A variable-damping pedal feel simulation mechanism for a brake-by-wire system

Abstract

The utility model relates to a line control technology field discloses a variable damping pedal feeling simulation mechanism suitable for line control system, simulation mechanism includes simulator casing and push rod, and the one end of push rod is used for being connected with brake pedal away from simulator casing, still includes variable damping component, and variable damping component includes: damping piston, is located in simulator casing inside sliding, damping pad, is pasted in the end face of damping piston closed end one side, elastic member, is located in damping pad closed end one side or with damping pad fixed, and elastic member is deformed to x direction springback under the action of external force and when external force is cancelled to y direction, damping piston is provided with at least part is covered by damping pad damping through -hole and is not interfered with damping pad through -hole, the utility model damping piston assembly axial reciprocation different direction fluid flow channel size difference produces different resistance force to brake pedal, thereby reaches " fast heavy, slow light " real pedal feeling simulation effect.

Description

Technical Field

[0001] This utility model relates to the field of brake-by-wire technology, and in particular to a variable damping pedal feel simulation mechanism suitable for brake-by-wire systems. Background Technology

[0002] Compared to traditional vacuum brake booster combined with hydraulic brake caliper systems, existing brake-by-wire technologies, including EHB (Electro-Hydraulic Braking) and ETBS (Electric Transmission Braking System), completely decouple the brake pedal from the caliper, preventing drivers from experiencing the same tactile feedback as hydraulic braking systems when pressing the brake pedal. Traditional vacuum brake boosters exhibit a lag-like pedal feel, characterized by light pressure on slow presses, heavier pressure on fast presses, and slow return. This lag increases with pedal displacement. Therefore, existing brake-by-wire systems often require a non-linear feedback force simulation unit composed of springs, rubber components, and other parts. However, existing pedal feel simulation methods cannot replicate the resistance felt when pressing the pedal quickly, resulting in unsatisfactory pedal feel performance. Therefore, some solutions add additional hysteresis components to approximate this effect. For example, Chinese patent CN119636660A, "A Dry Electronic Pedal Simulator with Hysteresis Characteristics," uses friction between a damping ring and a conical inner wall to provide hysteresis. However, the hysteresis provided by this dry friction method exhibits linear resistance characteristics, failing to achieve the consistency between slow and fast pedaling. Furthermore, repeated friction causes the damping ring to wear down, altering the friction characteristics and generating friction debris that pollutes the internal environment. Further, other solutions introduce a separate power source (motor, electromagnet) to generate additional reaction force on the brake pedal, resulting in a non-linear feedback force effect when the brake pedal is depressed. Examples include Chinese patents CN117549870A, "A Drive-by-Wire Chassis Pedal Simulator and Pedal Force Control Method," and CN115675404A, "Electric Pedal Simulator." However, this makes the product structure more complex and significantly increases product costs. Therefore, there is an urgent need to propose a pedal simulator structure and simulation method that is compatible with the existing brake-by-wire environment, requires no additional power source, and has the pedal feel of a traditional vacuum booster. Utility Model Content

[0003] This invention addresses the shortcomings of existing technologies by providing a variable damping pedal feel simulation mechanism suitable for brake-by-wire systems.

