US3751085A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Incremental dead bolt latch
Assignee: NI West Inc
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Filing: 1972-02-07
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Granted: 1973-08-07
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Expires: 1992-02-07
Abstract
Abstract A dead bolt latch for a door has a rotating cam lever action for extending the bolt into a strike plate recess in the door frame. The cam has the form of a pivoted arm and is rotated by the tail piece of a lock device. The pivot axis is near one edge of a lock case and engages a cam opening in an actuator slide at the opposite side of the latch case, the actuator slide being attached to the latch bolt. A series of stepped shoulders on the cam lever serve as blockers to prevent retraction of the actuator slide by pressure against the latch bolt so that the latch bolt can be locked in any one of several extended positions and need not occupy a fully extended position to be assured of there being no unauthorized retraction which might otherwise be possible with a partially extended latch bolt.
Inventors
- 👤 V Sanders
- 👤 D Potter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:02
CPC Classifications
E; E05; E05B; E05B63/00; E05B63/0017; E05B15/00; E05B15/16; E05B15/1614; E05B15/1621; Y; Y10; Y10S; Y10S292/00; Y10S292/52; Y10T; Y10T292/00; Y10T292/08; Y10T292/096; Y10T292/0969; Y10T292/097; Y10T292/0977; Y10T292/0982; Y10T292/0983; Y10T292/1014; Y10T292/1016
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
198 words
A dead bolt latch mechanism for installation in a door and for cooperation with a strike hole in a door frame when in locked position, said mechanism comprising a tubular case for mounting on a door at a free edge thereof, a longitudinal guide means at the inside end of the case adjacent one edge thereof, a cam arm pivotally mounted on a transverse pivot axis at the other edge of the case, said cam arm having oppositely facing cam faces, a bolt assembly including a bolt head reciprocatably mounted in the case and extendable to a position adjacent the bottom of the strike hole in fully extended position, an actuator portion of said bolt assembly having a guide retention means in sliding engagement with the guide means, shoulder means on the actuator having positions of engagement with said cam faces, the cam face which is on the side of the cam lever facing said bolt assembly having a plurality of shoulders thereon spaced at intervals outwardly from the axis rotation, each shoulder being engageable with the respective shoulder on the actuator whereby to lock the latch bolt in each of a plurality of different partially extended positions.
Claim 2
Dependent Claim
198 words
A dead bolt latch mechanism for installation in a door and for cooperation with a strike hole in a door frame when in locked position, said mechanism comprising a tubular case for mounting on a door at a free edge thereof, a longitudinal guide means at the inside end of the case adjacent one edge thereof, a cam arm pivotally mounted on a transverse pivot axis at the other edge of the case, said cam arm having oppositely facing cam faces, a bolt assembly including a bolt head reciprocatably mounted in the case and extendable to a position adjacent the bottom of the strike hole in fully extended position, an actuator portion of said bolt assembly having a guide retention means in sliding engagement with the guide means, shoulder means on the actuator having positions of engagement with said cam faces, the cam face which is on the side of the cam lever facing said bolt assembly having a plurality of shoulders thereon spaced at intervals outwardly from the axis rotation, each shoulder being engageable with the respective shoulder on the actuator whereby to lock the latch bolt in each of a plurality of different partially extended positions.
Claim 3
Dependent Claim
34 words
A dead bolt latch mechanism as in claim 1 wherein there is a yieldable detent acting on the cam lever in all positions of engagement of said cam lever with said latch bolt assembly.
Claim 4
Dependent Claim
36 words
A dead bolt latch mechanism as in claim 2 wherein the yieldable detent is a bent spring having one end in engagement with the bolt assembly and the other end in engagement with the cam lever.
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) | 1976-08-06 | 1977-02-05 | 1977-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-06 | 1981-02-05 | 1981-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-06 | 1985-02-05 | 1985-08-07 | $7700.00 | Window Closed / Lapsed |