US3953940A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Counterforce assembly for doors
Assignee: Individual
•
Filing: 1974-10-17
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Granted: 1976-05-04
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Expires: 1994-10-17
Abstract
Abstract A counterforce assembly is described for use with doors that are exposed to high pressure differentials on the two sides thereof which result in large forces acting on the doors which tend to maintain the same closed against a door jamb and make the same difficult to open. The assembly includes a counterforce panel. The panel is typically hingedly mounted and has one major side thereof covered by a pressure shield. The covered side is vented to the low pressure side of the door and maintained at the low pressure while the other major side of the panel is exposed to the high pressure side, so that the panel is exposed to the same pressure differential as is the door and a resulting net force acts on the panel. Coupling means, which may be in the form of a pressure plate, a fulcrum arm, a linkage or a pulley arrangement, is connected to the panel and releasably connected to the door for applying the force acting on the panel to the door and counteracting the force acting on the door until the latter is opened and the pressures on the two sides of the door are equalized. The panel thereby counteracts the forces acting on the door and facilitates opening of the latter irrespective of the magnitudes of the pressure differentials to which the door and panel are exposed.
Inventors
- 👤 Joseph Zaslow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 16:15
CPC Classifications
E; E05; E05F; E05F1/00; E05F1/002; E06; E06B; E06B5/00; E06B5/10; E06B5/12; E05Y; E05Y2900/00; E05Y2900/10; E05Y2900/13; E05Y2900/132
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
421 words
A counterforce assembly for doors exposed to high pressure differentials on the two sides thereof which result in large forces acting on one side of the door tending to maintain the same closed against a door jamb, the assembly comprising a planar counterforce panel mounted for movement and exposed to substantially the same high pressure differentials to which the door is exposed to result in corresponding large forces acting on one side of said panel; coupling means connected to the door and to said panel for applying the large forces acting on said panel to the door and counteracting the large forces acting on the door so that movement of said panel when coupled to the door counteracts the large forces acting on the door and facilitates opening of the door irrespective of the magnitudes of the pressure differentials to which the door and said panel are exposed; a substantially closed pressure shield having at least one opening, said panel being mounted for substantially transverse movements within said pressure shield to define together with said pressure shield a substantially closed compartment in all positions of said panel, said one side of said panel being exposed through said at least one opening to the exterior of said compartment and to the high pressure side to which said one side of the door is exposed, the other surface of said panel facing the interior of said compartment providing a low pressure side; venting means for venting the interior of said compartment to the low pressure side to which the other side of the door is exposed so that the pressure differential is maintained the same on the door and on said panel in all positions of said panel within said pressure shield; seal means being provided between said pressure shield and said panel to prevent equalization of pressures on the two sides of said panel in the closed position of the door; said coupling means moving said panel and the door together between a first position when the door is closed and a second position when said panel is within said pressure shield and the door is opened an initial degree corresponding to the movement of said panel, said second position of the door breaking the pressure seal at the door to reduce the pressure differential across the door to a negligible quantity, said coupling means permit the door to be opened an additional degree without corresponding movement of said panel, the door being moved said additional degree without assistance of said panel.
Claim 2
Dependent Claim
421 words
A counterforce assembly for doors exposed to high pressure differentials on the two sides thereof which result in large forces acting on one side of the door tending to maintain the same closed against a door jamb, the assembly comprising a planar counterforce panel mounted for movement and exposed to substantially the same high pressure differentials to which the door is exposed to result in corresponding large forces acting on one side of said panel; coupling means connected to the door and to said panel for applying the large forces acting on said panel to the door and counteracting the large forces acting on the door so that movement of said panel when coupled to the door counteracts the large forces acting on the door and facilitates opening of the door irrespective of the magnitudes of the pressure differentials to which the door and said panel are exposed; a substantially closed pressure shield having at least one opening, said panel being mounted for substantially transverse movements within said pressure shield to define together with said pressure shield a substantially closed compartment in all positions of said panel, said one side of said panel being exposed through said at least one opening to the exterior of said compartment and to the high pressure side to which said one side of the door is exposed, the other surface of said panel facing the interior of said compartment providing a low pressure side; venting means for venting the interior of said compartment to the low pressure side to which the other side of the door is exposed so that the pressure differential is maintained the same on the door and on said panel in all positions of said panel within said pressure shield; seal means being provided between said pressure shield and said panel to prevent equalization of pressures on the two sides of said panel in the closed position of the door; said coupling means moving said panel and the door together between a first position when the door is closed and a second position when said panel is within said pressure shield and the door is opened an initial degree corresponding to the movement of said panel, said second position of the door breaking the pressure seal at the door to reduce the pressure differential across the door to a negligible quantity, said coupling means permit the door to be opened an additional degree without corresponding movement of said panel, the door being moved said additional degree without assistance of said panel.
