EP1007810A1

EP1007810A1 - Method for servicing the water of a swimming pool and device for implementing same

Info

Publication number: EP1007810A1
Application number: EP98913878A
Authority: EP
Inventors: André GOLA; Philippe Billaud
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-03-10
Filing date: 1998-03-10
Publication date: 2000-06-14
Also published as: US6228272B1; FR2760483A3; WO1998040585A1; CA2283679A1; FR2760483A1

Abstract

The invention concerns a method and a device for servicing the water of a swimming pool (1) by adding a disinfectant, consisting essentially in automatically controlling the addition of the disinfectant based on the sensing of the water temperature. The operation is carried out by treating the water in a branch circuit of the pool, in which the water is circulated at a constant flow rate, by sampling and recycling of the pool, by means of a pump (5) with a constant flow rate, for an operating time which is process-bound by said temperature sensing. Preferably, this operating time is determined according to a preset programme and consisting of time slot units of similar duration spread over several time ranges.

Description

METHOD FOR MAINTAINING WATER IN A SWIMMING POOL AND DEVICE FOR CARRYING OUT THIS METHOD

The present invention relates to a method and a device for the maintenance of water in a swimming pool. Its main purpose is to automate the operations that are necessary to maintain the water contained in swimming pools under sanitary conditions appropriate for its use.

Beginning by considering the case of the preferred application of the invention to individual swimming pools, which is that of swimming pools that people commonly install in their garden for swimming there, it will be observed that the characteristic of such swimming pools is to have undergo regular disinfection of the water it contains in order to stop the proliferation of the bacterial flora which develops there. It should be added that the large quantity of water, the installation conditions and the economic requirements combine to prohibit the use of a real permanent renewal of the water, so that in practice, the maintenance of the Sanitary cleanliness is done by taking water from the pool to pass it through an external circuit which purifies it, generally by filtration and by adding a disinfectant, before reinjecting it thus purified in the same pool.

It follows that the invention is not limited to this particular type of swimming pool and that its applications extend to many other fields in which the same kinds of needs are felt.

Among the other swimming pools which it will be advantageous to equip in accordance with the invention, one can quote for example the basins of the thermal centers, the basins being used for the bathing of animals or the breeding of fish, those being used for the cultivation of fragile plants. These basins, which the invention encompasses under the notion of swimming pool, can be very varied in their form, their depth and their capacity. Similarly, when we speak of an addition of disinfectant in the context of the invention, the concept must be understood as being able to cover the case of any constituent that should be added to the pool water. to regenerate it to the desired content, for example to compensate for its consumption or its destruction as and when the use of the pool.

By its various characteristics, as they will be more fully defined and described below, the present invention considerably simplifies the management of swimming pools, in particular individual swimming pools, while overall reducing the cost of their maintenance. Thanks to the automatic adjustment they provide, the user no longer has to intervene to adjust the dosage of disinfectant according to the conditions which influence its consumption, and there is no longer any risk of making disorderly, insufficient or untimely additions.

The invention does not, however, involve measuring the content of disinfectant in the pool water. Therefore, as well as by a good number of other provisions, the invention requires for its implementation only a simple material, inexpensive and of solid construction, while providing good operational safety for sufficient accuracy. . In addition, this equipment is easy to install and easily adapts in addition to the water purification and regeneration equipment already present in an existing swimming pool installation.

To achieve the objectives it has thus set itself, the invention essentially consists in regulating the addition of the disinfectant (or other purification or regeneration agent) by acting on the quantity of water which is withdrawn and recycled via the purification circuit for a given period of time (or unitary period), by controlling the organs which ensure its circulation as a function of the detection of a quantity measurable which is in one-to-one relationship with the disinfectant content required in the pool water.

According to one of the characteristics of the invention, said measurable quantity is advantageously the temperature of the swimming pool water. Its measurement is very easy. It is sufficient in particular for a temperature sensor placed on the bypass pipe constituting the purification circuit. And one can easily determine, by experience and calibration, a one-to-one relationship between this temperature and the purification and regeneration regime to bring the pool water back to the appropriate sanitary conditions. It does not matter in this regard that a rise in temperature, for example, is at the origin of an increase in bacterial proliferation, or that it is on the contrary the consequence thereof, or that it is linked to a number unusual visitors. In all cases, it automatically causes the necessary addition of disinfectant.

