JP4578019B2 - Air conditioner switch with protective frame - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a switch for aerial work with a protective frame. More specifically, the switch body is made of an electrically insulating resin, and the protective frame is attached to the switch body so as to surround the switch. The present invention relates to a switch for aerial work with a protective frame.
[0002]
[Prior art]
In a high-voltage distribution line, when a work such as a replacement of a distribution line and a changeover of a switch and a transformer are performed, the work is generally performed without a power failure.
[0003]
In this uninterruptible construction, without suspending power transmission during construction work to customers in the construction section, a bypass circuit will be formed using cables, construction switches, etc., and power transmission will be continued by this bypass circuit. It is a thing.
By the way, the construction switch used to form the bypass circuit is usually installed at the sales office of the electric power company or the sales office of the construction company entrusted by the electric power company. It is loaded onto a construction vehicle, transported to the site, and temporarily installed on a utility pole at the construction site.
[0004]
That is, since the construction switch used temporarily is transported to the construction site each time, the frequency of transportation is high, and the number of times of attachment to or removal from the utility pole is high.
[0005]
[Problems to be solved by the invention]
Therefore, as a construction switch, it is necessary to reduce the weight and size in consideration of the above transportation, attachment and removal, but the conventional construction switch is a general on-pillar switch that is permanently installed in the distribution line. As is the case with conventional steel plates and stainless steel plates, etc., and the switch body (case body) is manufactured by using cans, etc., the weight has not yet been reduced. is there.
[0006]
In addition, as described above, when the main body (case) is made of a metal such as a steel plate, a sufficient insulation (space) distance between a charged part such as an electrode and the main body (case) is ensured to achieve a predetermined withstand voltage performance. There is a limit to the miniaturization of the main body because it must be obtained.
[0007]
[Means for Solving the Problems]
The present invention is for solving the above technical problem, and the first invention is formed of an insulating synthetic resin and has a main body that exceeds a pressure defined in an airtight test at the time of an internal short circuit. When the internal pressure rises, a switch body having a pressure release device that releases the pressure to the outside of the main body, and a switch body that is attached to the switch body so as to surround the switch body are connected to the utility pole. It is a switch for aerial type construction with a protective frame comprising a metal protective frame having a column part capable of direct mounting.
[0008]
The second invention is characterized in that, in the first invention, the pressure defined in the airtight test is 19.6 KPa (0.2 kgf / cm ² ).
[0009]
According to a third invention, in the first or second invention, the pressure relief device is formed by providing a pressure relief lid on an upper side of a switch body, and the protection device is located above the pressure relief lid. The frame is provided with a protective cover for restricting the scattering of the pressure relief lid during pressure relief.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to FIGS.
First, the switch body 2 in the aerial work switch 1 will be described.
The container-shaped switch main body 2 includes a main body 3 and a lid body 4. Among these, the main body 3 includes, for example, a low-viscosity cyclic aliphatic epoxy resin main agent and a carboxylic acid anhydride-based curing agent that is solid at room temperature. Is formed by a pressure gelation method which is one of casting methods. In other words, in the above, the main body 3 is molded after a bushing part such as a center conductor, which will be described later, and various screws and nuts for mounting are not moved at a predetermined position of a casting mold having a predetermined shape. Inject the liquid epoxy resin in the casting tank under pressure into the mold (inside) heated to a temperature higher than the resin temperature, and continue to feed until the resin is solidified, wait for curing, and mold Therefore, the molding material and the molding molded by the molding method are less likely to generate internal distortion and void than direct pressure molding even at a relatively low pressure, and further, UV resistance, mechanical properties, tracking resistance, Those having excellent characteristics such as arc resistance and environmental resistance (not producing environmental hormones) can be obtained.
[0011]
The molding material used for molding the main body 3 uses an electrically insulating synthetic resin. In addition to the above epoxy resin, a liquid / modified cycloaliphatic epoxy resin is the main ingredient, and a liquid modified alicyclic anhydrous curing agent. In addition to the above pressure gelation method, a general vacuum casting method can also be used as the molding method.
[0012]
By these forming means, central conductors 5 and 6 made of copper or the like are inserted into predetermined positions at the centers of the bushings 3a and 3b formed integrally when the main body 3 is formed. The distance between the central conductors of the inserted bushings 3a, 3b, that is, the pitch between the phases, is accurately determined by the above molding, and various mounting nuts arranged in the respective parts are also predetermined. It is inserted in a state of being accurately positioned at the position.
[0013]
Reference numerals 3a and 3b denote a load side bushing portion and a power source side bushing portion which are simultaneously molded when the main body 3 is molded, and each bushing portion 3a and 3b has a copper center provided with female contacts 5a and 6a. The conductors 5 and 6 are inserted, and further, a contact assisting piece 7 having a slit-like shape with appropriate elasticity is inserted along the inner peripheral surface of the contacts 5a and 6a. Good contact is maintained between the male contacts 8a and 9a of the cable attachments 8 and 9, which will be described later.
