Tire rolling resistance test equipment and test method

Abstract

The invention relates to the field of tire testing, in particular to tire rolling resistance testing equipment and a testing method.The tire rolling resistance testing equipment comprises a loading device, a tool shaft, a sensing assembly, a drum wheel driving device and a drum wheel, the loading device comprises a loader and a loading tool, and the sensing assembly comprises a torque sensor and a fixing frame; the loading device can drive the loading tool to enable the mounting position to be close to or far away from the drum wheel, and the drum wheel driving device can drive the drum wheel to rotate. The torque sensor is arranged at the wheel axle of the tire to be measured and only measures one of the six-degree-of-freedom force or torque, the loading tool limits the tool shaft, the rolling resistance torque of the tire to be measured is effectively transmitted to the torque sensor at the other end of the tool shaft, and therefore the crosstalk problem of the force or torque of multiple degrees of freedom is avoided, and the measurement accuracy is improved. Errors caused by other component forces are effectively avoided, and the measurement precision is greatly improved.

Description

Technical Field

[0001] The present invention relates to the field of tire testing, and particularly to a tire rolling resistance testing device and a testing method. Background Art

[0002] As one of the mechanical properties of tires, tire rolling resistance has an important impact on aircraft, fuel economy, braking performance, handling stability, and tire service life. At present, the high speed, large load, and other external disturbances of aircraft tires pose technical challenges to the measurement of tire rolling resistance.

[0003] In a tire testing device, a drum driving device is used to drive a drum to rotate, and then drive a tire located on the outer periphery of the drum to roll, so as to simulate the way of tire contact with the road surface to measure the rolling resistance. The contact force between the drum and the tire is provided by a loading device. During the test, the tire is installed on a rim, and the loading device transfers the load through the rim to the tire to press the tire against the outer periphery of the drum.

[0004] In the prior art, a six-component force sensor is used to study the force condition of the tire. When in use, the six-component force sensor is usually assembled with a rim adapter and a tire to form a sensor assembly, while keeping the six-component force sensor relatively fixed to the tire. However, the six-component force sensor measures forces or torques in six degrees of freedom, including force components in three linear directions (X, Y, Z axes) and torque components in three rotational directions (torques about the X, Y, Z axes). When only studying the force or torque in one direction, it is not appropriate to use a six-component force sensor to avoid crosstalk caused by forces or torques in the other five directions to the measurement result, resulting in a large measurement error.

[0005] In addition, some solutions use a torque sensor installed on the power output end of the drum driving device. According to the torque measurement result and through conversion, the rolling friction force of the tire is obtained. However, the drum usually has a high mass, large wind resistance, bearing resistance, etc. These factors will increase the error of the torque sensor. Especially in the case of small-sized tires or low-load working conditions, it is difficult to ensure the measurement accuracy. Summary of the Invention

[0006] The purpose of the present invention is to provide a tire rolling resistance testing device. By installing the tire to be tested at the tooling shaft, the torque sensor measures the rolling resistance torque at the wheel shaft of the tire to be tested, thereby avoiding the crosstalk problem of forces or torques in other degrees of freedom and effectively improving the measurement accuracy.

[0007] The present invention provides the following technical solution: A tire rolling resistance testing device, comprising: a loading device, a tooling shaft, a sensing assembly, a drum driving device, and a drum;

[0008] The loading device includes a loader and a loading tooling. The loading tooling is installed at the power output end of the loader.

[0009] The loading tooling is provided with an installation hole. The installation hole penetrates through the front and rear end faces of the loading tooling. The tooling shaft is inserted through the installation hole, and a rotating bearing is arranged between the tooling shaft and the installation hole to achieve rotational connection with the loading tooling.

[0010] The sensing assembly is arranged at the rear end of the loading tooling. The sensing assembly includes a fixing bracket and a torque sensor. The fixing bracket is fixedly connected to the loading tooling. The torque sensor is installed on the fixing bracket, and the measuring end of the torque sensor is connected to the rear end of the tooling shaft.

[0011] An installation position for installing a tire to be measured is provided on the outer periphery of the tooling shaft protruding from the front end of the loading tooling.

