EP3201441B1 - Electromagnetic actuator for an internal combustion engine - Google Patents

Description

The invention relates to the control of valves in an internal combustion engine. More specifically, it relates to an electromagnetic actuator for a valve in such an engine.

The valve control must meet the following constraints. First, the movement of the valves must be rapid and precise, to facilitate the admission, respectively the evacuation, of the gases. Then, the valve stroke must be sufficient to guarantee a large flow of gases, whether it is intake or exhaust. Finally, the forces transmitted to the valves must be significant (especially during evacuation), to overcome the pressure prevailing in the combustion chamber.

Traditionally, the control of valves in internal combustion engines is carried out mechanically by a distribution system comprising one or more camshaft (s) which drive the valves, either directly or indirectly via rocker arms. A camshaft is coupled in rotation to the crankshaft by a belt or a timing chain.

This technique has proven itself, but it has a major drawback: it does not allow any regulation of the valve control, except occasionally when adjusting (essentially manual) the distribution, during which the camshafts are calibrated. Variable timing systems have, of course, been devised, but their development is complex, which undoubtedly prevented their generalization to the entire vehicle fleet. In addition, there may appear at high speeds a phenomenon of panic of the valves, which no longer follow the movement controlled by the camshaft, generally due to a malfunction of the valve return springs. If the panic of the valves generally produces a drop in power, it can go as far as causing a breakdown of the engine due to impacts of the valves on the pistons.

An alternative technique for valve control is electromagnetic actuation. In this technique, each valve is driven by means of an electromagnetic actuator. One or more magnets generate an electromagnetic field capable of move, by the force of Laplace, a support on which is wound a coil traversed by an electric current and with which the valve is integral.

• une armature définissant au moins deux circuits magnétiques superposés, à savoir un circuit magnétique supérieur et un circuit magnétique inférieur, chaque circuit magnétique incluant un aimant, une pièce polaire externe annulaire ferromagnétique, en contact avec l'aimant, et un noyau central ferromagnétique, la pièce polaire et le noyau définissant entre eux un entrefer ;
• un équipage mobile incluant :
  • ∘ une carcasse munie d'un corps tubulaire plongé dans l'entrefer,
  • ∘ une bobine enroulée dans l'entrefer sur le corps de la carcasse ; et
  • ∘ une soupape solidaire de la carcasse.

This technique is known in particular from the French patent FR 2 797 297 , which describes an electromagnetic actuator for an internal combustion engine valve, comprising:

• an armature defining at least two superimposed magnetic circuits, namely an upper magnetic circuit and a lower magnetic circuit, each magnetic circuit including a magnet, an annular ferromagnetic external pole piece, in contact with the magnet, and a ferromagnetic central core, the pole piece and the core defining between them an air gap;
• a mobile crew including:
  • ∘ a carcass fitted with a tubular body immersed in the air gap,
  • ∘ a coil wound in the air gap on the body of the carcass; and
  • ∘ a valve integral with the carcass.

If this actuator is satisfactory in theory, its practical implementation is delicate because the forces generated on the valve may prove to be insufficient.

In addition, certain engines, generally engines developing a large power, may require the use, for the same cylinder, of two intake valves and two exhaust valves.

One objective is to propose an electromagnetic actuator which responds to all of the constraints associated with valve control: good speed, good control, sufficient valve stroke, importance of the forces transmitted, and which is adaptable to high power motors.

• une armature définissant un circuit magnétique incluant :
  • ∘ un aimant ;
  • ∘ une pièce polaire externe ferromagnétique en contact avec l'aimant, la pièce polaire délimitant un alésage primaire ;
  • ∘ un noyau primaire ferromagnétique logé dans l'alésage primaire et définissant avec la pièce polaire un entrefer primaire ;
• un équipage mobile primaire incluant :
  • ∘ une carcasse primaire munie d'un corps tubulaire plongé dans l'entrefer primaire,
  • ∘ une bobine primaire enroulée dans l'entrefer primaire sur le corps de la carcasse primaire ;
  • ∘ une soupape solidaire de la carcasse primaire ;

dans lequel :

• la pièce polaire délimite un alésage secondaire voisin de l'alésage primaire ;
• le circuit magnétique inclut un noyau secondaire ferromagnétique logé dans l'alésage secondaire et définissant avec la pièce polaire un entrefer secondaire ;
• l'actionneur comprend un équipage mobile secondaire incluant :
  • ∘ une carcasse secondaire munie d'un corps tubulaire plongé dans l'entrefer secondaire ;
  • ∘ une bobine secondaire enroulée dans l'entrefer secondaire sur le corps de la carcasse secondaire ;
  • ∘ une soupape solidaire de la carcasse secondaire.

To this end, an electromagnetic actuator for an internal combustion engine valve is proposed, first of all, which comprises:

• an armature defining a magnetic circuit including:
  • ∘ a magnet;
  • ∘ an external ferromagnetic pole piece in contact with the magnet, the pole piece defining a primary bore;
  • ∘ a ferromagnetic primary core housed in the primary bore and defining with the pole piece a primary air gap;
• a primary mobile crew including:
  • Primaire a primary carcass fitted with a tubular body immersed in the primary air gap,
  • ∘ a primary coil wound in the primary air gap on the body of the primary carcass;
  • ∘ a valve integral with the primary carcass;

in which :

• the pole piece defines a secondary bore close to the primary bore;
• the magnetic circuit includes a ferromagnetic secondary core housed in the secondary bore and defining with the pole piece a secondary air gap;
• the actuator includes a secondary mobile assembly including:
  • ∘ a secondary carcass fitted with a tubular body immersed in the secondary air gap;
  • ∘ a secondary coil wound in the secondary air gap on the body of the secondary carcass;
  • ∘ a valve integral with the secondary carcass.

• la rapidité du mouvement des soupapes, facilitant l'admission et l'évacuation des fluides dans ou hors du cylindre,
• une bonne course des soupapes et une force de déplacement des soupapes suffisante pour permettre de vaincre les efforts exercés par les gaz dans le cylindre, notamment lors de l'évacuation des gaz.

This actuator is thus adapted to an engine having four valves per cylinder while ensuring essential functions such as:

• the speed of movement of the valves, facilitating the admission and evacuation of fluids into or out of the cylinder,
• a good valve stroke and a displacement force of the valves sufficient to overcome the forces exerted by the gases in the cylinder, in particular during the evacuation of the gases.

• la bobine primaire et la bobine secondaire comprennent un circuit d'alimentation commun ;
• la bobine primaire et la bobine secondaire comprennent chacune un circuit d'alimentation distinct ;
• l'armature comprend un couvercle permettant de solidariser le noyau primaire et le noyau secondaire avec la pièce polaire ;
• le couvercle comprend deux doigts venant en prise chacun avec le noyau primaire ou le noyau secondaire, les deux doigts étant séparés l'un de l'autre d'un entraxe ;
• l'entraxe des doigts du couvercle est légèrement inférieur à un entraxe mesuré entre l'alésage primaire et l'alésage secondaire ;
• la bobine primaire et la bobine secondaire sont respectivement constituées d'une bobine primaire supérieure et d'une bobine primaire inférieure et, d'une bobine secondaire supérieure et d'une bobine secondaire inférieure ;
• l'actionneur électromagnétique comprend une pièce polaire supérieure et une pièce polaire inférieure.

Various additional characteristics can be provided, alone or in combination:

• the primary coil and the secondary coil comprise a common supply circuit;
• the primary coil and the secondary coil each comprise a separate supply circuit;
• the frame comprises a cover making it possible to secure the primary core and the secondary core with the pole piece;
• the cover comprises two fingers each engaging with the primary core or the secondary core, the two fingers being separated from each other by a center distance;
• the center distance of the cover fingers is slightly less than a center distance measured between the primary bore and the secondary bore;
• the primary coil and the secondary coil consist respectively of an upper primary coil and a lower primary coil and, an upper secondary coil and a lower secondary coil;
• the electromagnetic actuator comprises an upper pole piece and a lower pole piece.

It is proposed, secondly, an internal combustion engine comprising an electromagnetic actuator as presented above and, thirdly, a motor vehicle comprising an engine as presented previously.

• la figure 1 est une vue en perspective de dessus d'un véhicule automobile muni d'un moteur à combustion interne ayant au moins un actionneur électromagnétique pour soupape ;
• la figure 2 est une vue schématique en coupe d'un cylindre du moteur de la figure 1 ;
• la figure 3 est une vue en coupe de l'actionneur électromagnétique selon un premier mode de réalisation ;
• la figure 4 est une vue éclatée en perspective de dessus de l'actionneur électromagnétique ;
• la figure 5 est une vue en coupe de l'actionneur électromagnétique selon un deuxième mode de réalisation ;
• la figure 6 est une vue en coupe selon l'axe C-C de la figure 5.

