CN107314905A - A kind of automotive electronics brakes simulation executing - Google Patents

Abstract

A kind of automobile electronic braking system analog actuator, it is characterized in that, described analog actuator comprises the brake disc (18) that is connected with power take-off shaft rotation and a movable supporting platform (26), and described brake disc ( 18) The inner and outer brake blocks (25) and outer brake blocks (30) are respectively arranged on the inner and outer sides, and the inner brake blocks (25) and the outer brake blocks (30) can slide reciprocatingly along the axis of the rotating disc, The outer brake block (30) is connected to the supporting platform (26) through the connecting rod assembly (9), and the movable supporting platform (26) can reciprocate along the axial direction of the brake disc (18). A thrust mechanism is provided on the movable support platform (26), and the thrust mechanism is used to push the inner brake block (25) to approach the brake disc.

Description

An analog actuator for automotive electronic braking system

technical field

The invention belongs to a simulation experiment equipment, in particular to a simulation actuator of an automobile electromechanical braking system.

Background technique

With the rapid development of automobile intelligence, automobile wire control technology has emerged at the historic moment, and has been widely used in the whole vehicle. It is a new control system based on information interaction system and real-time control. As a branch of automotive wire control technology, the automotive electromechanical braking system is used to replace the traditional hydraulic and pneumatic braking systems. Its structural principle and control algorithm are very different from the traditional braking system. It is a new car brake concept. The automotive electromechanical braking system has been extensively studied in foreign auto companies due to its advantages of energy saving, environmental protection and fast braking response. Its theoretical research, test platform and prototype manufacturing started relatively late in China, but after recent years There have also been considerable breakthroughs in development. With the rapid development of highways and the continuous increase of vehicle speed, modern vehicles require higher comfort, safety and stability, which also puts forward higher requirements for automotive electromechanical brake control technology.

The automotive electromechanical braking system is a new type of braking method. The basic structure of the traditional braking system test bench is inconsistent with it, and the function is single, which can no longer meet the requirements of use. Based on the dynamic system, it fully demonstrates the composition structure and working process of the automotive electromechanical braking system, and facilitates the measurement of the braking force and response efficiency of the electromechanical braking system.

Contents of the invention

The purpose of the present invention is to provide a simulation actuator for the electronic braking system of an automobile, so as to overcome the deficiencies in the prior art.

In order to solve the above technical problems, the present invention provides the following technical solutions:

A simulated actuator for an automotive electronic braking system, the structural feature of which is that the simulated actuator includes a brake disc that is rotatably connected to a power output shaft and a movable support platform, and inner and outer sides of the brake disc are respectively set. The brake block and the outer brake block, the inner brake block and the outer brake block can reciprocate and slide along the axial direction of the rotating brake disc, the outer brake block is connected with the support platform through the connecting rod assembly, and the movable The movable support platform can reciprocate along the axial direction of the brake disc, and a thrust mechanism is provided on the movable support platform, and the thrust mechanism is used to push the inner brake block closer to the brake disc.

Further, the thrust mechanism includes a torque motor fixed on the movable support platform, the output shaft of the torque motor is connected to the input shaft of the reducer, and the output shaft of the reducer is connected to the ball screw pair through a flexible coupling. The ball screw is connected, and the ball screw auxiliary nut is fixedly connected with the pressure plate facing the inner brake block; the support platform can reciprocate along the ball screw auxiliary axis on the test bench.

Further, a caliper body is provided above the brake disc, and the caliper body includes a pair of sliding beams parallel to the brake disc axis, and the inner brake block and the outer brake block are respectively provided with lifting lugs, and the The lifting lug is slidingly lapped on the sliding beam of the caliper body.

Further, the connecting rod assembly includes a fixed seat fixed to the movable support platform and an "L"-shaped clearance fit body, and the vertical plate of the clearance fit body is embedded between the outer brake block and the side beam of the caliper body for dialing Move the outer brake pads.

Further, counterweight holes are evenly arranged on the brake disc, and brake disc counterweights detachably connected to the counterweight holes are provided to realize braking by changing the number of brake disc counterweights on the brake disc. Changes in the inertial mass of the disk.

Further, the brake disc counterweight is embedded and fixed in the counterweight hole of the brake disc through screws.

Compared with prior art, the beneficial effect of the present invention is:

The invention simulates the brakes of automobiles through the analog actuator of the electronic braking system, can truly simulate the working process of the electronic mechanical braking system of the automobile, has simple structure, low manufacturing cost and is easy to implement, has good versatility, and is convenient for measuring electronic mechanical braking. System brake pressure and its brake gap elimination time test test.

Description of drawings

Fig. 1 and Fig. 2 are structural schematic diagrams of the automobile electromechanical braking system of the present invention.

Fig. 3 is a schematic diagram of the partial structure of the caliper body and the brake block of the present invention.

Fig. 4 is a structural schematic diagram of the brake block of the present invention.

Fig. 5 is a schematic diagram of the structure of the moving link assembly of the present invention.

Fig. 6 is a schematic structural diagram of the test bench for the automotive electromechanical braking system applied in the present invention.

Fig. 7 is a schematic diagram of the structure of the pedal simulator in the test bench of the automotive electromechanical braking system.

Fig. 8 is a structural schematic diagram of the brake disc of the present invention.

Among them: 1. Universal wheel 2. Bench 3. Inverter 4. Three-phase asynchronous motor 5. Electromagnetic clutch 6. Bearing seat 7. Mass block 8. Side beam 9. Connecting rod assembly 10. Coupling 11. Planet Gear reducer 12. Permanent magnet DC brushless torque motor 13. Slider 14. Guide rail 15. Digital display 16. Control system 17. Analog control power supply 18. Brake disc 19. Ball screw 20. Support seat 1 21. Lead screw nut 22. Pressure plate 23. Support seat two cover 24. Support seat two 25. Inner brake block 26. Support platform 27. Brake disc counterweight 28. Brake disc counterweight positioning screw 29. Caliper body 30. Outer brake block 31. Lifting lug 32. Support seat-fixed seat 33. Connecting rod 34. Clearance fit body 35. Fixed component 36. Displacement sensor 40. Brake pedal 41. Brake connecting rod 42. Return spring 43. Spring buckle 44. Pedal rotation axis 45. Rotating arm 46. Rocker arm 47. Driving arm 48. Travel sensor

detailed description

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

As shown in Figure 6, it is the automotive electromechanical braking system test bench applied in the present invention, comprising a test bench stand 2, which is provided with an electromechanical braking system actuator module, a simulated automobile driving module, The brake signal acquisition module and the pedal simulator module, the universal wheel 1 is provided at the bottom of the test bench, and the caster self-locking device is arranged on the universal wheel.

Wherein, the actuator module of the electronic mechanical braking system of the present invention, referring to Fig. 1 and Fig. 2, includes an inner brake block 25 arranged on the outside of the brake disc 18, a permanent magnet DC brushless torque motor 12, a planetary gear reducer 11, Ball screw 19, screw nut 21, pressure plate 22.

A caliper body 29 is provided above the brake disc 18, and the caliper body 29 includes a pair of sliding beams parallel to the axial direction of the brake disc. The inner brake block 25 and the outer brake block 30 are respectively provided with lifting lugs 31, and the lifting lugs 31 slide Overlap on the sliding beam of the pliers body 29.

The permanent magnet DC brushless torque motor 12 is driven by the output control voltage of the pedal simulator, the output shaft of the permanent magnet DC brushless torque motor 12 is connected to the input shaft of the planetary gear reducer 11, and the output shaft of the planetary gear reducer 11 is connected to the ball screw pair , wherein the ball screw pair includes a ball screw 19, a ball screw nut 21, the ball screw nut 21 is fixedly connected with the pressure plate 22, and the pressure plate 22 contacts and brakes with the inner brake block 25 during braking. The permanent magnet DC brushless torque motor 12, the planetary gear reducer 11 and the ball screw pair are supported by the support seat 1 20 and the support seat 2 24, and are fixed on the support platform 26, and the whole support platform 26 is fixed on the fixed assembly 35, and fixed The bottom of the assembly 35 is provided with a slide block 13, and the test bench frame 2 is provided with a slide rail 14 slidingly matched with the slide block 13, and the support platform 26 can move horizontally on the test bench frame 2 along the slide rail, and the horizontal movement direction Consistent with the axial direction of the brake disc.

