FLUIDIC CONTROL DEVICE, IN PARTICULAR FOR A MAGNETOCALORIC MACHINE, AND MAGNETOCALORIC MACHINE EQUIPPED WITH SUCH A DEVICE

Description

Technical field

[0001] The present invention relates to a fluid control device, in particular for a magnetocaloric machine comprising at least one fluid distributor connected to a fluid circuit, said at least one fluid distributor comprising a movable slide arranged to be moved between two distribution positions, said control device comprising a movable cam arranged to cooperate with a follower member, said movable cam being coupled to an actuator, and said follower member being coupled to the movable slide of said fluid distributor, said movable cam comprising a cam profile provided with at least a first section defining a first distribution position, a second section defining a second distribution position, and a transition zone connecting said first section to said second section.

[0002] The present invention also relates to a magnetocaloric machine comprising at least one fluid distributor connected to a fluid 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 movable relatively to each other, and a heat transfer fluid arranged to circulate in said fluid circuit through said active elements. Prior art

[0003] In a known manner, commercially available fluid distributors, also called valves, taps or the like, can be controlled between at least two dispensing positions by any type of manual, mechanical, electrical, electronic or pneumatic actuators. These distributors may include return members, such as compression springs or the like, which make it possible to stress the movable part of the distributor in a first dispensing position, and to return the movable part from a second dispensing position to the first automatic material dispensing position. The movable part of the distributor may be a translationally movable slide, a rotating movable valve, or any other equivalent movable member.

[0004] In the application targeted by the invention, which relates in particular to magnetocaloric machines and in particular magnetic cold generators, fluid distributors, such as those commercially available, are used to circulate a heat transfer fluid in a first thermal loop and then in a second thermal loop of a fluid circuit, the switching frequency between the two thermal loops having to be synchronized with the switching frequency of the magnetocaloric cycles of the machine. The fluid distributors can be controlled by a single-acting movable cam, coupled to a dedicated actuator or to the movable assembly (rotor) of the machine, as described in publication EP 3 102 893 A1 which discloses a fluid control device according to the preamble of claim 1.

[0005] The moving cam usually has an L-shaped cam profile.

[0006] The moving part of the fluid distributors is in this case integral with a roller arranged to circulate on the cam profile, under the action of a pre-stressed return member. The pre-stressing of the return member generates a force perpendicular to the cam profile, causing significant friction between the roller and the cam. This friction induces numerous disadvantages such as: excess torque and therefore excess consumption at the level of the dedicated actuator or the rotor drive motor, premature wear of the cam, the roller and the return member, a delay or even a blockage of the distributors when the return member returns to its pre-stressed position.

[0007] However, in the field of magnetocaloric machines, we are constantly seeking to improve the level of performance to increase the efficiency of converting thermal energy into work and vice versa depending on the operating mode of the machine. To do this, we are constantly seeking to optimize the various parameters, such as the intensity and quality of the magnetic field, the performance of the magnetocaloric material, the heat exchange surface between the heat transfer fluid and the active elements based on magnetocaloric material, the performance of the heat exchangers, etc.

[0008] Publications WO2009 / 087310 and WO2015 / 079313 belonging to the applicant provide an overview of the technical developments already made to magnetocaloric machines, which can be further improved. Statement of the invention

[0009] The present invention aims to propose a new avenue of improvement by acting on the fluidic control of this type of machine or others, to reduce, or even eliminate, the parasitic forces due to friction between the roller and the cam, thus making it possible to optimize the dedicated actuator and / or the movement of the rotor with a minimum of torque, to reduce the energy consumption necessary for the operation of the machine, to achieve better control of the transition zone between two distribution cycles, and better adjustment of the position of the distributors relative to the cam, generating less wear, and making it possible to obtain a more durable and reliable overall operation of the machine, for optimized efficiency.

