Locking mechanism, control method of locking mechanism, motor gear unit, and vehicle

Abstract

Disclosed in the present invention is a locking mechanism, comprising an electromagnet and a multi-stage gear transmission mechanism. A locking head of the electromagnet is configured to be embedded during a locking state into a locking recess formed in any gear of the multi-stage gear transmission mechanism, a locking face and a non-locking face are provided in the locking recess, and the distance between the locking face and the non-locking face is greater than the width of the locking head. According to the present invention, the locking mechanism provided with the locking recess structure which is long and wide can ensure the effectiveness of a locking action of a bistable electromagnet, and when the locking head enters the locking recess, there is open space in the front, back, left, and right directions, not obstructing the movement of the locking head, thereby ensuring the effective axial movement of the locking mechanism, canceling a position detection sensor, simplifying module parts, thus reducing the manufacturing cost. Also disclosed in the present invention are a motor gear unit, a control method of the locking mechanism, and a vehicle.

Description

Locking mechanism, locking mechanism control method, motor gear unit and vehicle Technical Field

[0001] The present invention belongs to the technical field of brake systems, and in particular, relates to a locking mechanism, a control method for the locking mechanism, a motor gear unit, and a vehicle. Background Art

[0002] With the electrification transformation of vehicles, wire-controlled brake systems have gradually become a major development trend in the automotive industry. As one of them, the electromechanical brake (EMB) system adopts the form of direct drive of the wheel-end motor. Through the motion conversion mechanism, the torque and rotational motion of the motor are converted into the thrust and translational motion of the connector, pushing the brake pads to clamp the brake disc, thereby obtaining braking force. At the same time, as an emerging braking system, electronic mechanical braking has abandoned large components such as vacuum boosters and hydraulic pipelines, making the vehicle chassis layout simpler and more flexible, and has the advantages of fast and precise pressure regulation, which can significantly improve the braking performance of the vehicle.

[0003] In the existing EMB brake caliper body technical solutions, the brake caliper body structure has a locking mechanism. One of the locking mechanisms uses an electromagnet as a locking power device. The power transmission is pinned and unlocked by extending and retracting the electromagnet locking head, thereby achieving the locking of the entire parking system. However, the bistable electromagnet itself has the characteristic of fast action, and during the entire locking action process, it can only be maintained in the initial two positions, so the action state of the bistable electromagnet can be stuck in any position.

[0004] Patent document with publication number CN218598679U discloses a parking brake locking device, in which many bosses extend from the end face of the gear to cooperate with the head of the electromagnet push rod to realize the locking function. Due to the existence of the parking clamping force, there is a risk of boss strength. At the same time, since the electromagnet acts instantaneously, there may be a risk of invalid locking if the system is directly pinned by the electromagnet. Therefore, an external position detection system is required to realize the position state of the locking head. However, since the structural layout of the parking brake locking device is very compact, there is no relevant layout space around it to arrange the position detection system. At the same time, the position detection system requires a connector for signal transmission, and there is no space for the arrangement of the connector, which makes it difficult to arrange the position detection system. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a locking mechanism, the purpose of which is to ensure the effectiveness of the locking action of the bistable electromagnet, simplify the parts of the mechanism, and reduce manufacturing costs.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is as follows: a locking mechanism includes an electromagnet and a multi-stage gear transmission mechanism, the locking head of the electromagnet is configured to be embedded in a locking groove provided on any one gear of the multi-stage gear transmission mechanism when in a locked state, a locking surface and a non-locking surface are provided in the locking groove, and the distance between the locking surface and the non-locking surface is greater than the width of the locking head.

[0007] The locking head is provided with a first contact surface for contacting the non-locking surface and a second contact surface for contacting the locking surface, and in the locked state, the second contact surface keeps in contact with the locking surface.

[0008] The first contact surface on the locking head and the non-locking surface of the locking groove are in relatively matched plane contact and / or relatively matched inclined surface contact. The first contact surface on the locking head and the non-contact surface of the locking groove can be an inclined surface, a flat surface, or a combination of a flat surface and an inclined surface.

[0009] A plurality of locking grooves are provided on the end surface of the gear, and all the locking grooves are evenly distributed along the circumferential direction on the end surface of the gear.

[0010] A plurality of locking grooves are arranged on the outer circumferential surface of the gear, and all the locking grooves are evenly distributed along the circumferential direction on the outer circumferential surface of the gear.

[0011] The gear is a driven gear of the first stage transmission mechanism in the multi-stage gear transmission mechanism.

[0012] The multi-stage gear transmission mechanism includes a first-stage transmission mechanism and a second-stage transmission mechanism. The driving gear of the first-stage transmission mechanism is connected to the motor, and the driven gear of the first-stage transmission mechanism is connected to the driving gear of the second-stage transmission mechanism to form a double gear. The driven gear of the second-stage transmission mechanism is the output gear.

[0013] A deweighting groove is provided on the gear, and a plurality of deweighting grooves are provided.

[0014] All the deweighting grooves provided on the gear are evenly distributed along the circumferential direction.

[0015] The electromagnet is a bistable electromagnet, which is press-fitted into a cavity provided on the MGU housing through an interference fit of an end cover and matched with the locking groove position.

[0016] The present invention also provides a control method for a locking mechanism. When the vehicle is parked, the clamping force of the vehicle brake is first set to a first clamping force, the first clamping force is an over-target clamping force, the electromagnet is energized, the locking head extends, and then the gear is controlled to rotate until the locking head contacts the locking surface to complete the locking.

[0017] When the vehicle is parked, the electromagnet is energized, and the first contact surface on the locking head contacts the end point of the non-locking surface in the target locking groove. Then, the electromagnet remains energized to control the gear to rotate in the first direction, and the gear retracts until the locking head completely enters the target locking groove, and the second contact surface of the locking head contacts the locking surface in the target locking groove, completing the locking action; during this process, the electromagnet remains energized, so that the locking head is always in an extended state, ensuring that the locking head can automatically embed into the locking groove.

[0018] When the vehicle is parked, the electromagnet is energized, and the first contact surface on the locking head contacts the non-locking surface in the target locking groove. Then, the electromagnet remains energized to control the gear to rotate in the first direction, and the gear retracts until the locking head completely enters the target locking groove, and the second contact surface of the locking head contacts the locking surface in the target locking groove, completing the locking action.

[0019] When the vehicle is parked, the electromagnet is energized, and the locking head is pushed to the middle position in the length direction of the target locking groove. The electromagnet remains energized to control the gear to rotate in the first direction, and the gear retracts until the locking head completely enters the target locking groove, and the second contact surface of the locking head contacts the locking surface in the target locking groove, completing the locking action.

[0020] When the vehicle is parked, the electromagnet is energized, and the top end of the locking head is stuck to the edge of the locking surface of the target locking groove. Then, the electromagnet remains energized, and the motor needs to control the gear to rotate in the first direction to make the gear retract. However, at this time, the gear cannot retract and the motor cannot operate. Then, the gear is controlled to rotate in the second direction for a certain angle, and then the gear is controlled to rotate in the first direction again to make the gear retract until the locking head completely enters the target locking groove, completing the locking action.

[0021] When the vehicle is parked, the electromagnet is energized, and the locking head hits a portion of the gear where no locking groove is provided. Then, the electromagnet remains energized, controlling the gear to rotate, and the gear retracts until the locking head completely enters the target locking groove, completing the locking action.

[0022] The present invention also provides a control method for a locking mechanism. When the vehicle is parked, the clamping force of the vehicle brake is first set to a second clamping force, which is a smaller clamping force. The electromagnet is energized, the locking head extends, and then the motor is controlled to drive the gear to rotate. The locking position is determined by identifying the current size of the motor. After the vehicle brake reaches the required target clamping force, the motor ends its action and the locking is completed.

[0023] When the vehicle is parked, the electromagnet is energized, and the first contact surface on the locking head contacts the end point of the non-locking end surface in the first locking groove. Then, the electromagnet remains energized, and the motor controls the gear to rotate in the second direction, so that the gear rotates until the second locking groove is aligned with the locking head. Then, the motor controls the gear to rotate in the first direction again, so that the gear retracts until the locking head completely enters the second locking groove, completing the locking action.

[0024] When the vehicle is parked, the electromagnet is energized, and the first contact surface on the locking head contacts the non-locking end surface in the first locking groove. Then, the electromagnet remains energized, and the motor controls the gear to rotate in the second direction. During the rotation of the gear, the non-locking end surface in the first locking groove pushes the locking head out of the first locking groove. When the gear rotates to a state where the second locking groove is aligned with the locking head, the motor controls the gear to rotate in the first direction again, causing the gear to retract until the locking head completely enters the second locking groove, completing the locking action.

[0025] When the vehicle is parked, the electromagnet is energized and the locking head is pushed to the middle position in the length direction of the first locking groove. Then, the electromagnet remains energized and the motor controls the gear to rotate in the second direction. During the rotation of the gear, when the non-locking end surface in the first locking groove contacts the locking head, the locking head is pushed out of the first locking groove. When the gear rotates to a state where the second locking groove is aligned with the locking head, the motor controls the gear to rotate in the first direction again, causing the gear to retract until the locking head completely enters the second locking groove, thereby completing the locking action.

[0026] When the vehicle is parked, the electromagnet is energized, and the top end of the locking head is stuck to the edge of the locking end face of the first locking groove. Then, the electromagnet remains energized, and the motor controls the gear to rotate in the second direction. During the rotation of the gear, when the non-locking end face in the first locking groove contacts the locking head, it pushes the locking head out of the first locking groove. When the gear rotates to a state where the second locking groove is aligned with the locking head, the motor controls the gear to rotate in the first direction again, causing the gear to retract until the locking head completely enters the second locking groove, completing the locking action.

[0027] When the vehicle is parked, the electromagnet is energized, and the locking head presses against a portion of the gear where no locking groove is provided. Then, the electromagnet remains energized, and the motor controls the gear to rotate in the second direction, so that the gear rotates until the locking groove closest to the locking head is aligned with the locking head. Then, the motor controls the gear to rotate in the first direction, so that the gear retracts, until the locking head completely enters the locking groove, completing the locking action.

[0028] The present invention also provides a motor gear unit comprising the locking mechanism.

[0029] The present invention also provides a vehicle comprising the motor gear unit.

[0030] The locking mechanism of the present invention can ensure the effectiveness of the locking action of the bistable electromagnet. When the locking head enters the locking groove, the specifically wide open space in the front, back, left and right sides will not hinder the movement of the locking head, thereby ensuring the effectiveness of the axial movement of the locking mechanism. In this way, the detection sensor can be eliminated, the module components are simplified, and the manufacturing cost is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] This manual includes the following drawings, which show the following contents:

[0032] FIG1 is a schematic structural diagram of a duplex gear according to the first embodiment;

[0033] FIG2 is a schematic structural diagram of a duplex gear according to a second embodiment;

[0034] FIG3 is a schematic cross-sectional view of a motor gear unit;

[0035] Figure 4 is a schematic diagram of the assembly of the double gear and the locking mechanism;

[0036] FIG5 is a schematic diagram of the locking head and the locking groove in the unlocked state;

[0037] Figure 6 is a schematic diagram of the locking head and the locking groove in the locked state;

[0038] FIG7 is a schematic diagram showing the contact state between the first contact surface endpoint on the locking head and the non-locking surface endpoint in the target locking groove during simulated parking;

[0039] FIG8 is a schematic diagram showing the contact state between the first contact surface on the locking head and the non-locking surface in the target locking groove during simulated parking;

[0040] FIG9 is a schematic diagram showing a state in which the locking head is positioned in the middle of the locking groove during simulated parking;

[0041] FIG10 is a schematic diagram showing a state in which the top of the locking head is stuck to the locking surface edge of the locking groove during parking simulation;

[0042] FIG11 is a schematic diagram showing the position of the locking head against the non-locking groove of the gear during simulated parking;

[0043] Items marked in the figure are: 1. Duplex gear; 1a. Locking groove 1a; 1a1. Locking surface; 1a2. Non-locking surface; 1b. Deweighting groove; 2. ECU shell cover; 3. Circuit board; 4. ECU housing; 5. Output gear; 6. Electromagnet; 6a. Locking head; 7. Motor gear; 8. MGU housing; 8a. Cavity; 9. Motor; 10. Axle pin. DETAILED DESCRIPTION

[0044] The following is a further detailed description of the specific implementation methods of the present invention through the description of embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present invention and to facilitate its implementation.

[0045] As shown in Figures 1 to 11, the present invention provides a locking mechanism suitable for vehicle brakes, including an electromagnet 6 and a multi-stage gear transmission mechanism. The locking head 6a of the electromagnet 6 is configured to be embedded in a locking groove 1a provided on any one gear of the multi-stage gear transmission mechanism in a locked state. A locking surface 1a1 and a non-locking surface 1a2 are provided in the locking groove 1a, and the distance between the locking surface 1a1 and the non-locking surface 1a2 is greater than the width of the locking head 6a.

[0046] Specifically, as shown in Figures 1 and 2, a locking groove 1a with a certain length is arranged on any one-stage gear, and the electromagnet 6 is arranged in the cavity 8a set on the MGU housing 8 as a driving device. The locking head 6a of the electromagnet 6 extends and retracts to cooperate with and unlock the locking groove 1a on the gear, thereby realizing the parking lock function of the entire brake.

[0047] As shown in Figures 1 and 2, a locking surface 1a1 and a non-locking surface 1a2 are provided in the locking groove 1a. The locking surface 1a1 and the non-locking surface 1a2 are inner wall surfaces at opposite ends in the length direction of the locking groove 1a. The locking surface 1a1 is used to contact the surface of the locking head 6a in the locked state, and the non-locking surface 1a2 is used to push the locking head 6a out of the locking groove 1a during the rotation of the gear. The non-locking surface 1a2 is a plane inclined in the locking groove 1a, and an angle is formed between the non-locking surface 1a2 and the axis of the gear, and the angle is acute. The moving direction of the locking head 6a is parallel to the axis of the gear. A first contact surface in contact with the non-locking surface 1a2 is provided on the locking head 6a, and the first contact surface is an inclined plane, and an angle is formed between the first contact surface and the moving direction of the locking head 6a, and the angle is acute. The inclination angle of the first contact surface and the non-locking surface 1a2 is the same. The locking surface 1a1 is a plane parallel to the axis of the gear. A second contact surface in contact with the locking surface 1a1 is provided on the locking head 6a. The second contact surface is a plane parallel to the moving direction of the locking head 6a. In the locked state, the second contact surface is in contact with the locking surface 1a1, and the locking head 6a plays a circumferential limiting role on the gear to achieve locking.

[0048] Preferably, a plurality of locking grooves 1a are provided, and all locking grooves 1a are evenly distributed along the circumference of the gear with the axis of the gear as the center line. In the locked state, the locking head 6a is inserted into one of the locking grooves 1a. The width of the locking groove 1a is greater than the width of the locking head 6a. The width direction of the locking head 6a is parallel to the width direction of the locking groove 1a, and the length direction of the locking groove 1a is perpendicular to its width direction. The length and width of the locking groove 1a are both greater than the length and width of the locking head 6a, ensuring that the locking head 6a has enough time to fully enter the locking groove 1a. In this way, when the lock head enters the locking groove 1a, the specific open space in front, behind, left and right will not hinder the movement of the locking head 6a, thereby ensuring the effectiveness of the axial movement of the locking mechanism, thereby eliminating the detection sensor, simplifying the module components, and reducing manufacturing costs.

[0049] As shown in FIG1 and FIG2 , a deweighting groove 1b is provided on the gear. A plurality of deweighting grooves 1b are provided. All the deweighting grooves 1b provided on the gear are evenly distributed along the circumferential direction with the axis of the gear as the center line, thereby achieving a weight reduction effect.

[0050] Preferably, the electromagnet 6 is a bistable electromagnet, which is press-fitted into a cavity provided on the MGU housing 8 through an interference fit of an end cover, and is matched with the locking groove 1 a.

[0051] As shown in Figures 3 to 6, the multi-stage gear transmission mechanism includes a first-stage transmission mechanism and a second-stage transmission mechanism. The driving gear of the first-stage transmission mechanism is connected to a motor, which provides driving force. The driven gear of the first-stage transmission mechanism is provided with a locking groove 1a, and the driving gear and the driven gear of the first-stage transmission mechanism mesh with each other. The driven gear of the first-stage transmission mechanism is fixedly connected to the driving gear of the second-stage transmission mechanism, forming a double gear 1. The driven gear of the second-stage transmission mechanism serves as the output gear 5, which meshes with the driving gear of the second-stage transmission mechanism, and the output gear 5 outputs power.

[0052] When the vehicle is parked, the clamping force exceeding the target is first set, the electromagnet 6 is energized, the locking head 6a of the electromagnet 6 extends, and then the motor is used to control the rotation of the double gear 1. The double gear 1 retracts until the locking head 6a contacts the locking groove 1a, and the locking head 6a is inserted into the locking groove 1a to complete the locking.

[0053] As a modified implementation scheme, when the vehicle is parked, a smaller clamping force can be set first, the electromagnet 6 is energized, the locking head 6a is extended, and then the motor is controlled to clamp slowly. The locking position is determined by identifying the current, and the action is terminated when the clamping force position is met to complete the locking.

[0054] Example 1

[0055] As shown in Figure 1, the passive gear of the first-stage transmission mechanism is fixedly connected to the active gear of the second-stage transmission mechanism to form a double gear 1. A plurality of locking grooves 1a are provided on the end face of the double gear 1. All locking grooves 1a are evenly distributed along the circumferential direction on the end face of the gear. The end face of the double gear 1 is the plane of the double gear 1 facing the electromagnet 6, and the end face of the double gear 1 is perpendicular to the axis of the double gear 1.

[0056] In this embodiment, eight locking grooves 1a are provided. These are arc-shaped grooves, with their axes aligned with the axis of the gear. Eight de-weighting grooves 1b are also provided. These de-weighting grooves 1b and the locking grooves 1a are arranged parallel to each other from the center of the circle to the periphery. These de-weighting grooves 1b and the locking grooves 1a are staggered circumferentially. This design enhances gear strength.

[0057] Example 2

[0058] As shown in Figure 2, the passive gear of the first-stage transmission mechanism is fixedly connected to the driving gear of the second-stage transmission mechanism to form a duplex gear 1. A plurality of locking grooves 1a are provided on the outer circumferential surface of the duplex gear 1. All locking grooves 1a are evenly distributed along the circumferential direction on the outer circumferential surface of the gear. The outer circumferential surface of the duplex gear 1 is the cylindrical surface on the duplex gear 1, and the axis of the outer circumferential surface of the duplex gear 1 is also the axis of the duplex gear 1.

[0059] In Example 1, the locking groove is arranged on the horizontal end face of the gear, so the electromagnet must be arranged axially, and the locking mechanism forms an axial assembly form. In this embodiment, the locking groove is arranged on the vertical surface of the gear periphery, so the electromagnet can be arranged horizontally, and the locking mechanism forms a horizontal assembly form. Compared with the arrangement in Example 1, this can shorten the axial dimension of the entire caliper, and the EMB caliper is more compatible with a wider range of vehicle models.

[0060] In this embodiment, eight locking grooves 1a are provided. These are arc-shaped grooves, with their axes aligned with the axis of the gear. Eight de-weighting grooves 1b are also provided. These de-weighting grooves 1b and the locking grooves 1a are arranged parallel to each other from the center of the circle to the periphery. These de-weighting grooves 1b and the locking grooves 1a are staggered circumferentially. This design enhances gear strength.

[0061] Example 3

[0062] This embodiment provides a motor-gear unit including the locking mechanism described above. As shown in Figures 3 and 4, the motor-gear unit further includes an MGU housing 8, an ECU housing cover 2, an ECU housing 4, a circuit board 3, and a motor. The ECU housing 4 is fixedly mounted on the MGU housing 8, the ECU housing cover 2 is fixedly mounted on the ECU housing 4, and an electromagnet 6 is disposed within the MGU housing 8. The motor gear 7 is axially arranged with the motor, which is disposed within a cavity provided in the MGU housing 8. The duplex gear 1 is disposed on an axle pin 10, which is press-fitted onto the MGU housing 8. The electromagnet 6 is disposed within another cavity 8a provided in the MGU housing 8. The circuit board 3 is disposed within the ECU housing 4, and the electromagnet 6 and circuit board 3 are connected via a connector.

[0063] As shown in Figures 5 and 6, when unlocked, the locking head 6a is in a retracted state, at which time the locking head 6a and the locking groove 1a are in a decoupled state. When locked, the locking head 6a is in an extended state, at which time the locking head 6a extends into the locking groove 1a, and the two are in a combined state to complete the locking.

[0064] Example 4

[0065] Since the state of the duplex gear 1 during parking lock is random, the position of the locking groove on the duplex gear 1 corresponding to the locking head 6a of the electromagnet 6 during locking is random. There are five working conditions, as shown in Figures 7 to 11:

[0066] The first control method for the locking mechanism is: when the vehicle is parked, the clamping force of the vehicle brake is first set to the first clamping force, and the first clamping force is an over-target clamping force (when parking, the parking clamping force is a target clamping force set according to requirements, and the target clamping force is maintained for a long time during parking. Since this control method adjusts the position of the locking groove and the locking head by controlling the retraction of the locking gear by the motor, and the retraction of the locking gear will cause the clamping force of the wheel end to become smaller, the first clamping force generated by the brake needs to be set to be greater than the target clamping force required by the brake at the beginning of parking, so that the clamping force when retracting to the locked state is just within the target clamping force range), the electromagnet 6 is energized, the locking head 6a extends, and then the motor controls the double gear 1 to retract until the locking head 6a contacts the locking groove to complete the locking; the specific execution method is as follows:

[0067] The first operating condition operates as follows: As shown in Figure 7 , when the vehicle is parked, electromagnet 6 is energized, causing the first contact surface on the locking head 6a to contact the endpoint of the non-locking surface 1a2 in the target locking groove. Then, while electromagnet 6 remains energized, the motor controls the duplex gear 1 to rotate at a low speed in the first direction, causing the duplex gear 1 to retract until the locking head 6a fully enters the target locking groove. The second contact surface of the locking head 6a contacts the locking surface 1a1 in the target locking groove, completing the locking operation. During this process, electromagnet 6 remains energized, keeping the locking head 6a in the extended position and ensuring that the locking head 6a automatically engages the locking groove.

[0068] The working process of the second working condition is as follows: as shown in Figure 8, when the vehicle is parked, the electromagnet 6 is energized, and the first contact surface on the locking head 6a contacts the non-locking surface 1a2 in the target locking groove. Then, the electromagnet 6 remains energized, and the motor controls the duplex gear 1 to rotate at a low speed in the first direction, and the duplex gear 1 retracts until the locking head 6a completely enters the target locking groove, and the second contact surface of the locking head 6a contacts the locking surface 1a1 in the target locking groove, completing the locking action.

[0069] The working process of the third working condition is as follows: as shown in FIG9 , when the vehicle is parked, the electromagnet 6 is energized, and the locking head 6a is pushed to the middle position in the length direction of the target locking groove. The electromagnet 6 remains energized, and the motor controls the duplex gear 1 to rotate at a low speed in the first direction, and the duplex gear 1 retracts until the locking head 6a completely enters the target locking groove, and the second contact surface of the locking head 6a contacts the locking surface 1a1 in the target locking groove, completing the locking action.

[0070] The working process of the fourth working condition is as follows: as shown in Figure 10, when the vehicle is parked, the electromagnet 6 is energized, and the top of the locking head 6a is stuck to the edge of the locking surface 1a1 of the target locking groove. Then, the electromagnet 6 remains energized, and the motor needs to control the double gear 1 to rotate at a low speed in the first direction to make the double gear 1 retract. However, at this time, the double gear 1 cannot retract and the motor cannot operate. At this time, this working condition can be judged by the motor unable to rotate signal, and then the motor can be controlled to operate in the opposite direction. The motor controls the double gear 1 to rotate a certain angle in the second direction, and then the motor controls the double gear 1 to rotate at a low speed in the first direction (the first direction and the second direction are opposite rotation directions. If the first direction is clockwise, the second direction is counterclockwise) to make the double gear 1 retract until the locking head 6a completely enters the target locking groove and the locking action is completed. Under this working condition, when the locking head 6a of the electromagnet 6 presses against the edge of the locking surface 1a1 of the target locking groove, although the second contact surface contacts the locking surface 1a1, the insertion depth is not deep enough or it is stuck, so the gear cannot move and the double gear 1 cannot retreat. Therefore, it is necessary to control the motor to run in reverse first.

[0071] The working process of the fifth working condition is as follows: as shown in FIG11 , when the vehicle is parked, the electromagnet 6 is energized, and the locking head 6a presses against a portion of the gear where no locking groove is provided. Then, the electromagnet 6 remains energized, and the motor controls the duplex gear 1 to rotate at a low speed, and the duplex gear 1 retracts until the locking head 6a completely enters the target locking groove, completing the locking action.

[0072] Example 5

[0073] The second control method for the locking mechanism is as follows: when the vehicle is parked, the clamping force of the vehicle brake is first set to a second clamping force, which is a smaller clamping force and is smaller than the target clamping force required by the vehicle brake. The electromagnet 6 is energized, the locking head 6a extends, and then the motor is controlled to rotate slowly. The locking position is determined by identifying the current of the motor. After the vehicle brake reaches the required target clamping force, the motor stops moving and the locking is completed. The specific implementation method is as follows.

[0074] The first operating condition operates as follows: when the vehicle is parked, electromagnet 6 is energized, causing the first contact surface on the locking head 6a to contact the endpoint of the non-locking surface 1a2 in the first locking groove. Electromagnet 6 then remains energized, and the motor controls the duplex gear 1 to rotate at a low speed in the second direction until the second locking groove is aligned with the locking head 6a. The motor then controls the duplex gear 1 to rotate at a low speed in the first direction (the first and second directions are opposite rotation directions; if the first direction is clockwise, the second direction is counterclockwise. When the motor controls the duplex gear 1 to rotate in the second direction, the brake can be re-clamped). This causes the duplex gear 1 to retract until the locking head 6a fully enters the second locking groove, completing the locking action. The first and second locking grooves are circumferentially adjacent locking grooves on the duplex gear 1.

[0075] The second operating condition operates as follows: when the vehicle is parked, electromagnet 6 is energized, causing the first contact surface on the locking head 6a to contact the non-locking surface 1a2 in the first locking groove. Then, while electromagnet 6 remains energized, the motor controls the duplex gear 1 to rotate at a low speed in the second direction. During the rotation of the duplex gear 1, the non-locking surface 1a2 in the first locking groove pushes the locking head 6a out of the first locking groove. When the duplex gear 1 rotates until the second locking groove is aligned with the locking head 6a, the motor controls the duplex gear 1 to rotate at a low speed in the first direction, causing the duplex gear 1 to retract until the locking head 6a fully enters the second locking groove, completing the locking action. The first locking groove and the second locking groove are two circumferentially adjacent locking grooves on the duplex gear 1.

[0076] The third operating condition operates as follows: when the vehicle is parked, electromagnet 6 is energized, and locking head 6a is pushed to the middle position in the longitudinal direction of the first locking groove. Then, electromagnet 6 remains energized, and the motor controls the duplex gear 1 to rotate at a low speed in the second direction. During the rotation of duplex gear 1, when the non-locking surface 1a2 in the first locking groove contacts the locking head 6a, it pushes the locking head 6a out of the first locking groove. When the duplex gear 1 rotates until the second locking groove is aligned with the locking head 6a, the motor controls the duplex gear 1 to rotate at a low speed in the first direction, causing the duplex gear 1 to retract until the locking head 6a fully enters the second locking groove, completing the locking action. The first locking groove and the second locking groove are two circumferentially adjacent locking grooves on the duplex gear 1.

[0077] The fourth operating condition operates as follows: when the vehicle is parked, electromagnet 6 is energized, causing the top end of locking head 6a to engage the edge of locking surface 1a1 of the first locking groove. Electromagnet 6 then remains energized, and the motor controls the duplex gear 1 to rotate at a low speed in the second direction. During the rotation of duplex gear 1, when the non-locking surface 1a2 in the first locking groove contacts the locking head 6a, it pushes the locking head 6a out of the first locking groove. When duplex gear 1 rotates until the second locking groove is aligned with the locking head 6a, the motor controls the duplex gear 1 to rotate at a low speed in the first direction, causing the duplex gear 1 to retract until the locking head 6a fully enters the second locking groove, completing the locking operation. The first locking groove and the second locking groove are two circumferentially adjacent locking grooves on the duplex gear 1.

[0078] The working process of the fifth working condition is as follows: when the vehicle is parked, the electromagnet 6 is energized, and the locking head 6a presses against the portion of the gear where the locking groove is not provided. Then, the electromagnet 6 remains energized, and the motor controls the duplex gear 1 to rotate at a low speed in the second direction, so that the duplex gear 1 rotates until the locking groove closest to the locking head 6a is aligned with the locking head 6a. Then, the motor controls the duplex gear 1 to rotate at a low speed in the first direction, so that the duplex gear 1 retracts until the locking head 6a completely enters the locking groove, completing the locking action.

[0079] The present invention has been described above with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described method. Any non-substantial improvements made using the method concepts and technical solutions of the present invention, or any direct application of the above-described concepts and technical solutions to other situations without modification, fall within the scope of protection of the present invention.

Claims

1. The locking mechanism comprises an electromagnet and a multi-stage gear transmission mechanism, characterized in that: The locking head of the electromagnet is configured to be embedded in a locking groove provided on any gear of the multi-stage gear transmission mechanism in a locked state, a locking surface and a non-locking surface are provided in the locking groove, and a distance between the locking surface and the non-locking surface is greater than a width of the locking head.

2. The locking mechanism according to claim 1, characterized in that: The locking head is provided with a first contact surface for contacting the non-locking surface and a second contact surface for contacting the locking surface, and in the locked state, the second contact surface keeps in contact with the locking surface.

3. The locking mechanism according to claim 1, characterized in that: The first contact surface on the locking head and the non-locking surface of the locking groove are in corresponding plane contact and / or corresponding inclined surface contact.

4. The locking mechanism according to any one of claims 1 to 3, characterized in that: A plurality of locking grooves are arranged on the end surface of the gear, and all the locking grooves are evenly distributed along the circumferential direction on the end surface of the gear.

5. The locking mechanism according to any one of claims 1 to 3, characterized in that: A plurality of locking grooves are arranged on the outer circumferential surface of the gear, and all the locking grooves are evenly distributed along the circumferential direction on the outer circumferential surface of the gear.

6. The locking mechanism according to any one of claims 1 to 3, characterized in that: The gear is a driven gear of a first-stage transmission mechanism in the multi-stage gear transmission mechanism.

7. The locking mechanism according to claim 6, characterized in that: The multi-stage gear transmission mechanism comprises a first-stage transmission mechanism and a second-stage transmission mechanism, wherein the driving gear of the first-stage transmission mechanism is connected to the motor, the driven gear of the first-stage transmission mechanism is connected to the driving gear of the second-stage transmission mechanism to form a double gear, and the driven gear of the second-stage transmission mechanism is an output gear.

8. The locking mechanism according to any one of claims 1 to 3, characterized in that: A deweighting groove is arranged on the gear, and a plurality of deweighting grooves are arranged.

9. The locking mechanism according to claim 8, characterized in that: All the deweighting grooves arranged on the gear are evenly distributed along the circumferential direction.

10. The locking mechanism according to any one of claims 1 to 3, characterized in that: The electromagnet is a bistable electromagnet, which is press-fitted into a cavity provided on the MGU housing through an end cover, and matched with the locking groove position.

11. A method for controlling a locking mechanism according to any one of claims 1 to 10, characterized in that: When the vehicle is parked, the clamping force of the vehicle brake is first set to the first clamping force, the first clamping force is the super-target clamping force, the electromagnet is energized, the locking head extends, and then the gear is controlled to rotate until the locking head contacts the locking surface to complete the locking.

12. The control method of the locking mechanism according to claim 11, characterized in that: When the vehicle is parked, the electromagnet is energized, and the first contact surface on the locking head contacts the end point of the non-locking surface in the target locking groove. Then, the electromagnet remains energized to control the gear to rotate in the first direction, and the gear retracts until the locking head completely enters the target locking groove, and the second contact surface of the locking head contacts the locking surface in the target locking groove, completing the locking action. During this process, the electromagnet remains energized, so that the locking head is always in an extended state, ensuring that the locking head can automatically embed into the locking groove.