[0014]
Reference numeral 5 denotes a center conductor of the load side bushing 3a made of the stud bolt inserted at the time of molding as described above, and one end 5b located inside the case is connected to the fixed electrode 11 through the conductive member 10, and the load side bushing The central conductor 6 of the power-source-side bushing 3b inserted in the same position opposite to the position 3a is electrically and mechanically attached to one end 12b of the blade-shaped movable electrode 12 at one end 6b in the case. Then, the movable electrode 12 that is pivotally connected to the load is sandwiched and brought into contact with the clip-type fixed electrode 11 on the load side to form an energization path.
[0015]
The movable electrode 12 is connected to an opening / closing operation handle 14 via a link mechanism 13 and an operation mechanism 59 (see FIG. 2). When the operation handle 14 is turned in the closed state of FIG. The operation lever 16 that rotates in the clockwise direction and moves integrally with the coaxial 15 moves in the clockwise direction, so that the intermediate lever 18 that is attached to the shaft 17 on the lever 16 is pushed down, and the movable electrode that is attached to the intermediate lever 18 on the shaft 19. 12 rotates clockwise about the shaft 30, the contact portion 12 a at the tip of the movable electrode 12 that is sandwiched and in contact with the fixed electrode 10 is detached from the fixed electrode 10, and further between the electrodes 12, 10. The arc generated at the time of separation passes through the slit of the arc-extinguishing chamber 20 together with the movable electrode 12, and the arc is extinguished by the arc-extinguishing gas generated from the arc-extinguishing chamber forming member when passing through the arc. 0 movable electrode 12 which is separated from the large spaced insulation is ensured, so as to path open is complete. In FIG. 2, 58 indicates an insulating separator interposed between the phases.
[0016]
The above description is for the case where the electric circuit is opened by turning off the switch in the on state (closed circuit). On the contrary, the operation of the closing operation for turning on the switch in the cut state (open circuit) is on. In this case, the operation is the reverse of the above.
[0017]
Reference numeral 4 denotes a lid that constitutes the switch body 2 together with the main body 3, which is formed by the same material and the same molding method as the main body 3, and the lid 4 covers the lower opening 3 c of the main body 3. In this way, the mounting flange portion 4a is overlapped on the mounting flange portion 3e of the main body 3 and screwed to the main body 3 with bolts 21 and nuts 22. When the lid body 4 and the main body 3 are screwed (attached), airtightness is achieved. A holding O-ring 57 is interposed between the flanges 3e and 4a. Reference numerals 3d and 4c denote reinforcing ribs.
[0018]
Reference numerals 24 and 25 are mounting reinforcing plates made of a thin plate such as a stainless steel plate, an aluminum steel plate, and a normal steel plate, which are fixed to the front surface 2a and the back surface 2b of the switch body so as to cover the entire surface of these surfaces. 24, 25 are three-phase (three) insertion holes 24au, 24av, 24aw, 25au, 25av, 25aw arranged in the upper part thereof, U-phase bushings 3au, 3bu, V-phase bushings 3av, 3bv, The W-phase bushings 3aw and 3bw are inserted into the bushings, and screws 26 are attached from the outside to the mounting nuts (not shown) on the inserted main body side to open and close the mounting reinforcing plates 24 and 25. The switch body 2, which is integrally fastened to the main body 2, and the reinforcing plates 24, 25 are fastened, is further attached to mounting holes 24 c, 25 above the reinforcing plates 24, 25 with respect to the protective frame 40 described later. Are connected to the connecting member 56 fixed to the protective frame 40 by screws 48, and the lower mounting holes 24d and 25d are connected to the receiving plate 28 fixed to the protective frame 40 by screws 29 to connect the protective frame 40 and the switch. The main body 2 is assembled integrally.
[0019]
Reference numerals 24fu, 24fv, 24fw, 25fu, 25fv, 25fw are mounting rings that are integrally fixed to the reinforcing plates 24, 25 by welding so as to surround the respective insertion holes 24au, 24av, 24aw, 25au, 25av, 25aw. For attaching the attachments 8 and 9 detachably, the L attachments 8 and 9 side with respect to the screw portions 24e (24eu, 24ev, 24ew) and 25e (25eu, 25ev, 25ew) on the peripheral surface of the attachment ring The threaded portions 8c and 9c of the cap nut-shaped mounting caps 8d and 9d are screwed to attach the L-shaped attachments 8 and 9 made of aluminum alloy to the bushing portions 3a and 3b. .
[0020]
In order to form a bypass circuit for the L-shaped attachments 8 and 9 fixed and attached as described above, the linear terminal type cable inserted from the lower insertion ends 8b and 9b side is attached to the attachments 8 and 9 respectively. An electrical circuit is formed by contacting the contact members 5a and 6a of the central conductor of the bushing through the intermediate contact members 8a and 9a.