The pedal simulator outputs the control voltage drive, that is, the original voltage output by the travel sensor 48 of the aforementioned pedal simulator, which is processed by the control system to control the motor drive.

Referring to Fig. 1, Fig. 2, Fig. 5, the connecting rod assembly 9 includes a fixed seat 32, a connecting rod 33 and a clearance fit body 34, the fixed seat 32 is fixedly connected to the supporting seat 1 20 by bolts, and the supporting seat 2 includes a detachably installed The second body 24 of the support seat and the second cover 23 of the support seat form a limit hole between the second body 24 of the support seat and the second cover 23 of the support seat; the connecting rod 33 of the connecting rod assembly runs through the limit hole, and the clearance fit body 34 is L-shaped structure, its riser is embedded in the gap between the side beam 8 of the caliper body 29 and the outer brake block 30 .

During linkage, the actuator module drives the support seat 20 to move to the right, drives the connecting rod assembly to move through the support seat 1 fixed seat 32, and drives the outer brake block 30 to move to realize the contact between the outer brake block and the brake disc 18.

Referring to Fig. 6, Fig. 8, the simulated vehicle running module in the test stand comprises three-phase asynchronous motor 4, electromagnetic clutch 5 and the brake disc 18 that is attached to the brake disc weight 27, the brake disc counter weight 27 and the brake disc. The disc 18 is fixed by the positioning screw 28 of the brake disc counterweight. The change of the number of the brake disc counterweight 27 realizes the change of the inertial mass of the brake disc. The analog control power supply 17 can be adjusted in real time by the control system 16 of the three-phase asynchronous motor 4. Control voltage to simulate changes in wheel speed. The brake disc 18 is connected with the frequency converter 3 for speed regulation through the input end of the three-phase asynchronous motor 4, the output shaft is connected with the electromagnetic end of the electromagnetic clutch 5 through a connecting key, and the three-phase asynchronous motor 4 and the brake disc 18 are connected through two ends. The bearing with the bearing seat 6 is supported on the test bench, and the flange end of the electromagnetic clutch 5 is connected with the center shaft of the brake disc through a connection key.

In order to accurately simulate the state of the car at any speed, a 1.5KW-220AC frequency converter 3 is installed for the three-phase asynchronous motor, and the relationship between the frequency value of the frequency converter and the wheel speed adjusted by the control system 16 is as follows:

In the formula (1), n is the motor speed, rev/min, f is the frequency, s is the slip rate, generally 0.01-0.02; p is the number of electromagnetic pole pairs of the motor, p is 1 for a two-pole motor, and 1 for a four-pole motor 2, take 2 here.

The frequency f is 50Hz under normal conditions, simulating the normal wheel speed, and the frequency value can be adjusted according to the requirements of the test object to realize the change of the wheel speed.

Referring to Fig. 1, Fig. 2, Fig. 6, the brake signal acquisition module in the test bench includes digital display 15, displacement sensor 36 (KSC-8mm displacement sensor) and pressure sensor, and displacement sensor 36 is symmetrically installed in inner brake block 25 and Between the brake block lugs 31 of the outer brake block 30, the displacement sensing terminal is close to the back plate of the inner brake block 25, and the bottom terminal is close to the outer brake block 30; the limit beam 8 and the pressure plate 22 act together on the inner The brake block 25 and the outer brake block 30 ensure that the displacement sensor 36 is pre-tightened horizontally, and the spring of the displacement sensor 36 acts on the four brake block lugs 31 to ensure that the brake returns to its original position. The digital display can simultaneously display the same Changes in pressure and displacement values over time.

There is a threaded hole on the side of the pressure sensor, which is fixed on the corresponding pressure sensor fixing plate through threaded connection. The structure of the fixing plate is equal to the inner brake block 25, and has the function of friction braking. The fixing plate is hung on the caliper body, but the thickness is small , During the experiment, instead of the inner brake block 25 being arranged on the inner side of the brake disc 18, the induction pressure head is close to the outer side of the fixed plate, and the digital display can simultaneously display the pressure and displacement numerical changes at the same time.

