KR20150011944A - Load break switch - Google Patents

Abstract

The present invention includes a load break switch. A load break switch (100) includes a break switch part (110) which switches a load current, a power fuse (150) which blocks an overload current and a short circuit current, and a ground switch (130) which simultaneously grounds the input terminal and the output terminal of the power fuse in opening the break switch part. The ground switch includes a fixing electrode (133) for input which is arranged between the output side of the break switch part and the input terminal of the power fuse, a first fixing electrode (135) for ground which is arranged between the input terminal of the power fuse and a ground terminal, and a second fixing electrode (137) which is arranged between the input terminal of the power fuse and the ground terminal. The fixing electrode for input, the first fixing electrode for ground and the second fixing electrode for ground are arranged in the same center axis (O). A moving electrode moves straightly along the center axis in the fixing electrode for input, the first fixing electrode for ground, and the second fixing electrode for ground, thereby allowing the state of the load break switch to be selectively changed into an input state, an opening state, and a ground state.

Description

{LOAD BREAK SWITCH}

More particularly, the present invention relates to a load switch for grounding both ends of an electric fuse installed on a secondary side of an opening and closing part and a secondary side of an opening and closing part at the time of opening the opening and closing part.

The load switch is a device that opens and closes a power system. The load switch includes a switch for opening and closing a load current of a power system and a ground switch for grounding the load on the secondary side of the switch for opening the switch. , The charge current remaining on the power cable on the load side is discharged to the earth, so that the safety of the operator in replacing the load side equipment or checking and repairing the system is promoted.

In addition, although the rated current can be opened and closed in a load switch, a large fault current such as an overload current or a short-circuit current can not be opened or closed. Therefore, an electric power fuse is also used for protecting the power system by a large current such as an overload current or a short- have.

When the power fuse is operated by the overload current or the short-circuit current on the load side, the power switch is automatically operated to stop the supply of power from the main power source to the load side.

However, even if the power fuse operates, a charge current exists in a power device, a cable, or the like of the load-side power system. In the case where a spare power source such as a self-generator is provided, Power may be supplied to the load side automatically from the backup power source. For example, if the operator approaches the power system for replacing or repairing the power fuse or for replacing or checking the load side equipment, Danger may occur.

The grounding switch functions to exclude such risks by grounding the load side power system to the ground when it is necessary to replace, check, and repair the equipment of the power fuse or load side power system.

In the case where the load switch and the ground switch are used together as described above, if there is no so-called interlock function for preventing the opening and closing portions from being simultaneously applied, the switch is turned on, If the ground switch is turned on by an operator's mistake or the like in the state that the opening / closing part is turned on and power is supplied to the load side, in some cases, it may lead to a large disaster due to a ground fault. And the load breaker having such an interlock function is disclosed in Patent Documents 1 and 2. [

However, in the technologies of Patent Documents 1 and 2, since the opening and closing part and the grounding switch each have a separate structure for performing the interlocking function in addition to the original blocking, inputting, and grounding functions, , Which leads to an increase in cost.

Also, there is a technique disclosed in Patent Document 3 as a prior art related to a load switch including an opening / closing portion, a ground switch, and a power fuse.

FIG. 1 is a diagram showing a schematic structure of a load switch of Patent Document 3. FIG.

As shown in Fig. 1, the load switch of Patent Document 3 includes a plurality of fixed conductors 10 mounted on one surface of a base plate 1 at regular intervals, and a plurality of fixed conductors 10, A driving unit 30 mounted on the side of the base plate 1 perpendicular to the row on which the movable conductor unit 20 is mounted and driving the movable conductor unit 20, A power fuse 23, and a grounding switch 5.

The grounding switch 5 is provided at one end of the base plate 1 in the direction of the movable conductor 20 and is rotatably fixed so as to be inserted or opened. And includes a pivot shaft 52 for pivoting the pivot connection base and a driving operation portion 53 for pivotally rotating the pivot shaft 52. [

In the load switch of the Patent Document 3, the open / close main body (opening / closing portion) of the load switch is inserted, the ground switch is opened, and both the open / close portion and the load switch are opened. Respectively, to the grounded state.