It is therefore understood that, thanks to the invention, it is not necessary to know the value of the disinfectant content itself. In a way that can be said to be symmetrical, the invention also makes it unnecessary either to directly order the injection of a metered quantity of disinfectant, insofar as, according to another characteristic of the invention, its incorporation takes place in the purification circuit bypassing the swimming pool, in a manner naturally linked to the quantity of water withdrawn and recycled per unit time period.

Note that it is not essential that there is a proportional or otherwise known relationship between the amount of water thus treated and the dose of disinfectant injected therein. Here too, in practice, and at least in the most common circumstances, there is self-regulation through microbial proliferation exacerbated by insufficient disinfectant, with its consequences on the detected temperature, so that an experimental calibration is sufficient to ensure satisfactory operation in most situations.

In its preferred embodiments, the invention exploits the fact that many disinfecting agents commonly used in the maintenance of swimming pool water are introduced with the aid of material means through which the circulating water passes. This is the case in particular of "rollers" which release chlorine on contact with water and its dissolving power, or chlorine generators proceeding by electrolysis of a sodium chloride solution. Chlorine production then takes place only when the water is circulated in the treatment circuit.

Other important features of the invention mainly relate to its applications in the field of swimming pools for private use. As these pools are used intermittently, it is desirable that the water treatment circuit does not operate continuously, but on the other hand, it is desirable that each time, it operates for a time sufficient to stir all the water in the pool. In other words, this operation lasts long enough to treat a volume of water corresponding substantially to that contained in the pool.

The invention therefore advantageously takes the form of an automatic management device for water pool maintenance operations in an installation comprising, in a conventional manner, a stirring pump, with drive controlled by all or nothing, for conveying water from the swimming pool in a treatment circuit connected in a closed loop to the swimming pool and comprising means for injecting a disinfectant agent into said circuit, said means preferably being such that in normal operation the flow rate of disinfectant agent added depends only on the flow of circulating water provided by the pump. In accordance with various characteristics, which are here to be considered separately or in any technically effective combination, such a device according to the invention comprises a temperature sensor mounted on said circuit to be sensitive to the temperature of the water taken from the pool and of the means slaved to said sensor for controlling the operation of the stirring pump at a predetermined constant flow rate for a variable duration as a function of the temperature detected by said sensor, this variable duration advantageously corresponding to an integer number of sequences (or time slices) of duration fixed predetermined, said variable duration being calculated to circulate in said circuit a total volume of water substantially equal to the water capacity of the pool.

Preferably, the operation is ensured according to pre-established programs, distinguished in particular by a daily number of brewing sequences of the same unit duration, among which the choice is determined by automatic selection according to predefined contiguous ranges of measured temperatures, according to that in which the temperature determined by the sensor is located.

Preferably also, the temperature detection is carried out periodically on the treatment circuit, at the start of a brewing sequence, with a time delay enabling validation of a measurement of the temperature of the water in the swimming pool determining the duration of stirring to be ensured at a given time, in particular the total daily duration.

It is also advantageous to provide safety operating programs, the triggering of which can be either automatically controlled by the same electronic circuits ensuring the regulation of the addition of disinfecting agent in normal operation, for example so that, if the temperature detection reveals a measured value which is below a minimum risk of freezing value and / or if it is above a maximum risk value of intense pollution, the brewing pump works continuously either manually, for example so that the user can start the brewing pump voluntarily and thus cause a temperature measurement which will cause if necessary a change of daily program, when he suspects an additional pollution risk

(falling leaves in the swimming pool, intense sunshine, etc.), or even made automatic by other control circuits, which will be the case, for example, if the device of the invention intervening in so-called normal regulation is coupled to an outside temperature detection system which controls the starting of the pump if this temperature exceeds a determined threshold. In all cases, the device according to the invention can be equipped to generate an alarm signaling the safety condition.

According to another characteristic which advantageously applies to the device of the invention, the stirring pump takes the water circulated in the treatment circuit by suction, partly at the bottom of the swimming pool and partly at the surface, the two parts being mixed upstream of the temperature detection, so that the measured temperature which controls the determination of the treatment times is representative of an average temperature prevailing in the swimming pool.

The invention will now be more fully described in the context of preferred characteristics and their advantages, with reference to the figures of the appended drawings which illustrate them and in which: - Figure 1 schematically illustrates an overview of an example of device according to a preferred embodiment of the invention and of the swimming pool maintained by this device;

- Figure 2 illustrates the mounting method of a water temperature sensor, used by the device of Figure 1; - And Figure 3 is a block diagram of the electronic circuits of the device of Figure 1.

FIG. 1 is a flow diagram schematically illustrating the automatic maintenance management device according to the invention and thus showing the swimming pool, its water regeneration members and the means for regulating the conditions of water maintenance by adding disinfectant.

More specifically, the assembly is typically grouped into two main sub-assemblies: on the one hand the swimming pool proper 1, equipped with a bottom drain 65, with a surface suction mouth incorporating a roller of disinfectant, or "skimmer" 64, and a mouth for recycling the treated water, on the other hand a technical room 2, close to the swimming pool, in which are located the mechanical and electronic equipment necessary for the maintenance treatment of the pool water and its regulation.

The water treatment circuit passes from one to the other of the two aforementioned sub-assemblies. We see that this circuit, in which the water is conveyed by a so-called stirring pump 5, comprises a water suction pipe

61, here split to take water partly at the bottom of the pool by the drain 65 and partly at the surface by the "skimmer" mouth 64, and a discharge line 60 which recycles the treated water in the swimming pool, passing through a filtration member 63. A temperature sensor 30 is mounted on the circuit thus constituted as a bypass of the swimming pool.

It has also been shown in this figure that the suction pipes 61 are associated with a valve

62. This ensures mixing in a constant ratio between the flow coming from the bottom drain and the flow coming from the suction inlet at the surface. Thanks to this function, which is located upstream of the temperature, it is ensured that the detected temperature sent as a measurement signal to the regulation circuits is representative of an average temperature of the water contained in the pool which remains faithful to the calibration conditions. As a variant, a similar valve system, associated with manual local control means or with motorization and remote control means can also be used to allow the same equipment implementing the invention to establish control regimes. particular functions, which are differentiated, for example, by a privileged aspiration from the surface of the surface water of the swimming pool towards the treatment circuit.

Furthermore, no other valves and pipes have been shown which are intended, in a conventional manner, to allow the pump to be isolated from the entire circuit, to cause circulation in the opposite direction with setting to 1 ' sewer for periods of cleaning the filters, to allow maintenance or replacement of the mechanical components, to ensure the operations of emptying and supplying fresh water.

The circulation of water in the circuit 60-61 is ensured by the pump 5, which is driven by an electric motor (not shown). This pump operates at constant flow, but the flow naturally depends on the size of the installation. The disinfecting agent is dispensed, in the particular case illustrated, by the chlorine diffusion roller at 64, which is only operative when the pump 5 circulates the water in contact with it. However, as a variant, other regeneration systems can be used, in particular those proceeding by electrolysis, which will then be placed no longer upstream of the pump 5 but downstream, more precisely downstream of the filter 63, because they require that the water has been freed of the solid particles that it can contain at the outlet of the pool. For regulation, the device specific to the invention essentially comprises a control and display unit 3, incorporating electronic circuits which will be described in detail below, with reference to FIG. 3, and which receive the electrical signals Vs emitted by the temperature sensor 30, which translate a measurement of the water temperature which is carried out periodically according to methods which will also be specified below. In a conventional manner in itself, the technical room 2, or what makes it function, also includes an electrical cabinet 4 for supplying electrical energy to the various components of the device 3 and of the pump motor 5.

FIG. 2 illustrates a possible mounting mode of the sensor 30 on the suction pipe of the pump 5.

The sensor 30 is downstream of the valve 62. It comprises a body

300, consisting of a casing of any shape, and the temperature-sensitive element 301, which must be immersed in the water which circulates in the pipe 61. Assuming that the pipe 61 is based on plastic material, for example example in polyvinyl chloride, it suffices to pierce this pipe 61, to insert the sensitive element 301 there and to glue the box 300 using an appropriate glue. The cable carrying the output signals 302 can be secured along the pipeline using one or more clamps 8.

Typically, the control unit 3 comprises, on its front face, a display member 31 (for example with liquid crystal or plasma), an indicator 33, of green color for example, indicating the starting of the pump 5 ( marked "OK" for example) and an alarm light 34, red in color as usual (marked "ALARM" for example). The display member 31 has a dual function: alternating display of the time and of the measured water temperature. (Re) setting the time and switching from one display mode to another is carried out by pressing a push button 32. Conventionally, it can be provided that after a predetermined period of time following a time reset, the display member 31 automatically switches to temperature display mode.

The electronic control circuits, forming with the temperature sensor the main part of the device according to the invention, are grouped together on a printed circuit board 7, of conventional type per se and advantageously meeting the standards in force in a given country, for example conforms to CE standards for France. The various components used advantageously meet industrial type specifications. In particular, they must operate in a temperature range from -40 ° C to +50 ° C.

The electrical power supply to the circuits located on the printed circuit board 7 is provided by a transformer 77 connected to the mains (for example on a 220 V socket, not shown) which delivers a very low voltage, typically 6 V. That -this is rectified and regulated by conventional circuits, under the single reference 76. The transformer 77 is of a high insulation type (typically greater than or equal to 4000 V) and is protected by a varistor (for example having a voltage of 275 V) and a fuse, typically 3 A. The latter value is dependent on the nominal power used. These provisions are useful so that the circuits comply with the safety standards in force. They naturally depend on the specific application and the country of use.

The electronic control and signal processing circuits specific to the invention are produced, in the example described in FIG. 3, using three integrated circuits: a microcontroller 70, a time base 71 and a clock 72 called real time. As is well known, these electronic components communicate with each other via a bidirectional data transmission bus. The components of the card, in particular the microcontroller 70, receive signals from the temperature sensor 30 and the push button 32. They develop control and signaling signals transmitted to the indicator 33, to the display member 31, for the display of the temperature measured by the sensor 30, and to electromagnetic relays 74 and 75, for controlling the pump 5 and for controlling the alarm lamp 34, respectively.

The output signals are transmitted to the receiving organs directly or via amplifiers or conventional adaptation circuits, not shown. Similarly, if the temperature sensor 30 does not include analog-digital conversion circuits, and amplification and / or adaptation circuits, such circuits are provided on the card 7, the microcontroller 70 processing only standardized binary digital signals. It is possible to provide a specialized port (not shown) comprising conversion circuits. Otherwise, you can go through a connection to a serial port, for example.

The configuration of the circuits of an example device according to a preferred embodiment being recalled, we will now describe the main characteristics of the method for maintaining the water in the swimming pool 1 according to the invention in one embodiment. particular.

According to a first important characteristic of the invention, measurements are made periodically of the temperature of the pool water 1 by means of the sensor 30. The output signals V _s are proportional to the amplitude of the measured temperature and they include information on the sign of this temperature. After conversion as necessary, they are transmitted to the microcontroller 70 for processing and elaboration of control orders for the stirring pump 5. In practice, the taking into account of the measured temperatures is carried out according to a minimum rhythm of predefined time periods. , for example at the start of each brewing period or every hour. The measurement is validated after a time delay determined after the start of brewing so that it indicates the actual temperature of the pool water, for example after 5 minutes.

According to a second important characteristic of the invention, the daily duration of stirring of the water, and therefore of filtration and addition of disinfecting agent depends on the different temperatures recorded and treated by the microcontroller 70. The total daily duration of stirring thus determined is then distributed over predefined time slots according to the options of pre-established treatment programs.

In a preferred embodiment, a predetermined maximum number of tracks is defined, for example a maximum number of three daily tracks, it being understood that the duration of each track is of variable amplitude, or even zero, depending on the program selected. This individual duration is also determined by program, so that the sum of the individual durations reaches the desired overall daily treatment duration. It is also expected that each duration in a determined time slot is at least sufficient to circulate in the treatment circuit a total volume of water substantially equivalent to the capacity of the pool, and further that each is equal to an integer time slots all equal to a unit duration, which will be one hour of real time for example.

To fix the ideas, and without this being in any way limiting the scope of the invention, the table below provides an example of a series of pre-established programs, indicating for each the daily duration of brewing as a function of the temperature recorded by the sensor and the distribution of this total duration in numbers of one-hour sections (or sequences) as they are distributed over three time slots located respectively in the morning, in the afternoon and the evening of every day. In practice, the selection of the program is carried out on the basis of a comparison between the temperature recorded and taken into account and the contiguous predefined temperature ranges.

Range ° C Duration Distribution Temp. Program Morning A.. Daily evening

° C h / d Sequence number: s Hours

<3 24 Continuous operation (=> ALARM)

3.1 to 6 2 2 0 0 8h - lOh

6.1 to 9 3 3 0 0 8h - llh

9.1 to 12 4 4 0 0 8 a.m. - 12 p.m.

12.1 to 15 5 3 2 0 8 a.m.-11 a.m., 2 p.m.-4 p.m.

15.1 to 18 6 3 3 0 8 a.m.-11 a.m., 2 p.m.-5 p.m.

18.1 to 21 7 4 3 0 8 a.m. to 12 p.m., 2 p.m. to 5 p.m.

21.1 to 23 8 4 4 0 8 a.m. to 12 p.m., 2 p.m. to 6 p.m.

23.1 to 26 10 2 4 4 3-5h, 8-12h, 14-18h

26.1 to 28 12 4 4 4 3-7h, 8-12h, 14-18h

28.1 to 30 14 4 4 6 3-7h, 8-12h, 14-20h

30.1 to 31.9 16 4 4 8 3-7h, 8-12h, 14-22h

> 32i Continuous operation (=> ALARM)

Examination of the table shows that extreme climatic conditions or conditions of use of the swimming pool 1, which result in a water temperature T, ie below a first threshold (r <3 ° C) , or above a second threshold (T> 32), cause permanent mixing of the water and a maximum daily filtration period of 24 h. Detection of these extreme conditions also triggers an alarm. The microcontroller 70 will generate an alarm signal transmitted to an electromagnetic relay 74 which supplies the alarm indicator 34. This indicator 34 is connected, via the contacts of relay 74 on the mains. Indicator light 34 remains permanently on. If necessary, other types of alarms, visual and / or audible, can be provided. Concurrently with the alarm signal, the microcontroller 70 generates a signal transmitted to a second electromagnetic relay 75 which connects the electric motor of the pump 5 to the mains. As indicated above, the alarm signal is permanent until the abovementioned extreme conditions disappear or until an authorized operator has stopped the device by any appropriate means, switch, etc. (not shown). In all other cases, which will be considered to be part of normal operation, the indicator 34 is not supplied. The total filtration time is determined by a program pre-recorded in the microcontroller 70 and distributed over the predefined distinct time slots. The daily duration of normal treatment is between minimum and maximum values (2 hours and 16 hours, respectively, in the example described).

The microcontroller 70 cooperates with two other circuits, 71 and 72, as indicated. Depending on the temperature detected, the microcontroller 70 generates binary command words which are transmitted to the circuit 71. The latter is a programmable time base which generates a signal of variable duration, depending on the binary configuration of the command words presented. at its entrance. A specific configuration forces the time base to generate a permanent output signal. The output signals are transmitted to relay 75, directly or via amplification and / or shaping circuits (not shown). If the daily cycle is divided into separate ranges, as is the case in the preferred embodiment of the invention (three ranges in the example described), the microcontroller 70 transmits a command word to the time base 71 at the start of each track.

It is understood that the duration of one operation over a determined time slot can be zero, as shown in the table above. Apart from extreme conditions, low and high, whenever the pump 5 operates, a signal is generated by the microcontroller 70 and transmitted directly or via an amplifier and / or a shaping circuit (not shown) to the indicator 33.

The third circuit, 72, consists of a real time clock. Indeed, this circuit 72 is supplied autonomously, by battery or battery, so as to determine the time which elapses in the event of a mains failure, thus ensuring a time-keeping function. It is desirable that the time drift of this circuit be limited, typically a maximum drift of 2 min per month. Indeed, during winter periods and for private swimming pools in particular, in the event of a power failure for one reason or another, this condition may persist due to the absence of the owner of the premises (holiday home, etc.). This arrangement also makes it possible to set the time in the factory on a new device. When installing on site, the customer or the installer does not have to worry about setting the time.

In all cases, when the mains supply is restored, the device is automatically returned to normal operation. As soon as the microcontroller 70 processes a temperature measurement at the start of an operating phase of the stirring pump, the test carried out determines the choice of a new stirring program.

