Decoupling brake booster and vehicle

Abstract

The embodiment of the present application provides a decoupling type brake booster device and a vehicle. The decoupling type brake booster device comprises an input rod, a plunger, a booster motor and a control unit, an output push rod and a pedal feel simulation device, wherein the pedal feel simulation device comprises an axial guide rod, a support plate and a pedal feel simulation spring arranged on the axial guide rod and abutting against the support plate. The decoupling type brake booster device according to the embodiment can not only directly detect the brake pedal stroke and brake according to the detected pedal stroke, but also simulate the pedal feel close to the traditional brake system or vacuum booster.

Description

Technical Field

[0001] This invention relates to the field of vehicle brake assist, and more specifically, to a decoupled brake assist device and vehicle with pedal feel simulation function. Background Technology

[0002] To enable drivers to comfortably operate the braking system's components, such as the brake pedal, braking systems typically include a brake booster. Braking systems with a brake booster are often referred to as brake-assisted braking systems. For a vehicle, the brake booster assists the driver in establishing braking pressure when the driver presses the brake pedal.

[0003] Existing brake booster systems for passenger vehicles include two types: vacuum boosters and electronic boosters. Vacuum boosters are widely used in gasoline-powered passenger vehicles, while electronic boosters are widely used in new energy passenger vehicles. However, for new energy vehicles, especially electric vehicles, in order to achieve regenerative braking, it is desirable to utilize the drag effect of the vehicle's main motor (the motor itself reduces its speed) to participate in or achieve braking during the application of the brake pedal, rather than relying entirely on the friction pads of the vehicle's braking system. Simultaneously, the vehicle's main motor converts the vehicle's kinetic energy into electrical energy and feeds it back to the vehicle's energy storage system, thereby achieving energy recovery.

[0004] In existing braking systems, it is usually necessary to use a coupled brake booster and an ESPhev with an energy storage device to work together to achieve braking and kinetic energy recovery functions. This solution requires the coupled brake booster and ESPhev to work in perfect coordination during braking, which places high demands on the vehicle's braking matching and results in a high cost. Alternatively, a decoupled integrated braking device can be used alone to achieve braking and kinetic energy recovery functions, but the decoupled integrated braking device cannot meet the requirements of high-level autonomous driving.

[0005] The market expects a braking system solution that uses a decoupled brake booster and standard ESP to work together to achieve braking and kinetic energy recovery functions. The decoupled brake booster can simulate a pedal feel similar to that of a traditional braking system with a vacuum booster, so that drivers can adapt quickly. Summary of the Invention

[0006] The purpose of the embodiments of the present invention is to solve or at least alleviate the problems existing in the prior art.

[0007] According to some aspects, the purpose of embodiments of the present invention is to enable a decoupled brake booster to directly detect the brake pedal travel and perform braking based on the detected pedal travel, and to provide a technical solution for the decoupled brake booster device that is easy to manufacture on the production line and simplifies assembly.

[0008] The embodiments address the above problems by providing a pedal feel simulator assembly and a decoupled brake assist device.

[0009] Specifically, according to one aspect of the embodiments, a braking assist device is provided, comprising: An input lever for connecting to the brake pedal; When the brake pedal is pressed, the input rod drives the plunger connected to the input rod to move axially. A displacement sensor assembly that senses the axial displacement of the input rod or the plunger; A power assist motor and a control unit, wherein the control unit controls the power assist motor to operate in order to output braking assist torque; An output push rod is operably connected to the power assist motor to receive the braking assist torque and to perform axial displacement to output braking force to the brake cylinder; The brake assist device further includes: a pedal feel simulation device, the pedal feel simulation device comprising: An axial guide rod located radially outside the plunger; A support plate, the outer side of which is sleeved on the axial guide rod, wherein when the plunger contacts the middle of the support plate, the support plate moves together toward the brake master cylinder under the push of the plunger; and A pedal-feeling simulated spring is mounted on the axial guide rod, and the pedal-feeling simulated spring abuts against the support plate to apply a reaction force to the support plate.

[0010] On the other hand, a vehicle is also provided that includes a decoupled brake assist device according to various embodiments.

[0011] According to the embodiment, the decoupled brake booster can simulate a "pedal feel" similar to that of a conventional braking system with a vacuum booster. Attached Figure Description

[0012] Referring to the accompanying drawings, the disclosure of the embodiments will become more readily understood. It will be readily understood by those skilled in the art that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of the embodiments. Furthermore, similar numbers in the drawings are used to denote similar components, wherein: Figure 1 and Figure 2 A perspective view of a decoupled brake booster device according to an embodiment is shown, with and without a motor and control unit; Figure 3 , Figure 4 and Figure 5 It shows Figure 13D views of the decoupled brake booster unit from various angles, excluding the motor, control unit, and master cylinder. Figure 4 One connector has been removed to reveal the internal structure; Figure 6 A perspective view of some components of a decoupled brake booster device according to one embodiment is shown; Figure 7 It shows Figure 1 A longitudinal section view of a decoupled brake booster device; Figures 8 to 11 It shows Figure 1 Longitudinal cross-sectional views of the decoupled brake assist device during multiple stages of pedal depressing; Figure 12 It shows Figure 1 The theoretical pedal force versus pedal distance curve of a decoupled brake booster device; Figure 13 It shows Figure 1 A longitudinal cross-sectional view of an exemplary modification of the decoupled brake assist device; Figure 14 It shows Figure 1 A longitudinal cross-sectional view of another exemplary modification of the decoupled brake booster device; Figure 15 and Figure 16 Perspective views of a decoupled brake booster device according to another embodiment are shown from different angles; Figure 17 It shows Figure 15 A 3D view of the decoupled brake booster after removing the motor and control unit; Figure 18 It shows Figure 15 A longitudinal section view of a decoupled brake booster device; Figure 19 It shows Figure 15 An exemplary modification of a decoupled brake booster device; Figure 20 and Figure 21 Perspective views of a decoupled brake booster device according to another embodiment, with and without a motor and control unit, are shown; and Figure 22 It shows Figure 20 and Figure 21 A longitudinal section view of the decoupled brake assist device in the image. Detailed Implementation

[0013] It is readily understood that, based on the technical solutions of the embodiments, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the embodiments. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative descriptions of the technical solutions of the embodiments and should not be considered as all of the embodiments or as limitations or restrictions on the technical solutions of the embodiments.

