JPH0115033B2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field This invention is designed to quickly detect fault points such as ground faults and short circuits in power distribution lines by directly suspending them from electric wires so that overcurrent caused by accidents can pass through the power lines. This invention relates to an overcurrent passage display device that displays when an overcurrent has passed.

Prior Art This applicant has already stored a colored fluid 71 having viscosity such as oil in a display cylinder 70 as an overcurrent passage display device as shown in FIGS. A display valve 72 is proposed. Further, this indicator valve 72 had a pair of butterfly-shaped valves 74 mounted on both sides of a valve mounting piece 73 so as to be rotatable downward by a hinge 75. The display valve 72 is normally operated by the display cylinder 7.
The display valve 72 is brought into contact with the display window 76 provided at the bottom of the display window 76 so that it can be clearly seen. The colored fluid 71 is made visible to indicate the passage of an overcurrent,
Thereafter, it was lowered with a delay due to its own weight while resisting the resistance of the fluid 71 and returned to its original position. However, as mentioned above, the display valve 72 has a valve mounting piece 73, a butterfly valve 74,
Since the hinge 75 is separate, assembly is troublesome and the number of parts increases.

OBJECTS The present invention is to provide an overcurrent passage display device which eliminates the above-mentioned drawbacks, reduces the number of parts of the display valve, and can be easily assembled.

An embodiment embodying the present invention will be described below with reference to FIGS. 1 to 16.

In the drawings, reference numeral 1 denotes a cylindrical main body case made of synthetic resin, which is constructed by screwing a lower case 3 onto the lower outer periphery of an upper case 2. Reference numeral 3a denotes an annular locking projection protruding from the inner periphery of the lower end opening 3b of the lower case 3. Reference numeral 27 denotes a luminous reflective tape affixed to the boundary line between the upper case 1 and the lower case 3 and to the lower outer periphery of the lower case 3.

Reference numeral 4 denotes an annular locking step protruding inward from the inside of the lower part of the upper case 2, and 5 denotes a disc-shaped locking plate attached with screws 4a to the locking step 4. It is formed to be slightly smaller than the inner diameter of the case 2, and has an insertion hole 5a formed in the center thereof. Reference numeral 6 denotes four screw holes recessed at equal distances from each other on the upper surface of the peripheral wall of the upper case 2, and 7 is an annular protrusion similarly provided on the upper surface of the upper case 2.
The case 2 is curved inward at four places to avoid this.

Reference numeral 8 shown in FIG. 2 is a disc-shaped lid made of a weather-resistant insulator such as rubber attached to the upper surface of the upper case 2, and the fitting is narrower than the width of the protrusion 7. Watertightness is ensured by providing a groove 8a on the lower surface and fitting it into the protrusion 7, and tightening bolts 9 screwed into each of the screw holes 6 through the bolt holes 8b. Note that 10 and 11 are flat washers and spring washers interposed between the bolt 9 and the lid 8.

Reference numeral 12 denotes a mounting portion projecting upward from the top surface of the lid body 8, which extends in the diametrical direction and has a hooking recess 12a formed in the center of the top surface with an arcuate cross section. Reference numeral 29 denotes a flexible groove having a mountain-like or concave cross-section formed in the multiple-strip clamping recess 12a along the wire insertion direction. Reference numeral 13 denotes an inverted U-shaped upper core case that is removably attached to the upper surface of the attachment part 12 so as to straddle the clamping recess 12a, and is made of an insulating material such as weather-resistant rubber. There is. 14 is an inverted U-shaped upper core made of a magnetic material that is inserted when the upper core case 13 is molded, and 15 is a U made of a magnetic material that is inserted into the attachment part 12 when the lid body 8 is molded.
It is a letter-shaped lower core, and together with the upper core 14 constitutes a detection cut core 16 which is formed in an annular shape so as to surround the outside of the electric wire 1 in the assembled state. L is a coil wound around the lower core 15, and together with the detection cut core 16 constitutes a detection current transformer 17.

A tapered recess 13a is formed on both lower end surfaces of the upper core case 13 along the outer edge of the cut surface 14a of the upper core 14 and becomes wider toward the bottom.
Tapered protrusions 12b are formed on the upper surface of the mounting portion 12 and are tightly fitted into the recesses 13a, thereby preventing rainwater from entering through the wedge effect.

