Electronic mechanical brake for automobile and parking release control method

Abstract

The invention discloses an automobile electronic mechanical brake and a parking release control method. The automobile electronic mechanical brake structurally comprises a shell. The brake driving motor is installed on the side portion of one end of a shell of the electronic mechanical brake, a caliper executing mechanism is further arranged on one side of the shell and comprises a caliper support and a caliper body, the caliper body is arranged in the caliper support and connected with the shell, a lead screw assembly is installed in the caliper body, one end of the lead screw assembly is connected with a movable friction plate, and the other end of the lead screw assembly is connected with the brake driving motor. A gear transmission mechanism is installed in the shell to enable the lead screw assembly to be in transmission connection with a driving main shaft of the brake driving motor, a ratchet wheel and pawl locking assembly matched with the driving main shaft is further arranged in the shell and comprises a ratchet wheel installed on the driving main shaft, and a pawl matched with the ratchet wheel is arranged on one side of the ratchet wheel. The pawl is driven by a locking motor on the shell to rotate. The problem that a locking return mechanism of an existing electronic mechanical brake is poor in durability and reliability can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of automobile brakes, in particular to an electronic mechanical brake for an automobile and a method for releasing parking control. Background Art

[0002] With the development of intelligent automobile industry, people's functional demand for intelligent driving application technology is becoming stronger and stronger. As one of the core technologies of autonomous driving, wire control technology has also entered a rapid development stage. As an important part of wire control technology, wire control braking has also ushered in opportunities and challenges of rapid development. Most of the braking products on the current market are electro-hydraulic brake products, not pure wire control technology products. However, electro-hydraulic brake products have their own defects, such as heavy weight, complex structure, need to rely on brake pipes, and need to replace brake fluid regularly; and the four wheels of the car cannot be controlled independently, and the braking force cannot be distributed on demand; at the same time, there is also a problem of response speed. The driver needs to step on the pedal to push the brake fluid. After the brake fluid flows through the brake pipe, the brake can be braked. The corresponding response speed is slow and the braking time is long.

[0003] The electronic mechanical braking system mainly realizes braking under purely mechanical conditions. For the hotly developing new energy vehicles, the lack of brake fluid reduces the weight of the vehicle while being pollution-free, and can better recover energy. The mechanical structure required in the mechanical braking system technology is simple, the cost is lower, the software control is more convenient, the response speed is faster, and the four-wheel independent control can cope with various complex road conditions, and can meet various stringent standards and market evaluation system requirements for automobiles, promoting the rapid development of active safety technology for automobiles.

[0004] As a braking system, the electronic mechanical brake system needs to realize the conventional braking function and the parking function. In the mechanical structure, the motor drives the gear and other deceleration and torque-increasing mechanisms, and then the conversion mechanism is used to convert the rotary motion into a linear motion structure, and the conversion mechanism is required to be able to cope with a high number of parking durability. However, since the ball screw, planetary roller screw and other conversion mechanisms on the market do not have self-locking performance, it is necessary to add an additional parking lock mechanism. Since the self-locking solutions used in the market mostly use springs and other locking return mechanisms, the durability and reliability cannot be guaranteed. Therefore, the electronic mechanical brake needs to have a power execution structure of the parking lock mechanism to solve the above problems. In addition, the gear transmission structure of the existing electronic mechanical brake occupies a relatively large volume, the output torque is limited, and it is impossible to achieve high-intensity braking conditions. Summary of the invention

[0005] The invention provides an electronic mechanical brake for an automobile and a parking release control method, which can solve the problems of complex structure, poor durability and reliability of the locking return mechanism of the existing electronic mechanical brake.

[0006] To achieve the above-mentioned purpose, in a first aspect, the present invention provides the following technical solutions: an electronic mechanical brake for an automobile, the structure of which includes a housing; a brake drive motor, which is installed on one end side of the housing of the electronic mechanical brake, and a caliper actuator is also provided on one side of the housing, the caliper actuator includes a caliper bracket and a caliper body which is arranged inside the caliper bracket and connected to the housing, a screw rod assembly is installed inside the caliper body, one end of the screw rod assembly is connected to a dynamic friction plate, a static friction plate is installed at a position on the inner side of the caliper bracket corresponding to the dynamic friction plate, and a gear transmission mechanism is installed inside the housing to connect the screw rod assembly to the driving spindle of the brake drive motor The housing is connected to the transmission, and a ratchet pawl locking assembly cooperating with the driving main shaft is also arranged inside the housing, and the ratchet pawl locking assembly includes a ratchet mounted on the driving main shaft, and a pawl matching with the ratchet is arranged on one side of the ratchet, and the pawl is driven to rotate by a locking motor on the housing so that the end of the pawl is engaged with or disengaged from the ratchet teeth on the ratchet. A PCBA board is installed inside the housing, and an angle sensor device cooperating with the PCBA board is installed at the end of the main shaft. By setting a locking structure of the ratchet and the pawl, the pawl is driven to rotate by the locking motor, and cooperates with the angle sensor device to realize precise control of the locking structure, which is stable and reliable.

[0007] Preferably, the gear transmission mechanism includes an actuator gear installed on the driving main shaft, an idler gear installed in the middle of the housing and meshing with the actuator gear, and a double gear meshing with the idler gear, the double gear includes a large gear and a small gear arranged coaxially, a planetary gear carrier is installed on the axial side of the double gear, a plurality of planetary gears are installed around the circumference of the planetary gear carrier, a ring gear is installed on the radial outer side of the planetary gear carrier, the planetary gears are meshed with the pinion gear and the ring gear at the same time, an output connecting groove is provided at one axial end of the planetary gear carrier, the output connecting groove is connected to the input end of the screw assembly, the gear transmission mechanism has a compact structure, the planetary gear carrier can protect the gears inside and on the upper side, and the planetary gear carrier is directly used for power output, the torque is relatively large, the transmission is smooth, and the friction is relatively small.

[0008] Preferably, the planetary gear carrier includes an upper fixed plate and a lower fixed plate which are arranged vertically, and a plurality of fixed shafts for fixing the planetary gear sleeves are arranged around the circumference between the upper fixed plate and the lower fixed plate, a through hole for the pinion gear to extend into is arranged in the middle of the upper fixed plate, a boss is arranged on one axial side of the lower fixed plate, and the output connecting groove is arranged on the end face of the boss, the upper fixed plate and the lower fixed plate can protect the planetary gears and position the double gears at the same time to ensure the accuracy of transmission, the boss can be used as an output shaft, and can be transmitted to the screw assembly through the output connecting groove to achieve stable and rapid braking.

[0009] Preferably, a driving gear is installed on the main shaft of the locking motor, and the driving gear is meshed with the transmission teeth on the edge of the pawl. A locking fixing frame is installed on the side of the execution gear inside the shell, and the locking motor is installed on the locking fixing frame. The locking fixing frame can install and fix the locking motor, and the locking fixing frame can leave enough space for the setting of the pawl and the driving gear.

[0010] Preferably, the angle sensor device includes a mounting block installed at the end of the spindle, a magnetic pole is installed at the end of the mounting block, a magnetic induction chip is installed at a position corresponding to the magnetic pole on the PCBA board, and the distance between the magnetic pole and the magnetic induction chip is obtained through simulation, so that the rotation of the spindle can be controlled in real time.

[0011] Preferably, the screw assembly includes a screw and a nut sleeved on the outside of the screw, a plurality of ball bearings are arranged between the screw and the nut, one axial end of the nut is connected to the dynamic friction plate, and one axial end of the screw is provided with a connecting shaft that cooperates with the gear transmission mechanism. The gear transmission mechanism can drive the screw to rotate with high torque, which is converted into axial movement of the nut, so that the dynamic friction plate and the static friction plate can move relative to each other to achieve braking of the vehicle.

[0012] Preferably, a thrust bearing is sleeved on the outer side of one end of the screw rod close to the connecting plug shaft, and a force sensor is installed in axial contact with one end of the thrust bearing. The force sensor is used to detect the retraction force between the screw rod and the caliper body. The current retraction force data can be accurately read during operation. The current state of the motor actuator can be fed back by monitoring the retraction force. The force sensor and the brake drive motor current verify each other, thereby accurately controlling the movement stroke of the screw rod and further improving the safety factor.

[0013] Preferably, at least one anti-rotation groove is arranged around the circumference on the end surface where the nut is connected to the dynamic friction plate, and an anti-rotation boss embedded with the corresponding anti-rotation groove is arranged on the outer wall of the dynamic friction plate. The anti-rotation groove and the anti-rotation boss are used to prevent the nut from rotating with the screw rod, thereby playing an anti-rotation role and having a reliable structure.

[0014] Preferably, the housing comprises a lower housing, an upper housing and an upper cover mounted on the side of the upper housing, the upper housing and the lower housing are spliced ​​up and down, the PCBA board is mounted in the space between the upper cover and the upper housing, the PCBA board can be installed and fixed separately, and the gear transmission mechanism can effectively utilize the internal structure of the housing. The brake drive motor is mounted on the lower housing, and the locking motor is arranged through the upper housing, which is convenient for wiring the locking motor and connecting it to the ECU of the vehicle.

[0015] In the second aspect, the present invention also provides a method for controlling the release of parking of an electronic mechanical brake. The specific method is that when the brake drive motor as described in the first aspect receives a signal to release the parking brake, the brake drive motor is first reversed. After the reversal, there is no torque between the ratchet and the pawl. At this time, the locking motor drives the pawl to rotate to move it away from the ratchet, thereby releasing the parking lock device.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The structure is simple. By setting a locking structure of a ratchet and a pawl, the pawl is driven to rotate by a locking motor. In cooperation with the angle sensor device, precise control of the locking structure can be achieved. When the pawl is stuck on the ratchet, the parking locking action is completed. When the locking motor is powered off, the current parking state can be maintained, which is stable and reliable. When in the parking release state, the locking motor drives the pawl away from the ratchet, and the pawl will not vibrate from the released state to the locked state due to vibration or other conditions. The gear transmission mechanism used is compact in structure, and the planetary gear frame can protect the gears inside and on the upper side, and the planetary gear frame is directly used for power output, with relatively large torque, smooth transmission and relatively small friction. The structure of the screw assembly is reliable. By setting a force sensor, the current retraction force data can be accurately read during operation. The current state of the motor actuator can be fed back through the monitored retraction force. The force sensor and the brake drive motor current verify each other, thereby accurately controlling the movement stroke of the screw and further improving the safety factor. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional cross-sectional structural diagram of the present invention;

[0019] Figure 2 It is a side cross-sectional structural diagram of the present invention;

[0020] Figure 3 It is a partial cross-sectional enlarged view of the present invention;

[0021] Figure 4 It is a three-dimensional structural diagram of the internal structure of the present invention;

[0022] Figure 5 It is an overall exploded three-dimensional structural diagram of the present invention;

[0023] Figure 6 It is a three-dimensional structural diagram of the ratchet pawl locking assembly of the present invention;

[0024] Figure 7 It is a three-dimensional structural diagram of the ratchet pawl locking assembly of the present invention;

[0025] Figure 8 It is a schematic diagram of the locked state of the ratchet pawl of the present invention;

[0026] Fig. 9 This is a schematic diagram of the ratchet pawl unlocking state of the present invention;

[0027] Fig.10 is a schematic structural diagram of an angle sensor device of the present invention;

[0028] Fig.11 It is an exploded three-dimensional structural diagram of the gear transmission mechanism of the present invention;

[0029] Fig.12 is a three-dimensional structural diagram of the planetary gear carrier of the present invention;

[0030] Fig.13 It is a three-dimensional cross-sectional structural diagram of the screw rod assembly of the present invention;

[0031] Fig.14 It is a diagram of the cooperation between the screw rod assembly and the dynamic friction plate of the present invention;

[0032] Reference numerals:

[0033] 1. Brake drive motor, 11. Main shaft, 12. Limit pin, 3. Gear transmission mechanism, 31. Executing gear, 32. Idle gear, 33. Double gear, 331. Large gear, 332. Small gear, 34. Top bearing, 35. Planetary gear carrier, 351. Fixed shaft, 352. Lower fixed plate, 353. Boss, 354. Output connecting groove, 355. Raised table, 356. Upper fixed plate, 36. Bottom bearing, 37. Ring gear, 38. Planetary gear, 4. Ratchet pawl locking assembly, 41. Ratchet, 42. Locking motor, 43. Pawl, 431. Ratchet gear end, 432. Ratchet claw end, 44, driving gear, 45, locking bracket, 5, housing, 51, upper cover, 52, upper housing, 53, lower housing, 6, screw assembly, 61, nut, 611, anti-rotation groove, 62, screw, 63, ball, 64, thrust bearing, 65, force sensor, 66, bushing, 67, retaining spring, 68, connecting shaft, 69, piston end plate, 7, caliper actuator, 71, caliper body, 72, caliper bracket, 73, static friction plate, 74, dynamic friction plate, 741, anti-rotation boss, 8, PCBA board, 9, angle sensor device, 91, magnetic induction chip, 92, magnetic pole, 93, mounting block. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0035] like Figure 1-14As shown, the present invention provides the following technical solutions to solve the problems of poor durability and reliability of the locking return mechanism of the existing electronic mechanical brake: an electronic mechanical brake for automobile, the structure of which includes a housing 5; a brake driving motor 1, which is installed on one end side of the housing 5 of the electronic mechanical brake, and a caliper actuator 7 is also provided on one side of the housing 5, the caliper actuator 7 includes a caliper bracket 72 and a caliper body 71 arranged inside the caliper bracket 72 and connected to the housing 5, a screw rod assembly 6 is installed inside the caliper body 71, one end of the screw rod assembly 6 is connected to a dynamic friction plate 74, a static friction plate 73 is installed at a position corresponding to the dynamic friction plate 74 on the inner side of the caliper bracket 72, and a gear transmission mechanism 3 is installed inside the housing 5 to connect the screw rod assembly 6 with the brake driving motor 1 The housing 5 is connected to the driving spindle 11 for transmission, and a ratchet pawl locking assembly 4 cooperating with the driving spindle 11 is further provided inside the housing 5. The ratchet pawl locking assembly 4 includes a ratchet 41 mounted on the driving spindle 11, and a pawl 43 matching with the ratchet 41 is provided on one side of the ratchet 41. The pawl 43 is driven to rotate by a locking motor 42 on the housing 5, so that the end of the pawl 43 is engaged with or disengaged from the ratchet teeth on the ratchet 41. A PCBA board 8 is installed inside the housing 5, and an angle sensor device 9 cooperating with the PCBA board 8 is installed at the end of the spindle 11. By setting a locking structure of the ratchet 41 and the pawl 43, the pawl 43 is driven to rotate by the locking motor 42, and cooperates with the angle sensor device 9 to achieve precise control of the locking structure, which is stable and reliable.

[0036] Specifically, the brake drive motor 1 is the main power of the brake. Its output can be changed through the gear transmission mechanism 3, and the torque is increased and transmitted to the screw assembly 6, which converts the power into the movement of the dynamic friction plate 74. When the dynamic friction plate 74 and the static friction plate 73 are close to each other, the brake disc on the wheel can be held tightly to achieve braking; when the dynamic friction plate 74 and the static friction plate 73 are away from each other, the brake is released. The output torque of the main shaft 11 of the brake drive motor 1 is relatively low, so the ratchet pawl locking assembly 4 is set to cooperate with the main shaft 11, which can reduce the impact and force on the ratchet pawl locking assembly 4.

[0037] Specifically, when the pawl 43 acts on the ratchet 41, the ratchet 41 stops moving and remains locked, the driving spindle 11 also stops moving, and the mating gear transmission mechanism 3 also stops moving. In theory, the entire gear transmission mechanism parts can be locked.

[0038] Among them, a driving gear 44 is installed on the main shaft of the locking motor 42, and the driving gear 44 is meshed with the transmission teeth on the edge of the ratchet 43. A locking fixing frame 45 is installed on one side of the execution gear 31 inside the shell 5, and the locking motor 42 is installed on the locking fixing frame 45. The locking fixing frame 45 can install and fix the locking motor 42, and at the same time, the locking fixing frame 45 can leave enough space for the setting of the ratchet 43 and the driving gear 44.

[0039] The number of ratchet teeth of the ratchet 41 is as large as possible in terms of the technical requirements of mechanical strength, so as to control the parking stroke and improve the accuracy of controlling the parking force. The pawl 43 has two working states: the ratchet pawl parking lock state and the ratchet pawl release lock state. The corresponding pawl 43 is at two positioning points, one positioning point is the locking state of the pawl 43 and the ratchet 41, and the other positioning point is the pawl 43 away from the ratchet 41, and the pawl limit end on the housing 5 acts as a limit; the angle of the two pawl 43 states is 30°, and the angle size is set according to two aspects. One is to ensure the basis of being completely away, such as the pawl 43 will not return to the locked state when vibrating, and the other is that the distance between the pawl 43 and the ratchet 41 is moderate, and the action time is moderate. If the pawl 43 travels too far from the locking port to the release end of the two positioning points, it will cause the parking action time to be too long. The number of teeth of the pawl gear end 431 on the pawl 43 can be designed according to the initial and final states of the two positioning points of the pawl, and the invalid gear features without meshing requirements outside the stroke can be removed, reducing material consumption and processing costs.

[0040] The pawl claw end 432 of the pawl 43 acts on the ratchet teeth of the ratchet wheel 41 to achieve parking locking and release. Due to the requirement of parking durability, there is a wear problem of the ratchet wheel 41 and the pawl 43, so a hard layer can be plated on the contact surface of the pawl 43 with the ratchet wheel 41 to increase wear resistance.

[0041] In addition, in this embodiment, the mechanical parts are protected by software logic control. When the pawl 43 is constantly moving away, the contact area between the pawl 43 and the ratchet 41 becomes smaller and smaller, the stress becomes more and more concentrated, and the pawl 43 and the ratchet 41 are more and more susceptible to damage, especially when the parking endurance times are large, the damage is greater. Therefore, on the basis of selecting high-strength mechanical performance materials as much as possible, the ratchet 41 and the pawl 43 are protected from damage through software control logic. After receiving the release parking brake signal, the brake drive motor 1 is reversed first. After the reversal, there is no torque between the pawl 43 and the ratchet 41. At this time, the locking motor 42 rotates, driving the driving gear 44 to mesh with the pawl gear end 431, driving the pawl claw end 431 away from the ratchet 41 from the locked state to the release state of the pawl limit end, the pawl 43 can be easily released from parking, and the ratchet 41 and the pawl 43 are not mechanically damaged, ensuring the safety characteristics.

[0042] In this embodiment, the gear transmission mechanism 3 includes an execution gear 31 installed on the driving main shaft 11, an idler gear 32 installed in the middle of the housing 5 and meshing with the execution gear 31, and a double gear 33 meshing with the idler gear 32. The double gear 33 includes a large gear 331 and a small gear 332 arranged coaxially. A planetary gear carrier 35 is installed on one axial side of the double gear 33. A plurality of planetary gears 38 are installed around the circumference of the planetary gear carrier 35. A ring gear 37 is installed on the radial outer side of the planetary gear carrier 35. The planetary gear 38 meshes with the small gear 332 and the ring gear 37 at the same time. An output connecting groove 354 is provided at one axial end of the planetary gear carrier 35. The output connecting groove 354 is connected to the input end of the screw assembly 6. The gear transmission mechanism 3 has a compact structure. The planetary gear carrier 35 can protect the gears inside and on the upper side thereof, and the planetary gear carrier 35 is directly used for power output, with relatively large torque, smooth transmission and relatively small friction.

[0043] The output connecting groove 354 can be a spline groove, and the corresponding input end of the screw assembly 6 is also a spline shaft. The gear transmission mechanism 3 is flat as a whole, and the brake drive motor 1 and the output connecting groove 354 are respectively arranged at both ends of the shell 5, so the gear transmission mechanism 3 can transmit the power of the brake drive motor 1 to the output connecting groove 354, leaving more space for the installation of other components on the braking device.

[0044] In this embodiment, if Figure 11-12As shown, the planetary gear carrier 35 includes an upper fixed plate 356 and a lower fixed plate 352 which are arranged in an upper and lower manner. A plurality of fixed shafts 351 for the planetary gears 38 to be sleeved and fixed are arranged around the circumference between the upper fixed plate 356 and the lower fixed plate 352. A through hole for the pinion 332 to extend into is arranged in the middle of the upper fixed plate 356. A boss 353 is arranged on one axial side of the lower fixed plate 352. The output connecting groove 354 is arranged on the end face of the boss 353. The upper fixed plate 356 and the lower fixed plate 352 can protect the planetary gears 38 and position the duplex gears 33 at the same time to ensure the accuracy of transmission. The boss 353 can be used as an output shaft and can be transmitted to the screw assembly 6 through the output connecting groove to achieve stable and rapid braking.

[0045] Among them, the upper fixed plate 356 and the lower fixed plate 352 can protect the planetary gear 38 and position the double gear 33 to ensure the accuracy of transmission. The boss 353 can be used as an output shaft and can be transmitted to the braking components of the braking system through the output connecting groove 354 to achieve stable and rapid braking. The upper fixed plate 356 and the lower fixed plate 352 at both ends of the fixed shaft 351 are both provided with raised table surfaces 355, and the two ends of the planetary gear 38 are provided with convex surfaces in contact with the raised table surfaces 355, which can reduce the friction when the planetary gear 38 rotates.