[0014] The directional terms such as up, down, left, right, front, back, front, back, top, and bottom mentioned or possibly used in this specification are defined relative to the structures shown in the accompanying drawings. These are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive. Furthermore, the terms "first," "second," "third," and similar expressions are used for descriptive and distinguishing purposes only and should not be construed as indicating or implying the relative importance of the corresponding components.

[0015] refer to Figures 1 to 7This paper introduces a decoupled braking assist device according to one embodiment. The decoupled brake assist device includes: an assist motor and its control unit 28, which provides the initial torque for generating brake assist and controls the operation of the assist motor based on various information; a gear transmission assembly consisting of two or more gears, which amplifies the motor torque and transmits it to the main shaft nut 24. For example, in the illustrated embodiment, a gear on the output shaft of the assist motor meshes with a double gear 29, which further meshes with a central gear 241 on the main shaft nut 24. The central gear 241 can be splined to engage with the main shaft nut 24, thereby amplifying the torque of the assist motor and transmitting it to the main shaft nut 24; a main housing 100, which supports and covers various components inside the assist motor; a main shaft nut 24 and a main shaft 21, which are coaxially arranged, with the inner ring of the main shaft nut 24 and the outer ring of the main shaft 21 having matching threads. The inner end of the main shaft 21 is fixedly connected to an anti-rotation plate 91, and the outer ring of the anti-rotation plate 91 is further fitted, for example, by a bushing 95. A pair of through rods 9 mounted on the main housing 100 prevent the anti-rotation plate 91 and the main shaft 21 from rotating, thereby converting the torque transmitted from the power assist motor via the main shaft nut 24 into the axial movement of the main shaft 21. One end of each through rod 9 is connected to and secures the brake master cylinder 50, and the other end is connected to the main housing 100. The middle section is used to assemble with the anti-rotation plate 91 to guide its axial movement and prevent it from rotating. A support member 25 is connected at one end to the return spring retainer 59 on the back side of the output push rod 5. The other end is connected to the anti-rotation plate 91, which is used to transmit the thrust of the main shaft 21 to the output push rod 5; the output push rod 5 is used to output the thrust to the brake master cylinder 50 of the decoupled brake booster; the return spring 58 acts on the return spring retainer 59 supporting the back side 51 of the output push rod 5, which is used to keep the main shaft, anti-rotation plate, output push rod, and gear transmission assembly in the initial position, or to push the main shaft, anti-rotation plate, pedal feel simulator, output push rod, and gear transmission assembly back to the initial position after braking.

[0016] Additionally, the brake assist device further includes: an input rod 1, comprising an outer end 11 and an inner end 12, the outer end 11 being connected to the brake pedal to receive and transmit the brake pedal force applied by the driver; a plunger 2 connected to the inner end 12 of the input rod 1, the plunger 2 being located inside the hollow main shaft 21 and capable of axial movement relative to the main shaft 21, the input rod 1 driving the plunger 2 to move axially when the brake pedal is depressed; and a displacement sensor assembly, which includes, for example, a magnet 94 connected to the plunger 2 via a bracket 93 and a fixed magnet sensor assembly 99, the magnet sensor assembly 99 sensing the axial displacement of the magnet 94 and the plunger 2 by sensing the change in magnetic field caused by the movement of the magnet 94, thereby sensing the travel of the brake pedal and feeding it back to the control unit. In an alternative embodiment, the displacement sensor assembly may be connected to the input rod 1 to detect the axial displacement of the input rod 1, thereby sensing the travel of the brake pedal. In an alternative embodiment, the displacement sensor assembly may detect the travel of the brake pedal based on other methods, such as a light sensor. The decoupled brake assist device according to the embodiment further includes: a pedal feel simulation device, which includes: an axial guide rod 7 located radially outside the plunger 2, for example, a pair of axial guide rods 7, a support plate 6, the outer side 62 of the support plate being sleeved on the axial guide rod 7. Figure 7 In this embodiment, in the initial state, the plunger 2 is spaced apart from the support plate 6. As the plunger 2 moves, the plunger 2 will contact the support plate 6, and the support plate 6 will move together towards the brake master cylinder 50 under the push of the plunger 2. Pedal-feel simulation springs 82 and 83 are mounted on the axial guide rod 7. These springs are fitted onto the axial guide rod 7, and their initial resistance acts on the support plate 6, causing it to abut against the boss portion 79 located in the middle of the axial guide rod. During the movement of the pedal, the pedal-feel simulation springs 82 and 83 are compressed by the support plate 6 to provide a reaction force to the support plate 6. The force, i.e., the pedal feel feedback force; the starting spring 23, fitted on the input rod 1, with its left end abutting against the main shaft 21 and its right end abutting against the retaining ring on the input rod 1, is used to provide the first stage of pedal feel, i.e., the initial pedal feel before the end of the plunger 2 contacts the support plate 6; the disc spring assembly 87, which consists of two or more disc springs and is connected to the inner end 26 of the plunger 2, is shown in the illustrated embodiment as two concentric disc springs. This disc spring assembly 87 contacts the support plate 6 and is compressed when the plunger 2 moves, thereby providing the second stage of pedal feel. In addition, as will be described in detail below, the pedal feel simulation springs 82 and 83 provide the third stage of pedal feel.

[0017] In this embodiment, the outer ring of the plunger 2 is provided with a main shaft 21, and the outer ring of the main shaft 21 is provided with a main shaft nut 24. The main shaft 21 and the main shaft nut 24 are threadedly engaged. In this embodiment, the anti-rotation plate 91 has a through hole at its center, which is fitted into the inner end of the main shaft 21 and fixedly connected to the main shaft 21. Alternatively, the anti-rotation plate 91 can be connected to the main shaft in other ways. Sliding sleeves can be installed at both ends of the anti-rotation plate 91, and the sliding sleeves are respectively fitted onto the through rod 9, thereby restricting the rotation of the anti-rotation plate 91 and the main shaft 21. A hollow gear 241 is fitted on the outer side of the main shaft nut 24. The hollow gear 241 is splinedly connected to the main shaft nut 24, and the power motor drives the hollow gear 241 via a reduction gear set. Since the main shaft 21 and the main shaft nut 24 are threadedly engaged, and the rotational movement of the main shaft 21 is restricted and cannot rotate, the rotation of the main shaft nut 24 will cause the main shaft 21 to move axially. Figure 5 and Figure 6 As clearly shown, the support member 25 is symmetrically arranged on both sides of the plunger 2 and is located on the side of the anti-rotation plate 91 near the brake master cylinder. One end of the support member 25 is fixedly connected to the anti-rotation plate 91, and the other end is fixedly connected to the return spring retainer 59 on the back side of the output push rod 5. It has no connection with the plunger 2 and can move independently along the axial direction. Therefore, driven by the power assist motor, the axial movement of the main shaft 21 will drive the anti-rotation plate 91, the support member 25 and the output push rod 5 to move to the left together. Finally, the output push rod 5 transmits the thrust to the brake master cylinder 50, thereby driving the brake master cylinder 50 to establish braking pressure.

[0018] from Figures 3 to 7 As can be seen from the diagram, the decoupled brake booster according to the embodiment employs two support members 25, and the two support members 25 and the anti-rotation plate 91 form a through groove with openings on three sides. The middle part 61 of the support plate 6 is located in this through groove, and the support plate 6 can translate axially within the through groove. The disc spring assembly 87 and the magnet bracket 93 are fixedly connected to the plunger 2. The disc spring assembly 87 and the magnet bracket 93 extend from the through groove between the two support members 25, and the disc spring assembly 87 can translate axially within the through groove, but its rotational movement along the axis is restricted. The anti-rotation plate 91 has through holes symmetrical about the axis of the main shaft 21 on both sides. The through holes of the anti-rotation plate 91 respectively cooperate with the bosses at both ends of the magnet bracket, thereby avoiding the influence of the anti-rotation plate 91 on the magnet bracket 93 when it moves.

[0019] It can be seen that the axial movements of the motor-driven spindle 21, anti-rotation plate 91, and support member 25 are staggered from and do not interfere with each other in the central space, along with the axial movements of the input rod 1, plunger 2, disc spring assembly 87, magnet bracket 93, and support plate 6.

[0020] In the embodiment, reference Figure 7The axial guide rod 7 has a retaining ring 71 spaced apart from the support plate 6. A spacer 72 is provided between the retaining ring 71 and the support plate 6. A second pedal-feel simulation spring 83 is provided between the spacer 72 and the support plate 6, and a first pedal-feel simulation spring 82 is provided between the spacer 72 and the retaining ring 71. In an alternative embodiment, only one pedal-feel simulation spring 82 may be provided between the support plate 6 and the retaining ring 71.

[0021] Unlike existing brake assist devices for passenger cars (where the input rod 1 and the output push rod 5 are connected and move together), the decoupled brake assist device according to the embodiment can be configured into two working modes, decoupled and coupled, depending on the contact state between the input rod 1 and the output push rod 5, and can be applied to different braking states of different types of vehicles. When the decoupled brake assist device according to the embodiment is applied to new energy vehicles, especially electric vehicles, and the driver depresses the brake pedal to brake, the control unit can determine whether the brake assist module should work based on the current vehicle speed and the detected displacement signal of the plunger 2 (i.e., pedal travel). If the pedal travel is less than a threshold (or decoupling distance) and the drag torque of the vehicle's main motor at the current vehicle speed can meet the braking requirements, the brake assist module will not work, that is, the brake assist motor 28 will not work, and the output push rod 5 will not move with the axial displacement of the plunger 2, i.e., the pedal travel will not be affected. Displacement will not cause the output push rod 5 to output braking force. If the pedal travel is less than a threshold (or decoupling distance) and the drag torque of the vehicle's main motor at the current vehicle speed cannot meet the braking requirements, the brake assist module will quickly respond to the displacement signal of the plunger 2 and start working. That is, the brake assist motor starts to output torque. Driven by the motor, the output push rod 5 will move with the axial displacement of the plunger 2, thereby pushing the brake master cylinder 50 to build pressure. At this time, the brake assist module works in coordination with the drag torque of the vehicle's main motor according to the detected displacement signal of the plunger 2 to jointly achieve braking. In the above process, although the input rod 1 and the plunger 2 are displaced, they never contact the output push rod 5. This process is the decoupling working mode of the decoupled brake assist device. The stroke of the input rod 1, i.e. the decoupling stroke, can be set to, for example, 5mm-18mm, which corresponds to the stroke of the disc spring assembly 87 before it contacts the support plate 6 and reaches maximum deformation. If the pedal travel is greater than or equal to the aforementioned threshold, i.e., after the decoupling travel, the decoupled brake assist device enters the coupling mode. In the coupling mode, the vehicle's main motor does not participate in braking. The control unit controls the operation of the brake assist module based on the current vehicle speed and the detected displacement of the plunger 2. Driven by the motor, the output push rod 5 moves with the axial displacement of the plunger 2, thereby pushing the brake master cylinder 50 to build up pressure, ultimately achieving vehicle braking. Therefore, during the coupling travel, the braking force is mainly provided by the brake master cylinder 50.

[0022] When the brake assist device according to the embodiment is applied to an internal combustion locomotive, and the driver presses the brake pedal to brake, the brake assist module quickly responds to the displacement signal of the plunger 2 and starts to work, that is, the brake assist motor starts to output torque. Under the drive of the motor, the output push rod 5 will move with the axial displacement of the plunger 2, thereby pushing the brake master cylinder to build up pressure. At this time, the brake assist module outputs the corresponding braking force according to the detected displacement signal of the plunger 2, thereby meeting the driver's braking needs.