[0010] For this purpose, the invention relates to a fluid control device of the type indicated in the preamble, characterized in that said cam is a double-acting cam arranged to move said follower member in alternating translation in one direction and in the opposite direction corresponding respectively to said first dispensing position and to said second dispensing position of said distributor, and in that said follower member comprises a first guide element arranged to circulate freely in said cam, and a second guide element arranged to circulate freely in a slide fixed relative to said at least one distributor, to guide said follower member in alternating translation between said two dispensing positions.

[0011] In a preferred form of the invention, the profile of said cam comprises a U-shaped groove arranged to drive said first guide element in both directions of movement.

[0012] Preferably, said follower member extends in an axis perpendicular to the axis of the distributor and to the axis of the profile of said cam. It may advantageously comprise two opposite free ends, the first guide element and the second guide element being fixed respectively to said free ends.

[0013] The first guide element and / or the second guide element of said follower member can be chosen from the group comprising a bearing, a roller, a bearing, a pad, a finger.

[0014] The fixed slide may be provided in a fixing part secured to said at least one fluid distributor, and said at least one distributor may comprise adjustment means arranged to adjust the position of its movable slide and of the follower member relative to said cam.

[0015] According to the embodiments of the invention, said cam may be circular and driven in continuous rotation, said cam profile being in this case closed on itself. Said cam may also be rectilinear and driven in reciprocating translation, said cam profile being in this case open. In all cases, said cam may be formed from a single part, or from at least two complementary parts to facilitate its manufacture and assembly.

[0016] For this purpose also, the invention relates to a magnetocaloric machine of the type indicated in the preamble, characterized in that it comprises a fluid control device as defined above, coupled to said at least one fluid distributor and arranged to circulate said heat transfer fluid in a first thermal loop of said fluid circuit then in a second thermal loop of said fluid circuit as a function of a determined switching frequency.

[0017] Depending on the embodiments of the invention, said fluidic control device may be separated from said magnetic arrangement and said set of active elements, said cam being in this case coupled to a dedicated actuator. Said fluidic control device may also be integrated into said magnetic arrangement and said set of active elements, said cam being in this case coupled to a mobile assembly of the machine carrying said magnetic arrangement or said set of active elements.

[0018] Said magnetocaloric machine may comprise a fluid distributor per active element arranged to distribute said heat transfer fluid alternately in said first thermal loop and in said second thermal loop, said fluid control device comprising in this case a cam.

[0019] It may also comprise two fluid distributors per active element, each arranged to distribute said heat transfer fluid in one of said first thermal loop or said second thermal loop, said fluid control device comprising in this case two parallel cams.

[0020] According to the embodiments of the invention, said at least one distributor may be arranged axially and parallel to the axis of said dedicated actuator or said mobile assembly. It may also be arranged radially and perpendicular to the axis of said dedicated actuator or said mobile assembly.

[0021] When in the magnetocaloric machine, said moving assembly carries said magnetic arrangement, then said cam can be fixed on said moving assembly, and comprise adjustment means arranged to adjust the relative position of the cam with respect to the magnetic poles of said magnetic arrangement. Brief description of the drawings

[0022] The present invention and its advantages will appear better in the following description of several embodiments given as non-limiting examples, with reference to the appended drawings, in which: There Figure 1 is a diagram of the operation of a magnetocaloric machine according to the invention, The Figure 2 is a perspective view of a shrouded magnetocaloric machine, seen from one of its axial ends comprising radially arranged fluid distributors cooperating with a fluid control device according to the prior art, The Figure 3 is a perspective view of an enlarged part of the machine of the Figure 2 , showing axially arranged fluid distributors cooperating with a fluid control device according to the invention, The Figure 4 is a plan view of the enlarged part of the machine of the Figure 3 , There Figure 5is an enlarged axial sectional view of the fluid control device of the invention associated with a fluid distributor, The Figure 6 is a perspective view of a single movable cam forming part of the fluid control device of the invention, The Figure 7 is a schematic diagram of a first variant embodiment of the fluid control device according to the invention, The figure 8 is a schematic diagram of a second variant embodiment of the fluid control device according to the invention, The Figure 9 is a schematic diagram of a third variant embodiment of the fluid control device according to the invention, and The Figure 10 is a schematic diagram of a magnetocaloric machine according to a variant of the invention, in which the fluid distributors and the fluid control device are separated from the rest of the machine. Description of the embodiments

