US 3798627 A
A portable alarm device adapted to be removably mounted on the frame of a door opening to signal the opening of a door with respect to the frame. The electrically operated components of the alarm device are connected in a circuit having a normally open switch which includes an operating contact and a movably actuating arm normally spaced from said contact. The device is suitably mounted on the door frame for locating the actuating arm in opposed normally spaced relation to the surface portion of the door whereby the opening movement of the door is operative to move said arm into contacting engaging position with the switch to close the said circuit and sound the alarm.
Description (OCR text may contain errors)
United States Patent [191 Kaufman Mar. 19, 1974 DOOR GUARD AND ALARM 22 Filed: Sept. 15, 1972 21 Appl. No.: 289,577
 US. Cl 340/274, ZOO/61.62, 340/283  Int. Cl. G08b 13/08  Field of Search 340/283, 274, 276; ZOO/61.45, 61.62; 335/205  References Cited UNITED STATES PATENTS 3,176,093 3/1965 Pollak ZOO/61.62 908,918 1/1909 Wells 4 ZOO/61.62 2,802,204 8/1957 Kennelly ZOO/61.45 M 2,953,660 9/1960 Bohn 335/205 2,924,682 2/1960 Winterburn... 335/205 X 3,525,830 3/1967 Hawkins 340/274 X 3,266,029 8/1966 Callahan 340/283 X 3,270,333 8/1966 Barber 340/283 X 2,721,239 10/1955 Kuffer 340/276 X 1,059,007 4/1913 Sharp 340/276 FOREIGN PATENTS 0R APPLICATIONS 152,098 10/ 1920 Great Britain 340/283 Primary Examiner-John W. Caldwell Assistant Examiner-Scott F. Partridge 5 7] ABSTRACT A portable alarm device adapted to be removably mounted on the frame of a door opening to signal the opening of a door with respect to the frame. The electrically operated components of the alarm device are connected in a circuit having a normally open switch which includes an operating contact and a movably actuating arm normally spaced from said contact. The device is suitably mounted on the door frame for 10- cating the actuating arm in opposed normally spaced relation to the surface portion of the door whereby the opening movement of the door is operative to move said arm into contacting engaging position with the switch to close the said circuit and sound the alarm.
3 Claims, 7 Drawing Figures DOOR GUARD AND ALARM BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to burglar alarms and, more specifically, to an improved portable alarm device adapted to be mounted on the frame of a door opening to signal the opening of a door with respect to the frame.
2. Description of the Prior Art Heretofore, it has been proposed to provide burglar alarms adapted to be applied to a door or window and to sound a warning in the event that the door or window is opened while the alarm device is in its operative condition. Illustrative examples of such alarm devices are noted in U.S. Pat. Nos. 2,825,777; 2,866,181; 3,261,010; 3,266,029; 3,270,333 and 3,378,830. While the heretofore known alarm devices apparently perform their respective intended functions, they have not been successively received in the market place for various reasons.
In some instances, the devices were not sufficiently portable so as to be capable of being readily moved from one location to another. For example, the requirement for portability is of extreme practical importance to traveling salesmen who spend many evenings away from home and in different motels. Such salesmen are in need of a small and relatively simple alarm device which can be easily carried with them and removably mounted on the frame of a door opening. The preferred device should be easily detachable from one particular location, without damage to itself or the door frame, and removably mounted at another selected location for repeated use, as desired. The portability feature is also of importance in ones home whereby the preferred device should be capable of being selectively mounted at a particular location depending on ones special requirements and needs at that time, and moved to another location as may be required at a later time.
In other instances, the electrical circuits used to energize the alarm in the heretofore known devices did not adequately provide for the alarm to continue to sound even where the burglar forcibly separates the device from its mounting arrangement upon his entry into the room.
In still other instances, the heretofore known alarm devices were rather complicated to install and operate, and expensive to manufacture. The present invention is directed toward providing an improved portable alarm device which obviates the aforesaid objections in the manner hereinafter described.
SUMMARY OF THE INVENTION The portable alarm device of the present invention includes a bracket member having an attaching portion for removably mounting the same on the frame of a door opening. The bracket further includes a casing thereon housing the electrically operated components of the alarm device. The said electrical components are connected in a circuit having a normally open switch which includes an operating contact and a movably actuating arm normally spaced from said contact and mounted for engaging said contact to close the circuit and energize the alarm. The alarm device is suitably mounted on the door frame for locating the actuating arm in opposed normally spaced relation to a surface portion of the door whereby the opening movement of the door is operative to move said arm into contacting engaging position with the switch to close the said circuit and sound the alarm.
The alarm device of the present invention further provides for the actuating arm to be formed of magnetic material and also includes magnetic means located on the bracket which is operative to retain the actuating arm in its contact engaging position once the circuit has been closed.
Accordingly, an object of the present invention is to provide an improved portable alarm device which is capable of being readily moved from one location to another, as desired, and which will continue to sound the alarm even where the burglar forcibly separates the device from its mounting structure.
Another object and feature of the present invention is to provide an improved portable alarm device that is relatively simple in construction and inexpensive to manufacture.
