US4852029A
Expired / Lapsed
US
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Automated material classification apparatus and method
Assignee: CLARY LUMBER COMPANY Inc A NORTH CAROLINA Corp
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Filing: 1987-06-17
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Granted: 1989-07-25
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Expires: 2007-06-17
Abstract
Abstract An automated method and apparatus for grading pre-cut lumber products according to selected physical properties thereof such as modulus of elasticity (MOE) and modulus of rupture (MOR) are disclosed. A conveyor transports boards to be graded to an automated lumber feeding mechanism which sequentially rotates each board from a loading to a grading position. In the grading position, an impactor impacts one longitudinal end of the board to generate a compression force and a detector at the opposite longitudinal end converts the compression force to an electrical signal. Data acquisition circuitry samples and stores at least one cycle of the signal and a computer analyzes the samples and assigns values to predetermined parameters which characterize the signal. The computer utilizes the parameter values in one or more predetermined formulas which are optimum statistical predictors of the selected physical properties as a function of the parameters to obtain values for the selected physical parameters. The computer assigns a grade classification to each board according to the grading criteria based upon the calculated values of the physical parameters and a marking mechanism applies appropriate grade indicia to the board.
Inventors
- 👤 Thomas A. Pope, deceased
- 👤 Walter B. Wallin
- 👤 Mitchell R. Cutrell
- 👤 James J. Melton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 07:26
CPC Classifications
G; G01; G01N; G01N3/00; G01N3/20; G01N33/00; G01N33/46
Claims Analysis
Total Claims: 71
Claim 1
Independent Claim
231 words
Automated material classification apparatus for material having a first end and a second end, said apparatus comprising: detector means for sensing an impact force and for providing a signal in response to the impact force; means for slidably support:ing the material so that the material is freely movable relative to said detector means in one direction; impactor means, located substantially at the first end of the material, for generating a force in the material in the one direction by impacting the material; means locating said detector means substantially at the second end of the material, and generally opposite the first end of the material in the one direction, so that the detector means senses said impactor means force transmitted through the material and provides a signal related to said force; computing means for assigning values to a selected plurality of predetermined parametrs characterizing said signal for at least one cycle thereof; said computing means including means for processing said selected predetermined parameters according to at least one predetermined formula relating said parameters to at least one selected physical parameter of the material to generate at least one value signal corresponding to said at least one selected physical parameter; and identifying means for receiving said at least one value signal from said computing means and being operative to provide classification indicia associated with said at least one selected parameter of the material.
Claim 2
Dependent Claim
231 words
Automated material classification apparatus for material having a first end and a second end, said apparatus comprising: detector means for sensing an impact force and for providing a signal in response to the impact force; means for slidably support:ing the material so that the material is freely movable relative to said detector means in one direction; impactor means, located substantially at the first end of the material, for generating a force in the material in the one direction by impacting the material; means locating said detector means substantially at the second end of the material, and generally opposite the first end of the material in the one direction, so that the detector means senses said impactor means force transmitted through the material and provides a signal related to said force; computing means for assigning values to a selected plurality of predetermined parametrs characterizing said signal for at least one cycle thereof; said computing means including means for processing said selected predetermined parameters according to at least one predetermined formula relating said parameters to at least one selected physical parameter of the material to generate at least one value signal corresponding to said at least one selected physical parameter; and identifying means for receiving said at least one value signal from said computing means and being operative to provide classification indicia associated with said at least one selected parameter of the material.
Claim 3
Dependent Claim
24 words
The automated material classification apparatus defined in claim 1 wherein said identifying means includes marking means for applying said classification indicia to said material.
Claim 4
Dependent Claim
24 words
The auotmated material classification apparatus defined in claim 1 wherein said impactor means includes means for impacting said material with a selectable predetermined force.
Claim 5
Dependent Claim
37 words
The automated material classification apparatus defined in claim 1 wherein said impactor means includes: movable means for impacting said piece of material; and means for securely holding said piece of material in proximity to said movable means.
Claim 6
Dependent Claim
52 words
The automated material classification apparatus defined in claim 1 wherein said impactor means includes: impacting means for applying an impact force to generate said compression force; and transmitter means located intermediate said impacting means and said material for receiving said impact force from said impacting means and transmitting it to said material.
Claim 7
Dependent Claim
35 words
The automated material classification apparatus defined in claim 5 wherein said transmitter means included means for contacting said material, said means being adapted to minimize the plastic zone between said material and said transmitter means.
Claim 8
Dependent Claim
27 words
The automated material classification apparatus defined in claim 1 including storage means for storing said signal related to said compression force for use by said computing means.
Claim 9
Dependent Claim
42 words
The automated material classification apparatus defined in claim 7 wherein said storage means comprises: means for digitizing said signal at selected discrete time intervals to provide a plurality of digital words representing said signal; and memory means for storing said digital words.
Claim 10
Dependent Claim
33 words
The automated material classification apparatus defined in claim 1 wherein said computing means includes means connected to said impactor means for initiating operation of said impactor means in response to a predetermined condition.
Claim 11
Dependent Claim
43 words
The automated material classification apparatus defined in claim 9 wherein said means for initiating operation includes means responsive to the positioning of a piece of said material in a predetermined location proximal to said impactor means for initiating operation of said impactor means.
Claim 12
Dependent Claim
40 words
The automated material classification apparatus defined in claim 1 wherein said computing means includes means for selecting at least one said predetermined formula corresponding to a selected material from a plurality of predetermined formulas corresponding to a plurality of materials.
Claim 13
Dependent Claim
40 words
The automated material classification apparatus defined in claim 1 wherein said predetermined formula comprises an equation statistically derived from said predetermined parameters and said at least one selected physical parameter for a plurality of destructively tested pieces of said material.
Claim 14
Dependent Claim
33 words
The automated material classification apparatus defined in claim 12 wherein said equation is the statistically optimum predictor of the selected physical parameter of said material as a function of said selected predetermined parameters.
Claim 15
Dependent Claim
61 words
The automated material classification apparatus defined in claim 1 including means for supporting said material between said impactor means and said detector means, said impactor means being operative to impact a first surface of said material and said detector means being operative to provide a signal related to the compression force generated in said material at a second opposite surface thereof.
Claim 16
Dependent Claim
54 words
The automated material classification apparatus defined in claim 1 including material feeding means for automatically sequentially positioning individual pieces of said material between said impactor means and said detector means with a first surface of said material being adjacent to said impactor means and a second opposite surface being adjacent to said detector means.
Claim 17
Dependent Claim
70 words
The automated material classification apparatus defined in claim 15 wherein said material feeding means comprises: rotatable carousel means having a plurality of spaced material receiving slots for holding a plurality of pieces of said material; and drive means for rotating said carousel incrementally so that each slot rotates sequentially between a material loading position, a material classification position between said impactor and said detector means, and a material unloading position.
Claim 18
Independent Claim
222 words
A method of classifying a material having a first end and a second end, the method comprising the steps of: slidably supporting the material so that the material is freely movable relative to detector means in one direction; impacting a piece of the material with impacting means located substantially at the first end of the material, for generating a force in the material in the one direction by impacting the material; in response to said impacting, providing a signal related to said force from said detector means located substantially at the second end of the material, and generally opposite the first end of the material in the one direction, so that the detector means senses said impactor means force transmitted through the material and provides a signal related to said force; assigning values to a selected plurality of predetermined parameters characterizing said signal for at least one cycle thereof; processing said selected predetermined parameters according to at least one predetermined formula relating said parameters to at least one selected physical parameter of the material to generate at least one value signal corresponding to said at least one selected physical parameter; and providing said at least one value signal to identifying means to cause said means to provide a classification indicia associated with said at least one selected physical parameter of the material.
