an indication of the average slope of the surface over the distance represented by the lateral step; f. repeatedly reversing the probe through a predetermined distance from its point of contact with the surface, then stepping the probe laterally along the direction in step (c) and moving the probe inwardly towards the surface again until contact is made along a path parallel to the movements in steps (a) and (d) and measuring the distance moved inwardly by the probe each time; g. employing calculating means adapted for determining slopes and detecting discontinuities from measured data and supplying said data thereto comprising said distances measured in (d) (a), (d), and (f) and h. producing from said calculating means data indicating the location of discontinuities in said surface.
Claim 5
Dependent Claim
192 words
Apparatus for measuring slopes of surfaces and a discontinuity therebetween on a workpiece, comprising: a. means for supporting the workpiece; b. 2 probe; c. means for supporting the probe for movement along a plurality of paths one at a time at an angle to said workpiece; d. program-controlled means for repeatedly moving the probe along said paths until it contacts the workpiece, reversing the probe so as to retrace its path for a predetermined distance, then moving the probe parallel to the plane through an additional predetermined distance and along an additional path moving the probe substantially parallel to its first path until it again contacts the workpiece and for shifting to another location and repeating said sequence of operations; and e. means for measuring the distance moved by the probe as it travels along each of said additional substantially parallel paths; f. calculating means for calculating slopes of planes and discontinuities between planes calculating means to receive data from said means for measuring said producing data indicating slopes and locations of discontinuities; g. and means for registering slopes of planes and the location of a discontinuity between a plurality of planes.
Claim 6
Dependent Claim
192 words
Apparatus for measuring slopes of surfaces and a discontinuity therebetween on a workpiece, comprising: a. means for supporting the workpiece; b. 2 probe; c. means for supporting the probe for movement along a plurality of paths one at a time at an angle to said workpiece; d. program-controlled means for repeatedly moving the probe along said paths until it contacts the workpiece, reversing the probe so as to retrace its path for a predetermined distance, then moving the probe parallel to the plane through an additional predetermined distance and along an additional path moving the probe substantially parallel to its first path until it again contacts the workpiece and for shifting to another location and repeating said sequence of operations; and e. means for measuring the distance moved by the probe as it travels along each of said additional substantially parallel paths; f. calculating means for calculating slopes of planes and discontinuities between planes calculating means to receive data from said means for measuring said producing data indicating slopes and locations of discontinuities; g. and means for registering slopes of planes and the location of a discontinuity between a plurality of planes.
Claim 7
Dependent Claim
237 words
Apparatus for detecting a discontinuity in the surface of a workpiece, comprising: a. a probe; b. means supporting the probe for movement along a first path which intersects a surface of the workpiece; c. program-controlled means for moving the probe along said path until it contacts the workpiece, reversing the movement of the probe so as to retrace the first path for a predetermined distance, then moving the probe at right angles to said path through a second predetermined distance and moving the probe along a second path parallel to said path until it again contacts the workpiece; d. means for measuring the distance moved by the probe as it travels along said second path; e. means for repeatedly and cyclically operating said program-controlled means and said distance measuring means; f. means for comparing successive measurements by said measuring means coupled to received data from said measuring means; g. means for calculating the slope defined by said successive measurements coupled to receive said measurements, h. means for computing an expected value of the address at any given location for a point on said slope coupled to said means for calculating; and i. means for indicating a discontinuity at a said location on the surface of the workpiece when the difference between a particular measurement by said measuring means and said expected value for said location is greater than a second predetermined distance coupled to receive said values.