[0012] The drum is installed at the power output end of the drum driving device, and the drum is arranged on one side in the radial direction of the installation position.

[0013] Wherein, the loading device can drive the loading tooling to slide along the radial direction of the drum, so that the installation position approaches or moves away from the drum, and the drum driving device can drive the drum to rotate.

[0014] Preferably, the loading tooling includes an upper plate, a lower plate and side plates. The upper plate and the lower plate are arranged at intervals up and down. The upper and lower ends of the side plates are respectively fixedly connected to the upper plate and the lower plate. The installation hole is opened on the side plates. The loading tooling is installed at the power output end of the loader through the upper plate, and the fixing bracket is fixedly connected to the rear side of the side plates.

[0015] Preferably, the number of the side plates is two. Each side plate is provided with an installation hole. The two side plates are arranged at intervals along the axial direction of the tooling shaft. A limiting portion is arranged along the circumferential wall of the installation hole. The limiting portion is fixedly connected to the inner side of the side plates. The limiting portion defines a through hole, and the through hole is communicated with the installation hole. A limiting member is sleeved on the tooling shaft. The limiting member is installed outside the installation hole and abuts against the rotating bearing to abut the rotating bearing against the inner side of the limiting portion.

[0016] Preferably, the two installation holes are respectively defined as: a first installation hole and a second installation hole. The limiting member installed outside the first installation hole is defined as a first limiting member, and the limiting member installed outside the second installation hole is defined as a second limiting member. The first limiting member is fixedly connected to the rear end of the tooling shaft.

[0017] The tooling shaft protrudes from the front end of the loading tooling, and a shoulder is provided at an interval. The shoulder is arranged at the rear end of the installation position at an interval, and the second limiting member is rotatably connected to the tooling shaft and abuts against one side of the shoulder.

[0018] Preferably, the fixing frame includes a transition flange and a plurality of connecting screws. The transition flange is fixedly connected to the rear side of the side plate through the connecting screws, the torque sensor is fixedly connected to the front side of the transition flange, and the torque sensor is arranged at an interval from the connecting screws.

[0019] Preferably, the upper plate is provided with bolt holes, and the loading tooling is fixedly connected to the power output end of the loader through the bolt holes.

[0020] Preferably, a tire mounting bearing is sleeved on the installation position. The tire mounting bearing is connected to the installation position, and the tire to be tested is mounted on the installation position through the tire mounting bearing.

[0021] Preferably, the tire rolling resistance testing device further includes a flange assembly. The flange assembly is arranged at an interval from the fixing frame, and the measuring end of the torque sensor is connected to the tooling shaft through the flange assembly.

[0022] This application also provides a tire rolling resistance testing method, which uses the tire rolling resistance testing device described above and includes:

[0023] S1. Install the tooling shaft to the loading tooling and the torque sensor. Fix the torque sensor to the loading tooling through the fixing frame, mount the tire to be tested on the installation position, and the drum driving device drives the drum to rotate at a set test speed.

[0024] S2. Select a test load within the specified test load range, adjust the loading device so that the load applied by the tire to be tested to the drum is the test load. When ensuring that the rotation speed of the tire to be tested is the same as that of the drum, select the minimum value of the test load through experiments and define it as the critical load.

[0025] S3. Adjust the loading device so that the load applied by the tire to be tested to the drum is the critical load. When the tire to be tested reaches a stable speed, record the reading M1 of the torque sensor at this time. According to M1, the load radius r from the center of the axis of the tire to be tested to the outer surface of the drum, and the radius R of the drum, calculate the additional loss f. The calculation formula for the additional loss f is: f = M1 / r(1 + r / R).

[0026] S4. Adjust the loading device so that the load exerted by the tire under test on the drum is the set test load. After the tire under test reaches a stable speed, record the reading M2 of the torque sensor, and calculate the rolling resistance F of the tire under test based on M2, the load radius r from the center of the tire under test to the outer surface of the drum, the radius R of the drum, and the additional loss f. The calculation formula for the rolling resistance F of the tire under test is: F = M2 / r(1 + r / R) - f.

