Device and method for automatically identifying the health status of bucket teeth of bucket wheel excavator

Abstract

A device and method for automatically identifying the health status of bucket teeth of a bucket wheel excavator, relating to the field of open-pit coal mining. The method uses an infrared photoelectric induction sensor diffuse reflection proximity switch to monitor the bucket teeth. Every time the bucket teeth rotate one circle and pass through the bucket wheel shielding plate, the collected switch data will be judged. If the switch data changes, it is judged that the bucket teeth are at risk of falling off. The method can give an early warning of whether the bucket teeth will fall off, reduce the cause of shutdowns, and ensure the safe and reliable production process. The equipment used in the method is simple, easy to implement, low-cost, easy to deploy and install, and provides a solid foundation for safe mining in mines.

Description

Technical Field

[0001] The present invention relates to the field of open-pit coal mining, and in particular to a device and method for automatically identifying the health status of bucket teeth of a bucket wheel excavator. Background Art

[0002] Bucket wheel excavators are mainly used in open-pit coal mining. However, due to the complex coal seam conditions in open-pit coal mines, there is the presence of gangue. This has a great impact on the normal operation of bucket wheel excavators. Once the bucket teeth break or fall off, they may cut the belt of the bucket receiving arm, the belt of the discharge arm, the belt of the belt conveyor, etc., causing the continuous system of the bucket wheel to stop production, and a series of safety hazards will occur later. Summary of the invention

[0003] In view of the deficiencies in the prior art, an object of the present invention is to provide a device and method for automatically identifying the health status of bucket teeth of a bucket wheel excavator.

[0004] The technical solution adopted by the present invention is: a device for automatically identifying the health status of bucket teeth of a bucket wheel excavator, including a PLC controller, and its technical key points are: including an adjustment bracket and an infrared photoelectric sensor diffuse reflection proximity switch installed on the adjustment bracket, the adjustment bracket is fixed on the bucket wheel and is located above the bucket wheel body baffle plate, the adjustment bracket includes a triangular support frame and a mounting plate with a mounting hole, one vertex of the support frame is welded to one end of the mounting plate, and the other end of the mounting plate is welded to the bottom edge corresponding to the vertex of the support frame; the infrared photoelectric sensor diffuse reflection proximity switch is installed in the mounting hole of the mounting plate, and the infrared photoelectric sensor diffuse reflection proximity switch is communicatively connected to the PLC controller.

[0005] A method for automatically identifying the health status of bucket teeth of a bucket wheel excavator comprises the following steps:

[0006] Adjust the angle of the infrared photoelectric sensor diffuse reflection proximity switch so that each infrared photoelectric sensor diffuse reflection proximity switch corresponds to each bucket tooth on the bucket wheel body that enters the monitoring range; arrange a central infrared photoelectric sensor diffuse reflection proximity switch separately, and its angle is consistent with the two infrared photoelectric sensor diffuse reflection proximity switches located near it and in the center, so as to monitor the switch value in the direction between the two central teeth on the bucket that is not blocked by the blocking objects;

[0007] The steps of obtaining the switch quantity data of the infrared photoelectric induction sensor diffuse reflection proximity switch in real time are as follows: first, manually measure the distance L between the bucket wheel body shielding plate and the bucket tooth closest to the wheel bucket; then obtain the bucket tooth thickness h; adjust the proximity switch monitoring distance N, and if N satisfies L≤N≤L+h, start data collection;

[0008] The steps of data fusion and processing: real-time collection of the wheel bucket self-rotation speed and self-rotation current data; fusing the collected switch quantity data and time data with the above wheel bucket self-rotation speed and self-rotation current data to form an array, and storing it by the time step method;

[0009] Steps to determine the health status of bucket teeth; specifically include:

[0010] Compare the switch values ​​collected by the diffuse reflection proximity switch of the central infrared photoelectric sensor in the same array. After one cycle, if the remaining data in the array within this period of time is 0, it is considered that the bucket tooth at this position has fallen or is damaged.

[0011] The magnitude of the external force on the bucket is calculated based on the bucket wheel rotation speed and rotation current. If the force on the bucket teeth suddenly increases, that is, one of the bucket wheel rotation speed and current suddenly increases, reaching the maximum shearing and bending resistance of the bucket teeth, it can be indirectly determined that the bucket teeth have fallen off or are damaged;

[0012] The step of feeding back real-time information is to feed back the health status judgment information of the bucket wheel teeth to the bucket wheel driver in real time, and remind the driver in the form of early warning and forecast. If the problem is more serious, the driver can be reminded to stop the machine for inspection at any time to reduce the failure rate of the bucket wheel.

