Loading device and loop accelerated loading test system

Abstract

The invention provides a loading device and a loop accelerated loading test system, and belongs to the technical field of pavement performance tests.The loading device comprises a gantry frame, a bearing frame, a uniform loading beam and a loading vehicle; rail wheel sets are arranged on the two sides of the gantry frame respectively, and the rail wheel sets on the two sides are used for vertically clamping and rolling rails on the two sides of a test loop respectively. The bearing frame is slidably connected to the middle of the gantry frame in the road width direction of the test loop, and pressure sensors are arranged between the two sides of the bearing frame and the gantry frame. One side of the uniform load beam is hinged to the bearing frame, and the other side of the uniform load beam is connected with the bearing frame through a loading cylinder; a connecting beam is arranged in the middle of the loading vehicle and hinged to the middle of the uniform load beam. Wherein the loading cylinder is provided with an adjusting piece used for flexibly adjusting the pushing force of the loading cylinder, and the pressure sensor is used for detecting the lateral force transmitted to the bearing frame when the loading vehicle turns. According to the loading device provided by the invention, the comprehensiveness of loop accelerated loading test data can be improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of road surface performance test, and particularly relates to a loading device and a loop track accelerated loading test system. BACKGROUND

[0002] The accelerated loading test is used for comprehensively simulating the actual service conditions of road surface materials and structures under special regional environments, and is very important for the research of new road surface structures, new materials and new technologies. The accelerated loading test project mainly includes two modes of straight track accelerated loading test and loop track accelerated loading test.

[0003] For the loop track accelerated loading test, the loop track structure is usually in the form of a circular track composed of two curved tracks and two straight tracks, so that the continuity of the accelerated loading test can be realized. However, due to the current loop track being a horizontal road surface, the loop track accelerated loading test lacks effective simulation conditions for the actual working conditions of vehicles on uphill and downhill tracks. In addition, the influence of road surface performance on sideslip during the turning of the vehicle cannot be effectively tested. Therefore, there is still a great space for improvement in the data comprehensiveness of the loop track accelerated loading test, and a more perfect test scheme needs to be developed. SUMMARY

[0004] The embodiments of the application provide a loading device and a loop track accelerated loading test system, which aims to improve the comprehensiveness of the data of the loop track accelerated loading test.

[0005] To achieve the above-mentioned purpose, the technical scheme adopted by the application is as follows: in a first aspect, a loading device is provided, comprising: A gantry frame, two sides of which are respectively provided with rail wheel sets, and the rail wheel sets on the two sides are respectively used for clamping and rolling the tracks on the two sides of the test loop track; A bearing frame, which is slidingly connected to the middle part of the gantry frame along the road surface width direction of the test loop track, and pressure sensors are arranged between the two sides of the bearing frame and the gantry frame; An equal load beam, which is hingedly connected to one side of the bearing frame and connected to the bearing frame through a loading cylinder on the other side; A loading vehicle, the middle part of which is provided with a connecting beam, and the connecting beam is hingedly connected to the middle part of the equal load beam; The loading cylinder is used to push the equal load beam to make the loading vehicle apply a load to the road surface of the test loop track, and the loading cylinder has an adjusting part for flexibly adjusting the pushing force of the loading cylinder, and the pressure sensor is used to detect the lateral force transmitted to the bearing frame when the loading vehicle turns.

[0006] In combination with the first aspect, in a possible implementation manner, the loading cylinder comprises: A cylinder body, which is hingedly connected to the outside of the bearing frame and provided with an adjusting part; The pressure regulating piston is slidably connected in the cylinder and is in transmission connection with the adjusting member, the pressure regulating piston separates the inside of the cylinder into a sealed medium cavity, and the medium cavity is filled with fluid; The loading piston is slidably connected in the medium cavity, the loading piston has a loading rod downwardly sealed through the cylinder and hinged to the load equalizing beam, and the loading piston has a damping hole penetrating upwardly and downwardly; The adjusting member is used to drive the pressure regulating piston to move upwardly and downwardly to adjust the volume of the medium cavity, and the damping hole is used to balance the fluid pressure on both sides of the loading piston.

[0007] In some embodiments, the loading piston separates the medium cavity into a rodless cavity and a rod cavity upwardly and downwardly; the rodless cavity is provided with a first high-pressure air bag, and the rod cavity is provided with a second high-pressure air bag.

[0008] For example, the loading piston has a liquid flow hole penetrating upwardly and downwardly, and the liquid flow hole is provided with a liquid flow valve; wherein the liquid flow valve is opened when the fluid pressure difference on both sides of the loading piston is greater than a set threshold value, and is closed when the fluid pressure difference on both sides of the loading piston is less than or equal to the set threshold value.

[0009] For example, the liquid flow valve comprises: A valve body embedded in the liquid flow hole, a valve hole penetrating the center of the valve body in the axial direction is provided, the valve hole comprises a small-diameter section and two large-diameter sections respectively located at both ends of the small-diameter section; A valve core slidably connected to the small-diameter section, the center of the valve core is provided with a through hole, and the middle part of the outer periphery of the valve core is provided with an annular groove, the annular groove is in communication with the through hole through a radial hole; Two valve rods are respectively fixedly connected in the two large-diameter sections and are respectively inserted into the two ends of the through hole, and the two valve rods are respectively provided with elastic members abutting against the valve core; Wherein, when the fluid pressure difference on both sides of the loading piston is greater than the set threshold value, the valve core slides to the low-pressure side to an open state based on the pressure difference and overcoming the elastic force of the elastic member; when the fluid pressure difference on both sides of the loading piston is equal to or less than the set threshold value, the valve core is reset under the elastic force of the elastic member and remains in a closed state.

[0010] For example, the adjusting member comprises: A rotary driving member fixedly connected to the outer wall of the cylinder; A rotating sleeve rotationally connected to the center of the top wall of the cylinder; A driving rod having one end connected to the pressure regulating piston and the other end penetrating through the rotating sleeve and in transmission connection with the output end of the rotary driving member, and the driving rod is in screw connection with the rotating sleeve.

[0011] With the first aspect, in a possible implementation manner, the front and rear ends of the portal frame are oppositely provided with sliding grooves, and the front and rear ends of the bearing frame are correspondingly and slidingly connected to the two sliding grooves respectively; two pushing pieces are oppositely arranged in each sliding groove, and the two pushing pieces are located at the two sides of the bearing frame respectively, and a pressure sensor is arranged between each pushing piece and the bearing frame.

[0012] In some embodiments, the pushing piece is a telescopic cylinder, the output end of the telescopic cylinder is provided with an elastic support, and the pressure sensor is arranged between the elastic support and the side wall of the bearing frame.

[0013] For example, the end of the bearing frame extending into the sliding groove is provided with a roller on each of the upper and lower sides, and each roller is rolled on the groove wall of the sliding groove.

[0014] In some possible implementation manners, the loading device further comprises a controller, the controller is electrically connected to the pressure sensor, the adjusting piece and the loading vehicle respectively, and the controller is wirelessly connected to the remote industrial computer.

[0015] The loading device provided by the application has the following beneficial effects: compared with the prior art, the loading device uses the track wheels on the two sides of the portal frame to clamp and roll on the tracks on the two sides of the test loop, which not only ensures the stability of the movement of the portal frame along the test loop, but also ensures that the loading force applied to the loading vehicle is sufficient and stable by means of the reaction force provided by the tracks.

[0016] The side of the uniform load beam is hinged to the loading beam, and when loading is required, the other side of the uniform load beam is only pushed by the loading cylinder, so that the uniform load beam swings down and transmits the load to the loading vehicle through the hinge point in the middle of the uniform load beam, so as to apply a load to the road surface of the test loop, which can avoid the movement jamming problem of the traditional overall lifting loading method, and can avoid the uneven load distribution on the two sides of the loading vehicle due to the use of the central hinge point to transmit the load, thereby improving the test accuracy.

[0017] During the test, the pushing force of the loading cylinder can be adjusted by the adjusting piece, so as to simulate the load change on the road surface when the loading vehicle goes up and down the slope, thereby improving the data acquisition comprehensiveness of the acceleration loading test, and the adjustment of the pushing force is flexible, which can avoid the impact problem caused by direct adjustment, thereby ensuring the service life of the loading cylinder.

[0018] In addition, when the loading vehicle passes through the curve, the lateral force transmitted by the loading vehicle to the bearing frame can be detected by the pressure sensor, so as to judge the side slip tendency data between the loading vehicle and the road surface through the lateral force, thereby further improving the data comprehensiveness of the road surface performance test.

[0019] In a second aspect, the embodiment of the present application further provides a test system for a circular track accelerated loading, which comprises a test circular track, a track arranged along the test circular track, and the loading device.

[0020] The test system for the circular track accelerated loading has the advantages that, compared with the prior art, the test system for the circular track accelerated loading adopts the loading device, can feed back the influence data of the road surface performance on the sideslip of the loading vehicle in the process of passing the bend through the detection value of the pressure sensor, and can simulate the scene of the uphill and downhill of the loading vehicle by flexibly adjusting the jacking force of the loading cylinder by the adjusting member, so that the data acquisition comprehensiveness of the accelerated loading test is further improved. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 A perspective structural schematic view of the loading device provided by the embodiment of the present application; Figure 2 A front view structural schematic view of the loading device provided by the embodiment of the present application; Figure 3 A connecting structural schematic view of the carrying frame and the gantry frame in the embodiment of the present application; Figure 4 A structural schematic view along the track arranged along the test circular track in the embodiment of the present application; Figure 3 A sectional view structural schematic view along the line A-A in the embodiment of the present application; Figure 5 A sectional view structural schematic view of the loading cylinder adopted by the embodiment of the present application; Figure 6 A sectional view structural schematic view of the liquid flow valve in the closed state adopted by the embodiment of the present application; Figure 7 A sectional view structural schematic view of the liquid flow valve in the open state adopted by the embodiment of the present application.

[0022] In the figure: 10, gantry frame; 11, track wheel set; 12, sliding groove; 121, jacking member; 122, elastic support member; 20, carrying frame; 21, rolling row; 30, pressure sensor; 40, load sharing beam; 50, loading cylinder; 51, cylinder body; 511, medium cavity; 512, rodless cavity; 5121, first high-pressure air bag; 5122, first inflation hole; 5123, first air valve; 513, rod cavity; 5131, second high-pressure air bag; 5132, second inflation hole; 5133, second air valve; 52, pressure regulating piston; 53, loading piston; 531, loading rod; 532, damping hole; 60, loading vehicle; 61, connecting beam; 70, adjusting member; 71, rotary driving member; 72, rotating sleeve; 73, driving rod; 80, test circular track; 81, track; 90, liquid flow valve; 91, valve body; 911, valve hole; 9111, small-diameter section; 9112, large-diameter section; 92, valve core; 921, through hole; 922, annular groove; 923, radial hole; 924, valve rod; 925, elastic member. DETAILED DESCRIPTION

[0023] In order to make the technical problems to be solved by the present application, technical solutions and beneficial effects clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not intended to limit the present application.

[0024] It should be noted that when an element is referred to as being "disposed on", "connected to" or "coupled to" another element, it can be directly on, connected or coupled to the other element or indirectly on, connected or coupled to the other element. It should be understood that the terms "on", "under", "front", "back", "top", "bottom", "inner", "outer", and the like, indicate the orientation or positional relationship based on the drawings shown, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. The terms "first", "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or several of the features. In the description of the present application, the meaning of "a plurality of", "several" is two or more, unless otherwise explicitly specified.

[0025] It should be understood that for the track acceleration loading test, the test track is constructed according to the design material, pavement structure and paving process on the test site, and the test track is similar to the traditional runway structure composed of two straight tracks and two curves. The traditional acceleration loading test mainly obtains test data by applying load on the straight track, and the curve mainly ensures the continuity of the test process.

[0026] The more pavement performance parameters obtained by the acceleration loading test, the more beneficial it is for the research of pavement structure, material and process innovation and improvement, and therefore the comprehensiveness of the test data obtained is very important. The traditional acceleration loading test is usually limited to simulating the working condition of the vehicle driving straight on the horizontal road, and different parameters are obtained by changing the pavement temperature, humidity and other conditions of the test track based on this working condition. However, the actual pavement often has many ups and downs, curves and other conditions. Whether it has the same performance as the horizontal straight track under these pavement conditions cannot obtain accurate data verification, which is the main problem to be solved by the present application.

[0027] Please refer to Figures 1 to 7The loading device provided by the application is described as follows. The loading device comprises a portal frame 10, a bearing frame 20, an equal load beam 40 and a loading vehicle 60. The portal frame 10 is provided with rail wheel sets 11 on both sides, and the rail wheel sets 11 on both sides are used for clamping and rolling the tracks 81 on both sides of a test loop 80. The bearing frame 20 is slidably connected to the middle part of the portal frame 10 along the road width direction of the test loop 80, and pressure sensors 30 are arranged between the bearing frame 20 and the portal frame 10 on both sides. One side of the equal load beam 40 is hingedly connected to the bearing frame 20, and the other side is connected to the bearing frame 20 through a loading cylinder 50. The middle part of the loading vehicle 60 is provided with a connecting beam 61, and the connecting beam 61 is hingedly connected to the middle part of the equal load beam 40.

[0028] The loading cylinder 50 is used for pushing the equal load beam 40 to apply a load to the road surface of the test loop 80 by the loading vehicle 60, and the loading cylinder 50 has an adjusting part 70 for flexibly adjusting the pushing force. The pressure sensors 30 are used for detecting the lateral force transmitted to the bearing frame 20 when the loading vehicle 60 passes through a curve.

[0029] It should be noted that the rail wheel sets 11 on both sides of the portal frame 10 each comprise at least one rail wheel rolling on the upper rail surface of the track 81 and at least two rail wheels rolling on the lower rail surface of the track 81, so as to form upper and lower clamping of the track 81.

[0030] The loading vehicle 60 can be a single-axle vehicle or a multi-axle vehicle based on the actual wheel set of a vehicle. The wheel shafts can be driven by motors, and the motors can be powered by contacting the cables arranged along the track 81 through the brushes arranged on the portal frame 10. This driving and power supply mode of the motor is a common technical means in the art, and will not be described in detail here.

[0031] The bearing frame 20 is slidably connected to the portal frame 10, so that the bearing frame 20 has the freedom of sliding along the road width direction. On this basis, the pressure sensors 30 are arranged between the bearing frame 20 and the portal frame 10 on both sides. When the centrifugal force generated based on the circular motion of the loading vehicle 60 exceeds the friction force between the tire and the road surface, the loading vehicle 60 transmits the lateral force in the road width direction to the bearing frame 20 through the equal load beam 40. The pressure sensors 30 are used for detecting the size of the lateral force. Since the speed V of the loading vehicle 60, the radius R of the curve and the load N applied to the road surface by the loading vehicle 60 are known, the size of the centrifugal force F can be calculated as MV 2F = MR / g, wherein, M = N / g, g is the acceleration of gravity. The difference between the centrifugal force F and the detection value of the pressure sensor 30 is the side slip friction force f between the tire of the loading vehicle 60 and the road surface, and on this basis, the ratio of the side slip friction force f to the load N applied by the loading vehicle 60 to the road surface is the road surface friction coefficient, which is related to the side slip phenomenon during vehicle driving, but is not equal to the straight line friction coefficient between the road surface and the tire under the normal straight line driving condition of the loading vehicle 60.

[0032] When the vehicle enters the uphill road surface from the horizontal road surface, the gravity center of the vehicle shifts to the rear axle, so although the total load of the vehicle on the road surface slightly decreases, the load of the rear axle of the vehicle on the road surface increases, and the load of the front axle certainly decreases. Similarly, when the vehicle enters the downhill road surface, the gravity center of the vehicle shifts forward, so the load of the rear axle of the vehicle on the road surface decreases, and the load of the front axle increases. Therefore, in the embodiment, the adjusting member 70 is arranged to adjust the thrust force of the loading cylinder 50, so that the load of the loading vehicle 60 on the test road surface changes, thereby simulating the working condition of the vehicle on the uphill and downhill road.