Claim 19
Independent Claim
222 words
A method of classifying a material having a first end and a second end, the method comprising the steps of: slidably supporting the material so that the material is freely movable relative to detector means in one direction; impacting a piece of the material with impacting means located substantially at the first end of the material, for generating a force in the material in the one direction by impacting the material; in response to said impacting, providing a signal related to said force from said detector means located substantially at the second end of the material, and generally opposite the first end of the material in the one direction, so that the detector means senses said impactor means force transmitted through the material and provides a signal related to said force; assigning values to a selected plurality of predetermined parameters characterizing said signal for at least one cycle thereof; processing said selected predetermined parameters according to at least one predetermined formula relating said parameters to at least one selected physical parameter of the material to generate at least one value signal corresponding to said at least one selected physical parameter; and providing said at least one value signal to identifying means to cause said means to provide a classification indicia associated with said at least one selected physical parameter of the material.
Claim 20
Dependent Claim
34 words
The method defined in claim 17 wherein the step of providing said at least one value signal to said identifying means includes causing said identifying means to apply said classification indicia to said material.
Claim 21
Dependent Claim
27 words
The method defined in claim 17 wherein the step of impacting a piece of said material includes impacting said piece of material with a selectable predetermined force.
Claim 22
Dependent Claim
41 words
The method defined in claim 17 wherein the step of impacting a piece of said material includes the steps of: securely holding said piece of material in proximity to movable means; and impacting said piece of material with said movable means.
Claim 23
Dependent Claim
19 words
The method defined in claim 17 including the step of storing said signal for use in assigning said values.
Claim 24
Dependent Claim
43 words
The method defined in claim 21 wherein the step of storing said signal includes the steps of: digitizing said signal at selected discrete time intervals to provide a plurality of digital words representing said signal; and storing said digital words in memory means.
Claim 25
Dependent Claim
27 words
The method defined in claim 17 wherein the step of impacting said piece of material includes impacting said piece of material in response to a predetermined condition.
Claim 26
Dependent Claim
26 words
The method defined in claim 23 wherein said predetermined condition comprises said piece of material being positioned in a predetermined location proximal to said impactor means.
Claim 27
Dependent Claim
34 words
The method defined in claim 17 including the step of selecting at least one said predetermined formula corresponding to a selected material from a plurality of predetermined formulas corresponding to a plurality of materials.
Claim 28
Dependent Claim
37 words
The method defined in claim 17 wherein said predetermined formula comprises an equation statistically derived from said predetermined parameters and said at least one selected physical parameter for a plurality of destructively tested pieces of said material.
Claim 29
Dependent Claim
33 words
The method defined in claim 26 wherein said equation defines the statistically optimum predictor of said at least one selected physical parameter of said material as a function of said selected predetermined parameters.
Claim 30
Dependent Claim
63 words
The method defined in claim 27 including the steps of: supporting said piece of material between said impacting means and said detecting means; and operating said impactor means to impact a first surface of said piece of material and said detector means to provide a signal related to the compression force generated in said piece of material at a second opposite surface thereof.
Claim 31
Dependent Claim
50 words
The method defined in claim 17 including the step of: automatically sequentially positioning individual pieces of said material between said impacting means and said detecting means with a first surface of said material being adjacent to said impacting means and a second opposite surface being adjacent to said detecting means.
Claim 32
Dependent Claim
237 words
Automated lumber classification apparatus comprising: detector means for sensing an impact force and for providing a signal in response to the impact force; means for slidably supporting a piece of lumber so that the piece of lumber is freely movable relative to said detector means in one direction; impactor means, located substantially at a first end of the piece of lumber, for generating a force in the piece of lumber in the one direction by impacting the lumber; means locating said detector means substantially at the second end of the piece of lumber, and generally opposite the first end of the piece of lumber in the one direction, so that the detector means senses said impactor means force transmitted through the piece of lumber and provides a signal related to said force; computing means for assigning values to a selected plurality of predetermined parametrs characterizing said signal for at least one cycle thereof; said computing means including means for processing said selected predetermined parameters according to at least one predetermined formula relating said parameters to at least one selected physical parameter of the piece of lumber to generate at least one value signal corresponding to said at least one selected physical parameter; and identifying means for receiving said at least one value signal from said computing means and being operative to provide classification indicia associated with said at least one selected parameter of the piece of lumber.
