A testing system and method for bending fatigue and friction wear of elevator traction steel belts

Abstract

This invention discloses a testing system and method for bending fatigue and frictional wear of elevator traction steel belts. The system includes a drive unit, a traction sheave, a steel belt, a fatigue wheel, a wrap angle adjustment unit, a loading unit, a condition monitoring unit, and a frame. This testing system can perform simultaneous fatigue tests on multiple steel belts, effectively increasing the number of fatigue effect test sections and improving testing efficiency. By adjusting the position of the steel belt, the system can simulate the elevator frictional wear behavior under various working conditions such as different loads, wrap angles, speeds, and strokes, and monitor in real time the temperature changes between the steel belt coating and the traction sheave, as well as the creep behavior of the steel belt surface coating. The system reveals the frictional wear mechanism and fatigue damage evolution mechanism between the steel belt and the traction sheave.

Description

Technical Field

[0001] This invention relates to the technical field of a testing system for bending fatigue and friction wear of elevator traction steel belts, applicable to monitoring the frictional slippage behavior of elevator steel belts and traction sheaves and monitoring fatigue damage of multiple steel belts. Background Technology

[0002] Elevators rely on a traction system for power, with the traction steel belt being a crucial transmission component connecting the elevator car. Its load-bearing capacity directly impacts the elevator's operational safety and reliability. With the rapid development of elevator manufacturing technology, traction steel belts have become widely used. Compared to traditional steel wire ropes, traction steel belts offer advantages such as longer lifespan, lighter weight, easier maintenance, and better energy efficiency. In actual operation, traction elevators use the traction force generated by the friction between the steel belt and the traction sheave to propel the car up and down. When there are significant differences in the number of people entering and exiting the elevator and its stopping position, the car and counterweight will generate different traction forces in their respective directions, causing the elevator to become unbalanced. This increases the tension difference between the two ends of the steel belt, leading to slippage between the steel belt and the traction sheave, which endangers elevator safety. Although the designed service life of traction steel belts is much longer than that of steel wire ropes, typically around 20 years... However, in actual use, due to the influence of design factors, installation factors, maintenance factors, and environmental factors, and simultaneously experiencing frictional contact fatigue and bending fatigue, the surface coating of the traction steel belt is prone to cracking, aging, and damage such as broken or even fractured steel wire ropes in the load-bearing body, which seriously threatens its friction transmission performance. Therefore, a simulation test device and method for elevator steel belt slippage friction and bending fatigue is proposed to explore the dynamic friction slippage behavior and bending fatigue damage mechanism of elevator steel belt and traction sheave. This is of great significance for the structural design and maintenance of steel belt and traction sheave, reducing damage and extending their service life.

[0003] Patent No. 201310176077.X discloses an elevator traction drive friction testing device and method. A hydraulic cylinder drives the loading, and a motor drives the traction sheave to rotate continuously and slowly, creating a continuously increasing tension difference within the steel wire ropes on both sides of the traction sheave. The maximum static friction force is measured by measuring the maximum value of the tension difference. This allows for continuous static and sliding friction tests without motor stalling.

[0004] Patent No. 202123317364.7 discloses an elevator traction machine working condition simulation test device, which simulates the on-site working conditions of the traction machine and realizes the measurement and control feedback of the traction machine working condition.

[0005] Patent No. 202010708884.1 discloses a dynamic testing device for the friction coefficient between elevator steel belt and traction wheel, which makes the dynamic testing of the friction coefficient between elevator steel belt and traction wheel simpler and more convenient.

[0006] None of the aforementioned patents considered slippage wear between the elevator steel belt and the traction sheave, nor did they involve bending fatigue tests on multiple steel belts. Slippage between the steel belt and the traction sheave can easily lead to belt drive failure, and bending fatigue wear of the steel belt can easily cause it to break, seriously affecting elevator operational safety. Therefore, without understanding the wear mechanism of frictional slippage when the elevator slips against the traction sheave and the evolution mechanism of bending fatigue damage in the steel belt, it is difficult to solve the safety issues of elevator steel belts during service.

