LOCKING MECHANISM

Description

technical field

[0001] The present invention relates to a locking mechanism for locking against rotation a shaft of a transmission chain of a mobility device, such as a motor vehicle for example. Technological background

[0002] Locking mechanisms are used, for example, as parking brakes to secure a stationary vehicle. In such cases, they prevent the vehicle's drive shaft from rotating. These locking mechanisms are commonly used in vehicles with automatic transmissions, hybrid vehicles, and electric vehicles.

[0003] Locking mechanisms are known, notably from US patent 2018 / 0112774, to include a movable pawl equipped with a locking pin and pivotally mounted on a transmission housing between a released position and a locked position. In the locked position, the locking pin is inserted into a locking recess that is rotationally fixed to the transmission shaft to be locked. The locking mechanism further includes a thrust device guided in translation on the transmission housing and comprising a cam follower that cooperates with a cam surface of the pawl such that a translational movement of the thrust device causes the pawl to pivot between the released and locked positions.

[0004] An actuating lever is used to control the movement of the thrusting device. The actuating lever is pivotally mounted on the transmission housing and driven in rotation, directly or indirectly, by the rotor shaft of an electric motor.

[0005] Most often, the actuating lever has an outer rim with a first and second angular positioning notch. A positioning element fixed to the transmission housing includes an elastic device, for example, a flexible blade, that presses against the outer rim of the actuating lever. The positioning element is configured to engage in the first angular positioning notch when the movable pawl is in the locked position, and in the second angular positioning notch when the movable pawl is in the released position.

[0006] The positioning device thus makes it possible to maintain the position of the locking mechanism in a stable and precise manner in the released position and / or in the locked position.

[0007] Such a structure for the blocking mechanism poses several technical problems: First, the compactness must be improved to accommodate the locking mechanism within the very limited space available in modern transmissions, particularly those for electric vehicles. Second, assembly must be simplified. Specifically, the various components of the locking mechanism can be attached to the transmission housing along non-parallel mounting axes, resulting in a complex assembly process involving several steps. Finally, these improvements in compactness and assembly must be achieved while maintaining sufficient mechanical strength for the positioning element, which is subjected to the mechanical stresses occurring during the vehicle's braking phases. Summary

[0008] Throughout this text, ordinal numeral adjectives are used to differentiate features. They do not define the position of a feature. Therefore, for example, a third feature of a product does not mean that the product has a first and / or a second feature.

[0009] One idea behind the invention is a locking mechanism designed to prevent a vehicle's shaft from rotating.

[0010] An idea underlying the invention is a blocking mechanism that makes it possible to solve one or more technical problems of the prior art, for example the aforementioned problems.

[0011] The invention relates to a locking mechanism suitable for mounting in a transmission housing to prevent rotation of a shaft of a vehicle equipped with at least one locking recess, the locking mechanism comprising: a movable pawl comprising a locking finger, the movable pawl being mounted pivotally about a pivot axis between a locking position in which the locking finger is engaged in the locking recess and a released position in which the locking finger is disengaged from said locking recess, the movable pawl comprising a cam surface; a push device comprising a cam follower capable of moving on the cam surface in order to move the movable pawl from the released position to the locking position; an actuating lever mounted pivotally about an actuating axis configured to move the push device, the actuating lever comprising an outer circumference having a first angular positioning notch and a second angular positioning notch;and a positioning member cooperating with the outer periphery of the actuating lever, the positioning member having a bearing surface configured to engage in the first angular positioning notch when the movable pawl is in the locked position and in the second angular positioning notch when the movable pawl is in the released position;

[0012] the positioning device comprising a flexible blade exerting a force, directly or indirectly, on the external periphery of the actuating lever, the flexible blade comprising a shape folded upon itself to constitute in profile view a V shape.

[0013] By V shape, we mean that the flexible blade has, in profile view, substantially the shape of the capital letter V, the shape of the capital letter V comprising two branches inclined to each other at an angle between 0° and 80°, the intersection of the two branches being pointed or radiating.

[0014] For the purposes of this application: "Axially" means "parallel to the axis of actuation"; "radially" means "along an axis belonging to a plane orthogonal to the axis of actuation and intersecting this axis of actuation"; "angularly" or "circumferentially" means "around the axis of actuation"; the terms "external" and "internal" are used to define the relative position of a component with respect to the axis of rotation for which it is concentric, a component close to said axis is thus qualified as internal as opposed to an external component located radially on the periphery; two parts are said to be "fixed" or "rigidly joined" when they are permanently immobilized relative to each other, this immobilization being able to result from a fixing of the first part to the second part directly or by means of one or more intermediate parts.

[0015] The flexible blade is a simple and economical solution that allows easy determination of a geometry compatible with a limited available space while ensuring sufficient rigidity and mechanical resistance to keep the locking mechanism in position.

[0016] The V-shape allows for the creation, within a limited available volume, of a flexible blade with a significant flexural length. Compared to flexible blades with a flat or slightly bent flexural section of the prior art, the V-shaped blade can achieve equivalent stiffness and mechanical strength while occupying a smaller footprint, typically a 20 to 60% reduction in circumferential dimensions.

[0017] According to a further feature of the invention, the V-shape comprises a first flat wall and a second flat wall, a folding angle being established between the first flat wall and the second flat wall, the folding angle being between 0° and 80°, the folding angle being preferably between 0° and 40°.

[0018] The bending angle, according to this last characteristic, minimizes the radial bulk of the flexible blade. The chosen angle value also allows adjustment of the force exerted by the flexible blade on the outer circumference of the actuating lever.

[0019] According to a further feature of the invention, a curved wall connects the first flat wall and the second flat wall.

[0020] According to an additional feature of the invention, the curved wall has a radius of curvature between 2 mm and 10 mm.

[0021] According to a further feature of the invention, a radius of curvature of the curved wall, a thickness of the flexible blade and a ratio equal to the ratio between the radius of curvature and the thickness of the flexible blade are established, the ratio being between 2 and 8.

[0022] The curved wall as defined according to these last three characteristics makes it possible to adapt the stiffness of the flexible blade while limiting the concentrations of mechanical stresses within it.

[0023] According to a further feature of the invention, the first flat wall and the second flat wall are parallel to the actuation axis.

[0024] According to a further feature of the invention, the positioning member comprises a rolling element arranged on the flexible blade, the rolling element being configured to roll on the outer perimeter of the actuating lever.

[0025] The rolling element improves the durability of the locking mechanism by limiting wear and relative friction between the outer edge of the actuating lever and the flexible blade.

[0026] Advantageously, the rolling element can be a cylindrical roller. A complementary shape can then be provided on the end of the flexible blade to create a pivot joint between the cylindrical roller and the flexible blade.

[0027] According to a further feature of the invention, the flexible blade comprises a first bent fixing tab and a second bent fixing tab, the first and second bent fixing tabs being bent at an angle of 90° from a first portion of the flexible blade and positioned axially on either side of said first portion of the flexible blade.

[0028] Thanks to this last feature, the flexible blade has a fixing zone on either side of its flexing part, which has the effect of distributing the load evenly in the flexible blade and thus reducing the mechanical stresses in it.

[0029] According to a further feature of the invention, the first bent fixing tab is bent in the opposite direction to the second bent fixing tab.

[0030] This last feature ensures that the first bent mounting tab is not axially aligned with the second bent mounting tab. Therefore, the first bent mounting tab does not obstruct the passage of a fastening tool to access the second bent mounting tab, and vice versa. Access to the first and second bent mounting tabs for attaching the positioning element is thus simplified.

[0031] According to a further feature of the invention, the first bent fixing lug and the second bent fixing lug are offset from each other axially in a direction parallel to the actuation axis.