Claim 33
Dependent Claim
237 words
Automated lumber classification apparatus comprising: detector means for sensing an impact force and for providing a signal in response to the impact force; means for slidably supporting a piece of lumber so that the piece of lumber is freely movable relative to said detector means in one direction; impactor means, located substantially at a first end of the piece of lumber, for generating a force in the piece of lumber in the one direction by impacting the lumber; means locating said detector means substantially at the second end of the piece of lumber, and generally opposite the first end of the piece of lumber in the one direction, so that the detector means senses said impactor means force transmitted through the piece of lumber and provides a signal related to said force; computing means for assigning values to a selected plurality of predetermined parametrs characterizing said signal for at least one cycle thereof; said computing means including means for processing said selected predetermined parameters according to at least one predetermined formula relating said parameters to at least one selected physical parameter of the piece of lumber to generate at least one value signal corresponding to said at least one selected physical parameter; and identifying means for receiving said at least one value signal from said computing means and being operative to provide classification indicia associated with said at least one selected parameter of the piece of lumber.
Claim 34
Dependent Claim
24 words
The automated lumber classification apparatus defined in claim 30 wherein said identifying means includes marking means for applying said classification indicia to said lumber.
Claim 35
Dependent Claim
24 words
The automated lumber classification apparatus defined in claim 30 wherein said impactor means includes means for impacting said lumber with a selectable predetermined force.
Claim 36
Dependent Claim
37 words
The automated lumber classification apparatus defined in claim 30 wherein said impactor means includes: movable means for impacting said piece of lumber; and means for securely holding said piece of lumber in proximity to said movable means.
Claim 37
Dependent Claim
31 words
The automated lumber classification apparatus defined in claim 33 wherein said means for holding comprises means for holding said lumber longitudinally with an end thereof in proximity to said movable means.
Claim 38
Dependent Claim
52 words
The automated lumber classification apparatus defined in claim 30 wherein said impactor means includes: impacting means for applying an impact force to generate said compression force; and transmitter means located intermediate said impacting means and said lumber for receiving said impact force from said impacting means and transmitting it to said lumber.
Claim 39
Dependent Claim
35 words
The automated lumber classification apparatus defined in claim 35 wherein said transmitter means includes means for contacting said lumber, said means being adapted to minimize the plastic zone between said lumber and said transmitter means.
Claim 40
Dependent Claim
27 words
The automated lumber classification apparatus defined in claim 30 including storage means for storing said signal related to said compression force for use by said computing means.
Claim 41
Dependent Claim
42 words
The automated lumber classification apparatus defined in claim 33 wherein said storage means comprises: means for digitizing said signal at selected discrete time intervals to provide a plurality of digital words representing said signal; and memory means for storing said digital words.
Claim 42
Dependent Claim
33 words
The automated lumber classification apparatus defined in claim 30 wherein said computing means includes means connected to said impactor means for initiating operation of said impactor means in response to a predetermined condition.
Claim 43
Dependent Claim
43 words
The automated lumber classification apparatus defined in claim 39 wherein said means for initiating operation includes means responsive to the positioning of a piece of said lumber in a predetermined location proximal to said impactor means for initiating operation of said impactor means.
Claim 44
Dependent Claim
43 words
The automated lumber classification apparatus defined in claim 30 wherein said computing means includes means for selecting at least one said predetermined formula corresponding to a selected lumber type from a plurality of predetermined formulas corresponding to a plurality of selected lumber types.
Claim 45
Dependent Claim
40 words
The automated lumber classification apparatus defined in claim 30 wherein said predetermined formula comprises an equation statistically derived from said predetermined parameters and said at least one selected physical parameter for a plurality of destructively tested pieces of said lumber.
Claim 46
Dependent Claim
36 words
The automated lumber classification apparatus defined in claim 42 wherein said equation defines the statistically optimum predictor of said at least one selected physical parameter of said lumber as a function of said selected predetermined parameters.
Claim 47
Dependent Claim
61 words
The automated lumber classification apparatus defined in claim 30 including means for supporting said lumber between said impactor means and said detector means, said impactor means being operative to impact a first surface of said lumber and said detector means being operative to provide a signal related to the compression force generated in said lumber at a second opposite surface thereof.