[0007] Based on the above analysis, it is necessary to develop a simulation test system for elevator steel belt slippage friction and bending fatigue in order to fully understand the wear characteristics and bending fatigue damage mechanism of steel belt under friction slippage and ensure the safe and reliable operation of the system equipment. Summary of the Invention

[0008] The purpose of this invention is to provide a testing system and method for bending fatigue and frictional wear of elevator traction steel belts. This system can realize the frictional slippage behavior of the steel belt-traction sheave under various working conditions such as different loads, wrap angles, speeds, and strokes, and can monitor the vibration, noise, and temperature between the steel belt and the traction sheave in real time. It reveals the changing laws of the frictional characteristics between the steel belt and the traction sheave, obtains the noise, vibration, and real-time temperature changes at the friction interface, and understands the frictional slippage relationship between the steel belt and the traction sheave. By adjusting the drive device, multiple steel belts can be simultaneously subjected to bending fatigue tests, allowing for the understanding of the bending fatigue damage evolution mechanism of the steel belt and the prediction of the lifespan of elevator steel belts.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] A testing system for bending fatigue and friction wear of elevator traction steel belts includes:

[0011] The frame has a traction sheave fixedly connected to its upper part via a traction sheave mounting bracket;

[0012] A loading unit is located at the lower part of the frame and is equipped with a steel pulley.

[0013] A friction drive unit is used to drive the traction sheave to rotate, thereby generating relative frictional slippage between the traction sheave and the steel belt.

[0014] The wrap angle adjustment unit is used to adjust the wrap angle between the steel belt and the traction sheave, including: two horizontal displacement adjustment mechanisms disposed on the frame and located below the traction sheave, namely a first horizontal displacement adjustment mechanism and a second horizontal displacement adjustment mechanism. The two horizontal displacement adjustment mechanisms are arranged symmetrically about the wheel axle of the traction sheave, and a guide wheel is fixed on each horizontal displacement adjustment mechanism by a mounting seat.

[0015] A bending fatigue drive assembly for performing bending fatigue testing on the steel strip includes: two horizontal displacement adjustment mechanisms mounted on the frame and located on the left and right sides of the traction sheave, namely a third horizontal displacement adjustment mechanism and a fourth horizontal displacement adjustment mechanism.

[0016] And a vertical displacement adjustment mechanism located directly below the traction sheave;

[0017] A fatigue wheel is fixed to the third horizontal displacement adjustment mechanism via a mounting base.

[0018] The fatigue wheel 2 is fixed to the fourth horizontal displacement adjustment mechanism by a mounting seat;

[0019] The vertical displacement adjustment mechanism is fixed with fatigue wheel three via a mounting base;

[0020] A fatigue drive assembly, mounted on the frame and located on one side of the steel strip, is used to control the steel strip to perform lateral reciprocating motion to simulate the bending fatigue of the steel strip.

[0021] Vibration sensors are used to monitor the vibration frequency of the steel strip during frictional slippage in real time;

[0022] A noise sensor is used to monitor the noise during frictional slippage of the steel strip in real time;

[0023] A tension sensor is used to monitor the tension change of the steel belt in real time and indirectly calculate the friction coefficient between the steel belt and the traction sheave.

[0024] A high-speed industrial camera, combined with markings on the surface of the steel strip, was used to observe the creep deformation of the steel strip during a friction test.

[0025] Infrared thermal imagers are used to monitor the temperature changes at the friction interface between the steel belt and the traction sheave in real time.

[0026] The loading unit includes:

[0027] The support frame is vertically slidingly supported by support pulleys.

[0028] The counterweight is placed on the support frame;

[0029] The steel pulley is fixedly connected to the support frame via a fixed shaft.

[0030] The friction drive unit includes:

[0031] The first motor is mounted on the frame via a motor mounting bracket, and the drive shaft of the first motor is connected to the traction wheel via a first reducer.

[0032] Both the horizontal displacement adjustment mechanism and the vertical displacement adjustment mechanism are hand-cranked screw mechanisms.

[0033] The fatigue drive component includes:

[0034] The second motor is mounted on the frame via a motor mounting bracket, and the drive shaft of the second motor is connected to a crankshaft via a second reducer.

[0035] The other end of the crankshaft is hinged to one end of a power rod one, and the other end of the power rod one is fixedly connected to the rod wall of a power rod two through a flange bearing seat. One end of the power rod two is connected to the frame through a rotating seat, and the other end is connected to the steel belt.

[0036] The rotation of the second motor can drive one end of the second power rod to rotate around the rotating seat, thereby driving the steel belt to reciprocate.

[0037] The frame is provided with support rollers on the other side of the steel belt to prevent the steel belt from shifting during reciprocating motion.

