US3835306A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reflection-type counter
Assignee: Armco Inc
•
Filing: 1972-09-27
•
Granted: 1974-09-10
•
Expires: 1992-09-27
Abstract
Abstract A reflection-type counter for counting a plurality of adjacent edges of reflective material as for example the number of convolutions in a coil of reflective material or the number of sheets in a stack of sheets of reflective material. The counter comprises a light source and means for focusing a beam of light of elliptical cross section from the source onto the edges being counted, the elliptical beam having a minor axis less than the width of the edges upon which it is focused. The beam is so oriented with respect to the edges being counted that both the angle of incidence and the angle of reflectance are substantially perpendicular to the edges being counted. The reflected beam is directed to a photo detector. The voltage output of the photodetector increases as the intensity of the light striking the detector increases. Thus the voltage output of the photodetector is greater when the light beam passes over an edge of the reflective material than when it passes over an interface between edges. Means are provided to process the voltage output of the photodetector into a digital signal. The number of times the signal drops below a predetermined level is counted and displayed. The electronics are such that the number displayed is equal to the number of interfaces passed by the beam plus one, thus giving the actual number of edges present.
Inventors
- 👤 T Bills
- 👤 R Boni
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:14
CPC Classifications
G; G06; G06M; G06M9/00; G06M1/00; G06M1/08; G06M1/10; G06M1/101; B; B65; B65H; B65H2301/00; B65H2301/50; B65H2301/54; B65H2301/541
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
366 words
A reflection-type counter for counting a plurality of adjacent reflective elements with less reflective interfaces therebetween, said counter comprising an optical portion and an electronic portion, said optical portioN comprising a light source, means to direct a beam of light from said source toward and substantially perpendicular to said reflective elements to be counted, means to focus said beam on said reflective elements so that said focused beam has a width less than the width of any one of said reflective elements, a photodetector providing a voltage signal which increases as the intensity of the light impinging upon it increases, means for collecting a part at least of the light reflecting from said reflective elements and the interfaces therebetween, means focusing said reflected light onto said photodetector whereby the voltage signal therefrom is an analogue signal of greater strength when said focused beam passes over said reflective elements and of lesser strength when said focused beam passes over the interfaces between said reflective elements, means to cause said focused beam to scan said reflective elements at a fixed scan speed, said means to focus said beam on said reflective elements and for collecting a part at least of the light reflecting from said reflective elements and interfaces therebetween comprising a first lens, said reflective elements being located in front of said first lens and substantially in the focal plane thereof, said means for focusing said reflected light onto said photodetector comprising a second lens, said first and second lenses being optically aligned, said photodetector being located behind said second lens and on the axis of said first and second lenses, said light source being located to one side of said first and second lenses, said means to direct said beam of light comprising a mirror supported between said first and second lenses and being so oriented as to direct light from said source through said first lens and substantially perpendicularly onto said reflective elements, said electronic portion of said counter comprising means to convert said analogue voltage signal from said photodetector to a digital signal and a digital counter and display means driven by said digital signal and displaying the number of said reflective elements counted.
Claim 2
Dependent Claim
366 words
A reflection-type counter for counting a plurality of adjacent reflective elements with less reflective interfaces therebetween, said counter comprising an optical portion and an electronic portion, said optical portioN comprising a light source, means to direct a beam of light from said source toward and substantially perpendicular to said reflective elements to be counted, means to focus said beam on said reflective elements so that said focused beam has a width less than the width of any one of said reflective elements, a photodetector providing a voltage signal which increases as the intensity of the light impinging upon it increases, means for collecting a part at least of the light reflecting from said reflective elements and the interfaces therebetween, means focusing said reflected light onto said photodetector whereby the voltage signal therefrom is an analogue signal of greater strength when said focused beam passes over said reflective elements and of lesser strength when said focused beam passes over the interfaces between said reflective elements, means to cause said focused beam to scan said reflective elements at a fixed scan speed, said means to focus said beam on said reflective elements and for collecting a part at least of the light reflecting from said reflective elements and interfaces therebetween comprising a first lens, said reflective elements being located in front of said first lens and substantially in the focal plane thereof, said means for focusing said reflected light onto said photodetector comprising a second lens, said first and second lenses being optically aligned, said photodetector being located behind said second lens and on the axis of said first and second lenses, said light source being located to one side of said first and second lenses, said means to direct said beam of light comprising a mirror supported between said first and second lenses and being so oriented as to direct light from said source through said first lens and substantially perpendicularly onto said reflective elements, said electronic portion of said counter comprising means to convert said analogue voltage signal from said photodetector to a digital signal and a digital counter and display means driven by said digital signal and displaying the number of said reflective elements counted.