[0032] Thanks to this design, the actuating lever and the positioning element are assembled along parallel axes. They can therefore be easily mounted together during the same assembly operation. The axial offset of the first bent mounting tab relative to the second bent mounting tab simplifies the assembly of the positioning element by performing it sequentially. First, pre-positioning is carried out using the first bent mounting tab, which may, for example, have a hole for inserting onto a centering pin fixed to the transmission housing. Then, complete immobilization is achieved using the second bent mounting tab, for example, by means of a screw connecting the second bent mounting tab to the transmission housing.

[0033] According to a further feature of the invention, the locking mechanism comprises: a first fixing means, in particular a centering pin, cooperating with the first bent fixing lug to block the movement of the positioning member in a plane perpendicular to the actuation axis; and a second fixing means, in particular a screw, cooperating with the second bent fixing lug to block the movement of the positioning member along an axis parallel to the actuation axis.

[0034] The fixing of the positioning element according to this last characteristic can be carried out in relation to any type of component on which the locking mechanism can be mounted, in particular the transmission casing.

[0035] Thus, the positioning element is fixed in an isostatic manner. In other words, all degrees of freedom of movement of the positioning element are blocked, while ensuring easy assembly without risk of component deformation.

[0036] According to a further feature of the invention, the folded fixing tab has a first cutout, preferably circular, configured to be centered and fitted on a centering pin, a first diametrical clearance being defined between the circular cutout and the centering pin, preferably the first diametrical clearance being between 0.05 and 0.2 mm.

[0037] According to a further feature of the invention, the second bent fixing tab has a second cutout, preferably circular, configured to cooperate with the body of a screw, a second diametrical clearance being defined between the second cutout and the body of the screw, the second diametrical clearance being greater than the first diametrical clearance, preferably the second diametrical clearance being greater than 0.5 mm.

[0038] Thanks to this last feature, the risk of assembly failure due to component manufacturing tolerances is eliminated.

[0039] According to an additional feature of the invention, the positioning device is fixed on the transmission housing.

[0040] According to an additional feature of the invention, the actuating lever is pivotally mounted on the transmission housing.

[0041] According to an additional feature of the invention, the movable pawl is pivotally mounted on the transmission housing.

[0042] According to an additional feature of the invention, the transmission housing comprises bearing surfaces positioned by complementary shape opposite the first and second folded fixing lugs of the positioning member.

[0043] According to an additional feature of the invention, the flexible blade has a shape configured to allow free passage along an axis parallel to the actuation axis allowing the assembly of the first and second fastening means.

[0044] This last feature allows the overall shape of the flexible blade to be defined so that no part of it obstructs the passage of a fastening tool. Access to the first and second folded mounting tabs for attaching the positioning element is thus simplified.

[0045] According to an additional feature of the invention, the actuating axis of the actuating lever is parallel to the pivoting axis of the movable ratchet.

[0046] Thanks to this feature, assembly can be further simplified because all the components of the locking mechanism that mount on the transmission housing can be mounted along parallel axes, so they can all be mounted during the same assembly operation.

[0047] According to a further feature of the invention, the outer perimeter of the actuating lever consists of surfaces parallel to the actuating axis.

[0048] According to a further feature of the invention, the actuating lever is formed from a plate cut from a sheet of constant thickness, the outer perimeter of the actuating lever being obtained from a slice of the plate.

[0049] Thus, the actuation lever can be produced using a simple and economical manufacturing process.

[0050] According to an additional feature of the invention, the flexible blade deforms elastically and / or radially as it travels around the outer perimeter of the actuating lever.

[0051] According to a further feature of the invention, the flexible blade is formed in one piece from a strip of metallic material, in particular from a sheet of steel.

[0052] Thus the manufacturing process is simple and economical: from a sheet of constant thickness, typically between 0.5 and 2 mm, a cutting operation, for example press cutting, is carried out to cut the outer and inner contours of the flexible blade, followed by a bending operation to give it the V shape.

[0053] According to a further feature of the invention, the flexible blade is made of a metal which has undergone a hardening treatment, in particular carbonitriding, nitriding, carburizing or quenching.

