EP2412901B1 - Electronic lock - Google Patents

Description

The invention relates to an electronic lock.

• un stator et un rotor monté à rotation dans le stator et muni d'un canal dans lequel la clé peut être introduite,
• un organe de blocage du rotor déplaçable dans un logement du stator entre une position de blocage dans laquelle il est en prise avec le rotor pour bloquer sa rotation et une position escamotée dans laquelle il libère la rotation du rotor, et
• un levier de verrouillage déplaçable, en réponse à un ordre de déverrouillage électrique, entre une position de verrouillage dans laquelle le levier de verrouillage est susceptible d'être immobilisé par l'organe de blocage pour s'opposer à son déplacement à partir de sa position de blocage et une position de déverrouillage dans laquelle l'organe de blocage est libre de quitter sa position de blocage.

The applicant knows electronic locks, intended to be controlled by a key comprising electronic means for controlling the electric unlocking of the lock. These locks include:

• a stator and a rotor rotatably mounted in the stator and provided with a channel into which the key can be inserted,
• a rotor locking member movable in a stator housing between a locking position in which it engages the rotor to block its rotation and a retracted position in which it releases the rotation of the rotor, and
• a movable locking lever, in response to an electric unlocking command, between a locking position in which the locking lever can be immobilized by the locking member to oppose its displacement from its position blocking and an unlocking position in which the locking member is free to leave its locking position.

An example of such a type of lock is for example disclosed in the patent application FR 2 849 083 .

When a suitable key is inserted into the channel and then turned, a force is exerted on the rotor locking member to move the member from its locking position to its retracted position. In parallel with the exercise of this force, an electric unlock command is generated, for example following the verification of a digital code contained in the key. In response to this electrical unlocking command, the locking lever is moved so as to allow movement of the locking member to its retracted position. However, it is possible that the electrical unlocking command occurs after the key has exerted its force on the locking member. In this case, it is common for the locking lever to become stuck. Also, when the unlock command is generated, the lock lever can not be moved and, therefore, the lock does not unlock. In order to overcome this drawback, locks known to the applicant furthermore comprise a storage arm made of magnetic material able to rotate about an axis between a rest position and a storage position, in response to the unlocking command. electric, even if the locking lever is immobilized by the locking member.

An example of such a type of lock is for example disclosed in the patent application US 2002/0189307 . In this application, a storage arm moves from its home position to its storage position regardless of whether the lock lever is locked or not. Still in this application, a torsion spring mechanically links the locking lever to the storage arm. When the lever is immobilized but an unlock command is generated, the storage arm moves to its storage position and mechanically memorizes the unlock command. Then, when the lever decouples, the torsion spring exerts a restoring force on the unlocking lever which tilts in its unlocking position. The use of this torsion spring increases the size of the lock.

Furthermore, the movement of the storage arm from its rest position to its storage position is achieved by means of an electric motor arranged parallel to the axis of rotation of the rotor. Such an arrangement of the electric motor also inevitably increases the size of this lock. Finally, the power consumption of such a lock is important.

From the state of the art is also known from US2002 / 189307A1 and of DE3902992C1 .

The invention aims to remedy one or more of these disadvantages.

• la serrure comporte au moins un aimant fixé sur le stator ou le bras de mémorisation pour déplacer le bras de mémorisation de sa position de repos vers sa position de mémorisation,
• l'un du stator et du bras de mémorisation comporte un arceau en matériau magnétique et l'autre du stator et du bras comporte une dent magnétique en vis-à-vis de l'arceau de manière à créer un premier entrefer par l'intermédiaire duquel se reboucle un premier circuit magnétique qui relie deux pôles opposés de l'aimant, la dent et l'arceau étant conformés de manière à ce que :
  • l'épaisseur du premier entrefer diminue au fur et à mesure que le bras de mémorisation tourne de sa position de repos vers sa position de mémorisation, et/ou
  • la surface des faces de l'arceau et de la dent en vis-à-vis augmente, dans une direction parallèle à l'axe de rotation du bras, au fur et à mesure que le bras tourne de sa position de repos vers sa position de mémorisation.

The invention relates to a lock in which:

• the lock comprises at least one magnet fixed on the stator or the storage arm to move the storage arm from its rest position to its storage position,
• one of the stator and the storage arm has a hoop of magnetic material and the other of the stator and the arm has a magnetic tooth vis-à-vis the hoop so as to create a first air gap via which is looped a first magnetic circuit that connects two opposite poles of the magnet, the tooth and the arch being shaped so that:
  • the thickness of the first air gap decreases as the storage arm rotates from its rest position to its storage position, and / or
  • the surface of the faces of the hoop and the tooth facing each other increases, in a direction parallel to the axis of rotation of the arm, as the arm rotates from its rest position to its position memorisation.

In the lock above, the stator and the storage arm are shaped so that the storage arm moves from its rest position to its storage position with zero power consumption and optimized space.

