Method of and apparatus for dimensionally inspecting an article with a pair of radiant energy beams

Claim 2

In a method of ascertaining a relationship between a linear dimension of a first member with respect to a known linear dimension of a second member: scanning the first member with a first detector along the linear dimension thereof; initiating the generation of a first pulse train at a first frequency upon the first detector passing over the origin of, and until the first detector passes over the termination of, the linear dimension of the first member; counting and storing the pulses of the first pulse train; scanning the second member with a second detector along the known linear dimension thereof; initiating the generation of a second pulse train at a second frequency upon the second detector passing over the origin of, and until the second detector passes over the termination of, the known linear dimension of the second member, the second frequency being at a value to generate a pulse train having a pulse count equal to the pulse count of the first pulse train when the ratio of the linear dimension of the first member to the known linear dimension of the second member is equal to a known constant; applying the pulses of the second pulse train to sequentially subtract the stored pulse count of the first pulse train, and generating an indication signal upon retention of a stored count of the first pulse train which is indicative of a ratio of the linear dimension of the first member to the known linear dimension of the second member that is not equal to the known constant.

Claim 3

In a method of ascertaining a relationship between a known linear dimension of a first member with respect to a linear dimension of a second member; scanning the first member with a first detector along the known linear dimension thereof; initiating the generation of a first pulse train at a first frequency upon the first detector passing over the origin of, and until the first detector passes over the termination of, the known linear dimension of the first member; counting and storing the pulses of the first pulse train; scanning the second member with a second detector along the linear dimension thereof; initiating the generation of a second pulse train at a second frequency upon the second detector passing over the origin of, and until the second detector passes over the termination of, the linear dimension of the second member, the second frequency being at a value to generate a pulse train having a pulse count equal to the pulse count of the first pulse train when the ratio of the known linear dimension of the first member to the linear dimension of the second member is equal to a known constant; applying the pulses of the second pulse train to sequentially subtract the stored pulse count of the first pulse train, and generating an indication signal upon retention of a stored count of the first pulse train which is indicative of a ratio of the known linear dimension of the first member to the linear dimension of the second member that is not equal to the known constant.

Claim 4

In a method of ascertaining a relationship between a known linear dimension of a first member with respect to a linear dimension of a second member; scanning the first member with a first detector along the known linear dimension thereof; initiating the generation of a first pulse train at a first frequency upon the first detector passing over the origin of, and until the first detector passes over the termination of, the known linear dimension of the first member; counting and storing the pulses of the first pulse train; scanning the second member with a second detector along the linear dimension thereof; initiating the generation of a second pulse train at a second frequency upon the second detector passing over the origin of, and until the second detector passes over the termination of, the linear dimension of the second member, the second frequency being at a value to generate a pulse train having a pulse count equal to the pulse count of the first pulse train when the ratio of the known linear dimension of the first member to the linear dimension of the second member is equal to a known constant; applying the pulses of the second pulse train to sequentially subtract the stored pulse count of the first pulse train, and generating an indication signal upon retention of a stored count of the first pulse train which is indicative of a ratio of the known linear dimension of the first member to the linear dimension of the second member that is not equal to the known constant.

Claim 5

In a method of determining whether an unknown dimension of an article is greater than, or less than, a predetermined dimension: imparting relative movement between a first beam of radIant energy and the article to scan the beam across the article along the unknown dimension thereof; detecting when the first beam is scanned across the unknown dimension of the article; advancing a count at a frequency F1 into a counter, having a known initial count, while the first beam is scanned across the unknown dimension of the article; imparting relative movement between a second beam of radiant energy and a member having a known dimension to scan the beam across the member, along the known dimension thereof, at essentially the same velocity as the first beam scans across the unknown dimension of the article; detecting when the second beam is scanned across the known dimension of the member; subtracting a count at a frequency F2 from the counter while the second beam is scanned across the known dimension of the member, the frequencies F1 and F2 satisfying the ratio F2/F1 predetermined dimension/known dimension of the member, and comparing, after the advancing and subtracting steps, the final count in the counter with the initial count, whereby the unknown dimension is less than, or greater than, the predetermined dimension in accordance with whether the final count has reached, or is greater than, respectively, the initial count.

Claim 6

In a method of determining whether an unknown dimension of an article is greater than, or less than, a predetermined dimension: imparting relative movement between a first beam of radIant energy and the article to scan the beam across the article along the unknown dimension thereof; detecting when the first beam is scanned across the unknown dimension of the article; advancing a count at a frequency F1 into a counter, having a known initial count, while the first beam is scanned across the unknown dimension of the article; imparting relative movement between a second beam of radiant energy and a member having a known dimension to scan the beam across the member, along the known dimension thereof, at essentially the same velocity as the first beam scans across the unknown dimension of the article; detecting when the second beam is scanned across the known dimension of the member; subtracting a count at a frequency F2 from the counter while the second beam is scanned across the known dimension of the member, the frequencies F1 and F2 satisfying the ratio F2/F1 predetermined dimension/known dimension of the member, and comparing, after the advancing and subtracting steps, the final count in the counter with the initial count, whereby the unknown dimension is less than, or greater than, the predetermined dimension in accordance with whether the final count has reached, or is greater than, respectively, the initial count.