[0004] The present invention solves the above-mentioned technical problems through the following technical solution: A variable damping pedal feel simulation mechanism suitable for a brake-by-wire system includes a simulator housing and a push rod. The simulator housing has a closed end and an open end. The push rod is disposed at the open end of the simulator housing and can slide axially towards the closed end in the x-direction or towards the open end in the y-direction. The end of the push rod away from the simulator housing is used for connection with the brake pedal. The mechanism is characterized by further including a variable damping assembly, which comprises: A damping piston is slidably disposed inside the simulator housing. There is a first chamber between the damping piston and the closed end of the simulator housing, and a second chamber between the damping piston and the cover. The damping pad is attached to the end face of the closed end of the damping piston. An elastic member is located on one side of the closed end of the damping pad or fixed to the damping pad. Under the action of external force, the elastic member deforms in the y direction and rebounds in the x direction when the external force is removed. The push rod passes through the elastic member, the damping pad, and the damping piston, and the elastic member, the damping pad, and the damping piston are axially limited by the push rod; A return component is provided between the closed end of the simulator housing and the damping piston or push rod; The damping piston is provided with a fluid channel connecting the first chamber and the second chamber. The fluid channel includes a damping through hole that is at least partially covered by the damping pad and a through hole that is not interfered with by the damping pad. Under the application of external force, the push rod and the variable damping assembly move in the x direction to build up pressure, and the hydraulic oil flows from the first chamber to the second chamber through the through hole or through the through hole and the damping through hole. When the external force is canceled or less than the elastic force accumulated in the return component, the return component pushes the push rod and the variable damping assembly to move in the y-direction. The hydraulic pressure in the second chamber presses the damping pad against the damping through hole, thus hindering the push rod from retracting. The damping through hole is at least partially covered by the damping pad. Hydraulic oil flows from the second chamber back to the first chamber through the through hole and the damping through hole not covered by the damping pad. By pressing the pedal at different speeds, the speed of the damping piston also varies, causing the brake fluid to be compressed at different speeds. This generates different hydraulic feedback forces, resulting in differences in the deformation of the elastic component. Consequently, the opening of the fluid channel between the damping pad and the damping piston changes, thus obtaining different resistance sensations. This simulates the effect of a traditional pedal: light pressure when pressed quickly and heavy pressure when pressed slowly. This simulation relies on the hydraulic pressure generated by the brake fluid itself due to the size of the flow channel opening, resulting in a stable structure and accurate simulation.

[0005] Preferably, the damping piston is cylindrical, with a through hole axially arranged on the outer wall of the damping piston connecting the first chamber and the second chamber. The side wall of the damping piston is also circumferentially provided with an annular groove, making the axial cross-section of the damping piston I-shaped. Several damping through holes are concentrically arranged and pass through the damping piston on both end faces of the damping piston. The groove wall of the annular groove is provided with a through hole that passes through the inner cavity of the damping through hole of the damping piston and the outer space of the annular groove. The damping pad covers or partially covers one side of the opening end of the damping through hole. Partial coverage can be achieved by the damping pad being semi-sealed with pores for fluid passage; or by the damping pad being annular, with the distance from the outer edge of the damping through hole to the center of the damping piston being greater than the radius of the outer edge of the damping pad; or by other similar positional relationships resulting in the damping pad not fully covering the damping through hole.

[0006] Preferably, the open end of the damping piston is provided with a receiving cavity for accommodating the damping pad. The bottom shape of the receiving cavity matches the damping pad. The damping pad is placed inside the receiving cavity, and the bottom of the receiving cavity prevents the damping pad from bending and deforming in the x-direction and keeps it covering the outside of the damping through hole. When the return component releases elastic potential energy to move the push rod in the y-direction, the hydraulic oil in the second chamber generates a reverse force in the x-direction on the push rod. By utilizing the cooperation between the damping piston and the variable damping assembly to achieve a bidirectional flow channel difference, a slow retraction effect is achieved.

[0007] Preferably, the return component includes a first spring and a second spring, which are connected in series in the second chamber to provide feedback force corresponding to the pedal stroke. The closed end of the simulator housing has a boss protruding towards the open end. The first spring and the second spring are connected in series via a spring washer, which slides outside the boss. One end of the second spring is fixedly connected to the inner wall of the closed end of the simulator housing, and the other end abuts against the spring washer. One end of the first spring abuts against the damping piston, and the other end abuts against the spring washer. A non-linear spring force is provided. In the initial stroke, the second spring participates. Due to the low stiffness of the second spring, the pedal force increases gradually. When the limit step is reached, the second spring is compressed to its maximum stroke. At this point, the elastic force of the second spring is fixed, requiring a greater pedal force to compress the first spring.