[0013] The above scheme includes the following steps: when storing by the event step method, if after one cycle, the fused data has data that changes from 0 to 1 or from 1 to 0, the original data is stored; otherwise, it is not stored.

[0014] The beneficial effects of the present invention are as follows: the device and method for automatically identifying the health status of bucket teeth of a bucket wheel excavator uses an infrared photoelectric induction sensor diffuse reflection proximity switch to monitor the bucket teeth. Every time the bucket teeth rotate one circle and pass through the bucket wheel shielding plate, the collected switch data will be judged. If the switch data changes, it is judged that the bucket teeth are at risk of falling off. This method can give an early warning of whether the bucket teeth will fall off, reduce the cause of shutdowns, and ensure the safe and reliable production process. The equipment used in this method is simple, easy to implement, low cost, easy to deploy and install, and provides a solid foundation for safe mining in mines. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1It is a structural schematic diagram of a bucket wheel excavator in an embodiment of the present invention;

[0017] Figure 2 It is an enlarged schematic diagram of a bucket tooth and a proximity switch in an embodiment of the present invention;

[0018] Figure 3 Schematic diagram of the bucket teeth structure on the bucket wheel in an embodiment of the present invention;

[0019] Figure 4 This is a schematic diagram of the structure of the adjusting bracket in an embodiment of the present invention;

[0020] Figure 5 Flow chart of a method for automatically identifying the health status of bucket teeth of a bucket wheel excavator in an embodiment of the present invention;

[0021] The serial numbers in the figure are explained as follows: 1 infrared photoelectric induction sensor diffuse reflection proximity switch, 2 adjustment bracket, 21 triangular support frame, 22 mounting plate, 3 bucket teeth, 4 bucket wheel body shielding plate, 5 wheel bucket. DETAILED DESCRIPTION

[0022] To make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the following is a brief description of the present invention in conjunction with the attached Figure 1 to Figure 5 The present invention is further described in detail with reference to the accompanying drawings and specific embodiments.

[0023] The method for automatically identifying the health status of bucket teeth of a bucket wheel excavator adopted in this embodiment includes:

[0024] Step 1, the steps to install the infrared photoelectric sensor diffuse reflection proximity switch.

[0025] This embodiment is described by taking the DWY2000 bucket wheel excavator of Xinjiang Naomaohu Jiangna Xingsheng open-pit coal mine as an example, wherein the bucket wheel excavator has 18 buckets, each bucket has 6 bucket teeth 3, which are represented by X1, X2, X3, X4, X5 and X6 respectively. Due to the working nature of the bucket wheel excavator, the bucket teeth evenly distributed on the bucket are not arranged in a uniform vertical position, but the 6 bucket teeth 3 are distributed and symmetrically distributed, so in order to collect the health status of the 6 bucket teeth at the same time, it is necessary to use the adjustment bracket 2 to adjust the angle of the infrared photoelectric induction sensor diffuse reflection proximity switch 1 (hereinafter referred to as the proximity switch), the adjustment bracket 2 is fixed on the bucket wheel 5 and located above the bucket wheel body shielding plate 4, mainly composed of a triangular support frame 21 and a mounting plate 22 with 6 mounting holes, one vertex of the support frame 21 is welded to one end of the mounting plate 22, and the other end of the mounting plate 22 is welded to the bottom edge corresponding to the vertex of the support frame 21; the proximity switch is installed in the mounting hole of the mounting plate 22.

[0026] The adjusting bracket 2 in this embodiment utilizes the stability principle of a triangle, and can also prevent the proximity switch from being damaged due to vibration of the bucket wheel body shielding plate 4.

[0027] A proximity switch perpendicular to the bucket tooth 3 is installed above the bucket wheel body shield plate 4 and at the horizontal midline position of each bucket tooth 3. The six proximity switches in this embodiment are represented by Y1, Y2, Y3, Y4, Y5 and Y6 respectively. Based on the acquisition time of the two bucket teeth X3 and X4, the angles of the four proximity switches Y1, Y2, Y5 and Y6 are deflected, and the vertical distance between each proximity switch and the bucket wheel body shield plate 4 is manually measured: after measurement in this embodiment, the vertical distance between the two bucket teeth X3 and X4 and the bucket wheel body shield plate 4 is 44.2cm, the vertical distance between the two bucket teeth X2 and X5 and the bucket wheel body shield plate 4 is 51.3cm, and the vertical distance between the two bucket teeth X1 and X6 and the bucket wheel body shield plate 4 is 64.5cm. The shortest distance between the bucket wheel body shield plate 4 and the next bucket is 90cm. Moreover, the vertical thickness of the bucket tooth is 2 cm, and the length of the bucket tooth 3 is 32 cm, so the monitoring distance of the two proximity switches Y3 and Y4 is 46 cm, the monitoring distance of the two proximity switches Y2 and Y5 is 53 cm, and the monitoring distance of the two proximity switches Y1 and Y6 is 66 cm, to ensure that at the same time, each proximity switch is perpendicular to the bucket tooth 3 measured by each of them.

[0028] Step 2: real-time acquisition of switch quantity data.

[0029] (1) The six proximity switches in this embodiment collect the switch signals of each bucket tooth 3 passing through the bucket wheel body baffle 4. If there is a return signal, the switch signal is 1, and the bucket tooth 3 is considered to be normal; if there is no return signal, the switch signal is 0, and the bucket tooth 3 is considered to be detached.

[0030] (2) A proximity switch Z is added above the bucket wheel shield plate 4, at the horizontal position between the two bucket teeth Y3 and Y4, which is used as a reference for the other 6 proximity switches. The real-time data of the above 7 proximity switches and the current time T are recorded in the form of an array as Ai (T, Y1, Y2, Y3, Y4, Y5, Y6, Z) (where i = 1, ..., 18) and stored in the data table. Then it is transmitted to the Siemens PLC of the electric control cabinet through a wireless data transmission radio, and the data is transmitted to the Siemens database on the server side using optical fiber communication.

[0031] Step 3: perform data fusion and preprocessing.

[0032] (1) The steps of collecting the bucket wheel rotation speed n and rotation current data I in real time.

[0033] The bucket wheel excavator uses EPEC controller to integrate various lines. The PWM port in the EPEC controller outputs the bucket wheel rotation speed n and current I. The PWM signal is first converted into 4-20mA analog data, and then transmitted to the Siemens PLC in the electric control cabinet through a wireless data transmission radio. The data is transmitted to the Siemens database on the server side using optical fiber communication. The rotation speed n, current I and current time T are recorded in the form of an array as Bj(T,n,I) (where j=0,1,2,...) and stored in the data table for data fusion.

[0034] (2) Steps for data fusion.

[0035] The data monitored by the 7 proximity switches collected are fused with the bucket wheel rotation speed n and the rotation current I through the collection time T as the common data point. The two arrays Ai(T, Y1, Y2, Y3, Y4, Y5, Y6, Z) (where i = 1, ..., 18) and Bj(T, n, I) (where j = 0, 1, 2, ...) are fused to form an array Ck(T, Y1, Y2, Y3, Y4, Y5, Y6, Z, n, I) (where k = 0, 1, 2, ...) containing 9 data points. The array stores data using the event step method. When the values ​​of Y1, Y2, Y3, Y4, Y5, Y6, Z in the array change, the storage function is triggered, and the data is stored in the data table for subsequent use in judging the health status of the bucket teeth.

[0036] Step 4, the step of judging the health status of bucket teeth.

[0037] If any of the following conditions is met, it can be considered that there is a problem with the health of the bucket teeth.

[0038] If the switch value collected by Y1, Y2, Y3, Y4, Y5, Y6 and Z in the same group, when the Z value is equal to 0, compare the other data during this period of time. If there is 1 in the Y1, Y2, Y3, Y4, Y5, Y6 data, it can be judged that the bucket tooth at the position showing 0 has fallen or is damaged. If the Z value changes from 0 to 1, and if the Y1, Y2, Y3, Y4, Y5, Y6 data are also 1, it can be judged that the proximity switch is blocked. This blockage may be caused by other parts of the bucket wheel blocking the proximity switch after the bucket wheel rotates. Therefore, this situation should not be used as the basis for judging whether the bucket tooth has fallen, and the data in the array should be discarded as noise data.

[0039] Based on the data collection of bucket wheel rotation speed n and rotation current I, according to the formula

[0040]

[0041] The voltage output by the bucket is U, and U is constant. According to the current I and the speed n, the magnitude of the external force F on the bucket can be obtained by reverse calculation:

[0042] F≈U×I×n

[0043] Since the wheel bucket 3 is affected by external factors during this period, part of the power will be offset, so only a rough value of the external force on the bucket can be obtained.

[0044] The magnitude of the external force on the bucket is calculated based on the bucket wheel rotation speed and rotation current. If the force on the bucket teeth suddenly increases, that is, one of the bucket wheel rotation speed and current suddenly increases, reaching the maximum shear force and bending force of the bucket teeth, it means that the impact state of the bucket teeth increases and the probability of bucket teeth breaking increases, which can indirectly determine that the bucket teeth have fallen or are damaged.

[0045] Step 5, determining the bucket tooth information and providing real-time feedback to the bucket wheel driver.

[0046] The above-mentioned information on the health status of the bucket teeth is fed back to the bucket driver in real time, and the driver is prompted in the form of an early warning forecast. If the problem is more serious, the driver can be prompted to stop the machine for inspection at any time to reduce the failure rate of the bucket.

[0047] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A device for automatically identifying the health status of bucket teeth of a bucket wheel excavator, comprising a PLC controller, characterized in that: It includes an adjustment bracket and an infrared photoelectric sensor diffuse reflection proximity switch installed on the adjustment bracket, the adjustment bracket is fixed on the wheel bucket and located above the bucket wheel body shielding plate, the adjustment bracket includes a triangular support frame and a mounting plate with a mounting hole, one vertex of the support frame is welded to one end of the mounting plate, and the other end of the mounting plate is welded to the bottom edge corresponding to the vertex of the support frame; the infrared photoelectric sensor diffuse reflection proximity switch is installed in the mounting hole of the mounting plate, and the infrared photoelectric sensor diffuse reflection proximity switch is connected to the PLC controller for communication; a central infrared photoelectric sensor diffuse reflection proximity switch is arranged separately, and its angle is consistent with the two infrared photoelectric sensor diffuse reflection proximity switches located near it and located in the center, which is used to monitor the switch value in the direction between the two central bucket teeth on the bucket that is not blocked by the shielding object.

2. A method for automatically identifying the health status of bucket teeth of a bucket wheel excavator, implemented by using the device for automatically identifying the health status of bucket teeth of a bucket wheel excavator as claimed in claim 1, characterized in that: The following steps are involved: Adjust the angle of the infrared photoelectric sensor diffuse reflection proximity switch so that each infrared photoelectric sensor diffuse reflection proximity switch corresponds to each bucket tooth on the bucket wheel body that enters the monitoring range; arrange a central infrared photoelectric sensor diffuse reflection proximity switch separately, and its angle is consistent with the two infrared photoelectric sensor diffuse reflection proximity switches located near it and in the center, so as to monitor the switch value in the direction between the two central teeth on the bucket that is not blocked by the blocking objects; The steps of obtaining the switch quantity data of the infrared photoelectric induction sensor diffuse reflection proximity switch in real time are as follows: first, manually measure the distance L between the bucket wheel body shielding plate and the bucket tooth closest to the wheel bucket; then obtain the bucket tooth thickness h; adjust the proximity switch monitoring distance N, and if N satisfies L≤N≤L+h, start data collection; The steps of data fusion and processing: real-time collection of the wheel bucket self-rotation speed and self-rotation current data; fusing the collected switch quantity data and time data with the above wheel bucket self-rotation speed and self-rotation current data to form an array, and storing it by the time step method; Steps to determine the health status of bucket teeth; specifically include: Compare the switch values ​​collected by the diffuse reflection proximity switch of the central infrared photoelectric sensor in the same array. After one cycle, if the data in the array is 0 during this period, it is considered that the bucket tooth at this position has fallen or is damaged. The magnitude of the external force on the bucket is calculated based on the bucket wheel rotation speed and rotation current. If the force on the bucket teeth suddenly increases, that is, one of the bucket wheel rotation speed and current suddenly increases, reaching the maximum shearing and bending resistance of the bucket teeth, it can be indirectly determined that the bucket teeth have fallen off or are damaged; The step of feeding back real-time information is to feed back the health status judgment information of the bucket wheel teeth to the bucket wheel driver in real time, and remind the driver in the form of early warning and forecast. If the problem is more serious, the driver can be reminded to stop the machine for inspection at any time to reduce the failure rate of the bucket wheel.

3. The method for automatically identifying the health status of bucket teeth of a bucket wheel excavator according to claim 2, characterized in that: The method comprises the following steps: when storing by the event step method, if after one cycle, the fused data has data changing from 0 to 1 or from 1 to 0, the original data is stored; otherwise, the original data is not stored.

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