Claim 7

In the method as set forth in claim 3, wherein: the step of imparting relative movement between the first beam and the article comprises scanning the first beam of radiant energy along a path which crosses the article along the unknown dimension thereof to intercept the beam, with the article, while it is scanned across the unknown dimension; the step of imparting relative movement between the second beam and the member comprises scanning the second beam of radiant energy along a path which crosses the member along the known dimension thereof, at essentially the same velocity as the first beam crosses the article along the unknown dimension, to intercept the beam, with the member, while it is scanned across the known dimension; the step of detecting when the first beam is scanned across the unknown dimension of the article comprises detecting when the first beam is intercepted by the article alon the unknown dimension thereof, and the step of detecting when the second beam is scanned across the known dimension of the member comprises detecting when the second beam is intercepted by the member along the known dimension thereof.

Claim 8

In the method as set forth in claim 4, wherein the two scanning steps are sequential.

Claim 9

In a method of comparing an unknown dimension of an article with a predetermined dimension: imparting relative movement between a first beam of radiant energy and the article to scan the beam across the article along the unknown dimension thereof; detecting when the first beam is scanned across the unknown dimension of the article; subtracting a count, at a frequency F1, from a counter, having a known initial count, while the first beam is scanned across the unknown dimension of the article; imparting relative movement between a second beam of radiant energy and a member having a known dimension to scan the beam across the member, along the known dimension thereof, at essentially the same velocity as the first beam scans across the unknown dimension of the article; detecting when the second beam is scanned across the known dimension of the member; advancing a count, at a frequency F2, into the counter while the second beam is scanned across the known dimension of the member, the frequencies F1 and F2 satisfying the ratio F2/F1 predetermined dimension/known dimension of the member, and comparing, after the advancing and the subtracting steps, the final count in the counter with the initial count, whereby the unknown dimension of the article is less than, or greater than, the predetermined dimension, in accorDance with whether the final count in the counter is greater than, or has reached, respectively, the initial count.

Claim 10

In a method of comparing an unknown dimension of an article with a predetermined dimension: imparting relative movement between a first beam of radiant energy and the article to scan the beam across the article along the unknown dimension thereof; detecting when the first beam is scanned across the unknown dimension of the article; subtracting a count, at a frequency F1, from a counter, having a known initial count, while the first beam is scanned across the unknown dimension of the article; imparting relative movement between a second beam of radiant energy and a member having a known dimension to scan the beam across the member, along the known dimension thereof, at essentially the same velocity as the first beam scans across the unknown dimension of the article; detecting when the second beam is scanned across the known dimension of the member; advancing a count, at a frequency F2, into the counter while the second beam is scanned across the known dimension of the member, the frequencies F1 and F2 satisfying the ratio F2/F1 predetermined dimension/known dimension of the member, and comparing, after the advancing and the subtracting steps, the final count in the counter with the initial count, whereby the unknown dimension of the article is less than, or greater than, the predetermined dimension, in accorDance with whether the final count in the counter is greater than, or has reached, respectively, the initial count.

Claim 11

In the method as set forth in claim 6, wherein: the step of imparting relative movement between the first beam and the article comprises scanning the first beam of radiant energy along a path which crosses the article along the unknown dimension thereof to intercept the beam, with the article, while it is scanned across the unknown dimension; the step of imparting relative movement between the second beam and the member comprises scanning the second beam of radiant energy along a path which crosses the member along the known dimension thereof, at essentially the same velocity as the first beam crosses the article along the unknown dimension, to intercept the beam, with the member, while it is scanned across the known dimension; the step of detecting when the first beam is scanned across the unknown dimension of the article comprises detecting when the first beam is intercepted by the article along the unknown dimension thereof, and the step of detecting when the second beam is scanned across the known dimension of the member comprises detecting when the second beam is intercepted by the member along the known dimension thereof.

Claim 12

In the method as set forth in claim 7, wherein the two scanning steps are sequential.

