A fatigue testing apparatus and method for nylon guide wheels in elevators.

Abstract

This invention relates to a fatigue testing apparatus and method for nylon guide wheels used in elevators, comprising: a test platform; a pressurizing mechanism disposed on the test platform for applying alternating or static loads to the nylon guide wheel; a temperature control chamber connected to the test platform in a relatively movable manner, and having an internal test space for accommodating the nylon guide wheel; and a transmission mechanism connected in cooperation with the temperature control chamber, driving the temperature control chamber to move relative to the test platform to open or close, allowing the nylon guide wheel to be placed or removed within the test space. This invention simulates the actual working temperature conditions of the nylon wheel using the temperature control chamber, and applies alternating or static loads to the nylon wheel using the pressurizing mechanism, conducting fatigue tests under different temperatures and alternating loads to simulate relatively realistic working conditions. Furthermore, this apparatus is applicable to testing nylon wheels of different specifications.

Description

Technical Field

[0001] This invention relates to the field of elevator guide wheel testing technology, specifically to a fatigue testing device and method for elevator nylon guide wheels. Background Technology

[0002] Compared to cast iron guide wheels, nylon guide wheels used in elevators are widely used due to their advantages such as lighter weight, easier installation, lower price, noise absorption, and vibration reduction. For example, they are commonly used in elevator car anti-cord sheaves and counterweight anti-cord sheaves, and have become one of the mainstream configurations in traction drive elevator suspension systems. Nylon guide wheels play a crucial role in the safe operation of elevators; their failure directly affects elevator performance, and if not addressed promptly, can even compromise the safety of the entire elevator system. Therefore, it is necessary to conduct research on the lifespan and fatigue testing of elevator nylon guide wheels. Fatigue tests on elevator nylon guide wheels can be used to explore the failure mechanisms, influencing factors, and variation patterns, particularly by testing the condition and lifespan of bearings within the nylon wheel assembly. This provides strong technical support for preventing and addressing fatigue failure of elevator nylon guide wheels. In existing testing technologies, there is a testing fixture for nylon wheel bearings that uses a specially designed rotating component to directly contact the nylon wheel and generate compressive force, causing the rotating component to rotate synchronously with the nylon wheel until fatigue failure occurs, thus determining the quality of the nylon wheel. However, this technology has some problems: First, it only uses simulation to test the lifespan of elevator nylon guide wheels, without considering the influence of the nylon wheel groove on the test. In actual working conditions, the stress relationship between the groove and the wire rope has a certain impact on the operation of the nylon guide wheel. Second, it does not consider the impact of temperature and alternating loads on the fatigue life of the nylon guide wheel, and cannot simulate the actual working conditions and operational complexity of the nylon guide wheel. Therefore, how to develop a fatigue testing device for elevator nylon guide wheels that can simulate relatively realistic working conditions and conduct fatigue tests under different temperatures and alternating loads is an urgent problem to be solved. Summary of the Invention

[0003] To address the technical problems existing in the prior art, the first objective of this invention is to provide a fatigue testing device for elevator nylon guide wheels, comprising a testing platform, a pressurizing mechanism, a temperature control chamber, and a transmission mechanism, which can conduct tests under different temperatures and alternating loads to simulate relatively realistic working conditions in order to test fatigue characteristics (significant deformation, wear, cracks, fracture) and fatigue life and other parameters.

[0004] The second objective of this invention is to provide a fatigue testing method for elevator nylon guide wheels. This method simulates the actual working temperature conditions of the nylon wheel using a temperature control chamber, applies alternating or static loads to the nylon wheel using a pressurizing mechanism, and conducts fatigue tests under different temperatures and alternating loads to simulate relatively realistic working conditions. Furthermore, this device is applicable to testing nylon wheels of different specifications.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A fatigue testing device for elevator nylon guide wheels includes: a test platform; a pressurizing mechanism disposed on the test platform for applying alternating or static loads to the nylon guide wheels; a temperature control box connected to the test platform in a relatively movable manner, and having a test space inside to accommodate the nylon guide wheels; and a transmission mechanism connected in cooperation with the temperature control box to drive the temperature control box to move relative to the test platform, thereby opening or closing it, so that the nylon guide wheels can be placed or removed from the test space.

[0007] Furthermore, the pressurizing mechanism includes: a support frame, which is disposed on the test platform and located outside the temperature control chamber; a support, which is located within the test space and is used to support and fix the nylon guide wheel; and a pressurizing assembly, which includes a connecting rod, a universal pressure head, and a pressure plate arranged in series. One end of the connecting rod is disposed on the support frame and connected to a driver, and the other end extends downward and enters the test space from the top of the temperature control chamber. The bottom of the pressure plate is pressed against the circumferential wall of the nylon guide wheel at a certain wrap angle.

[0008] Furthermore, the connecting rod is also equipped with a pressure sensor to monitor and provide feedback on the pressure applied to the nylon guide wheel.

[0009] Furthermore, the support frame includes two columns disposed on the test platform and a crossbeam slidably disposed between the two columns for fixing the connecting rod. The distance between the pressure plate and the nylon guide wheel can be adjusted by adjusting the height of the crossbeam.

[0010] Furthermore, the universal pressure head includes an ear seat and a connecting shaft. The bottom of the ear seat abuts against the pressure plate, and a pin is disposed on the ear seat. The lower part of the connecting shaft is movably connected to the ear seat through the pin, and the upper part of the connecting shaft is detachably connected to the other end of the connecting rod.

[0011] Furthermore, the nylon guide wheel includes an outer wheel body, an inner wheel body, and multiple reinforcing ribs. One end of each of the multiple reinforcing ribs is fixed to the inner wheel body, while the other end extends and is fixed towards the outer wheel body at a certain angle. A process perforated plate is provided between two adjacent reinforcing ribs. Multiple first wheel grooves for winding steel wire rope are provided on the circumferential wall of the outer wheel body. A bearing is disposed on the inner wheel body, and a shaft is disposed on the bearing. Both ends of the shaft are supported on the support.

[0012] Furthermore, the bottom of the pressure plate has a second wheel groove that mates with the first wheel groove.

[0013] Furthermore, the temperature control chamber includes a cover and a chamber body. The cover is disposed on the test platform. One side of the chamber body is open and slidably connected to the cover. The other side of the chamber body is equipped with a heater for adjusting the temperature of the test space. The bottom of the other side of the chamber body is equipped with a support base for supporting the chamber body. The support base raises the other side of the chamber body a certain distance off the ground. The bottom of the support base is equipped with casters for moving the chamber body. A controller is also disposed on the outside of the chamber body.

[0014] Furthermore, the transmission mechanism includes a slide rail disposed at the bottom of the cover plate and a slide groove disposed at the bottom of the housing. The slide rail moves in the slide groove to control the opening or closing of the cover plate and the housing.

[0015] According to the method using the above-mentioned fatigue testing device for elevator nylon guide wheels, the method includes the following steps:

[0016] The nylon guide wheel to be tested is fixed on the support. The height of the crossbeam in the support frame is adjusted so that the pressure plate of the pressurizing component presses against the circumferential wall of the nylon guide wheel at a certain wrap angle. The temperature control box is moved relative to the test platform through the transmission mechanism, thereby closing the test space. The temperature in the test space is adjusted to the preset test temperature by the heater of the temperature control box. The pressurizing component is controlled by the driver to apply alternating load or static load to the nylon guide wheel. The pressure value applied to the nylon guide wheel is monitored and recorded by the pressure sensor. The nylon guide wheel is made to work continuously under the preset test conditions to simulate the fatigue process in actual working conditions.

[0017] The present invention has the following advantages:

[0018] 1. The fatigue testing device for elevator nylon guide wheels of the present invention controls the temperature conditions within the test space through a temperature control chamber, and combines this with the alternating load output to the nylon guide wheel by a pressurizing mechanism, thereby simulating various temperature and load changes encountered by the nylon guide wheel in actual operation. This highly simulated test environment makes the test results closer to real working conditions, thus more accurately evaluating the impact of different temperatures and alternating loads on the operating performance of the nylon wheel and its bearings.

[0019] 2. The pressurizing mechanism of this invention includes a support frame, a support base, and a pressurizing assembly. The pressurizing assembly includes a connecting rod, a universal pressure head, and a pressure plate arranged in series. It utilizes steel wire ropes with a specific wrap angle wrapped around the elevator nylon guide wheel as the force transmission medium. These steel wire ropes not only ensure the balanced force distribution on each rope of the nylon guide wheel but also achieve precise positioning and pressure transmission of the steel wire ropes through the second groove on the pressure plate. This effectively promotes a tight fit between the steel wire ropes and the nylon guide wheel, strictly adhering to the stringent requirements of industry standards for the uniformity of force distribution on the steel wire ropes. This design completely eliminates the slippage or displacement problem between the steel wire rope and the nylon guide wheel commonly found in traditional rope-pulling tests, improving the accuracy and reliability of the test and avoiding potential deviations in test results caused by slippage of the nylon guide wheel. Furthermore, by applying an adjustable and precise force to the pressure plate through the pressurization mechanism, users can flexibly adjust the magnitude of the applied force and the test frequency as needed. At the same time, by utilizing displacement measurement technology (such as the displacement sensor built into the hydraulic cylinder of the actuator or a dial indicator connected directly externally), real-time and accurate monitoring of the displacement of the pressure plate after the force is applied is achieved, providing data support for evaluating the fatigue performance of the nylon guide wheel under different alternating load conditions and meeting complex and ever-changing testing needs.

[0020] 3. This invention employs a movable temperature control box design, making the opening and closing of the temperature control box simple and quick, and improving the convenience of disassembling and testing the nylon wheels. Furthermore, the design of connecting rods with a pressure sensor at one end and contacting the pressure plate surface at the other end via a universal pressure head not only ensures the stability of the loading process but also simplifies the maintenance process and reduces maintenance costs.

[0021] 4. This invention, by adjusting the height of the support frame's crossbeam and the extension length of the driver's hydraulic rod, along with the designed length of the connecting rod, can flexibly adapt to fatigue testing of elevator nylon guide wheels of different specifications and sizes. This height-adjustable design broadens the applicability of the testing device and meets diverse testing needs.

[0022] 5. This invention, through testing under different temperature conditions and alternating load combinations, can comprehensively evaluate the fatigue life, wear, and internal cracks of nylon guide wheels under various working conditions. Simultaneously, it can also conduct comparative tests on different types of elevator pulleys (such as sleeveless nylon pulleys, sleeved nylon pulleys, steel-spoke pulleys, and cast iron pulleys), studying their failure modes and comparing their impact on bearing operating conditions, providing a scientific basis for the optimized design of elevator systems.

[0023] 6. The present invention can also perform static pressure performance tests through a pressurization mechanism. This multi-functional testing capability improves testing efficiency and enables researchers to obtain more comprehensive performance data in a short time. Attached Figure Description

[0024] Figure 1 This is a three-dimensional structural schematic diagram of a fatigue testing device for nylon guide wheels in elevators according to the present invention.

[0025] Figure 2 This is a three-dimensional structural schematic diagram of a fatigue testing device for nylon guide wheels in elevators according to the present invention.

[0026] Figure 3 This is a three-dimensional structural diagram of the pressurization mechanism and testing platform of the present invention.

