FR2774497A1 - Remote control method for electrical appliances - Google Patents

Abstract

The system uses several capacitive sensors enabling control from a number of points. The method for remotely controlling at least one electrical appliance (4) uses at least one and preferably several control sensors (5). A control (7) is mounted in the power supply line (8) between the appliance and the mains. Connecting cables (6) are provided linking the sensors to the control. The sensors may comprise capacitors of predetermined characteristics, which can be influenced by the presence or contact with the user. The detection uses an exclusive-OR gate operating on a square signal produced by a clock circuit, and a signal transformed by passage through an LCR circuit whose capacitance varies according the control sensor capacitor.

Description

The present invention is in the field of

distance

of electrical appliances.

  Devices for remote control of electrical appliances are already known.

  In addition to conventional switches having two son in which passes the supply current of the device to be controlled, control devices using leakage currents are known. There are known in this field processes for lowering the resistivity of non-conductive products by chemical treatment. The use of such a method makes it possible to control the ignition of a lamp, for example, by simple contact with the foot of the lamp. Other powerline and wire devices are also documented. However, limits exist for these various devices. In particular, they either present the danger of circulating large currents and therefore potentially dangerous near the user, or they have a limited scope of control. Furthermore, remote control systems using leakage current signal analysis involve the presence of a protective resistor to avoid any danger to the user. The present invention therefore intends to overcome these disadvantages by proposing a new device for remote control of electrical appliances. According to another purpose

  important of the invention, the device is safe for the user.

  According to a third object of the invention, the device is simple and economical to manufacture. Finally, according to another object of the invention, the device simply adapts to

  existing appliances and installations.

  The object of the present invention is therefore a method of remote control of at least one electrical appliance, using a device comprising at least one control sensor, a control unit to which the power cables of the electrical appliances are connected. to control at least one conductor connecting the sensor to the control unit, characterized in that - the sensor has a capacitance effect of predetermined characteristics, - the control detection is carried out using an electronic band pass filter and the analysis of the electrical signal of the circuit composed of the wires and sensors, as

  the user is in contact with a sensor or not.

  It will be understood that, thanks to this arrangement, the use of a power supply switch device, which involves the circulation of electrical power potentially very dangerous for the user, by a control method based on the frequency analysis, is replaced. of the signal and can therefore use sensors without circulation of

  dangerous electrical power, and without moving mechanical parts.

  The description which follows, made with reference to the attached drawings for a purpose

  explanatory and in no way limitative, allows a better understanding of the benefits, goals and

features of the invention.

  Figure 1 shows a conventional electrical device control assembly.

  Figure 2 shows the different main components of the device

  Figure 3 is an electrical diagram for detecting phase variation.

  Figure 4 illustrates in more detail the circuit diagram of the device.

  Figure 5 illustrates a typical installation.

  Figure 6 shows the different electrical signals as a function of time, in

  the case of sensor in air (Figure 5A) or human contact on this sensor (Figure 5B).

  Figure 7 gives the algorithm for monitoring the resonance frequency of the electrical circuit. Figure 8 shows the correspondence between the measured voltage for a length

  of wire chosen as an example of 10 m, and the frequency of the clock.

  Fig. 9 illustrates a variant using an overvoltage variation detection method. As can be seen in FIG. 1, a traditional control of electrical appliances comprises one or more switches 1 connected to the low-voltage network 2, and connected by a conductor 3 to an apparatus to be controlled, here a lamp 4. The low current voltage flows in all switches, which is a source of danger for the user. In the case of a device according to the invention illustrated in FIG. 2, the device is composed of several main elements which are one or more tactile sensors 5, a conductive link 6 and an electronic unit 7 acting as the central data analysis unit. of the sensor and transmitted by the conductive connection 6. The touch of a touch sensor 5 creates a voltage variation in the conductive line 6. This signal is interpreted by the electronic unit 7 which controls by a link 8 the operation of

  the electrical apparatus 4 by generating several functions: on, off, variation.

  l / touch sensor Unlike other touch systems that use metal sensors, the present device can also use sensors of insulating materials (plastic,

  ceramic, wood) surface-treated with a product that lowers resistivity.

  In a preferred embodiment, a touch sensor 5 of the present device is made in the form of a surface delimited by a square of 8 cm side (similar to the dimensions of conventional switches). The surface can present a sculpture

  omnementale, and has no moving part.

  The touch sensor 5 is made in several stages of shaping, processing and

  possibly surface protection.

  The touch sensor 5 is made for example ceramic traditional white earthenware enamelled on one side. The realization is done by classical techniques

known to those skilled in the art.

  The surface treatment is intended to produce a capacitor effect by making the surface of an insulating material conductive. This effect, which creates the tactile function of the sensor, is obtained by spraying a carbon-based conductive lacquer (or

  nickel), then drying at room temperature.

  2 / Conductive bond The conductive bond is, in the embodiment shown, made in the form of a silver-plated copper wire with a diameter of 0.127 mm and a nominal resistance of 155 Ω / 100 m coated with "Teflon" trademark (PolyTetraFluorEthylene), with a total diameter included

  between 0.38 and 0.48 mm. This wire is installed in a classic way.

  3 / Electronic control entity The principle of the electronic control unit 7 is based on the use of a

  bandpass filter, using a frequency providing maximum detection sensitivity.

  The support on the touch sensor 5 by a user will add to the circuit a capacity

image of the user.

  This support therefore causes a change in the frequency that results in two phenomena: - a phase variation between a clock and the signal, - a drop in the voltage, whose amplitude is a function of the sensitivity that one

wants to get when supporting.

  The control device, in the preferred embodiment described here,

  detects the phase variation, for a better sensitivity reason.

  Positioning at a point approximately mid-slope of the voltage versus frequency curve (FIG. 8) gives a sensitivity, characterized by the measured voltage difference according to the contact between the sensor and the sensor. the user or

no of the order of 30%.

  It is clear that the signal processing will be all the easier as this measured voltage difference will be large, and a variation of at least 5% seems necessary for a simple and reliable electronics to be suitable. This conditions the choice of the working frequency. It is quite clear, however, that the choice of another frequency does not modify the general principle of operation of the device As shown in a disposition currently envisaged in FIG. 3, the electric diagram of the system, of RLC form, comprises first of all a variable clock 9 of

  a type known to those skilled in the art, centered on a frequency F of, for example, 250 kHz.

  The clock provides 0-5V square signals. This clock 9 is connected to a resistor 10 followed by an inductor 11 of 1 or 2mh, and three parallel-mounted capacitors 12 of 330 pf, 13 which represents the wires, and 14 of the sensor, of 40 pf. Yarns 6 have a capacity 13 which naturally depends on their length and their nature, but which can be here about

pf / m.

  The resonant frequency of the device is calculated by the formula f0 (Hz) = 1 / 27i Rac (1 / LC) and we obtain as an example approximately 150 kHz for a capacitance (equivalent

  total) C of 1000 pf and an inductance of 1 mh, in an application with 6 meters of wire.

  In the case where the length of the son 6 exceeds a few meters, it is possible to reduce the value of the capacity 12, because this reduction will be compensated by

  the increase in capacity related to the increased length of the wires.

  In the diagram illustrated in FIG. 3 of a phase variation detection solution, the assembly described above is followed by a resistor 15 with a value IM, a circuit 16, 17 for limiting the signal voltage, and an "exclusive-OR" comparator 18 o is injected with a signal coming from the clock 9. The signal coming out of this comparator goes into a resistor 19 of 10 kΩ A RC quadrupole (the capacitor 21 typically having a value of 10 nf) of time constant = RC sufficiently high compared to the period of the input signal outputs the mean value of the input signal without its

variable component.

  FIG. 4 shows the elements of the electrical control diagram, as described and illustrated in FIG. 3, integrated in a complete circuit diagram for controlling a lamp 4. In this diagram, the electrical wires in which circulates the low voltage network current are shown in thicker lines. The mains source 2, the supply wires 22, 23 of the electrical apparatus 4 to be controlled (a lamp in this case), the current-interruption device 24 mounted on the trigger of a triac 29 are recognized, controlled by an integrated circuit 25, for example of microcontroller or other type, which comprises the clock 9. The circuit 25 is powered by a transformer 26 protected by a fuse 27. A quartz 28 provides the time source for mounting . The "exclusive-OR" comparator 18 is made of several components in a conventional manner, and the assembly of the power supply of the circuit and of the time source 28 are known.

  the man of the art and are therefore not detailed here.

  The general diagram of a typical installation is shown in FIG. 5. The electronic control unit 7 is integrated in a housing 30 of the type adapted to be mounted on a conventional electric panel rail 31. To this box are connected upstream the network 2, protected by a circuit breaker or circuit breaker 32 of known type, of power adapted to the type of electrical device 4 to be controlled. The phase, neutral and earth poles are then connected to the poles 33 of the housing. This housing is in the presented version connected by a series of connection points 34 to three lamps 4A, 4B, 4C, two of which 4A, 4B are controlled together. The connection son 8, 22, 23 to the low voltage network and to the lamps are of known type, and for example of the "HO7VU" type of 1.5 mm2 section. At the same housing 30 are connected on lugs 37 of the touch sensors 5A, 5B, 5C (three in the example shown), here two of 5A, 5B are connected to one and the same junction box 35 and control the lamp 4C. Witnesses 36 of operation of electrical appliances

  controlled are integrated in the housing 30.

  The operating mode of the device is simple, the connection of the devices having already been described, the use of touch sensors 5 is natural for the user, a contact on the area of the touch sensor 5 causing the start or stop of

the apparatus 4 controlled.

  The operating principle is illustrated in FIG. 6 in which the left part illustrates the situation for the touch sensor 5 in the air (without human contact), and the right part shows the situation of the signals for the touch sensor 5 in contact with the sensor. 'an user. As can be seen, the clock 9 provides an identical signal in both cases, of square form 0-5V. The voltage at the dividing point between the three capacitors 12, 13, 14 is

  in the case of sensor 5 in the air a sinusoidal signal 0-30V.

  As mentioned above, when the hand is touched on a touch sensor 5, the image capacity of the user is added to the circuit and the proper pulse of said circuit changes, thus causing a phase variation between the clock 9 and the signal, this signal has a maximum voltage reduction AV, the maximum voltage being reduced to 5V

about, with a phase shift A (p.

  At the input of Trigger 16 (two-level trigger device), the signal is time-shifted. At the output of Trigger 16 there is a rectangular signal offset from the signal observed in the absence of contact of the user. Therefore, at the output of comparator "Exclusive OR" 18, the signal has a series of stalls and a

  continuous component A weaker in the case shown.

  With regard to the method for initializing the resonant frequency, it

  uses a software procedure, the code of which is appended to this description (software

  monitoring the resonance frequency of the electrical circuit).

  On the principle of the algorithm illustrated in FIG. 7, from the experimental frequency f0, an algorithm for tracking the minimum value of the signal of

  control measured by a microcontroller.

  More precisely, and as summarized by the sensor sensitivity adjustment algorithm and the illustration of FIG. 8 which shows the correspondence between the frequency sent by the microcontroller and the voltage recovered at the output of the bandpass filter, When we have reached 40 KHz, we reset the frequency to the value that was recorded together with the threshold (this is the resonance frequency), and to obtain a better sensitivity, we divide the maximum threshold saved (SeuilM ) by 2 (ThresholdM

  represents point 38 of the figure).

  Starting from the resonant frequency, the frequency generated by the microcontroller is re-incremented until a voltage equal to or near the output of the filter is obtained at the output of the filter.

  new threshold (ThresholdM / 2 in our case, ie at point 39 in the figure).

  From this moment, the system becomes operational and takes into account the user's touch on the circuit sensors. As can be seen, in this point 39, the difference in voltage between the tactile sensor situation in the air (curve 40) and the contact sensor situation (curve 41) is maximum, which is favorable to a sensitivity

maximum of the control device.

  The curve 40 relates to the released sensors and the curve 41 relates to the sensors

affected, that is to say in contact.

  The markers, squares for 40 and circles for 41, schematize the laches and affected.

