A test tool for EMB transmission system efficiency

Abstract

The utility model relates to a kind of test tool of EMB transmission system efficiency, input motor is fixed on input motor mounting plate left side;Input torque sensor is installed between input motor mounting plate and first bearing seat;Input gear shaft, gear transmission system are sequentially connected between first bearing seat and gear transmission system mounting plate;Output gear shaft is installed between gear transmission system mounting plate and second bearing seat;Output torque sensor is installed between second bearing seat and third bearing seat;Ball screw input spline is connected between third bearing seat and ball screw system mounting plate;Ball screw system is connected on ball screw system mounting plate right side, and the both sides of ball screw system are respectively connected ball screw input spline and force sensor.A kind of test tool of EMB transmission system efficiency designed using the utility model, can solve the order of magnitude of input end torque and output end clamping force, the difference of range, make the arrangement of test tool and the selection of sensor become complex problem.

Description

Technical Field

[0001] This utility model relates to the field of vehicle braking test technology, specifically to a test fixture for the efficiency of an EMB transmission system. Background Technology

[0002] As braking systems in passenger and commercial vehicles evolve towards brake-by-wire, EMB systems convert motor torque into brake caliper clamping force through a motor, gear reduction system, and ball screw system. Compared to traditional hydraulic brakes, EMB has a longer drive chain and a more precise transmission structure. The transmission efficiency of the gear reduction system and ball screw system directly affects braking response, energy consumption, and thermal management performance.

[0003] In the actual development and calibration process, it is necessary to quantify the efficiency of the EMB drive system in order to evaluate the impact of different gear transmission schemes, different ball screw parameters, and different lubrication and preload methods on system performance. However, EMB drive systems typically have a large overall transmission ratio. The motor output torque is amplified by multiple stages of gear transmission and then converted into a large linear clamping force through the ball screw. This results in a significant difference in the magnitude and range between the input torque and the output clamping force, complicating the arrangement of test fixtures and the selection of sensors.

[0004] Therefore, existing technologies have shortcomings and need to be improved and developed. Utility Model Content

[0005] The utility model provides a test fixture for the efficiency of an EMB drive system, which solves the problem that EMB drive systems typically have a large overall transmission ratio, and the motor output torque is amplified by multi-stage gear transmission and then converted into a large linear clamping force through a ball screw. This results in a large difference in the magnitude and range between the input torque and the output clamping force, making the arrangement of the test fixture and the selection of sensors complicated.

[0006] This utility model embodiment provides a testing fixture for the efficiency of an EMB transmission system, comprising, from left to right, an input motor mounting plate, a first bearing housing, a gear transmission system mounting plate, a second bearing housing, a third bearing housing, and a ball screw system mounting plate; an input motor is fixed to the left side of the input motor mounting plate; an input torque sensor is installed between the input motor mounting plate and the first bearing housing, and the two sides of the input torque sensor are respectively connected to the input motor and the first bearing housing via a first coupling; an input gear shaft and a gear transmission system are sequentially connected between the first bearing housing and the gear transmission system mounting plate; the... An output gear shaft is installed between the gear transmission system mounting plate and the second bearing housing, with both ends of the output gear shaft connected to the gear transmission system and the second bearing housing, respectively. An output torque sensor is installed between the second bearing housing and the third bearing housing, with both sides of the output torque sensor connected to the second bearing housing and the third bearing housing, respectively, via a second coupling. A ball screw input spline is connected between the third bearing housing and the ball screw system mounting plate. A ball screw system is connected to the right side of the ball screw system mounting plate, with the ball screw input spline and a force sensor connected to both sides of the ball screw system, respectively.

[0007] Furthermore, a pad is placed below the force sensor to align the center of the force sensor with the center of the piston of the ball screw system.

[0008] Furthermore, it also includes a base plate, on which the input motor mounting plate, the first bearing seat, the gear transmission system mounting plate, the second bearing seat, the third bearing seat, and the ball screw system mounting plate are all fixed and arranged sequentially along a straight line so that the center lines of each shaft system are collinear.

