A control method and system for impact resistance of a shovel push mechanism

Abstract

This invention discloses a method and system for controlling the impact resistance of an electric shovel's pushing mechanism, comprising: real-time detection of the speed change rate dv / dt of the electric shovel's pushing motor; comparison of the real-time detected speed change rate with a preset value; and adjustment of the pushing force of the electric shovel's pushing mechanism based on the comparison result and the magnitude of the speed change rate. During the operation of the electric shovel, real-time detection of the speed change rate dv / dt of the electric shovel's pushing motor, comparison of the real-time detected speed change rate with a preset value, and adjustment of the pushing force of the electric shovel's pushing mechanism based on the magnitude of the speed change rate achieves impact resistance control of the electric shovel's pushing mechanism. This allows the electric shovel to respond to different pushing torques under different working conditions, and the pushing speed varies with different pushing torques, thereby ensuring digging efficiency during excavation work, making the operation of the electric shovel more user-friendly, and reducing vibration and energy consumption.

Description

Technical Field

[0001] This invention relates to the field of mining machinery, specifically to a control method and system for the impact resistance of an electric shovel pushing mechanism. Background Technology

[0002] An electric shovel, also known as a front shovel excavator, is primarily used for ore extraction and rock stripping in open-pit mines. Its lifting and pushing mechanisms work together to excavate materials. Standard bucket capacities for electric shovels start from 4m³. 3 ~75m 3 They operate in extremely harsh environments such as extreme cold, high temperature, high altitude, and high dust, and their working loads are extremely complex, including heavy loads, strong impacts, and random changes. The equipment vibrates greatly during operation.

[0003] In the existing technology, when the electric shovel digs materials, the speed of the pushing mechanism often drops rapidly when the bucket encounters large materials, especially when the blasting of mining materials is incomplete or when the bucket is gnawing at the bottom. The torque of the pushing mechanism increases rapidly, causing severe vibration of the equipment, making the electric shovel difficult to operate. At the same time, it can easily cause fatigue to the driver, which not only places high demands on the driver, but is also not friendly to the driver's health. Summary of the Invention

[0004] To address some or all of the technical problems existing in the prior art, the present invention provides a control method and system for the impact resistance of an electric shovel's pushing mechanism, which can solve the vibration problem of the electric shovel during digging, while also improving the full bucket rate of the electric shovel and reducing the fatigue intensity of the driver.

[0005] The technical solution of the present invention is as follows:

[0006] In a first aspect, the present invention provides a method for controlling the impact resistance of an electric shovel pushing mechanism, comprising:

[0007] Real-time detection of the speed change rate dv / dt of the electric shovel's pushing motor;

[0008] Compare the real-time detected rate of change of speed with a preset value;

[0009] Adjust the pushing force of the electric shovel's pushing mechanism based on the comparison results and the magnitude of the speed change rate.

[0010] Furthermore, when adjusting the pushing force of the electric shovel's pushing mechanism based on the comparison results and the rate of change of the pushing motor:

[0011] If dv / dt is greater than or equal to the preset value, the forward torque of the electric shovel pushing mechanism is reduced.

[0012] If dv / dt is less than the preset value, the forward torque of the electric shovel pushing mechanism will be increased or maintained.

[0013] Furthermore, the preset value is between 0 and 5.

[0014] Furthermore, if dv / dt is greater than the preset value, the pushing force of the electric shovel pushing mechanism is: (1-K / 5) 2 ×T 推最大 , among which, T 推最大 This indicates the maximum torque limit of the pushing mechanism, and K represents the torque adjustment coefficient.

[0015] Furthermore, if dv / dt is less than the preset value, and if the speed setting value V of the lifting mechanism is also met at the same time... 提给 The actual value of the lifting mechanism speed V 提实 The difference is less than or equal to the first speed preset value and the push mechanism speed setting value V. 推给 The actual value of the pushing mechanism speed V 推实 If the difference is less than or equal to the preset value of the second speed, then the pushing force of the electric shovel pushing mechanism is: 1.2 × T 推最大 , among which, T 推最大 This indicates the maximum torque limit of the pushing mechanism.

[0016] Furthermore, if dv / dt is less than the preset value, if the speed setting value V of the lifting mechanism is increased... 提给 The actual value of the lifting mechanism speed V 提实 The difference is greater than the first speed preset value and the push mechanism speed setting value V. 推给 The actual value of the pushing mechanism speed V 推实 If the difference is greater than any of the preset values ​​for the second speed, then the pushing force of the electric shovel pushing mechanism is: T 推最大 T 推最大 This indicates the maximum torque limit of the pushing mechanism.

[0017] Furthermore, the first speed preset value is 5% to 20% of the rated speed of the lifting mechanism and the second speed preset value is 5% to 20% of the rated speed of the pressing mechanism.

[0018] Furthermore, the rate of change of velocity dv / dt ranges from 0 to 5.

[0019] Furthermore, the torque adjustment coefficient K is calculated as follows: K = 1 / (dv / dt), where dv / dt is the speed change rate of the electric shovel's push motor.

[0020] Secondly, the present invention also provides an impact-resistant control system for an electric shovel pushing mechanism, comprising:

[0021] The detection module is used to detect the rate of change of speed dv / dt of the electric shovel's pushing motor in real time;

[0022] The comparison module is used to compare the real-time detected rate of change of speed with a preset value;

[0023] The adjustment module is used to adjust the pushing force of the electric shovel pushing mechanism based on the comparison results and the magnitude of the speed change rate.

[0024] The main advantages of the technical solution of this invention are as follows:

[0025] The impact-resistant control method of the electric shovel pushing mechanism of the present invention only requires real-time detection of the speed change rate dv / dt of the electric shovel pushing motor during the operation of the electric shovel; comparing the real-time detected speed change rate with a preset value; and adjusting the pushing force of the electric shovel pushing mechanism according to the detected speed change rate to achieve impact-resistant control of the electric shovel pushing mechanism. This allows the electric shovel to correspond to different pushing torques under different working conditions, and the pushing speed is different when using different pushing torques, thereby ensuring digging efficiency during the digging process, making the operation of the electric shovel more user-friendly, and reducing vibration and energy consumption. Attached Figure Description

[0026] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and constitute a part of this invention, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0027] Figure 1 This is a flowchart illustrating the impact-resistant control method for an electric shovel pushing mechanism according to the present invention.

[0028] Figure 2 A schematic diagram illustrating an embodiment of the present invention showing an electric shovel employing a control method for impact resistance using a pushing mechanism during digging.

[0029] Figure 3 This is a flowchart illustrating a control method for resisting impact using a pushing mechanism in an electric shovel, as provided in an embodiment of the present invention.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1. Electric shovel; 2. Bucket; 3. Pushing mechanism. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0033] The technical solutions provided by the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0034] As attached Figure 1-3 As shown, this embodiment of the invention provides a method for controlling the impact resistance of an electric shovel pushing mechanism, the method comprising:

[0035] Real-time detection of the speed change rate dv / dt of the electric shovel's pushing motor;

[0036] Compare the real-time detected rate of change of speed with a preset value;

[0037] Adjust the pushing force of the electric shovel's pushing mechanism based on the comparison results and the magnitude of the speed change rate.

[0038] Specifically, when adjusting the pushing force of the electric shovel's pushing mechanism based on the comparison results and the magnitude of the speed change rate: if dv / dt is greater than or equal to the preset value, the forward torque of the electric shovel's pushing mechanism is reduced; if dv / dt is less than the preset value, the forward torque of the electric shovel's pushing mechanism is increased or maintained.

[0039] It should be noted that the electric shovel uses a PLC (Programmable Logic Controller) for calculation and logic control, while the motor of the actuator is precisely controlled by a frequency converter. The frequency converter collects the motor's operating data in real time and exchanges data with the PLC via a fieldbus. The frequency converter obtains the motor's speed change rate, set speed, and actual speed, and then transmits them to the PLC for calculation and logical judgment via communication, before sending control commands to the frequency converter for execution.

[0040] In some optional implementations of this embodiment, the preset value is 0-5. This setting ensures that when the electric shovel's pushing mechanism encounters significant resistance during material digging, the output torque increases gradually and evenly while reducing the digging speed. This not only ensures efficient digging but also reduces vibration during the digging process, making it more driver-friendly. It also reduces the number of times the shovel's boom needs to be raised, thus improving overall digging efficiency. It should be noted that, to ensure digging efficiency and to make the electric shovel operation more driver-friendly, reducing vibration and energy consumption, a preset value of 2 is preferred based on practical operation.

[0041] Specifically, the real-time detected rate of change of speed is compared with a preset value. If dv / dt is greater than 2, the pushing force of the electric shovel pushing mechanism is: (1-K / 5). 2 ×T 推最大 , among which, T 推最大 This indicates the maximum torque limit of the pushing mechanism, and K represents the torque adjustment coefficient. The torque adjustment coefficient K is calculated as follows: K = 1 / (dv / dt), where dv / dt is the speed change rate of the electric shovel's pushing motor.

[0042] Specifically, the real-time detected rate of change of speed is compared with a preset value. If dv / dt is less than 2, and the set speed value V of the lifting mechanism is also met, then... 提给 The actual value of the lifting mechanism speed V 提实 The difference is less than or equal to the first speed preset value and the push mechanism speed setting value V. 推给 The actual value of the pushing mechanism speed V 推实 If the difference is less than or equal to the preset value of the second speed, then the pushing force of the excavator's pushing mechanism is: 1.2 × T 推最大 , among which, T 推最大 This indicates the maximum torque limit of the pushing mechanism.

[0043] Specifically, the real-time detected rate of change of speed is compared with a preset value. If dv / dt is less than 2, and the set speed V of the lifting mechanism is met... 提给 The actual value of the lifting mechanism speed V 提实 The difference is greater than the first speed preset value and the push mechanism speed setting value V. 推给 The actual value of the pushing mechanism speed V 推实 If the difference is greater than any of the preset values ​​for the second speed, then the pushing force of the excavator's pushing mechanism is: T 推最大 T 推最大 This indicates the maximum torque limit of the pushing mechanism.

[0044] It should be noted that the preset value in the process of comparing the real-time detected rate of change with the preset value is any value within the preset range, and the above-mentioned preferred values ​​are only illustrative examples.

[0045] In some optional implementations of this embodiment, the first speed preset value is 5% of the rated speed of the lifting mechanism and the second speed preset value is 5% of the rated speed of the pushing mechanism.

[0046] In some optional implementations of this embodiment, the rate of change of velocity dv / dt ranges from 0 to 5.

[0047] More specifically, using the above method, taking the electric shovel 1 as an example, the specific principle of the present invention is explained as follows:

[0048] Specifically, such as Figure 2 and Figure 3 As shown, when the bucket 2 of the electric shovel 1 is working, the control system of the electric shovel first judges the working status of the pushing mechanism based on the real-time detected rate of change of the pushing motor speed in the pushing mechanism 3, that is, the magnitude of the force on the pushing mechanism during the digging process. If the bucket is subject to greater resistance, it will bite the bottom (e.g. Figure 2The shaded area in the digging path of the middle bucket 3 is used to identify the digging status (such as whether the digging status of the electric shovel is normal, whether the digging process is smooth, etc.) based on the difference between the speed setting and the actual speed of the lifting mechanism and the pushing mechanism. The forward torque of the pushing mechanism is controlled according to formula (1).

[0049]

[0050] (1) The meaning of each letter in the formula is as follows: dv / dt: the rate of change of speed of the pushing mechanism, and the range of the rate of change of speed is 0-5;

[0051] K: Torque adjustment coefficient, calculated as: K=1 / (dv / dt);

[0052] T 推前限幅 : Limitation of the forward torque of the pushing mechanism;

[0053] T 推最大 Maximum torque limit of the pushing mechanism;

[0054] V 提给 : Improve mechanism speed settings;

[0055] V 提实 : Increase the actual speed of the mechanism;

[0056] V 推给 : Pushing mechanism speed setting;

[0057] V 推实 Actual speed of the pushing mechanism;

[0058] V 推额 Rated speed of the pressing mechanism;

[0059] V 提额 : Increase the rated speed of the mechanism;

[0060] Specifically, according to the above formula (1), when digging encounters significant resistance (such as root erosion), dv / dt ≥ 2, the electric shovel's control system reduces the forward torque of the pushing mechanism, thus making the digging process smoother and more efficient. Furthermore, when dv / dt < 2, V 提给 -V 提实 ≤V 提额 ×5%, V 推给 -V 推实 ≤V 推额 ×5% increases the forward torque of the pushing mechanism when dv / dt < 2, or V 提给 -V 提实 >V 提额 ×5% or V 推给 -V 推实 >V 推额×5%, maintaining the pushing torque, so that the electric shovel can correspond to different pushing torques for different working conditions, and the pushing speed is different when using different pushing torques, thus ensuring digging efficiency during the digging process, making the electric shovel more user-friendly and reducing vibration and energy consumption.

