JPS5841707Y2 - Power fuse blown warning device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power fuse blowout warning device, for example, to a power fuse blowout warning device for a switchgear equipped with a power fuse.

FIGS. 1a to 1c are a front view, a plan view, and a side view, respectively, for explaining the main parts of a power fuse blowout alarm device in a conventional switchgear with a power fuse.

In the figure, a power fuse section for three phases is illustrated, but the contact mechanism section and operation mechanism section of the vacuum electromagnetic contactor attached to the lower part thereof are omitted.

In the figure, 1 is a power fuse, 2 is a fuse tube, 3 is a fuse tube cap, 4 is a fuse holder,
Reference numeral 5 denotes a mounting bracket that is fixedly attached to the fixed electrode side 8 of the vacuum interrupter 1 that penetrates and protrudes from the upper wall 6a of the molded insulating frame 6.
is installed.

7 is a power supply side terminal attached to the fixed electrode side of the vacuum interrupter 1.

Both sides of the molded insulating frame 6 have connecting flanges 6b that protrude horizontally, and these are placed on the upper surfaces of the metal frames 9, which are left and right side plates, and are fixed by tightening bolts.

Reference numeral 10 indicates a blowout indicator rod for the power fuse 1, and numeral 11 indicates an operating lever that is pushed forward by the protrusion of the blower indicator rod 10 when the fuse blows out. When the fuse blows, the operating lever 11 is pushed forward by the blowout indicator rod 10 and rotated, rotating the cam 14 and operating the microswitch 15. It is configured to know when a fuse has blown.

Reference numeral 16 denotes a bearing frame (fusion display mounting base) that supports the shaft 12 for the operating lever 11, and a protective cover (for example, a transparent acrylic cover) 17 is attached to the bearing frame 16.

Reference numeral 18 denotes an insulating barrier that is fitted and fixed in a groove provided in a protrusion 6C provided on the upper wall 6a of the mold insulating frame 6.

In this case, the shaft 12 for the operating lever 11 passes through the insulating barrier 18 and is supported by the bearing frame 16.

With the above configuration, when the fuse wire of the power fuse 1 is blown, the blown indicator bar 10 of the power fuse 1 is pushed out and the operating lever 11 is rotated, so the cam 14 also rotates and the micro Switch 15 operates to issue a fusing alarm.

However, if the conventional configuration as shown in FIG. It had the disadvantage of shortening the distance.

Therefore, in the past, a large interphase insulation distance was required, which hindered miniaturization.

Therefore, the present invention was devised to eliminate such conventional drawbacks. Namely, the power fuse has a built-in spring force that pushes out the blown indicator bar when the fuse is blown. An insulation transmission rod section having a rod pushed out by a blowout indicator rod is attached, a cam section for operating a microswitch is provided at the tip of the insulation transmission rod section, and the camshaft serves as an insulation barrier for insulating each power fuse from others. The lengthwise distance of the insulation transmission rod portion is extended to a position where it does not penetrate through the insulation transmission rod portion, and the insulation transmission rod portion is provided with a microswitch operated by the cam portion, and when the fuse blows, the blowout indicator rod is pushed out by a spring force built into the electric power fuse. , the power fuse blowout alarm device is characterized in that the displacement is transmitted to the cam section via the rod of the insulated transmission rod section, and the microswitch is operated to issue an alarm. This will be explained below using examples.

FIGS. 2a to 2c are a simplified front view, a plan view, and a side view of essential parts of the present invention, respectively, showing an embodiment of a molded switchgear with a power fuse to which the present invention is applied.

In FIG. 2, power fuses 23 are installed for each phase on the upper wall 22a of a box-shaped fully molded insulating frame 22 that houses the contact mechanism and operation mechanism (only a portion is shown) of the vacuum interrupter 21. The power fuses 23 of each phase are connected between the upper wall 22a of the entire molded insulating frame 22, the protrusion 22a provided in the groove 24b
An insulating barrier 25 is fitted and fixed to.

The all-molded insulating frame 22 has a box-shaped structure with only the front side open and the other five sides closed, and the front side houses the contact mechanism section, operation mechanism section, etc. of the vacuum interrupter 21, and then a transparent protection plate 26 is installed. is installed.

In FIG. 2, only a part of the operating mechanism of the vacuum interrupter 21 is not shown, and the rest are omitted.

This all-molded insulating frame 22 includes a top wall 22a, left and right side walls 22C, a back wall 22d, and a bottom wall (not shown), and metal legs are attached below the bottom wall.

In the entire molded insulating frame 22, there is a top wall 2 in the upper part where the contact mechanism including the vacuum interrupter 21 is disposed.
Two vertical interphase barriers 22e connecting the rear wall 22a and the rear wall 22d are formed to a sufficiently lower position, and protrude horizontally from the inner surface of the rear wall 22d and continue to the rear wall 22f.

The fixed electrode side of the vacuum interrupter 21 is coupled to a main circuit upper terminal (power supply side terminal) 27 placed on the upper wall 22a.

Reference numeral 28 denotes an operating shaft rotatably fitted on bearing blocks 29 attached to the left and right side walls 22C, and the operating shaft 28 is connected to an operating electromagnet by a tightening bolt 37.
A movable iron core 30 (not shown) is attached, and an operating lever 31 is attached to the operating shaft 28 with a tightening bolt 36.

The operation shaft 28 is rotated by the attraction of the operation electromagnet, and the operation lever 31 pushes up the movable part of the vacuum interrupter 21 via the pressure spring 32, thereby closing the electrode.

In addition, in the open state, the operating lever 31 is activated by the force of a cutoff spring (not shown) of the operating electromagnet to close the vacuum interrupter 21.
The movable part of the vacuum interrupter 21 is pushed down to maintain a shutoff distance against the self-closing force of the vacuum interrupter 21.

Note that 33 is an insulating rod, 34 is a connecting portion, and 35 is a lead rod.

Next, the configuration of the power fuse side on the upper wall 22a of the all-molded insulating frame 22 will be described.

In the power fuse 23, 23a is a fuse tube;
b is a fuse cap, and 23C is a terminal board.

Reference numeral 41 denotes a mounting bracket attached to the power supply side terminal 27, and the terminal plate 23C is attached to this mounting bracket 41 with bolts 42.

An insulated transmission rod portion 43 is attached to this terminal plate 23C with a screw 4.
4 is screwed on.

This insulated transmission rod portion 43 extends from the end of the power fuse to a position where the camshaft 45 does not penetrate the insulating barrier 25, and has a rod 43b inside a long tube 43a.

At the tip of the insulated transmission rod portion 43, as shown in FIG. 2C, a protruding portion 43C having an angular cross-section is provided on the cylinder 43H.

One end of the protrusion 43C has a camshaft 45 on the end surface 43d.
An engagement holding member 43e bent along the circumferential surface is screwed with a screw 46.

A second
As shown in Figures a and l), there is a notch 47, and in this notch 47 there is a square prism-shaped protrusion 45 that comes into contact with the end of the rod 43b.
a is formed integrally with the camshaft 45.

The camshaft 45 is rotatably engaged and held by the inner step of the protrusion 43C and the engagement and holding member 43e.

48 is a cam attached to the camshaft 45, and this cam 48 rotates as the camshaft 45 rotates.
8 operates the microswitch 49 to notify a fuse blowout alarm.

This microswitch 49 is screwed to a mounting plate 50 having a U-shaped cross section with an L-shaped plate 51 interposed therebetween (the second
(see figure).

Next, the power fuses 23 of each phase in FIG.
It is constructed as shown in FIG. 3, which is shown in cross section along the line II-III.

In FIG. 3, an insulated transmission rod portion 43 is attached to the terminal plate 23C with a screw 44, and the inner diameter of the cylinder 43a at the end on the power fuse side gradually increases.
A sloped portion 43f is formed inside the cylinder 43a.

A ring-shaped protrusion 43g is provided at the end of the rod 43b on the terminal plate 23C side.

In the power fuse 23, an element (fuse wire) 23h is arranged inside the fuse tube 23a, and the terminal plate 23
A portion corresponding to the center of the fuse tube 23a of C is opened, and this terminal plate 23C has a cylindrical portion 23i with an inner diameter slightly larger than the opening diameter of the fuse tube 23a.
It is formed to protrude inward.

A hole 23j is bored in the center of the bottom of the cylindrical portion 23i.

Inside this cylindrical portion 23i, there is a trigger metal fitting for operation display (
A fusing indicator rod 23k is housed therein, and a spring 23l is interposed between the end of the operation indicator trigger fitting 23k and the bottom of the cylindrical part 23i.

One end of an indicator line 23m is attached to the end of the trigger fitting 23k, and the other end of the indicator line 23m is fixed to the other end of the power fuse 23 through a hole 23j.

Therefore, to explain the power fuse blowing operation, the element 23h is fused due to overcurrent, and the display line 23m is caused by the heat generated when the element 23h is blown.
For example, the rod 43b is burnt out and disconnected at the point indicated by an x mark, and the trigger fitting 23k is pushed out in the direction of the arrow by the spring 231, and the rod 43b is pushed out by the trigger fitting 23k.
is also pushed out in the direction of the arrow.

As a result, the ring-shaped protrusion 43g comes to the position shown by the dotted line and is locked on the sloped surface 43f, which is the inner surface of the tube 43a.

Rod 43b is pushed out, and rod 43b is pushed out.
The end of b rotates the camshaft 45, and the cam 48 also rotates in proportion to the rotation of the camshaft 45, which causes the microswitch 49 to operate and issue a blowout alarm.

Next, another embodiment of the present invention will be described using FIG. 4.

FIGS. 4a to 4d are a plan view, a front view, a rear view, and a side view of main parts, respectively, showing other embodiments of the present invention. Another embodiment of the rotating operation mechanism for the camshaft 45 is shown, and the other configurations are the same as in FIG. 2.

In FIG. 4, the same reference numerals are used for parts that are the same as those in FIGS. 2 and 3 or have the same functions.

