Calibration device for level-type wheel alignment measuring instruments and portable brake performance testers

Abstract

This invention relates to a calibration device, specifically a calibration device suitable for a level wheel alignment measuring instrument and a portable brake performance tester. The calibration device for level wheel alignment measuring instruments and portable brake performance testers includes a base, a frame erected on the base, a rotating shaft mounted on the frame, a detection turntable connected to the rotating shaft, a drive device for driving the rotating shaft to rotate, an angle encoder mounted on the rotating shaft, and a detection display system electrically connected to the angle encoder. This invention uses a bidirectional (lateral and longitudinal) fixed detection table as the support mechanism for the measuring and testing instruments. An angle is rotated via a rotating mechanism and detected by the angle encoder and detection display system, thereby quickly and accurately calibrating the level wheel alignment measuring instrument and the portable brake performance tester.

Description

Technical Field

[0001] This invention relates to a calibration device, specifically a calibration device suitable for level wheel alignment measuring instruments and portable brake performance testers. Background Technology

[0002] The alignment parameters of a car's steering wheels (usually the front wheels) include camber angle, caster angle, and kingpin inclination angle. Their accuracy (strictly verified during car design) directly affects the car's safe operation. Due to long-term use, incorrect operation, and external influences, these alignment parameters often change, deviating from the original design requirements, which is extremely dangerous. Therefore, the alignment parameters of the steering wheels must be checked regularly, primarily using a "leveling wheel alignment measuring instrument." According to JJF1377-2012 "Calibration Specification for Leveling Wheel Alignment Measuring Instruments," the technical specifications for the leveling wheel alignment measuring instrument's built-in "leveling instrument" are as follows: the indication error for camber angle, caster angle, and kingpin inclination angle should be "±0.5°" or "±5%"; the indication error of the standard used to calibrate the leveling wheel alignment measuring instrument should not exceed ±3'. However, at present, no dedicated instruments and equipment have been developed in China for measuring and calibrating the metrological performance of the level wheel alignment measuring instrument itself, making the calibration of the level wheel alignment measuring instrument difficult to implement.

[0003] Furthermore, the mandatory national standard GB21861-2014 "Inspection Items and Methods for Motor Vehicle Safety Technical Performance" stipulates that vehicles with questionable safety performance should undergo "road testing" using a portable brake performance tester during vehicle safety inspections. The calibration of the portable brake performance tester should be carried out according to JJF 1168-2007 "Calibration Specification for Portable Brake Performance Tester". JJF1168-2007 "Calibration Specification for Portable Brake Performance Tester" stipulates that the calibration of the portable brake performance tester is divided into two parts: "static calibration" and "dynamic calibration". The standard used for "static calibration" - the "static calibration device" with a calibration platform - has a rotation range of not less than 0° to 180°; an angle resolution of not more than 0.1°; and an angle indication error of not more than ±0.2°.

[0004] Currently, the calibration of level wheel alignment measuring instruments is mainly carried out by combining general length (angle) measuring instruments. The temporary assembly of the calibration device is cumbersome, unreliable, and difficult to guarantee repeatability. There are many instruments or devices on the market for static calibration of "portable brake performance testers", which are varied and have their own advantages and disadvantages. They generally have low accuracy and can only be used for single calibration of "portable brake performance testers". Summary of the Invention

[0005] The purpose of this invention is to provide a calibration device that can be used to calibrate a level wheel alignment measuring instrument and a portable brake performance tester, addressing the problems existing in the prior art.