[0027] Preferably, the tire rolling resistance test method includes: after step S1 and before step S2, adjust the loading device so that the load exerted by the tire under test on the drum is the test load until the reading of the torque sensor does not change.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: Compared with using a six-component force sensor for measurement in the prior art, the torque sensor in this application is arranged at the wheel axle of the tire under test and only measures one of the six degrees of freedom of force or torque. Through the limit of the tooling shaft by the loading tooling, the rolling resistance torque of the tire under test is effectively transmitted to the torque sensor at the other end of the tooling shaft, thus avoiding the crosstalk problem of forces or torques in multiple degrees of freedom, effectively avoiding errors caused by other component forces, and greatly improving the measurement accuracy; The present invention can select a torque sensor with a suitable range according to different rolling friction force ranges, so as to achieve the best test accuracy; Only by replacing the loading device with different specifications, the dynamic torque measurement of various tires can be completed, which is applicable to a variety of tire specifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Structural schematic diagram of the tire rolling resistance test equipment of the present application;

[0030] Figure 2 Structural schematic diagram of the installation of the rotating bearing on the tooling shaft of the present application;

[0031] Figure 3 Structural schematic diagram of the tooling shaft of the present application;

[0032] Figure 4 Structural schematic diagram of the installation of the rotating bearing on the loading tooling of the present application;

[0033] Figure 5 Structural schematic diagram of the loading tooling of the present application;

[0034] Figure 6 Installation schematic diagram of the tire under test of the present application;

[0035] Figure 7 Structural schematic diagram of the sensing component of the present application;

[0036] Figure 8This is a schematic diagram of the rolling resistance test condition of this application.

[0037] In the figure:

[0038] 1. Loading tooling; 11. Mounting holes; 111. First mounting hole; 112. Second mounting hole; 12. Upper plate; 121. Bolt hole; 13. Lower plate; 14. Side plate; 15. Limiting part; 151. Through hole; 2. Tooling shaft; 21. Rotating bearing; 22. Mounting position; 221. Tire mounting bearing; 23. Limiting piece; 231. First limiting piece; 232. Second limiting piece; 24. Axle shoulder; 3. Sensing assembly; 31. Fixed frame; 311. Transition flange; 312. Connecting screw; 32. Torque sensor; 4. Drum; 5. Tire to be tested; 6. Flange assembly; 61. Connecting flange; 611. Connecting hole. Detailed implementation manners

[0039] Next, the technical solutions in the embodiments of this application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this application.

[0040] In the description of the embodiments of this application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the embodiments of this application. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0041] In the description of the embodiments of this application, it should be noted that unless otherwise clearly specified and limited, the terms "mount", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a replaceable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be directly connected or indirectly connected through an intermediate medium. It can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of this application can be understood according to specific situations.

[0042] Combined with Figure 1-8As shown in the figure, some embodiments of the present application provide a tire rolling resistance test device, including: a loading device, a tooling shaft 2, a sensing assembly 3, a drum driving device (not specifically shown in the figure), and a drum 4; the loading device includes a loader (not specifically shown in the figure) and a loading tooling 1, and the loading tooling 1 is installed at the power output end of the loader; an installation hole 11 is formed in the loading tooling 1, the installation hole 11 penetrates through the front and rear end faces of the loading tooling 1, and the tooling shaft 2 is inserted into the installation hole 11, and a rotating bearing 21 is provided between the tooling shaft 2 and the installation hole 11 to achieve a rotating connection with the loading tooling 1; the sensing assembly 3 is arranged at the rear end of the loading tooling 1, and the sensing assembly 3 includes a fixing frame 31 and a torque sensor 32, the fixing frame 31 is fixedly connected to the loading tooling 1, the torque sensor 32 is installed on the fixing frame 31, and the measuring end of the torque sensor 32 is connected to the rear end of the tooling shaft 2; an installation position 22 for installing a tire under test 5 is provided on the outer periphery of the tooling shaft 2 protruding from the front end of the loading tooling 1; the drum 4 is installed at the power output end of the drum driving device, and the drum 4 is arranged on one side of the installation position 22 in the radial direction; wherein, the loading device can drive the loading tooling 1 to slide along the radial direction of the drum 4, so that the installation position 22 approaches or departs from the drum 4, and the drum driving device can drive the drum 4 to rotate.