[0046] In addition, if Figure 3 As shown, a bottom bearing 36 is arranged on the outer side of the boss 353, and a top bearing 34 is sleeved on the outer side of the upper end of the central axis of the double gear 33, which can ensure the smoothness of the rotation of the double gear 33 and the planetary gear carrier 35, reduce friction resistance, and support and fix the planetary gear carrier 35. At the same time, in order to prevent the ring gear 37 from rotating, a plurality of limit pins 12 are arranged on the outer circumferential edge of the ring gear 37 to be clamped and fixed with the housing 5, and the limit pins 12 can effectively prevent the ring gear 37 from rotating and position, reducing the use of fasteners.

[0047] In this embodiment, the angle sensor device 9 includes a mounting block 93 installed at the end of the spindle 11, a magnetic pole 92 is installed at the end of the mounting block 93, a magnetic induction chip 91 is installed at a position corresponding to the magnetic pole 92 on the PCBA board 8, and the distance between the magnetic pole 92 and the magnetic induction chip 91 is obtained through simulation, so that the rotation of the spindle 11 can be controlled in real time.

[0048] In this embodiment, if Figure 13-14As shown, the screw assembly 6 includes a screw 62 and a nut 61 sleeved on the outside of the screw 62, a plurality of balls 63 are arranged between the screw 62 and the nut 61, one axial end of the nut 61 is connected to the dynamic friction plate 74, and one axial end of the screw 62 is provided with a connecting shaft 68 that is plugged in with the gear transmission mechanism 3. The gear transmission mechanism 3 can drive the screw 62 to rotate with high torque, which is converted into axial movement of the nut 61, so that the dynamic friction plate 74 and the static friction plate 73 can move relative to each other to achieve braking of the vehicle, wherein the connecting shaft 68 is plugged in with the output connecting groove 354, and a spline shaft can be used. A retaining spring 67 can be axially sleeved on one side of the connecting shaft 68, and the retaining spring 67 is located on the outer side of the end face of the caliper body 71, and can axially limit the connecting shaft 68. At the same time, a bushing 66 is also sleeved on one side of the connecting shaft 68, and the bushing 66 cooperates with the caliper body 71 and can be used as a bearing.

[0049] Among them, a thrust bearing 64 is sleeved on the outer side of one end of the screw rod 62 close to the connecting plug shaft 68, and a force sensor 65 is installed in axial contact with one end of the thrust bearing 64. The force sensor 65 is used to detect the retraction force between the screw rod 62 and the caliper body 71. The current retraction force data can be accurately read during the working process. The current state of the motor actuator can be fed back by monitoring the retraction force. The force sensor 65 and the brake drive motor 1 current verify each other, and then the movement stroke of the screw rod 62 is accurately controlled to further improve the safety factor. Among them, one side of the thrust bearing 64 is in contact with the force sensor 65, and the force sensor 65 and the caliper body 71 are anti-rotation matched. The side of the thrust bearing 64 in contact with the force sensor 65 will not rotate, and the other side is connected to the screw rod 62 and can rotate with the screw rod 62.

[0050] In addition, a hole may be opened on the end surface of the nut 61 and a piston end plate 69 may be installed to facilitate maintenance and oiling of the inside of the nut 61 .

[0051] like Fig.14 As shown, at least two anti-rotation grooves 611 are arranged around the circumference on the end surface where the nut 61 is connected to the dynamic friction plate 74, and an anti-rotation boss 741 embedded with the corresponding anti-rotation groove 611 is arranged on the outer wall of the dynamic friction plate 74. The anti-rotation groove 611 and the anti-rotation boss 741 are used to prevent the nut 61 from rotating with the screw rod 62, thereby playing an anti-rotation role and having a reliable structure.

[0052] In this embodiment, if Figure 5As shown, the housing 5 includes a lower housing 53, an upper housing 52 and an upper cover 51 installed on the side of the upper housing 52. The upper housing 52 and the lower housing 53 are spliced ​​up and down, and the PCBA board 8 is installed in the space between the upper cover 51 and the upper housing 52. The PCBA board 8 can be installed and fixed separately, and the gear transmission mechanism 3 can effectively utilize the internal structure of the housing 5. Among them, the brake drive motor 1 is installed on the lower housing 53, and the locking motor 42 is arranged through the upper housing 52, which is convenient for wiring the locking motor 42 and connecting it to the ECU of the car.

[0053] In this embodiment, the specific brake release implementation process is as follows:

[0054] When the brake drive motor 1 is powered on and rotates counterclockwise (from b to a), the actuator gear 31 on the driving main shaft 11 rotates, the idler gear 32 meshing with it rotates, the double gear 33 meshing with the idler gear 32 rotates, and the large gear 331 and the small gear 332 rotate synchronously. The small gear 332 acts as a sun gear, driving the three planetary gears 38 to transmit. At the same time, the planetary gears 38 are meshed with the fixed gear ring 37 on the housing 5 for transmission. While the planetary gears 38 rotate, the boss 353 on the planetary gear carrier 35 also rotates synchronously. The output connection groove 354 drives the entire screw 62 to rotate synchronously, causing the screw 62 to move axially, and the dynamic friction plate 74 moves away from the static friction plate 73 until the parking force is released and returns to the specified position, and the motor stops working.

[0055] At the same time, during the braking process, the rotation angle of the angle sensor device 9 is monitored in real time, and the force of the force sensor 65 is monitored to control the rotation of the screw rod 62 and the axial return amount of the nut 61 to prevent the nut 61 from retreating too much or too little to affect the next braking effect.

[0056] The specific parking implementation process is as follows:

[0057] When the brake drive motor 1 rotates clockwise (a to b), the execution gear 31 installed on the drive spindle 11 rotates, and the entire gear transmission mechanism 3 realizes the deceleration and torque increase effect through the gear group meshing transmission, and then the torque is converted into linear motion through the screw assembly 6, pushing the dynamic friction plate 74 in the caliper actuator 7 to rub the static friction plate 73. When the specified clamping force is reached, the current state needs to be locked. Specifically, the locking motor 42 receives the control signal, drives the gear 44 to rotate, drives the ratchet gear end 431 meshing with it to rotate, and realizes the deceleration and torque increase effect, while driving the ratchet claw end 432 to rotate from the release state to the locked state. At this time, the ratchet 43 clamps the ratchet wheel 41, completing the parking lock action, and the locking motor 42 is powered off to maintain the current parking state.

[0058] The specific implementation process of releasing parking is as follows:

[0059] When the parking brake release signal is received, the brake drive motor 1 is controlled by software to reverse (b to a), driving the ratchet 41 on the main shaft 11 to rotate away from the ratchet claw end 432 of the ratchet 43, and then the locking motor 42 rotates, driving the driving gear 44 to rotate synchronously, driving the ratchet gear end 431 meshing with it to rotate, achieving deceleration and torque increase while driving the ratchet claw end 432 to rotate from the locked state to the released state at the limit end of the shell. At this time, the ratchet 43 is away from the ratchet 41, completing the parking release action. The locking motor 42 is powered off to maintain the current parking state. When the vehicle is driving, it is in the parking release state, and the ratchet 43 is away from the ratchet 41. However, due to vibration and other conditions, the ratchet 43 may vibrate from the released state to the locked state, causing a dangerous situation. Therefore, the locking motor 42 is controlled by an H-bridge direct motor circuit to maintain the driving gear 44 from shaking, and the locking motor 42 is controlled by the H-bridge with a self-locking function.

[0060] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0061] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0062] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0063] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. An electromechanical brake for a vehicle, characterized in that: Its structure includes: Housing (5); A brake drive motor (1) is mounted on one side of a housing (5) of an electronic mechanical brake. A caliper actuator (7) is also arranged on one side of the housing (5). The caliper actuator (7) comprises a caliper bracket (72) and a caliper body (71) arranged inside the caliper bracket (72) and connected to the housing (5). A screw assembly (6) is installed inside the caliper body (71). One end of the screw assembly (6) is connected to a dynamic friction plate (74). A static friction plate (73) is installed on the inner side of the caliper bracket (72) at a position corresponding to the dynamic friction plate (74). A gear transmission mechanism (3) is installed inside the housing (5) to connect the screw assembly (6) with the brake drive motor (1). The housing (5) is connected to the driving spindle (11) by transmission, and a ratchet pawl locking assembly (4) cooperating with the driving spindle (11) is also arranged inside the housing (5), and the ratchet pawl locking assembly (4) comprises a ratchet (41) mounted on the driving spindle (11), and a pawl (43) matching with the ratchet (41) is arranged on one side of the ratchet (41), and the pawl (43) is driven to rotate by a locking motor (42) on the housing (5), so that the end of the pawl (43) is engaged with or disengaged from the ratchet teeth on the ratchet (41), and a PCBA board (8) is installed inside the housing (5), and an angle sensor device (9) cooperating with the PCBA board (8) is installed at the end of the spindle (11).

