一种曳引轮与钢丝绳相配合的当量摩擦系数的测试方法

Abstract

本发明公开了一种曳引轮与钢丝绳相配合的当量摩擦系数的测试方法，包括如下步骤：将曳引轮、导向轮、钢丝绳、第一对重块以及第二对重块布置好后，通过驱动装置驱使曳引轮进行多组运行周期相同的往复旋转运动测试；测量出每次运行周期相同的往复旋转运动中第二对重块的滑移变化量，并计算出每组运行周期相同的往复旋转运动测试中第二对重块的平均滑移变化量；比较得到的第二对重块的平均滑移变化量，如第二对重块的平均滑移变化量产生了突变，停止测试并计算出当前的当量摩擦系数f。本发明的测试方法可以在地面自动实现曳引条件验证以及曳引轮和钢丝绳相配合的当量摩擦系数检测，保证人身安全的情况下还能使得测量的数据更加准确。

Description

Technical Field

[0001] This invention relates to the field of elevator inspection and testing technology, and in particular to a method for testing the equivalent coefficient of friction of the traction sheave and the wire rope. Background Technology

[0002] The traction force of an elevator originates from the friction between the wire rope and the traction sheave groove. Traction performance primarily ensures the dynamic safety of the elevator and is the most basic condition for its operation. The main factors affecting elevator traction force include the performance indicators of the wire rope (diameter, structure, oil content) and the traction sheave groove (material, groove shape, wrap angle, hardness, etc.), as well as the weight difference between the car side and the counterweight side. During the development phase of new elevator models, the equivalent friction coefficient of the traction sheave and wire rope combination for specific designs is tested to assist designers in verifying the elevator's traction conditions.

[0003] Traditionally, the verification of traction conditions and equivalent friction coefficient of elevators mainly relies on the elevator shaft. The verification object is installed in the test shaft to completely simulate the elevator's operating state, controlling the reciprocating motion of the elevator car. Before the test begins, markings are made on the traction sheave and wire rope. After repeated operation, the position of the wire rope slippage on the traction sheave is manually measured to determine the slippage inflection point. The load conditions are recorded, and T1 / T2 and the equivalent friction coefficient are calculated.

[0004] Traditional verification methods mainly suffer from the following problems: high cost of testing equipment, large space requirements, elevator test shaft height is basically 50m or more; manual measurement by personnel, which is labor-intensive; test personnel have to carry counterweights and measure sliding distances in the test shaft, making it difficult to guarantee the safety of the working environment; and long test cycle. Summary of the Invention

[0005] The present invention aims to at least partially solve one of the aforementioned technical problems in the prior art. To this end, embodiments of the present invention provide a method for testing the equivalent friction coefficient of the traction sheave and wire rope, which can automatically verify traction conditions and detect the equivalent friction coefficient of the traction sheave and wire rope on the ground, ensuring personal safety while also making the monitoring data more accurate.

[0006] The method for testing the equivalent coefficient of friction between the traction sheave and the wire rope according to an embodiment of the present invention includes a traction sheave, a guide sheave, a wire rope, a suspension, a first counterweight, and a second counterweight, and further includes the following steps:

[0007] S1. The traction wheel and the guide wheel are rotatably mounted on the suspension, the traction wheel and the guide wheel are spaced apart, one end of the wire rope is connected to the first counterweight, and the other end is wound around the upper side of the traction wheel, then wound around the upper side of the guide wheel and connected to the second counterweight.

[0008] S2. The traction wheel is connected to the drive device, which drives the traction wheel to perform multiple sets of reciprocating rotational motion tests with the same operating cycle. Each set of reciprocating rotational motion tests with the same operating cycle includes multiple reciprocating rotational motions with the same operating cycle. After each set of reciprocating rotational motion tests with the same operating cycle is completed, the mass of the second pair of weights is reduced before the next set of reciprocating rotational motion tests with the same operating cycle is performed.