[0008] Preferably, the outer surface of the boss is provided with a limiting step to restrict the continued compression of the second spring. The stiffness of the first spring is greater than that of the second spring. The compression of the first spring and the second spring along the x-direction provides feedback force corresponding to the stroke of the push rod and the pedal.

[0009] Preferably, the boss has an internal cavity on one side of the open end, and a buffer block is fitted inside the cavity. An impact head is threadedly connected to the closed end of the push rod. The extension length of the impact head is locked by an adjusting nut. The buffer block, in conjunction with the impact head, provides a soft limit when the push rod reaches the bottom. The impact head is threaded into a threaded hole on the left end of the push rod, and its position is fixed by an adjusting nut. The extension length of the impact head from the push rod can be adjusted by the adjusting nut to meet different pedal travel requirements.

[0010] Preferably, the push rod includes a concentric shaft portion, and a stepped surface is provided on one side of the open end of the concentric shaft portion. The concentric shaft portion passes through the elastic member, the damping pad, and the damping piston. The variable damping assembly is fixed by the stepped surface in conjunction with a retaining spring or bolts.

[0011] Preferably, the damping pad consists of a flexible part and an insert part. The flexible part is a single or multi-layer fully sealed soft material or a semi-sealed soft material with micro-gaps. The insert part is rigid and has a central hole in the center, which can accommodate the concentric shaft part of the push rod through.

[0012] Preferably, the elastic member has a mounting hole at its center, and elastic arms are arranged around the periphery of the mounting hole, extending radially outward from the mounting hole. This shape makes the inner periphery of the elastic member less prone to deformation, while the outer periphery is more easily deformed, facilitating changes in the opening degree of the damping pad and damping spring.

[0013] Preferably, the closed end of the simulator housing is fitted with a cover, and a sealing damping ring for damping piston shock absorption is installed between the cover and the variable damping assembly. A sealing ring for axial sealing of the push rod is installed between the push rod and the cover. This utility model, by adopting the above technical solution, has significant technical effects: 1. The combination of a damping pad made of flexible material and an elastic component can use hydraulic pressure to deform the elastic component according to the speed when the brake pedal is pressed, thereby adjusting the gap between the damping pad and the damping piston to generate different sizes of pedal resistance force and achieve a variable damping effect in the brake pedal feel. 2. By changing the number of layers of the elastic component or selecting elastic components of different thicknesses, the deformation of the elastic component can be adjusted when the brake pedal is pressed at the same speed. This changes the opening size of the gap between the damping pad and the damping piston, allowing the pedal resistance to be adjusted according to the user's needs. 3. The different sizes of the fluid flow channels in the axial reciprocating direction of the damping piston assembly produce different resistance forces on the brake pedal, thereby achieving a realistic pedal feel simulation effect of "heavy pressure when pressing fast and light pressure when pressing slow". 4. When the pedal is released, the elastic component presses the damping pad tightly against the damping piston and provides the damping pad to resist the elastic force of the hydraulic oil generated by compression, thereby achieving the effect of "slow rebound". Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model when the brake pedal is not pressed; Figure 2 This is a schematic diagram of the structure of this utility model when the brake pedal is depressed; Figure 3 This is an exploded view of this utility model; Figure 4 It is an exploded view of the push rod and the variable damping assembly; Figure 5 This is a schematic diagram of the push rod and variable damping assembly when the brake pedal is pressed. Figure 6 This is a schematic diagram of the push rod and variable damping assembly when the brake pedal is released; Figure 7 This is a schematic diagram of the structure where the damping piston is located on the closed side; Figure 8 This is a schematic diagram of the structure where the damping piston is located on the open side; Figure 9 This is a schematic diagram showing the effect of pressing the brake pedal with the same force after the thickness of the elastic component changes. Figure 10 This is a schematic diagram of the structure of the damping pad and elastic component integrated in Example 2; Figure 11 yes Figure 10 A schematic diagram of the structure on the other side; Figure 12 yes Figure 10 A partial sectional view.