[0009] Furthermore, rolling bearings are respectively provided inside the first bearing housing, the second bearing housing, and the third bearing housing, and the input gear shaft, the output gear shaft, and the ball screw input spline are respectively supported in the corresponding bearing housing by the corresponding rolling bearings.

[0010] Furthermore, the first coupling and the second coupling are flexible couplings.

[0011] Furthermore, the ball screw system includes a ball screw fixedly connected to the ball screw input spline, a ball nut threadedly engaged with the ball screw, and a piston fixedly connected to the ball nut and passing through the brake caliper cylinder. The end of the piston along the clamping direction abuts against the force measuring surface of the force sensor.

[0012] Furthermore, the force sensor is arranged between the two clamping surfaces of the brake caliper, and the brake caliper is fixedly mounted on the ball screw mounting plate so that the force sensor is aligned with the axis of the ball screw.

[0013] Beneficial effects:

[0014] As can be seen from the above technical solutions, this utility model provides a testing fixture for the efficiency of an EMB transmission system, which has the following beneficial effects:

[0015] 1. This application enables segmented testing of the efficiency of gear transmission systems and ball screw transmission systems: By placing an input torque sensor between the motor and the gear transmission system in the transmission link, an output torque sensor between the gear transmission system and the ball screw system, and a clamping force sensor at the output end of the ball screw system, the input torque of the gear transmission system, the output torque of the gear transmission system, and the clamping force measured by the force sensor can be obtained separately. Combined with the known gear ratio and ball screw lead, the efficiency of each transmission stage and the overall efficiency can be calculated. Compared with test schemes that only obtain the overall efficiency, this structure facilitates separate performance diagnosis and optimization of the gear transmission system and the ball screw transmission system.

[0016] 2. Improve the consistency and accuracy of the mechanical boundaries of test results: This application uses the linear arrangement of the base plate, each mounting plate and bearing seat, and the rolling bearing support structure to make the center lines of the shaft system collinear. With the help of the flexible coupling to compensate for installation errors, it reduces the additional friction and torque fluctuations caused by assembly errors. By aligning the force sensor with the piston center and arranging it in the caliper clamping space, the line of action of the clamping force is aligned with the sensor axis, reducing off-center load and improving the reliability of the measurement results.

[0017] 3. Maintain consistency between the tooling structure and the actual EMB structure: This application introduces a brake caliper cylinder and piston structure into the test tooling, so that the output end of the ball screw system is similar to the structure in the actual EMB. This allows the influence of factors such as lubrication and guidance inside the ball screw and caliper on efficiency during the test to be truly reflected, which is beneficial for using the test results in the development of the actual vehicle.

[0018] 4. Facilitates adaptation to different prototypes and engineering applications: Through the adjustable mounting structure on the base plate and the adjustable position design of the ball screw mounting plate and force sensor, this application can adapt to EMB prototypes with different caliper widths and different ball screw strokes; through the data acquisition module and display unit, multiple test data can be easily recorded and compared in a centralized manner, making it suitable for promotion and application in enterprise development laboratories.

[0019] 5. Reduce sensor selection and assembly risks: By introducing an intermediate torque measurement position in the transmission system and applying an axial alignment structure to the force sensor, this application can select torque and force sensors within a reasonable range, avoiding sensor damage or reduced lifespan due to excessive load or eccentricity, while reducing measurement errors and improving the reliability of the testing system.

[0020] It should be understood that all combinations of the foregoing concepts and the additional concepts described in more detail below can be considered part of the inventive subject matter of this disclosure, provided that such concepts do not contradict each other.

[0021] The foregoing and other aspects, embodiments, and features of the teachings of the present invention will be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the invention, such as features and / or beneficial effects of exemplary embodiments, will become apparent from the following description or may be learned through practice of specific embodiments according to the teachings of the present invention. Attached Figure Description

[0022] The accompanying drawings are not drawn to scale. In the drawings, each identical or nearly identical component shown in the various figures may be denoted by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the invention will now be described by way of example and with reference to the accompanying drawings, wherein:

[0023] Figure 1 This is a schematic diagram of the structure of a test fixture for the efficiency of an EMB transmission system in an embodiment of this application.

