FR2756684A1 - TOUCH CONTROL DEVICE, ELECTRICAL EQUIPMENT AND INSTALLATIONS PROVIDED WITH THIS DEVICE, AND ASSOCIATED EMBODIMENT PROCESS - Google Patents

Abstract

The invention concerns a device (10) for tactile control of an electrical equipment (2), from a single phase source of alternate voltage (V), comprising: a bi-directional controlled switch, arranged in series with said voltage source and said electric equipment (2); a circuit for controlling this bi-directional switch,; and means for detecting a tactile control, comprising a circuit for processing the leakage current signal picked up on an electrically conductive zone of the electrical equipment.

Description

"TOUCH CONTROL DEVICE, EQUIPMENT AND
ELECTRICAL INSTALLATIONS PROVIDED WITH THIS DEVICE, AND
ASSOCIATED REALZSATION PROCESS
The present invention relates to a touch control device. It also relates to electrical equipment and installations provided with this device, as well as an associated production method.

 The adjustment of the light intensity of lighting equipment by touch control devices is now widely known, as illustrated for example by document GB-A-2 249 378. In most of the equipment proposed, the area of touch control is limited in area, for example a conductive patch, the base of a bedside lamp or the metal structure of a lampshade. Also known from document FR-A-2 701 792 are luminaires in which the tactile contact zone consists of all or part of the external surface of the support of these luminaires, this support being previously subjected to an impregnation treatment in order to make it conductive.

 Most touch-sensitive light equipment also have in common the use of a triac, a widely used electronic component of power, for applying a form d to a resistive and / or inductive load, in particular a bulb or a tube. voltage wave corresponding to an adjustable fraction of the half-arches of the sine waveform of the mains voltage. This triac is controlled by an electronic circuit directly connected to the mains and designed around a specialized integrated triac control circuit, such as the SLB 0587 circuit from SIEMENS.

 This specialized circuit provides a triac control particularly suitable for the adjustment of lighting equipment. It is widely used in an electronic circuit structure recommended by the manufacturer. This circuit is in fact typically suitable for applications in which the sensitive or contact zone is located only a few centimeters from the circuit itself, for example for a sensitive wall switch. These are applications which can be designated under the term of direct sensitive contact.

Most of the current touch-controlled electrical equipment has small touch zones which are generally metallic. These limitations most often imposed by problems of reliability of the control can constitute for the user of these equipments a constraint and an operational embarrassment contributing to slow down the development of this type of equipment with tactile control. The document
FR2701792 certainly discloses equipment with tactile control in which the tactile zones can extend over a large part of the external surface of a support made of insulating material, but this support must first be treated to reduce the electrical impedance of one of its zones so that the reduced impedance zone is electrically isolated, that it is brought into electrical contact with a detection input of a control circuit and that it has a portion accessible to the touch, so as to allow the appearance of leakage currents when this portion is touched by an operator. This treatment is carried out in practice by impregnating the area concerned with an ionic solution such as an aqueous solution based on iron perchloride. This presupposes in practice that the material constituting the support to be treated is relatively porous to allow this impregnation.

Furthermore, it seems difficult to control the level of penetration of the ionic solution within the treated area and to be able to guarantee stability over time of the electrical characteristics of the treated areas.

 The object of the present invention is to remedy these drawbacks by proposing a tactile control device which is suitable for the use of large or remote tactile zones, while not requiring prior impregnation of the insulating supports.

This is obtained with a device for controlling in touch mode the supply of electrical equipment, in particular lighting equipment, from a single-phase alternating voltage source, comprising:
- bidirectional switch means controlled to generate adjustable fractions of half-cycles of supply voltage from the single-phase alternating voltage source,
means for phase-controlling said two-way switch means, in particular on the basis of the detection of a leakage current between a tactile zone and a neutral reference associated with said single-phase alternating voltage source, generated when a user puts in contact a part of his body with said tactile zone, and
- Means for detecting this leakage current connected to the phase control means.

 According to the invention, the means for detecting leakage current are connected to an electrically conductive area disposed near the tactile area and separated from the latter by at least one area made of insulating material.