[0023] In the illustrated embodiments, identical elements or parts bear the same reference numbers. Furthermore, terms that have a relative meaning, such as vertical, horizontal, right, left, front, rear, above, below, etc., must be interpreted under normal conditions of use of the invention, and as shown in the figures. The X, Y and Z axes are defined by an orthonormal reference frame illustrated in the various figures. Furthermore, the geometric positions indicated in the description and the claims, such as “perpendicular”, “parallel”, “symmetrical” are not limited to the strict sense defined in geometry, but extend to geometric positions that are close, that is to say which accept a certain tolerance in the technical field considered, without influence on the result obtained.This tolerance is notably introduced by the adverb “sensiblement”, without this term necessarily being repeated before each adjective.

[0024] With reference to the figures, the fluidic control device 10 according to the invention primarily concerns magnetocaloric machines 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. By magnetocaloric machines 1, we mean both thermal generators, also called magnetic cold generators, converting electrical and / or mechanical energy into thermal energy, used in a wide range of applications, such as heating, cooling, air conditioning, tempering, as well as converters of thermal energy, into mechanical and / or electrical energy, making it possible to exploit in particular so-called fatal or lost heat, or the like. An example of a reversible magnetocaloric machine is described in particular in the applicant's publication WO 2021 / 255040.

[0025] There Figure 1schematically illustrates the operation of a known magnetocaloric machine 1, described succinctly, given that it is not the subject of the invention as such. The following description refers to a magnetocaloric machine 1, also called machine 1, operating as a thermal generator. In the example shown, the machine 1 comprises a fixed assembly in the form of a stator S provided with a set of active elements 2 made of magnetocaloric material (MMC), and a mobile assembly in the form of a rotor R provided with a magnetic arrangement forming magnetic poles 3. The rotor R is rotated about an axis A, parallel to the axis X of the orthonormal reference frame, by a motor 4 to subject the active elements 2 to a variation in magnetic field and generate within said active elements 2 a temperature variant in the vicinity of their Curie temperature.Of course, the reverse configuration exists in which the set of active elements 2 is carried by a rotor R and the magnetic arrangement 3 by a stator S, but this configuration complicates the connection of the active elements 2 to the fluid circuit.

[0026] In the Figure 1 and solely for the purpose of explaining the operation of the machine 1, only two active elements 2 and only one magnetic pole 3 are shown. The machine 1 comprises an internal fluid circuit 5 in which a heat transfer fluid circulates via a pump 6 through said active elements 2 and heat exchangers E1 and E2 to restore the thermal energy produced by the active elements 2 to external devices D1, D2. Depending on the applications, the heat transfer fluid may be liquid or gaseous.

[0027] The fluid circuit 5 comprises two thermal loops 5a and 5b of the heat transfer fluid, namely a first thermal loop 5a and a second thermal loop 5b, coupled respectively to a heat exchanger E1, called hot exchanger E1 and a heat exchanger E2, called cold exchanger E2. The two thermal loops 5a, 5b are connected in parallel by a synchronization system arranged to connect in series the active elements 2 to the heat exchangers E1, E2 alternately in one and the other thermal loops 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.

[0028] The fluid circuit 5 further comprises control members 7 for the direction of circulation of the heat transfer fluid in the thermal loops 5a, 5b to impose a single direction of circulation of the heat transfer fluid in the heat exchangers E1, E2, illustrated by the arrows F. It may also comprise a buffer tank 8 of heat transfer fluid connected in series with each of the thermal loops 5a, 5b to compensate for any losses of heat transfer fluid and / or variations in the volumes of the heat transfer fluid as a function of the temperature.

