FR2485772A1 - Fluid temp. mixing indicator - has valve body to include inlets, mixing chamber for fluid discharge and sensor for fluid flow - Google Patents

Abstract

This device relates to a system to provide a controlled temp. mixing of two or more fluids by an immediate visual indication of necessity for particular adjustment, and achievement of a predetermined fluid blend temperature range. The device includes plumbing fixture appts. comprising a set of manually controlled hot and cold fluid mixing valves and an integral fluid flow activated temp. sensor with electronic translation of fluid temp. imbalances between sensed blended fluid temp. and predetermined temperature values. A fluid temp. imbalance will cause illumination of a particular fluid control valve handle or handles to acknowledge and obtain corrective fluid temp. control by manually adjusting the fluid control valves until the proper fluid blend temp. range is achieved.

Description

 The present invention relates to a device which ensures the mixing, at a fixed temperature, of two or more fluids, because it gives an immediate visual indication of the operations which it is necessary to perform in order to carry out a particular adjustment and for obtain a predetermined interval of fluid mixing temperature.

 There are devices on the commercial market making it possible to measure or indicate the temperature of the water coming out of an ordinary tap. All these devices present the same type of difficulty, in that the temperature must be translated by the operator from mechanical measurement scales and in that no indication of adjustment is given. The temperature is obtained by reading a temperature scale and, therefore, this reading of the temperature is liable to error. The public, among whom one can find children, the elderly or individuals with very limited mental capacities, encounters difficulties in reading such temperature scales, and can easily make errors. The devices currently existing give no indication. direct to the user on the setting of the elements controlling the temperature which it is necessary to carry out to obtain a desired temperature range for the fluid.

Some prior art mechanical methods further require direct mounting on the fluid source, and many devices are too complex for them to be easy to operate and calibrate. Mixing valves with integrated mechanical temperature scales are described in United States Patent Nos. 2,171,992 and 3,960,016 and constitute representative examples of mechanical temperature cap turns combined with control valves.

 We know that, today, electronic temperature measuring devices, such as thermistors, have replaced mechanical tank and bimetal indicators. Electronic temperature measuring devices are precise and reliable and it is easy to translate their signals into various visual indications, especially in digital form. Examples of such devices are described in US Pat. Nos. 3,494,196, Nos. 3,857,285 and 3,927,571. All of these devices use electronic resistance temperature measurement which is translated and visualized by means of various known techniques. The above-mentioned devices may include two or more indicators, only one of which will light up to show the desired temperature state. However, in these patents, there is no is not alluded to a device or installation directly indicating the operations which it is necessary to carry out in order to achieve a particular control adjustment of a fluid mixing valve with a view to obtaining a predetermined state of mixing In addition, neither the processes described, nor the mixing valves with mechanical temperature indications or electronic temperature measurement can be compared to other processes, means or devices. for determining and communicating the desired setting of one or more fluid valves for obtaining an appropriate fluid temperature range and a desired temperature mixture ratio.

 None of these patents relates to a device for measuring and controlling a fluid temperature mixture, both mechanical and electrical, which only comes into service when a fluid flow occurs at the level of the detector element.

The prior art proposes mechanical as well as electrical fluid flow contactors associated with various techniques of signal translation, for example analog or digital, but these devices relate to the flow rate or to the composition of the fluid and not to conservation. of electrical power in a temperature mixing control device which, in its most practical form, must use, for operation, a current supply of limited duration, for example an electric battery. not detecting the flow may lead to false or error-causing readings for all these devices, which may, in return, lead to inappropriate indications regarding the adjustment operations to be carried out, at the same time as '' circuit deterioration due to continuous operation.

 At its most general level, the object of the invention is to propose an apparatus intended to give in a simple and precise manner the indication of the adjustment of the fluid control valves which makes it possible to obtain the desired fluid temperature and the mixture to be desired fluid temperature.

 According to another object of the invention, an apparatus is proposed which helps its user to adjust the fluid mixing valves in order to obtain the desired predetermined temperature range of the fluid formed by the mixture.

