Produce grader

Claim 1

A method for sorting articles of produce according to a known characteristic manifested in radiation received therefrom and for sorting produce articles from nonvegetable articles, comprising passing desired articles of produce along with mingled undesired nonvegetable articles through an inspection position, detecting the presence of an article of the inspection position, receiving radiation from the article at the inspection position, in response to the received radiation determining if the detected article manifests said known characteristic by a predetermined amount, in response to the received radiation determining if the detected article is vegetable matter or nonvegetable matter, performing a first operation on a detected article if it manifests the known characteristic by the desired amount and is vegetable matter, and performing a different operation on a detected article if it does not manifest the known characteristic by the desired amount or is nonvegetable matter.

Claim 2

A method for sorting articles of produce according to a known characteristic manifested in radiation received therefrom and for sorting produce articles from nonvegetable articles, comprising passing desired articles of produce along with mingled undesired nonvegetable articles through an inspection position, detecting the presence of an article of the inspection position, receiving radiation from the article at the inspection position, in response to the received radiation determining if the detected article manifests said known characteristic by a predetermined amount, in response to the received radiation determining if the detected article is vegetable matter or nonvegetable matter, performing a first operation on a detected article if it manifests the known characteristic by the desired amount and is vegetable matter, and performing a different operation on a detected article if it does not manifest the known characteristic by the desired amount or is nonvegetable matter.

Claim 3

A method for sorting articles of produce according to a desired color characteristic of the produce and for sorting desired produce articles from mingled undesirable nonvegetable matter, wherein said articles of produce and nonvegetable matter are mingled together on a moving conveyor and moved past an inspection position, the steps comprising determining if an article is at the inspection position, determining if an article at the inspection position exhibits the desired color characteristic, determining if an article at the inspection position is vegetable matter, performing a given operation only if all of said determinations are affirmative.

Claim 4

A method for sorting articles of produce according to a desired color characteristic of the produce and for sorting desired produce articles from mingled undesirable nonvegetable matter, wherein said articles of produce and nonvegetable matter are mingled together on a moving conveyor and moved past an inspection position, the steps comprising determining if an article is at the inspection position, determining if an article at the inspection position exhibits the desired color characteristic, determining if an article at the inspection position is vegetable matter, performing a given operation only if all of said determinations are affirmative.

Claim 5

A method for sorting articles of produce according to their color characteristics and for sorting produce articles to be retained from nonvegetable articles, comprising passing through an inspection position the articles of produce to be sorted along with nonvegetable articles mingled therewith, illuminating said inspection position with light in a band of wavelengths that includes visible and invisible light, detecting the presence of an article at the inspection position and producing a first electrical signal in response thereto, receiving light from an illuminated article at the inspection position and producing a second electrical signal corresponding only to a predetermined amount of received visible light at first wavelength associated with a desired color characteristic of the produce to be retained, receiving light from an illuminated article at the inspection position and producing a third electrical signal corresponding only to a predetermined amount of received invisible light at a wavelength that is absorbed by the produce to be retained but not by nonvegetable articles, directing the inspected article to a first path only in response to the presence of all three of said signals, directing the inspected article to a different path in response the absence of either one of said second and third signals.

Claim 6

A method for sorting articles of produce according to their color characteristics and for sorting produce articles to be retained from nonvegetable articles, comprising passing through an inspection position the articles of produce to be sorted along with nonvegetable articles mingled therewith, illuminating said inspection position with light in a band of wavelengths that includes visible and invisible light, detecting the presence of an article at the inspection position and producing a first electrical signal in response thereto, receiving light from an illuminated article at the inspection position and producing a second electrical signal corresponding only to a predetermined amount of received visible light at first wavelength associated with a desired color characteristic of the produce to be retained, receiving light from an illuminated article at the inspection position and producing a third electrical signal corresponding only to a predetermined amount of received invisible light at a wavelength that is absorbed by the produce to be retained but not by nonvegetable articles, directing the inspected article to a first path only in response to the presence of all three of said signals, directing the inspected article to a different path in response the absence of either one of said second and third signals.

Claim 7

A method for sorting articles of a given produce according to a desired color characteristic and for separating produce articles to be retained from undesired articles such as dirt clods and rocks, comprising passing through an inspection position the given articles of produce to be sorted along with undesired mingled dirt clods and rocks, illuminating the inspection position with light in a band of wavelengths that includes a narrow band of visible light centered at a wavelength corresponding to the wavelength of the desired color characteristic of the given produce, and two narrow bands of invisible light, one of the invisible bands being centered at a wavelength characterized by significant reflectance from vegetable matter that includes the given produce as well as from dirt clods and rocks, and the other invisible band being centered at a wavelength characterized by an absorption by said vegetable matter that includes the given produce but no absorption by dirt clods and rocks, receiving reflected light from articles of produce, dirt clods, and rocks passing through the inspection position, producing first, second, and third electrical signals corresponding, respectively, to the amount of light that exceeds predetermined magnitudes in said visible and two invisible bands, detecting the presence of said signals corresponding to received light in one of the invisible light bands to determine if an article is present at the inspection position, comparing said second and third signals to determine if an article present at the inspection position is vegetable matter rather than a dirt clod or a rock, comparing said first signal with one of the other of said signals to determine if a detected article at the inspection position has the desired color characteristic, taking no sorting action if the first one of the above determinations is negative, directing a detected article along a predetermined path if all of the above determinations are affirmative, and directing a detected article along a different path if either of the last two determinations are negative.

