A multi-point discharge high voltage pulsed electrode device and method of use thereof

Abstract

This invention provides a multi-point discharge high-voltage pulse electrode device and its usage method. The device includes a positive electrode and a negative electrode; a positive insulating sleeve is fitted around the positive electrode, an electrode insulating component is fitted around the positive insulating sleeve, and a negative electrode is fitted around the electrode insulating component; the upper end of the positive electrode is connected to a positive connector, which is connected to the positive coaxial cable of a high-voltage pulse power supply; a negative fixing ring is fitted on the outer wall of the negative electrode, which is connected to a negative connector, which is connected to the negative coaxial cable of the high-voltage pulse power supply; the positive electrode can move up and down relative to the electrode insulating component along the axial direction. This invention achieves flexible configuration of the number of discharge points and the superposition effect of stress waves inside the rock, thereby significantly expanding the breaking range of a single pulse and improving rock breaking efficiency.

Description

Technical Field

[0001] This invention relates to the field of high-voltage pulse discharge rock breaking technology, and more particularly to a multi-point discharge high-voltage pulse electrode device and its usage method. Background Technology

[0002] High-voltage pulsed discharge rock breaking technology is a method that uses transient high voltage to create plasma channels within rock masses. These channels rapidly convert electrical energy into shock waves and stress waves, thereby driving the initiation, propagation, and eventual fracturing of cracks within the rock. Compared to traditional explosive blasting, this technology offers advantages such as controllable energy output, a smaller vibration impact range, and the absence of large amounts of harmful gases and dust, demonstrating promising application prospects in deep resource extraction and tunnel excavation.

[0003] However, existing electrode devices generally suffer from insufficient structural control and low reusability, making it difficult to simultaneously meet the requirements of different lithologies, media environments, and fracturing modes, thus hindering the engineering promotion of high-pressure pulse rock breaking technology. Especially in applications such as in-hole fracturing, surface spalling, and electrohydraulic coupling, existing devices still fall short in terms of gap adjustment, media adaptability, and ease of maintenance.

[0004] Therefore, it is necessary to propose a high-voltage pulse electrode device that features adjustable discharge gap, strong adaptability to medium environment, ability to achieve different crushing modes, and easy maintenance and replacement, so as to improve the applicability and engineering practicality of the device under complex rock crushing conditions. Summary of the Invention

[0005] To address the technical problems of single-point discharge leading to small rock fracturing areas, low rock-breaking efficiency, non-adjustable electrode spacing, and inconvenient electrode tip maintenance, this invention provides a multi-point discharge high-voltage pulse electrode device and its usage method. This invention primarily utilizes a positive electrode with an adjustable axial spacing and multiple negative electrodes to form a multi-point discharge structure. Replaceable metal wires and a detachable liquid medium shell are optionally installed at the electrode tips. This allows for flexible adjustment of the number of discharge points and electrode spacing, universal discharge under both gas and liquid media, and two working modes: borehole fracturing and rock surface spalling. This improves rock-breaking efficiency, reduces electrode maintenance costs, and enhances the ability to induce fracturing under differentiated dynamic loads on different rock types and working conditions.

[0006] The technical means employed in this invention are as follows:

[0007] A multi-point discharge high-voltage pulse electrode device includes a positive electrode and a negative electrode; The positive electrode is covered with a positive insulating sleeve, the positive insulating sleeve is covered with an electrode insulating component, and the electrode insulating component is covered with a negative electrode. The upper end of the positive electrode is connected to a positive connector, the positive connector is connected to the positive coaxial cable of the high-voltage pulse power supply, and a negative fixing ring is covered on the outer wall of the negative electrode. The negative fixing ring is connected to a negative connector, and the negative connector is connected to the negative coaxial cable of the high-voltage pulse power supply. The upper part of the electrode insulating component, the positive electrode insulating sleeve, and the positive electrode protrudes beyond the upper part of the negative electrode; the upper part of the positive electrode insulating sleeve and the positive electrode protrudes beyond the upper part of the electrode insulating component; and the lower part of the positive electrode insulating sleeve and the positive electrode protrudes beyond the lower end face of the negative electrode. The negative electrode is a hollow cylindrical structure. The lower end face of the cylindrical structure is provided with a number of protruding teeth evenly spaced along the circumference. The grooves between any two adjacent protruding teeth have the same shape and the same depth. The positive electrode can move up and down relative to the electrode insulating component along the axial direction.