Other objects and advantages of the invention will appear in the light of the description of an embodiment, given below with reference to the appended drawings in which:

• the figure 1 is a perspective view from above of a motor vehicle provided with an internal combustion engine having at least one electromagnetic actuator for a valve;
• the figure 2 is a schematic sectional view of a cylinder of the engine of the figure 1 ;
• the figure 3 is a sectional view of the electromagnetic actuator according to a first embodiment;
• the figure 4 is an exploded perspective view from above of the electromagnetic actuator;
• the figure 5 is a sectional view of the electromagnetic actuator according to a second embodiment;
• the figure 6 is a sectional view along the CC axis of the figure 5 .

On the figure 1 a motor vehicle 1 is represented, here a particular vehicle, but it could be any other type of vehicle: utility, truck, construction machine.

The vehicle 1 is equipped with an internal combustion engine 2 provided with cylinders 3 defining combustion chambers 4 and in which pistons 5 are slidably connected, by connecting rods 6, to a crankshaft 7 whose rotation drives the wheels 8 of vehicle 1 via a transmission (not shown).

The engine 2 comprises, for each cylinder 3, four valves 9 distributed in pairs, namely two intake valves 9a and two exhaust valves 9b .

In the remainder of this description, we will speak of valves 9, without making any particular reference to their use for intake or exhaust.

Each valve 9 comprises a rod 10 which extends along a central X axis which defines an axial direction. At one end of the rod 10 is formed a head 11. Each valve 9 is movable in translation relative to a cylinder head 12 of the engine 2 between a closed position in which the head 11 of the valve 9 is pressed against a seat 13 for close off an intake duct 14 (or, respectively, an exhaust duct 15 ) and an open position in which the head 11 is moved away from the seat 13 to put the cylinder 3 in communication with the intake duct 14 (or, respectively, the exhaust duct 15 ).

In the example illustrated, the engine 2 is of the direct injection diesel type and comprises, for this purpose, an injector 16 which opens directly into the combustion chamber 4 , but it could be any other type of combustion engine internal: petrol, indirect injection, hybrid.

Each valve 9 is controlled in position by an electromagnetic actuator 17 . This actuator 17 is itself controlled by a computerized control unit 18 equipped with a programmable processor.

The actuator 17 is shown in section on the figures 3 and 5 respectively according to a first and a second embodiment and in exploded view on the figure 4 , according to the first embodiment. The actuator 17 comprises an armature 19 as well as two crews 20, 21 mobiles, namely a primary mobile crew 20 and a secondary mobile crew 21 .

• un aimant 22 ;
• au moins une pièce polaire 23a, 23b ferromagnétique, et dans l'exemple illustré, une pièce supérieure 23a et une pièce inférieure 23b, entre lesquelles l'aimant 22 est pris en sandwich ;
• un noyau 24 primaire ferromagnétique de forme sensiblement cylindrique définissant, avec les pièces 23a, 23b polaires, un entrefer 25 primaire ;
• un noyau 26 secondaire ferromagnétique de forme sensiblement cylindrique définissant, avec les pièces 23a, 23b polaires, un entrefer 27 secondaire, et
• un couvercle 28 venant en prise avec les deux noyaux 24, 26 comme il sera décrit ci-après.

The frame 19 includes:

• a magnet 22 ;
• at least one pole piece 23a, 23b ferromagnetic, and in the example illustrated, an upper piece 23a and a lower piece 23b, between which the magnet 22 is sandwiched;
• a ferromagnetic primary core 24 of substantially cylindrical shape defining, with the pole pieces 23a, 23b , a primary air gap 25 ;
• a ferromagnetic secondary core 26 of substantially cylindrical shape defining, with the pole pieces 23a, 23b , a secondary air gap 27 , and
• a cover 28 engaging with the two cores 24, 26 as will be described below.

Advantageously, the armature 19 comprises a primary bore 29 and a secondary bore 30 , adjacent to the primary bore 29 , in which the primary core 24 and the secondary core 26 are received respectively, the primary and secondary bores 29, 30 being formed. jointly in the pole pieces 23a, 23b and the magnet 22.

