An anti-jamming pressure building unit, an anti-jamming design method, and a working method.

Abstract

This invention discloses an anti-jamming pressure build-up unit, an anti-jamming design method, and a working method, belonging to the field of automotive braking. The anti-jamming pressure build-up unit includes a motor and a ball screw assembly. The ball screw assembly includes a screw rod fastened to the motor rotor and a nut threadedly engaged with the screw rod. The nut is fastened to a PSU piston. An anti-jamming component is provided on the opposite side of the nut and the rotor. The anti-jamming component includes a first protrusion on the end face of the nut facing the rotor and a second protrusion on the end face of the rotor facing the nut. This is used to ensure that the first and second protrusions make early contact when the motor drives the nut back via the screw, preventing the motor from jamming due to direct contact between the nut and the rotor. By using the above-mentioned anti-jamming pressure build-up unit, anti-jamming design method, and working method, the motor jamming is prevented by the early contact of the two protrusions on the opposite side of the nut and the rotor during the return stroke.

Description

Technical Field

[0001] This invention relates to the field of automotive braking technology, and in particular to an anti-jamming pressure build-up unit, an anti-jamming design method, and a working method. Background Technology

[0002] EHB (Electro-Hydraulic Brake) is a braking system that integrates electronic control technology with hydraulic actuators. It is widely used in modern automobiles, playing a crucial role, especially in new energy vehicles and intelligent driving vehicles. The core advantage of this system lies in its extremely fast braking response: the transmission speed of electronic signals is significantly faster than traditional mechanical or hydraulic transmission methods, reducing the response delay from when the driver presses the brake pedal to when the system outputs braking force to less than 100 milliseconds, while the response delay of traditional braking systems is typically 200-300 milliseconds. This characteristic effectively shortens braking distance in emergency braking scenarios, significantly improving driving safety.

[0003] The core component of the EHB system is the PSU (Pressure Supply Unit), which mainly consists of a ball screw, a motor, and a PSU piston. The working principle of this unit is as follows: when the motor rotates, the rotational motion is converted into axial driving force through the ball screw, thereby realizing the pressure build-up and pressure reduction of the braking system; during pressure build-up, the driving force pushes the PSU piston in a specific direction to establish braking pressure; during pressure reduction, the driving force acts in the opposite direction to reset the relevant components and release the pressure.

[0004] However, when the system completes pressure build-up and enters the pressure reduction process, the ball screw nut will return under the drive of the motor. During this process, the rear end face of the nut is prone to contact with the bottom surface of the motor rotor and generate friction, which creates a tightening torque. When this tightening torque exceeds the motor's maximum operating torque, it can cause the motor to seize during subsequent pressure build-up (during pressure build-up, the motor rotates in reverse, and because the tightening torque exceeds the motor's maximum operating torque, the motor cannot overcome the tightening torque, causing it to seize). This can prevent the electro-hydraulic braking system from operating normally, and in severe cases, can lead to traffic accidents. Summary of the Invention

[0005] The purpose of this invention is to provide an anti-jamming pressure building unit, an anti-jamming design method, and an operating method to solve the above-mentioned technical problems.

[0006] To achieve the above objectives, the present invention provides an anti-jamming pressure building unit, comprising a motor and a ball screw assembly connected to the power output end of the motor. The ball screw assembly includes a screw rod fastened to the rotor of the motor and a nut threadedly engaged with the screw rod. The nut is fastened to a PSU piston. An anti-jamming component is provided on the opposite side of the nut and the rotor. The anti-jamming component includes a first protrusion respectively provided on the end face of the nut facing the rotor and a second protrusion respectively provided on the end face of the rotor facing the nut. This component is used to ensure that the first protrusion and the second protrusion make contact in advance when the motor drives the nut to return via the screw rod, thereby preventing the motor from jamming due to direct contact between the nut and the rotor.

[0007] Preferably, the first protrusion and the nut are integrally formed and made of the same material;

[0008] The second protrusion is integrally formed with the rotor and is made of the same material.

[0009] A method for anti-jamming design of an anti-jamming pressure build-up unit includes the following steps:

[0010] S1. Define the circumferential angle reference: Taking the end of the thread on the nut as the circumferential 0° reference line, set the angle of the first protrusion as... Simultaneously, taking the starting point of the thread on the screw as a circumferential 0° reference, the angle of the second protrusion is set as... ;

[0011] S2. Obtain the following key parameters: lead of the ball screw assembly. and the effective thread length of the ball screw assembly ;

[0012] S3. Decompose the relative rotation number of the screw and nut into integer parts. and decimal part :

[0013] ;

[0014] In the formula, Indicates the rounding operation;

[0015] This leads to the circumferential rotational deviation. ;

[0016] S4. Calculate the total phase angle of the second protrusion relative to the starting edge of the screw thread. :

[0017] ;

[0018] S5. Calculate the angle of the first protrusion in intervals. :

[0019] ;

[0020] S6, according to angle and angle The first protrusion and the second protrusion are integrally machined on the rotor and the nut, respectively.

[0021] A working method for an anti-jamming pressure-building unit includes pressure building and return stroke. During pressure building, the motor drives the rotor to rotate in the forward direction, which in turn drives the screw to rotate. At this time, under the action of the screw and the nut, the nut is driven to move along the screw axis, thereby driving the PSU piston to extend and compress the brake fluid to build pressure.

[0022] During the return stroke, the motor drives the rotor to rotate in the opposite direction, which in turn drives the screw to rotate in the opposite direction, thereby causing the nut and PSU piston to move in the opposite direction, releasing the braking pressure until the first protrusion on the nut and the second protrusion on the rotor make rigid contact, preventing the nut from moving further. At this time, there is a safe gap between the first protrusion and the rotor and between the second protrusion and the nut, waiting for the next pressure build-up.

[0023] Therefore, the present invention, by employing the above-mentioned anti-jamming pressure building unit, anti-jamming design method, and working method, has the following beneficial effects:

[0024] 1. Effectively solves the jamming problem: By adding an integrated protrusion to the bottom of the motor rotor and the rear end of the ball screw nut, the two can make contact in advance when the nut returns, avoiding direct contact and friction between the rear end face of the nut and the bottom surface of the motor rotor to generate tightening torque, preventing the motor from jamming, ensuring the normal operation of the EHB system, and improving driving safety.

[0025] 2. Strong product compatibility: It does not change the original overall structure and assembly logic of the pressure building unit, and can be adapted to existing systems without the need for major adjustments to other components;

[0026] 3. Small size and high strength: The protrusion is integrally machined with the motor rotor and nut, without increasing the structural volume, while ensuring the overall structural strength;

[0027] 4. Low processing difficulty and low cost: The protrusion can be processed simultaneously with the original part, without the need for complex processes, which reduces processing difficulty and production costs.

[0028] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0029] Figure 1 This is a cross-sectional view of an anti-jamming pressure-building unit according to the present invention;

[0030] Figure 2 This is a schematic diagram of the return stroke of an anti-jamming pressure building unit according to the present invention;

[0031] Figure 3This is an axial cross-sectional view of the first and second protrusions when the anti-jamming pressure building unit of the present invention returns to its position.

[0032] Figure 4 This is a radial cross-sectional view of the first and second protrusions when the anti-jamming pressure building unit of the present invention returns to its position.

[0033] Figure 5 This is a schematic diagram of the nut structure of an anti-jamming pressure building unit according to the present invention;

[0034] Figure 6 This is a schematic diagram of the rotor structure of an anti-jamming pressure building unit according to the present invention;

[0035] Figure 7 This is a schematic diagram showing the first protrusion angle setting of an anti-jamming pressure building unit according to the present invention;

[0036] Figure 8 This is a schematic diagram showing the setting of the second protrusion angle of an anti-jamming pressure building unit according to the present invention.

[0037] Figure Labels

[0038] 1. Motor; 11. Rotor; 111. Second protrusion; 2. Ball screw assembly; 21. Screw; 22. Nut; 221. First protrusion; 3. PSU piston. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of the present invention and are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0040] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process, method, system, product, or server that includes a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0041] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0042] like Figures 1-8As shown, an anti-jamming pressure building unit includes a motor 1 and a ball screw assembly 2 connected to the power output end of the motor 1. The ball screw assembly 2 includes a screw 21 fastened to the rotor 11 of the motor 1 and a nut 22 threadedly engaged with the screw 21. The nut 22 is fastened to a PSU piston 3. An anti-jamming component is provided on the opposite side of the nut 22 and the rotor 11. The anti-jamming component includes a first protrusion 221 respectively provided on the end face of the nut 22 facing the rotor 11 and a second protrusion 111 provided on the end face of the rotor 11 facing the nut 22. When the motor 1 drives the nut 22 back through the screw 21, the first protrusion 221 and the second protrusion 111 make contact in advance (the side of the first protrusion 221 and the side of the second protrusion 111 contact each other to prevent the nut 22 from continuing to move), thus avoiding the motor 1 from jamming due to direct contact between the nut 22 and the rotor 11. The first protrusion 221 is integrally formed with the nut 22 and is made of the same material; the second protrusion 111 is integrally formed with the rotor 11 and is made of the same material. In this embodiment, the screw 21 and the rotor 11 are fastened together with screws.