[0054] This feature increases the mechanical strength of the flexible blade needed to withstand the mechanical stresses transmitted to the locking mechanism.

[0055] According to an additional feature of the invention, the flexible blade has a stiffness between 10 and 50 N / mm.

[0056] According to an additional feature of the invention, the flexible blade makes a radial displacement when the positioning member cooperates with the outer perimeter of the actuating lever, the radial displacement varying between 1 and 10 mm regardless of the angular position of the actuating lever.

[0057] According to a further feature of the invention, the actuating lever is driven in rotation, directly or indirectly, by a rotor shaft of an electric motor.

[0058] Furthermore, the invention relates to a transmission system comprising a shaft equipped with at least one locking recess and a locking mechanism as described above. Brief description of the figures

[0059] There figure 1 is a front view of a locking mechanism according to one embodiment of the invention. figure 2 is a perspective view of the figure 1 . There figure 3 is a perspective view of a portion of the locking mechanism according to one embodiment of the invention. figure 4 is a top view of the figure 3 . There figure 5 is a perspective view of a positioning device according to an embodiment of the invention. figure 6 is a front view of the figure 5 . There figure 7is a perspective view of an actuation lever according to one embodiment of the invention. Description of the implementation methods

[0060] In all figures, identical elements or elements performing the same function are given the same reference numbers. The following embodiments are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference relates to the same embodiment or that the features apply only to a single embodiment. Simple features from different embodiments can also be combined or interchanged to provide other embodiments.

[0061] A locking mechanism for a vehicle's shaft includes, in particular: a movable pawl, a thrusting device, an actuating lever, and a positioning element. The locking mechanism is primarily intended to immobilize a vehicle, such as a car, in a parked position. The various components of the locking mechanism will be described below.

[0062] THE figures 1 and 2 illustrate a locking mechanism according to an embodiment of the invention. In these figures, the locking mechanism comprises a movable pawl 34 located in a transmission housing 1 (partially shown). The movable pawl 34 may be elongated and may have a first end 71 and a second end 72 located at a distance from the first end 71.

[0063] The first end 71 allows, for example, the fixing of the movable ratchet 34 on the transmission housing 1 while allowing the rotational movement of said movable ratchet 34. That is to say, the movable ratchet is mounted pivotally in a plane P around a pivot axis Y1.

[0064] The second end 72 may include a cam surface 36 located on a first lateral face of the movable pawl 34. The second end 72 may further include a locking finger 35 projecting from a second lateral face of the movable pawl 34. The locking finger 35 is intended, when the locking mechanism is engaged, to fit into a locking recess 45. The locking recess 45 is, for example, located on a ratchet wheel 44 which is adapted to receive said locking finger 35, and which is fixed rotationally to the transmission shaft 60 (partially shown) intended to be locked against rotation.

[0065] Thus, the locking mechanism varies between a locked position in which the locking finger 35 is engaged in the locking recess 45 and a released position in which the locking finger 35 is disengaged from said locking recess 45. In the figures 1 and 2 The mechanism for locking the rotation of a shaft is shown in a released position.

[0066] The movable pawl 34 may further include a torsion spring 50. The torsion spring 50 is, for example, wound at the first end 71 of the movable pawl 34. The torsion spring 50 may include a first end 51 which bears against a bearing surface of the transmission housing 1 and a second end 52 which bears against a bearing surface of the movable pawl 34. The torsion spring 50 is arranged to exert a restoring force on the movable pawl 34 in order to return it to the released position.