[0027] Figure 4 This is a three-dimensional structural diagram of the pressurization component and support of the present invention.

[0028] Figure 5 yes Figure 4 The main view.

[0029] Figure 6 This is a three-dimensional structural diagram of the pressurization component of the present invention.

[0030] Figure 7 This is a three-dimensional structural diagram of the support of the present invention.

[0031] Figure 8 This is a three-dimensional structural diagram of the nylon guide wheel of the present invention.

[0032] Figure 9 This is a three-dimensional structural schematic diagram of another embodiment of the pressure plate and nylon guide wheel of the present invention.

[0033] Figure 10 This is a three-dimensional structural schematic diagram of another embodiment of the pressure plate of the present invention.

[0034] Figure 11 This is a three-dimensional structural diagram of the universal pressure head of the present invention.

[0035] Figure 12 This is a three-dimensional structural diagram of the ear seat of the present invention.

[0036] Figure 13 This is a three-dimensional structural diagram of the coupling component of the present invention.

[0037] Among them, 1 is the test platform, 2 is the pressurizing mechanism, 201 is the support frame, 201a is the column, 201b is the crossbeam, 201b1 is the drive port, 202 is the support, 202a is the support plate, 202b is the fixing block, 202b1 is the fixing groove, 203 is the pressurizing assembly, 203a is the connecting rod, 203b is the universal pressure head, 203b1 is the lug, 203b2 is the coupling, 203b3 is the pin, 203c is the pressure plate, 203c1 is the second wheel groove, 203c2 is the clamping plate, and 203d is the pressure sensor. The components are as follows: 3 is the temperature control box, 3a is the test space, 301 is the cover plate, 302 is the box body, 302a is the strip groove, 303 is the support base, 304 is the pulley, 305 is the controller, 306 is the indicator light, 307 is the observation port, 4 is the transmission mechanism, 401 is the slide rail, 402 is the slide groove, 403 is the guide plate, 5 is the nylon guide wheel, 501 is the outer wheel body, 501a is the first wheel groove, 502 is the inner wheel body, 503 is the reinforcing rib, 504 is the steel wire rope, 505 is the bearing, 506 is the shaft, and 507 is the process hole plate. Detailed Implementation

[0038] The following description is merely illustrative in nature and is in no way intended to limit the invention, its application, or use. It will be further understood that the terms “comprising” and / or “including” as used herein specify the presence of the mentioned features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. It will be understood that when an element, component, and / or portion is referred to as “connected to another element, component, and / or portion,” it may be directly connected to another element, component, and / or portion, or there may be intermediate elements. It will be understood that although the terms “first,” “second,” etc., may be used herein to describe various elements, components, and / or portions, these elements, components, and / or portions should not be limited by these terms. These terms are used only to distinguish one element, component, or portion from another element, component, or portion. Therefore, the first element, component, or part discussed below may be referred to as the second element, component, or part without departing from the teachings of the invention. Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having meanings consistent with their meanings in the relevant field and / or the context of this specification, and will not be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0039] It should be understood that, for clarity, the accompanying drawings are not drawn to scale, and the same or similar reference numerals indicate the same or similar parts or components. Furthermore, it should be understood that any embodiments described in this application and the technical features they include can be combined with each other.

[0040] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0041] like Figure 1 and Figure 2As shown, a fatigue testing device for elevator nylon guide wheels includes a test platform 1, a pressurizing mechanism 2, a temperature control box 3, and a transmission mechanism 4. The test platform 1 has a base and a platform fixed to the top of the base. The platform is positioned a certain distance above the ground to create space between the platform and the ground. The platform is used to place the nylon guide wheel 5, the pressurizing mechanism 2, the temperature control box, and the transmission mechanism 4. The internal space of the base can accommodate drive devices, control systems, and other equipment. Both the platform and the base are rectangular structures. The pressurizing mechanism 2 is mounted on the test platform 1 and is used to apply alternating or static loads to the nylon guide wheel 5 to simulate the actual load conditions borne by the nylon guide wheel 5 during elevator operation. The temperature control box is connected to the test platform 1 in a relatively movable manner and forms a test space 3a inside to accommodate the nylon guide wheel 5. The temperature control box is slidably mounted along the length of the test platform 1 and has a roughly rectangular box body 302. The transmission mechanism 4 is connected to the temperature control box, which moves relative to the test platform 1 to open or close, allowing the nylon guide wheel 5 to be placed or removed from the test space 3a. By controlling the temperature conditions within the test space 3a through the temperature control box, and combining this with the alternating load output by the pressurization mechanism 2 to the nylon guide wheel 5, various temperature and load changes encountered by the nylon guide wheel 5 during actual operation can be simulated. The nylon guide wheel can also be other types of elevator pulleys, such as sleeveless nylon pulleys, sleeved nylon pulleys, steel-spoke pulleys, and cast iron pulleys, all of which can be tested using this device.

[0042] like Figure 2-7 As shown, the pressurizing mechanism 2 includes a support frame 201, a support 202, and a pressurizing assembly 203. The support frame 201 is set on the test platform 1 and located outside the temperature control box. The support 202 is located inside the test space 3a and is used to support and fix the nylon guide wheel 5. The pressurizing assembly 203 includes a connecting rod 203a, a universal pressure head 203b, and a pressure plate 203c arranged in series. One end of the connecting rod 203a is set on the support frame 201 and connected to a driver (not shown in the figure). The other end extends downward and enters the test space 3a from the top of the temperature control box. The outer surface of the connecting rod 203a has threads. The bottom of the pressure plate 203c is pressed against the circumferential wall of the nylon guide wheel 5 with a certain wrap angle. The upper surface of the pressure plate 203c is flat, and the flat surface of the pressure plate 203c abuts against the bottom of the universal pressure head 203b. The bottom of the pressure plate 203c is pressed onto the top of the nylon guide wheel 5. Its bottom is arc-shaped and matches the circumferential wall of the nylon guide wheel 5. The bottom of the pressure plate 203c can be constructed into arc-shaped corners of different sizes according to the different sizes of the nylon guide wheels 5. The corner angle α is 90-180 degrees, preferably 90 degrees.

