Patent US3750557A successfully refreshed from Google Patents.
US3750557A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for the ventilation of buildings
Assignee: Novenco Building and Industry AS
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Filing: 1971-11-09
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Granted: 1973-08-07
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Expires: 1991-11-09
Abstract
Abstract A system for the ventilation of buildings, comprising vertical and concentrical exhaust and injection ducts extending from a fan section located in the room to be vented to a roof hood and between said ducts a passage for recirculating part of the exhausted air to the injection duct, damper means in the form of a single unit comprising two adjustable damper members being provided in said exhaust and injection ducts and said passage for controlling the ventilation to any desired condition between full supply of fresh air and full recirculation without supply of fresh air, said damper members being constructed as double-walled elements made of a plastic material, in which a porous insulating material may be provided in the cavity between the walls. In a method for manufacturing such a damper member said member is poured from a plastic foam.
Inventors
- 👤 M Osmera
- 👤 C Andersen
- 👤 J Peill
- 👤 A Gerritse
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:10
CPC Classifications
F; F24; F24F; F24F7/00; F24F7/04; F24F7/06; F24F7/08; A; A01; A01K; A01K1/00; A01K1/0047; A01K1/0058
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
202 words
In a system for the ventilation of buildings, for example stables, said system comprising substantially vertical injection and exhaust ducts connecting the interior of the building through the roof thereof to the ambient air; fan means for generating an air flow from the injection duct through the interior of the building to the exhaust duct; a common partition separating said injection and exhaust ducts and including an openIng forming a recirculation passage from the exhaust duct to the injection duct; a damper unit movably positioned in said ducts at said recirculation passage and including at least one damper member arranged to be adjustable to any position between two extreme positions, in one of said extreme positions the damper member is aligned with said common partition and said recirculation passage is closed, and in the other extreme position the damper member extends transversely to the ducts to close both the injection duct and the exhaust duct from the ambient air and open both of said ducts for full recirculation through said recirculation passage, wherein the improvement comprises that said damper member is comprised of a double-walled member, said walls of said member forming a closed cavity and are made from a plastic material.
Claim 2
Dependent Claim
202 words
In a system for the ventilation of buildings, for example stables, said system comprising substantially vertical injection and exhaust ducts connecting the interior of the building through the roof thereof to the ambient air; fan means for generating an air flow from the injection duct through the interior of the building to the exhaust duct; a common partition separating said injection and exhaust ducts and including an openIng forming a recirculation passage from the exhaust duct to the injection duct; a damper unit movably positioned in said ducts at said recirculation passage and including at least one damper member arranged to be adjustable to any position between two extreme positions, in one of said extreme positions the damper member is aligned with said common partition and said recirculation passage is closed, and in the other extreme position the damper member extends transversely to the ducts to close both the injection duct and the exhaust duct from the ambient air and open both of said ducts for full recirculation through said recirculation passage, wherein the improvement comprises that said damper member is comprised of a double-walled member, said walls of said member forming a closed cavity and are made from a plastic material.
Claim 3
Dependent Claim
15 words
The improvement as claimed in claim 1, wherein said plastic material is a fiberglass-reinforced plastic.
Claim 4
Dependent Claim
20 words
The improvement as claimed in claim 1, further comprising supporting ribs of a fiberglass-reinforced plastic material provided in said cavity.
Claim 5
Dependent Claim
17 words
The improvement as claimed in claim 1, wherein said cavity is filled with a porous insulating material.
Claim 6
Dependent Claim
15 words
The improvement as claimed in claim 4, wherein said insulating material consists of plastic foam.
Claim 7
Dependent Claim
24 words
The improvement as claimed in claim 5, wherein the walls of said damper member are formed as non-porous surface layers of the plastic foam.
Claim 8
Dependent Claim
32 words
The improvement as claimed in claim 5, wherein the walls of said damper member are formed as surface layers of a harder non-porous plastic material on the plastic foam and integral therewith.
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) | 1976-08-06 | 1977-02-05 | 1977-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-06 | 1981-02-05 | 1981-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-06 | 1985-02-05 | 1985-08-07 | $7700.00 | Window Closed / Lapsed |