[0067] The locking mechanism further includes a thrust device 38. The thrust device 38 can be guided along a longitudinal direction X by a guide rail 27 housed in the transmission casing 1. In cases where the thrust device 38 is pushed back by the movable pawl 34 during dynamic phases, the thrust device 38 may come to rest against a lateral wall of the guide rail 27, which thus forms a non-return stop for the thrust device 38. In this case, the thrust device 38 is pushed against the movable pawl 34 by a restoring force exerted by a tension spring 40. This effect can occur, for example, during attempts to engage the device at excessive speed. Above a threshold speed, for example between 3 km / h and 5 km / h, the movable pawl 34 rebounds to prevent engagement, and the thrust device 38 is then pushed back against its stop.The spring 40 surrounds a rod 39 of the thrust device which extends through a first notch 25 of the transmission housing 1 and a second notch 32 of the guide rail 27.

[0068] The thrust device 38 may be in the form of a movable carriage which includes, for example, a first movable roller 41 adapted to move along a longitudinal wall 30 of the guide rail 27. The thrust device 38 may further include a cam follower 42 having a second movable roller which is in contact with the cam surface 36 of the movable pawl 34 and adapted to move along this cam surface 36.

[0069] The thrust device 38 may further include a lug 43 located at the second end of the movable pawl 34. The lug 43 is intended to retain the movable pawl 34 in the plane P.

[0070] To move the movable pawl 34 into the locked position, the rod 39 can be moved through the second notch 32 of the guide rail 27, thereby moving the thrust device 38 along the longitudinal direction X. The movement of the thrust device 38 can cause the first movable roller 41 to move along the guide rail 27 and the cam follower 42 to move along the cam surface 36 of the movable pawl 34. The cam surface 36 may have a slope, and the thrust device 38 can therefore exert pressure, through its movement, towards the cam surface 36 of the movable pawl 34. This pressure can cause the second end of the movable pawl 34 to rotate towards a locking recess, such that the locking finger 35 can engage in a locking recess present, for example, on a ratchet wheel 44.

[0071] THE figures 3 to 7illustrate more particularly an actuation lever 3 and a positioning member 2 of the locking mechanism according to an embodiment of the invention.

[0072] The actuating lever 3 is pivotally mounted around an actuating axis Y2 on the transmission housing 1. A housing 101 (visible on the figure 2The mechanism fitted into the transmission housing 1 can cooperate with a retaining ring 102 to axially lock the actuating lever 3. The actuating lever 3 can be driven in rotation by a drive shaft 303, the drive shaft 303 rotating with a rotor shaft of an electric motor, in particular via gears enabling speed reduction. The actuating lever 3 can be linked to the rod 39, for example via a pivot joint, such that a rotation of the actuating lever 3 around the actuating axis Y2 results in a translation along the longitudinal direction X of the thrusting device 38.

[0073] As illustrated in figure 7The actuating lever 3 further includes an outer rim 300 having a first angular positioning notch 301 and a second angular positioning notch 302. The actuating lever 3 can be formed from a plate cut from a sheet of constant thickness, for example a thickness between 3 and 6 mm, the outer rim 300 being obtained from a slice of the plate.

[0074] As illustrated by the figures 3 And 5The positioning member 2 cooperates with the outer circumference of the actuating lever 3. The positioning member 2 has a bearing surface 204 configured to engage in the first angular positioning notch 301 when the movable pawl 34 is in the locked position and in the second angular positioning notch 302 when the movable pawl 34 is in the released position. The positioning member 2 thus makes it possible to maintain the position of the locking mechanism in a stable and precise manner in the released and / or locked position.

[0075] In this embodiment, the positioning member 2 includes a flexible blade 200 exerting a force, directly or indirectly, on the outer circumference 300 of the actuating lever 3. A rolling element 203, for example a cylindrical roller, arranged on the flexible blade 200 can be configured to roll on the outer circumference 300 of the actuating lever 3.

[0076] The positioning member 2 can be fixed to the transmission housing 1 via a first bent mounting tab 201 and a second bent mounting tab 202 of the flexible blade 200. The first bent mounting tab 201 and the second bent mounting tab 202 can be offset from each other in a direction parallel to the actuation axis Y2. Advantageously, the first bent mounting tab 201 and the second bent mounting tab 202 can be bent at an angle of 90° from a first portion 210 of the flexible blade 200 and positioned axially on either side of said first portion 210 of the flexible blade 200. The first bent mounting tab 201 can be bent in the opposite direction to the second bent mounting tab 202.

