Magnetic actuator
The magnetic actuator design addresses energy inefficiencies by mechanically controlling a movable section to reduce holding forces, enabling energy-efficient disengagement and stable positioning without external energy input.
Patent Information
- Authority / Receiving Office
- FR · FR
- Patent Type
- Applications
- Current Assignee / Owner
- SOCOMEC SPA
- Filing Date
- 2024-12-17
- Publication Date
- 2026-06-19
AI Technical Summary
Existing magnetic actuators require significant energy consumption to disengage, which is inefficient, especially in applications where energy scarcity is a concern.
A magnetic actuator design featuring a movable section that can be mechanically controlled to switch between closed and open positions, reducing the magnetic holding force and allowing disengagement without high energy consumption, utilizing a magnetic core, frame, and magnetic excitation source to maintain stable positions without external energy.
Enables disengagement of the actuator with reduced energy consumption by minimizing the opposing forces required, making it suitable for energy-efficient applications and systems requiring bistable or monostable configurations.
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Abstract
Description
Title of the invention: Magnetic actuator technical field
[0001] The present invention relates to the field of actuators. More particularly, it concerns a magnetic actuator, especially a monostable or bistable one. The invention provides a magnetic actuator that can be disengaged by a mechanical action, for example by a manual control, in an energy-efficient manner. Prior art
[0002] Magnetic actuators conventionally use the magnetic force generated by a driving current to achieve mechanical movement, most often linear. This type of actuator is available in various embodiments and is typically characterized by its great simplicity. Consequently, numerous variants are found in various mechatronic systems requiring the movement of a mechanical part driven by an electrical source. These actuators can be referred to indefinitely by the terms "electromagnet," "solenoid," "magnetic actuator," etc.
[0003] Magnetic actuators are mostly either monostable or bistable. A monostable actuator has one stable position in the "unpowered" state and another stable position in the "powered" state, the "powered" state here referring to the pilot current. A bistable actuator has two different stable positions in the "unpowered" state, and the change of state is achieved by the intervention of the pilot current.
[0004] The monostable or bistable configuration depends on the type of actuation required in the application and the available energy. Nowadays, due to energy scarcity, bistable actuators, which require no energy to maintain two positions, are more commonly used. Monostable actuators remain advantageous in applications where safety is paramount, for example, when a function is guaranteed only if a power source is present.
[0005] Some magnetic actuators include a manual control allowing disengagement. When a magnetic actuator is disengaged, it is then held in a given position, regardless of the pilot current.
[0006] Documents US4683452 A, CN201369250 Y, FR3110025 A1 and EP0532586 A1 propose disengageable magnetic actuators. The solutions described in these documents have the drawback that disengaging the actuator requires significant energy consumption. Description of the invention
[0007] The present invention aims to overcome these drawbacks by proposing a magnetic actuator comprising: - a magnetic core, mobile along an axis of translation, between two extreme positions, - at least one frame, configured to form with at least the magnetic core, when it is in its first extreme position, at least one magnetic circuit, and - at least one magnetic excitation source configured to generate a magnetic flux flowing through the magnetic circuit.
[0008] The magnetic actuator according to the invention is particular in that the housing comprises at least one moving section, said at least one moving section being mechanically controlled in order to be: - either in a closed position, in which the magnetic circuit is closed and can be traversed by a portion of the magnetic flux generated by the magnetic excitation source, the magnetic flux traversing the magnetic circuit allowing, at least in certain configurations of the magnetic core and / or the magnetic excitation source, the magnetic core to be maintained in at least one of its extreme positions with a holding magnetic force - either in the open position, in which said magnetic circuit is open, the intensity of the holding magnetic force being reduced compared to the closed position.
[0009] Thanks to these arrangements, the forces used to accomplish the disengagement do not directly oppose the forces maintaining the magnetic core in a possibly stable state, the disengagement of the actuator can be carried out without consuming a large amount of energy.
[0010] Said magnetic actuator may further include a return means, generating a return force contributing to attracting the magnetic core towards a second extreme position, or to maintaining the magnetic core in the second extreme position, which is a simple and effective embodiment of the invention.
[0011] The two extreme positions of the magnetic core can be stable in the absence of energy injected from outside into the magnetic actuator, which makes it possible to obtain a bistable actuator, offering two different positions whose maintenance does not require the consumption of energy.
