FR2814792A1 - Two-way valve for circulating and stirring water in aquarium has single inlet with displaceable blade facing into water flow and pivoted at trailing edge - Google Patents

Abstract

The valve has a block of plastics material (A) with a single inlet (B) at one end and two outlets (C,D), facing in different directions. The displaceable blade has a paired obturator body (H) which may close one of the outlets at a time. An electric current may be passed through coils (K,L) on either side of the blade to move a permanent magnet (M) near the leading edge of the blade and switch it from one side to the other.

Description

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The present invention aims to describe the operation and the production of a bidirectional valve used in particular in the mixing of sea water in marine aquarium.

 The successful balance of an aquatic biotope requires mastering a large number of parameters.

 Among these parameters, the mixing of water is one of the most important, and paradoxically, it was not very long ago that it became the key to the success of the marine aquarist in particular.

notamment dans les aquariums récif aux. The necessary mixing in fresh water becomes crucial in sea water, and

especially in reef aquariums in.

 In the latter, it is normal to use successfully pumping installations capable of brewing, in 1 hour, up to 20 times the volume of the tank.

 Generally, two hydraulic circuits are necessary, one ensures the filtration and the treatment of the water, the other carries out the mixing.

 In reality, a stirring pump is always insufficient and one must use two, even three or four, pumps if the tank is large, to be sure not to create preferential currents and dead zones in the aquarium.

 These dead zones see the accumulation of organic debris which quickly becomes sources of pollution in nitrates and phosphates destroying the balance of the tank.

 The various brewing pumps are put into service alternately by means of programmers, and some can be fitted with adjustable nozzles to distribute the water streams in the best possible decor.

 Such installations are expensive, noisy and unsightly, because these pumps are submerged near the surface to be easily oriented, maintained and cleaned. In addition, an aggravating circumstance, they heat the water in the tank, forcing the use of a cold group to maintain a suitable temperature in summer, another parameter which is also critical.

 The financial aspect is not negligible in this type of relatively expensive installation, and the use of several efficient pumps in brewing, weighs on the total cost of the system as well as on its maintenance.

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 The object of the present invention is to do away with internal pumps while ensuring excellent mixing without noise or overheating.

 The following description refers to the appended drawings which represent, without any limiting nature, an exemplary embodiment of the proposed system and of the parts thereof.

 The system consists of a valve with several outlets which, taking water from an outside pump, allows it to be distributed in different directions.

 The valve is designed to operate both outside the tank, in the gallery or immersed in the tank itself.

 Its small size allows it to be easily concealed and its heating is zero.

 Figure 1 shows a longitudinal section of the main body of this valve, and its components.

 Figure 2 shows a longitudinal and lateral section of the valve plug.

 Figure 3 is a section of the valve body showing the flow of water and its distribution around the shutter.

 FIG. 4 shows in a nonlimiting manner the block diagram of a system of random commands.

 In Figure 1, and in its simplest form, it consists of a rectangular plastic body A, which receives water at one end B, and allows its routing to two outputs in Y, C and D.

 In a nonlimiting example, a flow rate of 4000 liters per hour can easily use 20 millimeter circulation orifices.

 These two outlets open into a cavity of inverted triangular shape F surmounted by a rectangular shape E. The apex of the inverted triangle has a cylindrical cavity G which will serve as an axis for a central shutter having an axis of rotation N.

 The angle generated by the two outlets is designed so that one outlet is obstructed by the shutter, the other receives the water with a pressure drop as close as possible to that of a straight tube of identical section.

 On either side of the rectangular part, two cavities K and L will make it possible to receive an actuator which will be described later.

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 In the center of the valve body, and centered in the cylindrical cavity G, a movable shutter H will make it possible to select one or the other of the two outlet orifices.

 For this, the slopes 1 and J of the lower faces of the valve H must be identical to those of the inverted triangle of the valve body.

The tightness produced by the plating of the shutter being important, it is necessary to make slight striations on the outlet seats, in order to avoid a complete stop of circulation. A complete stop is to be avoided in a seawater application, to avoid rapid fouling of the piping.

 2 shows a section of the movable shutter, the cylindrical base N of which is embedded in the housing G of the main body.

 This embedding generates an axis of rotation which allows the two faces of the shutter to alternately obstruct the two outputs C and D.

 At the top of the shutter a rare earth magnet M is permanently embedded. The choice of a rare earth magnet is important to obtain a high density of magnetic fields for a reduced weight. In addition, the magnet being requested by the actuator in pole reversal, only the rare earths support this type of operation without altering the magnetic properties.

 The slopes of the warhead from the top of the shutter are perfectly symmetrical, and according to the invention play an important role in the functioning of the system.

 The inversion of the shutter uses two electromagnets arranged in the cavities K and L, while the upper part of the pallet H houses the rare earth magnet M shown in FIG. 2, and whose surfaces are opposite the magnetic cores of the coils.

 The purpose of this magnet is only to polarize the shutter H to allow the two electromagnets K and L to work in opposition on the magnet M, one pulling, the other pushing.

 This provision should, in theory, be sufficient to make the whole work, but the reality is different.

 When it is proposed to pass a flow through a pipe, there is creation of a pressure drop and therefore of a pressure which, in our case, will be exerted on one of the faces of the shutter by opposing its tilting.

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 This force would lead to the use of powerful, heavy, costly and above all energy-consuming coils with the risk of heating.

 To avoid this major drawback, and in the context of the invention, it has been imagined to profile symmetrically the end of the shutter which receives the stream of water sent by the pump. n is then subjected to two forces, one due to the pressure drop which tends to press it against the wall, the other which, by reaction on its other face, tends to move it away from the wall. According to the invention, the result of these two forces must be as weak as possible. Figure 3 shows the distribution of CE water currents on the shutter.

 A metastable system is thus produced which allows the shutter to oscillate continuously at random from the modulation of the pump output currents.

 To stabilize the system, it suffices to present a magnetic mass in front of the pallet H. The core of the coils K and L plays this role perfectly and blocks the valve in a stable position.

 The tilting is then carried out by simple cancellation of the magnet field using a very small electric pulse in the coils.

 In fact, the valve is never supplied, except during the few thousandths of a second of the command, and the energy consumption of its tilting is supplied hydraulically by the circulation pump.

 The two coils can be excited separately, in parallel or in series, by pulses with respect for the polarities with respect to the magnet of the shutter. The latter can switch by excitation of a single coil or push-pull by excitation of both.

 The energy of the control is very low to the point that the valve can be powered by battery allowing to remove the always dangerous mains supply in seawater tanks.

 On commissioning, there is always a dissymmetry in the control energies of the two coils. This asymmetry comes essentially from the flow regime of the water, which is always very turbulent at the outlet of a pump.

 If it is desired to obtain identical energy consumption on the two coils, it is preferable to attack the valve in laminar flow.

At the same time, this condition ensures the lowest energy consumption.

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 The balance of a marine biotope is all the better as the reproduction of natural conditions is possible. It is clear that despite a lot of effort and imagination, it is difficult in a tank of a few hundred liters to reproduce nature, but certain parameters can be of great importance.

 The great variety of rhythms in nature is one of the difficulties that the aquarist should take into account. Except for obvious reasons most of the operations of maintenance and management of an aquarium are scheduled, that is to say occur at fixed times or at fixed time intervals.

 Nature does not do this, and the movement of waves and surf on a coral reef is anything but regular. Basically, it should not be forgotten that this permanent agitation is the engine of the food and the metabolism of aquatic organisms.

 The study of these rhythms shows that they are not the result of a chance, but that they obey periodicities which generally depend on the considered sites. A surf which will play an important role in the balance of a reef ecosystem, will have a periodicity, determined by the seabed for example.

 The ease with which this valve can be inverted allows a totally random command without any risk of deterioration even if two commands follow each other in less than a second.

 This condition cannot be achieved with an electric motor for which most of the wear comes from starting.

 Still within the framework of the invention, we have produced a periodic random generator, based on the sliding of frequencies of three independent oscillators.

 Chance comes from the probability that during frequency shifts three pieces of information overlap, but the periodicity is fatal since each oscillator is stable.

 Figure 4 shows a very simple system which consists of three oscillators X, Y, and Z, of which Z is made variable by a potentiometer allowing to modify the range of random frequencies. These three shaped oscillators mix in logic gates Wl, W2.

The outgoing signals enter a frequency divider W3, then are again shaped in time and amplitude in W4 to attack

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les blocs de commande des bobines W6 et W7 par l'intermédiaire d'une bascule D, W5qui inverse et sélectionne les polarités.

the control blocks of the coils W6 and W7 via a flip-flop D, W5 which reverses and selects the polarities.

 Note that it is desirable in WS to prohibit the possibility of two simultaneous commands which without being harmful to the valve would modify its cycle.

 The simple variation of the potentiometer of oscillator Z modifies the frequency of the chance of the commands allowing, for example, to differentiate particular periods of the day or the night.

 By this method, and within the framework of the invention, it is possible to reproduce with fidelity the pseudo-random behavior of sea currents without any alteration of the operation of the valve, and this even if to simulate a storm one imposes a control rhythm of the order of a second.

 Of course, without departing from the scope of the invention, the various components of the valve which have just been described, by way of example, may be replaced by equivalent elements fulfilling the same functions.

Claims (8)

1) Bidirectional valve, operating by the angular displacement of a movable shutter H, characterized in that the position of this shutter is made unstable by its bevelled size in the liquid stream.  2) Valve according to claim 1 characterized in that this shutter H, is polarized by the establishment of a magnet M, and made stable by the presence of the permeable cores of two coils K and L, external to the valve body .  3) Valve according to claims 1 and 2, characterized by a control using the coils K and L arranged around the permeable cores, and canceling the magnetic field of the magnet M, thus causing the shutter to tilt H.  4) Valve according to claim 3, characterized in that the electrical control is very low, the hydraulic energy being the engine of the tilting.  5) Valve according to claim 1, characterized in that the tilting shutter has an upper profile in the form of a symmetrical parabola, orienting the water streams so as to equalize the hydraulic pressures on either side of the shutter .  6) Valve according to claim 3 characterized in that the stable position is obtained in the absence of external energy, allowing to remain positioned without any heating.  7) Valve according to all the preceding claims, characterized by a very fast operation of the shutter H, allowing a high operating speed without any mechanical wear, and allowing to be controlled by a random generator.  8) Valve according to all of the preceding claims, characterized by silent operation.