[0029] In reference to the Figure 1 , the operation of the machine 1 is briefly described. In a first thermal cycle, the fluid distributors 11 are in a first distribution position, as illustrated in Figure 1and the heat transfer fluid circulates in a first thermal loop 5a shown in a solid line in a clockwise direction. It passes through the active element 2 located at the bottom of the Figure 1 which undergoes a heating cycle being located in the magnetic field of one of the magnetic poles 3 of the rotor R, passes through the hot exchanger E1 where it returns the collected heat to an external device D1, then passes through the active element 2 located at the top of the Figure 1 which undergoes a cooling cycle being located outside the magnetic field, crosses the cold exchanger E2 where it returns the collected cold to an external device D2.

[0030] In a second thermal cycle, the fluid distributors 11 are in a second distribution position, not shown in the Figure 1, and the heat transfer fluid circulates in a second thermal loop 5b shown in a short broken line in an anticlockwise direction. It passes through the active element 2 located at the bottom of the Figure 1 which now undergoes a cooling cycle being located outside the magnetic field (not shown), passes through the cold exchanger E2 where it returns the collected cold to an external device D2, then passes through the active element 4 located at the top of the Figure 1 which now undergoes a heating cycle being located in the magnetic field of one of the magnetic poles 3 of the rotor R, passes through the hot exchanger E1 where it returns the collected heat to an external device D1.

[0031] The first and second thermal cycles are repeated thanks to the synchronization system which comprises fluid distributors 11 controlled according to a switching frequency determined by a fluid control device 10, object of the invention and described below.

[0032] The magnetocaloric machine 1 as represented in the Figure 1 and in the other figures is described according to a cylindrical configuration in which the rotor R is driven by a continuous rotational movement, without this example being limiting. Indeed, a magnetocaloric machine 1 of linear configuration is entirely conceivable, in which the stator S and the rotor R are laid flat, and the rotor R is driven by an alternating translational movement.

[0033] More particularly to the Figure 2, the magnetocaloric machine 100 comprises at one of its axial ends 101 fluid distributors 102 arranged radially, cooperating with a fluid control device 103 as described in the applicant's publication WO 2021 / 255040. The machine 100 comprises active elements (not visible) carried by a material holder 104 forming a stator S, provided with fluid connectors 105 accessible from the axial end shown. The fluid connectors 105 comprise at least one fluid inlet and one fluid outlet per active element. The piping allowing the connection of the fluid connectors 105 to the distributors 102 is not shown so as not to overload the figure.

[0034] The fluid distributors 102 are in the example shown slide valves. The fluid control device 103 comprises a movable cam 106 and follower rollers 107 arranged to circulate on the cam 106. The cam 106 is coupled to an actuator which can be a dedicated actuator 20 ( Figure 10 ) or the actuator of the rotor R of the machine 100, namely the motor 4 as shown ( Figures 1 and 2). If it is a dedicated actuator 20, a control unit (not shown) is provided to synchronize the operation of the dedicated actuator 20 of the cam 106 with the motor 4 of the rotor R, in the case of a magnetic cold generator. In this example, the cam 106 has a single-acting cam profile, i.e. active in only one direction of movement. The cam profile in this case has an L-shaped section. In addition, the follower rollers 107 are integral with the slides (not visible) of the distributors 102 and the distributors 102 have pre-stressed return members (not visible) which secure the follower rollers 107 against the cam profile, necessarily generating significant friction between the roller 107 and the cam 106, which is to be avoided.

[0035] Referring now to the figures 3 to 6, the fluid distributors 11 according to the invention, also called distributors 11, are preferably slide valves, in which the slide (not visible) is movable in alternating translation between two distribution positions, free, without any prestressing, nor return member, to open and close inlet and outlet orifices of the distributors according to a determined distribution pattern. The fluid control device 10 according to the invention, also called control device 10, comprises for this purpose a movable cam 12, also called cam 12, having a double-acting cam profile, that is to say active in the two opposite directions of movement. The cam profile has in this case a U-shaped section. In the example shown, the movable cam 12 is directly secured to the rotor R of the machine 1 and cooperates with a follower member 13 secured to the slide of the fluid distributors 11.Of course, the movable cam 12 could also be coupled to a dedicated actuator 20 as shown in . Figure 10 .

