GB1578525A

GB1578525A - Alarm system

Info

Publication number: GB1578525A
Application number: GB667176A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1977-05-19
Filing date: 1977-05-19
Publication date: 1980-11-05

Description

(54) ALARM SYSTEM (71) I, ANTHONY EDWARD SMITH, a British subject of 21, Wensleydale Avenue, Blackpool, Lancashire, England, do hereby declare the invention for which I pray that a patent may be granted to me and the method by which it is to be performed to be particularly described in and by the following statement: The present invention relates to an alarm system which provides an alarm signal after a predetermined time unless the user operates a deactivating control within said period. The invention has particular, but not exclusive application to alarm systems for use by invalids or infirm persons, especially elderly persons, living alone.

There is well-recognised danger that invalids or infirm persons living alone will suffer further incapacity without having sufficient time to make their need for assistance known. Various devices have been proposed to assist such persons in making their incapacity known but the majority of these devices presently available commercially rely upon the person operating some form of warning device, for example, placing a card in the window of their dwelling or pressing a control to actuate a mechanical or electrical warning device. However, alarm systems have been proposed which are operative to provide an alarm signal when the person fails to carry out a cancelling or deactivating operation, (see for example, U.K. Patent Nos. 1010183 and 1318891). It is an object of this invention to provide an improved alarm system of said latter type.

According to the present invention, there is provided an alarm system comprising a primary timer for providing a first alarmsignal at consecutive predetermined major time intervals; preliminary alarm means actuated by said alarm signal to indicate that a said interval has expired; a manually operable override control operable at any time during each of said intervals to cancel the preliminary alarm signal due at the end of the respective interval and being the only override control for cancelling said alarm signal; a secondary timer for providing a second alarm signal at a predetermined minor time interval after actuation of the preliminary alarm means; and main alarm means actuated by said second alarm signal to indicate that the combined major and minor time intervals have expired.

Preferably, the alarm system is electrically powered, by, for example, mains voltage or accumulators such as dry cell batteries. Thus, the timer can be an electric clock and the alarm means can be an electrically illuminated sign. The use of accumulators renders the system of the invention independent of the mains electricity supply to the dwelling in which it is used. It is preferred that the system should include rechargeable accumulator(s) and mains voltage charging circuit whereby the system is normally powered by mains voltage but will operate on the accumulator(s) in the event of a mains voltage failure.

In a particularly preferred embodiment the primary timer comprises a binary divider to which periodic electrical impulses are applied. Suitably, the primary and secondary timers are in an electrical circuit comprising CMOS-type integrated circuits, especially binary ripple counter(s) and AND gate(s).

The primary timer can be adapted to provide an alarm signal at consecutive predetermined major time intervals, the duration of which intervals are independent of operation of the override control. Alternatively, said time intervals can commence with each occasion that said control is operated and be prematurely terminated upon next operation of the override control within the predetermined time interval. The predetermined major and minor time intervals can be fixed when assembling the timer or provision can be made for adjusting said intervals as required. Equal predetermined major time intervals can be provided or the timer programmed to provide predetermined major time intervals of different lengths depending upon the time of day.For instance, two or three hour intervals can be provided during normal waking hours, e.g. 9a.m. to 10 p.m., but a single, e.g. eleven, hour interval provided overnight.

The preliminary and main alarm means can be audio and/or visual alarms but preferably the main alarm means is visual with or without a supplementary audio alarm. Usually, the main alarm will be located at a position remote from the timer. It is especially preferred that said main visual alarm should be a illuminatable sign adapted to be continuously or intermittently (i.e. flashing) illuminated in response to the alarm signal.

Advantageously, the signal is adapted to be displayed in a window by, for example, standing on a window sill or secured to the window glass. Suitably the sign includes words or a device which when illuminated clearly indicates to a passer-by that assistance is required. For example, the sign might have the letters "S.O.S." or the word "HELP".

The override control is manually operable and can be located remote from or adjacent to the primary timer. Suitably said control can be a press-button which when depressed closes an electrical circuit to cancel the next preliminary alarm signal. Alternatively, said press-button can operate a mechanical linkage to serve the same purpose. It is important to note however that the override control is adapted to cancel only the next preliminary alarm signal due and not subsequent preliminary alarm signals and that such cancellation can be effected at any time during the respective major time interval. In this manner, the alarm system of this invention is quite distinct from conventional clock alarms in which any override control cannot be operated once during each sequential time interval to cancel only the next alarm signal.

Conventional alarm systems require a separate operation to release the override control after the due time for an alarm signal in order to actuate the alarm for the next signal due.

It will be appreciated that the preliminary timer provides an alerting signal a short time before the main alarm means operates in order to remind the user that the override control has not been operated within the major time interval. In this manner inadvertant operation of the main alarm means can be avoided.

It will be appreciated that the alarm system of this invention will provide an indication of the expiry of any predetermined time interval during which the override control is not operated. Thus incapacity of the user to the extent of not being able to operate the override control will be indicated after expiry of said interval.