[0038] The vibration sensor is a patch-type vibration sensor fixed on the steel strip;

[0039] The noise sensor is a patch-type noise sensor fixed on the traction sheave;

[0040] The high-speed industrial camera and infrared thermal imager are fixed on a fixed support plate, with the lens facing the contact surface between the steel belt and the traction wheel.

[0041] The present invention further discloses a test method for friction and wear testing using the elevator traction steel belt bending fatigue and friction and wear testing system, comprising the following steps:

[0042] a. The guide wheel is moved horizontally by the first and second horizontal displacement adjustment mechanisms. The position of the guide wheel is adjusted so that the wrap angle of the steel belt on the traction wheel meets the test requirements. The test steel belt is passed over the traction wheel and around the guide wheel, and fixed by the steel belt clamp.

[0043] b. The lower steel belt is fixed by a steel belt clamp, and the lower steel belt passes around the steel belt pulley to form a closed loop;

[0044] c. Apply load using the loading unit to bring the reading of the tension sensor to the initial tension value;

[0045] d. Control the friction drive unit to drive the traction wheel to rotate, causing frictional slippage between the steel strip coating and the traction wheel. Record the tension changes of the steel strip on both sides of the traction wheel using a tension sensor, and test the friction coefficient value using Euler's formula. Record the vibration frequency of the steel strip during the test using the vibration sensor. Test the noise value of the steel strip during the friction test using the noise sensor.

[0046] e. Real-time synchronous monitoring of temperature changes at the friction interface between the steel strip and the traction wheel is achieved using an infrared thermal imager; the creep deformation of the steel strip during the friction test is observed by marking the surface of the steel strip and combining it with the rapid imaging capability of a high-speed industrial camera.

[0047] f. When the number of rotations of the traction sheave reaches the set value, shut down the friction drive unit and unload the loading unit; remove the upper steel belt from the steel belt clamp;

[0048] g. By changing the frequency and forward / reverse amplitude of the friction drive unit, the loading force of the loading unit, the angle of wrap, and replacing the traction wheel and steel belt with different materials, the friction slip behavior of the steel belt and traction wheel under different frequencies, loads, wrap angles, and friction pairs is studied. Wear surface features are detected by SEM-EDS and a three-dimensional topography measuring instrument, and the wear mechanism of the traction steel belt is analyzed and revealed.

[0049] Furthermore, the present invention also discloses a test method for conducting bending fatigue testing of traction steel belts using the aforementioned elevator traction steel belt bending fatigue and friction wear testing system, comprising the following steps:

[0050] 1. The guide wheel moves horizontally through the first and second horizontal displacement adjustment mechanisms. The horizontal positions of fatigue wheel one and fatigue wheel two are controlled through the third and fourth horizontal displacement adjustment mechanisms. The vertical movement of fatigue wheel three is controlled through the vertical displacement adjustment mechanism to determine the vertical position of fatigue wheel three, so that the bending angle of the steel strip on the fatigue wheel meets the test requirements.

[0051] 2. The steel strips first pass over fatigue wheel one from above, then pass under fatigue wheel three, and finally pass over fatigue wheel two from above. The tension values ​​of multiple steel strips are monitored in real time by the first tension sensor.

[0052] 3. Apply load using the loading unit to bring the reading of the first tension sensor to the initial tension value;

[0053] 4. The reciprocating motion of the steel belt is controlled by a fatigue-driven component;

[0054] 5. Record the number of reciprocating strokes of the steel strip using a counter;

[0055] 6. When the number of reciprocating motions of the steel belt reaches the set time, the fatigue drive component is turned off and the loading unit unloads the load; the steel belt is then removed from the steel belt clamp.

[0056] Beneficial effects:

[0057] First, this invention uses a hand-cranked screw to control the position of the guide wheel and adjust the wrap angle to conduct friction tests on the steel belt-traction wheel under different wrap angle conditions; a support pulley is added to fix the position of the friction steel belt, avoiding the influence of steel belt displacement on the test results. It can actively adjust experimental parameters such as contact load, wrap angle, sliding speed, and stroke during the test, revealing the influence of different working conditions on the tribological characteristic parameters of the steel belt-traction wheel.

[0058] Second, compared with the prior art, the present invention changes the driving device to change the test bench from a friction test bench to a fatigue test bench and realizes the synchronous bending fatigue test of multiple steel strips.