The cover 28 is provided with a plate 31 and two fingers 32 capable of being housed each in one of the primary and secondary cores 24, 26 . According to the embodiment shown in the figures, and as can be seen in the figure 6 , the two fingers 32 are spaced from each other by a center distance C1 slightly smaller than a center distance P1 between the primary bore 29 and the secondary bore 30 which causes a reduction in the air gaps 25, 27 primary and secondary in a central region of the electromagnetic actuator 17 .

The primary movable element 20 comprises a primary carcass 33 , an upper primary coil 34 , a lower primary coil 35 and a valve 9.

The primary carcass 33 comprises a tubular body 36 open at an upper end 37 and provided with an upper annular groove 38 and a lower annular groove 39 in which are respectively housed the upper primary coil 34 and the lower primary coil 35 .

In addition, the primary carcass 33 comprises at a lower end, a bottom 40 onto which the valve 9 is screwed by means of screws 41. In a variant not shown in the figures, the valve 9 is welded to the bottom 40 of the carcass 33 .

Similarly, the secondary movable element 21 comprises a secondary carcass 42 , an upper secondary coil 43 , a lower secondary coil 44 and a valve 9.

The secondary carcass 42 comprises a tubular body 45 open at an upper end 46 and provided with an upper annular groove 47 and a lower annular groove 48 in which the upper primary coil 43 and lower primary coil 44 are respectively housed.

In addition, the secondary carcass 42 comprises at a lower end, a bottom 49 onto which the valve 9 is screwed by means of screws 41.

According to the embodiment shown in the figures, the upper and lower primary coils 34, 35 and the upper and lower secondary coils 43, 44 consist of a wire of circular section. However, to reduce the primary and secondary air gaps 25, 27 , the coils can be made of a wire of rectangular section.

The electromagnetic actuator 17 is assembled in the manner described below.

The frame 19 is first assembled by bonding the magnet 22 to the upper part 23a and the lower part 23b .

The cover 28 is also glued to the primary core 24 and to the secondary core 26 by its fingers 32 each coming into engagement with one of the cores 24, 26.

Finally, the primary core 24 and the secondary core 26 are inserted respectively into the primary bore 29 and into the secondary bore 30 and held in position by means of a flange (not shown) which holds the cover 28 with one polar pieces 23a, 23b .

Advantageously, the fixing means chosen for assembling the frame 19 is bonding which then makes it possible to to overcome the problems of disturbances of the magnetic field, in particular caused when the assembly is carried out by means of screws.

For the assembly of the primary movable element 20 , the upper primary coil 34 is inserted into the upper annular groove 38 of the primary carcass 33 , the lower primary coil 35 is inserted into the lower annular groove 39 of the primary carcass 33 and the valve 9 is assembled on the bottom 40 of the primary carcass 33 by means of the screws 41.

It is the same for the secondary mobile unit 21 : the upper secondary coil 43 is inserted in the upper annular secondary groove 47 of the secondary carcass 42 , the lower secondary coil 44 is inserted in the lower secondary annular groove 48 of the carcass 42 secondary and the valve 9 is assembled on the bottom 49 of the secondary carcass 42 by means of the screws 41. In a variant not shown in the figures, the valve 9 is welded to the bottom 49 of the carcass 42.

The electromagnetic actuator 17 is finally assembled by inserting the primary movable element 20 and the secondary movable element 21 respectively in the primary bore 29 and the secondary bore 30 .

In operation, an electric current is transmitted to the coils 34, 35, 43, 44 in order to interact with a magnetic field generated by the magnet 22 (shown in phantom in the figures) intended to translate the moving parts 20, 21 in the bores 29, 30 of the frame 19.

Advantageously, the coils 34, 35 and 43, 44 are constructed so that the same current flows in an opposite direction depending on whether it borrows the upper coil 34, 43 or the lower coil 35, 44 of the same equipment 20 , 21 mobile.

In order to separate the valves 9 from the armature 19 and thus to put in fluid connection the intake pipe 14 or the exhaust pipe 15 with the combustion chamber 4 of the cylinder 3, a positive current is transmitted to the coils 34, 43 upper and 35, 44 lower. The flow in the opposite direction of the current between the upper coil 34, 43 and the lower coil 35, 44 generates, by the law of Laplace, a force allowing the movement of mobile 20, 21 crews.