A further object, feature and advantage of the present invention is to provide an improved portable alarm device which can be easily mounted on the frame of a door without special tools.
The above and other objects, features and advantages of the present invention will become more apparent from the consideration of the following detailed description when taken in conjunction with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front perspective view of the portable alarm device constructed in accordance with the present invention;
FIG. 2 is a rear perspective view thereof;
FIG. 3 is an end elevational view thereof illustrating the device mounted on the frame of a door and in its inoperative condition;
FIG. 4 is a view similar to that of FIG. 3 illustrating the door in a position to operate the device;
FIG. 5 is an end elevational view of the device separated from the frame of the door, yet still in an operative condition;
FIG. 6 is a circuit diagram of the electrical components of the device; and
FIG. 7 is a view similar to that of FIG. 2 illustrating an alternative attaching means for securing the device to the door frame.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, particularly FIGS. 1 and 2, numeral 10 represents a portable alarm device constructed in accordance with the present invention. The alarm device comprises a bracket member 12 preferably formed of rigid plastic or metal which includes an upstanding panel 14 and a depending panel 16 interconnected to each other by means of an intermediate panel 18. Panels l4, l6 and 18 are integrally formed into bracket 12, with panels 14 and 16 disposed in parallel, offset relation to each other for reasons that will be more fully apparent in connection with the description of FIGS. 3 and 4.
Panel 14 includes a pair of laterally spaced hanger openings 20 formed therein for engageably receiving hanger means projecting from the frame of a door for detachably mounting the alarm device thereon. In this connection, panel 14 may be aptly deemed the bracket attaching portion of bracket 12 wherein the manner of mounting said bracket 12 to the door frame is more fully described in connection with the'description of FIGS. 3 and 7.
Panel 16 includes a casing forming member 22 mounted thereon to provide a casing for housing the electrically operated components of the alarm device. Casing forming member 22 includes a front face panel 24, a pair of spaced side panels 26 extending rearwardly from the respective side edges of face panel 24 and a pair of rear flange-like panels 28 extending from the edges of the respective side panels 26 and projecting inwardly toward each other. The structural arrangement is such that rear flange panels 28 are each substantially parallel to face panel 24 and spaced therefrom to define a casing area bounded by the panels 24, 26, 28 and the depending panel 16 of bracket 12. In this connection the rear flange panels 28 may be adhesively bonded to panel 16 to securely mount the casing forming member 22 to said panel 16. Furthermore, the aforesaid structural arrangement issuch that panel 16 may be aptly deemed the casing mounting portion of bracket 12.
As previously indicated, and with reference to FIGS. 1 and 6, the electrically separated components of alarm device 10 are located within the aforesaid casing wherein said components include an audible alarm device 30; such as a horn, bell or the like, a battery 32 and a normally open switch 34 in circuit with said alarm 30 and battery 32 by means of electrical leads or conduc tors 36. Switch 34 includes a contact 38 projecting through an opening in the rear surface of panel 16 and a movable actuating arm 40, formed of magnetic material, having one end 42 fixedly secured to said rear surface of panel 16. The arrangement is such that the free end of arm 40 is normally displaced outwardly away from panel 16 and spaced from contact 38 in overlying relation thereto. The fixed end 42 of arm 40 is also electrically connected to another contact 44 of switch 34. It is thus apparent that the electrical circuit illustrated in FIG. 6 is in a normally open condition and is adapted to be closed when the free end of arm 40 is brought into its contacting engaging position with contact 38 as hereinafter described.
Referring to FIGS. 3 and 4, device 10 is illustrated as being removably mounted on the frame 46 of a door opening by hanger means; such as a screw 48 having a head portion 50. In this connection, openings in the bracket attaching portion of bracket 12 are each formed having an enlarged circular portion 52 adapted to pass the head 50 of screw 48 therethrough and a narrower slotted portion 54 projecting upwardly from the enlarged portion 52 and in communication therewith. The dimensions of the openings 20 are such that the diameter of each enlarged portion 52 is slightly greater than that of screw head 50, and the width of each slotted portion 54 is slightly greater than the diameter of the shank portion of screw 48 but less than the diameter of screw head 50. g
The mounting arrangement is such that "screw 48 is initially fastened to door frame 46 with the head portion 50 thereof slightly spaced therefrom a distance approximately equal to the thickness of panel 14. Bracket 12 is then mounted to door frame 46 by placing plate 14 flat against said frame with screw head 50 passing through enlarged opening 52. Bracket 12 is then slid downwardly whereby the shank portion of screw 48 abuts the upper end of slotted portion 54. The location of openings 20 are such that upon mounting bracket 12 on door frame 46, intermediate panel 18 is located so as to clear the upper edge of door 56 when the said door is opened in the direction of the arrow, as illustrated in FIG. 3.
As previously indicated, the free end of arm 40 is normally spaced from contact 38 and in overlying relation thereto. The aforesaid mounting of bracket 12 is such that the said free end of arm 40 is also located in opposed normally spaced relation to the surface portion of door 56. Accordingly, as the door is opened, the movement thereof in the direction of the arrow is operative to move arm 40 into contact engaging relation with contact 38 to close the electrical circuit and sound the alarm. In this connection, face panel 24 includes a plurality of small openings 58 located adjacent alarm 30 to provide the audible sound to be readily transmitted therethrough and to be heard.
Another feature of the invention provides for arm 40 to be formed of magnetic material and for magnetic means 60 to be located on the rear surface of panel 16 in opposed, normally spaced relation to arm 40. The intermagnetic characteristics of arm 40 and magnetic means 60 is such that after arm 40 is moved into contacting relation with contact 38 by the opening movement of door 56, magnetic means 60 is then operative to retain said arm 40 in its contact engaging position with contact 48. Accordingly, as illustrated in FIG. 5, even where the alarm device is forcibly separated from the door frame, the circuit will remain closed under the influence of the intermagnetic characteristics of arm 40 and magnetic means 60 to continue to sound the alarm. The circuit can be opened to de-energize the alarm only by forcibly separating arm 40 away from contact 38 a distance sufficient to offset the magnetic effect of magnetic means 60 on arm 40.
Still another feature of the invention resides in the mounting arrangement of bracket 12 to door frame 46 whereby said bracket also functions as a guard to materially reduce the likelihood of some unauthorized person entering the room even in those instances where the alarm is not energized. For example, however unlikely the occurrence, it is possible that a short circuit may develop which will prevent the alarm from being energized even after arm 40 is moved into its contact engaging position with contact 38. In such instances, the depending panel 16 and the casing forming member 22 mounted thereon are nonetheless located in opposed contacting relation to a surface portion of door 56 whereby the opening movement of said door is operative to bring said door surface portion into abutting contacting relation to said panel 16, and to stop further opening movement of the door. To this extent, bracket 12 may also be deemed a guard in thwarting attempts at unauthorized entry into the room.
FIG. 7 illustrates another embodiment of the invention which incorporates alternative means for removablyv mounting the bracket 12 to door frame 46. In this embodiment, openings 20 of panel 14 are eliminated and replaced with pressure sensitive adhesive means 62 located on the rear surface of said panel. A removable protective covering 64 is provided in normally overlying relation to said adhesive, and which is removable to expose said adhesive for securing the bracket to the door frame. The use of this mounting arrangement obviates the need for screwing anything into the door frame and thus reduces the likelihood of damaging or marring the finish of said frame. This feature may be of extreme importance where the alarm device is intended to be used in places away from home, where one would not wish to damage or mar the finish of the door frame in someone elses home or in a hotel room.
ln using the embodiment of FIG. 7, one need merely peel off the protective covering 64 and mount panel 14 to frame 46 in the manner and location hereinbefore described. The covering should not be discarded since it is within the purview of the invention to selectively move the alarm device to other locations as desired.
Accordingly, after the alarm device has performed its intended function at one given location, one need only replace the covering 64 to protect adhesive coating 62 until such time as it is necessary to again mount the alarm device at another location, whereupon the aforesaid mounting procedure is repeated.
It is readily apparent that openings of the embodiment of FIG. 1 can be incorporated in the structure of embodiment of FIG. 7 wherein panel 14 would then include the said openings 20 together with the adhesive means 62 and protective covering 64. ln such event, protective covering 64 would be provided with openings similar to the openings 20 on panel 14 and in registry therewith. This structure would permit a choice as to the manner in which bracket 12 is mounted on door frame 46.
It is further readily apparent that the present invention overcomes many of the drawbacks existing in the heretofore known alarm devices. The present device is truly portable and capable of repeated use at selected locations, as desired. The mounting procedure is relatively simple and, at least with respect to the embodiment of FIG. 7, does not require any tools whatsoever.
While specific embodiments of the invention have been shown and described in detail, it will be readily understood and appreciated that various changes or modifications thereof may be made without departing from the spirit and scope of the invention as set forth in the appended claims.
1. A completely self-contained portable alarm device adapted to be mounted on a building portion closely adjacent to a door and off-set from a door opening, said device comprising a bracket member having a vertically disposed attaching portion adapted to be readily removably attached to said building portion, a lateral portion extending orthogonally from said attaching portion, a panel member depending from said laterally extending portion and extending in a generally parallel relationship but in a direction opposite to said attaching portion, said panel member having an opening formed therein, a casing mounted on said depending panel portion, electrically operated alarm means located within said casing, said alarm means including an audible alarm device, a battery and a normally opened switch in circuit with said audible alarm device and battery, said switch including an operating contact projecting through said opening in said panel member, a movable actuating arm on said panel member for engaging said operating contact of said switch to close said circuit, said arm being formed of magnetic material and being normally disposed out of contact with said switch, magnetic means on said panel member in juxtaposition to said contact receiving opening and retaining said arm when moved there against in its switch contact engaging position, said bracket attaching portion including means for detachably mounting the alarm device on the door frame to be normally spaced from the door when in closed position and off-set from said door opening juxtaposed in normally spaced relationship to a surface portion of the door but in a position to be contacted by said door when opened whereby the opening movement of the door is operative to move said arm to engage said switch contact to close the circuit and to be held by said magnetic means.
securement to said door frame.