 Another object is to obtain indications on the necessary adjustment of the mixing valves in the only case where there is a flow of fluid at the outlet of the device, the intended advantage being to eliminate the erroneous indications or leading to the error and increase the possible duration of use of a low-capacity electrical power source, such as an electric battery.

 Another object of the invention consists in providing in the apparatus, a means by which it is possible to modify the illumination of the mixing control keys so as to be able to use the apparatus both when the ambient lighting is intense and when 'it is reduced. This characteristic is essential if we want to prevent losses on visual control indications in very bright environments, for example in sunlight, while allowing a reduced and pleasant visual perception in low light or in the dark.

 Another object of the invention is to provide a device using as indicator elements simple lamps to specify the correct fluid temperature interval and the incorrect interval and to indicate which valve must be turned to reach the appropriate interval. If used properly, the device helps the user to avoid the risk of scalding, scalding or the consequences of extremely cold temperatures.

 In particular, the visual display of the operations which must be carried out to adjust the mixing valves brings serious help to the public, to children, to tees, and to those who have sensory impairments. Among some typical uses, there are applications to mixing taps, for example in domestic, public or industrial installations, in particular showers and, moreover, any installation requiring the establishment of a temperature by mixing several fluids. In addition, it is envisaged according to the invention that the device can produce signals making it possible to actuate flow control valves with electrical operation having the task of controlling the flow rate in the event of the temperatures predicted being exceeded.

 The device contains no moving parts, so it is not susceptible to wear or mechanical failure. The device uses a low-consumption electronic circuit that includes electric resistance detector elements, a quadruple comparator and an associated control circuit producing an illumination output signal and an output signal for external use intended to provide additional controls.

The following description, designed to illustrate the invention, aims to give one. better understanding of its features and benefits; it is based on the accompanying drawings, among which
- Figure 1 is a plan view of an external embodiment of the device of the invention;
- Figure 2 is a side view of the external device of the invention;
- Figure 3 is a perspective view of an internal embodiment of the device of the invention;
- Figure 4 is a side view, partially cut away, of the internal device of the invention;
- Figure 5 is an electronic diagram of the device of the invention;
- Figure 6 is a block diagram of the external fluid control circuit of the invention;
- Figure 7 is a view of an internal embodiment of the device of the invention applied to a mixing control tap with a single key;
- Figure 8 is a side view, partially cut away, showing the internal device of the invention applied to a mixing control tap with a single key;
- Figure 9 is a perspective view of another internal embodiment of the device of the invention applied to another type of mixing control tap with a single key; and
- Figure 10 is an enlarged view of the temperature detection and fluid flow elements according to the invention.

 In Figure 1, we can see a tap 10 of fluid or water of the current household type, which includes a portion 12 for connection to the sink and a delivery spout 14. We also see the key 16 for controlling hot water and the cold water control key 18. After passing through the spout 14, the water comes out through the nozzle 20.

The lever 22 of the sink stopper is presented in the center of the part 12 for connection to the sink. A means for producing indication signals, formed by a control box 24 containing an electronic circuit for implementing the device of the invention, can be seen at the rear part of the lever connection part 12, as well as bulbs 26 and 30 serving as external indicator elements. An illumination adjustment switch 28 is arranged so as to make it possible to choose and regulate the intensity of the current applied to the bulbs 26 and 30 for a satisfactory visual perception. A detector probe 32, which is connected to the electronic components located inside the case 24, passes along the spout 14 and is held fixed at point 36 by a fixing collar 34.

 The detector device 32 is curved at a right angle at the point 36 so that it can pass under the spout 14.

The end 38 acting as a temperature-sensitive fluid flow switch is arranged below the nozzle 20 so that the fluid outlet from the tap takes place on the temperature measuring device and the temperature switch. flow at the end 38. A state of electrical resistance of the temperature measurement device and of the flow switch is then transmitted, via conductive wires placed inside the probe 32, to the electronic circuit of the case 24 .