[0012] The frame can be configured to form at least two magnetic circuit sections, each section being able to form, with at least the magnetic core when it is in its first extreme position, a separate magnetic circuit, said frame then being able to comprise a moving section for each magnetic circuit, the mechanical controls of each moving section being synchronized so that with the moving sections all open or closed at the same time, this type of frame being able to channel a larger part of the magnetic flux and therefore generate greater magnetic forces, and being easier to manufacture.
[0013] At least one moving section can be configured so that when its passage from the closed position to the open position is initiated, the magnetic field lines running through the air gap generated by this movement between the moving section and the rest of the frame have, with the direction of the movement of the moving section at the level of this air gap, an angle greater than or equal to 60°, which makes it possible to shear the magnetic forces of the magnetic circuit, and thus to break them using less energy than in the case of tearing.
[0014] Said magnetic excitation source may include at least one permanent magnet, generating a magnetic force contributing to maintaining the magnetic core in the first extreme position and / or in the second extreme position, said permanent magnet being able to constitute a segment of the magnetic circuit formed by at least the casing and the magnetic core when it is in its first extreme position, which is a simple and effective embodiment of the invention.
[0015] At least one moving section can be configured so that when its passage from the closed position to the open position is initiated, at least a part of the moving section, located in the vicinity of an air gap generated by this movement between the moving section and the rest of the frame, approaches the permanent magnet, the magnetic force generated by the permanent magnet helping to promote this movement, which makes it possible to further reduce the energy required to disengage the magnetic actuator.
[0016] At least one of said at least one permanent magnet can be attached to the magnetic core, and can follow the magnetic core in its movements between the two extreme positions, which makes it possible to gain in the holding force of the magnetic core, and in the actuation dynamics.
[0017] The passage of said at least one movable section from the closed position to the open position and vice versa can be done by a rotational movement, along an axis of rotation orthogonal to the axis of translation, the axes of rotation and translation being able to be non-secant, which is a movement easy to implement, and easily adaptable to different applications.
[0018] The passage of said at least one moving section from the closed position to the open position and vice versa can be done by a translational movement, along a translational axis parallel to the translational axis of the actuator, which is an embodiment well suited to certain actuator configurations or actuator integration.
[0019] The permanent magnet may have a cylindrical shape, preferably along the axis of translation, said moving section being able to have at its nearest end of the permanent magnet, at the level where an air gap is generated during the opening movement of the moving section, a contour having two sides and a center, the sides being further from the axis of the cylinder of the permanent magnet, and more extended along this axis, than the center, when the moving section is in the closed position, which makes it possible to increase the proximity between the moving section in the vicinity of the air gap and the permanent magnet, and therefore to optimize the use of the magnetic field emitted by the permanent magnet to further reduce the energy required to disengage the magnetic actuator.
[0020] Said magnetic actuator may include a manual actuation means allowing said at least one moving section to pass from the closed position to the open position and vice versa, the disengagement then being able to be carried out easily and quickly by an operator.
[0021] The magnetic excitation source may include at least one pilot coil comprising at least one winding arranged around at least one section of the magnetic circuit, the pilot coil being configured to be able to carry an electric current, the magnetic flux generated by the pilot coil being able to be driven to move the magnetic core from one extreme position to the other, which is a simple and efficient embodiment of the invention.
[0022] Said at least one pilot coil may comprise at least one winding arranged around the axis of translation, around at least one section of said magnetic core, which is a simple and effective embodiment of the invention.
[0023] The present invention also relates to a method for disengaging a magnetic actuator according to the invention, comprising the following steps: - use of the magnetic actuator, wherein at least one moving section is in the closed position, the magnetic flux generated by the magnetic excitation source and flowing through the magnetic circuit allowing, at least in certain configurations of the magnetic core and / or the magnetic excitation source, the magnetic core to be held in at least one of its extreme positions, with a holding magnetic force, - putting said at least one moving section in the open position, the intensity of the magnetic holding force then being reduced compared to the closed position.
[0024] Thanks to these arrangements, the forces used to achieve disengagement do not directly oppose the forces maintaining the magnetic core in a possibly stable state, the force required to achieve disengagement is lower, and therefore reduces energy consumption.