[0015] The parts referred to by the numbers in the above attached figures are as follows: 1. Push rod; 11. Impact head; 12. Adjusting nut; 13. Concentric shaft; 14. Stepped surface; 15. Snap ring; 2. Cover; 21. Sealing damping ring; 22. Sealing ring; 3. Simulator housing; 31. First chamber; 32. Second chamber; 33. Boss; 331. Limiting step; 332. Inner hole of the cavity; 333. Buffer block; 4. Damping piston; 41. Damping through hole; 42. Through hole; 43. Annular groove; 44. Accommodating cavity; 5. Damping pad; 51. Flexible part; 52. Insert part; 6. Elastic component; 61. Elastic arm; 62. Mounting hole; 71. First spring; 72. Second spring; 8. Spring washer. Detailed Implementation

[0016] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0017] Example 1 like Figure 1-2 As shown, a variable damping pedal feel simulation mechanism suitable for a brake-by-wire system includes a simulator housing 3 and a push rod 1. The simulator housing 3 has a closed end and an open end. The push rod 1 is disposed at the open end of the simulator housing 3. The inner cavity of the simulator housing 3 is filled with fluid that provides damping force; for convenience, this refers specifically to hydraulic oil. The push rod 1 can slide axially towards the closed end in the x-direction or towards the open end in the y-direction. The end of the push rod 1 away from the simulator housing 3 is used to connect to the brake pedal.

[0018] like Figure 1-4 As shown, it also includes a variable damping component, which includes: The damping piston 4 is slidably disposed inside the simulator housing 3. There is a first chamber 31 between the damping piston 4 and the closed end of the simulator housing 3, and a second chamber 32 between the damping piston 4 and the cover 2. Damping pad 5 is attached to the end face of the closed end of damping piston 4; The elastic member 6 is located on one side of the closed end of the damping pad 5. Under the action of external force, the elastic member 6 deforms in the y direction and rebounds in the x direction when the external force is removed.

[0019] Push rod 1 passes through elastic member 6, damping pad 5, and damping piston 4. Elastic member 6, damping pad 5, and damping piston 4 are axially limited by push rod 1. There are one or more elastic members 6, and the thickness of elastic member 6 is adjustable. By replacing the elastic member, the preload on damping pad 5 is changed, thereby adjusting the fast-step resistance threshold.

[0020] A return component is provided between the closed end of the simulator housing 3 and the damping piston 4 or push rod 1; As one possible implementation method, such as Figure 4 As shown, the push rod 1 includes a concentric shaft portion 13. A stepped surface 14 is provided on one side of the open end of the concentric shaft portion 13. The concentric shaft portion 13 passes through the elastic member 6, the damping pad 5, and the damping piston 4. The variable damping assembly is fixed by the stepped surface 14 in conjunction with a retaining spring 15 or bolts. A retaining spring groove is provided at the end of the concentric shaft portion of the push rod, and a retaining spring 15 is provided in the retaining spring groove. The retaining spring 15 cooperates with the stepped surface 14 to axially lock the damping piston, damping pad, and elastic member for fixation. The concentric shaft portion 13 is used for circumferential positioning of the damping piston, damping pad, and elastic member.

[0021] The damping piston 4 is provided with a fluid channel connecting the first chamber 31 and the second chamber 32. The fluid channel includes a damping through hole 41 that is at least partially covered by the damping pad 5 and a through hole 42 that is not interfered with by the damping pad 5. like Figure 5As shown, under the application of external force, the push rod 1 and the variable damping assembly move in the x direction to build up pressure, and the hydraulic oil flows from the first chamber 31 to the second chamber 32 through the through hole 42 or through the through hole 42 and the damping through hole 41. like Figure 6 As shown, when the external force is canceled or less than the elastic force accumulated by the return component, the return component pushes the push rod 1 and the variable damping assembly to move in the y direction. The hydraulic pressure in the second chamber 32 presses the damping pad 5 against the damping through hole 41, thereby hindering the push rod 1 from retracting. The damping through hole 41 is at least partially covered by the damping pad 5. The hydraulic oil flows from the second chamber 32 back to the first chamber 31 through the through hole 42 and the damping through hole 41 that is not covered by the damping pad 5.