Claim 3
Dependent Claim
23 words
The structure claimed in claim 1 wherein said reflective elements to be counted comprise the edges of metallic sheets in a stack thereof.
Claim 4
Dependent Claim
22 words
The structure claimed in claim 1 wherein said reflective elements to be counted comprise the convolution edges of a coil of metal.
Claim 5
Dependent Claim
14 words
The structure claimed in claim 1 wherein said source of light comprises a laser.
Claim 6
Dependent Claim
37 words
The structure claimed in claim 1 including an optical filter ahead of said photodetecor, said filter having a center bandpass wavelength and a bandpass so chosen as to pass said reflected light and block out ambient light.
Claim 7
Dependent Claim
20 words
The structure claimed in claim 1 includIng in said electronic portion means to amplify said voltage signal from said photodetector.
Claim 8
Dependent Claim
27 words
The structure claimed in claim 1 including in said electronic portion and bandpass filter ahead of said means to convert said analogue signal to a digital signal.
Claim 9
Dependent Claim
49 words
The structure claimed in claim 1 including a timing circuit between said means to convert said analogue signal to a digital signal and said digital counter, said timing circuit having a time base such as to prevent advancement of said digital counter by spurious signals from said converter means.
Claim 10
Dependent Claim
19 words
The structure claimed in claim 1 wherein said electronic portion is remotely located with respect to said optical portion.
Claim 11
Dependent Claim
22 words
The structure claimed in claim 1 wherein said means to convert said analogue signal to a digital signal comprises a Schmitt trigger.
Claim 12
Dependent Claim
63 words
The structure claimed in claim 1 including a third lens between said light source and said mirror to render said beam elliptical in cross section, said first lens focusing said beam to an ellipse of light having its major axis substantially parallel to said interfaces and its minor axis of a length less than the width of any one of said reflective elements.
Claim 13
Dependent Claim
14 words
The structure claimed in claim 11 wherein said source of light comprises A laser.
Claim 14
Dependent Claim
44 words
The structure claimed in claim 12 including an optical filter ahead of said photodetector, said filter having a center bandpass wavelength and a bandpass so chosen with respect to said laser light source as to pass said reflected light and block out ambient light.
Claim 15
Dependent Claim
30 words
The structure claimed in claim 13 wherein said electronic portion is located remotely of said optical portion, said optical portion including a pre-amplifier for said voltage signal from said photodetector.
Claim 16
Dependent Claim
19 words
The structure claimed in claim 14 wherein said optical portion is mounted in a cabinet a movable optical head.
Claim 17
Dependent Claim
29 words
The structure claimed in claim 15 including means to pass filtered air through said optical head to cool said laser and to prevent dirt from collecting in said head.
Claim 18
Dependent Claim
56 words
The structure claimed in claim 15 including support means for said optical head, said optical head being transversable on said support means in a direction appropriate to cause said focused beam to scan said reflective elements to be counted and motor means operatively connected to said head to traverse said head at a constant scan speed.
Claim 19
Dependent Claim
16 words
The structure claimed in claim 17 wherein said optical head and support means therefor are portable.
References Cited (Backward Citations)
US3422274A
Cited
US3581067A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-09 | 1978-03-11 | 1978-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-09 | 1982-03-11 | 1982-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-09 | 1986-03-11 | 1986-09-10 | $7700.00 | Window Closed / Lapsed |