US4969035A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Observation of furnace interior
Assignee: British Steel PLC
•
Filing: 1989-12-15
•
Granted: 1990-11-06
•
Expires: 2009-12-15
Abstract
Abstract This invention provides a method of observing the interior of a furnace by viewing, at a remote location, the image depicted by a pinhole camera sited in or within the furnace housing. The image may be real and viewed directly or via a reflective or fibre optic transmission system, or alternatively a video camera may be employed, in this instance the `screen` of the camera may be constituted by light responsive elements, e.g. charge coupled devices. The camera may typically be sited in the furnace wall or roof and a pressurized blast of air or an inert gas, e.g. nitrogen or argon, may be employed for maintaining the integrity of the pinhole.
Inventors
- 👤 David I. Dawson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:53
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/0006; C; C21; C21B; C21B7/00; C21B7/24; C21C; C21C5/00; C21C5/28; C21C5/42; C21C5/46; C21C5/4673; F; F27; F27D; F27D21/00; F27D21/02; G02B23/00; G02B23/24; G02B23/2476; G02B23/2492
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
45 words
A method of observing the interior of a furnace comprising viewing, at a remote location, an image depicted by a pinhole camera sited in or within the furnace housing, wherein the image is real and is viewed via a reflective or fibre optic transmission system.
Claim 2
Independent Claim
45 words
A method of observing the interior of a furnace comprising viewing, at a remote location, an image depicted by a pinhole camera sited in or within the furnace housing, wherein the image is real and is viewed via a reflective or fibre optic transmission system.
Claim 3
Dependent Claim
34 words
A method according to claim 1 wherein the image energises elements in the camera responsive to a defined frequency spectra and wherein the image is reproduced at said remote location through electrical signal transmission.
Claim 4
Dependent Claim
57 words
Apparatus for observing the interior of a furnace comprising a pinhole camera sited in or within the furnace housing and means for reproducing for viewing at a remote location the image depicted comprising elements in the camera responsive to a defined frequency spectra and an electrical signal transmission system for reproducing said image at the remote location.
Claim 5
Dependent Claim
57 words
Apparatus for observing the interior of a furnace comprising a pinhole camera sited in or within the furnace housing and means for reproducing for viewing at a remote location the image depicted comprising elements in the camera responsive to a defined frequency spectra and an electrical signal transmission system for reproducing said image at the remote location.
Claim 6
Dependent Claim
109 words
Apparatus for observing the interior of a furnace comprising a pinhole camera sited in or within the furnace housing and means for reproducing for viewing at a remote location the image depicted comprising elements in the camera responsive to a defined frequency spectra and an electrical signal transmission system for reproducing said image at the remote location wherein the camera comprises an inner housing having a sealed aperture aligned with an open aperture in an outer housing and a plate disposed between said apertures in which a pinhole is defined and through which extend rays emanating from the furnace, the rays irradiating the elements mounted within the inner housing.
Claim 7
Dependent Claim
109 words
Apparatus for observing the interior of a furnace comprising a pinhole camera sited in or within the furnace housing and means for reproducing for viewing at a remote location the image depicted comprising elements in the camera responsive to a defined frequency spectra and an electrical signal transmission system for reproducing said image at the remote location wherein the camera comprises an inner housing having a sealed aperture aligned with an open aperture in an outer housing and a plate disposed between said apertures in which a pinhole is defined and through which extend rays emanating from the furnace, the rays irradiating the elements mounted within the inner housing.
Claim 8
Dependent Claim
32 words
Apparatus according to claim 4, in which the inner housing aperture is sealed by a transparent medium, the said rays lying in the visible spectrum and the said elements being light responsive.
Claim 9
Dependent Claim
15 words
Apparatus according to claim 4, in which the pinhole is cleansed by a gas jet.
Claim 10
Dependent Claim
30 words
Apparatus according to claim 6, in which the plate embodies a number of channels through which the gas jet is transmitted to describe flow paths conducive to a cleansing action.
Claim 11
Dependent Claim
45 words
Apparatus according to claim 7, in which the plate comprises two parts, one embodying a conical cavity terminating in the pinhole with channels extending radially from the cavity, and another embodying channels extending tangentially from the periphery of a circular-section recess coaxial with said cavity.
References Cited (Backward Citations)
GB696434A
Cited
GB1002351A
Cited
US3609236A
Cited
US4022530A
Cited
GB1495229A
Cited
US4112763A
Cited
US4432286A
Cited
US4539588A
Cited
JPS6156255A
Cited
US4749171A
Cited
US4820046A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-11-05 | 1994-05-07 | 1994-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-05 | 1998-05-07 | 1998-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-05 | 2002-05-07 | 2002-11-06 | $7700.00 | Window Closed / Lapsed |