[0022] like Figure 7-8 As shown, the damping piston 4 is cylindrical. A through hole 42 is axially provided on the outer wall of the damping piston 4, connecting the first chamber 31 and the second chamber 32. An annular groove 43 is also circumferentially provided on the side wall of the damping piston 4, making the axial cross-section of the damping piston 4 I-shaped. Several damping through holes 41 are concentrically arranged and penetrating the damping piston 4 on both end faces of the damping piston 4. Through holes 42 are provided on the walls of the annular groove 43, penetrating the inner cavity of the damping through hole 41 and the outer space of the annular groove 43. The damping pad 5 covers or partially covers one side of the opening end of the damping through hole 41. Partial coverage can be achieved by the damping pad 5 being semi-sealed with pores for fluid passage; or by the damping pad 5 being annular, with the distance from the outer edge of the damping through hole 41 to the center of the damping piston 4 being greater than the radius of the outer edge of the damping pad 5; or by other similar positional relationships resulting in the damping pad 5 not fully covering the damping through hole 41.

[0023] The open end of the damping piston 4 is provided with a receiving cavity 44 for accommodating the damping pad 5. The bottom shape of the receiving cavity 44 matches the damping pad 5. The damping pad 5 is placed inside the receiving cavity 44. The bottom of the receiving cavity 44 prevents the damping pad 5 from bending and deforming in the x-direction and keeps it covering the outside of the damping through hole 41. When the return component releases elastic potential energy to move the push rod 1 in the y-direction, the hydraulic oil in the second chamber 32 generates a reverse force in the x-direction on the push rod 1. As one embodiment, the side of the damping pad 5 located at the closed end is flat, so the end face of the damping piston 4 located at the open end is also flat.

[0024] The return component includes a first spring 71 and a second spring 72, which are connected in series in the second chamber 32 to provide feedback force corresponding to the pedal stroke. The closed end of the simulator housing 3 has a boss 33 protruding towards the open end. The first spring 71 and the second spring 72 are connected in series through a spring washer 8, which slides outside the boss 33. One end of the second spring 72 is fixedly connected to the inner wall of the closed end of the simulator housing 3, and the other end abuts against the spring washer 8. One end of the first spring 71 abuts against the damping piston 4, and the other end abuts against the spring washer 8.

[0025] The outer surface of the boss 33 is provided with a limiting step 331 to restrict the second spring 72 from continuing to compress. The stiffness of the first spring 71 is greater than that of the second spring 72. The first spring 71 and the second spring 72 are compressed along the x-direction to provide feedback force corresponding to the push rod 1 and the pedal stroke.

[0026] The boss 33 has an inner cavity 332 on one side of the open end, and a buffer block 333 is fitted inside the inner cavity 332. An impact head 11 is threadedly connected to the push rod 1 on the closed end side. The extension length of the impact head 11 is locked by an adjusting nut 12. The buffer block 333, in conjunction with the impact head 11, provides a soft limit when the push rod 1 reaches its bottom. The impact head 11 and the adjusting nut 12 are connected; the end of the impact head 11 is designed as a contact part that impacts the buffer block 333, and it can be screwed into the threaded hole at the end of the push rod 1. The thread direction of the adjusting nut 12's inner hole is opposite to that of the impact head 11, which allows it to fix the extension position of the impact head in the axial direction. The impact head 11 abuts against the buffer block 333 at the maximum stroke of the push rod, and the extension position of the impact head can be used to adjust the brake pedal stroke.