Claim 8

A method for sorting articles of a given produce according to a desired color characteristic and for separating produce articles to be retained from undesired articles such as dirt clods and rocks, comprising passing through an inspection position the given articles of produce to be sorted along with undesired mingled dirt clods and rocks, illuminating the inspection position with light in a band of wavelengths that includes a narrow band of visible light centered at a wavelength corresponding to the wavelength of the desired color characteristic of the given produce, and two narrow bands of invisible light, one of the invisible bands being centered at a wavelength characterized by significant reflectance from vegetable matter that includes the given produce as well as from dirt clods and rocks, and the other invisible band being centered at a wavelength characterized by an absorption by said vegetable matter that includes the given produce but no absorption by dirt clods and rocks, receiving reflected light from articles of produce, dirt clods, and rocks passing through the inspection position, producing first, second, and third electrical signals corresponding, respectively, to the amount of light that exceeds predetermined magnitudes in said visible and two invisible bands, detecting the presence of said signals corresponding to received light in one of the invisible light bands to determine if an article is present at the inspection position, comparing said second and third signals to determine if an article present at the inspection position is vegetable matter rather than a dirt clod or a rock, comparing said first signal with one of the other of said signals to determine if a detected article at the inspection position has the desired color characteristic, taking no sorting action if the first one of the above determinations is negative, directing a detected article along a predetermined path if all of the above determinations are affirmative, and directing a detected article along a different path if either of the last two determinations are negative.

Claim 9

A method for sorting articles of a given produce according to a desired red color of that produce and for sorting undesired articles such as dirt clods and rocks from desired produce articles to be retained, comprising passing through an inspection position the given articles of produce to be sorted along with mingled dirt clods and rocks, illuminating said inspection position with light in a band of wavelengths that includes a narrow band of visible red light centered approximately at 660 nm and two narrow bands of infra red light respectively centered at approximately 800 nm and 990 nm, receiving light reflected from articles passing through said inspection position, producing a first signal in response to a given amount of received red light in said visible band, producing a second signal in response to a given amount of received invisible light in said 800 nm band, producing a third signal in response to a given amount of received invisible light in said 990 nm band, comparing one of said second or third signals with a reference signal to produce an article signal only when said second or third signal exceeds the reference signal by a given magnitude, thereby indicating that an article to be sorted is at said inspection position, comparing said first signal with one of said second or third signals to produce a color signal only when the magnitude of the first signal exceeds the magnitude of the second or third signal by a given magnitude, thereby indicating that an article having desired red color is being inspected, comparing said second and third signals to produce a vegetable signal only when said second signal exceeds said third signal by a given magnitude, thereby indicating that the article being inspected is vegetable matter and not a dirt clod or rock, directing the inspected article along a first path in response to the simultaneous occurrence of said color, said article, and said vegetable signals, and directing the inspected article along a different path upon occurrence of the article signal but in the absence of said color signal or said vegetable signal.

Claim 10

A method for sorting articles of a given produce according to a desired red color of that produce and for sorting undesired articles such as dirt clods and rocks from desired produce articles to be retained, comprising passing through an inspection position the given articles of produce to be sorted along with mingled dirt clods and rocks, illuminating said inspection position with light in a band of wavelengths that includes a narrow band of visible red light centered approximately at 660 nm and two narrow bands of infra red light respectively centered at approximately 800 nm and 990 nm, receiving light reflected from articles passing through said inspection position, producing a first signal in response to a given amount of received red light in said visible band, producing a second signal in response to a given amount of received invisible light in said 800 nm band, producing a third signal in response to a given amount of received invisible light in said 990 nm band, comparing one of said second or third signals with a reference signal to produce an article signal only when said second or third signal exceeds the reference signal by a given magnitude, thereby indicating that an article to be sorted is at said inspection position, comparing said first signal with one of said second or third signals to produce a color signal only when the magnitude of the first signal exceeds the magnitude of the second or third signal by a given magnitude, thereby indicating that an article having desired red color is being inspected, comparing said second and third signals to produce a vegetable signal only when said second signal exceeds said third signal by a given magnitude, thereby indicating that the article being inspected is vegetable matter and not a dirt clod or rock, directing the inspected article along a first path in response to the simultaneous occurrence of said color, said article, and said vegetable signals, and directing the inspected article along a different path upon occurrence of the article signal but in the absence of said color signal or said vegetable signal.