WO2010079398A1

WO2010079398A1 - Lighting control system with wireless sensor

Info

Publication number: WO2010079398A1
Application number: PCT/IB2009/055863
Authority: WO
Inventors: Roger P. A. Delnoij
Original assignee: Koninklijke Philips Electronics N.V.
Priority date: 2009-01-06
Filing date: 2009-12-21
Publication date: 2010-07-15
Also published as: TW201031269A

Abstract

The invention according to the present invention relates to a lighting control system comprising at least one sensor, a control unit to control a power supply to a lighting system in dependency of signals provided by the sensor, a linking system for linking the sensor to the control unit, enabling the sensor and the control unit to wirelessly communicate with each other, and an attachment assembly for attaching the sensor to an object at a place of attachment thereof, wherein the attachment assembly is configured to detach the sensor from the object by hand, and to attach the sensor to the object again by hand.

Description

LIGHTING CONTROL SYSTEM WITH WIRELESS SENSOR

FIELD OF THE INVENTION

The invention relates to the field of a lighting control system, and more specifically to a lighting control system that can be retrofitted into a building.

BACKGROUND OF THE INVENTION

Energy saving is globally seen as vital for our environment. Automated control of lighting can provide substantial energy saving within homes and buildings by measuring the occupancy of rooms and/or measuring the light level.

To allow energy saving in existing buildings as well, an automated lighting control system can be retrofitted into such a building. This may imply that an old wall switch is replaced by a control unit interacting with a sensor that measures the occupancy of a room and/or the light level. The installation costs are currently a large portion of the total costs, and therefore wireless sensors are proposed to reduce these costs.

As the wireless sensor is not directly connected to the control unit, the sensor has to be linked to the control unit, thereby enabling the sensor and the power control unit to wirelessly communicate with each other. Most linking procedures require that the sensor and the control unit are brought in close proximity to each other. Because of a possible limited linking range, other nearby control units may interfere with the linking procedure, or direct contact is required between sensor and control unit. In this case it is required that the sensor is installed after the sensor is linked to the control unit. If by mistake the sensor is installed before linking the sensor to the control unit, this error has to be corrected by first uninstalling the sensor, then linking the sensor to the control unit and subsequently installing the sensor again, which is time-consuming.

An additional disadvantage may be that the placement of the sensor is ideally when the sensor is placed nearby the area of the detection, for example above a desk. When the desk is moved in a space, it is possible that the sensor becomes less effective in detecting the occupancy of the space. As a result, it may become desirable to uninstall the sensor and install the sensor at another place of attachment. SUMMARY OF THE INVENTION

It would be desirable to provide a lighting control system with a more flexible installation procedure. It would also be desirable to reduce the installation costs of a lighting control system. To better address one or more of these concerns, in a first aspect of the invention a lighting control system is provided comprising at least one sensor, a control unit to control a power supply to a lighting system in dependency of signals provided by the sensor, a linking system for linking the sensor to the control unit, enabling the sensor and the control unit to wirelessly communicate with each other, and an attachment assembly for attaching the sensor to an object at a place of attachment thereof, wherein the attachment assembly is configured to detach the sensor from the object by hand, and to attach the sensor to the object again by hand.

In another aspect, the present invention provides a method for linking a sensor of a lighting control system described above to a control unit by using the linking system, the method comprising : a) optionally, detaching the sensor by hand from the object; b) transmitting a linking signal from the sensor; c) receiving the linking signal by all nearby control units, and transmitting a response signal from all nearby control units to the sensor; d) receiving the respective response signals by the sensor; e) determining the signal strength of each received response signal by the sensor; f) linking the sensor to the control unit that transmitted the response signal with the highest signal strength; and g) attaching the sensor to the object by hand.

These and other aspects of the invention will be more readily appreciated as the same becomes better understood by reference to the following detailed description and considered in connection with the accompanying drawings in which like reference symbols designate like parts.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 depicts a schematic view of a lighting control system according to an embodiment of the invention. Figure 2 depicts a schematic view of a lighting control system according to another embodiment of the invention.

Figures 3 A and 3B depict a schematic representation of a sensor SE3 in a detached position and an attached position respectively.

DETAILED DESCRIPTION OF EMBODIMENTS

Figure 1 depicts a schematic view of a lighting control system LCS comprising at least one sensor SE, a control unit CU to control a supply of power PO to a lighting system LI in dependency of signals provided by the sensor SE, a linking system LS for linking the sensor SE to the control unit CU, enabling the sensor SE and the control unit CU to wirelessly communicate with each other, and an attachment assembly AT for attaching the sensor SE to an object OB at a place of attachment thereof, wherein the attachment assembly AT is configured to detach the sensor SE from the object OB by hand, and to attach the sensor SE to the object OB again by hand. The wireless communication between the sensor SE and the control unit CU is represented by arrow WS.

The lighting system may comprise lights or a plurality of lights, but may also comprise sun blinds, heating systems, ventilation systems, or air-conditioning systems and the like. In that case, the power and drive signals to these systems are also controlled by the control unit CU. The lighting control system LCS may be installed into a building where the object OB, the lighting system LI, and an electric mains EM are already present. The control unit CU will then most of the time replace an old wall switch, because connections PI and PO to the electric mains EM and the lighting system LI respectively are already present there. The electric mains EM is able to provide power PI to the control unit CU and will supply the power PO to the lighting system LI. The control unit CU controls the amount of power PO that is supplied to the lighting system LI. The control unit CU may function as an on/off switch, thereby allowing no power or full power to the lighting system LI. It is also possible that the control unit CU functions as a dimmer, wherein intermediate power levels can be supplied to the lighting system LI as well. In a variant, it is also possible that the control unit CU provides drive signals to the lighting system LI as well, thereby controlling sun blinds and/or other systems.

The power control supply unit CU controls the power supply to the lighting system LI in dependency of signals provided by the sensor SE. The sensor SE may be configured to measure the occupancy of a space and/or a light level in the space. The occupancy of the space can be measured by using motion detectors.

In case of measuring the occupancy of a space, the lighting control system LCS may be configured to supply power to the lighting system LI in case the space is occupied. When the sensor SE also measures the light level inside the space, the lighting control system LCS may be configured to supply power to the lighting system LI only when the space is occupied and the (natural) light level is below a certain threshold. Other configurations and sensors are also possible, depending on the requirements of the space. The sensor SE and the control unit CU communicate wirelessly with each other, thereby allowing an easy installation of the light control system LCS, because no wiring between the sensor SE and the control unit CU need to be installed.

The linking system LS in this embodiment is associated with the sensor SE only. Other configurations of the linking system LS are also possible, as will be explained below. The linking system LS links the sensor SE to the control unit CU, thereby enabling the wirelessly communication with each other. It is possible that the linking system LS links the sensor to more than one control unit CU, thereby allowing wireless communication with more than one control unit CU. This can be advantageous when due to a large space and/or a lighting system with multiple lights, a plurality of control units CU are required to control the lighting system LI, but only one sensor suffices, or a lesser number of sensors than the number of lighting systems suffices.

In the embodiment shown, the linking system LS is associated with the sensor SE, thereby indicating that no active role of the control unit CU is required to link the sensor SE to the control unit CU. Examples of such a linking system LS are a bar code reader or a linking system LS wherein a person can manually enter an identification code to link the sensor SE to the control unit CU. It is also possible that the linking system LS has to directly contact the control unit CU to extract an identification that allows the linking system to link the sensor SE to the control unit CU, or that buttons on the sensor SE and control unit CU are pressed sequential within a time-slot to form the link.

The attachment assembly AT is arranged to attach the sensor SE to the object OB at a place of attachment thereof. The object OB can be any object in a space, but is preferably a wall or ceiling of the space. However, other objects, such as furniture or lamps are also envisaged. The attachment assembly is further configured to detach the sensor SE from the object OB by hand and to attach the sensor SE to the object OB again by hand. This is schematically shown by arrow HA in Figure 1. In view of the linking between the sensor SE and the control unit CU, it is unimportant in which order the sensor SE and the control unit CU are installed. After installation of both devices, an installer can easily link the sensor SE to the control unit CU by detaching the sensor SE from the object OB by hand, link the sensor SE to the control unit CU and attach the sensor SE to the object OB again by hand. If required, this procedure can be repeated to link the sensor SE to another control unit CU. The easy handling of the sensor SE thus allows a flexible installation procedure and reduces the installation time, resulting in reduced installation costs.

An additional advantage of the easy handling of the sensor SE is in case the sensor is battery powered and the battery needs to be replaced, a person can easily detach the sensor SE from the object OB, replace the battery, and attach the sensor to the object OB again by hand. Other situations wherein the sensor SE needs to be temporarily detached from the object OB can also use this advantage.

The attachment assembly AT is configured to detach the sensor SE from the object OB by moving the sensor SE away from the place of attachment. This only requires one simple act to detach the sensor SE and will thus be efficient. The attachment assembly AT is configured such that the reverse operation is also possible. The sensor SE can then also be attached to the object OB by moving the sensor SE to the place of attachment, thereby only requiring one simple act to attach the sensor, which is efficient. Moving the sensor SE away from, or to the place of attachment to respectively detach or attach the sensor SE to the object OB can be done when the attachment assembly AT comprises at least one magnet and a part comprising a magnetizable material. The magnet may form part of a housing of the sensor SE, for instance be part of an outer surface of the housing or be located near an outer surface of the housing, or may be attached to the object OB. In case the magnet is part of the sensor SE, the part comprising the magnetizable material will be attached to the object OB. In case, the magnet is attached to the object OB, the part comprising the magnetizable material is part of the sensor SE.

The magnet is preferably a permanent magnet, and can be a neodymium magnet. The part comprising the magnetizable part can be any kind of attachment means, such as screws, Parker type screws, bolts, nails, etc.

It is also possible that the object OB itself comprises a part having magnetizable properties. In that case, the sensor SE comprises a magnet to engage with the part of the object OB. In a variant, the attachment assembly AT comprises two interacting Velcro components instead of a magnetic assembly.

Figure 2 depicts a schematic view of a lighting control system LCS2 according to another embodiment of the invention. The working principle of this embodiment is similar to the embodiment of Figure 1 and will de described in short hereinafter.

The lighting control system LCS2 comprises a control unit CU2 to control a power supply PO2 from an electric mains EM2 to a lighting system LI2. The power supplied by the electric mains is represented by arrow PI2. The control unit CU2 controls the power supply in dependency of signals provided by a sensor SE2. The lighting control system further comprises an attachment assembly AT2 for attaching the sensor SE2 to an object OB2 at a place of attachment thereof. The attachment assembly AT2 is configured to detach the sensor SE2 from the object OB2 by hand and to attach the sensor SE2 to the object OB2 again by hand, indicated by arrow HA2. So far, the embodiment of Figure 2 is similar to the embodiment of Figure 1. The variants and possibilities shown for the embodiment of Figure 1, may thus also apply for this embodiment. From a schematic point of view, the embodiment according to Figure 2 differs from the embodiment according to Figure 1 , in that a linking system LS2 has a portion LS2A associated with the sensor SE2, and a portion LS2B associated with the control unit CU2. The linking system LS2 is able to link the sensor SE2 to the control unit CU2, enabling the sensor SE2 and the control unit CU2 to wirelessly communicate with each other, as is indicated by arrow WS2.

Whereas in the embodiment of Figure 1, the linking system LS is associated with only the sensor SE and therefore no action was required from the control unit CU to link the sensor SE to the control unit CU, the linking system LS2 is associated to both the sensor SE2 and the control unit CU2, thereby indicating that a linking procedure requires action both from the sensor SE2 and from the control unit CU2.

In a variant, when commencing the linking procedure, the portion LS2A can transmit a linking signal. In response to the linking signal, portion LS2B may transmit a response signal, thereby linking the sensor SE2 to the control unit CU2. In case a plurality of control units CU2 are present nearby, it is not always desired to link the sensor SE2 to each of the control units CU2. In another variant, it is therefore possible to link the sensor SE2 to a nearest control unit CU2 by comparing the signal strength of the plurality of control units CU2. It may therefore be desirable to detach the sensor SE2 from the object OB2 and hold the sensor SE2 close to the control unit CU2 with which the sensor has to be linked.

A method for linking the sensor SE2 to a control unit CU2 by using the linking system LS2 may comprise the following steps: a) optionally, detaching the sensor SE2 from the object OB2. This step is not always necessary in case the sensor is already detached from the object, or not yet installed; b) transmitting a linking signal from the sensor SE2 by using portion LS2A; c) receiving the linking signal by all nearby control units CU2, and transmitting a response signal from all nearby control units to the sensor SE2 by using portion LS2B. d) receiving the respective response signals by the sensor SE2 using portion

LS2A. e) determining the signal strength of each received response signal by portion LS2A of the sensor SE2. f) linking the sensor SE2 to the control unit CU2 that transmitted the response signal with the highest signal strength. g) attaching the sensor to the object OB2 by hand.

If the sensor SE2 has to be linked to another control unit CU2, the steps b) to f) can be repeated before step g) is performed. Portion LS2A of the linking system LS2 may comprise a manually operable link switch to commence the linking procedure. The steps b) to f) are than automatically performed after manually operating the link switch.

Portion LS2A of the linking system LS2 may further comprise a manually operable reset switch for erasing an existing link, preferably all existing links, between the sensor SE2 and respective control units CU2. When the portion LS2A comprises such a reset switch, the step of erasing existing links between the sensor SE2 and a control unit CU2 may be performed before commencing the steps b) to f).

This allows for a flexible system, which is able to link a sensor with a chosen control unit and change the linking scheme if required. Also, if errors occur during installation, the existing links can be simply erased to start linking correctly.

In a variant, it is possible that the link switch and/or reset switch are located on the portion LS2B and that the linking signal is transmitted by the portion LS2B, in which case, the linking procedure will be altered so that portion LS2B transmits the linking signal and receives the respective response signals from nearby sensors, and portion LS2A will receive the linking signal and transmit a response signal. The portion LS2B will then determine the highest signal strength. Also in this case, the mobility of the sensor SE2 due to the configuration of the attachment assembly AT2 allows a flexible and easy to handle system while linking the sensor SE2 to the control unit CU2. It is noted that the linking signal can be any kind of signal, examples are infrared and RF signals, but other signal types are also envisaged. The same applies to the communication protocol.

Figures 3 A and 3B depict a schematic representation of a sensor SE3 in a detached position (Figure 3A) and an attached position (Figure 3B). The sensor SE3 comprises a housing HO and in this embodiment two detectors DEl and DE2, although an embodiment with only one detector is also possible. The detectors DEl and DE2 can be motion detectors to measure the occupancy of a space, or can be light level detectors. A mixture of two types of detectors is also possible.

The sensor further comprises an attachment assembly, comprising a permanent magnet MA and a Parker type screw PS comprising a magnetizable material. The Parker type screw is screwed into an object OB3, which can be a ceiling, a wall or any other object in the space. In a preferred embodiment, the Parker type screw PS is screwed into the object OB3 such that the head of the screw PS levels with the surface of the object OB3. In that case, the magnet MA will engage the Parker type screw PS, and the sensor SE3 will engage the surface of the object OB3, thereby resulting in a stable attachment. The Parker type screw PS comprises a relatively large flat surface to which a magnet MA can be magnetically coupled.

The magnet MA is preferably a neodymium permanent magnet, but an electromagnet is also envisaged. The magnet in this embodiment forms part of an outer surface of the housing HO, but it can also be near the outer surface of the housing HO. If the weight of the sensor SE3 is less than 350 grams, a small neodymium magnet of 5x5 mm and lmm height can suffice to bear the weight of the sensor SE3.

The screw PS comprises magnetizable material, so that the magnet MA can apply magnetic forces between the magnet MA and the screw PS. The magnetic force between the magnet MA and the screw PS is dependent on the distance between the magnet MA and the screw PS.

In Figure 3 A, the sensor SE3 is in a detached position, wherein the magnetic forces are not strong enough to hold the weight of the sensor SE3. The sensor SE3 can be attached to the object OB3 by moving the sensor SE3 to the place of attachment, that is, to the Parker type screw PS. With a smaller distance between the magnet MA and the screw PS, the magnetic forces are bigger, and from a certain distance on, the forces are able to hold the weight of the sensor SE. The sensor SE3 is then in an attached position as shown in Figure 3B.

Starting from the attached position as shown in Figure 3B, the sensor can be detached from the object OB3 by moving the sensor SE3 away from the place of attachment, that is, away from the Parker type screw PS. As the distance grows between the Parker type screw PS and the magnet MA, the magnetic forces will decrease.

It is noted, that detaching and attaching the sensor SE3 can be done by moving the sensor SE3 in any direction. In Figures 3A and 3B a vertical direction is shown, but it can also be a transverse direction.

The sensor SE3 further comprises a link switch LIS and a reset switch RS that are manually operable. Manually operating the link switch LIS will start a linking procedure as described above, and manually operating the reset switch RS will erase an existing link between the sensor SE3 and a control unit. An additional advantage of the embodiments of Figure 3 A and 3B is that the installation of the sensor is simplified as well. If for instance, the sensor is placed above a desk to detect the occupancy of a space, and the desk is moved, it is possible that the sensor becomes less effective. The simple installation now enables to quickly uninstall the sensor and install the sensor again at an optimized place of attachment thereof. As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting, but rather, to provide an understandable description of the invention.

The terms "a" or "an", as used herein, are defined as one or more than one. The term plurality, as used herein, is defined as two or more than two. The term another, as used herein, is defined as at least a second or more. The terms including and/or having, as used herein, are defined as comprising (i.e., open language, not excluding other elements or steps). Any reference signs in the claims should not be construed as limiting the scope of the claims or the invention. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

The term coupled, as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically.

Claims

CLAIMS:

1. A lighting control system comprising: at least one sensor; a control unit to control a power supply to a lighting system in dependency of signals provided by the sensor; - a linking system for linking the sensor to the control unit, enabling the sensor and the control unit to wirelessly communicate with each other, and an attachment assembly for attaching the sensor to an object at a place of attachment thereof, wherein the attachment assembly is configured to detach the sensor from the object by hand, and to attach the sensor to the object again by hand.

2. The lighting control system according to claim 1, wherein the attachment assembly is configured to detach the sensor from the object by moving the sensor away from the place of attachment.

3. The lighting control system according to claim 1 or 2, wherein the attachment assembly is configured to attach the sensor to the object by moving the sensor to the place of attachment.

4. The lighting control system according to any of claims 1-3, wherein the attachment assembly comprises at least one magnet and a part comprising a magnetizable material.

5. The lighting control system according to claim 4, wherein the magnet is a permanent magnet.

6. The lighting control system according to claim 5, wherein the magnet is a neodymium magnet.

7. The lighting control system according to any of claims 4-6, wherein the part comprises at least one screw to be screwed into the object, and wherein the sensor comprises the magnet.

8. The lighting control system according to claim 7, wherein the screw is a

Parker type screw.

9. The lighting control system according to any of claims 4-8, further comprising a housing for accommodating the sensor, and wherein the magnet is part of an outer surface of the housing.

10. The lighting control system according to any of claims 4-8, further comprising a housing for accommodating the sensor, and wherein the magnet is located near an outer surface of the housing.

11. The lighting control system according to any of claims 1-10, comprising a plurality of control units at different distances from the sensor when linking the sensor to a control unit, and wherein the linking system is configured to link the sensor to a nearest control unit by comparing the signal strength of the plurality of control units and linking the sensor to the control unit having the highest signal strength.

12. The lighting control system according to any of claims 1-11, wherein the linking system comprises a manually operable link switch to commence a linking procedure for linking the sensor to the control unit.

13. The lighting control system according to any of claims 1-12, wherein the linking system comprises a reset switch for erasing an existing linking between the sensor and the control unit.

14. The lighting control system according to any of claims 1-13, wherein the sensor is powered by a battery.

15. The lighting control system according to any of the claims 1-13, wherein the sensor is powered by a photovoltaic cell.

16. A method for linking a sensor of a lighting control system according to any of the claims 1-15 to a control unit by using the linking system, the method comprising: a) optionally, detaching the sensor by hand from the object; b) transmitting a linking signal from the sensor; c) receiving the linking signal by all nearby control units, and transmitting a response signal from all nearby control units to the sensor; d) receiving the respective response signals by the sensor; e) determining the signal strength of each received response signal by the sensor; f) linking the sensor to the control unit that transmitted the response signal with the highest signal strength; and g) attaching the sensor to the object by hand.

17. The method according to claim 16, wherein steps b) to f) are repeated before step g) is performed.

18. The method according to claim 16 or 17, further comprising the step of erasing existing links between the sensor and a control unit before performing step b).

19. The method according to any of claims 16-18, wherein steps b) to f) are automatically performed after manually operating a link switch.