[0043] like Figure 1-3As shown, the support frame 201 includes two uprights 201a mounted on the test platform 1 and a crossbeam 201b slidably mounted between the two uprights 201a for fixing the connecting rod 203a. The distance between the pressure plate 203c and the nylon guide wheel 5 can be adjusted by adjusting the height of the crossbeam 201b. The two uprights 201a are located on opposite outer sides of the temperature control chamber, extending upwards from the test platform 1 to a certain height. The crossbeam 201b is slidably fitted onto the two uprights 201a and positioned above the temperature control chamber. The adjustable height of the crossbeam 201b ranges from 0 to 300 mm.

[0044] In an embodiment not shown, the test platform 1 is also equipped with a hydraulic actuator, which includes a hydraulic cylinder mounted on the test platform 1 and a hydraulic rod telescopically connected to the hydraulic cylinder. The hydraulic rod extends upward from the output end of the hydraulic cylinder to a certain height and is fixedly connected to the end of the crossbeam 201b, so that the hydraulic rod is approximately parallel to the column 201a. The hydraulic cylinder drives the hydraulic rod to extend and retract in the vertical direction, and drives the crossbeam 201b to slide up and down between the two columns 201a to adjust the distance between the pressure plate 203c and the nylon guide wheel 5.

[0045] In an embodiment not shown, a cam bearing follower and a locking nut are provided at the connection between the column 201a and the crossbeam 201b. Once the crossbeam 201b is adjusted to the appropriate position, tightening the locking nut applies pressure to the cam bearing follower, thereby locking the height of the crossbeam 201b. When the position of the crossbeam 201b needs to be adjusted, simply rotate the locking nut in the opposite direction to release the pressure on the cam bearing follower, thus adjusting the height of the crossbeam 201b. After adjustment, tighten the locking nut again to fix the new position.

[0046] like Figure 2-6As shown, the middle part of the crossbeam 201b has a drive port 201b1 for receiving one end of the connecting rod 203a. The actuator (not shown) is connected to one end of the connecting rod 203a through the drive port 201b1. The actuator includes a hydraulic cylinder and a hydraulic rod that is telescopically connected to the hydraulic cylinder. The hydraulic rod passes through the drive port 201b1 and is connected to one end of the connecting rod 203a. One end of the hydraulic cylinder is connected to an external hydraulic system and control system to provide a set static load or alternating load to the hydraulic rod connected to the hydraulic cylinder. A pressure sensor 203d is also configured on the connecting rod 203a to monitor and provide feedback on the pressure applied to the nylon guide wheel 5. The pressure sensor 203d is located at the connection between the hydraulic rod and the connecting rod 203a. The upper end of the pressure sensor 203d is threaded to the hydraulic rod, and the lower end is threaded to the connecting rod 203a. The pressure sensor 203d communicates with an external control system and can collect the thrust output by the hydraulic cylinder in real time, i.e., measure the load acting on the nylon guide wheel 5 in real time. In an embodiment not shown, the connecting rod 203a also has a square block for a wrench holder. The wrench allows the connecting rod 203a to be rotated for disassembly, enabling replacement of connecting rods 203a of different lengths depending on the size of the nylon guide wheel 5.

[0047] like Figure 11-13As shown, the universal pressure head 203b includes a lug 203b1 and a connecting shaft 203b2. The bottom of the lug 203b1 abuts against the pressure plate 203c, and a pin 203b3 is disposed on the lug 203b1. The lower part of the connecting shaft 203b2 is movably connected to the lug 203b1 via the pin 203b3, and the upper part of the connecting shaft 203b2 is detachably connected to the other end of the connecting rod 203a. The detachable connection method can be threaded connection, snap-fit ​​connection, or hinge connection, etc. The connecting shaft 203b2 has a clamping part, the top of which has a sleeve that is threadedly connected to the other end of the connecting rod 203a. The clamping end of the clamping part is movably connected to the pin 203b3 and positioned by a screw bolt. Its clamping force can be adjusted according to the test force and direction. The clamping part and the pin 203b3 form a cross bearing structure to achieve universal rotation. When the actuator begins to apply an alternating load, this periodically changing force first acts on the connecting rod 203a. Since the connecting rod 203a is fixed to the coupling 203b2, the alternating load is transmitted to the coupling 203b2. As the load changes periodically, it is then transmitted through the coupling 203b2 to the lug 203b1, acting on the pressure plate 203c, and finally on the nylon guide wheel. Simultaneously, the coupling 203b2 and the lug 203b1 are movably connected by a pin 203b3, allowing the coupling 203b2 to rotate or oscillate slightly around the pin 203b3 when subjected to alternating loads. This rotation or oscillation further causes the pressure plate 203c and the connected nylon guide wheel 5 to displace relative to each other. Due to the periodic changes in the alternating load, the displacement between the pressure plate 203c and the nylon guide wheel 5 also exhibits periodic changes. This displacement change not only enables the effective application of alternating loads but also allows the entire structure to adapt to changing requirements under different working conditions, ensuring stable system operation and precise control. Furthermore, it should be emphasized that this displacement can be eliminated by fixing the rotation of the nylon guide wheel 5. In this case, the rotation or oscillation of the universal pressure head 203b ensures that the pressure block is fully attached to the outer surface of the nylon guide wheel 5, achieving force balance.

