JPH10227193A - Electric crushing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute electric crushing work in an insulation medium without causing any bad influence by the insulation medium and to carry out electric crushing work efficiently while avoiding environmental problems accordingly. SOLUTION: After a crushing head 10 including an electrode 13 is tightly closed with a seal 16, a high pressure gas generating section 12 supplies gas to the crushing head 10 through a hose 14, and the crushing head is filled with high pressure gas. Under such high pressure gas conditions, voltage pulse is supplied to the electrode 13 from a high pressure pulse generating section 11, and a crush object 17 making high pressure gas as insulation medium is electrically crushed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric crushing method in which an insulating medium is supplied between an electrode and a crushed object, and the crushed object is broken down by discharge between the electrodes.
The present invention relates to an electric crushing method capable of performing electric crushing in an insulating medium without causing adverse effects of the insulating medium and thereby efficiently performing an electric crushing operation while avoiding environmental problems.

[0002]

2. Description of the Related Art Conventionally, it is necessary to crush rocks, concrete, and other insulating solids when excavating, demolition, crushed stones, and treating industrial waste. In such a case, a mechanical method of mechanically crushing this insulating solid,
A blasting method of crushing using explosives and a shock wave method of crushing using shock waves are often used.

However, this mechanical method has a problem that a crushing tool or a crushing device is easily worn out. The blasting method has problems of safety, noise and vibration, and the shock wave method requires setup. There is a problem that it takes time.

For this reason, recently, a technique of crushing a non-conductive solid such as rock or concrete by electric energy discharge in a liquid having a high dielectric breakdown voltage such as oil (hereinafter, referred to as a technique).
It is called "electro-crushing technology." ) Has appeared.

For example, Japanese Patent Application Laid-Open No. Hei 4-222794 discloses that a solid insulator such as a rock is drilled with a drill or the like.
A technique is disclosed in which a high-voltage pulse is supplied in a state in which a viscous electrolytic solution (for example, copper sulfate electrolytic solution) is placed in the hole, thereby performing electric crushing using electric energy of plasma discharge. .

That is, in the conventional electro-crushing technique, the solid is indirectly crushed through an insulating medium such as an electrolyte or oil having a higher breakdown voltage than a non-conductive solid. I have.

[0007]

However, if the rock or concrete is crushed in a liquid such as oil using the above-mentioned prior art, the crushed material such as concrete shards is covered with oil. Significant efficiency and environmental issues arise.

[0008] That is, the electro-crushed oil-smeared fragments significantly impede the progress of the subsequent work, so that it is necessary to leave such fragments in some way.

Concretely, it is possible to purify the oil adhering to the fragments or to discharge the fragments themselves out of the work area. In any case, a secondary operation after the electro-crushing is required, and the efficiency is increased. Not a target.

Further, when a large amount of non-conductive solids (hereinafter referred to as “objects to be crushed”) to be subjected to electro-crushing exist, for example, when excavating rocks, not only oil itself but also oil itself is used. Since the cost of transporting and storing oil is also high, the cost of the electro-crushing operation is limited.

Further, the oil adhering to such fragments is
At present, the situation where electrocrushing can be performed is limited because it has a significant impact on the environment.

As described above, when performing electro-crushing in a liquid such as oil, the adverse effects of the liquid are removed.
How to improve the negative effects on work efficiency and the environment is an important issue.

Therefore, the present invention solves the above problems,
An object of the present invention is to provide an electric crushing method capable of performing electric crushing in an insulating medium without causing an adverse effect of the insulating medium and thereby efficiently performing an electric crushing operation while avoiding environmental problems.

[0014]

In order to achieve the above object, a first aspect of the present invention provides an insulating medium between an electrode and an object to be crushed, and the object to be crushed by discharge between the electrodes. In the electro-crushing method of electro-crushing, the surroundings of the electrode and the object to be crushed are filled with a high-pressure gas, and the object to be crushed is electro-crushed using the high-pressure gas as an insulating medium. The effect is obtained.

1) The time required to reach the cross point between the dielectric breakdown curve of the insulating medium and the dielectric breakdown curve of the object to be crushed is delayed, so that a margin for the rise time of the voltage pulse can be obtained.

