The present invention relates to alarm systems, and more particularly to alarm systems including identification modules which enable analog-type measurements.
The present invention also relates to single-wire loop alarm systems which enable use of both digital devices such as switches to detect conditions which trigger the alarm as well as analog sensors which can also detect other types of conditions which trigger the alarm.
Alarm systems are known which include a number of switches each connected to an identification module and through common wires to a controller. The controller is capable of determining which switches are tripped or malfunctioning by obtaining identification data from the identification module associated with any tripped or malfunctioning switches.
It would be desirable to provide a single-wire loop alarm system which is capable of processing analog input.
It is an object of the present invention to provide new and improved alarm systems, specifically single-wire loop alarm systems.
It is another object of the present invention to provide new and improved identification modules, in particular for a single-wire loop alarm system.
In order to achieve at least one of these objects and possibly others, one embodiment of an alarm system in accordance with the invention includes a controller, a single-wire loop connected to the controller, a plurality of identification modules connected to the single-wire loop and various attachments to or incorporated structures on or in the identification modules. Some attachments or incorporated structures include digital devices such as on/off switches and loads while other attachments are analog devices. Each identification module is programmed to provide a signal or report to the controller indicative of whether the associated device (digital or analog) is in a normal state, i.e., a normal signal, or an alarm/trouble state, i.e., an alarm signal which also serves as a fault signal.
When analog devices are used, the identification modules are preferably designed not only to convert the analog readings from the analog devices to digital form but also to provide for a permitted range of variation in the sensor readings so that not all variations from a single, predetermined value of the condition being monitored by the sensor are considered indicative of a problem with the area(s) being monitored by the sensor or a fault with the sensor. The analog devices may be resistive-type temperature or pressure sensors, sensors which output a voltage or switches arranged in a current loop.
In one embodiment, the devices are motion detectors and the identification modules determine the condition of the motion detectors and report to the controller if the motion detectors are in a normal state, i.e., motion has not been detected, or if the motion detectors are in an alarm/trouble state, i.e., motion has been detected. The determination of the detection of motion may be relative to a threshold so that lack of motion or motion below the threshold is considered a normal state which would cause generation of a normal signal to be provided to the controller and only motion above a threshold is considered an alarm/trouble state which would cause generation of an alarm signal to be provided to the controller.
A combined analog and digital alarm system in accordance with the invention includes a controller, a single-wire loop connected to the controller, and one or more module assemblies connected to the single-wire loop, each including a sensor arranged to generate a non-digital signal representative of a condition in an area being monitored by the sensor and an identification module arranged to convert the non-digital signal into digital form, analyze the converted signal and generate and provide a signal to the controller relating to whether the condition being monitored by the sensor is normal or indicative of a fault with the sensor or an alarm state. The identification module analyzes the converted signal by determining variation of the condition being monitored by the sensor from a permitted range of values, whereby variation within the permitted range causes generation of a normal signal and variation outside of the permitted range causes generation of an alarm signal. The digital aspect of the alarm system involves the presence of one or more alarm assemblies coupled to the single-wire loop, each of which includes a digital-signal generating device, e.g., a switch or a load, and an identification module arranged to generate and provide a signal to the controller indicative of the status of the digital-signal generating device.
A method for monitoring an area in accordance with the invention includes arranging module assemblies at various locations in the area, each module assembly including a sensor arranged to generate a non-digital signal-representative of a condition in the area being monitored by the sensor and an identification module arranged to convert the non-digital signal into digital form, analyze the converted signal and generate a signal relating to whether the condition being monitored by the sensor is normal or indicative of a fault with the sensor or an alarm state, connecting the identification modules to a single-wire loop, connecting the single-wire loop to a controller, and providing the signals from the identification modules to the controller to enable the controller to determine a fault with any sensor or an alarm state detected by any sensor.
