Disc brake empty time online detection method

Abstract

The present application belongs to the technical field of mine hoist brake system detection, and specifically discloses a disc brake idle time online detection method, which collects the displacement value of the brake piston and the emergency stop switch state signal in real time, starts timing immediately when detecting the emergency stop switch action signal, calculates the change amount of the brake piston displacement in each sampling period by using the brake piston displacement value, analyzes the change trend of the change amount, finds the maximum value of the brake piston displacement change amount, and further determines the ending moment of the idle time, so that the online real-time detection can be performed during the normal operation of the hoist or during the periodic test, without stopping, thereby improving the detection efficiency and production continuity.

Description

Technical Field

[0001] This invention belongs to the field of detection technology for mine hoisting braking systems, and specifically discloses an online detection method for the idle time of a disc brake. Background Technology

[0002] As a key piece of equipment for safe coal mine production, the reliability of the braking system of a mine hoist directly affects mine production and personnel safety. The "Coal Mine Safety Regulations" clearly require that the disc brakes of mine hoists undergo regular no-load time testing to ensure the braking system can respond promptly in emergencies. No-load time refers to the time interval from the issuance of the braking signal to the actual generation of braking torque by the brake; this parameter is an important indicator for evaluating the performance of the braking system.

[0003] Currently, the detection of the idle time of disc brakes mainly uses offline testing methods, which require the machine to be stopped before manual testing can be performed, and has the following shortcomings: Low testing efficiency disrupts normal production. It cannot reflect the actual working status of the braking system in real time; Manual operation is subject to subjective errors, resulting in poor consistency of test results. It is impossible to continuously monitor and provide early warnings of the braking system status.

[0004] With the development of smart mine construction, higher requirements have been placed on the online monitoring and intelligent diagnosis of hoist braking systems. Therefore, developing a method that can detect the idle time of disc brakes online, in real time, and accurately is of great significance for ensuring the safe operation of mine hoists and realizing preventive maintenance. Summary of the Invention

[0005] To address the problems in the background art, this invention discloses an online detection method for the idle time of a disc brake, which can detect the idle time of the brake in real time without affecting the normal operation of the hoist, providing reliable data support for the status monitoring and fault early warning of the braking system.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: A method for online detection of the idle time of a disc brake, specifically including the following steps: S1. Detection System Construction and Signal Acquisition: A displacement sensor is installed at the rear end cover of the disc brake to detect the displacement of the brake piston in real time; at the same time, an emergency stop signal is obtained from the emergency stop switch of the hoist's electronic control system; an embedded controller is used as the core of data acquisition and processing to collect the displacement value of the brake piston and the status signal of the emergency stop switch in real time. S2. Execution of the idle time detection algorithm: When the embedded controller detects the emergency stop switch action signal, it immediately starts the timer and collects the displacement value L(t) of the brake piston in real time at a sampling interval of 10 milliseconds, where t is the sampling time point; S3. Calculation of piston displacement change: Calculate the change in brake piston displacement within each sampling period, ΔL(t) = |L(t) - L(t-10ms)|, where ΔL(t) represents the change in brake piston displacement at time t relative to the previous sampling moment, L(t) is the brake piston displacement value at the current sampling moment, and L(t-10ms) is the brake piston displacement value at the previous sampling moment; S4. Change characteristic analysis: Continuously record and analyze the changing trend of ΔL(t). ΔL(t) shows a trend of first increasing and then decreasing. S5. Determining the maximum change: Find the maximum value △L_max, which corresponds to the moment when the piston moves the fastest, which is close to the critical point when the brake shoe contacts the brake disc. S6. Determination of the end point of the idle time: ΔL(t) gradually decreases. When the value of ΔL(t) corresponding to a certain sampling moment is first detected to be less than half of ΔL_max, this moment is determined to be the end point of the idle time t_end. S7. Calculation of idle time: The time elapsed from the start of the emergency stop switch action signal to the end point of the idle time determined in step S6 is the idle time T of the brake, T = t_end - t_start, where t_start is the moment the emergency stop switch is activated.

[0007] Furthermore, in the online detection method for the idle time of the disc brake, in step S4, at the initial stage of braking, the brake piston begins to move but the brake shoe has not yet contacted the brake disc, and ΔL(t) gradually increases; as the brake piston continues to move, when the brake shoe contacts the brake disc and begins to generate braking force, the speed of the brake piston slows down, and ΔL(t) begins to decrease.

[0008] Furthermore, in the online detection method for the idle time of the disc brake, in step S1, the displacement sensor used is a ZJ10-1 displacement sensor.

[0009] Compared with the prior art, the beneficial effects of the present invention are: This invention provides an online detection method for the idle time of a disc brake. It collects the displacement value of the brake piston and the status signal of the emergency stop switch in real time. When the emergency stop switch is activated, timing begins immediately. The change in brake piston displacement ΔL(t) within each sampling period is calculated using the brake piston displacement value. The trend of ΔL(t) is analyzed, showing an initial increase followed by a decrease. The maximum value of the brake piston displacement change ΔL_max is identified, thus determining the end time of the idle time. This method allows for online real-time detection during normal operation of the hoist or during periodic testing, without requiring machine shutdown, thus improving detection efficiency and production continuity. The present invention provides an online detection method for the idling time of a disc brake. It employs a high-precision displacement sensor and a high-speed data acquisition system, combined with an intelligent algorithm, to accurately identify the end point of the idling time. This method achieves high detection accuracy and avoids subjective errors associated with manual detection. The present invention provides an online detection method for the idle time of disc brakes. The entire detection process is completed automatically without manual intervention, and the detection results are automatically stored and analyzed, demonstrating a high degree of automation. Attached Figure Description

[0010] Figure 1 This is a flowchart of the online detection method for the idle time of a disc brake according to the present invention; Figure 2 This is a schematic diagram of the brake piston displacement curve in an embodiment of the present invention. Detailed Implementation

[0011] To better understand the present invention, the following embodiments further illustrate the content of the invention, but the scope of protection of the present invention is not limited to the embodiments described below. Numerous specific details are set forth in the following description to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details.

[0012] Combined with appendix Figure 1-2 The present invention provides a detailed description of the online detection method for the idle time of a disc brake: S1. Detection System Construction and Signal Acquisition: A displacement sensor is installed at the rear end cover of the disc brake to detect the displacement of the brake piston in real time. The displacement sensor adopts the ZJ10-1 displacement sensor with a range of 10mm. The product adopts an integrated stainless steel cylindrical structure, which is easy to install and has the advantages of good shock resistance and impact resistance, high accuracy, good linearity and stability. The embedded controller collects the displacement information of the brake piston online and obtains the emergency stop signal from the emergency stop switch of the hoist electrical control system. S2. Execution of the idle time detection algorithm: When the embedded controller detects the emergency stop switch action signal, it immediately starts the timer and records t_start=50ms. It should be noted that the sampling interval can be selected as needed, ranging from 5 to 20 milliseconds. To ensure accuracy and sensitivity while facilitating sampling, this invention preferably uses a 10-millisecond sampling interval to collect the displacement value L(t) of the brake piston in real time. A schematic diagram of the brake piston displacement curve is plotted with time and displacement values ​​on the horizontal and vertical axes, as shown below. Figure 2 As shown; S3. Calculation of piston displacement change: The embedded controller uses an intelligent algorithm to calculate the change in brake piston displacement in each sampling period, ΔL(t) = |L(t) - L(t-10ms)|, where ΔL(t) represents the change in brake piston displacement at time t relative to the previous sampling moment, L(t) is the brake piston displacement value at the current sampling moment, and L(t-10ms) is the brake piston displacement value at the previous sampling moment; S4. Analysis of the characteristics of change: Continuously record and analyze the trend of change of ΔL(t). ΔL(t) shows a trend of first increasing and then decreasing. In the initial stage of braking, the brake piston begins to move but the brake shoe has not yet contacted the brake disc, and ΔL(t) gradually increases. As the brake piston continues to move, when the brake shoe contacts the brake disc and begins to generate braking force, the speed of the brake piston slows down, and ΔL(t) begins to decrease. S5. Determining the maximum change: Find the maximum value △L_max, △L_max=(0.88-0.74)mm, which corresponds to the time t=300ms. t=300ms corresponds to the moment when the piston moves the fastest, which is usually close to the critical point when the brake shoe contacts the brake disc. S6. Determination of the end point of the idle time: Continue detection, ΔL(t) gradually decreases. When the value of ΔL(t) corresponding to a certain sampling time is detected to be less than half of ΔL_max for the first time, this time is determined to be the end of the idle time t_end, t_end=340ms; S7. Calculation of no-load time: The time elapsed from the start of the emergency stop switch action signal to the end of the determined no-load time is the no-load time T of the brake. T = t_end - t_start = 290ms, that is, the no-load time of the disc brake is 290 milliseconds.