[0033] The uniform load beam 40 is hinged at the middle part to the bearing frame 20, so that when the loading cylinder 50 pushes the bearing frame 20 to swing, the load is always transmitted to the uniform load beam 40 through the hinge point and is evenly distributed to the wheels on both sides of the loading vehicle 60, thereby avoiding the uneven load on both sides of the loading vehicle 60.

[0034] Compared with the prior art, the loading device provided in the embodiment uses the gantry frame 10 as the installation base, which can cross above the road surface of the test loop 80, thereby providing sufficient installation space and stable force for the loading vehicle 60. From the connection structure, the track wheels 11 on both sides of the gantry frame 10 can respectively clamp and roll the tracks 81 on both sides of the test loop 80, thereby not only ensuring the stability of the movement of the gantry frame 10 along the test loop 80, but also ensuring that the loading force transmitted to the loading vehicle 60 is sufficient and stable by means of the reaction force provided by the tracks 81.

[0035] One side of the uniform load beam 40 is hinged to the loading beam, and when loading is needed, the other side of the uniform load beam 40 is only pushed by the loading cylinder 50, so that the uniform load beam 40 swings downward and transmits the load to the loading vehicle 60 through the hinge point in the middle part, thereby enabling the loading vehicle 60 to apply a load to the road surface of the test loop 80. On the one hand, this can avoid the movement jamming problem of the traditional overall lifting loading mode, and on the other hand, since the hinge point is arranged in the middle part to transmit the load, the uneven load distribution on both sides of the loading vehicle 60 can be avoided, thereby improving the test accuracy.

[0036] When the test is carried out, the thrust degree of the loading cylinder 50 can be adjusted by the adjusting member 70, so as to simulate the load change on the road surface when the loading vehicle 60 goes up and down the slope, so as to improve the data acquisition comprehensiveness of the acceleration loading test, and the adjustment of the thrust degree is flexible adjustment, so as to avoid the impact problem caused by direct adjustment, so as to ensure the service life of the loading cylinder 50.

[0037] In addition, when the loading vehicle 60 passes through the curve, the lateral force of the loading vehicle 60 transmitted to the bearing frame 20 can be detected by the pressure sensor 30, so as to judge the side slip tendency data between the loading vehicle 60 and the road surface through the lateral force, and further improve the data comprehensiveness of the road surface performance test.

[0038] In some embodiments, referring to Figure 5 , the loading cylinder 50 comprises a cylinder body 51, a pressure regulating piston 52 and a loading piston 53; the cylinder body 51 is hinged to the outside of the bearing frame 20 and is provided with an adjusting member 70; the pressure regulating piston 52 is slidingly connected in the cylinder body 51 and is drivingly connected with the adjusting member 70, and the pressure regulating piston 52 separates the inside of the cylinder body 51 into a sealed medium cavity 511, and the medium cavity 511 is filled with fluid; the loading piston 53 is slidingly connected in the medium cavity 511, and the loading piston 53 has a loading rod 531 sealingly penetrating downwardly out of the cylinder body 51 and hinged to the uniform load beam 40, and the loading piston 53 has a damping hole 532 penetrating upwardly and downwardly; wherein the adjusting member 70 is used to drive the pressure regulating piston 52 to move upwardly and downwardly to adjust the volume of the medium cavity 511, and the damping hole 532 is used to balance the fluid pressure on both sides of the loading piston 53.

[0039] The cylinder body 51 is connected to the bearing frame 20 in a hinged manner, which can ensure that the cylinder body 51 can adaptively swing when the loading cylinder 50 pushes the uniform load beam 40, so as to avoid that the cylinder body 51 and the loading cylinder 50 bear additional bending moment during the loading process, thereby causing sealing damage or other damage. It should be understood that, since the difference in contact area of the piston on both sides with the fluid is the cross-sectional area of the loading cylinder 50, when the fluid pressure on both sides of the loading piston 53 is balanced, the load applied to the uniform load beam 40 by the loading piston 53 through the loading rod 531 is the product of the fluid pressure and the cross-sectional area of the loading rod 531.

[0040] When it is necessary to increase the output load, the adjusting member 70 drives the pressure regulating piston 52 to move downwardly, so as to reduce the volume of the medium cavity 511 and increase the fluid pressure on the upper side of the loading piston 53, thereby increasing the downward thrust degree of the loading piston 53, and at this time, the load change on the road surface by the rear axle of the vehicle when going uphill can be simulated by the loading vehicle 60; when it is necessary to reduce the output load, the adjusting member 70 drives the pressure regulating piston 52 to move upwardly, at this time, the volume of the medium cavity 511 increases, and the fluid pressure on the upper side of the loading piston 53 decreases, so as to reduce the downward thrust degree of the loading piston 53, thereby simulating the load change on the road surface by the rear axle of the vehicle when going downhill.

[0041] On the basis of the above, by setting the damping hole 532 on the loading piston 53, the cavity spaces on both sides of the loading piston 53 are communicated, so that when the pressure regulating piston 52 descends, the fluid can flow from the upper side to the lower side of the loading piston 53 through the damping hole 532 until the fluid pressures on both sides of the loading piston 53 are consistent, thereby on the one hand buffering the impact of the fluid on the loading piston 53 and the cylinder body 51 when the pressure regulating piston 52 descends, realizing flexible adjustment of the thrust degree, and on the other hand simulating a more realistic working condition of the vehicle entering the uphill road surface from the horizontal road surface, taking the rear axle load of the vehicle as an example, the principle is as follows: As the actual process of the vehicle climbing uphill, the load of the rear axle of the vehicle on the road surface increases sharply at the moment of entering the uphill road surface from the horizontal road surface, and then gradually decreases to a stable state. The load of the rear axle on the road surface in the stable state is still higher than that in the working condition of driving on the horizontal road surface.