Referring to FIG. 7 , the pedal simulator is mainly composed of a transmission part and a sensing part, and converts the angle change of the brake pedal 40 around the pedal rotation axis 44 into the voltage change of the travel sensor 48 . The transmission part includes a brake pedal 40 , a brake connecting rod 41 , a return spring 42 , a spring buckle 43 and a pedal rotation axis 44 . The brake pedal 40 and the brake connecting rod 41 are fixedly connected to receive the pedal braking force; the return spring 42 and the brake connecting rod 41 are connected through a spring buckle 43 to support the brake connecting rod 41 and provide braking reaction force; The rotation axis 44 is arranged on the base platform, and the brake connecting rod 41 is rotatably connected with the pedal rotation axis 44 and can move within a certain angle around the pedal rotation axis 44 .

The sensing part includes a rotary arm 45 , a rocker arm 46 , a driving arm 47 and a stroke sensor 48 . The pivoting arm is fixedly connected to the rotation axis of the pedal. The pivoting arm 45, the rocking arm 46 and the driving arm 47 are sequentially connected by hinges, and the driving arm is connected to the stroke sensor; the other end of the stroke sensor is fixed on the base platform, and the stroke sensor 48 adopts the principle of a resistance sensor. The resistance value is changed by driving the driving arm 47 . In the experiment, the brake pedal 40 changes proportionally around the angle of the pedal rotation axis 44, and the voltage of the stroke sensor 48 is calculated as follows:

The relationship between the output voltage of the pedal simulator and the pedal angle is expressed by the following formula:

In formula (2), for the output voltage of the travel sensor 48, θ is the angle between the initial position of the rotating arm (45) and the vertical direction, a is the length of the rotating arm (45), U ₀ is the input voltage of the travel sensor (48) , L is the resistance total length of travel sensor (48), is the angle of rotation of brake pedal (40).

The working principle of the inventive scheme is as follows:

During the experiment, move the fixed assembly 35 to the limit position, the distance between the pressure plate 22 and the inner brake block is about 0.1mm, turn on the power supply of the electromagnetic clutch 5, and the electromagnetic clutch 5 is closed, so that the brake disc 18 is at the design speed and design load. Running, adjusting the output frequency of the frequency converter 3, changing the speed of the three-phase asynchronous motor 4, simulating the driving speed of the wheels under test conditions, changing the number of mass blocks 27 on the brake disc 18, realizing variable moment of inertia, simulating design load changes, digital display 15 Displays the rotational speed of individual wheels in real time.

By replacing the brake torque motor 12 and the speed reducer 11 of the actuator, the parameter change of the torque of the continuous stall of the actuator and the transmission ratio can be realized, and the change of the brake type of a small car and a mini SUV can be simulated. When the model of the torque motor 12 is J110LYX04A permanent magnet brushless DC motor, the model of the reducer 11 is NGW planetary gear reduction mechanism and the transmission ratio is 4.3, the simulation is a small car, and the torque of continuous stalling at this time is 3.2N.m , the transmission ratio is 4.3; when the continuous locked-rotor torque of the torque motor 12 is greater than 3.2N.m, and the transmission ratio is 4.3-7.9, the simulated mini SUV model.

During braking, the electromagnetic clutch 5 is disconnected, and the power connection between the brake disc 18 and the three-phase asynchronous motor 4 is cut off. The pedal simulator converts the angle change of the brake pedal 40 around the pedal rotation axis 44 into the voltage change of the travel sensor 48, and the voltage and angle change as shown in formula (2).

In the present embodiment: θ is 30°, a length is 3cm, U ₀ is 12V, and the resistance total length L of stroke sensor is 12cm, Measured with an angle ruler.