However, since the technology of Patent Document 3 is such that only the drawing side (load side) of the power fuse can be grounded, the drawing side of the power fuse can not be grounded, and the structure of the driving unit for switching the load switch to the closing, Is complicated and has no interlock function.

Another prior art related to a load switch including an opening / closing unit, a grounding switch, and a power fuse is disclosed in Patent Document 4.

Fig. 2 is a circuit diagram showing a schematic structure of a load switch of Patent Document 4. Fig.

2, the load switch of Patent Document 4 is connected to a break switch 12 provided between an inlet 11 to which electric power is supplied and a power fuse 13 to be in the downstream of the inlet 11, A second grounding switch 15 connected between the power fuse 13 and the transformer transformer 16 connected downstream of the power fuse 13 and connected to the ground 14, Pressure water faucet leg ratio that includes an opening and closing part 20 disposed between the power transformer 14 and the power transformer 14 and a switch 20 disposed between the power transformer 16 and the power receiving unit 40. The first and second ground switches 15 and 18 and the opening and closing part 20 and the break switch 12 are interlocked with each other so that the inlet and outlet sides of the power fuse 13 are simultaneously grounded.

However, in the load switch of Patent Document 4, the both ends of the power fuse are simultaneously grounded by the first and second grounding switches, and the opening and closing portions and the switching device opening / closing portions are operated in cooperation with the first and second grounding switches to ground the downstream device However, in order to perform the above operation, various components are connected to each other through a plurality of link mechanisms, so that the structure is complicated. Particularly, Patent Document 4 discloses that switching of the load switch to the open, There is no detailed description of how the load switch operates and how it interacts for operation.

Patent Document 1: Registration No. 10-0394025 (published on August 6, 2003) Patent Document 2: Registration No. 10-1158646 (June 26, 2012 announcement) Patent Document 3: Japanese Patent Application Laid-Open No. 10-1227614 (Announcement 2013. 1. 29) Patent Document 4: Published Patent Application No. 2010-62238 (Published on June 10, 2010)

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems of the prior art, and it is an object of the present invention to provide a power fuse for protecting a power system from an overload current and a short- And to discharge the charging current charged to the power system to the ground at the time of replacing, checking and repairing the load side equipment of the power system.

It is another object of the present invention to provide a load switch capable of selectively switching a load switch to a closing state, an open state and a grounding state by a ground switch having a simple structure.

It is another object of the present invention to provide a load switch in which an interlock function is performed at the same time by only turning on and off of the ground switch in a grounded state without the necessity of separately providing an interlock device.

According to an aspect of the present invention, there is provided a load switch including a switch for opening and closing a load current, an electric fuse for interrupting an overload current and a short-circuit current, And the ground switch selectively switches the load switch between an input state and an open state and a ground state by a single movable electrode.

Preferably, the grounding switch includes: a fixed electrode for input, which is disposed between an output side of the opening and closing unit and a lead-in end of the power fuse; and a first grounding fixed electrode disposed between the lead- And a second fixed electrode for grounding disposed between the leading end of the power fuse and the ground terminal, wherein the first fixed electrode for grounding, the second fixed electrode for grounding, and the second fixed electrode for grounding have the same center axis And the movable electrode moves linearly along the central axis in the input fixed electrode, the grounding first fixed electrode, and the grounding second fixed electrode so that the load switch is placed in the closed state, State.

Preferably, the input fixed electrode and the grounded first fixed electrode each include a pair of contacts spaced apart in the central axis direction, and the movable electrode has a conductive portion formed in a part of the longitudinal direction , The conductive portion includes a large diameter portion having a large diameter and a small diameter portion having a diameter smaller than that of the large diameter portion, and in the closing state, the large diameter portion is electrically connected to the pair of contacts of the charging fixed electrode The large diameter portion is electrically connected to the pair of contacts of the first grounding fixed electrode, and the small diameter portion is electrically connected to the second grounding second fixed electrode.

Preferably, the input fixed electrode and the grounding first fixed electrode each further include a plurality of springs for applying a restoring force to the pair of contacts, A restoring force is applied to the pair of contacts in a state of being electrically connected to the grounding first fixed electrode and the electrical connection between the large diameter portion and the first inputting fixed electrode or the first grounding electrode is released The restoring force is restored to the original position of the pair of points.

Preferably, the pair of contacts of the input fixed electrode and the grounding first fixed electrode has a recess having a shape corresponding to the shape of the outer peripheral surface of the movable electrode in a direction perpendicular to the central axis, The movable electrode moves linearly in the recess.

The load switch of the present invention having the above configuration can selectively operate between the closing state of the grounding switch, the open state and the grounding state only by moving the moving electrode in the direction of the center axis of the movable electrode. The load switch can be selectively switched between the input state, the open state, and the ground state.

In addition, the load switch of the present invention can be used when the load side of the power system including the power fuse and equipment are replaced, inspected and maintained in a state where the opening / The charging current charged in the electric power system is discharged to the ground, so that the safety of the operator can be achieved.

Further, since the load switch of the present invention can be selectively switched between the closing state, the open state and the grounding state of the ground switch by only moving the movable electrode made of a single body in the direction of the central axis, it is possible to provide a separate interlock device It is possible to provide a load switch in which the interlock function is simultaneously performed by only the closing and opening operation of the ground switch in the grounded state without the necessity.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a schematic structure of a prior art load switch,
2 is a diagram showing a schematic structure of another prior art load switch,
Fig. 3 is a cross-sectional view showing a main structure of a load switch of a preferred embodiment of the present invention, in which the opening and closing parts of the load switch are put in and the ground switch is opened,
Fig. 4 is a cross-sectional view showing a main structure of a load switch of a preferred embodiment of the present invention, which shows an open state in which both an opening and closing part of a load switch and a ground switch are opened;
5 is a cross-sectional view showing the main structure of a load switch of a preferred embodiment of the present invention, in which the opening and closing part of the load switch is opened and the ground switch is grounded,
6 is a view showing the detailed structure of the movable electrode,
7 is an exploded perspective view showing a detailed structure of the immovable fixed electrode.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

3 is a cross-sectional view showing a main structure of a load switch according to a preferred embodiment of the present invention. Fig. 3 is a cross-sectional view showing a state where the opening / closing part 110 of the load switch 100 is turned on and the ground switch 130 is opened 4 shows an open state in which both the opening and closing part 110 of the load switch 100 and the ground switch 130 are opened and FIG. 5 shows a state in which the opening and closing part 110 of the load switch 100 is open, (130) indicates a grounded state. 6 is a diagram showing the detailed structure of the movable electrode 131, and Fig. 7 is an exploded perspective view showing the detailed structure of the immovable fixed electrode 133. Fig.

3, the load switch 100 according to the present embodiment includes a case 170, an opening / closing part 110 disposed at a predetermined position inside the case 170, a ground switch 130, and a power fuse 150).

The case 170 has a shape suitable for accommodating the opening and closing part 110, the ground switch 130 and the power fuse 150 and has a conductive part for electrically connecting each part and a fixed electrode 133 for charging, Except for a necessary portion such as a portion where the first fixed electrode 135 is disposed, is made of an epoxy resin. Here, the kind of the epoxy resin is not particularly limited, and any known epoxy resin for solid insulation may be used.

The opening and closing part 110 opens and closes the power system to supply or cut off electric power supplied from the main power supply to the customer side, for example, between a main power supply such as a power company and a load such as a customer, Although it is possible to open and close the current, the overload current or the short-circuit current can not be opened or closed. Although not shown in detail in FIG. 3, the structure includes electrodes for opening and closing the supply of electric power.

As the opening and closing part 110, various known circuit-breakers may be used, and the opening and closing part 110 is not a subject of the present invention, and a detailed description thereof will be omitted.

Further, on the drawing side of the power fuse 150, for example, a substation including a transformer is disposed, if necessary, and these are not the subject of the present invention, and a detailed description thereof will be omitted.

The ground switch 130 is disposed between the output side of the opening and closing part 110 and the pulling side of the power fuse 150 and has a function of switching the load switch 100 to three states of closing, do.