Claim 13

In a method of ascertaining the existence of a predetermined relationship of a first dimension of a first quantity with respect to a second dimension of a second quantity: scanning the first and second quantities with a detector for detecting the origins and terminations of the first and the second dimensions; sensing the origin of the first dimension to initiate the generation and the storage of a first train of pulses at a first frequency until the sensing of the origin of the second dimension; sensing the termination of the second dimension to initiate the generation of a second train of pulses at the first frequency until the sensing of the termination of the first dimension; initiating the generation and storage of a third train of pulses, upon sensing the origin of the second dimension and until sensing the termination of the second dimension, at a second frequency sufficient to generate a number of pulses at least equal to the number of pulses in each of the stored first and second trains of pulses if the predetermined relationship exists; applying the third train of pulses to sequentially subtract all the pulses in the stored first train of pulses, and applying the second train of pulses to sequentially subtract less than all the pulses in the stored third train of pulses, if there is the predetermined relationships between the first and second dimensions, and generating an indicating signal if the predetermined relationship does not exist.

Claim 14

In a method of ascertaining the existence of a predetermined relationship of a first dimension of a first quantity with respect to a second dimension of a second quantity: scanning the first and second quantities with a detector for detecting the origins and terminations of the first and the second dimensions; sensing the origin of the first dimension to initiate the generation and the storage of a first train of pulses at a first frequency until the sensing of the origin of the second dimension; sensing the termination of the second dimension to initiate the generation of a second train of pulses at the first frequency until the sensing of the termination of the first dimension; initiating the generation and storage of a third train of pulses, upon sensing the origin of the second dimension and until sensing the termination of the second dimension, at a second frequency sufficient to generate a number of pulses at least equal to the number of pulses in each of the stored first and second trains of pulses if the predetermined relationship exists; applying the third train of pulses to sequentially subtract all the pulses in the stored first train of pulses, and applying the second train of pulses to sequentially subtract less than all the pulses in the stored third train of pulses, if there is the predetermined relationships between the first and second dimensions, and generating an indicating signal if the predetermined relationship does not exist.

Claim 15

In a method of ascertaining whether first and second edges of an article each overhang an individual one of first and second edges of a support by an amount less than, or in excess of, a predetermined amount, the article having a width between its first and second edges which is greater than the width of the support between its first and second edges, and the article being positioned on the support with its width parallel to the width of the support and with its first and second edges overhanging the first and second edges, respectively, of the support, the first and second edges of the support extending beyond the length of the article and the distance between the first and second edges of the support being known: scanning a pair of parallel beams of radiant energy along paths to scan the first beam across the article from the first to the second edge thereof, and to scan the second beam across the support from the first to the second edge thereof, to intercept the first beam, from passing beyond the article, with the article between the first and second edges thereof and to intercept the second beam, from passing beyond the suppOrt, with the support between the first and the second edges thereof, the beams being oriented such that a plane therebetween is parallel to the edges of the support; detecting when the first beam is intercepted by the article and when the second beam is intercepted by the support; advancing a count at a frequency F1 into a first counter having a known initial count, when the first beam is intercepted by the first edge of the article and until the second beam is intercepted by the first edge of the support; subtracting a count at a frequency F2 from the first counter, and advancing a count at the frequency F2 into a second counter having a known initial count, when the second beam is intercepted by the first edge of the support and until the second beam scans across the second edge of the support, the frequencies F1 and F2 satisfying the ratio F2/F1 predetermined amount of overhang of the article/known width of the support; generating a first signal, when the second beam scans across the second edge of the support, having a first state if the count in the first counter has reached the initial count therein to indicate that the first edge of the article overhangs the first edge of the support by less than the predetermined amount, and having a second state if the count in the first counter is greater than the initial count therein to indicate that the first edge of the article overhangs the first edge of the support in excess of the predetermined amount; subtracting a count at the frequency F1 from the second counter when the second beam scans across the second edge of the support and until the first beam scans across the second edge of the article, and generating a second signal, when the first beam scans across the second edge of the article, having a first state if the count in the second counter has reached the initial count therein to indicate that the second edge of the article overhangs the second edge of the support in excess of the predetermined amount, and having a second state if the count in the second counter is greater than the initial count therein to indicate that the second edge of the article overhangs the second edge of the support by less than the predetermined amount.