 An outlet 40 is provided in case it is desirable to connect to the device a flow control mechanism, which is not shown in the drawings.

This mechanism would be fixed at a point located somewhere below the valve 10 in the fluid supply lines. In this hypothesis, if the temperature of the fluid exceeds, positively or negatively, a temperature corresponding to the needs of the user, the fluid control device, put into service by a signal from the device, would immediately reduce or interrupt the flow of the fluid. This device could be electrically connected to the electronic circuit of the case 24 via the outlet 40.

 The device of the invention operates in the following manner. The user sets the valves 16 and 18 to a degree of random mixing which seems to him to correspond to a desired temperature and flow rate. When the fluid passing through the tap has reached its temperature and its flow pressure, the flow is detected due to a reduction in the resistance existing between elements 38 of the probe acting as flow switch, which put in service of other electronic circuits of the housing 24 by means of a connecting cable passing inside the probe 32. The circuit thus put into service then samples the values of temperature of the fluid supplied by the probe 32 and a temperature measuring element disposed at 38. The electronic circuit of the housing 24 is preset so that, if the actual temperature of the fluid emitted by the nozzle 20 is within a certain interval of fluid temperature, this interval having been fixed previously, the bulbs 26 and 30 light up to indicate that a mixture at the appropriate temperature has been obtained. The preset interval can be changed in a manner which will be indicated below.

 If the fluid emitted by the nozzle 20 is for example too hot, then the bulb 26 lights up, but the bulb 30 remains off, which indicates, by lighting up the key 16, that the fluid is hot and that 'It is necessary to operate the cold fluid valve so as to bring the illumination of the key 18 of the cold fluid valve and thus make the outgoing fluid colder. In the event that the fluid emitted by the nozzle 20 is too cold, the bulb 30 lights up by lighting up the key 18 and the bulb 26 remains off, which indicates that the key 16 must be operated and adjusted until the key 16 lights up. When the desired temperature equilibrium has been reached, the bulbs 26 and 30 are both lit and therefore indicate that the keys 16 and 18 of the taps must no longer be operated. These two bulbs can remain on for as long as the interval desired temperature for the fluid is retained and there is a flow of fluid, or until an internal electronic timer circuit resets.

 In Figure 2, we can see the valve 10 of the invention and the key 16 for hot water control; the spout 14 projects from the part 12 for fixing to the sink. Figure 2 also shows a hot water inlet pipe 42 through which the hot water passes to reach a mixing valve (not shown) for mixing hot water and cold water, which arrives by a cold water pipe, after which the liquid arrives at the outlet nozzle 0 via the spout 14. The temperature measurement and fluid flow detection probe 32 passes along the spout 14 and is firmly fixed to this by a collar 34. It passes under the spout 14 at the point 36, then descends, via an arm 44, so that it can be placed below the nozzle 20. The end 38 extends under the tap so that the water falls on the end 38 when it comes out. The end 38 is screwed to the probe 32 at the point 45.

 The control boot 24 is mounted at the rear of the tap 10 and of the part 12 for connection to the sink by means of an L-shaped flange 46 which is permanently mounted on the connection part 12 to the sink by means of a suitable element, for example a screw or a bolt 48.

Another screw, or else a set of screws, 50 secures the case 24 on the flange 46. The bulbs 26 and 30 appear on the case 24, as well as the outlet 40 and the lighting switch 28. The case 24 has a rear cover 52 which can be removed to modify or adjust the electronic circuit located inside the case 24.

 The embodiment which has just been described can be attached to any existing sink tap of a household or public installation, and it can also be used with taps having only one adjustment key. temperature only with taps with two keys. The bulb indicator elements retain, in the case of a single key, the function of indicating in which direction to operate the key to obtain the appropriate water temperature.

 In addition, it may be considered to reverse the positions of the bulbs 26 and 30 internally to show by direct lighting a particular key, 16 or 18, the adjustment to be made, the choice being at the discretion of the users.

 FIG. 3 describes how it is possible to mount the device of the invention inside a new tap so that the whole of the means producing indication signals is contained inside the tap itself .