[0008] Furthermore, several L-shaped branch electrodes extend from the lower sidewall of the positive electrode along the circumferential direction. Each L-shaped branch electrode consists of a horizontal arm and a vertical arm. One end of the horizontal arm is fixedly connected to the positive electrode, and the other end of the horizontal arm is connected to the lower end of the vertical arm. The vertical arm extends vertically upward and points towards a protrusion on the negative electrode. The number of L-shaped branch electrodes is equal to the number of protrusions on the negative electrode, and each L-shaped branch electrode and each protrusion is arranged in a one-to-one correspondence in the circumferential direction. There is a gap between the upper end of the L-shaped branch electrode and the lower end of the protrusion.

[0009] Furthermore, the positive electrode insulating sleeve and the electrode insulating component are made of either polytetrafluoroethylene or epoxy glass fiber tubing.

[0010] Furthermore, the number of L-shaped branch electrodes and protrusions ranges from 2 to 6, and the shape of the tips of the L-shaped branch electrodes and protrusions is one or a combination of conical, hemispherical or cylindrical.

[0011] Furthermore, the vertical arm of the L-shaped branch electrode is provided with scale lines.

[0012] Furthermore, the L-shaped branch electrode and the tip of the protruding tooth are connected by a metal wire, which is one of copper wire, aluminum wire, stainless steel wire, tungsten wire or nickel-chromium alloy wire.

[0013] Furthermore, the negative electrode is disposed inside the housing, and the gap between the negative electrode and the housing forms a discharge cavity. The discharge cavity is connected to the lower end of the injection tube, and a liquid blocking port is provided at the upper opening of the injection tube.

[0014] Furthermore, the shell is made of thermoplastic polyurethane elastomer material, and the cross-sectional shape of the shell is circular or square; the liquid injection tube and the liquid plug are made of polytetrafluoroethylene.

[0015] The present invention also provides a method for in-hole crushing using a multi-point discharge high-voltage pulse electrode device, which is based on any of the above-mentioned multi-point discharge high-voltage pulse electrode devices and includes the following steps: S1. Drill holes in the rock to be broken that match the outline of the electrode device, and clean the holes. S2. Depending on the rock breaking requirements, choose whether to install a metal wire between the L-shaped branch electrode and the tip of the tooth, and whether to set the negative electrode inside the shell and assemble a discharge cavity. If the shell is assembled, inject water or electrolyte into the discharge cavity through the injection pipe until the electrode working part is submerged, and then seal the injection pipe through the plugging port. If no metal wire is installed and no housing is assembled, S3 to S5 are executed directly to achieve multi-point discharge rock breaking in air medium; if a metal wire is installed but no housing is assembled, the metal wire is broken down and vaporized during the discharge process and induces the main discharge channel; if a housing is assembled and liquid medium is injected, multi-point discharge rock breaking in liquid-electric environment is achieved. S3. Insert the electrode device into the borehole so that the L-shaped branch electrode and the protrusion are both located within the target crushing area, and move the positive electrode along the axial direction to adjust the gap distance between the L-shaped branch electrode and the protrusion. S4. Connect the positive coaxial cable of the high-voltage pulse power supply to the positive connector, connect the negative coaxial cable of the high-voltage pulse power supply to the negative connector, and set the output voltage, pulse width and discharge count of the high-voltage pulse power supply. S5. Trigger high-voltage pulse discharge to form a multi-point discharge channel between the L-shaped branch electrode and the protruding tooth, thus completing the in-hole crushing of the rock.

[0016] The present invention also provides a method for using a multi-point discharge high-voltage pulse electrode device for rock surface peeling, based on any one of the above-mentioned multi-point discharge high-voltage pulse electrode devices, comprising the following steps: T1. Select the rock surface to be treated, and arrange the electrode end of the electrode device facing the rock surface, so that the L-shaped branch electrode and the protrusion tooth face the rock surface and maintain a gap with the rock surface. T2. Inject liquid medium between the tip of the L-shaped branch electrode and the protruding tooth and the rock surface to form a uniform medium layer. T3. Connect the positive coaxial cable of the high-voltage pulse power supply to the positive connector, and connect the negative coaxial cable of the high-voltage pulse power supply to the negative connector. Set the output voltage, pulse width, and discharge count of the high-voltage pulse power supply. T4 triggers a high-voltage pulse discharge, causing cracks to form on the rock surface and leading to spalling under the action of multi-point discharge.