Reference numeral 18 denotes a presser plate whose central portion is integrally molded within the upper part of the upper core case 13, and each end thereof projects from both sides of the upper core case 13 in the longitudinal direction. Reference numeral 18a denotes an insertion hole formed through one end of the presser plate 18, and reference numeral 18b denotes a locking recess formed by a cutout from one side of the other end of the presser plate 18.

Reference numeral 19 denotes a fastening member implanted in the lower part of the mounting portion 12 of the lid body 8, and as shown in FIG. They are welded together and threaded portions 19c provided at the tips protrude from the upper surface of each side of the mounting portion 12 in the longitudinal direction. Then, by inserting each screw portion 19c into the insertion hole 18a and the locking recess 18b of the holding plate 18, and screwing the wing nut 20 from the upper surface of the holding plate 18, the upper core case 13 is attached to the mounting portion 12. The upper core 14 and the lower core 15 of the detection cut core 16 are fastened and fixed to each other so that the cut surfaces 14a and 15a of the detection cut core 16 are pressed into close contact with each other.

Note that 19d is a through hole extending in the longitudinal direction of the substrate 19a of the clamping member 19, through which a lead wire (not shown) led out from the coil L can be inserted. Reference numeral 21 denotes a spring washer interposed between each end of the holding plate 18 and each wing nut 20. 22 is a locking recess 18b of the presser plate 18
It is a reverse channel-shaped retaining plate interposed between the side end and the spring washer 21, through which the tip of the bolt 19b is inserted, and the hanging parts 22a at both ends are on both sides of the retaining plate 18. When engaged, the bolt 19b is prevented from coming off horizontally from the locking recess 18b during assembly.

23 is the upper core case 13 as shown in FIG.
It is a clamp member made of an elastic material that is removably attached to a mounting recess 24 formed in the center of the lower surface of the mounting recess 24, and the upper end surface is opposite to the locking steps 24a formed on both sides of the lower surface of the mounting recess 24. A locking protrusion 23a protruding from the edge can be locked.
Reference numeral 23b is a clamping recess that is recessed in the lower surface of the clamp member 23 and has an arcuate cross section along the wire insertion direction, and the clamping recess has a plurality of threads in the cross-sectional shape of a mountain or a recess along the wire insertion direction. Flexible groove 28 of shape etc.
is formed. Then, insert the electric wire l between the clamping recess 23b and the clamping recess 12a of the mounting part 12,
A wing nut 20 screwed onto the bolt 19b presses the clamp member 23 downward through the upper core case 13 to clamp it between the two members 12a and 23b. Further, both the clamping recesses 12a, 2
By the flexible grooves 28 and 29 of 3b, when the main body case 1 is tilted obliquely with respect to the electric wire l due to the influence of wind, etc., it is made to return to its original state, that is, hang down, with respect to the electric wire l due to the weight of the device.

Note that the clamping recesses 2 each have a different radius of curvature.
3b may be prepared, and one suitable for the thickness of the electric wire l may be selected and used. Reference numeral 25 denotes a protective cover made of synthetic resin in the shape of a square cylinder with a lid and formed to cover the upper part of the bolt 19b and the entire upper core case 13, and has a locking protrusion 25a protruding inward on the lower edge of the peripheral wall. It can be attached by engaging with a locking groove 26 that is recessed around the entire circumference of the attachment portion 12 .

By the way, the overcurrent passage display device according to the embodiment of the present invention can be roughly divided into a current detection section A that detects an overcurrent, a display drive section B operated by the detection section, and the display drive section as shown in FIG. The display device I is configured by a drive transmission mechanism section H that transmits the driving force of B, and a display device I that is operated for display by the drive transmission mechanism section H.

Therefore, first, the current detection section A will be explained. This detection section consists of the above-mentioned detection current transformer 17.
and a step-up transformer 54 (which may be omitted) connected to the coil L. 55 is a surge absorber connected in parallel to the secondary side of the step-up transformer 54.

The display drive section B includes a full-wave rectifier 56 connected to the transformer 54, a capacitor C connected to the output side of the rectifier, and a bidirectional trigger diode TD and relay X connected in parallel to the capacitor.
, a variable resistor R that is also connected in parallel to the capacitor C for changing the voltage applied to the capacitor C, a contact Xa of the relay X and a rotary solenoid RS that are also connected in parallel with the capacitor C. It consists of a series circuit of

As shown in FIG. 1, the rotary solenoid RS is fixed to a vertical portion 5b projecting upward from one side edge of the locking plate 5, and when it is energized, the output shaft is rotationally driven, and when the energization is released, the rotary solenoid RS is installed inside. The output shaft is configured to be rotated back to its original position by a return spring S serving as a force storage member. When the terminal voltage of the capacitor C reaches a certain value (for example, when an overcurrent flows), the trigger diode TD becomes conductive and the relay X is activated. As a result, the a contact Xa of the relay X is closed and the rotary solenoid RS is rotated by a predetermined angle (45 degrees in this embodiment) in the driving direction.

Next, the drive transmission mechanism section H will be explained.

Reference numeral 50 denotes an L-shaped bearing plate which is attached with screws 50a on the locking plate 5 parallel to and opposite to the vertical portion 5b, and is arranged such that the insertion hole 5a is located between the vertical portion 5b and the vertical portion 5b. I have to. Reference numeral 51 denotes an L-shaped bracket protruding from the upper vertical portion 5b of the coaxial bearing plate 50, the base end of which is attached to the bearing plate 50 with a screw 51a, and the tip thereof parallel to the bearing plate 50.

Note that 52 indicates the upper part of the vertical portion 5b and the bracket 51.
This is a spacing plate with both ends fixed to the upper part.

57 is a drive gear fixed to the output shaft of the rotary solenoid RS; 58 is a rotation shaft whose both ends are rotatably attached between the vertical portion 5b and the bracket 51; A driven gear 60 that meshes with 57 is fixedly attached.

The ratio of the number of teeth between the drive gear 57 and the driven gear 60 is a constant ratio (in this embodiment, it is 4:
1).

Reference numeral 61 denotes a rotating plate having a shaft 61a attached to the vertical portion 5b side of the bearing plate 50 so as to be freely rotatable in both directions, and the center of the shaft 61a coincides with the axis of the rotating shaft 58. The lower center of the circumferential surface corresponds to the insertion hole 5a. 61b is a V-shaped groove recessed in the lower circumferential surface of the rotating plate 61. 62 is the same rotating plate 61
It is a pin protruding from the lower side surface on the side of the vertical portion 5b, and its tip is provided with a guide slope 62a as shown in FIG. 63 is bracket 51
It is a tripping member whose base end is fixed diagonally above the rotating shaft 58 with respect to the rotating plate side surface of the distal end, and the distal end is formed so as to descend diagonally downward and forward. .

Reference numeral 64 denotes an elastic operating lever whose base end is fixed to the rotating shaft 58 so as to be interposed between the rotary plate 61 and the bracket 51, and which projects in the radial direction from the base end, and whose distal end is connected to the puller. It can be engaged with and detached from the lower surface of the detaching member 63 and the pin 62. In addition, in the normal state, the actuating lever 64 is clamped between the lower surface of the proximal end of the tripping member 63 and the surface of the bracket 51, so that the slightly vertical portion 5
It is bent towards the b side.

The driving gear 57, driven gear 60, rotating plate 6
1, the pin 62, the tripping member 63, and the operating lever 64 constitute a drive transmission mechanism H.

Next, the display device I will be explained.

Reference numeral 30 denotes a bottomed cylindrical display tube made of colorless and transparent synthetic resin, which is provided below the drive transmission mechanism H, and a hook portion 32 whose diameter is enlarged at the lower end via a locking step portion 31. The outer periphery of the hook portion 32 is screwed into the opening 3b of the lower case 3 so that the lower portion 32a of the hook portion 32 protrudes from the lower edge of the lower case 3. The locking step portion 31 is an annular groove 33 recessed in the lower surface of the locking protrusion 3a.
Watertightness is ensured by being pressed against the inner O-ring 34.

Further, the outer periphery of the display tube 30 is colored with a light reflecting material 35 having a high light reflectance such as white, silver, yellow, etc. by means of coating or the like. The light reflecting material 35 may be colored on the inner periphery of the display barrel 30 by means of coating or the like, or may be applied on the inner periphery of the lower case 3.

Reference numeral 36 denotes a synthetic resin lid that is watertightly adhered to the upper end opening of the display tube 30, and has an attachment hole 36 in the center corresponding to the insertion hole 5a of the locking plate 5.
A is transparent. As shown in FIG. 5, a mounting cylinder 37 is fitted into the mounting hole 36a, and a tubular magnet 38 having a through hole 38a in the center is fixed inside the mounting cylinder 37. Furthermore, the magnet 38
A magnetic fluid 39 is arranged so as to close the through hole 38a. The magnetic fluid used is, for example, finely powdered iron oxide with a diameter of about 1/100,000 mm mixed with a liquid such as oil. The hole 38a is sealed.

Reference numerals 40 and 41 indicate a colored fluid (in this example, red) with low specific gravity and high viscosity and a transparent fluid (in this example) with high specific gravity and low viscosity, which are stored in the display tube 30 in required amounts in upper and lower layers, respectively. colorless). In addition, the ratio of the specific gravity of both 40 and 41 is
Setting it to 2.0 or more is desirable because the two-layer separation is stable, but even if it is set to 1.5 or more, the longer the standing time is, the better the separation will be, so this setting is also acceptable. Also,
Both fluids 40 and 41 are liquids whose viscosity changes little due to changes in external annular conditions, for example, silicone oil is used as the colored fluid 40, and Fluorinert (Minnesota Mining & MFG) is used as the transparent fluid 41.
Company's proprietary trademark), fluorocarbon oil, and other fluorine-based inert liquids are used to prevent them from mixing with each other.

In the colored fluid 40, there is used a pigment (red in this embodiment) whose specific gravity is equal to or greater than that of the fluid and smaller than the specific gravity of the transparent fluid 41. It is preferable that this pigment is uniformly soluble in the fluid, but even if it is precipitated in a layer below the colored fluid 40 when left still, it will impair the function of the colored fluid 40 in this embodiment. It's not a thing.

Reference numeral 42 denotes a string-like member as an operating member whose upper end is engaged with the circumferential surface of the rotary plate 61 corresponding to the pin 62, and is inserted into the insertion hole 5a of the locking plate 5 and the through-hole 38 of the magnet, Also, the fluids 40, 4 are always
The lower end of the bead 44 is inserted into a through hole 43a at the center of a valve element 43, which serves as an indicator valve located in the display valve 1, and is engaged with a bead 44 that abuts the lower surface of the valve element 43.

This valve body 43 has flexibility and the colored fluid 41
and a disc-shaped synthetic resin whose specific gravity is higher than that of the pigment and lower than that of the transparent fluid 40, and is fitted with a small gap so as to be movable up and down with respect to the inner periphery of the display cylinder. As shown in the figure, a pair of semicircular butterfly valves 46 are integrally formed in a symmetrical manner with a groove 45 recessed in the diametrical direction of the upper surface as a boundary. A pair of regulating plates 47 are respectively protruded from the upper surface of one of the butterfly-shaped valves 46, and the tips of the regulating plates 47 are respectively latched to the upper surface of the other butterfly-shaped valve 46 and rotated through the groove 45. Centered butterfly valve 46
It is impossible to rotate upward, and only downward rotation is possible. Note that the meaning that the butterfly valve 46 cannot be rotated upward does not mean that a slight upward rotation is denied.

Further, the valve body 43 is formed into a conical shape with the center of its lower surface protruding, and the same light reflecting material 35 used for the display tube 30 is applied to the lower surface by means of coating or the like. In a normal state, the valve body 43 floats on the transparent fluid 41 so that its entire lower surface is in contact with the transparent fluid 41, and is positioned with a gap from the bottom 30a of the display cylinder 30 which also serves as a display window.

The valve body 43 is integrally formed with a synthetic resin having a specific gravity smaller than that of the colored fluid 40, and a weight having a specific gravity greater than at least the colored fluid 40 and the pigment is attached to the center of the valve body 43 to form a weight portion. By forming the valve body 43, the specific gravity of the entire valve body 43 can be made smaller than that of the transparent fluid 41 and larger than the specific gravity of the colored fluid 40 and the pigment, so that the lower surface of the valve body 43 is in contact with the transparent fluid 40. good. In this way, the valve body 43 can be stabilized, and by appropriately changing the weight of the attached valve body 43, the time for the valve body 43 to settle in the colored fluid 40 can be adjusted to a desired time. The settings can be made easier. Further, instead of forming the lower surface of the valve body 43 in a conical shape, it may be formed into a V-shaped slope slanting upward from the center of the lower surface.

Note that 65 is a guide portion that guides the string-like member 42 protruding from the lower side surface of the bearing plate 50 so as to be located between the rotary plate 61 and the display device I.

To explain the operation of the overcurrent passage display device configured as above, when a normal load current is flowing through the electric wire I as shown in FIG. The display tube 3 is energized by
The valve body 43 is shown from the bottom 30a of 0.

If an overcurrent flows through the electric wire l due to an accident in this state, a transformed current is generated by the transformer 17 shown in FIG.

When the voltage of the capacitor C reaches a certain value,
Trigger diode TD becomes conductive and relay X
is excited and closes its a contact Xa. As a result, a return spring S equipped with a rotary solenoid RS
When the output shaft is rotated 45 degrees in the driving direction against the elastic force of , the operating lever 64 moves from the position shown by the solid line in FIG. Rotated 180 degrees in the direction of the arrow. At this time, as shown in FIG. 4, the operating lever 64 that has rotated downward comes into contact with the guide slope 62a of the pin 62 of the rotating plate 61 located below the rotating shaft 58, but due to its elasticity, it bends toward the bracket 51. The pin 6 is bent while sliding on the guide slope 62a.
Overcome 2. Note that the operation of the operating lever 64 due to the rotation of the rotary solenoid RS up to this point is instantaneously performed.

Then, the rotary solenoid has finished rotating.
The output shaft of the RS starts to rotate back in the opposite direction, that is, in the counter-driving direction, by the built-in return spring S. As a result, the operating lever 64 is connected to the drive gear 5.
7. When the driven gear 60 and the rotation shaft 58 are rotated from the position shown by the chain line in FIG. The string member 42 is then rotated in the opposite direction to wind up the string member 42. Therefore, the display device I is pulled upward through the string member 42 while resisting the gravity of the valve body 43 and the viscous resistance of the fluids 40 and 41.

At this time, the valve body 43 is connected to the butterfly valve 46 as shown in FIG.
is rotated while being bent downward, and the entire body is moved into the colored fluid 40.

Furthermore, when the actuating lever 64 is rotated in the counter-driving direction, the tip of the actuating lever 64 comes into contact with the tripping member 63, and then slides while being pressed against the tripping member 63, so that its elasticity causes the bracket to close. The tripping member 6 is bent while being bent toward the 51 side.
The return operation is completed at the proximal end of 3. At this time, the valve body 43 of the display device I is positioned above the colored fluid 40 as shown in FIG. 14 to display an overcurrent passage.
The color of the colored fluid 40 can be visually recognized through the bottom 30a of the display tube 30. Note that when viewed from the lower side of the display tube 30, the colored fluid 40 cannot be directly seen because the hook 32 gets in the way.
Since the color of the part 32a is diffusely reflected, it is possible to confirm the overcurrent passing indication by the coloration of the part 32a. Alternatively, when the hook portion 32 is made to have the same diameter as the display cylinder 30, the same effect can be obtained, and the overcurrent passage display can be confirmed.

On the other hand, when the operating lever 64 is bent, the first
As shown in Figure 1, from the operating lever 64 to the rotary plate 61
The pin 62 is removed. Then, as shown in FIG. 15, the valve body 43 of the display device I begins to descend due to its own weight, is delayed by the viscous resistance of the colored fluid 40, and returns to the bottom after a predetermined period of time, resulting in a normal display. During this downward movement, since the lower surface of the valve body 43 is formed into a conical shape, the colored fluid 40 on the lower surface of the valve body 43 flows upward along the oblique lower surface, and the transparent fluid 40
When the colored fluid 40 returns to floating on the upper surface, the colored fluid 40 having a light specific gravity does not remain on the lower surface of the valve body 43.

On the other hand, as shown in FIG. 12, the rotating plate 61 is pulled by the valve body 43 via the string member 42,
is returned below the rotating shaft 58.

In this embodiment, the colored fluid 4
The light transmitted through the colored fluid 40 is reflected by the light reflecting material 35, and when viewed from below the display barrel 30, the color of the colored fluid 40 can be clearly seen.

In addition, since the diameter of the hook portion 32 of the display tube 30 is enlarged via the locking step portion 31, the amount of fluids 40, 41 used can be reduced, while the field of view is widened, so that the display state of the display tube 30 can be adjusted. Can be visually recognized. Furthermore, the hook portion 32 is located at the bottom 30 of the display tube 30.
Since it is located below point a, the bottom part 30a serving as a display window does not come into direct contact with the floor surface when transporting this overcurrent passage display device, thereby preventing the bottom part 30a from being scratched by contact.

Note that this invention is not limited to the above-mentioned embodiments, and may be arbitrarily modified without departing from the spirit of the invention, such as making the shape of the display valve V-shaped in cross section as shown in FIG. 17. It is possible.