[0025] The present invention further relates to an electrical circuit switching device comprising at least one fixed contact and at least one moving contact, said at least one moving contact being movable between at least one engaged position in which said at least one moving contact is in contact with said at least one fixed contact and the electrical circuit is closed, and a triggered position in which said at least one moving contact is not in contact with said at least one fixed contact and the electrical circuit is open, said switching device being characterized in that it further comprises a magnetic actuator according to the invention, and in that the movements of the moving contact are controlled by said magnetic actuator.
[0026] Thanks to these arrangements, the forces implemented to achieve a mechanical opening of the cutting device do not directly oppose the forces maintaining the magnetic core in a possibly stable state, the force required for the mechanical opening of the cutting device is lower, and therefore this opening can be carried out without consuming a large amount of energy. Brief description of the drawings
[0027] 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:
[0028] [Fig-1] [Fig. 1] is a perspective view of a first embodiment of the magnetic actuator according to the invention, with the moving sections in the closed position,
[0029] [Fig.2] [Fig.2] is a perspective view of the magnetic actuator of [Fig.1], with the moving sections in the open position,
[0030] [Fig.3] [Fig.3] is a perspective view of the magnetic actuator of [Fig.1], with the moving sections in intermediate positions, [Fig.4] [Fig.4] is a cross-sectional view of a first embodiment of the magnetic actuator according to the invention, with the moving sections in the closed position.
[0031] [Fig. 5] [Fig. 5] is a cross-sectional view of the magnetic actuator of [Fig. 4], the with the movable sections in the open position,
[0032] [Fig.6] [Fig.6] is a perspective view of a third embodiment of the magnetic actuator according to the invention, with the moving sections in the closed position,
[0033] [Fig.7] [Fig.7] is a perspective view of a fourth embodiment of the magnetic actuator according to the invention, comprising movable sections with translational motion,
[0034] [Fig.8] [Fig.8] is a perspective view of a fifth embodiment of The magnetic actuator according to the invention, comprising movable sections requiring the removal of magnetic forces in order to open them.
[0035] [Fig.9] [Fig.9] is a cross-sectional view of a sixth embodiment of the magnetic actuator according to the invention, comprising two pilot coils,
[0036] [Fig. 10] [Fig. 10] is a perspective view of a cutting device according to the invention, in the open position,
[0037] [Fig.11] [Fig.11] is a perspective view of the cutting device of [Fig.10], in the closed position. Description of the implementation methods
[0038] In the illustrated embodiments, identical elements or parts bear the same reference numbers. Furthermore, 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 "substantially," without this term necessarily being repeated before each adjective.
[0039] With reference to the figures, the magnetic actuator 1 according to the invention comprises a magnetic core 2, movable about a translational axis 3 between two extreme positions, a first extreme position and a second extreme position. In the figures, the first extreme position corresponds to the lower position of the magnetic core 2, and the second extreme position corresponds to the upper position of the magnetic core 2.
[0040] The magnetic actuator 1 also includes at least one magnetic excitation source. The magnetic excitation source preferably includes at least one pilot coil 4 and / or at least one permanent magnet 9.
[0041] The magnetic actuator 1 further comprises a carcass 5. The carcass 5 is made of a ferromagnetic material and forms, with the magnetic core 2, and possibly with other magnetic elements of the actuator 1, at least one magnetic circuit 6.
[0042] In embodiments in which the magnetic excitation source includes a pilot coil 4, the magnetic circuit 6 passes inside a winding of the pilot coil 4 and then forms a contour passing outside this winding. The magnetic circuit 6 is thus configured to channel a portion of the magnetic flux generated by the pilot coil 4 when it carries an electric current. In this way, by varying the excitation current of the pilot coil, it is possible to control the magnetic flux flowing through the magnetic circuit 6. This magnetic flux is then controlled to either maintain the magnetic core 2 in one of its extreme positions, with a certain force magnetic holding, i.e. moving the magnetic core 2 from one of its extreme positions to the other.
[0043] The winding of the pilot coil 4 is, for example, arranged around the translation axis 3 and around at least a portion of the magnetic core 2. In this case, the portion of the magnetic core 2 around which the pilot coil 4 is located varies depending on the position of the magnetic core 2. In a preferred embodiment illustrated in the figures, the magnetic core and the winding of the pilot coil 4 have generally cylindrical shapes, and the axis of these cylinders is the translation axis 3. Other arrangements are possible without departing from the scope of the present invention. Indeed, the winding of the pilot coil 4 can be arranged anywhere around a section of the magnetic circuit 6, for example, around a section of the frame 5.