In FIG. 4, the insulated transmission rod section 43 has a rod 43b inside a cylinder 43a, and the power fuse side end of the cylinder 43a constituting the insulated transmission rod section 43 has a terminal plate 23 on the power fuse 23 side. A mounting hole 61 for mounting with a screw 44 is bored in C, the inner diameter of the cylinder 43a gradually increases at the end, and a ring-shaped protrusion 43g provided at the end of the rod 43b When the fuse is blown, the rod 43b is pushed out to the left by the contact of the trigger fitting 23k, so that the rod 43b is locked at a step 62 on the inner surface on the end side of the cylinder 43a.

The outer diameter of the end of the rod 43b on the camshaft 45 side is the same as the cylinder 43.
It increases with the inner diameter of a.

A rectangular prism-shaped protrusion 45 a that comes into contact with the end of the rod 43 b on the camshaft 45 side is formed so as to protrude from the circumferential surface of the camshaft 45 integrally with the camshaft 45 .

The camshaft side end of the cylinder 43a has a protrusion 63 that protrudes downward.
A camshaft 45 is formed on the lower surface of this protrusion 63.
A retaining member 64 is bent to surround the circumferential surface of the retaining member 64 and is attached with screws 65.

The projection 45a is located at the center of the holding member 64.
A notch 66 is provided to allow movement.

Even when the insulated transmission rod portion 43 of FIG. 2 is replaced with the configuration shown in FIG. 4, the same operation as described above is performed.

That is, to explain the fuse blowout alarm operation due to the power fuse blowing, when the power fuse 23 blows, that is, the element 23h blows out, and the heat generated by this blowout causes the display line 23m to trace as shown in Fig. 3. When it burns out at the location indicated by the mark, the spring 23l causes the trigger fitting 23k to push one end of the rod 43b to the left.

Therefore, the other end of the rod 43b has a square columnar projection 4.
5a is pushed to the left, the cam shaft 45 integrated with the protrusion 45a rotates in the direction of the arrow, and along with this rotation, the cam 48
It also rotates.

This rotation of the cam 48 causes the microswitch 49 to operate and issue a fuse blowout alarm.

It goes without saying that the present invention is not limited to this embodiment, and that various applications and modifications are possible.

The present invention can be applied not only to vacuum switches but also to other electrical equipment where necessary.

As mentioned above, if the present invention is used, the following various effects can be achieved.

(1) Attach an insulated transmission rod to the end of the power fuse, as shown in FIG. Since the camshaft extends to a position where it does not penetrate the insulation barrier, the camshaft does not penetrate the insulation barrier, and the interphase distance can be sufficiently reduced.

(2) The insulated transmission rod portion allows the camshaft to be provided at a position sufficiently distant from the end of the power fuse, allowing for a large electrical insulation distance.

(3) Since the camshaft is sufficiently far away from the end of the power fuse and does not pass through the insulation barrier, assembly and disassembly are easy, and installation adjustment and replacement work when the power fuse blows out is also very easy. This results in a reduction in man-hours.

(4) The camshaft is supported at the tip of the insulated transmission rod, eliminating the need for a separate camshaft support device as shown in FIG.

[Brief explanation of the drawing]

Figures 1 a to c are a front view, plan view, and side view for explaining the main parts of a power fuse blowout alarm device in a conventional power fuse-equipped switchgear, respectively, and Figures 2 a to c are power fuses to which the present invention is applied, respectively. A front view, a plan view, and a side view for explaining the main parts of an embodiment of the present invention in a switchgear with a fuse, Part 3
The figures are an enlarged sectional view taken along the line III-III of Figure 2, and Figure 4 a.
-d is a plan view of a main part, a front view of a main part, a rear view of a main part, and a side view of a main part showing other embodiments of the present invention, respectively;
1 is a vacuum interrupter, 23 is a power fuse, 23 C
is the terminal board, 23h is the element, 231 is the trigger metal fitting (fused indicator rod), 231 is the spring, 23m is the indicator line, 25
43 is an insulating barrier, 43 is an insulation transmission rod portion, 43 a is a tube, 43 b is a rod, 43 C, 63 is a protruding portion, 43
64 is an engagement holding member, 45 is a camshaft, 45a is a protrusion, 48 is a cam, and 49 is a microswitch.

Claims (1)

[Scope of utility model registration request] At the end of the power fuse, which pushes out the blown indicator rod when the fuse blows due to the force of a built-in spring, an insulated transmission rod part having a rod that is pushed out by the blown indicator rod when the fuse blows is installed in a cylindrical shape, and the tip of the insulation transmission rod part. A cam portion for operating a microswitch is provided in the portion, and the cam shaft extends a longitudinal distance of the insulating transmission rod portion to a position where the cam shaft does not penetrate an insulating barrier for insulating each power fuse from the other. It is equipped with a microswitch that is operated by a cam part, and when the fuse blows out, the blowout indicator bar is pushed out by the spring force built into the electric power fuse, and its displacement is transmitted to the cam part via the rod of the insulation transmission rod part. A power fuse blowout alarm device characterized in that an alarm is issued by operating a microswitch.