Claim 16

In a method of ascertaining whether first and second edges of an article each overhang an individual one of first and second edges of a support by an amount less than, or in excess of, a predetermined amount, the article having a width between its first and second edges which is greater than the width of the support between its first and second edges, and the article being positioned on the support with its width parallel to the width of the support and with its first and second edges overhanging the first and second edges, respectively, of the support, the first and second edges of the support extending beyond the length of the article and the distance between the first and second edges of the support being known: scanning a pair of parallel beams of radiant energy along paths to scan the first beam across the article from the first to the second edge thereof, and to scan the second beam across the support from the first to the second edge thereof, to intercept the first beam, from passing beyond the article, with the article between the first and second edges thereof and to intercept the second beam, from passing beyond the suppOrt, with the support between the first and the second edges thereof, the beams being oriented such that a plane therebetween is parallel to the edges of the support; detecting when the first beam is intercepted by the article and when the second beam is intercepted by the support; advancing a count at a frequency F1 into a first counter having a known initial count, when the first beam is intercepted by the first edge of the article and until the second beam is intercepted by the first edge of the support; subtracting a count at a frequency F2 from the first counter, and advancing a count at the frequency F2 into a second counter having a known initial count, when the second beam is intercepted by the first edge of the support and until the second beam scans across the second edge of the support, the frequencies F1 and F2 satisfying the ratio F2/F1 predetermined amount of overhang of the article/known width of the support; generating a first signal, when the second beam scans across the second edge of the support, having a first state if the count in the first counter has reached the initial count therein to indicate that the first edge of the article overhangs the first edge of the support by less than the predetermined amount, and having a second state if the count in the first counter is greater than the initial count therein to indicate that the first edge of the article overhangs the first edge of the support in excess of the predetermined amount; subtracting a count at the frequency F1 from the second counter when the second beam scans across the second edge of the support and until the first beam scans across the second edge of the article, and generating a second signal, when the first beam scans across the second edge of the article, having a first state if the count in the second counter has reached the initial count therein to indicate that the second edge of the article overhangs the second edge of the support in excess of the predetermined amount, and having a second state if the count in the second counter is greater than the initial count therein to indicate that the second edge of the article overhangs the second edge of the support by less than the predetermined amount.

Claim 17

In a method as set forth in claim 10, wherein the detecting steps comprise: focusing the first and second beams, which pass beyond the article and support, respectively, without being intercepted thereby, onto a photodetector for sensing when both beams are incident thereon, when only the second beam is incident thereon, and when neither beam is incident thereon, and for generating an output signal in accordance therewith; generating, in response to the output signal from the photodetector, a third signal having a leading edge occurring when the first beam is intercepted by the first edge of the article and a lagging edge occurring when the first beam scans across the second edge of the article, and generating, in response to the output signal from the photodetector, a fourth signal having a leading edge occurring when the second beam is intercepted by the first edge of the support and a lagging edge occurring when the second beam scans across the second edge of the support.

Claim 18

In a method as set forth in claim 11, wherein: the step of advancing a count at the frequency F1 into the first counter comprises detecting the leading edges of the third and fourth signals and advancing the count, at the frequency F1, into the first counter when the leading edge of the third signal is detected and until the leading edge of the fourth signal is detected; the step of subtracting a count at the frequency F2 from the first counter and advancing a count at the frequency F2 into the second counter comprises detecting the lagging edge of the second signal and subtracting a count at the frequency F2 from the first counter, and advancing a count at the frequency F2 into the second counter, when the leading edge of the fourth signal is detected and until the lagging edge thereof is detected, and the step of subtracting a count at the frequency F1 from the second counter comprises detecting the lagging edge of the third signal and subtracting a count at the frequency F1 from the second counter when the lagging edge of the fourth signal is detected and until the lagging edge of the third signal is detected.

Claim 19

In a system for measuring an unknown dimension of an article with respect to a predetermined dimension: means for imparting relative movement between a first beam of radiant energy and the article to scan the first beam across the article along the unknown dimension thereof and to intercept the first beam, with the article, as it is scanned across the unknown dimension; means for imparting relative movement between a second beam of radiant energy and a member having a known dimension to scan the beam across the member, along the known dimension thereof, at essentially the same velocity as the first beam is scanned across the unknown dimension of the article, to intercept the second beam, with the member, as it is scanned across the known dimension thereof; means for detecting when the first beam is intercepted by the article along the unknown dimension thereof and when the second beam is intercepted by the member along the known dimension thereof; a counter for receiving a clock signal and for selectively increasing or decreasing the count therewithin at a rate in accordance with the frequency of the clock signal; means, responsive to the detecting means, for applying a clock signal at a frequency F1 to the counter to advance a count into the counter at the frequency F1 during the time that the first beam is intercepted by the article along the unknown dimension thereof; means, responsive to the detecting means, for applying a clock signal at a frequency F2 to the counter for subtracting a count from the counter at the frequency F2 during the time that the second beam is intercepted by the member along the known dimension thereof, the frequencies F1 and F2 satisfying the ratio F2/F1 the predetermined dimension/the known dimension of the member, and means, responsive after the first beam has scanned across the unknown dimension of the article and the second beam has scanned across the known dimension of the member, for generating a signal having a first state if the count subtracted from the counter is at least equal to the count advanced into the counter to indicate that the unknown dimension of the article is less than the predetermined dimension, and having a second state if the count subtracted from the counter is less than the count advanced into the counter to indicate that the unknown dimension of the article is in excess of the predetermined dimension.