[0059] Third, this invention observes the vibration and noise changes of the steel belt and traction wheel in real time by installing patch vibration sensors and patch noise sensors on the steel belt and traction wheel, uses an infrared thermal imager to monitor the temperature changes between the contact interface of the steel belt and traction wheel in real time, and observes the creep deformation of the steel belt during the friction test by marking the surface of the steel belt and combining the rapid imaging capability of a high-speed industrial camera. Attached Figure Description

[0060] Figure 1 This is a schematic diagram of the elevator traction steel belt bending fatigue and friction wear testing system of the present invention;

[0061] Figure 2 This is a front view of the elevator traction steel belt bending fatigue and friction wear testing system of the present invention;

[0062] Figure 3 This is a partially enlarged view of the fatigue drive device of the present invention;

[0063] Figure 4 This is a partially enlarged view of the wrap angle adjustment unit of the present invention;

[0064] Figure 5 This is a partially enlarged view of the fatigue fixation of multiple steel strips in this invention;

[0065] Figure 6 This is a schematic diagram of the friction test structure of the present invention;

[0066] Figure 7 A magnified view of the marked points on the contact surface between the steel belt and the traction sheave;

[0067] Figure label:

[0068] 1-1 Fatigue wheel one; 1-2 Fatigue wheel two; 1-3 Fatigue wheel three; 2. Traction wheel; 3-1 Fixed support plate one; 3-2 Fixed support plate two; 3-2 Fixed support plate three; 4. Carbon steel bracket; 5-1 Hand-cranked screw one; 5-2 Hand-cranked screw two; 5-3 Hand-cranked screw three; 6-1 Hand-cranked screw four; 6-2 Hand-cranked screw five; 7. Steel belt; 8. Support plate; 9. Support pulley; 10. Counterweight; 11-1 Roller; 11-2 Roller 12. Base; 13. Bearing frame; 14. Steel pulley; 15. Second motor mounting plate; 16. First motor mounting plate; 17-1. Fatigue steel belt clamp one; 17-2. Spherical plain bearing one; 17-3. Spherical plain bearing two; 17-4. First tension sensor; 17-5. Fixed seat one; 17-6. Fixed seat two; 17-7. Spherical plain bearing three; 17-8. Fatigue steel belt clamp three; 18-1. Bearing with seat five; 18-2. Bearing with seat six; 19. Rotating shaft; 20-1, Second motor; 20-2, Worm gear reducer; 20-3, Mounted bearing three; 20-4, Mounted bearing four; 21, Drive shaft; 22-1, Crank; 22-2, Power lever one; 22-3, Power lever two; 23, Flange bearing housing; 24-1, Equalizing seat one; 24-2, Equalizing seat two; 25-1, Mounted bearing one; 25-2, Mounted bearing two; 26, Connecting shaft; 27-1, Diaphragm coupling; 27-2, Reducer; 2 7-3, First motor; 28-1, Guide wheel one; 28-2, Guide wheel two; 29, Upper steel belt; 30-1, Steel belt clamp one; 30-2, Steel belt clamp two; 30-3, Steel belt clamp three; 30-4, Steel belt clamp four; 31-1, Second tension sensor; 31-2, Third tension sensor; 32, Lower steel belt; 33, Vibration sensor; 34, Noise sensor; 35, High-speed industrial camera; 36, Infrared thermal imager; 37, Steel belt surface marking; 38, Counter. Detailed Implementation

[0069] The technical solution of the present invention will be further explained below with reference to the accompanying drawings and specific embodiments.

[0070] like Figure 1-6 As shown, an elevator traction steel belt bending fatigue and friction wear testing system and method includes a drive unit, traction sheave, steel belt, fatigue wheel, wrap angle adjustment unit, loading unit, condition monitoring unit and frame, etc.

[0071] The drive unit is fixed on the frame, the traction wheel and fatigue wheel are respectively connected to the support plate fixed on the frame, the loading unit is connected to the steel belt, and the condition monitoring unit is fixed around the steel belt and traction wheel to perform real-time dynamic monitoring of the friction characteristics of the steel belt-traction wheel.

[0072] The frame includes a base 12, a carbon steel bracket 4 welded to the base, a support plate 8, a second motor mounting plate 15 fixed to the bracket, and a first motor mounting plate 16.

[0073] The driving devices are a friction driving unit and a fatigue driving unit. The friction driving unit includes a traction sheave 2, a first bearing 25-1, a second bearing 25-2, a connecting shaft 26, a diaphragm coupling 27-1, a reducer 27-2, and a first motor 27-3. The output shaft of the first motor 27-3 is connected to the input shaft of the reducer 27-2. The output shaft of the reducer is connected to the connecting shaft 26 via the diaphragm coupling 27-1. The connecting shaft 26 is connected to the traction sheave 2 and is fixed on the frame via the first bearing 25-1 and the second bearing 25-1.

[0074] The fatigue drive unit is fixed on the second motor mounting plate 15 and includes a second motor 20-1, a worm gear reducer 20-2, a seated bearing 3 20-3, a seated bearing 4 20-4, a drive shaft 21, a crank 22-1, a power lever 1 22-2, a power lever 22-3, a flange bearing seat 23, a seated bearing 5 18-1, a seated bearing 6 18-2, and a rotating shaft 19. The output shaft of the second motor 20-1 is connected to the input shaft of the worm gear reducer 20-2. The worm gear reducer 20-2 is connected to the drive shaft 21 and is fixed to the second motor mounting plate 16 through the bearing three 25-1 and bearing four 25-1. The drive shaft 21 is connected to the crank 22-1 and the crank 22-1 is connected to the power lever one 22-2. The power lever one 22-2 and the power lever two 22-3 are fixedly connected through the flange bearing seat 23. The rotating shaft 19 is connected to the bearing five 18-1 and bearing six 18-2. The power lever two 22-3 is installed on the rotating shaft 19 to realize the reciprocating motion of the steel belt.

[0075] The steel strip clamping device is divided into a friction steel strip clamping device and a fatigue steel strip clamping device. The friction steel strip clamping device includes an upper steel strip 29, a steel strip clamp 1 30-1, a steel strip clamp 2 30-2, a steel strip clamp 30-3, a steel strip clamp 4 30-4, a tension sensor 1 31-1, a tension sensor 2 31-2, and a lower steel strip 32. The two ends of the upper steel strip 29 are fixed by the steel strip clamp 1 30-1 and the steel strip clamp 2 30-2. The steel strip clamp 1 30-1 and the steel strip clamp 2 30-2 are connected to the sensor 1 31-1 and the tension sensor 2 31-2 respectively through spherical bearings. The tension sensor 1 31-1 and the tension sensor 2 31-2 are connected to the steel strip clamp 30-3 and the steel strip clamp 4 30-4 respectively. The two ends of the lower steel strip 32 are fixed by the steel strip clamp 30-3 and the steel strip clamp 4 30-4, so as to realize the tension measurement of both sides of the steel strip during the friction experiment. The fatigue steel strip clamping device includes a steel strip 7, a fatigue steel strip clamp 17-1, a spherical bearing 17-2, a spherical bearing 27-3, a first tension sensor 17-4, a fixed seat 17-5, a fixed seat 2 17-6, a spherical bearing 3 17-7, and a fatigue steel strip clamp 3 17-8. The two ends of the steel strip 7 are connected to the steel strip clamp 17-1 and the fatigue steel strip clamp 2 17-8 respectively. The fatigue steel strip clamp 17-1 is connected to the upper end of the spherical bearing 17-2, and the lower end of the spherical bearing 17-2 is connected to the tension sensor 17-4. The first tension sensor 17-4 is connected to the fixed seat 17-5 through the spherical bearing 2 17-3. The fixed seats 17-5 and 2 17-6 are connected to the power lever 22-3. The fixed seat 2 17-6 is connected to the fatigue steel strip clamp 3 17-8 through the spherical bearing 3 17-7, realizing real-time monitoring of the tension during the fatigue test of the steel strip.

[0076] The loading unit is mounted on the frame and connected to the steel belt 7. It includes a counterweight 10, a support pulley 10, a roller 11-1, a roller seat 11-2, a support frame 13, and a steel belt pulley 14. The support pulley 10 is fixed to the support frame 13 via the roller seat 11-2. The support pulley 10 restricts the loading unit's freedom in the horizontal direction, providing only vertical movement for the loading unit. The steel belt 7 is connected to the steel belt pulley 14. Applying the counterweight 10 achieves different forces during friction and fatigue tests.

[0077] The fatigue wheel includes fatigue wheel 1-1 and fatigue wheel 1-2 mounted on fixed support plate 1-1 and fixed support plate 2-2, respectively, and fatigue wheel 3 mounted on fixed support plate 3-2. The steel belt 7 passes through the top of fatigue wheel 1-1, the bottom of fatigue wheel 1-2, and the top of fatigue wheel 3-3, respectively, to simulate the bending fatigue state of the steel belt. The hand crank screw 1-5-1 and the hand crank screw 2-2 are fixed on fixed support plate 1-1 and fixed support plate 2-2, respectively, to control the horizontal movement of the fatigue wheel. The hand crank screw 3-5-3 controls the vertical movement of fatigue wheel 3-3, thereby adjusting the different fatigue angles of the steel belt 7.

[0078] The wrap angle adjustment unit includes a hand-cranked lead screw 4 6-1, a hand-cranked lead screw 5 6-2, a guide wheel 1 28-1, a guide wheel 28-2, a leveling seat 1 24-1, and a leveling seat 2 24-2. The guide wheel 1 28-1 and guide wheel 28-2 are respectively fixed to leveling seats 1 24-1 and 2 24-2. The hand-cranked lead screw 4 6-1 and hand-cranked lead screw 5 6-2 are respectively fixed to the sides of leveling seats 1 24-1 and 2 24-2, controlling the horizontal movement of the guide wheels. The horizontal movement of the guide wheels adjusts the wrap angle of the steel belt on the traction sheave.

[0079] The status monitoring unit includes a vibration sensor 33, a noise sensor 34, a high-speed industrial camera 35, an infrared thermal imager 36, and a friction tension sensor. The patch-type vibration sensor 33 is fixed to the upper steel strip 29 to monitor the vibration frequency of the steel strip during frictional slippage in real time. The patch-type noise sensor 34 is fixed to the traction sheave 2 to monitor the noise of the steel strip during frictional slippage in real time. The high-speed industrial camera and infrared thermal imager are fixed to a fixed support plate 3-1, with the lens facing the contact surface between the steel strip and the traction sheave. Through the markings 37 on the steel strip surface, combined with the rapid imaging capability of the high-speed industrial camera 35, the creep deformation of the steel strip during the friction test is observed. The infrared thermal imager 36 synchronously monitors the temperature change between the contact interface between the steel strip and the traction sheave in real time. The second tension sensor 31-1 and the third tension sensor 31-2 are used to monitor the tension changes on both sides of the steel strip during movement, indirectly calculating the friction coefficient between the steel strip and the traction sheave.

[0080] Using the above-mentioned test method for bending fatigue and friction wear of elevator traction steel belts, the specific steps of the friction test are as follows:

[0081] The forward and backward movement of the leveling seat 24 is controlled by hand-cranked screws four and five, thereby moving the guide wheel 28 horizontally. The position of the guide wheel 28 is adjusted so that the wrap angle of the steel belt 29 on the traction sheave meets the test requirements. The test steel belt passes over the traction sheave 2 and around the guide wheel 28, and is fixed by the steel belt clamp 30. The steel belt clamp 30 fixes the lower steel belt 32, which wraps around the steel belt pulley 14 to form a closed loop, and the support pulley 9 prevents the steel belt from shifting. A counterweight 10 is applied to the bearing frame 13 so that the reading of the tension sensor reaches the initial tension value. The first motor 27-3 is controlled to drive the traction sheave 2 to rotate, causing frictional slippage between the covering layer and the traction sheave. The tension sensor records the tension change of the steel belt on both sides of the traction sheave 2, and the friction coefficient value is tested using Euler's formula. The vibration frequency of the steel belt during the test is recorded by the vibration sensor 33. The noise value of the steel belt during the friction test is tested by the noise sensor 34. The temperature change at the friction interface between the steel belt and the traction sheave is monitored in real time using an infrared thermal imager 36. The creep deformation of the steel belt during the friction test is observed through markings on the steel belt surface combined with the rapid imaging capability of a high-speed industrial camera. When the number of rotations of the traction sheave 2 reaches the set value, the first motor 27-3 is turned off, and the counterweight 9 is unloaded; the upper steel belt 29 is removed from the steel belt clamp 30. By changing the frequency and forward / reverse amplitude of the first motor 27-3, the size of the counterweight 10, the wrap angle, and by replacing the traction sheave and steel belt with different materials, the frictional slippage behavior of the steel belt and traction sheave under different frequencies, loads, wrap angles, and friction pairs is studied. Wear surface characteristics are detected using SEM-EDS and a three-dimensional topography measuring instrument, enabling analysis and revelation of the wear mechanism of the traction steel belt. Using the above-mentioned elevator traction steel belt bending fatigue and friction wear test method, the specific steps for bending fatigue are as follows:

[0082] The guide wheel moves horizontally by controlling the forward and backward movement of fatigue wheels 1-1 and 1-2 via hand-cranked screws 1-1 and 5-2, respectively. The fatigue wheel 1-3 moves vertically by controlling its up and down movement via hand-cranked screw 5-3. The position of fatigue wheel 1 is adjusted so that the bending angle of the steel strip 7 on the fatigue wheel meets the test requirements. The four steel strips pass sequentially around fatigue wheel 1-1 from above, then around fatigue wheel 1-3 from below, and finally around fatigue wheel 1-2 from above. The four steel strips are fixed sequentially to steel strip clamp 17-1, and the tension value of multiple steel strips is monitored in real time by the first tension sensor 17-2. A counterweight 10 is applied to the support frame 13 to make the reading of the first tension sensor 17-3 reach the initial tension value; the second motor 20-1 is connected to the crank-connecting rod mechanism 22, the motor is started, the crank begins to rotate, and the connecting rod converts the rotational motion into linear motion, controlling the reciprocating motion of the steel belt through the second power lever 22-3; the support pulley 9 prevents the steel belt from deviating. The counter 38 records the number of reciprocating motions of the steel belt; when the number of reciprocating motions of the steel belt reaches the set number, the second motor 20-1 is turned off, the counterweight 10 is unloaded, and the steel belt 7 is removed from the steel belt clamp 17-1. It should be understood that, for those skilled in the art, although this specification describes embodiments, not every embodiment contains only one independent technical solution. This descriptive method is only for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each example can be appropriately combined to form other embodiments that can be understood by those skilled in the art. All such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A testing system for bending fatigue and friction wear of elevator traction steel belts, characterized in that, include: The frame has a traction sheave fixedly connected to its upper part via a traction sheave mounting bracket; A loading unit is located at the lower part of the frame and is equipped with a steel pulley. A friction drive unit is used to drive the traction sheave to rotate, thereby generating relative frictional slippage between the traction sheave and the steel belt. The wrap angle adjustment unit is used to adjust the wrap angle between the steel belt and the traction sheave, including: two horizontal displacement adjustment mechanisms disposed on the frame and located below the traction sheave, namely a first horizontal displacement adjustment mechanism and a second horizontal displacement adjustment mechanism. The two horizontal displacement adjustment mechanisms are arranged symmetrically about the wheel axle of the traction sheave, and a guide wheel is fixed on each horizontal displacement adjustment mechanism by a mounting seat. A bending fatigue drive assembly for performing bending fatigue testing on the steel strip includes: two horizontal displacement adjustment mechanisms mounted on the frame and located on the left and right sides of the traction sheave, namely a third horizontal displacement adjustment mechanism and a fourth horizontal displacement adjustment mechanism. And a vertical displacement adjustment mechanism located directly below the traction sheave; A fatigue wheel is fixed to the third horizontal displacement adjustment mechanism via a mounting base. The fatigue wheel 2 is fixed to the fourth horizontal displacement adjustment mechanism by a mounting seat; The vertical displacement adjustment mechanism is fixed with fatigue wheel three via a mounting base; A fatigue drive assembly, mounted on the frame and located on one side of the steel strip, is used to control the steel strip to perform lateral reciprocating motion to simulate the bending fatigue of the steel strip. Vibration sensors are used to monitor the vibration frequency of the steel strip during frictional slippage in real time; A noise sensor is used to monitor the noise during frictional slippage of the steel strip in real time; A tension sensor is used to monitor the tension change of the steel belt in real time and indirectly calculate the friction coefficient between the steel belt and the traction sheave. A high-speed industrial camera, combined with markings on the surface of the steel strip, was used to observe the creep deformation of the steel strip during a friction test. Infrared thermal imager is used to monitor the temperature changes at the friction interface between the steel belt and the traction sheave in real time. The fatigue drive assembly includes: a second motor, which is mounted on the frame via a motor mounting bracket, and the drive shaft of the second motor is connected to a crankshaft via a second reducer; The other end of the crankshaft is hinged to one end of a power rod one, and the other end of the power rod one is fixedly connected to the rod wall of a power rod two through a flange bearing seat. One end of the power rod two is connected to the frame through a rotating seat, and the other end is connected to the steel belt. The rotation of the second motor can drive one end of the second power rod to rotate around the rotating seat, thereby driving the steel belt to reciprocate. The frame is provided with support rollers on the other side of the steel belt to prevent the steel belt from shifting during reciprocating motion.

