Optical triangulation gear inspection

Claim 3

A method according to claim 1 further comprising automatically controlling steps (b) through (h).

Claim 4

A method according to claim 2 wherein said controlling step comprises: entering the type of gear; determining, from the entered gear type, correct inspection positions for said light source and light detector relative to a gear located in said inspection position; and automatically positioning said light source and light detector at said correct inspection positions relative to said gear.

Claim 5

A method according to claim 1 wherein said light source and light detector are provided in a unitary housing.

Claim 6

A method according to claim 1 wherein said light detector comprises an image scanning light detector array, said array having an integrating time long than the array scan time.

Claim 7

A method according to claim 1 wherein said gear geometry determining step comprises: obtaining a series of data points representative of locations of said surface; fitting a curve to a series of said data points; and comparing said curve to the correct shape of said surface.

Claim 8

A method according to claim 1 further comprising lens means for imaging said zone of light onto said detector, and wherein said light detector is canted at an angle, not 90°, to the optical axis of said lens, said cant angle being chosen so as to vary the magnification on the detector as a function of the width of the projected light zone on said surface.

Claim 9

A method according to claim 1 wherein the light is projected in a direction which is offset, when viewed along the gear axis, from a line normal to the gear surface at the zone of projected light.

Claim 10

A method according to claim 8 wherein light is directed in a direction which is offset from said normal line by an angle of up to 45°.

Claim 11

A method according to claim 1 wherein the light is projected in a line which, when viewed along the gear axis, is parallel to a gear radius and spaced therefrom by 0.1 to 0.75 times the gear pitch diameter.

Claim 12

A method according to claim 1 wherein the light is projected in a line inclined to a plane perpendicular to the gear axis.

Claim 13

A method according to claim 1 wherein the zone of light is a spot having a diameter of up to 0.3 mm.

Claim 14

A method according to claim 1 wherein said light source comprises a pulsed laser.

Claim 15

A method according to claim 13 wherein said gear is mounted in a grinding machine.

Claim 16

Apparatus for determining gear geometry comprising: (a) means for positioning a gear in an inspection position, said gear having a gear axis; (b) a light source for projecting a zone of light onto a surface of a gear at a first surface location, said light being projected onto said surface in a direction which is offset from a gear radius when viewed along the gear axis; (c) a light detector for detecting an image of said zone of light; (d) means for determining the position of a detected image of said zone of light; (e) means for determining from the determined image position, the location of the gear surface on which said zone of light was projected; (f) means for moving said gear relative to said light source such that said light source is positioned to project a zond of light onto said gear surface at a second surface location different from said first surface location; (g) means for repeating steps (b) through (f); and (h) means for determining, from a plurality of determinations of the location of the gear surface on which said zone of light was projected, geometry of said gear.

Claim 17

Apparatus for determining gear geometry comprising: (a) means for positioning a gear in an inspection position, said gear having a gear axis; (b) a light source for projecting a zone of light onto a surface of a gear at a first surface location, said light being projected onto said surface in a direction which is offset from a gear radius when viewed along the gear axis; (c) a light detector for detecting an image of said zone of light; (d) means for determining the position of a detected image of said zone of light; (e) means for determining from the determined image position, the location of the gear surface on which said zone of light was projected; (f) means for moving said gear relative to said light source such that said light source is positioned to project a zond of light onto said gear surface at a second surface location different from said first surface location; (g) means for repeating steps (b) through (f); and (h) means for determining, from a plurality of determinations of the location of the gear surface on which said zone of light was projected, geometry of said gear.

Claim 18

Apparatus according to claim 15 further comprising means for automatically controlling means (b) through (h).

Claim 19

Apparatus according to claim 16 wherein said controlling means comprises: means for entering the type of gear; means for determining, from the entered gear type, correct inspection positions for said light source and light detector relative to a gear located in said inspection position; and means for automatically positioning said light source and light detector at said correct inspection positions relative to said gear.

Claim 20

Apparatus according to claim 15 wherein said light source and light detector are provided in a unitary housing.

Claim 21

Apparatus according to claim 15 wherein said light detector comprises an image scanning light detector array, said array having an integrating time longer than the array scan time.

Claim 22

Apparatus according to claim 15 wherein said gear geometry determining means comprises: means for obtaining a series of data points representative of locations of said surface; means for fitting a curve to a series of said data points; and means for comparing said curve to the correct shape of said surface.

Claim 23

Apparatus according to claim 15 further comprising lens means for imaging said zone of light onto said detector, and wherein said light detector is canted at an angle, not 90°, to the optical axis of said lens, said cant angle being chosen so as to vary the magnification on the detector as a function of the width of the projected light zone on said surface.

Claim 24

Apparatus according to claim 15 wherein the light is projected in a direction which is offset, when viewed along the gear axis, from a line normal to the gear surface at the zone of projected light.

Claim 25

Apparatus according to claim 22 wherein light is directed in a direction which is offset from said normal line by an angle of up to 45°.

Claim 26

Apparatus according to claim 15 wherein the light is projected in a line which, when viewed along the gear axis, is parallel to a gear radius and spaced therefrom by 0.1 to 0.75 times the gear pitch diameter.

Claim 27

Apparatus according to claim 15 wherein the light is projected in a line inclined to a plane perpendicular to the gear axis.

Claim 28

Apparatus according to claim 15 wherein the zone of light is a spot having a diameter of up to 0.3 mm.

Claim 29

Apparatus according to claim 15 wherein said light source comprises a pulsed laser.

Claim 30

Apparatus according to claim 27 wherein said gear is mounted in a grinding machine.