 In the tactile control device according to the invention, the electrically conductive and tactile zones respectively are clearly distinct, unlike in particular the control devices disclosed in FR2701792 in which the physical impregnation mechanism contributes to creating, from the interior surface towards the surface accessible to the touch, an intermediate zone with a negative electrical conductivity gradient. With the present invention, an insulating zone is purposely maintained between the tactile zone and the conductive zone, with the technical effect of guaranteeing a high level of security for the users with regard to any risk of electric shock while providing high sensitivity. in detecting leakage currents.

 In a preferred embodiment of a device according to the invention, the electrically conductive area is produced by an electrically conductive coating deposited on an inner face of a support piece of insulating material, the outer face of which includes the tactile area. This electrically conductive coating consists, for example, of a thin layer of an electrically conductive material. This type of coating can be produced using multiple deposition techniques. A particularly simple and economical deposition technique consists in depositing one or more layers of a binder comprising conductive particles.

 Furthermore, it has been noted by the present applicant that the application of the circuit recommended by the manufacturer of the SLB 0587 circuit to luminaires provided with tactile zones remote from the phase control circuit could lead in certain situations and configurations to problems of reliability and lack of performance due to the fact that the sensitive zone can be more than a meter from the circuit and that the contact is transmitted by the structure of the device and not by an electric wire. In addition, for luminaires comprising a large contact surface as is the case for the present invention, it has been found experimentally to be highly sensitive to radiated or conducted electromagnetic disturbances which may lead to nuisance tripping. In addition, the current electronic touch control circuits are sometimes sensitive to disturbances carried out on the sector.

 Advantageously, provision may be made for the leak detection means to further comprise means for processing said current current signal taken from the electrically conductive area so as to discriminate any signal induced on said conductive area by external disturbances.

 The leakage current detection means are also preferably arranged to provide leakage current detection when the leakage impedance (Zf) associated with the control contact is either of very high module, or of very low module.

 In a preferred embodiment of the invention, the touch control device further comprises means for processing the single-phase alternating voltage upstream of the phase control means so that said phase control means are substantially immune to any disturbance line coming from the single-phase alternating voltage source.

 When the touch control device according to the invention further comprises means for supplying the phase control means from the single-phase alternating voltage and means for regulating the supply voltage generated by these supply means, these means control are preferably oversized current compared to the nominal size recommended for said phase control means for operation in sensitive control.

 In the practical case of a touch control device according to the invention, the power supply means of which comprise at least one rectifier component and a capacitive component, it can advantageously be provided that this touch control device also comprises a resistive component arranged upstream of the phase control means between the phase line and the supply means for discharging said capacitive component.

 According to another aspect of the invention, there is provided electrical equipment comprising at least one operational member supplied from an alternative power source and a touch control device according to the invention, characterized in that it is further comprises a hollow support piece of insulating material comprising on its outer surface the tactile zone and on its internal surface the electrically conductive zone.

 The hollow support piece may for example be a cylinder or a tubular structure. The electrically conductive zone can be produced by depositing and drying a thin layer of an electrically conductive solution on the inner surface of the support piece. This electrically conductive solution can for example comprise carbon powder in suspension in a binder such as emulsion glue.

 The present invention can relate to any type of electrical equipment, in particular lighting equipment, street lamps, bedside lamps, but also motorization equipment.

 According to yet another aspect of the invention, an electrical installation is proposed comprising a set of electrical equipment powered by an alternative voltage source and a set of touch control devices according to the invention, characterized in that it comprises at least one support piece made of insulating material comprising on an external face at least one tactile zone and on an internal face an electrically conductive zone connected to leakage current detection means, this electrically conductive zone being isolated from any structure connected to the potential reference.

 The support piece can for example be produced in the form of a U-shaped profiled strip provided with a cover or cover plate and arranged along a wall.

 Another aspect of the invention relates to a method for producing a tactile control device according to the invention, characterized in that it comprises depositing an electrically conductive coating on the interior surface of a support piece of insulating material, the interior surface has a tactile zone.

When this process is applied to a hollow support piece of insulating material, this deposition is carried out by the following steps:
- filling the hollow support piece with an electrically conductive solution comprising electrically conductive particles suspended in a binder,
- evacuation of this solution from the hollow support part, and
- drying of the interior of the hollow support part.

 These deposition steps can of course be repeated as many times as necessary to obtain an appropriate thickness of conductive coating.