The ground switch 130 is provided between the output terminal of the opening and closing unit 110 and the input terminal of the power fuse 150 and between the input terminal of the power fuse 150 and the ground terminal G, A first fixed electrode 135 for grounding disposed on the same center axis O as the input fixed electrode 133 and a second fixed electrode 135 for grounding between the lead terminal of the power fuse 150 and the ground terminal G, A second fixed electrode 137 for grounding disposed on the same central axis O as the grounding first fixed electrode 135 and the fixed electrode 133 for input having the same central axis O, A first fixed electrode 135 for grounding and a second fixed electrode 137 for ground and mechanically connected to a driving mechanism not shown to interfere with the driving mechanism for inputting fixed electrodes 133, And a movable electrode 131 that linearly moves within the first fixed electrode 135 for grounding and the second fixed electrode 137 for grounding.

In this embodiment, the fixed electrodes are arranged in the order of the grounding second fixed electrode 137, the grounding first fixed electrode 135, and the grounding fixed electrode 133 with respect to the grounding end G, Each of the fixed electrodes is disposed on the same axis as the central axis O.

One end of the immovable fixed electrode 133 is electrically connected to the output terminal of the opening and closing unit 110 and the other end is electrically connected to the input terminal of the power fuse 150 and the first fixed electrode 135 for grounding. The grounding first fixed electrode 135 is electrically connected to the inlet end of the power fuse 150 and the other end of the charging fixed electrode 133. The grounding second fixed electrode 137 is electrically connected to one end And is electrically connected to the lead terminal of the fuse 150 and the other end is electrically connected to the ground terminal G. [

3 and the like, the second fixed electrode 137 for grounding is constituted by a pair of electrodes 1371 and 1372 arranged in a line in the direction of the center axis O of the ground switch 130 . Details of the charging fixed electrode 133 and the first grounding fixed electrode 135 will be described later.

The electrical connection between each of the fixed electrodes and the output terminal of the switching unit 110 and between the lead-in terminal and the lead-in terminal G of the power fuse 150 can be achieved by using a known appropriate method such as using a bus bar .

Next, a detailed configuration of the movable electrode 131 will be described with reference to Fig.

6, the movable electrode 131 has a cylindrical shape and includes a conductive portion 1311 made of a conductive material and located near a substantially central portion in the longitudinal direction of the movable electrode 131, And an insulating portion 1313 formed at both ends of the insulating layer.

The conductive portion 1311 is selectively brought into contact with the pair of contact points 1332 and 1332 of the input fixed electrode 133 or the first grounded fixed electrode 135 by a linear movement of the movable electrode 131 A large diameter portion 1311a having a relatively large diameter and a small diameter portion 1311b having a relatively small diameter as compared with the large diameter portion 1311a.

The insulating portion 1313 includes a first insulating portion 1313a having one end coupled to one end of the large diameter portion 1311a of the conductive portion 1311 and having a diameter smaller than that of the large diameter portion 1311a, And a second insulating portion 1313b which is coupled to one end of the small-diameter portion 1311b and has a diameter substantially equal to that of the small-diameter portion 1311b.

The other end of the first insulating portion 1313a of the insulating portion 1313, that is, the opposite end of the side that engages with the large-diameter portion 1311a mechanically engages with a ground switch driving mechanism (not shown) The movable electrode 131 is moved in the first fixed electrode 135 for grounding and the second fixed electrode 137 for grounding, that is, in the grounding switch 130 of the grounding switch 130, And linearly moves along the center axis O of the switch 130. [

In this embodiment, the diameters of the respective portions of the movable electrode 131 are set to have the relationship of "large diameter portion 1311a> first insulating portion 1313a> small diameter portion 1311b = second insulating portion 1313b" The diameter of the large-diameter portion 1311a may be set to a relatively large value as compared with the other portions, and the first insulating portion 1313a and the small-diameter portion 1311b and the second insulating portion 1313b May have the same or different diameters.

The length of the large diameter portion 1311a of the movable electrode 131 is set to be longer than the length of the contact 1332 of the input fixed electrode 133 and the grounding first fixed electrode 135 in the direction of the center axis O (See Figs. 3 and 5).

The entire length of the conductive portion 1311 of the movable electrode 131 is set such that the large diameter portion 1311a of the conductive portion 1311 of the movable electrode 131 is connected to the grounding switch 130 when the ground switch 130, 1 contact with the contact 1332 of the fixed electrode 135 and at least a part of the small diameter portion 1311b is moved in the direction of the central axis O of the grounding switch 130 of the second grounding second fixed electrode 137 And a pair of electrodes 1371 and 1372 arranged so as to be electrically connected to each other (see Fig. 5)

Next, a detailed configuration of the immovable fixed electrode 133 will be described with reference to FIG.

