JP4634826B2 - Bushing for transformer with cut-out function and transformer with built-in cut-out fuse - Google Patents

Description

  The present invention relates to a transformer bushing having a cutout function and a transformer with a built-in cutout fuse formed by attaching the bushing for a transformer to a transformer tank.

  In the power distribution system, in order to simplify the configuration of the equipment to be mounted and to harmonize with the surrounding environment, as shown in Patent Document 1 and Patent Document 2, a bushing is attached to the side wall of the transformer tank, A pole transformer with a built-in cutout fuse has been developed in which a cutout fuse is removably accommodated in a bushing.

  As shown in FIG. 10, the transformer shown in Patent Document 1 is attached to a transformer tank 1 ′, a transformer body (not shown) housed in the transformer tank 1 ′, and the transformer tank 1 ′. And a transformer bushing 2 'having a cutout function. The transformer bushing 2 'with a cutout function is accommodated in the cannula 201', the rear end of which is attached to the transformer tank 1 'in a state where the front end is directed obliquely downward, and inside the front end of the cannula 201'. From the female lead-side contact 202 ', the female transformer-side contact 203' housed inside the rear end of the cannula 201 ', and the opening provided at the tip of the cannula 201'. The cutout fuse 204 ′ is inserted in the cannula in a state where it can be inserted and removed, and the arc extinguishing cylinder 205 ′ is disposed inside the cannula 201 ′.

  Cutout fuse 204 'is a cylindrical fuse container 206' containing a fusible body, and a lead side attached to one end and the other end of the fusible body respectively attached to the front end and rear end of the fuse container Surrounding the electrode 207 ′, the transformer side electrode 208 ′, the extinguishing rod 209 ′ having one end connected to the rear end of the fuse case 206 ′, and the portion adjacent to the lead side electrode 207 ′ on the front end side of the fuse case 206 ′ The arc-extinguishing tube 210 'is attached in this manner, and the lead-side electrode and transformer-side electrodes 207' and 208 'are brought into contact with the lead-side contact 202' and the transformer-side contact 203 ', respectively. The arc extinguishing cylinder 205 ′, the arc extinguishing rod 209 ′, and the arc extinguishing tube 210 ′ are made of a resin that generates arc extinguishing gas when heated by an arc, such as Duracon resin.

  A lead wire 3 'drawn from the outside is connected to the lead side contact 202', and a lead wire 4 'drawn from the primary side of the transformer body is connected to the transformer side contact 203'. The arc extinguishing cylinder 205 'is disposed in the space between the lead side contact 202' and the transformer side contact 203 'in the sleeve so that the cutout fuse 204' is pulled out from the sleeve 201 '. A slit is formed between the arc extinguishing rod 209 'and the arc extinguishing tube 210'.

  In this type of transformer, the lead-side contact 202 'and the transformer-side contact 203' are connected by inserting the cut-out fuse 204 'into the bushing sleeve 201', and the lead drawn from the outside is connected. The line 3 'and the primary side of the transformer body are electrically connected. Further, by pulling out the cut-out fuse 204 ′ from the sleeve 201 ′, the lead-side contact 202 ′ and the transformer-side contact 203 ′ in the sleeve are opened. When the cutout fuse 204 'is pulled out of the sleeve, the lead-side electrode 207' and the transformer-side electrode 208 'are contacted with the respective electrodes when they are separated from the lead-side contact 202' and the transformer-side contact 203 ', respectively. An arc is generated between An arc generated between the lead-side electrode 207 'and the lead-side contact 202' and an arc generated between the transformer-side electrode 208 'and the transformer-side contact 203' are caused by the arc-extinguishing tube 205 'and the arc-extinguishing tube. The slit formed between 210 ′ and the arc formed between the arc-extinguishing cylinder 205 ′ and the arc-extinguishing rod 209 ′ are drawn and extinguished.

The transformer bushing disclosed in Patent Document 2 is also configured in the same manner as described above.
JP 2004-192998 A JP 2001-93741 A

  When the bushings for transformers with a cut-out function shown in Patent Document 1 and Patent Document 2 are used outdoors, it is necessary to replace the fuse even in rainy weather in an emergency. If the fuse is replaced in the rain, water may enter from the opening at the tip of the cannula, or when the cutout fuse is inserted into the cannula, water droplets attached to the outer surface may enter the bushing. There is. When water enters the bushing in this manner, the water evaporates when the temperature in the cannula rises due to heat generation by energization or solar heat irradiation, and water vapor condenses when the temperature in the cannula falls at night. If condensation occurs in the bushing, the outer peripheral surface of the fuse container and the inner peripheral surface and outer peripheral surface of the arc extinguishing cylinder get wet and the dielectric strength in the bushing is reduced. When fusing, a high voltage is applied between the transformer side contact and the lead side contact, and leakage current flows through the outer peripheral surface of the fuse container and the inner peripheral surface and outer peripheral surface of the arc extinguishing cylinder. There was a problem that the fuse container and the arc extinguishing cylinder were carbonized and deteriorated due to the heat generated by the above. When the fuse container and the arc extinguishing cylinder are carbonized and deteriorated, the dielectric strength between the transformer side contact and the lead side contact is remarkably lowered, and thus a flashover may occur between the two contacts, which may lead to an accident.

  If the water that has entered the bushing can be discharged to the outside at an early stage, the above problems can be avoided. However, in the conventional bushing for a transformer with a cutout function, the arc-extinguishing tube and the sleeve There are several stepped parts that have a surface perpendicular to the axial direction of the sleeve, and these stepped parts act to keep moisture in the bushing by blocking the moisture that has condensed. The state in which the cycle of moisture evaporation and condensation continues for a long period of time, and it is inevitable that the probability that each part in the bushing will be wet while the fuse is blown out is increased to some extent. For example, in the example shown in FIG. 10, there are stepped portions d1 and d2 in the portions indicated by circles Z1 and Z2 in the drawing, and there is a possibility that water W may accumulate at these stepped portions.

  The object of the present invention is to make the structure in which moisture does not easily accumulate in the bushing, thereby reducing the probability that each part in the bushing will be wet while the fuse is in a blown state, thereby improving safety. An object of the present invention is to provide a bushing for a transformer with an out function and a transformer with a built-in cutout fuse in which the bushing is attached to a transformer tank.

The present invention is directed to a transformer bushing having a cut-out function in which a cut-out fuse is detachably accommodated in a sleeve having a rear end portion attached to a transformer tank with a front end directed obliquely downward.
In the present invention, when the rear end portion of the cannula is attached to the transformer tank, the drainage that causes water existing in the cannula to flow down to the front end side of the cannula along the inner peripheral surface of the cannula. A passage is provided over the entire length in the axial direction of the cannula, and a drain outlet for discharging the water flowing down along the drainage passage to the outside is provided at the tip of the cannula.

  As described above, a drainage passage is provided over the entire length in the axial direction of the cannula along the inner periphery of the cannula and flows along the inner peripheral surface of the cannula, along the drainage passage. If a drain outlet for discharging the water flowing down to the outside is provided at the tip of the sleeve, the water that has entered the bushing and the water that has condensed in the bushing move downward in the bushing and reach the drainage passage. It flows down along the drainage passage and is discharged outside through the drainage port. Since most of the water that has entered the bushing is quickly discharged to the outside in this manner, the inside of the bushing quickly returns to a dry state due to heat generated by energization or a temperature increase due to solar heat irradiation. Therefore, the state in which the dielectric strength in the bushing is reduced due to the presence of water is prevented from continuing for a long time, and the probability that the dielectric strength in the bushing is reduced while the fuse is blown is reduced. It is possible to prevent the extinguishing cylinder and the fuse container from deteriorating due to leakage current flowing through the inner and outer peripheral surfaces of the extinguishing cylinder and the outer peripheral surface of the fuse container.

  Usually, a transformer bushing having a cut-out function has a sleeve having a rear end attached to the transformer tank with the tip directed obliquely downward, and a lead-side contact accommodated inside the tip of the sleeve. A transformer-side contact accommodated inside the rear end of the sleeve, a cylindrical fuse container containing a fusible body, and one end of the fusible body attached to the front end and the rear end of the fuse container, respectively A lead-side electrode and a transformer-side electrode connected to the other end, respectively. The lead-side electrode and the transformer-side electrode are connected to the lead-side contact and the transformer-side electrode, respectively. A cutout fuse that is brought into contact with the transformer side contact and a cutout fuse that is disposed in a space between the lead side contact and the transformer side contact in the sleeve. And an extinguishing cylinder that forms a slit between the arc extinguishing rod of the cutout fuse and the arc extinguishing tube when being pulled out from the lead, and a lead wire that is drawn from the outside is connected to the lead side contact, The primary side of the transformer is connected to the side contact. When the transformer bushing is configured as described above, in a preferred aspect of the present invention, between the cannula and the lead side contact, between the cannula and the extinguishing cylinder, and between the cannula and the transformer side contact, A gap is formed between the sleeve and the lead side contact, the gap between the sleeve and the extinguishing cylinder, and the gap between the sleeve and the transformer side contact. When the rear end of the tube is attached to the transformer tank, a drainage passage for allowing water existing in the cannula to flow along the inner peripheral surface of the cannula to the front end side of the cannula is an axis of the cannula It is formed over the entire length in the direction. Further, a drainage port having one end communicating with the drainage passage and the other end opened downward is provided at the distal end portion of the cannula.

  In another preferable aspect of the bushing according to the present invention, the arc extinguishing cylinder includes a lead side arc extinguishing cylinder having one end connected to the lead side contact, and a transformer side arc extinguishing cylinder having one end connected to the transformer side contact. And divided into two.

  As described above, when the extinguishing cylinder is divided into two, the lead surface distance formed through the outer peripheral surface and the inner peripheral surface of the extinguishing cylinder can be cut off, so that the lead between the transformer side contact and the lead side contact The surface insulation distance can be increased to increase the dielectric strength, and leakage current can be prevented from flowing between the contacts when water is present in the bushing.

In a more specific aspect of the present invention, a transformer bushing with a cut-out function is configured as follows.
An end cap having an end plate and a fuse insertion opening is attached so as to close the rear end portion and the distal end portion of the cannula, respectively, and the contact support cylinder is disposed concentrically with the cannula inside the distal end portion of the cannula One end of the body is connected to the end cap.
The lead-side contact includes a tubular lead-side shield conductor inserted into the contact support cylinder and supported by the cylinder, and a contact member disposed inside the lead-side shield conductor and in contact with the lead-side electrode. It has.
The transformer-side contact is formed in a cylindrical shape so as to receive the rear end portion of the cutout fuse, one end is supported by the end plate, and the other end is opened to the lead-side contact side, and the tubular transformer-side shield conductor, A contact member disposed on the inner side of the other end side of the transformer-side shield conductor and in contact with the transformer-side electrode.
The arc-extinguishing tube is inserted and supported at one end inside the lead-side shield conductor, and the other end is connected to the other end of the transformer-side shield conductor. It consists of a transformer-side extinguisher that is connected via a member and has the other end opened to the lead-side contact side.
The connecting member is formed of a ring-shaped member that surrounds and engages the other end of the transformer-side shield conductor and one end of the transformer-side extinguishing cylinder, and the ring-shaped member is an inner periphery of the sleeve. A contact portion between the conductive member and the transformer-side extinguishing cylinder is supported by the sleeve by contacting the surface.
A ring-shaped support member that surrounds a portion near the other end of the transformer-side extinguishing cylinder is provided, and the other end of the transformer-side extinguishing cylinder is brought into contact with the inner peripheral surface of the cannula. The close part is supported against the cannula.
Between the cannula and the lead-side contact, between the cannula and the lead-side shield conductor, between the cannula and the lead-side extinguisher, between the cannula and the transformer-side extinguishing cylinder, and between the cannula and the transformer Clearances are formed between the outer shield shield conductors, and these gaps allow water existing in the cannula to flow inside the cannula when the rear end of the cannula is attached to the transformer tank. A drainage passage that flows down to the distal end side of the cannula along the peripheral surface is formed over the entire length in the axial direction of the cannula, and a drainage port having one end communicating with the drainage passage and the other end opened to the outside is the cannula. Is provided at the tip.
The connecting member and the supporting member have a gap for allowing water flowing through the drainage passage to pass therethrough.

The present invention also provides a transformer tank, a transformer main body housed in the transformer tank, a sleeve having a rear end attached to the transformer tank with the tip directed obliquely downward, It is applied to a transformer with a built-in cutout fuse having a cutout fuse housed in a removable manner.
In the present invention, when the rear end portion of the cannula is attached to the transformer tank, the drainage that causes water existing in the cannula to flow down to the front end side of the cannula along the inner peripheral surface of the cannula. A passage is provided over the entire length in the axial direction of the cannula, and a drain outlet for discharging the water flowing down along the drainage passage to the outside is provided at the tip of the cannula.

Usually, a transformer with a built-in cutout fuse includes a transformer tank, a transformer main body accommodated in the transformer tank, and a sleeve having a rear end attached to the transformer tank with the front end facing obliquely downward. A lead-side contact housed inside the front end of the cannula, a transformer-side contact housed inside the rear end of the cannula and connected to the primary side of the transformer body, a fusible body And a lead-side electrode and a transformer-side electrode attached to one end and the other end of the fusible body, respectively, attached to the front end portion and the rear end portion of the fuse vessel. A cutout fuse in which the lead-side electrode and the transformer-side electrode are brought into contact with the lead-side contact and the transformer-side contact, respectively, from the distal end of the tube so as to be removably inserted into the sleeve, and a lead-side contact in the sleeve And an extinguishing cylinder that forms a slit between the cut-out fuse when the cut-out fuse is pulled out of the sleeve, and is drawn from the outside. Lead wire is connected to lead side contact.
When the transformer is configured as described above, in a preferred aspect of the present invention, between the sleeve and the lead side contact, between the sleeve and the extinguishing cylinder, and between the sleeve and the transformer side contact. A gap communicating with each other is formed, and a gap between the sleeve and the lead-side contact, a gap between the sleeve and the extinguishing cylinder, and a gap between the sleeve and the transformer-side contact, A drainage passage is formed over the entire length in the axial direction of the cannula to allow water existing in the cannula to flow along the inner peripheral surface of the cannula to the distal end side of the cannula, and one end communicates with the lowermost end of the drainage passage. A drain outlet having the other end opened downward is provided at the tip of the cannula.

  Also in this case, the arc-extinguishing cylinder is divided into two parts, a lead-side arc-extinguishing cylinder whose one end is connected to the lead-side contact and a transformer-side arc-extinguishing cylinder whose one end is connected to the transformer-side contact. preferable.

In a more specific aspect of the present invention, the transformer is configured as follows.
An end cap having an end plate and a fuse insertion opening is attached so as to close the rear end portion and the distal end portion of the cannula, respectively, and the contact support cylinder is disposed concentrically with the cannula inside the distal end portion of the cannula One end of the body is connected to the end cap.
The lead-side contact includes a tubular lead-side shield conductor inserted into the contact support cylinder and supported by the cylinder, and a contact member disposed inside the lead-side shield conductor and in contact with the lead-side electrode. I have.
The transformer side contact is formed in a cylindrical shape so as to receive the rear end portion of the cutout fuse, one end is supported by the end plate, and the other end is opened to the lead side contact side, and the transformer side shield conductor A contact member disposed on the inner side of the other end side of the transformer-side shield conductor and in contact with the transformer-side electrode.
A rod-shaped terminal conductor connected to the lead wire drawn out from the primary side of the transformer is connected to the transformer-side shield conductor, and the terminal conductor is led out through the end plate.
A terminal rod having a lead wire connecting portion for connecting a lead wire at one end passes through the side wall near the tip of the cannula and is introduced into the cannula, and the other end of the terminal rod is connected to the lead-side shield conductor. Yes.
The extinguishing cylinder is inserted and supported at one end inside the lead-side shield conductor, and the other end is connected to the other end of the transformer-side shield member. It consists of a transformer-side extinguisher which is connected via a member and has the other end opened to the lead-side contact side.
The connecting member is formed of a ring-shaped member that surrounds and engages the other end of the transformer-side shield conductor and one end of the transformer-side extinguishing cylinder, and the ring-shaped member is an inner periphery of the sleeve. A contact portion between the transformer-side shield conductor and the transformer-side extinguishing cylinder is supported by the sleeve by contacting the surface.
A ring-shaped support member is provided to surround a portion near the other end of the transformer-side extinguishing cylinder, and the support member is brought into contact with the inner peripheral surface of the sleeve so that it is closer to the other end of the transformer-side extinguishing cylinder. Is supported against the cannula.
There are gaps between the sleeve and the contact support cylinder, between the sleeve and the lead-side extinguishing cylinder, between the cannula and the transformer-side extinguishing cylinder, and between the cannula and the transformer-side shield conductor. These gaps allow water present in the cannula to flow along the inner peripheral surface of the cannula when the rear end of the cannula is attached to the transformer tank. A drainage passage that flows down to the distal end side is formed over the entire length of the cannula in the axial direction, and a drainage port having one end communicating with the lowermost end of the drainage passage and the other end opened to the outside is provided at the distal end portion of the cannula It has been.
The connecting member and the supporting member are provided so as to form a gap for allowing the water flowing through the drainage passage to pass therethrough.

  As described above, according to the present invention, the drainage passage is provided over the entire length in the axial direction of the cannula so that the water existing in the cannula flows down to the distal end side of the cannula along the inner peripheral surface of the cannula. In addition, a drain outlet is provided at the tip of the cannula to discharge the water that has flowed down along the drainage passage to the outside, so that water that has entered the bushing and water condensed in the bushing can be quickly collected through the drainage passage. Even if water enters the bushing when exchanging the cutout fuse in the rain, the water is quickly discharged to the outside of the sleeve and the bushing is caused by the presence of water. It is possible to prevent the state in which the dielectric strength is lowered from continuing. Therefore, the state where the dielectric strength in the bushing is reduced due to the presence of water is prevented from continuing for a long time, and the probability that the dielectric strength in the bushing is reduced while the fuse is blown is reduced. It is possible to prevent the extinguishing cylinder and the fuse container from deteriorating due to leakage current flowing through the inner and outer peripheral surfaces of the extinguishing cylinder and the outer peripheral surface of the fuse container.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a configuration of a main part of a preferred embodiment of a transformer with a built-in cutout fuse according to the present invention. In FIG. 1, 1 is a transformer tank installed on a pillar. In the transformer tank 1, a transformer body (not shown) is accommodated together with insulating oil. The transformer tank 1 includes a nozzle 101 at the upper part of the side wall, and a bushing 2 with a cutout function is attached to the nozzle 101. The nozzle 101 is made of a tubular member having a flange plate 102 attached to the tip thereof, and is arranged with the tip thereof directed obliquely downward, and is welded to the side wall of the transformer tank 1.

  The transformer bushing 2 with a cutout function includes a cannula 201, a female lead-side contact 202 accommodated inside the tip of the cannula 201, and a female accommodated inside the rear end of the cannula 201. Transformer-side contact 203, a cut-out fuse 204 inserted in a state where it can be inserted into and removed from the opening of the sleeve 201, and a lead side disposed inside the sleeve 201 The arc-extinguishing cylinder and the transformer-side arc-extinguishing cylinders 205A and 205B are configured.

  The cannula 201 is composed of an inner insulating tube 201a and an outer insulating tube 201b with a cap joined to the outer periphery of the insulating tube, and a flange 201c is attached to a portion near the rear end. The cannula 201 is inserted into the nozzle 101 through the hole on the inner peripheral side of the flange plate 102 of the nozzle 101 and the flange 201c is bolted to the flange plate 102. It is attached to the transformer tank 1 with its tip directed obliquely downward.

  An end plate 220 and an end cap 221 (see FIG. 4) are attached so as to close the rear end portion and the front end portion of the cannula 201, and the end cap 221 is formed with a fuse insertion port 221a through which the cutout fuse 204 passes. ing. Further, one end of a contact support cylinder 222 arranged concentrically with the sleeve 201 is bolted to the end cap 221. The contact support cylinder 222 is formed of a resin that generates an arc extinguishing gas when heated (duracon resin in this embodiment).

  As shown in FIGS. 5A and 5B, the contact support cylindrical body 222 has a cross-sectional shape in which four corners of a square are rounded. It is configured to be inscribed. The support cylinder 222 is attached so that one side surface thereof faces the lower part of the inner peripheral surface of the cannula 201 (the lower part when attached to the transformer tank). A gap G1 is formed between the inner peripheral surface and the lower portion of the inner peripheral surface. On the inner peripheral surface of the contact support cylindrical body 222, a step portion 222a for positioning the tip of the lead side contact 202 in contact is formed.

  The lead-side contact 202 includes a tubular lead-side shield conductor 202A having a flange 202a1 at the rear end as shown in FIG. 6B, a contact member 202B shown in FIG. 6A, and FIG. The shield ring 202C shown in FIG. The contact member 202B is formed in a tulip shape by an annular base 202b1 provided on the rear end side and a large number of contact pieces 202b2 protruding in the axial direction from the tip of the base 202b1, and the tip of the contact piece is The lead-side shield conductor 202A is inserted into the lead-side shield conductor 202A in a state directed toward the tip side. The shield ring 202C is made of a ring-shaped member having a flange portion 202c1 formed at the tip, and is inserted into the shield conductor from the tip side of the lead-side shield conductor 202A to form the contact piece 202b2 of the contact member 202B. The tip is contacted from the inside. The shield ring 202C is provided for the purpose of relaxing the electric field near the tip of the contact piece of the contact member and for the purpose of guiding the fuse inserted into the sleeve 201.

  The lead side contact 202 has the tip (shield ring 202C) facing the end cap 221 side, and the other side of the contact support cylinder 222 until the shield ring 202C contacts the inner peripheral step 222a of the contact support cylinder 222. The flange 202b3 provided at the rear end of the contact member 202B and the flange 202a1 of the lead side shield conductor 202A are bolted to the other end of the contact support cylinder 222, inserted into the contact support cylinder from the end side, The lead side contact 202 is fastened to the contact support cylinder 222.

  A terminal bar 223 having a lead wire connection part for connecting the lead wire 3 at one end passes through the side wall near the tip of the cannula 201 and is introduced into the cannula, and the other end of the terminal bar 223 is the lead-side shield conductor. It is connected to the flange 202a1 of 202A.

  As shown in FIG. 4, the end cap 221 has a recess (relief) 221 b in the lowermost portion with the bushing attached to the transformer tank, and the end cap 221 contacts the end cap 221 by this recess 221 b. A gap Ga that opens to the outside is formed between one end of the support cylinder 222.

  As shown in FIG. 7A, the lead-side extinguishing cylinder 205A integrally includes a thick part 205a2 having a flange part 205a1 at one end and a thin part 205a3 protruding in the axial direction from one end of the thick part 205a2. As shown in FIGS. 7B and 7C, a contact-side extinguishing cylinder 205A1 made of a cylindrical body, a rectangular cylinder 205a4 having a regular octagonal cross section as shown in FIGS. 7B and 7C, and one end of the rectangular cylinder 205a4 are formed. And the end cap side extinguishing cylinder 205A2 integrally having the thin cylindrical portion 205a5. The contact-side extinguishing cylinder 205A1 is disposed with its thin-walled part 205a3 inserted inside the lead-side contact 202, and the collar part 205a1 is fastened together with the collar part 202a1 of the shield conductor 202A of the lead-side contact to contact-cylinder It is fixed to the body 222. Further, the end cap side extinguishing cylinder 205A2 is positioned closer to the end cap than the lead side contact 202, and is fitted to the inner periphery of the contact support cylinder 222. Since the outer periphery of the rectangular tube portion 205a4 of the end cab side extinguishing cylinder 205A2 has a regular octagonal cross section, water is externally provided between the outer peripheral surface of the rectangular tube portion 205a4 and the inner peripheral surface of the contact support cylindrical body 222. A gap Gb for discharging is formed.

  As shown in FIG. 2, the cut-out fuse 204 includes a cylindrical fuse container 206 containing a fusible body, and one end of the fusible body and the other attached to the front end and the rear end of the fuse container. Adjacent to the lead-side electrode 207 and the transformer-side electrode 208 respectively connected to the ends, the extinguishing rod 209 having one end connected to the rear end of the fuse container 206, and the lead-side electrode 207 on the front end side of the fuse container 206 And an arc-extinguishing tube 210 attached to surround the portion. In the illustrated example, one end of a fusible body is connected to a cap-shaped terminal fitting 211 attached to the tip of the fuse container 207, and a lead-side electrode 207 formed in a cylindrical shape is bolted to the terminal fitting 211. . Further, a cap-shaped terminal fitting attached to the rear end portion of the fuse container 206 is used as the transformer-side electrode 208. The arc-extinguishing tube 210 is formed of a resin that generates arc-extinguishing gas when heated (duracon resin in this example), and the tip of the fuse container 206 is accommodated inside the terminal fitting 211. It is attached to cover the vicinity. An insulating operation rod 212 is attached to the end of the lead side electrode 207 opposite to the fuse container, and a fusing display device that operates when the fuse is blown to perform fusing display is accommodated inside the insulating operation rod. Yes. The fusing display device includes, for example, a mechanism that causes a needle to protrude from the tip of the fuse container 206 when the fuse is blown, and a display mechanism that causes a marker to protrude from the tip of the insulating operation rod 212 in conjunction with the needle. The

  The arc-extinguishing bar 209 is made of the same resin as the arc-extinguishing tube 210 (Duracon resin in this example), and is attached by being screwed to an attachment screw 213 attached to the rear end portion of the fuse container 206. At the end of the arc extinguishing rod 209, a grip portion 209a is formed that is gripped and gripped by a grip spring 225 (see FIG. 1) provided in the sleeve when the fuse is inserted into the sleeve 201. .

  As shown in FIG. 3C, the transformer-side contact 203 is formed in a cylindrical shape so as to receive the rear end portion of the cutout fuse attached to the fuse 204, and one end is supported by the end plate 220. A transformer-side shield conductor 203A having the other end opened to the lead-side contact side, a contact member 203B configured as shown in FIG. 3A and disposed in the transformer-side shield conductor 203A, and FIG. ) And a shield ring 203C formed in a ring shape and inserted into the transformer side shield conductor 203A.

  More specifically, the transformer side shield conductor 203A is formed of a cylindrical body having an open end, and a rod-shaped terminal conductor 224 is connected to the outer surface of the bottom 203a1. The contact member 203B has a structure in which a large number of contact pieces 203b2 protrude from the open end of the bottomed cylindrical base 203b1, and the lead-side shield conductor 203A with the base 203b1 facing the transformer side. Has been inserted inside. The shield ring 203C is inserted into the transformer-side shield conductor 203A through the opening, and is in contact with the tip of the contact piece of the contact member 203B from the inside. A gripping spring 225 (see FIG. 1) that grips the tip of the fuse cylinder is disposed inside the base 203b1 of the contact member 203B, and the gripping spring 225 and the bottom of the contact member 203B are fastened together by a bolt to shield the transformer side shield. It is fastened to the bottom 203a1 of the conductor 203A.

  The bottom 203a1 of the transformer side shield conductor 203A is in contact with the end plate 220 that closes the rear end of the cannula 201, and the terminal conductor 224 fixed to the outer surface of the bottom 203a1 passes through the axial center of the end plate 220. Are led out to the outside (in the transformer tank). A nut 226 is screwed into a screw portion provided on the outer periphery of the terminal conductor 224 led out to the outside, and the terminal conductor 224 is fastened to the end plate 220, so that the transformer side shield conductor 203A has the other end. It is supported with respect to the cannula 201 in a state opened to the lead side contact side. Connected to the terminal conductor 224 is a lead wire 4 drawn from the primary side of a transformer body (not shown) housed in the transformer tank 1.

  As shown in FIG. 3 (D), the transformer-side extinguishing cylinder 205B is formed of a cylindrical body having a tapered inner periphery from the intermediate part to the tip part, and is provided at the rear end part. An annular protrusion 205b2 is formed on the outer periphery of the neck portion 205b1. An annular groove 205b3 is formed on the outer periphery near the tip of the transformer-side extinguishing cylinder 205B. The transformer-side extinguishing cylinder 205B is arranged with its neck 205b1 inserted inside the other end of the transformer-side shield conductor 203A, and the protrusion 205b2 at the rear end of the transformer-side extinguishing cylinder 205B is transformed. The projection 205b2 and the collar portion 203a2 are in contact with each other via a coupling member 230 shown in FIGS. 8A and 8B, and abutted against the collar portion 203a2 provided at the tip of the vessel-side shield conductor 203A. Thus, the transformer-side extinguishing cylinder 205B is connected to the transformer-side shield conductor 203A.

  The illustrated connecting member 230 has a shape in which the cross-sectional contour shape is rounded at four corners of a square, and the transformer-side shield conductor 203A and the transformer-side arc extinguishing cylinder 205B are connected to each other. A ring-shaped member that can surround the portion is divided into two halves 230A and 230B formed along a plane including the axis, and the transformer-side shield is provided on the inner periphery of the halves 230A and 230B. A recess 230a is formed in which the flange 203a2 of the conductor 203A and the protrusion 205b2 of the transformer-side extinguishing cylinder 205 are fitted. When connecting the transformer-side arc-extinguishing cylinder and the transformer-side shield cylinder with the connecting member 230, the projection 205b2 of the transformer-side arc-extinguishing cylinder 205B is provided at the tip of the transformer-side shield conductor 203A. In a state of being in contact with 203a2, the halves 230A and 230B are fitted to the protrusion 205b2 and the collar 203a2, and the halves are abutted. The halves 230A and 230B are formed so as to form a gap g (see FIG. 8A) for allowing water to pass between the halves 230A and 230B. Further, in a state where the connecting member 230 is attached to the transformer-side arc-extinguishing cylinder and the transformer-side shield conductor, the maximum diameter portion (corner portion of the contour shape) of the connecting member 230 is in contact with the inner peripheral surface of the cannula 201. The maximum diameter of the connecting member 230 is set, and the connecting portion between the transformer-side arc extinguishing cylinder and the transformer-side shield conductor is connected to the sleeve by the engagement between the connecting member 230 and the inner peripheral surface of the sleeve 201. It has come to be supported. In the illustrated example, a water drain hole 230b (see FIG. 8B) is provided through the portion corresponding to the bottom of the recess 230a in order to drain the water that has entered the recess 230a of the connecting member 230.

  Further, a support member 231 shown in FIGS. 9A and 9B is attached to an annular groove 205b3 formed on the outer periphery of the transformer-side extinguishing cylinder 205B near the tip, and the transformer is used by the support member 231. The vicinity of the tip of the side arc extinguishing cylinder 205B is supported with respect to the cannula 201. The support member 231 is composed of halves 231A and 231B having the same structure as the halves 230A and 230B constituting the connecting member 230 except that there is no recess on the inner periphery, and these halves are fitted into the groove 205b3. They are attached to the transformer-side arc-extinguishing cylinder 205B by matching them together. The maximum diameter of the support member 231 is set so that the maximum diameter portion of the support member 231 contacts the inner peripheral surface of the cannula 201 with the support member 231 attached to the transformer-side arc-extinguishing cylinder 205B. The half portions 231A and 231B are formed so that a gap g (see FIG. 9A) for allowing water to pass between the two portions when they are fitted and abutted with the groove portion 205b3 of the transformer-side arc extinguishing cylinder is formed. It has been.

  In order to make the inner peripheral surface of the cannula 201 difficult to wet with water, a coating agent made of a water repellent material such as a fluororesin is applied to the inner peripheral surface of the cannula 201. Since the duracon resin constituting the arc extinguishing cylinders 205A and 205B originally has water repellency, it is not necessary to apply a coating agent made of a water repellent material.

  In the bushing of this embodiment, between the cannula 201 and the contact support conductor 222, between the cannula 201 and the lead side contact 202, between the cannula 201 and the lead side extinguishing cylinder 205A, Gaps G1, G2, G3, G4, and G5 are formed between the transformer-side extinguishing cylinder 205B and between the cannula 201 and the transformer-side shield conductor 203A, respectively, and these gaps G1 to G5 allow When the rear end portion of the pipe 201 is attached to the transformer tank, the water drainage passage 233 that causes water existing in the cannula 201 to flow along the inner peripheral surface of the cannula 201 to the front end side of the cannula. Is formed over the entire length of the sleeve in the axial direction. The connecting member 230 and the support member 231 are disposed in the middle of the drainage passage. However, since these members have a gap g for allowing water to pass therethrough, the drainage passage 233 is divided in the middle. Never happen.

  Further, in the bushing of the present embodiment, the bushing is inclined obliquely downward by the gap Ga formed between the end cap 221 and the tip of the cannula 201 by the recess 221b inside the end cap 221 at the tip of the cannula 201. A drainage port 234 having one end communicating with the lowermost end of the drainage passage 233 in an inclined state and attached to the transformer tank and having the other end opened downward is formed.

  The lead wire 3 drawn from the outside is connected to the lead wire connecting portion at one end of the terminal rod 223 connected to the lead side contact 202, and the primary side of the transformer body is connected to the terminal conductor 224 connected to the transformer side contact 203. The lead wire 4 led out from is connected.

  The cutout fuse 204 is inserted into the bushing 2 from the fuse insertion port 221a provided in the end cap 221 of the sleeve 201 of the bushing 2 with its rear end directed to the transformer tank 1 side. The extinguishing rod 209 provided on the side is inserted into the transformer-side contact 203, and the lead-side electrode 207 and the transformer-side electrode 208 are brought into contact with the lead-side contact 202 and the transformer-side contact 203, respectively. As a result, the cut-out fuse is turned on. In order to securely hold the cutout fuse in the inserted state, a gripping portion 209a provided on the arc extinguishing rod of the cutout fuse is gripped by a gripping spring 225 fixed to the inside of the transformer side shield conductor 203A. FIG. 1 shows a state in which the cutout fuse 204 is inserted in this way.

  When the cutout fuse 204 that is not blown is removed from the bushing 2, the lead side electrode 207 and the transformer side electrode 203 of the cutout fuse 204 are respectively connected to the lead side contact 202 and the transformer side contact 203 of the bushing. In the transformer of this embodiment, the arc-extinguishing tube 210 and the arc-extinguishing bar 209 and the arc-extinguishing cylinders 205A and 295B are heated by the arc heat, and the arc-extinguishing property is thereby removed. This gas is generated and the arc is cooled by this gas so that the arc is extinguished.

  As described above, the drainage passage 233 is provided over the entire length in the axial direction of the cannula so that the water existing in the cannula 201 flows down to the distal end side of the cannula along the lower portion of the inner peripheral surface of the cannula. If a drain outlet 234 for discharging the water flowing down along the drain passage 233 to the outside is provided at the tip of the cannula, the water that has entered the bushing and the water condensed in the bushing can be quickly collected through the drain passage. Can be discharged to the outside. Therefore, when water enters the bushing, such as when exchanging the cut-out fuse in the rain, the water is discharged to the outside of the sleeve early, and the insulation strength in the bushing decreases due to the presence of water. It is possible to prevent the state from continuing for a long time, reducing the probability that the dielectric strength in the bushing will be reduced while the fuse is blown, and the inner and outer peripheral surfaces of the extinguishing cylinder The possibility of deterioration of the extinguishing cylinder and the fuse container due to leakage current flowing through the outer peripheral surface of the fuse container can be reduced.

  As described above, when the arc-extinguishing cylinder is divided into the lead-side arc-extinguishing cylinder 205A and the transformer-side arc-extinguishing cylinder 205B, the lead surface distance formed through the outer peripheral surface and the inner peripheral surface of the arc-extinguishing cylinder is reduced to two. Since it can be cut off, it is possible to increase the insulation strength by increasing the lead surface insulation distance between the transformer side contact 202 and the lead side contact 203, and when water is present in the bushing, it leaks through both the contacts. Current can be prevented from flowing.

It is sectional drawing which showed the structure of the principal part of embodiment of the cutout fuse built-in type transformer concerning this invention. It is the front view which showed the cutout fuse used by the same embodiment partially in cross section. (A) And (B) is a front view of the contact member which comprises the transformer side contact used by the embodiment, respectively, and sectional drawing of a shield ring. Moreover, (C) is sectional drawing of the transformer side shield conductor which comprises the transformer side contact used by the embodiment, (D) is sectional drawing of the transformer side arc-extinguishing cylinder connected with the shield conductor. It is sectional drawing of the end cap used by embodiment of this invention. (A) And (B) is the side view and front view of a contact support cylinder which are used by embodiment of this invention, respectively. (A) thru | or (C) showed the component of the transformer side contact used by embodiment of this invention, (A), (B) and (C) are the front views of a contact member, respectively, and a lead side shield It is sectional drawing of a conductor, and sectional drawing of a shield ring. (A) thru | or (C) showed the component of the lead side arc-extinguishing cylinder used by embodiment of this invention, (A), (B) and (C) are sectional drawings of a contact side arc-extinguishing cylinder, respectively. They are sectional drawing of an end cap side extinguishing cylinder, and a side view of an end cap side arc extinguishing cylinder. (A) is a front view of the connection member used by embodiment of this invention, (B) is an AA arrow directional view of (A). (A) is a front view of the supporting member used by embodiment of this invention, (B) is a BB arrow directional view of (A). It is sectional drawing which showed the structure of the principal part of the conventional cutout fuse built-in type transformer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transformer tank 2 Bushing with cutout function 3 Lead wire 4 Lead wire from primary side of transformer main body 201 Tubular tube 202 Lead side contact 203 Transformer side contact 204 Cutout fuse 205A Lead side arc extinguishing cylinder 205B Transformer Side arc-extinguishing tube 233 Drain passage 234 Drain outlet

Claims (8)

A cannula having a rear end attached to the transformer tank with the front end directed obliquely downward, a lead-side contact accommodated inside the front end of the cannula, and an inner side of the rear end of the cannula The accommodated transformer side contact, the cylindrical fuse container containing the fusible body, and the lead side attached to the one end and the other end of the fusible body respectively attached to the front end and the rear end of the fuse container An electrode and a transformer side electrode, and inserted into the cannula from the tip of the cannula so that the lead side electrode and the transformer side electrode are in contact with the lead side contact and the transformer side contact, respectively. The cutout fuse is disposed in a space between the lead-side contact and the transformer-side contact in the sleeve, and the cutout fuse is pulled out from the sleeve A lead wire drawn from the outside is connected to the lead side contact, and a primary side of the transformer is connected to the transformer side contact. In transformer bushings with cutout function to be connected,
Between the cannula and the lead side contact, between the cannula and the extinguishing cylinder and between the cannula and the transformer side contact, a gap is formed to communicate with each other. A drainage passage for allowing water existing in the cannula to flow down to the front end side of the cannula along the inner peripheral surface of the cannula when the rear end of the cannula is attached to the transformer tank. Is formed over the entire length of the sleeve in the axial direction,
A drainage port having one end communicating with the drainage passage and the other end opening downward;
Bushing for transformer with cut-out function . The arc-extinguishing cylinder is divided into two parts, a lead-side arc-extinguishing cylinder having one end connected to the lead-side contact and a transformer-side arc-extinguishing cylinder having one end connected to the transformer-side contact. Bushing for transformer with cut-out function described in 1. A cannula having a rear end attached to the transformer tank with the front end directed obliquely downward, a lead-side contact accommodated inside the front end of the cannula, and an inner side of the rear end of the cannula The accommodated transformer side contact, the cylindrical fuse container containing the fusible body, and the lead side attached to the one end and the other end of the fusible body respectively attached to the front end and the rear end of the fuse container An electrode and a transformer side electrode, and inserted into the cannula from the tip of the cannula so that the lead side electrode and the transformer side electrode are in contact with the lead side contact and the transformer side contact, respectively. The cutout fuse is disposed in a space between the lead-side contact and the transformer-side contact in the sleeve, and the cutout fuse is pulled out from the sleeve A lead wire drawn from the outside is connected to the lead side contact, and a primary side of the transformer is connected to the transformer side contact. In transformer bushings with cutout function to be connected,
  An end cap having an end plate and a fuse insertion port is attached so as to close the rear end portion and the front end portion of the cannula, respectively, and the contact is disposed concentrically with the cannula inside the front end portion of the cannula. One end of the support cylinder is connected to the end cap,
  The lead side contact is inserted inside the contact support cylinder and is supported on the tubular lead side shield conductor, and the lead side contact is arranged inside the lead side shield conductor to contact the lead side electrode. A contact member,
  The transformer side contact is formed in a cylindrical shape so as to receive a rear end portion of the cutout fuse, one end is supported by the end plate, and the other end is opened to the lead side contact side. And a contact member disposed inside the other end of the transformer-side shield conductor and in contact with the transformer-side electrode,
  The arc-extinguishing cylinder is supported by being inserted inside the lead-side shield conductor at one end side, and a lead-side extinguishing cylinder with the other end opened to the transformer-side contact side, and one end being the transformer-side shield conductor The other end of the transformer is connected via a connecting member and the other end is opened from the transformer side extinguishing cylinder opened to the lead side contact side,
  The connecting member includes a ring-shaped member that surrounds and engages the other end of the transformer-side shield conductor and one end of the transformer-side extinguishing cylinder, and the ring-shaped member is the sleeve. A contact portion between the conductive member and the transformer-side extinguishing cylinder is supported with respect to the sleeve by being brought into contact with the inner peripheral surface of the pipe,
  A ring-shaped support member that surrounds a portion near the other end of the transformer-side arcuate cylinder is provided, and the support member is brought into contact with the inner peripheral surface of the sleeve so that the transformer-side arcuate cylinder is A portion near the other end is supported by the sleeve,
  Between the cannula and the contact support cylinder, between the cannula and the lead-side extinguishing cylinder, between the cannula and the transformer-side extinguishing cylinder, and between the cannula and the transformer-side shield conductor A gap is formed between each of the gaps, and the gap extends through the entire length of the cannula in the axial direction. When the rear end of the cannula is attached to the transformer tank, the cannula is formed. A drainage passage is formed for allowing water present in the pipe to flow down along the inner peripheral surface of the cannula,
  A drainage port having one end communicating with the drainage passage and the other end opening to the outside is provided at the tip of the cannula,
  The connecting member and the supporting member have a gap for allowing water flowing through the drainage passage to pass;
  Bushing for transformer with cut-out function. The bushing for a transformer with a cutout function according to claim 1, 2 or 3, wherein the inner peripheral surface of the sleeve is coated with a resin having water repellency. A transformer tank, a transformer main body accommodated in the transformer tank, a sleeve having a rear end attached to the transformer tank in a state where the tip is directed obliquely downward, and a tip of the sleeve A lead-side contact housed inside, a transformer-side contact housed inside the rear end of the sleeve and connected to the primary side of the transformer body, and a cylindrical fuse containing a fusible body A lead-side electrode and a transformer-side electrode attached to one end and the other end of the fusible body, respectively, attached to the front end portion and the rear end portion of the fuse vessel and the fuse vessel, respectively, from the front end of the sleeve A cutout fuse that is removably inserted into the sleeve so that the lead-side electrode and the transformer-side electrode are brought into contact with the lead-side contact and the transformer-side contact, respectively, and the lead-side contact in the sleeve And an extinguishing cylinder that forms a slit between the cut-out fuse when the cut-out fuse is pulled out of the sleeve, and is arranged in a space between the transformer-side contact and externally. In the transformer with a built-in cutout fuse in which the lead wire to be drawn is connected to the lead side contact,
  Between the cannula and the lead side contact, between the cannula and the extinguishing cylinder and between the cannula and the transformer side contact, a gap is formed to communicate with each other. A drainage passage is formed over the entire length in the axial direction of the cannula to allow water present in the cannula to flow down to the tip side of the cannula along the inner peripheral surface of the cannula,
  A drainage port having one end communicating with the lowermost end of the drainage passage and the other end opening downward;
  A built-in transformer with cutout fuse. 6. The arc-extinguishing cylinder is divided into two parts: a lead-side arc-extinguishing cylinder whose one end is connected to the lead-side contact; and a transformer-side arc-extinguishing cylinder whose one end is connected to the transformer-side contact. A transformer with a built-in cutout fuse described in 1. A transformer tank, a transformer main body accommodated in the transformer tank, a sleeve having a rear end attached to the transformer tank in a state where the tip is directed obliquely downward, and a tip of the sleeve A lead-side contact housed inside, a transformer-side contact housed inside the rear end of the sleeve and connected to the primary side of the transformer body, and a cylindrical fuse containing a fusible body A lead-side electrode and a transformer-side electrode attached to one end and the other end of the fusible body, respectively, attached to the front end portion and the rear end portion of the fuse vessel and the fuse vessel, respectively, from the front end of the sleeve A cutout fuse that is removably inserted into the sleeve so that the lead-side electrode and the transformer-side electrode are brought into contact with the lead-side contact and the transformer-side contact, respectively, and the lead-side contact in the sleeve And an extinguishing cylinder that forms a slit between the cut-out fuse when the cut-out fuse is pulled out of the sleeve, and is arranged in a space between the transformer-side contact and externally. In the transformer with a built-in cutout fuse in which the lead wire to be drawn is connected to the lead side contact,
  An end cap having an end plate and a fuse insertion port is attached so as to close the rear end portion and the front end portion of the cannula, respectively, and the contact is disposed concentrically with the cannula inside the front end portion of the cannula. One end of the support cylinder is connected to the end cap,
  The lead-side contact is inserted into the contact support cylinder and supported by the tubular lead-side shield conductor, and the contact disposed on the lead-side shield conductor and in contact with the lead-side electrode With members,
  The transformer side contact is formed in a cylindrical shape so as to receive a rear end portion of the cutout fuse, one end is supported by the end plate, and the other end is opened to the lead side contact side. And a contact member disposed inside the other end of the transformer-side shield conductor and in contact with the transformer-side electrode,
  A rod-shaped terminal conductor connected to the lead wire drawn from the primary side of the transformer is connected to the transformer-side shield conductor, the terminal conductor is led out to the outside through the end plate,
  A terminal rod having a lead wire connecting portion for connecting the lead wire at one end passes through the side wall near the tip of the cannula and is introduced into the cannula, and the other end of the terminal rod is connected to the lead-side shield conductor. Connected,
  The arc-extinguishing cylinder is inserted and supported at one end inside the lead-side shield conductor and the other end is opened to the transformer-side contact side, and one end of the transformer-side shielding member It is connected to the other end via a connecting member, and the other end is taken from the transformer side extinguishing cylinder opened to the lead side contact side,
  The connecting member includes a ring-shaped member that surrounds and engages the other end of the transformer-side shield conductor and one end of the transformer-side extinguishing cylinder, and the ring-shaped member is the sleeve. A contact portion between the transformer-side shield conductor and the transformer-side extinguishing cylinder is supported with respect to the sleeve by contacting the inner peripheral surface of the tube,
  A ring-shaped support member that surrounds a portion near the other end of the transformer-side arcuate cylinder is provided, and the support member is brought into contact with the inner peripheral surface of the sleeve so that the transformer-side arcuate cylinder A portion near the other end is supported by the sleeve,
  Between the cannula and the contact support cylinder, between the cannula and the lead-side extinguishing cylinder, between the cannula and the transformer-side extinguishing cylinder, and between the cannula and the transformer-side shield conductor Clearances are respectively formed between them, and when the rear end portion of the cannula is attached to the transformer tank, the water existing in the cannula is allowed to pass through the inner peripheral surface of the cannula. A drainage passage is formed over the entire length in the axial direction of the cannula, and flows down to the distal end side of the cannula.
  One end communicates with the lowermost end of the drainage passage, and the drainage port with the other end opened to the outside is provided at the distal end of the sleeve.
  The connecting member and the support member are provided so as to form a gap for allowing the water flowing through the drainage passage to pass through;
  A built-in transformer with cutout fuse. The transformer with a built-in cutout fuse according to claim 5, 6 or 7, wherein an inner peripheral surface of the sleeve is coated with a resin having water repellency.

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