13. The control method of the locking mechanism according to claim 11, characterized in that: When the vehicle is parked, the electromagnet is energized, and the first contact surface on the locking head contacts the non-locking surface in the target locking groove. Then, the electromagnet remains energized to control the gear to rotate in a first direction, and the gear retracts until the locking head completely enters the target locking groove, and the second contact surface of the locking head contacts the locking surface in the target locking groove, completing the locking action.

14. The control method of the locking mechanism according to claim 11, characterized in that: When the vehicle is parked, the electromagnet is energized, and the locking head is pushed to the middle position of the target locking groove in the length direction. The electromagnet remains energized to control the gear to rotate in the first direction, and the gear retracts until the locking head completely enters the target locking groove, and the second contact surface of the locking head contacts the locking surface in the target locking groove, completing the locking action.

15. The control method of the locking mechanism according to claim 11, characterized in that: When the vehicle is parked, the electromagnet is energized, and the top end of the locking head is stuck to the edge of the locking surface of the target locking groove. Then, the electromagnet remains energized, and the motor needs to control the gear to rotate in the first direction to make the gear retract, but at this time the gear cannot retract and the motor cannot operate. Then, the gear is controlled to rotate in the second direction for a certain angle, and then the gear is controlled to rotate in the first direction to make the gear retract until the locking head completely enters the target locking groove to complete the locking action.

16. The control method of the locking mechanism according to claim 11, characterized in that: When the vehicle is parked, the electromagnet is energized, and the locking head is pressed against a portion of the gear where no locking groove is provided. Then, the electromagnet remains energized to control the gear to rotate, and the gear moves back until the locking head completely enters the target locking groove, completing the locking action.

17. A method for controlling a locking mechanism according to any one of claims 1 to 10, characterized in that: When the vehicle is parked, the clamping force of the vehicle brake is first set to the second clamping force, the electromagnet is energized, the locking head is extended, and then the motor is controlled to drive the gear to rotate. The locking position is determined by identifying the current of the motor. After the vehicle brake reaches the required target clamping force, the motor ends the action and the locking is completed.

18. The control method of the locking mechanism according to claim 17, characterized in that: When the vehicle is parked, the electromagnet is energized, and the first contact surface on the locking head contacts the end point of the non-locking end surface in the first locking groove. Then, the electromagnet remains energized, and the motor controls the gear to rotate in the second direction, so that the gear rotates until the second locking groove is aligned with the locking head. Then, the motor controls the gear to rotate in the first direction again, so that the gear retracts until the locking head completely enters the second locking groove, thereby completing the locking action.

19. The control method of the locking mechanism according to claim 17, characterized in that: When the vehicle is parked, the electromagnet is energized, and the first contact surface on the locking head contacts the non-locking end surface in the first locking groove. Then, the electromagnet remains energized, and the motor controls the gear to rotate in the second direction. During the rotation of the gear, the non-locking end surface in the first locking groove pushes the locking head out of the first locking groove. When the gear rotates to a state where the second locking groove is aligned with the locking head, the motor controls the gear to rotate in the first direction again, causing the gear to retract until the locking head completely enters the second locking groove, thereby completing the locking action.

20. The control method of the locking mechanism according to claim 17, characterized in that: When the vehicle is parked, the electromagnet is energized, and the locking head is pushed to the middle position in the length direction of the first locking groove. Then, the electromagnet remains energized, and the motor controls the gear to rotate in the second direction. During the rotation of the gear, when the non-locking end surface in the first locking groove contacts the locking head, the locking head is pushed out of the first locking groove. When the gear rotates to a state where the second locking groove is aligned with the locking head, the motor controls the gear to rotate in the first direction again, causing the gear to retract until the locking head completely enters the second locking groove, thereby completing the locking action.

21. The control method of the locking mechanism according to claim 17, characterized in that: When the vehicle is parked, the electromagnet is energized, and the top end of the locking head is stuck to the edge of the locking end face of the first locking groove. Then, the electromagnet remains energized, and the motor controls the gear to rotate in the second direction. During the rotation of the gear, when the non-locking end face in the first locking groove contacts the locking head, it pushes the locking head out of the first locking groove. When the gear rotates to a state where the second locking groove is aligned with the locking head, the motor controls the gear to rotate in the first direction again, causing the gear to retract until the locking head completely enters the second locking groove, thereby completing the locking action.

22. The method for controlling a locking mechanism according to claim 17, characterized in that: When the vehicle is parked, the electromagnet is energized, and the locking head is pressed against a portion of the gear where no locking groove is provided. Then, the electromagnet remains energized, and the motor controls the gear to rotate in the second direction, so that the gear rotates until the locking groove closest to the locking head is aligned with the locking head. Then, the motor controls the gear to rotate in the first direction, so that the gear retracts, until the locking head completely enters the locking groove, thereby completing the locking action.

23. The motor gear unit is characterized by: It comprises the locking mechanism described in any one of claims 1 to 10.

24. A vehicle, characterized in that: Includes the motor gear unit as claimed in claim 23.

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