GB2029063A

GB2029063A - Inactivity Alarm

Info

Publication number: GB2029063A
Application number: GB7929987A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-05-31
Filing date: 1979-08-30
Publication date: 1980-03-12

Abstract

Alarm apparatus for monitoring the well-being of old or infirm people living alone in individual dwellings comprises a warning device (35, 36), a pressure pad switch (21, 22) for actuation by a person stepping on the pressure pad of the switch, and a timer (11) connected to the pressure pad switch for resetting in response to actuation of the switch and being arranged to activate the alarm device (35, 36) at the end of its timing period unless previously reset by actuation of the switch (21, 22). <IMAGE>

Description

SPECIFICATION Monitoring Device This invention relates to alarm apparatus.

According to the invention there is provided alarm apparatus comprising a warning device, a pressure pad switch for actuation by a person stepping on the pressure pad of the switch, and a timer being connected to the pressure pad switch for resetting in response to actuation of the switch and being arranged to activate the alarm device at the end of its timing period unless previously reset by actuation of the switch.

The alarm apparatus of the present invention finds particular application in monitoring the wellbeing of old or infirm people living along.

The lack of adequate monitoring of the wellbeing of old or infirm people living alone.

individual dwellings is an increasing problem. At present the detection of something amiss with such old or infirm people is entirely dependent on the social conscience, good will and memory of the community at large, their families, if available, neighbours, friends, delivery people and the police.

It is an accepted fact that old or infirm people are often neglected, and situations frequently arise in which unnecessary suffering and even premature death occur as a result of the inability of these people to attract attention to their predicament, following in some cases quite minor accidents or illness which restrict their mobility.

Old or infirm people who live alone will of necessity normally be moderately active or some degree and it is a particular object of the present invention to provide an alarm apparatus which will give warning to the community in the event of a change in the activity of such an old or infirm person, indicating that all is not well.

Accordingly, in a particular aspect of the invention, there is provided, in a dwelling, alarm apparatus comprising:-- a warning device for giving, when activated, a warning detectable externally of the dwelling; a plurality of pressure pad switches each for actuation by an occupant of the dwelling stepping on the pad and each located on the floor of the dwelling at a place normally frequented by the occupant; and a timer having a given timing period, the timer being connected to the pressure pad switched for resetting in response to actuation of any of the switches and being arranged to activate the alarm device at the end of its timing period unless previously reset by actuation of one of the pressure pad switches.

According to a preferred feature of the invention, means are provided for changing the timing period of the timer from a normal timing period to a longer timing period. This allows the timer to be set to its longer timing period during an expected relatively long period of inactivity within the dwellings, for example during the nightime and during absences of the occupant from the dwelling.

Conveniently, the means for changing the timing period of the timer comprises a light sensor which, when illuminated, provides the normal timing period and, when unilluminated, provides the longer timing period of the timer. The light sensor may be arranged to be illuminated by ambient light and a shutter may be provided for preventing ambient light falling on the light sensor to select the longer timing period. The use of such a light sensor allows the timer to switch automatically to its longer timing period during the hours of darkness in the dwelling, whilst the shutter allows such longer timing period to be consciously selected by the occupant during the hours of daylight or artificial light.

The light sensor may suitably comprise a light sensitive resistor whose resistance decreases when the resistor is illuminated and which is incorporated in an RC circuit of the timer.

Advantageously, the alarm apparatus comprises one or more manually operable override switches for directly activating the warning device. Each override switch may be installed at a convenient location in the dwelling so that the occupant can activate the warning device without delay, should the need arise. One or more burglar alarm switches may also be incorporated in the apparatus for directly activating the warning device. Each burglar alarm switch is arranged to activate the warning device on opening of a respective door or window by an intruder.

The warning device may be a visual warning device and, in an embodiment of the invention comprises an electric lamp connected in a power circuit in series with a normally open power switch controlled by the timer and closed in response to the timer reaching the end of its timing period. To enhance the visual effect of the warning device the power switch may be controlled by a flasher unit which is set in operation by the timer at the end of its timing period and alternately opens and closes the power switch to flash the lamp on and off. The power switch is preferably in the form of a semiconductor device, such as a thyristor, having its control electrode connected to the flasher unit.