[0027] like Figure 4 As shown, the damping pad 5 consists of a flexible part 51 and an insert part 52. The flexible part 51 is a single-layer or multi-layer fully sealed soft material or a semi-sealed soft material with micro-gaps. The insert part 52 is rigid and has a central hole 53 in the center, which can accommodate the concentric shaft part 13 of the push rod 1 through which it passes. The material for the flexible part 51 can be a sealing material such as rubber, a semi-sealed material, or a sealing material with small holes, as needed. The key is to ensure that the flexible part itself has flexible properties, allowing it to deform under hydraulic pressure. The damping force generated by the hydraulic oil on the damping pad 5 is adjusted; the smaller the gaps on the material surface, the greater the damping force generated by the damping pad.

[0028] like Figure 4 As shown, the elastic member 6 has a mounting hole 62 at its center, and an elastic arm 61 is provided on the outer periphery of the mounting hole 62. The elastic arm 61 extends outward from the mounting hole 62 in a radial pattern.

[0029] like Figure 1 and Figure 3 As shown, a cover 2 is installed at the closed end of the simulator housing 3. A sealing damping ring 21 for damping piston 4 is installed between the cover 2 and the variable damping assembly. A sealing ring 22 for axial sealing of push rod 1 is installed between push rod 1 and cover 2. The working principle of the brake pedal simulation is as follows: When the brake pedal is pressed at different speeds, the reverse force generated by the hydraulic oil on the damping pad is different. The faster the push rod moves, the greater the reverse force generated by the hydraulic oil on the damping pad. At the same time, the gap between the damping pad and the damping piston due to the deformation of the damping pad is larger, thus realizing the variable damping function in the brake pedal simulator of this patent. In particular, the reverse force generated by the damping pad 6 can be easily increased by increasing the elastic force of the elastic member 6. like Figure 5-6 As shown, the variable damping pedal feel simulation method employs a variable damping pedal feel simulation mechanism, and the method is as follows: A: When the speed is S x When the brake pedal is depressed, the force exerted by the brake pedal on push rod 1 in the x-direction is denoted as F. c The axial movement of the push rod 1, which is linked to the brake pedal, along with the movement of the damping assembly in the x direction to build up pressure, allows hydraulic oil to flow from the first chamber 31 to the second chamber 32 through the through hole 42 or through the through hole 42 and the damping through hole 41. The compression of the return component generates a force F in the y-direction on push rod 1, which corresponds to the stroke of push rod 1. y The damping pad 5 and the elastic member 6 block the flow of hydraulic oil, and the hydraulic oil generates a reverse force on the push rod 1 in the y direction, denoted as F. X ; The resistance force F fed back to the brake pedal z =F y +F X +a;F z Less than F c ; 'a' represents the resistance force caused by other factors such as friction, and 'a' can be a variable number or a constant. Specifically, during the brake pedal return process, the reverse force of the hydraulic oil on the damping piston consumes, to some extent, the reverse force of the elastic potential energy of the return component on the push rod. Therefore, the feedback force of the brake pedal on the driver's foot at this time will be less than the force applied when the brake pedal is pressed, thus providing a better pedal feel.

[0030] like Figure 9 As shown, the velocity S of push rod 1 x The boundary velocity S not greater than that of hydraulic damping n At that time, hydraulic oil flows from the first chamber 31 to the second chamber 32 through the through hole 42; the speed S of push rod 1 x Greater than S nAt that time, hydraulic oil flows from the first chamber 31 to the second chamber 32 through the through hole 42 and the damping through hole 41. The resistance F of the hydraulic oil... X The deformation of the damping pad 5 varies with the velocity S of the push rod 1. x The resistance force F, which increases with the increase of [something], is fed back to the brake pedal. z Increase; of which, S n It can be a preset value of 0 or higher.

[0031] B: When the brake pedal is released, push rod 1 loses the external force input from the brake pedal. The return component releases the elastic potential energy generated by compression, pushing push rod 1 and the variable damping assembly back in the y-direction. The y-direction force exerted by the return component on push rod 1 is F, which corresponds to the stroke of push rod 1. y The damping through-hole 41 is at least partially covered by the damping pad 5. Hydraulic oil flows from the second chamber 32 back to the first chamber 31 through the through-hole 42 and the damping through-hole 41 not covered by the damping pad 5. The hydraulic oil in the second chamber 32 generates a reverse force F in the x-direction on the push rod 1. T Used to prevent push rod 1 from retracting in the y direction; Among them, F X F z and F T They are positively correlated with the elastic force of elastic member 6.

