DISCHARGE IMPACT BREAKING DEVICE

Abstract: An apparatus which is constituted to supply electrical energy to a melting and vaporizing material (for example metal wire 6) so as to cause the melting and vaporizing material to melt and vaporize, thereby demolishing an object to be demolished (such as concrete 2) using the vaporization and expansion force generated at the time of melting and vaporization of the material; wherein either by providing a granular material 8 which ejects from a container following the generation of the vaporization and expansion force, or by using an inflammable material as demolishing material 46 in which the melting and vaporizing material is immersed, a to-be-demolished object is demolished with a strong demolishing force.

Description: FIELD OF THE INVENTION The present invention relates to a demolishing apparatus using discharge impulse for demolishing an object to be demolished, such as concrete or rock mass, by using discharge energy, of the kind defined in the preamble of claim 1. BACKGROUND ART So far, dynamite has been known as demolishing means for demolishing an object to be demolished such as concrete or rock mass, however, a danger is involved in handling the dynamite. A demolishing apparatus of the kind defined in the preamble of claim 1, using discharge impulse, which uses discharge energy, has been proposed in recent years as a way of eliminating such danger. Such a demolishing apparatus using discharge impulse, previously known from JP-A-7 233 693, comprises a pair of electrodes connected to each other by means of a metal wire, and an energy supply circuit being connected to these electrodes and adapted to supply electrical energy to the metal wire, wherein the metal wire is immersed in a demolishing material (a liquid such as water or a semisolid material is used) filled in a demolishing container (hereinafter referred to simply as "container"). In this apparatus the predetermined electric energy is supplied to electrodes in such manner that a relation between e.g. maximum current value, supply time, and cross-sectional area of metal wire satisfies the predetermined formula. Next, the demolishing method for the aforementioned demolishing apparatus using discharge impulse will be explained. According to the method, the metal wire is immersed in the container filled with a demolishing material, the demolishing container is installed in an installation hole formed in an object to be demolished, the supply circuit is connected to the electrodes, a capacitor installed in this supply circuit is charged with a prescribed quantity of electrical energy, and this electrical energy is supplied to the metal wire for a short time (for example, several dozen µs), that is in other words, electric power is discharged. Whereupon, the metal wire suddenly melts and vaporizes and expands in volume. Following this, the demolishing material also suddenly vaporizes and expands. The volume expansion force of the metal wire is transmitted by this demolishing material, and the sudden volume expansion force of the metal wire and the vaporization and expansion force of the demolishing material act on the walls of the installation hole, for example, in such a manner that the installation hole is pressed outward, thereby demolishing the object to be demolished. However, with the aforementioned demolishing apparatus, the vaporization and expansion force of the demolishing material filled in the container is used to demolish an object to be demolished, so that resultant physical force such as a shock force cannot be sufficient. Therefore, there are such cases, depending on the kind of object to be demolished, that sufficient demolishing force cannot be obtained, and because of this, further improvement of the demolishing force is desired. It is an object of the present invention to provide a demolishing apparatus using discharge impulse which is capable of resolving the foregoing problems. DISCLOSURE OF THE INVENTION The present invention achieves the aforementioned object by virtue of a demolishing apparatus having the features defined in claim 1. Preferably metal balls, pebbles, ceramic balls or the like are used as the granular material. When using the apparatus, the melting and vaporizing material melts and vaporizes as the electrical energy is supplied to the melting and vaporizing material; the demolishing material vaporizes and expands following the melting and vaporizing of the melting and vaporizing material; the volume expansion force of the melting and vaporizing material is transmitted to the object to be demolished; and the volume expansion force generated during the melting and vaporization of the melting and vaporizing material causes the granular material to give a shock to the object to be demolished, thereby demolishing the object without fail. Also, in a preferred embodiment of the demolishing apparatus an insulating material such as a synthetic resin or paper, or a metal pipe, is used as a material constituting the container; and wherein a cylindrical holding body made of a hard material and having an opening at least at one end thereof is provided in the container such that the container faces the object to be demolished. According to this embodiment the melting and vaporizing material melts and vaporizes as the electrical energy is supplied to the melting and vaporizing material; the demolishing material vaporizes and expands following the melting and vaporizing of the melting and vaporizing material; the volume expansion force of the melting and vaporizing material is transmitted to the object to be demolished; and the granular material is ejected from the opening at one end of the cylindrical holding body toward the object to be demolished by the volume expansion force generated during the melting and vaporization of the melting and vaporizing material, thereby demolishing the object to be demolished reliably with the strong demolishing