[0043] When using the tire rolling resistance test equipment of the present application, the loading tooling 1 is installed at the power output end of the loader. The tooling shaft 2 is installed at the installation hole 11 through the rotating bearing 21, so that the loading tooling 1 plays a limiting role on the tooling shaft 2. The tire 5 to be tested is installed at the installation position 22. The measuring end of the torque sensor 32 is fixedly installed at the rear end of the tooling shaft 2. The fixing bracket 31 installed with the torque sensor 32 is fixedly connected to one side of the loading tooling 1. The drum 4 is driven to rotate by the drum driving device, and then the tire 5 to be tested located on the outer circumference of the drum 4 is driven to roll. The contact force between the test drum 4 and the tire is provided by the loading device. Exemplarily, the tire 5 to be tested is placed above the drum 4. The loader controls the loading tooling 1 to make the tooling shaft 2 descend along the radial direction of the drum 4, so that the tire 5 to be tested installed on the tooling shaft 2 increases the load on the drum 4, and the torque generated by the tire rolling resistance is measured in this way by simulating the contact mode between the tire 5 to be tested and the road surface, and then the tire rolling resistance is calculated. When the tire 5 to be tested rotates, the tooling shaft 2 does not rotate under the constraint of the torque sensor 32. Since the tooling shaft 2 is installed on the loading tooling 1, the loading device can constrain the axial force generated by the tire 5 to be tested, so that the tooling shaft 2 does not move axially and does not rotate with the tire 5 to be tested, ensuring that the tooling shaft 2 transmits the torque of the tire 5 to be tested to the torque sensor 32 without being interfered by other forces or torques. Then, the rolling friction force of the tire is obtained by conversion according to the value shown by the torque sensor 32, effectively improving the measurement accuracy. According to different rolling friction force ranges of the tire 5 to be tested, the torque sensor 32 in the present application can also be replaced to select a torque sensor 32 with a suitable range for measurement, so as to achieve the best test accuracy. By replacing the tooling shaft 2 with different specifications and the matching loading tooling 1, the present application can be applicable to the dynamic torque measurement of various specifications of tires 5 to be tested.

[0044] In order to better arrange the connection positions of the loader, the tooling shaft 2, the sensing assembly 3 and the loading tooling 1, further, the loading tooling 1 includes an upper plate 12, a lower plate 13 and a side plate 14. The upper plate 12 and the lower plate 13 are arranged at intervals up and down. The upper end and the lower end of the side plate 14 are respectively fixedly connected to the upper plate 12 and the lower plate 13. The installation hole 11 is opened on the side plate 14. The loading tooling 1 is installed at the power output end of the loader through the upper plate 12. The fixing bracket 31 is fixedly connected to the rear side of the side plate 14.

[0045] Further, the number of the side plates 14 is two, and each side plate 14 is provided with one mounting hole 11. The two side plates 14 are arranged at intervals along the axial direction of the tooling shaft 2. A limiting portion 15 is provided along the circumferential wall of the mounting hole 11. The limiting portion 15 is fixedly connected to the inner side of the side plate 14. The limiting portion 15 defines a through hole 151, and the through hole 151 communicates with the mounting hole 11. A limiting member 23 is sleeved on the tooling shaft 2. The limiting member 23 is installed outside the mounting hole 11 and abuts against the rotary bearing 21 to abut the inner side of the rotary bearing 21 against the limiting portion 15.

[0046] Installing two rotary bearings 21 on the tooling shaft 2 can better offset the axial force of the test tire on the tooling shaft 2. The limiting portions 15 on the two mounting holes 11 approach each other, so that the through hole 151 is close to the inside of the loading tooling 1, and the mounting hole 11 is close to the outside of the loading tooling 1. When the rotary bearing 21 is installed in the mounting hole 11, the limiting members 23 limit the rotary bearing 21 from the outside of the loading tooling 1, making the installation of the rotary bearing 21 more convenient.