[0024] Explanation of icon numbers:

[0025] 1. Output gear shaft; 2. Gear transmission system; 3. Input torque sensor; 4. Input motor; 5. Input gear shaft; 6. Output torque sensor; 7. Ball screw input spline; 8. Force sensor; 9. Input motor mounting plate; 10. Ball screw system; 11. First coupling; 12. First bearing housing; 13. Gear transmission system mounting plate; 14. Second bearing housing; 15. Second coupling; 16. Third bearing housing; 17. Ball screw system mounting plate. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this invention pertains.

[0027] The terms "first," "second," and similar words used in the specification and claims of this patent application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, unless the context clearly indicates otherwise, the singular forms of "an," "a," or "the," etc., do not indicate a quantity limitation, but rather indicate the presence of at least one. Terms such as "comprising" or "including" indicate that the element or object preceding "comprising" encompasses the features, integrals, steps, operations, elements, and / or components listed following "comprising" or "including," and do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or sets thereof. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; these relative positional relationships may change accordingly when the absolute position of the described object changes.

[0028] In the actual development and calibration process, it is necessary to quantify the efficiency of the EMB drive system in order to evaluate the impact of different gear transmission schemes, different ball screw parameters, and different lubrication and preload methods on system performance. However, EMB drive systems typically have a large overall transmission ratio. The motor output torque is amplified by multiple stages of gear transmission and then converted into a large linear clamping force through the ball screw. This results in a significant difference in the magnitude and range between the input torque and the output clamping force, complicating the arrangement of test fixtures and the selection of sensors.

[0029] Therefore, this utility model embodiment provides a testing fixture for the efficiency of an EMB transmission system, referring to... Figure 1 It includes, from left to right, an input motor mounting plate 9, a first bearing housing 12, a gear transmission system mounting plate 13, a second bearing housing 14, a third bearing housing 16, and a ball screw system mounting plate 17, which are fixed in sequence.

[0030] An input motor 4 is fixed to the left side of the input motor mounting plate 9;

[0031] An input torque sensor 3 is installed between the input motor mounting plate 9 and the first bearing housing 12. The two sides of the input torque sensor 3 are connected to the input motor 4 and the first bearing housing 12 respectively through the first coupling 11.

[0032] The first bearing housing 12 and the gear transmission system mounting plate 13 are connected in sequence to the input gear shaft 5 and the gear transmission system 2.

[0033] An output gear shaft 1 is installed between the gear transmission system mounting plate 13 and the second bearing seat 14. The two ends of the output gear shaft 1 are respectively connected to the gear transmission system 2 and the second bearing seat 14.

[0034] An output torque sensor 6 is installed between the second bearing housing 14 and the third bearing housing 16. The two sides of the output torque sensor 6 are connected to the second bearing housing 14 and the third bearing housing 16 respectively through the second coupling 15.

[0035] A ball screw input spline 7 is connected between the third bearing housing 16 and the ball screw system mounting plate 17.

[0036] A ball screw system 10 is connected to the right side of the ball screw system mounting plate 17. The ball screw system 10 is connected to the ball screw input spline 7 and the force sensor 8 on both sides.

[0037] By sequentially arranging the input motor mounting plate 9, bearing seats at each stage, gear transmission system mounting plate 13, and ball screw system mounting plate 17 from left to right, a structure is formed along a transmission chain, ensuring that the input motor 4, gear transmission system 2, ball screw system 10, and caliper are subjected to consistent force directions. The input torque sensor 3 is positioned between the input motor 4 and the first bearing seat 12 to directly measure the input torque of the gear transmission system 2; the output torque sensor 6 is positioned between the gear transmission system 2 and the ball screw system 10 to directly measure the output torque of the gear transmission system 2 (which is also the input torque of the ball screw system 10); a force sensor 8 is connected to the right side of the ball screw system 10 to directly measure the clamping force. Through this structure, the input and output parameters of the gear transmission system 2 and the ball screw system 10 can be obtained simultaneously on the same frame, providing a basis for segmented calculation of efficiency and overall efficiency.

