JPH035066Y2 - - Google Patents

Description

[Detailed description of the invention] Purpose of the invention (industrial application field) This invention relates to an air switch with a current limiting fuse,
More specifically, the present invention relates to an air switch with a current-limiting fuse that allows easy grounding work during maintenance and inspection.

(Prior art) In general, in high-voltage power receiving equipment that uses this type of switch as the main breaker, when performing maintenance and inspection on various circuits lower than the main breaker, safety is taken into account and the load-side bus bar is The work was carried out by attaching grounding devices to each phase.

(Problems to be solved by the invention) However, this grounding device is expensive and requires the worker to install and remove it during the above-mentioned work, which is not only very troublesome but also poses a risk of forgetting to ground the device. It was hot too.

This invention solves the above-mentioned problems and provides an air switch with a current-limiting fuse that prevents malfunctions (closing rotations), allows the maintenance and inspection to be performed safely and easily, and saves time. It is in.

Structure of the device (means for solving the problem) This device fixes a pair of upper and lower support insulators to the mounting base that constitutes the machine frame, and provides a fixed electrode on the upper support insulator, and a limited number of support insulators on the lower support insulator. A fuse support stand equipped with upper and lower fuse clamping fittings that clamps both ends of the current-limiting fuse is provided, and is electrically connected to the current-limiting fuse, and is turned on and opened via an opening/closing mechanism by rotation of the operating shaft. In a current limiting fuse air switch in which a movable contact blade is connected to and separated from the fixed electrode, the grounding fixed electrode is arranged below the lower support insulator of each phase and insulated from the machine frame. are fixed, the grounding fixed electrodes of the same phases are electrically connected to each other, and electrically connected to the machine frame via a connecting member connectable to the machine frame, and the base end of the movable contact blade is A grounding movable electrode is extended to contact the grounding fixed electrode after the movable contact blade is released when the opening operation is performed, and the grounding movable electrode is rotatably supported on the machine frame and is in the locked position. A closing prevention lever that restricts the rotation of the operation shaft in the closing direction, a tension spring that is hung on the closing prevention lever and biases and holds the closing prevention lever in a locked position, and a tension spring that is connected to and separated from the closing prevention lever. The gist of the present invention is to provide a locking mechanism having a locking plate which is disposed so as to be able to engage the closing prevention lever and holds the closing prevention lever in the locked position in the non-released position where the closing prevention lever is engaged.

(Function) With the above configuration, when the movable contact blade of the present current limiting fuse switch, which is the main interrupting device of the power receiving equipment, is opened by the opening/closing mechanism, after the movable contact blade is opened, the base end of the movable contact blade is opened. The grounding movable electrodes provided on the grounding electrodes are connected all at once to the grounding fixed electrodes,
Various circuits below the switch of the present application are automatically grounded. Furthermore, the lock mechanism prevents malfunction (turning of the operating shaft).

(Embodiment) An embodiment embodying this invention will be described below with reference to FIGS. 1 to 8.

The machine frame K is composed of a mounting base 1 which is bent so that the front surface thereof protrudes into a mountain shape, and a pair of fixed frames 2 and 3 having an L-shaped cross section and fixed to the left and right sides of the mounting base 1. ing. An upper support insulator 4 for each phase is attached to the upwardly inclined surface of the mountain-shaped portion of the mounting base 1, and a bolt 5 is attached at the base end.
At the same time, lower support insulators 6 for each phase are arranged in a V-shape with respect to each of the upper support insulators 4 on the downwardly inclined surface of the mountain-shaped portion at the base end. It is fixed with bolts 7.

An arc extinguishing chamber 8 is fixed at the tip of the upper support insulator 4, and a fixed interposed electrode 9 is fixedly installed inside the arc extinguishing chamber 8. Power supply side terminal 10 led out upward from arc chamber 8
is connected.