[0032] Example 2 Its structural embodiment 1, such as Figure 10-12 As shown, the only difference is that the elastic member 6 is fixed to the damping pad 5. In one embodiment, the elastic member 6 and the damping pad 5 are processed as a single unit. The end face of the damping pad 5 on the closed side is flat, and a reinforcing frame is provided on the other side. A radially arranged elastic member 6 is embedded in the center of the damping pad 5, and the elastic arm of the elastic member extends into the reinforcing frame for fixation. The working principle is the same as in embodiment 1.

[0033] In the description of this utility model, it should be understood that the terms "center," "length," "width," "thickness," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0034] In summary, the above description is only a preferred embodiment of the present utility model. All equivalent changes and modifications made within the scope of the patent application of the present utility model shall fall within the scope of the patent of the present utility model.

Claims

1. A variable damping pedal feel simulation mechanism suitable for a brake-by-wire system, comprising a simulator housing (3) and a push rod (1), the simulator housing (3) having a closed end and an open end, the push rod (1) being disposed at the open end of the simulator housing (3), the push rod (1) being axially sliding towards the closed end in the x-direction or towards the open end in the y-direction, the end of the push rod (1) away from the simulator housing (3) being used for connection with the brake pedal; characterized in that, It also includes a variable damping component, which includes: The damping piston (4) is slidably disposed inside the simulator housing (3). There is a first chamber (31) between the damping piston (4) and the closed end of the simulator housing (3), and a second chamber (32) between the damping piston (4) and the cover (2). The damping pad (5) is attached to the end face of the closed end of the damping piston (4); The elastic member (6) is located on one side of the closed end of the damping pad (5) or fixed to the damping pad (5). Under the action of external force, the elastic member (6) deforms in the y direction and rebounds in the x direction when the external force is removed. The push rod (1) passes through the elastic member (6), the damping pad (5), and the damping piston (4), and the elastic member (6), the damping pad (5), and the damping piston (4) are axially limited by the push rod (1); A return component is provided between the closed end of the simulator housing (3) and the damping piston (4) or push rod (1); The damping piston (4) is provided with a fluid channel connecting the first chamber (31) and the second chamber (32). The fluid channel includes a damping through hole (41) at least partially covered by the damping pad (5) and a through hole (42) that is not interfered with by the damping pad (5). Under the application of external force, the push rod (1) and the variable damping assembly move in the x direction to build up pressure, and the hydraulic oil flows from the first chamber (31) to the second chamber (32) through the through hole (42) or through the through hole (42) and the damping through hole (41). When the external force is canceled or less than the elastic force accumulated by the return component, the return component pushes the push rod (1) and the variable damping component to move in the y direction. The hydraulic pressure in the second chamber (32) presses the damping pad (5) against the damping through hole (41) to prevent the push rod (1) from retracting. The damping through hole (41) is at least partially covered by the damping pad (5). The hydraulic oil flows from the second chamber (32) back to the first chamber (31) through the through hole (42) and the damping through hole (41) not covered by the damping pad (5).

2. The variable damping pedal feel simulation mechanism for a brake-by-wire system according to claim 1, characterized in that: The damping piston (4) is cylindrical. A through hole (42) is provided axially on the outer side wall of the damping piston (4) to connect the first chamber (31) and the second chamber (32). The side wall of the damping piston (4) is also provided with an annular groove (43) in the circumferential direction so that the axial cross section of the damping piston (4) is I-shaped. Several damping through holes (41) are provided on both sides of the damping piston (4) and are arranged concentrically and pass through the damping piston (4). The damping through hole (41) and the groove wall of the annular groove (43) are provided with a through hole (42) that passes through the inner cavity of the damping through hole (41) of the damping piston (4) and the outer space of the annular groove (43). The damping pad (5) covers or partially covers one side of the opening end of the damping through hole (41).