[0038] In some embodiments, a pad is placed below the force sensor 8 to align the center of the force sensor 8 with the center of the piston of the ball screw system 10.

[0039] By placing a pad under the force sensor 8, the center of the force sensor 8 is made to be flush with the center of the ball screw piston, which reduces the eccentric load and bending moment borne by the force sensor 8, so that the force sensor 8 mainly bears the axial clamping force, improves the stability and repeatability of the clamping force measurement results, and reduces the additional influence of the structure on the sensor.

[0040] In some embodiments, a base plate is also included. The input motor mounting plate 9, the first bearing seat 12, the gear transmission system mounting plate 13, the second bearing seat 14, the third bearing seat 16, and the ball screw system mounting plate 17 are all fixed on the base plate and arranged sequentially along a straight line so that the center lines of each shaft system are collinear.

[0041] By fixing the input motor mounting plate 9, each bearing seat, gear transmission system mounting plate 13, and ball screw system mounting plate 17 on the base plate and arranging them along a straight line, the center lines of each shaft system are collinear, which helps to improve the coaxiality of the entire transmission chain, reduce additional friction loss and mechanical vibration, thereby improving the reliability of transmission efficiency measurement during the test.

[0042] In some embodiments, rolling bearings are respectively provided inside the first bearing housing 12, the second bearing housing 14 and the third bearing housing 16, and the input gear shaft 5, the output gear shaft 1 and the ball screw input spline 7 are respectively supported in the corresponding bearing housings by the corresponding rolling bearings.

[0043] By installing rolling bearings in the first, second, and third bearing housings 16, the input gear shaft 5, output gear shaft 1, and ball screw input spline 7 are provided with rotational support, so that each shaft has stable support and good rotational performance during operation, reducing radial and axial runout of the shaft system, reducing additional mechanical losses and interference with torque measurement.

[0044] In some embodiments, the first coupling 11 and the second coupling 15 are flexible couplings.

[0045] By using flexible couplings between the input torque sensor 3 and the input motor 4, and between the output torque sensor 6 and the second bearing housing 14, the small radial and angular deviations that are unavoidable during installation can be compensated, the influence of eccentricity and different shafts on the transmission chain can be reduced, the additional load and measurement error on the torque sensor can be reduced, and the torque signal can be made closer to the real transmission torque.

[0046] In some embodiments, the ball screw system 10 includes a ball screw fixedly connected to the ball screw input spline 7, a ball nut threadedly engaged with the ball screw, and a piston fixedly connected to the ball nut and passing through the brake caliper cylinder, wherein the end of the piston along the clamping direction abuts against the force measuring surface of the force sensor 8.

[0047] By clearly defining the ball screw system 10 as including a ball screw, a ball nut, and a piston passing through the brake caliper cylinder, and with the piston end in direct contact with the force sensor 8's measuring surface, the rotation of the ball screw is converted into a linear displacement of the piston via the ball nut, which is then directly applied to the force sensor 8. This structure clarifies the force transmission path of the ball screw system 10, and while maintaining similarity to the actual EMB structure, facilitates the use of clamping force measurements for analyzing the ball screw transmission efficiency.

[0048] In some embodiments, the force sensor 8 is arranged between the two clamping surfaces of the brake caliper, and the brake caliper is fixedly mounted on the ball screw mounting plate 17 so that the force sensor 8 is aligned with the axis of the ball screw.

[0049] By arranging the force sensor 8 between the two clamping surfaces of the brake caliper and fixing the brake caliper on the ball screw mounting plate 17, the clamping space and force boundary conditions in actual braking conditions can be simulated, making the force state during testing closer to the actual vehicle installation state, which is beneficial to obtaining test results with engineering reference value in the laboratory environment.

