WO1998007959A1

WO1998007959A1 - Method and device for crushing material by discharging pulsed electric energy and method and device for generating high-voltage pulse

Info

Publication number: WO1998007959A1
Application number: PCT/JP1997/002888
Authority: WO
Inventors: Tadayuki Hanamoto; Kazuyuki Sajiki; Koichiro Itow
Original assignee: Komatsu Ltd.
Priority date: 1996-08-22
Filing date: 1997-08-20
Publication date: 1998-02-26
Also published as: KR19980018739A; JPH1061371A

Abstract

A method for crushing material by discharging pulse electric energy by which preliminary holes for electrical crushing can be drilled into a material to be crushed and the material can be crushed with high workability and the electrical crushing can be performed efficiently. In the method, in which electrodes are inserted into preliminary holes (4) drilled into the material to be crushed and the material is crushed by discharging an electric current from the electrodes (4) by applying a high-voltage pulse across the electrodes (4) after the spaces in the holes around the electrodes (4) are filled up with a solution (9), the material is crushed by inserting the electrodes for crushing into the holes (4) and making a discharge current for crushing flow after the holes (4) are drilled into the material by making a discharge current for drilling flow from electrodes for drilling. The discharge current for drilling is made to flow through the material and the discharge current for crushing is made to flow through the solution.

Description

Description Method of crushing a substance by pulsed electric energy discharge, its crushing device, its high-voltage pulse generating method, and its high-voltage pulse generating device

The present invention relates to a method for crushing a substance such as a bedrock or a concrete by discharge of pulsed electric energy. Background technology

Conventionally, several methods have been proposed for crushing bedrock, concrete, and the like by discharging electric energy (hereinafter referred to as electric crushing).

In Japanese Unexamined Patent Publication No. Hei 4-2-2224, a solid insulator such as a rock is drilled with a drill or the like, and a viscous electrolytic solution (eg, copper sulfate electrolytic solution) is placed in the hole. In this state, a coaxial electrode is inserted into this hole, and a high-voltage pulse is applied to this electrode. As a result, a plasma discharge is generated at the electrode, and the electrical energy radiated at this time crushes the rocks and fragments them. Then, the inside of the confined area around the electrode is filled with the above-mentioned electrolytic solution so as to increase the destructive force generated by the plasma discharge. In addition, the rising time of the high voltage pulse is reduced to a predetermined value or less, so that the discharge current easily flows in the electrolyte.

In addition, Japanese Patent Publication No. Sho 62-5202733 discloses that two or more different holes are made at a predetermined distance in a substance such as rock, an electrode is inserted into each hole, and a different hole is formed. Rocks are crushed by plasma discharge between the electrodes. At this time, high-voltage energy is applied to the rock in a very short time in the form of a pulse, which causes crushing. In each of the publications, it is necessary to make a hole for inserting a crushing electrode in advance by another means (for example, a drill or the like). For this reason, when actually performing electro-crushing, it is necessary to separately prepare a means for drilling and a device for crushing. However, there is a problem that workability is not so good because it requires man-hours for setup change. In addition, Japanese Patent Publication No. Sho 62-5202733 states that the rising time of the applied high-voltage pulse must be within a predetermined time in order to efficiently perform the electrofracture. However, in order to perform electrocrushing practically, it is necessary to crush a large amount of substances in a short time, and a more efficient method is required. Therefore, as described above, the rise time of the high-voltage pulse is shortened to make the rocks and the like easily crushed, and the amount of electric energy input to the rocks and the like is increased in order to crush a large amount in a wide range. Need to be done.

Disclosure of the invention

The present invention has been made in view of such conventional problems, and has excellent workability of drilling and crushing a preliminary hole at the time of electric crushing, and crushing a substance by pulsed electric energy discharge capable of efficiently performing the electrocrushing. It is an object of the present invention to provide a method, a crushing device, a high-voltage pulse generating method, and a high-voltage pulse generating device. In the first invention of the method for crushing a substance by pulsed electric energy discharge according to the present invention, an electrode is inserted into a preliminary hole provided in a substance to be crushed, the periphery of the electrode is filled with a solution, and a high-voltage pulse is applied to the electrode. In the method of crushing a substance by pulse electric energy discharge in which the substance is crushed by a discharge current at the electrode, a preliminary hole is formed in the substance by passing a discharge current through the electrode for preliminary hole drilling. Thereafter, the electrode for crushing is inserted into the preliminary hole, and a discharge current is passed through the electrode for crushing to crush the substance.

As a result, since the excavation of the preliminary hole and the crushing using the preliminary hole are both performed by the electric crushing by the pulse electric energy discharge, efficient crushing can be performed.

A second invention is the crushing method according to the first invention, wherein a discharge current flows through the substance during the preliminary hole excavation, and a discharge current flows through the solution during the crushing. This allows a discharge current to flow through the material to be crushed during pre-drilling, so that this material is efficiently and deeply drilled. Also, when crushing, discharge Since the current flows, a shock wave is generated, and this shock wave crushes the material to be crushed in a wide range. As a result, it is possible to efficiently perform electrofracture by pulsed electric energy discharge.

According to a third invention, in the crushing method according to the first invention, a discharge current is increased in the substance or the solution by changing a rising time of the high voltage pulse between the preliminary hole excavation and the crushing. L or R

As described above, the characteristic that the breakdown voltage of the substance to be crushed and the withstand voltage of the solution are exchanged according to the rise time of the high-voltage pulse is used.By changing the rise time, the discharge current is reduced in the crushed substance. Or flowing in a solution. Therefore, when a preliminary hole is drilled, a discharge current flows through the material to be crushed, and this material is efficiently and deeply drilled. In addition, during crushing, a discharge current flows through the solution around the electrode, and the shock wave crushes the material to be crushed over a wide area. As a result, electric crushing can be performed efficiently.

According to a fourth invention, in the crushing method of the first invention, the tip of the electrode is brought into contact with the substance at the time of digging the preliminary hole, and a discharge current flows through the substance. Discharge current is flowing through the solution away from the substance. In this way, when the tip of the electrode is brought into contact with the material to be crushed, a discharge current flows through this material, so that deep drilling can be performed when drilling a preliminary hole. In addition, a shock current is generated by causing a discharge current to flow through the solution while separating the tip of the electrode from the substance to be crushed, and the substance to be crushed is widely crushed by the shock wave. As a result, electrocrushing can be performed efficiently.

According to a fifth aspect of the present invention, in the crushing method of the first aspect, at least two or more of the electrodes are used to drill at least two of the preliminary holes (4) at the time of digging the preliminary holes, and at least two of these The electrodes are inserted into the above-mentioned spare holes, and a high-voltage pulse is applied between these different electrodes.

In this way, at least two or more electrodes are used to make preliminary holes at the same time, and by discharging between different electrodes inserted into these different preliminary holes, the gap between the preliminary holes and the surrounding area is discharged. Can be crushed extensively.

The sixth invention of the apparatus for crushing a substance by pulsed electric energy discharge according to the present invention comprises: an electrode inserted into a preliminary hole formed in a substance to be crushed; a solution filling the periphery of the electrode; A pulse generator for applying a voltage pulse, wherein the substance is crushed by a discharge current at the electrode. An apparatus for crushing a substance by a Luz electrician energy discharge, comprising: the electrode for preliminary hole drilling; and the electrode for crushing. As described above, since the pre-hole drilling and the crushing are performed by using the electrode for the preliminary hole digging and the electrode for the crushing, respectively, and the crushing is performed by the electric crushing by the pulse electric energy discharge, the crushing can be performed efficiently.

A seventh aspect of the present invention is the crushing apparatus of the sixth aspect, further comprising a pulse generator for excavating a preliminary hole and outputting a frame that outputs the high-voltage pulse having a different rising time. As described above, the characteristic that the breakdown voltage of the substance to be crushed and the breakdown voltage of the solution are exchanged depending on the rise time of the high voltage pulse is used. A discharge current flows through the electrodes by means of pulse generators for pre-hole drilling and crushing, which output high voltage pulses with different rise times. As a result, a discharge current flows through the material to be crushed during preliminary hole drilling, and this material is efficiently and deeply drilled. In addition, a discharge current flows through the solution around the electrode during crushing, and the shock wave at this time crushes the crushed material over a wide range. As a result, electrocrushing can be performed efficiently.

According to an eighth invention, in the crushing apparatus of the sixth invention, the electrode and the pulse generator for preliminary hole drilling and crushing are shared during the preliminary hole drilling and crushing, respectively. Since the electrode for drilling and crushing and the pulse generator are shared during preliminary drilling and crushing, more efficient crushing can be performed. In this case, it is possible to switch the output waveform of the pulse generator between for preliminary hole drilling and crushing.

A ninth invention is the crushing device according to the sixth invention, wherein at least two or more of the electrodes for preliminary excavation for simultaneously drilling at least two or more of the preliminary holes; At least two crushing electrodes that are inserted into different preliminary holes and between which the high-voltage pulse is applied, between the electrodes inserted into the two or more different preliminary holes. The substance is crushed by passing a discharge current through it.

In this way, a preliminary hole is formed simultaneously with at least two or more electrodes, and discharge is performed between different crushing electrodes inserted into the different preliminary holes, so that a wide range can be crushed between the preliminary holes and the periphery thereof. .

A tenth invention of the high-voltage pulse generation method according to the present invention is a method of applying a high-voltage pulse to an electrode, and crushing or crushing a substance to be crushed by a discharge current at the electrode. In the high-voltage pulse generation method of the above, energy is stored in at least two capacitors having different capacitances at different terminal voltage values, respectively, and the energy of the condenser on the side where the high voltage is stored is insulated from a substance. After the electrode is discharged at the early stage of the discharge at the time of destruction, the energy of the capacitor stored at a lower voltage than the electrode is continuously discharged.

In this way, at the beginning of the discharge of the substance to be destroyed during insulation rupture, the energy of the capacitor accumulated at a high voltage is discharged to facilitate discharge. Then, by discharging a larger amount of energy stored at a lower voltage, the large amount of energy required for crushing can be input. Therefore, it is possible to perform electro-fracture efficiently.

The eleventh invention of the high-voltage pulse generator according to the present invention is directed to a method for crushing a substance by pulsed electric energy discharge in which a high-voltage pulse is applied to an electrode, and a substance to be crushed is excavated or crushed by a discharge current at the electrode. High voltage pulse generator of the above, two DC power supplies having different output voltage values, a first capacitor in which energy is stored from a high voltage power supply of the two DC power supplies, and a lower voltage. A second capacitor having energy stored therein from the power supply and having a capacity greater than the capacity of the first capacitor; and at least two or more capacitors discharging the energy stored in the first or second capacitor at the electrode. And a trigger switch circuit. Thus, capacitors with different capacities are provided, The first capacitor stores energy from the high voltage power supply, and the second capacitor, which has a larger capacitance than the first capacitor, stores energy from the lower voltage power supply. In the initial stage of discharge at the time of dielectric breakdown of the substance to be destroyed, capacitor energy accumulated at high voltage is discharged through the trigger switch circuit, making it easier to discharge.

. Thereafter, a larger amount of energy stored at a lower voltage is discharged by another trigger switch circuit, so that a large amount of energy required for crushing can be input. Therefore, it is possible to efficiently perform the electro-fracture.

The second invention of the high-voltage pulse generator according to the present invention is that a high-voltage pulse is applied to an electrode, and a substance is crushed by pulse electric energy discharge in which a substance to be crushed is excavated or crushed by a discharge current at the electrode. A high-voltage pulse generator, comprising: two DC power supplies having different output voltage values; a means for directly discharging the energy of a low-voltage power supply of the two DC power supplies from the electrode; and a higher-voltage power supply. A capacitor for storing energy from the capacitor, and a trigger switch circuit for discharging the energy stored in the capacitor at the electrode.

Thus, the higher the voltage, the more energy is stored in the capacitor from the DC power supply. At the initial stage of discharge at the time of dielectric breakdown of the substance to be destroyed, the energy of this capacitor is discharged via the trigger switch circuit, so that the discharge becomes easy. After that, the energy of the DC power source with the lower voltage is discharged through means (for example, a resistor) that directly discharges from the electrode, so that large energy required for crushing can be input. Therefore, it is possible to perform electro-fracture efficiently. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a configuration diagram of a crusher of a first embodiment according to the present invention.

FIG. 2 is an explanatory view of the operation of the crushing apparatus according to the first embodiment during excavation of a preliminary hole.

FIG. 3 is an operation explanatory view at the time of crushing according to the crushing device of the first embodiment.

FIG. 4 shows a circuit configuration diagram of the pulse generator of the second embodiment.

FIG. 5 is an example of an output voltage waveform diagram of the pulse generator of FIG. FIG. 6 is another example of the output voltage waveform diagram of the pulse generator of FIG.

FIG. 7 is a chart showing the relationship between the rise time of the pulse voltage and the withstand voltage of various insulators according to the present invention.

FIG. 8 shows a circuit configuration diagram of the pulse generator of the third embodiment.

FIG. 9 is an output voltage waveform diagram of the pulse generator of FIG.

FIG. 10 is an explanatory diagram of an example of how to use the electrodes in the third embodiment.

FIG. 11 is an explanatory diagram of an example of how to use another electrode in the third embodiment.

FIG. 12 is a circuit configuration diagram of a pulse generator according to a fourth embodiment of the present invention.

FIG. 13 is an output voltage waveform diagram of the pulse generator of FIG.

FIG. 14 is an explanatory diagram of an example of how to use the electrodes in the fifth embodiment.

FIG. 15 is an explanatory diagram of an example of how to use another electrode in the fifth embodiment. BEST MODE FOR CARRYING OUT THE INVENTION

Each embodiment according to the present invention will be described in detail with reference to the drawings.

First, a first embodiment will be described with reference to FIGS. As shown in FIG. 1, the electrode 1 is an electrode used for both pre-hole drilling and main crushing, and is connected to the pulse generator 10. The pulse generator 10 outputs a high-voltage pulse having a predetermined output waveform. The electrode 1 includes a cylindrical negative electrode 3 and a positive electrode 2 provided along the central axis of the negative electrode 3, and the positive electrode 2 and the negative electrode 3 are insulated by an insulator. The inside of the negative electrode 3 may be in a hollow state or may be filled with an insulator. The positive electrode 2 and the negative electrode 3 are connected to a pulse generator 10 respectively. The periphery of the front end of the electrode 1 is surrounded by a solution 9 having a predetermined insulation resistance.

FIG. 2 and FIG. 3 are explanatory diagrams of the operation of the present embodiment, and show the case of digging a preliminary hole and the case of crushing, respectively. When drilling a preliminary hole, as shown in Fig. 2, a high voltage pulse is applied by bringing the tip of the electrode 1 into contact with the surface of rock or the like. At this time, since the discharge current flowing between the positive electrode 2 and the negative electrode 3 flows in the rock, it is possible to reliably excavate a hole in the rock. Since this discharge current flows only in the vicinity of electrode 1, the drilled hole is Is a hole having substantially the same shape as the outer shape of. Therefore, this hole can be used as the spare hole 4. At the time of crushing, as shown in FIG. 3, the tip of the electrode 1 is separated from the bottom surface of the preliminary hole 4, and discharge is performed in the solution 9 filled in the preliminary hole 4. In this case, a shock wave is generated by the discharge current flowing through the solution 9, and the shock wave propagates through the solution 9 and spreads in the lateral direction of the preliminary hole 4. Crushed. Therefore, crushing can be performed efficiently.

Next, a second embodiment will be described with reference to FIGS. In the present embodiment, an example is shown in which the rise time of the high voltage pulse is controlled to control the path through which the discharge current flows.

The power supply 11 outputs a predetermined DC high voltage at a predetermined repetition frequency as shown in FIG. 4, and this output is applied to the capacitor 13 via the resistor 12. The terminal voltage of the capacitor 13 is applied to the capacitor 15 via the trigger switch circuit 14. The trig switch circuit 14 is composed of, for example, a switch for high voltage and high current such as a shunt tube, and an inductance (coil). Further, the terminal voltage of the capacitor 15 is applied to the capacitor 17 via the magnetic switch 16, and the terminal voltage of the capacitor 17 is applied to the capacitor 19 via the magnetic switch 18. Here, the magnetic switch 16, the capacitor 17, the magnetic switch 18, and the capacitor 19 constitute a pulse compression circuit, and the rising time of the rising of the input pulse voltage is shortened, and the pulse is sharpened. It changes the voltage.

An output switching switch 20 is provided on the output side of the pulse compression circuit, and a common terminal of the output switching switch 20 is connected to the positive electrode 2 of the electrode 1. One of the two output terminals of the output switching switch 20 is connected to the output of the capacitor 15, and the other output terminal is connected to the output of the capacitor 19. Then, the output switching switch 20 selects the terminal voltage of the capacitor 15 and the terminal voltage of the capacitor 19, and applies them to the positive electrode 2 of the electrode 1. The other end of each capacitor 13, 15, 17, 19, and the negative electrode 3 of electrode 1 are Each is connected to the negative terminal of the power supply 11.

Here, the magnetic switches 16 and 18 are capable of magnetically switching the current, and are usually in an unsaturated state while the current value flowing through the magnetic switches 16 and 18 is small. Evening is getting very big. Also, when the value of the current flowing through the magnetic switches 16 and 18 becomes larger than a predetermined value, it becomes saturated and the inductance becomes very small.

According to the pulse generator 10 having such a configuration, a pulse voltage waveform having a short rise time can be obtained as follows.

First, the power supply 11 accumulates electric charge at a predetermined voltage in the capacitor 13 via the resistor 12 during a predetermined time (repetition cycle time). Next, the switch of the trigger switch circuit 14 switches to ΔN, and the electric charge stored in the capacitor 13 is transferred to the capacitor 15 via the trigger switch circuit 14. At this time, during the half cycle of the cycle time determined by the natural oscillation frequency of the LC oscillation circuit composed of the coil in the trigger switch circuit 14 and these capacitors 13 and 15, the transfer of the charge is Complete. Because the magnitude of the unsaturated inductance of the magnetic switch 16 is large, and during the above-mentioned half cycle, it is set to be larger than the inductance of the coil in the trigger switch circuit 14, so that the capacitor i3 Almost all the charge is transferred to the capacitor 15. When the charge transfer is completed, the terminal voltage of the capacitor 15 reaches the peak value. Thereafter, the value of the current flowing through the magnetic switch 16 increases and reaches a saturation state. Since the magnitude of the inductance of the magnetic switch 16 in the saturated state is set to be much smaller than the inductance of the coil in the trigger switch circuit 14, the charge of the capacitor 15 is generated in the next half cycle. Does not return to the capacitor 13 but goes to the capacitor 17 via the magnetic switch 16. At this time, the transfer of the charge is completed during a half cycle of the oscillation cycle time of the LC oscillation circuit constituted by the saturation inductance of the magnetic switch 16 and the capacitors 15 and 17. In this case, similarly, the magnitude of the unsaturated inductance of the magnetic switch 18 is large, and is larger than the saturation inductance of the magnetic switch 16 during the above half period. Therefore, almost all the charge of the capacitor 15 is transferred to the capacitor 17. When the charge transfer is completed, the terminal voltage of the capacitor 17 reaches the peak value.

Thereafter, in the same manner as above, the magnitude of the saturation inductance of the magnetic switch〗 8 is set to be much smaller than the saturation inductance of the magnetic switch 16. The charge does not return to the capacitor 15 but passes to the capacitor 19 via the magnetic switch 18. At this time, the transfer of the electric charge is completed during a half cycle of the oscillation cycle time of the LC oscillation circuit constituted by the saturation inductance of the magnetic switch 18 and the capacitors 17 and 19. Assuming that the capacitors 13, 15, 17, and 19 are equal in size, the half cycle time when the charge of the capacitor 13 sequentially transfers to the next stage capacitors 15, 17, and 19 is Go short. Therefore, the rise time of the voltage when the charge is stored in the capacitor 19 is shorter than the rise time of the voltage when the charge is stored in the capacitor 15. FIGS. 5 and 6 show the voltage waveforms of the capacitors 15 and 19 at this time. In this way, the rise of the pulse voltage can be made faster by the Panorless compression circuit.

Then, the output switching switch 20 switches between the voltage of the capacitor 15 and the voltage of the capacitor 19 to select the rise time of the pulse voltage applied to the electrode 1. Further, by switching the rise time of the pulse voltage, it is possible to select whether to discharge in the solution 9 or in the rock for the following reasons. This means that the same electrode 1 can be used to dig a preliminary hole 4 or to perform the main crushing, as in the first embodiment. Figure 7 shows the general relationship between the rise time of the applied pulse voltage and the dielectric strength of each insulator when this pulse voltage is applied. Here, the horizontal axis represents the rise time of the applied pulse voltage (generally, the time required for the pulse voltage to rise from 10% to 90% of the maximum value), the vertical axis represents the withstand voltage, and It is expressed in semilogarithms with the logarithmic scale on the horizontal axis. In the figure, curves 41, 42, and 43 represent water, marble, Represents the characteristics of sandstone. As can be seen from the figure, when, for example, water is used as the solution 9, the withstand voltage of rock such as marble or sandstone is smaller than that of water when the rise time of the pulse voltage is short. Therefore, at this time, the discharge current flows more easily in the rock than in the solution (water), so that it is suitable for drilling the preliminary hole 4 in the rock or crushing the rock deeply. Further, in the above, when the rise time of the pulse voltage is long, rocks such as marble and sandstone have a higher withstand voltage than water. Therefore, in this case, the discharge current flows more easily in the solution (water) than in the rock, and is suitable for crushing over a wide area by the shock wave of the solution.

As described above, even when the same solution 9 is used, the rise time of the applied pulse voltage, the withstand voltage of the component such as the rock to be crushed with respect to this rise time, and the withstand voltage of the solution 9 From the relationship, the path of the discharge current can be selected by changing the rise time of the applied pulse voltage. This is the reason why the present invention makes it possible to select between discharging in solution 9 and discharging in rock.

In this embodiment, a single pulse generator 10 is provided with several circuits capable of generating pulse waveforms having different rise times, and by switching this output circuit, a high-voltage pulse is generated. This shows an example in which the rise time is changed. However, the configuration is not limited to this.For example, separate pulse generators for generating pulse waveforms having different rise times are separately provided, and the output voltage is switched between when drilling a preliminary hole and when crushing. You may do so. At this time, the electrodes may be different for preliminary drilling and crushing, or the same electrode may be used in common.

Next, a third embodiment will be described with reference to FIGS. In the present embodiment, the input energy is increased by changing the pulse voltage waveform.

Each of the power supplies 21 and 31 is a DC power supply that outputs predetermined voltages VI and V 2 as shown in FIG. Here, the predetermined voltages VI and V2 are expressed by the following equations. VI <V2

In order to satisfy the condition, for example, it is set to V I-30 K V. The output of the power supply 21 is applied to the capacitor 23 via the resistor 22, and the output voltage of the capacitor 23 is applied to the capacitor 25 via the trigger switch circuit 24. The output voltage of the capacitor 25 is applied to the positive electrode 2 of the electrode 1 via the coil 26. The output of the power supply 31 is applied to the capacitor 33 via the resistor 32, and the output voltage of the capacitor 33 is applied to the capacitor 35 via the trigger switch circuit 34. Then, the output voltage of the capacitor 35 is also applied to the positive electrode 2. The capacitance of each of the capacitors 23 and 25 is larger than that of each of the capacitors 33 and 35. As in the second embodiment, each of the trigger switch circuits 24 and 34 is provided with a series circuit including, for example, a switch composed of a thyratron and the like and a coil having a predetermined inductance.

FIG. 9 shows an output voltage waveform from the pulse generator 10 having the above configuration, and the operation in the present embodiment will be described with reference to FIG.

When the voltage V I is output from the power supply 21, the terminal voltage of the capacitor 23 becomes substantially equal to V I after a predetermined time, and a predetermined amount of charge is accumulated in the capacitor 23. When the voltage V2 is output from the power supply 31, the terminal voltage of the capacitor 33 becomes substantially equal to V2 after a predetermined time, and a predetermined amount of electric charge is accumulated in the capacitor 33. Then, when the switch of the trigger switching circuit 24 is turned ON, the electric charge of the capacitor 23 is transferred to the capacitor 25, and the terminal voltage of the capacitor 25 reaches approximately V I. At this time, since the inductance of the coil in the trigger switching circuit 24 is set to be smaller than the inductance of the coil 26, almost all charges of the capacitor 23 are reduced to the respective capacitors 23, 25. The operation shifts to the capacitor 25 with a natural oscillation cycle time determined by the capacitance of the coil and the inductance of the coil in the trigger switch circuit 24.

Next, when the terminal voltage of the capacitor 25 reaches approximately VI, when the switch of the trigger switch circuit 34 is turned on, the electric charge of the capacitor 33 is transferred to the capacitor 35. Then, the terminal voltage of the capacitor 35 becomes V 2. At this time, since the inductance of the coil in the trigger switch circuit 34 is set to be smaller than the inductance of the coil 26, almost all charges of the capacitor 33 transfer to the capacitor 35. . Since the capacitance of each of the capacitors 33, 35 is smaller than the capacitance of each of the capacitors 23, 25, assuming that the inductance of each of the coils in the trigger switch circuits 24, 34 is equal, the above-mentioned capacitor 35 The transfer time of the charge to the capacitor 25 is faster than the transfer time to the capacitor 25 described above. Therefore, the rising speed of the terminal voltage of the capacitor 35 is increased. As a result, a pulse voltage having a high peak voltage value (equal to V 2) and a short rise time is applied between the positive electrode 2 and the negative electrode 3, and dielectric breakdown is likely to occur.

As described above, after the discharge starts due to the charge of the capacitor 35, when the terminal voltage of the capacitor 35 starts to decrease, the charge of the capacitor 25 is passed through the coil 26 for a predetermined oscillation cycle time. It shifts to the capacitor 35. As a result, the electric charge of the capacitor 25 is slowly discharged from the electrode 1 more slowly than the discharge of the peak voltage pulse. Since the capacity of the capacitor 25 is larger than that of the capacitor 35, the amount of charge (energy) stored in the capacitor 25 is large, and therefore, the discharge energy input to the rock is increased. As a result, a wide range of rocks can be crushed, and efficient electrocrushing can be performed.

The method of using the electrode 1 at this time is shown in FIG. 10 and FIG. Here, an example is shown in which each of the positive electrode 2 and the negative electrode 3 of the electrode 1 has a rod shape. As shown in FIG. 10, the positive electrode 2 and the negative electrode 3 of the electrode 1 connected to the pulse generator 10 are inserted at a predetermined distance into one preliminary hole 4 filled with the solution 9. At this time, a shock wave is generated by discharging with the solution 9, and it is possible to crush a large amount in a large area around the preliminary hole 4. Alternatively, as shown in Fig. 11, the positive electrode 2 and the negative electrode 3 are separately inserted into at least two or more different preliminary holes 4 and 4, and the pulse generator 10 is connected between the positive electrode 2 and the negative electrode 3. You may. As a result, an electric current flows through a rock or the like between the positive electrode 2 and the negative electrode 3, and this crushing is performed. In this case, the pulse generation device described in the present embodiment is used. According to the device 10, after the insulation of rocks and the like is destroyed by high-voltage pulses with a fast rise, a large amount of energy is injected into the rocks in a slow discharge time. Therefore, it is possible to increase the breaking force of the electro-fracture.