[0048] like Figure 8As shown, the nylon guide wheel 5 includes an outer wheel body 501, an inner wheel body 502, and multiple reinforcing ribs 503. One end of each of the multiple reinforcing ribs 503 is fixed to the inner wheel body 502, while the other end extends and is fixed towards the outer wheel body 501 at a certain angle. A process hole plate 507 is provided between two adjacent reinforcing ribs 503. Multiple first wheel grooves 501a for winding steel wire rope 504 are provided on the circumferential wall of the outer wheel body 501. A bearing 505 is arranged on the inner wheel body 502. A steel inner ring can also be provided between the inner wheel body and the bearing. A shaft 506 is arranged on the bearing 505. Both ends of the shaft 506 are supported on the support 202. The number of first wheel grooves 501a is 4-8. When the drive is started, the generated static or alternating load is transmitted sequentially through the connecting rod 203a, the universal pressure head 203b, and the pressure plate 203c, and acts on the wire rope 504 located on the first wheel groove 501a, and then acts on the nylon guide wheel 5 through the wire rope 504. The bottom of the pressure plate 203c has a second wheel groove 203c1 that mates with the first wheel groove 501a, so that the wire rope 504 wound around the first wheel groove 501a is confined between the first wheel groove 501a and the second wheel groove 203c1.

[0049] like Figure 9 and Figure 10 As shown in the figure, another embodiment of the pressure plate 203c is illustrated. The bottom of the pressure plate 203c has a second wheel groove 203c1 that mates with the first wheel groove 501a. The number of second wheel grooves 203c1 is 4-8. The bottom of the pressure plate 203c has an arc-shaped section and straight sections at both ends of the arc-shaped section. The arc-shaped section mates with the circumferential wall of the nylon guide wheel 5. The steel wire rope 504 is embedded in the second wheel groove 203c1. A clamping plate 203c2 is also provided on the straight section to fix the steel wire rope 504 in the second wheel groove 203c1, acting as a locking mechanism for the steel wire rope 504 in the second wheel groove 203c1, ensuring that the steel wire rope 504 remains stable and does not shift during testing. This configuration eliminates the need to place the steel wire rope 504 in the first wheel groove 501a of the nylon guide wheel 5; instead, the steel wire rope 504 is embedded in the second wheel groove 203c1, simplifying the operation process and improving testing efficiency.

[0050] like Figure 7 As shown, the support 202 has a pair of support plates 202a arranged opposite to each other. The pair of support plates 202a are fixed on the test platform 1 and form a space between them to accommodate the nylon guide wheel 5. A fixing block 202b is arranged on the top of the support plate 202a. The fixing block 202b is connected to the top of the support plate 202a by bolts. The fixing block 202b is provided with a fixing groove 202b1 for mounting the shaft 506 of the nylon guide wheel 5. The fixing groove 202b1 has a V-shaped structure.

[0051] like Figure 1 and Figure 2 As shown, the temperature control box includes a cover plate 301 and a box body 302. The cover plate 301 is set on the test platform 1. One side of the box body 302 is open and slidably connected to the cover plate 301. One side of the box body 302 cooperates with the cover plate 301. The other side of the box body 302 is equipped with a heater (not shown in the figure) for adjusting the temperature of the test space 3a. The bottom of the other side of the box body 302 is equipped with a support base 303 for supporting the box body 302. The support base 303 raises the other side of the box body 302 a certain distance from the ground. The bottom of the support base 303 is equipped with a pulley 304 for driving the box body 302 to move. The outside of the box body 302 is also equipped with a controller 305. The controller 305 is connected to the pressurization mechanism 2, the transmission mechanism 4 and the heater circuit respectively. The bottom of the housing 302 is also open, forming a rectangular through-hole. When the cover 301 and housing 302 are closed, the space enclosed by the cover 301, housing 302, and test platform 1 is the test space 3a. The cover 301 is vertically mounted on the test platform 1. The top of the housing 302 has a U-shaped groove 302a, which is 500-1000mm long and 20-80mm wide, preferably 820mm long and 50mm wide. The groove 302a not only receives and allows the connecting rod 203a to pass through the interior of the test space 3a, but is also equipped with a removable strip plate (not shown in the figure). When the housing 302 is moved to a suitable position, the strip plate covers the groove 302a, effectively reducing heat loss within the test space 3a. In addition, both the cover plate 301 and the housing 302 are equipped with observation ports 307 for observing the nylon guide wheel 5 within the test space 3a. The top of the housing 302 is also equipped with an indicator light 306, which is electrically connected to the controller 305. The indicator light 306 provides visual feedback on the working status of the housing 302 through color and flashing patterns: a red light illuminates when the machine is stopped, a green light flashes intermittently during heating (flashing period is 1 second), and the green light remains constantly on when the set temperature is reached and maintained. The inner wall of the housing 302 is also equipped with an insulation layer to prevent heat loss. The heater heats the gas using resistance wire to regulate the temperature within the test space 3a. The top of the housing 302 has an air inlet with a diameter of 50mm, and the side of the housing has an air outlet with a diameter of 50mm. The air inlet and outlet are connected by an external circulating fan.

[0052] In an embodiment not shown, a temperature sensor is also installed inside the chamber 302. The temperature sensor is connected to both the heater and the controller 305 circuitry to ensure that the temperature within the test space 3a reaches and is maintained at a set value, ranging from 25°C to 100°C. An illumination lamp is also installed inside the chamber 302 for clear observation of the test space 3a. Furthermore, a cooler may be installed inside the chamber 302 to lower the temperature to below 0°C to test the fatigue performance of the nylon guide wheel at low temperatures.

