US4005886A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flush bolt mechanisms
Assignee: Door Controls Inc
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Filing: 1975-12-18
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Granted: 1977-02-01
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Expires: 1995-12-18
Abstract
Abstract A flush bolt mechanism is disclosed for latching the inactive one of a pair of swinging doors, the mechanism functioning to latch the closed inactive door in response to closing of the other door. The latch mechanism includes a bolt that is driven home by cam and spring assemblies. A heat-responsive mechanism is provided for retaining the bolt in its extended position when the heat-responsive mechanism is subjected to a temperature and for a time sufficient to melt one of its components. A release mechanism may be provided for retracting the extended bolt in response to a force of preselected magnitude applied against the inside of the inactive door.
Inventors
- 👤 Douglas E. Lirette
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:02
CPC Classifications
E; E05; E05C; E05C7/00; E05C7/04; E05C7/06; E05B; E05B65/00; E05B65/10; E05B65/104; Y; Y10; Y10S; Y10S292/00; Y10S292/21; Y10T; Y10T292/00; Y10T292/08; Y10T292/0801; Y10T292/0822; Y10T292/0834; Y10T292/0836; Y10T292/0837; Y10T292/0838; Y10T292/0848; Y10T292/0886; Y10T292/0887; Y10T292/089; Y10T292/0908; Y10T292/096; Y10T292/0999
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
328 words
For use in conjunction with a pair of swinging doors, a bolt mechanism comprising a support member having a surface adapted to be mounted essentially flush with the free edge of one of the pair of swinging doors, shaft support means extending from said support member on the side thereof opposite said surface, a first shaft slidably carried adjacent to said surface by said support means and including a latch bolt at one end thereof adapted to be extended beyond a horizontal edge of the door, spring means normally biasing said first shaft to a retracted position, a cam pivotally carried by said support member on an axis parallel to said first shaft and extending beyond the surface thereof and adapted to be engaged by the other of the swinging doors, a cam follower engaged by said cam, said cam follower being pivotally carried by said support member on an axis parallel to said surface and in a plane perpendicular to said first shaft and having a lever arm extending inward beyond said first shaft for movement about the cam follower axis, a second shaft parallel to said first shaft and pivotally carried at one end by the inward distal end of said lever arm and carried at the other end by a said first shaft so that linear movement can be imparted to said first shaft against the bias of said spring means upon generally axial movement of said second shaft in response to pivoting of said cam when engaged by the other of the swinging doors, said second shaft being carried in parallel relationship by said first shaft by a slide connection, and an override spring means normally biasing said second shaft to an extended position relative to said first shaft, the first-named spring means and said over-ride spring means having spring characteristics so that said first-named spring means can be displaced axially by a lesser load than is required to displace said override spring means.
Claim 2
Dependent Claim
328 words
For use in conjunction with a pair of swinging doors, a bolt mechanism comprising a support member having a surface adapted to be mounted essentially flush with the free edge of one of the pair of swinging doors, shaft support means extending from said support member on the side thereof opposite said surface, a first shaft slidably carried adjacent to said surface by said support means and including a latch bolt at one end thereof adapted to be extended beyond a horizontal edge of the door, spring means normally biasing said first shaft to a retracted position, a cam pivotally carried by said support member on an axis parallel to said first shaft and extending beyond the surface thereof and adapted to be engaged by the other of the swinging doors, a cam follower engaged by said cam, said cam follower being pivotally carried by said support member on an axis parallel to said surface and in a plane perpendicular to said first shaft and having a lever arm extending inward beyond said first shaft for movement about the cam follower axis, a second shaft parallel to said first shaft and pivotally carried at one end by the inward distal end of said lever arm and carried at the other end by a said first shaft so that linear movement can be imparted to said first shaft against the bias of said spring means upon generally axial movement of said second shaft in response to pivoting of said cam when engaged by the other of the swinging doors, said second shaft being carried in parallel relationship by said first shaft by a slide connection, and an override spring means normally biasing said second shaft to an extended position relative to said first shaft, the first-named spring means and said over-ride spring means having spring characteristics so that said first-named spring means can be displaced axially by a lesser load than is required to displace said override spring means.
Claim 3
Dependent Claim
96 words
The bolt mechanism that is defined in claim 1, wherein said bolt mechanism includes a keeper for mounting in a door frame and said latch bolt has a beveled edge at its terminal end for engagement with said keeper, said beveled edge being inclined an amount so that a force of a selected magnitude exerted against the door to open it will cause an axial component of force to be exerted against said latch bolt to overcome the spring forces of said override spring means and thereby to move said first shaft to its retracted position.
Claim 4
Dependent Claim
105 words
The bolt mechanism that is defined in claim 1, wherein said bolt mechanism includes a keeper for mounting in a door frame and said latch bolt has a terminal end for engagement with said keeper, said keeper having a beveled edge against which said terminal end can engage, said beveled edge being inclined an amount so that a force of a selected magnitude exerted against the door to open it will cause an axial component of force to be exerted against said latch bolt to overcome the spring forces of said override spring means and thereby to move said first shaft to its retracted position.
Claim 5
Dependent Claim
52 words
The bolt mechanism that is defined in claim 1, wherein said second shaft is axially adjustable relative to the location where it is carried by said first shaft so that the position of said lever arm can be varied to assure contact at all times of the cam follower with said cam.
Claim 6
Dependent Claim
34 words
The bolt mechanism that is defined in claim 1, wherein said first shaft is axially extensible and contractible for adjusting the position of the latch bolt relative to said horizontal edge of the door.
Claim 7
Dependent Claim
42 words
The bolt mechanism that is defined in claim 1, wherein a heat-responsive mechanism is mounted on said support member and is responsive to ambient temperature of a selected magnitude to operate to retain said first shaft against movement toward a retracted position.
Claim 8
Dependent Claim
82 words
The bolt mechanism that is defined in claim 6, wherein said heat-responsive mechanism includes a fusible metal spring retainer and a retention spring normally biased by said spring retainer away from operative engagement of said first shaft, said heat-responsive mechanism being responsive to ambient temperature so that said spring retainer will melt at said temperature to release said retention spring and to allow it to make operative engagement of said first shaft to retain the latter against movement toward its retracted position.
Claim 9
Dependent Claim
94 words
The bolt mechanism that is defined in claim 7, wherein said retention spring is a U-shaped resilient element which straddles said first shaft, the upper ends of the U-shaped resilient element being secured to said support member on one side of said first shaft and the lower end of said U-shaped resilient element being biased away from said first shaft by said spring retainer on the other side of said first shaft, said lower end being movable into operable engagement with said first shaft when said resilient element is released by said spring retainer.
Claim 10
Dependent Claim
32 words
The bolt mechanism that is defined in claim 8, wherein said first shaft has a plurality of axially spaced shoulders for operable engagement by the lower end of said U-shaped resilient element.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-01 | 1980-08-02 | 1981-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-01 | 1984-08-02 | 1985-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-01 | 1988-08-02 | 1989-02-01 | $7700.00 | Window Closed / Lapsed |