As shown in FIG. 2, a vertically extending fuse support base 11 is integrally formed at the tip of the lower support insulator 6 in an oblique shape so that its lower end is inclined toward the support insulator 6 side from its upper end. . Upper and lower fuse clamping fittings 12 and 13 are fixed to the upper and lower ends of the fuse support 11, respectively. A load-side connection terminal 14 led out downward is connected and fixed to the lower fuse holding fitting 13.

As shown in FIG. 1, a projection 11a is provided on one side of the fuse support base 11 from the center to the upper end.
A lower end portion of a movable contact blade 16, which corresponds to the protrusion portion 11a so as to be able to approach and separate from the fixed insertion electrode 9, is rotatably supported by a shaft 16a. The upper end portion of a conductive plate 17, which also constitutes a terminal plate, is connected to the upper surface of the base end of the upper fuse holding fitting 12 in an overlapping manner.

Further, from one side of the lower end of the conductive plate 17, a connecting portion 17a is connected.
is bent and extended to a position where it is inserted into the shaft 16a, and is fixed between the lower end of the movable contact blade 16 and the protrusion 11a, and is electrically connected to the movable contact blade 16.

A driven lever 18 is pivotally supported at the center of the upper end of the fuse support base 11 so as to be rotatable. One end of a connecting rod 19 constituting a part of an open-phase prevention mechanism is fixed to the upper end of the driven lever 18, and a blowout display device Fa for a current-limiting fuse F connected between the fuse clamping fittings 12 and 13 is attached. When the driven lever 18 is rotated in response to the protruding operation, the movable contact blades 16 of each phase are simultaneously opened via the open-phase prevention mechanism.

Further, one end of a push-up rod 20 made of an insulating material such as synthetic resin and forming a part of the opening/closing mechanism is rotatably attached to the center of the movable contact blade 16. By operating an operating shaft 21 rotatably installed between the lower portions 2 and 3 of both fixed frames with an operating handle 22 fixed to its right end, the Movable contact blade 1
6 is rotated to open and close, and the operating handle 22 is engaged with the closing lock release lever 50 against the tensile force of a release spring (not shown) suspended between the operating shaft 21 and the inner surface of the mounting base 1. It is designed to configure the input state.

On the lower surface of the mounting base 1, a plate-shaped common support fitting 24 is provided with bolts 25 made of an insulating material such as synthetic resin in the left and right direction via an insulating plate 23 so as to span each phase.
It is fixed at. Therefore, this common support fitting 24 is insulated from the mounting base 1.
Fixed electrodes 26 for grounding, which correspond to each movable contact blade 16 and consist of a clamping bracket 26a and an auxiliary bracket 26b that clamps the clamping bracket 26a from the outside, are fixed to the common support bracket 24 with screws. . One end of the ground line L is connected to the left end of the common support fitting 24 with the bolt 25, and the other end of the ground line L is removably bolted to the downwardly inclined surface of the mounting base 1.

A long plate-shaped grounding movable electrode 27 is extended from the base end of the movable contact blade 16, and the movable contact blade 16 is rotated in the opening direction and separated from the fixed insertion electrode 9. After the interruption is completed, it comes into contact with the grounding fixed electrode 26.

A locking lever 28 is fixed to a projecting end of the operating shaft 21 that projects leftward from the fixed frame 2. A latching pin 29 protrudes from the upper base end of the latching lever 28 and extends toward the fixed frame 2 side. Further, a closing prevention lever 30 is provided at a position above the operating shaft 21 in the fixed frame 2.
is rotatably supported, and its pivot point G
A stopper 30a is provided on the outer surface of the fixed frame 2 slightly above the stopper 30a, and is adapted to restrict the amount of rotation of the closing prevention lever 30 in the clockwise and counterclockwise directions.

