An online checking method and system for action speed of an elevator centrifugal overspeed governor based on a physical model

Abstract

The present application belongs to the technical field of elevator safety device, in particular to a method and system for online checking of the action speed of a centrifugal elevator speed governor without overspeed and without disengaging the elevator body. The purpose is to provide an online checking method and system for the action speed of a centrifugal elevator speed governor based on a physical model drive, so as to realize fast and frequent online checking of the speed governor. The technical solution is an online checking method for the action speed of a centrifugal elevator speed governor based on a physical model drive, comprising the following steps: step S1, establishing a flyweight dynamics model; step S2, zero point calibration; step S3, key point acquisition; and step S4, online checking.

Description

Technical Field

[0001] This invention belongs to the field of elevator safety device technology, and in particular relates to a method and system for online verification of the operating speed of a centrifugal elevator speed governor without overspeeding or detaching it from the elevator body. Background Technology

[0002] The speed governor is one of the most important safety components of an elevator, playing a crucial role in promptly detecting abnormal overspeed situations and triggering the safety brakes to stop the car. The accuracy and reliability of the speed governor's operation directly affect elevator safety. Currently, speed governor calibration methods are very inconvenient, requiring personnel to disassemble the speed governor on-site, completely disconnect it from the elevator operating system, and then simulate overspeed conditions using an external drive motor. Speed ​​calibration for machine-room-less elevators is even more complex, often requiring the entire speed governor to be disassembled and taken outside the shaft for calibration due to limited operating space.

[0003] Traditional speed governor verification methods involve using an external drive motor to trigger the speed governor to operate under overspeed conditions. This means that the speed governor cannot reach this condition during normal elevator operation, and the speed governor must be disconnected from the running elevator for verification. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings in the above-mentioned background technology and provide a method and system for online verification of the operating speed of elevator centrifugal speed governor based on a physical model, so as to achieve fast and frequent online verification of the speed governor.

[0005] The technical solution of this invention is: A physical model-driven online verification method for the operating speed of an elevator centrifugal speed governor includes the following steps: Step S1: Establish the dynamic model of the slingshot; Step S2: Zero point calibration; Step S3: Key point acquisition; Step S4: Online verification.

[0006] The dynamic model of the throwing block is as follows: in, D normal This refers to the radial displacement of the sling during elevator operation. k z These are key model parameters. v The speed at which the elevator car travels. v s The critical speed of the elevator car when the rocker arm is displaced.

[0007] The zero-point calibration in step S2 includes: obtaining the zero-point position of the swerve while the speed limiter is stationary. L min With extreme positions L max ,Depend on D action =L max -L min Obtain the speed limiter's operating threshold D action .

[0008] The key point acquisition in step S3 includes: The elevator car's speed is obtained as the critical speed when the sling begins to move radially. v s ; Obtain the average speed of the elevator car during ascent and descent. v And the current position of the throw block. L normal ,Depend on D normal = L normal -L min Obtaining small radial displacement D normal ; Critical speed v s Small radial displacement D normal and running speed v Substituting into the dynamic model of the tossing block, the key model parameters are obtained. k z ; Key model parameters k z The dynamics model of the slingshot is then incorporated and curve fitting is performed.

[0009] The online verification in step S4 includes: According to normal operating speed v Calculate the minimum action speed within the permissible range of action speed. V min With maximum motion speed V max ; Action threshold D action Substituting into the dynamic model of the sway block, the speed limiter's operating speed is obtained. v action ; If the speed limiter operates within the allowable range, the speed limiter is deemed to meet the requirements; otherwise, the speed limiter is deemed to be operating abnormally.

[0010] A physics model-driven online verification system for the operating speed of an elevator centrifugal speed governor, employing the aforementioned physics model-driven online verification method for the operating speed of an elevator centrifugal speed governor, includes: The block displacement detection module is used to detect the radial displacement of the block relative to a fixed reference. The elevator system control module is used to detect the running speed of the elevator car; The data acquisition and processing module is used to acquire and process data from the block displacement detection module and the elevator system control module, and to perform model fitting. The action speed verification module is used to predict the action speed of the speed limiter and complete the qualification judgment; The alarm display module is used to verify data, output verification results, and issue non-compliance alarms.

[0011] The block displacement detection module is fixed on the housing of the centrifugal speed limiter; the block displacement detection module is a laser displacement sensor, an inductive sensor, or a Hall sensor.

[0012] The data acquisition and processing module is electrically connected to the block displacement detection module and the elevator system control module; the motion speed verification module is electrically connected to the data acquisition and processing module and the alarm display module.

[0013] The beneficial effects of this invention are: This invention aims to solve the problem that speed limiter calibration in the prior art requires actual overspeed tests. This invention performs speed verification based on a rockfall dynamics model. It only requires adding a sensor to the speed governor to collect data, without disassembling the speed governor from the elevator or adding an external drive motor. Online verification can be performed while the elevator is running normally. It has the advantages of high safety, high efficiency, and non-invasiveness, which improves the accuracy and reliability of the verification results and saves verification time and cost. Attached Figure Description

[0014] The following describes some specific embodiments of the invention in a detailed manner by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or portions.

[0015] Figure 1 This is a flowchart of the present invention.

[0016] Figure 2 This is a structural diagram of a centrifugal speed limiter.

[0017] Figure 3 This is a schematic diagram of the fitting curve of an embodiment.

[0018] Figure label: Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0020] like Figure 2 As shown, the centrifugal speed limiter includes a throwing block 1, a connecting rod 2, a spring 3, and a speed limiter wheel 4. When the speed limiter wheel starts to rotate, as the speed of the speed limiter wheel increases, the centrifugal force on the throwing block continues to increase, driving the throwing block to move radially outward, thereby continuously compressing the spring.

[0021] Existing speed governor calibration methods mostly rely on the "drive motor acceleration method" (i.e., the speed governor must be accelerated regardless). However, in a normally operating elevator, the speed governor also operates synchronously with changes in speed, just before reaching its limit. Therefore, this invention monitors the speed governor's operating state during normal elevator operation, and combines the relationship between displacement, speed, and limit values ​​to determine the range of the speed governor's operating speed, thus completing online elevator speed governor calibration. This invention performs online elevator speed governor calibration based on extrapolation prediction using small sample data, meaning it doesn't require the speed governor to reach its operating speed. This is particularly advantageous for machine-room-less elevators or high-speed elevators, where traditional contact-based measurements are difficult to implement and pose safety hazards. The non-invasive measurement method of this invention offers significant advantages.

[0022] Example 1 like Figure 1 As shown, an online verification method for the operating speed of an elevator centrifugal speed governor based on a physics model includes the following steps: Step S1: Establish the dynamic model of the slingshot. Based on the structure of the centrifugal speed limiter, and according to the balance between the force characteristics of the thrown block and the spring return force, a dynamic model is established between the radial displacement of the thrown block and the speed limiter wheel rotation speed.

[0023] The dynamic model of the slingshot is as follows: in, D normal This refers to the radial displacement of the sling during elevator operation. k z These are key model parameters. v The speed of the elevator car (the linear speed of the speed limiter). v s The critical speed of the elevator car when the rocker arm is displaced.

[0024] Step S2, Zero point calibration When the elevator stops running, the speed governor remains stationary, and the zero-point position of the sway block is obtained. L min With extreme positions L max ,Depend on D action =L max -L min Obtain the speed limiter's operating threshold D action .

[0025] A tool can be used to move the swing block to its limit position. When the swing block is at its limit position (the displacement distance of the swing block reaches the action threshold), D action The speed limiter will trigger a speed limiting action.

[0026] Zero-point calibration is performed using the block displacement detection module to obtain the zero-point position of the block. L min With extreme positions L max The zero-point position is acquired by the data acquisition and processing module and measured by the displacement detection module. L min With extreme positions L max And calculate the action threshold D action .

[0027] Step S3: Key Point Collection 1) Acquisition of critical velocity When the elevator is started, the traction machine drives the traction sheave to rotate. The traction sheave, through the traction steel wire rope, moves the elevator car up and down, accelerating the elevator car from a standstill until it reaches the rated lifting speed. V normal Because the elevator car is also connected to the speed governor wheel of the speed governor via a speed-limiting steel wire rope, the speed governor wheel also accelerates from a stationary state along with the elevator car until it reaches the rated speed that matches the rated lifting speed of the elevator car (the speed of the elevator car is the linear speed of the speed governor wheel). The running speed of the elevator car... Speed ​​of the speed limiter wheel The relationship is .

[0028] During the acceleration of the elevator car, the speed limiter wheel rotates continuously, and the centrifugal force on the swing block gradually increases. When the centrifugal force exceeds the preload of the spring, the swing block begins to undergo radial displacement. The speed of the elevator car at this moment is taken as the critical speed. vs .

[0029] The elevator control module determines whether the elevator block has radial displacement by detecting the displacement of the ejector block, and obtains the critical speed of the elevator car through the elevator system control module. v s The critical speed measured by the elevator system control module is acquired through the data acquisition and processing module. v s . 2) Collect minute radial displacement and normal operating speed When the elevator car is moving at a constant speed, the system controls the elevator car to operate within the rated safe speed range (below the speed limiter's operating speed) and obtains the elevator car's current operating speed. v Since the speed limiter wheel also rotates at a constant speed, the slinger produces a small radial displacement under the action of centrifugal force, thus obtaining the current position of the slinger. L normal ,Depend on D normal =L normal -L min Obtaining small radial displacement D normal ( 0≤D normal ≤D action ).

[0030] The elevator car's speed is collected through the elevator system control module. v The current position of the thrown block is obtained through the block displacement detection module. L normal The data acquisition and processing module collects the operating speed measured by the elevator system control module. v And the current position measured by the block displacement detection module. L normal And calculate the minute radial displacement D normal .

[0031] 3) Data processing The data acquisition and processing module filters the acquired data to remove the effects of mechanical vibration and electromagnetic interference, and selects the critical speed at the initial displacement of the elevator. v s A small radial displacement was selected during the elevator's stable operation phase (5 seconds after entering the uniform speed phase). D normal and running speed v As valid data.

[0032] 4) Fitting the dynamic model of the slingshot From the dynamic model of the slingshot, we can see that Critical speed v s Small radial displacement D normal and running speed v Substituting into the dynamic model of the tossing block, the key model parameters are obtained. k z .

[0033] Key model parameters k z By substituting the data into the dynamic model of the slingshot and performing curve fitting, the small radial displacement can be obtained. D normal Regarding running speed v The curve showing the change.

[0034] Curve fitting of the sling-throw dynamics model is performed using the data acquisition and processing module.

[0035] Step S4: Online Verification The speed limiter activation module predicts the speed limiter activation speed and calculates the allowable range of the speed limiter's activation speed (obtained directly from the rated speed and national standard). The two are compared. When the predicted speed limiter activation speed falls within the allowable range, the speed limiter activation speed is deemed to meet the requirements. When the predicted activation speed exceeds the allowable range, the speed limiter activation speed is deemed abnormal, and the verification result and deviation information are output.

[0036] 1) Calculate the allowable range of motion speed According to normal operating speed v Calculate the minimum action speed within the permissible range of action speed. V min With maximum motion speed V max .

[0037] According to GB / T 7588-2020.1 "Safety Code for Elevator Manufacturing and Installation Part 1: Passenger Elevators and Freight Elevators" section 5.6.2.2.1.1, the speed governor's operating speed should be at least equal to 115% of the rated speed, and not greater than "1.25v + 0.25 / v for progressive safety gears with a rated speed greater than 1.00 m / s (where v is the rated speed)".

[0038] v min = v ×1.15 v max =1.25× v +0.25 / v 2) Predict the speed limiter's activation speed From the dynamic model of the slingshot, we can see that

[0039] Action threshold D action Substituting into the dynamic model of the sway block, the speed limiter's operating speed is obtained. v action .

[0040] 3) Verify the speed limiter If the speed limiter operates at a speed within the permissible range... v min ≤ v action ≤ v max The speed limiter's operating speed is determined to meet the requirements. If the speed limiter operates at a speed greater than its maximum operating speed. v max < v action This indicates that when the elevator speed has reached the speed limiter's operating speed, the swing block still has not produced the expected observable displacement, the spring clamping force is too large, and the speed limiter has failed to perform its normal function.

[0041] If the speed limiter operates at a speed less than the minimum operating speed... v action < v min This indicates that the elevator's speed did not reach the speed limiter's activation speed before the expected observable displacement was generated. The spring clamping force was too small, which caused the speed limiter to be triggered frequently, affecting the normal operation of the elevator.

[0042] Based on the structure of the speed limiter, the dynamic model of the swerving block is derived. The specific process is as follows: 1) The centrifugal force on the throwing block component satisfies the equation In the formula, F 1 For centrifugal force, m The total mass of the block-throwing mechanism and the linkage mechanism is... Angular velocity of rotation ( rad / s ), r Let be the radius of motion.

[0043] 2) Ignoring the influence of gravity (gravity always exists and its magnitude remains constant), when the spring is within its working range, the spring overcomes the centrifugal force, and its compression distance satisfies the equation... In the formula, n The effective number of coils of the spring. D The mean diameter of the spring.G Let be the spring shear modulus. l p Let be the polar moment of inertia of the circular cross section. For a given spring, all of the above parameters are constants.

[0044] 3) Simplify the above formula to That is, it satisfies Hooke's Law. In the formula, F 2 The compressive force on a spring refers to the actual rebound force generated by the elastic deformation of a spring when it is subjected to an external force (such as centrifugal force), which is used to resist compression and balance the external force.

[0045] 4) When the speed limiter wheel drives the swing block to rotate, the swing block is subjected to force that compresses the spring, causing deformation. F 1 and F 2 Satisfy a linear relationship , k 2 is the transmission coefficient.

[0046] 5) Spring compression deformation f With rotational speed v The square relation satisfies The square of the speed limiter's rotational speed is linearly related to the spring compression deformation.

[0047] 6) The total mass of the block-throwing mechanism and the linkage mechanism in the above formula m Radius of movement r For the same speed limiter, the coefficient is a fixed factor, and k 1 , k 2 merged together k c The relationship satisfies the spring compression deformation. .

[0048] 7) Distance the thrown block moves D normal With spring compression distance f exist , k d As a constant, we get 。

[0049] 8) k d 、k c Combined into constants kz ,Right now .

[0050] 9) Considering the initial preload of the spring in actual working conditionsF 0 Spring preload refers to the initial internal compressive or tensile force generated by a spring due to its structural characteristics when no external force is applied. The above model applies to the stage after centrifugal force overcomes the preload. A modified model yields: when the velocity... v When the speed is less than the critical speed (preload dead zone), the radial displacement of the throwing block is 0; when the speed is less than the critical speed (preload dead zone), the radial displacement of the throwing block is 0. v When the speed is greater than the critical speed .

[0051] In summary, the dynamic model of the slingshot is based on the balance between the centrifugal force and the return spring force acting on the slingshot. Key model parameters... kz This is a comprehensive response coefficient that reflects the critical threshold for starting the spring preload and the rate of change of displacement with rotational speed.

[0052] Example 2 like Figure 3 As shown, the online verification of a certain elevator includes: 1) Zero-point calibration: Action threshold D action =5.5mm; 2) Preload dead zone: Figure 3 The curve in the 0~0.4m / s range fits the horizontal axis (displacement is 0), indicating that the centrifugal force has not yet overcome the spring preload in this speed range, and the swing block is in a stationary state. When the speed limiter speed exceeds 0.4m / s, the swing block begins to move. 3) Key point collection: The elevator is at its rated speed V normal When running at 1.75 m / s, the measured displacement of the thrown block was 3.0 mm. Figure 3 (Using square markers) to perform online correction of model parameters; 4) Prediction and Judgment: Based on rated speed V normal Calculations based on 1.75 m / s yield an allowable range of motion speeds of approximately 2.01-2.33 m / s. Figure 3 (Middle shaded area); substitute the action threshold of the speed limiter's mechanical trigger. D action =5.5mm, the model calculates the predicted action speed Vaction≈2.23m / s (triangle mark in the figure). This predicted value falls accurately within the allowable action speed range, and the speed limiter is deemed to have passed the verification.

[0053] Example 3 This embodiment provides an online verification system for the action speed of an elevator centrifugal speed governor based on a physical model. The system employs the aforementioned online verification method for the action speed of an elevator centrifugal speed governor based on a physical model and includes: a centrifugal speed governor, an elevator system control module, a block displacement detection module, a data acquisition and processing module, an action speed verification module, and an alarm display module.

[0054] The block displacement detection module is used to detect the radial displacement of the block relative to a fixed reference.

[0055] The elevator system control module is used to detect the operating speed of the elevator car.

[0056] The data acquisition and processing module is used to acquire and process data from the block displacement detection module and the elevator system control module, and to perform model fitting.

[0057] The action speed verification module is used to predict the action speed of the speed limiter and complete the qualification judgment.

[0058] The alarm display module is used to verify data, output verification results, and issue non-compliance alarms.

[0059] The block displacement detection module is fixed to the housing of the centrifugal speed governor. The block displacement detection module can be a laser displacement sensor, an inductive sensor, or a Hall effect sensor. The elevator system control module is a built-in module of the elevator system. The data acquisition and processing module is electrically connected to the block displacement detection module and the elevator system control module. The motion speed verification module is electrically connected to the data acquisition and processing module and the alarm display module.

[0060] Through the above methods and systems, this invention achieves online prediction and verification of the speed limiter's operating speed without actually triggering the speed limiter or engaging in overspeeding, thereby reducing verification risks and improving verification efficiency and repeatability.

[0061] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A method for online verification of the operating speed of a centrifugal speed governor in an elevator based on a physics model, comprising the following steps: Step S1: Establish the dynamic model of the slingshot; Step S2: Zero point calibration; Step S3: Key point acquisition; Step S4: Online verification.

2. The online verification method for the action speed of an elevator centrifugal speed governor based on a physics model as described in claim 1, characterized in that: The dynamic model of the throwing block is as follows: Among them, D normal k is the radial displacement of the sway block during elevator operation. z Here are the key model parameters, where v is the speed of the elevator car. s The critical speed of the elevator car when the rocker arm is displaced.

3. The online verification method for the action speed of an elevator centrifugal speed governor based on a physics model as described in claim 2, characterized in that: The zero-point calibration in step S2 includes: obtaining the zero-point position L of the sling block while the speed limiter is stationary. min With extreme position L max , by D action =L max -L min Obtain the speed limiter's operating threshold D action .

4. The online verification method for the action speed of an elevator centrifugal speed governor based on a physics model as described in claim 3, characterized in that: The key point acquisition in step S3 includes: The elevator car's running speed v is obtained as the critical speed when the slinger begins to undergo radial displacement. s ; Obtain the elevator car's average speed of ascent and descent (v) and the current position (L) of the sway block. normal , by D normal =L normal -L min A small radial displacement D is obtained normal ; The critical velocity v s Small radial displacement D normal Substituting the running speed v into the rock-throwing dynamics model, we obtain the key model parameter k. z ; Key model parameter k z The dynamics model of the slingshot is then incorporated and curve fitting is performed.

5. The online verification method for the action speed of an elevator centrifugal speed governor based on a physics model as described in claim 4, characterized in that: The online verification in step S4 includes: The minimum operating speed V is calculated based on the normal operating speed v, within the permissible range of operating speed. min With maximum motion speed V max ; Action threshold D action Substituting into the dynamic model of the sway block, we obtain the speed limiter's operating speed v. action ; If the speed limiter operates within the allowable range, the speed limiter is deemed to meet the requirements; otherwise, the speed limiter is deemed to be operating abnormally.

6. A physical model-driven online verification system for the operating speed of an elevator centrifugal speed governor, employing the physical model-driven online verification method for the operating speed of an elevator centrifugal speed governor as described in any one of claims 1-5, comprising: The block displacement detection module is used to detect the radial displacement of the block relative to a fixed reference. The elevator system control module is used to detect the running speed of the elevator car; The data acquisition and processing module is used to acquire and process data from the block displacement detection module and the elevator system control module, and to perform model fitting. The action speed verification module is used to predict the action speed of the speed limiter and complete the qualification judgment; The alarm display module is used to verify data, output verification results, and issue non-compliance alarms.

7. The online verification system for the action speed of an elevator centrifugal speed governor based on a physical model as described in claim 6, characterized in that: The block displacement detection module is fixed on the housing of the centrifugal speed limiter; the block displacement detection module is a laser displacement sensor, an inductive sensor, or a Hall sensor.

8. The online verification system for the operating speed of an elevator centrifugal speed governor based on a physical model as described in claim 7, characterized in that: The data acquisition and processing module is electrically connected to the block displacement detection module and the elevator system control module; the motion speed verification module is electrically connected to the data acquisition and processing module and the alarm display module.

Images