[0036] Cam 12 is shown in detail in Figure 6. It comprises a ring 120, the axis of revolution of which is intended to coincide with the axis A of the rotor R, provided with a circular groove 121 in its outer periphery, open radially along the axis Z and extending along the axis Y. The groove 121 defines a U-shaped cam profile, and comprises in the example shown two first diametrically opposed sections T1, defining a first distribution position, two second diametrically opposed sections T2, defining a second distribution position, alternating with the first sections T1, and four transition zones ZT each connecting a first section T1 to an adjacent second section T2. ​​Thus, the number of pairs of sections T1+T2 provided in the cam 12 corresponds to the number of magnetic poles 3 of the machine 1.The cam 12 can therefore comprise a pair of sections T1+T2 if the machine 1 comprises a single magnetic pole 3, and more than two pairs of sections T1+T2 if the machine 1 comprises more than two magnetic poles 3. The sections T1 and T2 are rectilinear, parallel to the Y axis and therefore perpendicular to the X axis. The first sections T1 and the second sections T2 are offset from each other by a stroke C corresponding to the stroke of the movable slides of the distributors 11 between two distribution positions. Finally, the transition zones ZT are inclined relative to the Y axis to ensure the continuity of the cam profile between the different sections T1 and T2. The angle of inclination of the transition zones ZT is determined to reduce the switching time as much as possible, but without penalizing the continuous circulation of the follower member 13 in the groove 121. This angle can be between 10° and 60° without these values ​​being limiting.

[0037] The cam 12 also comprises a fixing flange 122 on its inner periphery perforated with a plurality of fixing holes 123. The cam 12 is intended to be fixed directly and securely to the moving assembly of the machine 1. In the example shown, the moving assembly of the machine 1 comprises two coaxial rotors R, namely an inner rotor and an outer rotor, between which is arranged the fixed assembly forming a stator S carrying the active elements. In this example, the moving cam 12 is fixed to the outer rotor R shown very partially by its outer casing in the figures. The plurality of fixing holes 123 forms means for adjusting the angular position of the cam 12 relative to the magnetic poles 3 carried by the rotors R.Indeed, each first section T1 of the cam 12 must be aligned with one of the magnetic poles 3, and each second section T2 of the cam 12 must be aligned with the empty or non-magnetic zone separating two magnetic poles 3, or vice versa. Thus, each section T1 and T2 arranged in the cam 12 corresponds exactly to a working cycle of the machine, which corresponds in this specific application, to a magnetocaloric heating cycle and a magnetocaloric cooling cycle. The movable cam 12 is illustrated in the form of a single part but can of course be formed of two complementary parts, each corresponding to a half-ring, or of more than two complementary parts, each corresponding to an annular sector, said parts being able to be identical or not, in order to facilitate its manufacture and its assembly on the rotor R.

[0038] In the example shown in the figures 3 to 5, the fluid distributors 11 are arranged axially, that is to say parallel to the axis A of the rotor R or the axis X of the orthonormal reference frame, and perpendicular to the axis Y of the cam 12. They are represented by parallelepiped blocks provided with inlet orifices on one side and outlet orifices on the opposite side. In this example, these may be 5 / 2-way, 4 / 2-way or similar valves, each of which can ensure the distribution of the heat transfer fluid in the two thermal loops 5a, 5b of the fluid circuit 5. In this case, the machine 1 comprises a number of fluid distributors 11, equal to the number of active elements 2. The distributors 11 may also comprise 4 / 2-way, 3 / 2-way or similar valves, each of which can ensure the distribution of the heat transfer fluid in only one of the two thermal loops 5a, 5b of the fluid circuit 5, thus avoiding mixing of the heat transfer fluid during the switching phases in the transition zones ZT.In this case, the number of 3 / 2 or 4 / 2 distributors required for the same machine 1 is double the number of 5 / 2 distributors.