[0006] The specific technical solution of the present invention is as follows: A calibration device suitable for a level wheel alignment measuring instrument and a portable brake performance tester includes a base, a frame erected on the base, a rotating shaft mounted on the frame, a detection turntable connected to the rotating shaft, a drive device for driving the rotating shaft to rotate, an angle encoder mounted on the rotating shaft, and a detection display system electrically connected to the angle encoder. The detection turntable is composed of a vertical plate perpendicular to the horizontal plane and a horizontal plate parallel to the horizontal plane. The rotating shaft is parallel to the horizontal plane, and the vertical plate is perpendicularly connected to the rotating shaft. Furthermore, the detection and display system includes a microcontroller, an angle encoder electrically connected to the microcontroller, a reset chip, a memory, a keyboard scanning matrix, an LED display dynamic scanning drive circuit, a line filter, and a switching power supply; Furthermore, the drive device includes a turbine mounted on a rotating shaft and a handwheel mounted on the frame. A worm gear is provided on the handwheel shaft, and the turbine meshes with the worm gear. Furthermore, the testing turntable is provided with a fixing device, which includes a stud vertically disposed on the horizontal plate and a pressure plate fitted on the stud. The pressure plate can move along the axial direction of the stud. Furthermore, the angle encoder is an incremental angle encoder; Furthermore, the base is provided with retractable support legs at its bottom.

[0007] Working principle of a level wheel alignment measuring instrument: The leveling wheel alignment measuring instrument consists of leveling instruments A, B, C, and D. Leveling instrument A is used to measure the wheel camber angle α, with a measurement range of -5° to +5°; leveling instrument B is used to measure the wheel kingpin caster angle γ, with a measurement range of -3° to +11°; leveling instrument C is used to measure the wheel kingpin inclination angle β, with a measurement range of 0° to 16°; and leveling instrument D is the basic leveling instrument of the entire leveling wheel alignment measuring instrument. The chassis of the leveling wheel alignment measuring instrument has a magnetic mounting base for attaching to the wheel hub surface to measure the relevant alignment angles of the wheel.

[0008] Working principle of portable brake performance tester: The measuring element of a portable brake performance tester is an acceleration / deceleration sensor. To verify the accuracy of the portable brake performance tester, standard acceleration / deceleration values ​​are necessary, and one of the most basic and standard acceleration / deceleration values ​​is gravitational acceleration. Therefore, by utilizing the change in the angle between the acceleration / deceleration axis of the portable brake performance tester's sensor and the Earth's plumb line, the sensor can acquire different acceleration values.

[0009] The present invention has the following beneficial effects: Currently, there are no instruments or devices in China specifically designed for calibrating "level wheel alignment measuring instruments". Calibration is generally performed by combining general length (angle) measuring instruments. The temporary calibration devices are cumbersome, unreliable, and difficult to guarantee repeatability.

[0010] There are many instruments or devices for static calibration of "portable brake performance testers", each with its own advantages and disadvantages. They generally have low accuracy and can only be used for single calibration of "portable brake performance testers".

[0011] Currently, there are no instruments or devices in China that can calibrate both "level wheel alignment measuring instruments" and "portable brake performance testers". This invention uses a bidirectional (lateral and longitudinal) fixed testing platform as the carrier mechanism for the measuring and testing instruments. The rotation angle is measured by a rotating mechanism and detected by an angle encoder and a detection display system, thereby quickly calibrating the level wheel alignment measuring instrument and the portable brake performance tester. After the successful development of this calibration device, it can be used for multiple purposes while ensuring high accuracy of calibration. It is convenient and economical for metrology departments to verify / calibrate these two types of instruments.

[0012] Currently, motor vehicle inspection lines in the transportation sector are springing up across the country. Developing and manufacturing this system will ensure the accuracy and reliability of motor vehicle safety performance technical indicator measurement, providing a guarantee for the safety performance of motor vehicles nationwide, promoting the sustainable development of my country's social economy and enhancing the competitiveness of my country's related automotive industries, and has good economic, social and ecological benefits. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a module connection diagram of the detection and display system of the present invention; Figure 3 This is a schematic diagram of the installation of the leveling wheel alignment measuring instrument when calibrating the leveling measuring instrument C of the leveling wheel alignment measuring instrument of the present invention. Figure 4This is a schematic diagram of the installation of the leveling wheel alignment measuring instrument when calibrating leveling measuring instruments A and B of the leveling wheel alignment measuring instrument of the present invention. Figure 5 This is a schematic diagram of a level wheel alignment measuring instrument. Detailed Implementation