As long as the successively measured temperatures remain within the same range, for example between 18.1 and 21 ° C in the examples shown in the table, the microcontroller 70 maintains the same program for stirring and filtering the water. from pool 1. Pump 5 is supplied at the same predefined rates: on a daily basis of 7 hours, divided into two periods of respective duration 4 and 3 hours, in the example chosen. Otherwise, for example if the measured temperature rises to 24 ° C, a new program is selected: total duration daily brewing of 10 hours, divided into three periods of 2, 4 and 4 hours, respectively.

As previously indicated, the various operating states are displayed by the indicator lights 33 (normal operation of the pump 5) and 34 (alarm), as well as the display member 31 (measured temperature or time display) . It should be noted that if the sensor 30 must be able to detect temperature variations typically of the order of a tenth of a degree, or even less, it is not necessary for the display member 31 to display the temperature with such precision. Advantageously, a display member comprising two digital indicators with seven segments is used, which gives a sufficient indication (± 1 ° C) on the temperature of the water, which is measured with greater precision.

Apart from the automatic operating mode controlled by temperature detection, a preferred variant of implementation of the invention provides for being able to switch to a manual mode which does not have to do this regulation. The push button 32 is multifunctional and can also fulfill this function. It suffices to provide a discriminatory pressing mode (duration of manual pressing of the button greater than a predetermined threshold, for example) so that one switches to manual mode and that one forces the operation of the pump in regime continued.

Programming of the device can be done in the factory once and for all. As is known, a microcontroller is usually associated with fixed memory circuits and random access memory circuits. A fixed memory can be constituted by a ROM type memory, read only and cannot be modified, or a programmable memory of PROM, EPROM type, etc. These memories can take shape in various forms depending on how they can be programmed: data recording by electrical signals, erasure by ultraviolet light and re-recording, etc. Certain types of memories allow reprogramming on site, using specialized portable devices. In all cases, it is these memories which store the software modules and the instructions necessary for the proper functioning of the microcontroller and for the execution of specific programs.

In the case of the method of the invention as it is implemented here, information necessary for the preparation of the operating programs of the pump 5 is stored, as shown in the table above. The temperatures measured by the sensor 30 are compared with those prerecorded in memory. The usual process is to address memory locations with address words. In the application concerned by the invention, these address words are derived from the amplitude (and of the sign) of the measured temperatures. The data stored in the addressed memory positions is used to define the overall mixing times and their possible distribution into individual ranges.

In another variant embodiment, programming could be carried out by the user, entirely freely or by selection of predefined ranges. It would then be possible to enter the programming data using keys or a keyboard arranged, for example, on the control unit 3, or even using a remote control, with infrared rays for example, acting on an electro-optical sensor disposed on the front face of the housing or inside it, on the card 7.

In the latter case, it is naturally necessary to be able to open the cover of the housing 3. For all these variants, it is necessary to provide a random access memory, for example of the RAM type, that is to say random access, that you can write and read at will, or memory registers. These storage devices must be provided with an autonomous power supply, by battery or battery, to be in able to keep the programs recorded during power outages.

The foregoing description clearly explains how the invention achieves the objectives it has set for itself. It allows in particular savings in material and electrical energy by minimizing and optimizing the filtration periods. It also allows great flexibility of operation, without requiring complex measurements. Simple temperature measurements make it possible to determine the filtration times and to distribute them as well as possible on a daily basis. The components used are in common use and do not involve high costs.

In addition, the components entirely specific to the invention are few. The mounting of the device according to the invention in an existing installation does not pose any particular problems and it is easy.

It should be clear, however, that the invention is not limited to only the examples of embodiments explicitly described, in particular in relation to FIGS. 1 to 3.

In particular, the usable components and the numerical values which have been specified are in close correspondence with the specific application envisaged. Likewise, the method is not limited to daily programming, nor to a specific number of distinct tracks. Temperature measurements can be carried out at times which do not necessarily coincide with whole hours, they can even be carried out continuously.

Instead of using a microcontroller, it is also possible to use a conventional microprocessor, or even a microcomputer used elsewhere for other tasks, in particular if it is a large installation (municipal swimming pool, etc.), and generally any digital data processing apparatus with a recorded program. The alarm circuits, as has been specified, can be of various types: visual alarm, audible alarm, etc. The alarm actuation signals can have a direct effect (locally), but can also be transmitted remotely, by a remote alarm system, via a conventional telephone link for example. The system may include heating elements for the swimming pool water, actuated in response to an alarm due to a measured temperature below the minimum admissible temperature, ie 3 ° C. in the example described. The reheat command can be local or be transmitted remotely, for example by the aforementioned telephone link.