Claim 8
Dependent Claim
237 words
Apparatus for detecting a discontinuity in the surface of a workpiece, comprising: a. a probe; b. means supporting the probe for movement along a first path which intersects a surface of the workpiece; c. program-controlled means for moving the probe along said path until it contacts the workpiece, reversing the movement of the probe so as to retrace the first path for a predetermined distance, then moving the probe at right angles to said path through a second predetermined distance and moving the probe along a second path parallel to said path until it again contacts the workpiece; d. means for measuring the distance moved by the probe as it travels along said second path; e. means for repeatedly and cyclically operating said program-controlled means and said distance measuring means; f. means for comparing successive measurements by said measuring means coupled to received data from said measuring means; g. means for calculating the slope defined by said successive measurements coupled to receive said measurements, h. means for computing an expected value of the address at any given location for a point on said slope coupled to said means for calculating; and i. means for indicating a discontinuity at a said location on the surface of the workpiece when the difference between a particular measurement by said measuring means and said expected value for said location is greater than a second predetermined distance coupled to receive said values.
Claim 9
Dependent Claim
251 words
Apparatus for measuring the slope of a surface of an object with respect to a predetermined datum plane, comprising: a. first means for moving a probe towards the surface in a direction at right angles to said datum plane until it contacts the surface; b. second means for reversinG the probe through a predetermined distance from its point of contact with the surface; c. third means for stepping said probe laterally at right angles to its previous path of movement through a predetermined distance; d. fourth means for moving said probe toward the surface again until a repeated contact is made, said movement towards said repeated contact being along a path substantially parallel to the first movement toward the surface; e. fifth means for measuring the distance moved by said probe during operation of said fourth means; f. means for controlling said second, third and fourth means to perform their operations after said first means repeatedly, and g. calculating means for calculating slopes using such measurement by said fifth means as an indication of the average slope of the surface over the distance represented by the lateral step having an input coupled to the output of said fifth means, h. said discontinuity calculating means including means for determining a discontinuity at a point on data contour of said object with respect to a slope calculated by said slope calculating means by detecting a predetermined deviation of a measurement at such point from the value near such point of said average slope.
Claim 10
Dependent Claim
251 words
Apparatus for measuring the slope of a surface of an object with respect to a predetermined datum plane, comprising: a. first means for moving a probe towards the surface in a direction at right angles to said datum plane until it contacts the surface; b. second means for reversinG the probe through a predetermined distance from its point of contact with the surface; c. third means for stepping said probe laterally at right angles to its previous path of movement through a predetermined distance; d. fourth means for moving said probe toward the surface again until a repeated contact is made, said movement towards said repeated contact being along a path substantially parallel to the first movement toward the surface; e. fifth means for measuring the distance moved by said probe during operation of said fourth means; f. means for controlling said second, third and fourth means to perform their operations after said first means repeatedly, and g. calculating means for calculating slopes using such measurement by said fifth means as an indication of the average slope of the surface over the distance represented by the lateral step having an input coupled to the output of said fifth means, h. said discontinuity calculating means including means for determining a discontinuity at a point on data contour of said object with respect to a slope calculated by said slope calculating means by detecting a predetermined deviation of a measurement at such point from the value near such point of said average slope.
Claim 11
Dependent Claim
191 words
Apparatus in accordance with claim 3 wherein said object includes a plurality of discontinuities, said object including datum contours including two straight, non-parallel lines each comprising the intersection of a pair of planes of any form having a straight intersection for facilitating determination of orientation of a predetermined object, said first means for calculating employing said probe for searching for datum contours comprising coordinates of at least two points Q, R and S, T respectively for each of said datum contours, said calculating means being then operative for computing actual position defining data, accepting said coordinates, calculating direction cosines of said lines, testing for intersection of said datum contours and finding said position defining data and storing said actual position defining data, said calculating means fetching standard direction cosines and standard position data, and then computing and storing matrices and subsequently employing said matrices and fetching stored actual position defining data to determine the error trigonometrically and algebraically between said actual position data and said standard position data in three dimensions including computation of tilt, rotation, and linear displacement of said object from the position defined by said standard position data.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-07 | 1978-04-08 | 1978-10-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-07 | 1982-04-08 | 1982-10-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-07 | 1986-04-08 | 1986-10-08 | $7700.00 | Window Closed / Lapsed |