Further, a spring latch piece 31 is fixedly attached to the outer surface of the fixed frame 2 slightly below the pivot point G of the closing prevention lever 30, and the tip of the spring hook piece 31 and the center of the closing prevention lever 30 are fixedly attached. A tension spring 32 is hung between the parts. The tension spring 32 locks the closing prevention lever 30 to the stopper 30a at the line X connecting the latching position of the hand tension spring 32 to the spring locking piece 31 and the pivot point of the closing prevention lever 30 by its biasing force. It is designed to be selectively positioned between a locked position and an unlocked position.

A hook portion 30b is formed at the distal end of the injection prevention lever 30 so as to curve upward, and a latching protrusion 33 and an engaging protrusion 34 are provided downwardly at the lower part of the base end and the lower part of the substantially central part. . Said latching protrusion 3
3, when the closing prevention lever 30 is in the locked position and the lock plate 35 (described later) is normally located in the unlocked position due to its own weight, the operating shaft 21 moves from the closing state to the opening direction (P When the locking pin 29 of the locking lever 28 is rotated in the direction of the arrow Q, the locking pin 29 of the locking lever 28 comes into contact with the inner surface 33a of the locking protrusion 33, and the closing prevention lever 30 is rotated in the direction of the arrow Q against the biasing force of the tension spring 32. Before the tension spring 32 crosses the line (See Figure 7).

Further, when the operation shaft 21 is rotated from the open state in the closing direction as shown in FIG. 7 when the closing prevention lever 30 is in the locked position, the locking protrusion 33 locks the locking pin 29 of the locking lever 28. is latched to prevent the operating shaft 21 from being rotated.

A lock plate 35 is provided at a position below the input prevention lever 30 on the outer surface of the side wall of the fixed frame 2.
is provided. That is, the lock plate 35 has an elongated hole 35a extending in the vertical direction, and is inserted through the elongated hole 35a and is inserted into the fixed frame 2.
It is slidably attached to a screw 36 that is screwed into the screw 36, and can move up and down within the range allowed by the elongated hole 35a.

The upper end of the locking plate 35 is formed with an abutting part 37 that engages with the front part of the engagement protrusion 34 of the closing prevention lever 30 in the locked position to hold it in the locked position, and the locking plate 35 is in the upper position (i.e., in the non-locking position). Q of the closing prevention lever 30 when held in the release position)
It is designed to prevent rotation in the direction of the arrow.
Further, when the lock plate 35 is held at the lower position (that is, the release position), the abutment portion 37 is separated from the engagement protrusion 34 and positioned at the lower side, preventing the rotation of the closing prevention lever 30 in the counterclockwise direction. It is in an unlocked state that allows.

At the lower ends of the lock plate 35 and the fixed frame 2, transparent hook holes 38 and 39 are formed in correspondence with each other.
By locking the lock 40 in the locking holes 38 and 39, the lock plate 35 is placed in the upper position (that is, the non-released position).
When the lock 40 is not engaged, it always falls to a downward position due to its own weight. Further, the central portion of the lock plate 35 extends forward, and a display plate 41 is integrally provided at the tip of the extending portion so as to be orthogonal thereto.

There are "grounding locks" at the top and bottom of the front of the display board 41.
and "Unlocked" are displayed. The display plate 41 can be moved up and down by a cover plate 2a bent into an L-shape at the front of the lower end of the fixed frame 2, depending on whether the locking plate 35 is in the locked or unlocked state of the closing prevention lever 30. It is designed so that one of the sections is covered and the display of the other section is displayed.

A lock mechanism A is constituted by the closing prevention lever 30, the tension spring 32, and the lock plate 35.

Note that the machine frame K is grounded by a grounding wire (not shown).

The operation of the switch configured as described above will be explained.

Now, FIG. 3 and FIG. 5 show the switch in the closing state, and as shown by the solid line, the lock plate 35 has its abutting portion 37 separated from the front part of the engagement protrusion 34 of the closing prevention lever 30, and the closing prevention lever 30 is closed. 30 is in the lock position. At this time, as shown in FIG.
The display board 41 of No. 5 has a "grounding lock" at the top of its front surface.
The display is hidden behind the cover plate 2a, and the "unlock" display at the bottom of the front is visible. Further, as shown in FIG. 1, the common support fitting 24 is grounded via a grounding wire L connected to the mounting base 1.