force. Also, in the demolishing apparatus according to a preferred embodiment the container is cylindrical and made of a hard material and includes a soft stopper element provided at an opening at one end of the cylindrical container. According to this embodiment, the melting and vaporizing material melts and vaporizes as the electrical energy is supplied to the melting and vaporizing material; the demolishing material vaporizes and expands following the melting and vaporizing of the melting and vaporizing material; the volume expansion force of the melting and vaporizing material is transmitted to the object to be demolished; and the granular material is caused to break the stopper element from the opening at one end of the cylindrical holding body so as to be ejected toward the object to be demolished, by the volume expansion force generated during the melting and vaporization of the melting and vaporizing material, thereby demolishing the object to be demolished reliably with the strong demolishing force. Also, in the demolishing apparatus according to a preferred embodiment said container is cylindrical and made of a hard material; a soft stopper element for holding the demolishing material and granular material is provided at a portion partway toward an opening formed at one end of the cylindrical container; and a space portion is formed between the stopper element and the one end of the cylindrical container. According to this embodiment the melting and vaporizing material melts and vaporizes as the electrical energy is supplied to the melting and vaporizing material; the demolishing material vaporizes and expands following the melting and vaporizing of the melting and vaporizing material; the volume expansion force of the melting and vaporizing material is transmitted to the object to be demolished; and the granular material is caused to break the stopper element to eject itself from the opening at one end of the cylindrical holding body toward the object to be demolished, by the volume expansion force generated during the melting and vaporization of the melting and vaporizing material, thereby demolishing the object to be demolished reliably with the strong demolishing force. Also, in the demolishing apparatus according to a preferred embodiment a portion of the cylindrical container corresponding to the space portion formed between the stopper element and the one end is formed in a conical shape such that the inner diameter of the portion on the opening side is greater than the inner diameter on the stopper element side. According to this embodiment, the melting and vaporizing material melts and vaporizes as the electrical energy is supplied to the melting and vaporizing material; the demolishing material vaporizes and expands following the melting and vaporizing of the melting and vaporizing material; the volume expansion force of the melting and vaporizing material is transmitted to the object to be demolished; and the granular material destroys the stopper element and is ejected, but in a limited ejection range, from the opening at one end of the cylindrical holding body toward the object to be demolished, by the volume expansion force generated during the melting and vaporizing of the melting and vaporizing material, thereby demolishing the object to be demolished reliably by the strong demolishing force. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross section showing the installed state of a demolishing apparatus using discharge impulse in an object to be demolished according to the first embodiment of the present invention; Fig. 2 is a cross section showing the installed state of a demolishing apparatus using discharge impulse in an object to be demolished according to the second embodiment of the present invention; Fig. 3 is a cross section showing the installed state of a demolishing apparatus using discharge impulse in an object to be demolished according to the third embodiment of the present invention; Fig. 4 is a cross section showing the installed state of a demolishing apparatus using discharge impulse in an object to be demolished according to the fourth embodiment of the present invention; Fig. 5 is a cross section showing the constitution of a demolishing apparatus using discharge impulse according to the fifth embodiment of the present invention; Fig. 6 is a cross section showing the installed state of the demolishing apparatus using discharge impulse in an object to be demolished according to the fifth embodiment of the present invention; DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is explained in more detail with reference to the appended figures. The first embodiment for implementing the present invention is explained on the basis of Fig. 1. A demolishing apparatus using discharge impulse 1 in this first embodiment comprises: a bottomed cylindrical or pouch-shaped demolishing container (hereinafter, simply referred to as "container") 4 inserted in an installation hole 3 formed in an object to be demolished 2; a pair of electrodes (or conductive wires) 5 inserted in this container 4; a metal wire (an example as a melting and vaporizing material, such as copper, iron or aluminum) 6 connecting the end portions of these electrodes (or conductive wires) 5; a demolishing material 7 and a granular material 8 filled in this container 4; and an electrical energy supplying device (not depicted) to supply high voltage electrical energy for a short time to the base portions of said pair of electrodes 5 by means of electrical wiring 9. The electrical energy supplying device comprises: a charger, such as a capacitor, to accumulate high voltage electrical energy; a charging circuit to charge this capacitor; and a discharge circuit to supply the electrical energy charged into the capacitor to the metal wire 6 so as to effect discharge. Also the container 4 is formed of a soft material such as synthetic resin or an elastic material