US3911953A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Three-plenum mixing dampers
Assignee: NORTHWEST ENG SERVICE
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Filing: 1974-07-05
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Granted: 1975-10-14
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Expires: 1994-07-05
Abstract
Abstract A damper shaft is movable 90* to a second extreme position from a first extreme position in which a by-pass blade keyed rigidly to the shaft extends 45* across a by-pass air passage to fully close the passage; a warm air blade extends parallel to a warm air passage to fully open the warm air passage, and a cold air blade extends 45* across a cold air passage to fully close the cold air passage. In the second extreme position, the by-pass blade extends 45* across and fully closes the by-pass passage; the warm air blade extends 45* across and fully closes the warm air passage, and the cold air blade extends parallel to and fully opens the cold air passage. Lost motion or overrunning couplings couple the warm air blade and the cold air blade in such a manner that these two blades fully close their passages when the shaft is in a third, middle position in which the by-pass blade is parallel to and fully opens the by-pass passages. From the first extreme to the middle position, the by-pass blade is opening, the warm air blade is closing, and the cold air blade is held closed by its overrunning coupling. From the middle to the second extreme position, the by-pass blade is closing, the cold air blade is opening, and the warm air blade is held closed by its overrunning coupling. The overrunning couplings include springs which progressively increase the forces of closing when the shaft is turned further from the closed position of the warm air blade and the cold air blade to ensure minimum leakage.
Inventors
- 👤 Allen P Crombie
- 👤 Roy M Steege
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:12
CPC Classifications
F; F24; F24F; F24F11/00; F24F11/70; F24F11/80; F24F11/81; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/87153; Y10T137/87161; Y10T137/87571; Y10T137/87676; Y10T137/87684; Y10T137/87692
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
215 words
In a three-plenum damper, a by-pass air passage, a warm air passage, a cold aid passage, a by-pass blade movable in the by-pass passage between a first closed position through an open position and a second closed position, a warm air blade movable in the warm air passage between a closed position and an open position, a cold aid blade movable in the cold air passage between a closed position and an open position, drive means for driving the by-pass blade between the first and second closed positions thereof, first resilient coupling means driven by the drive means for moving the warm air blade from the open position thereof to the closed position thereof when the by-pass blade is moved from its first closed position to its open position and for holding the warm air blade in its closed position while the by-pass blade is moved between its open position and its second closed position, and second resilient coupling means for moving the cold air blade from its closed position to its open position while the by-pass blade is moved from its open position to its second closed position and for holding the cold air blade in its closed pOsition while the by-pass blade is moved between its open position and its first closed position.
Claim 2
Dependent Claim
215 words
In a three-plenum damper, a by-pass air passage, a warm air passage, a cold aid passage, a by-pass blade movable in the by-pass passage between a first closed position through an open position and a second closed position, a warm air blade movable in the warm air passage between a closed position and an open position, a cold aid blade movable in the cold air passage between a closed position and an open position, drive means for driving the by-pass blade between the first and second closed positions thereof, first resilient coupling means driven by the drive means for moving the warm air blade from the open position thereof to the closed position thereof when the by-pass blade is moved from its first closed position to its open position and for holding the warm air blade in its closed position while the by-pass blade is moved between its open position and its second closed position, and second resilient coupling means for moving the cold air blade from its closed position to its open position while the by-pass blade is moved from its open position to its second closed position and for holding the cold air blade in its closed pOsition while the by-pass blade is moved between its open position and its first closed position.
Claim 3
Dependent Claim
56 words
The three-plenum damper of claim 1 wherein movement of the by-pass blade is limited to not substantially greater than 90* between its first closed position and its second closed position and movement of each of the warm air blade and the cold air blade between their open and closed positions is limited to about 45* .
Claim 4
Dependent Claim
34 words
The three-plenum damper of claim 2 wherein the drive means comprises a shaft extending through all the passages and keyed to the by-pass damper and connected to the first and second resilient coupling means.
Claim 5
Dependent Claim
28 words
The three-plenum damper of claim 1 wherein the drive means comprises a shaft extending through all the passages and keyed to the first and second resilient coupling means.