[0017] Compared with the prior art, the present invention has the following advantages: The multi-point discharge structure provided by this invention has an L-shaped branch electrode at the lower end of the positive electrode and a tooth at the lower end of the negative electrode arranged in a one-to-one correspondence with each other and the number of branches is adjustable. By cooperating with a high-voltage pulse power supply, an independent discharge channel is formed between multiple tips, which realizes the flexible configuration of the number of discharge points and the superposition effect of stress waves inside the rock, thereby significantly expanding the breaking range of a single pulse and improving the rock breaking efficiency.

[0018] The structure provided by this invention allows the positive electrode to move up and down relative to the electrode insulator along the axial direction. By cooperating with the scale lines on the vertical arm of the L-shaped branch electrode, it enables precise and visual adjustment of the discharge gap between the positive and negative electrodes. This allows for the application of differentiated dynamic loads to induce fracturing for different rock types and fracturing requirements, thereby enhancing the adaptability of the device to different operating conditions.

[0019] The replaceable metal wire provided by this invention is installed between the L-shaped branch electrode and the tip of the tooth. By cooperating with the preferential breakdown vaporization characteristics in the high-voltage pulse discharge process, it induces the formation of a stable main discharge channel and reduces the ablation loss of the electrode body, thus realizing rapid maintenance and low-cost reuse of the electrode device.

[0020] The sealed discharge cavity formed by the shell, injection pipe and plugging port provided by the present invention, in conjunction with the injected water or electrolyte, completely immerses the working part of the electrode in the liquid medium, realizing the efficient conversion of shock waves in a liquid-electric environment, thereby further improving the crushing effect of hard rocks.

[0021] The invention provides a dual-mode design where the same electrode device can be inserted into the borehole to achieve in-hole breaking or placed on the rock surface to achieve surface stripping. By combining it with two different usage methods, the rock breaking equipment is made universal and multifunctional, reducing construction costs and simplifying on-site operation procedures. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of the device of the present invention.

[0024] Figure 2This is a schematic diagram of the structure of the present invention with an L-shaped branch electrode.

[0025] Figure 3 This is a top view of the device of the present invention.

[0026] Figure 4 for Figure 2 A bottom view.

[0027] Figure 5 for Figure 2 Schematic diagram of the metal wire connecting the device.

[0028] Figure 6 This is a schematic diagram of the present invention in conjunction with the housing.

[0029] Figure 7 This is a schematic diagram of the device used for in-hole crushing according to the present invention.

[0030] Figure 8 This is a schematic diagram illustrating the use of the device of the present invention for rock surface peeling.

[0031] In the diagram: 1. Positive electrode connector; 2. Positive electrode insulating sleeve; 3. Electrode insulating component; 4. Negative electrode connector; 5. Negative electrode retaining ring; 6. Negative electrode; 7. Positive electrode; 8. Metal wire; 9. Liquid blocking port; 10. Liquid injection tube; 11. Housing; 12. L-shaped branch electrode; 13. Convex tooth. Detailed Implementation

[0032] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0035] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0036] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0037] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0038] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0039] like Figure 1 As shown, this invention provides a multi-point discharge high-voltage pulse electrode device, including a positive electrode 7 and a negative electrode 6. A positive insulating sleeve 2 is fitted around the positive electrode 7, an electrode insulating component 3 is fitted around the positive insulating sleeve 2, and the negative electrode 6 is fitted around the electrode insulating component 3. The upper end of the positive electrode 7 is connected to a positive connector 1, which is used to connect to the positive coaxial cable of a high-voltage pulse power supply. The outer wall of the negative electrode 6 is connected to a negative connector 4, which is used to connect to the negative coaxial cable of a high-voltage pulse power supply.

[0040] The upper parts of the electrode insulating component 3, the positive electrode insulating sleeve 2, and the positive electrode 7 protrude from the upper part of the negative electrode 6. The upper parts of the positive electrode insulating sleeve 2 and the positive electrode 7 protrude from the upper part of the electrode insulating component 3. The lower parts of the positive electrode insulating sleeve 2 and the positive electrode 7 protrude from the lower end face of the negative electrode 6.

[0041] The negative electrode 6 is a hollow cylindrical structure. The lower end face of this cylindrical structure has several evenly spaced protrusions 13 along the circumference, and the grooves between any two adjacent protrusions 13 have the same shape and equal depth. The positive electrode 7 can move up and down relative to the electrode insulator 3 along the axial direction. In practical applications, the positive electrode connector 1, negative electrode connector 4, negative electrode retaining ring 5, negative electrode 6, and positive electrode 7 can all be made of copper or aluminum, which have good conductivity.

[0042] The positive electrode insulating sleeve 2 and the electrode insulating component 3 are made of either polytetrafluoroethylene (PTFE) or epoxy fiberglass tubing, with PTFE being preferred to ensure sufficient insulation strength and mechanical support.

[0043] like Figure 2-4 As shown, as a further improvement, several L-shaped branch electrodes 12 extend from the lower sidewall of the positive electrode 7 in a circumferential direction. Each L-shaped branch electrode 12 consists of a horizontal arm and a vertical arm. One end of the horizontal arm is fixedly connected to the positive electrode 7, and the other end of the horizontal arm is connected to the lower end of the vertical arm. The vertical arm extends vertically upward and points towards a protrusion 13 on the negative electrode 6. The number of L-shaped branch electrodes 12 is equal to the number of protrusions 13 on the negative electrode 6, and each L-shaped branch electrode 12 and each protrusion 13 are arranged in a one-to-one correspondence in the circumferential direction. There is a gap between the upper end of the L-shaped branch electrode 12 and the lower end of the protrusion 13, which is the discharge gap.

[0044] The number of L-shaped branch electrodes 12 and protruding teeth 13 ranges from 2 to 6, and is preferably 4 in this embodiment. The tip shape of the L-shaped branch electrodes 12 and protruding teeth 13 is one or a combination of conical, hemispherical or cylindrical. In this embodiment, the tip shape is conical to facilitate electric field concentration.

[0045] To facilitate precise adjustment of the discharge gap, a scale is provided on the vertical arm of the L-shaped branch electrode 12. The user can rotate the positive electrode 7 to move it axially, and read and set the distance between the end of the L-shaped branch electrode 12 and the lower end of the protrusion 13 according to the scale.

[0046] like Figure 5 As shown, the tips of the L-shaped branch electrode 12 and the protruding tooth 13 can also be connected by a metal wire 8. The metal wire 8 is one of copper wire, aluminum wire, stainless steel wire, tungsten wire, or nickel-chromium alloy wire. Under the action of a high-voltage pulse, the metal wire 8 is first broken down and vaporized, forming a low-resistance conductive channel, inducing the main discharge. The metal wire 8 is a consumable material and can be quickly replaced after melting.

[0047] like Figure 6 As shown, based on the above structure, the negative electrode 6 is disposed inside the housing 11. The gap between the negative electrode 6 and the housing 11 forms a discharge cavity. The discharge cavity is connected to the lower end of the injection tube 10, and a plugging port 9 is provided at the upper opening of the injection tube 10. The housing 11 is made of thermoplastic polyurethane elastomer material, which has good elasticity to adapt to drill holes of different shapes. The cross-sectional shape of the housing 11 is circular or square, and circular is preferred in this embodiment. The injection tube 10 and the plugging port 9 are made of polytetrafluoroethylene.

[0048] In use, water or electrolyte is injected into the discharge cavity through the injection tube 10 until the liquid submerges the working part of the electrode. Then, the injection tube 10 is sealed with the plug 9 to form a closed liquid-electric discharge environment.

[0049] like Figure 7 As shown, this embodiment provides a method for in-hole crushing using a multi-point discharge high-voltage pulse electrode device, which is implemented based on the multi-point discharge high-voltage pulse electrode device.

[0050] The specific steps are as follows: S1. Drill holes in the rock to be broken that match the outer contour of the electrode device. The hole diameter is slightly larger than the outer contour of the electrode device, and the hole depth is determined according to the rock breaking range. Clean the holes.

[0051] S2. Depending on the rock-breaking requirements, select whether to install a metal wire 8 between the tips of the L-shaped branch electrode 12 and the protruding tooth 13, and whether to place the negative electrode 6 inside the housing 11 and assemble the discharge cavity. If the housing 11 is assembled, inject water or electrolyte into the discharge cavity through the injection pipe 10 until the electrode working part is submerged, and then seal the injection pipe 10 through the plugging port 9. If the metal wire 8 is not installed and the housing 11 is not assembled, proceed directly to the subsequent steps to achieve multi-point discharge rock-breaking in the air medium. If the metal wire 8 is installed but the housing 11 is not assembled, the metal wire 8 is broken down and vaporized during the discharge process, inducing the main discharge channel. If the housing 11 is assembled and a liquid medium is injected, multi-point discharge rock-breaking in a liquid-electric environment is achieved.

[0052] S3. Insert the electrode device into the borehole, ensuring that both the L-shaped branch electrode 12 and the protruding tooth 13 are within the target crushing area. Move the positive electrode 7 axially to adjust the gap between the L-shaped branch electrode 12 and the protruding tooth 13. Precise adjustment can be achieved by observing the scale lines on the vertical arm of the L-shaped branch electrode 12.

[0053] S4. Connect the positive coaxial cable of the high-voltage pulse power supply to positive connector 1, and connect the negative coaxial cable of the high-voltage pulse power supply to negative connector 4. Set the output voltage, pulse width, and discharge count of the high-voltage pulse power supply. Specific parameters should be determined according to the rock type and crushing requirements.

[0054] S5. Trigger high-voltage pulse discharge to form a multi-point discharge channel between the L-shaped branch electrode 12 and the protruding tooth 13. During the discharge process, multiple plasma channels are generated between the positive electrode 7 and the negative electrode 6. The shock waves superimposed on the rock, completing the in-hole crushing of the rock. After completing the predetermined number of discharges, turn off the high-voltage pulse power supply, perform discharge grounding treatment on the electrode device, and then pull the electrode device out of the borehole to check the ablation of the electrode and the metal wire 8. If necessary, grind or replace them.

[0055] like Figure 8 As shown, this embodiment provides a method for using a multi-point discharge high-voltage pulse electrode device to peel off rock surfaces. This method is based on the multi-point discharge high-voltage pulse electrode device and does not require the assembly of a housing.

[0056] The specific steps are as follows: T1. Select the rock surface area to be treated, and perform simple grinding if necessary to ensure that the electrodes can adhere well to the rock surface. Arrange the electrode ends of the electrode device towards the rock surface, so that both the L-shaped branch electrode 12 and the protruding teeth 13 face the rock surface and maintain a certain gap from the rock surface.

[0057] T2. A liquid medium, such as water or electrolyte, is injected between the tip of the L-shaped branch electrode 12 and the protrusion 13 and the rock surface to form a uniform dielectric layer. This dielectric layer facilitates the efficient transfer of discharge energy to the rock surface.

[0058] T3. Connect the positive coaxial cable of the high-voltage pulse power supply to the positive connector 1, and connect the negative coaxial cable of the high-voltage pulse power supply to the negative connector 4. Set the output voltage, pulse width, and discharge count of the high-voltage pulse power supply.

[0059] T4. Trigger a high-voltage pulse discharge, causing cracks and spalling on the rock surface under multi-point discharge. If the fracturing effect is not as expected after one discharge, a second or multiple discharges can be performed. After the discharge is completed, the device is grounded to release the remaining electrical energy and the electrode device is recovered.

[0060] 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 or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-point discharge high-voltage pulse electrode device, characterized in that, Includes positive and negative electrodes; The positive electrode is covered with a positive insulating sleeve, the positive insulating sleeve is covered with an electrode insulating component, and the electrode insulating component is covered with a negative electrode. The upper end of the positive electrode is connected to a positive connector, the positive connector is connected to the positive coaxial cable of the high-voltage pulse power supply, and a negative fixing ring is covered on the outer wall of the negative electrode. The negative fixing ring is connected to a negative connector, and the negative connector is connected to the negative coaxial cable of the high-voltage pulse power supply. The upper part of the electrode insulating component, the positive electrode insulating sleeve, and the positive electrode protrudes beyond the upper part of the negative electrode; the upper part of the positive electrode insulating sleeve and the positive electrode protrudes beyond the upper part of the electrode insulating component; and the lower part of the positive electrode insulating sleeve and the positive electrode protrudes beyond the lower end face of the negative electrode. The negative electrode is a hollow cylindrical structure. The lower end face of the cylindrical structure is provided with a number of protruding teeth evenly spaced along the circumference. The grooves between any two adjacent protruding teeth have the same shape and the same depth. The positive electrode can move up and down relative to the electrode insulating component along the axial direction.

2. The high-voltage pulse electrode device for multi-point discharge according to claim 1, characterized in that, The lower sidewall of the positive electrode extends into several L-shaped branch electrodes along the circumferential direction. Each L-shaped branch electrode consists of a horizontal arm and a vertical arm. One end of the horizontal arm is fixedly connected to the positive electrode, and the other end of the horizontal arm is connected to the lower end of the vertical arm. The vertical arm extends vertically upward and points towards a protrusion on the negative electrode. The number of L-shaped branch electrodes is equal to the number of protrusions on the negative electrode, and each L-shaped branch electrode and each protrusion is arranged in a one-to-one correspondence in the circumferential direction. There is a gap between the upper end of the L-shaped branch electrode and the lower end of the protrusion.