3. A variable damping pedal feel simulation mechanism for a brake-by-wire system according to claim 1 or 2, characterized in that: The damping piston (4) has an opening end with a receiving cavity (44) for receiving the damping pad (5). The bottom shape of the receiving cavity (44) matches the damping pad (5). The damping pad (5) is placed in the receiving cavity (44). The bottom of the receiving cavity (44) prevents the damping pad (5) from bending and deforming in the x direction and keeps it covered outside the damping through hole (41). When the return component releases elastic potential energy to move the push rod (1) in the y direction, the hydraulic oil in the second chamber (32) generates a reverse force in the x direction on the push rod (1).

4. The variable damping pedal feel simulation mechanism for a brake-by-wire system according to claim 1, characterized in that: The return component includes a first spring (71) and a second spring (72). The first spring (71) and the second spring (72) are connected in series in the second chamber (32) to provide feedback force corresponding to the pedal stroke. The closed end of the simulator housing (3) has a boss (33) protruding towards the open end. The first spring (71) and the second spring (72) are connected in series through a spring washer (8). The spring washer (8) slides outside the boss (33). One end of the second spring (72) is fixedly connected to the inner wall of the closed end of the simulator housing (3), and the other end abuts against the spring washer (8). One end of the first spring (71) abuts against the damping piston (4), and the other end abuts against the spring washer (8).

5. A variable damping pedal feel simulation mechanism for a brake-by-wire system according to claim 4, characterized in that: The outer surface of the boss (33) is provided with a limiting step (331) to limit the continued compression of the second spring (72). The stiffness of the first spring (71) is greater than that of the second spring (72). The first spring (71) and the second spring (72) are compressed along the x direction to provide feedback force corresponding to the push rod (1) and the pedal stroke.

6. A variable damping pedal feel simulation mechanism for a brake-by-wire system according to claim 4, characterized in that: The boss (33) has a cavity inner hole (332) on one side of the open end. A buffer block (333) is installed in the cavity inner hole (332). The push rod (1) has an impact head (11) threaded on one side of the closed end. The extension length of the impact head (11) is locked by adjusting the nut (12). The buffer block (333) cooperates with the impact head (11) to provide a soft limit when the push rod (1) moves to the bottom.

7. A variable damping pedal feel simulation mechanism for a brake-by-wire system according to claim 1, characterized in that: The push rod (1) includes a concentric shaft part (13). A stepped surface (14) is provided on one side of the open end of the concentric shaft part (13). The concentric shaft part (13) passes through the elastic member (6), the damping pad (5) and the damping piston (4). The variable damping assembly is fixed by the stepped surface (14) in conjunction with the snap ring (15) or bolts.

8. A variable damping pedal feel simulation mechanism for a brake-by-wire system according to claim 1, characterized in that: The damping pad (5) consists of a flexible part (51) and an insert part (52). The flexible part (51) is a single or multi-layer fully sealed soft material or a semi-sealed soft material with micro-gaps. The insert part (52) is rigid. The insert part (52) has a central hole (53) in the center. The central hole (53) can accommodate the concentric shaft part (13) of the push rod (1) through which it passes.

9. A variable damping pedal feel simulation mechanism for a brake-by-wire system according to claim 1, characterized in that: The elastic member (6) has a mounting hole (62) at its center and an elastic arm (61) on its outer periphery. The elastic arm (61) extends outward from the mounting hole (62) in a radial pattern.

10. A variable damping pedal feel simulation mechanism for a brake-by-wire system according to claim 1, characterized in that: The closed end of the simulator housing (3) is fitted with a cover (2), and a sealing damping ring (21) for damping piston (4) is installed between the cover (2) and the variable damping assembly. A sealing ring (22) for axial sealing of push rod (1) is installed between push rod (1) and cover (2).

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