[0014] like Figure 1 and Figure 2 The leveling wheel alignment measuring instrument and portable brake performance tester calibration device shown includes a base 1, a frame 2 vertically mounted on the base 1, a rotating shaft 3 mounted on the frame 2, a detection turntable 4 connected to the rotating shaft 3, a drive device 5 for driving the rotating shaft 3 to rotate, an angle encoder 6 mounted on the rotating shaft 3, and a detection display system 7 electrically connected to the angle encoder 6. The detection turntable 4 is formed by connecting a vertical plate 4-1 perpendicular to the horizontal plane and a horizontal plate 4-2 parallel to the horizontal plane. The rotating shaft 3 is parallel to the horizontal plane. The vertical plate 4-1 is perpendicularly connected to the rotating shaft 3. The detection display system includes a microcontroller 7-1, a reset chip 7-2 electrically connected to the microcontroller 7-1, a memory 7-3, and a keyboard scanning matrix 7. -4. LED display dynamic scanning drive circuit 7-5, line filter 7-6, switching power supply 7-7; the angle encoder 6 is electrically connected to the microcontroller 7-1; the drive device 5 includes a turbine 5-1 mounted on the rotating shaft 3 and a handwheel 5-2 mounted on the frame 2; a worm gear 5-3 is mounted on the handwheel shaft of the handwheel 5-2, and the turbine 5-1 meshes with the worm gear 5-3; a fixing device 8 is mounted on the detection turntable 4, the fixing device 8 includes a stud 8-1 vertically mounted on the horizontal plate 4-2 and a pressure plate 8-2 fitted on the stud 8-1, the pressure plate 8-2 can move along the axial direction of the stud 8-1; the angle encoder 6 is an incremental angle encoder; the bottom of the base 1 is provided with a telescopic support leg 9.

[0015] Example 1

[0016] like Figure 3 and Figure 5 As shown, when calibrating the leveling instrument C of the leveling wheel alignment measuring instrument 10 using the device of the present invention, the base 1 of the device is placed on a flat, hard platform. The adjustment knobs of each retractable support leg 9 at the bottom of the device are rotated to keep the device horizontal relative to the ground. The magnetic base at the bottom of the leveling wheel alignment measuring instrument 10 is then attached to the longitudinal plate 4-1 and coaxial with the rotating shaft 3. The calibration of the leveling instrument C of the leveling wheel alignment measuring instrument 10 begins, and the specific calibration steps are as follows: a) Rotate the handwheel 5-2 of the drive device 5 to drive the detection turntable 4 to rotate along the shaft 3. The detection turntable 4 drives the level wheel alignment measuring instrument 10 to rotate, so that the bubble of the level measuring device D of the level wheel alignment measuring instrument 10 is in the horizontal middle position. b) Adjust the tilt adjustment screw of the leveling instrument C so that one end of the bubble of the leveling instrument C is aligned with the 0° mark of the leveling instrument C, and set the value of the detection display system 7 to zero; c) The handwheel 5-2 of the rotary drive device 5 drives the detection turntable 4 to rotate along the rotating shaft 3, and the longitudinal plate 4-1 of the detection turntable 4 drives the level wheel positioning measuring instrument 10 to rotate. d) During the rotation of the level wheel alignment measuring instrument 10, the readings are taken from one end of the level measuring instrument C (as described in step b) when it is aligned with the level measuring instrument C markings at 5°, 10°, and 15°, respectively, indicating the inclination angle β of the level measuring instrument's kingpin. i The device of the present invention detects and displays the angle θ displayed by the display system 7 at 5°, 10°, and 15° respectively. i ; e) Calculate the inclination angle β of the leveling instrument's main pin according to algorithm formulas (1) and (2) respectively. i Indication error Δβ i and relative error δβ i .

