Portable, gravity-actuated alarm for use with a window or door

Claim 2

In an intrusion alarm device for a door or window comprising: a lever for engagement with a door or window when the latter is closed, means pivotally mounting said lever to drop down by gravity when the door or window is opened; a magnetic switch having a permanent magnet on said lever and magnetically-operated switch means mounted in spaced relationship to said mounting means for the lever for operation by said magnet when the lever drops down; and signalling means operable to signal an alarm when said switch means is operated; the improvement wherein said switch means is positioned to one side of the path of movement of said lever when the latter drops down and is in close proximity to said magnet when the lever is down.

Claim 3

In an intrusion alarm device for a door or window comprising: a lever for engagement with a door or window when the latter is closed, means pivotally mounting said lever to drop down by gravity when the door or window is opened, a weight attached to said lever to pull the lever down when the door or window is opened; a magnetic switch having a permanent magnet on said lever and magnetically-operated switch means mounted in spaced relationship to said mounting means for the lever for operation by said magnet when the lever drops down; and signalling means operable to signal an alarm when said switch means is operated; the improvement wherein said weight is offset from said lever in a direction to pull the lever down by gravity when the door or window is opened.

Claim 4

In an intrusion alarm device for a door or window comprising: a lever for engagement with a door or window when the latter is closed, means pivotally mounting said lever to drop down by gravity when the door or window is opened, a weight attached to said lever to pull the lever down when the door or window is opened; a magnetic switch having a permanent magnet on said lever and magnetically-operated switch means mounted in spaced relationship to said mounting means for the lever for operation by said magnet when the lever drops down; and signalling means operable to signal an alarm when said switch means is operated; the improvement wherein said weight is offset from said lever in a direction to pull the lever down by gravity when the door or window is opened.

Claim 5

An alarm device according to claim 2, and further comprising a rod attached at one end to said lever away from the latter's pivotal mounting, said weight being attached to the opposite end of said rod.

Claim 6

An alarm device according to claim 3, wherein said rod is threadedly engaged on at least one end for adjustment of its effective length between said lever and said weight.

Claim 7

An intrusion alarm device for a door or window comprising: a lever for engagement with a door or window when the latter is closed, means pivotally mounting said lever to drop down by gravity when the door or window is opened; a magnetic switch having a permanent magnet on said lever and magnetically-operated switch means mounted in spaced relationship to said mounting means for the lever for operation by said magnet when the lever drops down; and signalling means operable to signal an alarm when said switch means is operated; the improvement which comprises a casing having peripheral sides, and wherein: said means pivotally mounting the lever comprises a bracket inside the casing; said lever in its raised position extends up past the edge of one side of the casing and outside the casing for engagement of its outer free end with the door or window; and said lever when it drops down moves into the casing.

Claim 8

An intrusion alarm device for a door or window comprising: a lever for engagement with a door or window when the latter is closed, means pivotally mounting said lever to drop down by gravity when the door or window is opened; a magnetic switch having a permanent magnet on said lever and magnetically-operated switch means mounted in spaced relationship to said mounting means for the lever for operation by said magnet when the lever drops down; and signalling means operable to signal an alarm when said switch means is operated; the improvement which comprises a casing having peripheral sides, and wherein: said means pivotally mounting the lever comprises a bracket inside the casing; said lever in its raised position extends up past the edge of one side of the casing and outside the casing for engagement of its outer free end with the door or window; and said lever when it drops down moves into the casing.

Claim 9

An alarm device according to claim 5, wherein said switch means is positioned inside the casing to one side of the path of travel of said lever when the latter drops down into the casing and is closely spaced from said magnet when the lever is down.

Claim 10

An alarm device according to claim 6, and further comprising a weight attached to the lever between its pivot and its outer free end, and means for offsetting said weight from the lever for pulling the lever by gravity down into the casing when the door or window is opened.

Claim 11

An intrusion alarm device comprising: a casing having a bottom wall, upstanding interconnected side walls, and a hinged cover; a generally L-shaped bracket inside said casing having a leg which extends substantially parallel to a side wall of the casing; magnetically-operated switch means attached to said side wall and projecting therefrom into the casing; a lever pivoted at one end to said bracket leg and extending therefrom substantially parallel to said one side wall of the casing and beyond an adjoining side wall for engagement at its opposite end with a door or window; a permanent magnet attached to said lever on the side toward said one side wall of the casing, said magnet moving with said lever into close proximity to said switch means for closing said switch means magnetically when the lever drops down pivotally from engagement with the door or window; and signalling means in said casing connected electrically to said switch means for signalling an alarm when said switch means closes.

Claim 12

An intrusion alarm device comprising: a casing having a bottom wall, upstanding interconnected side walls, and a hinged cover; a generally L-shaped bracket inside said casing having a leg which extends substantially parallel to a side wall of the casing; magnetically-operated switch means attached to said side wall and projecting therefrom into the casing; a lever pivoted at one end to said bracket leg and extending therefrom substantially parallel to said one side wall of the casing and beyond an adjoining side wall for engagement at its opposite end with a door or window; a permanent magnet attached to said lever on the side toward said one side wall of the casing, said magnet moving with said lever into close proximity to said switch means for closing said switch means magnetically when the lever drops down pivotally from engagement with the door or window; and signalling means in said casing connected electrically to said switch means for signalling an alarm when said switch means closes.

Claim 13

An alarm device according to claim 8 wherein said signalling means comprises a battery and a battery-operated sounding device inside said casing, and a manually-operated on-off switch in said casing connected in series with said magnetically-operated switch means and said sounding device across said battery.

Claim 14

An alarm device according to claim 8, and further comprising a weight attached to the lever between its pivot and said opposite end, and means for offsetting said weight from the lever for pulling the lever by gravity down into the casing when the door or window is opened.

Claim 15

An alarm device according to claim 10, wherein said last-mentioned means comprises a rod attached at one end to said lever between the latter's ends, said weight being attached to the opposite end of said lever.

Claim 16

An alarm device according to claim 10, wherein said lever has an extension pivoted to said opposite end, and means for releasably holding said extension retracted alongside the lever.

Claim 17

An alarm device according to claim 8, and further comprising cord-guiding members attached to the inside of certain of said side walls of the casing for slidably passing a pull cord for the lever.