[0039] The distributors 11 are fixed to a fixed assembly of the machine 1, such as the material holder 9 of the stator S, each by means of a fixing part 14 which extends axially in the axis X, extends at least on one side of the distributors 11 to overlap the cam 12, then extends radially in the axis Z to the material holder 9. The fixing part 14 further comprises, in line with the cam 12, a slide 15, formed in the example shown, by an oblong slot of axis X, and the length of which is at least equal to the stroke C of the slide. The slide of each distributor 11 is extended by a control rod 16 carrying at its free end a follower member 13.Each distributor 11 may further comprise an adjustment means, for example in the form of a screw-nut system or similar, making it possible to adjust the relative position of the follower member 13 with respect to the cam 12, and simultaneously the relative position of the slide with respect to the inlet and outlet orifices of the distributor 11.

[0040] The follower member 13 is part of the fluid control device 10 of the invention and cooperates with the movable cam 12 which generates its displacement in alternating translation along the X axis in one direction and in the opposite direction corresponding respectively to a first distribution position and to a second distribution position of the distributor 11. In this example, the control rod 16 of the slide has a T shape, the bar of the T forming the follower member 13. Thus, the follower member 13 extends in the Z axis perpendicular to the X axis of the distributor 11 and to the Y axis of the cam 12.

[0041] The follower member 13 comprises a rectilinear bar 130, having two opposite free ends, respectively carrying a first guide element 131 and a second guide element 132. The first guide element 131 is arranged to circulate freely in the groove 121 of the cam 12 along the Y axis. The second guide element 132 is arranged to circulate freely in the slide 15 of the fixing part 14 of the distributors 11 along the X axis, and thus guide the follower member 13 in alternating translation between the two positions of the distributor 11, eliminating its other degrees of freedom, and in particular its rotation around the X axis of the distributor 11.In the example shown, the guide elements 131, 132 are made up of bearings, but could be made up of rollers, bearings, pads, fingers, or any other rotating or sliding member, the essential thing being to create a rolling contact or a low coefficient of friction contact respectively with the cam 12 and the slide 15 to reduce or even eliminate friction. It is also possible to add lubrication and to enclose the control device 10 in a casing containing said lubricant.

[0042] There Figure 5shows a construction detail of the follower member 13. The bearings forming respectively the first guide element 131 and the second guide element 132 are attached to the free ends of the bar 130 and fixed by means of fixing screws 133, 134 in a threaded bore 135. The bar 130 can be an integral part of the control rod 16 or be attached. Of course, any other equivalent embodiment of the follower member 13 may be suitable. This Figure 5 also shows a guide ring 17 arranged to guide in translation the control rod 16 of the distributor drawer, attached to the fixing part 14, or to the control rod 16, or to both if it is a double guide ring.

[0043] In the figures 3 to 5, the machine 1 comprises for each active element 2 a fluid distributor 11 arranged axially and controlled by a single movable cam 12 arranged at one of the axial ends of the machine 1. This example of construction is not the only one, and the figures 7 to 9 schematically illustrate other examples of construction of the fluid control device 10 according to the invention.

[0044] There Figure 7shows a fluid distributor 11 arranged axially carried by a fixing part 14, and controlled by two single-acting cams 12' arranged in opposition in the two axial ends of the machine 1. The two single-acting cams 12' are equivalent to the double-acting cam 12 described previously. In this example, the distributor 11 comprises two aligned control rods 16, connected to the two opposite ends of its slide, and each carrying at its free end a follower member 13 cooperating with one of the cams 12'. This type of assembly makes it possible to balance the guiding and control forces of the fluid distribution system. In this variant, the single fluid distributor 11 per active element 2 is a 5 / 2-way or 4 / 2-way valve.In a variant not shown, the single fluid distributor 11 can be replaced by two distributors in the form of 3 / 2-way or 4 / 2-way valves, connected to each other and each controlled by one of the two cams 12'.