[0042] According to the above actual working condition, since it is a slow process for the fluid to pass through the damping hole 532 to balance the fluid pressures on both sides of the loading piston 53, the fluid pressure on the upper side of the loading piston 53 is higher than that on the lower side of the loading piston 53 at the moment when the adjusting member 70 drives the pressure regulating piston 52 to descend, so that the thrust degree of the loading piston 53 increases instantaneously, thereby simulating the moment when the vehicle enters the uphill road surface. With the gradual passage of the fluid through the damping hole 532 to balance the fluid pressures on both sides of the loading piston 53, the output thrust degree of the loading piston 53 also gradually decreases until it reaches a stable state, thereby simulating the working condition of the vehicle stably driving on the uphill road surface.

[0043] Similarly, as the actual process of the vehicle descending, the load of the rear axle of the vehicle on the road surface decreases sharply at the moment of entering the downhill road surface from the horizontal road surface, and then gradually increases to a stable state. Corresponding to this process, the fluid pressure on the upper side of the loading piston 53 decreases at the moment when the pressure regulating piston 52 ascends, and at this time the fluid pressure on the lower side of the loading piston 53 has not changed, so that the output load decreases rapidly. Then, with the continuous passage of the fluid through the damping hole 532 into the upper cavity space of the loading piston 53 under the action of the pressure difference, the output load gradually increases, and when the fluid pressures on both sides of the loading piston 53 are balanced, the output load also tends to be stable.

[0044] In some possible implementation manners, please refer to Figure 5 The loading piston 53 divides the medium cavity 511 into a rodless cavity 512 and a rod cavity 513; the rodless cavity 512 is provided with a first high-pressure air bag 5121, and the rod cavity 513 is provided with a second high-pressure air bag 5131.

[0045] As the loading cylinder 50 extends to the lower side of the loading piston 53 and penetrates the cylinder body 51, the upper side of the loading piston 53 is a rodless cavity 512, and the lower side of the loading piston 53 forms a rod cavity 513 based on the loading rod 531. The contact area difference between the fluid in the rodless cavity 512 and the rod cavity 513 makes the loading piston 53 output a thrust force.

[0046] Here, the functions of the first high-pressure air bag 5121 and the second high-pressure air bag 5131 are to consider that the fluid filled in the medium cavity 511 is a liquid such as hydraulic oil, which has a relatively small compression ratio, and the first high-pressure air bag 5121 and the second high-pressure air bag 5131 are filled with a gas such as air or inert gas, which has a relatively high compression ratio.

[0047] When the pressure regulating piston 52 descends, the thrust force output by the loading piston 53 is instantaneously increased due to the instantaneous increase in the fluid pressure in the rodless cavity 512, and at the same time, the first high-pressure air bag 5121 is also compressed, thereby on the one hand buffering the fluid impact, and on the other hand, when the fluid in the rodless cavity 512 gradually enters the rod cavity 513 through the damping hole 532, the first high-pressure air bag 5121 plays a role in expanding and driving the fluid, thereby improving the balancing efficiency of the fluid pressure.

[0048] When the pressure regulating piston 52 ascends, the thrust force output by the loading piston 53 is instantaneously decreased due to the instantaneous decrease in the fluid pressure in the rodless cavity 512, and at the same time, the first high-pressure air bag 5121 is also expanded, thereby forming a state in which the air pressure of the second high-pressure air bag 5131 is higher than that of the first high-pressure air bag 5121, so that the second high-pressure air bag 5131 extrudes the fluid from the rod cavity 513 to the rodless cavity 512 through the damping hole 532, and promotes the fluid pressure in the rod cavity 513 and the rodless cavity 512 to reach balance as soon as possible.

[0049] By setting the first high-pressure air bag and the second high-pressure air bag 5131, the rodless cavity 512 and the rod cavity 513 can both be filled with a mixed medium of gas and liquid, thereby increasing the medium compression ratio, and thereby being able to reduce the rigid impact on the basis of truly simulating the uphill and downhill working conditions of the vehicle, and realizing the flexible adjustment of the thrust degree of the loading cylinder 50.

[0050] Specifically, in combination with Figures 5 to 7 It is understood that in the embodiment, the loading piston 53 has a liquid flow hole penetrating from top to bottom, and a liquid flow valve 90 is arranged in the liquid flow hole; wherein the liquid flow valve 90 is opened when the fluid pressure difference on both sides of the loading piston 53 is greater than a set threshold, and is closed when the fluid pressure difference on both sides of the loading piston 53 is less than or equal to the set threshold.

