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.