Claim 20

In a system for measuring an unknown dimension of an article with respect to a predetermined dimension: means for imparting relative movement between a first beam of radiant energy and the article to scan the first beam across the article along the unknown dimension thereof and to intercept the first beam, with the article, as it is scanned across the unknown dimension; means for imparting relative movement between a second beam of radiant energy and a member having a known dimension to scan the beam across the member, along the known dimension thereof, at essentially the same velocity as the first beam is scanned across the unknown dimension of the article, to intercept the second beam, with the member, as it is scanned across the known dimension thereof; means for detecting when the first beam is intercepted by the article along the unknown dimension thereof and when the second beam is intercepted by the member along the known dimension thereof; a counter for receiving a clock signal and for selectively increasing or decreasing the count therewithin at a rate in accordance with the frequency of the clock signal; means, responsive to the detecting means, for applying a clock signal at a frequency F1 to the counter to advance a count into the counter at the frequency F1 during the time that the first beam is intercepted by the article along the unknown dimension thereof; means, responsive to the detecting means, for applying a clock signal at a frequency F2 to the counter for subtracting a count from the counter at the frequency F2 during the time that the second beam is intercepted by the member along the known dimension thereof, the frequencies F1 and F2 satisfying the ratio F2/F1 the predetermined dimension/the known dimension of the member, and means, responsive after the first beam has scanned across the unknown dimension of the article and the second beam has scanned across the known dimension of the member, for generating a signal having a first state if the count subtracted from the counter is at least equal to the count advanced into the counter to indicate that the unknown dimension of the article is less than the predetermined dimension, and having a second state if the count subtracted from the counter is less than the count advanced into the counter to indicate that the unknown dimension of the article is in excess of the predetermined dimension.

Claim 21

In a system as set forth in claim 13, wherein: the means for imparting relative movement between the first beam and the article includes means for scanning the first beam along a path which crosses the article along the unknown dimension thereof; the means for imparting relative movement between the second beam and the member includes means for scanning the second beam along a path which crosses the member along the known dimension thereof, at essentially the same velocity as the first beam crossed the article along the unknown dimension thereof, and the detecting means includes photodetecting means, positioned on the sides of the article and member opposite from the sides thereof which intercept the first and second beams, for detecting the first and second beams which pass beyond the article and the member, respectively, without being intercepted thereby, and for generating signals in accordance therewith.

Claim 22

In the system as set forth in claim 14 wherein the means for scanning the first beam across the article, and the means for scanning the second beam across the member, sequentially scan the first beam across the article and the second beam across the member.

Claim 23

In a system for comparing an unknown dimension of an article with a predetermined dimension: means for imparting relative movement between a first beam of radiant energy and the article to scan the first beam across the article along the unknown dimension thereof and to intercept the first beam, with the article, as it is scanned across the unknown dimension; means for imparting relative movement between a second beam of radiant energy and a member having a known dimension to scan the beam across the member, along the known dimension thereof, at essentially the same velocity as the first beam is scanned across the unknown dimension of the article, to intercept the second beam, with the member, as it is scanned across the known dimension thereof; means for detecting when the first beam is intercepted by the article along the unknown dimension thereof and when the second beam is intercepted by the member along the known dimension thereof; a counter for receiving a clock signal and for selectively increasing or decreasing the count therewithin at a rate in accordance with the frequency of the clock signal; means, responsive to the detecting means, for applying a clock signal at a frequency F2 to the counter to advance a count into the counter at the frequency F2 during the time that the second beam is intercepted by the member along the known dimension thereof; means, responsive to the detecting means for applying a clock signal at a frequency F1 to the counter for subtracting a count from the counter at the frequency F1 during the time that the first beam is intercepted by the article along the unknown dimension thereof, the frequencies F1 and F2 satisfying the ratio F2/F1 the predetermined dimension/the known dimension of the member, and means, responsive after the first beam has scanned across the unknown dimension of the article and the second beam has scanned across the known dimension of the member, for generating a signal having a first state if the count subtracted from the counter is at least equal to the count advanced into the counter to indicate that the unknown dimension of the article is greater than the predetermined dimension, and having a second state if the count subtracted from the counter is less than the count advanced into the counter to indicate that the unknown dimension of the article is less than the predetermined dimension.

