Door Security Device Allowing Partial Door Opening

The present invention relates generally to door security devices, and particularly to door security devices allowing partial opening of a door while maintaining protection against forced entry.

Residential door security is essential. Every residence has locking doors barring unauthorized entry, especially forced entry. The greater protection against forced entry, the greater the security enjoyed by the inhabitants. Extra security devices, beyond a latch set and dead bolt, are often used once the occupants are inside the building. Such devices are not accessible from the outside and, therefore, are less vulnerable to compromise from the outside. In many situations it is desirable to allow partial opening of the door, but retain protection against forced entry. Door chains selectively couple the door to the surrounding frame to allow partial opening of the door while maintaining some degree of security. Door chains, however, lack good security because of the typically weak attachment of the chain components to the door and surrounding door frame. Once the door is open, the chain itself can be easily broken, or can be broken away from the door or from the door frame.

A door security device under the present invention includes a pivot support mounted adjacent a door and defining an axis of rotation. A pivot bar includes a first length portion pivotally supported by the pivot support and a second length portion in spaced relation to the first length portion. As the door begins to open, the second length portion engages the door and causes the device to pivot about its axis of rotation. Eventually, the device blocks further opening of the door, but maintains a high degree of security against forced entry. In a preferred embodiment of the present invention, the first length portion is mounted vertically near a door threshold and the second length portion assumes an upstanding orientation to engage the bottom edge of the door. By coupling the door to the relatively more fortified floor structure, as compared to a surrounding frame structure, the device of the present invention improves door security. In a second mode of operation, the security device may be used to pin the door shut in its closed position without allowing partial opening of the door.

The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation of the invention, together with further advantages and objects thereof, may best be understood by reference to the following description taken with the accompanying drawings wherein like reference characters refer to like elements.

For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings in which:

FIG. 1 is a perspective view of a doorway including a door security device according to a preferred embodiment of the present invention.

FIG. 2 illustrates separately a door bar of the door security device of FIG. 1.

FIG. 3 is a top sectional view of the doorway and door security device of FIG. 1 as taken along lines 3--3 of FIG. 1.

FIG. 4 is a face view detailing the doorway and door security device of FIG. 1.

FIG. 5 is a top sectional view similar to FIG. 3, but showing operation of the door security device of FIG. 1 allowing secure partial opening of the doorway.

FIG. 6 is a face view of the door security device of FIG. 1 in an alternative mode of operation pinning the door in a closed position.

The present invention provides a door security device placed in operation from the inside and generally intended as a supplement to ordinary door security devices such as latch sets and dead bolts. The device finds advantage in its ease of installation and use, low cost, and effective security against forced entry.

FIG. 1 illustrates a preferred embodiment of the present invention, a door bar 10 securing a conventional doorway 12. Doorway 12 includes a door 14 resting upon hinges 16 within a door frame 18. Door 14 carries a conventional locking entry latch set 20 and dead bolt 22 securing door 14 in its closed position within door frame 18. Latch set 20 and dead bolt 22 secure door 14 to the frame 18 to the extent that hinges 16, latch set 20 and dead bolt 22 are secured to the frame 18. Frame 18 includes a threshold 24 defining a vertical separation 26 between the lower edge 14a of door 14 and a floor 28, specifically floor surface 28a, on the inner side 18a of frame 18. Door 14 is secured in its fully closed position so long as latch set 20 and dead bolt 22 remain engaged in frame 18. Once latch set 20 and dead bolt 18 are unlocked, however, door 14 can pivot on hinges 16 away from its fully closed position.

The door bar 10 couples door 14 to floor 28 and holds door 14 against pivoting open. In a first mode of use (FIGS. 1 and 3-5), door bar 10 allows partial opening of door 14 following release of latch set 20 and dead bolt 22. More particularly, door bar 10 allows door 14 to open several inches, but maintains coupling between door 14 and floor 28. As may be appreciated, floor 28 is better suited to resist forced entry than frame 18. Coupling door 14 to the better fortified floor 28 thereby enhances protection against forced entry through doorway 12.

FIG. 2 illustrates the door bar 10 separately from the doorway 12. In FIG. 2, door bar 10 includes a first length portion 10a and a second length portion 10b. Length portions 10a and 10b are in spaced, parallel relation and rigidly interconnected by coupling length portion 10c. In the preferred embodiment of the present invention, portion 10c is perpendicular to portions 10a and 10b. Door bar 10 may be constructed from a variety of materials, but preferably of a unitary body of rigid material capable of resisting deformation.

Returning to FIG. 1, door bar 10 rests pivotally within a support collar 10d buried in floor 28 below surface 28a. Collar 10d may be secured to floor 28 by first drilling a hole corresponding in depth to the length of collar 10d. The inner diameter of collar 10d closely matches the outer diameter of length portion 10a to allow free pivoting of length portion 10a within collar 10d. In such pivotal mounting to the floor 28, the length portion 10c moves within a horizontal plane immediately adjacent surface 28a of floor 28. The length portion 10b assumes a vertical orientation above floor surface 28a and orbits about the axis of rotation defined by collar 10d. The vertical dimension of length portion 10c is less than the vertical separation 26 between lower edge 14a of door 14 and floor surface 28a to allow partial opening of door 14, i.e., allow door 14 to pass over the horizontally disposed length portion 10c. With the collar 10d positioned immediately inside the threshold 24, however, the length portion 10b blocks full opening of the door 14.