According to the variation of the pedal rotation angle, the stroke sensor 48 outputs a variable voltage to the control system 16, and the control system 16 outputs a control voltage to drive the permanent magnet DC brushless torque motor, and the permanent magnet DC brushless torque motor 12 is variable The variable torque is output under voltage. After the planetary gear reducer 11 decelerates and increases the torque, the ball screw pair acts as a motion conversion device to convert the high torque transmitted by the planetary gear reducer 11 into the variable axial thrust of the screw nut 21. Push the inner brake block 25 to move towards the brake disc 18. When the inner brake block 25 contacts the brake disc 18 to generate a contact force, the contact force acts on the ball screw pair to generate a reaction force. The permanent magnet DC brushless torque motor 12. The planetary gear reducer 11 and the ball screw pair are installed on the support platform 26, and the support platform 26 moves along the guide rail 14 to the direction away from the brake disc 18 under the reaction force. connection, the clearance fit body of the brake linkage assembly drives the outer brake block 30 to move toward the brake disc 18, and when both the inner brake block 25 and the outer brake block 30 are in contact with the brake disc 18, a variable Brake pressure until braking is complete.

The digital display 15 monitors the output voltage of the pedal in real time, the change of the pedal rotation angle, the brake pressure value, the change value of the displacement sensor and its time information, and calculates the brake clamping force and the brake gap elimination time based on this, and compares and reflects it with the brake regulations The braking effect of the brake actuator.

Further provide the system test bench test method of the present invention and test result analysis below

(1) Test method

The three-phase asynchronous AC motor 4 drives the automobile brake disc 18 with counterweight 27 to run to simulate the actual driving process of the vehicle. The three-phase asynchronous AC motor 4 is connected to the automobile brake disc 18 through the electromagnetic clutch 5, and the electromagnetic clutch 5. The on-off control of the current realizes the connection and disconnection of the three-phase asynchronous AC motor 4 and the brake disc 18 of the automobile. The torque motor 12 is controlled by changing the angle of the brake pedal 40 of the pedal simulator, and the relationship between its output voltage and the angle of the brake pedal 40 is shown in formula (2). The digital display shows the voltage value output by the brake pedal simulator, the pressure sensor and the displacement sensor value in real time,

(2) Brake pressure test test

During the test, the support platform is fixed on the guide rail 14, so the system actuator and the test bench support do not slide relative to each other. During braking, the pressure plate 22 acts directly on the pressure head of the pressure sensor.

Control the 40° angle of the brake pedal respectively, apply voltage values of 2V, 4V, 6V, 8V, 10V and 12V to the torque motor, and record the values displayed by the pressure sensor, as shown in Table 1.

Table 1 Comparison of the experimental value of the brake clamping force with the theoretical value and simulation value

The experimental value of the brake clamping force is not much different from the theoretical value and the simulated value, which shows that the experimental design fully meets the requirements of the braking force test. Under the three conditions, the brake clamping force increases with the increase of the locked-rotor voltage, which is approximately proportional to the change, which is also the advantage of the electronic mechanical brake system to adjust the braking force by adjusting the voltage. The experimental value is slightly smaller, which is mainly affected by factors such as the installation error during the test, the mechanical characteristics of the motor itself, and the complex external environmental conditions.

The theoretical values in Table 1 are calculated according to the structure of the torque motor, reducer and screw nut shown in Figure 2 through mechanical knowledge; the simulated values are obtained through ADAMS simulation modeling analysis.

(3) Brake gap elimination time test test

The system actuator module is divided into two processes in the phase of eliminating the brake gap, from the start of the motor to the maximum no-load speed and the constant speed of the motor. Since the time to eliminate the braking gap is very short, the gap between the brake block and the brake disc on one side of the car is 0.1mm, and the total braking gap is 0.2mm. It is difficult to accurately set 0.1mm on both sides of the brake disc, so set the original If the gap is 2.5mm, the inner and outer gaps are 5mm in total.