When the closing lock release lever 50 is rotated clockwise from this state, it is disengaged from the operating handle 22, and the operating shaft 21 is rotated in the direction of the arrow P by the tensile force of the release spring (not shown). This drives the opening/closing mechanism and opens the movable contact blade 16 which is in the closed state. As a result, after the movable contact blade 16 has been completely opened, the grounding movable electrode 27 is brought into pinch contact with the grounding fixed electrode 26 for all phases at the same time, and the lower circuit of this switch is automatically grounded. (See Figure 4).

On the other hand, when the operating shaft 21 is rotated in the direction of arrow P,
Since the latching lever 28 is also rotated in the same direction, the latching pin 29 of the latching lever 28 comes into contact with the latching protrusion 33, so that the closing prevention lever 30 resists the biasing force of the tension spring 32. It is rotated in the direction of the Q arrow. Since the locking pin 29 gets over the locking protrusion 33 before the tension spring 32 crosses the line X,
The closing prevention lever 30 is rotated in the opposite direction of the arrow Q by the biasing force of the tension spring 32, and the locking lever 2
8 is locked so that rotation in the opposite direction of the P arrow is impossible.

Next, move the lock plate 35 upwards, and
With the lock 40 in contact with the engagement protrusion 34 of the closing prevention lever 30, the lock 40 is held in the locked state by engaging the lock plate 35 and the latching holes 38, 39 of the fixed frame 2, as shown in FIG. . At this time, the display plate 41 of the lock plate 35 has the "unlocked" display at the bottom of the front face hidden behind the cover plate 2a, and the "earth lock" display at the top of the front face of the display board 41, so that it is difficult to carry out maintenance and inspection work in this state. In this case, as shown in FIG. 7, the closing prevention lever 30 cannot be freely released, and even if the operation shaft 21 is attempted to be rotated from the open state to the loading direction, the locking bottle 29 of the locking lever 28 will not be released. The operation shaft 21 is latched onto the latching protrusion 33 of the prevention lever 30.
is in a state in which it cannot be rotated, and even if the operation handle 22 is operated by mistake, it will not be possible to turn the operation handle 22, and it is safe.

Next, to return the switch to the normal state after maintenance and inspection, remove the lock 40 from the locking hole 39 of the fixed frame 2 and lock the lock plate 35 so that the upper end of the elongated hole 35a is locked with the screw 36. It moves down to the release position.
Then, the contact portion 37 of the lock plate 35 engages the engagement protrusion 3.
4 and enters the unlocked state. At this time, on the display plate 41 of the lock plate 35, the "earth lock" display on the upper front surface is hidden by the cover plate 2a, and the "unlock" display on the lower front surface appears.

Next, I will explain the opening/closing operation.
Operate the hook portion 30b to rotate the closing prevention lever 30 in the direction of the arrow Q, passing the line
(see figure). From this state, the operating shaft 21 is rotated in the opposite direction of the arrow P via the operating handle 22 to drive the opening/closing mechanism, thereby driving the movable contact blade 16 in the open state to close. As a result, as shown in FIG. 3, all phases of the grounding movable electrode 27 are disconnected from the grounding fixed electrode 26 at the same time, and then the movable contact blade 16 is inserted into the fixed insertion electrode 9.

On the other hand, when the locking lever 28 rotates in the direction of the opposite P arrow due to the rotation of the operation shaft 21 in the opposite direction of the P arrow, the locking bottle 29 is moved to the engaging protrusion 34 of the closing prevention lever 30.
By pressing against the upper surface of the lever 30, the injection prevention lever 30 is rotated in the direction of the arrow Q, crosses the line X, and is held at the position where the injection prevention lock is possible.
(see figure).

