US5244240A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Z-bar security system
Assignee: BROOKE-DUVEEN GROUP Ltd
•
Filing: 1992-09-30
•
Granted: 1993-09-14
•
Expires: 2012-09-30
Abstract
Abstract A system for locking a door can: (1) lock the door in dead bolt fashion, (2) allow the door to open a limited distance, or (3) allow the door to open freely. The system has a door-mounted latch assembly that includes a base plate, an intermediate link pivoted to the base plate, and a mode selection and latching assembly that is pivoted to the intermediate link. The latch assembly also includes a high strength, "T"-shaped latch member, and camming means to slide the latch member back and forth as a control knob is rotated. A latch plate is mounted on the door frame in juxtaposition to the door-mounted latch assembly. The latch plate has a cylindrical portion with a vertical slot for receiving the "T"-shaped latch member. A cylindrical sleeve fits inside the cylindrical portion of the latch plate. Like the cylindrical portion of the latch plate, the sleeve has a vertical slot for receiving the latch member. The sleeve also has a horizontal slot running perpendicular to and intersecting with the vertical slot. When the latch member is engaged in the cylindrical portion of the latch plate, the cylindrical sleeve can be rotated so that the latch member is engaged with the horizontal slot in the cylindrical sleeve. The latch member then cannot be directly withdrawn from the latch plate.
Inventors
- 👤 Robert A. Nordmeyer
- 👤 Alvin S. Levenson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 12:30
CPC Classifications
E; E05; E05C; E05C17/00; E05C17/02; E05C17/04; E05C17/32; E05B; E05B63/00; E05B63/0017; E05B63/0065; Y; Y10; Y10T; Y10T292/00; Y10T292/28; Y10T292/282
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
228 words
A Z-Bar door security system providing (1) entry, (2) inspection, and (3) dead bolt modes of operation, comprising: a latch plate for mounting on the frame of the door, said latch plate having a vertical slot for receiving a latch bar; a Z-Bar latch assembly including (1) a base plate for securing to the edge of the door in juxtaposition to said latch plate, (2) an intermediate link pivoted to said base plate at the front edge of said base plate adjacent the door, and (3) a mode selection and latching assembly pivotally mounted to said intermediate link at the front edge of said intermediate link; said mode selection and latching assembly including a rotatably mounted control knob and a high strength latch member, and camming means for linearly advancing said latch member into engagement with said slot in said latch plate as said control knob is rotated, to implement the inspection and the dead bolt modes of operation; means secured to said control knob for securing the base plate, the intermediate link and the mode selection and latching assembly together while the latch member is extended into engagement with the latch plate, thereby providing the dead bolt mode of operation; and said camming means including camming surfaces permitting further rotation of said control knob without retracting the latch member to implement the dead bolt mode of operation.
Claim 2
Dependent Claim
228 words
A Z-Bar door security system providing (1) entry, (2) inspection, and (3) dead bolt modes of operation, comprising: a latch plate for mounting on the frame of the door, said latch plate having a vertical slot for receiving a latch bar; a Z-Bar latch assembly including (1) a base plate for securing to the edge of the door in juxtaposition to said latch plate, (2) an intermediate link pivoted to said base plate at the front edge of said base plate adjacent the door, and (3) a mode selection and latching assembly pivotally mounted to said intermediate link at the front edge of said intermediate link; said mode selection and latching assembly including a rotatably mounted control knob and a high strength latch member, and camming means for linearly advancing said latch member into engagement with said slot in said latch plate as said control knob is rotated, to implement the inspection and the dead bolt modes of operation; means secured to said control knob for securing the base plate, the intermediate link and the mode selection and latching assembly together while the latch member is extended into engagement with the latch plate, thereby providing the dead bolt mode of operation; and said camming means including camming surfaces permitting further rotation of said control knob without retracting the latch member to implement the dead bolt mode of operation.
Claim 3
Dependent Claim
27 words
The Z-Bar door security system as defined in claim 1 wherein said high strength latch member is "T"-shaped, with a crossbar portion at the outer end thereof.
Claim 4
Dependent Claim
31 words
The Z-Bar door security system as defined in claim 1 wherein said latch plate includes a cylindrical tube having said vertical slot for receiving the outer end of said latch member.
Claim 5
Dependent Claim
37 words
The Z-Bar door security system as defined in claim 1 further comprising spring means associated with said base plate and said intermediate link for biasing said intermediate link to lay flat on top of said base plate.
Claim 6
Dependent Claim
30 words
The Z-Bar door security system as defined in claim 1 wherein said mode selection and latching assembly has a top panel having a channel along which said latch member slides.
Claim 7
Dependent Claim
50 words
The Z-Bar door security system as defined in claim wherein a lock pin interconnects said base, said intermediate link and said mode selection and latching assembly while the latch member is extended into engagement with the latch plate, said lock pin comprising a cylindrical shaft with a transversely extending head.