such as rubber. Furthermore, used as the demolishing material 7 is a solid or semisolid material, for example, and to be more specific, it is mortar, mud, silicone, or gel. Used as the granular material 8 is metal balls, pebbles, or ceramic hard balls, for example. In the case of demolishing an object to be demolished, or concrete 2 for example, using said demolishing apparatus using discharge impulse 1, an installation hole 3 is formed in a to-be-demolished portion of said concrete 2, then the container 4, which has the metal wire 6 inserted thereinto, the demolishing material 7 and the granular material 8 filled therein, and a cover element 10 affixed to an opening at the upper end thereof, is inserted into the installation hole 3. Next, the electrical energy supplying device is connected through the electrical wiring 9. Then a discharge switch installed on the discharge circuit is turned on and electrical energy (discharge energy) is supplied to the metal wire 6 for a short time. Whereupon the metal wire 6 suddenly melts and vaporizes. Following this, the demolishing material 7 also vaporizes and transmits the volume expansion force of the metal wire 6 to the concrete 2, such that the volume expansion force, in combination with the vaporization and expansion force of the demolishing material 7, forms a demolishing force and demolishes the concrete 2. Since the granular material 8, such as metal balls, is mixed in the demolishing material 7, the granular material 8 also flies apart into the surroundings with extremely strong force caused by the volume expansion force of the metal wire 6, whereby the concrete 2 is demolished reliably. In this way, since a lot of granular material 8 is mixed in the demolishing material 7, the volume expansion force of the metal wire 6 can be efficiently transmitted to the surroundings. Next, the second embodiment for implementing the present invention is explained on the basis of Fig. 2. The demolishing apparatus using discharge impulse 12 in this second embodiment comprises: a cylindrical container 13 having an opening at both upper and lower ends; a stopper element 14 affixed to the opening at the lower end of the cylindrical container 13; a pair of electrodes 15 inserted in the cylindrical container 13; a metal wire (an example as a melting and vaporizing material, such as copper, iron or aluminum) 16 connecting the end portions of the electrodes 15; a demolishing material 17 and a granular material 18 for filling the cylindrical container 13; and an electrical energy supplying device (not depicted) to supply high voltage electrical energy for a short time to the base portions of the pair of electrodes 15 through electrical wiring 19. The electrical energy supplying device comprises: a charger, such as a capacitor, which accumulates high voltage electrical energy; a charging circuit to charge this capacitor; and a discharge circuit to supply the electrical energy charged in the capacitor to the pair of electrodes 15 so as to effect discharge. Also, the cylindrical container 13 is formed of a hard material such as metal, and the stopper element 14 is formed of a soft material such as thin resin film (wrapping film) used for storing food, vinyl, paper, rubber, thin metal plate or the like. In other words, the stopper element 14 is provided simply to prevent the granular material 18 filled in the cylindrical container 13 from escaping to the outside, and can easily be broken when the volume of the metal wire 16 expands. If the demolishing material 17 is in the solid form such as a gel, the stopper element 14 need not be installed. Further, like in the first embodiment, a solid or semisolid material, for example, is used as the demolishing material 17. To be more specific, it is mortar, mud, silicone, or gel. And, metal balls, pebbles, or ceramic balls, for example, are used as the granular material 18. In order to demolish an object to be demolished, for example concrete 20, by using the foregoing demolishing apparatus using discharge impulse 12, a cylindrical container 13 which has a stopper element 14 attached to the opening at the lower end thereof, a metal wire 16 placed therein, a demolishing material 17 and a granular material 18 both filled therein, and a cover element 21 affixed to the opening at the upper end thereof, is placed on a to-be-demolished portion of the concrete 20. Then, an electrical energy supplying device is connected through electrical wiring 19. Then the discharge switch installed on the discharge circuit is turned on and electrical energy (discharge energy) is supplied to the metal wire 16 in a short time. Whereupon the metal wire 16 suddenly melts and vaporizes. Following this, the demolishing material 17 also vaporizes and transmits the volume expansion force of the metal wire 16 to the concrete 20, said volume expansion force combining with the vaporization and expansion force of the demolishing material 17 to form a demolishing force, thereby demolishing the concrete 20. Since the granular material 8, such as metal balls, is mixed in the demolishing material 7, the granular material 8 also flies apart into the surroundings with extremely strong force due to the volume expansion force of the metal wire 6, whereby the concrete 2 is demolished reliably. Also the granular material 18 mixed in the cylindrical container 13 is filled to a height of half that of the demolishing material 17, for example. Because the granular material 18 is positioned on the side toward the opening in the lower end in the cylindrical container 13, the portion above the granular material 18 functions as a pressure producing portion with only the metal wire 16 placed in the demolishing material 17. Consequently, during the melting and vaporization of the metal wire 16, the granular material 18, positioned on the side toward the opening in the lower end in the container 13, breaks through the stopper element 14 from the cylindrical