[0013] The entire testing process is completed automatically. Online real-time testing is performed during normal operation of the hoist or during periodic testing without stopping the machine, which improves testing efficiency and production continuity. Moreover, it requires no manual intervention, has high testing accuracy, and automatically stores and analyzes the test results, resulting in a high degree of automation.

[0014] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solutions of the present invention, as long as they do not depart from the spirit and scope of the technical solutions of the present invention, should be covered within the scope of the claims of the present invention.

Claims

1. A method for online detection of the idle time of a disc brake, characterized in that, Specifically, the following steps are included: S1. Detection System Construction and Signal Acquisition: A displacement sensor is installed at the rear end cover of the disc brake to detect the displacement of the brake piston in real time; at the same time, an emergency stop signal is obtained from the emergency stop switch of the hoist's electronic control system. An embedded controller is used as the core for data acquisition and processing to collect the displacement value of the brake piston and the status signal of the emergency stop switch in real time. S2. Execution of the idle time detection algorithm: When the embedded controller detects the emergency stop switch action signal, it immediately starts the timer and collects the displacement value L(t) of the brake piston in real time at a sampling interval of 10 milliseconds, where t is the sampling time point; S3. Calculation of piston displacement change: Calculate the change in brake piston displacement within each sampling period, ΔL(t) = |L(t) - L(t-10ms)|, where ΔL(t) represents the change in brake piston displacement at time t relative to the previous sampling moment, L(t) is the brake piston displacement value at the current sampling moment, and L(t-10ms) is the brake piston displacement value at the previous sampling moment; S4. Analysis of the characteristics of change: The change process of ΔL(t) is continuously recorded and analyzed. ΔL(t) shows a trend of first increasing and then decreasing. S5. Determining the maximum change: Find the maximum value △L_max, which corresponds to the moment when the piston moves the fastest, usually close to the critical point when the brake shoe contacts the brake disc. S6. Determination of the end point of the idle time: ΔL(t) gradually decreases. When the value of ΔL(t) corresponding to a certain sampling moment is first detected to be less than half of ΔL_max, this moment is determined to be the end point of the idle time t_end. S7. Calculation of idle time: The time elapsed from the start of the emergency stop switch action signal to the end point of the idle time determined in step S6 is the idle time T of the brake, T = t_end - t_start, where t_start is the moment the emergency stop switch is activated.

2. The online detection method for the idle time of a disc brake according to claim 1, characterized in that, In step S4, at the initial stage of braking, the brake piston begins to move but the brake shoes have not yet contacted the brake disc, and ΔL(t) gradually increases; the brake piston continues to move, and when the brake shoes contact the brake disc and begin to generate braking force, the speed of the brake piston slows down, and ΔL(t) begins to decrease.

3. The online detection method for the idle time of a disc brake according to claim 1, characterized in that, In step S1, the displacement sensor used is the ZJ10-1 displacement sensor.

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