Next, a fourth embodiment will be described based on FIG. 12 and FIG. In FIG. 12, the same components as those in FIG. 8 are denoted by the same reference numerals, and description thereof will be omitted. The output voltages V I and V 2 of each power supply 2 and 3 1 are calculated by

V] <V 2

Is set to satisfy. The output of the power supply 21 is applied to the capacitor 35 via the resistor 27, and the output voltage of the capacitor 3 is applied to the positive electrode 2 of the electrode 1. The output of the power supply 31 is applied to the capacitor 33 via the resistor 32, and the output voltage of the capacitor 33 is applied to the capacitor 35 via the trigger switching circuit 34.

FIG. 13 shows the output voltage waveform of the pulse generator 10 described above, and the operation of the present embodiment will be described with reference to FIG. When the voltage VI is output from the power supply 21, a current flows to the capacitor 35 via the resistor 27, and after a predetermined time, the terminal voltage of the capacitor 35 becomes substantially equal to VI, and a predetermined amount of electric charge is discharged. Stored in 3-5. At this time, the voltage between the positive electrode 2 and the negative electrode 3 has a low force voltage equal to the above-mentioned voltage VI, so that the discharge has not yet started. In addition, when the voltage V 2 is output from the power supply 31, the terminal voltage of the capacitor 33 becomes substantially equal to V 2 after a predetermined time, and a predetermined amount of charge is accumulated in the capacitor 33. Next, when the switch of the trigger switch circuit 34 is turned on, the electric charge of the capacitor 33 is transferred to the capacitor 35, and the terminal voltage of the capacitor 35 rises to V2. At this time, since the inductance of the coil in the trigger switch circuit 34 is set to be smaller than the resistance 27, almost all the electric charge of the capacitor 33 is transferred to the capacitor 35. Since the capacitance of each of the capacitors 33 and 35 is sufficiently small, the transfer time of the electric charge to the capacitor 35 is short. Therefore, the rising speed of the terminal voltage of the capacitor 35 is increased. As a result, the peak voltage between positive electrode 2 and negative electrode 3 is equal to V 2, When a short pulse voltage is applied, the insulation is destroyed and discharge starts.

As described above, when the terminal voltage of the capacitor 35 starts to decrease after the discharge is started by the charge of the capacitor 35, the charge is accumulated in the capacitor 35 from the power supply 21 via the resistor 27. Since the insulation between the positive electrode 2 and the negative electrode 3 is broken, the discharge continues even if the terminal voltage of the capacitor 35 becomes V I. As a result, the electric charge from the power supply 21 is discharged from the electrode 1 slowly and slowly from the discharge of the peak voltage pulse. This increases the discharge energy input to the rock. As a result, a wide range of rocks can be crushed, and efficient electrocrushing can be performed.

Next, an example in which a plurality of preliminary holes are excavated and crushed over a wide area according to the fifth embodiment will be described with reference to FIGS. 14 and 15. FIG.

First, a plurality of preliminary holes 4 are drilled as shown in FIG. At this time, the same electrode 1 may be used repeatedly for excavation, or at least two or more electrodes 1, 1 and a pulse generator IQ, 10 connected to each electrode 1, 1 may be used. It may be used to excavate at the same time.

Also, as shown in Fig. 15, separate crushing electrodes 1a and 1b are inserted into the two preliminary holes 4 and 4, respectively. At this time, switching switches 45 and 46 are provided between each of the crushing electrodes 1 a and 1 b and each of the pulse generators 10 a and 10 b, and one of them is switched by the switching switch 45. Between the negative electrode 3a of the first electrode 1a and the negative electrode of the pulse generator 10a, and the switching switch 46 disconnects the positive electrode 2b of the other electrode 1b and the positive electrode of the pulse generator 10b. It is possible. At the time of crushing, both switching switches 45 and 46 are turned off, and when either one of the pulse generators 10a outputs a high-voltage pulse, the positive electrode 2a of electrode 1a and the negative electrode of electrode 1b Discharge current flows between 3b. This allows a large amount of material to be crushed over a wide area because the discharge current flows through the rock between the preliminary holes. Industrial applicability

The present invention provides a method of crushing a substance by pulse electric energy discharge, which can efficiently perform pre-hole drilling and crushing at the time of electro crushing, and can efficiently perform electro crushing, a crushing apparatus thereof, a method of generating a high voltage pulse, And it is useful as a high voltage pulse generator thereof.