In addition, when carrying out a megger test of this switch, first, one end of the grounding wire L is removed from the mounting base 1 to release the connection. After this, if one end of the grounding wire L is connected to the mounting base 1 again and grounded, the initial state is restored.

After the fixed frames 2, 3, etc. on the side of the machine frame K are disconnected from the ground by the ground wire L in this manner, a megger test can be easily performed.

Note that this invention is not limited to the above-described embodiment, and for example, the lock mechanism A of the above-mentioned embodiment may be placed between any of the phases, and may be arbitrarily modified without departing from the spirit of this invention. It is possible.

Effects of the invention As detailed above, this invention automatically maintains the various circuits below the switch in a grounded state by opening the switch of the present invention, which is the main interrupting device, during maintenance and inspection. The possibility of malfunction (turning on) of the lock mechanism A is completely avoided, and maintenance and inspection can be performed safely and easily, and the time can be shortened, which is an excellent effect.

[Brief explanation of the drawing]

Fig. 1 is a front view of a switch embodying this idea in a closed state with the current limiting fuse omitted, Fig. 2 is a bottom view, and Fig. 3 is a closed state of the movable contact blade. 4 is a side view showing the movable contact blade in the open state, FIG. 5 is a side view of the lock mechanism in the closed state of the switch, and FIG. 6 is a side view of the lock mechanism in the unlocked state. , FIG. 7 is a side view of the lock mechanism similarly showing the open lock state, and FIG. 8 is a front view of the main part showing the function of the display plate of the lock plate. 1... Mounting base, 2, 3... Fixed frame,
4... Upper support insulator, 6... Lower support insulator, 9...
... Fixed sandwiched electrode, 11 ... Fuse support stand, 12
...Upper fuse clamping fitting, 13...Lower fuse clamping fitting, 16...Movable contact blade, 20...Pushing rod, 21...Operation shaft, 22...Operation handle,
23...Insulating plate, 24...Common support fitting, 26...
... Fixed electrode for grounding, 27 ... Movable electrode for grounding, 2
8...Latching lever, 29...Latching bottle, 30...
Closing prevention lever, 32... tension spring, 35...
Lock plate, A...Lock mechanism, K...Machine frame.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A pair of upper and lower support insulators is fixed to the mounting base that constitutes the machine frame, a fixed electrode is provided on the upper support insulator, and both ends of the current limiting fuse are provided on the lower support insulator. A fuse support stand equipped with upper and lower fuse clamping fittings is provided, and a movable contact blade that is electrically connected to the current limiting fuse and that is opened and closed via an opening/closing mechanism by rotation of the operating shaft is connected to the fixed electrode. In a pneumatic switch with a current limiting fuse that can be connected to and separated from the machine frame K below the lower support insulator 6 of each phase.
Grounding fixed electrode 2 arranged insulated from
6 is fixed, the grounding fixed electrodes 26 of the same phase are electrically connected to each other, and the movable contact blade 16 is electrically connected via a connecting member 24 connectable to the machine frame K. A grounding movable electrode 27 is extended at the base end and comes into contact with the grounding fixed electrode 26 after the movable contact blade 16 is opened when the opening operation is performed, and is further rotatable with respect to the machine frame K. a closing prevention lever 3 which is pivotally supported by the lever 3 and which restricts rotation of the operating shaft 21 in the closing direction in the locked position;
0, a tension spring 32 that is hung on the closing prevention lever 30 and biases and holds the closing prevention lever 30 in the lock position, and a tension spring 32 that is arranged so as to be able to approach and separate from the closing prevention lever 30 and that is attached to the closing prevention lever 30. A pneumatic switch with a current-limiting fuse, characterized in that a locking mechanism A is provided, comprising a locking plate 35 that holds the closing prevention lever 30 in a locked position in an engaged, non-released position. 2. The grounding fixed electrode 26 is fixed to a common support fitting 24 common to each phase, which is attached to the machine frame K via an insulating plate 23. Claim 1 of the Utility Model Registration Claim Pneumatic switch with current-limiting fuse.