It then suffices to reverse the polarity of the current flowing in the upper coils 34, 43 and in the lower coils 35 , 44 to bring the valves 9 closer to the armature 19 and thus remove the fluid connection between the intake duct 14 or the exhaust duct 15 and the combustion chamber 4 of the cylinder 3.

Advantageously, the moving parts 20, 21 are controlled independently of one another. For example, the secondary movable element 21 can remain closed while the primary movable element 20 is open.

Adjusting the intensity of the current transmitted to the coils 34, 35, 43, 44 makes it possible to vary the speed of opening and closing of the valves 9 but also to vary the spacing of the valves 9 relative to the armature 19 and thus regulate the flow rate of fluid flowing from the intake pipe 14 to the combustion chamber 4 or from the combustion chamber 4 to the exhaust pipe 15 .

One advantage of reducing the primary and secondary air gaps 25, 27 by the difference between the centers C1 and P1 lies in the increase in the intensity of the magnetic field, at equal current intensity, in a central region of the actuator. 17 electromagnetic with respect to the intensity of the magnetic field in a peripheral region opposite the central region.

The presence of an upper coil 34, 43 and of a coil 35, 44 for each of the moving parts 20, 21 makes it possible to increase the forces transmitted to the valves 9, to the benefit of the efficiency of the electromagnetic actuator 17 .

A variant of the electromagnetic actuator 17 is shown on the figures 5 and 6 .

This variant implements a means of cooling the electromagnetic actuator 17 . Indeed, the use of high electric currents to generate the forces necessary for the movement of the valves 9, generates, under certain conditions of use of the electromagnetic actuator 17 , an excess of heat and, thus, a heating of the actuator 17 electromagnetic which, combined with the heat generated by the operation of the motor 2 itself, can prematurely degrade the electromagnetic actuator 17 .

In order to cool the electromagnetic actuator 17 , the magnet 22 is provided with two cooling conduits 50 each opening into the primary bore 29 or into the secondary bore 30 .

The primary and secondary carcasses 33, 42 are then provided with an annular belt 51 , substantially central, which, when the electromagnetic actuator 17 is assembled, is in line with a cooling duct 50 so that a cooling fluid , injected into the frame 19, does not encounter any obstacle as soon as it enters the primary and secondary bores 29, 30 .

Advantageously, the belt 51 has a height such that in the high position, in the low position or in an intermediate position between the high position and the low position of the moving parts 20, 21 , the cooling conduits 50 are facing this belt 51.

In addition, the difference between the centers C1 and P1 also makes it possible to increase the distance between the primary and secondary cores 24, 26 and the cooling conduits 50 opening into the primary and secondary bores 29, 30 , so as to facilitate the introduction of the cooling fluid into the air gaps 25, 27 primary and secondary.

Advantageously, the cooling fluid is injected, from a compressor, through pipes 52 which are housed in the cooling conduits 50 . This coolant is shown on the figures 5 and 6 by dotted lines.

The electromagnetic actuator 17 is then cooled by direct contact of the fluid with the upper and lower primary coils 34, 35 and the upper and lower secondary coils 43, 44 . The hot fluid having stored part of the heat of the coils 34, 35, 43, 44, is removed from the electromagnetic actuator 17 at its upper and lower ends and then recovered in a motor circuit (not shown).

However, if the fluid is air, and, for energy saving and recycling purposes, the hot air could be recovered to be injected into the engine 2, after possible cooling and possible compression.

Alternatively, a fluid other than air could be used such as, for example, water or oil which has a higher thermal capacity and heat transfer coefficient than air.

According to an embodiment not shown in the figures, the cooling conduits 50 are produced in the pole pieces 23a, 23b or jointly in the pole pieces 23a, 23b and in the magnet 22.

According to the embodiment shown in the figures, the cooling conduits 50 are each produced on a different face of the electromagnetic actuator 17 .

In a variant not shown in the figures, the cooling conduits 50 are adjacent and are produced on the same face of the electromagnetic actuator 17 .

The electromagnetic actuator 17 which has just been presented comprises numerous advantages.

Firstly, the electromagnetic actuator 17 offers the advantage of reducing the size of the motor 2. In fact, a motor 2 provided with these electromagnetic actuators 17 does not use a camshaft, which reduces the size of the motor 2 , especially in height. The gain in size makes it possible to reduce the height of the engine compartment of a vehicle 1 and thus allows a more aerodynamic shape of the vehicle 1, which then becomes less fuel-consuming and has a more attractive silhouette.