[0044] However, the magnetic actuator 1 according to the invention may not include a pilot coil 4, for example in the case where the magnetic excitation source includes at least one permanent magnet 9. This permanent magnet 9 is preferably a segment of the magnetic circuit 6.
[0045] As illustrated in the examples in the figures, the casing 5 can be made of a rectangular plate folded to surround the different elements of the actuator, and having an opening allowing the magnetic core to emerge in at least one of its extreme positions.
[0046] When reference is made in the present application to the movements of the magnetic core 2, these movements can therefore be considered in relation to the frame 5, which is largely fixed, with the exception of its movable sections described below.
[0047] The housing 5 comprises at least one moving section 7, which forms a section of the magnetic circuit 6 described above. In the remainder of this application, when the moving section 7 is referred to, it shall be understood that this reference shall also apply to all the moving sections 7 of the magnetic actuator, unless explicitly stated otherwise. The moving section 7 can be placed in the closed position, in which the magnetic circuit 6 is closed, and the behavior of the actuator is as described above. The moving section 7 can also be placed in the open position. In this case, the magnetic circuit 6, at the level of the housing 5, no longer channels the magnetic flux generated by the magnetic excitation source to the same extent. Thus, when the moving section 7 is in the open position, the magnetic force holding the magnetic core 2 in one of its extreme positions is reduced.The magnetic holding force can be reduced by at least 20% compared to the situation in which at least one moving section 7 is closed. This reduction in holding force can be greater than or equal to 50%, preferably greater than or equal to 90%, for example greater than or equal to 99%.
[0048] In some cases, the decrease in the magnetic holding force caused by the opening of the moving section(s) 7 is such that the position of the magnetic core 2 is no longer induced by the magnetic flux flowing through the magnetic circuit 6. For example, if the magnetic actuator 1 has a pilot coil 4, the position of the magnetic core 2 may no longer be controlled by the current flowing through the pilot coil 4. If the magnetic core 2 is, at the moment of opening the moving section 7, in a stable position, if this stable position is based on the magnetic flux generated by a permanent magnet 9, then the magnetic core may leave its stable position.
[0049] In the present application, the expression "closed magnetic circuit" does not exclude the presence of one or more air gaps located on the magnetic circuit 6, between various magnetic elements. The magnetic circuit 6 is considered closed when the reluctances generated on the magnetic circuit 6 by these air gaps are sufficiently low to allow the position of the magnetic core 2 to be controlled by the current flowing through the pilot coil 4 and / or maintained by the magnetic flux generated by the permanent magnet 9 as described above and below.
[0050] The opening of the moving section 7 can be designated in this application as a disengagement of the magnetic actuator 1.
[0051] The magnetic actuator 1 according to the invention can be a monostable actuator, meaning that one of the extreme positions of the magnetic core 1 is a stable position, or a bistable actuator, meaning that both extreme positions of the magnetic core 1 are stable positions. A stable position of the magnetic core is understood to mean that maintaining this position does not require an energy input from outside the magnetic actuator. Energy from the outside is understood to mean, for example, electrical energy flowing through an excitation coil forming part of the magnetic actuator 1, or mechanical energy originating, for example, from a manual control of the magnetic actuator 1.If the magnetic actuator 1 includes a return means and / or a permanent magnet, the energies emitted and / or stored by these internal elements of the magnetic actuator 1 are not considered to originate from outside the magnetic actuator 1.
[0052] In order to obtain a stable position of the magnetic core 2, the magnetic actuator 1 may include at least one return means 8, such as a spring. The return means 8 generates a restoring force that acts on the magnetic core 2, so that in the absence of magnetic flux flowing through the magnetic circuit 6, if the magnetic core 2 is in a certain position, the first or second extreme position, it is held in that position by the effect of the spring. For example, in the embodiment illustrated in Figures 4 and 5, the upper position is a position stable, by the effect of the spring 8. The restoring means 8 is preferably configured so that the restoring force it generates acts along the translation axis 3. The restoring means 8 can be located partially in the magnetic core 2, as illustrated in figures 4 and 5, or it can be located outside the magnetic core 2; for example by moving the spring 8 of figures 4 and 5 so that it extends from the top of the magnetic core 2.