2. The electromechanical brake for automobile according to claim 1, characterized in that: The gear transmission mechanism (3) comprises an actuator gear (31) mounted on a driving main shaft (11), an idler gear (32) mounted in the middle of a housing (5) and meshing with the actuator gear (31), and a double gear (33) meshing with the idler gear (32); the double gear (33) comprises a large gear (331) and a small gear (332) arranged coaxially; a planetary gear carrier (35) is mounted on an axial side of the double gear (33); a plurality of planetary gears (38) are mounted on the planetary gear carrier (35) around a circumference; a ring gear (37) is mounted on a radially outer side of the planetary gear carrier (35); the planetary gears (38) mesh with the small gear (332) and the ring gear (37) at the same time; an output connecting groove (354) is arranged on an axial end of the planetary gear carrier (35); the output connecting groove (354) is connected to an input end of the screw assembly (6).

3. The electromechanical brake for automobile according to claim 2, characterized in that: The planetary gear carrier (35) comprises an upper fixed plate (356) and a lower fixed plate (352) which are arranged vertically. A plurality of fixed shafts (351) for the planetary gears (38) to be sleeved and fixed are arranged around the circumference between the upper fixed plate (356) and the lower fixed plate (352). A through hole for the pinion gear (332) to extend into is arranged in the middle of the upper fixed plate (356). A boss (353) is arranged on one axial side of the lower fixed plate (352). The output connecting groove (354) is arranged on the end surface of the boss (353).

4. The electromechanical brake for automobile according to claim 1, characterized in that: A driving gear (44) is mounted on the main shaft of the locking motor (42), and the driving gear (44) is meshed with a transmission tooth on the edge of the ratchet (43). A locking bracket (45) is mounted on one side of the execution gear (31) inside the housing (5), and the locking motor (42) is mounted on the locking bracket (45).

5. The electromechanical brake for automobile according to claim 1, characterized in that: The angle sensor device (9) comprises a mounting block (93) mounted on the end of the main shaft (11), a magnetic pole (92) being mounted on the end of the mounting block (93), and a magnetic induction chip (91) being mounted on the PCBA board (8) at a position corresponding to the magnetic pole (92).

6. The electromechanical brake for automobile according to claim 1, characterized in that: The screw assembly (6) comprises a screw (62) and a nut (61) sleeved on the outside of the screw (62), a plurality of balls (63) are arranged between the screw (62) and the nut (61), one axial end of the nut (61) is connected to a moving friction plate (74), and one axial end of the screw (62) is provided with a connecting shaft (68) which is plugged into the gear transmission mechanism (3).

7. The electromechanical brake for automobile according to claim 6, characterized in that: A thrust bearing (64) is sleeved on the outer side of one end of the screw rod (62) close to the connecting plug shaft (68), and a force sensor (65) is installed in axial contact with one end of the thrust bearing (64).

8. The electromechanical brake for automobile according to claim 6, characterized in that: At least two anti-rotation grooves (611) are arranged around the circumference on the end surface of the nut (61) connected to the dynamic friction plate (74), and an anti-rotation boss (741) embedded in the corresponding anti-rotation groove (611) is arranged on the outer wall of the dynamic friction plate (74).

9. The electromechanical brake for automobile according to claim 1, characterized in that: The shell (5) comprises a lower shell (53), an upper shell (52) and an upper cover (51) installed on the side of the upper shell (52); the upper shell (52) and the lower shell (53) are spliced ​​up and down, and the PCBA board (8) is installed in the space between the upper cover (51) and the upper shell (52).

10. A method for releasing parking control of an electronic mechanical brake for an automobile, characterized in that: When the brake drive motor (1) as described in any one of claims 1 to 9 receives a parking brake release signal, the brake drive motor (1) is first reversed. After the reversal, there is no torque between the ratchet (41) and the pawl (43). At this time, the locking motor (42) drives the pawl (43) to rotate and move it away from the ratchet (41), thereby releasing the parking lock device.

Images