Secondly, the actuators 17 are adaptable to engines 2 having four valves 9 per cylinder 3. In fact, the compactness of the actuators 17 allows the control of two adjacent valves 9 for the intake or exhaust of a cylinder 3 of engine 2 .

Third, the electromagnetic actuator 17 allows precise control of the valves 9. Each valve 9 of the same electromagnetic actuator 17 can be controlled independently of the other. For this, each primary coil 34, 35 and secondary 43, 44 is supplied by a dedicated electrical circuit. On the contrary, if the two valves are controlled simultaneously, a single electrical circuit may be used. The precision of the control is provided by the regulation of the intensity of the current transmitted to the coils 34, 35, 43, 44 primary and secondary and then ensures rapid opening and closing of the valves 9.

Fourth, the electromagnetic actuator 17 generates a magnetic field large enough to counter the pressure prevailing in the combustion chamber 4 and authorize the opening of the valves 9. Thus, an electromagnetic actuator 17 as described can be used both in admission to the exhaust of the cylinders 3 in place of the camshafts.

Finally, the cooling of the electromagnetic actuator 17 ensures a better lifetime of the actuator 17, by regulating its operating temperature, and allows the use of the electromagnetic actuator 17 on motors 2 which can reach speeds. high operating torque, maximum power.

Claims (9)

1. An electromagnetic actuator (17) for a valve (9) of an internal combustion engine (2), which includes:

   - an armature (19) defining a magnetic circuit including:

   ∘ a magnet (22);

   ∘ a first external ferromagnetic polar piece (23a, 23b) in contact with the magnet (22), this polar piece (23, 23b) delimiting a primary bore (29);

   ∘ a ferromagnetic primary core (24) housed in the primary bore (29) and defining with the polar piece (23a, 23b) a primary air gap (25) ;

   - a primary mobile assembly (20) including:

   ∘ a primary casing (33) provided with a tubular body (36) immersed in the primary air gap (25),

   ∘ a primary coil (34, 35) wound in the primary air gap (25) on the body (36) of the primary casing (33);

   ∘ a valve (9) integral with the primary casing (33) ;

   characterized in that:

   - the armature (19) includes a second polar piece (23b), between which the magnet (22) is sandwiched,

   - the polar pieces (23a, 23b) and the magnet (22) delimit the primary bore (29) and a secondary bore (30) close to the primary bore (29);

   - the magnetic circuit includes a ferromagnetic secondary core (26) housed in the secondary bore (30) and defining with the polar piece (23a, 23b) a secondary air gap (27);

   - the actuator (17) includes a secondary mobile assembly (21) including:

   ∘ a secondary casing (42) provided with a tubular body (45) immersed in the secondary air gap (27);

   ∘ a secondary coil (43, 44) wound in the secondary air gap (27) on the body (45) of the secondary casing (42);

   ∘ a valve (9) integral with the secondary casing (42).
2. The electromagnetic actuator (17) according to Claim 1, characterized in that the primary coil (34, 35) and the secondary coil (43, 44) include a common supply circuit.
3. The electromagnetic actuator (17) according to Claim 1, characterized in that the primary coil (34, 35) and the secondary coil (43, 44) each include a distinct supply circuit.
4. The electromagnetic actuator (17) according to any one of the preceding claims, characterized in that the armature (19) includes a cover (28) permitting the primary core (24) and the secondary core (26) to be secured with the polar piece (23a, 23b).
5. The electromagnetic actuator (17) according to the preceding claim, characterized in that the cover (28) includes two fingers (32) each being engaged with primary core (24) or the secondary core (26), the two fingers (32) being separated from one another by an axial distance (C1).
6. The electromagnetic actuator (17) according to the preceding claim, characterized in that the axial distance (C1) of the fingers (32) of the cover (28) is slightly less than an axial distance (P1) measured between the primary bore (29) and the secondary bore (30) .
7. The electromagnetic actuator (17) according to any one of the preceding claims, characterized in that the primary coil (34, 35) and the secondary coil (43, 44) are respectively constituted by an upper primary coil (34) and a lower primary coil (35) and an upper secondary coil (43) and a lower secondary coil (44).
8. An internal combustion engine (2) including an electromagnetic actuator (17) according to one of the preceding claims.
9. A motor vehicle (1) including an internal combustion engine (2) according to the preceding claim.

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