Claim 3
Dependent Claim
132 words
A counterforce assembly as defined in claim 1, wherein the door is hingedly mounted on a hollow frame and wherein said pressure shield includes at least a hollow member exposed to the interior of said compartment, said hollow frame and hollow member being in abutment with each other, apertures being provided in said hollow member portion exposed to said compartment and in said hollow member and frame portions in abutment with each other and in said hollow frame portion exposed to the low pressure side of the door, whereby air within said compartment can be vented through said hollow member and frame when said panel moves into said pressure shield to reduce the effective volume of said compartment and forces out the air therein while maintaining the pressure differential across said panel.
Claim 4
Dependent Claim
129 words
A counterforce assembly as defined in claim 1, wherein the door is hingedly mounted on a hollow frame and wherein said pressure shield is remote from the door and includes at least a hollow member exposed to the interior of said compartment, apertures being provided in said hollow member portion exposed to said compartment and in said frame portion exposed to the low pressure side of the door; and duct means for carrying air between said hollow member and hollow frame, whereby air within said compartment can be vented through said hollow member and frame and said duct means when said panel moves into said pressure shield to reduce the effective volume of said compartment and forces out the air therein while maintaining the pressure differential across said panel.
Claim 5
Dependent Claim
31 words
A counterforce assembly as defined in claim 1, wherein said seal means includes a piano hinge which extends along one edge of said panel about which the latter is pivotally mounted.
Claim 6
Dependent Claim
91 words
A counterforce assembly as defined in claim 1, wherein said panel is mounted for pivotal movement about one edge thereof, the opposing edge of said panel defining an arc during movement of said panel, the surface of said pressure shield defining said major opening portion in abutment with said opposing edge being arcuate and corresponding to the curvature of the arc of movement of said opposing edge, whereby said pressure shield surface and opposing edge are maintained in abutting relationship to provide an air seal in all portions of said panel.
Claim 7
Dependent Claim
131 words
A counterforce assembly as defined in claim 1, wherein said panel and door are hingedly mounted on the same hinge pins, and wherein said coupling means comprises a substantially flat pressure plate connected to said panel, said pressure plate extending beyond the hinged edge of said panel to be disposed in opposition to at least a portion of the low pressure side of the door, said pressure plate abutting against the door and applying a force on the door which tends to open the door when said panel moves in response to the force acting on the same, said pressure plate moving together with said panel and the door between said first and second positions, said pressure plate being stationary with said panel when the door is moved said additional degree.
Claim 8
Dependent Claim
107 words
A counterforce assembly as defined in claim 1, wherein said panel and door include means for being mounted for pivotal movements, said coupling means including linkage means connected to said panel and door for transmitting the large forces acting on said panel to the door, an upwardly directed pin being spaced from and mounted on the door, said linkage means including a link having a hooked free end engageable with said pin in said first position of said panel and when the door is in a closed position, said pin being releasable from said hooked free end when said panel moves from its first to second positions.