Claim 48
Dependent Claim
45 words
The automated lumber classification apparatus defined in claim 44 wherein said means for supporting said lumber comprises means for supporting said lumber edgewise with a first longitudinal end thereof adjacent to said impactor means and a second opposite longitudinal end adjacent to said detector means.
Claim 49
Dependent Claim
54 words
The automated lumber classification apparatus defined in claim 30 including lumber feeding means for automatically sequentially positioning individual pieces of said lumber between said impactor means and said detector means with a first surface of said material being adjacent to said impactor means and a second opposite surface being adjacent to said detector means.
Claim 50
Dependent Claim
31 words
The automated lumber classification apparatus defined in claim 46 wherein said first surface comprises a first longitudinal end of said lumber and said second surface comprises a second opposite longitudinal end.
Claim 51
Dependent Claim
71 words
The automated lumber classification apparatus defined in claim 46 wherein said lumber feeding means comprises: rotatable carousel means having a plurality of spaced lumber receiving slots for holding a plurality of pieces of said lumber edge-wise; and drive means for rotating said carousel incrementally so that each slot rotates sequentially between a lumber loading position, a lumber classification position between said impactor and said detector means, and a lumber unloading position.
Claim 52
Independent Claim
236 words
A method of classifying lumber having a first end and a second end, the method comprising the steps of: slidably supporting the lumber so that the lumber is freely movable relative to detector means in one direction; impacting a piece of the lumber with impacting means located substantially at the first end of the piece of lumber, for generating a force in the piece of lumber in the one direction by impacting the piece of lumber; in response to said impacting, providing a signal related to said force from said detector means located substantially at the second end of the piece of lumber, and generally opposite the first end of the piece of lumber in the one direction, so that the detector means senses said impactor means force transmitted through the piece of lumber and provides a signal related to said force; assigning values to a selected plurality of predetermined parameters characterizing said signal for at least one cycle thereof; processing said selected predetermined parameters according to at least one predetermined formula relating said parameters to at least one selected physical parameter of the piece of lumber to generate at least one value signal signal for at least one selected physical parameter; and providing said at least one value signal to identifying means to cause said means to provide a classification indicia associated with said at least one selected physical parameter of the piece of lumber.
Claim 53
Independent Claim
236 words
A method of classifying lumber having a first end and a second end, the method comprising the steps of: slidably supporting the lumber so that the lumber is freely movable relative to detector means in one direction; impacting a piece of the lumber with impacting means located substantially at the first end of the piece of lumber, for generating a force in the piece of lumber in the one direction by impacting the piece of lumber; in response to said impacting, providing a signal related to said force from said detector means located substantially at the second end of the piece of lumber, and generally opposite the first end of the piece of lumber in the one direction, so that the detector means senses said impactor means force transmitted through the piece of lumber and provides a signal related to said force; assigning values to a selected plurality of predetermined parameters characterizing said signal for at least one cycle thereof; processing said selected predetermined parameters according to at least one predetermined formula relating said parameters to at least one selected physical parameter of the piece of lumber to generate at least one value signal signal for at least one selected physical parameter; and providing said at least one value signal to identifying means to cause said means to provide a classification indicia associated with said at least one selected physical parameter of the piece of lumber.
Claim 54
Dependent Claim
34 words
The method defined in claim 49 wherein the step of providing said at least one value signal to said identifying means includes causing said identifying means to apply said classification indicia to said lumber.
Claim 55
Dependent Claim
27 words
The method defined in claim 49 wherein the step of impacting a piece of said lumber includes impacting said piece of lumber with a selectable predetermined force.
Claim 56
Dependent Claim
41 words
The method defined in claim 49 wherein the step of impacting a piece of said lumber includes the steps of: securely holding said piece of lumber in proximity to movable means; and impacting said piece of lumber with said movable means.
Claim 57
Dependent Claim
19 words
The method defined in claim 49 including the step of storing said signal for use in assigning said values.
Claim 58
Dependent Claim
43 words
The method defined in claim 53 wherein the step of storing said signal includes the steps of: digitizing said signal at selected discrete time intervals to provide a plurality of digital words representing said signal; and storing said digital words in memory means.