[0053] like Figure 1 and Figure 2 As shown, the transmission mechanism 4 includes a slide rail 401 at the bottom of the cover plate 301 and a slide groove 402 at the bottom of the housing 302. The slide rail 401 moves within the slide groove 402 to control the opening and closing of the cover plate 301 and the housing 302. The bottom of the cover plate 301 has two slide rails 401, and the bottom sides of the housing 302 have two slide grooves 402. Through the interaction of the slide rails 401 and the slide grooves 402, the housing 302 can move freely horizontally, either electrically or manually, with a stroke range of 0-800 mm, facilitating the placement and removal of the nylon guide wheels 5. Furthermore, a guide plate 403 can be configured on the top of the cover plate 301, slidingly connected to the inner top of the housing 302 to achieve a more accurate alignment between the cover plate 301 and the housing 302. In an embodiment not shown, the test platform 1 is also equipped with a limit switch. The limit switch corresponds to the end of the slide rail 401 and senses the sliding position of the housing 302. When the housing 302 slides outward and the end of the slide groove 402 reaches the end of the slide rail 401, it has reached the limit position of the stroke. At this time, the limit switch outputs a signal to the control system, which controls the housing 302 to stop sliding to prevent the slide groove 402 from separating from the slide rail 401.

[0054] In an embodiment not shown, a sliding base plate is also provided at the bottom of the cover plate 301. The sliding base plate is fixed on the test platform 1, and the cover plate 301 is slidably mounted on the sliding base plate. The bottom sides of the box body 302 are slidably connected to the cover plate 301 through guide rods, so that the box body 302 can follow the slide rail trajectory more smoothly during movement, thereby further improving the smoothness and accuracy of the overall operation.

[0055] The method for using the fatigue testing device for elevator nylon guide wheels described above includes the following steps:

[0056] The nylon guide wheel 5 to be tested is fixed on the support 202. The height of the crossbeam 201b in the support frame 201 is adjusted so that the pressure plate 203c of the pressure assembly 203 presses against the circumferential wall of the nylon guide wheel 5 at a certain wrap angle. The temperature control box is moved relative to the test platform 1 by the transmission mechanism 4, thereby closing the test space 3a. The temperature in the test space 3a is adjusted to the preset test temperature by the heater and controller 305 of the temperature control box. The pressure assembly 203 is controlled by the driver to apply alternating load or static load to the nylon guide wheel 5. The pressure sensor 203d is used to monitor and record the pressure value applied to the nylon guide wheel 5. The nylon guide wheel 5 works continuously under the preset test conditions to simulate the fatigue process in actual working conditions.

[0057] The specific testing process is as follows: Test preparation stage: First, turn off the power switch of the temperature control chamber via controller 305 to ensure safe operation. Move the chamber 302 to open the test space 3a, facilitating the installation and fixing of the nylon guide wheel 5 to be tested. Fix the nylon guide wheel 5 onto the support 202, ensuring it is stable and without deviation. Adjust the crossbeam 201b in the support frame 201 to the predetermined height and fix it using the locking mechanism so that the pressure plate 203c of the pressurizing assembly 203 can press against the circumferential wall of the nylon guide wheel 5 with a suitable wrap angle. Install the pressure sensor 203d and its connecting components, including connecting one end of the connecting rod 203a to the lower end of the pressure sensor 203d, and connecting the other end to the universal pressure head 203b, and selecting a pressure plate 203c of appropriate size for installation. A steel wire rope 504 is placed on the first groove 501a of the nylon guide wheel 5, and then the steel wire rope 504 is placed on the second groove 203c1 of the pressure plate 203c one by one to ensure uniform loading.

[0058] Test space 3a enclosure and temperature regulation: The transmission mechanism 4 moves the temperature control chamber relative to the test platform 1, closing the test space 3a. A strip plate is used to cover the strip groove 302a on the top of the chamber 302 to reduce heat loss. The desired test temperature is set on the controller 305 of the temperature control chamber, and the heater is activated to adjust the temperature in the test space 3a to the preset value.

[0059] Loading and Test Execution: The hydraulic rod is extended to an appropriate length by the actuator, ensuring full contact between the universal pressure head 203b and the plane of the pressure plate 203c, thus applying a preset alternating or static load to the nylon guide wheel 5. The pressure sensor 203d monitors and records the pressure value applied to the nylon guide wheel 5 in real time to ensure the accuracy of the test data. The test time and conditions are set to simulate the fatigue process under actual working conditions, allowing the nylon guide wheel 5 to operate continuously under the preset test conditions.

[0060] Experimental observation and evaluation: After a certain period of time, the experiment is stopped, test space 3a is opened, and the surface of the nylon guide wheel 5 is checked for wear or deformation. Further inspection is conducted to check for internal damage such as cracks in the nylon guide wheel 5. The fit between the hole of the nylon guide wheel 5 and the outer ring of the bearing 505 is observed and evaluated to comprehensively determine whether the quality of the nylon guide wheel 5 is up to standard.

[0061] Example 1

[0062] Taking a nylon guide wheel of an elevator as an example, fatigue tests were conducted under different temperatures and alternating loads by outputting a set alternating load through the pressurization mechanism 2 to simulate relatively realistic working conditions and observe the deformation and fatigue cracking of the nylon guide wheel 5. The specific test steps are as follows:

[0063] S1. Calculation of test load:

[0064] When simulating the uniform motion of the elevator, the test load is calculated according to the diameter of the selected nylon guide wheel 5 and the counterweight of the applicable elevator, the weight of the compensation chain suspended on the counterweight, and other parameters.