Other features and advantages of the invention will appear in the description below. In the appended drawings given by way of nonlimiting examples:
- Figure 1 illustrates schematically the
detection principle implemented in the
touch control device according to the invention;
- Figure 2 illustrates a first example of implementation
work of a touch control device according to
the invention for controlling equipment
lighting;
- Figure 3 illustrates a second example of implementation
work of a touch control device according to
the invention in the form of a profiled rod;
and
- Figure 4 is a sectional view of a baguette
touch control profile implemented in
an electrical installation according to the invention.

 We will now describe the structure and essential functions of a touch control device according to the invention, together with an associated production method, with reference to the aforementioned figures.

In the following, we will designate by the same reference elements or components common to the three figures.

A touch control device 10 according to the invention is connected at the input to an alternating voltage source V and at the output to a load 22 within an electrical device 2, and is controlled by means of leakage current detection If generated by contact of a tactile zone 20 with a finger 32 of an operator 30 or another part of the body. The tactile zone 20 is constituted in practice by an external surface zone of a support piece 24 whose internal surface is covered with an electrically conductive coating 27 connected to the leakage current detection input of the tactile control device 10. The zone 28 located between the conductive coating 27 and the tactile zone 20 consists of an insulating material such as wood, glass, porcelain, earthenware or any other suitable material. The support piece 24 must imperatively be isolated from the neutral reference N of the alternating voltage source V, so that the impedance Zi between this support piece and this neutral
N is much greater than the leakage impedance Zf present between the tactile zone 20 and the neutral reference N in the touching situation. The tactile control device 10 is designed to be able to detect any significant variation in the leakage current If and to discriminate any parasitic signals picked up due to the extent of the tactile surfaces.

 Consider for example, with reference to FIG. 2, a lighting equipment 1 comprising a luminaire 2 comprising for example a base 21, a tubular structure 24, a module 26 for receiving an incandescent or halogen electric bulb 22, and a electronic dimmer incorporating a touch control device 10 according to the invention connected to the lighting equipment by a cable 23 or directly included within said lighting equipment.

 The tubular structure 24 is made of insulating material such as wood, ceramic or a plastic material. The external surface of this tubular structure accessible to the touch constitutes a tactile zone 20 which can moreover be coated with a paint or a varnish in one or more layers, while the internal surface comprises an electrically conductive coating 27. This conductive coating can for example be produced in the form of a layer of an electrically conductive material deposited. An electrical cable 29 for supplying the bulb 22 is passed inside the tubular structure.

 The touch zone 20 is necessarily isolated, for example by an insulating part 25, from the base 21 if the latter is conductive and from the surface 50 on which the luminaire 2 is placed. The electrical insulation can also be obtained with a segment of zone 28 not covered with the electrically conductive coating. The level of electrical insulation that the insulating part 25 must have depends directly on the electrical conductivity of the material constituting the tactile zone and on the dimensions of the latter.

 The touch control device 100 comprises a control part C and a power part P comprising a triac 15 acting as a controlled bidirectional switch and controlling the electrical supply of the bulb 22 from a single-phase alternating voltage source V which is generally the sector, via a transformer 14. A circuit FC for filtering the alternating input voltage is arranged upstream of the triac 15 to protect the touch control device 100 from any untimely control due to a disturbance on the sector.

 The control part C is built around a phase control circuit 100, in practice a specialized integrated circuit such as the SLB 0587 circuit from SIEMENS or an equivalent circuit, receiving a leakage current signal coming from the touch zone 20 through a discrimination circuit FR connected to the conductive area 27 and emitting a signal T for triac tripping 15.

The leakage current signal is previously processed by the discrimination circuit FR. It is then subjected, within the SLB 0587 circuit, to an input control, then to a signal evaluation and recognition, and applied to the input of a PLL phase lock loop (Phase Loop Lock). This phase locked loop is coupled to a synchronization module connected via an input 4 to the power part P to take an image of the voltage across the triac 15, and is connected to an external integrator circuit RC via pins 3 and 7 of the integrated circuit 100. The phase-locked loop synchronizes the triac 15 trigger pulses with the AC voltage signal, and supplies clock signals to a safety blocking module, to a control unit. timer, evaluation and recognition module, a counter for storing the lighting setpoint and a comparator module. The phase control circuit 100 further comprises a trigger pulse output logic and an output stage delivering at output 8 the trigger pulses T, and is provided with a circuit for supplying from the mains voltage a supply voltage rectified at input 7 with respect to a ground reference 1.