[0017] In the formula: Δβ i --Indication error of the inclination angle of the main pin of the leveling instrument at the i-th measurement point (i=1 ,2 ,3), in degrees (°); δβ i --The relative error of the inclination angle of the kingpin of the leveling instrument at the i-th measurement point; β i --Inclination angle of the kingpin of the leveling instrument at the i-th measurement point, in degrees (°); θ i --The angle displayed by the i-th measurement point detection and display system 7, in degrees (°); η θ --Proportional coefficient (η when the wheel turns 20° to the left or right) θ =1.46; when the wheel turns 14° to the left and right, η θ =2.07; When the wheel turns 10° to the left and right, η θ =2.87).

[0018] Example 2

[0019] like Figure 4 and Figure 5 As shown, when calibrating the leveling instrument A of the leveling wheel alignment measuring instrument 10 using the device of the present invention, the base 1 of the device is placed on a flat, hard platform. The adjustment knobs of each retractable support leg 9 at the bottom of the base 1 are rotated to keep the device horizontal relative to the ground. The bottom magnetic suction base of the leveling wheel alignment measuring instrument 10 is then attached to the horizontal plate 4-2. The calibration of the leveling instrument A of the leveling wheel alignment measuring instrument 10 begins. The specific calibration steps are as follows: f) Rotate the handwheel 5-2 of the drive device 5 to drive the horizontal plate 4-2 of the detection turntable 4 to rotate parallel to the axis of the rotating shaft 3 to a vertical position; g) Manually and gently rotate the magnetic base of the level wheel alignment measuring instrument 10 relative to the horizontal plate 4-2 so that the bubble of the level measuring instrument D of the level wheel alignment measuring instrument 10 is in the horizontal middle position. h) Rotate the handwheel 5-2 of the drive device 5 to drive the horizontal plate 4-2 of the detection turntable 4 to rotate parallel to the axis of the rotating shaft 3, so that one end of the bubble of the level measuring instrument A is aligned with the 0° mark of the level measuring instrument A, and set the value of the detection display system 7 to zero. i) Rotate the handwheel 5-2 of the drive device 5 to drive the horizontal plate 4-2 of the detection turntable 4 to rotate parallel to the axis of the rotating shaft 3, and read the values ​​of one end of the bubble of the leveling instrument A mentioned in step h) aligned with the graduation lines of the leveling instrument A at +1°, +3°, +5°, -1°, -3°, and -5°, respectively, i.e., the inclination angle α of the leveling instrument. j The device of the present invention detects the angle displayed by the display system 7 at +1°, +3°, +5°, -1°, -3°, and -5° respectively. ; j) Calculate the outward tilt angle α of the leveling instrument according to algorithm formulas (3) and (4). j Indication error Δα j And the relative error δαj.

[0020] In the formula: Δα j --Indication error of the outward tilt angle of the leveling instrument at the j-th measurement point (j=1,2,3), in degrees (°); δα j --The relative error of the outward tilt angle of the leveling instrument at the j-th measurement point; α j -- The outward tilt angle of the leveling instrument at the j-th measurement point, in degrees (°); --The angle displayed by the system at the j-th measurement point, in degrees (°).