[0077] As illustrated on the figures 3 and 4A first fastening means 206, here a centering pin, can cooperate with a circular hole in the first bent mounting tab 201 to limit the displacement of the positioning member 2 relative to the transmission housing 1 in the plane perpendicular P to the actuation axis Y2. Advantageously, a very small diametral clearance, typically between 0.05 mm and 0.2 mm, is provided between the circular hole and the centering pin. A second fastening means 205, here a screw, can cooperate with the second bent mounting tab 202 to prevent the displacement of the positioning member 2 relative to the transmission housing 1 along a fourth axis Y4 parallel to the actuation axis Y2.

[0078] As illustrated on the figure 4Four axes can be defined for assembly on the transmission housing 1: the actuation axis Y2 of the actuating lever 3, the pivot axis Y1 of the movable ratchet 34, the fourth axis Y4 along which the screw 205 can be assembled, and a third axis Y3 along which the centering pin 206 can be assembled. Advantageously, these four axes can be parallel, which allows all these components to be easily mounted during the same assembly operation.

[0079] As illustrated on the figures 5 and 6 The flexible blade 200 comprises a form folded back on itself to form a V-shape. The V-shape may comprise a first flat wall 207 and a second flat wall 208, a folding angle A being established between the first flat wall 207 and the second flat wall 208, the folding angle A preferably being between 0° and 40°, 30° in the example of the figure 6A curved wall 209 can connect the first flat wall 207 and the second flat wall 208, the curved wall 209 having a radius of curvature between 2 mm and 10 mm, 6.5 mm in the example of the figure 6 Advantageously, the radius of curvature of the curved wall 209 can be chosen based on the thickness of the flexible blade 200 in order to improve the compromise between its stiffness and mechanical stress. A ratio equal to the ratio between the radius of curvature and the thickness of the flexible blade 200 can be established, preferably between 2 and 8. In the example of the figure 6 The thickness of the flexible blade 200 is 1.5 mm, so the ratio is 4.3.

[0080] The 200 flexible blade can be formed in one piece from a strip of metallic material. In the example of the figure 6The flexible blade 200 is made from a steel strip which is cut by press to obtain its contours, then bent to obtain its V shape, the first and second fixing tabs bent 201 and 202, and also a complementary shape 211 allowing to constitute a pivot link between the cylindrical roller 203 and the flexible blade 200. The flexible blade 200 can then undergo a hardening treatment to increase its mechanical strength.

[0081] The first flat wall 207 and the second flat wall 208 of the flexible blade 200 can be parallel to the actuation axis Y2. In addition, the shape of the flexible blade 200, in particular its V-shape and / or the choice of the value of the bending angle A, can be chosen so as to leave a passage allowing the assembly of the second fixing means 205 along the fourth axis Y4 and of the first fixing means 206 along the third axis Y3.

[0082] It is emphasized that all features, as they are apparent to a person skilled in the art from the present description, drawings and attached claims, even if in practice they have only been described in relation to other specific features, both individually and in any combinations, can be combined with other features or groups of features disclosed herein, provided that this has not been expressly excluded or that technical circumstances render such combinations impossible or meaningless, the present invention being defined by the following claims.

[0083] The use of the verb "comporter", "comprendre" and its conjugated forms does not exclude the presence of other elements or other steps than those stated in a claim.

[0084] In claims, any reference sign in parentheses shall not be interpreted as a limitation of the claim.