Claim 59
Dependent Claim
27 words
The method defined in claim 49 wherein the step of impacting said piece of lumber includes impacting said piece of lumber in response to a predetermined condition.
Claim 60
Dependent Claim
37 words
The method defined in claim 55 wherein the step of impacting said piece of lumber includes impacting said piece of lumber when said piece of lumber is positioned in a predetermined location proximal to said impactor means.
Claim 61
Dependent Claim
36 words
The method defined in claim 49 including the step of selecting at least one said predetermined formula corresponding to a selected lumber type from a plurality of predetermined formulas corresponding to a plurality of lumber types.
Claim 62
Dependent Claim
37 words
The method defined in claim 49 wherein said predetermined formula comprises an equation statistically derived from said predetermined parameters and said at least one selected physical parameter for a plurality of destructively tested pieces of said lumber.
Claim 63
Dependent Claim
33 words
The method defined in claim 58 wherein said equation defines the statistically optimum predictor of said at least one selected physical parameter of said lumber as a function of said selected predetermined parameters.
Claim 64
Dependent Claim
63 words
The method defined in claim 49 including the steps of: supporting said piece of lumber between said impacting means and said detecting means; and operating said impactor means to impact a first surface of said piece of lumber and said detector means to provide a signal related to the compression force generated in said piece of lumber at a second opposite surface thereof.
Claim 65
Dependent Claim
40 words
The method defined in claim 60 wherein supporting said piece of lumber includes supporting said piece of lumber edgewise with a first longitudinal end adjacent to said impactor means and a second opposite longitudinal end adjacent to said detector means.
Claim 66
Dependent Claim
31 words
The method defined in claim 60 wherein said first surface comprises a first longitudinal end of said lumber and said second surface comprises a second opposite longitudinal end of said lumber.
Claim 67
Dependent Claim
50 words
The method defined in claim 49 including the step of: automatically sequentially positioning individual pieces of said lumber between said impacting means and said detecting means with a first surface of said lumber being adjacent to said impacting means and a second opposite surface being adjacent to said detecting means.
Claim 68
Dependent Claim
31 words
The method defined in claim 63 wherein said first surface comprises a first longitudinal end of said lumber and said second surface comprises a second opposite longitudinal end of said lumber.
Claim 69
Dependent Claim
28 words
The method defined in claim 49 further comprising the step of: isolating said piece of material from mechanical vibration before said impacting means impacts said piece of lumber.
Claim 70
Dependent Claim
149 words
A lumber feeding apparatus, comprising: rotatable lumber receiving means comprising a drive shaft and a plurality of carousel wheels mounted on said drive shaft in spaced relation, each one of said carousel wheels including a corresponding plurality of compartments aligned for receiving at least one piece of lumber and means for isolating said at least one piece of lumber from mechanical vibrations; conveyor means for continuously transporting a plurality of pieces of lumber to said lumber receiving means; means for restraining said plurality of pieces of lumber on said conveyor means; means for selectively releasing said restraining means to allow a selected number of pieces of lumber to be transported to said lumber receiving means; and means for rotating said lumber receiving means after said lumber receiving means receives said selected number of pieces of lumber so that said selected number of pieces are rotated to a processing position.
Claim 71
Dependent Claim
149 words
A lumber feeding apparatus, comprising: rotatable lumber receiving means comprising a drive shaft and a plurality of carousel wheels mounted on said drive shaft in spaced relation, each one of said carousel wheels including a corresponding plurality of compartments aligned for receiving at least one piece of lumber and means for isolating said at least one piece of lumber from mechanical vibrations; conveyor means for continuously transporting a plurality of pieces of lumber to said lumber receiving means; means for restraining said plurality of pieces of lumber on said conveyor means; means for selectively releasing said restraining means to allow a selected number of pieces of lumber to be transported to said lumber receiving means; and means for rotating said lumber receiving means after said lumber receiving means receives said selected number of pieces of lumber so that said selected number of pieces are rotated to a processing position.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-07-24 | 1993-01-23 | 1993-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-07-24 | 1997-01-23 | 1997-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-07-24 | 2001-01-23 | 2001-07-25 | $7700.00 | Window Closed / Lapsed |