[0023] In this type of decoupled brake assist device, since there is no actual mechanical coupling between the input rod 1, the plunger 2 and the output push rod 5 during the decoupling stroke, the driver will not feel the reaction force of the braking system when pressing the brake pedal, and therefore will not feel the pedal feel that is familiar or adapted to when braking. Therefore, it is expected that the decoupled brake assist device according to the embodiment can simulate the pedal feel of a conventional brake assist system.

[0024] Therefore, the decoupled brake assist device according to the embodiment further includes: a pedal feel simulation device, which includes: an axial guide rod 7 located radially outside the plunger 2, the axial guide rod 7 being attachable to the gear housing 100; a support plate 6, the outer side 62 of the support plate 6 being sleeved on the axial guide rod 7, for example, a bushing fixed to the support plate 6 being sleeved on the guide rod 7, when the plunger contacts the inner side 61 of the support plate, the support plate 6 moves together toward the brake master cylinder 50 under the push of the plunger; a retaining ring 71, the axial guide rod 7 having a retaining ring 71 spaced apart from the support plate 6, a spacer 72 between the retaining ring 71 and the support plate 6, a first pedal feel simulation spring 82 being provided between the spacer 72 and the retaining ring 71, and a second pedal feel simulation spring 83 being provided between the spacer 72 and the support plate 6, the initial resistance provided by the pedal feel simulation springs 82 and 83 acting on the support plate 6, causing it to abut against the boss portion 79 constructed in the middle of the axial guide rod. The pedal feel simulation springs 82 and 83 are compressed by the support plate 6 during the movement of the brake pedal, providing a reaction force to the support plate 6, i.e., the pedal feel feedback force. The second pedal feel simulation spring 83 and the spacer 72 are optional components; their inclusion can be selected based on actual needs. The starting power spring 23, fitted onto the input rod, abuts against the main shaft 21 at its left end and against the retaining ring on the input rod 1 at its right end. The starting power spring 23, after compression, provides a reaction force to achieve the first stage of pedal feel, i.e., the initial pedal feel. The disc spring assembly 87, composed of two or more disc springs, also participates in achieving the pedal feel.

[0025] Continue to refer to Figures 8 to 11Let's describe the specific pedal feel simulation process. When the driver presses the brake pedal, and the thrust generated by the brake pedal exceeds the initial resistance of the starting spring 23, it begins to push the input rod 1 and plunger 2 towards the brake master cylinder 50. Simultaneously, the starting spring 23 begins to compress, thus generating the first stage of pedal feel, corresponding to... Figure 12 The A section of the pedal feel curve and Figures 7 to 8 The process involves continuing to depress the brake pedal, with input lever 1 and plunger 2 moving towards the master cylinder 50. When one of the disc springs in the disc spring assembly 87 begins to contact the support plate 6, the second stage of pedal feel begins. Continuing to depress the brake pedal, input lever 1 and plunger 2 move towards the master cylinder 50, and the disc springs in the disc spring assembly 87 deform sequentially. This process forms the second stage of pedal feel, which corresponds to... Figure 12 Section B and Figures 8 to 9 The process, such as Figure 12 As shown, the second pedal feel curve B has two segments, corresponding to the case of two disc springs. Selecting other numbers of disc springs can change the pedal feel curve of this segment. Continuing to depress the brake pedal, input rod 1 and plunger 2 continue to move towards the master cylinder 50. When plunger 2 abuts against support plate 6, the disc spring assembly 87 reaches its maximum deformation, at which point the second pedal feel ends and the third pedal feel begins. Continuing to depress the brake pedal, input rod 1 and plunger 2 push support plate 6 towards the master cylinder. Support plate 6 begins to compress the pedal feel simulation springs 82 and 83. This process forms the third pedal feel and an optional fourth pedal feel, corresponding to... Figure 12 Sections C and D in the middle and Figures 9 to 11 In the process, the first pedal-sensing springs 82 and 83 are first compressed together until... Figure 10 In section C, after the spacer 72 abuts against the support plate 6, only the first pedal feel simulation spring 82 is compressed (section D). Continuing to depress the brake pedal, the input lever 1 and plunger 2 push the support plate 6 towards the brake master cylinder 50. When the pedal travel exceeds, for example, 20mm, the support plate 6 begins to abut against the return spring retainer 59. At this point, the third pedal feel ends. Subsequent pedal feel is mainly formed by the deformation of the pedal feel simulator and other components of the vehicle's braking system.

[0026] During the operation of the pedal simulator, the starting power spring 23, disc spring assembly 87, pedal feel simulation springs 82 and 83 will generate reaction forces when they deform. The resultant force of all reaction forces will be transmitted to the brake pedal through the plunger 2 and input rod 1. This force is equal in magnitude and opposite in direction to the input force acting on the input rod 1 when the driver presses the brake pedal. The resultant force of the reaction forces will be fed back to the driver through the brake pedal and perceived by the driver. Combined with the displacement of the brake pedal at this time, it will form the pedal feel that the driver is already familiar with or adapted to when braking.