In this case, the flasher unit conveniently comprises a flip-flop having one of its outputs connected to the control electrode of the semiconductor device. If desired, the warning device may comprise two lamps which may be of different colours, each controlled by a respective power switch operated in antiphase by the flasher unit.

In order that the invention may be readily understood, an embodiment thereof will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a block circuit diagram of the electrical circuitry of alarm apparatus embodying the invention for use in a dwelling; Figure 2 shows a practical form of the circuitry of Figure 1; and Figure 3 is a schematic perspective view of a combined control box and warning device of the alarm apparatus.

Referring to Figure 1, an alarm device embodying the invention comprises an input transformer 1 having a primary 2 for connection to a 240 volts a.c. electricity supply of a dwelling and a centre-tapped secondary 3 providing a 1 9 volt d.c. supply on positive and negative lines 4 and 5. The positive line 4 is connected to the ends of the secondary 3 via rectifiers 6 and 7, and line 5 is connected to the centre tap 8 of the secondary and to the neutral end 9 of the transformer primary 2. A smoothing capacitor 10 is provided to smooth the rectified d.c. supply.

A timer 11 is powered from the d.c. supply on lines 4 and 5, the timer being connected to positive line 4 via a lead 12 including a voltagedropping resistor 13 providing 5 volts at the timer and to negative line 5 via a lead 14. A telltale light-emitting diode 1 5 is connected between the timer 11 and line 5 and is lit when the timer 11 is operating. The timer 11 comprises an RC time constant circuit (not shown in detail) which includes an adjustable resistor 1 6 for manually adjusting the time-constant of the RC circuit, and a light-sensitive resistor 1 7 providing a change in the time constant of the RC circuit in dependence upon the ambient light conditions.The resistor 1 7 has a low resistance when illuminated by ambient light and a high resistance when unilluminated and is arranged so that it can be isolated from the ambient light by a manually operable shutter 48 (see Figure 3) to select the high resistance state in presence of ambient light.

The time constant of the RC circuit determines the timing period of the timer 11 by determining the frequency of a timer oscillator (not shown) which delivers pulses to a timer counter (not shown) arranged to produce an alarm-activating signal at timer output 18 when a predetermined count is achieved. A resetting input 19 of the timer is connected to a resetting circuit 20 via normally open contacts 21,22 of a plurality of foot-operated pressure pad switches electrically connected in parallel with each other. Each pressure pad switch is located on the floor of the dwelling at a place frequented by the occupant, for example in the W.C. and kitchen sink areas.

The resetting circuit 20 comprises a capacitor 23 and a resistor 24 connected in parallel between pressure pad contacts 22 and negative d.c. line 5.

A flasher unit 25 is powered from the d.c. lines 4 and 5 via a positive lead 26 incorporating a voltage-dropping resistor 27 providing 5 volts at the unit 25 and via a negative lead 28. An enabling input 29 of flasher unit 25 is connected to timer output 18 via a diode 30 so that the flasher unit is set in operation in response to the alarm-activating signal delivered on the timer output. The flasher unit 25 has two outputs 31 and 32 each connected to the control electrode of a respective thyristor 33 or 34 which is connected in series with a respective lamp 35 or 36 between the positive and neutral lines of the 240 volt a.c.

supply. On enabling of the flasher unit 25 the outputs 31 and 32 are alternately energised so as to open and close the thyristors 33 and 34 and flash the two lamps 35 and 36 in antiphase. A pushbutton 37 is provided in a lead 38 connected to lead 26 and, when held closed, enables the flasher unit to test the operation of the flasher unit 25 and lamps 35 and 36.

One or more manually operable, normally closed override or emergency switches 38 are each connected in parallel with the pushbutton 37 for directly enabling the flasher unit 25. Each override switch may be installed at a convenient location in the dwelling, for example in a bedside location, so that the occupant can activate the warning device without delay, should the need arise.