• ■ le stator comporte également un doigt en matériau magnétique créant un deuxième circuit magnétique reliant les deux pôles opposés du même aimant en passant par l'intermédiaire du bras de mémorisation et d'un second entrefer entre le bras de mémorisation et une extrémité du doigt, le bras de mémorisation et l'extrémité du doigt étant conformés de manière à ce que le réluctance du deuxième entrefer soit inférieure à celle du premier entrefer lorsque le bras de mémorisation est dans sa position de repos,
• ■ l'organe de blocage comporte une pièce magnétique créant un troisième circuit magnétique qui relie les deux pôles opposés du même aimant en passant par l'intermédiaire du bras de mémorisation et d'un troisième entrefer entre le bras et la pièce magnétique de l'organe de blocage, le bras de mémorisation et la pièce magnétique étant conformés de manière à ce que la réluctance du troisième entrefer soit inférieure à celle du premier entrefer lorsque le bras de mémorisation est dans sa position de mémorisation,
• ■ la serrure comporte une source de champ magnétique commandable apte à réduire suffisamment le flux du champ magnétique à l'intérieur du doigt en matériau magnétique pour que l'intensité du champ magnétique dans le deuxième entrefer soit inférieure à l'intensité du champ magnétique dans le premier entrefer de manière à déclencher la rotation du bras de mémorisation de sa position de repos vers sa position de mémorisation, en réponse à l'ordre de déverrouillage,
• ■ le levier de verrouillage est réalisé en matériau magnétique et est conformé de manière à ce que l'aimant permanent sollicite en permanence le levier vers sa position de déverrouillage,
• ■ le bras de mémorisation comporte une butée apte à maintenir le levier de verrouillage en position de verrouillage à l'encontre de la sollicitation exercée par l'aimant permanent lorsque le bras de mémorisation est dans sa position de repos,
• ■ en tout point S de la face de l'arceau en vis-à-vis de la dent magnétique, le centre du cercle osculateur en ce point S se situe toujours d'un même côté d'un plan contenant l'axe de rotation du bras de mémorisation et ce point S,
• ■ l'arceau s'étend sur une portion angulaire supérieure ou égal à 10 degrés,
• ■ le bras est en appui contre un butoir lorsque le bras est dans sa position de repos et/ou le bras est en appui contre un talon de l'organe de blocage lorsque le bras est en position de mémorisation, et
• ■ l'aimant et le bras forment un quatrième entrefer, le bras et l'aimant étant conformés de manière à ce que l'épaisseur de l'entrefer diminue à mesure que le bras se déplace de sa position de repos à sa position de mémorisation.

The embodiments of this lock may further comprise one or more of the following features:

• The stator also comprises a finger made of magnetic material creating a second magnetic circuit connecting the two opposite poles of the same magnet via the storage arm and a second air gap between the storage arm and one end of the finger, the storage arm and the end of the finger being shaped so that the reluctance of the second air gap is lower than that of the first air gap when the storage arm is in its position of rest,
• The locking member comprises a magnetic part creating a third magnetic circuit which connects the two opposite poles of the same magnet via the storage arm and a third gap between the arm and the magnetic part of the locking member, the storage arm and the magnetic part being shaped so that the reluctance of the third air gap is lower than that of the first gap when the storage arm is in its storage position,
• The lock comprises a controllable magnetic field source capable of sufficiently reducing the flux of the magnetic field inside the finger of magnetic material so that the intensity of the magnetic field in the second air gap is less than the intensity of the magnetic field in the first air gap so as to trigger the rotation of the storage arm from its rest position to its storage position, in response to the unlock command,
• The locking lever is made of magnetic material and is shaped in such a way that the permanent magnet constantly urges the lever towards its unlocked position,
• The storage arm comprises a stop capable of holding the locking lever in the locked position against the bias exerted by the permanent magnet when the storage arm is in its rest position,
• ■ at any point S of the face of the arch opposite the magnetic tooth, the center of the osculating circle at this point S is always on the same side of a plane containing the axis of rotation of the storage arm and this point S,
• The arch extends over an angular portion greater than or equal to 10 degrees,
• The arm bears against a stopper when the arm is in its rest position and / or the arm bears against a heel of the locking member when the arm is in the storage position, and
• The magnet and the arm form a fourth air gap, the arm and the magnet being shaped so that the thickness of the air gap decreases as the arm moves from its rest position to its storage position .

• ■ le bras de mémorisation est maintenu dans sa position de repos sans consommation électrique par le biais du deuxième entrefer et du même aimant,
• ■ le bras de mémorisation est maintenu dans sa position de mémorisation sans consommation électrique par le biais du troisième entrefer et du même aimant,
• ■ la source de champ magnétique, typiquement une bobine, permet de déclencher la rotation à l'aide d'une simple impulsion de courant et permet donc de minimiser la consommation électrique,
• ■ réaliser le levier de verrouillage en matériau magnétique permet de déplacer le levier de verrouillage vers sa position de déverrouillage sans ressort de torsion et sans consommation électrique,
• ■ l'utilisation d'une butée sur le bras de mémorisation permet de maintenir le levier de verrouillage en position de verrouillage sans ajouter d'aimant et permet donc de limiter l'encombrement de la serrure,
• ■ placer le centre du cercle osculateur toujours du même côté du plan permet d'augmenter le moment exercé par la force magnétique de l'aimant pour faire tourner le bras de mémorisation,
• ■ utiliser un butoir ou un talon renforce la stabilité de la position du bras de mémorisation dans sa position de repos ou dans sa position de mémorisation, et
• ■ diminuer l'épaisseur du quatrième entrefer lors du déplacement du bras de mémorisation permet de minimiser la consommation électrique de la serrure.