Claims

The scope of the claims

1. Insert the electrode into the preliminary hole (4) provided in the material to be fractured, fill the periphery of this electrode with the solution (9), apply a high voltage pulse to this electrode, and discharge the In the method for crushing a substance by pulsed electric energy discharge for crushing a substance, a discharge current is passed through the electrode for drilling a preliminary hole, and a preliminary hole (4) is opened in the substance. A method for crushing a substance by pulsed electric energy discharge, comprising: inserting the electrode and crushing the substance by flowing a discharge current through the crushing electrode.

2. The substance according to claim 1, wherein a discharge current flows through the substance when the preliminary hole is drilled, and a discharge current flows through the solution (9) during the crushing. Crushing method.

3. By changing the rising time of the high voltage pulse between the time of the preliminary hole excavation and the time of the crushing, it is possible to select whether the discharge current flows in the substance or the solution (9). A method for crushing a substance by pulsed electric energy discharge according to claim 1.

4. At the time of drilling the preliminary hole, the tip of the electrode is brought into contact with the substance to cause a discharge current to flow through the substance, and at the time of crushing, the tip of the electrode is separated from the substance and is placed in the solution (9) 2. A method for crushing a substance by pulsed electric energy discharge according to claim 1, wherein a discharge current is supplied to the electric field.

5. At least two or more electrodes are used for drilling the preliminary holes, and at least two or more preliminary holes (4) are drilled. At the time of crushing, the electrodes are respectively inserted into two or more different preliminary holes. And a high voltage between these different electrodes. The substance is broken by the pulsed electric energy discharge according to claim 1, wherein Crushing method.

6. An electrode inserted into the preliminary hole (4) opened in the material to be crushed, a solution (9) filling the periphery of the electrode, and a pulse generator (10) for applying a high-voltage pulse to this electrode An apparatus for crushing a substance by pulsed electrical energy discharge for crushing the substance by a discharge current at the electrode,

An apparatus for crushing a substance by pulse electric energy discharge, comprising: the electrode for preliminary hole drilling; and the electrode for crushing.

7. The pulse crushing material according to claim 6, further comprising a pulse generator (10) for digging and crushing the preliminary hole for outputting the high-voltage pulse having a different rise time. apparatus.

8. The pulse electric energy discharge according to claim 6, wherein the respective electrodes for pre-hole drilling and crushing and the pulse generator (10) are shared during the pre-hole drilling and crushing. Material crushing equipment.

9. At least two or more pre-drilling electrodes for simultaneously drilling at least two or more pre-holes (4), and inserted into these two or more different pre-holes (4) and the high voltage At least two or more crushing electrodes to which a pulse is applied, wherein a discharge current flows between the two or more electrodes inserted in the two or more different preliminary holes to crush the substance. The electric crushing equipment according to the item 6.

10. In a method of generating a high-voltage pulse of material crushing by pulse electric energy discharge in which a high-voltage pulse is applied to an electrode, and a discharge current at the electrode digs or crushes the material to be crushed, Energy is stored in at least two capacitors having different capacities on the tile at different terminal voltage values, and the energy of the capacitor stored on the high voltage side is transferred to the electrode at an early stage of discharge at the time of a material breakdown. And discharging the energy stored in the capacitor at a lower voltage than that of the capacitor.

1 1. A high-voltage pulse generator is used to apply a high-voltage pulse to an electrode and excavate or crush the material to be crushed by the discharge current at this electrode.

Two DC power supplies (21, 31) having different output voltage values, and a first capacitor (33, 35) for storing energy from the higher voltage power supply (31) of the two DC power supplies; Energy is stored from a lower voltage power supply (21), the second capacitor (23, 25) having a capacity larger than the capacity of the first capacitor, and stored in the first or second capacitor. A high-voltage pulse generator comprising at least two or more trigger switching circuits (24, 34) for discharging energy at said electrodes.

1 2. In a high voltage pulse generator for crushing material by pulse electric energy discharge, which applies a high voltage pulse to the electrode and excavates or crushes the material to be crushed by the discharge current at this electrode,

Two DC power supplies (21, 3) having different output voltage values; a means for directly discharging the energy of the lower voltage power supply (21) of the two DC power supplies from the electrode; A capacitor (33, 35) for storing energy from a voltage power supply (31), and a trigger switch (34) for discharging the energy stored in the capacitor at the electrode. Voltage pulse generator.