[0009] S3. Measure the slip change of the second pair of weights in the reciprocating rotational motion with the same running cycle using a displacement sensor, and calculate the average slip change of the second pair of weights in each set of reciprocating rotational motion tests with the same running cycle.

[0010] S4. After each reciprocating rotational motion with the same running cycle, obtain the current operating condition data, using the formula: The current equivalent friction coefficient f is obtained, where a is the wrap angle in radians of the traction sheave, from the formula: The current wrap angle radian a is obtained, T1 is the weight of the first pair of weights, T2 is the weight of the second pair of weights, R is the pitch circle radius of the traction wheel, r is the pitch circle radius of the guide wheel, and W is the center distance between the traction wheel and the guide wheel.

[0011] S5. Compare whether there is a sudden change in the average slip change of the second pair of weights in two adjacent sets of reciprocating rotational motion tests with the same running cycle. If the difference between the average slip change of the second pair of weights in two adjacent sets is less than or equal to the absolute value of the preset threshold, continue to perform the next set of reciprocating rotational motion tests with the same running cycle. If the difference between the average slip change of the second pair of weights in two adjacent sets is greater than the preset threshold, stop the test and record the current working condition data.

[0012] According to the method for testing the equivalent friction coefficient of the traction sheave and the wire rope according to an embodiment of the present invention, in step S2, the reciprocating rotation process with the same running cycle includes driving the traction sheave to rotate clockwise by a first preset angle and then driving the traction sheave to rotate counterclockwise by a second preset angle through the driving device. The first preset angle and the second preset angle are the same in magnitude. The driving device is a motor.

[0013] According to the method for testing the equivalent friction coefficient of the traction sheave and the wire rope according to an embodiment of the present invention, in step S2, the reciprocating rotational motion test with the same running cycle for each group includes performing at least 10 reciprocating rotational motions with the same running cycle.

[0014] According to the method for testing the equivalent friction coefficient of the traction sheave and wire rope according to an embodiment of the present invention, the rising or falling rate of the first counterweight or the second counterweight during the reciprocating rotational motion with the same operating cycle is 2 to 10 m / s.

[0015] According to the method for testing the equivalent coefficient of friction between the traction sheave and the wire rope according to an embodiment of the present invention, the center distance between the traction sheave and the guide sheave is 1500-2500 mm.

[0016] According to the method for testing the equivalent coefficient of friction between the traction sheave and the wire rope according to an embodiment of the present invention, the mass of the first counterweight is greater than the mass of the second counterweight.

[0017] According to the present invention, the method for testing the equivalent coefficient of friction of the traction sheave and the wire rope is described in the following embodiment: the mass of the first counterweight is 200-400 kg, the initial mass of the second counterweight is 200-400 kg, and in step 2, the mass of the second counterweight decreases by 10 kg each time.

[0018] According to the present invention, a method for testing the equivalent coefficient of friction between a traction sheave and a wire rope is provided, wherein the pitch circle radius of the traction sheave is greater than that of the guide sheave, wherein the pitch circle radius of the traction sheave is 400-1000 mm and the pitch circle radius of the guide sheave is 300-800 mm.

[0019] According to an embodiment of the present invention, a method for testing the equivalent coefficient of friction between a traction sheave and a wire rope is provided, wherein the diameter of the wire rope is 8 to 16 mm.

[0020] According to the method for testing the equivalent friction coefficient of the traction sheave and wire rope according to an embodiment of the present invention, the lifting height of the first counterweight or the second counterweight in the same reciprocating rotational motion test process of one running cycle is 6 to 20 m.