 As shown in Figure 3, the conventional sink valve 54 has a portion 56 for connection to the sink, a spout 58 and an outlet nozzle 60. A water inlet hose 62 hot and a cold water inlet pipe 64 bring the water to the tap to ensure the final mixing in a mixing valve 66, of which only a part is presented. The water then passes through the spout 58, via a pipe 68, which rises to the center of the decorative outer casing to finally reach the outlet nozzle 60. The handle 70 for controlling the sink stopper is located at middle of the part 56 for connection to the sink. The electronic circuit of the invention is located in a control box 72 which is, in this case, located inside the part for connection to the sink of the tap. 54 The housing can be fixed to the tap by any means, for example by bolting. The detector probe 74 leaves the control case 72 and rises along the outlet pipe 68 as far as the spout part 58. At a given point close to the end of the outlet pipe 68, there is a hole 76 in the pipe , and the temperature measurement device is placed in this hole 76 so that its end 78 for flow detection and temperature measurement extends directly inside the fluid outlet pipe 68. The hole 76 is naturally closed tightly around the probe by any known means, for example a sealing ring.

 The indicator elements with valve adjustment bulbs can then be placed inside the device if the fluid control keys such as the hot water control key 80 and the cold water control key 82 are made in a transparent or luminescent material, for example plastic. In this way, the bulb 84, which indicates that the water is too hot and that cold water must be supplied, can be placed inside the valve, so that when the bulb 84 lights up, it can be seen through the key 80. A bulb also exists under the cold water control key 82 so that, when the water is too cold, which requires the delivery of a larger quantity of hot water and, consequently, causes the elimination of the key 82 for controlling cold water, the key 80 must be operated to bring about the elimination of the bulb 84.

 When the temperature and the flow rate of the water are correct, the bulb 84 and the bulb placed under the bulb 82 light up and are visible to the user through the keys 80 and 82. Thus, this device operates in the same way as the external device shown in Figures 1 and 2, except that the electronic circuit and the bulbs are placed inside the valve.

 In Figure 4, we can see the tap 54 with its part 56 for fixing to the sink and its spout 58 terminated by an outlet nozzle 60. The pipe 62 for hot water supply brings hot water in the tap, this hot water being mixed with cold water in the mixing valve 66. The water then leaves the device through the outlet pipe 68.

 The detector probe 74 leaves from the control unit 72 and passes through the hole 76 so that the end 78 of flow detection and temperature measurement is on the path of the water passing through the outlet pipe 68.

 The hot water control key 80 is mounted so as to control the flow of hot water and, as indicated, is made of a transparent or luminescent material so that the illuminated bulb 84 can be seen through the key.

 The box 72 containing the electronic circuit is permanently mounted inside the valve 54 by any means, for example a bolt 90. When the water reaches a correct temperature, the bulb 84 and the bulb being under the opposite key (this bulb not being shown) light up so that the user is immediately able to tell that the water temperature is then in the correct range.

 An illumination adjustment switch 86 is provided to allow the choice and regulation of the current flow applied to the bulb 84 and to the bulb placed under the opposite key and allow obtaining a satisfactory visual perception.

 If we consider the scope of the invention, it will be understood clearly that the bulbs, or the indicator elements by emission of light, which serve to indicate if its temperature is too high, if it is too low or if it is in a correct area, can be replaced by acoustic signals when users are unable to observe them, either because they are blind or have very poor vision, These acoustic signals can have different heights to indicate if the water is too hot, too cold or at the correct temperature. In the device, the entire electronic circuit is inside the control unit 72, so that it is not necessary to place separate acoustic elements outside the taps. We can also consider another case, that of a person who is both blind and deaf; in this case, it is possible to replace the indicator devices described above by vibration generating elements which would then be placed inside each of the keys to indicate which of the keys should be set to correct the temperature imbalance, such a vibration generating mechanism can be used in the valve itself so that a person can say, being the various parts of the valve, and before d '' having placed his hand under the jet coming out of the tap, whether or not the fluid is in the correct temperature range.

