Cylindrical Cutout

Abstract

To provide a cylindrical cutout that can suppress the occurrence of a flashover.SOLUTION: A cylindrical cutout is connected to a distribution line and a high-voltage device side wiring. The cylindrical cutout includes an upper cutout body having an upper electrode inside that is connected to both the distribution line and a fuse cylinder and a lower cutout body that has a lower electrode inside that is connected to both the high-voltage device side wiring and the fuse cylinder. The upper cutout body also has an upper umbrella portion to increase the creepage distance on the outer surface of the cylindrical cutout. The cylindrical cutout is provided with a first protrusion protruding toward the outer radial direction at a radial end portion of the upper umbrella portion.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] This specification discloses a technique relating to a cylindrical cutout that is connected to a power distribution line and high-voltage equipment wiring. [Background technology]

[0002] To protect a transformer or the like, a cylindrical cutout is placed between a distribution line and wiring on the high-voltage equipment side. The cylindrical cutout of Patent Document 1 has an umbrella portion (pleats) on its outer periphery to increase the creepage distance of the outer surface. The cylindrical cutout of Patent Document 1 is fixed to a mounting member such as a utility pole using a mounting bracket. The mounting bracket is fixed to the cylindrical cutout below the umbrella portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-186208 Summary of the Invention [Problem to be solved by the invention]

[0004] When the mounting bracket is attached below the umbrella portion, the distance between the bottom end of the umbrella portion and the mounting bracket becomes short. This short distance between the bottom end of the umbrella portion and the mounting bracket may cause a flashover between the umbrella portion and the mounting bracket. Therefore, a cylindrical cutout that is less susceptible to flashover is needed. The present specification aims to provide a cylindrical cutout that can suppress the occurrence of flashover. [Means for solving the problem]

[0005] The cylindrical cutout disclosed in this specification is connected to a power distribution line and high-voltage equipment wiring. This cylindrical cutout includes an upper cutout body having an upper electrode therein connected to both the power distribution line and the fuse barrel, and a lower cutout body having a lower electrode therein connected to both the high-voltage equipment wiring and the fuse barrel. The upper cutout body also has an upper umbrella portion for increasing the creepage distance on the outer surface of the cylindrical cutout. In this cylindrical cutout, a first protrusion protruding radially outward is provided at a radial end of the upper umbrella portion. [Brief explanation of the drawings]

[0006] [Figure 1] 1 shows a cross-sectional view of a cylindrical cutout. [Figure 2] FIG. 2 shows a side view of the upper cutout body of the first embodiment. [Figure 3] 1 shows a partial cross-sectional view of the upper cutout body of the first embodiment. [Figure 4] FIG. 2 shows a front view of the upper cutout body of the first embodiment. [Figure 5] 1 shows the cylindrical cutout of the first embodiment with a fixing member attached thereto. [Figure 6] 10 shows the cylindrical cutout of the second embodiment with a fixing member attached thereto. [Figure 7] FIG. 10 shows a front view of the upper cutout body of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] (cylindrical cutout) The cylindrical cutout is connected between a power distribution line and a high-voltage device such as a transformer via an external electric wire. The cylindrical cutout includes a cylindrical cutout body and a fuse barrel (power fuse) disposed within the cylindrical cutout body. The power fuse is connected to an upper electrode and a lower electrode disposed within the cylindrical cutout body. The upper electrode is connected to the power distribution line, and the lower electrode is connected to the wiring on the high-voltage device side.

[0008] (Cylindrical cutout body) The cylindrical cutout body is made of an insulating material (resin). Specifically, the cylindrical cutout body is composed of an upper cutout body made of an insulating material and a lower cutout body made of an insulating material. An example of the insulating material is an ethylene-based resin with added carbon black. An upper electrode is housed in the upper cutout body, and a lower electrode is housed in the lower cutout body. Such a cylindrical cutout body can be made lighter in weight than a conventional cylindrical cutout body that is partially or entirely made of ceramic.

[0009] A cylindrical covering portion may be provided on one of the upper cutout body and the lower cutout body, and a cylindrical insert portion may be provided on the other. For example, if the upper cutout body is provided with a covering portion and the lower cutout body is provided with an insert portion, the upper cutout body and the lower cutout body are fixed together when the insert portion is inserted into the covering portion. That is, the covering portion covers the lower cutout body (insertion portion). A power fuse is disposed in the insertion portion. Furthermore, the covering portion and the insert portion may be fixed together by providing a groove on one of the covering portion and a protrusion on the other, and engaging the groove with the protrusion. This eliminates the need for adhesives, fasteners, etc. for fixing the upper cutout body and the lower cutout body. This reduces the number of parts in the cylindrical cutout and makes it easier to disassemble (sort) the cylindrical cutout when disposing of it.

[0010] When the upper cutout body is provided with a covering portion and the lower cutout body is provided with an insert portion, the upper electrode may be fixed to the upper cutout body while contacting the insert portion. That is, the upper electrode may be sandwiched between the upper cutout body and the insert portion (part of the lower cutout body) and fixed (positioned) within the upper cutout body. This eliminates the need for adhesives, fasteners, etc. for fixing the upper electrode to the upper cutout body. This reduces the number of parts in the cylindrical cutout and makes it easier to disassemble the cylindrical cutout when disposing of it.

[0011] (Top cutout body) The upper cutout body may be provided with an upper umbrella portion for increasing the creepage distance of the outer surface of the cylindrical cutout. This can improve the insulating performance of the cylindrical cutout. Furthermore, a first protrusion protruding radially outward may be provided at a radial end of the upper umbrella portion. In this case, a circumferential portion of the first protrusion may be provided at a higher position than the other portions. Furthermore, another circumferential portion of the first protrusion may be provided at a lower position than the other portions. The first protrusion may be inclined from an upper position to a lower position. In this case, water droplets (rainwater, etc.) adhering to the upper umbrella portion flow over the first protrusion from the upper position to the lower position.

[0012] When the upper cutout body is provided with a covering portion and the lower cutout body is provided with an insertion portion, an insertion hole into which a portion of the upper electrode is inserted may be provided at the upper end of the insertion portion. For example, the upper electrode may have a pair of gripping portions for gripping a power fuse, and the pair of gripping portions may be inserted into the insertion hole. This allows for more reliable positioning of the upper electrode within the cylindrical cutout body. Also, this allows for more reliable engagement between the upper electrode and the upper side electrode of the power fuse disposed within the insertion portion.

[0013] As described above, the upper electrode is connected to the power distribution line. The upper cutout body, the upper electrode, and the lower cutout body can be more firmly fixed together using a fixing member for connecting (fixing) the upper electrode to the power distribution line. Specifically, a connecting portion for connecting the pair of gripping portions is formed in the upper electrode. A through hole (first through hole) is then formed in the connecting portion. A through hole (second through hole) communicating with the outside of the upper cutout body is also formed in the upper cutout body. The second through hole is formed in a position facing the connecting portion (first through hole) of the upper electrode. Furthermore, an upper surface portion for closing a portion of the upper end of the insertion portion is formed in the lower cutout body. A through hole (third through hole) is then formed in the upper surface portion. The third through hole is also formed in a position facing the connecting portion (first through hole) of the upper electrode. A fixing member for connecting the upper electrode to the power distribution line is then passed through the first, second, and third through holes and fixed to the fixed portion of the power distribution line. As a result, the upper cutout body, the upper electrode, and the lower cutout body are fixed by the fixing member.

[0014] When the upper cutout body is provided with a covering portion and the lower cutout body is provided with an insertion portion, a mounting bracket for attaching the cylindrical cutout to another member (such as a utility pole) may be fixed to the covering portion. In this case, the surface of the covering portion may be provided with a first restricting portion that protrudes toward the outside of the covering portion and restricts vertical movement of the mounting bracket, and a second restricting portion that protrudes toward the outside of the covering portion and restricts circumferential movement of the mounting bracket. This allows the mounting bracket to be firmly attached to the cylindrical cutout. In other words, the cylindrical cutout can be positioned relative to the mounting bracket.

[0015] The first restricting portion may be provided on at least one of both side surfaces of the cylindrical cutout in a first direction perpendicular to the axis of the cylindrical cutout. The second restricting portion may be provided on at least one of both side surfaces of the cylindrical cutout in a second direction perpendicular to the axis of the cylindrical cutout and the first direction. In other words, the first restricting portion and the second restricting portion may be provided at positions offset by approximately 90 degrees in the circumferential direction of the cylindrical cutout. This makes it possible to avoid overlapping between the portion restricting vertical movement of the cylindrical cutout and the portion restricting circumferential movement of the cylindrical cutout.

[0016] The first restricting portion may be a pair of protrusions spaced apart in the vertical direction of the covering portion. The second restricting portion may also be a pair of protrusions spaced apart in the circumferential direction of the covering portion. In this case, the second restricting portion is provided on both sides in the second direction, and the spacing between the pair of protrusions on one side may be narrower than the spacing between the pair of protrusions on the other side. Typically, the mounting bracket is attached to the cylindrical cutout by tightening the front end (the side farther from the workpiece (such as a utility pole) to which the cylindrical cutout is attached) with a bolt. By providing a second restricting portion with narrow protrusion spacing on one side, the bolt tightening margin can be ensured. In this case, the pair of protrusions on one side engage with a bent portion of the mounting bracket on the side opposite the workpiece to which the cylindrical cutout is attached. The pair of protrusions on the other side engage with a bent portion of the mounting bracket on the side of the workpiece to which the cylindrical cutout is attached.

[0017] (Bottom cutout body) The lower cutout body may have a cylindrical portion that houses the lower electrode. The cylindrical portion may have a cylindrical protrusion through which high-voltage equipment wiring connected to the lower electrode passes. The protrusion may extend radially outward from the outer circumferential surface of the cylindrical portion. The radial size of the cylindrical portion may be smaller than the radial size of the upper umbrella portion. This prevents the cylindrical portion from getting wet with rainwater, etc.

[0018] (Lower umbrella part) In addition to the upper cutout body and the lower cutout body, the cutout body may have an umbrella member (lower umbrella portion) attached to the covering portion of the upper cutout body to increase the outer surface length of the cylindrical cutout in the vertical direction. Attaching an umbrella member to the covering portion can further improve the insulating performance of the cylindrical cutout. When the umbrella member is attached to the covering portion, a fixing portion may be provided on the outer surface of the covering portion to fix the umbrella member to the covering portion. Parts (bolts, etc.) for fixing the umbrella member to the covering portion (upper cutout body) can be omitted. When the umbrella portion (upper umbrella portion) is provided on the upper cutout body, the umbrella member may be provided below the upper umbrella portion. In other words, when the umbrella portion () is provided on the upper cutout body, the umbrella portion attached to the upper cutout body can be considered as the lower umbrella portion. Furthermore, a second protrusion protruding radially outward may be provided at the radial end of the lower umbrella portion. [Example]

[0019] (First Example) Referring to FIG. 1, a high-voltage cutout 100 will be described. The high-voltage cutout 100 is installed on a power distribution line and is used to protect equipment such as transformers. The exterior of the high-voltage cutout 100 is mainly composed of a resin upper cutout body 30, a resin lower cutout body 70, and a resin lower umbrella portion 50. The upper cutout body 30, the lower cutout body 70, and the lower umbrella portion 50 are formed of an insulating material containing an ethylene-based material. Specifically, the insulating ethylene-based material is an ethylene-based resin with added carbon black. As will be described in detail later, the upper cutout body 30 and the lower cutout body 70 are fixed together, and the lower umbrella portion 50 is fixed to the upper cutout body 30.

[0020] The high-voltage cutout 100 is installed so that the upper cutout body 30 is on the upper side and the lower cutout body 70 is on the lower side in the direction of gravity. A fuse cylinder 8 and an arc-extinguishing cylinder 6 are arranged inside the high-voltage cutout 100. The fuse cylinder 8 is arranged inside the arc-extinguishing cylinder 6. The fuse cylinder 8 extends in the vertical direction and connects the upper electrode 4 and the lower electrode 12. A fuse 10 is arranged inside the fuse cylinder 8. A conical upper molded cone 3 is fixed to the top of the upper cutout body 30. A lead wire 1 passes through the upper molded cone 3. The lead wire 1 is electrically connected to the upper electrode 4 and is connected to a power distribution line. A lower molded cone 16 is fixed to the side of the lower cutout body 70. A lead wire 18 passes through the lower molded cone 16. The lead wire 18 is electrically connected to the lower electrode 12 via a connection plate 14 and is connected to equipment such as a transformer. Each of the components that make up the high voltage cutout 100 will now be described in detail.

[0021] The upper cutout body 30 will be described with reference to FIGS. 2 to 4. As shown in FIG. 2, the upper cutout body 30 mainly comprises an upper umbrella portion 32 and a covering portion 36. The covering portion 36 is cylindrical and covers a portion of the lower cutout body 70. The lower cutout body 70 will be described in detail below. A protrusion 31 is provided at the upper end of the upper umbrella portion 32, i.e., the upper end of the upper cutout body 30. The upper umbrella portion 32 widens in diameter from top to bottom, and a first protrusion 34 is provided at the radial end of the lower end (see also FIG. 1). The first protrusion 34 runs around the outer periphery of the upper umbrella portion 32. The first protrusion 34 protrudes the same distance from the upper umbrella portion 32 in the circumferential direction. The first protrusion 34 also has an inclined portion 34c that slopes from the upper portion 34a to the lower portion 34b. The upper portion 34a is located at the highest point of the first protrusion 34. The lower portion 34b is located lowermost than the other portions of the first protrusion 34. As shown in FIG. 1, a protrusion (second protrusion) 54 is also provided at the radial end of the lower end of the lower umbrella portion 50. The radial size of the lower umbrella portion 50 is the same as the radial size of the upper umbrella portion 32. The protrusion 54 goes around the outer circumferential surface of the lower umbrella portion 50, and the protrusion length of the protrusion 54 from the lower umbrella portion 50 in the circumferential direction is the same.

[0022] The covering portion 36 is provided below the upper umbrella portion 32. A first restricting portion 36a and second restricting portions 36b and 36c are provided on the outer peripheral surface of the covering portion 36. The first restricting portion 36a and the second restricting portions 36b and 36c all protrude radially outward from the outer peripheral surface of the covering portion 36. The first restricting portion 36a and the second restricting portions 36b and 36c are used to secure the mounting bracket (described later). A fixing portion 38 is fitted into the outer peripheral surface of the covering portion 36 from the lower end side. The fixing portion 38 is used to secure the lower umbrella portion 50, which functions as the umbrella member of the high-pressure cutout 100 (see also FIG. 1). The fixing portion 38 is an annular member made of rubber. Specifically, an annular slit cutout portion is formed in the fixing portion 38. The lower umbrella portion 50 is fixed to the covering portion 36 (upper cutout body 30) by fitting the upper end of the lower umbrella portion 50 into the slit notch. A pair of grooves 40 is provided at the lower end of the covering portion 36. The pair of grooves 40 are provided at positions symmetrical with respect to the axis of the covering portion 36. Each groove 40 is a T-shaped notch and is used to fix the lower cutout body 70.

[0023] As shown in FIGS. 3 and 4, an upper wire housing 31a is provided above the upper cutout body 30, with an inner diameter equal to that of the protrusion 31. A protrusion 42 protruding radially inward is provided on the wall surface of the upper wire housing 31a. Two protrusions 42 are provided on the wall surface of the upper wire housing 31a, and the protrusions 42, 42 are provided symmetrically with respect to the center of the upper wire housing 31a. The pair of protrusions 42 fit into a pair of recesses (not shown) provided on the outer peripheral surface of the lower end cylindrical portion of the upper mold cone 3. The fit between the pair of protrusions 42 and the pair of recesses prevents the upper wire from rotating relative to the upper cutout body 30 (high-voltage cutout 100). An inclined portion 46, whose inner diameter decreases upward, is provided on the upper part of the covering portion 36. A restricting step 45, whose inner diameter is smaller than the minimum diameter of the inclined portion 46, is provided above the inclined portion 46.

[0024] The inclined portion 46 is used to guide the insertion portion 74 (see FIG. 1 ) of the lower cutout body 70 (described later) to the center of the covering portion 36 when the insertion portion 74 is inserted into the covering portion 36. The restricting step 45 is used to prevent the insertion portion 74 from contacting the upper step 45 a of the covering portion 36. Specifically, the insertion portion 74 normally contacts the restricting step 45 but not the upper step 45 a. However, for example, if the length of the insertion portion 74 is longer than the design value due to a manufacturing error or the like, or if the length of the covering portion 36 is shorter than the design value, the tip of the insertion portion 74 contacts the restricting step 45, thereby preventing the insertion portion 74 from contacting the upper step 45 a of the covering portion 36. The upper wire accommodating portion 31 a and the space within the covering portion 36 are connected by a through hole (second through hole) 44. The second through hole 44 is used to fix the upper electrode 4.

[0025] The inner circumferential surface of the upper umbrella portion 32 is provided with downwardly extending folds 33. The lower ends of the folds 33 are located higher than the lower end (first protrusion 34) of the upper umbrella portion 32. Therefore, when the upper cutout body 30 is observed from the side, the folds 33 are not visible (see also FIG. 2). The provision of the folds 33 increases the creepage distance of the outer surface of the high-voltage cutout 100, improving the insulating performance of the high-voltage cutout 100. The inner circumferential surface of the lower umbrella portion 50 is provided with downwardly extending folds 50a. The lower ends of the folds 50a are located higher than the lower end of the lower umbrella portion 50. Therefore, when the upper cutout body 30 is observed from the side, the folds 50a are not visible. The provision of the folds 50a increases the creepage distance of the outer surface of the high-voltage cutout 100, improving the insulating performance of the high-voltage cutout 100.

[0026] As shown in FIG. 5 , the mounting bracket 90 has a portion (arc portion) that follows the outer periphery of the sheathed portion 36, and the straight portion at the tip end is fixed with a bolt 91. Typically, the bolt 91 is fastened to the portion (straight portion) that is away from the workpiece to which the high-voltage cutout 100 is attached, such as a utility pole. In the high-voltage cutout 100, the boundary portion (bent portion) between the arc portion and the straight portion at the tip end engages with the second restricting portion 36b, and the boundary portion (bent portion) between the arc portion and the straight portion on the workpiece side engages with the second restricting portion 36c. When the mounting bracket 90 is attached to the sheathed portion 36, each bent portion of the mounting bracket 90 engages with the second restricting portion 36b and the second restricting portion 36c, respectively, thereby restricting rotation of the mounting bracket 90 relative to the sheathed portion 36.

[0027] As is clear from FIG. 5 , in the high-pressure cutout 100, the upper portion 34a of the first protrusion 34 covers the straight portion of the mounting bracket 90. In other words, the lower portion 34b of the first protrusion 34 covers the arc portion of the mounting bracket 90. Rainwater adhering to the upper umbrella portion 32 flows over the surface of the upper umbrella portion 32 and reaches the first protrusion 34. Of the rainwater that reaches the first protrusion 34, the rainwater that reaches the upper portion 34a flows over the top surface of the inclined portion 34c and moves to the end of the lower portion 34b (the lowest position of the first protrusion 34). The rainwater then falls from the end of the lower portion 34b of the first protrusion 34. In other words, the rainwater adhering to the upper umbrella portion 32 falls from the end of the lower portion 34b of the first protrusion 34. Therefore, rainwater that falls from the upper umbrella portion 32 can be prevented from falling onto the mounting bracket 90 (the straight portion). As a result, flashover between the outer surface (upper umbrella portion 32) of the high voltage cutout 100 and the mounting bracket 90 can be suppressed.

[0028] Returning to FIG. 1 , the lower cutout body 70 will be briefly described. As shown in FIG. 1 , the lower cutout body 70 includes a large-diameter cylindrical portion 78 and a tubular insertion portion 74 that is smaller in diameter than the cylindrical portion 78 and extends upward from the cylindrical portion 78. The cylindrical portion 78 accommodates the lower electrode 12. The insertion portion 74 is inserted into the covering portion 36 of the upper cutout body 30. The fuse cylinder 8 and the arc-extinguishing cylinder 6 are also disposed within the insertion portion 74. The radial size of the cylindrical portion 78 is smaller than the radial size of the upper umbrella portion 32.

[0029] (Second Example) 6 and 7, a modified example of the high-pressure cutout 100 will be described. In the high-pressure cutout of this embodiment, the structure of the first protrusion 134 of the upper cutout body 130 is different from the structure of the first protrusion 34 of the upper cutout body 30 of the first embodiment. Therefore, in the following description, only the upper cutout body 130 will be described. Furthermore, for the upper cutout body 130, parts with substantially the same structure as the upper cutout body 30 will be given the same reference numerals as the upper cutout body 30, and descriptions thereof may be omitted.

[0030] The upper cutout body 130 includes an upper umbrella portion 132 and a covering portion 136. The upper umbrella portion 132 widens in diameter from top to bottom, and has a first protrusion 134 at the radial end of its lower end. The first protrusion 134 is formed at two locations on the outer circumferential surface of the upper umbrella portion 132, and has an inclined portion 134c that is inclined from the upper portion 134a to the lower portion 134b. The upper portion 134a and the lower portion 134b protrude radially outward from the upper umbrella portion 132 by the same length. The upper portion 134a is located at the highest position relative to the other portions of the first protrusion 134. The lower portion 134b is located at the lowest position relative to the other portions of the first protrusion 134. Furthermore, the two lower portions 134b are not connected to each other but are disconnected from each other. As a result, it can be said that the lower cutout body 130 is provided with two first protrusions 134.

[0031] As is clear from FIGS. 6 and 7 , in the upper cutout main body 130, the upper portion 134a of the first protrusion 134 also covers the straight portion of the mounting bracket 90. In other words, the lower portion 134b of the first protrusion 134 partially covers the arc portion of the mounting bracket 90. Rainwater adhering to the upper umbrella portion 132 falls from the end of the lower portion 134b of the first protrusion 134. More specifically, the rainwater adhering to the upper umbrella portion 132 flows over the surface of the upper umbrella portion 132 and reaches the first protrusion 134. Of the rainwater that reaches the first protrusion 134, the rainwater that reaches the upper portion 134a flows over the top surface of the inclined portion 134c and moves to the end of the lower portion 134b (the lowest position of the first protrusion 134). The rainwater then falls from the end of the lower portion 134b of the first protrusion 134. That is, rainwater adhering to the upper umbrella portion 132 falls from the end of the lower portion 134b of the first protrusion 134. Therefore, it is possible to prevent rainwater falling from the upper umbrella portion 132 from falling onto the mounting bracket 90 (straight portion). As a result, it is possible to prevent flashover between the outer surface of the upper umbrella portion 132 and the mounting bracket 90. Furthermore, because the two lower portions 134b are not connected, rainwater reliably falls from the end of the lower portions 134b, which makes it possible to prevent rainwater and contaminants from remaining on the upper surface of the lower portions 134b.

[0032] (Other variations) In the second embodiment, the radially outward protrusion lengths of the upper portion 134a and the lower portion 134b of the upper umbrella portion 132 are equal. However, the radially outward protrusion lengths of the upper portion 134a and the lower portion 134b may be different. For example, the radially outward protrusion length of the upper portion 134a may be longer than the radially outward protrusion length of the lower portion 134b. In this case, the area covered by the upper portion 134a over the straight portions of the mounting bracket 90 is increased, further preventing flashover between the outer surface of the upper umbrella portion 132 and the mounting bracket 90. Note that, in the upper umbrella portion 32 of the first embodiment, the radially outward protrusion length of the upper portion 34a may also be longer than the radially outward protrusion length of the lower portion 34b.

[0033] In the above embodiment, the protrusion 54 of the lower umbrella portion 50 surrounds the outer peripheral surface of the lower umbrella portion 50, and the protrusions 54 have the same circumferential length from the lower umbrella portion 50. However, the structure of the protrusion 54 of the lower umbrella portion 50 may be the same as the structure of the first protrusion 134 of the upper umbrella portion 132. That is, the protrusions 54 may be formed in two locations on the outer peripheral surface of the lower umbrella portion 50, with the lower portions being disconnected and not connected to each other. Furthermore, the radially outward protrusion length of the upper portion of the protrusion 54 may be longer than the radially outward protrusion length of the lower portion.

[0034] In the above embodiment, an example has been described in which the radial size of the upper umbrella portion 32, 132 and the radial size of the lower umbrella portion 50 are the same. However, the radial sizes of the upper umbrella portion 32, 132 and the lower umbrella portion 50 may be different. For example, the radial size of the lower umbrella portion 50 may be larger than the radial size of the upper umbrella portion 32, 132. The radial size of the lower umbrella portion 50 can also be changed as appropriate, as long as it is larger than the radial size of the cylindrical portion 78 of the lower cutout body 70.

[0035] Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. Furthermore, the technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives itself has technical utility. [Explanation of symbols]

[0036] 4:Top electrode 8: Fuse barrel 12: Lower electrode 30: Upper cutout body 32: Upper umbrella part 34:First protrusion 70: Lower cutout body 100: Cylindrical cutout

Claims

1. In a cylindrical cutout connected to a distribution line and high-voltage equipment wiring, an upper cutout body having an upper electrode therein for connection to both the power distribution line and the fuse barrel; a lower cutout body having a lower electrode therein that is connected to both the high-voltage equipment wiring and the fuse cylinder, the upper cutout body has an upper umbrella portion for increasing the creepage distance of the outer surface of the cylindrical cutout; A cylindrical cutout having a first protrusion protruding radially outward at a radial end of the upper umbrella portion.

2. the upper cutout body has a cylindrical covering portion that covers a portion of the lower cutout body; the covering portion is provided with a lower umbrella portion for increasing the creepage distance of the outer surface of the cylindrical cutout; 2. The cylindrical cutout according to claim 1, wherein a second protrusion protruding radially outward is provided at a radial end of the lower umbrella portion.

3. a circumferential portion of the first protruding portion is provided at a higher position than the other portion, Another part of the first protruding portion in the circumferential direction is provided at a lower position than the other part, 3. The cylindrical cutout of claim 1 or 2, wherein the first protrusion is angled from an upper position to a lower position.

4. the lower cylindrical cut body has a cylindrical portion that accommodates the lower electrode; 4. The cylindrical cutout according to claim 1, wherein the cylindrical portion has a radial size smaller than the radial size of the upper umbrella portion.

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