[0053] It should be noted that a return means 8 may also be present in the magnetic actuator 1 without it participating in maintaining the magnetic core 2 in a stable position. Indeed, other elements internal or external to the actuator may exert forces on the magnetic core 2, possibly opposing the return force generated by the return means 8, and sometimes with a greater intensity. The return means 8 may then be used, for example, to help attract the magnetic core 2 into one of its extreme positions in combination with other forces, for example, the magnetic forces from the pilot coil 4 and / or the permanent magnet 9.
[0054] The return means 8 is preferably made of a non-magnetic material, so as not to interfere with the magnetic flux or fluxes involved in the magnetic actuator 1.
[0055] In order to obtain a stable position of the magnetic core 2, the magnetic actuator 1 may include at least one permanent magnet 9. The permanent magnet 9 generates a magnetic force that acts on the magnetic core 2, such that if the magnetic core 2 is in a certain position, and where applicable in the absence of current flowing through the pilot coil 4, the first or second extreme position, it is held in that position by the effect of the permanent magnet 9. For example, in the embodiment illustrated in Figures 4 and 5, the lower position is a stable position, by the effect of the permanent magnet 9. The permanent magnet 9 is preferably configured so that the magnetic force it generates acts along the translational axis 3. To achieve this, it can be arranged close to the stable position, as illustrated in Figures 4 and 5. Alternatively, it can be arranged to the side, but be a polarizing magnet, as illustrated in [Fig. 9].The permanent magnet 9 preferably forms a section of the closed magnetic circuit 6 described above, and it can in particular be placed, as illustrated in figures 4 and 5, between the frame 5 and the magnetic core 2. It can also be fixed to the magnetic core 2, and follow its movements between its two extreme positions, or be fixed to the fixed part of the frame 5, and not follow these movements.
[0056] It should be noted that a permanent magnet 9 may also be present in the magnetic actuator 1 without it participating in maintaining the magnetic core 2 in a stable position. Indeed, other elements internal or external to the actuator may exert forces on the magnetic core 2, possibly opposing the magnetic force generated by the permanent magnet 9, and sometimes with a greater intensity. The permanent magnet 9 can then be used, for example, to help attract the magnetic core 2 to one of its extreme positions in combination with other forces, for example, the magnetic forces from the pilot coil 4. For example, if we consider that Figures 4 and 5 represent a monostable magnetic actuator 1, the magnetic force of the permanent magnet 9 can be, regardless of the position of the magnetic core 2, weaker than the force of the spring 8, the only stable position therefore being the upper position of the magnetic core 2.The magnetic force generated by the permanent magnet 9 can then be used to complement the magnetic force generated by the pilot coil 4 to move the magnetic core 2 to the lower position and maintain it there, thereby reducing energy consumption and decreasing the size of the pilot coil 4, thus saving space.
[0057] On the contrary, if we consider that figures 4 and 5 represent a bistable magnetic actuator 1, the magnetic force of the permanent magnet 9 is greater than the restoring force of the spring 8 when the magnetic core 2 is in the lower position, and the restoring force of the spring 8 is greater than the magnetic force of the permanent magnet 9 when the magnetic core 2 is in the upper position, these two positions being therefore stable, in particular if the magnetic actuator 1 includes a pilot coil 4, in the absence of power supply to the pilot coil 4.
[0058] As illustrated by way of example in the figures, the magnetic actuator 1, when it includes a permanent magnet 9, also preferably includes a magnetic channel 10 located between the magnet and the magnetic core 2, allowing the magnetic flux to be channeled between these elements. The magnetic channel 10 then constitutes a section of the magnetic circuit 6.
[0059] In another embodiment illustrated in [Fig. 9], the magnetic actuator 1 is bistable and comprises two pilot coils 4 and a polarizing permanent magnet 9. The permanent magnet 9 ensures that the two extreme positions of the magnetic core 2 are stable, as the current flowing through the pilot coils 4 is controlled to move from one position to the other. The housing 5 then forms two magnetic circuits 6 with the magnetic core 2, each configured to channel a portion of the magnetic flux emitted by one of the pilot coils 4, and each magnetic circuit 6 comprising a movable section 7.
[0060] The carcass 7 can be configured to form a single section of magnetic circuit between the extreme positions of the magnetic core 2, as illustrated by way of example in Figures 6 to 8. The magnetic actuator 1 then comprises a single magnetic circuit 6.
[0061] In a preferred embodiment, illustrated by way of example in Figures 1 to 5, the frame 7 is configured to form two magnetic circuit sections, each section forming, together with the magnetic core 2 and optionally one or more permanent magnets, a separate magnetic circuit 6. Each magnetic circuit 6 then comprises a moving section 7. Preferably, the moving sections 7 of the different magnetic circuits are controlled synchronously, for example, by means of a mechanical control integrated into the magnetic actuator 1, to allow a single disengagement movement of the magnetic actuator 1. The movements of the moving sections 7 can then be identical, or different, for example, two symmetrical rotations, as illustrated in Figures 2, 3, and 5, or two asymmetrical rotations. The magnetic circuits 6 can then be symmetrical with respect to the translational axis 3.
[0062] The magnetic actuator 1 preferably comprises a support 11, made of a non-magnetic material, located around the magnetic core 2 and, where applicable, between the magnetic core 2 and the pilot coil 4. The support 11 guides the movements of the magnetic core 2 between its extreme positions. The support 11 may have a cylindrical shape, conforming to the shape of the magnetic core 2 and, optionally, the pilot coil 4. If the magnetic actuator 1 includes a pilot coil 4, the support 11 may have a flange lia at each end to prevent direct contact between the pilot coil 4 and the rest of the magnetic actuator 1, for example, the housing 5 and, optionally, the magnetic channel 10, as shown in Figures 4 and 5.
[0063] The movable section 7 can be moved in any type of motion to transition from an open to a closed state, and vice versa. More specifically, it can, for example, undergo a rotational movement, as illustrated in Figures 2, 3, 5, and 8, or a translational movement, as illustrated in [Fig. 7]. Other rotational movements are possible, for example, about an axis parallel to the translational axis 3, and other translational movements are also possible, about any axis, the chosen movement depending in particular on the environment in which the magnetic actuator 1 is intended to be placed.
[0064] When the moving section 7 is set in motion to move from its closed position to its open position, at least one air gap is created and enlarges between the moving section 7 and the frame 5. In the embodiments illustrated in Figures 2, 3, and 5, there are two air gaps. Once this air gap generates sufficient reluctance, the moving section 7 is considered open and the magnetic actuator 1 is disengaged. The opening of this air gap is achieved by applying a mechanical force to the moving section 7, which must be greater than the magnetic forces present in the magnetic circuit 6 and tending to maintain the magnetic circuit 6. The force The mechanical force required is important not only to initiate the opening of the moving section 7, but also to continue this opening to a certain point. For example, in the example illustrated in [Fig. 3], the maximum torque required during the opening movement of the moving section 7 occurs when the moving section 7 has already rotated 25° around its axis. To reduce the mechanical force needed to disengage the clutch, it is preferable that this force not be directly opposed to these magnetic forces. This direct opposition of forces is found in the geometry illustrated in [Fig. 8], in which the moving section 7 must be pulled in the same direction as the magnetic forces, thus disengaging the clutch requires overcoming the magnetic forces. In certain specific cases, such a geometry may be preferred because it can offer other advantages.However, in most cases, to reduce the disengagement force, it is preferable to implement a different geometry, in which the movement of the moving section 7 in the vicinity of the newly created air gap follows a direction at an angle to the magnetic field lines emitted by the pilot coil 4 and / or the permanent magnet 9, the amplitude of the angle preferably being greater than 60°, for example, a right angle. Examples of such geometries are illustrated in Figures 2, 3, 5, and 7. The right angle allows the magnetic forces of the magnetic circuit to be broken by shearing, which requires less force than pulling.
[0065] In a preferred embodiment of the magnetic actuator 1 comprising a permanent magnet 9, an example of which is illustrated in Figures 2 and 3, the moving section 7 is configured so that, when it is moved to the open position, the portion of the moving section 7 located near an air gap being created approaches the permanent magnet. This allows a portion of the magnetic attraction force of the permanent magnet 9 to be used to support the movement of the moving section 7 towards its open position, this movement having to be carried out despite the magnetic forces favoring keeping the magnetic circuit 6 closed. This feature can be implemented whether the movement of the moving section 7 is translational, rotational, or otherwise.