[0021] Example 3

[0022] like Figure 4 and Figure 5 As shown, when calibrating the leveling instrument B of the leveling wheel alignment measuring instrument 10 using the device of the present invention, the base 1 of the device is placed on a flat, hard platform. The adjustment knobs of each retractable support leg 9 at the bottom of the base 1 are rotated to keep the device horizontal relative to the ground. The bottom magnetic base of the leveling wheel alignment measuring instrument 10 is then attached to the horizontal plate 4-2, and the calibration of the leveling instrument B of the leveling wheel alignment measuring instrument 10 begins. The specific calibration steps are as follows: k) Rotate the handwheel 5-2 of the drive device 5 to drive the horizontal plate 4-2 of the detection turntable 4 to rotate parallel to the axis of the rotating shaft 3 to a vertical position; l) Manually and gently rotate the magnetic base of the level wheel alignment measuring instrument 10 relative to the horizontal plate 4-2 so that the bubble of the level measuring instrument D of the level wheel alignment measuring instrument 10 is in the horizontal middle position. m) Adjust the tilt adjustment screw of the leveling instrument B so that one end of the bubble of the leveling instrument B is aligned with the 0° mark of the leveling instrument B, and set the value of the detection display system 7 to zero. n) Rotate the handwheel 5-2 of the drive device 5 to drive the horizontal plate 4-2 of the detection turntable 4 to rotate parallel to the axis of the rotating shaft 3, and read the readings respectively at one end of the bubble of the leveling instrument B mentioned in step m) aligned with the leveling instrument B graduations at -3°, +3°, +6°, and +9°. The back tilt angle γ of the kingpin of the leveling instrument k The device of the present invention detects and displays the angle ψ displayed by the display system 7 at -3°, +3°, +6°, and +9° respectively. k ; o) Calculate the back tilt angle γ of the leveling instrument's main pin according to algorithm formulas (5) and (6). k Indication error Δγ k and relative error δγ k .

[0023] In the formula: Δγ k --Indication error of the backslope angle of the leveling instrument at the k-th measurement point (k=1,2,3,4), in degrees (°); δγ k --The relative error of the back tilt angle of the leveling instrument's main pin at the k-th measuring point; γ k -- Backslope angle of the leveling instrument's main pin at the k-th measuring point, in degrees (°); ψ k--The angle displayed by the k-th measurement point detection and display system 7, in degrees (°); η θ --Proportional coefficient (η when the wheel turns 20° to the left or right) θ =1.46; when the wheel turns 14° to the left and right, η θ =2.07; When the wheel turns 10° to the left and right, η θ =2.87).

[0024] Example 4

[0025] When calibrating a portable brake performance tester using the device of this invention, place the base 1 of the device on a flat, hard platform, and rotate the adjustment knobs of each retractable support leg 9 at the bottom of the base 1 to keep the device horizontal relative to the ground. The specific calibration steps are as follows: p) Place the portable braking performance tester (or the one with its own split sensor) on the horizontal plate 4-2 of the test turntable 4, so that the mark indicating the vehicle's forward direction on the portable braking performance tester (or the one with its own split sensor) is perpendicular to the axis of the turntable 3. q) Set both the values ​​displayed on the portable brake performance tester and the test display system 7 to zero; r) Rotate the handwheel 5-2 of the drive device 5 to drive the test turntable 4 to rotate along the rotating shaft 3. The horizontal plate 4-2 drives the portable braking performance tester (or the built-in split sensor) to rotate. During the rotation, the relative position of the portable braking performance tester (or the built-in split sensor) and the horizontal plate 4-2 described in step p) does not change. s) Read the angle φ displayed by the detection and display system 7 of this device. λ The first measurement value X of the portable braking performance tester at 12°, 24°, 37°, 53°, and 90° respectively. λ1 .

[0026] t) Repeat steps q) to s) twice, and read the second and third measurement values ​​X from the portable brake performance tester. λ2 X λ3 .

[0027] u) Based on algorithm formula (7), calculate the angle φ displayed by the detection display system 7 respectively. λ The average of three measurements taken by the portable braking performance tester at 12°, 24°, 37°, 53°, and 90°. In the formula: --The average of three measurements taken by the portable braking performance tester at measurement point λ (λ = 1, 2, 3, 4, 5), in meters per second squared (m / s). 2 ); X λ1 X λ2 X λ3 --These represent the 1st, 2nd, and 3rd measurements taken by the portable braking performance tester at the λth measurement point, in meters per second squared (m / s). 2 ); v) Calculate the angle φ displayed by the detection display system 7 according to the algorithm formula (8). λ The standard deceleration value A corresponding to the device of the present invention at angles of 12°, 24°, 37°, 53°, and 90° is... λ .

