US3725666A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-optical determination of wear of paper making screen
Assignee: Individual
•
Filing: 1968-06-17
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Granted: 1973-04-03
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Expires: 1988-06-17
Abstract
Abstract Wear of paper making screen is determined by utilizing increased abraded areas of screen wires for greater reflection of a light beam directed on moving screen. The reflected general beam may also be shifted by reduced thickness of the screen to further affect output of a light sensor, positively on negatively, for comparisons in order to reduce error due to dirty instrument components.
Inventors
- 👤 R Berthold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:40
CPC Classifications
G; G01; G01N; G01N3/00; G01N3/56; G01B; G01B11/00; G01B11/02; G01B11/06; G01N21/00; G01N21/17; G01N21/55
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
221 words
A method for the continuous non-contact indication of the wear of a paper-making machine wire screen, the wires of the screen being substantially round wires, the wear on the screen being attended by the formation of generally flat reflective coplanar surface areas on the wires, with the area of the approximately flat surfaces increasing with the wear of the wires, said method comprising: Directing a light beam from a constant source onto the screen at a predetermined angle to strike areas of wear on the screen so that the incident light on the areas is reflected by the worn areas toward a fixed positioned light sensor; monitoring the amount of light reaching the sensor, the beam being sufficiently large to strike a representative sample of the screen, said screen being of low reflectability toward the sensor when the wires are not worn so that wires not worn produce substantially no light incident on the sensor, the area of the approximately flat surfaces increasing with the wear of the wires thereby providing increasing degree of reflection of the constant beam, with increasing wear, the output of the sensor being dependent on the size of the area of wear on the wires in said sample; and maintaining the face of the screen opposite the reflective areas of wear in a substantially fixed plane.
Claim 2
Independent Claim
221 words
A method for the continuous non-contact indication of the wear of a paper-making machine wire screen, the wires of the screen being substantially round wires, the wear on the screen being attended by the formation of generally flat reflective coplanar surface areas on the wires, with the area of the approximately flat surfaces increasing with the wear of the wires, said method comprising: Directing a light beam from a constant source onto the screen at a predetermined angle to strike areas of wear on the screen so that the incident light on the areas is reflected by the worn areas toward a fixed positioned light sensor; monitoring the amount of light reaching the sensor, the beam being sufficiently large to strike a representative sample of the screen, said screen being of low reflectability toward the sensor when the wires are not worn so that wires not worn produce substantially no light incident on the sensor, the area of the approximately flat surfaces increasing with the wear of the wires thereby providing increasing degree of reflection of the constant beam, with increasing wear, the output of the sensor being dependent on the size of the area of wear on the wires in said sample; and maintaining the face of the screen opposite the reflective areas of wear in a substantially fixed plane.
Claim 3
Dependent Claim
21 words
A method as claimed in claim 1, including providing a signal when a predetermined amount of light impinges on the sensor.
Claim 4
Dependent Claim
58 words
A method as claimed in claim 1, wherein said beam from the constant source is made to strike the screen at a small angle so that the axis of the reflected beam is substantially shifted as the wires of the screen are worn down in order to vary the portion of the reflected beam impinging on the sensor.
Claim 5
Dependent Claim
37 words
A method as claimed in claim 1 wherein the beam is made to strike the screen at a steep angle so that the axis of the beam is not substantially shifted as the wires become worn down.
Claim 6
Dependent Claim
101 words
A method as claimed in claim 4 including directing a second beam on a like representative sample of the wires of the screen at a small angle so that the reflection of the second beam shifts with the wear of the wires, blocking a portion of the reflection of the second beam according to the amount of shift for varying such reflection in a predetermined manner, sensing with a second sensor the amount remaining after blocking, and comparing the outputs of the two sensors for an indication of wear by both beam shift and by degree of reflectability of the wires.
Claim 7
Dependent Claim
26 words
A method as claimed in claim 5, the degree of blocking being substantially proportional to increased reflection of the first mentioned beam due to wire wear.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |