JP2008034670A - Lightning protection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lightning protection device capable of evading a large ground potential rise and minimizing lightning damage in an object to be protected. <P>SOLUTION: The lightning protection device A comprises a lightning protection pole member 1, 50, or 100 mounted on a supporting member T through an insulating body 11A, and a lowering line 14 composed of an insulating coating cable for connecting the lightning protection pole member to a grounding pole body 15 buried in the earth E. The upper surface of the electrode body 2, 51, or 101 which is opposed to a thunder cloud Ct is formed as a parabolic surface like a surface having no projected needle part. Since much charge is simultaneously discharged from many discharge points in a weak force; preceding discharge from the lightning prevention pole member and charges of the lightning cloud are rarely coupled with each other, so that a large feedback current is prevented from flowing between the thunder cloud and the earth E. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a lightning arrester for protecting equipment and the like from lightning damage, and more particularly to a lightning arrester for avoiding lightning strikes around the equipment and the like.

  When thunderclouds are generated and developed in the atmosphere, a leading discharge (step leader) is generated from the cloud bottom of the thundercloud toward the ground, and when this leading discharge progresses, a charge opposite to that of the leading discharge is generated from the ground surface side. The streamer discharge is increased. When the preceding discharge and the streamer discharge are combined, a discharge path is formed between the ground and the thundercloud, and a large current flows between the thundercloud and the ground through the discharge path. This phenomenon is a lightning phenomenon.

  Conventional lightning arresters are configured to receive a lightning strike with a lightning striker located at a higher position than the object to be protected such as equipment including buildings, and to absorb a large current to the ground. It is configured so that no lightning strikes the object to be protected by receiving the lightning strike needle.

  As an example, Patent Document 1 discloses a lightning arrester that receives a lightning strike with a lightning arrester arranged at a position higher than the object to be protected and protects the object to be protected.

JP-A-10-261495

  A conventional lightning arrester that receives lightning strikes with a lightning striker located higher than the object to be protected and absorbs lightning strikes caused by insulation breakdown between the thundercloud and the ground must avoid direct lightning strikes on the object to be protected. Although it is possible, it is extremely difficult to eliminate the lightning strike itself.

  In addition, in the conventional lightning arrester using a lightning striker, the calculation using the angle method, which is the design method for installing the lightning striker, is not necessarily sufficient to protect the object to be protected. However, when recalculated with the rotating sphere method, which is a new design method, a design example in which it is necessary to install a lightning rod at a position higher than 10 m as compared with the angle method. Therefore, there is a problem that the construction cost of the lightning arrester increases.

  Furthermore, when the lightning strike is absorbed into the ground, the increase in the ground potential becomes a high potential, which may adversely affect the object to be protected. Therefore, it is necessary to make the earth ground resistance have a low resistance value, and thus there is a problem that the grounding cost of the lightning arrester increases.

  The objective of this invention is solving the subject which the conventional lightning arrester mentioned above has.

  In order to achieve the above-mentioned object, the present invention provides a lightning pole member installed on a support member via an insulator, and an insulation-coated cable that connects the lightning pole member and a grounding pole body installed on the ground. In the lightning arrester having a pulling line, the first is that the upper surface of the electrode body constituting the lightning pole member facing the thundercloud is formed as a planar discharge surface part having no projecting needle part, In this, the electrode body constituting the lightning protection electrode member is formed in an inverted saddle shape or a ring shape.

  Since this invention has the structure mentioned above, there can exist the effect described below.

  A lightning arrester comprising: a lightning pole member installed on a support member via an insulator; and a pull-down line made of an insulation-coated cable that connects the lightning pole member and a ground pole body installed on the ground. Since the upper surface of the electrode body constituting the member that faces the thundercloud is formed as a planar discharge surface portion without a stylus, a large amount of charge is discharged at a weak moment from many discharge points, Therefore, since the preceding discharge from the lightning pole member and the charge of the thundercloud are extremely difficult to combine, there is no large current return current flowing between the thundercloud and the ground, thus avoiding a large rise in ground potential. Therefore, damage to the object to be protected due to lightning can be minimized.