[0065] When simulating elevator braking and deceleration, the maximum force is taken as the test load, which is 1.8 times the weight of the counterweight and the weight of the compensation chain suspended on the counterweight (its inertial force is calculated based on the maximum deceleration of 0.8gn). The test load applied by the pressurizing mechanism 2 is constant and does not change with the amount of deformation.

[0066] S2. Test Frequency Calculation: One rotation of the simulated nylon guide wheel 5 is considered one cycle; f = v / 2πR, where v is the rope speed and R is the pitch circle radius. For example: if the elevator's rated speed is 1.75 m / s, R = 0.2 m, the test frequency of the nylon guide wheel 5 is f = 2v / 2πR = 2.8, the cycle T = 0.36 s, the test lasts 48 hours, and the number of cycles is 480,000; if the test frequency of the nylon guide wheel 5 is f = v / 2πR = 1.4, the cycle T = 0.72 s.

[0067] S3. Test preparation: Prepare nylon guide wheels 5 for elevators and install them onto support 202 according to the installation requirements of nylon guide wheels 5;

[0068] S4. Temperature setting and preheating: Set the temperature of the temperature control chamber according to the test temperature range, and preheat at the set starting temperature for 4 hours.

[0069] S5. Apply alternating load: After preheating, apply alternating force load at each temperature setting according to the calculation model of alternating force for 48 hours. Monitor the change in radial deformation during the test, record the entire process in high definition, and extend the test time if necessary. Based on the elevator's rated speed of 1.75 m / s, R = 0.2 m, and a nylon guide wheel cycle of 5 cycles T = 0.36 s, a 48-hour test is equivalent to 480,000 cycles; the anti-cord wheel cycle T = 0.72 s, a 48-hour test is equivalent to 240,000 cycles.

[0070] S6. Unload and let stand for 30 minutes. Measure the external dimensions of the nylon guide wheel 5 to determine if there is any deformation, observe whether the nylon guide wheel 5 has any wear or cracks, and observe the fit between the nylon guide wheel hole and the bearing 505.

[0071] S7. If no severe deformation is found, conduct an alternating load fatigue test at the same temperature setting for 48 hours.

[0072] S8. Repeat this process for each round of fatigue testing under alternating loads;

[0073] S9. If any deformation, wear, cracks, or misalignment between the nylon guide wheel hole and bearing 505 are found, record the findings and take photos before ending the test.

[0074] S10. Record the number of cycles and the deformation amount in each cycle.

[0075] For each nylon guide wheel sample, the temperature setting was tested from low to high.

[0076] In summary, the experiment took into account the changes in force during the rotation of the wheel and axle. Based on the rotational speed and the force, the results were converted into the alternating load output by the pressurizing mechanism, which is closer to reality.

[0077] Example 2

[0078] Taking a nylon guide wheel for an elevator as an example, the fatigue test method described above for nylon guide wheels can be used for static pressure tests / static load tests on nylon guide wheels. The specific test steps are as follows:

[0079] S1. Install the nylon guide wheel 5 onto the support 202. Install the steel wire rope 504 on the first groove 501a of the nylon guide wheel 5. The wrap angle of the pressure plate 203c is 90°, and the center of the wrap angle is aligned with the weak point of the nylon guide wheel 5 (such as the weight reduction hole).

[0080] S2. Operate the pressurization mechanism 2 to apply twice the maximum design load force of the nylon guide wheel 5 to the hydraulic rod of the driver, and record the relationship between the force and the amount of deformation.

[0081] S3. Hold the load for 1 minute, measure the deformation after applying the load, and then unload.

[0082] S4. After unloading and letting it stand for 30 minutes, measure the deformation of the nylon guide wheel 5.

[0083] S5. Gradually increase the load force to 10 times the maximum design load force, record the relationship between the force and the deformation, and repeat steps S3 and S4; observe whether the nylon guide wheel 5 body has any fractures or cracks.

[0084] S6. If conditions permit, continue loading until obvious damage first occurs, and record information such as loading force, deformation, duration, and obvious damage location throughout the process.

[0085] In summary, the fatigue testing device for elevator nylon guide wheels of the present invention, by controlling the temperature conditions within the test space through a temperature control chamber and combining the alternating load output to the nylon guide wheel by the pressurizing mechanism, can simulate various temperature and load changes encountered by the nylon guide wheel in actual operation. This highly simulated test environment makes the test results closer to real working conditions, thereby more accurately evaluating the impact of different temperatures and alternating loads on the operating performance of the nylon wheel and its bearings. The pressurizing mechanism of the present invention includes a support frame, a support base, and a pressurizing assembly. The pressurizing assembly includes a connecting rod, a universal pressure head, and a pressure plate arranged in series. It uses steel wire ropes with a specific wrap angle wrapped around the elevator nylon guide wheel as the force transmission medium. These steel wire ropes not only ensure the force balance of each rope on the nylon guide wheel, but also achieve precise positioning and pressure transmission of the steel wire ropes through the second wheel groove on the pressure plate, thereby effectively promoting a tight fit between the steel wire ropes and the nylon guide wheel, strictly adhering to the strict requirements of industry standards for the uniformity of force on the steel wire ropes. This design completely eliminates the slippage or displacement problem between the wire rope and the nylon guide wheel, which is common in traditional rope-pulling tests. This improves the accuracy and reliability of the test and avoids potential deviations in test results caused by nylon guide wheel slippage. Furthermore, by applying an adjustable and precise force to the pressure plate through a pressurizing mechanism, users can flexibly adjust the applied force and test frequency as needed. Simultaneously, by utilizing displacement measurement technology (such as a displacement sensor built into the driver hydraulic cylinder or a directly connected dial indicator), real-time and accurate monitoring of the pressure plate displacement after force application is achieved. This provides data support for evaluating the fatigue performance of the nylon guide wheel under different alternating load conditions, meeting complex and varied testing requirements. The invention employs a movable temperature control box design, making the opening and closing of the temperature control box simple and quick, improving the convenience of disassembling, assembling, and testing the nylon wheel. In addition, the design where one end of the connecting rod is connected to a pressure sensor, and the other end contacts the pressure plate surface through a universal pressure head, not only ensures the stability of the loading process but also simplifies the maintenance process and reduces maintenance costs. This invention, by adjusting the height of the support frame's crossbeam and the extension length of the actuator's hydraulic rod, along with the designed length of the connecting rod, can flexibly adapt to fatigue testing of elevator nylon guide wheels of different specifications and sizes. This height-adjustable design broadens the applicability of the testing device and meets diverse testing needs. This invention conducts tests under different temperature conditions and alternating load combinations, comprehensively evaluating the fatigue life, wear, and internal cracks of nylon guide wheels under various working conditions. Simultaneously, it can also conduct comparative tests on different types of elevator pulleys (such as sleeveless nylon pulleys, sleeved nylon pulleys, steel-spoke pulleys, and cast iron pulleys), studying their failure modes and comparing their impact on bearing operating conditions, providing a scientific basis for the optimized design of elevator systems. This invention can also conduct static pressure performance tests through a pressurization mechanism. This multi-functional testing capability improves testing efficiency, enabling researchers to obtain more comprehensive performance data in a short time.