The embodiments of this lock also have the following advantages:

• The storage arm is held in its rest position without electrical consumption by means of the second air gap and the same magnet,
• The storage arm is held in its storage position without power consumption via the third air gap and the same magnet,
• The magnetic field source, typically a coil, makes it possible to trigger the rotation by means of a simple current pulse and thus makes it possible to minimize the power consumption,
• ■ the locking lever made of magnetic material moves the locking lever to its unlocking position without torsion spring and without power consumption,
• The use of a stop on the storage arm makes it possible to keep the locking lever in the locking position without adding a magnet and thus makes it possible to limit the size of the lock,
• Placing the center of the osculator circle always on the same side of the plane makes it possible to increase the moment exerted by the magnetic force of the magnet to rotate the storage arm,
• Using a stopper or a heel enhances the stability of the position of the storage arm in its rest position or in its storage position, and
• ■ Decrease the thickness of the fourth gap when moving the storage arm to minimize the power consumption of the lock.

• la figure 1 est une illustration schématique d'une serrure électronique,
• la figure 2 est une illustration schématique en perspective d'un mécanisme de verrouillage électrique de la serrure de la figure 1,
• la figure 3 est une illustration schématique en vue de derrière du mécanisme de verrouillage de la figure 2
• la figure 4 est une illustration schématique en coupe d'un levier de verrouillage pour le mécanisme de la figure 2,
• la figure 5 est une illustration schématique en vue de face d'un bras de mémorisation pour le mécanisme de la figure 2,
• la figure 6 est une illustration schématique partielle du mécanisme de verrouillage de la figure 2 lorsque le bras de mémorisation est en position de repos,
• la figure 7 est une illustration schématique partielle du mécanisme de la figure 2 lorsque le bras de mémorisation se déplace de sa position de repos vers sa position de mémorisation,
• la figure 8 est une illustration schématique partielle du mécanisme de la figure 2 lorsque le bras de mémorisation est en position de mémorisation,
• la figure 9 est un organigramme d'un procédé de fonctionnement de la serrure de la figure 1,
• la figure 10 illustre une première variante du mécanisme la figure 2,
• la figure 11 illustre une deuxième variante du mécanisme de la figure 2, et
• la figure 12 illustre une troisième variante du mécanisme la figure 2.

The invention will be better understood on reading the description which follows, given solely by way of nonlimiting example and with reference to the drawings in which:

• the figure 1 is a schematic illustration of an electronic lock,
• the figure 2 is a schematic perspective illustration of an electric lock mechanism of the lock of the figure 1 ,
• the figure 3 is a schematic illustration in the back view of the locking mechanism of the figure 2
• the figure 4 is a schematic sectional illustration of a locking lever for the mechanism of the figure 2 ,
• the figure 5 is a schematic illustration in front view of a storage arm for the mechanism of the figure 2 ,
• the figure 6 is a partial schematic illustration of the locking mechanism of the figure 2 when the storage arm is in the rest position,
• the figure 7 is a partial schematic illustration of the mechanism of the figure 2 when the storage arm moves from its rest position to its storage position,
• the figure 8 is a partial schematic illustration of the mechanism of the figure 2 when the storage arm is in the storage position,
• the figure 9 is a flowchart of a method of operation of the lock of the figure 1 ,
• the figure 10 illustrates a first variant of the mechanism figure 2 ,
• the figure 11 illustrates a second variant of the mechanism of the figure 2 , and
• the figure 12 illustrates a third variant of the mechanism figure 2 .

In these figures the same references are used to designate the same elements.

In the remainder of this description, the features and functions well known to those skilled in the art are not described in detail.

The figure 1 represents a barrel 2 of a double barrel lock whose other barrel is not shown in the figure 1 . This barrel 2 extends in depth along a direction Z perpendicular to horizontal and vertical directions, respectively X and Y. In the remainder of the description, the terms "lower" and "upper" are defined with reference to the direction Y.

The two barrels are housed in a conventional manner in a door (not shown) and are arranged symmetrically with respect to the average plane P of the door. The two barrels are positioned and connected in a conventional manner to one another by a connecting rod (not shown) which has in its middle a bulge serving as a spacer to maintain a predefined spacing between the two barrels. In the space between the two barrels is arranged, conventionally, a bit (not shown) which can be rotated by a rotor 4 of one or the other of the two barrels when an appropriate key, for example a key 5 is introduced into a channel 6 of the rotor 4 and manually rotated by a user.

When rotated by the key 5 and the rotor 4, the bit controls a conventional lock mechanism (not shown) which causes the displacement of at least one bolt of the lock in a direction allowing the opening of the lock. door or in a direction prohibiting the opening of the door according to the direction of rotation of the key 5.

The rotor 4 of the barrel 2 is rotatably mounted in a profiled stator 7. The stator 7 is itself housed in an outer sheath 8 having the same profile. In the example, the stator 7 has a standardized profile, called "European". Still in the example, the axis of rotation of the rotor 4 is parallel to the direction Z.

The barrel 2 conventionally comprises several pairs of stator and rotor pins, which are arranged in pairs, end to end, in corresponding pairs of aligned housings respectively formed in the stator 7 and in the rotor 4. arrangement of the rotor and stator pins is well known, this one has not been shown to simplify the figure 1 .

The key 5, which has for example a substantially rectangular cross section, has on at least one of its two large faces, preferably on its two large faces, indentations and / or reliefs which cooperate with the rotor pins. The imprints and / or the reliefs are shaped and the lengths of the rotor pins are chosen so that, if a good key 5 is inserted into the channel 6 of the rotor 4, the interface between each rotor pin and the pin of associated stator is located exactly at the interface between the rotor 4 and the stator 7. Under these conditions, the rotor 4 can be rotated manually using the key 5, provided that a mechanism 9 electric lock is him - even in an unlocked state.