[0051] If the damping hole 532 is too large, the damping effect will be lost, which will affect the authenticity of the load instantaneous change when the vehicle enters the uphill or downhill road from the horizontal road. However, since the damping hole 532 restricts the flow speed of the fluid between the rod cavity 513 and the rodless cavity 512, the process of restoring stability after the load changes sharply is relatively slow. However, in the actual working condition, the load on the road will soon enter a stable state after the vehicle as a whole enters the uphill or downhill road. Therefore, in this embodiment, a liquid flow valve 90 is arranged on the loading piston 53 to improve the speed of restoring balance after the fluid pressure of the rod cavity 513 and the rodless cavity 512 changes instantaneously. The principle is as follows: The liquid flow valve 90 is a normally closed valve that can be opened in both directions. Its opening and closing state depends on the fluid pressure difference between the rod cavity 513 and the rodless cavity 512. When the adjusting part 70 drives the pressure regulating piston 52 to move downward, the fluid pressure in the rodless cavity 512 instantaneously increases, and the thrust of the loading piston 53 instantaneously increases. When the fluid pressure in the rodless cavity 512 is higher than the fluid pressure in the rod cavity 513, and the difference between the two reaches a set threshold, the liquid flow valve 90 opens. At this time, the fluid in the rodless cavity 512 can flow to the rod cavity 513 through the liquid flow valve 90 and the damping hole 532, thereby improving the balance speed of the fluid pressure of the rod cavity 513 and the rodless cavity 512. Conversely, when the adjusting part 70 drives the pressure regulating piston 52 to move upward, the fluid pressure in the rodless cavity 512 instantaneously decreases, and the thrust of the loading piston 53 instantaneously decreases. When the fluid pressure in the rodless cavity 512 is lower than the fluid pressure in the rod cavity 513, and the difference between the two reaches a set threshold, the liquid flow valve 90 opens. At this time, the fluid in the rod cavity 513 flows to the rodless cavity 512 through the liquid flow valve 90 and the damping hole 532 to balance the fluid pressure. Compared with the way of simply setting the damping hole 532, the liquid flow valve 90 can improve the fluid pressure balance efficiency.

[0052] Optionally, the structure of the liquid flow valve 90 in this embodiment is as shown in Figure 6 and Figure 7 The liquid flow valve 90 includes a valve body 91, a valve core 92, and two valve rods 924. The valve body 91 is embedded in the liquid flow hole. The center of the valve body 91 is provided with a valve hole 911 in the axial direction. The valve hole 911 includes a small-diameter section 9111 and two large-diameter sections 9112 located at both ends of the small-diameter section 9111. The valve core 92 is slidingly connected to the small-diameter section 9111. The center of the valve core 92 is provided with a through hole 921. The outer periphery of the valve core 92 is provided with a ring groove 922. The ring groove 922 is in communication with the through hole 921 through a radial hole 923. The two valve rods 924 are fixedly connected to the two large-diameter sections 9112, respectively, and are correspondingly inserted into the two ends of the through hole 921, respectively. The two valve rods 924 are respectively provided with elastic members 925 abutting against the valve core 92.

[0053] Specifically, when the fluid pressure difference across the loading piston 53 is greater than a set threshold, the valve core 92 slides to the low-pressure side to the open state based on the pressure difference, overcoming the elastic force of the elastic element 925; when the fluid pressure difference across the loading piston 53 is equal to or less than the set threshold, the valve core 92 resets under the action of the elastic force of the elastic element 925 and remains in the closed state.

[0054] When the fluid pressure difference across the valve core 92 is equal to or lower than the set threshold, the axial force generated on the valve core 92 based on the fluid pressure difference is insufficient to overcome the elastic force of the elastic element 925, such as a spring. Therefore, the valve core 92 is in the neutral position and remains in the plugged state with the two valve stems 924, and the fluid cannot enter the through hole 921. When the fluid pressure difference is higher than the set threshold, the difference in fluid squeezing force on both sides of the valve core 92 is higher than the elastic force applied to it by the elastic element 925. Therefore, the valve core 92 will move axially toward the side with lower fluid pressure, thereby forming an open state in which the large-diameter section 9112 on the low-pressure side is connected to the annular groove 922 and the valve stem 924 on the high-pressure side is withdrawn from the through hole 921. At this time, the fluid on the high-pressure side enters the through hole 921 and enters the annular groove 922 through the radial hole 923 from the through hole 921, and then flows into the large-diameter section 9112 on the low-pressure side.

[0055] As the fluid continues to flow from the high-pressure side to the low-pressure side, the fluid pressure difference on both sides of the loading piston 53 gradually decreases. When the fluid pressure difference decreases to be equal to or less than the set threshold, the force exerted by the elastic element 925 on the valve core 92 is greater than the force exerted by the pressure difference, thereby causing the valve core 92 to slide to the middle position and re-form the closed state where the through hole 921 and the valve stems 924 on both sides are inserted.

[0056] This design utilizes the insertion and engagement of two valve stems 924 with the through hole 921 and the elastic force of the elastic element 925 on the valve core 92 to achieve switching based on changes in fluid pressure difference. This not only enables bidirectional opening but also features a simple, compact structure and high stability.

[0057] For example, such as Figure 5 As shown, the adjusting component 70 includes a rotary drive component 71, a rotating sleeve 72, and a drive rod 73; the rotary drive component 71 is fixedly connected to the outer wall of the cylinder body 51; the rotating sleeve 72 is rotatably connected to the center of the top wall of the cylinder body 51; one end of the drive rod 73 is connected to the pressure regulating piston 52, and the other end passes through the rotating sleeve 72 and is connected to the output end of the rotary drive component 71, and the drive rod 73 is threadedly engaged with the rotating sleeve 72.