[0021] Based on the above technical solution, the embodiments of the present invention have at least the following beneficial effects: 1. The testing method of the present invention no longer relies on elevator shaft facilities, and the verification and testing of elevator traction conditions and the equivalent friction coefficient of the traction sheave and wire rope can be achieved on the ground, reducing test costs and improving test efficiency; 2. The test process can simulate and verify whether the elevator traction conditions meet the requirements by adjusting the counterweight or adjusting the wrap angle of the traction sheave; 3. During the test, the movement of the traction sheave is automatically controlled and data is automatically collected, which can accurately determine the slip point and automatically calculate the equivalent friction coefficient of the traction sheave and wire rope, greatly reducing the labor intensity of test personnel and improving work safety; 4. Verifying traction conditions and measuring the equivalent friction coefficient under dynamic conditions can more closely approximate the actual operating state of the elevator and more comprehensively evaluate the value of the equivalent friction coefficient. It should be noted that the first counterweight simulates the counterweight weight of the elevator in actual use, and the second counterweight simulates the weight of the elevator car under different working conditions. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments;

[0023] Figure 1 This is a schematic diagram of the layout of the traction sheave, guide sheave, wire rope, first counterweight and second counterweight in the suspension in an embodiment of the present invention;

[0024] Figure 2 This is a graph showing the change in the sliding distance of the second pair of counterweights in an embodiment of the present invention. Detailed Implementation

[0025] This section will describe in detail specific embodiments of the present invention. Preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but they should not be construed as limiting the scope of protection of the present invention.

[0026] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0027] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0028] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0029] Traditional methods for verifying elevator traction conditions mainly suffer from problems such as high cost of testing equipment, large space requirements (elevator test shafts are typically 50m high or more), manual measurement by personnel, high labor intensity, difficulty in ensuring the safety of the working environment when personnel are moving counterweights and measuring sliding distances in the test shaft, and long test cycles.

[0030] Therefore, this invention provides a method for testing the equivalent coefficient of friction between the traction sheave 100 and the wire rope 300, the specific steps of which are as follows:

[0031] Reference Figure 1 A traction sheave 100, a guide wheel 200, a wire rope 300, a first counterweight 400, and a second counterweight 500 are installed on the suspension 800. A control cabinet 900 is installed next to the suspension 800. The traction sheave 100 and the guide wheel 200 are rotatably mounted on the suspension 800 and are spaced apart. One end of the wire rope 300 is connected to the first counterweight 400, and the other end is wound around the upper side of the traction sheave 100, then around the upper side of the guide wheel 200, and then connected to the second counterweight 500.

[0032] During the setup and preparation process required for testing, the arrangement of relevant components should meet the following conditions: the center distance between the traction sheave 100 and the guide sheave 200 is 1500-2500mm; the horizontal distance between the traction sheave 100 and the guide sheave 200 is determined based on the size and wrap angle of the traction sheave 100 and the guide sheave 200, ensuring that the traction sheave 100 and the guide sheave 200 do not interfere; the mass of the first pair of counterweights 400 is 200-400kg; the initial mass of the second pair of counterweights 500 is 200-400kg; the mass of the first pair of counterweights 400 should be greater than the mass of the second pair of counterweights 500; the pitch circle radius of the traction sheave 100 is greater than the pitch circle radius of the guide sheave 200; the pitch circle radius of the traction sheave 100 is 400-1000mm; the pitch circle radius of the guide sheave 200 is 300-800mm; and the diameter of the wire rope 300 is 8-16mm.

[0033] After the necessary setup for testing is completed, the traction sheave 100 is connected to the drive unit 700, and the control cabinet 900 is electrically connected to the drive unit 700. The control cabinet 900 issues commands to operate the drive unit 700, driving the traction sheave 100 to perform multiple sets of reciprocating rotational motion tests with the same operating cycle. Each set of reciprocating rotational motion tests with the same operating cycle includes multiple reciprocating rotational motions with the same operating cycle. After each set of reciprocating rotational motion tests with the same operating cycle is completed, the mass of the second counterweight 500 is reduced before the next set of reciprocating rotational motion tests with the same operating cycle is performed. It should be noted that one reciprocating rotational motion process with the same operating cycle includes driving the traction sheave 100 to rotate clockwise by a first preset angle and then driving the traction sheave 100 to rotate counterclockwise by a second preset angle. That is, the traction sheave 100 first rotates clockwise and then counterclockwise, which constitutes one reciprocating rotational motion with the same operating cycle. In the reciprocating rotational motion with the same operating cycle, the first preset angle and the second preset angle are the same size. The drive unit 700 is preferably a motor. In addition, to make the simulated data more accurate and reliable and closer to the actual operating conditions of the elevator, each set of reciprocating rotational motion tests with the same operating cycle includes at least 10 reciprocating rotational motions with the same operating cycle. The mass of the second pair of weights 500 is reduced by 10 kg each time, and the rising or falling rate of the first pair of weights 400 or the second pair of weights 500 during the reciprocating rotational motion with the same operating cycle is 2 to 10 m / s.

[0034] During each reciprocating rotation of the traction sheave 100 with the same operating cycle, the displacement sensor 600 measures the slip change of the second pair of counterweights 500. The displacement sensor 600 is electrically connected to the control cabinet 900. After each set of reciprocating rotation tests with the same operating cycle is completed, the average slip change of the second pair of counterweights 500 during each set of reciprocating rotation tests is calculated. It should be noted that the lifting height of the first pair of counterweights 400 or the second pair of counterweights 500 during one reciprocating rotation process with the same operating cycle is between 6 and 20 meters.

[0035] Furthermore, after each identical reciprocating rotational motion, the current operating condition data is obtained, as shown by the formula: The current equivalent friction coefficient f is obtained, where a is the wrap angle in radians of the traction sheave 100, from the formula: The current wrap angle radian a is obtained, T1 is the weight of the first pair of counterweights 400, T2 is the weight of the second pair of counterweights 500, R is the pitch circle radius of the traction sheave 100, r is the pitch circle radius of the guide sheave 200, and W is the center distance between the traction sheave 100 and the guide sheave 200. The equivalent friction coefficient f of the traction sheave 100 and the wire rope 300 after each reciprocating rotational motion with the same running cycle is calculated by the formula obtained from the summary.

[0036] After completing multiple sets of reciprocating rotational motion tests with the same operating cycle, compare the average slip change of the second counterweight 500 in two adjacent sets of reciprocating rotational motion tests with the same operating cycle to see if there is an abrupt change. If the difference in the average slip change of the second counterweight 500 in two adjacent sets is less than or equal to the absolute value of the preset threshold, continue with the next set of reciprocating rotational motion tests with the same operating cycle. If the difference in the average slip change of the second counterweight 500 in two adjacent sets is greater than the preset threshold, stop the test and record the current working condition data. The T1 / T2 ratio at this time is a more suitable ratio of the weight of the elevator counterweight to the weight of the elevator car. The equivalent friction coefficient f calculated under this test condition for the traction sheave 100 and the wire rope 300 is also a more accurate equivalent friction coefficient f. Among them, the difference in the average slip change of the second counterweight 500 in two adjacent sets without slip abrupt changes is used as the benchmark, and the preset threshold is 5 to 10 times the difference in the average slip change of the second counterweight 500 in two adjacent sets without slip abrupt changes.

[0037] It should be noted that the slip change of the second pair of weights 500 must be measured under the condition that the wire rope 300 does not slip. On this basis, if there is a significant increase in the average slip change of the second pair of weights 500 in two adjacent groups of reciprocating rotational motion tests with the same running cycle, it can be determined that a slip change has occurred. For example, if there is no slip change in multiple groups of reciprocating rotational motion tests with the same running cycle, the absolute value of the difference between the average slip change of the second pair of weights 500 in multiple adjacent groups should be 2 to 3 mm. When the weight of the second pair of weights 500 decreases or increases in the next group of reciprocating rotational motion tests with the same running cycle, the absolute value of the difference between the average slip change of the second pair of weights 500 measured at this time and the average slip change of the second pair of weights 500 in the previous group suddenly changes to 10 mm, which can be considered as a sudden change in the average slip change of the second pair of weights 500 in this state.

[0038] During the above test, the traction sheave 100 is driven by a motor to achieve reciprocating linear motion. An angle sensor, a tension sensor, and a displacement sensor 600 are used in conjunction to automatically collect the rotation angle of the traction sheave 100, the tension on the wire rope 300, and the slippage change of the second counterweight 500. By adjusting the mass of the second counterweight 500, the load change of the elevator car is simulated, and the ratio of T1 / T2 and the equivalent friction coefficient f of the traction sheave 100 and the wire rope 300 can be calculated quickly and effectively.

[0039] Compared to existing technologies, the testing method of this invention no longer relies on elevator shaft facilities. It can verify and test the elevator traction conditions and the equivalent friction coefficient of the traction sheave 100 and the wire rope 300 on the ground, reducing testing costs and improving testing efficiency. The testing process can simulate and verify whether the elevator traction conditions meet the requirements by adjusting the counterweight or the wrap angle of the traction sheave 100. During the test, the movement of the traction sheave 100 is automatically controlled and data is automatically collected. The slip point can be accurately determined, and the equivalent friction coefficient of the traction sheave 100 and the wire rope 300 can be automatically calculated, which greatly reduces the labor intensity of the test personnel and improves work safety. Verifying the traction conditions and measuring the equivalent friction coefficient under dynamic conditions can more closely approximate the actual operating state of the elevator and more comprehensively evaluate the value of the equivalent friction coefficient.

[0040] It should be noted that the first counterweight 400 simulates the counterweight weight of the elevator in actual operation, while the second counterweight 500 simulates the weight of the elevator car under different operating conditions. The maximum weight of the elevator car is under full load conditions, where the weight of the elevator car will exceed the weight of the elevator counterweight. In this case, it is necessary to consider swapping the positions of the first and second counterweights 400 and 500 to conduct traction condition tests. The minimum weight is under no-load conditions. When designing a new elevator model, the extreme values ​​of T1 / T2 are determined based on the elevator's dimensions and materials. The combination scheme of the traction sheave 100 and wire rope 300 is selected based on the extreme values ​​of T1 / T2 to ensure that the elevator design meets the traction conditions.

[0041] This embodiment also provides a preferred test setup implementation scheme, with the following specific settings: the pitch circle radius of the traction sheave 100 is 600mm, the pitch circle radius of the guide sheave 200 is 480mm, the center distance between the traction sheave 100 and the guide sheave 200 is 2000mm, the rising or falling speed of the first pair of counterweights 400 or the second pair of counterweights 500 during the reciprocating rotational motion test with the same running cycle is 2m / s, the mass of the first pair of counterweights 400 is 280kg, the initial mass of the second pair of counterweights 500 is 250kg, and the diameter of the wire rope 300 is 10mm. After the above settings are completed, the test is started, and the test results are shown in the table below and plotted as shown in the figure. Figure 2The following is a graph showing the change in the sliding distance of the second pair of counterweights 500:

[0042]

[0043] From the above table and Figure 2 It can be seen that when the weight of the second pair of weights 500 is reduced to 200kg, the absolute value of the difference between the average slip change of the second pair of weights 500 in the sixth group and the average slip change of the second pair of weights 500 in the previous group is 9.8mm. In the data of the first five groups, the slip increment of the average slip change of the second pair of weights 500 in adjacent groups does not exceed the range of 0-2mm. In the sixth group, the slip increment of the average slip change of the second pair of weights 500 reaches 9.8mm, which is about 5 times the original value, thus identifying the point of abrupt slip change. In the sixth group of data, T1 = 280 × 9.8 = 2744N, T2 = 200 × 9.8 = 1960N, R = 0.6m, r = 0.48m, W = 2m. Substituting the above relevant data into the formula... The current wrap angle in radians is calculated to be a = 1.72. Substituting the obtained wrap angle in radians a and related data into the formula: The current equivalent friction coefficient f = 0.196 is obtained. The calculated T1 / T2 and equivalent friction coefficient f can support the actual design work and thus guide the actual design work of elevators.