The input fixed electrode 133 is housed in the housing 1331 and provides the moving path of the movable electrode 131 described above and at the same time when it contacts the large diameter portion 1311a of the movable electrode 131 A pair of contacts 1332 and 1332 which form a conductive passage to be described later with the large diameter portion 1311a in the backward direction, a pair of guide rings 1334 that guide the backward movement of the contact 1332, A pair of guides 1335 which are arranged inside the guide ring 1334 so that the backward movement of the contact 1332 becomes a linear movement and a pair of contacts 1335 which are disposed inside the guide ring 1334 when the force for moving the pair of contacts 1332, A plurality of return springs 1336 for returning the pair of contacts 1332 and 1332 to a position before the reverse and a pair of contacts 1332 and 1332, a guide ring 1334, a guide 1335, And a pair of caps 1333 for accommodating the spring 1336 in the housing 1331 and closing both ends of the housing 1331. [

The housing 1331 is made of an insulator and has a cylindrical shape and corresponds to the position of the pair of contacts 1332 and 1332 in a direction substantially perpendicular to the longitudinal direction of the housing 1331 at a substantially central portion of the housing 1331 And the pair of contacts 1332 and 1332 are formed in a circular opening 1331a at a predetermined distance from the center of the circular opening 1331a, As shown in FIG.

A screw for coupling the cap 1333 is formed on both ends of the inner circumferential portion of the housing 1331 so that the pair of contacts 1332 and 1332 are engaged with the screw formed on the outer circumferential portion of the cap 1333, Both ends of the housing 1331 are closed to receive the guide ring 1334 and the guide 1335 in the housing 1331. [

In this embodiment, the housing 1331 and the cap 1333 are coupled to each other by screw engagement. However, the present invention is not limited to this, and may be combined using other known methods such as welding.

The contacts 1332 are made of a conductive material and the pair of contacts 1332 and 1332 are arranged to face each other within the housing 1331 at a predetermined distance d from the center of the opening 1331a.

The one surface of the contact 1332 facing the other of the pair of contacts 1332 and 1332 has a generally planar shape and is formed at its center with a substantially semicircular shape so as to correspond to the shape of the movable electrode 131 Shaped movable electrode 131 can smoothly move linearly within the pair of contacts 1332 and 1332 by the concave portion.

A projecting portion 1332a projecting in a circumferential direction protrudes in the longitudinal direction of the housing 1331 on the other side of the contact 1332, that is, on the side opposite to the side where the pair of contacts 1332 and 1332 face each other, 1332a are inserted into the guide 1335 of the guide ring 1334 to stably guide the linear motion when the contact 1332 is returned and returned to the home position.

The distance d between the pair of contacts 1332 and 1332 is slightly smaller than the diameter D of the large diameter portion 1311a of the conductive portion 1311 of the movable electrode 131 and the other first insulation portion 1313a , The diameter of the small diameter portion 1311b, and the diameter of the second insulating portion 1313b. When the large diameter portion 1311a of the movable electrode 131 contacts the contact 1332 in the course of the linear movement of the movable electrode 131 along the center axis O of the ground switch 130, 1332 and 1332 move backward in the direction away from each other and the contact 1332 does not come in contact with the other portions, that is, the first insulating portion 1313a, the small diameter portion 1311b and the second insulating portion 1313b, I never do that.

The guide ring 1334 is made of a cylindrical conductive material having one side closed and a cylindrical guide 1335 made of a conductor is accommodated in the inside of the cylinder and the protrusion 1332a of the contact 1332 is inserted into the guide 1335, So that the linear motion of the contact 1332 is firmly guided.

The guide 1335 is provided with a guide (not shown) so as to stably maintain the contact state between the large diameter portion 1311a of the movable electrode 131 and the pair of contacts 1332 and 1332 by ensuring accurate linear movement of the contact 1332. [ The inner diameter r of the contact 1332 is set to a value slightly smaller than the outer diameter R of the protrusion 1332a of the contact 1332 and the protrusion 1332a of the contact 1332 Is moved into the guide 1335, the diameter is enlarged. On the contrary, when the contact 1332 returns to the original state, the diameter is restored to its original diameter.

To this end, a plurality of large-diameter segments 1335a are arranged so as to overlap each other in the circumferential direction of the inner circumferential side of the guide 1335, as shown in the circle of Fig. 7, which is an enlarged view of the guide 1335, A return spring 1335b is disposed between the plurality of diameter segments 1335a and the diameter segments 1335a.

With this configuration, when the protruding portion 1332a having the relation of the outer diameter R of the protruding portion 1332a to the inner diameter r of the guide 1335 moves to the inner circumferential side of the guide 1335, The protruding portion 1332a of the contact 1332 is held in the guide 1335 in a state in which the protruding portion 1332a of the contact 1332 is rigidly supported by pushing out the one end of the plurality of the large diameter segments 1335a, So that the pair of contacts 1332 and 1332 maintain a firm contact with the large diameter portion 1311a of the movable electrode 131. As a result,

The first fixed electrode 135 for grounding has the same configuration as that of the input fixed electrode 133 described above and the difference from the input fixed electrode 133 is that the input fixed electrode 133 is connected to the output terminal Since the grounding first fixed electrode 135 is an electrode which opens and closes between the input terminal of the power fuse 150 and the ground terminal G, A detailed description thereof will be omitted.

As described above, the second fixed electrode for grounding 137 opens / closes between the lead terminal of the power fuse 150 and the ground terminal G, and is connected to a pair of grounding switches 130 arranged in the direction of the central axis O of the ground switch 130 And electrodes 1371 and 1372 of FIG.

3, the electrode 1371 of the pair of electrodes 1371 and 1372 is connected to the lead terminal of the power fuse 150, the electrode 1372 is connected to the ground terminal G, The shapes and functions of the movable electrodes 131 and 1372 are the same as those of the guide 1335 of the immovable fixed electrode 133. The movable electrodes 131 and 1372 move linearly in the direction of the central axis O of the movable electrode 131, 131 are electrically connected to the electrode 1371 and the electrode 1372 at the same time, the lead terminal of the power fuse 150 and the ground terminal G are electrically connected to each other.

The inside diameter of the second grounding second electrode 137 is slightly smaller than the small diameter portion 1311b and the second insulating portion 1313b of the movable electrode 131, The second insulating portion 1313b and the second insulating portion 1313b are linearly moved in the direction of the central axis O in a state where they are firmly supported in the pair of electrodes 1371 and 1372 of the grounding second fixed electrode 137 .

The power fuse 150 is for protecting the load switch 100 from an overload current or a short-circuit current flowing on the customer side, that is, the load side, and the lead- And is electrically connected to the first fixed electrode 135 for grounding. The lead terminal is electrically connected to the load side, and at the same time, the second fixed electrode 137 for grounding of the ground switch 130 And is electrically connected to the electrode 1371.

3 and the like, the end of the ground switch 130 is directly grounded. However, in reality, the end of the ground switch 130 may be grounded via a ground cable or a bus bar or the like , Or may be grounded by any other method.

In the present invention, the opening / closing unit 110 can be opened and closed by a manual operation of the user when necessary for replacing a transformer, a power fuse, or the like in a load-side power system, When the power fuse 150 is operated by the power fuse 150 and the converter is opened, the power fuse 150 may be opened automatically in conjunction with the operation of the power fuse 150.

As described above, one end of the movable electrode 131 of the grounding switch 130 is mechanically connected to the grounding switch 130 driving mechanism (not shown), and the grounding switch 130 driving mechanism Alternatively, the movable electrode 131 may be automatically provided with a motor or the like. Also, when the movable electrode 131 is automatically driven, the movable electrode 131 is electrically driven by operating the operation button, for example, by a motor only method, so that the ground switch 130 is turned on and off And may be switched to the ground state via the opening state of the opening / closing unit 110 or the opening state of the power fuse 150 automatically in conjunction with the operation of the power fuse 150. [

Next, the operation of the load switch 100 of the present embodiment will be described.

First, the charging state will be described with reference to FIG.