Although not directly related to the present invention, as shown in FIG. 18, an inverted L-shaped core case portion 67 is formed protruding from the upper surface of one side of the mounting portion 12 in place of the upper core case 13. It is conceivable that an L-shaped lid core case 68 connecting the protruding end 67a of the portion 67 and the upper surface of the other side of the attachment portion 12 is detachable. In this case, the detection cut core 16
is composed of a first cut core inserted into the mounting portion 12 and the core case portion 67, and a second cut core inserted into the lid core case 68. The other ends of tension springs 69 are attached to both sides of the lid core case 68, and one end of the tension spring 69 is attached to both sides of the core case part 67, respectively. is urged downward by the same tension spring 69 and cannot be removed. Note that a fitting recess 68a is formed at the lower end of the lid core case 68, and a fitting protrusion 66 that fits into the fitting recess 68a is formed on the upper surface of the mounting portion 12 corresponding to the fitting recess 68a. Reference numerals 81 and 82 denote a cut surface of the first cut core exposed in the fitting protrusion 66 and a cut surface of the second cut core exposed in the fitting recess 68a, respectively.

Effects As described in detail above, the present invention stores fluid in an indicator cylinder, arranges an indicator valve connected to an actuating member in the fluid, and activates the indicator valve via the actuating member when an overcurrent occurs. In the overcurrent passage display device, the overcurrent passage is indicated by pulling up the overcurrent passage, and after the overcurrent is resolved, the display valve is delayed and lowered by its own weight to perform the display operation. By integrally forming the pair of butterfly-shaped valves, which can be used in a variety of ways, from a flexible synthetic resin, the number of parts of the display valve can be reduced, assembly can be simplified, and the display and return can be easily performed.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment embodying the present invention, FIG. 2 is an exploded perspective view of the upper part of the overcurrent display device, and FIG. 3 is a current detection section and display drive of the overcurrent display device. Figure 4 is an explanatory diagram showing the pins of the rotary plate of the drive transmission mechanism, Figure 5 is a central sectional view of the lid of the display tube, and Figure 6 is the display valve. 7 is a partially sectional perspective view, FIG. 8 is a perspective view showing the normal state position of the operating lever of the drive transmission mechanism, and FIG. 9 is a 180 degree operation from the state shown in FIG. 8. FIG. 10 is a perspective view of the state in which the rotary plate is driven by the operating lever from the state in FIG. 9, and FIG. 11 is the state in FIG. 10. 12 is a perspective view of the rotating plate in a state where the pin of the rotating plate is detached from the operating lever; FIG. The figure shows the display device when the display valve is in the raised state, Fig. 14 shows the display device in the overcurrent passage display state, and Fig. 15 shows the display device when the display valve is in the raised state.
16 is a perspective view of the clamping member, FIG. 17 is a sectional view showing another embodiment, FIG. 18 is an explanatory diagram not directly related to the present invention, and FIG.
9 and 20 are cross-sectional views showing a conventional indicator valve in a lowered state and a raised state, respectively. Display cylinder...30, fluid...40, 41, string-like member (operating member)...42, valve body (display valve)...43, butterfly valve...46.

Claims (1)

[Scope of Claims] 1. Fluid is stored in an indicator cylinder, and an indicator valve connected to an actuating member is disposed within the fluid, and when an overcurrent occurs, the indicator valve is pulled up via the actuating member to suppress the overcurrent. In an overcurrent passage display device that displays a passage of current and performs an indication operation by delaying the display valve down by its own weight after the overcurrent is resolved, the display valve has a pair of valves that can only be rotated downwardly about a diametrical line. An overcurrent passage display device characterized in that a butterfly-shaped valve is integrally formed from a flexible synthetic resin. 2. The overcurrent passage display device according to claim 1, wherein the indicator valve has a pair of left and right butterfly valves symmetrically divided around a groove recessed in the diametrical direction of the upper surface. 3. The overcurrent passage display device according to claim 1 or 2, wherein the lower surface of the indicator valve is formed in a V-shape or a conical shape with the center protruding downward. 4. The fluid consists of a transparent fluid with a high specific gravity and a colored fluid with a low specific gravity and viscosity, which are separated into upper and lower two layers, and the specific gravity of the indicator valve is smaller than the specific gravity of the transparent fluid and larger than the specific gravity of the colored fluid. An overcurrent passage display device according to any one of claims 1 to 3. 5. A weight part is provided in the center of the display valve, and the butterfly valve is made of synthetic resin having a specific gravity lower than that of the colored fluid.
5. The overcurrent passage display device according to claim 4, wherein the specific gravity of the entire indicating valve is smaller than the specific gravity of the transparent fluid and larger than the specific gravity of the colored fluid.