Patent US4912878A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4912878A Expired / Lapsed US ⏱️ 0.0 years remaining

Combined displacing and cushioning means for detention cell doors

Assignee: Stewart Decatur Security Systems Inc
•
Filing: 1988-11-17
•
Granted: 1990-04-03
•
Expires: 2008-11-17
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A mounting assembly is provided for a jail cell door. The door is suspended from a trolley and is slidable, on a fixed rail, between fully open and closed positions. Means are provided for releasably locking the door in either of those positions. Stop means at opposite ends of the rail respectively limit movement of the trolley to the closed and fully open positions. Each stop means includes a compression spring which absorbs shock forces when the door is displaced to its extreme positions. The spring means also provide a force for displacing the door from its closed or fully open positions upon release of the means locking the door in either of these positions.

Inventors

  • 👤 Leroy Bentley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 21:48
CPC Classifications
E; E05; E05F; E05F5/00; E05F5/003; E05B; E05B65/00; E05B65/08; E05B65/087; E05B65/0882; E05B65/0017; E05Y; E05Y2900/00; E05Y2900/10; E05Y2900/13; E05Y2900/132

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 142 words
In a mounting assembly for a sliding door, said assembly comprising a trolley from which the door is suspended, a fixed, horizontal rail on which the trolley is mounted for displacement between extreme positions, respectively being an open and a closed position of the door, and means for releasably locking the door in its closed position, stop means, at opposite ends of said rail, respectively limiting trolley movement to the open and closed positions of the door, each stop means comprising a spring which is compressed during the final portion of trolley movement to an extreme position thereby absorbing shock in arresting trolley and door movement, and the means limiting movement to the closed position of the door, further providing a force for displacing the door to an ajar position when the door is released from being locked in its closed position.
Claim 2
Dependent Claim 142 words
In a mounting assembly for a sliding door, said assembly comprising a trolley from which the door is suspended, a fixed, horizontal rail on which the trolley is mounted for displacement between extreme positions, respectively being an open and a closed position of the door, and means for releasably locking the door in its closed position, stop means, at opposite ends of said rail, respectively limiting trolley movement to the open and closed positions of the door, each stop means comprising a spring which is compressed during the final portion of trolley movement to an extreme position thereby absorbing shock in arresting trolley and door movement, and the means limiting movement to the closed position of the door, further providing a force for displacing the door to an ajar position when the door is released from being locked in its closed position.
Claim 3
Dependent Claim 70 words
A combination as in claim 1 wherein each stop means comprise a fixed tab projecting into the path of trolley movement, a pin slidable in said tab, in the direction of trolley movement, said spring being coiled about said pin, said pin having a head on its inner, which the spring being disposed between said head and said tab, and means maintaining said pin in assembled relation on said tab.
Claim 4
Dependent Claim 154 words
A combination as in claim 1 wherein the door locking means comprise a drop bar, relatively fixed means guiding said drop bar for sliding movement between a raised position and a lower position, and notch means at the bottom of the door which are engaged by the lower end of the drop bar, in the lower position thereof, to lock the door, said trolley including a horizontal bar, said drop bar having a roller disposed in the path of travel of one end of said horizonal bar, when the door is in its closed position and the drop bar is in its lower position, and the spring of the stop means, which limit movement of the trolley to the closed position of the door, displaces the trolley a distance sufficient to dispose the horizontal bar beneath the drop bar roller, when the drop bar is raised to release the door from its locked condition.
Claim 5
Dependent Claim 97 words
A combination as in claim 3 wherein a fixed transom is provided above the entryway controlled by the door, the rail is mounted thereon, each stop means comprise a tab disposed at the end of the rail and having a hole therethrough aligned with the direction of trolley movement, a pin slidable in said tab hole, said pin having a head on its inner end, with said spring being disposed between said tab and said head, and a nut threaded on the outer end of said pin to maintain the pin in assembled relation on the tab.
Claim 6
Dependent Claim 63 words
A combination as in claim 1 wherein means are provided for releasably locking said door in its fully open position, and the spring of the stop means limiting movement of the trolley to the fully open door position, further provides a force for displacing the door away from its fully open position, upon release of the means locking the door in that position.
Claim 7
Dependent Claim 256 words
A combination as in claim 5 wherein the door locking means comprise a drop bar, relatively fixed means guiding said drop bar for sliding movement between a raised position and a lower position, and notch means at the bottom of the door which are selectively engaged by the lower end of the drop bar, in the lower position thereof, to lock the door in it closed or fully open position, said trolley includes a horizontal bar, said drop bar has a roller disposed in the path of travel of one end of said horizonal bar, when the door is in its closed position and the drop bar is in its lower position, said roller being disposed in the path of travel of the other end of the horizontal bar when the door is in its fully open position and the drop bar is in its lower position, the spring of the stop means, which limit movement of the trolley to the closed position of the door, displaces the trolley a distance sufficient to dispose the horizontal bar beneath the drop bar roller, when the drop bar is raised to release the door from its locked condition in the door closed position, and the spring of the stop means, which limit movement of the trolley to the open position of the door, displaces the trolley a distance sufficient to dispose the horizontal bar beneath the drop bar roller, when the drop bar is raised to release the door from its locked condition in the door open position.

References Cited (Backward Citations)

US3398482A Cited
US3837117A Cited
US4723373A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-04-02 1993-10-02 1994-04-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-04-02 1997-10-02 1998-04-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-04-02 2001-10-02 2002-04-03 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag