Fluidic control device and magnetocaloric machine comprising said fluidic control device

Abstract

The invention relates to a fluidic control device (10), particularly for a magnetocaloric machine, comprising at least one fluidic distributor (11), having a first conduit (C1) connected to a first circuit segment (5a), and a second conduit (C2) connected to a second circuit segment (5b), said conduits being separate. The fluidic distributor comprises a body (12), and a shutter (13) movable relative to said body between two switching positions to alternately conduct said first conduit (C1) and said second conduit (C2). The body and the shutter each have a supply orifice (OA1, OA2) corresponding to the first conduit (C1) and a return orifice (AR1, OR2) corresponding to the second conduit (C2).The device further comprises an eccentric control mechanism (20) coupled on one side to a rotary actuator (4) and on the other side to the shutter (13) for moving it from one switching position to the other in a continuous outward movement. Figure for the abbreviation: Fig 3A.

Description

Title of the invention: Fluidic control device and magnetocaloric machine comprising said fluidic control device. Technical field

[0001] The present invention relates to a fluidic control device in general and more particularly intended to equip a magnetocaloric machine, comprising at least one fluidic distributor having at least one first conduit arranged to be connected to a first portion of the circuit and a second conduit arranged to be connected to a second portion of the circuit, said first conduit and said second conduit being separate, said fluidic distributor having a body and a shutter movable relative to said body between at least two switching positions to make said first conduit and said second conduit alternately conduct, said body and said shutter each having at least one supply orifice corresponding to the first conduit and at least one return orifice corresponding to the second conduit.

[0002] The invention also relates to a magnetocaloric machine comprising at least one fluidic distributor connected to a fluidic circuit, a magnetic arrangement, a set of active elements based on magnetocaloric material, said magnetic arrangement and said set of active elements being arranged to be mobile relative to each other to create an alternation of magnetic cycles according to a defined frequency, and a heat transfer fluid arranged to circulate in said fluidic circuit through said active elements. Previous technique

[0003] Current magnetocaloric (MC) machines have hydraulic distributions made from repurposed elements, such as commercially available distributors designed for gas or oil, industrial solenoid valves, custom-made distributors not integrated into the machine design, experimental hydraulic distribution devices not optimized for industrial integration.

[0004] Commercially available diverted valves designed for gas or oil have a reduced number of cycles and produce a significant pressure drop. The lifespan of these components is insufficient considering the number of cycles performed by an MC machine over its lifetime. When diverted valves are shared by groups of synchronous active magnetic regenerative (AMR) elements, they require a large quantity of piping, which complicates industrial integration and makes mass production impractical. Their internal design is not controlled, and consequently, the flow cross-sections depending on the stroke are poorly known, especially since they are not made to operate in intermediate positions halfway between the intended common extreme switching positions.

[0005] Industrial solenoid valves are inefficient in terms of energy consumption and also have a limited lifespan. Custom-made valves have a suitable footprint for prototypes but are difficult to integrate with magnetocaloric technology. They are actuated by cams, which are a source of noise and mechanical friction. Fluidic valves of all types have discontinuous movement and therefore require inertial force to be set in motion. Conventional cam profiles do not allow for the recovery of kinetic energy from moving valves during deceleration. The discontinuous movement of cam-driven valves generates shocks and, consequently, noise and energy loss. In general, the use of unsuitable valves poses problems with lifespan and leakage between circuits and with the external environment. Description of the invention

[0006] The present invention aims to overcome these drawbacks by proposing a fluidic control device specially designed and adapted to the needs of an MC machine, which is compact, and which can be integrated into the machine's footprint, positioned as close as possible to the AMRs to reduce or even eliminate piping and fluidic losses, can be shared to simplify the internal fluid circuits of the machine, is easily industrialized, is driven by a continuous movement, is silent, produces little loss by friction or shock and therefore consumes little energy.

[0007] The invention also aims to provide a fluidic control device whose internal design is perfectly controlled, the passage sections being able to be determined as a function of the stroke of the shutter relative to the body in order to minimize the transient phases between the extreme switching positions (open / closed).

[0008] The object of the invention is achieved by a fluidic control device as defined in the preamble, characterized in that it further comprises an eccentric control mechanism, movable relative to the body of said at least one hydraulic distributor, said control mechanism being coupled on the one hand to a rotary actuator and on the other hand to said obturator to move it relative to said body in a continuous outward movement, from a continuous inward movement of said rotary actuator. This arrangement has the advantage of moving the obturators in a continuous, uninterrupted, and jerk-free movement, silently, and with low energy consumption. energy, preserving the integrity of moving parts to guarantee a lifespan compatible in particular with that of magnetocaloric machines.

[0009] In a preferred embodiment of the invention, said control mechanism comprises a drive element integral with said rotary actuator, said drive element having a shape of revolution with a geometric center distinct from the center of rotation of said actuator, and a transmission element assembled to said drive element by a pivot joint to be movable in circular translation, said transmission element being coupled to said shutter. This arrangement has the advantage of ensuring control of the fluid distribution synchronized with the magnetic cycles within an MC machine by means of a simple, inexpensive, reliable, durable, and maintenance-free mechanism.

[0010] In a first embodiment of the invention, said shutter is mobile in rotation about an axis of rotation and includes a coupling tip eccentric with respect to said axis of rotation of the shutter, said transmission plate having a circular housing housing said eccentric coupling tip by a pivot link.

[0011] In a second embodiment of the invention, said shutter is a double-acting shutter which is movable in translation along a translation axis and includes a follower finger, said transmission plate having a groove housing said follower finger by a sliding link.

[0012] In a third embodiment of the invention, said shutter is a single-acting shutter which is movable in translation along an axis of translation and includes a follower member maintained in contact with the transmission part by a deformable part.

[0013] In the first variant, said first conduit and said second conduit are at least partly coaxial and parallel to the axis of rotation of the shutter. And in the second and third variants, said first conduit and said second conduit each pass through said body transversely to the axis of translation of the shutter.

[0014] The opening widths between the supply ports and the return ports, respectively, may not be identical, in order to generate short transition times between the opening and closing of said first conduit and said second conduit, respectively. Preferably, the supply and return ports of one of the parts of said body or said oblong are formed by a narrow oblong opening or by a slot, and the supply and return ports of the other part of said body or said oblong are formed by an opening wider than said narrow opening. This arrangement has the advantage of avoiding the presence of dead volumes and the phenomenon of passive thermo-fluidic regeneration resulting from the flow of a heat transfer fluid at two different temperature levels in the same conduit or in the same volume of the distributor, which has the effect of fluidly isolating the AMRs from the thermal sources.

[0015] The fluidic control device advantageously comprises N fluidic distributors arranged in a circle at equal distances from an axis of rotation of said rotary actuator, the shutters of said distributors being controlled by said eccentric control mechanism. This arrangement has the advantage of centralizing and synchronizing the control of said shutters.

[0016] The object of the invention is also achieved by a magnetocaloric machine as defined in the preamble, characterized in that it comprises at least one fluidic control device described above, comprising at least one fluidic distributor per active element, in fluidic contact with a first end of said active element, and in that said fluidic distributor is arranged to circulate said heat transfer fluid through said active element, alternately in a first direction of circulation in a first portion of the circuit and in a second direction of circulation, reversed with respect to the first direction of circulation, in a second portion of the circuit of said fluidic circuit, according to a switching frequency between said at least two switching positions of said fluidic distributor which is a multiple of the frequency of the magnetic cycles.

[0017] This arrangement has the advantage of separating the heat transfer fluid distribution for each AMR (Automatic Magnetic Resonance) unit, by separating the direction of fluid flow for each AMR into dedicated conduits for each direction of flow, at every point in the system outside the AMR, between the control units and the AMRs on the one hand, and between the control units and the heat sources on the other. It guarantees a low leakage rate between conduits with opposite directions of flow, between the conduits and the AMR, as well as between the conduits and / or the AMR and the external environment. Furthermore, it is easily configurable, even controllable, in terms of phase shift relative to the magnetic field and opening time, so as to modulate the evolution of the fluid velocity relative to the evolution of the magnetic field applied to the AMR and thus vary the operating point of the AMRs.

[0018] Said eccentric control mechanism is preferably coupled to a rotary actuator coupled to said magnetic arrangement or said set of active elements. This arrangement has the advantage of synchronizing the fluid distribution with the magnetic cycles of the MC machine by means of a simple, inexpensive, reliable, durable and maintenance-free mechanism.

[0019] The number of supply and return ports provided respectively in the body or in the obturator of said at least one fluidic distributor may be equal to the number of magnetic poles of said magnetic arrangement, the switching frequency between the two switching positions of said fluidic distributor being in this case equal at the frequency of the magnetic cycles generated by said magnetic arrangement. This arrangement allows the full exploitation of the magnetic cycles.

[0020] In a preferred embodiment of the invention, said fluidic control device comprises two fluidic distributors per active element, in fluidic contact with a first end and a second end of said active element. This arrangement has the advantage of balancing the circulation of the heat transfer fluid, ensuring homogeneity of fluid flow rates between the active elements, and ensuring optimal reciprocating fluid movement in each active element.

[0021] In this case, the fluidic control device advantageously comprises two control mechanisms arranged on either side of the set of active elements to control the two fluidic distributors per active element, and the two control mechanisms being coupled to the rotary actuator, with or without a means of phase-shifting one relative to the other. This arrangement makes it possible to balance the forces required for control, while allowing the introduction of a configurable, or even automatable, phase shift and / or opening time of the alternating flow of the fluid with respect to the applied magnetic field to achieve an optimal AMRR (Active Magnetic Regenerative Refrigeration) cycle from an imperfect magnetic field evolution.

[0022] Preferably, the opening amplitude of the forward and return orifices of one of the parts of said body or said obturator corresponds substantially to the amplitude of a magnetic pole of said magnetic arrangement. This arrangement offers the possibility of a square-wave velocity evolution, in accordance with the requirements of a Brayton or near-Ericsson magnetocaloric cycle in AMRR.

[0023] The fluidic control device advantageously comprises N fluidic distributors or pairs of fluidic distributors, N being equal to the number of active elements of said assembly, arranged in a circle equidistant from an axis of rotation of said rotary actuator, and controlled by said control mechanism(s). This arrangement has the advantage of separating the distribution of the heat transfer fluid for each AMR and of allowing the sharing of the fluid channels exiting the distribution system between the MC machine and the heat sources, while simplifying the internal fluid circuits of the machine. It also allows the fluidic control to be synchronized with the evolution of the magnetic field, which varies out of phase for each AMR. Brief description of the drawings

[0024] The present invention and its advantages will become more apparent from the following description of several embodiments given by way of non-limiting examples, with reference to the accompanying drawings, in which:

[0025] [Fig-1] [Fig. 1] is a schematic diagram of an MC machine equipped with a fluidic control device according to a particular mode of the invention,

[0026] [Fig.2] [Fig.2] is a diagram of the fluidic circuit of an MC machine equipped with a fluidic control device according to a particular mode of the invention,

[0027] [Fig.3A] [Fig.3A] is an axial cross-sectional view of a rotary fluidic distributor according to a first embodiment of the invention in a first switching position,

[0028] [Fig.3B] [Fig.3B] is a radial cross-sectional view of the fluidic distributor of [Fig.3A] along the section plane III-III,

[0029] [Fig.4A] [Fig.4A] is an axial cross-sectional view of the fluidic distributor of [Fig.3A] in a second switching position,

[0030] [Fig.4B] [Fig.4B] is a radial cross-sectional view of the fluidic distributor of [Fig.4A] along the section plane IV-IV,

[0031] [Fig.5] [Fig.5] is a perspective view of the body of the fluidic distributor of figures 3A and 4A,

[0032] [Fig.6] [Fig.6] is a perspective view of the movable obturator of the fluidic distributor of Figures 3A and 4A,

[0033] [Fig.7] [Fig.7] is a plan view of a fluidic control device equipped with rotary fluidic distributors according to Figures 3A and 4A and an eccentric control mechanism for the movable shutters,

[0034] [Fig.8] [Fig.8] is a plan view similar to [Fig.7], showing the eccentric control principle of the movable shutters,

[0035] [Fig.9] [Fig.9] is an axial cross-sectional view of the fluidic distributor of [Fig.3A] integrated into a partially represented MC machine,

[0036] [Fig. 10] [Fig. 10] is a perspective view of an MC machine equipped with a fluidic control device according to a preferred mode of the invention,

[0037] [Fig. 11] [Fig. 11] is a plan view of a fluidic control device according to a second embodiment of the invention, equipped with linear fluidic distributors and an eccentric control mechanism for the movable shutters,

[0038] [Fig. 12] [Fig. 12] is an axial cross-sectional view of the device of [Fig. 11], in a first switching position,

[0039] [Fig.13] [Fig.13] is an axial cross-sectional view similar to that of [Fig.12], in a second switching position, and

[0040] [Fig. 14] [Fig. 14] is an axial cross-sectional view of the device of [Fig. 11] according to an alternative embodiment of the eccentric control mechanism. Description of the implementation methods

[0041] In the illustrated embodiments, identical elements or parts bear the same reference numbers. Furthermore, terms with a relative meaning, such as vertical, horizontal, right, left, front, back, above, below, etc., should be interpreted under normal conditions of use of the invention, as shown in the figures. The X, Y, and Z axes are defined by an orthonormal coordinate system illustrated in [Fig. 1]. Moreover, the geometric positions indicated in the description and claims, such as "perpendicular," "parallel," and "symmetrical," are not limited to the strict sense defined in geometry, but extend to geometric positions that are close, that is, that allow a certain tolerance within the technical field considered, without affecting the result obtained.This tolerance is notably introduced by the adverb "sensible", without this term necessarily being repeated before each adjective.

[0042] With reference to the figures, the fluidic control device 10, 30 according to the invention is of primary interest to magnetocaloric machines 1, hereafter referred to as machine MC 1, for the reasons set out above, but extends to any other technical field in which it is necessary to switch a fluidic circuit according to a determined frequency to circulate a fluid alternately in two opposite directions, without mixing the going fluid and the returning fluid.

[0043] In MC 1 machines, the direction of movement of a heat transfer fluid as a function of the magnetic cycles undergone by AMRs depending on whether they are in or out of a magnetic field makes it possible to perform a heat pumping function from magnetic work, or to recover magnetic, and therefore mechanical, work from a temperature differential. The present invention thus applies to MC heat pumps and thermomagnetic motors, an example of which is described in the applicant's publication WO2021 / 255040. The principle of active regeneration in a porous matrix (AMR) can be extended to all heat devices, such as electro-caloric (EC), barocaloric, elastocaloric (eC), etc. devices, without limitation of the vector used to adiabatically vary the temperature or isothermally vary the entropy of the active matrix.

[0044] Figure 1 schematically illustrates the operation of a machine MC 1, described succinctly, since it is not the subject of the invention as such. The following description refers to a machine MC 1 operating as a heat pump. In the example shown, it comprises a fixed assembly in the form of a stator S provided with a set of active elements 2 based on magnetocaloric material, hereinafter referred to as AMR 2, and a moving assembly in the form of a rotor R provided with a magnetic arrangement forming magnetic poles 3. The rotor R is driven in rotation about an axis A, parallel to the X-axis of the frame of reference. orthonormal, by a motor 4 to subject the AMR 2s to a variation in magnetic field and generate within said AMR 2s a temperature variation in the vicinity of their Curie temperature. Of course, the inverse configuration exists in which the set of AMR 2s is supported by a rotor R and the magnetic arrangement 3 by a stator S, but this configuration complicates the connection of the AMR 2s to the fluidic circuit.

[0045] In [Fig. 1], and solely for the purpose of explaining the operation of the MC 1 machine, only two AMR 2 and one magnetic pole 3 are shown. The MC 1 machine includes an internal fluid circuit 5 in which a heat transfer fluid circulates via a pump 6 through said AMR 2 and heat exchangers E1 and E2, enabling the AMR 2 to exchange heat with external devices D1, D2. Depending on the application, the heat transfer fluid may be liquid or gaseous. The fluid circuit 5 may also include a buffer tank 7 of heat transfer fluid to compensate for any heat transfer fluid losses and / or variations in the volume of the heat transfer fluid as a function of temperature and / or pressure.

[0046] The fluidic circuit 5 comprises two circuit portions 5a and 5b, namely a first circuit portion 5a and a second circuit portion 5b, coupled respectively to a heat exchanger El, called hot exchanger El and a heat exchanger E2, called cold exchanger E2. The two circuit portions 5a, 5b are connected by a fluidic control device 10, 30 arranged to connect in series the AMR 2 to the heat exchangers El, E2 alternately in one and the other circuit portions 5a, 5b and create an alternation of thermal cycles at a determined frequency, synchronized with the alternation of the magnetocaloric cycles induced by the rotation of the rotor R.

[0047] In the example shown, the fluid control device 10, 30 comprises, for each AMR 2, two fluid distributors 11, 31 arranged on either side of the AMR 2, and more precisely, attached to the ends of the AMR to be in direct fluid contact with the AMR without any intermediate fitting or pipe. The fluid control device 10, 30 is designed to impose a single direction of flow of the heat transfer fluid in the circuit portions 5a, 5b and in the heat exchangers E1, E2, illustrated by the arrows F. In an embodiment not shown, the fluid control device 10, 30 may comprise, for each AMR 2, only one fluid distributor 11, 31 arranged on only one side of the AMR 2.In this case, the opposite side of the AMR 2 has control devices for the direction of flow of the heat transfer fluid in the circuit portions 5a, 5b to impose the single direction of flow of the heat transfer fluid in the heat exchangers El, E2. .

[0048] With reference to [Fig. 1], the operation of machine 1 is briefly described. In a first thermal cycle, the fluidic distributors 11 are in a The first switching position, as illustrated in [Fig. 1], and the heat transfer fluid circulates in a first portion of the circuit 5a, represented by a solid line in a clockwise direction. It passes through the AMR 2 located at the bottom of [Fig. 1], which undergoes a heating cycle as it is situated in the magnetic field of one of the magnetic poles 3 of the rotor R, passes through the hot exchanger E1 where it transfers the collected heat to an external device D1, then passes through the AMR 2 located at the top of [Fig. 1], which undergoes a cooling cycle as it is situated outside the magnetic field, and passes through the cold exchanger E2 where it transfers the collected cold to an external device D2.

[0049] In a second thermal cycle, the fluid distributors 11 are in a second switching position, not shown in [Fig. 1], and the heat transfer fluid circulates in a second circuit portion 5b, which is represented, outside the heat exchangers E1 and E2, the pump 6 and the reservoir 7, by short dashed lines in a counterclockwise direction. It passes through the AMR 2 located at the bottom of [Fig. 1], which is now undergoing a cooling cycle as it is located outside the magnetic field (not shown), passes through the cold heat exchanger E2 where it transfers the collected cold to an external device D2, then passes through the AMR 2 located at the top of [Fig. 1], which is now undergoing a heating cycle as it is located in the magnetic field of one of the magnetic poles 3 of the rotor R, and passes through the hot heat exchanger E1 where it transfers the collected heat to an external device D1.

[0050] The first and second thermal cycles are repeated according to a switching frequency determined by the fluidic control device 10, 30, which includes a control mechanism 20 for the fluidic distributors 11, 31. The control mechanism 20 can be coupled to the motor 4, or to a dedicated actuator (not shown). If it is coupled to a dedicated actuator, then a control unit (not shown) is provided to synchronize the operation of the dedicated actuator with the motor 4 of the rotor R, particularly in the case of a magnetic refrigeration generator.

[0051] Figure 2 schematically illustrates a portion of the fluidic circuit 5 of the MC 1 machine equipped with the fluidic control device 10, 30 of the invention. In this example, the MC 1 machine is viewed from one of its ends, in the YZ plane, the axis of rotation A of the rotor R being perpendicular to said plane. The rotor R has two diametrically opposed magnetic poles 3, each extending over approximately a quarter circle. Eight AMRs 2 are distributed regularly around the axis A, of which four AMRs 2 are located in the magnetic field of the magnetic poles 3, and four AMRs 2 are located outside the magnetic field of the magnetic poles 3.The fluidic circuit 5 is illustrated by a large circle corresponding to the first portion of circuit 5a in which the heat transfer fluid circulates from the reservoir 7 and the pump 6, through the cold exchanger E2, towards the AMR 2 under magnetic field, via a first of the fluidic distributors 11, and by a small circle concentric to the large circle. always corresponding to the first portion of circuit 5a in which the heat transfer fluid circulates from the other AMR 2, which are not exposed to the magnetic field, via a second of the fluid distributors 11, towards the reservoir 7.

[0052] Fig. 2 also shows the control mechanism 20 of the fluidic control device 10, 30 schematically represented by an eccentric central piece coupled to the axis A in which are housed coupling tips 21 linked to the fluidic distributors 11, 31 to generate their movement from one switching position to another in a synchronous manner with the variation of the magnetic cycles.

[0053] With particular reference to a first embodiment of the invention shown in Figures 3A to 9, the fluid distributors 11 are rotary distributors positioned axially in the machine MC 1, parallel to the axis A. Each comprises a tubular body 12 with axis B parallel to the axis A, mounted optionally in the stator S, and a shutter 13 in the form of a movable plug rotating relative to the body 12 along the axis B, between at least two switching positions. In the example shown, the shutter 13 passes completely through the body 12 and has a first end in direct communication with an AMR 2, and a second end, provided with the coupling tip 21. This coupling tip 21 has a shape of revolution whose geometric center C is eccentric with respect to the axis of rotation B of the shutter 13.

[0054] The fluidic distributor 11 comprises a first conduit Cl and a second conduit C2 fluidically separated from each other. It is particularly designed to alternately conduct the first conduit Cl and the second conduit C2 according to a predetermined switching frequency synchronized with the magnetic cycles undergone by the AMR 2.

[0055] The first conduit Cl is arranged to be connected to the first section of circuit 5a in a first switching position of the distributor illustrated in Figures 3A and 3B, in which the heat transfer fluid enters the AMR 2 (supply circuit). The body 12 and the obturator 13 each have a supply orifice OA1, OA2 opposite each other. The first conduit Cl has the supply orifice OA1 of the body 12 which communicates directly with the first section of circuit 5a and with the supply orifice OA2 of the obturator 13, which preferably opens into an annular channel 14 which communicates via an intermediate perforated zone 15 into a central channel 16, which communicates directly with the AMR 2 at a first end.

[0056] The second conduit C2 is arranged to be connected to the second circuit portion 5b in a second switching position of the distributor illustrated in Figures 4A and 4B, in which the heat transfer fluid exits the AMR 2 (return circuit) from its first end. The body 12 and the obturator 13 each have a corresponding return orifice OR1, OR2. The second conduit C2 preferably has a peripheral channel 17 arranged around the central channel 16, which communicates directly with the AMR 2 at its first end, and with the return port OR2 of the obturator 13, which opens into the return port OR1 of the body 12, which communicates directly with the second portion of the circuit 5b.

[0057] Figure 5 illustrates the body 12 of the fluid distributor 11, showing the relative arrangement between the supply port OA1 and the return port OR1, as well as the shape of the opening of these ports. Axially, they are offset by a distance d corresponding to the distance between the supply ports OA2 and the return port OR2 of the obturator 13. Radially, they are offset by an angle defined by the center distance between a magnetic zone and a non-magnetic zone. The supply ports OA1 and OR1 have an enlarged opening that extends radially from the axis of rotation B of the obturator 13 at an angle α, illustrated in Figures 3B and 4B, determined by the magnetic zone corresponding to the angular extent of the magnetic pole 3 on the one hand, and by the non-magnetic zone corresponding to the angular extent between two consecutive magnetic poles 3 on the other.In this case, the angle α is approximately equal to 90°, corresponding to the extent of a magnetic pole 3, which is relevant for a machine having two diametrically opposed magnetic poles 3. The opening of the supply orifices OA1 and return orifices OR1 extends over an axial length L, preferably corresponding to the length of the supply orifices OA2 and return orifices OR2 of the obturator 13. The supply orifices OA1 and return orifices OR1 of the body 12 of the distributor 11 preferably have an identical cross-section. Each supply orifice OA1 and OR1 has, in this example, a rectangular opening inclined radially in the body 12. This shape is only a non-limiting example and can vary according to the desired velocity profiles for the heat transfer fluid, as explained later.

[0058] Figure 6 illustrates the obturator 13 of the fluidic distributor 11, showing the relative arrangement between the supply port OA2 and the return port OR2. Axially, they are offset by a distance d. Radially, they are aligned on a generatrix of the obturator 13. The supply ports OA2 and return ports OR2 preferably have a narrow, oblong opening, extending axially over a length L corresponding to the length of the supply ports OA1 and return ports OR1 of the body 12. The supply ports OA2 and return ports OR2 of the obturator 13 of the distributor 11 preferably have an identical cross-section, determined to be equal to the cross-section through an AMR 2, in order to avoid pressure losses.

[0059] The number of pairs of a forward orifice OA2 and a return orifice OR2 is a function of the number of magnetic poles 3 of the machine MC 1. In the illustrated example, the shutter 13 has two pairs of a forward orifice OA2 and a return orifice OR2 which are aligned respectively on two diametrically opposed generatrices of the shutter 13, and the machine MC 1 has two magnetic poles 3 diametrically opposed. In this configuration, the rotation frequency of the shutter 13 is equal to the rotation frequency of the magnetic arrangement.

[0060] The amplitude and shape of the opening of the supply orifices OA1, OA2 and the return orifices OR1, OR2 are determined in order to maximize the use of the heat transfer fluid which circulates through the AMR 2 during the entire duration of each magnetic cycle, given that the amplitude of the opening corresponds to the amplitude of a magnetic pole 3. It also makes it possible to drastically reduce the duration of the transient phases between two consecutive magnetic cycles thanks in particular to the oblong shape of the supply orifices OA2 and return orifices OR2 of the shutter 13 which generates very short opening and closing times of the fluidic circuit.

[0061] During the transient phases of the magnetic cycles corresponding to positions where the magnetic field generated by the magnetic poles 3 is highly non-uniform, the restriction and cessation of the heat transfer fluid circulation are achieved when the enlarged orifices of at least one of the fluid distributors 10 at at least one end of the AMR 2 do not open onto one of the narrow orifices of said distributor. The shape of the enlarged orifices—circular arc, triangle, rectangle, etc.—allows for progressive restrictions in the fluid passages upon closure, slowing the heat transfer fluid before stopping and gradually restoring its circulation upon opening. This prevents water hammer and ensures a fluid velocity evolution that is favorable and in phase with the evolution of the applied magnetic field during the magnetic transient phases.A square shape at the ends of narrow and / or widened orifices allows for an abrupt closure of the fluid passage section.

[0062] Figures 7 and 8 illustrate the control mechanism 20 of a fluidic control device 11 arranged to control the synchronous movement of the obturators 13 of a number N of fluidic distributors 11. In the illustrated example, the fluidic control device 11 comprises sixteen fluidic distributors 11, arranged in a circle around the axis A of the machine MC 1 and regularly distributed, in which each fluidic distributor 11 corresponds to an AMR 2. The control mechanism 20 is eccentric.

[0063] The control mechanism 20 comprises a drive part 22 having a shape of revolution, such as an annular plate, having a geometric center D distinct from the center of rotation of the motor 4 corresponding to the axis A. The drive part 22 is fitted onto a shaft 8 of the motor 4 to be driven in a continuous eccentric rotational movement by said motor. It also comprises a transmission part 23 having a shape of revolution, such as an annular plate, having a geometric center coinciding with the center D. The transmission part 23 is assembled to the drive part 22 by a pivot joint to be driven in a circular translational movement. The transmission piece 23 preferably includes a number N of circular housings 24 arranged in a circle around the axis A and regularly spaced, each circular housing 24 being assembled to a coupling end 21 of one of the shutters 13 by a pivot joint. Thus, the continuous rotation of the motor 4 of the magnetic arrangement preferably drives the continuous rotation in the same direction and synchronously of the shutters 13 of all the distributors 11, with a phase shift from one to the other determined by their angular arrangement with respect to the magnetic poles 3.

[0064] Fig. 8 represents the fictitious deformable parallelogram which allows the transmission of the rotational motion of the motor 4 to a rotational motion of the shutter 13 via a circular translational motion of the transmission part 23. The parallelogram has two fixed points, namely the rotation axes A of the motor 4 and B of the shutter 13, and is deformed by the continuous rotation of the two moving points, namely the geometric center D of the driving part 22 and of the transmission part, and the geometric center C of the coupling tip 21, around the two fixed points A and B respectively.

[0065] Figure 9 illustrates an example of integrating a fluid distributor 11 into the stator S of a machine MC 1, opposite an AMR 2. In the right-hand part of the figure, the AMR 2 is mounted in a specific support 9, which is fixed and forms part of the stator S. The fluid distributor 11 is mounted in one of the parts SI of the stator S, in direct contact with the support 9 of the AMR. The obturator 13 of the fluid distributor 11 extends through the support 9 to the corresponding end of the AMR 2. Fluid sealing between the various parts of the distributor, the stator part S1, and the support 9 is ensured by sealing elements OE. In the left-hand part of the figure, the coupling end 21 is mounted in a circular housing 24 of the transmission part 23.The supply ports OA1, OA2 of the fluidic distributor 11 communicate with the first section of the circuit 5a, visible in this figure, which is formed by channels directly drilled into the stator part SI. This arrangement eliminates the need for piping and corresponding fittings.

[0066] Figure 10 shows an example of an MC 1 machine assembled as a compact module, ready for installation in a thermal system. The MC 1 machine has two fluid ports at one end: an inlet port OE and an outlet port OS for circulating the heat transfer fluid between the machine core and the hot heat exchanger E1 and cold heat exchanger E2 via a piping connection to transport thermal energy to the sources. The various internal conduits and channels of the machine have the advantage of being able to be combined to discharge into common manifolds also provided inside the machine for the inlet and outlet of the heat transfer fluid, limiting the fluid connection with an application external to the machine to the two ports OE and OS.

[0067] Figures 11 to 14 illustrate another fluidic control device 30 according to an embodiment of the invention. In this embodiment, the fluidic distributors 31 are linear distributors positioned radially in the machine MC 1, i.e., perpendicular to the axis A. Each comprises a hollow body 32 with axis E, mounted in the stator S, and a shutter 33 in the form of a spool that moves in translation relative to the body 32 along the axis E, between at least two switching positions. The contact surface between the body 32 and the shutter 33 can be cylindrical, as in the previous example, to facilitate machining and sealing. However, any other shape of contact surface may be suitable. The outer surface of the body 32 can be arbitrary and, for example, polygonal as illustrated, without this shape being limiting.In the example shown, the body 32 therefore has a first face (on the right in figures 12 and 13) in direct communication with an AMR 2, and a second face (on the left in figures 12 and 13) in direct communication with the circuit portions 5a and 5b.

[0068] In the embodiment shown, the shutter 33 is a double-acting shutter. It has an L-shaped end, the return of the L forming a follower finger 21 which fits into an annular groove 25 of the transmission part 23 for driving the shutter 33 in both directions of translation about the axis T. Of course, any other follower moving in said groove can be suitable, such as a fork with a roller, a pin, or the like.

[0069] In another variant not shown, the obturator 33 may be single-acting. In this case, it has an end forming a follower member held in contact against the transmission part 23 by a deformable part, such as a return spring, a pressurized fluid, a compressible gas, or the like.

[0070] The fluid distributor 31 comprises a first conduit Cl and a second conduit C2, fluidically separated from each other. The first conduit Cl is arranged to be connected to the first section of circuit 5a in a first switching position of the distributor illustrated in [Fig. 12], in which the heat transfer fluid enters the AMR 2 (supply circuit). The body 32 and the obturator 33 each have a supply orifice OA1, OA2 opposite each other. The first conduit Cl has a first supply orifice OA1 provided in a first wall of the body 32, which communicates directly with the first section of circuit 5a and with the supply orifice OA2 of the obturator 33, which communicates with a second supply orifice OA1 provided in a second wall of the body 32 parallel to the first wall, which communicates directly with the AMR 2 at its first end.

[0071] The second conduit C2 is arranged to be connected to the second circuit portion 5b in a second switching position of the distributor illustrated in [Fig. 13], in which the heat transfer fluid exits the AMR 2 (return circuit) at its first end. The body 32 and the obturator 33 each have a return port OR1, OR2 opposite each other. The second conduit C2 has a first return port OR1 provided in the second wall of the body 32, which communicates directly with the AMR 2 at its first end, and with the return port OR2 of the obturator 33, which communicates with a second return port OR1 provided in the first wall of the body 32, which communicates directly with the second circuit portion 5b.

[0072] The supply orifice OA1 and the return orifice OR1 provided in the two parallel walls of the body 32 are separated in the axis E by a distance d corresponding to the existing distance between the supply orifices OA2 and return orifices OR2 of the obturator 33. They are further aligned on the axis E and have a narrow oblong opening, oriented perpendicular to the axis E over a width J - Corresponding to the width of the supply orifices OA2 and return orifices OR2 of the obturator 33. The supply orifices OA1 and return orifices OR1 of the body 32 preferably have an identical cross-section determined to be equal to the cross-section through an AMR 2, in order to avoid pressure losses.

[0073] The supply orifices OA2 and return orifices OR2 provided in the obturator 33 have an enlarged opening that extends along the axis E over a height determined by the magnetic zone corresponding to the angular extent of the magnetic pole 3 on the one hand, and by the non-magnetic zone corresponding to the angular extent between two consecutive magnetic poles 3 on the other. The opening of the supply orifices OA2 and return orifices OR2 extends over a width 1 perpendicular to the axis E, preferably corresponding to the width of the supply orifices OA1 and return orifices OR1 of the body 32. The supply orifices OA2 and return orifices OR2 of the obturator 33 preferably have an identical cross-section. The design of the supply orifices OA1, OA2 and return orifices OR1, OR2 provides the same advantages as those described with reference to the preceding fluidic control device 10.

[0074] Figure 11 shows the eccentric control mechanism 20 as described with reference to Figures 7 and 8, adapted to the fluidic control device 30. It comprises the same parts, namely the drive part 22 fixed to the shaft 8 of the motor 4, and the transmission part 23 assembled to the drive part 22 by a pivot joint, the two parts having the same geometric center D. The transmission part 23 further comprises the groove 25, for example annular, centered on the axis D, in which the follower finger 21' of the shutters 33 is assembled by a sliding joint. In this embodiment, the continuous rotation of the motor 4 of the magnetic arrangement drives the sinusoidal and synchronous translation of the shutters 33 of all the distributors 31, with a phase shift from one to the other determined by their angular arrangement with respect to the magnetic poles 3. In In this configuration, the diametrically opposed obturators 33 move in the same direction of translation T because they are linked to the same transmission part 23, which requires reversing the location of the supply and return ports for these distributors.

[0075] Figure 14 represents a variant of the eccentric control mechanism 20 adapted to the fluidic control device 30. It includes an additional transmission piece 26, parallel to the transmission piece 23, but phase-shifted by 180°. One half of the obturators 33 is linked to the transmission piece 23 with geometric center D, while the other half of the obturators 33, diametrically opposite to the first half, is linked to the additional transmission piece 26 with geometric center D', the two geometric centers D and D' being diametrically opposite with respect to the axis A. This configuration allows the diametrically opposite obturators 33 to move in opposite directions of translation T, which makes it possible to use identical fluidic distributors 31 for all AMRs 2 regardless of their position relative to the control mechanism 20.

[0076] According to variant embodiments of the MC 1 machine, the fluidic control device 10, 30 according to the invention may comprise two fluidic distributors 11, 31 per AMR 2, in direct fluidic contact with the two ends of the AMR. In this case, the fluidic control device 10, 30 may comprise two control mechanisms 20 arranged on either side of the AMR 2 to control the two fluidic distributors 11, 31 per AMR 2. The two control mechanisms 20 are coupled to the motor 4, with or without means for phase-shifting one relative to the other depending on the desired operation.

[0077] The present invention is not limited to the embodiments described but extends to any modification and variant obvious to a person skilled in the art, within the limits of the appended claims. Furthermore, the technical features of the various embodiments and variants mentioned above may be combined, in whole or in part.

Claims

Demands

1. Fluidic control device (10, 30), comprising at least one fluidic distributor (11, 31), comprising at least one first conduit (C1) arranged to be connected to a first circuit portion (5a), and a second conduit (C2) arranged to be connected to a second circuit portion (5b), said first conduit and said second conduit being separate, said fluidic distributor comprising a body (12, 32), and a shutter (13, 33) movable relative to said body between at least two switching positions to alternately conduct said first conduit (C1) and said second conduit (C2), said body and said shutter each comprising at least one supply orifice (OA1, OA2) corresponding to the first conduit (C1) and at least one return orifice (OR1, OR2) corresponding to the second conduit (C2), characterized in that said control device further comprises at least one eccentric control mechanism (20), movable relative to the body (12,32) said at least one hydraulic distributor, said control mechanism (20) being configured to be coupled on the one hand to a rotary actuator (4) and on the other hand to said obturator (13, 33) so as to be able to move it relative to said body (12, 32) in a continuous outward movement, from a continuous inward movement of said rotary actuator.