  Since the electrode body constituting the lightning pole member is formed in an inverted saddle shape or ring shape, the discharge surface portion facing the thundercloud of the electrode body constituting the lightning pole member is formed in a surface shape without a protruding needle portion. Therefore, damage to the object to be protected due to lightning can be more effectively suppressed.

  Examples of the present invention will be described below. However, the present invention is not limited to the examples as long as the gist of the present invention is not exceeded.

  Reference numeral 1 denotes a lightning pole member, and the lightning pole member 1 includes an upper electrode body 2, a lower electrode body 3, and an annular insulator 4. The upper electrode body 2 and the lower electrode body 3 are made of metal and have at least an aerial part. In the present embodiment, the upper electrode body 2 is an inverted bowl-shaped body (a bowl-shaped body) having a hollow inside. The lower electrode body 3 is formed as a bowl-like body having a hollow inside (the opening of the bowl is located above). It is formed as a form that stands up. A hemispherical upper convex portion 2 a is formed at the center of the top portion of the upper electrode body 2, and a hemispherical lower convex portion 3 a is formed at the bottom central portion of the lower electrode body 3. Is formed.

  The peripheral end 2b of the upper electrode body 2 is formed to be thicker than the other portions, and the peripheral end 2b has a plurality of screw holes 2c at predetermined intervals along the circumferential direction. Is formed. Similarly, the circumferential end 3b of the lower electrode body 3 is formed thicker than the other portions, and the circumferential end 3b has a plurality of bolts at predetermined intervals along the circumferential direction. An insertion hole 3c is formed.

  The annular insulator 4 is formed of, for example, a synthetic resin such as a methacrylic resin or an epoxy resin excellent in weather resistance and excellent in strength, or porcelain or the like, and has a high insulation property having a predetermined thickness. It is formed as an annular body. The annular insulator 4 having a through hole 4a in the central region is configured to be sandwiched between the circumferential end 2b of the upper electrode body 2 and the circumferential end 3b of the lower electrode body 3. When the annular insulator 4 is sandwiched between the circumferential end portion 2b of the upper electrode body 2 and the circumferential end portion 3b of the lower electrode body 3, the outer peripheral portion 4b of the annular insulator 4 becomes the upper electrode body. 2 and the lower electrode body 3 are located outside.

  A plurality of bolt insertion holes 4c are formed at predetermined intervals along the circumferential direction in the outer peripheral portion 4b of the annular insulator 4, and the outer peripheral portion 4b of the annular insulator 4 has an annular shape. A plurality of screw holes 4d having a depth from the lower surface 4 ′ of the insulator 4 toward the upper surface 4 ″ of the annular insulator 4 and not reaching the upper surface 4 ″ of the annular insulator 4 are provided at a predetermined interval. Is formed.

  Pa is an upper annular packing having substantially the same outer diameter as the circumferential end 2b of the upper electrode body 2, and the inner diameter of the upper annular packing Pa is the same as or more than that of the through hole 4a of the annular insulator 4. It has a large diameter. The upper annular packing Pa is provided with a bolt insertion hole p1 corresponding to the screw hole 2c formed in the circumferential end 2b of the upper electrode body 2.

  Pb is a lower packing similar to the above-described upper annular packing Pa. The lower packing Pb has substantially the same outer diameter as the circumferential end 3b of the lower electrode body 3, and the inner diameter of the lower annular packing Pb is The diameter is the same as or larger than the through hole 4a of the annular insulator 4. The lower annular packing Pb has a bolt insertion hole p2 corresponding to the bolt insertion hole 3c formed in the circumferential end 3b of the lower electrode body 3.