Indeed, the barrel 2 comprises an additional locking member 10 for preventing the rotor 4 from rotating as a suitable digital code contained in a memory (not shown) housed in the key 5 has not been introduced into a circuit 12 housed in the barrel 2 (on the figure 1 the circuit 12 is disposed outside the barrel 2 to simplify the drawings). This circuit 12, when it receives the appropriate code, generates an electric unlock command. For example, it controls the mechanism 9 to enable the unlocking of the rotor 4.

For example, the code is transmitted from the key 5 to the electronic circuit 12 of the lock via radio relay or via electrical contacts. For transmission by radio, preferably, the key 5 is equipped with a transponder and the circuit 12 is equipped with a transponder reader.

When the key 5 is inserted into the channel 6 of the rotor 4, the digital code contained in the memory of the key 5 is transmitted to the circuit 12. For example, the circuit 12 then compares the transmitted code with at least one prerecorded code in a memory. In case of agreement between the two codes, the circuit 12 generates the electric unlocking command of the mechanism 9.

In the embodiment of the lock shown in the drawings, the additional locking member 10 is a stator pin which cooperates with a corresponding rotor pin 18 so that if the correct key is inserted into the channel 6, the interface between these two pins is exactly at the interface of the stator 7 and the rotor 4. However, unlike the other stator pins, the locking member 10 is extended by a conical stud 20, with rounded apex, which is engaged in a corresponding frustoconical recess 22 formed in the rotor pin 18. In the example, the member 10 is made of a magnetic material.

In this description, the term "magnetic material" denotes a material whose relative magnetic permeability is strictly greater than 1 and, preferably, greater than 100 or 1000. For example, the material is a ferromagnetic material such as steel.

The member 10 is movable between a locking position (represented on the figure 1 ) in which it is engaged with the rotor 4 to block its rotation and a retracted position in which it releases the rotation of the rotor 4. For this purpose, the member 10 is slidably mounted in a cylindrical housing 24 which is formed in the stator 7 and which is aligned axially with a housing 26 in the rotor 4 in which slides the pin 18 of the rotor. The member 10 further comprises a transverse bar 28 which is formed integrally with the member 10 at the lower end thereof. One end of the bar 28 is shaped to form a heel 29. Advantageously, the two sides of the bar 28 are engaged and guided in slots (not shown) formed in the wall of the housing 24. These slots prevent the body locking 10 to rotate when it moves in the cylindrical housing 24.

Mechanism 9 will now be described in more detail with reference to figures 2 and 3 .

The mechanism 9 comprises a cavity 32. The cavity 32 is a recessed zone disposed inside the stator 7. In the example, the cavity 32 is located below the housing 24 and receives the bar 28.

The mechanism 9 comprises a spring 50 adapted to bias the member 10 towards its locking position when the housings 24 and 26 are in facing relation. This spring 50 rests, at its lower end, against the bottom of the cavity 32 and at its upper end against the underside of the heel 29 of the member 10.

The mechanism 9 also comprises a permanent magnet 30 able to radiate a magnetic field. The magnet 30 is housed in a compartment of the stator 7 provided for this purpose. In the example, the magnet 30 is disposed on a support 33 delimiting the lower periphery and the left side of the cavity 32. This support 33 is made of a magnetic material, preferably ferromagnetic, so as to channel the flow of the field Magnet radiated by the magnet 30. In the example, the support 33 has a bend from which extends a horizontal finger 33a and a vertical tooth 33b.

The finger 33a extends horizontally at the bottom of the cavity 32. The distal end of this finger 33a forms a stopper 40, also of magnetic material, preferably ferromagnetic, which extends vertically. The stopper 40 is described in more detail with reference to the figure 6 .

The tooth 33b extends vertically from the bottom of the cavity 32 to the bar 28. Here, the cross section of the tooth 33a flares away from its free end towards the bend.

The magnet 30 is disposed inside the bend of the support 33.

The mechanism 9 comprises a controllable source 52 of magnetic field capable of reducing or canceling the magnetic field flux of the magnet 30 in the finger 33a. In the example, the source 52 is a coil wound around the finger 33a.

• une position de verrouillage dans laquelle le levier 34 est susceptible d'être immobilisé par l'organe 10 de blocage pour s'opposer à son déplacement, et
• une position de déverrouillage dans laquelle l'organe 10 de blocage est libre de quitter sa position de blocage.

The mechanism 9 also comprises a locking lever 34 movable between:

• a locking position in which the lever 34 can be immobilized by the locking member 10 to oppose its movement, and
• an unlocking position in which the locking member 10 is free to leave its locking position.

The lever 34 is disposed in the cavity 32. Here, the lever 34 is in the locking position when the lever 34 is vertical, that is to say it extends mainly along the Y direction. 34 is in the unlocking position when it extends in an oblique direction belonging to the plane formed by the X and Y directions. figures 2 and 3 the lever 34 is in the locking position.

Here, the movement of the lever 34 from its locking position to its unlocking position is achieved by rotation of the lever 34 in the clockwise direction. For this purpose, the lever 34 is rotatably mounted on an axis 36. The axis 36 is parallel to the direction Z.