In one embodiment, the identification module analyzes the converted signal by determining variation of the condition being monitored by the sensor from a permitted range of values. Variation within the permitted range causes generation of a normal signal and variation outside of the permitted range causes generation of an alarm signal. The permitted range of values of the condition being monitored by the sensor may be adjusted based on actual values of the condition detected by the sensor, values from the sensor averaged over time or known or expected variations in the values in the area being monitored by the sensor.
A module assembly may include a sensor that produces a DC voltage which varies as a function of the condition being monitored by the sensor. In this case, the identification module converts the DC voltage into digital form.
Another form of a module assembly may include a current loop, with the sensor forming a part thereof. In this case, the identification module converts current readings from the current loop into digital form.
When combining the alarm system with digital sensing capabilities, at least one switch assembly is coupled to the single-wire loop, each including a digital device such as an on/off switch or load and an identification module arranged to generate and provide a signal to the controller indicative of the status of the switch or load.
The invention, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals identify like elements, and wherein:
Referring the accompanying drawings wherein like reference numerals refer to the same or similar elements, an alarm system in accordance with the invention is designated 10 in
In contrast to the alarm system shown in
A schematic of identification module 18 with sensor 28 is shown in
An important advantage of identification module 18 is that it is designed to allow for an internal, pre-determined threshold variation of the readings from sensor 28 before a signal is provided to the controller 12 indicative of a problem with the area being monitored by sensor 28, or a possible fault with the sensor 28. That is, identification module 18 does not simply analyze whether the readings from sensor 28 are above or below a predetermined value, which value would be indicative of a problem or concern with the condition(s) or area(s) being monitored by the sensor 28, and transmit a signal to the controller 12 at that time. Rather, by virtue of the electronic components in identification module 18 and their programming if applicable, identification module 18 is able to monitor the readings from sensor 28, analyze them relative to a predetermined range and then transmits a problem or fault signal (alarm/trouble signal) only when a reading is outside of the range. The predetermined range is adjustable by the user based on, for example, actual readings by the sensor 28, readings from the sensor 28 averaged over time and known or expected variations in the area or condition being monitored by the sensor 28. This adjustment may be performed via the controller 12.
For example, if sensor 28 is a temperature sensor, the identification module 18 can be designed to transmit an alarm signal to the controller 12 only when the temperature is 5 degrees below the expected ambient temperature or 10 degrees above the expected ambient temperature. Thus, a range of permitted variation in the temperature is programmed and/or designed into the identification module 18. Otherwise, if the temperature varies but does not exceed the permitted variation, identification module 18 does not consider the temperature variation to be indicative of a problem with the monitored area or a fault with the sensor 28 (and a normal signal is generated and provided to the controller 12).
In addition to the resistive-type temperature or pressure sensor 28, the illustrated embodiment of alarm system 10 includes identification module 20 which is associated or integrated with a sensor 30 which produces a DC voltage, e.g., in the range of 0-2.0 V or 0-2.5 V. Identification module 20 would then convert the voltage readings from the sensor 30 into digital form, analyze them and transmit a signal to the controller 12 based on the analysis.
A schematic of identification module 20 with sensor 30 is shown in
An important advantage of identification module 20 is that it is designed to allow for an internal, pre-determined threshold variation of the readings from sensor 30, in this case, voltage readings, before a signal is sent to the controller 12 indicative of a problem with the condition(s) or area(s) being monitored by sensor 30, or a possible fault with the sensor 30. This threshold-allowance function would be realized in substantially the same manner as identification module 18 is programmed and/or designed to allow for a variation from sensor 28 as described above.
Alarm system 10 also includes identification module 22 which is associated or integrated with a current loop 32 including one or more sensors. In this case, identification module 22 would convert the current readings from the current loop 32 into digital form, analyze them and transmit a signal to the controller 12 based on the analysis.