[0045] There figure 8 shows a fluid distributor 11 arranged radially along the Z axis, in one of the axial ends of the machine 1, and controlled by a single cam 12 arranged in said axial end, open axially in the X axis. In this example, the distributor 11 is a 5 / 2-way valve, the control rod 16 of the slide extends in the Z axis and the follower member 13 extends in the X axis.

[0046] There Figure 9 shows a similar arrangement to the figure 8 , in which the fluid distributor 11 is arranged radially along the Z axis but controlled by two single-acting cams 12' in opposition, as in the Figure 7. In this variant, the single fluid distributor 11 per active element 2 is a 5 / 2-way or 4 / 2-way valve. In a variant not shown, the single fluid distributor 11 can be replaced by two distributors in the form of 3 / 2-way or 4 / 2-way valves, each controlled by one of the two cams 12'.

[0047] There Figure 10shows a magnetocaloric machine 1 according to an alternative embodiment of the invention, in which the fluid distributors 11 and the fluid control device 10 are separated from the rest of the machine, which notably comprises the set of active elements 2 and the magnetic arrangement 3, one carried by a stator S and the other by a rotor R. In this configuration, the cam 12 is coupled to a dedicated actuator 20 such as a motor, and is guided in rotation in a fixed support (not shown). The fluid distributors 11 are connected to said fixed support by their fixing parts 14. The fluid distributors 11 are further connected to the active elements 2 by appropriate fluid conduits 21.

[0048] The dedicated actuator 20 can be controlled by a control unit (not shown) designed to synchronize the operation of the dedicated actuator 20 of the cam 12 with that of the rotor R, in particular when the magnetocaloric machine 1 operates as a magnetic cold generator. This is not the case when the magnetocaloric machine 1 operates as a thermal converter arranged to recover thermal energy from lost fatal heat, since it is the fluidic control device 10 which induces the rotation of the rotor R. In this operating mode, the rotor R can be coupled to an electrical generator to produce electrical energy.

[0049] The fluid control device 10 shown in the Figure 10 corresponds to that represented in the Figure 7, namely that the fluid distributors 11 are positioned axially and controlled by two single-acting cams 12' arranged in opposition. Of course, the other radial arrangements illustrated in the figures 8 And 9 can also be adapted to this variant of realization, as well as any other compatible configuration.

Claims

1. A fluidic control device (10), in particular for a magnetocaloric machine (1) comprising at least one fluidic distributor (11) connected to a fluidic circuit (5), said at least one fluidic distributor comprising a movable slide disposed to be displaced between two distribution positions, said control device (10) comprising a movable cam (12) disposed to cooperate with a follower member (13), said cam (12) being coupled to an actuator, and said follower member (13) being coupled to the slide of said distributor (11), said cam (12) comprising a cam profile provided with at least a first section (T1) defining a first distribution position, with a second section (T2) defining a second distribution position, and with a transition zone (ZT) connecting said first section (T1) to said second section (T2), the control device being characterized in that said cam (12) is a double-acting cam disposed to displace said follower member (13) in reciprocating translation in one direction and in the opposite direction respectively corresponding to said first distribution position and to said second distribution position of said distributor (11), and in that said follower member (13) comprises a first guide element (131) disposed to move freely in said cam (12), and a second guide element (132) disposed to move freely in a slideway (15) which is fixed with respect to said at least one distributor (11), in order to guide said follower member (13) in reciprocating translation between said two distribution positions.

2. The fluidic control device as claimed in claim 1, characterized in that the profile of said cam (12) comprises a U-shaped groove (121) disposed to drive said first guide element (131) in both displacement directions.

3. The fluidic control device as claimed in any one of claims 1 and 2, characterized in that said follower member (13) extends along an axis perpendicular to the axis of the distributor (11) and to the axis of the profile of said cam (12).

