GLASS-BREAK SHOCK SENSOR WITH VALIDATION

• US 20100283607A1
• Filed: 11/14/2007
• Published: 11/11/2010
• Est. Priority Date: 11/14/2007
• Status: Active Grant

• Current Assignee: Ademco Inc. (Resideo Technologies, Inc.)
• Original Assignee: Honeywell International Inc.
• Inventors: Smith, Richard A., Petek, Tom R.
• Granted Patent: US 8,144,010 B2
• Time in Patent Office: Days
• US Class Current: 340/541
• CPC Class Codes: G08B 13/04 by breaking of glass
• CPC Class Codes: G08B 13/189 using passive radiation detection systems
• CPC Class Codes: G08B 29/183 Single detectors using dual technologies G08B13/1672, G08B13/2448, G08B13/2494 take precedence

Abstract

An intrusion detector and method for detecting both the breaking of a glass in a window or a door and motion within a protected area. The detector comprises a single sensing section for detecting mechanical impact in a form of an acoustic signal on the window or glass and for detecting motion in a form of a motion induced signal within a protected area, a lens for focusing the motion induced signal, a first filter for filtering out a portion of the motion induced signal which is not in a preset frequency band, a second filter for attenuation a portion of the acoustic signal outside a second preset frequency band, a microprocessor for determining if the detected acoustic signal is consistent with that required to break glass and if the detected motion induced signal is indicative of motion with the protected area, and an alarm generating section for generating an alarm based upon the determination of the microprocessor.

Claims

1. An intrusion detector for a security system that detects the breaking of a glass in a window or a door and motion within a protected area comprising:

a single sensing section for detecting mechanical impact in a form of an acoustic signal on the window or glass and for detecting motion in a form of a motion induced signal within a protected area;

a lens for focusing the motion induced signal;

a first filter for filtering out a portion of the motion-induced signal which is not in a preset frequency band;

a second filter for attenuating a portion of the acoustic signal outside a second preset frequency band;

a microprocessor for determining if the detected acoustic signal is consistent with that required to break glass and if the detected motion induced signal is indicative of motion with the protected area; and

an alarm generating section for generating an alarm based upon the determination of the microprocessor.

2. The intrusion detector of claim 1, wherein said single sensing section comprising a pyre-electric sensor.

3. The intrusion detector of claim 1, wherein said lens confines the detection of the motion induced signal to an area proximate to the window or door.

4. The intrusion detector of claim 3, wherein said area covers an interior surface of the window or door.

5. The intrusion detector of claim 1, wherein said single sensing section changes electrical properties based upon the detected motion induced signal and acoustic signal.

6. The intrusion detector of claim 1, wherein said microprocessor comprises an activation section for activating a motion detection section for a preset period of time, and timing section for timing the preset period of time and wherein the motion processing section ignores the motion induced signal when the motion detection signal is not activated.

7. The intrusion detector of claim 1, wherein said alarm is only generated if the acoustic signal is indicative of an impact and the activated motion detection section determines that the motion induced signal is indicative of motion.

8. The intrusion detector of claim 1, further comprising a transmitter for transmitting a signal to a security system control panel when said alarm is generated.

9. The intrusion detector of claim 8, wherein said signal is a wireless signal.

10. The intrusion detector of claim 5, wherein the motion induced signal is an infrared signal.

11. A method for detecting intrusion in a protected premises comprising the steps of:

detecting a first change in electrical properties of a sensing element;

determining a cause of the first change in the electrical properties;

activating a motion processing section if the cause of the first change is a physical impact that is consistent with that required to break glass;

setting a preset detection time for said motion detection;

determining if a second change in electrical properties is detected within the preset detection time;

determining if the second change in electrical properties is indicative of motion if the change is within the preset detection time; and

generating an alarm only if it is determined that the first change is caused by a physical impact that is consistent with that required to break glass and the second change is caused by motion within the protected area within the preset detection time.

12. The method for detecting intrusion according to claim 11, further comprising the steps of:

determining if the second change in electrical properties is indicative of an impact; and

resetting a timer to the preset detection time based on the determining step.

13. The method for detecting intrusion according to claim 11, wherein said second change in electrical properties is not processed for motion if the second change in electrical properties is not within the preset detection time.

14. The method for detecting intrusion according to claim 11, further comprising the step of transmitting a signal to a control panel.

15. The method for detecting intrusion according to claim 11, wherein said step of determining a cause of first change in the electrical properties includes the sub-steps of:

amplifying the first change in the electrical properties;

filtering the first change in the electrical properties to generated a filtered signal; and

determining the filtered signal based upon a rate of change and amplitude.