Normally open burglar alarm switches (not shown) incorporated in the dwelling may each be connected in parallel with the pushbutton 37.

These burglar alarm switches may be arranged to close upon opening of the window or door by an intruder and thereby to enable the flasher unit 25 and activate the alarm. The burglar alarm switches may be connected in series with a master switch (not shown) to permit disabling of the burglar alarm switches.

Figure 2 of the drawings illustrates a practical form of the Figure 1 circuitry, in which the timer 11 is based on an integrated circuit 40 and the flasher unit comprises a 1:1 M.S.R. flip-flop constituted by four logic gates 41 to 44. The time constant circuit of the timer comprises adjustable resistor 16, light-sensitive resistor 17, fixed resistors 1 7A and 1 7B and capacitor 17C.

As shown in Figure 3, the apparatus may comprise a combined control box and warning device having a rectangular casing 45 housing the circuitry of the apparatus, except for the remotely disposed pressure pads and the auxiliary override and burglar alarm switches (e.g. 38) whose wiring is connected to the control box at a pressure pad input 46 and an auxiliary switch input 47. Figure 3 also shows the telltale light-emitting diode 15, the light dependent resistor 1 7 and the pivotable shutter 48 which controls the exposure of the resistor 17 to ambient light. The two lamps 35 and 36 are mounted side-by-side in suitable bulb holders on the top of the casing 45. Power is supplied to the control box and warning device by a mains cable 49.

In use, the combined control box and warning device of the described apparatus is placed in a prominent indoor position in the residence with the lamps clearly visible from the outside so that, when activated, they will attract the attention of neighbours, tradesmen, passers-by or the police.

In normal use in daylight or artificial light, the shutter 48 is pivoted to its illustrated open position in which the light-sensitive resistor 1 7 is subjected to ambient light. The resistor 1 7 then sets the shorter timing period of timer 11 which may be, for example, four hours. Normal activity of the occupant of the residence will result in at least one of the pressure pad switches being closed in any period of four hours, so that the timer 11 will be continually resent before it can reach the end of its timing period and the warning device will remain inoperative.Should the normal activity of the occupant be impaired for any reason for a period of four hours the pressure pad switches will remain open, the timer 11 will reach the end of its timing period and activate the flasher unit 25 and the lamps 35 and 36 to give the alarm. Any predetermined absence of the occupant from the residence during daylight hours can be accommodated by closing the shutter 48 to exclude the resistor from ambient light and place it in its high resistance state which sets the longer timing period, for example 10 hours, of the timer 11.

During normal nightime use the resistor 1 7 is in darkness and thus automatically adopts its high resistance state, allowing the occupant to remain inactive during normal hours of sleeping and awakening without the alarm device being activated.

In the event of an emergency either during the daytime or nightime, the occupant can initiate immediate operation of the warning device by closing one of the override switches 38. Where burglar alarm switches are also included in the apparatus, these will also give warning of an intruder, whether during daytime or nightime and regardless of the current timing period of the timer 11.

The adjustable resistor 1 6 allows limited adjustment of both timing period of the timer 11 to suit the particular circumstances and requirements of the occupant of the residence.

For example, the shorter period may be adjusted within the range of two to six hours and the longer period within the range of nine to twelve hours.

The power consumption of the apparatus is low during normal monitoring operation, the current requirement being approximately 2 mA and giving approximately 2000 hours operation for the cost of one electrical unit (1 killowatt hour). When the alarm device is activated, the current requirement increase to approximately 0.4 A depending upon the wattage of the lamps 35 and 36.

The 240 volt a.c. mains supply is completely isolated from the casing 45 and the remote switches, i.e. pressure pad switches and auxiliary switches, ali operate on 5 volts, so that the device is entirely safe.