Claim 24

In a system for comparing an unknown dimension of an article with a predetermined dimension: means for imparting relative movement between a first beam of radiant energy and the article to scan the first beam across the article along the unknown dimension thereof and to intercept the first beam, with the article, as it is scanned across the unknown dimension; means for imparting relative movement between a second beam of radiant energy and a member having a known dimension to scan the beam across the member, along the known dimension thereof, at essentially the same velocity as the first beam is scanned across the unknown dimension of the article, to intercept the second beam, with the member, as it is scanned across the known dimension thereof; means for detecting when the first beam is intercepted by the article along the unknown dimension thereof and when the second beam is intercepted by the member along the known dimension thereof; a counter for receiving a clock signal and for selectively increasing or decreasing the count therewithin at a rate in accordance with the frequency of the clock signal; means, responsive to the detecting means, for applying a clock signal at a frequency F2 to the counter to advance a count into the counter at the frequency F2 during the time that the second beam is intercepted by the member along the known dimension thereof; means, responsive to the detecting means for applying a clock signal at a frequency F1 to the counter for subtracting a count from the counter at the frequency F1 during the time that the first beam is intercepted by the article along the unknown dimension thereof, the frequencies F1 and F2 satisfying the ratio F2/F1 the predetermined dimension/the known dimension of the member, and means, responsive after the first beam has scanned across the unknown dimension of the article and the second beam has scanned across the known dimension of the member, for generating a signal having a first state if the count subtracted from the counter is at least equal to the count advanced into the counter to indicate that the unknown dimension of the article is greater than the predetermined dimension, and having a second state if the count subtracted from the counter is less than the count advanced into the counter to indicate that the unknown dimension of the article is less than the predetermined dimension.

Claim 25

In a system as set forth in claim 16, wherein: the means for imparting relative movement between the first beam and the article includes means for scanning the first beam along a path which crosses the article along the unknown dimension thereof; the means for imparting relative movement between the second beam and the member includes means for scanning the second beam along a path which crosses the member along the known dimension thereof, at essentially the same velocity as the first beam crossed the article along the unknown dimension thereof, and the detecting means includes photodetecting means, positioned on the sides of the article and member opposite from the sides thereof which intercept the first and second beams, for detecting the first and second beams which pass beyond the article and the member, respectively, without being intercepted thereby, and for generating signals in accordance therewith.

Claim 26

In the system as set forth in claim 17 wherein the means for scanning the first beam across the article, and the means for scanning the second beam across the member, sequentially scan the first beam across the article and the second beam across the member.

Claim 27

In a system for measuring the dimension of the overhang, with respect to a predetermiNed dimension, of each of first and second edges of an article over an individual one of associated first and second edges of a support on which the article is positioned, the first and second edges of the article and support being essentially parallel, the support having a known dimension between its first and second edges and extending, between its first and second edges, beyond the article: means for scanning a pair of parallel beams of radiant energy along paths which scan the first beam across the article from the first to the second edge thereof, and the second beam across the support, along the portion of the support which extends beyond the article, from the first to the second edge thereof, for intercepting the first beam, from passing beyond the article, with the article between the first and second edges thereof, and for intercepting the second beam, from passing beyond the support, with the support between the first and second edges thereof, the beams being oriented such that a plane therebetween is parallel to the edges of the article and the support; photodetecting means for receiving the first and second beams which pass beyond the article and support, respectively, and for generating signals in accordance with whether both beams are incident thereon, only one beam is incident thereon, or neither beam is incident thereon; signal generating means for selectively generating a clock signal at a frequency F1 or F2; first and second counters, each for receiving the clock signal from the signal generating means and for selectively increasing or decreasing the count therewithin at a rate in accordance with the frequency of the clock signal; means, responsive to the signals from the photodetecting means, for applying a clock signal at the frequency F1 from the signal generating means to the first counter to advance a count therein, at the frequency F1, when the first beam is intercepted by the first edge of the article and until the second beam is intercepted by the first edge of the support; means, responsive to the signals from the photodetecting means, for applying a clock signal at the frequency F2 from the signal generating means to the first and second counters to subtract a count from the first counter, and to advance a count into the second counter, at the frequency F2, when the second beam is intercepted by the first edge of the support and until the second beam scans across the second edge of the support, the frequencies F1 and F2 satisfying the ratio F2/F1 the predetermined dimension/the known dimension of the support, means, responsive when the second beam scans across the second edge of the support, for generating a first signal having a first state if the count subtracted from the first counter is at least equal to the count advanced therein to indicate that the dimension of overhang of the first edge of the article over the first edge of the support is less than the predetermined dimension, and having a second state if the count subtracted from the counter is less than the count advanced therein to indicate that the dimension of overhang of the first edge of the article over the first edge of the support is greater than the predetermined dimension; means, responsive to the signals from the photodetecting means, for applying a clock signal at the frequency F1 from the signal generating means to the second counter for subtracting a count therefrom, at the frequency F1, when the second beam scans across the second edge of the support and until the first beam scans across the second edge of the article, and means, responsive when the first beam scans across the second edge of the article, for generating a second signal having a first state if the count subtracted from the second counter is at least equal to the count advanced therein to indicate that the dimension of overhang of the second edge of thE article over the second edge of the support is greater than the predetermined dimension, and having a second state if the count subtracted from the second counter is less than the count advanced therein to indicate that the dimension of overhang of the second edge of the article over the second edge of the support is less than the predetermined dimension.