4. The fluidic control device as claimed in any one of claims 1 to 3, characterized in that said follower member (13) comprises two opposed free ends, and in that the first guide element (131) and the second guide element (132) are respectively mounted on said free ends.

5. The fluidic control device as claimed in any one of claims 1 to 4, characterized in that the first guide element (131) and / or the second guide element (132) of said follower member (13) is selected from the group comprising a bearing, a roller, a bearing bush, a shoe, a finger.

6. The fluidic control device as claimed in any one of claims 1 to 5, characterized in that the fixed slideway (15) is provided in a mounting part (14) which is integral with said at least one fluidic distributor (11), and in that said at least one distributor (11) comprises adjustment means disposed to adjust the position of its movable slide and of the follower member (13) with respect to said cam (12).

7. The fluidic control device as claimed in any one of claims 1 to 6, characterized in that said cam (12) is circular and driven in continuous rotation, and in that said cam profile is closed on itself.

8. The fluidic control device as claimed in any one of claims 1 to 6, characterized in that said cam is rectilinear and driven in reciprocating translation, and in that said cam profile is open.

9. The fluidic control device as claimed in any one of claims 1 to 8, characterized in that said cam (12) is formed by a single part, or by at least two complementary parts.

10. A magnetocaloric machine (1) comprising at least one fluidic distributor (11) connected to a fluidic circuit (5), a magnetic arrangement (3), a set of active elements (2) based on magnetocaloric material, said magnetic arrangement (3) and said set of active elements (2) being disposed to be movable relative to each other, and a heat transfer fluid disposed to circulate in said fluidic circuit (5) through said active elements (2), characterized in that it comprises a fluidic control device (10) as claimed in any one of claims 1 to 9, coupled to said at least one fluidic distributor (11) and disposed to cause said heat transfer fluid to circulate in a first thermal loop (5a) of said fluidic circuit (5) then in a second thermal loop (5b) of said fluidic circuit (5) as a function of a specific switching frequency.

11. The magnetocaloric machine as claimed in claim 10, characterized in that said fluidic control device (10) is separate from said magnetic arrangement (3) and from said set of active elements (2), and in that said cam (12) is coupled to a dedicated actuator (20).

12. The magnetocaloric machine as claimed in claim 10, characterized in that said fluidic control device (10) is integrated into said magnetic arrangement (3) and into said set of active elements (2), and in that said cam (12) is coupled to a movable assembly (R) of the machine carrying said magnetic arrangement (3) or said set of active elements (2).

13. The magnetocaloric machine as claimed in any one of claims 10 to 12, characterized in that it comprises one distributor (11) per active element (2) disposed to distribute said heat transfer fluid alternately in said first thermal loop (5a) and in said second thermal loop (5b), and in that said fluidic control device (10) comprises a cam (12).

14. The magnetocaloric machine as claimed in any one of claims 10 to 12, characterized in that it comprises two distributors (11) per active element (2) each disposed to distribute said heat transfer fluid in one of said first thermal loop (5a) or said second thermal loop (5b), and in that said fluidic control device (10) comprises two parallel cams (12, 12').

15. The magnetocaloric machine as claimed in any one of claims 12 to 14, characterized in that said at least one distributor (11) is disposed axially and parallel to the axis of said dedicated actuator (20) or said movable assembly (R).

16. The magnetocaloric machine as claimed in any one of claims 12 to 14, characterized in that said at least one distributor (11) is disposed radially and perpendicular to the axis of said dedicated actuator (20) or said movable assembly (R).

17. The magnetocaloric machine as claimed in any one of claims 12 to 16, in which said movable assembly (R) supports said magnetic arrangement (3), characterized in that said cam (12) is mounted on said movable assembly (R), and in that said cam (12) comprises adjustment means (123) disposed to adjust the relative position of the cam (12) with respect to the magnetic poles (3) of said magnetic arrangement.