Conveniently, the alarm system can be accommodated within a single housing of, for example, plastics material, although it is possible for the components parts thereof to be located in different positions in the dwelling.

The alarm system can incorporate a temperature-sensitive override control to automatically actuate the main alarm means in the event that the temperature at a monitored location falls below and/or rises above predetermined threshold value(s). Thus the system can provide a warning of a risk of hypothermia and/or a fire alarm. Moreover, the system usually will have a manually operable switch to immediately actuate the main alarm in the event that immediate assistance is required.

The following is a description by way of example only and with reference to the accompanying drawings of alarm systems in accordance with preferred embodiments of the present invention. In the drawings: Figure 1 is a block diagram of an alarm system in accordance with a first preferred embodiment of the invention, and Figure 2 is a circuit diagram of an alarm system in accordance with a second preferred but simplified embodiment of the invention.

Referring first to Figure 1, an alarm system comprises an electrical charger 1 supplied with mains voltage electricity and charging a bank of rechargeable accumulators 2. A primary timer 3 is powered by said accumulators 2 and is arranged to provide a preliminary alarm signal after a predetermined major time interval of, for example, 24 hours. Said signal actuates a secondary timer 4 but manual operation of a cancel/reset switch 5 at any time resets the primary timer 3 to commencement of the time interval and cancels both said alarm signal and an alarm signal from the secondary timer if said signal(s) have been generated. The secondary timer 4 provides a main alarm signal after a predetermined minor time interval of, for example, 5 minutes, following actuation unless the switch 5 is operated in the interim.

The preliminary alarm signal actuates a preliminary alarm 6 which can be a buzzer and/or lamp and which is intended to be located within a dwelling in which the system is to be installed. Accordingly, alarm 6 constitutes a reminder to the user of the system to operate the switch 5 unless a main alarm 7 is to be given. The alarm 7 can be a buzzer and/or lamp and is intended to be located remotely from the switch 5, usually externally of the dwelling, to attract the attention of persons other than the user of the system.

A manually-operable emergency switch 8 is connected in parallel with the timers 3, 4 to override said timers and provide immediate actuation of alarm 7 if urgent assistance is required.

A low temperature sensor 10 is connected in parallel with timer 3 to provide the preliminary alarm signal in the event that the temperature of the monitored location falls below a predetermined minimum level. Similarly, a high temperature sensor (i.e. fire sensor) 9 is connected in parallel with switch 8 to provide the main alarm signal in the event that the temperature at said location exceeds a predetermined maximum level.

Usually, the major and minor time intervals will be fixed during manufacture but adjustable timers 3, 4 can be provided if required.

The components 1 to 6 and 8 to 10 conveniently are located in a single housing with the main alarm 7 remote therefrom.

The timers 3, 4, switches 5, 8 alarms 6, 7 can be incorporated in a circuit substantially as shown in Figure 2, which figure shows a circuit corresponding to a block diagram differing from Figure 1 in that itenis 1, 2, 9 & 10 are omitted.

Referring to Figure 2, a 240 volt A.C.

mains electrical supply 5 is applied to the primary winding of a transformer 11 having two 12 volt secondary windings. The voltage VCC derived from one of said secondary windings is applied to the respective last pins of integrated circuits A, B, C, D constituting the primary and secondary timers 3, 4. The voltage VDD derived from the other of said secondary windings is applied to the alarms 6, 7 as shown. The integrated circuits are of the CMOS-type with A and B being 14 stage binary ripple counters (reference CD4020) and C and D being quad 2-input AND gates (reference CD 4081). The circuit diagram employs standard graphical symbols and does not require detailed explanation except in respect of the alarms 6, 7. Alarm 6 comprises a green lamp 6a in parallel with a buzzer 6b whereas alarm 7 comprises an illuminatable "HELP" sign 7a, a loud buzzer 7b and a red lamp 7c.The lamp 7c is mounted adjacent lamp 6b on a housing enclosing the circuit except for sign 7a and buzzer 7b which are intended to be located remotely from the housing, for example externally of a dwelling in which the alarm is situated or in a window of said dwelling.

It will be appreciated that the invention is not restricted to the details described above with reference to the drawings but that numerous modifications and variations can be made without departing from the scope of the invention, as defined in the following Claims. It will be appreciated also that the alarm system is of use for purposes other than as an alarm to bring assistance to elderly or infirm persons. For example, the system could be readily adapted for security use whereby an alarm is given if a guard fails to operate the override control within the relevant time period.

WHAT I CLAIM IS: 1. An alarm system comprising a primary timer for providing a first alarm-signal at consecutive predetermined major time intervals; preliminary alarm means actuated by said alarm signal to indicate that a said interval has expired; a manually operable override control operable at any time during each of said time intervals to cancel the preliminary alarm signal due at the end of the respective interval and being the only override control for cancelling said-alarm signal; a secondary timer for providing a second alarm signal at a predetermined minor time interval after actuation of the preliminary alarm means; and main alarm means actuated by said second alarm signal to indicate that the combined major and minor time intervals have expired.