It should also be clear that the invention cannot be limited to the sole application to private swimming pools, that is to say a priori of modest dimensions and relatively little used. It finds application for other types of swimming pools or similar installations: pools of thermal centers, etc.

Claims

1. A method for maintaining the water in a swimming pool (1) by adding a disinfecting agent, characterized in that it essentially consists in automatically controlling said addition of disinfecting agent according to a detection of the temperature of said water.

2. Method according to claim 1, characterized in that said addition of disinfecting agent is carried out by treating the water in a closed circuit bypassing the swimming pool, in which the water is circulated at constant flow, by sampling and recycling in the swimming pool, during a period of operation which is subject to said temperature detection.

3. Method according to claim 2, characterized in that said circulation is carried out using a stirring pump (5) at constant flow, the operation of which is ensured according to predetermined programs, distinguished in particular by a number daily brewing sequences of the same unit duration, of which the choice is determined automatically as a function of contiguous predefined ranges of temperatures measured according to that in which the temperature determined by said temperature detection is situated.

4. Method according to claim 3, characterized in that the temperature detection is carried out periodically on said treatment circuit at the start of a brewing sequence with a time delay enabling validation of a measurement of the temperature of the water in the swimming pool determining the duration of brewing to be ensured in a given time, in particular the daily duration.

5. Method according to claim 3 or 4, characterized in that when the temperature detection reveals a measured value which is below a minimum value of risk of frost and / or above a maximum value, said pump operates continuously and an alarm is generated.

6. Method according to any one of claims 2 to 5, characterized in that said addition of disinfecting agent is carried out from a support roller, interposed on said treatment circuit, from which it is gradually released in contact with circulating water.

7. Method according to any one of claims 2 to 5, characterized in that said addition of disinfecting agent is carried out by electrolysis of the water circulating in said treatment circuit, which contains a chloride such as chloride sodium, so that electrolysis produces molecular chlorine.

8. Method according to any one of claims 2 to 7, characterized in that said stirring pump takes the water circulated in said circuit by suction partly at the bottom of the pool and partly at the surface, the two parts being mixed upstream of the temperature detection, so that the measured temperature which controls the determination of the treatment times is representative of an average temperature prevailing in the swimming pool.

9. Device for implementing the method according to any one of claims 1 to 8, characterized in that it comprises at least one pump (5) for stirring said water, sucking water from the pool for the '' recycle there after treatment in a closed circuit (60) treatment by filtration and regeneration by adding disinfecting agent bypassing the pool, and, mounted on said circuit, a sensor (30) for detecting the temperature of the circulating water, generating an electrical output signal (Vg ) representative of the measurement of said temperature, a digital data processing apparatus (70) performing comparisons between the measured temperature and predefined contiguous temperature ranges, so as to generate control signals which select an operating time of said temperature pump (5), distributed over time slots according to pre-established programs, and actuation means (75) of the pump (5) controlled by said control signals.

10. Device according to claim 9, characterized in that said digital data processing apparatus comprises, installed on a printed circuit board (7), electrical supply circuits (76), a microcontroller (70) receiving signals representing said temperature measured by said sensor (30) and provided with means for memorizing a treatment program, an electronic time base (71) for the preparation of signals corresponding to the durations and operating ranges of the stirring pump ( 5), and clock circuits (72), with permanent power supply, capable of keeping track of the time elapsed in the event of failure of said power supply circuits.

11. Device according to claim 9 or 10, characterized in that said means for actuating the pump (5) comprise an electromagnetic relay (75) supplying the pump (5) with electrical energy.

12. Device according to any one of the res- dications 9 to 11, characterized in that it comprises a control panel (3) comprising a member (31) for alternating display of said measured temperature or time, an indicator (33) for operation of said pump brewing, an alarm light (34) activated when said measured temperature is below a minimum value or above a maximum value, and a multi-functional push button (32) enabling the time to be set of said digital data processing apparatus (70) and forcing the operation of the stirring pump (5) in manual mode.

13. Device according to any one of claims 9 to 12, characterized in that it comprises means for generating a visual alarm (75, 34), sound, local or via a remote monitoring device.