[0027] Continue to refer to Figures 7 to 12 The decoupled brake assist device according to this embodiment will be described in detail. In this embodiment, the inner end 26 of the plunger 2 is connected to the disc spring assembly 87. For example, in the illustrated embodiment, two disc springs are included, which are arranged in parallel and have different radii of curvature. The two disc springs 87 are spaced apart from the support plate 6, with a certain gap between them, which can be used as the decoupling distance. Different decoupling distances can be set according to different vehicle models or overall vehicle requirements, for example, 5-18mm. In addition, in this embodiment, a starting power spring 23 is provided between the main shaft 21 and the input rod 1. When the brake pedal is initially pressed, as... Figures 7 to 8 During the process, input rod 1 pushes plunger 2 to move axially, and the starting spring 23 is compressed to provide a reaction force, which corresponds to Figure 12 Section A of the diagram. As detailed above, when used in electric vehicles, during this process (i.e., when the pedal travel is less than the decoupling distance), the control unit can determine whether the brake assist module should operate based on the current vehicle speed and the detected displacement signal of plunger 2. If the drag torque of the vehicle's main motor can meet the braking requirements at the current vehicle speed, the brake assist module will not operate, meaning the brake assist motor will not operate, and the output push rod 5 will not move with the axial displacement of plunger 2; that is, the pedal displacement will not cause the output push rod 5 to output braking force. If the drag torque of the vehicle's main motor cannot meet the braking requirements at the current vehicle speed, the brake assist module will quickly respond to the displacement signal of plunger 2 and start operating; that is, the brake assist motor will start outputting torque, and under the drive of the motor, the output push rod 5 will move with the axial displacement of plunger 2, thereby pushing the brake master cylinder 50 to build pressure. At this time, the brake assist module works in coordination with the drag torque of the vehicle's main motor based on the detected displacement signal of plunger 2 to jointly achieve braking. Figure 8 In the embodiment shown, the assist motor is not working, the main shaft 21 is not moving, and the output push rod 5 is not moving. Therefore, the brake assist device only records and outputs the displacement information of the plunger 2 or the input rod 1. At this time, the whole vehicle relies on the drag torque of the main motor to brake, and the kinetic energy of the whole vehicle is converted into electrical energy and fed back to the energy storage device through a specific device, thereby realizing energy recovery.

[0028] Continue to refer to Figure 8 and Figure 9 ,exist Figure 8 If the brake pedal is pressed continuously under these conditions, each disc spring in the disc spring assembly 87 will deform sequentially until... Figure 9 In the state shown, the disc spring assembly 87 reaches its maximum deformation. During this process, the reaction force generated by the combined deformation of the starting spring 23 and the disc spring assembly 87 is transmitted to the brake pedal through the plunger 2 and the input rod 1. Combined with the displacement of the input rod 1 at this time, the second stage of pedal feel is formed, which corresponds to... Figure 12 Section B in the system can be configured with different travel ranges for different vehicle models or overall vehicle requirements, such as approximately 7-12mm. The disc spring assembly 87 can be composed of one or more disc springs stacked sequentially. The sequential deformation of multiple disc springs (e.g., two, three, or four) can make the pedal feel corresponding to that travel range smoother and closer to the desired pedal feel curve. During this process, the operating logic of the control unit and its... Figures 7 to 8 The working logic remains consistent throughout the process. It determines whether the brake assist module should operate based on the current vehicle speed and the detected displacement signal of plunger 2. If the drag torque of the vehicle's main motor is sufficient to meet braking requirements at the current vehicle speed, the brake assist module will not operate; that is, the brake assist motor 28 will not operate, and the output push rod 5 will not move with the axial displacement of plunger 2. In other words, the pedal displacement will not cause the output push rod 5 to output braking force. If the drag torque of the vehicle's main motor is insufficient to meet braking requirements at the current vehicle speed, the brake assist module will quickly respond to the displacement signal of plunger 2 and begin operating. The brake assist motor will start outputting torque, and under the motor's drive, the output push rod 5 will move with the axial displacement of plunger 2, thereby pushing the master cylinder to build pressure. At this time, the brake assist module, based on the detected displacement signal of plunger 2, works in conjunction with the drag torque of the vehicle's main motor to achieve braking. Figure 9The embodiment shown is an example of a power-assisted motor that drives the output push rod 5 to move. During this process, the control unit controls the brake assist module to quickly respond to the displacement signal of the plunger 2 and start working based on the current vehicle speed and the displacement signal of the plunger 2. Driven by the control unit, the power-assisted motor starts to generate torque. This torque is amplified by the gear transmission mechanism and transmitted to the main shaft nut 24. The main shaft 21 and the main shaft nut 24 are connected by threads, so the torque is then transmitted to the main shaft 21 through the main shaft nut 24. Since the main shaft 21 is fixedly connected to the anti-rotation plate 91, the rotational movement of the main shaft 21 is constrained. Therefore, under the combined action of torque and threads, the main shaft 21 and the anti-rotation plate 91 move together along the axis towards the brake master cylinder, thereby pushing the support 25, the return spring retainer 59 and the output push rod 5 to move together along the axis towards the brake master cylinder 50, thereby pushing the brake master cylinder to build up pressure. The anti-rotation plate 91 is fixed at both ends to a pair of through rods 9 by sliding sleeves, preventing it from rotating. Therefore, when the main shaft 21 moves to the left, the anti-rotation plate 91 also moves to the left along the anti-through rods 9. During this process, the support plate 6 and the return spring retainer 59 maintain a distance, meaning they do not contact each other.

[0029] Continue to refer to Figure 9 , Figure 10 and Figure 11 ,exist Figure 9 Further pressing the brake pedal will cause the plunger 2 to push the support plate 6 to move along the axial guide rod 7, thereby compressing the first pedal-sensing simulated spring 82 and the second pedal-sensing simulated spring 83 on the axial guide rod 7. In the illustrated embodiment, the spacer 72 is U-shaped and has a flat portion 721, which engages with the support plate 6 after the first pedal-sensing simulated spring 82 is compressed. The first pedal-sensing simulated spring 82 may have a greater rigidity than the second pedal-sensing simulated spring 83. Figure 10 As shown, the first pedal feel simulation spring 82 and the second pedal feel simulation spring 83 are compressed together because they are connected in series. (Reference) Figure 11 The second pedal feel simulation spring 83 is compressed until the flat portion 721 of the spacer 72 engages with the support plate 6. In the subsequent stroke, the second pedal feel simulation spring 83 will not be compressed again. During this process, the reaction force generated by the combined deformation of the starting spring 23, the disc spring assembly 87, the first pedal feel simulation spring 82, and the second pedal feel simulation spring 83 is transmitted to the brake pedal through the plunger 2 and the input rod 1. Combined with the displacement of the input rod 1 at this time, a third segment of pedal feel is formed, which corresponds to... Figure 12The C section of the curve can be set with different strokes depending on the vehicle model or overall vehicle requirements, for example, approximately 5-18mm. During this stroke, a significant deceleration is typically required to reduce the vehicle speed to a safe level within a short time. To ensure driving safety, the drag torque of the vehicle's main motor is no longer used for braking; instead, the brake assist module is used entirely. During this process, the control unit, based on the current vehicle speed and the displacement signal of plunger 2, controls the brake assist module to quickly respond to the displacement signal of plunger 2 and begin operation. Driven by the control unit, the assist motor operates and pushes the output push rod 5 along the axis toward the brake master cylinder 50 in the same manner as previously described, thereby building pressure in the brake master cylinder and achieving braking.