[0066] In order to optimally benefit from the attraction exerted by the permanent magnet 9 to open the moving section 7, the moving section 7 can have a particular geometry so that, during its opening movement, its shape closely matches the shape of the permanent magnet. Thus, when the moving section 7 undergoes a rotational movement, and the permanent magnet 9 is cylindrical, as illustrated in Figures 2 and 3, a specific contour of the moving section 7 can be provided. This specific contour includes, in particular, two sides 7a, extending further forward than a center 7b. When the moving section 7 is in the closed position, the sides 7a are further from the axis of the permanent magnet, which coincides with the center 7b. In the example illustrated with the translation axis 3, this contour is such that the two sides 7a extend further forward than the center 7b along the axis of the permanent magnet when the moving section 7 is in the closed position. For example, the contour can have a rounded shape to pass as close as possible to the permanent magnet 9 when the moving section 7 is opened. Easier to manufacture, the contour can have a half-H shape, as illustrated, for example, in Figures 2 and 3. Without these arrangements, if the contour of the moving section 7 had been flat at this point, it would have had to be level with the center 7b, resulting in a greater distance between the sides of the contour and the permanent magnet when the moving section 7 was opened, and thus a less efficient use of the attractive force of the permanent magnet 9.
[0067] The magnetic actuator 1 may also include a manual actuation means, allowing the moving section(s) 7 to be moved from the closed position to the open position and vice versa.
[0068] The magnetic actuator 1 according to the invention is therefore disengageable, and can be disengaged according to a process comprising the following steps: - use of the magnetic actuator 1, in which the moving section 7 is in the closed position, the magnetic flux generated by the magnetic excitation source and flowing through the magnetic circuit 6 allowing, at least in certain configurations of the magnetic core 2 and / or the magnetic excitation source, the magnetic core 2 to be held in at least one of its extreme positions with a holding magnetic force, - putting the moving section 7 in the open position, the intensity of the magnetic holding force is then reduced compared to the closed position.
[0069] The magnetic actuator 1 can be integrated into an electrical switching device 12, as illustrated by way of example in Figures 10 and 11. The switching device 12 comprises at least one fixed contact 13 and at least one moving contact 14. The moving contact 14 is movable between: - an engaged position, in which it is in contact with the fixed contact 13, and the electrical circuit is closed, illustrated as an example in [Fig. 1 1], and - a triggered position, in which it is not in contact with the fixed contact 13 and the electrical circuit is open, illustrated as an example in [Fig. 10].
[0070] The movements of the movable contact 14 are then controlled by the magnetic actuator 1.
[0071] The present invention is not limited to the field of switching devices, however, and the magnetic actuator 1 can be integrated into any relevant system.
[0072] The present invention is of course not limited to the embodiments described but extends to any modification and variant obvious to a person of sound mind. within the limits of the attached claims. Furthermore, the technical characteristics of the various embodiments and variants mentioned above may be combined, in whole or in part.
Claims
Demands
1. A magnetic actuator (1) comprising: - a magnetic core (2), movable about a translational axis (3), between two extreme positions, - at least one housing (5), configured to form with at least the magnetic core (2), when it is in its first extreme position, at least one magnetic circuit (6), and - at least one magnetic excitation source configured to generate a magnetic flux flowing through the magnetic circuit (6), characterized in that the housing (5) comprises at least one movable section (7), said at least one movable section (7) being mechanically controlled to be placed: - either in the closed position, in which the magnetic circuit (6) is closed, and can be traversed by a portion of the magnetic flux generated by the magnetic excitation source, the magnetic flux flowing through the magnetic circuit (6) allowing, at least in certain configurations of the magnetic core (2) and / or the magnetic excitation source,to maintain the magnetic core (2) in at least one of its extreme positions with a holding magnetic force, - either in the open position, in which said magnetic circuit (6) is open, the intensity of the holding magnetic force being reduced compared to the closed position.
2. Magnetic actuator (1) according to claim 1, characterized in that it further comprises a return means (8), generating a return force contributing to positioning the magnetic core (2) in a second extreme position, or to maintaining the magnetic core (2) in the second extreme position.
3. Magnetic actuator (1) according to claims 1 and 2, characterized in that the two extreme positions of the magnetic core (2) are stable in the absence of energy injected from outside into the magnetic actuator (1).
4. Magnetic actuator (1) according to any one of claims 1 to 3, characterized in that the housing (5) is configured to form at least two magnetic circuit sections (6), each section forming with at least the magnetic core (2), when in its first extreme position, a distinct magnetic circuit (6), said carcass (5) then comprising a moving section (7) for each magnetic circuit (6), the mechanical controls of each moving section (7) being synchronized so that the moving sections are all open or closed at the same time.