Claim 28

In a system for measuring the dimension of the overhang, with respect to a predetermiNed dimension, of each of first and second edges of an article over an individual one of associated first and second edges of a support on which the article is positioned, the first and second edges of the article and support being essentially parallel, the support having a known dimension between its first and second edges and extending, between its first and second edges, beyond the article: means for scanning a pair of parallel beams of radiant energy along paths which scan the first beam across the article from the first to the second edge thereof, and the second beam across the support, along the portion of the support which extends beyond the article, from the first to the second edge thereof, for intercepting the first beam, from passing beyond the article, with the article between the first and second edges thereof, and for intercepting the second beam, from passing beyond the support, with the support between the first and second edges thereof, the beams being oriented such that a plane therebetween is parallel to the edges of the article and the support; photodetecting means for receiving the first and second beams which pass beyond the article and support, respectively, and for generating signals in accordance with whether both beams are incident thereon, only one beam is incident thereon, or neither beam is incident thereon; signal generating means for selectively generating a clock signal at a frequency F1 or F2; first and second counters, each for receiving the clock signal from the signal generating means and for selectively increasing or decreasing the count therewithin at a rate in accordance with the frequency of the clock signal; means, responsive to the signals from the photodetecting means, for applying a clock signal at the frequency F1 from the signal generating means to the first counter to advance a count therein, at the frequency F1, when the first beam is intercepted by the first edge of the article and until the second beam is intercepted by the first edge of the support; means, responsive to the signals from the photodetecting means, for applying a clock signal at the frequency F2 from the signal generating means to the first and second counters to subtract a count from the first counter, and to advance a count into the second counter, at the frequency F2, when the second beam is intercepted by the first edge of the support and until the second beam scans across the second edge of the support, the frequencies F1 and F2 satisfying the ratio F2/F1 the predetermined dimension/the known dimension of the support, means, responsive when the second beam scans across the second edge of the support, for generating a first signal having a first state if the count subtracted from the first counter is at least equal to the count advanced therein to indicate that the dimension of overhang of the first edge of the article over the first edge of the support is less than the predetermined dimension, and having a second state if the count subtracted from the counter is less than the count advanced therein to indicate that the dimension of overhang of the first edge of the article over the first edge of the support is greater than the predetermined dimension; means, responsive to the signals from the photodetecting means, for applying a clock signal at the frequency F1 from the signal generating means to the second counter for subtracting a count therefrom, at the frequency F1, when the second beam scans across the second edge of the support and until the first beam scans across the second edge of the article, and means, responsive when the first beam scans across the second edge of the article, for generating a second signal having a first state if the count subtracted from the second counter is at least equal to the count advanced therein to indicate that the dimension of overhang of the second edge of thE article over the second edge of the support is greater than the predetermined dimension, and having a second state if the count subtracted from the second counter is less than the count advanced therein to indicate that the dimension of overhang of the second edge of the article over the second edge of the support is less than the predetermined dimension.

Claim 29

In a system as set forth in claim 19, further including: means, responsive to the signals from the photodetecting means, for generating a third signal having a leading edge occurring when the first beam is intercepted by the first edge of the article and a lagging edge occurring when the first beam scans across the second edge of the article, and for generating a fourth signal having a leading edge occurring when the second beam scans across the first edge of the support and a lagging edge occurring when the second beam scans across the second edge of the support.

Claim 30

In a system as set forth in claim 20, wherein: the means, responsive to the signals from the photodetecting means for applying a clock signal at the frequency F1 to the first counter to advance a count therein, includes means for detecting the leading edges of the third and fourth signals, and for advancing the count at the frequency F1, into the first counter when the leading edge of the third signal is detected and until the leading edge of the fourth signal is detected; the means, responsive to the signals from the photodetecting means, for applying a clock signal at the frequency F2 to the first and second counters to subtract a count from the first counter, and to advance a count into the second counter, at the frequency F2, includes means for detecting the lagging edge of the fourth signal, and for subtracting the count from the first counter, and advancing the count into the second counter, at the frequency F2, when the leading edge of the fourth signal is detected and until the lagging edge of the fourth signal is detected, and the means, responsive to the signals from the photodetecting means, for applying a clock signal at the frequency F1 to the second counter for subtracting a count therefrom, includes means for detecting the lagging edge of the third signal and for subtracting the count, at the frequency F1, from the second counter when the lagging edge of the fourth signal is detected and until the lagging edge of the third signal is detected.