 The discrimination circuit FR is here produced in the form of two capacitors Csl, Cs2 (1 nF, 2 kV) in series with the paralleling of a resistor Rp (4.7 MQ) and a capacitor Cp (10 nF). The resistor 12 disposed between the phase line Ph and the detection input 5 is preferably determined as a function of each type of luminaire controlled. As a practical example, the resistance 12 is chosen from a range of 100 kQ to 800 kQ, therefore at values significantly lower than the values recommended by the manufacturer, namely from 1 MQ to 4.7 MQ. The use of a resistor 12 of lower value made it possible to obtain a satisfactory detection sensitivity in control situations where the tactile zone is of large dimension, the values recommended by the manufacturer being in fact adapted to uses of control by sensitive button.

 The presence of the capacitor Cp in parallel on the resistor Rp has the effect of increasing the intensity of the leakage current while not affecting its active component. This classic effect due to the capacitive phase shift provided by the capacitor is used here to obtain greater sensitivity of the touch control device according to the invention. Furthermore, the capacitors Csl, Cs2 connected in series contribute to reinforcing the safety of the user.

The supply circuit VS adopted in the touch control device according to the invention differs from that recommended by the manufacturer in that one of the filtering capacitors 16 is chosen at a value (68 pF) significantly lower than those recommended by the manufacturer, namely between 10 and 100 nF. This choice made it possible to considerably strengthen the immunity of the phase control circuit to HF disturbances conducted on the sector by eliminating numerous untimely control situations. It should also be noted that it is necessary to provide a Zener diode 17 for regulating the supply voltage of the phase control circuit which is oversized in current compared to the manufacturer's recommendations for operation in sensitive control, in order to guarantee satisfactory operation of the touch control device 10 according to the invention. As a practical example, a reference Zener diode has been used here.
BZX85C.

 Furthermore, in certain specific applications of the touch control device according to the invention, it may be advantageous to place a resistor 18 between the phase line and the anode of the Zener diode 17, in order to further increase the detection sensitivity. without deteriorating the reliability of the device. This resistor 18, which can for example be chosen to be equal to 680 kQ, has in particular the effect of discharging the capacitor 19 from the supply circuit VS and therefore of avoiding a voltage drift across the terminals of this capacitor.

 In addition to the HF 13 filtering circuit recommended by the manufacturer, there is provided upstream of the phase control circuit 100 an FC circuit for processing the input voltage which can be embodied in its simplest embodiment by a varistor which has a very high resistance as long as the voltage across its terminals remains below a threshold voltage, this resistance collapsing beyond this threshold voltage.

 We will now describe the operation of the touch control device according to the invention.

 When a user 30 puts one or more of his fingers 32, or another part of his body, in contact at any point in the tactile zone 20 of the luminaire 2, a leakage current then flows between the phase of the sector and the neutral N through the discrimination circuit FR, the conductive area 27, the material 28 constituting the tactile area 20, the finger (s) 32, the user's hand and body 30, and the ground. The various conductive components external to the tactile control device 10 can be modeled by a leakage impedance Zf, the module of which varies considerably depending on the location where the luminaire 2 is placed, in particular the wet or dry nature of the ground, the type of shoes. worn by the user and other environmental factors.

 The leakage current If is then detected and processed by the phase control circuit, for example the circuit SLB 0587, which generates triac tripping pulses T 15 by adjusting the angle or the tripping phase as a function of the duration of the contact 32 exerted on the tactile zone 20.

The phase control circuits, for example, the SLB 0587 circuit, are generally designed to memorize the extinction level and restore it on ignition if a pin (2) is left free. When this pin is brought to a high level, the lighting is then carried out at the maximum level, corresponding to a phase angle on ignition of 1520. The touch zone is connected to the input pin 5 of the SLB 0587 circuit. through the discrimination circuit FR and one or more resistors of several MQs which have the function of protecting the user. Furthermore, other protection components are provided within the touch control device according to the invention, such as a diode
Clipping zener.

 The passage from ignition to extinction and from extinction to ignition is effected by a short touch, of duration between 50 and 400 milliseconds.