[0030] Finally, refer to Figure 10 and Figure 11 ,exist Figure 10 Continuing to press the brake pedal will cause the first pedal feel simulation spring 82 to be further compressed. During this process, the reaction force generated by the combined deformation of the starting spring 23, disc spring assembly 87, first pedal feel simulation spring 82, and second pedal feel simulation spring 83 is transmitted to the brake pedal through the plunger 2 and input rod 1. Combined with the displacement of the input rod 1 at this time, a fourth pedal feel is formed, and this pedal travel corresponds to... Figure 12 The D section of the curve can be set with different strokes depending on the vehicle model or overall vehicle requirements, for example, about 3mm. Since the stiffness coefficient of the first pedal feel simulation spring 82 is greater than that of the second pedal feel simulation spring 83, the slope of section D is greater than that of section C. In this stroke, a large deceleration is usually required to reduce the vehicle speed to within a safe speed range in a short time. To ensure driving safety, the drag torque of the vehicle's main motor can no longer be used for braking during this process. Instead, the braking assist module is used entirely for braking. During this process, the control unit controls the braking assist module to quickly respond to the displacement signal of the plunger 2 and start working based on the current vehicle speed and the displacement signal of the plunger 2. Driven by the control unit, the assist motor will work and push the output push rod 5 to move along the axis toward the brake master cylinder in the same way as previously described, thereby pushing the brake master cylinder to build pressure and thus achieving braking.

[0031] Finally, when the brake pedal is released, each spring in the pedal simulator module returns to its initial state by its own elasticity, and also pushes each component back to its initial state; at the same time, under the elasticity of the return spring 58, each component of the brake booster module is also pushed back to its initial state.

[0032] Therefore, through Figures 1 to 11 The decoupled brake booster device of the embodiment shown can achieve, for example Figure 12 The feedback curves of theoretical pedal travel and pedal force shown are the pedal feel curves.

[0033] On the other hand, in the event of power failure, assist motor failure, or other assist failures, when the brake pedal is pressed, the assist motor will not drive the output push rod 5 to move. In this case, the input rod 1 and plunger 2 overcome the elastic force of the starting spring 23 and disc spring assembly 87 and abut against the support plate 6. This pushes the support plate 6 to directly engage with the return spring retainer 59 on the back side of the output push rod 5. After overcoming the elastic force of the pedal feel simulation spring 82 and pedal feel simulation spring 83, the output push rod 5 is directly pushed along the axis towards the brake master cylinder, thereby pushing the brake master cylinder to build pressure and achieving braking. This arrangement prevents braking from being achieved by the driver pressing the brake pedal even in the event of brake assist failure, such as a power outage or malfunction of the assist motor.

[0034] Continue to refer to Figure 13 A modification according to an embodiment of the present invention will now be introduced. In this modification, one of the disc springs 871 in the disc spring assembly 87 contacts the support plate 6 in its initial state, thereby providing the first pedal feel by means of the disc spring 871 replacing the starting spring 23. Continuing to refer to Figure 14 A modification according to an embodiment of the present invention will be introduced. In this modification, a helical spring 88 located between the support plate 6 and the plunger 2 is used instead of the disc spring assembly 87 and the starting spring 23, thereby providing both the first and second pedal feel by the helical spring 88.

[0035] Continue to refer to Figure 15 and Figure 18 To illustrate another embodiment of the decoupled brake assist device according to the embodiments. Figure 15 The displacement sensor assembly 99 is shown, located radially outward of the plunger 2. Figure 18As can be seen more clearly in this embodiment, the disc spring assembly 87 is omitted, and the spring 81 between the retaining ring 71 on the axial guide rod 7 and the support plate 6 is used as the starting power spring. The starting power spring 81 is respectively fitted on the outside of the pedal feel simulation spring 82 and the pedal feel simulation spring 83. The inner end of the plunger 2 is directly fixedly connected to the magnet bracket, and the magnet bracket abuts against the support plate 6 on the side near the brake master cylinder. In addition, in this embodiment, the axial guide rod 7 has a retaining ring 71 that is separated from the support plate 6. The starting power spring 81 is constructed between the retaining ring 71 and the support plate 6. The first pedal feel simulation spring 82 and the second pedal feel simulation spring 83 are arranged radially inside the starting power spring 81. The first end (left end) of the first pedal feel simulation spring 82 is connected to the retaining ring 71, and the second end (right end) of the first pedal feel simulation spring 82 is connected to the first bushing 74. The first end of the second pedal feel simulation spring 83 is connected to the first bushing 74, and the second end (right end) of the second pedal feel simulation spring 83 is connected to the second bushing 75. When the brake pedal is not depressed, the support plate 6, the second bushing 75, the first bushing 74, and the retaining ring 71 are all spaced apart. In this structure, there is a gap between the support plate 6 and the back side 51 of the output push rod 5. When the brake pedal is depressed, the starting force spring 81 is first compressed until the support plate 6 contacts the second bushing 75, then the first pedal feel simulation spring 82 and the second pedal feel simulation spring 83 are compressed until the second bushing 75 engages with the first bushing 74, and finally the second pedal feel simulation spring 83 is no longer compressed while the first pedal feel simulation spring 82 is compressed. This structure can also provide... Figure 12 The theoretical pedal travel and pedal force feedback curve shown are known as the pedal feel curves, which include three segments corresponding to the initial force spring 81, the second pedal feel simulation spring 83, and the first pedal feel simulation spring 82. According to this embodiment, the decoupled brake assist device has the same brake assist module as the brake assist module of the first embodiment, and its operating mode and operating logic at each stage are also the same as those of the brake assist module of the first embodiment.

