Method and apparatus for inspecting dielectric members

Claim 3

A method as defined in claim 1 which further includes deriving a reject reference signal from said article-absent signal, and comparing the measurement signal to said reject reference signal to detect a non-acceptable article.

Claim 4

Apparatus for measuring the thickness of an article formed of dielectric material, comprising a. an inspection station including means for establishing a high frequency field at the inspection station which will extend through at least a portion of an article present at the inspection station, b. means for indexing an article into and out of said inspection station, c. means for detecting the high frequency field established at the inspection station and providing an output related in amplitude to the amplitude of the high frequency detected, d. means responsive to the position of said indexing means for receiving said detection output only when an article is not at said inspection station and providing an absent signal output related in amplitude to the received detection output, and e. means for maintaining said absent signal output fixed at the level occurring just before an article is indexed into said inspection station, and means for comparing a detection output when an article is at said inspection station with said fixed absent signal output to derive a thickness signal proportional to the thickness of that portion of the article through which the high frequency field extends.

Claim 5

Apparatus for measuring the thickness of an article formed of dielectric material, comprising a. an inspection station including means for establishing a high frequency field at the inspection station which will extend through at least a portion of an article present at the inspection station, b. means for indexing an article into and out of said inspection station, c. means for detecting the high frequency field established at the inspection station and providing an output related in amplitude to the amplitude of the high frequency detected, d. means responsive to the position of said indexing means for receiving said detection output only when an article is not at said inspection station and providing an absent signal output related in amplitude to the received detection output, and e. means for maintaining said absent signal output fixed at the level occurring just before an article is indexed into said inspection station, and means for comparing a detection output when an article is at said inspection station with said fixed absent signal output to derive a thickness signal proportional to the thickness of that portion of the article through which the high frequency field extends.

Claim 6

Apparatus as defined in claim 3 which further includes a. means for deriving a reject reference signal from said absent signal output which is proportional to an acceptable thickness, and b. means for comparing said thickness signal with said reject reference signal to determine the acceptability of an article.

Claim 7

Apparatus as defined in claim 4 which further includes a. means for relatively moving said article and said high frequency field to obtain a thickness signal for different portions of said article, and in which b. said reject reference and thickness signals comparing means includes means providing an output when an acceptable thickness is detected.

Claim 8

Apparatus as defined in claim 5 which further includes counter means responsive to the detection of an acceptable thickness for indicating the inspection of an article.

Claim 9

Apparatus as defined in claim 5 in which said reject reference and thickness signals cOmparing means further includes means for monitoring said thickness signal to determine whether an article is actually being inspected and for providing a reject signal when an acceptable thickness is not detected during the time an article is being inspected.

Claim 10

Apparatus for measuring the wall thickness of glass containers, comprising a. means for successively moving a series of containers into an inspection station, b. means at said station for rotating the containers about their vertical axes, c. at least one inspection head at said inspection station including means for establishing an electromagnetic field extending through a wall of a container and probe means for sensing the electromagnetic field, d. means responsive to said probe for providing a detection output which varies in amplitude in response to a variance in the electromagnetic field sensed by said probe means, e. means for sensing said detection output only when a container is not present at said inspection station and providing a reference output proportional to said detection output, and f. means for maintaining said reference output fixed while a container is at the station at the level occurring just before a container is moved into the station, and means for receiving said detection output after a container is moved into said station and comparing said detection output to said fixed reference output to derive a signal proportional to the thickness of the wall of said container in said electromagnetic field, thereby automatically compensating for component and ambient variations affecting said detection

Claim 11

Apparatus for measuring the wall thickness of glass containers, comprising a. means for successively moving a series of containers into an inspection station, b. means at said station for rotating the containers about their vertical axes, c. at least one inspection head at said inspection station including means for establishing an electromagnetic field extending through a wall of a container and probe means for sensing the electromagnetic field, d. means responsive to said probe for providing a detection output which varies in amplitude in response to a variance in the electromagnetic field sensed by said probe means, e. means for sensing said detection output only when a container is not present at said inspection station and providing a reference output proportional to said detection output, and f. means for maintaining said reference output fixed while a container is at the station at the level occurring just before a container is moved into the station, and means for receiving said detection output after a container is moved into said station and comparing said detection output to said fixed reference output to derive a signal proportional to the thickness of the wall of said container in said electromagnetic field, thereby automatically compensating for component and ambient variations affecting said detection

Claim 12

Apparatus as defined in claim 8 which further includes a. means responsive to said reference output for providing a reject level signal, and b. means for comparing said thickness signal and said reject level signal to indicate acceptable containers.

Claim 13

Apparatus for measuring the thickness of an article formed of dielectric material, comprising a. means for moving an article into and out of an inspection station, b. means for establishing a high frequency field at the inspection station which will extend through a portion of an article present at the inspection station, c. means for detecting the strength of the field at the inspection station and providing an output which is a measure of the strength of the field, d. means responsive to the action of said article moving means for receiving said field detection output only when an article is not at the inspection station and providing an article-absent output which is a measure of the strength of the field when an article is not present at the inspection station, and e. means for maintaining said article-absent output fixed while an article is at the station at the level occurring just before an article is moved into the station, and means for comparing a detection output when an article is at said inspection station with said fixed article-absent output to provide a signal which is a measure of the thickness of that portion of the article through which said field extends.

Claim 14

Apparatus for measuring the thickness of an article formed of dielectric material, comprising a. means for moving an article into and out of an inspection station, b. means for establishing a high frequency field at the inspection station which will extend through a portion of an article present at the inspection station, c. means for detecting the strength of the field at the inspection station and providing an output which is a measure of the strength of the field, d. means responsive to the action of said article moving means for receiving said field detection output only when an article is not at the inspection station and providing an article-absent output which is a measure of the strength of the field when an article is not present at the inspection station, and e. means for maintaining said article-absent output fixed while an article is at the station at the level occurring just before an article is moved into the station, and means for comparing a detection output when an article is at said inspection station with said fixed article-absent output to provide a signal which is a measure of the thickness of that portion of the article through which said field extends.

Claim 15

Apparatus as defined in claim 10 in which said article-absent output means and said comparing means comprises a. a summer circuit, b. an integrating circuit, and c. switching means operable to close when an article is not at the inspection station, said switching means connecting the output of said summer circuit to the input of said integrating circuit, d. said summer circuit having a first input means for receiving said detection output and a second input means for receiving an output from said integrating circuit.

Claim 16

Apparatus as defined in claim 11 in which said integrating circuit provides an output which changes at a rate determined by the input received, and which provides a fixed output when the input is zero.

Claim 17

Apparatus as defined in claim 11 which further includes a. means for deriving a reject reference signal from the output of said integratiNg circuit, and b. means for comparing the output from said summer circuit with said reject reference signal to provide a reject signal when the thickness of the article is below a minimum acceptable thickness set by the magnitude of said reject reference signal.

Claim 18

Apparatus for measuring the thickness of an article formed of dielectric material, comprising a. means for moving an article into and out of an inspection station; b. means for establishing a high frequency field at the inspection station which will extend through a portion of an article present at the inspection station; c. means for detecting the strength of the field at the inspection station and providing an output which is a measure of the strength of the field; d. means responsive to the action of said article moving means for receiving said field detection output and providing an article-absent output which is a measure of the strength of the field when an article is not present at the inspection station; and e. means for comparing a detection output when an article is at said inspection station with said article-absent output to provide a signal which is a measure of the thickness of that portion of the article through which said field extends; f. said article-absent output means and said comparing means comprising at summer circuit, an integrating circuit, and switching means operable to close when an article is not at the inspection station, said switching means connecting the output of said summer circuit to the input of said integrating circuit, said summer circuit having a first input means for receiving said detection output and a second input means for receiving an output from said integrating circuit, the output of said integrating circuit being connected as a negative feedback to the input of said summer circuit with respect to the detection output being received by said summer circuit, thereby tending to drive the output of said summer circuit toward zero when said switching means is closed.

Claim 19

Apparatus for measuring the thickness of an article formed of dielectric material, comprising a. means for moving an article into and out of an inspection station; b. means for establishing a high frequency field at the inspection station which will extend through a portion of an article present at the inspection station; c. means for detecting the strength of the field at the inspection station and providing an output which is a measure of the strength of the field; d. means responsive to the action of said article moving means for receiving said field detection output and providing an article-absent output which is a measure of the strength of the field when an article is not present at the inspection station; and e. means for comparing a detection output when an article is at said inspection station with said article-absent output to provide a signal which is a measure of the thickness of that portion of the article through which said field extends; f. said article-absent output means and said comparing means comprising at summer circuit, an integrating circuit, and switching means operable to close when an article is not at the inspection station, said switching means connecting the output of said summer circuit to the input of said integrating circuit, said summer circuit having a first input means for receiving said detection output and a second input means for receiving an output from said integrating circuit, the output of said integrating circuit being connected as a negative feedback to the input of said summer circuit with respect to the detection output being received by said summer circuit, thereby tending to drive the output of said summer circuit toward zero when said switching means is closed.

Claim 20

Apparatus for measuring the thickness of an article formed of dielectric material, comprising a. means for moving an article into and out of an inspection station; b. means for establishing a high frequency field at the inspection station which will extend through a portion of an article present at the inspection station; c. means for detecting the strength of the field at the inspection station and providing an output which is a measure of the strength of the field; d. means responsive to the action of said article moving means for receiving said field detection output and providing an article-absent output which is a measure of the strength of the field when an article is not present at the inspection station; e. means for comparing a detection output when an article is at said inspection station with said article-absent output to provide a signal which is a measure of the thickness of that portion or the article through which said field extends; f. said article-absent output means and said comparing means comprising a summer circuit, an integrating circuit, and switching means operable to close when an article is not at the inspection station, said switching means connecting the output of said summer circuit to the input of said integrating circuit, said summer circuit having a first input means for receiving said detection output and a second input means for receiving an output from said integrating circuit; g. means for deriving a reject reference signal from the output of said integrating circuit; and h. means for comparing the output from said summer circuit with said reject reference signal to provide a reject signal when the thickness of the article is below a minimum acceptable thickness set by the magnitude of said reject reference signal; i. said reject reference signal and summer output comparing means including a first comparator circuit having a first input means for receiving said summer output, a seconD input means for receiving said reject reference signal, and output means for providing an output when the summer output exceeds the reject reference signal, and further including a second comparator circuit having input means for receiving said summer output and said first comparator output, and output means providing a reject signal output when said summer output indicates a measurable thickness of an article and the output of said first comparator circuit indicates a below minimum thickness of said article.

Claim 21

Apparatus for measuring the thickness of an article formed of dielectric material, comprising a. means for moving an article into and out of an inspection station; b. means for establishing a high frequency field at the inspection station which will extend through a portion of an article present at the inspection station; c. means for detecting the strength of the field at the inspection station and providing an output which is a measure of the strength of the field; d. means responsive to the action of said article moving means for receiving said field detection output and providing an article-absent output which is a measure of the strength of the field when an article is not present at the inspection station; e. means for comparing a detection output when an article is at said inspection station with said article-absent output to provide a signal which is a measure of the thickness of that portion or the article through which said field extends; f. said article-absent output means and said comparing means comprising a summer circuit, an integrating circuit, and switching means operable to close when an article is not at the inspection station, said switching means connecting the output of said summer circuit to the input of said integrating circuit, said summer circuit having a first input means for receiving said detection output and a second input means for receiving an output from said integrating circuit; g. means for deriving a reject reference signal from the output of said integrating circuit; and h. means for comparing the output from said summer circuit with said reject reference signal to provide a reject signal when the thickness of the article is below a minimum acceptable thickness set by the magnitude of said reject reference signal; i. said reject reference signal and summer output comparing means including a first comparator circuit having a first input means for receiving said summer output, a seconD input means for receiving said reject reference signal, and output means for providing an output when the summer output exceeds the reject reference signal, and further including a second comparator circuit having input means for receiving said summer output and said first comparator output, and output means providing a reject signal output when said summer output indicates a measurable thickness of an article and the output of said first comparator circuit indicates a below minimum thickness of said article.

Claim 22

Apparatus as defined in claim 15 which further includes a. means for relatively moving said article and said field at said inspection station to measure the thickness of different portions of said article, and b. counter means responsive to the output of said first comparator circuit for counting the articles inspected in response to an indication of acceptable thickness of any portion of said article.