2. Fluidic control device according to claim 1, characterized in that said control mechanism (20) comprises a drive part (22) integral with said rotary actuator (4), said drive part having a shape of revolution provided with a geometric center (D) distinct from an axis of rotation (A) of said actuator, and a transmission part (23) assembled to said drive part (22) by a pivot joint to be mobile in circular translation, said transmission part (23) being coupled to said obturator (13, 33).

3. A fluidic control device according to claim 2, characterized in that said obturator (13) is rotationally movable about an axis of rotation (B) and comprises a coupling end (21) eccentric with respect to the axis of rotation (B) of said obturator, and in that said transmission part (23) comprises a housing circular (24) housing said coupling end (21) by means of a pivot joint.

4. Fluidic control device according to claim 2, characterized in that said obturator (33) is a double-acting obturator which is movable in translation about a translation axis (T) and includes a follower finger (21'), and in that said transmission piece (23) includes a groove (25) housing said follower finger (21') by a sliding link.

5. Fluidic control device according to claim 2, characterized in that said shutter is a single-acting shutter which is movable in translation along a translation axis (T) and comprises a follower member maintained in contact with the transmission part (23) by a deformable part.

6. Fluidic control device according to claim 3, characterized in that said first conduit (Cl) and said second conduit (C2) are at least partly coaxial and parallel to the axis of rotation (B) of the obturator (13).

7. Fluidic control device according to any one of claims 4 and 5, characterized in that said first conduit (Cl) and said second conduit (C2) each pass through said body (32) transversely to the axis of translation (T) of the obturator (33).

8. Fluidic control device according to any one of claims 5 to 7, characterized in that the opening amplitudes between the forward orifices (OA1, OA2), respectively between the return orifices (OR1, OR2), are not identical to generate short transition times between the opening and closing of said first conduit (Cl), respectively of said second conduit (C2).

9. Fluidic control device according to claim 8, characterized in that the supply orifice (OA1, OA2) and the return orifice (OR1, OR2) of one of the parts of said body (12, 32) or of said obturator (32, 33) are formed by a narrow oblong opening or by a slot, and in that the supply orifice (OA1, OA2) and the return orifice (OR1, OR2) of the other part of said body or of said obturator are formed by an opening wider than said narrow opening.

10. A fluidic control device according to any one of claims 1 to 9, characterized in that it comprises a number N of fluidic distributors (11, 31), arranged in a circle equidistant from an axis of rotation (A) of said rotary actuator (4), and in that that the shutters (11,31) of said distributors are controlled by said eccentric control mechanism (20).

11. Magnetocaloric machine (1) comprising at least one fluidic distributor (11, 31) connected to a fluidic circuit (5), a magnetic arrangement (3), a set of active elements (2) based on magnetocaloric material, said magnetic arrangement and said set of active elements being arranged to be movable relative to each other to create an alternation of magnetic cycles at a defined frequency, and a heat transfer fluid arranged to circulate in said fluidic circuit (5) through said active elements (2), characterized in that it comprises at least one fluidic control device (10, 30) according to any one of claims 1 to 10, comprising at least one fluidic distributor (11, 31) per active element (2), in fluidic contact with a first end of said active element, and in that said fluidic distributor (11,31) is arranged to circulate said heat transfer fluid through said active element (2), alternately in a first direction of circulation in a first portion of the circuit (5a) and in a second direction of circulation, reversed with respect to the first direction of circulation, in a second portion of the circuit (5b) of said fluidic circuit (5), according to a switching frequency between said at least two switching positions of said fluidic distributor which is a multiple of the frequency of the magnetic cycles.

12. Magnetocaloric machine according to claim 11, characterized in that said eccentric control mechanism (20) is coupled to a rotary actuator (4) coupled to said magnetic arrangement (3) or said set of active elements (2).

13. Magnetocaloric machine according to any one of claims 11 and 12, characterized in that the number of supply orifices (OA1, OA2) and return orifices (OR1, OR2) provided in the body (12, 32) and the obturator (13, 33) of said at least one fluidic distributor (11, 31) is equal to the number of magnetic poles (3) of said magnetic arrangement, and in that the switching frequency between the two switching positions of said fluidic distributor (11, 31) is equal to the frequency of the magnetic cycles generated by said magnetic arrangement.

14. Magnetocaloric machine according to any one of claims 11 to 13, characterized in that said fluidic control device comprises two fluidic distributors (11,31) per active element (2), in fluidic contact with the two ends of said active element.

15. Magnetocaloric machine according to claim 14, characterized in that the fluidic control device (10, 30) comprises two control mechanisms (20) arranged on both sides of said set of active elements (2) to control the two fluidic distributors (11, 31) per active element (2), and in that the two control mechanisms are coupled to said rotary actuator (4).

16. Magnetocaloric machine according to any one of claims 11 to 15, characterized in that the opening amplitude of the forward orifice (OA1, OA2) and of the return orifice (OR1, OR2) of one of the parts of said body (12, 32) or of said obturator (13, 33) corresponds substantially to the amplitude of a magnetic pole (3) of said magnetic arrangement.

17. Magnetocaloric machine according to any one of claims 11 to 16, characterized in that said fluidic control device (10, 30) comprises a number N of fluidic distributors (11, 31) or pairs of fluidic distributors, N being equal to the number of active elements (2) of said assembly, arranged in a circle at equal distances from an axis of rotation (A) of said rotary actuator (4), and controlled by said control mechanism(s) (20).

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