3. The multi-point discharge high-voltage pulse electrode device according to claim 1, characterized in that, The positive electrode insulating sleeve and electrode insulating component are made of either polytetrafluoroethylene or epoxy glass fiber tubing.

4. The multi-point discharge high-voltage pulse electrode device according to claim 2, characterized in that, The number of L-shaped branch electrodes and protrusions ranges from 2 to 6, and the shape of the tip of the L-shaped branch electrodes and protrusions is one or a combination of conical, hemispherical or cylindrical.

5. The multi-point discharge high-voltage pulse electrode device according to claim 2, characterized in that, The vertical arm of the L-shaped branch electrode is provided with scale lines.

6. The multi-point discharge high-voltage pulse electrode device according to claim 2, characterized in that, The L-shaped branch electrode and the tip of the protruding tooth are connected by a metal wire, which is one of copper wire, aluminum wire, stainless steel wire, tungsten wire or nickel-chromium alloy wire.

7. The multi-point discharge high-voltage pulse electrode device according to claim 1, characterized in that, The negative electrode is disposed inside the housing, and the gap between the negative electrode and the housing forms a discharge cavity. The discharge cavity is connected to the lower end of the injection tube, and a liquid blocking port is provided at the upper opening of the injection tube.

8. The multi-point discharge high-voltage pulse electrode device according to claim 7, characterized in that, The shell is made of thermoplastic polyurethane elastomer material, and the cross-sectional shape of the shell is circular or square; the liquid injection tube and the liquid plug are made of polytetrafluoroethylene.

9. A method for in-hole breaking of a multi-point discharge high-voltage pulse electrode device, implemented based on the multi-point discharge high-voltage pulse electrode device according to any one of claims 1-8, characterized in that, Includes the following steps: S1. Drill holes in the rock to be broken that match the outline of the electrode device, and clean the holes. S2. Depending on the rock breaking requirements, choose whether to install a metal wire between the L-shaped branch electrode and the tip of the tooth, and whether to set the negative electrode inside the shell and assemble a discharge cavity. If the shell is assembled, inject water or electrolyte into the discharge cavity through the injection pipe until the electrode working part is submerged, and then seal the injection pipe through the plugging port. If no metal wire is installed and no housing is assembled, S3 to S5 are executed directly to achieve multi-point discharge rock breaking in air medium; if a metal wire is installed but no housing is assembled, the metal wire is broken down and vaporized during the discharge process and induces the main discharge channel; if a housing is assembled and liquid medium is injected, multi-point discharge rock breaking in liquid-electric environment is achieved. S3. Insert the electrode device into the borehole so that the L-shaped branch electrode and the protrusion are both located within the target crushing area, and move the positive electrode along the axial direction to adjust the gap distance between the L-shaped branch electrode and the protrusion. S4. Connect the positive coaxial cable of the high-voltage pulse power supply to the positive connector, connect the negative coaxial cable of the high-voltage pulse power supply to the negative connector, and set the output voltage, pulse width and discharge count of the high-voltage pulse power supply. S5. Trigger high-voltage pulse discharge to form a multi-point discharge channel between the L-shaped branch electrode and the protruding tooth, thus completing the in-hole crushing of the rock.

10. A method for using a multi-point discharge high-voltage pulse electrode device to exfoliate rock surfaces, implemented based on the multi-point discharge high-voltage pulse electrode device according to any one of claims 1 to 8, characterized in that... Includes the following steps: T1. Select the rock surface to be treated, and arrange the electrode end of the electrode device facing the rock surface, so that the L-shaped branch electrode and the protrusion tooth face the rock surface and maintain a gap with the rock surface. T2. Inject liquid medium between the tip of the L-shaped branch electrode and the protruding tooth and the rock surface to form a uniform medium layer. T3. Connect the positive coaxial cable of the high-voltage pulse power supply to the positive connector, and connect the negative coaxial cable of the high-voltage pulse power supply to the negative connector. Set the output voltage, pulse width, and discharge count of the high-voltage pulse power supply. T4 triggers a high-voltage pulse discharge, causing cracks to form on the rock surface and leading to spalling under the action of multi-point discharge.

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