[0036] Continue to refer to Figure 19 A modification of the brake assist device according to the present invention is introduced. The first pedal feel simulation spring 82 and the second pedal feel simulation spring 83 are replaced by a plurality of disc springs 891 connected in series. The first end of the plurality of disc springs 891 is connected to a retaining ring 71, and the second end is connected to a movable retaining ring 76. After the bushing of the support plate contacts the movable retaining ring 76, the plurality of disc springs 891 connected in series are compressed in order to simulate various pedal feel curves.

[0037] See again Figure 20 and Figure 22To illustrate another embodiment of the decoupled brake booster device according to the embodiments, we will now introduce a different type of brake booster device. In this embodiment, unlike the previous embodiments where the support plate 6 and pedal feel simulation springs 81, 82, and 83 are respectively sleeved on an axial guide rod 7 that is parallel to the through rod 9 and circumferentially offset, in this embodiment, the support plate 6 and the pedal feel simulation springs 81, 82, and 83 are respectively sleeved on the axial guide rod 7. That is, the support plate 6 and the anti-rotation disc 9 share the axial guide rod 7. The support plate 6 is located between the anti-rotation plate 91 and the brake master cylinder, and the support member 25 is located between the anti-rotation plate 91 and the support plate 6. This structure can also provide the same... Figure 12 The theoretical pedal travel and pedal force feedback curve shown are known as the pedal feel curves, which include three segments corresponding to the initial force spring 81, the second pedal feel simulation spring 83, and the first pedal feel simulation spring 82. According to this embodiment, the decoupled brake assist device has the same brake assist module as the brake assist module of the first embodiment, and its operating mode and operating logic at each stage are also the same as those of the brake assist module of the first embodiment. According to another aspect of the embodiments, a new energy vehicle, particularly an electric vehicle, is also provided, which includes a brake assist device according to various embodiments. In the new energy vehicle, particularly the electric vehicle, during the decoupling stroke of the brake assist device, the control unit determines whether the brake assist module should operate based on the current vehicle speed and the detected displacement signal of the brake pedal. If the drag torque of the vehicle's main motor can meet the braking requirements at the current vehicle speed, the brake assist module does not operate, that is, the brake assist motor will not operate, and the output push rod will not move with the axial displacement of the brake pedal, that is, the displacement of the pedal will not cause the output push rod to output braking force. If the drag torque of the vehicle's main motor cannot meet the braking requirements at the current vehicle speed, the brake assist module quickly responds to the displacement signal of the brake pedal and starts to operate, that is, the brake assist motor starts to output torque. Driven by the output push rod, the brake pedal moves axially, pushing the master cylinder to build up pressure. At this time, the brake assist module works in conjunction with the drag torque of the vehicle's main motor based on the detected brake pedal displacement signal to achieve braking. When the drag torque of the vehicle's main motor participates in braking, the kinetic energy of the vehicle can be converted into electrical energy and fed back to the energy storage device through a specific device, thereby realizing energy recovery. In coupled operation mode or when the set vehicle energy recovery conditions are exceeded, the vehicle's main motor does not participate in braking. The control unit controls the operation of the brake assist module based on the current vehicle speed and the detected brake pedal displacement. Driven by the motor, the output push rod moves axially with the brake pedal, pushing the master cylinder to build up pressure, ultimately achieving vehicle braking. During this process, since the vehicle's main motor does not participate in braking, there is no energy recovery. It should be understood that the decoupled brake booster of this embodiment can be installed on various vehicles, including gasoline vehicles, diesel vehicles, cars, trucks, buses, hybrid vehicles, pure electric vehicles, etc. In particular, this decoupled brake booster can be used in new energy vehicles with a main motor. Furthermore, when applied to internal combustion engine vehicles, this decoupled brake booster can operate as an electronically controlled device. That is, upon detecting the driver's intention to brake, it sends a braking signal to the vehicle's braking system like a controller, thereby achieving braking in real time.

[0038] It should be noted that the so-called decoupled type means that when the input rod of the pedal feel simulator moves towards the brake master cylinder, the support plate and the output push rod can be coupled and decoupled, that is, they can be in contact and non-contact. In the non-contact case, the entire brake booster brakes in one way, for example, it can rely solely on the drag torque of the vehicle's main motor to achieve braking, or the hydraulic brake master cylinder can work in conjunction with the drag torque of the vehicle's main motor to achieve braking. In the contact case, the entire brake booster brakes in another way, for example, the hydraulic brake master cylinder can work in conjunction with the drag torque of the vehicle's main motor to achieve braking, or there can be no drag torque from the main motor, and braking can be achieved solely by the hydraulic master brake cylinder in conjunction with the brake booster. Since the focus of this article is on the design of the pedal travel sensor module, the elastomer, the overall dimensions of the booster, and the main shaft nut bearing, other components of the decoupled brake booster, including its working principle, will not be described in detail.

[0039] It should be understood that the dimensions, shape, stiffness coefficient, spring pitch, wire diameter, steel plate thickness, inner diameter, material, and arrangement (such as series or parallel) of the starting spring, pedal feel simulation spring, and disc spring assembly can all affect the characteristic curve of the entire pedal feel simulation mechanism. The desired parameters and characteristic curves can be obtained through experience, experiments, and user feedback.

[0040] The specific embodiments described above are merely for the purpose of more clearly illustrating the principles of the embodiments, wherein various components are clearly shown or described to make the principles of the embodiments easier to understand. Various modifications or variations can be easily made to the embodiments by those skilled in the art without departing from the scope of the embodiments. Therefore, it should be understood that these modifications or variations should be included within the patent protection scope of the embodiments.

Claims

1. A decoupled brake assist device, comprising: Input lever (1), the input lever (1) is used to connect to the brake pedal; When the brake pedal is pressed, the plunger (2) connected to the input rod (1) causes the input rod (1) to move the plunger (2) axially. A displacement sensor assembly that senses the axial displacement of the input rod (1) or the plunger (2); A power assist motor and a control unit (28), wherein the control unit controls the power assist motor to operate in order to output braking assist torque; Output push rod (5), which is operably connected to the power assist motor to receive the braking assist torque and perform axial displacement to output braking force to the brake cylinder (50); The braking assist device is characterized in that it further includes: a pedal feel simulation device, the pedal feel simulation device comprising: Axial guide rod (7) located radially outside the plunger (2); A support plate (6), the outer side (62) of which is sleeved on the axial guide rod (7), when the plunger (2) contacts the middle part (61) of the support plate (6), the support plate (6) moves together towards the brake master cylinder under the push of the plunger (2); and A pedal-feeling simulated spring is provided on the axial guide rod (7), and the pedal-feeling simulated spring abuts against the support plate (6) to apply a reaction force to the support plate (6); The plunger (2) has a main shaft (21) on its outer ring, and a main shaft nut (24) on its outer ring. The main shaft (21) and the main shaft nut (24) are threaded together. The inner end of the main shaft (21) is fixedly connected to the middle of the anti-rotation plate (91). The outer side of the anti-rotation plate (91) is sleeved on the through rod (9) or the axial guide rod (7), thereby restricting the rotation of the anti-rotation plate (91) and the main shaft (21). The power assist motor drives the main shaft (21) via a reduction gear set. The spindle nut (24) rotates, and the spindle nut (24) drives the spindle (21) to move axially toward the brake master cylinder by means of the threaded engagement with the spindle (21). The support member (25) is arranged on the side of the anti-rotation plate (91) near the brake master cylinder, and the first end of the support member (25) is fixedly connected to the anti-rotation plate (91), the second end of the support member (25) is fixedly connected to the return spring retainer (59), and the return spring retainer (59) supports the output push rod (5).

2. The decoupled braking assist device according to claim 1, characterized in that, In the initial state where the brake pedal is not pressed, the plunger (2) is spaced apart from the support plate (6), and a disc spring assembly (87) is provided at the end (26) of the plunger (2).

3. The decoupled braking assist device according to claim 2, characterized in that, One of the disc springs (871) in the disc spring assembly (87) contacts the support plate (6).

4. The decoupled braking assist device according to claim 1, characterized in that, In the initial state where the brake pedal is not pressed, the plunger (2) is spaced apart from the support plate (6), and a helical spring (88) is provided between the end (26) of the plunger (2) and the support plate (6).

5. The decoupled braking assist device according to claim 1, 2, or 4, characterized in that, The axial guide rod (7) has a retaining ring (71) spaced apart from the support plate (6). A spacer (72) is sleeved on the axial guide rod (7) between the retaining ring (71) and the support plate (6). A first pedal feel simulation spring (82) is provided between the spacer (72) and the retaining ring (71). A second pedal feel simulation spring (83) is provided between the spacer (72) and the support plate (6). The spacer (72) is convex and has a flat portion (721). The flat portion (721) engages with the support plate (6) after the second pedal feel simulation spring (83) is compressed. The first pedal feel simulation spring (82) has a stiffness greater than that of the second pedal feel simulation spring (83).

6. The decoupled braking assist device according to claim 1, characterized in that, The axial guide rod (7) has a retaining ring (71) spaced apart from the support plate (6). A starting spring is located between the retaining ring (71) and the support plate (6). Multiple interconnected disc springs (891) are arranged radially inwardly on the starting spring. The starting power spring is provided with a first pedal feel simulation spring (82) and a second pedal feel simulation spring (83) on its radially inner side. The first end of the first pedal feel simulation spring (82) is connected to the retaining ring (71), and the second end of the first pedal feel simulation spring (82) is connected to the first bushing (74) sleeved on the axial guide rod (7). The first end of the second pedal feel simulation spring (83) is connected to the first bushing (74), and the second end of the second pedal feel simulation spring (83) is connected to the second bushing (75) sleeved on the axial guide rod (7). The first bushing (74) and the second bushing (75) can slide along the axial guide rod (7). In the initial state when the brake pedal is not pressed, the support plate (6), the second bushing (75), the first bushing (74), and the retaining ring (71) are all spaced apart.

7. The decoupled brake assist device according to claim 6, characterized in that, A starting power spring (23) is provided between the main shaft (21) and the input rod (1).

8. The braking assist device according to claim 6, characterized in that, The support member (25) includes a pair of support blocks symmetrically arranged on both sides of the plunger (2), with a gap between the pair of support blocks. The plunger (2), the disc spring assembly (87) or helical spring (88) at the end of the plunger (2), and the middle part (61) of the support plate are located in the gap between the pair of support blocks. A sensor bracket (93) connected to the plunger (2) extends out from the gap.

9. The braking assist device according to claim 1, characterized in that, The output push rod (5) has a return spring retainer (59) on its back side. The support plate (6) is located between the plunger (2) and the return spring retainer (59). In the event of failure of the power assist motor or the brake assist module, when the brake pedal is pressed, the plunger (2) directly pushes the support plate (6) to engage with the return spring retainer (59) on the back side of the output push rod (5). The movement of the support plate (6) directly drives the output push rod (5) to move axially, thereby outputting braking force to the brake cylinder.

10. A vehicle, characterized in that, The vehicle includes a decoupled brake assist device as described in any one of claims 1-9, wherein the decoupled brake assist device has two operating modes: decoupled and non-decoupled. When the brake pedal travel is less than the decoupling distance, the control unit of the decoupled brake assist device determines whether the brake assist motor works based on the current vehicle speed and the detected pedal travel. If the drag torque of the vehicle's main motor can meet the braking requirements at the current vehicle speed, the brake assist motor does not work, and braking is achieved by the drag torque of the vehicle's main motor. If the drag torque of the vehicle's main motor cannot meet the braking requirements at the current vehicle speed, the brake assist motor will respond to the displacement signal of the plunger (2) and start working to cooperate with the drag torque of the vehicle's main motor to achieve braking. When the brake pedal travel is greater than or equal to the decoupling distance, the control unit controls the brake booster motor to work based on the current vehicle speed and the detected displacement of the plunger (2), thereby pushing the brake master cylinder to build up pressure.

11. The vehicle according to claim 10, characterized in that, The vehicle in question is an electric vehicle.

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