[0058] The rotating driving member 71 can be a driving motor such as a servo motor or a step motor capable of bidirectional rotation. The transmission connection mode between the rotating driving member 71 and the rotating sleeve 72 can be gear transmission. The rotating driving member 71 drives the rotating sleeve 72 to rotate, which drives the driving rod 73 to move axially by virtue of the threaded cooperation between the rotating sleeve 72 and the driving rod 73, thereby driving the driving rod 73 to move axially and driving the pressure regulating piston 52 to slide up and down in the cylinder body 51. The driving mode is stable and efficient. The amount of axial movement of the driving rod 73 can be controlled by controlling the rotation angle of the driving motor, thereby achieving accurate regulation of the movement amount of the pressure regulating piston 52 and improving the regulation accuracy of the output thrust degree of the loading cylinder 50.

[0059] As shown in Figure 5 , the fluid pressure in the medium cavity 511 under normal conditions is determined by the air pressure of the first high-pressure air bag 5121 and the second high-pressure air bag 5131. Therefore, the fluid pressure can be finely adjusted (it is difficult to adjust greatly) by changing the inflation amount of the first high-pressure air bag 5121 and the second high-pressure air bag 5131. In this embodiment, the first high-pressure air bag 5121 is connected to the top of the rodless cavity 512, i.e., the pressure regulating piston 52. The center of the driving rod 73 and the pressure regulating piston 52 is provided with a first inflation hole 5122 in communication with the first high-pressure air bag 5121. The first inflation hole 5122 is provided with a first air valve 5123. The second high-pressure air bag 5131 is connected to the bottom of the rod cavity 513. The bottom wall of the cylinder body 51 is provided with a second inflation hole 5132 in communication with the second high-pressure air bag 5131. The second inflation hole 5132 is provided with a second air valve 5133.

[0060] In some embodiments, referring to Figure 3 and Figure 4 , the gantry frame 10 is provided with a sliding groove 12 at each of the front and rear ends. The front and rear ends of the bearing frame 20 are respectively and correspondingly connected to the two sliding grooves 12. Each sliding groove 12 is provided with two pushing members 121 opposite to each other. The two pushing members 121 are respectively located at the two sides of the bearing frame 20. A pressure sensor 30 is arranged between each pushing member 121 and the bearing frame 20.

[0061] The sliding connection of the two ends of the bearing frame 20 to one of the sliding grooves 12 can ensure the stability of the connection of the bearing frame 20. After the pushing members 121 cooperate to constrain the sliding of the bearing frame 20, the lateral force acting on the gantry frame 10 by the loading beam of the loading vehicle 60 when the loading vehicle 60 passes through a curve can be detected by the corresponding pressure sensor 30. The pushing member 121 can be an extension cylinder or an electric push rod. The pushing action of the pushing member 121 can drive the bearing frame 20 to slide in the sliding groove 12, thereby adjusting the position of the loading vehicle 60 in the width direction of the road surface, meeting the loading test requirements of different positions of the road surface.

[0062] For example, as shown in Figure 4As shown, the above-mentioned pushing piece 121 is a telescopic cylinder, the output end of the telescopic cylinder is provided with an elastic support 122, and the pressure sensor 30 is arranged between the elastic support 122 and the side wall of the bearing frame 20.

[0063] Here, the elastic support 122 can be a single-layer or multi-layer stacked disc spring. By arranging the elastic support 122, the pushing piece 121 can form a transverse elastic constraint on the bearing frame 20, so that when the loading vehicle 60 slides due to the centrifugal force exceeding the lateral friction force during the cornering process, the bearing frame 20 can obtain a corresponding transverse displacement, thereby calculating the sliding friction force between the tire of the loading vehicle 60 and the road surface according to the detection value of the pressure sensor 30. Compared with the rigid constraint on the bearing frame 20 which can only obtain the lateral static friction, the lateral sliding friction force is obtained by simulating the actual sliding condition, thereby facilitating the in-depth study of the relationship between the road surface performance and the vehicle cornering stability, and improving the data acquisition comprehensiveness of the acceleration loading test.

[0064] It should be noted that since the friction force between the bearing frame 20 and the chute 12 has a great influence on the lateral force test data, in order to improve the data accuracy, as shown in the embodiment, the end of the bearing frame 20 extending into the chute 12 is provided with a roller 21 on the upper side and the lower side. Figure 4 It should be noted that since the friction force between the bearing frame 20 and the chute 12 has a great influence on the lateral force test data, in order to improve the data accuracy, as shown in the embodiment, the end of the bearing frame 20 extending into the chute 12 is provided with a roller 21 on the upper side and the lower side.

[0065] It should be understood that on the basis of the above-mentioned embodiment, the loading device further comprises a controller, the controller is electrically connected with the pressure sensor 30, the rotating driving piece 71, the loading vehicle 60 and the pushing piece 121 respectively, and the controller is wirelessly connected with a remote industrial computer.

[0066] It should be noted that the remote industrial computer can be an industrial computer arranged in a control room outside the test site. The controller and the remote industrial computer can realize signal transmission through a wireless transmission module. These are very mature existing technical means, and will not be described in detail here.

[0067] The pressure sensor 30 can feed back the detection data to the controller in real time, and the controller can send the data to the remote industrial computer in a wireless transmission mode (for the purpose of enabling the operator to master the lateral force data of the curve), and the operator can send instructions to the controller through the remote industrial computer, and the controller controls the rotary driving member 71, the loading vehicle 60 and the pushing member 121 to perform corresponding actions based on the control instructions, and the control instructions should at least include the speed of the loading vehicle 60, the rotation angle of the rotary driving member 71 (for the purpose of adjusting the sliding amount of the pressure regulating piston 52, and then controlling the load size and variation law), and the extension amount of the pushing member 121 (for the purpose of controlling the position of the loading vehicle 60 acting on the road in the width direction).