The light intensity is adjusted by touching it for more than 400 milliseconds. The variation of the phase angle, and therefore of the illumination, is quasi-linear as a function of time until maximum illumination. The return to a minimum illumination is obtained by respecting a contactless period of time and then by exercising sufficient level contact.

 The implementation of the tactile control device according to the invention has made it possible in practice to operate reliably in a voltage range of 130 to 270 Volts, for conditions of use ranging from a state of high insulation (user on a base in plastic material at least ten centimeters thick) in a state of high conduction (wet ground).

 The present invention can advantageously be applied for the tactile control of luminaires such as floor lamps, table lamps, wall lights, etc.

 Furthermore, the present invention can be applied to the production of electrical installations provided with tactile control rods arranged on the walls of a room, as illustrated in FIGS. 3 and 4.

A shaped strip U-shaped 4 is for example embedded in a wall 41 so as to be substantially flush with the surface of this wall. This profiled rod, made of a plastic material, comprises an internal U-shaped part 44 and a cover or cover plate 49 also made of plastic material and designed to be clipped into the internal part 44. The cover plate 49 comprises on its inner face an electrically conductive coating 47, while its outer face constitutes the tactile zone 40, the plastic material constituting the plate performing the function of insulating zone 48. It is important to note that the electrical coating 47 must not cover the face internal of the cover plate 49 only partially, uncoated strips 46a, 46b having to be provided to guarantee sufficient electrical insulation between the conductive coating 47 and the body 410 of the wall 41 which is in practice at a potential substantially close to the system potential reference. These uncoated strips can in practice have a width of a few millimeters, for example 4 to 5 mm. The U-shaped arrangement of the profiled strip 4 further ensures that the electrically conductive area 47 is kept at a sufficient distance from the body 410 of the wall. In practice, a space 45 of approximately 1 mm is sufficient to guarantee this electrical insulation. Advantageously, provision may be made for such rods to be juxtaposed during the mounting of an installation and electrically connected by means of electrical connection pieces fixed respectively to the internal faces of the two corresponding cover plates at a junction 43 between two rods, to ensure electrical continuity of the conductive coatings. Known techniques for clipping can be used for this, in particular by using parts made of flexible contact material with low resistance. The internal faces 40 of the rods are then electrically connected to the leakage current detection input of a touch control device 10 according to the invention controlling the electrical supply of a load 42
After mounting and clipping the closure plates, the touch control strip can be covered with wallpaper, wall covering or one or more layers of paint or varnish. It is also possible to provide tactile control rods fixed to a wall without embedding, and many other arrangements, the internal structure of the rod guaranteeing perfect electrical insulation of the electrically conductive area with respect to ground.

 This particular embodiment can advantageously be implemented for remote control of electrical equipment.

 We will now describe, by way of nonlimiting example, a particular embodiment of a detection support part used in electrical equipment according to the invention such as a halogen lamp post comprising a tubular wooden structure.

 This tubular structure is previously filled with a conductive binder such as emulsion glue comprising conductive particles in suspension. One can for example use carbon black or graphite premixed in glue. By way of nonlimiting example of implementing the method according to the invention, a conductive binder can be produced in the following approximate proportions: for 0.7 liters of water, approximately 25 grams of graphite and 14 grams of glue.

 The tubular structure is then emptied, and a thin film of conductive binder, of thickness less than one millimeter, remains deposited on the interior surface of the tubular structure. Then drying, natural or forced, of this film. It has been found experimentally that a single deposition operation is sufficient to guarantee satisfactory operation of the touch control device. It may however be envisaged, in particular cases, to repeat the deposition operation one or more times in order to guarantee a homogeneous conductive coating over the entire useful surface of

Claims (23)