[0086] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A fatigue testing device for nylon guide wheels in elevators, characterized in that, include: Test platform; A pressurizing mechanism, disposed on the test platform, is used to apply alternating loads or static loads to the nylon guide wheel; wherein the pressurizing mechanism includes: A support frame is mounted on the test platform and located outside the temperature control chamber; A support, located within the test space, is used to support and fix the nylon guide wheel; The pressurizing assembly includes a connecting rod, a universal pressure head, and a pressure plate arranged in series. One end of the connecting rod is mounted on the support frame and connected to a driver, while the other end extends downward and enters the test space from the top of the temperature control chamber. The bottom of the pressure plate is pressed against the circumferential wall of the nylon guide wheel with a wrap angle of 90-180°, and the bottom of the pressure plate is provided with a second groove that mates with the groove of the nylon guide wheel. A temperature control chamber is connected to the test platform in a relatively movable manner, and its interior forms a test space to accommodate the nylon guide wheels; the temperature control chamber includes a cover plate and a chamber body, the cover plate is disposed on the test platform, one side of the chamber body is open and slidably connected to the cover plate to form a closed test space, and the other side of the chamber body is provided with a heater for adjusting the temperature of the test space; A transmission mechanism is connected in conjunction with the temperature control box to drive the temperature control box to move relative to the test platform, thereby opening or closing it, so that the nylon guide wheel can be placed or removed in the test space; the transmission mechanism includes a slide rail disposed at the bottom of the cover plate and a slide groove disposed at the bottom of the box body, and the slide rail moves in the slide groove to control the opening or closing operation of the cover plate and the box body.

2. The fatigue testing device for elevator nylon guide wheels according to claim 1, characterized in that, The connecting rod is also equipped with a pressure sensor to monitor and provide feedback on the pressure applied to the nylon guide wheel.

3. The fatigue testing device for elevator nylon guide wheels according to claim 1, characterized in that, The support frame includes two columns mounted on the test platform and a crossbeam slidably mounted between the two columns for fixing the connecting rod. The distance between the pressure plate and the nylon guide wheel can be adjusted by adjusting the height of the crossbeam.

4. The fatigue testing device for elevator nylon guide wheels according to claim 1, characterized in that, The universal pressure head includes an ear seat and a connecting shaft. The bottom of the ear seat abuts against the pressure plate, and a pin is disposed on the ear seat. The lower part of the connecting shaft is movably connected to the ear seat through the pin, and the upper part of the connecting shaft is detachably connected to the other end of the connecting rod.

5. The fatigue testing device for elevator nylon guide wheels according to claim 1, characterized in that, The nylon guide wheel includes an outer wheel body, an inner wheel body, and multiple reinforcing ribs. One end of each of the multiple reinforcing ribs is fixed to the inner wheel body, while the other end extends and is fixed towards the outer wheel body at a certain angle. A process perforated plate is provided between two adjacent reinforcing ribs. Multiple first wheel grooves for winding steel wire rope are provided on the circumferential wall of the outer wheel body. A bearing is disposed on the inner wheel body, and a shaft is disposed on the bearing. Both ends of the shaft are supported on the support.

6. The fatigue testing device for elevator nylon guide wheels according to claim 1, characterized in that, The bottom of the other side of the box is provided with a support base for supporting the box. The support base raises the other side of the box a certain distance off the ground. The bottom of the support base is provided with pulleys for moving the box. A controller is also provided on the outside of the box.

7. A method for fatigue testing of elevator nylon guide wheels according to any one of the preceding claims, characterized in that, The method includes the following steps: The nylon guide wheel to be tested is fixed on the support, and the height of the crossbeam in the support frame is adjusted so that the pressure plate of the pressure component presses against the circumferential wall of the nylon guide wheel at a certain wrap angle. The temperature control chamber moves relative to the test platform via a transmission mechanism, thereby closing the test space. The temperature control chamber's heater then adjusts the temperature within the test space to the preset test temperature. The pressure assembly is controlled by a driver to apply alternating or static loads to the nylon guide wheel, and the pressure value applied to the nylon guide wheel is monitored and recorded by a pressure sensor. The nylon guide wheel is made to work continuously under preset test conditions to simulate the fatigue process in actual working conditions.

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