container 13 like a shotgun shell and is discharged all at once toward the concrete 20, whereby the demolishing force is concentrated by the granular material 18 and the concrete 20 is demolished reliably. Next, the third embodiment for implementing the present invention is explained on the basis of Fig. 3. This demolishing apparatus using discharge impulse 23 in this third embodiment has about the same constitution as the above mentioned second embodiment. The same symbols are applied to the same elements and a detailed explanation thereof is omitted. In other words, as shown in Fig. 3, an extension portion 13a is formed which extends straight just from the cylindrical container 13 below a stopper element 14 provided at the lower end of the cylindrical container 13 in the second embodiment. With this constitution, when an object to be demolished, such as concrete 20, is about to be demolished, the opening on the lower end of the extension portion 31a of the cylindrical container 13 having the metal wire 16, demolishing material 17, and granular material 18 placed therein, is held in the state of being pressed against a to-be-demolished portion of the concrete 20, and electrical energy is supplied to the metal wire 16, whereby the demolishing material 17 and granular material 18 together are ejected toward the concrete 20, with the volume expansion force of the metal wire 16, thereby demolishing the concrete 2. At this time, the straight extension portion 13a of the cylindrical container 13 plays the role of a barrel and guides a large number of granules of the granular material 18 in the same direction, thereby increasing the demolishing force to be even stronger. Next, the fourth embodiment for implementing the present invention is explained on the basis of Fig. 4. In the demolishing apparatus using discharge impulse 23 in the above mentioned third embodiment, the downward extension portion 13a of the cylindrical container 13 was straight in form. However, in the demolishing apparatus using discharge impulse 25 according the fourth embodiment, the extension portion is formed in a conical shape such that the inner diameter of the opening on the lower end of the cylindrical container 13 is greater than the inner diameter of the portion where the stopper element 14 is provided. In addition to the effects obtained from the demolishing apparatus using discharge impulse 23 according to the third embodiment, this constitution allows it to control the volume expansion force of the metal wire 16 and the range of ejection of the granular material 18, which become the demolishing force during the melting and vaporization of the metal wire 16. Next, the fifth embodiment for implementing the present invention is explained on the basis of Figs. 5 and 6. The demolishing apparatus using discharge impulse 27 according to the fifth embodiment comprises: a cylindrical or pouch-shaped demolishing container (hereinafter referred to simply as "container") 28 having a bottom; a pair of electrodes (or conductive wires) 29 inserted in the container 28; a metal wire (an example as a melting and vaporizing material, such as copper, iron or aluminum) 30 connecting the end portions of the electrodes 29; a demolishing material 31 and granular material 32 filling the container 28; a cylindrical holding body 34 which holds the container 28 being filled with the electrodes 29, demolishing material 31 and granular material 32 and having a cover element 33 fixed in the opening at the upper end thereof, and which has an opening at both upper and lower ends thereof; a cover body 35 screwed onto the opening at the upper end of the cylindrical holding body 34; and an electrical energy supplying device (not depicted) to supply high voltage electrical energy in a short time to the base portions of the pair of electrodes 29 through electrical wiring 36. Moreover, a hole portion 35a is formed in the cover body 35 so as to allow passage of the electrodes 29. The electrical energy supplying device comprises: a charger, such as a capacitor, to accumulate high voltage electrical energy; a charging circuit to charge this capacitor; and a discharge circuit to supply electrical energy charged in the capacitor to the pair of electrodes 29 so as to effect discharge. The container 28 is formed of an elastic material such as rubber or a soft material such as synthetic resin. Further, a solid or semisolid material, for example, is used as the demolishing material 31, more specifically, it is mortar, mud, silicone or gel, and metal balls, pebbles or ceramic balls, for example, are used as the granular material 32. When an object to be demolished, such as concrete 37, is demolished using the foregoing demolishing apparatus using discharge impulse 27, the cover element 33 is fixed in the opening portion at the upper end of the container 28 filled with the metal wire 30, demolishing material 31 and granular material 32, as shown in Fig. 5, and subsequently, as shown in Fig. 6, the container 28 is inserted in the cylindrical holding body 34 in such a manner as to face the concrete 37 by being held by a ring-shaped protruding portion (the protruding portion may simply consists of a plurality of protrusions provided at a plurality of locations) 34a protruding at a prescribed location inside the cylindrical holding body 34. Thereafter the cover body 35 is screwed onto the opening at the upper end to hold the entire container 28. The cylindrical holding body 34 holding the container 28 is placed to be pressed against a to-be-demolished portion of the concrete 37. As electrical energy is supplied to the metal wire 30 in this state, powerful demolition can be effected in the same way as in the third embodiment. As discussed above, the demolishing apparatus using discharge impulse relating to the present invention can be advantageously used in the case of demolishing an object to be demolished that requires a great demolishing force.

Claims: A demolishing apparatus using discharge impulse (1, 12, 23, 27) for demolishing an object (2, 20, 37) comprising: a container (4, 13, 28) to be placed into an installation hole (3) formed in a portion to be demolished of the object (2, 20, 37) or onto a portion to be demolished of the object (2, 20, 37); a melting and vaporizing material (6, 16, 30) contained in the container; an electrical supplying device being connected to the melting and vaporizing material (6, 16, 30) and for supplying electrical energy for a short time to the melting and vaporizing material (6, 16, 30), to cause the melting and vaporizing material (6, 16, 30) to suddenly melt and vaporize; and a demolishing material (7, 17, 31) contained in said container (4, 13, 28) to vaporize and expand following the melting and vaporization of the melting and vaporizing material (6, 16, 30); characterised in a granular material (8, 18, 32) being contained in said container (4, 13, 28), to transmit to the surroundings the force of volume expansion generated when the melting and vaporizing material (6, 16, 30) melts and vaporizes and the demolishing material (7, 17, 31) vaporizes and expands and the granular material (8, 18, 32) is ejected toward the object (2, 20, 37) to be demolished. A demolishing apparatus using discharge impulse (1, 12, 23, 27) for demolishing an object (2, 20, 37) according to Claim 1, wherein the container (4, 13, 28) is made of an insulating material such as a synthetic resin or paper, or metal, and comprises a cylindrical holding body (34) having an opening at least at one end thereof in order that the container (28) faces the object (2, 20, 37) to be demolished. A demolishing apparatus using discharge impulse (1, 12, 23, 27) for demolishing an object (2, 20, 37) according to Claim 1, wherein the container (4, 13, 28) is cylindrical and made of a hard material and this cylindrical container (4, 13, 28) includes a soft stopper element (14) provided at an opening at one end of the cylindrical container (4, 13, 28). A demolishing apparatus using discharge impulse (1, 12, 23, 27) for demolishing an object (2, 20, 37) according to Claim 1, wherein the container (4, 13, 28) is cylindrical and made of a hard material; a soft stopper element (14) for holding the demolishing material (7, 17, 31) and granular material (8, 18, 32) is provided in the cylindrical container (4, 13, 28) at a portion partway toward an opening formed at one end thereof; and a space portion is formed between the stopper element (14) and the one end of the cylindrical container (4, 13, 28). A demolishing apparatus using discharge impulse (1, 12, 23, 27) for demolishing an object (2, 20, 37) according to Claim 4, wherein a portion of the cylindrical container (4, 13, 28) corresponding to the space portion formed between the stopper element (14) and the one end is formed in a conical shape such that the inner diameter of the portion on the opening side is greater than the inner diameter on the stopper element (14) side. A demolishing apparatus using discharge impulse (1, 12, 23, 27) for demolishing an object (2, 20, 37) according to any one of Claims 1-5, wherein metal balls, pebbles, or ceramic balls are used as the granular material (8, 18, 32). A demolishing apparatus using discharge impulse (1, 12, 23, 27) for demolishing an object (2, 20, 37) according to any one of Claims 1-5, wherein metal wire is used as the melting and vaporizing material (6, 16, 30).

Inventors: ARAI HIROAKI, INOUE TETSUYA, KATO TSUYOSHI, MAEHATA HIDEHIKO, SASAKI KATSUYA, TAMAKOSHI DAISUKE, ARAI, HIROAKI, INOUE, TETSUYA, KATO, TSUYOSHI, MAEHATA, HIDEHIKO, SASAKI, KATSUYA, TAMAKOSHI, DAISUKE, ARAI, Hiroaki, Hitachi Zosen Corporation, INOUE, Tetsuya, Hitachi Zosen Corporation, KATO, Tsuyoshi, Hitachi Zosen Corporation, MAEHATA, Hidehiko, Hitachi Zosen Corporation, SASAKI, Katsuya, Hitachi Zosen Corporation, TAMAKOSHI, Daisuke, Hitachi Zosen Corporation
Applicants: HITACHI SHIPBUILDING ENG CO, HITACHI ZOSEN CORPORATION
Application year: 1997
Main classification: E04G23
IPC codes: F42D3, E04G23, E01D24