The apparatus described with reference to Figures 1 to 3 is only powered from the domestic mains electricity supply and so will not operate during a power failure, although it will automatically reset and commence a new timing period on resumption of the power supply. It is envisaged, however, that the apparatus may be provided with an auxiliary d.c. power supply consisting of batteries, preferably of the rechargeable kind, so that the timer continues to operate during a mains failure. Such an auxiliary power supply would not be able to operate the warning lamps but would keep the timer updated according to the activity of the occupant of the residence. Should the timer reach the end of its timing period during a mains failure, the restoration of the mains supply would result in the energisation of the lamps without the need for a complete timing period to elapse. To provide complete protection during a mains failure, a d.c.

to a.c. converter powered by the auxiliary d.c.

power supply could be included in the apparatus to provide an a.c. supply of appropriate voltage for energising the lamps.

Whilst the above described apparatus of Figures 1 to 3 comprises a visual warning device employing electric lamps, apparatus employing the invention may alternatively or additionally have an audible warning device, such as a bell or siren. Moreover, although the warning device of the described embodiment of the invention has a combined control box and warning device, clearly the warning device could be installed separately and could, for example, be mounted outside the dwelling in a conspicuous position.

Claims

1. An alarm apparatus comprising a warning device, a pressure pad switch for actuation by a person stepping on the pressure pad of the switch, and a timer connected to the pressure pad switch for resetting in response to actuation of the switch and being arranged to activate the alarm device at the end of its timing period unless previously reset by acutation of the switch.

2. In a dwelling, alarm apparatus comprising:- a warning device for giving when activated, a warning detectable externally of the dwelling; a plurality of pressure pad switches each for actuation by an occupant of the dwelling stepping on the pad and each located on the floor of the dwelling at a place normally frequented by the occupant; and a timer having a given timing period, the timer being connected to the pressure pad switched for resetting in response to actuation of any of the switches and being arranged to activate the alarm device at the end of its timing period unless previously reset by actuation of one of the pressure pad switches.

3. Alarm apparatus according to claim 1 or claim 2, in which means are provided for changing the timing period of the timer from a normal timing period to a longer timing period.

4. Alarm apparatus according to claim 3, in which the means for changing the timing period of the timer comprises a light sensor which, when illuminated, provides the normal timing period and, when unilluminated, provides the longer timing period of the timer.

5. Alarm apparatus according to claim 4, in which the light sensor is arranged to be illuminated by ambient light, and a shutter is provided for preventing ambient light falling on the light sensor to select the longer timing period.

6. Alarm apparatus according to claim 4 or claim 5, in which the light sensor comprises a light sensitive resistor whose resistance decreases when the resistor is illuminated and which is incorporated in an RC circuit of the timer.

7. Alarm apparatus according to any preceding claim, in which there is provided one or more manually operable override switches for directly activating the warning device.

8. Alarm apparatus according to any preceding claim, in which one or more burglar alarm switches are incorporated in the apparatus for directly activating the warning device.

9. Alarm apparatus according to claim 8, in which each burglar alarm switch is arranged to activate the warning device on opening of a respective door or window by an intruder.

10. Alarm apparatus according to any preceding claim, in which the warning device comprises an electric lamp connected in a power circuit in series with a normally open power switch controlled by a timer and closed in response to the timer reaching the end of its timing period. ~~~~~~~~~~~~~~~

11. Alarm apparatus according to claim 10, in which the power switch is controlled by a flasher unit which is set in operation by the timer at the end of its timing period and alternately opens and closes the power switch to flash the lamp on and off.

12. Alarm apparatus according to claim 11, in which the power switch comprises a semiconductor device, such as a thyristor, having its control electrode connected to the flasher unit.

13. Alarm apparatus according to claim 12, in which the flasher unit comprises a flip-flop having one of its outputs connected to the control electrode of the semiconductor device.

14. Apparatus according to any one of the claims 10-13 in which the warning device comprises two lamps, which may be of different colour each controlled by a respective power switch operated in antiphase by the flasher unit.

1 5. In or for a dwelling house, alarm apparatus substantially as described herein with reference to the accompanying drawings.