Apparatus for measuring the thickness of disc-like articles

Claim 1

An apparatus for measuring the thickness of disc-like articles, comprising: first feed means for advancing such articles from a supply thereof, in succession, to an entrance end of a measuring station; gauging means located at said measuring station and including a pair of opposed capacitive probes spaced to receive each advanced article therebetween; circuit means coupled to said probes for applying a predetermined energizing voltage across each probe and an interposed article, and for measuring the value of capacitance thereby established by each probe and the respectively adjacent major surface of the article under measurement, said circuit means further being adapted to provide a capacitance-derived output utilization signal having a magnitude that is correlated with the thickness of the article under measurement; second feed means located at said measuring station, and having an entrance end that communicates with an exit end of said first feed means, for controllably advancing each article, when fed thereto, seriatim, to an exit end of said second feed means along a path that passes between said probes, said second feed means including a drive member with a resilient surface, a feed channel disposed along said path and including a base formed with a probe-exposing aperture therein, and an electrically grounded sidewall-defining portion, the inner surface of which being spaced from said drive member so that each successive article, when advanced into frictional engagement with the resilient surface of said drive member, is continuously advanced by the latter at a predetermined speed with compound rotational and linear displacement along said sidewall-defining portion and between said probes; and a rotatably adjustable platform positioned so as to be adjacent one major surface of each article advancing between said probes, said platform having two spaced sensors mounted thereon and positioned on opposite sides of the pair of probes to sense for angularly adjustable leading and trailing peripheral edge portions on each successively advanced article, and for generating respective output signals in response to such sensed edge portions, whereby said output signals are applied to said circuit means for controlling a time window during which a plurality of thickness measurements are made at different spaced points across the major opposed surfaces of each advancing article.

Claim 2

An apparatus for measuring the thickness of disc-like articles, comprising: first feed means for advancing such articles from a supply thereof, in succession, to an entrance end of a measuring station; gauging means located at said measuring station and including a pair of opposed capacitive probes spaced to receive each advanced article therebetween; circuit means coupled to said probes for applying a predetermined energizing voltage across each probe and an interposed article, and for measuring the value of capacitance thereby established by each probe and the respectively adjacent major surface of the article under measurement, said circuit means further being adapted to provide a capacitance-derived output utilization signal having a magnitude that is correlated with the thickness of the article under measurement; second feed means located at said measuring station, and having an entrance end that communicates with an exit end of said first feed means, for controllably advancing each article, when fed thereto, seriatim, to an exit end of said second feed means along a path that passes between said probes, said second feed means including a drive member with a resilient surface, a feed channel disposed along said path and including a base formed with a probe-exposing aperture therein, and an electrically grounded sidewall-defining portion, the inner surface of which being spaced from said drive member so that each successive article, when advanced into frictional engagement with the resilient surface of said drive member, is continuously advanced by the latter at a predetermined speed with compound rotational and linear displacement along said sidewall-defining portion and between said probes; and a rotatably adjustable platform positioned so as to be adjacent one major surface of each article advancing between said probes, said platform having two spaced sensors mounted thereon and positioned on opposite sides of the pair of probes to sense for angularly adjustable leading and trailing peripheral edge portions on each successively advanced article, and for generating respective output signals in response to such sensed edge portions, whereby said output signals are applied to said circuit means for controlling a time window during which a plurality of thickness measurements are made at different spaced points across the major opposed surfaces of each advancing article.

Claim 5

An apparatus for measuring the thickness of disc-like articles, comprising: first feed means for advancing such articles from a supply thereof, in succession, to an entrance end of a measuring station; gauging means located at said measuring station and including a pair of opposed capacitive probes spaced to receive each advancing article therebetween; circuit means coupled to said probes for applying a predetermined a-c voltage across each probe and an interposed article, and for measuring the value of capacitance thereby established by each probe and the respectively adjacent major surface of the article under measurement, said circuit means further being adapted to provide a capacitance-derived output utilization signal having a magnitude that is correlated with the thickness of the article under measurement; second feed means located at said measuring station, and having an entrance end that communicates with an exit end of said first feed means, for controllably advancing each article, when fed thereto, seriatim, to an exit end of said second feed means along an arcuate path that passes between said probes, said second feed means including a rotatably driven wheel with a resilient peripheral surface, an arcuate feed channel disposed along said path and including a base formed with an aperture therein to expose the probe positioned on the underside thereof to an article when advanced along said base, and an electrically grounded removable sidewall-defining ramp insert, the inner surface of which is spaced from said drive wheel so as to result in each successive article, when advanced into frictional engagement with the resilient peripheral surface of said drive wheel, being compressively biased and electrically grounded against said ramp insert, and being continuously advanced at a predetermined speed with compound rotational and linear displacement along said ramp insert and between said probes; an article sensing assembly including a rotatably adjustable platform positioned so as to be adjacent one major surface of each article when the latter is advanced between said probes, said platform having two spaced photoelectric article sensors mounted thereon to sense for angularly adjustable, predetermined leading and trailing peripheral edge portions, respectively, on each such successively advanced article, and for generating respective output signals in response to such sensed article edge portions, said output signals being applied to said circuit means for controlling a selectively adjustable time window during which a plurality of thickness measurements are made at different spaced points across the major opposed surfaces of each advancing article; and third feed means communicating with an exit end of said second feed means, for directing each article upon being measured to a predetermined storage area.

Claim 6

An apparatus for measuring the thickness of disc-like articles, comprising: first feed means for advancing such articles from a supply thereof, in succession, to an entrance end of a measuring station; gauging means located at said measuring station and including a pair of opposed capacitive probes spaced to receive each advancing article therebetween; circuit means coupled to said probes for applying a predetermined a-c voltage across each probe and an interposed article, and for measuring the value of capacitance thereby established by each probe and the respectively adjacent major surface of the article under measurement, said circuit means further being adapted to provide a capacitance-derived output utilization signal having a magnitude that is correlated with the thickness of the article under measurement; second feed means located at said measuring station, and having an entrance end that communicates with an exit end of said first feed means, for controllably advancing each article, when fed thereto, seriatim, to an exit end of said second feed means along an arcuate path that passes between said probes, said second feed means including a rotatably driven wheel with a resilient peripheral surface, an arcuate feed channel disposed along said path and including a base formed with an aperture therein to expose the probe positioned on the underside thereof to an article when advanced along said base, and an electrically grounded removable sidewall-defining ramp insert, the inner surface of which is spaced from said drive wheel so as to result in each successive article, when advanced into frictional engagement with the resilient peripheral surface of said drive wheel, being compressively biased and electrically grounded against said ramp insert, and being continuously advanced at a predetermined speed with compound rotational and linear displacement along said ramp insert and between said probes; an article sensing assembly including a rotatably adjustable platform positioned so as to be adjacent one major surface of each article when the latter is advanced between said probes, said platform having two spaced photoelectric article sensors mounted thereon to sense for angularly adjustable, predetermined leading and trailing peripheral edge portions, respectively, on each such successively advanced article, and for generating respective output signals in response to such sensed article edge portions, said output signals being applied to said circuit means for controlling a selectively adjustable time window during which a plurality of thickness measurements are made at different spaced points across the major opposed surfaces of each advancing article; and third feed means communicating with an exit end of said second feed means, for directing each article upon being measured to a predetermined storage area.