[0047] Further, the two mounting holes 11 are respectively defined as: a first mounting hole 111 and a second mounting hole 112. The limiting member 23 installed outside the first mounting hole 111 is defined as a first limiting member 231, and the limiting member 23 installed outside the second mounting hole 112 is defined as a second limiting member 232. The first limiting member 231 is fixedly connected to the rear end of the tooling shaft 2; the tooling shaft 2 protrudes from the front end of the loading tooling 1 and is provided with a shoulder 24 at intervals. The shoulder 24 is arranged at intervals at the rear end of the mounting position 22. The second limiting member 232 is rotatably connected to the tooling shaft 2 and abuts against one side of the shoulder 24.

[0048] The tooling shaft 2 is usually provided with a shoulder 24. In this embodiment, when the tooling shaft 2 is installed on the loading tooling 1, the mounting holes 11 are all located on the same side of the shoulder 24. Specifically, the first mounting hole 111 is located at the rear end of the tooling shaft 2, and the second mounting hole 112 is located close to the shoulder 24 and abuts against the shoulder 24 through the second limiting member 232. Exemplarily, the first limiting member 231 is a lock nut, and the axial movement of the rotary bearing 21 is restricted by the lock nut and the limiting portion 15. The second limiting member 232 is a bearing retainer. After the rotary bearing 21 is installed in the second mounting hole 112, the bearing retainer and the shoulder 24 abut against the outside of the second mounting hole 112 in sequence. Such a reasonable layout of the loading device can effectively limit the axial movement of the rotary bearing 21, so that the axial force of the tooling shaft 2 is constrained, which is beneficial to avoiding the influence of other component forces on the torque sensor 32 when the test tire rotates.

[0049] Furthermore, the fixing bracket 31 includes a transition flange 311 and a plurality of connecting screw rods 312. The transition flange 311 is fixedly connected to the rear side of the side plate 14 through the connecting screw rods 312. The torque sensor 32 is fixedly connected to the front side of the transition flange 311, and the torque sensor 32 is arranged at an interval from the connecting screw rods 312.

[0050] In this embodiment, a circle of bolt holes 121 is provided in the middle of the transition flange 311. The transition flange 311 is fixedly connected to the torque sensor 32 through the bolt holes 121. The transition flange 311 is connected to the side plate 14 through six connecting screw rods 312 to achieve the purpose of fixing the torque sensor 32. When it is necessary to keep the tooling shaft 2 unchanged and replace the torque sensor 32, after disconnecting the connection between the connecting screw rod 312 and the loading tooling 1, and the connection between the torque sensor 32, the connecting flange 61 and the tooling shaft 2, the replacement can be carried out. The operation is simple and it is also convenient to quickly position and install the new torque sensor 32 after replacement.

[0051] Furthermore, the upper plate 12 is provided with bolt holes 121, and the loading tooling 1 is fixedly connected to the power output end of the loader through the bolt holes 121. When using the tire rolling resistance test equipment of the present application, the load between the tire 5 to be tested and the drum 4 is mainly adjusted through the loading tooling 1. Specifically, the tooling shaft 2 on which the tire 5 to be tested is installed is installed on the loading tooling 1, and the upper plate 12 of the loading tooling 1 is fixedly connected to the power output end of the loader. The loader drives the loading tooling 1 to generate displacement in a certain direction to change the contact force between the tire 5 to be tested and the drum 4.

[0052] Furthermore, a tire mounting bearing 221 is sleeved on the mounting position 22. The tire mounting bearing 221 is connected to the mounting position 22, and the tire 5 to be tested is installed on the mounting position 22 through the tire mounting bearing 221.

[0053] Exemplarily, the test tire is detachably installed on the tire mounting bearing 221. A journal is provided on the test section. The tire mounting bearing 221 is fitted and installed with the journal to bear the load generated by the test tire during high-speed rolling. When the test tire rotates, the tire mounting bearing 221 also rotates accordingly. The tooling shaft 2 is restricted from rotating and only responsible for transmitting the torque of the test tire to the torque sensor 32. When it is necessary to adjust the load of the test tire on the drum 4, the loading tooling 1 is mainly adjusted, and the tooling shaft 2 transmits the acting force of the loading tooling 1 to the tire mounting bearing 221 to realize the adjustment of the load of the test tire. Specifically, the tire mounting bearing 221 includes a tire tapered roller bearing and a rim. The rim is fixedly installed with the tire tapered roller bearing, and the tire tapered roller bearing is connected to the mounting position 22. When using the tire rolling resistance test equipment, the rim and the tire tapered roller bearing suitable for the type of the tire 5 to be tested can be selected to install the tire 5 to be tested on the tooling shaft 2.

