Miscellaneous hardware (e.g. – bushing – carpet fastener – caster – Closure checks – Spring
Reexamination Certificate
1999-11-16
2001-11-27
Browne, Lynne H. (Department: 3629)
Miscellaneous hardware (e.g., bushing, carpet fastener, caster,
Closure checks
Spring
C016S08600R, C292SDIG001
Reexamination Certificate
active
06321412
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to devices for absorbing and dissipating forces generated by swinging doors and for protecting walls and partitions of buildings. The novel device is installed in a wall or partition in a location assuring that a door knob of a door will strike the novel device when the door is swung open with force. The invention is usable both in new construction and in retrofit applications for most residential, commercial, industrial, and institutional buildings wherein doors are not restrained and could damage either themselves or a wall or partition in the way if swung open with excessive force. The invention is particularly suited for repairs of walls and partitions built from drywall, wherein prior contact of a door knob with the drywall has formed a depression or hole therein.
2. Description of the Prior Art
Most doors in residential, commercial, industrial, and institutional buildings are mounted so as to be able to swing about a vertical axis. When the door is opened, if no apparatus is provided to limit swing of the door, the full momentum of the door may be imposed on a wall or partition where the door knob strikes that wall or partition. This will obviously damage the wall, the door, or both. This is a notoriously well known problem which has resulted in prior art attempts to solve the problem.
One approach has been to mount a receptacle within the wall or partition. This approach is seen in U.S. Pat. No. 3,133,758, issued to Malcolm B. Wells on May 16, 1964. The receptacle of Wells lacks a coil spring disposed to resist momentum of the door and a pneumatic damping chamber, both seen in the present invention. Also, Wells lacks a brace which abuts the side of a hollow wall opposite that in which the novel door knob stop is mounted.
U.S. Pat. No. 5,722,115, issued to Richard Arens on Mar. 3, 1998, is similar to the device of Wells, and also lacks the coil spring, pneumatic damping chamber, and brace of the present invention.
U.S. Design Pat. No. 324,170, issued to R. Larry Owens et al. illustrates a combined door stop and wall patch which lacks the coil spring, pneumatic damping chamber, and brace of the present invention.
A second approach is to provide a door stop which projects from the wall. This is seen in U.S. Pat. No. 5,761,766, issued to William E. Basham on Jun. 9, 1998. The door stop of Basham lacks a pneumatic damping chamber and a flush mounting flange, both being features of the present invention. The door stop of Basham lacks the brace of the present invention.
Another device generally corresponding to a door stop is shown in U.S. Pat. No. 5,806,908, issued to Yong Pyo Kim on Sep. 15, 1998. This device requires one component mounted on one of the members which collide and a second component mounted on the other one of the colliding members. By contrast, the present invention requires only one component. Also, the devices of Kim are surface mounted, whereas the present invention has a flange for flush mounting in a wall. A further difference is that a resilient solid member absorbs energy in the device of Kim, whereas this is accomplished by a pneumatic damper in the present invention. Neither component of Kim's device contacts two supporting surfaces, as do the mounting flange and brace of in the present invention.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.
SUMMARY OF THE INVENTION
The present invention provides a door stop which dissipates the momentum of a swung door and which is readily installed in a hollow door typical of walls and partitions built from drywall sheets mounted on studs. Hereinafter, such walls and partitions will be called walls. In particular, the invention is readily installed in a wall after a hole has been formed by a collision between the door knob and the wall.
Structure of the present invention includes an annular housing having an outwardly projecting flange for covering the outer surface of the wall being protected. The flange performs several functions. One function is to provide a supporting surface distributing force of impact over the front surface of the wall. A second function is aesthetic, in that the flange conceals potentially objectionable damage which may be present in drywall from prior impacts. A third function is to limit penetration of the annular housing of the door stop into the wall. A fourth function is to form the walls of a chamber which develops pneumatic pressure when dissipating force of impact of the door being protected.
A second supporting member is provided by a brace fixed to the concealed end of the door stop. This brace abuts the interior or concealed surface of drywall material of the other side of the wall. Forces imposed on the door stop are therefore borne by two different panels of drywall, thereby reducing maximum loads imposed on any one panel of drywall. This is significant since drywall has much less strength than other building materials employed for walls.
The novel door stop absorbs and cushions forces from a swung door by a spring and also pneumatically. The spring stores forces, converting a negligible amount of kinetic energy into heat. By contrast, the pneumatic feature is very important in dissipating energy from the door and door stop. It is double acting, in that it resists rapid movement of a piston occupying the pneumatic pressure chamber of the door stop as a swung door collides with the door stop, and also resists unrestrained, rapid rebound of the piston during the return stroke. Dissipation of energy is thus spread out over time, which is an important principle in countering damage from rapid or violent collisions.
The present invention is suitable for repairs of damaged walls since it is readily installed through a hole left following a collision between the door knob and wall. The flange conceals damage, if minor, which would otherwise be aesthetically objectionable, and which would impair strength of the wall. The novel door stop imparts a finished appearance to a wall with remarkably little labor of repair. It is relatively inconspicuous since it is virtually flush with the finished wall.
Accordingly, it is one object of the invention to provide a door stop which dissipates energy of a swung door.
It is another object of the invention that the door stop conceal minor damage to the wall.
It is a further object of the invention that the door stop distribute force of impacts over both the damaged drywall panel of the wall and also over the opposed drywall panel of the wall.
Still another object of the invention is that the door stop be flush with the wall.
An additional object of the invention is that the door stop be readily installed in a wall.
It is again an object of the invention to be suitable for repairing walls damaged by impacts from door handles.
Yet another object of the invention is to impose minimal aesthetic impact on walls provided with door stops.
It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.
REFERENCES:
patent: D. 324170 (1992-02-01), Owens et al.
patent: 1211480 (1917-01-01), Newton
patent: 1514845 (1924-11-01), Fischer
patent: 2479597 (1949-08-01), Anton
patent: 3133758 (1964-05-01), Wells
patent: 4462623 (1984-07-01), Grant
patent: 5722115 (1998-03-01), Arens
patent: 5761766 (1998-06-01), Basham
patent: 5806908 (1998-09-01), Kim
Browne Lynne H.
Hingham John R. C.
Siemens Patent Services LC
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