Claims

1. Locking mechanism capable of being mounted in a transmission housing (1) to block rotation of a shaft of a vehicle equipped with at least one locking recess (45), the locking mechanism comprising: - a movable pawl (34) comprising a locking finger (35), the movable pawl (34) being mounted pivoting around a pivot axis (Y1) between a locking position in which the locking finger (35) is engaged in the locking recess (45) and a released position in which the locking finger (35) is disengaged from said locking recess (45), the movable pawl (34) comprising a cam surface (36); - a pushing device (38) having a cam follower (42) capable of moving on the cam surface (36) in order to move the movable pawl (34) from the released position to the locking position; - an actuation lever (3) mounted pivoting around an actuation axis (Y2) and configured to move the pushing device (38), the actuation lever (3) comprising an external perimeter (300) having a first angular positioning notch (301) and a second angular positioning notch (302); and - a positioning member (2) cooperating with the external perimeter (300) of the actuation lever (3), the positioning member (2) having a support surface (204) configured to engage in the first angular positioning notch (301) when the movable pawl (34) is in the locking position and in the second angular positioning notch (302) when the movable pawl (34) is in the released position; characterized in that the positioning member includes a flexible blade (200) exerting a force, directly or indirectly, on the external perimeter (300) of the actuation lever (3), the flexible blade (200) comprising a form folded upon itself to constitute, in profile view, a V-shape.

2. Locking mechanism according to claim 1, wherein the V-shape comprises a first flat wall (207) and a second flat wall (208), a folding angle (A) being established between the first flat wall (207) and the second flat wall (208), the folding angle (A) being between 0° and 80°, the folding angle (A) being preferably between 0° and 40°.

3. Locking mechanism according to claim 2, wherein a curved wall (209) connects the first flat wall (207) and the second flat wall (208).

4. Locking mechanism according to claim 3, wherein the curved wall (209) has a radius of curvature between 2 mm and 10 mm.

5. Locking mechanism according to claim 3 or 4, wherein a radius of curvature of the curved wall, a thickness of the flexible blade, and a ratio equal to the ratio between the radius of curvature and the thickness of the flexible blade are established, the ratio being between 2 and 8.

6. Locking mechanism according to any one of claims 2 to 5, wherein the first flat wall (207) and the second flat wall (208) are parallel to the actuation axis (Y2).

7. Locking mechanism according to any one of the preceding claims, wherein the positioning member (2) includes a rolling element (203) arranged on the flexible blade (200), the rolling element (203) being configured to roll on the external perimeter (300) of the actuation lever (3).

8. Locking mechanism according to any one of the preceding claims, wherein the flexible blade comprises a first folded mounting tab (201) and a second folded mounting tab (202), the first and second folded mounting tabs (201, 202) being folded at an angle of 90° from a first portion (210) of the flexible blade (200) and positioned axially on either side of said first portion (210) of the flexible blade (200).

9. Locking mechanism according to claim 8, wherein the first folded mounting tab (201) is folded in a direction opposite to the second folded mounting tab (202).

10. Locking mechanism according to claim 8 or 9, wherein the first folded mounting tab (201) and the second folded mounting tab (202) are offset from each other axially in a direction parallel to the actuation axis (Y2).

11. Locking mechanism according to any one of claims 8 to 10, wherein: - a first fastening means (206), particularly a centering pin, cooperates with the first folded mounting tab (201) to limit the movement of the positioning member (2) in a plane perpendicular (P) to the actuation axis (Y2); and - a second fastening means (205), particularly a screw, cooperates with the second folded mounting tab (202) to block the movement of the positioning member (2) along an axis parallel to the actuation axis (Y2).

12. Locking mechanism according to claim 11, wherein the flexible blade (200) has a shape configured to leave free a passage along an axis parallel to the actuation axis (Y2) allowing the assembly of the first and second fastening means (205, 206).

13. Locking mechanism according to any one of the preceding claims, wherein the external perimeter (300) of the actuation lever (3) is constituted of surfaces parallel to the actuation axis (Y2).

14. Locking mechanism according to any one of the preceding claims, wherein the flexible blade (200) is formed as a single piece from a strip of metallic material, particularly from a steel sheet.

15. Transmission system comprising a shaft equipped with at least one locking recess (45) and a locking mechanism according to any one of claims 1 to 14.