Claim 6
Dependent Claim
36 words
The three-plenum damper of claim 4 wherein each resilient coupling means includes an arm keyed to the shaft for pushing its associated blade and spring means urging the last mentioned blade toward engagement with the arm.
Claim 7
Dependent Claim
51 words
The three-plenum damper of claim 5 wherein each spring means comprises a torsion spring having one end engaging the blade and the other end engaging the arm, whereby the spring exerts progressively increasing closing force on the blade as the shaft is turned further beyond the closed position of the blade.
Claim 8
Dependent Claim
37 words
The three-plenum damper of claim 1 wherein each resilient coupling means exerts an increasing closing force as the drive means tends to move the blade driven by that coupling means beyond the closed position of that blade.
Claim 9
Dependent Claim
86 words
In a damper construction, a plurality of parallel passages, a shaft extending through the passages, a plurality of vanes in the passages and mounted on the shaft, means keying a first one of the vanes to the shaft, overrunning resilient coupling means coupling a second one of the vanes to the shaft, and stop means for limiting movement of the second one of the vanes with the shaft through a predetermined angle and permitting the shaft and said first one of the vanes to move further.
Claim 10
Dependent Claim
86 words
In a damper construction, a plurality of parallel passages, a shaft extending through the passages, a plurality of vanes in the passages and mounted on the shaft, means keying a first one of the vanes to the shaft, overrunning resilient coupling means coupling a second one of the vanes to the shaft, and stop means for limiting movement of the second one of the vanes with the shaft through a predetermined angle and permitting the shaft and said first one of the vanes to move further.
Claim 11
Dependent Claim
81 words
In a damper construction, a passage, a shaft extending across the passage, a vane mounted rotatably on the shaft, a pusher arm keyed to the shaft for engaging the vane and moving it with the shaft when the shaft is turned in one direction and tending to move it away from the vane when the shaft is turned in the opposite direction, and spring means between the pusher arm and the vane biasing the vane toward engagement with the pusher arm.
Claim 12
Dependent Claim
81 words
In a damper construction, a passage, a shaft extending across the passage, a vane mounted rotatably on the shaft, a pusher arm keyed to the shaft for engaging the vane and moving it with the shaft when the shaft is turned in one direction and tending to move it away from the vane when the shaft is turned in the opposite direction, and spring means between the pusher arm and the vane biasing the vane toward engagement with the pusher arm.
Claim 13
Dependent Claim
40 words
The damper construction of claim 9 including a pin carried by the arm, the spring being a coiled torsion spring mounted on the pin and having one end connected to the arm and the other end connected to the vane.
Claim 14
Dependent Claim
37 words
The damper construction of claim 9 in which the spring means increases its biasing force on the vane when the vane is in a closed position and the shaft is turned further in a vane closing direction.
Claim 15
Dependent Claim
106 words
In a three-plenum damper, a by-pass passageway, a warm air passageway, a cold air passageway, a blade turnable in each passageway, means for moving the blade so that while air can pass simultaneously through the by-pass passageway and either the warm air or cold air passageway, air is precluded from moving simultaneously through the warm air and cold air passageways, said blades being of such size relative to their passageways that their movement is restricted to approximately 45* from a central position whereby a more constant opening width for the travel of air is attained than with blades permitted to turn 90* from a central position.
Claim 16
Dependent Claim
106 words
In a three-plenum damper, a by-pass passageway, a warm air passageway, a cold air passageway, a blade turnable in each passageway, means for moving the blade so that while air can pass simultaneously through the by-pass passageway and either the warm air or cold air passageway, air is precluded from moving simultaneously through the warm air and cold air passageways, said blades being of such size relative to their passageways that their movement is restricted to approximately 45* from a central position whereby a more constant opening width for the travel of air is attained than with blades permitted to turn 90* from a central position.
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) | 1978-10-13 | 1979-04-14 | 1979-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-13 | 1983-04-14 | 1983-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-13 | 1987-04-14 | 1987-10-14 | $7700.00 | Window Closed / Lapsed |