[0061] Furthermore, the shock-resistant control method of the electric shovel pushing mechanism of the present invention can not only effectively alleviate the vibration of the electric shovel by corresponding different pushing torque and pushing speed according to different working conditions and solve the problem of the boom, but also improve the full bucket rate and the adaptive digging ability of the electric shovel. In addition, this function is automatically controlled by the program, which also reduces the labor intensity of the driver.

[0062] In summary, the control method of this invention achieves impact resistance control of the electric shovel's pushing mechanism by real-time detection of the speed change rate dv / dt of the electric shovel's pushing motor during operation; comparing the real-time detected speed change rate with a preset value; and adjusting the pushing force of the electric shovel's pushing mechanism according to the magnitude of the speed change rate. This allows the electric shovel to adapt to different pushing torques under different working conditions, and the pushing speed varies with different pushing torques, thus ensuring digging efficiency during excavation. This also makes the electric shovel operation more user-friendly, reducing vibration and energy consumption.

[0063] Example 2

[0064] The present invention also provides an impact-resistant control system for an electric shovel pushing mechanism, comprising:

[0065] The detection module is used to detect the rate of change of speed dv / dt of the excavator's push motor in real time;

[0066] The comparison module is used to compare the real-time detected rate of change of speed with a preset value;

[0067] The adjustment module is used to adjust the pushing force of the electric shovel pushing mechanism based on the comparison results and the magnitude of the speed change rate dv / dt.

[0068] The above control system can control the vibration of the electric shovel during digging, while also improving the full bucket rate of the electric shovel and reducing the fatigue of the driver.

[0069] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Additionally, the terms "front," "back," "left," "right," "upper," and "lower" in this document refer to the placement shown in the accompanying drawings.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method of impact control for a shovels push mechanism, comprising: include: Real-time detection of the speed change rate dv / dt of the electric shovel's pushing motor; Compare the real-time detected rate of change of speed with a preset value; According to the comparison result and the speed change rate dv / dt, the pushing force of the electric shovel pushing mechanism is adjusted, and if dv / dt is greater than a preset value, the pushing force of the electric shovel pushing mechanism is: wherein, represents the maximum torque limit of the pushing mechanism, K represents a torque adjustment coefficient, and K=1 / (dv / dt).

2. The method for controlling the impact resistance of an electric shovel pushing mechanism according to claim 1, characterized in that, When adjusting the pushing force of the electric shovel's pushing mechanism based on the comparison results and the magnitude of the speed change rate: If dv / dt is greater than or equal to the preset value, the forward torque of the electric shovel pushing mechanism is reduced. If dv / dt is less than the preset value, the forward torque of the electric shovel pushing mechanism will be increased or maintained.

3. The method for controlling the impact resistance of an electric shovel pushing mechanism according to claim 2, characterized in that, The preset value is between 0 and 5.

4. The method for controlling the impact resistance of an electric shovel pushing mechanism according to claim 3, characterized in that, If dv / dt is less than the preset value, and the speed setting value of the lifting mechanism is also met at the same time... Compared with the actual value of the lifting mechanism speed The difference is less than or equal to the first speed preset value and the push mechanism speed setting value. Actual value of the pushing mechanism speed If the difference is less than or equal to the preset value of the second speed, then the pushing force of the electric shovel pushing mechanism is: .

5. The method for controlling the impact resistance of an electric shovel pushing mechanism according to claim 3, characterized in that, If dv / dt is less than the preset value, or meets the speed setting value of the lifting mechanism. Compared with the actual value of the lifting mechanism speed The difference is greater than the preset value of the first speed and the set value of the speed of the pushing mechanism. Actual value of the pushing mechanism speed If the difference is greater than any of the preset values ​​for the second speed, then the pushing force of the electric shovel pushing mechanism is: .

6. The method for controlling the impact resistance of an electric shovel pushing mechanism according to claim 4 or 5, characterized in that, The first speed preset value is and the second speed preset value ,in, Indicates the rated speed of the pressing mechanism. This indicates the rated speed of the booster mechanism.

7. The method for controlling the impact resistance of an electric shovel pushing mechanism according to claim 1 or 2, characterized in that, The velocity change rate dv / dt ranges from 0 to 5.

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