A stress following detection method for elevator guide rails

Abstract

The present invention relates to the technical field of elevator guide rails, and in particular to a stress tracking detection method for elevator guide rails, comprising the following detection steps: S1 obtaining basic parameters of the guide rail car, S2 calculating the overturning moment of the car, S3 selecting two force-bearing points on the guide rail and calculating the forces received at the two force-bearing points, S4 respectively calculating the deformation displacements at the two force-bearing points, and respectively obtaining calculation formulas between the two deformation displacements and the forces, S5 obtaining the relationship between the overturning angle of the guide rail and the deformation displacements of the two force-bearing points; S6 obtaining the relationship between the overturning angle of the guide rail and the forces received at the two force-bearing points, S7 respectively calculating the bending moments received at the two force-bearing points, and obtaining the relationship between the maximum bending moment and the force F; S8 obtaining the relationship between the bending stress and the overturning angle; the present invention is used to overcome the problem that the prior art cannot detect the degree of deformation of the guide rail according to the real-time operation of the elevator guide rail. The present invention can detect whether the elevator is running smoothly and safely according to the real-time operation status of the guide rail, thereby improving the safety of riding the elevator.

Description

Technical Field

[0001] The present invention relates to the technical field of elevator guide rails, and in particular to a stress following detection method for elevator guide rails. Background Art

[0002] With the advancement of urban development, elevators are a common means of lifting and operating in our lives, providing convenience for people's lives and work. Among them, elevator guide rails are important components used to support and guide the elevator car, and determine whether the elevator is safe, comfortable, and operates stably at high speed. Therefore, during elevator operation, the stress state detection of the elevator guide rails is one of the important matters to ensure the safe operation of the elevator.

[0003] When the elevator is in operation, the guide rails mainly carry the car and the counterweight. When the car vibrates or experiences abnormal operation, the guide rails will be subjected to deflection force, which will affect the verticality of the guide rails, and then affect the safe and smooth operation of the subsequent car. There is a serious safety hazard. In the existing technology, the guide rails are mostly subjected to force analysis and pre-testing when the guide rails are selected before the elevator is put into installation and use. There is a lack of real-time monitoring of the stress status of the guide rails after the elevator is put into use. It is impossible to detect the deformation degree of the guide rails according to the real-time operation of the guide rails, and it is impossible to provide effective protection for the safe operation of the elevator. Summary of the Invention

[0004] In order to overcome the above-mentioned defects in the prior art, the present invention provides a stress tracking detection method for elevator guide rails, which can effectively detect whether the elevator is running smoothly and safely according to the real-time operating status of the guide rails, thereby improving the safety of elevator riding.

[0005] To solve the above technical problems, the present invention adopts a technical solution: a stress tracking detection method for elevator guide rails, comprising the following detection steps:

[0006] S1: Establish a guide rail car model and obtain basic parameters of the guide rail car, including the car's deadweight G and the offset e of the car's center of gravity relative to the suspension center;

[0007] S2: Calculate the car's overturning moment M based on the basic parameters obtained c , get M c =Ge;

[0008] S3: Select two force points on the guide rail, with the distance between the two force points being h, and calculate the force F at the two force points. According to the guide rail force balance relationship, the moment at the force points is equal to the overturning moment M of the car. c , and then according to the moment calculation formula, the overturning moment M of the car is obtained c The calculation relationship between i1 and force F is:

[0009] 2Fh=M c ;

[0010] S4: Calculate the deformation displacements ω1 and ω2 at the two force points respectively. According to the approximate differential equation of the simply supported beam deflection curve in material mechanics and the superposition principle of bending deformation, the calculation relationship i2 between ω1 and force F and the calculation relationship i3 between ω2 and force F are obtained respectively.

[0011] S5: Calculate the overturning angle θ of the guide rail and obtain the calculation relationship i4 between the overturning angle θ of the guide rail and the deformation displacement of the two force points:

[0012]

[0013] S6: Combine steps S1-S5, and express the deformation displacements ω1 and ω2 in the calculation relationship i4 using the force F, to obtain the calculation relationship i5 between the overturning angle θ of the guide rail and the force F at the two force points;

[0014] S7: Calculate the bending moments M1 and M2 at the two stress points respectively, and take the maximum bending moment M between the two stress points. m =max(M1,M2), get the maximum bending moment M m The calculation relationship between the force F is formula i6;

[0015] S8: Calculate the bending stress σ on the guide rail m , according to the bending stress calculation formula, the bending stress σ is obtained m The calculation relationship between the overturning angle θ and the force F is substituted into the bending stress σ m In the calculation, the bending stress σ is obtained m The calculation relationship between the overturning angle θ and the bending stress σ of the guide rail can be calculated by real-time monitoring of the overturning angle θ. m , which makes it easy to monitor the deformation of the guide rail and ensure that the guide rail operates within a safe range.

[0016] Furthermore, in step S3, the two force-bearing points are the positions of the two guide shoes on the guide rail, namely position point A and position point B, wherein the distance between the two guide rail brackets is l, and the distance between position point A and the adjacent guide rail bracket is a;

[0017] Simplify the guide rail car model, calculate the deformation displacement ω1 of position point A and the deformation displacement ω2 of position point B in step S4, and calculate the following calculation results using the calculation formula i2 and the calculation formula i3:

[0018]

[0019]

[0020] Where E is the elastic modulus of the selected guide rail, and I is the moment of inertia of the selected guide rail.

[0021] Furthermore, the calculation relationship i5 in step S6 is:

[0022]

[0023] Furthermore, in step S7, the steps for calculating the bending moments at the two force-bearing points are as follows:

[0024] S7.1: The two brackets on the guide rail are located at position C and position D respectively. From the force balance relationship, we can get F C =F D , taking point C as the center of the rotation axis, according to the moment balance relationship Fa-F(h+a)+F D l=0, we get F C =F D =Fh / l;

[0025] S7.2: Calculate the moment M between position C and position A respectively CA , the torque M between position point A and position point B AB , the torque M between position point B and position point D BD , find the position of maximum bending moment on the guide rail.

[0026] Furthermore, in step S7.2, the torque calculation results between the positions are as follows:

[0027] M CA =(Fh / l)x,(0≤x≤a);

[0028] M AB =(Fh / l)xF(xa),(a≤x≤a+h);

[0029] M BD =-(Fh / l)(lx),(a+h≤x≤l);

[0030] Where x represents the distance between the bending moment calculation point and position point C.

[0031] Furthermore, according to the calculation results in step S7.2, the maximum bending moment position on the guide rail is at position A or position B, and the maximum bending moment M between the two positions is taken. m =max(M1,M2), get the maximum bending moment M m The calculation relationship between i6 and force F is as follows:

[0032] When 2a+hl>0,

[0033] When 2a+hl<0,

[0034] Furthermore, the bending stress calculation formula in step S8 is σ m =M m / W, where W represents the bending section coefficient.

[0035] Furthermore, in step S8, when 2a+hl>0, the maximum bending moment M m The calculation relationship between i7 and force F is as follows:

[0036]

[0037] Furthermore, in step S8, when 2a+hl<0, the maximum bending moment M m The calculation relationship between i7 and force F is as follows:

[0038]

[0039] Furthermore, the tilting angle θ of the guide rail is measured by a digital inclinometer installed on the elevator.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] The stress tracking detection method for elevator guide rails provided by the present invention first analyzes the deformation coordination relationship between the guide rails and the car, calculates the relationship between the elevator inclination and the load on the elevator guide rails, then calculates the bending moment of the guide rails based on a simplified elevator guide rail model, calculates the bending stress of the elevator guide rails using selected elevator guide rail parameters of a corresponding model, and derives the relationship between the elevator inclination and the bending stress on the guide rails. The stress on the guide rails can be converted in real time by simply recording the elevator inclination in real time, ensuring that the guide rails operate within a safe range. There is no need to re-modify elevators that have already been put into use, and the method is low in cost and effective. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Attachment Figure 1 This is a structural diagram of the installation of guide rails and car in an elevator;

[0043] Attachment Figure 2 This is a schematic diagram of the overturning moment generated when the car and guide rails shake;

[0044] Attachment Figure 3 This is the principle diagram of the deformation of the guide rail;

[0045] Attachment Figure 4 Schematic diagram for calculating the overturning angle of the guide rail;

[0046] Attachment Figure 5 This is a structural diagram of measuring the overturning angle of a guide rail using a digital inclinometer;

[0047] Attachment Figure 6The figure is a flow chart for calculating the relationship between the overturning angle of the guide rail and the bending stress of the guide rail according to the present invention.

[0048] Reference numerals: 1 - guide rail; 2 - car; 3 - guide shoe; 310 - position point A; 320 - position point B; 4 - bracket; 410 - position point C; 420 - position point D; 5 - traction rope; 6 - digital inclinometer. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The present invention is described in one of the embodiments below in combination with the specific implementation methods. Among them, the drawings are only for illustrative purposes and represent only schematic diagrams rather than physical drawings, and cannot be understood as limitations on this patent; in order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0050] A stress following detection method for elevator guide rails, such as Figure 6 As shown, the following detection steps are included:

[0051] S1: If Figure 1 As shown, a guide rail car model is established to obtain basic parameters of the guide rail car, including the weight G of the car 2 and the offset e of the center of gravity of the car 2 relative to the suspension center;

[0052] S2: If Figure 2 As shown, when the car 2 is running, the car 2 is suspended by the traction rope 55. Since the center of gravity of the car 2 is offset from the suspension center by an amount e, the car 2 will generate a tipping moment M c , calculate the overturning moment M of car 2 based on the basic parameters obtained in step S1 c , get M c =Ge;

[0053] S3: If Figure 2 As shown, two force points are selected on the guide rail 1, and the distance between the two force points is h. The force F at the two force points is calculated. According to the guide rail force balance relationship, the torque applied to the guide rail 1 and the overturning torque generated by the car 2 are in equilibrium. Therefore, the torque at the force point of the guide rail 1 is equal to the overturning moment M of the car 2. c , and then according to the moment calculation formula, we can get the overturning moment M of car 2 c The calculation relationship between i1 and force F is:

[0054] 2Fh=M c ;

[0055] S4: As Figure 3 As shown, the guide rail car model is simplified, and according to the approximate differential equation of the simply supported beam deflection curve in material mechanics and the superposition principle of bending deformation, the deformation displacements ω1 and ω2 at the two force points are calculated respectively, and the calculation relationship i2 between ω1 and force F and the calculation relationship i3 between ω2 and force F are obtained respectively;

[0056] It should be noted that, in this embodiment, in order to facilitate the measurement of the basic parameters of the guide rail 1, the two force points in step S3 are preferably the positions of the two guide shoes 3 on the guide rail 1, namely Figure 2 At the middle position point A and position point B, at the same time, the distance between the two brackets 4 of the guide rail 1 is measured as l, and the distance between the position point A and the adjacent guide rail 1 bracket 4 is a;

[0057] like Figure 3 As shown, the guide rail car model is simplified, and the deformation displacement ω1 of position point A and the deformation displacement ω2 of position point B in step S4 are calculated to obtain:

[0058] Calculate the relationship i2:

[0059] Calculate the relationship i3:

[0060] Wherein, E is the elastic modulus of the selected guide rail 1, and I is the moment of inertia of the selected guide rail 1.

[0061] S5: If Figure 4 As shown in the figure, A' and B' respectively represent the positions of position point A and position point B after the guide rail 1 is deformed by force. The deformation of position point A and position point B is very small. According to the deformation coordination relationship between the guide rail and the car, the deformation overturning angle θ of the guide rail 1 is calculated using trigonometric functions and other calculation formulas, and the calculation relationship between the overturning angle θ of the guide rail 1 and the deformation displacement of the two force points is obtained. Formula i4:

[0062]

[0063] S6: Combine steps S1-S5, and express the deformation displacements ω1 and ω2 in the calculation relationship i4 using the force F, to obtain the calculation relationship i5 between the overturning angle θ of the guide rail 1 and the force F at the two force points;

[0064]

[0065] S7: Calculate the bending moments M1 and M2 at the two stress points respectively, and take the maximum bending moment M between the two stress points. m =max(M1,M2), get the maximum bending moment M m The calculation relationship between the force F is formula i6;

[0066] It should be noted that in step S7, the steps for calculating the bending moments at the two force points are as follows:

[0067] S7.1: The positions of the two brackets 4 on the guide rail 1 are respectively at position C and position D. From the force balance relationship, we can get F C =F D , taking point C as the center of the rotation axis, according to the moment balance relationship Fa-F(h+a)+F D l=0, we get F C =F D =Fh / l;

[0068] S7.2: Calculate the moment M between position C and position A respectively CA , the torque M between position point A and position point B AB , the torque M between position point B and position point D BD , find the position of maximum bending moment on guide rail 1.

[0069] Furthermore, in step S7.2, the torque calculation results between the positions are as follows:

[0070] M CA =(Fh / l)x,(0≤x≤a);

[0071] M AB =(Fh / l)xF(xa),(a≤x≤a+h);

[0072] M BD =-(Fh / l)(lx),(a+h≤x≤l);

[0073] Among them, x represents the distance between the bending moment calculation point and the position point C. By calculating the bending moment of each point, the entire bending moment distribution is obtained and the maximum bending moment position is obtained.

[0074] Furthermore, according to the calculation result in step S7.2, the maximum bending moment position on the guide rail 1 is at position A or position B, and the maximum bending moment M between the two positions is taken. m =max(M1,M2), get the maximum bending moment M m The calculation relationship between i6 and force F is as follows:

[0075] When 2a+hl>0,

[0076] When 2a+hl<0,

[0077] S8: Calculate the bending stress σ on guide rail 1 m , according to the bending stress calculation formula, the bending stress σ is obtained mThe calculation relationship between the overturning angle θ and the force F is substituted into the bending stress σ m In the calculation, the bending stress σ is obtained m The calculation relationship between the overturning angle θ and the bending stress σ of the guide rail 1 can be calculated by real-time monitoring of the overturning angle θ of the guide rail 1. m , which makes it easy to monitor the deformation degree of the guide rail 1, thereby ensuring that the guide rail 1 operates within a safe range.

[0078] It should be noted that the bending stress calculation formula in step S8 is σ m =M m / W, where W represents the bending section coefficient.

[0079] When 2a+hl>0, the maximum bending moment M m The calculation relationship between i7 and force F is as follows:

[0080]

[0081] When 2a+hl<0, the maximum bending moment M m The calculation relationship between i7 and force F is as follows:

[0082]

[0083] Therefore, according to the calculation formula i7, it can be concluded that there is no need to refit the elevator that has been put into use. The bending stress σ of the guide rail 1 can be converted by real-time monitoring of the overturning angle θ of the guide rail 1. m By detecting the real-time force condition of the guide rail 1, the guide rail 1 can be operated within a safe range, thereby ensuring the stable operation of the elevator. In addition, the elevator guide rail 1 can be inspected and maintained in real time based on the real-time force detection of the guide rail 1, thereby reducing the failure rate of the elevator operation and ensuring safe use.

[0084] Furthermore, in order to facilitate the detection of the overturning angle of the guide rail 1, in this embodiment, a digital inclinometer 6 is preferably installed on the elevator, and the overturning angle θ of the guide rail 1 is detected in real time by the digital inclinometer 6.

[0085] Compared with the existing technology, the current analysis of the stress condition of the elevator guide rail 1 mostly stops at the strength verification when the guide rail 1 is selected. There is a lack of real-time monitoring of the stress state of the guide rail 1 after the elevator is put into use. It is impossible to detect the deformation degree of the guide rail 1 according to the real-time operation of the guide rail 1, and it is impossible to provide effective protection for the safe operation of the elevator. In addition, the stress analysis process of the elevator guide rail 1 in the existing technology is complicated and the calculation is cumbersome. Usually, two detection rollers are respectively set at the two ends of the relative deformation of the elevator guide rail 1. The two detection rollers are in contact with the surface of the elevator guide rail 1, and there is an initial pressure on the detection rollers. Since the two detection rollers are set at the two ends of the relative deformation, if the elevator guide rail 1 deforms to one end, the other end will By detecting the pressure changes on the two detection rollers, the deformation of the guide rail 1 in this direction can be detected. By establishing a coordinate system and drawing the pressure change curve on the coordinate system, the deformation of the elevator guide rail 1 at each position in this direction can be obtained. However, this detection method requires the installation of detection rollers, which requires many devices and has high economic costs. In addition, it can only obtain the deformation analysis of the guide rail 1, and cannot directly obtain the stress condition of the guide rail 1. In the prior art, there is also a method of measuring the verticality of the guide rail 1 by setting laser detection devices at the upper and lower ends of the guide rail 1, but this method still requires the elevator to be modified and the laser detection device to be installed. At the same time, it is also impossible to directly obtain the stress condition of the guide rail 1, and the cost is high.

[0086] Working principle:

[0087] The detection method of the present invention first analyzes the deformation coordination relationship between the guide rail 1 and the car 2, and calculates the relationship between the elevator inclination and the load on the elevator guide rail 1. Then, based on a simplified elevator guide rail 1 model, the bending moment of the guide rail 1 is calculated. Using the selected parameters of the elevator guide rail 1 of the corresponding model, the bending stress of the elevator guide rail 1 is calculated, and the relationship between the elevator inclination and the bending stress on the guide rail 1 is derived. During implementation, it is only necessary to install a digital inclinometer 6 on the elevator. The stress on the guide rail 1 can be converted in real time by recording the elevator inclination in real time, ensuring that the guide rail 1 operates within a safe range. There is no need to re-modify the elevator that has been put into use, which is low-cost and effective.

[0088] In the description of the present invention, it should be understood that if the terms "upper," "lower," "left," "right," etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the purpose of facilitating the description of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, the terms describing the positional relationship in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meanings of the above terms can be understood based on the specific circumstances. In addition, if there are descriptions of "first," "second," etc. in the embodiments of the present invention, the descriptions of "first," "second," etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, the definition of "first" or "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or solutions that meet both A and B.

[0089] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention, or direct / indirect applications in other related technical fields should be included in the scope of protection of the claims of the present invention.

Claims

1. A stress tracking detection method for elevator guide rails, characterized in that: The following detection steps are included: S1: Establish a guide rail car model and obtain basic parameters of the guide rail car, including the car's deadweight G and the offset e of the car's center of gravity relative to the suspension center; S2: Calculate the overturning moment of the car based on the basic parameters obtained ,get ; S3: Select two force points on the guide rail, the distance between the two force points is h, and calculate the force at the two force points According to the guide rail force balance relationship, the moment at the force point is equal to the overturning moment of the car , and then according to the moment calculation formula, the overturning moment of the car is obtained with force The calculation relationship between : ； In step S3, the two force points are the positions of the two guide shoes on the guide rail, namely position point A and position point B, wherein the distance between the two brackets of the guide rail is , the distance between position point A and the adjacent guide rail bracket is a; S4: Calculate the deformation displacement at two stress points respectively and According to the approximate differential equation of simply supported beam deflection curve in material mechanics and the superposition principle of bending deformation, we can obtain with force The calculation relationship between , with force The calculation relationship between ; S5: Calculate the overturning angle of the guide rail , get the overturning angle of the guide rail The calculation relationship between the deformation displacement of the two force points : ； S6: Combine steps S1-S5 and calculate the relationship The deformation displacement in and Utilize force Indicates that the overturning angle of the guide rail is obtained The forces at the two points The calculation relationship between ; S7: Calculate the bending moment at two load points and , take the maximum bending moment between two load points , and obtain the maximum bending moment with force The calculation relationship between ; S8: Calculate the bending stress on the guide rail , according to the bending stress calculation formula, the bending stress is obtained with force The calculation relationship between the capsizing angle with force The calculation relationship between the two is brought into the bending stress In the calculation, the bending stress is obtained and overturning angle The calculation relationship between , according to the calculation formula It can be concluded that the overturning angle of the guide rail can be monitored in real time Convert the bending stress on the guide rail , which is convenient for monitoring the deformation degree of the guide rail, thereby ensuring that the guide rail operates within a safe range; The bending stress calculation formula in step S8 is: , where W represents the bending section coefficient; When 2a+h- >0, the maximum bending moment with force The calculation relationship between as follows: ； When 2a+h- <0, the maximum bending moment with force The calculation relationship between as follows: ； Where E is the elastic modulus of the selected guide rail, and I is the moment of inertia of the selected guide rail.

2. The method for detecting stress following of an elevator guide rail according to claim 1, characterized in that: Simplify the guide rail car model and calculate the deformation displacement of point A in step S4 and the deformation displacement of point B , calculation relationship And the calculation relationship The following calculation results are obtained: ， ； Where E is the elastic modulus of the selected guide rail, and I is the moment of inertia of the selected guide rail.

3. The method for detecting stress following of an elevator guide rail according to claim 2, wherein: The calculation relationship in step S6 for: 。 4. The method for detecting stress following of an elevator guide rail according to claim 3, characterized in that In step S7, the steps for calculating the bending moments at the two force points are as follows: S7.1: The positions of the two brackets on the guide rail are position points C and D, respectively, and the force balance relationship is obtained. , taking point C as the center of the rotation axis, according to the moment balance relationship ,get ; S7.2: Calculate the moment between position C and position A separately , torque between position point A and position point B , torque between position point B and position point D , find the position of maximum bending moment on the guide rail.

5. The method for detecting stress following of an elevator guide rail according to claim 4, characterized in that: In step S7.2, the torque calculation results between the positions are as follows: ； ； ； Where x represents the distance from the bending moment calculation point to position point C.

6. The method for detecting stress following of an elevator guide rail according to claim 5, characterized in that: According to the calculation results in step S7.2, the maximum bending moment position on the guide rail is at position A or position B. The maximum bending moment between the two positions is taken. , and obtain the maximum bending moment with force The calculation relationship between as follows: When 2a+h- >0, , When 2a+h- <0, .

7. The method for detecting stress following of an elevator guide rail according to any one of claims 1 to 6, characterized in that: The tilt angle of the guide rail Measured by a digital inclinometer installed on the elevator.

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