  The upper electrode body 2 and the lower electrode body are respectively interposed via the upper annular packing Pa and the lower packing Pb so that the circumferential end 2b of the upper electrode body 2 and the circumferential end 3b of the lower electrode body 3 face each other. 3, when the annular insulator 4 is sandwiched, the bolt insertion hole 4 c formed in the outer peripheral portion 4 b of the annular insulator 4, the bolt insertion hole p 1 formed in the upper annular packing Pa, and the upper electrode body The screw hole 2c formed in the circumferential end portion 2b of the 2 is linearly aligned in the vertical direction, and the screw hole 4d formed in the outer periphery portion 4b of the annular insulator 4 is formed in the lower annular packing Pb. The bolt insertion hole p2 and the bolt insertion hole 3c formed in the circumferential end 3b of the lower electrode body 3 are configured to coincide with each other in a straight line in the vertical direction. And the bolt insertion hole 4c drilled in the outer peripheral part 4b of the cyclic | annular insulator 4 arrange | positioned linearly in the up-down direction, and the screw hole 2c formed in the circumferential end part 2b of the upper electrode body 2 A screw hole 4d formed in the outer peripheral portion 4b of the annular insulator 4 arranged in a straight line in the vertical direction, and a bolt insertion hole 3c formed in the peripheral end portion 3b of the lower electrode body 3. Are arranged so as to be displaced in the circumferential direction. Further, the lower electrode body 3 has a vertical screw hole 3d so as to be directed upward from the central lower surface of the lower electrode body 3 where the hemispherical lower convex portion 3a is located and so as not to penetrate the lower convex portion 3a. Is formed.

  The upper annular packing Pa is arranged on the upper surface 4 ″ of the annular insulator 4, and then the circumferential end 2b of the upper electrode body 2 is arranged on the upper surface 4 ″ of the annular insulator 4 via the upper annular packing Pa. Similarly, the lower annular packing Pb is disposed on the lower surface 4 ′ of the annular insulator 4, and then the circumferential shape of the lower electrode body 3 is disposed on the lower surface 4 ′ of the annular insulator 4 via the lower annular packing Pb. By arranging the end portion 3b, the upper electrode body 2 and the lower electrode body 3 are annularly insulated so that the circumferential end portion 2b of the upper electrode body 2 and the circumferential end portion 3b of the lower electrode body 3 face each other. Hold the body 4. Thereafter, a bolt insertion hole 4c drilled in the outer peripheral portion 4b of the annular insulator 4 in a state of being aligned linearly in the vertical direction, a bolt insertion hole p1 drilled in the upper annular packing Pa, and the periphery of the upper electrode body 2 The bolt B is inserted from below the annular insulator 4 into the screw hole 2c formed in the end portion 2b, and the screw portion b1 formed at the tip of the bolt B is connected to the circumferential shape of the upper electrode body 2 The annular insulator 4 is attached to the upper electrode body 2 via the upper annular packing Pa by screwing into the screw hole 2c formed in the end 2b. Similarly, a bolt insertion hole 3c formed in the circumferential end 3b of the lower electrode body 3 in a state of being aligned linearly in the vertical direction, a bolt insertion hole p2 drilled in the lower annular packing Pb, and an annular insulator The bolt B is inserted from below the lower electrode body 3 into the screw hole 4d formed in the outer peripheral portion 4b of the screw 4, and the screw portion b1 formed at the tip of the bolt B is inserted into the outer periphery of the annular insulator 4. The insulator 4 is attached to the lower electrode body 3 through the lower annular packing Pb by being screwed into the screw hole 4d formed in the portion 4b. Thus, the lightning pole member 1 in which the annular insulator 4 is sandwiched by the upper electrode body 2 and the lower electrode body 3 is assembled via the upper annular packing Pa and the lower annular packing Pb. A hemispherical upper convex portion 2a formed at the center of the top of the upper electrode body 2 constituting the lightning protection electrode member 1, and a hemispherical lower convex portion 3a formed at the center of the bottom of the lower electrode body 3; Are arranged so as to face each other in the vertical direction. The upper annular packing Pa and the lower annular packing Pb can be omitted as appropriate.

  Since the screw hole 4d formed in the annular insulator 4 is formed to a depth that does not reach the upper surface 4 ″ of the annular insulator 4, a bolt insertion hole formed in the circumferential end 3b of the lower electrode body 3 A bolt B that is inserted into 3c from below and screwed into a screw hole 4d formed in the outer peripheral portion 4b of the annular insulator 4 passes through the annular insulator 4, and the tip of the bolt B is connected to the upper electrode. The upper electrode body 2 and the lower electrode body 3 are in contact with the circumferential end 2b of the body 2 and are not electrically connected via the bolt B.

  Reference numeral 5 denotes a long support bolt made of a conductive material such as metal with a screw engraved around it. Reference numeral 6 denotes a substantially cylindrical pedestal. On the upper surface of the pedestal 6, a mounting recess 6 a is formed so that the lower surface central portion of the lower electrode body 3 comes into surface contact. The insertion hole 6 b through which the long support bolt 5 can be inserted is formed, and a fitting recess 6 c is formed in the lower part of the base 6.

  Reference numeral 7 denotes a cylindrical protective cylinder made of synthetic resin or metal. Reference numeral 8 denotes a holding body composed of a circumferential wall 8a and a top portion 8b. An annular step portion 8c is formed at an upper corner of the top portion 8b. Is formed at the upper end portion of the top portion 8b, and a cylindrical convex portion 8d into which the lower end portion of the protective cylinder 7 can be fitted is formed. Further, a long support is provided at the center portion of the top portion 8b. An insertion hole 8e through which the bolt 5 can be inserted is formed.

  Next, the lightning pole member comprising the upper electrode body 2, the lower electrode body 3, and the annular insulator 4 sandwiched between the upper electrode body 2 and the lower electrode body 3 via the upper annular packing Pa and the lower annular packing Pb. The attachment to the 1 long support bolt 5 is demonstrated.

  First, the pedestal 6 is arranged so that the mounting recess 6 a of the pedestal 6 is in surface contact with the center of the lower surface of the lower electrode body 3 constituting the lightning protection electrode member 1. Next, the upper end of the long support bolt 5 is inserted into the insertion hole 6 b of the base 6, and the upper end of the long support bolt 5 is screwed into a vertical screw hole 3 d formed in the lower electrode body 3. Thereafter, the nut N is screwed onto the long support bolt 5 via the washer W, and the nut N is tightened so as to contact the pedestal 6 from below via the washer W. The lightning pole member 1 is attached to the upper end of the bolt 5.

  Next, the protective cylinder 7 is arranged so as to surround the long support bolt 5, and the upper end portion of the protective cylinder 7 is fitted into the fitting recess 6 c of the pedestal 6, and then to the top portion 8 b of the holding body 8. The lower end portion of the long support bolt 5 is inserted into the drilled insertion hole 8e, and the lower end portion of the protective cylinder 7 is fitted to the cylindrical convex portion 8d of the holding body 8. Next, the nut N is screwed from the lower end of the long support bolt 5 so that the nut N is positioned in the circumferential wall 8a of the holding body 8 and is brought into contact with the top portion 8b. Thus, the lightning arrester A including the base 6, the long support bolt 5, the holding body 8 and the like is formed. The lower end of the long support bolt 5 has a predetermined length and is exposed from the holding body 8, and a washer can be interposed between the nut N and the top portion 8b of the holding body 8. . By arranging the protective cylinder 7 so as to surround the long support bolt 5, the long support bolt 5 is configured not to rust.

  Next, attachment of the lightning arrester A to the support member T such as a steel tower or a steel pillar will be described. The support member T is directly erected on the ground E or is erected on a building. In the present embodiment, an example is shown in which a supporting member T such as a steel tower or a steel pillar is erected on a base F embedded in the ground E.

  An object 10 to be protected such as an antenna is attached to the upper portion of the support member T via an appropriate attachment 9. A high-insulation insulator 11A such as an insulator is attached to the upper end portion of the support member T, and a flange 12 made of a conductive material such as metal is attached to the upper end portion of the insulator 11A. On the upper surface of the flange 12, a connecting flange 13 made of a conductive material such as a metal having a screw hole 13a is attached at the center with an appropriate fixing tool such as a bolt and a nut. Then, by screwing the lower end portion of the long support bolt 5 constituting the lightning arrester A described above into the screw hole 13a of the connecting flange 13, the lightning arrester A is attached to the support member T via the insulator 11A. Install.

  Reference numeral 14 denotes a pull-down line made of an insulation-coated cable. An upper end portion of the pull-down line 14 is connected to the connecting flange 13, and a lower end portion of the pull-down line 14 is a grounding electrode body 15 installed on the ground E. It is connected to the. Reference numeral 16 denotes a fastening band for fixing the pull-down line 14 to the support member T.

  Next, the operation of the lightning arrester A attached to the support member T through an insulator 11A such as an insulator will be described.

  When a thundercloud Ct matured in the atmosphere approaches the lightning arrester A attached to the upper part of the object 10 to be protected, the charge distributed on the cloud bottom of the thundercloud Ct (mostly a negative charge, which is described as a negative charge) In other words, on the surface of the ground E, a charge opposite to the negative charge distributed on the cloud bottom of the thundercloud Ct, that is, a positive charge is distributed. When the positive charge distributed on the surface of the ground E reaches a saturation level, the lightning pole member 1 having the same potential as the ground E is formed via the grounding pole body 15 and the pull-down line 14 installed on the ground E. Charges opposite to the charges of the thundercloud Ct, that is, positive charges are collected on the lower electrode body 3. Then, the upper electrode body 2 attached to the lower electrode body 3 via the annular insulator 4 works so as to eliminate the potential difference from the lower electrode body 3, so that it is opposite to the positive charge of the lower electrode body 3. Therefore, the negative charge distributed in the thundercloud Ct is not saturated, and the occurrence of lightning can be avoided. Further, the negative charge collected in the upper electrode body 2 and the positive charge in the lower electrode body 3 are neutralized through the annular insulator 4 and the surrounding air.

  As described above, the lower electrode body 3 has a charge opposite to that of the thundercloud Ct (the same charge as the ground), and the upper electrode body 2 eliminates the potential difference from the lower electrode body 3. Therefore, in order to collect the charge opposite to the charge of the lower electrode body 3 from the surrounding atmosphere, the atmosphere does not reach a condition for causing a lightning strike, and therefore it is possible to avoid the occurrence of a lightning strike. Further, an increase in the ground potential can be avoided, and accordingly, a high voltage of the ground potential is not generated in the object to be protected 10, so that no dielectric breakdown occurs.

  The lower electrode body 3 is configured so that the lower electrode body 3 has a pull-down line 14 by setting the ground electrode body 15 installed on the ground E to an annular ground or a mesh ground disposed so as to surround the object 10 to be protected when viewed in plan. Via the ground electrode body 15 to obtain a charge of the ground E (a charge opposite to that of the thundercloud Ct), and the upper electrode body 2 is actively activated so as to eliminate the potential difference with the lower electrode body 3. It becomes active to obtain a charge opposite to the charge held by the lower electrode body 3 from the surrounding atmosphere, and as a result, lightning can be further avoided.

  Furthermore, the operation states of the thundercloud Ct and the lightning arrester A will be described in detail.

  When a thundercloud Ct is generated and approaches the lightning arrester A, the charge on the surface of the ground E is opposite to the charge distributed on the cloud bottom of the thundercloud Ct (mostly a negative charge and will be described as a negative charge). That is, it will be positively charged. When the positive charge distributed on the surface of the ground E reaches a saturation level, the lightning pole member 1 having the same potential as the ground E is formed via the grounding pole body 15 and the pull-down line 14 installed on the ground E. Charges opposite to the charges of the thundercloud Ct, that is, positive charges are collected on the lower electrode body 3. On the other hand, the upper electrode body 2 collects a negative charge opposite to the positive charge of the lower electrode body 3 from the surrounding atmosphere in order to eliminate the potential difference with the lower electrode body 3.

  The negative charge of the upper electrode part 2 and the positive charge of the lower electrode part 3 are passed through a through hole 4a drilled in the annular insulating part 4, and the upper convex part 2a of the upper electrode body 2 and the lower convex part 3a of the lower electrode body 3 are used. The positive charge and the negative charge start to move between the positive electrode and the negative electrode. Then, the charge transfer gradually spreads over the entire upper electrode body 2 and the lower electrode body 3, and the charges move actively. Charge transfer occurs via 4. Further, when the thundercloud Ct approaches the lightning arrester A, the charge level moves more actively, a small current flows, and the upper electrode body 2 actively activates negative charges from the atmosphere around the lightning pole member 1. And the saturation of the negative charge in the atmosphere around the lightning pole member 1 is eliminated, and therefore the occurrence of a lightning strike is avoided. Thus, since the upper convex part 2a was formed in the top center part of the upper electrode body 2, and the lower convex part 3a was formed in the bottom center part of the lower electrode body 3, the upper electrode body 2 and the lower electrode body 3 are formed. Can be started reliably and quickly.

  The charge transfer phenomenon through the annular insulator 4 in the upper electrode body 2 and the lower electrode body 3 constituting the lightning protection pole member 1 starts when the thundercloud Ct approaches, and becomes active as the thundercloud Ct approaches, and becomes active as the thundercloud Ct moves away. Will continue to occur until the thundercloud leaves.

  According to the field test, the outer diameter of each of the upper electrode body 2 formed as an inverted rod-shaped body and the lower electrode body 3 formed as a bowl-shaped body is set to a radius of 100 mm, and the plate thickness of the annular insulator 4 is set to 40 mm. Furthermore, as a result of selecting a well-known area with a large number of lightning strikes in advance and installing the above-described lightning arrester A on the support member T, no lightning strikes occurred within a radius range of 200 m.

  As described above, since lightning can be avoided, an increase in ground voltage due to a large current caused by lightning can be avoided, and thus the object to be protected can be protected from high voltage.

  In addition, since it has a protection range by the angle method using the lightning arrester needle and the rotating sphere method, it is not necessary to install it at a higher place, and if the lightning arrester A is installed at a higher position than the object 10 to be protected. Therefore, the construction cost of the support member T such as a steel tower or steel pillar can be reduced.

  Furthermore, by installing the lightning arrester A having the above-described configuration, the lightning protection range is wide, and the surrounding area can also benefit from the protection range.

  In the embodiment described above, an example is shown in which the upper electrode body 2 and the lower electrode body 3 constituting the lightning protection pole member 1 are formed as a rod-shaped body that divides a hollow sphere inside. The structure is not limited to a body, and may be a box-like structure in which a hollow rectangular body is divided in half.

  In addition, the upper electrode body 2 and the lower electrode body 3 can be enlarged, and the annular insulating portion 4 can be made larger and thicker, thereby increasing the charge C level collection capability.

  In the above-described embodiment, an example in which the upper electrode body 2 and the lower electrode body 3 are formed as an inverted bowl-shaped body and a bowl-shaped body having a hollow inside is shown. The lower electrode body 3 has at least a hollow portion, and the hollow portion of the upper electrode body 2 and the hollow portion of the lower electrode body 3 are disposed so as to face each other with the annular insulator 4 interposed therebetween, The hollow part of the upper electrode body 2 and the hollow part of the lower electrode body 3 only need to communicate with each other through the through hole 4a of the annular insulator 4, and the shapes of the upper electrode body 2 and the lower electrode body 3 are reversed. The shape is not limited to a rod-shaped body or a rod-shaped body.

  The shape of the upper electrode body 2 is preferably an inverted saddle-like body having no edges or corners. In this way, by making the upper electrode body 2 an inverted rod-shaped body, the upper electrode body 2 for preventing lightning strikes has no edges or corners, so lightning strikes are less likely to occur. On the other hand, since the lower electrode body 3 is unlikely to be a lightning strike point in the first place, it may be in a cylindrical shape or a rectangular tube shape as long as it has a hollow portion.

  Next, the lightning pole member 50 having a configuration different from that of the above-described lightning pole member 1 will be described with reference to FIGS. 6 and 7, but the constituent members other than the lightning pole member 1 are substantially the same. In the following, only the lightning pole member 50 having a configuration different from that of the lightning pole member 1 will be described.

  In the present embodiment, the lightning protection pole member 50 includes an electrode body 51 having a hollow interior and a reverse bowl shape (a form in which the bowl has an open part positioned downward, a bowl-like shape), and the electrode body 51. The cylindrical portion 52 has a cylindrical portion 52 that is suspended from the center of the top portion, and the cylindrical portion 52 has a screw hole 53 formed upward from the lower end. The cylindrical portion 52 can be configured to be positioned in the electrode body 51, or the cylindrical portion 52 can be configured to extend downward beyond the lower end peripheral edge 51 a of the electrode body 51.

  The lightning protection pole member 50 described above is engaged with the upper end portion of the long support bolt 5 by screwing the upper end portion of the long support bolt 5 into the screw hole 53 formed in the cylindrical portion 52 via the base 6. The lightning pole member 50 is attached.

  Next, a further lightning pole member 100 having a different configuration from the above-described lightning pole member 1 will be described with reference to FIGS. 8 and 9, but the constituent members other than the lightning pole member 1 are substantially the same. Therefore, in the following, only the lightning pole member 100 having a configuration different from that of the lightning pole member 1 will be described.

  In the present embodiment, the lightning pole member 100 is composed of a ring-shaped electrode body 101 and a bowl-shaped inner space connected to the lower portion of the electrode body 101 (the open portion of the bowl is positioned above). And a cylindrical portion 103 suspended from the center of the lower surface of the supporting portion 102, and the cylindrical portion 103 has screw holes 104 extending upward from the lower end. Is formed. The outer diameter D1 of the ring-shaped electrode body 101 is formed larger than the thickness D2 of the support portion 102. The support portion 102 connects the ring-shaped electrode body 101 and the cylindrical portion 103, and the shape is not limited to a bowl shape, and can be connected by a rod body, a plate material, or the like. .

  The lightning pole member 100 described above is screwed into the upper end portion of the long support bolt 5 by screwing the upper end portion of the long support bolt 5 into the screw hole 104 formed in the cylindrical portion 103 via the base 6. The lightning pole member 100 is attached.

  By the way, as described above, a discharge path is formed between the thundercloud Ct and the ground E by the combination of the preceding discharge generated from the cloud bottom of the thundercloud Ct toward the ground E and the streamer discharge from the ground surface side. The lightning phenomenon that occurs when a high current feedback current flows between the thundercloud Ct and the ground E through this discharge path is a lightning phenomenon that occurs frequently in summer.

  On the other hand, when the thundercloud Ct is generated, the preceding discharge may be generated from the ground E side toward the thundercloud Ct. If this upward discharge is not combined with the charge of the thundercloud Ct, the discharge time is long. Since the lightning current is small, the damage to the protected object 10 is small.

  Moreover, when the preceding discharge generated from the ground E side toward the thundercloud Ct is combined with the streamer discharge from the thundercloud Ct, the energy is large because the discharge time is longer than the lightning phenomenon in summer. A large feedback current flows from the thundercloud Ct, resulting in a large lightning phenomenon. Such a lightning phenomenon is a lightning phenomenon that occurs frequently in winter, and occurs frequently especially on the Sea of Japan side. In this way, the lightning phenomenon that occurs frequently in winter, in which the preceding discharge generated from the ground E side toward the thundercloud Ct and the streamer discharge from the thundercloud Ct are combined, the return current from the thundercloud Ct is large, and the protected object 10 Will cause a lot of damage.

  Below, the operation | movement of the lightning arrester A in which the lightning pole members 1, 50, 100 at the time of the lightning phenomenon as described above, which is common in winter, will be described.

  When a thundercloud Ct matured in the atmosphere approaches the lightning arrester A attached to the upper part of the object 10 to be protected, it is induced by the charge of the thundercloud Ct, and the ground surface E of the ground E having a charge opposite to that of the thundercloud Ct. The electric charge is distributed to the lightning pole members 1, 50, 100 of the lightning arrester A through the pull-down line 14 made of an insulation-coated cable. When the electric charges of the lightning pole members 1, 50, 100 are at a certain level, no discharge occurs. However, when the charge reaches a predetermined level, the upper electrode body 2 or the lightning pole member 50 of the lightning pole member 1 is reached. The preceding discharge is generated from the electrode body 51 or the electrode body 101 of the lightning protection electrode member 100 toward the thundercloud Ct. The impedance of the pull-down line 14 causes the ground E to pass through the pull-down line 14. The upper surface of the top electrode body 2 of the lightning pole member 1, the electrode body 51 of the lightning pole member 50, or the electrode body 101 of the lightning pole member 100 facing the thundercloud Ct Unlike the lightning rod, it is formed as a planar discharge surface portion having a large area, so that a large amount of charge is discharged at a weak moment from many discharge points. Therefore, the extension distance of the preceding discharge from the lightning pole members 1, 50, 100 toward the thundercloud Ct is short, and it is difficult to reach the thundercloud Ct. Therefore, the preceding discharge is not combined with the electric charge of the thundercloud Ct, and the occurrence of a lightning phenomenon can be prevented.

  In addition, as described above, since the electrode bodies 2, 51, 101 constituting the lightning pole members 1, 50, 100 are formed in an inverted saddle shape or ring shape, the electrodes constituting the lightning pole members 1, 50, 100 Since the discharge surface portion facing the thundercloud Ct of the bodies 2, 51, and 101 is formed in a surface shape without a protruding needle portion, damage to the object to be protected 10 due to lightning can be more effectively suppressed.

FIG. 1 is a vertical sectional view of a lightning arrester of the present invention. FIG. 2 is an exploded perspective view of the lightning arrester of the present invention. FIG. 3 is a front view of the lightning arrester of the present invention attached to the support member. 4 is a partially enlarged front view of FIG. 3 including a partial cross-section. FIG. 5 is a front view of the lightning arrester of the present invention in a state attached to the thundercloud and the support member. FIG. 6 is a front view of a lightning pole member of another embodiment that constitutes the lightning arrester of the present invention. FIG. 7 is a vertical sectional view of the lightning pole member shown in FIG. FIG. 8 is a front view of a lightning pole member of still another embodiment constituting the lightning arrester of the present invention. FIG. 9 is a vertical sectional view of the lightning pole member shown in FIG.

Explanation of symbols

A ... Lightning arrester B ... Bolt N ... Nut Pa ...・ ・ ・ ・ ・ Upper ring packing Pb ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Lower ring packing T ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Supporting member 1, 50, 100 ・ ・ ・ ・ ・ Lightning pole Member 2 ... Upper electrode body 3 ... Lower electrode body 4 ... Ring insulator 5 ···························· Long support bolt ······························································· 11・ Pull down line 15 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Grounding electrode 51, 101 ・ ・ ・ ・ ・Electrode body

Claims (2)

  A lightning arrester comprising: a lightning pole member installed on a support member via an insulator; and a pull-down line made of an insulation-coated cable connecting the lightning pole member and a ground pole body installed on the ground. A lightning arrester characterized in that the upper surface of the electrode body constituting the member facing the thundercloud is formed as a planar discharge surface portion without a protruding needle portion.   2. The lightning arrester according to claim 1, wherein the electrode body constituting the lightning arrester electrode member is formed in an inverted saddle shape or a ring shape.

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