 In FIG. 5, a schematic representation can be seen of the means producing signals for indicating the invention. The device comprises four basic elements: a detector device, a quadruple comparator, indicator elements and a source of electrical energy. The sensor is a two-element device whose resistance varies as a function of the temperature applied to the surrounding glass envelope and which detects, by lowering the resistance, the flow of fluid between the exposed ends of the In the case of the flow detector, variations in the resistance modify a voltage at the detector input of a single element of the quadruple comparator behaving as an electronic switch allowing the commissioning of a current switching transistor means which supplies the current source of the temperature measurement comparators and of the associated switching transistors used for the illumination of the bulbs. A temperature measuring element, which can most often be a thermistor, is placed in common on the measurement inputs of two other parts of the quadruple comparator, each having a different polarity on which variations in the detector resistance cause variations in These variations belong to a reference voltage range and are interpreted electronically by the comparator circuit. The center of the desired points for switching the maximum threshold and the indication temperature is fixed by a single common reference source with voltage divider. The comparator output signal directly expresses whether or not an appropriate voltage has been applied to its input. The output signals are applied one by one to an output control circuit which produces the conditions which are presented to the user as indications to display the settings necessary for obtaining different temperature intervals. In the broadest sense, this corresponds to an increase in the flow of cold water, an increase in the flow of hot water or an absence of operation of the keys. With a suitable arrangement with regard to taps, the indications specify which valves must be adjusted to produce the desired temperature.

 As shown in Figure 5, the fluid flow detector 114, which includes two special metal probes, translates the flow of the fluid as a reduction in electrical resistance between the elements. Such a device is not commonly used, but it can easily be constructed from two corrosion-resistant wires spaced a suitable distance from each other. The signals emitted by this device appear at the level of the comparator 110 and are used to activate a switching transistor 116 of the PNP type with medium current silicon, which in turn serves as a source for the temperature measurement and indication parts. .

 The resistance sensing element 92 is a temperature sensitive semiconductor resistor which is encapsulated in hard glass. These devices are well known and constitute the most commonly manufactured resistance sensors.

 Interval selection resistors 94 are chosen so as to give a desired temperature interval over which the indicator lights are turned on. It is possible to modify this interval by changing the value of the resistors 94 or by using a variable resistance or an adjustable potentiometer so that the user can modify the interval himself.

 The temperature comparator circuits include three comparator units, designated respectively by the references 96> 98 and 112, and-commonly called under the commercial designation "lob39" by many producers. When they operate at low drain current, they can be replaced by equivalent CMOS comparator elements. The output signals of these devices are applied to the switching transistors 106 and 118, which are typically P-N-P type silicon devices with medium current which are very easily found on the market. Bulbs or light emission sources 100 and 102 provide the indication of the necessary adjustment of the valve keys. An output socket 120 communicates decoded output signals for external control.

 A resistor 122 for limiting the current of the indicator elements, placed in series with the battery 108 serving as a source of electricity, can be adjusted manually to give the level of illumination of the indicators which ensures the most satisfactory visual perception depending on whether the ambient lighting is intense or weak.

 The source of electrical energy can be a battery 108 or a standardized laboratory power supply, the current flow being very low due to the use of devices with low power integrated circuits.

 Figure 6 shows a block diagram of an external fluid flow control mechanism which can be actuated by the electrical state of the comparator output signals.

The state of the signals from the comparator actuates electromechanical valves 130 and 132 placed in the pipes 136 of the fluid supply of the plumbing installation 134. The signals 138 are taken from an outlet outlet of the installation 134, thus as has been explained previously.

 FIG. 7 shows the use of the invention in a tap 140 for controlling mixing with a single key, comprising a part 142 for connection to the sink, a movable pouring spout 144 and an outlet nozzle 146. The pipe 148 hot water inlet and cold water inlet pipe 150 conduct the fluid to the tap, where cold water and hot water are combined by a mixing valve 152, only part of which is represented.