2. The elevator traction steel belt bending fatigue and friction wear testing system according to claim 1, characterized in that, The loading unit includes a support frame, which is vertically slidingly supported by a support pulley; The counterweight is placed on the support frame; The steel pulley is fixedly connected to the support frame via a fixed shaft.

3. The elevator traction steel belt bending fatigue and friction wear testing system according to claim 1, characterized in that, The friction drive unit includes: a first motor, which is mounted on the frame via a motor mounting bracket, and the drive shaft of the first motor is connected to the traction wheel via a first reducer.

4. The elevator traction steel belt bending fatigue and friction wear testing system according to claim 1, characterized in that, Both the horizontal displacement adjustment mechanism and the vertical displacement adjustment mechanism are hand-cranked screw mechanisms.

5. The elevator traction steel belt bending fatigue and friction wear testing system according to claim 1, characterized in that, The vibration sensor is a patch-type vibration sensor fixed on the steel strip; The noise sensor is a patch-type noise sensor fixed on the traction sheave; The high-speed industrial camera and infrared thermal imager are fixed on a fixed support plate, with the lens facing the contact surface between the steel belt and the traction wheel.

6. A test method for conducting friction and wear tests using the elevator traction steel belt bending fatigue and friction and wear testing system described in any one of claims 1 to 5, characterized in that, Includes the following steps: a. The guide wheel is moved horizontally by the first and second horizontal displacement adjustment mechanisms. The position of the guide wheel is adjusted so that the wrap angle of the steel belt on the traction wheel meets the test requirements. The test steel belt is passed over the traction wheel and around the guide wheel, and fixed by the steel belt clamp. b. The lower steel belt is fixed by a steel belt clamp, and the lower steel belt passes around the steel belt pulley to form a closed loop; c. Apply load using the loading unit to bring the reading of the tension sensor to the initial tension value; d. Control the friction drive unit to drive the traction wheel to rotate, causing frictional slippage between the steel strip coating and the traction wheel. Record the tension changes of the steel strip on both sides of the traction wheel using a tension sensor, and test the friction coefficient value using Euler's formula. Record the vibration frequency of the steel strip during the test using the vibration sensor. Test the noise value of the steel strip during the friction test using the noise sensor. e. Real-time synchronous monitoring of temperature changes at the friction interface between the steel strip and the traction wheel is achieved using an infrared thermal imager; the creep deformation of the steel strip during the friction test is observed by marking the surface of the steel strip and combining it with the rapid imaging capability of a high-speed industrial camera. f. When the number of rotations of the traction sheave reaches the set value, shut down the friction drive unit and unload the loading unit; remove the upper steel belt from the steel belt clamp; g. By changing the frequency and forward / reverse amplitude of the friction drive unit, the loading force of the loading unit, the angle of wrap, and replacing the traction wheel and steel belt with different materials, the friction slip behavior of the steel belt and traction wheel under different frequencies, loads, wrap angles, and friction pairs is studied. Wear surface features are detected by SEM-EDS and a three-dimensional topography measuring instrument, and the wear mechanism of the traction steel belt is analyzed and revealed.

7. A test method for conducting bending fatigue testing of elevator traction steel belts using the bending fatigue and friction wear testing system described in any one of claims 1 to 5, characterized in that, Includes the following steps: S1. The guide wheel moves horizontally through the first and second horizontal displacement adjustment mechanisms. The horizontal positions of fatigue wheel one and fatigue wheel two are controlled through the third and fourth horizontal displacement adjustment mechanisms. The vertical movement of fatigue wheel three is controlled through the vertical displacement adjustment mechanism to determine the vertical position of fatigue wheel three, so that the bending angle of the steel strip on the fatigue wheel meets the test requirements. S2. The steel strip first passes over fatigue wheel one from above, then passes under fatigue wheel three, and finally passes over fatigue wheel two from above. The tension value of multiple steel strips is monitored in real time by the first tension sensor. S3. Loading is performed using the loading unit to bring the reading of the first tension sensor to the initial tension value; S4. The steel belt is controlled to reciprocate using a fatigue-driven component; S5. Record the number of reciprocating strokes of the steel strip using a counter; S6. When the number of reciprocating motions of the steel belt reaches the set time, the fatigue drive component is turned off and the loading unit unloads the load; the steel belt is then removed from the steel belt clamp.

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