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US 4,286,880 AGranted
Scanning light beam lumber defect position system and method of using same
AssigneeThe Bendix Corporation
InventorAllen E. Young
Life of this patent
Estimating the term…
Abstract
In a lumber inspection and optimization system, an electro-optical defect position scanner is combined with a voice recognition device to enable a human inspector to locate and classify flaws on the surface of a board. The human inspector, by means of an indicator, pierces a light curtain to electro-optically locate a flaw. The indicator can be used to enhance the flaw by physically marking the board. With voice recognition, the human inspector can vocally classify the flaw. These voice classifications are later correlated with flaw information and used to process the board into its finished products.
Claims22
A system for detecting the positions of defects on at least one surface of a board of lumber comprising:
- conveyor means for moving the board in a predetermined direction at a predetermined speed;
- defect scanning means disposed along the conveyor means for generating a light curtain, having a moving light scan scanning at a predetermined frequency in a direction parallel to the predetermined direction and disposed slightly above and generally parallel to one surface of the board;
- encoder means for measuring the distance of the leading edge of the board past a predetermined point within the light curtain and for generating board leading edge position signals representative thereof;
- detector means, responsive to the interruption of the light curtain by an indicator indicating the leading edge of a particular defect on the moving board, for generating a position signal representative of the position of the leading edge of the defect within the light curtain and responsive to the removal of the indicator from the light curtain indicating the trailing edge of the defect on the moving board for generating position signals representative of the position of the trailing edge of the defect within the light curtain and;
- defect storage means for combining the board leading edge position signal, the defect leading edge and trailing edge position signals to generate defect position information in a defect data buffer containing signals representative of the positions of the leading edge and trailing edge of each particular defect on the board in usable coordinates.
2 more elements
A system for locating the position of particular defects disposed on a surface of a material, the system comprising:
- defect scanning means for generating a light curtain at a predetermined frequency, said light curtain having an incident moving light beam and a reflected light beam projected across a dimension of a region and scanning through said region in one direction which is generally perpendicular to said dimension;
- conveyor means for moving the material through said region in a direction generally perpendicular to said dimension and where said conveyor means maintains said material proximate to and below said moving light beam;
- detector means responsive to the interruption of said moving light beam during any particular scan for generating a first signal determination of the location of said interruption of said moving light beam within said region and for generating a second signal indicative of the location of the removal of the interruption within said region and where said first signal is determinative of the position of the leading edge a particular defect on said moving material within said region and where said second signal is determinative of the position of the trailing edge of said particular defect within said region.
A scanning system for detecting the positions of defects disposed on a surface of a material which has a known location with respect to the apparatus, the aparatus comprising:
- defect scanning means for generating a light scan at a predetermined frequency in one direction across a region adjacent the surface of the material;
- detector means responsive during one scan to an interruption, designating a starting position of a defect, of the light in the region for generating a first signal indicative of the position in said one direction of the interruption in the region and responsive during a subsequent scan to a removal, designating an end position of the defect, of the interruption from the region for generating a second signal indicative of the position in said one direction of the removal of the interruption from the region.
A position detection system comprising:
- a source of radiation;
- a scanner for successively scanning the radiation across a predetermined region;
- a detector circuit for detecting the radiation as the radiation is scanned across the region and responsive to the absence of interruption of the radiation as the radiation is scanned to generate a first output signal and to an interruption in the radiation in the scan to generate a second output signal, (RS);
- and
- circuit means coupled to said detector circuit and to said scanner for monitoring the instantaneous position of the radiation in the region as the radiation is scanned and thereacross, said circuit means responsive to said second output signal transmitted during one scan for transmitting electrical signals representative of the position of the interruption in the region during said one scan and to the first occurrence of the presence of said first output signal transmitted from said detector circuit during an entire subsequent scan for transmitting electrical signals representative of the position of the interruption in the region during the last preceding scan.
2 more elements
A defect position scanning apparatus comprising:
- a parabolic reflector having a reflective surface thereon and having an aperture located at the mid-point of said parabolic reflector;
- retro-reflector means disposed apart from and opposite to said reflective surface;
- a multi-sided rotating mirror proximate to and rotable about the focal point of said parabolic reflector;
- a first mirror located apart from said parabolic reflector oppositely situated from said rotating mirror;
- a source of radiation producing an incident light beam focused upon said first mirror and reflected by said first mirror through the aperture of said parabolic reflector onto said rotating mirror;
- and
- a second mirror having a second aperture therein, said second mirror disposed between said source of radiation and said first mirror and oriented relative to said incident beam so that said incident beam is directed through the second aperture and where said above recited components cooperate so that said incident light beam is directed through said second aperture onto said first mirror wherein said incident light beam is reflected through said first aperture onto a surface of said multi-sided mirror, said multi-sided mirror causing said incident beam to impinge upon various portions of said reflecting surface of said parabolic reflector as determined by the degree of rotation of said rotating mirror and then upon said retro-reflector, and retro-reflector thereupon reflecting said incident beam back to said parabolic reflector then to said multi-sided mirror through said first aperture onto said first mirror and then onto said second mirror.
4 more elements
A method of locating defects on the surface of a material, the steps comprising:
- 19.1 moving the material in a predetermined direction at a predetermined speed below a moving light curtain;
- 19.2 generating a light curtain of a determinable length comprising a moving light beam scanning between said determinable length at a predetermined frequency;
- 19.3 interrupting said moving light beam by inserting an indicator at a location within said light curtain corresponding to the leading edge of a particular defect on said moving board;
- 19.4 generating a defect leading edge signal or start of mark signal for each defect in response to the first interruption of said moving light beam in accordance with step 19.3;
- 19.5 permitting said moving light beam to return to its uninterrupted state by removing the indicator from said light curtain at a location within the light curtain corresponding to the location of the trailing edge of the particular defect on the moving board;
- 19.6 generating a defect trailing edge or end of mark signal in response to the return of the moving light beam to its interrupted state;
- 19.7 generating a signal indicative of the position of the leading edge of the board relative to a determinable location along said predetermined direction.
4 more elements
A method of locating defects on the surface of a material and of enhancing the defects so located by introducing defect class of quality, the steps comprising:
- 21.1 moving the material in a predetermined direction at a predetermined speed below a moving light curtain;
- 21.2 generating a light curtain of a determinable length comprising a moving light beam scanning between said determinable length at a predetermined frequency;
- 21.3 interrupting said moving light beam by inserting an indicator at a location within said light curtain corresponding to the leading edge of a particular defect on said moving board;
- 21.4 generating a defect leading edge signal or start of mark signal for each defect in response to the first interruption of said moving light beam in accordance with step 21.3;
- 21.5 permitting said moving light beam to return to its uninterrupted state by removing the indicator from said light curtain at a location with the light curtain corresponding to the location of the trailing edge of the particular defect on the moving board;
- 21.6 generating a defect trailing edge or end of mark signal in response to the return of the moving light beam to its uninterrupted state;
- 21.7 generating a signal indicative of the position of the leading edge of the board relative to a determinable location along said predetermined direction.
- 21.8 combining said leading edge signal with said defect leading edge signal and said defect trailing edge signal to obtain defect coordinate data relative to the leading edge of the board;
- 21. 9 generating vocal defect classification data in a relatively contiguous time frame with the generation of said defect leading edge signal;
- 21.10 combining said vocal defect classification data with said data as generated in Step 21.8.
7 more elements
Dependencies are inferred from the claim text.