[0043] A method for anti-jamming design of an anti-jamming pressure build-up unit includes the following steps:

[0044] S1. Define the circumferential angle reference: Taking the end of the thread on the nut 22 as the circumferential 0° reference line, set the angle of the first protrusion 221 as... That is, the circumferential angle of the first protrusion relative to the starting point of the nut thread is Simultaneously, taking the starting point of the thread on screw 21 as a circumferential 0° reference, the angle of the second protrusion 111 is set as... That is, the circumferential angle of the second protrusion relative to the starting point of the screw thread is ;

[0045] S2. Obtain the following key parameters: Lead of ball screw assembly 2 and the effective thread length of ball screw assembly 2 ;

[0046] S3. Divide the relative number of rotations of screw 21 and nut 22 into integer parts. and decimal part :

[0047] ;

[0048] In the formula, Indicates the rounding operation;

[0049] This leads to the circumferential rotational deviation. ;

[0050] S4. Calculate the total phase angle of the second protrusion 111 relative to the thread start edge of the screw 21. :

[0051] ;

[0052] S5. Calculate the angle of the first protrusion at 221 degrees in intervals. :

[0053] ;

[0054] S6, according to angle and angle The first protrusion 221 and the second protrusion 111 are integrally machined on the rotor 11 and the nut 22, respectively.

[0055] A working method of an anti-jamming pressure building unit includes pressure building and return stroke. During pressure building, the motor 1 drives the rotor 11 to rotate in the forward direction, which in turn drives the screw 21 to rotate. At this time, under the action of the screw 21 and the nut 22, the nut 22 is driven to move along the axial direction of the screw 21, thereby driving the PSU piston 3 to extend and compress the brake fluid to build pressure.

[0056] During the return stroke, motor 1 drives rotor 11 to rotate in the opposite direction, which in turn drives screw 21 to rotate in the opposite direction, thereby causing nut 22 and PSU piston 3 to move in the opposite direction, releasing braking pressure until the first protrusion 221 on nut 22 and the second protrusion 111 on rotor 11 make rigid contact, preventing nut 22 from moving further. At this time, there are safety gaps between the first protrusion 221 and rotor 11 and between the second protrusion 111 and nut 22, waiting for the next pressure build-up.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for anti-jamming design of an anti-jamming pressure-building unit, characterized in that: The anti-jamming pressure building unit includes a motor and a ball screw assembly connected to the power output end of the motor. The ball screw assembly includes a screw rod that is fastened to the rotor of the motor and a nut that is threadedly engaged with the screw rod. The nut is fastened to the PSU piston. An anti-jamming component is provided on the opposite side of the nut and the rotor. The anti-jamming component includes a first protrusion provided on the end face of the nut facing the rotor and a second protrusion provided on the end face of the rotor facing the nut. When the motor drives the nut to return via the screw, the first protrusion and the second protrusion make contact in advance to avoid the motor jamming caused by direct contact between the nut and the rotor. The first protrusion is integrally formed with the nut and is made of the same material; the second protrusion is integrally formed with the rotor and is made of the same material. The anti-jamming design method includes the following steps: S1. Define the circumferential angle reference: Taking the end of the thread on the nut as the circumferential 0° reference line, set the angle of the first protrusion as... Simultaneously, taking the starting point of the thread on the screw as a circumferential 0° reference, the angle of the second protrusion is set as... ; S2. Obtain the following key parameters: lead of the ball screw assembly. and the effective thread length of the ball screw assembly ; S3. Decompose the relative rotation number of the screw and nut into integer parts. and decimal part : ； In the formula, Indicates the rounding operation; This leads to the circumferential rotational deviation. ; S4. Calculate the total phase angle of the second protrusion relative to the starting edge of the screw thread. : ； S5. Calculate the angle of the first protrusion in intervals. : ； S6, according to angle and angle The first protrusion and the second protrusion are integrally machined on the rotor and the nut, respectively.

2. The working method of the anti-jamming pressure building unit as described in claim 1, characterized in that: This includes pressure build-up and return stroke. During pressure build-up, the motor drives the rotor to rotate in the forward direction, which in turn drives the screw to rotate. At this time, under the action of the screw and nut, the nut moves along the screw axis, thereby driving the PSU piston to extend and compress the brake fluid to build up pressure. During the return stroke, the motor drives the rotor to rotate in the opposite direction, which in turn drives the screw to rotate in the opposite direction, thereby causing the nut and PSU piston to move in the opposite direction, releasing the braking pressure until the first protrusion on the nut and the second protrusion on the rotor make rigid contact, preventing the nut from moving further. At this time, there is a safe gap between the first protrusion and the rotor and between the second protrusion and the nut, waiting for the next pressure build-up.

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