Claim 8
Dependent Claim
68 words
The Z-Bar door security system as defined in claim 2, further comprising means to secure the "T"-shaped latch member into engagement with said latch plate, said means comprising a cylindrical sleeve having a "T"-shaped opening, said cylinder being positioned inside of the cylindrical tube of the latchplate, with a handle affixed to one end of said cylindrical sleeve for rotating said sleeve to engage the "T"-shaped latch member.
Claim 9
Dependent Claim
40 words
The Z-Bar door security system as defined in claim 1, wherein said mode selection and latching assembly includes a mode indicator to display whether the door is deadlocked shut, allowed to open a limited distance, or allowed to open freely.
Claim 10
Dependent Claim
30 words
A Z-Bar security system as defined in claim 1 wherein supplemental movable locking means are mounted to said latch plate for positively locking said latch member to said latch plate.
Claim 11
Dependent Claim
137 words
A Z-Bar door security system providing (1) entry, (2) inspection, and (3) dead bolt modes of operation, comprising: a latch plate for mounting on the frame of a door, said latch plate having a slot for receiving a latch bar; a Z-Bar latch assembly including (1) a base plate for securing to the edge of the door in juxtaposition to said latch plate, (2) an intermediate link pivoted to said base plate, and (3) a mode selection and latching assembly pivotally mounted to said intermediate link; said mode selection and latching assembly including a latch member, and means for linearly advancing said latch member into engagement with said latch plate; and means for locking said base plate, said intermediate link and said latching assembly together without retracting the latch, to implement the dead bolt mode of operation.
Claim 12
Dependent Claim
137 words
A Z-Bar door security system providing (1) entry, (2) inspection, and (3) dead bolt modes of operation, comprising: a latch plate for mounting on the frame of a door, said latch plate having a slot for receiving a latch bar; a Z-Bar latch assembly including (1) a base plate for securing to the edge of the door in juxtaposition to said latch plate, (2) an intermediate link pivoted to said base plate, and (3) a mode selection and latching assembly pivotally mounted to said intermediate link; said mode selection and latching assembly including a latch member, and means for linearly advancing said latch member into engagement with said latch plate; and means for locking said base plate, said intermediate link and said latching assembly together without retracting the latch, to implement the dead bolt mode of operation.
Claim 13
Dependent Claim
16 words
The Z-Bar door security system as defined in claim 10 wherein said latch member is "T"-shaped.
Claim 14
Dependent Claim
27 words
The Z-Bar door security system as defined in claim 10 wherein said latch plate includes a cylindrical tube having said vertical slot for receiving a latch bar.
Claim 15
Dependent Claim
37 words
The Z-Bar door security system as defined in claim 10 further comprising spring means associated with said base plate and said intermediate link for biasing said intermediate link to lay flat on top of said base plate.
Claim 16
Dependent Claim
30 words
The Z-Bar door security system as defined in claim 10 wherein said mode selection and latching assembly has a top panel having a channel along which said latch member slides.
Claim 17
Dependent Claim
50 words
The Z-Bar door security system as defined in claim 10 wherein a lock pin interconnects said base, said intermediate link and said mode selection and latching assembly while the latch is extended into engagement with the latch plate, said lock pin comprising a cylindrical shaft with a transversely extending head.
Claim 18
Dependent Claim
40 words
The Z-Bar door security system as defined in claim 10, wherein said mode selection and latching assembly includes a mode indicator to display whether the door is deadlocked shut, allowed to open a limited distance, or allowed to open freely.
Claim 19
Dependent Claim
68 words
The Z-Bar door security system as defined in claim 11, further comprising means to secure the "T"-shaped latch member into engagement with said latch plate, said means comprising a cylindrical sleeve having a "T"-shaped opening, said cylinder being positioned inside of said cylindrical tube of the latchplate, with a handle affixed to ne end of said cylindrical sleeve for rotating said sleeve to engage the "T"-shaped latch member.
Claim 20
Independent Claim
101 words
A system for pivotally securing a latch to a latch plate mounted on a door frame, said system, comprising: a latch member; a latch plate comprising a cylindrical tube having a slot for receiving said latch member; a cylindrical sleeve having an aperture, said cylindrical sleeve being positioned inside of said cylindrical tube of said latch plate; a handle affixed to one end of said cylindrical sleeve for rotating said sleeve to engage said latch member inside said cylindrical sleeve; and said system including means for permitting partial opening of the door with said latch member secured within said latch plate.
Claim 21
Independent Claim
101 words
A system for pivotally securing a latch to a latch plate mounted on a door frame, said system, comprising: a latch member; a latch plate comprising a cylindrical tube having a slot for receiving said latch member; a cylindrical sleeve having an aperture, said cylindrical sleeve being positioned inside of said cylindrical tube of said latch plate; a handle affixed to one end of said cylindrical sleeve for rotating said sleeve to engage said latch member inside said cylindrical sleeve; and said system including means for permitting partial opening of the door with said latch member secured within said latch plate.