2) Efficient electrocrushing can be achieved by eliminating adverse effects on the environment and secondary operations as in the case of using insulating oil.

According to a second aspect of the present invention, there is provided an electrocrushing method for supplying an insulating medium between an electrode and an object to be crushed and electrically crushing the object to be crushed by discharge between the electrodes. Since the periphery of the object is maintained in a high vacuum state, and the high vacuum state is used as an insulating medium to electro-crush the object to be crushed, it is not necessary to prepare an insulating medium in advance. .

According to a third aspect of the present invention, there is provided an electrocrushing method for supplying an insulating medium between an electrode and an object to be crushed and electrically crushing the object to be crushed by discharge between the electrodes. Since the periphery of the object is filled with ice and the crushed object is electro-crushed using the ice as an insulating medium, the electro-crush can be efficiently performed using ice which can be obtained more easily.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

First, the concept of the first embodiment in which a high-pressure gas body is used as an insulating medium will be described.
Here, a case where rock is used as the object to be crushed is shown.

FIG. 2 is a diagram showing the relationship between the breakdown voltage, time, and the like for rock, insulating oil, and air.

As shown in FIG. 1A, rock, insulating oil, normal atmospheric pressure air (hereinafter referred to as "atmospheric pressure air") and high pressure air (hereinafter referred to as "high pressure air"). ) Has the property that it decreases with the voltage rise time.

That is, when dielectric breakdown of rock, insulating oil, atmospheric pressure air and high pressure air, the earlier the voltage rise time, the higher the dielectric breakdown voltage required for the dielectric crushing,
Conversely, the longer the voltage rise time, the lower the breakdown voltage.

Here, first, looking at the relationship between the dielectric breakdown curve of the conventionally used insulating oil and the dielectric breakdown curve of the rock which is the object to be crushed, the two curves are located at predetermined positions (hereinafter referred to as "cross points"). .) Pr.

That is, the cross point Pr means that when a voltage higher than the dielectric breakdown voltage v is applied for a predetermined time during the voltage rise time tr, both the insulating oil and the rock are electro-crushed.

The time t corresponding to the cross point Pr
Considering the time tr 'prior to r, the breakdown voltage v
Since the dielectric breakdown voltage v2 of the insulating oil is higher than that of 1, only the rock can be electrocrushed by applying a dielectric breakdown voltage of v1 or more and less than v2.

Next, looking at the relationship between the dielectric breakdown curve of the atmospheric pressure air and the dielectric breakdown curve of the insulating oil, the dielectric breakdown voltage of the atmospheric pressure air is relatively lower than the dielectric breakdown voltage of the insulating oil. The time tn corresponding to the cross point Pn of both the breakdown curves becomes considerably shorter than the time tr.

Therefore, in order to use such atmospheric air as an insulating medium, it is necessary to supply an applied voltage which rises at least more steeply than the time tn corresponding to the cross point Pn.

However, since it is actually difficult to supply an applied voltage that rises earlier than the time tn, conventionally, an insulating oil is used as the insulating medium instead of the atmospheric pressure air.

On the other hand, looking at the relationship between the dielectric breakdown curve of the high-pressure air and the dielectric breakdown curve of the insulating oil used in the present embodiment as the insulating medium, the breakdown voltage of the high-pressure air is higher than that of the insulating oil. Since the voltage is relatively higher than the dielectric breakdown voltage of the oil, the time tc corresponding to the cross point Pc of both the dielectric breakdown curves is longer than the time tr.

For this reason, the breakdown voltage can be applied with more time than the insulating oil conventionally used as an insulating medium, so that the rock to be crushed can be efficiently crushed.

As described above, considering the supply of the applied voltage,
The use of high-pressure air rather than the use of insulating oil allows the object to be crushed to be electro-crushed more efficiently. In this embodiment, a high-pressure gas represented by high-pressure air is used as the insulating medium. doing.

By using the high-pressure gas employed in the present embodiment, it is also possible to eliminate the adverse effects of a liquid such as oil on the electro-crushing operation and the adverse effects on the environment as in the conventional electro-crushing technique. it can.

FIG. 4B is a diagram showing the correspondence between the breakdown voltage of air, sulfur hexafluoride gas (SF6 gas) and insulating oil and the gap length. As shown in FIG.
Atmospheric pressure (1 atm) air and SF6 gas have lower breakdown voltage than insulating oil, but the breakdown voltage of air and SF6 gas increases as the pressure increases, and 2
In the case of 7.2 atm air and 6.8 atm SF6 gas, the breakdown voltage is much higher than that of insulating oil.

Therefore, it is understood that not only air but also high-pressure gas such as SF6 gas can be used as the insulating medium.

The basic concept of the first embodiment has been described.

Next, the configuration of the electro-crushing apparatus used in the first embodiment will be described.

FIG. 1 is a diagram showing a configuration of an electro-crushing apparatus used in the present embodiment.

The electro-crushing apparatus shown in FIG. 1 employs a high-pressure gas such as high-pressure air or high-pressure SF6 as an insulating medium, and reaches a cross point between a breakdown curve of the high-pressure gas and a breakdown curve of an object to be crushed. By supplying a voltage pulse that rises in a shorter time than the time, the object to be crushed is electro-crushed.

As shown in FIG.
A crushing head 10 filled with a high-pressure gas, a high-pressure pulse generator 11 that supplies a voltage pulse that rises in a shorter time than a time when the breakdown point of the high-pressure gas and the breakdown curve of the object 17 to be broken are reached, A high-pressure gas generator 12 for supplying a high-pressure gas to the crushing head 10;
7, a hose 14 connecting the crushing head 14 and the high-pressure gas generator 12, and a release valve 1 for releasing the high-pressure gas filled in the crushing head after the electro-crushing.
5 and a seal 16 for preventing leakage of high-pressure gas.

When the crushing object 17 is to be electro-crushed, the electrode 13 is brought into contact with the crushing object 17, the periphery of the crushing head 10 is sealed with a seal 16, and then the high-pressure gas is supplied from the high-pressure gas generator 12. Supply.

Thereafter, the high-pressure pulse generator 11 supplies the electrode 13 with a voltage pulse that rises earlier than the cross point between the insulation breakdown curve corresponding to the high-pressure gas in the crushing head 10 and the insulation crushing curve of the object 17 to be crushed. .

Thus, the object to be crushed is crushed earlier than the high-pressure gas in the crushing head 10. After the desired area of the crushing target 17 is electro-crushed, the release valve 15 is opened to release the high-pressure gas.

As described above, in this electric crushing apparatus, a high pressure gas which does not have such a problem is used as an insulating medium instead of the insulating oil which has a problem on the environment and the like. Electro crushing.

Next, a specific example in the case where the electric crusher shown in FIG. 1 is applied to an excavator will be described.

FIG. 3 is a view showing the appearance of an excavator to which the electric crusher shown in FIG. 1 is applied.

As shown in the side view of FIG. 3 (a) and the front view of FIG. 3 (b), this excavator has a lower traveling body 31 which can travel freely. An upper swing body 32 is freely provided.

A pulse generator capable of generating pulse electricity reaching the breakdown voltage of the object to be crushed at least earlier than the crossing point, and a high-pressure gas supplied to the crushing head 10 are provided above the upper rotating body 32. And a high-pressure gas generating section.

Further, a crushing head 10 is provided at the tip of an arm 33 extending from the upper revolving unit 32, and the crushing head 10 is used to perform electro-crushing of an object to be crushed. Therefore, along the arm 33, a power line for supplying a pulse voltage and a hose for supplying a high-pressure gas are provided.

When the excavation work is performed, the arm 3
After the crushing head 10 is brought into close contact with the desired surface of the object to be crushed by operating 3, the high-pressure gas generator supplies high-pressure gas to the crushing head 10, and when the crushing head 10 reaches a predetermined pressure, The voltage pulse generated by the pulse generator is supplied to the electrodes in the crushing head 10 to perform electro-crushing.

Next, the crushing head 10 will be specifically described.

FIG. 4 is a view showing the structure of the crushing head 10 shown in FIG.

As shown in FIG. 4, the crushing head 10
Is compressed by the arm 33 so that the electrode 13 is in contact with the object to be crushed, and after sealing the periphery of the electrode 13 with the seal 16, the high pressure gas generated by the high pressure gas
Feed via 4.

Then, when the inside of the crushing head 10 is brought into a high pressure state having a predetermined pressure, a voltage pulse generated by a pulse generator is applied to the electrode 13 to perform the electric crushing of the crushing object.

Thereafter, since the crushed fragments that have been electro-crushed accumulate inside the crushing head 10, the release valve 15 is released to reduce the pressure inside the crushing head 10, and then the flap 42 is opened via the operation of the cylinder 41. To expel the crushed fragments.

As described above, in the first embodiment, the high-pressure gas is used as the insulating medium, and the object to be crushed is electro-crushed in the high-pressure gas. Therefore, the following effects are obtained. Can be

1) Electric crushing can be performed efficiently while eliminating adverse effects on the environment caused by the insulating oil.

2) It is possible to delay the time required to reach the cross point between the dielectric breakdown curve of the insulating medium and the dielectric breakdown curve of the object to be crushed, thereby increasing the margin of the rise time of the voltage pulse.

In this embodiment, high-pressure air and S
Although F6 is employed as the insulating medium, a high-pressure gas obtained by compressing another gas may be employed as the insulating medium.

The first embodiment has been described above.

Next, a second embodiment in which a high vacuum state is used as an insulating medium will be described.

FIG. 5 is a diagram showing the configuration of the electro-crushing apparatus used in the second embodiment.

As shown in FIG.
The configuration is substantially the same as that of the electro-crushing apparatus shown in FIG. 1, and has a configuration in which a vacuum generator 51 is provided instead of the high-pressure gas generator 12.

The vacuum generating section 51 is a device for sucking air inside the head from the crushing head 50 to bring the inside of the crushing head 50 into a high vacuum state. That is, in this electric crushing device, the object 17 to be crushed is subjected to electric crushing by using a high vacuum state as an insulating medium.

The configuration is the same as that of the electro-crushing apparatus shown in FIG. 1 except that a high vacuum state is used as an insulating medium by using the vacuum generating section 51. Therefore, detailed description thereof is omitted here. .

Next, in the electric crusher shown in FIG.
The reason why the high vacuum state can be adopted as the insulating medium will be described.

FIG. 6 is a diagram showing the relationship between the breakdown voltage, time, and the like for rock, insulating oil, and high vacuum.

As shown in FIG. 7A, the relationship between the high vacuum insulation breakdown curve employed as the insulating medium in the present embodiment and the insulation oil breakdown curve of the insulating oil is shown. Since the breakdown voltage is relatively higher than the breakdown voltage of the insulating oil, the time tb corresponding to the cross point Pb of the breakdown curve of the high vacuum and the rock is determined by the cross point Pr of the breakdown curve of the insulating oil and the rock. Is longer than the time tr corresponding to.

For this reason, by using the high vacuum as an insulating medium, a breakdown voltage is applied with more time than in the case of using an insulating oil, whereby the rock to be crushed is efficiently electrocrushed. can do.

As described above, considering the supply of the applied voltage,
The use of a high vacuum rather than the use of insulating oil allows the object to be crushed to be efficiently crushed and the adverse effects of the insulating oil to be removed. It is used as a sexual medium.

FIG. 11B is a diagram showing the correspondence between the breakdown voltage of high vacuum and insulating oil and the gap length.
As shown in the figure, regardless of the gap length, the high vacuum has a relatively higher breakdown voltage than the insulating oil.

Therefore, it can be seen that this high vacuum can be used as an insulating medium regardless of the gap length.

Next, a specific example in which the electric crusher shown in FIG. 5 is applied to an excavator will be described. However, since the entire configuration of the excavator can be the same as that shown in FIG. 3, only the crushing head will be described here.

FIG. 7 is a diagram showing the configuration of the crushing head 10 when the electric crushing device shown in FIG. 5 is applied to an excavator.