In FIG. 3, door 14 is shown moving slightly from its closed position 40. It is assumed that latch set 20 and dead bolt 22 have been released and door 14 is just beginning to open. Door 14 immediately passes over length portion 10a and collar 10d. As shown in FIG. 4, the vertical separation 26 between lower edge 14a of door 14 and floor surface 28a is sufficient to accommodate the length portion 10c of door bar 10. As door 14 continues to open, it engages the upstanding length portion 10b and causes door bar 10 to pivot within the collar 10d until such time that door 14 reaches the position shown in FIG. 5, i.e., when the length portion 10c becomes normal to the plane of door 14. Further urging of door 14 towards an opened position is blocked by door bar 10. As may be appreciated, while the door bar 10 may be visible to a person on the outside of door 14 as indicated in FIG. 5, door bar 10 is captured within collar 10d by virtue of the positioning of door 14 over the length portion 10c. In other words, it would be impossible for an intruder to disable the door security device 10 even with door 14 open as shown in FIG. 5.

In a second mode of use, door bar 10 augments security provided by latch set 20 and dead bolt 22 by preventing door 14 from moving beyond its closed position. In FIG. 6, door bar 10 is shown in its second mode of use. The length portion 10b is inserted within collar 10d. Because length portion 10b is longer than the combined vertical separation 26 and depth of collar 10d, length portion 10b extends vertically above the lower edge 14a of door 14. Accordingly, door bar 10 in this mode of use pins shut door 14 in its closed position. Door bar 10 thereby augments security provided by latch set 20 and dead bolt 22 in their locked positions. As may be appreciated, coupling door 14 to floor 28 in the manner illustrated in FIG. 6 can only improve resistance against forced entry.

Door security device 10 may further include a bracket 50 providing a generally rectangular space between itself and door 14 in the vicinity of collar 10d when door 14 is shut. The bracket 50 may be attached directly to the door 14. Bracket 50 maintains door bar 10 against door 14. This keeps door bar 10 from inadvertently pivoting away from door 14 in its closed position and presenting risk of injury to persons. For example, a person could either trip on door bar 10 or fall upon door bar 10 with resulting injury. Thus, in the first mode of use, bracket 50 maintains the upstanding portion 10b adjacent the door 14. In the second mode of use, bracket 50 captures portion 10c against door 14 and prevents any pivoting of door bar 10. By appropriate dimensioning of the portions 10a-10c and vertical positioning of bracket 50, the portion 10c lies within the rectangular space of bracket 50 in the second mode of use. As may be appreciated, the bracket 50 does not necessarily enhance the security provided by door bar 10, rather is provided primarily as an alternative or optional safety feature. It is contemplated, however, that should the door bar 10 begin to bend under forced entry of door 14, the bracket 50 would aid in resisting further bending of door bar 10.

The preferred form of the present invention provides a stainless steel door bar 10 constructed by bending of 7/16 inch diameter round stock with portion 10a of 21/4 inches length, portion 10b of 5 inches length, and portion 10c of 4 inches length. The depth or length of collar 10d is selected to accommodate full insertion of the length portion 10a within collar 10d, but not full insertion of length portion 10b, in the preferred embodiment collar 10d provides a depth of 21/2 inches. The angular relationship between length portion 10a and length portion 10c is preferably as close as possible to perpendicular. This allows the length portion 10c to move in a horizontal plane closely above the surface 28a of floor 28 and within the vertical separation 26.

In overall operation, door bar is used from the inside of door 14. When operated in its first mode of use allowing partial, but secure, opening of door 14 the length portion 10a is inserted into collar 10d. It is contemplated that latch set 20 and dead bolt 22 remain in their locked positions. If a visitor comes to doorway 12 and the occupant wishes to view the visitor or exchange a package with the visitor, the latch set 20 and dead bolt 22 may be released and door 14 partially opened while maintaining a coupling between door 14 and floor 28, i.e., blocking door 14 against full opening by use of door bar 10. As may be appreciated, the occupant can leave door bar 10 in its second mode of use, pinning door 14 in its shut position, but switch to the first mode of use prior to unlocking the latch set 20 and dead bolt 22 when secure partial opening of door 14 is desired. In its second mode of use, door bar 10 pins door 14 in its shut position to enhance the security provided by door 14. It is contemplated that pinning the door 14 in this manner to the more substantial floor 28 provides a more secure doorway. A floor structure can be substantially more fortified relative to a door frame. For example, floor 28 may include more substantial material, i.e., larger dimensioned and interconnected wood elements, or more substantial material such as concrete. To the extent that collar 10d may be better fortified within the floor 28, enhanced security is provided by the door bar 10.

Thus, a door security device allowing partial door opening has been shown and described. The device is simple to use, yet provides significant security features. It is contemplated that the invention may be provided as a kit consisting of the collar 10d, door bar 10, and bracket 50. Purchasers of the kit need only drill a hole in a floor adjacent a doorway to be secured and insert the collar 10d. The bracket 50 may then be secured to the doorway in appropriate position and installation is complete. The user switches between the first and second modes of use by merely removing and reorienting door bar 10 according to the selected mode. To fully open the door, the user simply removes door bar 10 from collar 10d.

It will be appreciated that the present invention is not restricted to the particular embodiment that has been described and illustrated, and that variations may be made therein without departing from the scope of the invention as found in the appended claims and equivalents thereof.