Claim 22
Dependent Claim
35 words
The system for pivotally securing a latch to a latch plate mounted on a door frame of claim 18, in which said latch member is "T"-shaped and comprises a "neck" portion and a "crossbar" portion.
Claim 23
Independent Claim
276 words
A system to secure a latch member of a Z-Bar door latch system to a latch plate, wherein the Z-Bar door latch system provided (1) entry, (2) inspection, and (3) dead bolt modes of operation, the system to secure the latch member comprising: a latch member; a latch plate comprising a cylindrical tube having a slot for receiving said latch member; a cylindrical sleeve having an aperture, said cylindrical sleeve being positioned inside of said cylindrical tube of said latch plate; a handle affixed to one end of said cylindrical sleeve for rotating said sleeve to engage said latch member inside said cylindrical sleeve; a Z-bar latch assembly including (1) a base plate for securing to the edge of a door in juxtaposition to said latch plate, (2) an intermediate link pivoted to said base plate at the front edge of said base plate adjacent the door, and (3) a mode selection and latching assembly pivotally mounted to said intermediate link at the front edge of said intermediate link; said mode selection and latching assembly including a rotatably mounted control knob and said latch member, and camming means for linearly advancing said latch member into engagement with said slot in said latch plate as said control knob is rotated; means secured to said control knob for securing the base plate, the intermediate link and the mode selection and latching assembly together while the latch is extended into engagement with the latch plate, thereby providing the dead bolt mode of operation; and said camming means, including camming surfaces permitting further rotation of said control knob without retracting the latch to implement the head bolt mode of operation.
Claim 24
Independent Claim
276 words
A system to secure a latch member of a Z-Bar door latch system to a latch plate, wherein the Z-Bar door latch system provided (1) entry, (2) inspection, and (3) dead bolt modes of operation, the system to secure the latch member comprising: a latch member; a latch plate comprising a cylindrical tube having a slot for receiving said latch member; a cylindrical sleeve having an aperture, said cylindrical sleeve being positioned inside of said cylindrical tube of said latch plate; a handle affixed to one end of said cylindrical sleeve for rotating said sleeve to engage said latch member inside said cylindrical sleeve; a Z-bar latch assembly including (1) a base plate for securing to the edge of a door in juxtaposition to said latch plate, (2) an intermediate link pivoted to said base plate at the front edge of said base plate adjacent the door, and (3) a mode selection and latching assembly pivotally mounted to said intermediate link at the front edge of said intermediate link; said mode selection and latching assembly including a rotatably mounted control knob and said latch member, and camming means for linearly advancing said latch member into engagement with said slot in said latch plate as said control knob is rotated; means secured to said control knob for securing the base plate, the intermediate link and the mode selection and latching assembly together while the latch is extended into engagement with the latch plate, thereby providing the dead bolt mode of operation; and said camming means, including camming surfaces permitting further rotation of said control knob without retracting the latch to implement the head bolt mode of operation.
Claim 25
Independent Claim
132 words
A system to secure a latch member into engagement with a latch plate, comprising: a latch member; a latch plate comprising a cylindrical tube having a slot for receiving said latch member; a cylindrical sleeve having an aperture, said cylindrical sleeve being positioned inside of said cylindrical tube of said latch plate; a handle affixed to one end of said cylindrical sleeve for rotating said sleeve to engage said latch member inside said cylindrical sleeve; in which said latch member is "T"-shaped and comprises a "neck" portion and a "crossbar" portion; and in which said aperture in said cylindrical sleeve is "T"-shaped, comprising a "neck" portion and a "crossbar" portion, such that said "neck" portion of said "T"-shaped aperture is wide enough to accommodate said "neck" portion of said "T"-shaped latch member.
Claim 26
Independent Claim
132 words
A system to secure a latch member into engagement with a latch plate, comprising: a latch member; a latch plate comprising a cylindrical tube having a slot for receiving said latch member; a cylindrical sleeve having an aperture, said cylindrical sleeve being positioned inside of said cylindrical tube of said latch plate; a handle affixed to one end of said cylindrical sleeve for rotating said sleeve to engage said latch member inside said cylindrical sleeve; in which said latch member is "T"-shaped and comprises a "neck" portion and a "crossbar" portion; and in which said aperture in said cylindrical sleeve is "T"-shaped, comprising a "neck" portion and a "crossbar" portion, such that said "neck" portion of said "T"-shaped aperture is wide enough to accommodate said "neck" portion of said "T"-shaped latch member.
References Cited (Backward Citations)
US1029693A
Cited
US2205156A
Cited
US2407900A
Cited
US3873142A
Cited
US3924887A
Cited
US3924885A
Cited
US3924886A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-09-13 | 1997-03-15 | 1997-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-09-13 | 2001-03-15 | 2001-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-09-13 | 2005-03-15 | 2005-09-14 | $7700.00 | Window Closed / Lapsed |