US4122831A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solar collector comprising an elongate absorber in an evacuated transparent tube
Assignee: US Philips Corp
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Filing: 1977-04-08
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Granted: 1978-10-31
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Expires: 1997-04-08
Abstract
Abstract A solar collector comprising an elongate absorber centrally arranged in an evacuated, transparent, circular-cylindrical tube provided with a reflector in the form of a 1/3-circular cylinder in contact with the absorber.
Inventors
- 👤 Faramarz Mahdjuri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:46
CPC Classifications
F; F24; F24S; F24S10/00; F24S10/40; F24S10/45; F24S10/70; F24S10/74; F24S10/90; F24S10/95; F24S23/00; F24S23/70; F24S23/74; Y; Y02; Y02E; Y02E10/00; Y02E10/40; Y02E10/44
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
164 words
A solar collector which comprises a sealed and evacuated transparent tube that has a circular cross-section over at least a portion of its length, an internal reflector having an arcuate cross-section of substantially 120° and extending substantially co-extensive with said length portion, and an absorber having at least one duct for transferring heat derived from solar radiation incident on the absorber to a heat transport medium in the duct during operation and extending longitudinally of said tube with its largest transverse dimension in the symmetry plane of said internal reflector, said absorber being centrally arranged in the tube, said reflector being in engagement with the absorber and intersecting the tube at points situated at the ends of the tube circle diameter perpendicular to the internal reflector symmetry plane, and the centre of the circle including the internal reflector arc being situated on the internal reflector symmetry plane such that circle radii extend through the reflector/tube points of intersection and are tangent to the absorber.
Claim 2
Dependent Claim
164 words
A solar collector which comprises a sealed and evacuated transparent tube that has a circular cross-section over at least a portion of its length, an internal reflector having an arcuate cross-section of substantially 120° and extending substantially co-extensive with said length portion, and an absorber having at least one duct for transferring heat derived from solar radiation incident on the absorber to a heat transport medium in the duct during operation and extending longitudinally of said tube with its largest transverse dimension in the symmetry plane of said internal reflector, said absorber being centrally arranged in the tube, said reflector being in engagement with the absorber and intersecting the tube at points situated at the ends of the tube circle diameter perpendicular to the internal reflector symmetry plane, and the centre of the circle including the internal reflector arc being situated on the internal reflector symmetry plane such that circle radii extend through the reflector/tube points of intersection and are tangent to the absorber.
Claim 3
Dependent Claim
18 words
A solar collector according to claim 1, in which the internal reflector comprises a foil of flexible material.
Claim 4
Dependent Claim
16 words
A solar collector according to claim 2, in which the foil is connected to the absorber.
Claim 5
Dependent Claim
17 words
A solar collector according to claim 2, in which the foil is resiliently arranged in the tube.
Claim 6
Dependent Claim
44 words
A solar collector according to claim 1, in which at each end of the tube length portion of circular cross-section a flat reflector element extends transversely of the tube axis, said elements also serving to keep the absorber in position relative to the tube.
Claim 7
Dependent Claim
27 words
A solar collector according to claim 1, in which each end of the tube is dome-shaped and is provided with a reflective layer on its inner surface.
Claim 8
Dependent Claim
47 words
A solar collector according to claim 1, in which the inner surface of the tube is provided with a light-transmitting but infrared-reflective layer over at least the length portion of circular cross-section, said layer being situated on the same side of the internal reflector as the absorber.
Claim 9
Dependent Claim
40 words
A solar collector according to claim 1, in which the absorber is provided with a surface layer of a material having an absorption factor α ≧ 0.85 for solar radiation and an emission factor ε ≦ 0.3 for heat radiation.
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) | 1981-10-30 | 1982-05-01 | 1982-10-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-30 | 1986-05-01 | 1986-10-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-30 | 1990-05-01 | 1990-10-31 | $7700.00 | Window Closed / Lapsed |