[0044] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for testing the equivalent coefficient of friction of a traction sheave and a wire rope, comprising a traction sheave (100), a guide sheave (200), a wire rope (300), a suspension (800), a first counterweight (400), and a second counterweight (500), characterized in that, Includes the following steps: S1. The traction sheave (100) and the guide sheave (200) are rotatably mounted on the suspension (800). The traction sheave (100) and the guide sheave (200) are spaced apart. One end of the wire rope (300) is connected to the first counterweight (400), and the other end is wound around the upper side of the traction sheave (100), then wound around the upper side of the guide sheave (200), and then connected to the second counterweight (500). The mass of the first counterweight (400) is 200~400kg, and the initial mass of the second counterweight (500) is 200~400kg. S2. The traction wheel (100) is connected to the drive device (700). The drive device (700) drives the traction wheel (100) to perform multiple sets of reciprocating rotational motion tests with the same running cycle. Each set of reciprocating rotational motion tests with the same running cycle includes multiple reciprocating rotational motions with the same running cycle. Each set of reciprocating rotational motion tests with the same running cycle includes performing at least 10 reciprocating rotational motions with the same running cycle. After each set of reciprocating rotational motion tests with the same running cycle is completed, the mass of the second pair of weights (500) is reduced before the next set of reciprocating rotational motion tests with the same running cycle is performed. The mass of the second pair of weights (500) is reduced by 10 kg each time. The mass of the first pair of weights (400) is greater than the mass of the second pair of weights (500). The rising or falling rate of the first pair of weights (400) or the second pair of weights (500) during the reciprocating rotational motion with the same running cycle is 2~10 m / s. S3. The displacement sensor (600) measures the slip change of the second pair of weights (500) in the reciprocating rotational motion with the same running cycle in each cycle, and calculates the average slip change of the second pair of weights (500) in each set of reciprocating rotational motion tests with the same running cycle. S4. After each reciprocating rotational motion with the same running cycle, obtain the current operating condition data, using the formula: The current equivalent friction coefficient f is obtained, where a is the wrap angle radians of the traction sheave (100), from the formula: The current wrap angle in radians 'a' is obtained. For the weight of the first pair of weights (400), R is the weight of the second pair of weights (500), R is the pitch circle radius of the traction wheel (100), r is the pitch circle radius of the guide wheel (200), and W is the center distance between the traction wheel (100) and the guide wheel (200). S5. Under the condition that the wire rope (300) does not slip, compare the average slip change of the second pair of weights (500) in two adjacent sets of reciprocating rotational motion tests with the same running cycle to see if there is a sudden change. If the difference between the average slip change of the second pair of weights (500) in two adjacent sets is less than or equal to the absolute value of the preset threshold, continue to perform the next set of reciprocating rotational motion tests with the same running cycle. If the difference between the average slip change of the second pair of weights (500) in two adjacent sets is greater than the preset threshold, stop the test and record the current working condition data.

2. The method for testing the equivalent coefficient of friction between the traction sheave and the wire rope according to claim 1, characterized in that: In step S2, the reciprocating rotation process with the same running cycle includes driving the traction wheel (100) to rotate clockwise by a first preset angle through the driving device (700) and then driving the traction wheel (100) to rotate counterclockwise by a second preset angle. The first preset angle and the second preset angle are the same size. The driving device (700) is a motor.

3. The method for testing the equivalent coefficient of friction between the traction sheave and the wire rope according to claim 1, characterized in that: The center distance between the traction sheave (100) and the guide sheave (200) is 1500~2500mm.

4. The method for testing the equivalent coefficient of friction between the traction sheave and the wire rope according to claim 1, characterized in that: The pitch circle radius of the traction sheave (100) is greater than that of the guide sheave (200), wherein the pitch circle radius of the traction sheave (100) is 400~1000mm and the pitch circle radius of the guide sheave (200) is 300~800mm.

5. The method for testing the equivalent coefficient of friction between the traction sheave and the wire rope according to claim 1, characterized in that: The diameter of the wire rope (300) is 8~16mm.

6. The method for testing the equivalent coefficient of friction between the traction sheave and the wire rope according to claim 1, characterized in that: The lifting height of the first counterweight (400) or the second counterweight (500) during a reciprocating rotational motion test with the same running cycle is 6~20m.

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