The lever 34 is shaped so that when in the locking position, a game 37a (visible on the figure 3 ) remains between the lever 34 and the bar 28. This clearance 37a is large enough to allow the lever 34 to rotate from its locking position to its unlocked position. However, as explained above, when the lever 34 is in the locking position and the key 5 is inserted into the channel 6 and rotated, the rotor 4 exerts a force on the member 10 pushing the member 10 to its retracted position. The member 10 is slightly moved down. The clearance 37a then vanishes and the movement of the member 10 towards its retracted position is prevented. When the clearance 37a is zero, the lever 34 is immobilized.

Furthermore, in this example when the member 10 is moved downwards and the clearance 37a vanishes, the member 10 exerts on the lever 34 a force urging the lever 34 towards the bottom of the cavity 32. This force elastically deforms the axis 36 so that a lower end of the lever 34 abuts against the bottom of the cavity 32. Thus, when the clearance 37a vanishes, the lever 34 is immobilized between the member 10 and the bottom of the cavity 32.

Once the member 10 stops exerting the force urging the lever 34 towards the bottom of the cavity 32 (for example if the member 10 returns from its retracted position to its locking position), the axis 36, by inverse elastic deformation returns to its initial position in which the lever 34 is not in abutment at the bottom of the cavity 32.

The shape of the lever 34 is described in more detail with reference to the figure 4

• une position de repos, et
• une position de mémorisation, en réponse à l'ordre de déverrouillage électrique.

The mechanism 9 also comprises a storage arm 38 able to memorize an electric unlocking command even if the lever 34 is immobilized by the member 10. The arm 38 can be moved between:

• a rest position, and
• a storage position, in response to the electrical unlock command.

Here, the arm 38 is in the rest position when it extends substantially vertically. In the rest position, one end of the arm 38 bears on the stopper 40. The arm 38 is in the storage position when an upper end 39 of the arm 38 abuts against the heel 29. figures 2 and 3 , the arm is in the rest position.

The arm 38 is disposed inside the cavity 32. Here, the arm 38 is mounted free to rotate on the axis 36. The movement of the arm 38 from its rest position to its storage position is effected by a clockwise rotation.

The arm 38 is shaped so that, when the arm 38 is in its rest position, a game 37b (visible on the figure 2 ) separates the bar 28 from the upper end 39. This clearance 37b is larger than the clearance 37a so that even when the lever 34 is blocked by the bar 28 (and therefore the clearance 37a is zero), the game 37b is non-zero. The arm 38 can therefore always move to memorize the unlocking order regardless of whether the lever 34 is immobilized or not.

The arm 38 is made of a magnetic material, preferably ferromagnetic, so as to be displaceable by magnetic forces which create a moment of rotation of the arm 38 about the axis 36. The directions and intensities of the magnetic forces which exert on the arm 38 depend in particular on the shape and the thickness of the air gaps between the arm 38 and the magnetic parts in the vicinity. The arm 38 is described in more detail with reference to the figure 5 .

Lever 34 will now be described in more detail with reference to the figure 4 . This figure is a sectional view along a sectional plane passing through the lever 34 and the magnet 30. The lever 34 is made of a magnetic material, preferably ferromagnetic. The magnet 30 and the lever 34 are arranged facing each other so that the magnet 30 constantly urges the lever 34 towards its unlocked position. The portion of the lever 34 facing the magnet 30 and the magnet 30 form an air gap 341.

In this description, the term "air gap" means the space, typically filled with air, which separates two magnetic pieces vis-à-vis and through which the field lines of a magnetic circuit are looped. Moreover, here, the "zone of contact" between the two moving magnetic parts with respect to each other is also referred to as "air gap" when they have come into mechanical contact with one another as a result of their displacement.

où,

• R est la réluctance de l'entrefer,
• E est l'épaisseur de l'entrefer,
• µ ₀ est la perméabilité du vide, et
• S est la section transversale des faces en vis-à-vis de chaque côté de l'entrefer.

The lever 34 tends to position itself with the magnet 30 so that the reluctance of the gap 341 is as small as possible. In order to further increase the bias of the lever 34 towards its unlocking position, the lever 34 is shaped so that the reluctance of the gap 341 decreases as the lever 34 rotates from its locking position to its position of unlocking. The reluctance of an air gap is defined using the following relation: $$\mathit{R}\mathit{=}\mathit{E}\mathit{/}\left({\mathit{<figure-callout\; id="0"\; label="\mu "\; filenames="imgf0001.png"\; state="\{\{state\}\}">\mu </figure-callout>}}_{\mathit{0}}\mathit{.}S\right)$$

or,

• R is the reluctance of the air gap,
• E is the thickness of the gap,
• μ ₀ is the permeability of the vacuum, and
• S is the cross section of the faces vis-à-vis each side of the gap.

Here, the lever 34 is shaped so that the thickness E of the gap 341 decreases as the lever 34 rotates. For this purpose, the lower end of the lever 34 forms a foot 342 comprising a bevel 346 vis-à-vis the magnet 30. The bevel 346 is inclined so that the distance between the bevel 346 and the magnet 30 decreases as lever 34 rotates clockwise. In the example, the reluctance of the gap 341 is minimum when the lever 34 is in the unlocking position.

The lever 34 also comprises a flat 348 disposed on an upper end 350 of the lever 34. This flat 348 forms a stop for the bar 28 opposing the displacement of the member 10 when the lever 34 is in the locking position and the member 10 moves from its locking position to its retracted position.

The lever 34 further comprises a pin 352 for repositioning the lever 34 which extends from the foot 342 in the direction Z.

The arm 38 will now be described in more detail with reference to the figure 5 .

• un entrefer 45 entre l'aimant 30 et la face en vis-à-vis de l'arceau 42,
• l'arceau 42,
• l'entrefer 44, puis
• la dent 33b pour se reboucler sur l'aimant 30.

The arm 38 has a hoop 42 which extends from a lower end of this arm 38. The hoop 42 and the tooth 33b form an air gap 44 through which loops a magnetic circuit C1 connecting the two opposite poles of the magnet 30. The magnetic circuit C1 exerts a magnetic force F1 on the arm 38. This circuit C1 passes successively by:

• an air gap 45 between the magnet 30 and the face vis-à-vis the hoop 42,
• the arch 42,
• the gap 44 and then
• the tooth 33b to bounce back on the magnet 30.

To simplify the figures, the magnetic circuits presented in this description are illustrated for each one in a single figure. However, these Magnetic circuits exist in all the positions shown in the figures and vary according to the position of the arm 38 and the lever 34. Moreover, still for the purpose of simplifying the figures, only the predominant magnetic circuits have been shown. However, an infinity of magnetic circuits are looped inside the described lock.

The arch 42 is shaped so that the reluctance of the gap 44 decreases as the arm 38 moves from its rest position to its storage position. Here, the shape of the arch 42 is such that the thickness of the air gap 44 decreases as the arm 38 rotates from its rest position to its storage position. Under these conditions, the arm 38 is biased by the magnet 30 to its storage position without energy consumption.

In the example, the arch 42 has a concave face 420 vis-à-vis the magnet 30 and the tooth 33b. The profile of the face 420 may be approximated, at first approach, by an arc which extends over an angular portion greater than or equal to 10 degrees and, preferably, greater than or equal to 20, 30, or 40 degrees. The position of this arc is, for example, adjusted by the least squares method to minimize the differences between this arc and the actual profile of the face 420. In the example described, the profile of the face 420 It is not strictly an arc since its free end is slightly curved inwards.

In this example, the arm 38 is shaped so that at any point S of the face 420, the center 422 of the osculating circle 424 at this point S is always on the same side of a plane 426 containing the axis 36 and the point S. Preferably, the center 422 does not belong to the plane 426 and is below it in this example. Under these conditions, the force F1 creates a moment M which can move the arm 38 from its rest position to its storage position. In the description, the term "moment of a magnetic force" designates the moment of the magnetic force capable of pivoting the arm 38 about the axis 36. A condition for a magnetic force exerting a moment on the arm 38 is that this force is directed in a non-intersecting direction with the axis 36.

In the illustrated example, the arm 38 is advantageously shaped so that the thickness of the air gap 45 also decreases as the arm 38 moves from its rest position to its storage position.

The arm 38 further comprises a stop 51 adapted to hold the lever 34 in the locking position against the bias exerted by the magnet 30 when the arm 38 is in the rest position. In the example, the stop 51 is a projection disposed on the arch 42. Here, the stop 51 extends radially on the inner radius of the arch 42. When the arm 38 is in the rest position, the stop 51 maintains the lever 34 in the locking position via the stud 352 disposed on the lever 34.

The figure 6 represents the arm 38 in its rest position. In the rest position, a rear end 41 of the arch 42 is in abutment against the stopper 40. The stopper 40 prevents the rotation of the arm 38 in the opposite direction of clockwise. Advantageously, the stopper 40 is beveled so as to maximize the magnetic force exerted between the stopper 40 and the end 41.

The stopper 40 forms with the end 41 an air gap 46 through which loops a magnetic circuit C2 connecting the two opposite poles of the magnet 30. This magnetic circuit C2 passes successively through the finger 33a, the gap 41, the arch 42 and the gap 45. The reluctance of the gap 46 is minimized when the arm 38 is in the rest position. The arm 38 and the support 33 are shaped so that when the arm 38 is in the rest position, the reluctance of the gap 46 is less than the reluctance of the gap 44.

F2 denotes the magnetic force exerted by the magnetic circuit C2 on the arm 38.

The figure 7 represents the arm 38 turning from its rest position to its storage position. In this position, the reluctance of the gap 44 is smaller than the reluctance of the gap 46.

The figure 8 represents the arm 38 in the storage position. In this position, the upper end 39 of the arm 38 and the heel 29 form an air gap 48 through which loops a third magnetic circuit C3 which connects the two opposite poles of the magnet 30. This circuit C3 passes successively through the gap 45, the arch 42, the arm 36, the gap 45, the bar 28 and the tooth 33b. Advantageously, the end 39 and the heel 29 are shaped so that when the arm 38 is in its storage position, the reluctance of the gap 48 is less than the reluctance of the gaps 44 and 46. For this purpose, in this embodiment, the end 39 is in abutment against the heel 29 when the arm 38 is in its storage position.

F3 denotes the magnetic force exerted by the magnetic circuit C3 on the arm 38.

The operation of the lock will now be presented with reference to the figure 9 .

In a preliminary step, the lock is in a locked state. In this locked state, the housings 24 and 26 are vis-à-vis and the member 10 is in its blocking position. The arm 38 is in the rest position ( figure 6 ). When the arm 38 is in the rest position, the gap 46 being thinner than the air gaps 44 and 48, the moment of the magnetic force F2 is stronger than the moment of the magnetic forces F1 and F3. Moreover, this moment of the magnetic force F2 urges the arm 38 counter-clockwise. The arm 38 is thus held against the stopper 40.