  The curve is in the space [1 178 Khz; 218 Khz] in the case of a connection of meters. If we extend the link, the space will tend towards the lower frequencies and vice versa, if we shorten the link, the space will tend towards the frequencies more

high.

  As we have seen, the advantages of the device are - the reduction of the distance constraint between the sensor 5 and the electronic control unit 7 with for example a possible distance of a few tens of meters with metal sensors, - the absence of parasitic triggering if the wire 6 is shielded, - the possibility of controlling the sensitivity, - the total decoupling between the sector 2 and the sensors 5, by the use of a transformer 26 lowering the voltage to create the + 5V supply, - the suppression of a 220 V "dragging" on the circuit, which can be particularly interesting, for example for electric control in bathrooms,

  or in a risky or flagrant environment.

  It is also obvious that the use of sensors 5 treated insulating materials and low currents (of the order of a few micro amperes) necessary for the operation of the device significantly improve safety by reducing the risk of electrocution. The links 6 and the sensors 5 used significantly reduce the

  risks of short circuit of the installation.

  In an alternative surface treatment of the sensors 5, an electrolytic solution treatment is used. Ion solution treatment to make the sensor 5 conductive at the surface to create the tactile effect, uses a chloride solution

ferric FeCl3 or derivative.

  a / The first phase is a pretreatment of the ceramics by passing in an oven at 100 C for 24 hours to desorb moisture and other surface contamination products. Cooling is carried out at room temperature

  in desiccator to prevent any moisture recovery.

  b / The treatment bath comprises a ferric chloride solution with a concentration of 740 g / l at 20 ° C. The bath temperature is between 18 and C (preferably 25 ° C.) and is thermostatically adjusted. This temperature determines the amount of conductive solution absorbed by the ceramic and consequently the impedance of the resulting sensor. Temperature also affects

  the diffusion depth of the solution in the ceramic.

  c / The impregnation of ceramics is done by placing the ceramics in the bath. Only the unglazed side is in contact with the ferric solution. The immersion level is of the order of half the thickness of the ceramic. The

  immersion time is between 20 and 180 minutes.

  d / The drying of ceramics comprises first a drainage of ceramics for one hour at room temperature, then a passage in a stainless steel oven ventilated at 40 C for 24 hours. The cooling of ceramics is

  at room temperature in desiccator.

  e / The treated surface is finally isolated by spraying a silicone type varnish tropicalization based polymnthylphenylsiloxane resin (for example known under the trade name Rhodosil 99 1), and polymerization of the silicone film covering the treated side at a temperature of 70 at 80 C for 2 hours. An alternative ionic solution treatment of earthenware sensor 5 uses ferric chloride instead of copper sulfate or calcium dihydroxide. In the case

  sandstone sensor, aluminum alum is used in another variant.

  In an alternative embodiment of the sensors 5, the traditional white glazed ceramic type ceramic, on one side, which has a porosity of 10 to 15%, is

  replaced by sandstone with a porosity of 0.5 to 3%.

  In another variant embodiment of the ceramic sensors, another barrier material (replacing the tropicalization silicone varnish) may be added, by

  example by depositing PTFE ("Teflon") aerosol on the treated side of the ceramic.

  In yet another embodiment of sensor 5, these are made of plastic material, and treated by electroplating a conductive metal layer. In an embodiment of conductive connection 6, the sheathed wire is replaced by a chemical conductive bond of the aluminosilicum powder type.

  impregnated with ferric chloride on a PVC support (electric duct).

  In a variant of a human contact detection method, illustrated in FIG. 9, the detection principle is no longer based on the analysis of a very low frequency signal but on the detection of variation of voltage, according to a detail of implementation. artwork

known to those skilled in the art.

  It is also clear that one can choose another centering frequency of the bandpass filter than that having a maximum sensitivity selected in the preferred embodiment. For example, it is possible to center the filter on the resonant frequency of the device, with maximum gain and minimum sensitivity. Frequency choice higher than the resonance frequency is also possible, with performances in

  sensitivity reduced compared to the invention.

