Claims
- 1. A door system comprising, a door movable between a closed vertical position and an open horizontal position, a cable attached to said door and normally providing a counterbalancing force to said door, said cable extending along a vertical line adjacent said door and being normally substantially taut, and an anti-drop assembly having a pawl pivotally supported on said door and attached to said cable, a stop surface positioned adjacent to said door, and a spring operable to urge said pawl toward engagement with said stop surface, wherein when taut the cable opposes the biasing force of said spring and wherein upon the cable going slack said spring urges said pawl into engagement with said stop surface to decelerate said door.
- 2. The door system of claim 1 further comprising, a mounting bracket attached to an edge of the door, a pivot member supported on said bracket extending axially outward therefrom and adapted to receive said pawl.
- 3. The door system of claim 2, wherein said spring has a first end and a second end, said first end engaging said pawl and said second end engaging said mounting bracket, wherein said spring is adapted to apply force between said mounting bracket and said pawl urging said pawl toward engagement with said stop surface.
- 4. The door system of claim 3, wherein said mounting bracket includes a keeper adapted to engage said second end of said spring.
- 5. The door system of claim 4, wherein said keeper is a member extending laterally outward from said mounting bracket adjacent said pawl.
- 6. The door system of claim 5, wherein said pawl has a pivot portion and said member extends adjacent said body portion of said pawl and defines a clearance for said pivot portion of said pawl.
- 7. The door system of claim 6 further comprising, a boss extending axially outward from said mounting plate, wherein said pivot portion is rotatably supported on said boss.
- 8. The door system of claim 7, wherein said boss defines a bore adapted to receive a shaft of a roller.
- 9. The door system of claim 7, wherein said boss is cylindrical and said pawl defines a circular opening adapted to fit over said boss.
- 10. The door system of claim 1, wherein said pawl includes a head extending toward the stop surface, and wherein said spring urges said head toward engagement with the stop surface.
- 11. The door system of claim 10, wherein said pawl has a body portion and said head extends from said body portion.
- 12. The door system of claim 11, wherein said head extends from the top of said body portion.
- 13. The door system of claim 12, wherein said head extends generally perpendicular to said body portion and has a tip that is angled outwardly toward the stop surface from a top of said head to a bottom thereof.
- 14. The door system of claim 11, wherein said head extends at an oblique angle relative to said body portion.
- 15. The door system of claim 14, wherein said pawl has a pivot portion and said head extends from said pivot portion of said pawl.
- 16. The door system of claim 15, wherein said head has a tip oriented at an acute angle relative to said stop surface.
- 17. The door system of claim 1, wherein said pawl has a body portion that defines a spring bore with said spring being at least partially received within said spring bore.
- 18. The door system of claim 17, wherein said spring is a ball plunger having a spring-loaded plunger housed within a hollow casing, wherein said casing is secured within said spring bore and said spring loaded plunger is axially moveable relative to said casing to apply the biasing force.
- 19. The door system of claim 18, wherein said casing is threadably received within said spring bore.
- 20. The door system of claim 1, wherein said pawl has a cable bore adapted to receive an end of said cable and wherein said end of said cable is secured to said pawl within said cable bore.
- 21. The door system of claim 20 further comprising a first bore in registry with said cable bore and a fastener insertable through said first bore and protruding into said cable bore, whereby said fastener clamps said cable within said cable bore.
- 22. The door system of claim 21 further comprising a stud supported in said pawl and in registry with said cable bore and located in opposition to said first bore, whereby said cable is clamped between said stud and said fastener.
- 23. The door system of claim 22 further comprising a second bore and a second stud both in registry with said cable bore and located in opposition to each other; and a second fastener insertable within said second bore to clamp said cable to said pawl.
- 24. The door system of claim 22, wherein said stud tapers radially inwardly toward said fastener.
- 25. The door system of claim 1, wherein said stop surface is formed of a resilient polymer to permit an extent of temporary deformation upon engagement by said pawl.
- 26. In a door system having a door movable between a closed vertical position and an open horizontal position and having a cable interconnected to said door near the bottom thereof and extending along a vertical line adjacent said door and being normally substantially taut, an anti-drop assembly comprising, a pawl having a body portion interconnected with the cable and a pivot portion pivotally supported on the door, a stop surface mounted adjacent to the door, and means for biasing said pawl toward engagement with said stop surface, whereby said cable, when taut, holds the pawl against the force of said means for biasing and whereby when the tension is released from the cable said means for biasing urges said pawl into engagement with said stop surface to decelerate the door.
- 27. The anti-drop assembly of claim 26, wherein said stop surface includes at least one surface adapted to positively engage a portion of said pawl.
- 28. The anti-drop assembly of claim 27, wherein said surface adapted to positively engaged portion of said pawl is oriented normal to the direction of fall of the door.
- 29. The anti-drop assembly of claim 26, wherein said stop surface includes a notch adapted to receive a portion of said pawl.
- 30. An anti-drop door system comprising, a vertically movable door, a cable attached to said door and normally providing a counterbalancing force to said door, said cable extending adjacent said door and being normally substantially taut, and an anti-drop assembly having a pawl pivotally supported on said door and attached to said cable, a stop surface positioned adjacent to said door, and a spring operable to urge said pawl toward engagement with said stop surface, wherein when taut the cable opposes the biasing force of said spring and wherein upon the cable going slack, said spring urges said pawl into engagement with said stop surface to decelerate said door.
- 31. A method of impeding free-fall of a sectional door vertically movable in tracks caused by loss of tension in a cable that counterbalances the door comprising the steps of, providing a stop surface adjacent the track, pivotally mounting a pawl on the door, biasing said pawl to rotate toward an engaged position with said stop surface, attaching the cable to the pawl such that the cable when taut opposes the biasing force on said pawl and when slack permits the biasing force on said pawl to urge said pawl into the engaged position with said stop surface to decelerate and stop the door.
RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 09/948,086 filed Sep. 6, 2001.
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
09948086 |
Sep 2001 |
US |
Child |
10104465 |
Mar 2002 |
US |