[0028] A λ =sinφ λ ×9.80 (8) A λ --The standard deceleration value corresponding to the invention device at the λth measurement point, in meters per second squared (m / s²) 2 ); φ λ --The angle displayed by the λth measurement point detection and display system 7, in degrees (°).

[0029] w) Calculate the angle φ displayed by the detection display system 7 according to algorithm formulas (9) and (10) respectively. λ The indication error Δ of the portable braking performance tester at 12° and 24° λ and the repeatability of the indicated value Δ Zλ .

[0030] Δ Zλ = X λmax - X λmin (10) In the formula: Δ λ --Indication error of the portable braking performance tester at the λth measurement point, in meters per second squared (m / s) 2 ); Δ Zλ --The repeatability of the portable braking performance tester reading at the λth measurement point, in meters per second squared (m / s) 2 ); X λmax --At the λth measurement point, the maximum value among the three measurements taken by the portable braking performance tester, expressed in meters per second squared (m / s). 2 ); Xλmin --At the λth measurement point, the minimum value among the three measurements taken by the portable braking performance tester under calibration, in meters per second squared (m / s) 2 ); x) Calculate the angle φ displayed by the detection display system 7 according to algorithm formulas (11) and (12). λ The relative error δ of the portable braking performance tester at 37°, 53°, and 90°. λ and relative repeatability δ Zλ .

[0031] In the formula: δ λ --Relative error of the portable braking performance tester at the λth measurement point; δ Zλ --Relative repeatability of the portable braking performance tester at the λth measurement point.

Claims

1. A calibration device suitable for leveling wheel alignment measuring instruments and portable brake performance testers, characterized in that: The device includes a base (1), a frame (2) vertically mounted on the base (1), a rotating shaft (3) mounted on the frame (2), a detection turntable (4) connected to the rotating shaft (3), a drive device (5) for driving the rotating shaft (3) to rotate, an angle encoder (6) mounted on the rotating shaft (3), and a detection display system (7) electrically connected to the angle encoder (6). The detection turntable (4) is formed by connecting a vertical plate (4-1) perpendicular to the horizontal plane and a horizontal plate (4-2) parallel to the horizontal plane. The rotating shaft (3) is parallel to the horizontal plane, and the vertical plate (4-1) is perpendicularly connected to the rotating shaft (3).

2. The calibration device for a level wheel alignment measuring instrument and a portable brake performance tester as described in claim 1, characterized in that: The detection and display system includes a microcontroller (7-1), a reset chip (7-2) electrically connected to the microcontroller (7-1), a memory (7-3), a keyboard scanning matrix (7-4), an LED display dynamic scanning drive circuit (7-5), a line filter (7-6), and a switching power supply (7-7). The angle encoder (6) is electrically connected to the microcontroller (7-1).

3. The calibration device for a level wheel alignment measuring instrument and a portable brake performance tester as described in claim 1, characterized in that: The drive device (5) includes a turbine (5-1) mounted on a rotating shaft (3) and a handwheel (5-2) mounted on the frame (2). A worm gear (5-3) is mounted on the handwheel shaft of the handwheel (5-2), and the turbine (5-1) meshes with the worm gear (5-3).

4. The calibration device for a level wheel alignment measuring instrument and a portable brake performance tester as described in claim 1, characterized in that: The testing turntable (4) is provided with a fixing device (8), which includes a stud (8-1) vertically arranged on the horizontal plate (4-2) and a pressure plate (8-2) fitted on the stud (8-1). The pressure plate (8-2) can move along the axial direction of the stud (8-1).

5. The calibration device for a level wheel alignment measuring instrument and a portable brake performance tester as described in claim 1, characterized in that: The angle encoder (6) is an incremental angle encoder.

6. The calibration device for a level wheel alignment measuring instrument and a portable brake performance tester as described in claim 1, characterized in that: The base (1) is provided with retractable support legs (9) at its bottom.

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