As shown in the figure, the crushing head is pressed by an arm so that the electrode 13 is in contact with the object to be crushed, and the periphery of the electrode 13 is sealed with a seal 16. The inside of the crushing head is evacuated by sucking air. In addition, when performing this electric crushing, the open / close pinch valve 70 is closed.

Then, when the inside of the crushing head is brought into a predetermined vacuum state, a voltage pulse generated by the pulse generator is applied to the electrode 13 to perform the electric crushing of the crushing object.

Thereafter, since the crushed fragments that have been electro-crushed accumulate inside the crushing head, the open / close pinch valve 70 is opened to bring the inside of the crushing head to atmospheric pressure, and then the crushed fragments are sucked by the suction device.

As described above, in the second embodiment, a high vacuum is adopted as the insulating medium, and the object to be crushed is electro-crushed in the high vacuum, so that the following effects are obtained. Can be

1) The adverse effect on the environment caused by the insulating oil can be eliminated.

2) The time required to reach the cross point between the dielectric breakdown curve of the insulating medium and the dielectric breakdown curve of the object to be crushed is delayed, so that a margin for the rise time of the voltage pulse can be obtained.

3) It is not necessary to prepare an insulating medium in advance, so that the electric crushing can be performed efficiently.

The second embodiment has been described.

Next, a third method using ice as an insulating medium is described.
An embodiment will be described.

FIG. 8 is a diagram showing a configuration of an electro-crushing apparatus used in the third embodiment.

As shown in FIG.
The configuration is the same as that of the electric crushing apparatus shown in FIG.

The ice supply unit 81 is a device for supplying ice for bringing the crushing head 80 into a frozen state, and more specifically, supplies finely crushed ice to the inside of the crushing head 80. That is, in this electric crushing apparatus, the object 17 to be crushed is electrically crushed using ice as an insulating medium.

The melting section 82 is provided with the crushing head 8 after electro-crushing.
0 is a device that supplies a heat source for melting ice inside. In this embodiment, since the crushed ice is supplied into the crushing head 80, the melting portion 82 is used only when the crushed ice is solidified.

Except for the supply and melting of ice using the ice supply unit 81 and the melting unit 82, the configuration is the same as that of the electro-crushing apparatus shown in FIG. 1, and a detailed description thereof will be omitted here. .

Next, in the electric crusher shown in FIG.
The reason why ice can be used as the insulating medium will be described.

FIG. 9 is a diagram showing the relationship between the dielectric breakdown voltage, time, and the like for rock, insulating oil, and ice.

As shown in FIG. 9A, the relationship between the dielectric breakdown curve of ice used as an insulating medium in this embodiment and the dielectric breakdown curve of insulating oil shows that the dielectric breakdown voltage of the ice. Is higher than the breakdown voltage of the insulating oil, the time ti corresponding to the cross point Pi of the breakdown curve of ice and rock corresponds to the cross point Pr of the breakdown curve of insulation oil and rock. It becomes longer than the time tr.

Therefore, by using this ice as an insulating medium, it is possible to apply a breakdown voltage with more time than in the case of using insulating oil, and thereby to efficiently crush rocks, which are objects to be crushed, become.

As described above, considering the supply of the applied voltage,
The use of ice rather than the use of insulating oil can efficiently crush the object to be crushed and remove the adverse effects of the insulating oil. Has been adopted as.

FIG. 9B is a diagram showing the correspondence between the breakdown voltage of ice and insulating oil and the number of times of breakdown. As shown in FIG. Than the dielectric breakdown voltage. Therefore, it can be seen that such ice can be used as an insulating medium.

Although the case where benzene is used as the insulating oil is shown here, when another insulating oil such as petroleum ether or n-hexane is used, the dielectric breakdown voltage is almost the same as that of benzene.

Next, a specific example in which the electric crusher shown in FIG. 8 is applied to an excavator will be described. However, since the entire configuration of the excavator can be the same as that shown in FIG. 3, only the crushing head will be described here.

FIG. 10 is a diagram showing a configuration of a crushing head when the electric crushing device shown in FIG. 8 is applied to an excavator.

As shown in the figure, the crushing head is pressed by an arm so that the electrode 13 is in contact with the object to be crushed, and the periphery of the electrode 13 is sealed with a seal. To make the inside of the crushing head iced.

Then, when the inside of the crushing head becomes iced, a voltage pulse generated by the pulse generator is applied to the electrode 13 to perform the electric crushing of the crushing target.

Thereafter, crushed fragments accumulate inside the crushing head due to the electric crushing.
The crushed fragments remaining in the crushing head 1 are opened and the crushed fragments are discharged out of the crushing head together with the crushed ice. The crushing head is provided with a heat insulating material 100 in order to prevent the ice from melting at an early stage.

As described above, in the third embodiment, ice is used as the insulating medium, and the object to be crushed is electro-crushed in the crushing head iced.
The following effects can be obtained.

1) The adverse effect on the environment caused by the insulating oil can be eliminated.

2) The time required to reach the cross point between the dielectric breakdown curve of the insulating medium and the dielectric breakdown curve of the object to be crushed is delayed, so that a margin for the rise time of the voltage pulse can be obtained.

In the third embodiment, the crushed ice is supplied to the crushing head to perform the electric crushing of the object to be crushed in the crushing head with icing. However, the present invention is not limited to this. Instead, the present invention can be applied to a case where water is supplied and then cooled to be frozen, or a case where a mixture of water and ice is supplied into a crushing head.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an electro-crushing apparatus used in a first embodiment.

FIG. 2 is a diagram illustrating a relationship between a breakdown voltage, time, and the like regarding rock, insulating oil, and air.

FIG. 3 is a diagram showing an external appearance of an excavator to which the electric crusher shown in FIG. 1 is applied.

FIG. 4 is a diagram showing a configuration of a crushing head shown in FIG.

FIG. 5 is a diagram showing a configuration of an electro-crushing apparatus used in a second embodiment.

FIG. 6 is a diagram showing a relationship between a breakdown voltage, time, and the like regarding rock, insulating oil, and high vacuum.

FIG. 7 is a diagram showing a configuration of a crushing head when the electric crushing device shown in FIG. 5 is applied to an excavator.

FIG. 8 is a diagram showing a configuration of an electro-crushing apparatus used in a third embodiment.

FIG. 9 is a diagram showing a relationship between a breakdown voltage, time, and the like regarding rock, insulating oil, and ice.

FIG. 10 is a diagram showing a configuration of a crushing head when the electric crushing device shown in FIG. 8 is applied to an excavator.

[Explanation of symbols]

10: crushing head, 11: high-pressure pulse generator, 12
... high-pressure gas generator, 13 ... electrode, 14 ... hose, 1
5: release valve, 16: seal, 17: object to be crushed, 31
... lower traveling structure, 32 ... upper revolving structure, 33 ... arm,
41: cylinder, 42: flap, 50: crushing head, 51: vacuum generating part, 70: pinch valve for opening and closing, 8
0: crushing head, 81: ice supply unit, 82: melting unit,
100: heat insulating agent, 101: screw conveyor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takao Ino 1200 Manda, Manda, Hiratsuka, Kanagawa Prefecture Inside Komatsu Seisakusho Laboratories (72) Inventor Masayoshi Shiota 1200, Manda, Hiratsuka City, Kanagawa Prefecture Inside Komatsu Seisakusho Laboratories

Claims (3)

[Claims] 1. An electro-crushing method for supplying an insulating medium between an electrode and an object to be crushed and electrically crushing the object to be crushed by discharge between the electrodes, comprising: An electric crushing method comprising: filling the gas with a gas; and electrocrushing the object to be crushed using the high-pressure gas as an insulating medium. 2. An electrocrushing method for supplying an insulating medium between an electrode and an object to be crushed and electrically crushing the object to be crushed by electric discharge between the electrodes, wherein a height around the electrode and the object to be crushed is increased. An electric crushing method, wherein the object to be crushed is electrically crushed while maintaining a vacuum state and using the high vacuum state as an insulating medium. 3. An electrocrushing method for supplying an insulating medium between an electrode and an object to be crushed and electrically crushing the object to be crushed by discharge between the electrodes, wherein an ice is provided around the electrode and the object to be crushed. And electrically crushing the object to be crushed using the ice as an insulating medium.