GB2546489A

GB2546489A - Lighting apparatus

Info

Publication number: GB2546489A
Application number: GB1600942.5A
Authority: GB
Inventors: Tordjman Avraham
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-01-19
Filing date: 2016-01-19
Publication date: 2017-07-26
Also published as: GB201600942D0

Abstract

A lighting apparatus 100 comprises a lamp 102 for illuminating an exterior location; means 104 for determining an ambient light level; a passive infrared, PIR, sensor 106 for detecting the presence of a body emitting infrared; and bypass means 112 for bypassing the PIR sensor, wherein the apparatus is configured to operate: in a first configuration whereby the lamp is illuminated when the ambient light level is below a predetermined threshold level and the PIR sensor detects the presence of a body emitting infrared, and in a second configuration whereby the lamp is illuminated when the ambient light level is below a predetermined threshold level and when the bypass means is operative to bypass the PIR sensor.

Description

LIGHTING APPARATUS

The present invention relates to a lighting apparatus. In particular this invention relates to a security light which incorporates means for determining ambient light levels and a passive infrared sensor.

Security lights/floodlights are commonly placed around domestic and commercial properties in order to illuminate the area around the property. Since the lights are used to illuminate a large area it is common to use high power lamps in such lights. Since these lamps typically use a large amount of electricity it is common to include sensors to allow for efficient use of electricity. These sensors include an ambient light sensor and a passive infrared (PIR) sensor.

An ambient light sensor controls the light so that the lamp is only activated during the night. A PIR sensor is a sensor which detects infrared light radiating from a body, such as a person or animal. The PIR sensor controls the light so that it is only illuminated when a person or animal comes within the detection field of the sensor. The PIR sensor thereby provides the dual function of energy efficiency, since the light is only operated when a person or animal enters the detection field, and a security warning, since individuals in a building are alerted by the activation of the light to the arrival of an intruder and the intruder becomes aware that they may be visible.

The light source commonly used in these types of floodlights are linear halogen bulbs having power ratings of between 150W to 1000W. More recently LED arrays have been used in these lights, since LED arrays have a much lower power consumption compared to halogen bulbs. Nevertheless the power usage of LED arrays can be significant over time and the role of alerting to the presence of intruders remains even when LED arrays are used.

According to Jewish law, Jews are required to abstain from creative activities on the Sabbath (‘Shabbat’) and on special Holidays (‘Yom Tov’). The Jewish day starts at twilight (and not at midnight). On the Jewish Sabbath and Holidays the restriction of performing creative activities starts shortly before sunset (when the sun has descended completely below the horizon) and ends the following evening after nightfall, in particular once three medium-sized stars are visible in the sky. Consequently the period of time when creative activities are prohibited is location specific and typically lasts for 25 hours.

One activity which is forbidden on the Jewish Sabbath and Holidays is the switching on and off of lights. The prevalence of security lights as described above has caused difficulties for practicing Jews, since by walking down a road where such lights are installed one can easily activate these security lights, albeit unintentionally.

The present invention aims to address this problem and provides a lighting apparatus which complies with Jewish law.

According to a first aspect of the invention, there is provided a lighting apparatus comprising: a lamp for illuminating an exterior location; means for determining an ambient light level; a passive infrared, PIR, sensor for detecting the presence of a body emitting infra red; and bypass means for bypassing the PIR sensor, wherein the apparatus is configured to operate: in a first configuration whereby the lamp is illuminated when the ambient light level is below a predetermined threshold level and the PIR sensor detects the presence of a body emitting infrared, and in a second configuration whereby the lamp is illuminated when the ambient light level is below a predetermined threshold level and when the bypass means is operative to bypass the PIR sensor.

The means for determining an ambient light level may comprise an ambient light sensor, such as a photodetector and/or a clock.

The means for determining an ambient light level may further comprise a means for determining a location of the lighting apparatus.

The bypass means may comprise a manually operable switch arranged to short-circuit the PIR sensor.

The bypass means may comprise a time-controlled switch for supplying power to the lamp at predetermined times of day.

The means for determining an ambient light level and the bypass means may be formed by: a clock for holding the current time and date; a switch for supplying power to the illumination source; and a microprocessor which is configured to toggle the switch in line with the first and second configurations based on the time and date held in the clock.

The lighting apparatus may further comprise means for calculating the times of day when the sun rises and sets, based on a location of the lighting apparatus.

The means for calculating the times of day may include means for setting the location of the lighting apparatus.

The means for setting the location of the lighting apparatus may include a global positioning system receiver.

The clock may include a perpetual Jewish calendar.

The invention will now be described by way of example with reference to the drawings, in which:

Figure 1 is a schematic block diagram of a lighting apparatus forming a first embodiment of the invention;

Figure 2 is a schematic block diagram of a lighting apparatus forming a second embodiment of the invention; and

Figure 3 is a schematic block diagram of a lighting apparatus forming a further embodiment of the invention.

Figure 1 is schematic block diagram of a lighting apparatus 100 forming a first embodiment of the invention. The lighting apparatus 100 comprises a lamp 102, a photodetector 104 and a passive infrared (PIR) sensor 106. The lamp 102 may be an incandescent bulb, such as a linear halogen bulb, an LED array or any other type of illumination source. The lamp 102 is connected in series with the photodetector 104 and the PIR sensor 106. These components 102, 104, 106 are further connected in series with terminals 108 for connection to a power source, such as a mains power supply 110, which is shown in a broken-lined box in the Figure. The lamp 102, photodetector 104, PIR sensor 106 and power terminals 108 are enclosed within a housing (not shown). Windows/apertures are provided in the housing through which these components 102, 104, 106, 108 are accessible to the exterior of the housing.

The lighting apparatus 100 further includes a switch 112 which is in parallel with the PIR sensor 106. The switch 112 may be mounted on the exterior of the housing to allow access by a user. Alternatively, instead of the switch 112 being mounted on the exterior of the housing, the housing may be provided with terminals for connecting a remote switch. For example, cables may be connected from the terminals on the housing to the interior of a building where a switch may be located. Alternatively, there may be no terminals accessible from the exterior of the housing and instead a remote switch 112 may be wirelessly connected to the apparatus 100 so as to provide for flexible location of the switch 112.

In use, the lighting apparatus 100 is configured to operate in one of two modes of operation. In a first mode of operation the switch 112 is open so that the lamp 102 is only illuminated when both the photodetector 104 and the PIR sensor 106 are triggered. The photodetector 104 is triggered to allow illumination of the lamp 102 when the ambient light level in the region of the photodetector 104 is below a predetermined threshold level. As is known in the art, means may be provided for the user to adjust this threshold level. As will be understood by a person skilled in the art, the object of using the photodetector 104 is so that the lamp 102 will only be illuminated when it is dark outside and will not be illuminated during the day.

The PIR sensor 106 detects the presence of a body emitting infrared, such as a human or animal. As for the photodetector 104, the sensitivity of the PIR sensor 106 may be varied in order to vary the detection field of the PIR sensor 106. The function of the PIR sensor 106 is to activate the lamp 102 when a person or animal passes in front of the lighting apparatus 100.

It will be understood by a person skilled in the art that the combined function of the photodetector 104 and the PIR sensor 106 is that lamp 102 will only be illuminated during the night (or at least after the ambient light level has fallen below the predetermined threshold level for the photodetector 104 to be triggered) when a person or animal passes in front of the lighting apparatus 100. The lighting apparatus is also provided with a timer so that when the lamp 102 is illuminated for a predetermined interval before being extinguished. The lighting apparatus 100 may be provided with means for varying this time interval.

In the second configuration, the lighting apparatus 100 is configured so that the lamp 102 is illuminated when the ambient light level is below a predetermined threshold, irrespective of whether a body is detected within the detection field of the PIR sensor 106. This is achieved by manually closing the switch 112, thereby overriding or bypassing the PIR sensor 106. In this second mode of operation, the lighting apparatus 100 is configured to illuminate the lamp only when the ambient light level drops below a predetermined threshold level. In other words, the lamp 102 would be illuminated at all times during the night. The lighting apparatus 100 can be set to operate in accordance with the second configuration by a user who wishes to operate the lighting apparatus 100 in accordance with Jewish law, such that on a Friday afternoon before the commencement of the Jewish Sabbath the switch 112 is closed to disable the PIR sensor 106 and on Saturday evening after termination of the Sabbath the switch 112 is opened to return the lighting apparatus 100 to its first mode of operation.

Figure 2 is a schematic block diagram of a lighting apparatus 200 forming a second embodiment of the invention. As with the lighting apparatus 100 of Figure 1, the lighting apparatus 200 comprises a lamp 102, a PIR sensor 106 and terminals 108 for a power source 110, such as a mains power supply. In contrast to the embodiment of Figure 1, the lighting apparatus 200 does not include a photodetector. The lighting apparatus 200 further comprises a microprocessor 202 (including non-volatile and volatile memory), a clock 204 and global positioning system (GPS) receiver 206. As is explained below, in the lighting apparatus 200 the PIR sensor 106 is bypassed automatically under microprocessor 202 control, rather than by the use of a manual switch 112, as in the first embodiment.

The PIR sensor 106, the clock 204 and the GPS receiver 206 are all connected to the microprocessor. In addition, the terminals 108 for the power supply 110 and the lamp 102 are also connected to the microprocessor 202 in order that the microprocessor 202 controls a power circuit for activating the lamp 102.

The clock 204 holds the current time and date, including the day of the week. The GPS receiver 206 is used to determine the location of the lighting apparatus 200. By considering the date and the location the microprocessor 202 is able to calculate the time of day when it will get dark in the evening and the time of day when it will get light in the morning. This information can be calculated either be applying known algorithms based on the longitude and latitude at which the apparatus 200 is located or by referring to a library of times for different locations stored in the memory of the microprocessor 202. Such data is readily available, for example at the urls www.gaisma.com and www.timeanddate.com/worldclock/sunrise.html.

In a first configuration, the PIR sensor 106 and the microprocessor 202 function to operate the lighting apparatus 200 in a similar manner as the lighting apparatus 100 of Figure 1, whereby the lamp 102 is illuminated when the microprocessor 202 determines, based on the times of dusk and dawn, that the ambient light level is below a predetermined threshold level and the PIR sensor 106 detects the presence of a body emitting infrared.

By using the time and date information the microprocessor 202 is able to operate the lighting apparatus 200 in a second configuration whereby the lamp 102 is illuminated when the ambient light level is below a predetermined threshold level, based on the calculation of dawn and dusk undertaken by the microprocessor 202, and the PIR sensor 106 is bypassed so that the lamp 102 will be illuminated during the night and deactivated in the morning. This mode of operation is based on the date information, whereby the microprocessor 202 operates the lighting apparatus 200 according to the second configuration between dusk on Friday and nightfall on Saturday. As is explained below, the microprocessor 202 also operates according to the second configuration during Jewish holidays.

It is noted that on a Saturday evening the Sabbath does not terminate until nightfall, and it may be desirable for the lamp 102 to be illuminated before the Sabbath has terminated. Hence, once it begins to get dark on a Saturday evening the lighting apparatus 200 will operate in accordance with the second configuration. However, after nightfall on Saturday evening and the termination of the Sabbath the restrictions on creative labour are lifted and at that point the apparatus 200 can once again operate in accordance with the first configuration. In other words, on a Saturday evening (and on the evening at the end of Jewish Holiday) the lamp 102 will be illuminated initially in accordance with the first configuration and will subsequently in accordance with the second configuration. A further enhancement of this second mode of operation is as follows. As stated above, the Jewish Sabbath and Holidays commence at sunset, when active use of lights becomes prohibited. It may not be sufficiently dark at sunset to warrant the turning on of the lamp 102 at the time calculated as sunset, rather the microprocessor 202 may control the lamp 102 to turn it on only at a later time, for example half an hour or an hour after sunset. Hence, rather than the microprocessor 202 causing the lamp to be illuminated close to sunset (which is at a specific time of day) the apparatus 200 can be configured to illuminate the lamp 102 near to sunset, at some point during dusk (which is understood to be the period of the day when it begins to get dark). In addition, during the summer when sunset is later in the evening it is customary for the Sabbath to commence whilst it is still broad daylight. For example, in London during June the sun does not set until after 9pm, whereas many Jewish communities will commence their Sabbath observance earlier than this (typically between 7pm and 7.30pm). It is apparent, therefore, that on a Friday afternoon in the summer the time at which the microprocessor 202 will cause the illumination of the lamp 102 will be later than the time when the Sabbath commences. In other words, the choice of operating the lighting apparatus 200 in the first or second configuration is based on the ambient light level and the day of the week and not directly on the time of commencement and termination of the Jewish Sabbath or Holidays.

Since the clock 204 and the GPS receiver 206 are used to determine the times of day when it gets dark and light, then no photodetector 104 is required in the second embodiment, thereby reducing the cost of this embodiment.

In an alternative embodiment, instead of the lighting apparatus 200 including a GPS receiver 206, the microprocessor 202 can be programmed to record the location of the lighting apparatus 200 prior to installation. This may be undertaken, for example, by connecting the lighting apparatus 200 to a portable or fixed computing device and by storing in the memory associated with the microprocessor 202 a location where the lighting apparatus 200 will be installed. The microprocessor 202 of the lighting apparatus may be connected to the computing device by a wired or wireless connection.

Alternatively, the location where the lighting apparatus 200 will be installed can be pre-programmed in the memory associated with the microprocessor 202 by using jumpers to denote an area or region where the apparatus 200 is being installed. It is anticipated that different models of lighting apparatus will be required for different countries based on local electrical standards. For example, a model of the lighting apparatus may be produced for use solely in the UK. Jumpers may be used for this model to set the region within the UK where the apparatus will be installed. For example, by providing up to three jumpers seven different regions within the UK may be set in addition to a default setting applicable to UK in general, for example by leaving all of the jumper terminals open. By using such jumpers so select a region, the variance of sunset and sunrise will be minimal within such a demarcation, thereby eliminating the need for precise setting of the location using the sensitivity available via a GPS receiver 206.

Figure 3 is a schematic block diagram of a lighting apparatus 300 forming a further embodiment of the invention. The difference between the lighting apparatus 200 of Figure 2 and the lighting apparatus 300 of Figure 3 is that instead of using a GPS receiver 206 the lighting apparatus 300 comprises a photodetector 104. Hence, the lighting apparatus 300 is not ‘aware’ of its location and relies on the ambient light level to determine the onset of night. Nevertheless, by using the time and date information stored in the clock 204 the microprocessor 202 is able to determine whether to operate the lighting apparatus 300 in accordance with the first or second configurations. In other words, the microprocessor 202 determines based on the current time and date that it is not the Jewish Sabbath or a Jewish holiday and illuminates the lamp 102 when triggered by the outputs of the PIR sensor 106 and photodetector 104; and when the microprocessor 202 determines based on the current time and date that it is the Jewish Sabbath or a Jewish holiday then the microprocessor 202 causes the lamp 102 to be illuminated when triggered by the output of the photodetector 104 (and irrespective of the output of the PIR sensor 106).

In the embodiments of Figures 2 and 3 the clock 204 tracks the date, including the day of the week. Using the information about the day of the week the microprocessor 202 is able to determine when the Jewish Sabbath occurs and operate the lighting apparatus 200, 300 in accordance with the first or second configuration. The clock 201 further includes a perpetual Jewish calendar. This calendar includes information about the dates of Jewish holidays when creative labour is prohibited. For example, this information includes the dates of Rosh Hashanah, the Jewish New Year, as 25 and 26 September 2014; 14 and 15 September 2015; 3 and 4 October 2016; 21 and 22 September 2017 etc. (This information is widely available, for example, from http://www.chabad.org/calendar/view/month.htm.) By referring to the dates of Jewish holidays stored in the perpetual Jewish calendar in the clock 204 the microprocessor 202 is similarly able to determine when to operate the lighting apparatus 200, 300 in the second configuration.

Various modifications will be apparent to those in the art and it is desired to include all such modifications as fall within the scope of the accompanying claims.

For example, when referring to a photodetector 104, it is apparent that any device for detecting ambient light levels may be used, such as photodiodes, image sensors, photoresistors, phototransistors, photovoltaic cells etc.

Claims

1. A lighting apparatus comprising: a lamp for illuminating an exterior location; means for determining an ambient light level; a passive infrared, PIR, sensor for detecting the presence of a body emitting infra red; and bypass means for bypassing the PIR sensor, wherein the apparatus is configured to operate: in a first configuration whereby the lamp is illuminated when the ambient light level is below a predetermined threshold level and the PIR sensor detects the presence of a body emitting infrared, and in a second configuration whereby the lamp is illuminated when the ambient light level is below a predetermined threshold level and when the bypass means is operative to bypass the PIR sensor.

2. A lighting apparatus as claimed in claim 1, wherein the means for determining an ambient light level comprises an ambient light sensor.

3. A lighting apparatus as claimed in claim 2, wherein the ambient light sensor is a photodetector.

4. A lighting apparatus as claimed in claim 1, wherein the means for determining an ambient light level comprises a clock.

5. A lighting apparatus as claimed in claim 4, wherein the means for determining an ambient light level further comprises a means for determining a location of the lighting apparatus.

6. A lighting apparatus as claimed in any one of the preceding claims, wherein the bypass means comprises a manually operable switch arranged to short-circuit the PIR sensor.

7. A lighting apparatus as claimed in any one of claims 1 to 5, wherein the bypass means comprises a time-controlled switch for supplying power to the lamp at predetermined times of day.

8. A lighting apparatus as claimed claim 1, wherein the means for determining an ambient light level and the bypass means are formed by: a clock for holding the current time and date; a switch for supplying power to the illumination source; and a microprocessor which is configured to toggle the switch in line with the first and second configurations based on the time and date held in the clock.

9. A lighting apparatus as claimed in claim 8, further comprising means for calculating the times of day when the sun rises and sets, based on a location of the lighting apparatus.

10. A lighting apparatus as claimed in claim 9, wherein the means for calculating the times of day includes means for setting the location of the lighting apparatus.

11. A lighting apparatus as claimed in claim 10, wherein the means for setting the location of the lighting apparatus includes a global positioning system receiver.

12. A lighting apparatus as claimed in any one of claims 4, 5 and 8 to 11, wherein the clock includes a perpetual Jewish calendar.