Power outlet socket sensor switch

Abstract

A mains electrical power outlet assembly; said power outlet assembly including at least one power outlet socket; said power outlet assembly including at least one sensing module, operating a power switching module and a microprocessor; said sensing module including a sensor responsive to proximity to said sensor of selected objects; proximity of a said selected object switching status of a said power outlet socket from a current state to another state.

Claims

1. A mains electrical power outlet assembly; said power outlet assembly including at least one power outlet socket adapted to receive a plug of an electrical appliance or electrical extension cord; said power outlet assembly including at least one sensing module operating a power switching module and a programmable and reprogrammable microprocessor; said sensing module including a sensor responsive to proximity to said sensor of selected objects; proximity of a said selected object switching status of a said power outlet socket from a current state to another state; and wherein said at least one power outlet socket is switched to a locked deactivated state if a sensible object remains within sensing distance of an associated said sensor of said at least one power outlet socket for at least a first predetermined duration; said locked deactivated state being reversed to an activated state when a said sensible object is maintained within said sensing distance of said associated sensor for at least a second predetermined duration, wherein said assembly includes an infrared transmitter and receiver module; said module adapted to receive programming data via an infrared data stream from a remote infrared data transmitter; said data stream passing to said module via a light guide provided between an upper rim of a face plate of said assembly and said module.

2. The power outlet assembly of claim 1 wherein said assembly is provided with an automatic dimming of light emitters; said light emitters indicating status of power switches of said assembly; an ambient light sensor reacting to ambient light at a switch assembly; said ambient light sensor receiving ambient light input via a light guide provided between said upper rim of said face plate of said assembly and said ambient light sensor.

3. The power outlet assembly of claim 1 wherein said assembly includes an internal load in series with at least one conductor and wherein a voltage drop across said internal load is utilised to provide power to said microprocessor during at least a portion of the operating cycle of the power switching module.

4. An electrical switch assembly for switching the state of at least one conductor of a mains alternating power supply; said electrical switch assembly including a housing containing a sensing module and a power switching module; said switch assembly characterized in that electrical power switched by said switch assembly is mains alternating power; said switch assembly including a microprocessor in communication with the sensing module and the power switching module for switching the state of the at least one conductor; said assembly including an internal load in series with said at least one conductor and wherein a voltage drop across said internal load is utilised to provide power to said microprocessor during at least a portion of the operating cycle of the switch assembly, wherein the power switching module includes a relay and the assembly utilises voltage drop across terminals of the relay of the power switching module to provide power to said microprocessor.

5. The assembly of claim 4 wherein the assembly utilises voltage drop across a plurality of relay terminals of the power switching module to provide power to said microprocessor as a first choice and utilises the voltage drop across said internal load to provide power to said microprocessor as a second choice.

6. The switch assembly of claim 4 further including an ambient light sensor in communication with the microprocessor; the microprocessor programmed to increase output voltage from the switch assembly as the amount of ambient light sensed by the ambient light sensor reduces thereby to increase the light output from lights supplied by the switch assembly as ambient light decreases.

7. An electrical switch assembly for switching the state of at least one conductor of a mains alternating power supply; said electrical switch assembly including a housing containing a sensing module and a power switching module; said switch assembly characterized in that electrical power switched by said switch assembly is mains alternating power; said switch assembly including a microprocessor in communication with the sensing module and the power switching module for switching the state of the at least one conductor; said assembly including an internal load in series with said at least one conductor and wherein a voltage drop across said internal load is utilised to provide power to said microprocessor during at least a portion of the operating cycle of the switch assembly, wherein the assembly utilises voltage drop across a plurality of relay terminals of the power switching module to provide power to said microprocessor as a first choice and utilises the voltage drop across said internal load to provide power to said microprocessor as a second choice.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) Embodiments of the present invention will now be described with reference to the accompanying drawings wherein:

(2) FIG. 1 is an exploded perspective view of a first preferred embodiment of a switch assembly according to the present invention;

(3) FIG. 2 is a partially sectioned side view of the switch assembly of FIG. 1 mounted in a wall of a building;

(4) FIG. 3 is a front view of a further preferred embodiment of a switch assembly according to the invention;

(5) FIG. 4 is a schematic circuit diagram of the principle components of the switch assembly of FIGS. 1 to 4;

(6) FIG. 5 is a schematic presentation of a number of the switch assemblies of FIGS. 1 to 3 arranged for intermediate switching;

(7) FIG. 6 is a schematic sectioned view of a power switch assembly according to the invention provided with an ambient light sensing facility;

(8) FIG. 7 is schematic sectioned view of the power switch assembly of FIG. 6 further provided with a remote programming facility;

(9) FIGS. 8 to 12 are schematic electronic circuits illustrating a method of powering embodiments of the switching assembly of the invention where there is no direct connection to an AC neutral available locally.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(10) In this specification:

(11) wall plate signifies a plate mounted to a wall or other supporting surface and incorporating one or more power switches or power switches and power outlets.

(12) mounting bracket signifies any one of a number of brackets for recessed mounting in plaster board (or wall board), wood framed walls (stud mounting) or other types of wall construction.

(13) capacitance sensor signifies a proximity sensor based on capacitance coupling effects and reacting to the proximity of a certain range of objects.

(14) RF receiver or transmitter module signifies a Radio Frequency device able to either receive radio signals from a remote device, or transmit radio signals to a remote device.

(15) sensible object is any object which the sensor switch is able to detect and respond to. This may include the human hand or a part thereof such as a finger.

First Preferred Embodiment

(16) With reference to FIGS. 1 and 2, in this first preferred embodiment of the invention, an alternating current, mains power switch assembly generally designated by the numeral 10, comprises an assembly of one or more power switches for operating light sources or other electrical equipment. Switch assembly 10 includes a face plate assembly 12 comprising a transparent front plate 14 mounted to a perimeter frame 16, and a body element 18 comprising a mounting plate 20 and integral housing 22.

(17) Preferably the transparent front plate 14 is of glass and has a rear surface covered with an opaque layer 24. Inscribed in this opaque layer 24 is at least one clear annular circle 26 through which light can pass, for each power switch. The exemplary switch system illustrated in FIG. 1 has two separate switches, but it will be appreciated that the relatively small area required by each switch, allows a standard sized wall plate to accommodate a relatively large number of switches.

(18) The perimeter frame 16 is releasable attached to a perimeter rim 28 of the mounting plate 20 by means of snap-fit elements 30 (only those on the rim 28 being visible in FIG. 1).

(19) The mounting plate 20 and housing 18 are sized and configured to allow mounting in a standard opening 32 in a building wall 34 (such as the plaster or wall board wall 36 shown in FIG. 2), and attachment to light switch and power point mounting brackets 38 standard in the industry. When mounted in a wall or other supporting surface, only the transparent front plate and its perimeter frame 16 project from a wall or other mounting surface, as shown in FIG. 2.

(20) Located immediately behind the rear surface of the transparent front plate 14 is a sensor printed circuit board 40. At least one sensor 42 is mounted to the front surface of the sensor circuit board 40, located so that each sensor 42 is positioned directly behind a corresponding clear annular circle 26 of the transparent front plate 14 when the circuit board 40 is assembled within housing 22, and face plate assembly 12 is attached to the rim 28.

(21) Mounted within the housing 22 itself, is a second or main printed circuit board 44 which carries relays, one or more microprocessor logic chips, circuitry and associated components, as well as wiring terminal blocks 46. In at least some embodiments, as more fully described below, the components may include either or both RF transmitting and RF receiver modules. Connection between the sensor circuit board 40 and the main printed circuit board 44 is by means of a multi-pin plug and socket connector 48.

(22) Sensor or sensors 42 combine the functions of a proximity sensor switch and a light emitter. Preferably the sensor comprises a capacitance sensor provided with an LED backlight. When installed and connected to a power grid in a building, the light emitted by the sensor 42 when the proximity sensor switch is in a deactivated state, defaults to a first colour, for example blue to indicate that the switch is off. When the sensor detects a sensible object brought to within its sensing range and the switch is activated, the light emitted changes to a second colour, for example orange, thereby indicating that the switch is on. A next brief approach by a sensible object returns the switch to the off condition and the emitted colour back to the default first colour.

(23) The sensors 42 of the system are sensitive to a finger brought momentarily into contact with, or passing close to, the outer surface of transparent front plate 14. Such an approach by a finger will thus cause the sensor to activate the switch, tripping the associated relay, (in case of a single pole arrangement), or relays (if a double pole arrangement), allowing current to flow to the light or other device connected to, or controlled by, the switch system 10.

(24) Preferably, the system 10 includes a potentiometer component or dimming element for each switch arrangement to allow dimming of a light source. By a user maintaining a finger within the sensing distance of a sensor, (and after the switch has been triggered to on by a first approach of the finger), the dimming element acts to dim the light source connected to the switch. The dimming is progressive in accordance with the length of time the user keeps the finger within the sensing distance.

(25) The level of dimming is retained in memory so that at the next activation of the light source, the luminescence previously set is reinstated. Holding the finger in the sensing position reverses the dimming towards the maximum luminescence, with the extent of the reversal depending on the length of time the finger is held within the sensing distance. A microprocessor (FIG. 4) controls the logic sequences of switching and dimming, and also controls the operation of the RF receiver and transmitter modules where these are fitted.

Second Preferred Embodiment

(26) In a second preferred embodiment, the switch system 100 controls one or preferably two power outlet sockets 110 as shown in FIG. 3. Each sensor 142 controls an associated power outlet socket mounted within apertures provided in the transparent front plate 114. In this case, with the exception of the dimmer function described above, the sensors, indicating colours, relay or relays switching are as described for the first preferred embodiment above. However, instead of relays controlling a remote light source or other device, the triggering of a sensor switches power to its corresponding power outlet socket either to on or to off. The light emitter changes colour accordingly, again, as described above.

(27) Preferably, circuitry in the present embodiment is responsive to a user's finger remaining within sensing range for longer than a first predetermined length of time. By this means, a power outlet socket may be locked in an off status, when switching from a present on status, or when the switch is already off. In this locked condition, power cannot be switched on by a momentary passing of a finger through the sensing area of the sensor but must be deliberately maintained within the sensing distance of the sensor for a second, longer length of time to re-activate the power outlet socket.

(28) For example, an outlet may be locked into an off status by retaining a finger within the sensing distance for more than five seconds, while the unlocking may require more than ten seconds. In one preferred arrangement, the indicating blue off light may be set to flash at intervals to show the power outlet socket is in the locked off condition.

Third Preferred Embodiment

(29) In a third preferred embodiment of the invention, again the construction, sensing, switching and switch status indication are similar to that described in the first and second preferred embodiments above. In this embodiment however the sensing system activates or de-activates an RF (Radio Frequency) transmitter mounted to the main circuit board or otherwise retained within the housing.

(30) The sensing of a user's finger in this embodiment will cause the RF transmitter to send either an on or off signal pulse to an RF receiver mounted at the light source or other device associated with the switch assembly.

Fourth Preferred Embodiment

(31) In this further preferred embodiment according to the invention, the switch system may incorporate an RF receiver module, either instead of or in addition to, the RF transmitter module of the third embodiment above. By means of an inbuilt RF receiver module, the switch or switches of the switch assembly may be operated from a remote control RF transmitter.

(32) When fitted with both RF receiver and transmitter modules, each switch assembly in a building can be operated wirelessly from some central location or remote control module. In the case of light switches at least, all the lights in a building may be controlled in this manner.

(33) Fitting each switching assembly in an array of switching assemblies with both an RF receiving and an RF transmitting module, allows the switches to communicate intelligently as programmed through their respective microprocessors. By this means one or more light sources or other electrical devices may be controlled from any of the switch assemblies in the array in the manner of a intermediate switching arrangement.

(34) A particular feature of the present invention is the incorporation of at least one microprocessor in each switch assembly. This element provides flexibility in the programming of the switch operation and the response to signals received or the format of transmissions to other switches and RF receiver enabled devices in a building's power distribution system.

(35) In a preferred arrangement, the circuit board of the switch assembly may include an input socket, such as a USB port for example, accessible after removal of the face plate, to enable reprogramming of the switching and any RF module functions.

Further Preferred Embodiments

(36) Automatic Dimming of Switch Status Indicator

(37) With reference now to FIG. 6, in a further preferred embodiment a power switch 200 according to the invention is provided with an ambient light sensing facility. In order to avoid the problem in which the illumination of the light emitter or emitters 42,142 (see FIGS. 1 and 3), which indicate the various functions and status of the switch through rings in the face plate 14,114, is either too bright during the night or too dull during the day, the brightness of the indicators is modulated according to the ambient light at the switch 218.

(38) In a preferred arrangement, this is accomplished as shown in FIG. 6 by placing an ambient light sensor 210 in such a way that it can respond to the ambient light in the room without it being influenced by the light from the indicators 42,142. A light guide 212, for example a fiberoptic bundle, is incorporated partly in the face plate 214 such that its light entry end 216 is located in the upper rim of face plate 214 and leads to the ambient light sensor 210 located within the housing 222.

(39) Ambient light sensor 210 communicates with microprocessor 250 which controls the light issuing from indicator rings 42,142 as described in the embodiments above.

(40) Remote Programming of Switches

(41) With reference to FIG. 7, in a further embodiment of the invention, a light switch 318 is provided with a light guide 312. In one preferred embodiment, this may be the same light guide described for the automatic dimming described above, or may be a second light guide. In this instance the receiving end 316 is again discreetly located at the upper rim of the face plate 316 and leads to an infrared transmitter and receiver 310 located in the housing 322 of the switch 318.

(42) Initial (and any subsequent upgrade) firmware in the microprocessor 350 responds to a specific sequence of data from the infrared receiver by running a bootloader sequence of code. The bootloader 352 is adapted to receive new switch programming code from an external device 340, such as an infrared emitting remote control, and loads the new programming code into non-volatile memory 354. The bootloader and non-volatile memory may be either internal or external to the microprocessor 350.

(43) The external infrared emitting device 340 may in turn be programmed by connection to a computer 360.

(44) Powering Without Neutral

(45) The switch assembly of the present invention relies on a microprocessor and other electronic components. As such it requires a power supply to power its active internal components. Where the switch assembly is being used for switching general-purpose power outlets there is usually an active and neutral available at mains voltage from which power can be drawn and converted to DC utilising a suitable commercially available power supply chip.

(46) Particularly in the case of power switching for lights, the circuit in which the switch assembly is located may not include a neutral connection. Or at least the neutral is only accessible via the load which the switching assembly is intended to control.

(47) With reference to FIGS. 8 to 12 this situation is discussed and a solution provided which permits powering of the active internal components of the switch assembly where no direct connection to neutral is available. In particular forms the powering is reliable even when dimming of the load is contemplated.

(48) FIG. 8 illustrates the situation where a direct connection to neutral is available. In this instance a commercially available high voltage power supply 400 is supplied from active 401 and neutral 402 and makes DC power 403 available to microprocessor 404 and any other components within the switch assembly 410 which may require it. Because, in this instance, the high voltage power supply 400 receives its active and neutral connections directly it is not influenced by whether relay 405 (controlling active power to load 406) is in an open or closed condition.

(49) With reference to FIG. 9 there is illustrated diagrammatically the situation where there is no direct neutral connection available for the high voltage power supply 400. An indirect connection 407 is available which will provide a voltage difference as between active connection 401 and indirect neutral connection 407 when relay 405 is in an open condition. This voltage difference can be used to power the high voltage power supply 400. However, as illustrated in FIG. 10, if the relay 405 is closed (or if there are a number of relays all are closed) then there is no voltage drop as between active connection 401 and indirect neutral connection 407 and hence, in this situation, there is no power available to power the high voltage power supply 400.

(50) In one embodiment as illustrated in FIG. 11 the solution is to include a low voltage power supply 408 in series in the active connection 401 to load 406. This low voltage power supply comprises an internal load which in a preferred form can be adjusted depending on the current draw of load 406 to provide a stable voltage drop across it when relay 405 is closed sufficient to power microprocessor 404 and any other electronic load required within the switching assembly 410. When relay 405 is open power is again supplied to the high voltage power supply 400 by the voltage drop across the relay 405 itself as was the situation described with reference to FIG. 9. Broadly then local DC power is always available either via a voltage drop across relay 405 or via a voltage drop across the low voltage power supply 408.

IN USE/INDUSTRIAL APPLICABILITY

(51) The switch assembly of the present invention provides an aesthetically attractive switching system which has no toggle switches or rotatable knobs susceptible to wear or damage. The combination of both switching and optional dimming functions within the relatively small space required by the sensors of the invention, allows the control of a relatively large number of light sources from a compact wall plate, or through RF receiver/transmitter technology.

(52) When equipped with RF receiver and transmitter modules, different switch assemblies in a building may be programmed to communicate with each other so that an activation or de-activation input at one switch assembly may be acted upon by other switches programmed to respond. Thus for example, one switch assembly suitably located may be programmed to communicate with all, or a selected number of light source switch assemblies in the building to either switch on or switch off the relevant light sources.

(53) The same communication facility may be employed with suitable programming to disable/enable all, or a selection of power outlet sockets in a building.

(54) Another advantage of the switching system of the invention is that, as shown in FIG. 5 more than two, indeed an almost unlimited number of switch assemblies may be arranged as an intermediate switching array to operated the same light source or light sources connected to just one of the switch assemblies in the array.

(55) It will be understood that the switch assemblies of the invention when equipped with RF transmitting modules, need not be hard wired to the light source or other electrical device which a switch of the switch assembly controls. Connection to the remote light source or electrical device may be effected wirelessly by an RF receiver connected to or incorporated in the light source or electrical device.

(56) The simple locking and unlocking facility of power outlets afforded by the arrangement of the present invention as described in the Second Preferred Embodiment above, clearly provides a convenient and important safety measure against accidental electrocution should a child insert a conducting object into a power socket.

(57) As well as being easily cleaned and aesthetically pleasing, the switch system of the present invention can be more readily operated by people not having full dexterous use of the hands.

(58) The fact that the relays and other components are solid state eliminates the possibility of arcing. As a bonus, the illumination of the sensor positions within the front face plate is particularly convenient at night.

(59) The above describes only some embodiments of the present invention and modifications, obvious to those skilled in the art, can be made thereto without departing from the scope of the present invention.