3, when the load switch 100 is in the closed state, the open / close unit 110 is in the closed state (ON state), and power is supplied from the main power supply such as the power company to the customer, The switch 130 is turned on when the large diameter portion 1311a of the movable electrode 131 is brought into contact with the pair of the input fixed electrodes 133 by the driving of the ground switch 130 driving mechanism The contacts 1332,

The output terminal of the opening and closing part 110 is connected to the pair of contacts 1332 and 1332 of the charging fixed electrode 133 of the grounding switch 130 and the large- The power supply fuse 150 is electrically connected to the input terminal of the power fuse 150 via the power fuse 150 and the power supplied from the main power supply is supplied to the load side of the consumer through the power fuse 150. [

Next, the opening state of the ground switch 130 will be described with reference to Fig.

Following the opening of the opening and closing part 110 in conjunction with the opening of the opening and closing part 110 or the operation of the power fuse 150, the movable electrode 131 Is moved in the opening direction of the grounding switch 130 (downward direction in the figure), the movable electrode 131, which is in contact with the pair of contacts 1332 and 1332 of the input fixed electrode 133, The large diameter portion 1311a of the large diameter portion 1311a of the movable electrode 131 is released from the contact state so that the large diameter portion 1311a of the movable electrode 131 can be fixed to either the charging fixed electrode 133 or the first grounding fixed electrode 135 So that the electrode is not in electrical contact with the electrode.

4 shows a state in which the small diameter portion 1311b of the movable electrode 131 is electrically connected to the electrode 1371 of the second grounding fixed electrode 137. The small diameter portion 1311b of the movable electrode 131, The first fixed electrode 1311b may not be in contact with the electrode 1371 of the grounding second fixed electrode 137. An important point in the open state is that the electric current supplied from the main power supply to the load side of the consumer is also open The load side of the customer is not grounded via the ground terminal G. [

Next, the grounding state of the grounding switch 130 will be described with reference to Fig.

The movable electrode 131 further moves (further moves downward in FIG. 5) by driving the ground switch 130 driving mechanism (not shown) and the large diameter portion 1311a of the movable electrode 131 is fixed to the first fixed The small diameter portion 1311b comes into contact with the pair of contacts 1332 and 1332 of the electrode 135 and the small diameter portion 1311b electrically connects the contact 1371 of the second grounding second electrode 137 and the contact 1372 The input end of the power fuse 150 is electrically connected to the ground terminal G through the pair of contacts 1332 and 1332 of the first fixed electrode 135 and the large diameter portion 1311a of the movable electrode 131, And the leading end of the power fuse 150 is connected to the contact 1371 of the second fixed electrode 137 for ground and the small diameter portion 1311b of the movable electrode 131 and the second fixed electrode 137 for ground And is electrically connected to the ground terminal G via the contact 1372. This state is a ground state of the ground switch 130. [

When the ground switch 130 is grounded, the load side of the load switch 100 is grounded, and the charging current in the power system on the load side is discharged to the ground by the ground.

In addition, even if the emergency power source such as a self-generator installed on the customer side for some reason is activated, the worker who performs the replacement, inspection, and repair of the load side equipment by stopping the operation of the emergency power source by the ground on the load side, So that it can be safely protected from danger.

The load switch 100 according to the present embodiment having the above-described configuration and operation can be switched between the closed state of the ground switch 130 and the opened state of the ground switch 130 only by the movement of the movable electrode 131 in the direction of the center axis O, And the ground state, so that the load switch can be selectively switched to the closing state, the open state and the grounding state by a simple structure.

In addition, the load switch 100 of the present embodiment is grounded at the same time as the lead-out side of the power fuse as well as the lead-in side of the power fuse so that the load side equipment and equipment of the power system including the power fuse The charge current charged in the power system can be released to the ground at the time of inspection and maintenance, thereby assuring the safety of the operator.

The load switch 100 according to the present embodiment can be selectively switched between the closed state of the ground switch 130 and the grounded state by only moving the movable electrode 131 in the direction of the center axis O, It is possible to provide a load switch in which an interlock function is simultaneously performed by only the closing and opening operation of the ground switch in the grounded state without the necessity of providing a separate interlock device.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. For example, the following modifications are possible.