The fluid current then passes through a pipe 154 to exit through the spout 144 at the outlet nozzle 146. The means producing indicator signals according to the invention is contained in a control box 156 located inside of the part 142 for connection to the sink. The detecting probe 158 extends out of the control box 156 to reach the movable spout 144, where a hole 160 gives access to the pipe 154.

 The control box 156 contains the electronic circuit enabling the apparatus according to the invention to operate and is located at the rear of the part 142 for connection to the sink. The lamps 162 and 164, shown lit, are fixed to the control box 156 and protrude into the part 142 for connection to the sink.

 The temperature control is carried out by rotation of a single lever 166 for controlling the mixture in the direction indicated by illumination of the bulb 162 or of the bulb 164.

 In Figure 8, we can see the valve 140 according to the invention comprising a lever 166 for mixing control and a movable spout 144 projecting from the part 142 for connection to the sink. We can also see the hot water inlet pipe 148 through which 11 hot water passes to reach a mixture control valve 152, while there is a similar pipe for cold water. The flow of fluid then arrives, via the movable spout 144, up to the outlet nozzle 146. The detecting probe 158 leaves the control unit 156 and, through the hole 160, arrives in the pipe 154 so that the end 158 for flow detection and temperature measurement is located directly in the fluid flow. Control box 156 is mounted internally and connected to light bulbs 162 and 164 on, light bulb 164 not being shown on Figure 8.

 Figure 9 is a view of the device of the invention when it consists of a mixing control tap 170 with a single key, so that the device of the invention is mounted entirely inside the tap himself. The pipe 172 for hot water inlet and a pipe 174 for cold water inlet convey the fluid as far as a mixture control valve 176, of which only a part is shown. The water then reaches the movable spout 178 to finally exit through the outlet nozzle 180. A means producing indicator signals, which consists of a control unit 182, is housed inside a part 184 of connection to the sink and includes bulbs 186 and 188 (only the bulb 186 being shown) which are placed inside the key 190 of the mixing control valve. When one or other of the bulbs 186 and 188 is lit, it can be seen through the handle 192 of the tap key; this can be made of a transparent or luminescent material, for example plastic. Two bulbs of two different colors, for example red and yellow, red corresponding to hot and yellow corresponding to cold, can be used and, when the two bulbs produce a third color, namely orange, the temperature is in the correct interval. Thus, the device operates in the same manner as has been described in connection with FIGS. 3 and 4, with the exception that only one tap control key is used.

 In FIG. 10, one can see an enlarged view of the temperature measurement and fluid flow detection element according to the invention. The fluid flow sensor 200- is formed by two special metallic probes, parallel aligned, which are separated by a determined distance. The resistant temperature measurement element 202 is mounted in association with the sensor 20Q on a fluid sealing disc 204. Electrical wires 206 make it possible to transmit variations in electrical resistance to the control unit, the latter not being shown.

 Of course, those skilled in the art will be able to imagine, from the devices whose description has just been given by way of illustration only and in no way limitative, various variants and modifications not departing from the scope of the invention.

Thus, different arrangements of indicator bulbs 100 and 102 may be more effective, other valve adjustment lamps may be instructive, or colored arrangements of valve lamps may be made interestingly in a single element. In addition, the invention applies equally to mixing valves with a single element as with normal valves with two control keys.

Claims (12)