In addition, the lever 34 is held in its locking position via the stop 51 and the stud 352.

In a step 62, a user enters the key 5 in the channel 6 of the lock. The circuit 12 reads the digital code carried by the key 5. If this digital code is wrong, the mechanism 9 remains in the locked state. Thus, when the user tries to turn the rotor 4, the member 10 sinks into the housing 24 until the clearance 37a vanishes. The member 10 is then in abutment against the lever 34. The member 10 can not reach its retracted position, the rotor 4 can not rotate and the lock remains in the locked state. The lock therefore returns to step 60.

If the digital code carried by the key is correct, an unlocking command of the mechanism 9 is generated during a step 64.

During this step 64, in response to the unlocking command, an electric pulse is generated at the terminals of the source 52. The source 52 then radiates an electromagnetic field that is withdrawn from the permanent magnetic field of the magnet 30 in the finger 33a. . Here, the source 52 cancels the flux of the magnetic field in the finger 33a. Thus, the intensity of the magnetic flux in the gap 46 becomes less than the intensity of the magnetic flux in the gap 44. Under these conditions, the moment of the magnetic force F1 becomes stronger than that of the force F2. The moment of the magnetic force F1 then triggers the movement of the arm 38 from its rest position to its storage position ( figure 7 ). Once the rotation of the arm 38 is triggered, the source 52 is no longer energized since the conformation of the arm 38 in the arch allows the arm 38 to turn to its storage position without power consumption. The duration of the pulse is determined so that the supply of the source 52 is completed at a time when the arm 38 has already turned enough so that the moment of the force F1 is stronger than that of the force F2. Thus, despite stopping the supply of the source 52, the arm 38 continues its movement towards its storage position.

The movement of the arm 38 continues until the air gap 48 is less thick than the air gaps 44 and 46. At this moment, the moment of the magnetic force F3 is stronger than the moment of the magnetic force F2. The moment of the force F3 keeps the end 39 of the arm 38 against the heel 29 ( figure 8 ).

Moreover, when the arm 38 leaves its rest position, the projection 51 no longer holds the lever 34 in its locking position via the stud 352. The lever 34 is then unlocked. If the lever 34 is not immobilized by the member 10 at the moment when the unlocking command is generated, the arm 38 is positioned in its storage position as described above and the lever 34 is biased towards its unlocking position by the magnet 30.

If a rotation of the rotor 4 precedes the electric unlocking command, the lever 34 is immobilized by the member 10 at the moment when the unlocking command is generated. Under these conditions, the arm 38 stores the order by positioning itself in its storage position. Once the lever 34 is no longer immobilized, for example because the user puts the key back so that the rotor 4 no longer exerts a force on the member 10, the lever 34 is biased to its unlocking position by the magnet 30. The mechanism 9 is unlocked.

During a step 66, the user rotates the rotor 4 in the stator 7 by means of the key 5. The rotation of the rotor 4 causes the displacement member 10 to move in its retracted position. 10 is no longer blocked by the lever 34. The lock is then unlocked.

In a step 68, the user locks the lock. The user repositioned the rotor 4 in the stator 7 by means of the key 5 so that the housings 24 and 26 are vis-à-vis. The member 10 is then biased by the spring 50 from its retracted position to its locking position. The arm 38 is returned from its storage position to its rest position via the heel 29 which goes up. The lever 34 is returned from its unlocking position to its locking position via the projection 51 and the stud 352. The lock then returns to the locked state.

The figure 10 illustrates a locking mechanism 100 identical to the mechanism 9 except that the support 33 is replaced by a support 102. This support 102 is identical to the support 33 except that the tooth 33b is replaced by a tooth 102b. The arch 42 of the arm 38 and the tooth 102b form an air gap 104. The tooth 102b is shaped so that the surface of the face of the arch 42 vis-à-vis the tooth 102b increases as and when as the arm 38 rotates from its rest position to its storage position. For this purpose, here the cross section of the tooth 102b flares, in the direction Z, from the elbow to the free end of the tooth 102b. With this conformation, the surface of the air gap 104 increases in a direction parallel to the axis of rotation of the arm, and therefore its reluctance decreases, as the arm 38 rotates to its storage position. In this embodiment, it is therefore no longer necessary for the thickness of the gap 104 to decrease as the arm 38 rotates.

The figure 11 illustrates a locking mechanism 80 identical to the locking mechanism 9 with the exception that the magnet 30 is replaced by a permanent magnet 82 disposed on the arch 42. The support 33 is replaced by a support 84 identical to the support 33 with the exception that the tooth 33b is replaced by a tooth 84b. This tooth 84b is shaped so that when the arm 38 moves from its rest position to its storage position the thickness of an air gap 86 formed by the magnet 30 and the tooth 84b vis-à-vis decreases.

The figure 12 illustrates a locking mechanism 90 identical to the locking mechanism 80 except that the storage arm 38 is replaced by a storage arm 92 in which the arch 42 is omitted. In addition, the magnet 82 is replaced by a magnet 95 disposed on an end 93 of the arm 92. Finally, the support 84 is replaced by a support 94 which is shaped so that the face of this support 94 facing the magnet 95 forms a hoop 97.