Although the solid state insulation type load switch has been described as an example in the above embodiments, the insulation type is not limited to the solid insulation type. For example, other methods such as air insulation, vacuum insulation, gas insulation, And these methods may be combined. For example, the power fuse may be disposed in the air in a manner of combining a plurality of insulation systems, and the opening and closing unit may be an insulation system such as a vacuum insulation system or a gas insulation system. It is obvious to those who have knowledge.

In the above embodiment, the opening / closing part, the ground switch and the power fuse are accommodated in a single case. However, the opening / closing part, the ground switch and the power fuse may be accommodated in separate cases, Two of them may be housed in one case and the rest may be housed in a separate case.

In the above embodiment, the load switch is arranged in the order of the opening / closing part, the earthing switch, and the power fuse in this order from the side of the main power supply. However, the present invention is not limited thereto and the position of the opening and closing part and the power fuse may be reversed.

In the above embodiment, the ground switch is arranged in the order of the input fixed electrode, the grounding first fixed electrode, and the grounding second fixed electrode. However, the arrangement order is not limited to this, It may be arranged in a different order as far as it has a structure in which both ends of the power fuse are simultaneously grounded at the time of opening the opening and closing part while being able to selectively operate the load switch as the motion between the input state, the open state and the ground state.

The length relationship between the movable electrodes described in the above embodiments is not limited to the above-described embodiment. The lengths of the movable electrodes, the grounding first fixed electrodes and the grounding second fixed electrodes, It can be set appropriately as long as it is an ordinary technician.

The present invention may be carried out by the constructions described in the above embodiments, or by combining the above embodiments with the above modifications.

100 load switch 110 opening /
130 Grounding switch 150 Power fuse
131 movable electrode 1311 conductive portion
1311a large-diameter portion 1311b small-
1313a First insulation part 1313b Second insulation part
133 Fixed electrode for input 1331 Housing
1332 contacts 1333 cap
1334 Guide Ring 1335 Guide
1336 spring 135 first fixed electrode for grounding
137 grounding second fixed electrode

Claims (5)

With a load switch,
An opening and closing unit for opening and closing the load current,
A power fuse for interrupting an overload current and a short-circuit current,
And a ground switch for simultaneously grounding the lead terminal and the lead terminal of the power fuse when the opening / closing part is opened,
Wherein the ground switch selectively switches the load switch between an input state and an open state and a ground state by a single movable electrode. The method according to claim 1,
The ground switch includes:
A fixed electrode for input which is disposed between an output side of the opening / closing part and a pulling end of the power fuse,
A first grounding fixed electrode disposed between an input terminal of the power fuse and a ground terminal,
And a grounding second fixed electrode disposed between the leading end of the power fuse and the grounding end,
The input fixed electrode, the grounding first fixed electrode, and the grounding second fixed electrode are arranged on the same central axis,
Wherein the movable electrode linearly moves along the center axis in the input fixed electrode, the grounding first fixed electrode, and the grounding second fixed electrode so that the load switch is selectively switched between an open state and an open state and a ground state Load switch. The method of claim 2,
Wherein the input fixed electrode and the grounded first fixed electrode each have a pair of contact points spaced apart from each other in the central axis direction,
Wherein the movable electrode has a conductive portion formed in a part of the longitudinal direction,
The conductive portion includes a large diameter portion having a large diameter and a small diameter portion having a diameter smaller than that of the large diameter portion,
The large diameter portion is electrically connected to the pair of contacts of the charging fixed electrode in the charging state,
Wherein the large diameter portion is electrically connected to the pair of contacts of the first grounding fixed electrode and the small diameter portion is electrically connected to the second grounding second fixed electrode. The method of claim 3,
Wherein the input fixed electrode and the grounded first fixed electrode each further include a plurality of springs for applying a restoring force to the pair of contacts,
Wherein the spring applies a restoring force to the pair of contacts when the large diameter portion is electrically connected to the input fixed electrode or the grounding first fixed electrode, The first pair of fixed electrodes are restored to their original positions by the restoring force when the electrical connection between the first fixed electrodes is released. The method of claim 3,
The pair of contacts of the input fixed electrode and the grounding first fixed electrode has a recess having a shape corresponding to the shape of the outer peripheral surface of the movable electrode in a direction perpendicular to the central axis,
And the movable electrode moves linearly in the recessed portion.

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