[0068] Based on the same inventive concept, in combination with Figures 1 to 7 It should be understood that the embodiments of the present application also provide a loop acceleration loading test system, which comprises a test loop 80, a track 81 arranged along the test loop 80, and the loading device.

[0069] Compared with the prior art, the loop acceleration loading test system provided by the present application adopts the above-mentioned loading device, can feed back the influence data of the road performance on the sideslip of the loading vehicle 60 during the overpassing process through the detection value of the pressure sensor 30, and can simulate the scene of the loading vehicle 60 on the uphill and downhill by flexibly adjusting the pushing force of the loading cylinder 50 by the adjusting member 70, thereby further improving the comprehensiveness of data acquisition of the acceleration loading test.

[0070] The above only describes the preferred embodiments of the present application and should not be used to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A loading device, characterized in that The utility model relates to a kind of loadings of test loop, including: Gantry frame, two sides are respectively provided with rail wheel group, two sides The rail wheel group is respectively used to hold and roll pressure test loop both sides of track from top to bottom; Support frame, along the road surface width direction of the test loop Sliding connection is established in the middle of the gantry frame, and the support frame both sides With the gantry frame between It is equipped with pressure sensor; Uniform load beam, one side is hinged to the support frame, the other side is connected with the support frame by loading cylinder; Loading car, middle part is equipped with connecting beam, the connecting beam is hinged with the middle part of the uniform load beam; Wherein, the loading cylinder is used to push the uniform load beam to make the loading car to the road surface of the test loop Load, and the loading cylinder has for the flexible adjustment its push force degree Adjusting part, the pressure sensor is used to detect the lateral force when the loading car passes through bend It is transmitted to the support frame.

2. The loading device of claim 1, wherein, The loading cylinder includes: Cylinder body, hinged to the outside of the support frame and equipped with the adjusting part; Pressure regulating piston, sliding connection is established in the cylinder body and is driving connection with the adjusting part, the pressure regulating piston separates the inside of the cylinder body into sealed medium cavity, the medium cavity is filled with fluid; Loading piston, sliding connection is established in the medium cavity, the loading piston has loading rod that is sealed downward and is hinged with the uniform load beam out of the cylinder body, and the loading piston has up and down through Damping hole; Wherein, the adjusting part is used to drive the pressure regulating piston to move up and down to adjust the volume of the medium cavity, the damping hole is used to balance the fluid pressure on both sides of the loading piston.

3. The loading device of claim 2, wherein, The loading piston separates the medium cavity into rodless cavity and rod cavity up and down;The first high-pressure air bag is arranged in the rodless cavity, and the second high-pressure air bag is arranged in the rod cavity.

4. The loading device of claim 2, wherein, The loading piston has liquid flow hole that is penetrated up and down, and the liquid flow hole is provided with liquid flow valve;Wherein, the liquid flow valve opens when the fluid pressure difference on both sides of the loading piston is greater than the set threshold value, and closes when the fluid pressure difference on both sides of the loading piston is less than or equal to the set threshold value.

5. The loading device of claim 4, wherein, The liquid flow valve includes: Valve body, embedded in the liquid flow hole, the center of the valve body is provided with valve hole along its axial direction, the valve hole includes small diameter section and two large diameter sections respectively located at both ends of the small diameter section; Valve core, sliding connection is established in the small diameter section, the center of the valve core is provided with through hole, the middle part of the outer periphery of the valve core is provided with ring groove, and the ring groove is communicated with the through hole through radial hole; Two valve rods are respectively fixedly connected in two large diameter sections, and are respectively inserted with both ends of the through hole, and two valve rods are respectively provided with elastic element abutting against the valve core; Wherein, when the fluid pressure difference on both sides of the loading piston is greater than the set threshold value, the valve core overcomes the elastic force of the elastic element based on pressure difference and slides to the low pressure side to open state;When the fluid pressure difference on both sides of the loading piston is equal to or less than the set threshold value, the valve core resets and keeps closed state under the action of the elastic force of the elastic element.

6. The loading device of claim 2, wherein, The adjusting part includes: Rotary driving part, fixedly connected to the outer wall of the cylinder body; Turn sleeve, rotationally connected to the center of the top wall of the cylinder body; A driving rod is connected to the pressure regulating piston at one end and is in transmission connection with the output end of the rotary driving member at the other end, and the driving rod is in screw connection with the rotating sleeve.

7. The loading device of claim 1, wherein, The front and rear ends of the portal frame are oppositely provided with sliding grooves, and the front and rear ends of the bearing frame are correspondingly and slidingly connected into the two sliding grooves. Two pushers are oppositely arranged in each sliding groove, and the two pushers are respectively arranged on the two sides of the bearing frame, and the pressure sensor is arranged between each pusher and the bearing frame.

8. The loading device of claim 7, wherein, The pusher is a telescopic cylinder, the output end of the telescopic cylinder is provided with an elastic support, and the pressure sensor is arranged between the elastic support and the side wall of the bearing frame.

9. The loading device of claim 7, wherein, The end of the bearing frame extending into the sliding groove is provided with a roller on the upper and lower sides, and each roller is rolled on the groove wall of the sliding groove.

10. A ring road acceleration loading test system characterized by, The test track, the track arranged along the test track, and the loading device according to any one of claims 1-9 are included.

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