  In another non-preferred production approach because more expensive has been achieved, each

  sensor 5 comprises a quartz crystal device (or piezoelectric characteristic material).

  similar electrical ones) such that any mechanical deformation of the crystal causes the appearance of electric charges on its surface. It is then sufficient to detect these charges to know if the sensor is touched or not. In this case, the command detection is no longer performed using an electronic bandpass filter, but it always includes a

  signal analysis part similar to that described for the present frequency system.

  The scope of the present invention is not limited to the embodiments presented but rather extends to improvements and modifications to the scope of the invention.

the skilled person.

  * CalagRLC: Resonance Frequency Adjustment Procedure * This function adjusts the resonance frequency of a * RLC circuit. This RLC circuit takes into account the impedance of the link At * * <- Umax and f resonance * * * <-U adjustment * * *

* **** *************************

  * fmin finax * ** Internal variables (with function) ** DTP, SedilM CalagRLC Idi armc, 0000lOOb; fimax = 400KHz Idi arrc, OEBh Idi arcp, OF5h Idi armc, 1 100000l b

TEMPORLC

  Idi a, 20; tempo frequency applied TEMPO50u dec a jrnz TEMPO50u ACQIV Idi wdr, watch; acquisition input sensor set O, ora Idi adcr, Ol Oh nop nop Idi adcr, 030h

ACQIVI

  jrr 6, adcr, ACQIVI Id a, adr clr adcr cp aSeuilM; sensor value> ThresholdM jmrnc ACQIV_3; yes => sensor value = ThresholdM jp ACQIV_7; no => nothing is done

ACQ 1 V3

  Idi arrnc, 020h Id ThresholdM, a Id a, arrc Id arrcM, a Id a, arcp Id arcpM, a

ACQ1V_7

  dec stop O, arrc, ACQ I V_2; management cyclic report of arcp

ACQIV_2

  Id a, arrc; continue the range scan jrz ACQ1V_4 Idi armc, I 100000b jp TEMPORLC ACQIV4 Id a, ThresholdM; This is the result of the above-mentioned method, which is one of the following: Restores resonance frequency Id arrc, a Id a, arepM Id arcp, a Idi armc, 11100000b

TEMPRLC

  Idi a, 20; tempo frequency applied TEMP50u dec a jrnz TEMP50u OCQIV Idi wdr, watch; acquisition input sensor set 0, ora Idi adcr, 0 1 Oh nop nop Idi adcr, 030h OCQIVl jrr 6, adcr, OCQ I V 1 Id a, adr clr adcr cp a, SeuilM; sensor value <ThresholdM / 2 jrc OCQIV_3 jp OCQIV_7

OCQIV _3

jp FINAJCAP

OCQIV 7

  Idi armc, 020h; increases the frequency inc arrc jrr 0, arrc, OCQ 1V_2 inc arcp

OCQIV 2

Idi armnnc, 1 1 1 00000b jp TEMPRLC

FINAJCAP

  Idi armc, 020h; decreases the frequency of the unit, dec arrows 0, arrc, OCQl V_9 decipp OCQIV 9 a Idi armc, 1 1 00000b ret EJECT

Claims (4)

CLAIMS:   1. A method of remote control of at least one electrical device 4 using a device comprising at least one control sensor 5, a control unit 7 to which are connected the power supply cables 8 of the electrical devices 4 to be controlled, to at least one conductor 6 connecting the sensor 5 to the control unit 7, characterized in that: the sensor 5 has a capacitive effect of predetermined characteristics; - Control detection is performed. by using an electronic pass-band filter and analyzing the electrical signal of the circuit according to whether the user is in contact with the sensor 5 or not.   2. Device for remote control of at least one electrical apparatus for carrying out the method according to claim 1, characterized in that the control detection is performed using the method according to claim I. Device for controlling an electrical apparatus 4 for a device according to claim 2, characterized in that the control detection is based on the use of an "exclusive-OR" comparator between a square signal derived from a clock 9 and a signal transformed by passing through an RLC circuit whose capacity varies according to whether   user touch or not touch sensor 5.   4. Conductor 6 intended to provide the connection between a touch sensor 5 and a control unit 7 for a device according to claim 2, characterized in that it is made of silver-plated copper of diameter 0.127 mm, sheathed with PTFE and a total diameter included between 0.38 and 0.48 mm.