A schematic of identification module 22 with current loop 32 is shown in
An important advantage of identification module 22 is that it is designed to allow for an internal, pre-determined threshold variation of the readings from current loop 32, in this case, current readings, before a signal is sent to the controller 12 indicative of a problem with the area being monitored by current loop 32, i.e., by the switches 36 thereof, or a possible fault with the current loop 32 or a switch 36 thereof. This threshold-allowance function would be realized in substantially the same manner as identification module 18 is programmed and/or designed to allow for a variation from sensor 28 as described above.
Using identification modules 18, 20, 22 and associated analog sensors 28, 30 or switch-containing current loop 32, it is possible to construct a single-wire loop alarm system which is capable of not only detecting tripping of switches but also monitoring physical parameters using analog sensors, such as temperature and pressure sensors. Such a single-wire loop alarm system would therefore include both digital devices and analog devices as shown in
In one embodiment of the invention, it is possible to vary the thresholds being applied in the identification modules 18, 20, 22. Both the upper and lower permitted variations can be adjusted based for example, on the actual sensor readings, sensor readings averaged over time or known or expected variations in the conditions in the area(s) being monitored. Commands to change the permitted variations could be sent to the identification modules 18, 20, 22 over the loop 14 from the controller 12.
An advantage arising from the electronic components of the alarm system 10 in accordance with the invention is that it is possible for the identifications modules 16, 18, 20, 22 and associated attachments to be situated up to 6000 feet from the controller 12.
Identification modules 16, 18, 20, 22 are addressable so that controller 12 is able to receive signals from the identification modules 16, 18, 20, 22 and, knowing the location of the identification modules 16, 18, 20, 22 and what they are monitoring, it can provide a meaningful report on the status of the area, being monitored. The status might be that the area is too hot, when a temperature sensor is part of a module assembly, or that there is motion in the area, when a motion detector is part of the module assembly.
In one embodiment of an alarm system in accordance with the invention, a plurality of module assemblies are provided, each containing one or more motion detectors. In a home or business sought to be protected by the alarm system, the motion detectors are arranged to monitor various locations, in particular strategic locations through which a person is most likely to walk. Identification modules are placed next to the motion detectors and adjusted to determine their sensitivity in determining the status of the area being monitored by the motion detector. As noted above, the identification modules can be programmed and/or designed with thresholds so that, in use with motion detectors, a certain amount of detected motion will be permitted, i.e., will not cause generation of an alarm signal to the controller. Adjustment of the sensitivity of the identification modules therefore constitute a determination of how much motion should be required in order to trigger an alarm signal. This type of system is particularly advantageous for homes with pets wherein the identification modules can be adjusted to require a larger amount or degree of motion than that provide by the pet so that the pet will not trigger an alarm/trouble signal.
While a particular embodiment of the invention has been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the invention in its broader aspects, and, therefore, the aim of this application is to cover all such changes and modifications as fall within the true spirit and scope of the invention. For example, although three different types of sensors which generate non-digital signals are disclosed above in the illustrated embodiment of an alarm system, an alarm system in accordance with the invention may include only one of these types of sensors, or only two types of these sensors. The number and type of sensors in an alarm system can be tailored to the area being monitored by the alarm system.
This application claims priority of U.S. provisional patent application Ser. No. 60/729,592 filed Oct. 24, 2005, incorporated by reference herein.
Number | Name | Date | Kind |
---|---|---|---|
3906437 | Brandwein et al. | Sep 1975 | A |
3964302 | Gordon et al. | Jun 1976 | A |
4118700 | Lenihan | Oct 1978 | A |
4310835 | Sefton | Jan 1982 | A |
4524349 | Hyatt | Jun 1985 | A |
4742334 | Teich et al. | May 1988 | A |
4751498 | Shalvi et al. | Jun 1988 | A |
4785285 | Teich et al. | Nov 1988 | A |
4991123 | Casamassima | Feb 1991 | A |
5818334 | Stanley | Oct 1998 | A |
20050072239 | Longsdorf et al. | Apr 2005 | A1 |
Number | Date | Country | |
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20070090941 A1 | Apr 2007 | US |
Number | Date | Country | |
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60729592 | Oct 2005 | US |