Selectively positional intruder alarm for sliding windows and doors

• US 6,388,572 B1
• Filed: 06/18/2001
• Issued: 05/14/2002
• Est. Priority Date: 06/18/2001
• Status: Expired due to Fees

• Current Assignee: Annie L. Salter
• Original Assignee: Annie L. Salter
• Inventors: Salter, Annie L.
• Primary Examiner(s): Wu, Daniel J.
• Assistant Examiner(s): Previl, Daniel
• Application Number:
  US09/883,052
• Time in Patent Office: 330 Days
• Field of Search: 340/546, 340/545.1, 340/541, 340/542, 340/543, 340/545.7, 340/545.8, 340/545.9, 340/547, 340/545.2, 340/693.5, 340/527, 340/528, 340/689, 340/686.1, 200/61.93
• US Class Current: 340/546
• CPC Class Codes: E05B 45/06 Electric alarm locks E05B45/005 takes precedence
• CPC Class Codes: E05B 65/0888 Locking bars
• CPC Class Codes: G08B 13/08 by opening, e.g. of door, of window, of drawer, of shutter, of curtain, of blind

Abstract

A portable selectively positional intruder alarm for sliding windows and doors is installed in a window or door frame with its longitudinal axis parallel to a sliding window sash or door at a selected distance therefrom to provide security while allowing the window to be partially open for ventilation and will emit an alarm either when the window or door is opened further or when the device is removed from the window or door frame. The device has a telescoping tubular housing with end plugs at each end. One end plug is fixed to the housing and the other is slidably mounted in the end of the housing. The end plugs are removably held against the opposed tracks of the sliding window sash or sliding door by the force of a compression spring within the housing. An alarm circuit disposed in the outer tube includes a battery, an audio transducer, a normally-open switch, a normally-closed switch, and may also include a visual alarm and battery condition indicator. An actuator pin on the movable frame surface of the sliding window sash or door engages the normally-open switch upon movement of the frame surface a distance toward the housing such that the partially open or fully closed window sash or door may be opened a distance less than the selected distance for ventilation without sounding the alarm and, upon further opening the window sash or door a distance approximate to the selected distance, the alarm is activated. The sliding end plug is engaged with the normally-closed switch when the device is installed in the track and, when the device is removed, is disengaged to activate the alarm.

Claims

1. A selectively positional alarm device for sliding windows and doors, comprising:

an elongate telescoping tubular housing having a longitudinal axis and including a hollow outer tube having a first end and a second end, and an inner tube having a first end and a second end, said first end of said inner tube being slidably received in said first end of said outer tube, said second end of said inner tube extending from said first end of said outer tube;

a first end plug fixed to said second end of said inner tube, and a second end plug slidably mounted in said second end of said outer tube, each said plug having an outer end sized and shaped to be received in a track of a sliding window sash or sliding door;

a compression spring disposed within said outer and inner tubes to urge them into an opposed extended position such that said end plugs are removably held against said track only by the force of said compression spring;

an alarm circuit disposed in said outer tube including a battery, an audio transducer electrically connected with said battery, and a normally-open switch located in said outer tube having normally-open contacts connected between said audio transducer and said battery;

said tubular housing positioned a selected distance from a frame surface of said sliding window sash or sliding door in either a partially open position or fully closed position with its said longitudinal axis parallel to the plane of said frame surface; and

actuator means disposed between the frame surface of said sliding window sash or sliding door and said normally-open switch to close said contacts and connect said battery with said audio transducer upon movement of said frame surface a distance toward said housing such that said partially open or fully closed sliding window sash or sliding door may be opened a distance less than said selected distance for ventilation without sounding the audible alarm, and upon further opening said window sash or door a distance approximate to said selected distance said audio transducer sounds an audible alarm.

2. The alarm device according to claim 1, wherein

said alarm circuit further includes a depressible switch located in said outer tube near said outer tube second end having normally-closed contacts electrically connected between said battery and said audio transducer; and

said second end plug is slidably mounted in said second end of said outer tube in a loose fashion allowing it to slide relative to said second end of said outer tube between an innermost position when housing is installed and said end plugs are removably held against said track by the force of said compression spring and an outermost position when said end plugs are removed from said track;

in said innermost position said second end plug being engaged with said depressible switch to maintain its said normally-closed contacts in an open condition to prevent activation of said audio transducer; and

in said outermost position said second end plug being spaced from said depressible switch to allow its said normally-closed contacts to close and connect said battery with said audio transducer and sound an audible alarm when said end plugs are removed from said track.

3. The alarm device according to claim 2, further comprising:

a spring-biased button connected with said second end plug and urged laterally outward to extend through a longitudinal slot in said outer tube to allow axial movement of said second end plug relative to said outer tube between said innermost and said outermost positions, and said button being pressed laterally inward toward the interior of said outer tube to allow removal of said second end cap from said outer tube.

4. The alarm device according to claim 1, further comprising:

a spring-biased button connected with said inner tube and urged laterally outward to extend through a longitudinal slot in said outer tube to allow axial telescoping movement of said inner tube relative to said outer tube, and said button being pressed laterally inward toward the interior of said outer tube to allow removal of said inner tube from said outer tube.

5. The alarm device according to claim 1, wherein

said actuator means comprises a pin on said frame surface extending perpendicular thereto, said pin being of sufficient length to extend through an aperture in said outer tube and close said contacts of said normally-open switch upon opening said window sash or door a distance approximate to said selected distance.

6. The alarm device according to claim 1, wherein

said alarm circuit further includes an alarm light electrically connected in parallel with said audio transducer and visible from the exterior of said outer tube to provide a visual indication that said sliding window sash or sliding door has been opened a distance approximate to said selected distance.

7. The alarm device according to claim 1, wherein

said alarm circuit further includes a low-voltage detection circuit and battery condition indicator light electrically connected with said battery to visually indicate when said battery voltage has dropped below a predetermined threshold.

8. The alarm device according to claim 1, wherein

said outer tube and said inner tube are each formed of square tubing.