[0054] Furthermore, the tire rolling resistance testing device further includes a flange assembly 6. The flange assembly 6 is spaced apart from the fixed frame 31. The measuring end of the torque sensor 32 is connected to the tooling shaft 2 through the flange assembly 6.

[0055] In this embodiment, the flange assembly 6 includes two connecting flanges 61. The connecting flanges 61 are circumferentially and spacedly provided with connecting holes 611. The connecting holes 611 are specifically bolt connecting holes 611. The connecting holes 611 include an outer ring hole near the outer circumference of the connecting flange 61 and an inner ring hole near the middle of the connecting flange 61. The two connecting flanges 61 are fixedly connected through the outer ring holes. The connecting flange 61 is fixedly connected to the measuring end of the torque sensor 32 or the rear end of the tooling shaft 2 through the inner ring hole, so as to transmit the torque of the tire 5 to be measured at the installation position 22 of the tooling shaft 2 to the measuring end of the torque sensor 32. When it is necessary to replace the tooling shaft 2 of different specifications to correspondingly complete the dynamic torque measurement of various tires 5 to be measured, after disconnecting the connection between the loading tooling 1 and the tooling shaft 2 and the connection between the tooling shaft 2 and the flange assembly 6, it can be replaced. When it is necessary to keep the torque sensor 32 unchanged, the torque sensor 32 can be kept connected to the flange assembly 6, which is convenient for the newly replaced tooling shaft 2 to be quickly positioned and connected to the flange assembly 6, ensuring the coaxiality of the connection between the tooling shaft 2 and the measuring end of the torque sensor 32 and making the measurement data more accurate.

[0056] The present application also provides a tire rolling resistance testing method, which uses the above-mentioned tire rolling resistance testing device and includes:

[0057] S1. Install the tooling shaft 2 to the loading tooling 1 and the torque sensor 32. Fix the torque sensor 32 to the loading tooling 1 through the fixed frame 31. Install the tire 5 to be measured on the installation position 22. The drum driving device drives the drum 4 to rotate at a set test speed.

[0058] S2. Select a test load within the specified test load range, adjust the loading device so that the load applied by the tire 5 to be measured to the drum 4 is the test load. On the premise of ensuring that the rotation speed of the tire 5 to be measured is the same as the rotation speed of the drum 4, select the minimum value of the test load through experiments and define it as the critical load.

[0059] S3. Adjust the loading device so that the load applied by the tire under test 5 to the drum 4 is the critical load. After the tire under test 5 reaches a stable speed, record the reading M1 of the torque sensor 32, and calculate the additional loss f based on M1, the load radius r from the axis center of the tire under test 5 to the outer surface of the drum 4, and the radius R of the drum 4. The calculation formula for the additional loss f is: f = M1 / r(1 + r / R);

[0060] S4. Adjust the loading device so that the load applied by the tire under test 5 to the drum 4 is the set test load. When the tire under test 5 reaches a stable speed, record the reading M2 of the torque sensor 32, and calculate the rolling resistance F of the tire under test 5 based on M2, the load radius r from the center of the tire under test 5 to the outer surface of the drum 4, the radius R of the drum 4, and the additional loss f. The calculation formula for the rolling resistance F of the tire under test 5 is: F = M2 / r(1 + r / R) - f.

[0061] Specifically in step S1, after the tire under test 5 is installed on the installation position 22, preset condition adjustment is first performed, which specifically includes: starting the tire under test 5 to run for a period of time according to the test load and test speed to ensure that the tire under test 5 and the tire rolling resistance test equipment are in a stable state.