[0050] In one specific embodiment, the test fixture includes a base plate, which can be a steel plate or a cast iron part, and its surface is machined to form a planar reference. The input motor mounting plate 9, the first bearing housing 12, the gear transmission system mounting plate 13, the second bearing housing 14, the third bearing housing 16, and the ball screw system mounting plate 17 are sequentially fixed to the base plate by bolts, with the bottom surfaces of each mounting plate and bearing housing fitting against the base plate. The shaft holes on each mounting plate and bearing housing are arranged in a straight line with a certain reference line on the base plate as a reference, ensuring that the output shaft of the input motor 4, the input gear shaft 5, the output gear shaft 1, the ball screw input spline 7, and the ball screw axis remain substantially collinear.

[0051] The input motor 4 is fixed to the left side of the input motor mounting plate 9, with its output shaft extending to the right. The input torque sensor 3 is connected to the output shaft of the input motor 4 via a first coupling 11, and the other end of the input torque sensor 3 is connected to the input gear shaft 5 installed in the first bearing housing 12 via the first coupling 11. The input torque sensor 3 is a flange-type torque sensor, and its housing is connected to the base plate or mounting plate via a bracket to prevent the sensor body from rotating with the shaft. The first coupling 11 is preferably a flexible pin coupling or a flexible coupling with a perforated shape, used to compensate for minor coaxiality deviations between the input motor 4 and the torque sensor, and between the torque sensor and the input gear shaft 5, while transmitting torque.

[0052] The input gear shaft 5 is supported by rolling bearings within the first bearing housing 12. One end of the shaft is connected to the input torque sensor 3, and the other end is fitted with the input gear. The gear transmission system 2 can be a single-stage or multi-stage gear set, fixed on the gear transmission system mounting plate 13, and meshes with the input gear. The output gear shaft 1 passes through the gear transmission system mounting plate 13 and is supported by rolling bearings within the second bearing housing 14. The output gear is fixed on the output gear shaft 1 and meshes with a certain stage of gear in the gear transmission system 2, forming a predetermined transmission ratio i. The right end of the output gear shaft 1 is connected to the output torque sensor 6 via the second coupling 15. The other end of the output torque sensor 6 is connected to the ball screw input spline 7 supported within the third bearing housing 16 via the second coupling 15.

[0053] The third bearing housing 16 also houses a rolling bearing to support the ball screw input spline 7. One end of the spline is connected to the output torque sensor 6 via the second coupling 15, and the other end is fixedly connected to the ball screw. The ball screw and ball nut are threaded together and the ball nut is fixed to the brake caliper cylinder or its connecting parts. The piston passes through the brake caliper cylinder and is connected to the ball nut. When the ball screw rotates, it drives the ball nut to move relative to the ball screw, thereby pushing the piston to move in the clamping direction.

[0054] The brake caliper is fixed to the ball screw mounting plate 17, and the force sensor 8 is placed within the clamping space of the caliper. The piston end abuts against the force measuring surface of the force sensor 8, and the other side of the force sensor 8 is supported on the base plate or an independent support structure by a pad. The pad is a block-shaped component fixed to the base plate, and its thickness is determined according to the caliper mounting height and the mounting position of the ball screw system 10, ensuring that the center of the force sensor 8 is collinear with the center of the piston. The mounting holes of the ball screw mounting plate 17 and / or the force sensor 8 on the base plate are elongated holes, allowing for adjustable allowance along the ball screw axis to accommodate the width and stroke of calipers of different parts.