1. Device for plumbing installation comprising a fluid valve device comprising control keys (16, 18) used to control and combine hot and cold fluids, a valve body comprising the fluid inlets and a mixing chamber, as well as a fluid discharge outlet, the device being characterized in that it further comprises an indicator signal producing means (24) which works integrally with the installation to determine and communicate the exact corrective action necessary for obtaining predetermined fluid temperature intervals, said indicator signal producing means comprising an electronic signal converter comparator circuit, which translates the detection of the fluid flow and the measurement of the temperature of the fluid into predetermined electrical indications, said comparator circuit producing a signal output state which depends on the fluid discharge temperature and the presence of a fluid flow signal, said comparator circuit consisting of a first and a second comparator, which each have a separate input of opposite detector polarity, connected in commu to the output of a resistive element (38) sensitive to the voltage division temperature which is placed in the fluid discharge path and a separate detector-input which is fixed to a single preset voltage division reference source which determines both the center of a temperature interval d indication and the maximum threshold width from the center of the indication temperature range, the output signals of the first and second comparators actuating separate and parallel switching transistors which, in turn, produce a source of current intended to light up indicator elements (26, 30) with light bulbs arranged at control keys as a function of the amplitude of the input signals, a third comparator poss edant a separate detector input connected to the outputs of the first and second comparator by addition resistors and having a second separate detector input linked to a preset voltage reference source which produces an output action when the state- of said circuit is such that the first and second temperature measurement comparators are non-conductive and therefore indicate that a fluid temperature equilibrium has been reached, the action at the output of the third comparator producing a signal intended for the two transistors of switching in order to light up indicator elements on all control keys to indicate that no adjustment of control keys is necessary and that the appropriate fluid temperature has been reached, commissioning and operation of all the comparators and the described temperature measurement circuits dependent on a fluid flow switch (38) which consists of an element exposed resistive element placed in the fluid discharge path so that another comparator transfers the detected fluid flow resistance into a switched current source intended for the comparators and described temperature measurement circuits, the means producer of indicator signals comprising said comparators and temperature measurement circuits, which indicate an imbalance in the temperature of the sampled fluid occurring during an active fluid flow and in relation to a predetermined temperature interval> said means producing indicator signals indicating one or more specific corrective actions making it possible to obtain an appropriate fluid temperature interval by manual adjustment of fluid control valves indicated by indicator elements located at the level of the control keys. 2. Device according to claim 1, characterized in that the indicator elements are lighting elements, such as filament lamps or light emitting diodes. 3. Device according to claim 2, characterized in that the lighting of said indicators is carried out in direct arrangement with the control keys of fluid valves so as to indicate the adjustment of the particular valve which must be carried out to obtain an interval desired temperature 4. Device according to claim 3, characterized in that a radiation light arrives on the valve control key. 5. Device according to claim 3, characterized in that a dispersion lighting is projected into said control key. 6. Device according to claim 1, characterized in that the temperature sensor and the fluid flow switch, which consist respectively of a temperature-sensitive resistor and of a fluid resistance sampling element, are mounted integrally along the flow path of the fluid at the discharge. 7. Device according to claim 1, characterized in that it comprises temperature measurement and fluid flow detection elements, a logic circuit of electronic conversion with low electric consumption, command determination indicators, and a electrical energy source designed to be used in connection with an ordinary tap through which a fluid with adjustable flow passes. 8. Device according to claim 1, characterized in that it comprises a means producing indicator signals which indicates that a stable fluid temperature interval has been reached by means of a single light source or sources illuminated multiple. 9. Device according to claim 3, characterized in that it makes it possible to choose the level of radiant lighting emitted by the indicating elements so as to produce a satisfactory visual perception in conditions of intense ambient lighting and of weak ambient lighting thanks to a current limiting resistor placed in series with the electrical source. 10. Device according to claim 1, characterized in that the comparators are voltage comparators.  He. Device according to claim 1, characterized in that it comprises a single-control mixer tap containing said means producing indicator signals, by which the control adjustment indications and the obtaining of a desired fluid temperature mixture can be obtained. 12. Device according to claim 2, characterized in that said illumination consists in the emission of colored lights describing the operations which it is necessary to carry out to control or obtain a mixture of appropriate fluid temperature. 13. Device according to claim 1, characterized in that the output signals from the comparator circuit are supplied to an external fluid control device via an output socket, whereby the electrical state of the signals of the comparator circuit controls electromechanical valves which regulate the flow of fluid in direct relation with the supply means of the plumbing installation. 14. Device according to claim 13, characterized in that the external fluid control ensures the regulation of the temperature of the fluid mixture at the discharge by means of said electromechanical valves.