Parking locking mechanism suitable for electronic mechanical calipers

Abstract

The utility model relates to the field of brake calipers, and discloses a parking locking mechanism suitable for electronic mechanical calipers, which comprises a parking ratchet wheel, an electromagnet assembly, a parking pawl and a parking pawl return torsion spring. The parking ratchet wheel is in interference fit with an output shaft of the brake motor and is driven by the brake motor to rotate; the electromagnet assembly comprises a two-way self-holding electromagnet and a magnetic push rod, the two-way self-holding electromagnet drives the magnetic push rod to stretch out or retract through forward or reverse electrification, the output end of the magnetic push rod is fixedly connected with a parking spring seat, and the parking spring seat is sleeved with a parking compression spring; a parking fork for pressing the parking compression spring is arranged at one end of the parking pawl, a pawl hook meshed with the parking ratchet wheel is arranged at the other end of the parking pawl, and the parking pawl can rotate around a parking pawl rotating shaft; the parking fork is elastically connected with the parking compression spring, and the parking pawl is sleeved with the parking pawl return torsion spring. The parking pawl is always meshed with the ratchet wheel when the magnetic push rod extends out, and the parking re-clamping process is simple and fast.

Description

Technical Field

[0001] This utility model relates to the field of brake calipers, and more particularly to a parking locking mechanism suitable for electromechanical calipers. Background Technology

[0002] With the increasing development of brake-by-wire technology, EMB (Electro-Mechanical Brake System), as the ultimate solution for brake-by-wire technology, needs to simultaneously include both driving and parking functions. Because the transmission scheme of the electro-mechanical brake caliper assembly needs to ensure rapid and precise control of braking force during driving braking, it requires a high-efficiency mechanical structure. A low-efficiency self-locking structure cannot be used. Therefore, the nut-screw transmission mechanism used in existing hydraulic caliper assemblies cannot be used to achieve the vehicle's parking braking function. Thus, an additional parking brake actuator is required. Current technology primarily uses an electromagnet as a power source. When the electromagnet is energized in the positive direction, a magnetic push rod can be retracted or retracted, thereby providing locking and unlocking functions. For example, Chinese invention patent CN 117905879A, entitled "Electromechanical Parking Self-Locking Mechanism, Control Method and Vehicle," describes a method for locking a brake motor. When the brake motor needs to be locked, it maintains a certain braking force. The solenoid valve is energized, and a magnetic push rod moves the pawl to the locking position. At this point, one end of the pawl inserts between two adjacent ratchet teeth. Then, the brake motor is de-energized. Due to the load, the brake motor rotates in the opposite direction, causing the ratchet to engage with the pawl. Finally, the solenoid valve is de-energized, locking the brake motor. However, in this structure, when the brake motor is restricted from forward rotation in the locked state, increasing braking force requires unlocking first, then reversing the brake motor to increase braking force, and then locking the brake motor again via the solenoid valve. This process of unlocking the motor, reversing the rotation to increase braking force, and then relocking results in a response delay and cumbersome steps, hindering the achievement of precise control in a timely manner. Therefore, a mechanical brake locking structure is urgently needed to solve these problems. Utility Model Content

[0003] This invention addresses the shortcomings of existing technologies by providing a parking locking mechanism suitable for electromechanical calipers.

[0004] To solve the above-mentioned technical problems, this utility model achieves its solution through the following technical solution:

[0005] Parking locking mechanisms suitable for electromechanical calipers include parking ratchet, electromagnet assembly, parking pawl, and parking pawl return torsion spring. The parking ratchet is interference-fitted to the output shaft of the brake motor and is driven to rotate by the output shaft of the brake motor. The electromagnet assembly includes a bidirectional self-holding electromagnet and a magnetic push rod. The bidirectional self-holding electromagnet drives the magnetic push rod to extend or retract by forward or reverse energization. After extension or retraction, the magnetic push rod is held in this state by the permanent magnet built into the bidirectional self-holding electromagnet. The output end of the magnetic push rod is fixedly connected to a parking spring seat, and a parking compression spring is fitted on the parking spring seat. The parking pawl has a parking fork at one end that abuts against the parking compression spring, and a pawl hook at the other end that engages with the parking ratchet. The parking pawl can rotate around the parking pawl pivot. The parking fork is elastically connected to the parking compression spring and is subjected to the axial preload of the parking compression spring, giving the parking fork a certain axial holding force. The parking pawl return torsion spring is fitted on the parking pawl and is used to drive the parking pawl to disengage from the parking ratchet. The bidirectional self-holding electromagnet, when energized with its positive and negative terminals, allows the push rod to extend and retract. After de-energization, the push rod remains in its original position with a certain axial holding force. In the parking state, the parking pawl, under the preload of the parking compression spring, maintains a tight engagement with the parking ratchet. This allows the parking ratchet to rotate directly in the direction of increased parking braking force and subsequently re-engage, achieving the parking re-clamping function without requiring the bidirectional self-holding electromagnet to reverse-energize the push rod to disengage and release the parking, waiting for re-parking. After re-parking, the bidirectional self-holding electromagnet is energized again in the forward direction to engage the parking pawl with the parking ratchet and lock the parking. In this structure, when the parking ratchet is driven in the direction of increased braking force, the parking pawl can re-engage with the parking ratchet under the elastic force of the parking compression spring, without the need for the magnetic push rod to reset. It is important to note that the spring force generated by the downward swing of the parking pawl to further compress the parking spring must be less than the axial holding force of the magnetic push rod; otherwise, it will transition to a parking release state. When the vehicle is locked, the brake motor can rotate directly in the forward direction to increase braking force without unlocking and adjusting. This reduces the steps from 3 to 1, shortens the control response time, and effectively avoids the problem of the vehicle rolling backward during the parking and locking process.

[0006] Preferably, the parking lock device includes a housing with an opening on the side and a magnetic push rod located inside the opening for manually changing the magnetic push rod to the parking lock position or the parking release position.

[0007] Preferably, a cover plate is detachably connected to the outside of the opening. The cover plate is connected to the magnetic push rod via a wiring harness, which is used to manually pull the magnetic push rod to the parking release position.

[0008] Preferably, the inner wall of the housing has a protrusion, and one end of the parking pawl return torsion spring abuts against the parking pawl, while the other end abuts against the protrusion of the housing. The preload of the torsion spring optimizes the pawl separation trajectory and reduces mechanical impact during unlocking.

[0009] Preferably, a parking spring retainer is installed at the end of the parking compression spring, and the parking compression spring is compressed and installed between the parking spring seat and the parking spring retainer. The parking spring is compressed and installed between the parking spring seat and the parking spring retainer, and the retainer is limited by a fixing bolt to prevent the parking spring from coming out.

[0010] Preferably, the radial end face of the parking fork is elastically limited by a parking spring pressure ring. The elastic preload of the parking pawl can be changed by adjusting the thickness of the pressure ring or by adjusting the position of the pressure ring.

[0011] Preferably, when the parking fork is re-clamped, the parking fork continues to compress the parking compression spring under the drive of the parking ratchet, and the parking compression spring keeps the parking pawl hook engaged with the parking ratchet.

[0012] This utility model, by adopting the above technical solution, has significant technical effects:

[0013] This utility model uses a bidirectional self-holding electromagnet as the parking lock and release mechanism. By changing its positive and negative energizing directions, the position of the magnetic push rod driven by the bidirectional self-holding electromagnet can be easily adjusted, and the magnetic push rod can be held in the current position by its built-in permanent magnet.

[0014] This invention utilizes the elastic force provided by the compression spring to the parking pawl when it engages with the ratchet, along with the pre-tightening return force of the parking pawl return torsion spring. The parking pawl remains engaged with the ratchet even when the bidirectional self-holding electromagnet's magnetic push rod is extended. Braking force adjustment eliminates the need for unlocking and re-locking steps, resulting in a short response time and solving the problem of cumbersome braking force adjustment steps in existing technologies. The elastic connection between the bidirectional self-holding electromagnet's magnetic push rod and the pawl adapts to the dynamic engagement requirements of the ratchet, simplifying the parking lock and release control process and reducing control precision requirements. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] Figure 2 This is a schematic diagram of the structure of the cover plate of this utility model when it is opened;

[0017] Figure 3 This is a partial structural diagram of the parking lock mechanism;

[0018] Figure 4 This is a schematic diagram of the electromagnet assembly;

[0019] Figure 5 This is a schematic diagram of the structure of the parking ratchet and parking pawl engaging;

[0020] Figure 6 This is a schematic diagram illustrating the working principle of each braking state.

[0021] The parts referred to by the numbers in the above attached diagrams are as follows: 1. Electromagnet assembly; 11. Bidirectional self-holding electromagnet; 111. Magnetic push rod; 12. Parking spring seat; 13. Parking compression spring; 14. Parking spring pressure ring; 15. Fixing bolt; 2. Parking pawl; 21. Parking fork; 22. Pawl hook; 3. Parking pawl return torsion spring; 4. Parking ratchet; 5. Parking pawl shaft; 6. Brake motor; 8. Housing; 81. Protrusion; 82. Opening; 83. Cover plate. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0023] Example 1

[0024] Parking locking mechanisms suitable for electromechanical calipers, such as Figure 1 As shown, the system includes a parking ratchet, an electromagnet assembly, a parking pawl, and a parking pawl return torsion spring 3. The parking ratchet 4 is interference-fitted to the output shaft of the brake motor 6 and is driven to rotate by the output shaft of the brake motor 6. The electromagnet assembly 1 includes a bidirectional self-holding electromagnet 11 and a magnetic push rod 111. The bidirectional self-holding electromagnet 11 drives the magnetic push rod 111 to extend or retract by forward or reverse energizing. After extension or retraction, the magnetic push rod 111 is held in this state by the permanent magnet built into the bidirectional self-holding electromagnet 11. The magnetic push rod can have a certain holding force at both the extension and retraction positions. The output end of the magnetic push rod 111 is fixedly connected to a parking spring seat 12, and a parking compression spring 13 is fitted on the parking spring seat 12.

[0025] like Figure 2 As shown, the parking lock device includes a housing 8, with an opening 82 on the side of the housing 8. A magnetic push rod 111 is located inside the opening 82 and is used to manually change the magnetic push rod 111 to the parking lock position.

[0026] A cover plate 83 is detachably connected to the outside of the opening 82. The cover plate 83 is connected to the magnetic push rod 111 via a wiring harness and is used to manually pull the magnetic push rod 111 to the parking release position. A protrusion 81 is provided on the inner wall of the outer casing 8. One end of the parking pawl return torsion spring 3 abuts against the parking pawl 2, and the other end abuts against the protrusion 81 of the outer casing 8.

[0027] like Figure 3-4As shown, a parking spring retainer 14 is installed at the end of the parking compression spring 13, and the parking compression spring 13 is compressed and installed between the parking spring seat 12 and the parking spring retainer 14.

[0028] like Figure 5 As shown, the parking pawl 2 has a parking fork 21 at one end that abuts against the parking compression spring 13, and a pawl hook 22 at the other end that engages with the parking ratchet 4. The parking pawl 2 can rotate around the parking pawl pivot 5. The parking fork 21 is elastically connected to the parking compression spring 13. The preload of the parking compression spring 13 on the parking fork 21 causes the pawl hook 22 to press down and remain engaged with the ratchet teeth of the parking ratchet 4. The parking pawl return torsion spring 3 is fitted onto the parking pawl 2 and is used to drive the parking pawl 2 to disengage from the parking ratchet 4.

[0029] The parking fork 21 is limited at both radial ends by the parking spring compression ring 14 and the fixing bolt 15, and the parking fork 21 can rotate relative to the parking compression spring 13.

[0030] The radial end face of the parking fork 21 is elastically limited by the parking spring pressure ring 14. The elastic preload of the parking pawl 2 can be changed by adjusting the thickness of the pressure ring 14 or by adjusting the position of the pressure ring 14.

[0031] When the parking brake is clamped again, the parking fork 21 continues to compress the parking compression spring 13 under the action of the parking ratchet 4, and the parking compression spring 13 keeps the parking pawl hook 22 engaged with the parking ratchet 4.

[0032] The parking pawl 2 is driven by the meshing gear transmission group 7, which is connected to the vehicle brake actuator, thereby driving the friction pad to clamp the brake disc or release it.

[0033] like Figure 6 As shown, the working principle is as follows:

[0034] Locking Phase: In one implementation, the brake motor drives the parking ratchet 4 to rotate forward until the braking force reaches the target braking force and is maintained. The bidirectional self-holding electromagnet 11 is energized in the forward direction, and the magnetic push rod 111 extends and drives the parking pawl 2 to engage with the ratchet 4 via the parking compression spring 13. Subsequently, the brake motor is de-energized, and under load, it rotates in the reverse direction, causing the ratchet to press against the pawl, thereby locking the parking pawl 2 against the brake motor shaft. In another implementation: The brake motor drives the ratchet to rotate forward until the braking force reaches the target braking force. Subsequently, the brake motor is de-energized, and under load, it rotates in the reverse direction, causing the ratchet to press against the pawl, thereby locking the parking pawl 2 against the brake motor shaft.

[0035] Re-clamping stage: When increased braking force is needed, the brake motor rotates forward to increase the parking braking force. During this process, the parking ratchet 4 rotates together with the brake motor shaft. The parking pawl 2 is adaptively driven upward by the parking compression spring 13 and the parking pawl return torsion spring 3. Both deform as the ratchet 4 rotates, but at this stage, the forces they provide to the parking pawl 2 are in opposite directions, with the parking compression spring 13 providing a greater elastic force. Therefore, when the ratchet 4 stops rotating, the parking compression spring 13 rebounds, locking the parking pawl 2 back into the groove of the ratchet 4. No additional power-off and power-on adjustments are required for the bidirectional self-holding electromagnet. When the parking brake is locked, if the controller receives a parking brake re-clamp command, it indicates that the braking force is insufficient and the brake motor needs to rotate forward to increase the braking force. Therefore, the controller sends an energizing signal to the electromagnet, which is energized first, causing the magnetic push rod to extend and press against the pawl through the parking brake compression spring. This prevents the pawl from returning to the unlocked position under the tension of the elastic element when the brake motor rotates forward. Then, the controller controls the brake motor to drive the ratchet to rotate forward until the braking force reaches the second target braking force. After that, the controller sends an de-energizing signal to the brake motor, which is de-energized. Under the load, the brake motor rotates in the reverse direction, causing the ratchet to press against the pawl, thus locking the brake motor again.

[0036] When the parking brake is released: the bidirectional self-holding electromagnet is energized in the reverse direction, the magnetic push rod 111 retracts, the brake motor rotates in the forward direction, slightly increasing the parking brake torque. At this time, the reverse force of the parking ratchet on the parking pawl disappears, and the parking pawl 2 moves away from the parking ratchet 4 under the elastic force of the parking pawl return torsion spring 3 and remains in the parking release position. The parking ratchet disengages from the parking pawl to release the parking state.

[0037] Control methods:

[0038] Parking lock control commands:

[0039] S1. The caliper assembly controller receives the parking lock control command.

[0040] S2. The controller sends a power-on signal to the brake motor. After the brake motor is powered on, the controller controls the brake motor to drive the transmission group to rotate in the forward direction until the target braking force is reached and maintained.

[0041] S3. The controller sends an energizing signal to the electromagnet, which is energized in the positive direction. The magnetic push rod pushes the pawl from the unlocked position to the locked position through the parking spring pressure ring, and the parking pawl engages with the parking ratchet.

[0042] S4. The controller sends a power-off signal to the brake motor, the brake motor is de-energized, and after a preset time T1, the controller sends a power-off signal to the electromagnet, the electromagnet is de-energized, the magnetic push rod remains in the extended position, and the parking spring continuously applies elastic force to the parking pawl to ensure that the parking pawl is engaged with the parking ratchet, thus completing the parking lock.

[0043] Parking re-clamp control command:

[0044] S1. The caliper assembly controller receives the parking re-clamp control command.

[0045] S2. The controller sends an energizing signal to the brake motor, which drives the transmission assembly to rotate in the forward direction to achieve the target braking force.

[0046] S3. The controller sends a power-off signal to the brake motor, and the brake motor is de-energized.

[0047] S4. Check if the parking clamping force of the vehicle inspection caliper assembly meets the requirements. If it does, complete the parking process. If it does not, repeat the above steps.

[0048] Parking release control command:

[0049] S1. The caliper assembly controller receives the parking release control command.

[0050] S2. The controller sends a power-on signal to the brake motor. After the brake motor is powered on, the controller controls the brake motor to drive the transmission group to rotate in the forward direction until it is slightly greater than the current parking braking force. At this time, the parking pawl and the parking ratchet are in a non-contact state and remain so.

[0051] S3. The controller sends an energizing signal to the electromagnet, which is energized in reverse. The magnetic push rod moves backward, and the parking pawl moves from the locked position to the unlocked position under the action of the parking pawl return torsion spring.

[0052] S4. The controller sends a power-off signal to the brake motor, the brake motor is de-energized, and the parking brake release is completed.

[0053] Failure protection:

[0054] Manual parking release process: After the electromagnet coil fails, manually open the cover plate 83 fixed to the outer side of the housing 8 and pull it outward. The magnetic push rod is pulled back through the connecting wire harness between the cover plate 83 and the magnetic push rod hole, thus achieving reverse energization of the bidirectional self-holding electromagnet. At this time, the parking pawl moves from the locked position to the unlocked position under the action of the parking return torsion spring 3. At this point, the brake motor applies a slightly larger braking torque, allowing the parking ratchet to disengage from the parking pawl. Without external resistance, the parking pawl return torsion spring can move the parking pawl 2 away from the ratchet 4 to release the parking state.

[0055] Manual parking lock process: First, engage the parking pawl with the parking ratchet, then energize the brake motor to apply braking force. Manually open the cover plate fixed to the outer casing, and use a tool to push the magnetic push rod into the parking lock state, causing the parking pawl to engage with the parking ratchet, thus achieving a forward energization effect on the electromagnet. The brake motor is then energized, and the controller controls the brake motor to drive the transmission assembly to rotate forward until the parking braking force is met. During this process, the parking pawl and parking ratchet remain engaged, thus achieving a bidirectional self-holding electromagnet forward energization effect.

[0056] In the description of this utility model, it should be understood that the terms "center," "length," "width," "thickness," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0057] In summary, the above are merely preferred embodiments of this utility model. All equivalent variations and modifications made within the scope of the claims of this utility model should be covered by this utility model patent.

Claims

1. A parking lock mechanism for an electromechanical caliper, characterized in that, Comprising A parking ratchet (4) is assembled on the output shaft of the brake motor (6) and is driven to rotate by the output shaft of the brake motor (6); An electromagnet assembly (1) comprises a bidirectional self-holding electromagnet (11) and a magnetic push rod (111), the bidirectional self-holding electromagnet (11) drives the magnetic push rod (111) to extend or retract through forward or reverse power supply, the magnetic push rod (111) is kept in the state after extension or retraction by the built-in permanent magnet of the bidirectional self-holding electromagnet (11), the output end of the magnetic push rod (111) is fixedly connected with a parking spring seat (12), and the parking spring seat (12) is sleeved with a parking compression spring (13); A parking pawl (2) is provided with a parking fork (21) abutting against the parking compression spring (13) at one end and a pawl hook (22) engaging with the parking ratchet (4) at the other end, and the parking pawl (2) can rotate around a parking pawl rotating shaft (5); the parking fork (21) is elastically connected with the parking compression spring (13), and the pre-tightening force of the parking compression spring (13) on the parking fork (21) makes the pawl hook (22) press downward and keep engagement with the ratchet teeth of the parking ratchet (4); A parking pawl return torsional spring (3) is sleeved on the parking pawl (2) and is used to drive the parking pawl (2) to disengage from the parking ratchet (4).

2. The parking lock mechanism suitable for use in an electromechanical caliper according to claim 1, characterized in that: The parking locking device comprises an outer shell (8), the outer shell (8) is provided with an opening (82) at the side, the magnetic push rod (111) is located inside the opening (82), and the magnetic push rod (111) is used to manually change the parking locking device to a parking locking position or a parking releasing position.

3. The parking lock mechanism suitable for use in an electromechanical caliper according to claim 2, characterized in that: A cover plate (83) is detachably connected outside the opening (82), the cover plate (83) is connected with the magnetic push rod (111) through a wire harness, and the cover plate (83) is used to manually pull the magnetic push rod (111) to the parking releasing position.

4. The parking lock mechanism suitable for use in an electromechanical caliper according to claim 1, characterized in that: The inner wall of the outer shell (8) is provided with a protruding portion (81), one end of the parking pawl return torsional spring (3) abuts against the parking pawl (2), and the other end abuts against the protruding portion (81) of the outer shell (8).

5. The parking lock mechanism suitable for use in an electromechanical caliper according to claim 1, characterized in that: The end of the parking compression spring (13) is provided with a parking spring pressing ring (14), and the parking compression spring (13) is compressed and installed between the parking spring seat (12) and the parking spring pressing ring (14).

6. The parking lock mechanism suitable for use in an electromechanical caliper according to claim 5, characterized in that: The radial end face of the parking fork (21) is elastically limited by the parking spring pressing ring (14), the elastic pre-tightening force of the parking pawl (2) is changed by adjusting the thickness of the pressing ring (14) or by adjusting the position of the pressing ring (14).

7. The parking lock mechanism suitable for use in an electromechanical caliper according to claim 6, characterized in that: When the parking fork (21) is parked again, the parking fork (21) continues to compress the parking compression spring (13) under the driving of the parking ratchet (4), and the parking compression spring (13) keeps the pawl hook (22) engaged with the parking ratchet (4).

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