The test steps are as follows:

1) Install and fix the torque motor 12 and the reducer 11 according to the braking requirements of the small car;

2) Fix the slider 13 on the guide rail 14 to ensure that the actuator and the test bench support can slide relatively;

3) Arrange two displacement sensors 36 between the inner brake block 25 and the outer brake block 30, replace the inner brake block 25 with the pressure sensor fixing plate installed with the pressure sensor, and hang it on the inlay 29 through its lifting lug, Install and fix the connecting rod assembly 9;

4) Increase or decrease the brake disc counterweight 27 in the brake disc 18 according to the requirements of the test working conditions;

5) Turn on the power supply, adjust the frequency converter 3, control the rotation of the motor 4, connect the power supply of the electromagnetic clutch 5, the electromagnetic clutch 5 is closed, and drive the brake disc 18 to rotate;

6) Change the angle of the pedal simulator pedal 40, and the torque motor 12 will drive and work to realize braking. Observe the stroke sensor 48 output voltage value on the digital display instrument, when the voltage value is 2V, 4V, 6V, 8V, 10V and 12V, measure the angle change of the pedal 40 with an angle ruler, read the output value of the pressure sensor, and record it in the table 1 in;

7) Observe the stroke sensor 48 output voltage value on the digital display instrument, the displacement variation of the displacement sensor 36 and the time variation of the brake block, when the pressure plate 22 contacts the pressure sensor, start to record the time; when the displacement sensor 36 is displayed as 2mm, For 3mm, 4mm and 5mm, record the time in Table 2, and calculate the running speed of the brake block according to the time-displacement formula, and record it in Table 2.

8) Cut off the power supply and the test is over.

Table 2 Displacement sensor measurement data

According to the above experimental results, it can be concluded that the maximum speed of the brake block running at a constant speed in the stage of eliminating the brake gap is 2.53mm/s, which meets the use requirement of 2mm/s in the braking regulations. According to the inspection report provided by the torque motor manufacturer, the response time of this type of torque motor to the maximum no-load speed is 0.04s, and the moving distance of the brake block during this response time period is about 0.05mm. The dynamic gap time is about 0.10s, which meets the use requirements of the brake regulation gap elimination time of 0.05-0.15s.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (6)

1. a kind of automotive electronics brakes simulation executing, it is characterised in that the simulation executing includes and power output Axle is rotated to be set respectively inside and outside the brake disc (18) connected and a removable support platform (26), the brake disc (18) Inside brake block (25), outer brake block (30) are put, the inside brake block (25) and outer brake block (30) can be along transformation of ownership Moving plate axial directions Reciprocatingly slide, the outer brake block (30) is connected by link assembly (9) with support platform (26), the removable support platform (26) it can axially be moved reciprocatingly along brake disc (18), thrust mechanism is provided with the removable support platform (26), it is described Thrust mechanism is used to promote inside brake block (25) close to brake disc.

2. a kind of automotive electronics brakes simulation executing according to claim 1, it is characterised in that the thrust machine Structure includes the torque motor (12) being fixed in removable support platform (26), the output shaft of the torque motor (12) and deceleration Device (11) input shaft is connected, and decelerator (11) output shaft passes through flexible coupling (10) and the ball-screw of ball screw assembly, (19) connect, rolling ball screw pair screw nut (21) is fixedly connected with being right against the platen (22) of inside brake block (25)；The support is flat Platform (26) can be moved on experimental stand (2) along ball screw assembly, axial reciprocating.

3. a kind of automotive electronics brakes simulation executing according to claim 1, it is characterised in that the brake disc (18) top is provided with caliper (29), and the caliper (29) includes a pair and the axially in parallel skid beam of brake disc, the inside brake block (25) and outer brake block (30) is respectively equipped with hanger (31), the hanger (31) is slided and is overlapped in the skid beam of caliper (29).

4. a kind of automotive electronics brakes simulation executing according to claim 3, it is characterised in that the connection rod set Part (9) includes fixed seat (32) and " L " the shape gap ligand (34) fixed with removable support platform (26), and the gap is matched somebody with somebody Fit vertical plate is embedded between outer brake block (30) and caliper (29) side bar, for stirring outer brake block (30).

5. a kind of automotive electronics brakes simulation executing according to claim 1, it is characterised in that the brake disc (18) balancing weight hole has been evenly arranged on, the brake disc balancing weight (27) being detachably connected with balancing weight hole is set, has passed through braking The change of brake disc inertia mass is realized in the change of brake disc balancing weight (27) quantity on disk (18).

6. a kind of automotive electronics brakes simulation executing according to claim 1, it is characterised in that the brake disc is matched somebody with somebody Pouring weight (27) is fixed in the balancing weight hole of brake disc (18) by the way that screw is embedded.