The hoop 97 is shaped so that when the arm moves from its rest position to its storage position, the thickness of an air gap 99 formed by the magnet 95 and the face of the hoop 97 in vis-à-vis the magnet 95 decreases.

Many other embodiments are possible. For example, it is possible to use several magnets instead of a single permanent magnet to create the magnetic field that moves the arm.

Similarly, another magnet can be added to move the lever.

Other holding mechanisms may be used in addition or in replacement to keep the arm in its rest position and / or in its storage position. For example, magnets or springs may be used.

The foot of the locking lever can be in the form of an arch.

The stator lock member 10 is not necessarily magnetic material. It can be plastic.

Alternatively, the space of the arm 38 between the axis 36 and the inner radius of the arch 42 is full.

Finally, the magnet and the hoop may be shaped so that the thickness of the gap formed by the magnet and the hoop is constant or increases during rotation of the arm to the storage position.

Claims (10)

1. Electronic lock, intended to be controlled by a key comprising electronic means for controlling the unlocking of the lock, the lock comprising:

   - a stator (7) and a rotor (4) mounted to rotate in the stator (7) and provided with a channel (6) into which the key can be introduced,

   - a member (10) for immobilizing the rotor that can be displaced in a housing of the stator between an immobilizing position in which it is engaged with the rotor (4) to immobilize its rotation and a retracted position in which it releases the rotation of the rotor (4),

   - a locking lever (34) that can be displaced, in response to an electric unlocking command, between a locking position in which the locking lever can be immobilized by the immobilizing member (10) to oppose its displacement from its immobilizing position to an unlocking position in which the immobilizing member (10) is free to leave its immobilizing position, and

   - a memorizing arm (38) made of magnetic material capable of turning about an axis (36) between a rest position, and a memorizing position, in response to the electric unlocking command, even if the locking lever (34) is immobilized by the immobilizing member (10),

   characterized in that:

   - the lock comprises at least one magnet (30) fixed onto the stator (7) or the memorizing arm (38) to displace the memorizing arm (38) from its rest position to its memorizing position,

   - one out of the stator (7) and the memorizing arm (38) comprises an arc (42) made of magnetic material and the other out of the stator (7) and the arm (38) comprises a magnetic tooth (33b) facing the arc (42) so as to create a first air gap (44) via which a first magnetic circuit (C1) is looped back, linking two opposite poles of the magnet (30), the tooth (33b) and the arc (42) being configured in such a way that:

   • the thickness of the first air gap (44) decreases as the memorizing arm (38) turns from its rest position to its memorizing position, and/or

   • the surface of the faces of the arc (42) and of the tooth (33b) facing one another increases, in a direction parallel to the axis of rotation of the arm, as the arm (38) turns from its rest position to its memorizing position.
2. Lock according to Claim 1, in which the stator (7) also comprises a finger (33a) made of magnetic material creating a second magnetic circuit (C2) linking the two opposite poles of the same magnet (30) by passing via the memorizing arm (38) and a second air gap (46) between the memorizing arm (38) and an end of the finger (33a), the memorizing arm (38) and the end of the finger (33a) being configured in such a way that the reluctance of the second air gap (46) is less than that of the first air gap (44) when the memorizing arm is in its rest position.
3. Lock according to any one of the preceding claims, in which the immobilizing member (10) comprises a magnetic piece creating a third magnetic circuit (C3) which links the two opposite poles of the same magnet (30) by passing via the memorizing arm (38) and a third air gap (48) between the arm (38) and the magnetic piece of the immobilizing member (10), the memorizing arm (38) and the magnetic piece being configured in such a way that the reluctance of the third air gap (48) is less than that of the first air gap (44) when the memorizing arm (38) is in its memorizing position.
4. Lock according to Claim 2, in which the lock comprises a controllable magnetic field source (52) capable of sufficiently reducing the flux of the magnetic field within the finger (33a) made of magnetic material for the intensity of the magnetic field in the second air gap (46) to be less than the intensity of the magnetic field in the first air gap (44) so as to trigger the rotation of the memorizing arm (38) from its rest position to its memorizing position, in response to the unlocking command.
5. Lock according to any one of the preceding claims, in which the locking lever (34) is made of magnetic material and is configured in such a way that the permanent magnet (30) permanently stresses the lever (34) towards its unlocking position.
6. Lock according to Claim 5, in which the memorizing arm (38) comprises an abutment (51) capable of holding the locking lever (34) in the locking position against the stress exerted by the permanent magnet (30) when the memorizing arm (38) is in its rest position.
7. Lock according to any one of the preceding claims, in which, at any point S of the face (420) of the arc (42) facing the magnetic tooth (33b), the centre of the osculatory circle (424) at this point S is always situated on one and the same side of a plane (426) containing the axis (36) of rotation of the memorizing arm (38) and this point S.
8. Lock according to any one of the preceding claims, in which the arc (42) extends over an angular portion greater than or equal to 10 degrees.
9. Lock according to any one of the preceding claims, in which the arm (38) bears against a buffer (40) when the arm (38) is in its rest position and/or the arm (38) bears against a heel (29) of the immobilizing member (10) when the arm (38) is in the memorizing position.
10. Lock according to any one of the preceding claims, in which the magnet (30) and the arm (38) form a fourth air gap (45), the arm (38) and the magnet (30) being configured in such a way that the thickness of the air gap (45) decreases as the arm (38) is displaced from its rest position to its memorizing position.

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