2. An alarm system as claimed in Claim 1 wherein said major time interval has a duration of the order of hours.

3. An alarm system as claimed in Claim 2 wherein said minor time interval has a duration of the order of minutes.

4. An alarm system as claimed in any one of the preceding Claims adapted for installation in residential premises.

5. An alarm system as claimed in Claim 4 when installed in residential premises.

6. An alarm system as claimed in any one of the preceding Claims wherein the manually operable override control is adapted to set the primary timer to commencement of the next major time interval.

7. An alarm system as claimed in Claim 6 adapted to be electrically powered.

8. An alarm system as claimed in Claim 7 wherein the primary timer comprises a binary divider to which periodic electrical impulses are applied.

9. An alarm system as claimed in Claim 8 wherein the primary and secondary timers are in an electrical circuit comprising CMOS-type integrated circuits.

10. An alarm system as claimed in Claim 9 wherein said integrated circuits comprise a binary ripple counter and an AND gate.

11. An alarm system as claimed in any one of Claims 7 to 10 including rechargeable accumulator(s) and a mains voltage charging circuit whereby the system is normally powered by mains voltage, but will operate on the accumulator(s) in the event of a mains voltage failure.

12. An alarm system as claimed in any one of the preceding Claims wherein the main alarm means is disposed remote from the timers.

13. An alarm system as claimed in any one of the preceding Claims including a temperature-sensitive override control to automatically actuate the main alarm means

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. actuation of alarm 7 if urgent assistance is required. A low temperature sensor 10 is connected in parallel with timer 3 to provide the preliminary alarm signal in the event that the temperature of the monitored location falls below a predetermined minimum level. Similarly, a high temperature sensor (i.e. fire sensor) 9 is connected in parallel with switch 8 to provide the main alarm signal in the event that the temperature at said location exceeds a predetermined maximum level. Usually, the major and minor time intervals will be fixed during manufacture but adjustable timers 3, 4 can be provided if required. The components 1 to 6 and 8 to 10 conveniently are located in a single housing with the main alarm 7 remote therefrom. The timers 3, 4, switches 5, 8 alarms 6, 7 can be incorporated in a circuit substantially as shown in Figure 2, which figure shows a circuit corresponding to a block diagram differing from Figure 1 in that itenis 1, 2, 9 & 10 are omitted. Referring to Figure 2, a 240 volt A.C. mains electrical supply 5 is applied to the primary winding of a transformer 11 having two 12 volt secondary windings. The voltage VCC derived from one of said secondary windings is applied to the respective last pins of integrated circuits A, B, C, D constituting the primary and secondary timers 3, 4. The voltage VDD derived from the other of said secondary windings is applied to the alarms 6, 7 as shown. The integrated circuits are of the CMOS-type with A and B being 14 stage binary ripple counters (reference CD4020) and C and D being quad 2-input AND gates (reference CD 4081). The circuit diagram employs standard graphical symbols and does not require detailed explanation except in respect of the alarms 6, 7. Alarm 6 comprises a green lamp 6a in parallel with a buzzer 6b whereas alarm 7 comprises an illuminatable "HELP" sign 7a, a loud buzzer 7b and a red lamp 7c.The lamp 7c is mounted adjacent lamp 6b on a housing enclosing the circuit except for sign 7a and buzzer 7b which are intended to be located remotely from the housing, for example externally of a dwelling in which the alarm is situated or in a window of said dwelling. It will be appreciated that the invention is not restricted to the details described above with reference to the drawings but that numerous modifications and variations can be made without departing from the scope of the invention, as defined in the following Claims. It will be appreciated also that the alarm system is of use for purposes other than as an alarm to bring assistance to elderly or infirm persons. For example, the system could be readily adapted for security use whereby an alarm is given if a guard fails to operate the override control within the relevant time period. WHAT I CLAIM IS:

1. An alarm system comprising a primary timer for providing a first alarm-signal at consecutive predetermined major time intervals; preliminary alarm means actuated by said alarm signal to indicate that a said interval has expired; a manually operable override control operable at any time during each of said time intervals to cancel the preliminary alarm signal due at the end of the respective interval and being the only override control for cancelling said-alarm signal; a secondary timer for providing a second alarm signal at a predetermined minor time interval after actuation of the preliminary alarm means; and main alarm means actuated by said second alarm signal to indicate that the combined major and minor time intervals have expired.

7. An alarm system as claimed in Claim 6 adapted to be electrically powered.

in the event that the temperature at a monitored location falls below and/or rises above predetermined threshold value(s).

14. An alarm system as claimed in any one of the preceding Claims including a manually-operable switch to immediately actuate the main alarm means.

15. An alarm system substantially as hereinbefore described with reference to Figure 1 of the accompanying drawings.

16. An alarm system substantially as hereinbefore described with reference to Figure 2 of the accompanying drawings.