Claim 31

In a method of ascertaining a relationship between a linear dimension of a first member with respect to a known linear dimension of a second member: imparting relative movement between the first member and a first detector to scan the first detector across the first member along the linear dimension thereof; initiating the generation of a first pulse train upon the first detector passing over the origin of, and until the first detector passes over the termination of, the linear dimension of the first member; counting and storing, from an initial count, the pulses of the first pulse train; imparting relative movement between the second member and a second detector to scan the second detector across the second member along the known linear dimension thereof; initiating the generation of a second pulse train upon the second detector passing over the origin of, and until the second detector passes over the termination of, the known linear dimension of the second member, the number of pulses in the second pulse train having a predetermined relationship with the number of pulses in the first pulse train when the ratio of the linear dimension of the first member to the known linear dimension of the second member is equal to a known constant; applying the pulses of the second pulse train to sequentially subtract the stored pulse count, and generating an indication signal upon retention of a stored count which is indicative of the number of pulses in the second pulse train nOt having the predetermined relationship with the number of pulses in the first pulse train, and therefore of a ratio of the linear dimension of the first member to the known linear dimension of the second member that is not equal to the known constant.

Claim 32

In a method of ascertaining a relationship between a linear dimension of a first member with respect to a known linear dimension of a second member: imparting relative movement between the first member and a first detector to scan the first detector across the first member along the linear dimension thereof; initiating the generation of a first pulse train upon the first detector passing over the origin of, and until the first detector passes over the termination of, the linear dimension of the first member; counting and storing, from an initial count, the pulses of the first pulse train; imparting relative movement between the second member and a second detector to scan the second detector across the second member along the known linear dimension thereof; initiating the generation of a second pulse train upon the second detector passing over the origin of, and until the second detector passes over the termination of, the known linear dimension of the second member, the number of pulses in the second pulse train having a predetermined relationship with the number of pulses in the first pulse train when the ratio of the linear dimension of the first member to the known linear dimension of the second member is equal to a known constant; applying the pulses of the second pulse train to sequentially subtract the stored pulse count, and generating an indication signal upon retention of a stored count which is indicative of the number of pulses in the second pulse train nOt having the predetermined relationship with the number of pulses in the first pulse train, and therefore of a ratio of the linear dimension of the first member to the known linear dimension of the second member that is not equal to the known constant.

Claim 33

In a manner of ascertaining a relationship between a known linear dimension of a first member with respect to a linear dimension of a second member: imparting relative movement between the first member and a first detector to scan the first detector across the first member along the known linear dimension thereof; initiating the generation of a first pulse train upon the first detector passing over the origin of, and until the first detector passes over the termination of, the known linear dimension of the first member; counting and storing, from an initial count, the pulses of the first pulse train; imparting relative movement between the second member and a second detector to scan the second detector across the second member along the linear dimension thereof; initiating the generation of a second pulse train upon the second detector passing over the origin of, and until the second detector passes over the termination of, the linear dimension of the second member, the number of pulses in the second pulse train having a predetermined relationship with the number of pulses in the first pulse train when the ratio of the known linear dimension of the first member to the linear dimension of the second member is equal to a known constant; applying the pulses of the second pulse train to sequentially subtract the stored pulse count, and generating an indication signal upon retention of a stored count which is indicative of the number of pulses in the second pulse train not having the predetermined relationship with the number of pulses in the first pulse train, and therefore of a ratio of the known linear dimension of the first member to the linear dimension of the second member that is not equal to the known constant.

Claim 34

In a manner of ascertaining a relationship between a known linear dimension of a first member with respect to a linear dimension of a second member: imparting relative movement between the first member and a first detector to scan the first detector across the first member along the known linear dimension thereof; initiating the generation of a first pulse train upon the first detector passing over the origin of, and until the first detector passes over the termination of, the known linear dimension of the first member; counting and storing, from an initial count, the pulses of the first pulse train; imparting relative movement between the second member and a second detector to scan the second detector across the second member along the linear dimension thereof; initiating the generation of a second pulse train upon the second detector passing over the origin of, and until the second detector passes over the termination of, the linear dimension of the second member, the number of pulses in the second pulse train having a predetermined relationship with the number of pulses in the first pulse train when the ratio of the known linear dimension of the first member to the linear dimension of the second member is equal to a known constant; applying the pulses of the second pulse train to sequentially subtract the stored pulse count, and generating an indication signal upon retention of a stored count which is indicative of the number of pulses in the second pulse train not having the predetermined relationship with the number of pulses in the first pulse train, and therefore of a ratio of the known linear dimension of the first member to the linear dimension of the second member that is not equal to the known constant.