 1. Device (10) for controlling in touch mode the supply of electrical equipment (2), in particular lighting equipment, from a single-phase alternating voltage source (V), comprising:  - controlled bidirectional switch means (15) for generating adjustable fractions of half-cycles of supply voltage from the single-phase alternating voltage source (V),  - Means (100) for phase control of said bidirectional switch means (15), in particular from a leakage current (If) between a tactile zone (20, 40) and a neutral reference (N) associated with said single-phase alternating voltage source (V), generated when a user puts a part (32, 30) of his body in contact with said tactile zone (20), and  - means for detecting this leakage current (If) connected to the phase control means (100),  characterized in that the leakage current detection means are connected to an electrically conductive area (27, 47) arranged near the touch area (20, 40) and separated from the latter by an area made of insulating material (28 , 48).  2. Device (10) according to claim 1, characterized in that the electrically conductive area (27) is produced by an electrically conductive coating deposited on an inner face of a support piece (24) of insulating material whose outer face constitutes the touch area (20).  3. Device (10) according to claim 2, characterized in that the electrically conductive coating is produced by a thin layer of an electrically conductive material.  4. Device (10) according to any one of the preceding claims, characterized in that the leak detection means further comprise means (FR) for processing said current current signal taken from the electrically conductive area (27) so as to discriminate any signal induced on said conductive area (20) by external disturbances.  5. A touch control device (10) according to claim 4, characterized in that the leakage current detection means are arranged to provide leakage current detection when the leakage impedance (Zf) associated with the control contact. is of very high module.  6. Tactile control device (10) according to one of claims 4 or 5, characterized in that the means (FR) of leakage current detection are further arranged to provide a detection of leakage current when the impedance leakage (Zf) associated with the control contact is of very low modulus.  7. Tactile control device (10) according to claim 6, characterized in that the means (FR) of leakage current detection are further arranged to increase the intensity of the leakage current (If).  8. Tactile control device (10) according to any one of the preceding claims, characterized in that it further comprises means (FC) for processing the single-phase alternating voltage (V) upstream of the phase control means ( 100) so that said phase control means (100) are substantially immune to any disturbance conducted from the single-phase alternating voltage source (V).  9. touch control device (10) according to any one of the preceding claims, further comprising means (VS) for supplying from the single-phase alternating voltage (V) the phase control means (100) and means (17) for regulating the supply voltage generated by said supply means (VS), characterized in that these regulation means are oversized in current with respect to the nominal dimensioning recommended for said phase control means for operation in sensitive control.  10. Tactile control device (10) according to claim 9, in which the supply means (VS) comprise at least one rectifier component and a capacitive component (19), characterized in that it further comprises a resistive component (18) disposed upstream of the phase control means between the phase line (Ph) and the supply means (VS) for discharging said capacitive component (19).  11. Electrical equipment (2) comprising at least one operational member (22) supplied from an alternative power source (V) and a touch control device (10) according to any one of the preceding claims, characterized in what it is further comprises a hollow support piece (24) of insulating material comprising on its outer surface the tactile zone (20) and on its inner surface the electrically conductive zone (27).  12. Electrical equipment (2) according to claim 11, characterized in that the electrically conductive area is produced by depositing and drying a thin layer of an electrically conductive solution.  13. Electrical equipment (2) according to claim 12, characterized in that the electrically conductive solution comprises carbon powder suspended in a binder.  14. Electrical equipment (2) according to claim 13, characterized in that the binder is an emulsion adhesive.  15. Lighting equipment (2) according to any one of claims 11 to 14.  16. Electric motorization equipment according to any one of claims 11 to 14.  17. Electrical installation comprising a set of electrical equipment powered by an alternative voltage source and a set of touch control devices according to any one of claims 1 to 10, characterized in that it comprises at least one support part in insulating material comprising on an external face at least one tactile zone and on an internal face an electrically conductive zone connected to leakage current detection means, this electrically conductive zone being kept electrically isolated from any structure connected to the reference of neutral.  18. Electrical installation according to claim 17, characterized in that the support part (49) is maintained at a predetermined distance from a wall (41).  19. Electrical installation according to claim 18, characterized in that the support part (49) consists of a cover plate of a U-shaped part (44) made of an insulating material.  20. Electrical installation according to claim 19, characterized in that the inner face of the cover plate (49) has two side strips (46a, 46b) not covered with the electrically conductive coating.  21. A method for producing a touch control device according to any one of claims 1 to 10, characterized in that it comprises depositing an electrically conductive coating on the interior surface of a support part made of insulating material, the interior surface has a touch zone.  22. Method according to claim 21, applied to a hollow support piece of insulating material, characterized in that this deposition is carried out by the following steps:  - filling the hollow support piece with an electrically conductive solution comprising electrically conductive particles suspended in a binder,  - evacuation of this solution from the hollow support part, and  - drying of the interior of the hollow support part.  23. The method of claim 22, characterized in that the deposition steps are repeated until an electrically conductive coating of predetermined thickness is obtained.