[0055] The working principle of a testing fixture for the efficiency of an EMB drive system is as follows:

[0056] 1. According to Figure 1 Perform the installation;

[0057] 2. The input motor 4 drives the gear transmission system 2 to rotate via the input gear shaft 5, and the input torque sensor 3 can measure the torque of the input gear transmission system 2. ;

[0058] 3. The gear transmission system 2 drives the output gear shaft 1 to rotate. The output gear shaft 1 and the ball screw input spline 7 are rigidly connected by the output torque sensor 6. The output gear shaft 1 drives the ball screw input spline 7 to rotate. The ball screw system 10 converts the rotational motion of the ball screw input spline 7 into the linear motion of the piston. The output torque sensor 6 can measure the output torque of the gear transmission system 2 (the input torque of the ball screw system 10). ;

[0059] 4. The piston of the ball screw system 10 moves forward, and the clamping force sensor 8 measures the clamping force. ;

[0060] Efficiency can be calculated using the following formula:

[0061] Efficiency of gear transmission system 2 , This is the transmission ratio of gear transmission system 2;

[0062] Efficiency of ball screw series 10 , This refers to the lead of the ball screw;

[0063] Overall efficiency .

[0064] Example: Set the input torque of input motor 4 to 1.2 Nm. After the system stabilizes, measure... , , The torque values ​​are 1.205 Nm, 44.88 Nm, and 75.93 KN respectively. Given that the gear transmission system 2 has a torque of 40 and the ball screw lead is 3 mm, then:

[0065] ,

[0066] 80.82%,

[0067] .

[0068] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A testing fixture for the efficiency of an EMB drive system, characterized in that, It includes, from left to right, an input motor mounting plate, a first bearing housing, a gear transmission system mounting plate, a second bearing housing, a third bearing housing, and a ball screw system mounting plate, which are fixed in sequence. An input motor is fixed to the left side of the input motor mounting plate; An input torque sensor is installed between the input motor mounting plate and the first bearing housing. The two sides of the input torque sensor are respectively connected to the input motor and the first bearing housing via a first coupling. An input gear shaft and a gear transmission system are sequentially connected between the first bearing housing and the gear transmission system mounting plate. An output gear shaft is installed between the gear transmission system mounting plate and the second bearing housing, and the two ends of the output gear shaft are respectively connected to the gear transmission system and the second bearing housing; An output torque sensor is installed between the second bearing housing and the third bearing housing. The two sides of the output torque sensor are respectively connected to the second bearing housing and the third bearing housing via a second coupling. A ball screw input spline is connected between the third bearing housing and the ball screw system mounting plate. The ball screw system is connected to the right side of the mounting plate, and the ball screw system is connected to the ball screw input spline and the force sensor on both sides respectively.

2. The testing fixture for the efficiency of an EMB transmission system according to claim 1, characterized in that, A pad is placed below the force sensor to align the center of the force sensor with the center of the piston of the ball screw system.

3. The testing fixture for the efficiency of an EMB transmission system according to claim 1, characterized in that, It also includes a base plate, on which the input motor mounting plate, the first bearing seat, the gear transmission system mounting plate, the second bearing seat, the third bearing seat, and the ball screw system mounting plate are all fixed and arranged sequentially along a straight line so that the center lines of each shaft system are collinear.

4. A testing fixture for the efficiency of an EMB transmission system according to any one of claims 1 to 3, characterized in that, The first bearing housing, the second bearing housing, and the third bearing housing are each provided with rolling bearings. The input gear shaft, the output gear shaft, and the ball screw input spline are each supported in their respective bearing housings by corresponding rolling bearings.

5. The testing fixture for the efficiency of an EMB transmission system according to claim 4, characterized in that, The first coupling and the second coupling are flexible couplings.

6. The testing fixture for the efficiency of an EMB transmission system according to claim 5, characterized in that, The ball screw system includes a ball screw fixedly connected to the input spline of the ball screw, a ball nut threaded with the ball screw, and a piston fixedly connected to the ball nut and passing through the brake caliper cylinder. The end of the piston along the clamping direction abuts against the force measuring surface of the force sensor.

7. The testing fixture for the efficiency of an EMB transmission system according to claim 6, characterized in that, The force sensor is arranged between the two clamping surfaces of the brake caliper, and the brake caliper is fixedly mounted on the ball screw mounting plate so that the force sensor is aligned with the axis of the ball screw.

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