[0062] Steps S2 - S3 are mainly for the separate measurement of the additional loss. The goal is to measure the additional loss caused by factors such as air resistance and bearing friction for deduction in the rolling resistance calculation. Under the action of the critical load, ensure that the tire under test 5 does not have relative sliding with the drum 4, so that the tire under test 5 is only subject to a small load to reduce the influence of its own rolling resistance. Specifically in step S2, install a speed encoder on the tire under test 5 to obtain the rotational speed of the tire under test 5, and compare it with the rotational speed of the drum 4 to judge the adhesion situation between the tire under test 5 and the drum 4, and inversely deduce the minimum test load required to maintain the non-slip state, that is, the critical load. Usually, this critical load is much lower than the test load of the tire under test 5. For example, for a tire under test 5 with a test load of 500 kN, the critical load to keep it in sync with the drum 4 without slipping may be only 10 - 20 kN. Therefore, the influence of the rolling resistance caused by this critical load is relatively small, and it can be estimated according to empirical values to quickly select the critical load. After the tire under test 5 reaches a stable speed, record the reading M1 (unit: kN·m) of the torque sensor 32, the load radius r (unit: m) from the axis center of the tire under test 5 to the outer surface of the drum 4, and the radius R (unit: m) of the drum 4, and calculate the additional loss: f = M1 / r(1 + r / R).

[0063] Step S4 is the step of officially measuring the rolling resistance F of the tire 5 to be tested. After reaching the stable speed, according to the reading M2 (unit: kN·m) of the torque sensor 32, the load radius r (unit: m) from the center of the axis of the tire 5 to be tested to the outer surface of the drum 4, the load radius r (unit: m) of the outer surface of the drum 4, and the additional loss f, when calculating the actual rolling resistance F of the tire 5 to be tested, the influence of the additional loss f is deducted to improve the measurement accuracy. The calculation formula for the rolling resistance F of the tire 5 to be tested is: F = M2 / r(1 + r / R) - f.

[0064] In some embodiments, after the step S1 and before the step S2, the temperature rise of the tire 5 to be tested and the establishment of the stable rolling resistance are carried out, which specifically includes: adjusting the loading device so that the load applied by the tire 5 to be tested to the drum 4 is the test load until the reading of the torque sensor does not change. Ensure that the temperature of the tire 5 to be tested reaches equilibrium to eliminate the influence of temperature changes on the rolling resistance measurement during subsequent experiments.

[0065] In some embodiments, after the step S4, the steps S1 - S4 are repeated. By combining the results of multiple measurements, ensuring that the torque value and the rolling resistance are within a reasonable range, and taking the average of the rolling resistances F of multiple groups of tires 5 to be tested can effectively improve the reliability of the data. If the data fluctuates greatly, the measurement equipment or test conditions can be adjusted, and the above steps S1 - S4 can be repeated to obtain a more accurate rolling resistance value of the tire 5 to be tested.

[0066] According to the disclosure and teachings of the above specification, those skilled in the art to which the present invention pertains can also make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for convenience of description and do not constitute any limitation to the present invention.

Claims

1. A tire rolling resistance test device, characterized in that, Comprising: A loading device, a tooling shaft, a sensing assembly, a drum driving device and a drum; The loading device includes a loader and a loading tooling, and the loading tooling is installed at the power output end of the loader; An installation hole is formed in the loading tooling, the installation hole penetrates through the front and rear end faces of the loading tooling, and the tooling shaft is inserted into the installation hole, and a rotating bearing is arranged between the tooling shaft and the installation hole to realize a rotating connection with the loading tooling; The sensing assembly is arranged at the rear end of the loading tooling, and the sensing assembly includes a fixing frame and a torque sensor, the fixing frame is fixedly connected to the loading tooling, the torque sensor is installed on the fixing frame, and the measuring end of the torque sensor is connected to the rear end of the tooling shaft; An installation position for installing a tire to be measured is provided on the outer periphery of the tooling shaft protruding from the front end of the loading tooling; The drum is installed at the power output end of the drum driving device, and the drum is arranged on one side in the radial direction of the installation position; Wherein, the loading device can drive the loading tooling to slide along the radial direction of the drum, so that the installation position approaches or moves away from the drum, and the drum driving device can drive the drum to rotate.

2. The tire rolling resistance testing device according to claim 1, characterized in that, The loading tooling includes an upper plate, a lower plate and side plates, the upper plate and the lower plate are arranged at intervals up and down, the upper and lower ends of the side plates are respectively fixedly connected to the upper plate and the lower plate, the installation hole is formed in the side plates, the loading tooling is installed at the power output end of the loader through the upper plate, and the fixing frame is fixedly connected to the rear side of the side plates.

3. The tire rolling resistance testing device according to claim 2, characterized in that, The number of the side plates is two, each side plate is provided with an installation hole, the two side plates are arranged at intervals along the axial direction of the tooling shaft, a limiting portion is arranged along the circumferential wall of the installation hole, the limiting portion is fixedly connected to the inner side of the side plate, the limiting portion defines a through hole, the through hole is communicated with the installation hole, a limiting member is sleeved on the tooling shaft, the limiting member is installed outside the installation hole and abuts against the rotating bearing to abut the rotating bearing against the inner side of the limiting portion.

4. The tire rolling resistance testing device according to claim 3, wherein, The two installation holes are respectively defined as: a first installation hole and a second installation hole, the limiting member installed outside the first installation hole is defined as a first limiting member, the limiting member installed outside the second installation hole is defined as a second limiting member, and the first limiting member is fixedly connected to the rear end of the tooling shaft; The tooling shaft protrudes from the front end of the loading tooling and is provided with shaft shoulders at intervals, the shaft shoulders are arranged at intervals at the rear end of the installation position, and the second limiting member is rotatably connected to the tooling shaft and abuts against one side of the shaft shoulder.

5. The tire rolling resistance testing device according to claim 2, characterized in that, The fixing frame includes a transition flange and a plurality of connecting screws, the transition flange is fixedly connected to the rear side of the side plate through the connecting screws, the torque sensor is fixedly connected to the front side of the transition flange, and the torque sensor is arranged at intervals with the connecting screws.

6. The tire rolling resistance testing device according to claim 2, characterized in that, The upper plate is provided with bolt holes, and the loading tooling is fixedly connected to the power output end of the loader through the bolt holes.

7. The tire rolling resistance testing device according to claim 1, characterized in that A tire mounting bearing is sleeved on the mounting position, the tire mounting bearing is connected to the mounting position, and the tire to be tested is mounted on the mounting position through the tire mounting bearing.

8. The tire rolling resistance test device according to claim 1, characterized in that, It further includes a flange assembly. The flange assembly is arranged at an interval from the fixing frame, and the measuring end of the torque sensor is connected to the tooling shaft through the flange assembly.

9. A method for testing the rolling resistance of a tire, using the tire rolling resistance testing device according to any one of claims 1-8, characterized in that, It includes: S1. Complete the installation of the tooling shaft with the loading tooling and the torque sensor. Fix the torque sensor to the loading tooling through the fixing frame. Mount the tire to be tested on the mounting position. The drum driving device drives the drum to rotate at a set test speed. S2. Select a test load within the specified test load range. Adjust the loading device so that the load applied by the tire to be tested to the drum is the test load. When ensuring that the rotation speed of the tire to be tested is the same as that of the drum, select the minimum value of the test load through experiments and define it as the critical load. S3. Adjust the loading device so that the load applied by the tire to be tested to the drum is the critical load. After the tire to be tested reaches a stable speed, record the reading M1 of the torque sensor at this time. According to M1, the load radius r from the center of the axis of the tire to be tested to the outer surface of the drum, and the radius R of the drum, calculate the additional loss f. The calculation formula for the additional loss f is: f = M1 / r(1 + r / R). S4. Adjust the loading device so that the load applied by the tire to be tested to the drum is the set test load. After the tire to be tested reaches a stable speed, record the reading M2 of the torque sensor, and calculate the rolling resistance F of the tire to be tested according to M2, the load radius r from the center of the tire to be tested to the outer surface of the drum, the radius R of the drum, and the additional loss f. The calculation formula for the rolling resistance F of the tire to be tested is: F = M2 / r(1 + r / R) - f.

10. The tire rolling resistance test method according to claim 9, wherein, It includes: After step S1 and before step S2, adjust the loading device so that the load applied by the tire to be tested to the drum is the test load until the reading of the torque sensor does not change.

Images