Claim 9
Dependent Claim
140 words
A counterforce assembly as defined in claim 1, wherein said panel and the door are pivotally mounted on common hinges, and wherein said coupling means comprises a fulcrum arm connected to an upper edge of said panel and extending beyond the pivoted edge of said panel and at least partially exposed to an upper edge of the door, and a pin provided on the upper edge of the door engageable by said fulcrum arm during movement of said panel so that forces acting on said panel are transmitted to the door by means of said fulcrum arm and said pin to urge the opening of the door, said fulcrum arm being provided with an open ended cutout adapted to receive and release said pin with engagement between said pin and fulcrum arm terminating as said panel reaches said second position.
Claim 10
Dependent Claim
43 words
A counterforce assembly as defined in claim 7, further comprising support means connected to the frame on which the door is mounted and to said hooked free end to support the latter and prevent said linkage means from sagging under its own weight.
Claim 11
Dependent Claim
250 words
A counterforce assembly for doors exposed to high pressure differentials on the two sides thereof which result in large forces acting on the door tending to maintain the same closed against a door jamb, the assembly comprising a planar counterforce panel mounted for movement and exposed to substantially the same high pressure differentials to which the door is exposed to result in net forces acting on said panel; coupling means connected to the door and to said panel for applying the force acting on said panel to the door and counteracting the force acting on the door so that movement of said panel when coupled to the door counteracts the forces acting on the door and facilitates opening of the door irrespective of the magnitudes of the pressure differentials to which the door and said panel are exposed; said panel and door including means for being mounted for pivotal movements; said coupling means including upwardly directed pins spaced from and mounted on the door and on said panel; a lever pivotally mounted proximate each of said pins, each lever having a free end engaged with a respective pin; and a pulley arrangement connecting the other free ends of said levers, movement of said panel and pin mounted thereon causing said panel lever to move said door lever by means of said pulley arrangement, whereby said door lever applies a force to the associated pin and the door which tends to open the same in response to movement of said panel.
Claim 12
Dependent Claim
250 words
A counterforce assembly for doors exposed to high pressure differentials on the two sides thereof which result in large forces acting on the door tending to maintain the same closed against a door jamb, the assembly comprising a planar counterforce panel mounted for movement and exposed to substantially the same high pressure differentials to which the door is exposed to result in net forces acting on said panel; coupling means connected to the door and to said panel for applying the force acting on said panel to the door and counteracting the force acting on the door so that movement of said panel when coupled to the door counteracts the forces acting on the door and facilitates opening of the door irrespective of the magnitudes of the pressure differentials to which the door and said panel are exposed; said panel and door including means for being mounted for pivotal movements; said coupling means including upwardly directed pins spaced from and mounted on the door and on said panel; a lever pivotally mounted proximate each of said pins, each lever having a free end engaged with a respective pin; and a pulley arrangement connecting the other free ends of said levers, movement of said panel and pin mounted thereon causing said panel lever to move said door lever by means of said pulley arrangement, whereby said door lever applies a force to the associated pin and the door which tends to open the same in response to movement of said panel.
Claim 13
Dependent Claim
54 words
A counterforce assembly as defined in claim 10, wherein the free end of said lever mounted proximate the door pin is in the form of an elongate smooth projection disposed between the pin and the door, whereby the door pin is slidably movable with respect to said projection while in abutment against the latter.
Claim 14
Dependent Claim
97 words
A counterforce assembly as defined in claim 11, wherein said panel is movable between first and second positions, said second position of said panel being selected so that said panel and door are coupled only during initial door opening until the pressure seal at the door is broken to reduce the pressure differential across the door to a negligible quantity and the door may be opened to a desired degree without corresponding movement of said panel and without assistance of the latter, engagement between said door pin and projection terminating when said panel reaches said second position.
Claim 15
Dependent Claim
52 words
A counterforce assembly as defined in claim 10, wherein said pulley arrangement comprises a cable, and pulley wheels spaced from each other along the edges of the door and said panel, said cable being guided by said pulley wheels, whereby said pulley arrangement follows the contours of the door and said panel.
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) | 1979-05-04 | 1979-11-03 | 1980-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-04 | 1983-11-03 | 1984-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-04 | 1987-11-03 | 1988-05-04 | $7700.00 | Window Closed / Lapsed |