5. Magnetic actuator (1) according to any one of claims 1 to 4, characterized in that at least one moving section (7) is configured so that when its passage from the closed position to the open position is initiated, the magnetic field lines running through the air gap generated by this movement between the moving section (7) and the rest of the frame (5) have, with the direction of movement of the moving section (7) at the level of this air gap, an angle greater than or equal to 60°.
6. Magnetic actuator (1) according to any one of claims 1 to 5, characterized in that the magnetic excitation source comprises at least one permanent magnet (9), generating a magnetic force contributing to maintaining the magnetic core (2) in the first extreme position and / or in the second extreme position, said permanent magnet (9) constituting a segment of the magnetic circuit (6) formed by at least the casing (5) and the magnetic core (2) when it is in its first extreme position.
7. Magnetic actuator (1) according to claim 6, characterized in that at least one moving section (7) is configured so that when its passage from the closed position to the open position is initiated, at least a part of the moving section (7), located in the vicinity of an air gap generated by this movement between the moving section (7) and the rest of the frame (5), approaches the permanent magnet (9), the magnetic force generated by the permanent magnet (9) contributing to promoting this movement.
8. Magnetic actuator (1) according to any one of claims 5 to 7, characterized in that at least one of said at least one permanent magnet (9) is integral with the magnetic core (2), and follows the magnetic core (2) in its displacements between the two extreme positions.
9. Magnetic actuator (1) according to any one of claims 1 to 8, characterized in that the transition of said at least one moving section (7) from the closed position to the open position and vice versa is effected by a rotational movement, about an axis of rotation orthogonal to the axis of translation (3), the axes of rotation and translation (3) being non-intersecting.
10. Magnetic actuator (1) according to any one of claims 1 to 8, characterized in that the passage of said at least one moving section (7) from the closed position to the open position and vice versa is done by a translational movement, along a translational axis parallel to the translational axis (3).
11. Magnetic actuator (1) according to claim 9 and any one of claims 5 to 8, characterized in that the permanent magnet (9) has a cylindrical shape, said moving section (7) having at its end closest to the permanent magnet (9), at the level where an air gap is generated during the opening movement of the moving section (7), a contour comprising two sides and a center, the sides being further from the axis of the cylinder of the permanent magnet (9), and more extended along this axis, than the center, when the moving section (7) is in the closed position.
12. Magnetic actuator (1) according to any one of claims 1 to 11, characterized in that it comprises a manual actuation means enabling said at least one movable section (7) to be moved from the closed position to the open position and vice versa.
13. Magnetic actuator (1) according to any one of claims 1 to 12, characterized in that the magnetic excitation source comprises at least one pilot coil (4), comprising at least one winding arranged around at least one section of the magnetic circuit (6), the pilot coil (4) being configured to be able to carry an electric current, the magnetic flux generated by the pilot coil (4) being able to be driven to move the magnetic core (2) from one extreme position to the other.
14. Magnetic actuator (1) according to claim 13, characterized in that said at least one pilot coil (4) comprises at least one winding arranged around the translation axis (3), around at least one section of said magnetic core (2).
15. A method for disengaging a magnetic actuator (1) according to any one of claims 1 to 14, comprising the following steps: - using the magnetic actuator (1), wherein at least one moving section (7) is in the closed position, the magnetic flux generated by the magnetic excitation source and flowing through the magnetic circuit (6) allowing, at least in certain configurations of the magnetic core (2) and / or the magnetic excitation source, to maintain the magnetic core (2) in at least one of its extreme positions with a holding magnetic force, - putting said at least one movable section (7) into an open position, the intensity of the holding magnetic force then being reduced compared to the closed position.
16. Electrical switching device (12) of an electrical circuit comprising at least one fixed contact (13) and at least one moving contact (14), said at least one moving contact (14) being movable between at least one engaged position in which said at least one moving contact (14) is in contact with said at least one fixed contact (13) and the electrical circuit is closed, and an un-engaged position in which said at least one moving contact (14) is not in contact with said at least one fixed contact and the electrical circuit is open, said switching device (12) being characterized in that it further comprises a magnetic actuator (1) according to any one of claims 1 to 14, and in that the movements of the moving contact (14) are controlled by said magnetic actuator (1).