This invention relates to a burglar alarm apparatus for use in a plurality of separate premises for example by neighbors in a neighborhood.

BACKGROUND OF THE INVENTION Burglar alarm apparatus generally incudes one or more sensors for detecting the presence of an intruder together with a control unit which is responsive to a signal from the sensor for issuing an alarm signal. The alarm signal can use various transmission systems including the telephone lines, radio transmission, simple audible sound and the like. In some cases the alarm signal is transmitted directly to a police station or to a central security service which can check the voracity of the alarm signal and subsequently contact the police if the alarm appears to be genuine.

In any event a response to the alarm signal is dependent upon a relatively remote respondent with therefore significant delay time before the respondent is able to reach the premises and deal with the intruder.

Many neighborhoods attempt to generate neighborhood watch programs which enable neighbors to watch the homes of other neighbors to prevent or forestall intruders. However no equipment is available which enables the neighborhood to carry out this function more effectively. In addition, a person responsible for more than one location has no equipment available which will assist in providing a watch over the different premises as the person moves back and forth between the premises.

SUMMARY OF THE INVENTION It is one object of the present invention, therefore, to provide an improved burglar alarm apparatus which is useful to assist neighbors in a neighborhood in watching or overseeing the homes of persons in the

neighborhood or which can be used to provide assistance in watching a plurality of different premises.

According to a first aspect of the invention there is provided a burglar alarm apparatus comprising: a plurality of separate alarm elements each for locating in a respective one of a plurality of separate premises; each alarm element having: at least one input for receiving a detector signal from a sensor for detecting presence of an intruder; a control device for responding to the detector signal; a transmitter actuated by said control device for transmitting an alarm signal in response to said detector signal to each of said control devices of the separate alarm elements; a receiver arranged to be responsive to an alarm signal from each of the other alarm elements for communicating to the control device receipt of an alarm signal; and means actuated by the control device for generating in response to an alarm signal from any one of said alarm elements a warning signal for warning persons in the premises at which the respective alarm element is located.

Preferably the alarm signal of each of said alarm elements includes means for identifying the respective alarm element and wherein the control device of each alarm element includes means for identifying that one of the alarm elements from which the alarm signal is received . Preferably there are only two alarm elements, each for communicating with the other.

Preferably there are more than two alarm elements for generating a cell of such alarm elements for use in a neighborhood .

Preferably the transmitter and receiver of each alarm element are mounted in a single housing.

Preferably the single housing contains a sensor for detecting presence of a person. Preferably there is provided a plurality of inputs each for receiving a signal from a respective one of a plurality of alarm conditions.

Preferably the alarm conditions include a panic button actuable by an occupant of the premises to indicate an emergency condition, a smoke detector responsive to presence of smoke in the premises, a vehicle motion sensor for detecting potential car theft and/or a carbon-monoxide detector.

Preferably the control device includes means for transmitting a signal indicating which of the alarm conditions has provided a signal to the respective input and the control device of each alarm element includes means for identifying that one of the alarm conditions. Preferably the control device is programmable to modify the alarm signal so as to provide an identification of the alarm element and the control device is programmable to arrange the receiver so as to be responsive to a predetermined alarm signal modified to provide identification of each of the other alarm elements. Preferably the control device is programmable to enable or disable one or more of said inputs.

According to a second aspect of the invention there is provided a burglar alarm apparatus comprising: an alarm element for locating in a respective one of a plurality of separate premises; the alarm element having: at least one input for receiving a detector signal from a sensor for detecting presence of an intruder;

a control device for responding to the detector signal; a transmitter actuated by said control device for transmitting an alarm signal in response to said detector signal; the control device being programmable to modify the alarm signal so as to provide an identification of the alarm element; a receiver arranged to be responsive to an alarm signal from other similar alarm elements; the control device being programmable to arrange the receiver so as to be responsive to a predetermined alarm signal modified to provide identification of another similar alarm element; and means for generating a warning signal for warning persons in the premises at which the alarm element is located in response to receipt of an alarm signal.

One embodiment of the invention will now be described in conjunction with the accompanying drawings in which: BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic illustration of the apparatus used in a plurality of premises.

Figure 2 is a schematic illustration of a single one of the elements of the apparatus.

In the drawings like characters of reference indicate corresponding parts in the different figures. DETAILED DESCRIPTION

The apparatus as shown in Figure 1 comprises a plurality of alarm elements 1 2 arranged in respective ones of a plurality of premises 7, 8 and 9.

Each alarm element is identical to the others and each includes an internal sensor 10 which is arranged to generate an output signal to an input of a control unit 1 5 in response to detection of the presence of an intruder.

Various types of sensors are available and can be used in the apparatus as required . An infra-red heat sensor is preferred .

The alarm element 12 also includes input terminals 20, 21 and 22. The first two are associated with external sensors 23 and 24 respectively and arranged to receive a signal therefrom by a suitable transmission system such as infrared, radio, wire and the like. One of the sensors comprises a switch operable by a person at the location for example an infirm person who can use the switch to call for assistance in a panic situation. The other of the sensors is a smoke detector responsive to the presence of smoke to provide to the input terminal 21 an indication of fire in the location. Other optional sensors can be attached to the additional input terminal or termainals such as a carbon- monoxide detector (not shown) .

The alarm element further includes a transmitter 13, a receiver 14, the microprocessor control unit 1 5, a manual keypad input 1 6, a warning signal 1 7 which can be visual and/or audible and a visual display unit 1 8. All of the above components are provided in a single transportable housing 1 2A.

The transmitter and receiver are both arranged to transmit and receive similar signals which can be transmitted to and received from similar devices in a suitable range of distances for covering a neighborhood of premises as shown in Figure 1 .

The control unit 1 5 is a micro processor which acts to control the elements in their operations in accordance with the functions as set forth herein after. The control unit allows programming of the functions by the user using information in alpha numeric form set out on the display to call for information from the user to be entered on the key pad.

The transmitter and receiver are arranged to operate at a frequency of 1 .2 GHz at an output power of 0.2 watts so that the transmission/reception is below DOC and FCC requirements for licenses. This

provides a range of approximately 8 km in an unobstructed view and arranged at the order 1 km when the view is obstructed.

The internal infrared sensor 10 has a pyro-electric eye accompanied with filtering circuits which gives an output which is active when the sensor senses heat radiation from an intruder or other person in the area of the alarm element.

The key pad is of the type having sixteen keys allowing various combinations of input and is of a type which is well known to one skilled in the art. The key pad and display as controlled by the microprocessor act initially as a conventional burglar alarm in that the system can be armed and disarmed using a code known to the user in which the code can be programmed in accordance with conventional arrangements.

The panic sensor 22 comprises a conventional switch which can be carried by the user in the location for example an infirm patient who may require emergency assistance or other assistance for everyday tasks so that the person can call for assistance by pressing the panic button 22. A separate smoke alarm sensor 23 is provided separately from the alarm element so that the sensor can be placed in a suitable location for best detecting smoke. In general a number of the alarm elements can be associated together to operate in conjunction for a neighborhood or for related businesses.

For this purpose, each of the elements is encoded with its own transmission code selected by the cell of users. The encoding is effected using the key pad in conventional manner. These encoded transmission codes are then programmed into each of the other alarm elements as receiver codes.

Thus each element will be programmed with the transmitter codes of each of the other elements. All of the receivers are therefore continuously receiving

transmissions in the common frequency and are looking for the transmission of transmitter codes programmed into that alarm element which are therefore the transmitter codes of the associated alarm elements.

In the event that the control processor 1 5 which is scanning the data received from the receiver 14 notes the transmission code from one of the other alarm elements, this information is then provided from the control processor as a warning signal at the signal 17 and the information identifying the transmission code and its associated alarm element is displayed at the display 1 8. Thus when coding each alarm element with the required transmission codes of the other elements, this transmission code is associated with an address or identification of the alarm element concerned. This can be programmed by the user as a simple key word for example identifying the name of the occupant at the particular location. In addition to transmitting the transmitter code, each alarm element is arranged to transmit information identifying which of the inputs from the various sensors has been activated. Thus the transmission code is transmitted along with that information identifying the sensor and the same information is displayed to each of the other alarm elements. Thus for example each of the other alarm elements will display the location where the alarm element has been activated and will at the same time display the type of activation which has occurred, for example " Tim's house- burglar " or " Smith's-fire " or " Grandma-panic ".

Each of the users at the locations where the alarm elements have received this information can therefore take the necessary action to deal with the alarm condition.

The unit is entirely self contained and powered by standard house current. The unit contains a battery ( not shown ) as a backup in case power is cut to the premises.

The unit also contains an external contact 30 capable of reading information from a " smart card " or a small " Dallas-type " button, which can be used instead of the keypad for programming neighboring units as well as for arming and disarming the unit. Information can therefore be entered into the units using the input 30 or using the key pad .

The housing is relatively small and self contained so that it may be placed on a shelf or table.

The unit, when initially tripped or activated by transmission from a related remote alarm unit, is not activated so that no display is provided to the user in that location for a set period of time. During this time the remote unit may be deactivated by the user at that location. This can be done by the key pad or by touching the appropriate smart card or Dallas type button to the contacts on the unit, there by canceling the alarm. The neighboring units, having received the initial signal from the remote will activate the alarm tone unless they receive a further signal from the same remote unit within the predetermined period telling them that the remote unit has been disarmed . This delayed alarm eliminates the need for remote disarming.

The arming and disarming mechanism, whether the smart card or Dallas type button, must be such that one unit can have several duplicate smart cards or Dallas type buttons to support multiple users. The following functions maybe programmable: 1 . Arm/Disarm code { 4 digits )

2. Personalization of transmission code ( up to 10 characters )

3. Infrared bypass { enable/ infrared sensor )

4. Exit entry delay ( 0 to 99 seconds )

5. Back lit display for easy reading ( activated upon keystroke, turns off after 20 seconds }

6. Silent/Audible alarm ( programmable )

7. Visual/Non-visual alarm ( programmable ) 8. Alarm on-off timer ( programmable )

9. Quick arm ( not disarm )

10. Wireless Transmission on/off ( programmable )

1 1 . Wireless Reception on/off ( programmable ) . 1 2. Enable/Disable smoke sensor 1 3. Enable/Disable Panic sensor

The apparatus therefore described allows a number of neighbors to obtain the complete apparatus including the separate units each for location at a respective one of the premises. Thus when any of the intruder alarms is actuated, that premises transmits a signal to the other premises which is then received and informs the occupants of those premises of the intruder. The apparatus therefore can be used to enhance the neighborhood watch process so that the neighbors can receive signals from the interior of the premises to be watched. The apparatus is thus reciprocal in that each premises can be arranged to watch all of the other premises. While the sensor is shown as an internal item in the drawings, it is of course possible that the sensor will be mounted externally from the control unit. In addition, the unit can be connected to the AC mains supply for receipt of power and can use the same connection for utilizing the building wiring as an antenna. In addition to the use in a neighborhood arrangement, the devices can be used to monitor other associated premises such as the house and shop of a user so that the user when on either premises can monitor the other. The device can also be used in a garage adjacent to a main premises. The device

can be used even in a car where the external terminal can be connected to a conventional vehicle motion sensor as the input.

Since various modifications can be made in my invention as herein above described, and many apparently widely different embodiments of same made within the spirit and scope of the claims without departing from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense.