JPS5831295Y2 - Submersible fuse device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a display device for a submersible fuse device, particularly a capacitively coupled fuse device immersed in a liquid, such as water.

Fuse display devices are well known in the art.

A direct-coupled display device is described in US Pat. No. 2,735,088.

In addition, the capacitively coupled display device for external circuit lines is patented in US Patent No. 2.
It is published in No. 036223.

It is also well known to use neon lamps and capacitors for certain purposes with fuses and fuse holders.

Such applications are described in U.S. Pat. Nos. 3,229,065 and 25
No. 45760.

Transparent fuse tubes are also known which exhibit an electroluminescent effect that occurs under certain electrical conditions.

Such usage is described in US Pat. No. 3,513,427.

It would be advantageous if submerged fuses of the type found in underground power lines, whether venting or conducting, were provided with an indicator to indicate the status of the fuse.

It is also advantageous if the electrical coupling of the display device to the fuse is indirect (ie, capacitive) so that the inherent capacitive effect of the main body of the insulating jacket can be utilized.

According to this invention, a submersible fuse device includes a fuse enclosed within a water-resistant immersion jacket.

Almost all of the exterior surfaces of this envelope are coated with conductive paint for safety (i.e., grounding) purposes.

The inner surface of the jacket is coated with conductive paint except in one place between the fuse terminals where semiconductive paint is used.

This conductive paint reduces corona.

This paint serves many functions, one of which is to electrically insulate the separate main terminals of the fuse so that the fuse cannot be shorted through the conductive paint.

Another purpose of the conductive paint is to create a resistance change between the surfaces of the conductive paint inside the envelope to help reduce corona.

According to this invention, conductive parts electrically insulated from each other on the inner surface of the insulator (sheath) are connected to a capacitor on the outer surface of the sheath using suitable insulation technology in order to electrically operate the neon lamp display device in a predetermined condition. are combined.

This coupling is capacitive, so that there is no need to provide holes for electrical conductors for the display.

It does not matter which fuse terminal the fuse load is connected to or which fuse terminal the power supply is connected to.

It is also generally known to use conductive paint as a corona barrier inside the envelope.

It is also known to use gasket materials to seal the finished portions of the jacket.

It would be advantageous if there was a device that could use the gasket area as a corona barrier, and it would also be advantageous if it could somehow be used as a semiconducting paint barrier.

This semiconductive paint serves a dual purpose: to smooth out sharp corners between conductive surfaces and to electrically insulate them.

According to this invention, a gasket is used to seal the seam between two separate parts of the jacket during assembly.

The gasket has an inner section with a bead that covers the corner of the two sections at the seam during assembly.

This corner covering reduces strong field effects at sharp corners.

Also, in immersion type fuses, the inner portion of the envelope is coated with conductive paint except for one central portion which is provided with a band of semiconductive paint.

This semi-conductive paint is applied directly to the inner walls of the envelope, slightly overlapping the edges of the conductive paint.

Additionally, a bead is created in the semi-conductive paint where it overlaps the conductive paint and is fairly arcuate to avoid a sharp interface between the conductive paint and the insulating material interface of the envelope. It is the face of

Therefore, the electric field strength in the portion is reduced.

Referring to the drawings, and in particular to FIG. 1, there is shown a fuse device SFA of the type immersed in a liquid, such as water.

The fuse assembly SFA has a jacket assembled by connecting the bottom portion 62 of the fuse housing to a top lid 64 and sealing the joint surfaces with a suitable gasket 73.

This assembled fuse device SFA is installed in the mounting device 80.

Two terminals 76 and 78 are shown connected in series to a schematically illustrated alternating current source S and to a load LD.

It is shown that a display device 84 is installed in a portion of the lid 64, on which a printed circuit card 85 is placed.
Its use will be described later.

The fuse device SFA is 84C and 84 in Fig. 7, which will be described later.
Conductive layer 8 of paint except for two small parts denoted by d
2 so that the entire external surface of this fuse device SFA is at ground potential for safety purposes, to minimize undesirable corona effects.

Referring now to FIG. 2, the bottom portion 62 of the fuse arrangement SFA
It is shown.

This bottom portion 62 is located offshore from Hughes FC.

This fuse FC includes two ferrules 56 and 58.

The inner surface of the bottom portion 62 has conductive surfaces 86 and 88 coated with a thin layer of conductive paint.

The main body of the bottom portion 62 is made of electrically insulating material.

These conductive surfaces 86 and 88 are on the interior surface of this body of insulating material.

There is a thin annular layer 90 of semi-conductive paint on the inner surface between conductive surfaces 86 and 88, which in small peripheral areas 90a and 90b, described below with respect to the other figures, conductive surface 86.
It overlaps with 88.

This annular layer 90 of semiconductive paint effectively electrically insulates conductive surface 86 from conductive surface 88.

Ferrule 56 is generally proximate conductive surface 86 and electrically connected thereto at location 56a, and ferrule 58 is proximate conductive surface 88 and electrically connected thereto at location 58a. You'll understand.

A flat connecting surface 70 is shown with an open lower part 4a protruding for fastening bolts or the like.

The conductive paint is also present in this open lower part 4a.

Next, regarding FIG. 3, the fuse device SF shown in FIG.
A lid 64 is shown.

It will be seen that the lid 64 includes two electrically conductive ferrule conductors 66 and 68 which will be electrically connected to the ferrules 56 and 58 when the fuse device SFA is assembled.

Ferrule conductors 66 and 68 are electrically connected to terminals 76 and 78, respectively.

On the inside of the lid 64 is a semi-conductive paint 90 that overlaps around the periphery.
There is a thin layer of conductive paint on conductive surfaces 86 and 88 separated by.

This corresponds to the portion with the same name in FIG.

Thus, when the lid 64 is assembled with the bottom portion 62 to form the finished product shown in FIG. , both of which are separated by a continuous annular layer 90.

During assembly, the flat tethering surface 72 of FIG. 3 is positioned to completely overlap the tethering surface 70 shown in FIG.

In the embodiment described herein, a gasket 73 (particularly shown in FIG. 10) is provided between these two surfaces, and a suitable latch device on the other side of hole 74a shown in FIG. is compressed between the two surfaces by turning the fastener 74.

The inner periphery of the connecting surface 70 in FIG. 2 and the inner periphery of the connecting surface 72 in FIG. Corona will occur in the portion, causing insulation deterioration in the lid 64, the bottom portion 62, or both.

A suitable shielding device is shown in FIG.

Next, referring to FIGS. 4 to 8, the bottom portion 62 and the lid 64 are
A plan view and an elevation view of the display device 84 are shown along with a broken section of the capacitively coupled portion of the display device 84.

Looking specifically at FIGS. 4-6, bottom portion 62 and lid 64
An insulating material 87 is shown.

Therefore, either the bottom portion 62 or the lid 64, or both, are two separated conductive plates separated by a portion of insulating material.The insulating material is clearly 87; The conductive plate, in one example, includes an inner conductive surface 86 and an outer conductive layer 82.
(FIG. 7), and in other examples, an inner conductive surface 88 and another portion of the outer conductive layer 82.

For clarity, the actual capacitor plates combined with the external conductive layer 82 of many capacitor devices are the small conductive portions 82 e and 82 described below with respect to FIGS. 7 and 8.
You will find that f.

With particular reference to FIGS. 7 and 8, the display device 84 of FIG.
includes a raised portion 84a that circumferentially surrounds two separate conductive portions 82e and 82f.

This raised portion 84a has two breasts 84b and 84C.
, into which a transparent conductive surface 86 and a printed circuit board 85 are respectively inserted and installed.

A number of electrical components of this printed circuit board 85 are connected to conductive portions 82e and 8 by conductors 84g and 84h, respectively.
2 f is connected in series.

The display device includes a raised portion 84d, the top of which is at the same height as the aforementioned breast 84C.

As a result, conductive portions 82e and 82f are well isolated from each other by the vertical walls of central rib portion 84d.

The display device 84 includes an annular layer 90 shown in FIGS. 4 and 6.
It will be seen that all but 84 C and 84 d are coated with conductive paint, which is covered with a semi-conductive pane I, similar to .

Additionally, conductive portions 82e and 82f are conductive.

In conclusion, it will be appreciated that the conductive surface 86 may consist of substantially transparent plastic glass or other electrically insulating material.

In the embodiment shown, the neon light is connected to the printed circuit board 8.
5 and below the conductive surface 86.

This is to prevent the operator from touching conductive portions 82e and 82f, or any of them.

As will be discussed below, the voltages applied to various portions of conductive surface 86 and the surface of display 84 are not significantly greater than the voltages within conductive surface 86.

Nevertheless, worker protection is still provided.

6 and 7, conductive portion 82e overlaps at least a portion of conductive surface 86 inside the box.

Similarly, conductive portion 82f is connected to conductive surface 88 inside lid 64.
are on the same line.

As a result, capacitive coupling is provided in one example between the conductive portion 82e and the conductive surface 86 and in another example between the conductive portion 82f and the conductive surface 88 by the body 87 of insulating material.

The other parts of the viewing device 84 are conductors 84g and 84h.
is connected in series between the two capacitor sections.

Next, referring to FIG. 9, the annular layer 9 of the semiconducting pane)
The fractured surface of the outer jacket is shown at 0.

This cross section is shown in exaggerated form.

Conductive layer 82 is shown with two spaced apart layers, conductive surfaces 86 and 88.

The main insulating material 87 of the envelope is a conductive layer 82 and a conductive surface 86 .
88 and external terminals 76 and 78.

It will be appreciated that the fairly sharp corners 88a and 88b of conductive surfaces 86 and 88 are areas of high field strength potential where corona discharge occurs.

However, these corners are made of semiconducting material 90a and 90b
It is held in place by a bead.

An annular layer 90 is aligned with conductive surfaces 86 and 88.

In the example shown here, the semiconductive paint is about 2 inches (
51 mm) and completely encloses the inside of the fully assembled jacket.

A device configured in this manner can withstand fuse abnormalities in the event of a failure.

The total line voltage from terminal 76 or 78 due to fuse rupture is reduced to ground potential by this two inch thickness.

The ultimate purpose of combining the conductive surfaces 86 and 88 used for the overlapping and chevron-shaped annular layers 90 is primarily to reduce corona discharge within the envelope.

The use of capacitance between the inner conductive surfaces 86 and 88 and the outer conductive layer assists in performing the display function.

Next, regarding FIG. 10, the lid 64 of the gasket 73 portion
A cross-section of the rupture between the bottom portion 62 and the bottom portion 62 is shown.

A conductive layer 82 and a conductive surface 88 (in this case) are shown on either side of the insulating material 87 of the main body of the envelope (fuse device 5FA).

The capacitive characteristics of an arrangement thus assembled can be easily visualized in this drawing.

fairly sharp corners 62 of the bottom portion 62 and lid 64 interlocking;
a and 643 are areas with high electric field strength where corona is likely to occur.

A gasket 73 is installed inside the outer cover forming the bead 73a.
It is better to secure these corners with arcuate surfaces, such as those created by the extended parts of the

This bead 73a therefore reduces the strong electric field effects at corners 64a and 64a.

This reduces the possibility of corona forming inside the envelope.

In this case, since there is a gasket 73, the lid 64 and the bottom part 6
Air between the edges of the conductive or semiconductive paint at the joint of the two is also expelled.

In this state, the edges 62a and 64 of the assembled envelope are
This acts as a deterrent to reduce the corona surrounding 2.

Positioning the gasket as shown can be achieved either by expelling excess gasket material to the inside when the lid is screwed onto the bottom part, or by first creating a beaded gasket.

The material of this gasket is applied as a flowable liquid so that after attaching the lid to the bottom part, the assembly is oriented so that a bead 73a is created.

Therefore, the connection between the lid and the bottom part is completely closed.

Turning now to FIG. 11, a liquid immersion type fuse with an indicator is shown.

Gasket 1-73 is shown with lid 64 removed from bottom portion 62.

The fuse FC is located in the center of the jacket.

The fuse ferrules are shown at 56 and 58 in the figure.

The spring-loaded connectors are designated 66 and 68, and the external terminals are designated 76 and 78.

Although not shown in other embodiments, conductors 66a and 66
b are attached to ferrules 56 and 58 to connect the ferrules to the inner wall of fuse assembly SFA.

One capacitor plate of ferrule 56 is indicated at 86 and one capacitor plate of ferrule 58 is indicated at 88.

Separating capacitor plates 82e and 82f in conjunction with these capacitor plates 86,88 are shown outside the insulating material 87 to form two capacitors C1 and 02.

A bridge circuit consisting of diodes D1 to D4 includes a capacitor C3 and a lump.

Capacitor plate 82 connects the parallel combination of LAI and resistive element R1 in series to capacitors C1 and C2.
e and 82 f.

Under normal operating conditions, when the lower fuse C is not blown, the currents flowing through the capacitors C1 and C2 are equal, so the voltage between the input terminals of the bridge circuit is zero, and the lamp LAI
is not lit.

In fact, if the capacitor or other physical quantities of this device change even slightly, the voltage will become slightly larger than zero, but
If lamp LAI is at the minimum voltage value and is lit at that voltage value, and the currents in capacitors C1 and C2 are approximately equal and opposite in magnitude, then capacitor C3
This value is not easily reached by chance because it is not easily charged to a voltage large enough to turn on the AI.

In this case, resistive element R1 acts as a leakage resistor to shunt current away from capacitor C3 so that this capacitor is not significantly charged.

However, if the fuse FC were to blow, one of the terminals 76 and 78 would have a significantly higher potential than the other.

This is because one of terminals 76 and 78 is connected to a high voltage source (not shown) and the other to a load (not shown).

Which terminals 76 and 78 are connected to the load and which way is connected to the power source is not important, nor does it need to be known when installing the fuse.

The diode circuits D1 through D4 are such that the display operates regardless of which side of the fuse is connected to the load and which side is connected to the power supply.

It will be appreciated that although two ground points G1 and 62 are shown, this is not the only option.

These provide a device in which the outer conductive layer 82 is grounded and at ground potential.

The annular layer 90 lies between the outer jacket capacitor plates 86 and 88, whereas the radial portion 84d lies between the outer jacket capacitor plates 82e and 82f.

For purposes of illustration, when fuse FC blows, assuming that terminal 76 is connected to a power source and terminal 78 is connected to a load, capacitor plate 86 is at a significantly higher potential than capacitor plate 88.

The annular layer 90 serves to grade the voltage between capacitor plates 86 and 88 to prevent floodover between them.

The annular layer 90 allows the ferrule 5 to be removed without creating high field voltage discontinuities that can cause floodover.
It has the property of being able to withstand voltage abnormalities of the fuse between 6 and 58.

In this case, the capacitor C1 is connected to the ground point and the ferrule 56.
It will receive most of the voltage between the

In some embodiments of the invention, the maximum voltage used between the ferrule and ground is between 15 kilovolts and 60 kilovolts.

In this case, only 150 to 200 volts is the voltage drop across capacitor C1.

The other voltage drop occurs in the parallel combination of capacitor C3, lamp LAI and resistive element R1.

Another capacitor C2 returns the current of the series connected display device 84 to ground by leakage into the conductive layer 82 or through the load connected to the terminal 78.

If the potential difference between the input terminals of the bridge circuit is large enough, capacitor C3 is quickly charged to a voltage sufficient to cause dielectric breakdown of a lamp LAI, such as a neon lamp.

Therefore, the neon lamp acts to create a discharge path for the charge stored in the capacitor C3.

This discharge is quite rapid and of course occurs intermittently.

This fairly rapid discharge and the strength of the discharge pulse are the characteristics of lamp L.
Generates a fairly strong pulse for lighting the AI.

If the lamp were to conduct electricity continuously rather than intermittently, the average value of the current passing through it would be such that even if the lamp was lit for a long time, the brightness of the lighting would not be small.

As a result, when the fuse FC blows, the capacitor C
The lamp LAI, which was working together with C3, shines strongly and intermittently at a frequency that is satisfied by the capacitance value of <C3.

In this case, diodes D4 and Dl act to conduct current, and diodes D1 and D3 conduct little current.

It will be appreciated that in connection with the above embodiments of the invention, not all of the ideas of the invention presented herein need be used simultaneously.

It will also be appreciated that the diagram of FIG. 11 is not limiting.

It merely represents the interrelationship of important elements of the invention.

The conductive surfaces 86 and 88 of capacitors C1 and C2 occupy a significant portion of the interior of the envelope shown in FIG.

The positioning of the display device 84 as shown in FIG. It will also be understood that it may be used as a display device.

Moreover, this device covered by the jacket is not limited to a fuse, but may in some cases be any type of circuit breaker.

Additionally, FIGS. 9 and 10 are generally shown with exaggerated dimensions for ease of explanation.

The device of this invention as described above has a number of advantages.

One advantage is that the conductive surfaces of the inner and outer parts of the envelope that are immersed in liquid create a capacitive coupling between the high voltage device located within the envelope and the status indicator located outside the envelope. It means that it is used for.

Capacitive coupling eliminates the need for holes or openings in the envelope that could allow water or other objects to seep in and damage the elements that are to be protected by the envelope.

Another advantage is that a fuse device can be used without the need for directing the power supply or load by means of a bridge circuit.

This bridge circuit allows the indicator lamp to work on both the left and right sides.

Another advantage is that a flood lamp provides a more easily visible indicator of the status of the elements within the envelope than a permanently lit lamp.

A further advantage is that the energy providing the display is obtained from the fuse-protected power supply by capacitive coupling.

Another advantage is that by using a capacitive element that stores charge, you can not only obtain the flushing effect mentioned above, but also
It is said that a strong lighting pulse for the lamp LAI can be obtained quickly and with a considerably large amount of current through the AI, and that this lamp can be seen from a long distance from the street surface through the mouth of a manhole. .

In addition, one advantage is that the semiconductor material used to create an abnormality in the fuse element is a considerable part of the semiconductive paint, and also has the function of suppressing angles, so that when the area with high electric field strength is suppressed, V It is! In addition, the gasket material used in the first section was removed and other methods were used to form a bead of the material against the edge of the vertical part and reduce the electric field strength at the edge. , physsioniva, □corona, or other undesirable effects.

In addition, the advantage of □si (as shown in Fig. 19 □, the □ raised portions 90 a and 90 b provide light to the □ conductive surface 86) is that the □ distance 'C□ is Ning? It is called heather because it produces distance.

Accordingly, this reduces the tendency for flutter over to occur along the outer surface of the annular layer 90 made of semiconductive paint.

[Brief explanation of the drawing]

Figure 1 is a perspective view of the underwater fuse jacket of the underwater fuse device of this invention, and Figure 2 shows the bottom part of the jacket in Figures 1 and 1.
Perspective view, 3rd A is the 3rd, (perspective view of the outside of the instep, the top of the cover, Fig. 4 1≠Fig. The figures are side views of the outer sheathing shown in Figures 4 and 4. Figure 6 is a plan view of the top of the outer sheathing shown in Figure 1. Figure 7 is a top view of the outer sheathing shown in Figure 0!' Fig. 8 is a side view of the lid part shown in Fig. 6, Fig. 7, and Fig. 9 (Fig. The part of the outer cover shown in Figure 1 was broken, cut, and
．． 0. llK was shown in Figure 1. Cross-sectional view of the part connected to the top p7 bottom part, Figure 1 (
FIG.
, 1. Note that in these drawings, the FIT symbols are considerably different from each other. On the drawing! 2. Outer covering: , , , , 62, 61
! . 7. i′ combined,, display Rinhiro:・-,
=-841, hiss. Two... □・F'co',,,1. ,,・.

Claims (2)

[Scope of utility model registration request] (1) a jacket having first and second spaced apart terminal devices extending from an inner portion of the jacket to an outer portion; the first portion forming the conductive surface of the inner portion is electrically isolated from the second portion forming the conductive surface of the inner portion; The inner portion and the outer portion each have a first portion and a second portion such that the first portion forming the conductive surface of the outer portion is electrically isolated from the second portion forming the conductive surface of the outer portion. a first portion of the inner portion and a first portion of the outer portion are capacitively coupled via the insulating material;
A second portion of the inner portion and a second portion of the outer portion are capacitively coupled via the insulating material, and a protective fuse device is provided within the jacket, the fuse device being spaced apart. 1st. a second electrically conductive ferrule device;
The first ferrule device is connected to the inner first portion of the first terminal device, and the second ferrule device is connected to the inner second portion of the second terminal device, and the second ferrule device is connected to the inner second portion of the second terminal device. An electrical indicating device is provided on the outside of the envelope to indicate when the device has fused, the electrical indicating device being connected in series between a first part of the outer part and a second part of the outer part. and therefore, the electrical indicating device applies at least one of the ferrule devices so as to apply a voltage generated between the one ferrule device and the electrical measurement reference point between the first and second portions when the fuse blows. a submersible type fuse device, the electrical indicating device being capacitively connected in series with one another and acting to indicate that the fuse is blown by the voltage; (2) The fuse of the fuse device has a pair of terminals each having a phenol device.Claim (1)
Submersible fuse device as described.