[0021]
The attachment reinforcing plates 24 and 25 and the attachments 8 and 9 and the cables are attached by attaching the attachments 8 and 9 to the attachment rings 24fu, 24fv, 24fw, 25fu, 25fv, and 25fw and attaching the cables to the attachments 8 and 9. The sheath is electrically connected and grounded.
[0022]
32 is a pressure relief device located on the upper surface side of the main body 3. The pressure relief port 3 g formed at the time of molding the main body 3 and the epoxy resin similar to that of the main body 3 or the lid body 4. Alternatively, a stopper-shaped pressure relief lid 33 manufactured by press-molding an aluminum alloy or a steel plate, an airtight holding O-ring 23, and a thin plate-like fastening piece 34 that presses (locks) to the upper surface side of the pressure relief lid 33. And a screw 35 for fixing the fixing piece 34 to a fixing portion 3h fixed to the main body 3, and a mounting nut 36 inserted into the main body 3.
[0023]
The pressure release device 32 has a pressure defined by JIS-C-0920 “General Rules for Waterproof Tests of Electric Machinery and Wiring Materials”, 19.6 KPa (0.2 kgf / cm ²⁾ relating to an airtight switch of an air switch. ), And when the internal pressure exceeds 19.6 KPa (0.2 kgf / cm ² ) due to the occurrence of an internal short circuit, the pressure relief lid 33 is quickly removed by the pressure. It is adjusted and set so as to release the increased internal pressure in the case to the outside of the case and suppress an excessive (abrupt) pressure increase. Specifically, for example, a fixing (regulatory) force of the pressure release lid 33 The fastening force is the short-circuit capacity of the applicable high-voltage distribution line, the internal volume of the switch body, the diameter of the pressure release port, the type of the O-ring, the wall thickness of the switch body (mechanical strength), etc. It will be set from. This prompt pressure relief operation protects the switch body from explosions during internal short circuits.
[0024]
Next, the metal protective frame 40 will be described mainly with reference to FIGS.
The protective frame 40 is assembled in a square frame shape by using a plate material such as aluminum, stainless steel, steel, or a bar material or a pipe material as appropriate, and the protective frame 40 has a U-shaped pipe member. Two guard parts 41, 41 formed by bending, a plate-like side part 44 screwed 43 on the opening end side of the guard parts 41, 41, and a bridge between the guard parts 41, 41 Upper-side positioning connecting members 56, 56 fixedly connected at two positions at an appropriate interval, and a lower-side receiving member fixedly connected at two positions at appropriate intervals in a bridging manner between the guard portions 41, 41. Connecting plates 42 and 42 made of the same pipe material as the guard portion 41 that connects the upper and lower sides of the guard portions 41 and 41 in a bridging manner, and a latch 45 attached to the side surface portion 44. It is composed of a columnar part 47 composed of a receiving piece 46.
The protection frame 40 is attached to the switch body 2 by removing the plate-like side surface 44 of the protection frame 40 shown in FIGS. 7 to 11, and in this state, the switch body 2 in the state shown in FIGS. Cover the frame 40 so that the operation handle 14 side is in the back, and reattach the side surface portion 44 once removed, and then reattach the upper side of the mounting reinforcing plates 24 and 25 on the switch body 2 side. The mounting holes 24 c and 25 c are connected to a connecting member 56 fixed to the upper side of the guard portion 41 of the protective frame 40 by screws 48, and the lower mounting holes 24 d and 25 d of the reinforcing plates 24 and 25 are connected to the protective frame 40. It connects with the receiving plates 28 and 28 adhering to the lower part side of the guard part 41 with the screw | thread 29. FIG.
[0025]
At the time of the connection, a hook-shaped protective cover 49 connected to the lower surface side of the connection member 56 by the screw 27 is located above the pressure-release cover 33 and is spaced apart, and the switch body The lid body 4 is mounted on the receiving plate 28 so that the weight of the switch body 2 is supported thereby. The switch body 2 is surrounded by a protective frame 40 by the attachment. And is in a guarded state.
[0026]
Next, the construction switch 1 having the above-described configuration will be described in terms of transportation and mounting to the power pole, as well as its pressure release operation.
The construction switch 1 stored in the sales office is loaded onto the construction vehicle and transported to the construction site. Of course, when the work is completed, the switch is removed from the utility pole, transported, and taken home.
[0027]
As shown in FIG. 17, the switch transported to the construction site is attached to the utility pole 50. First, as a preparation, prior to mounting the switch, a mounting device 54 having a hooking portion 51, a receiving portion 52, and a locking pin 53 is attached to a predetermined position of the utility pole. The hook 55 provided in the switch is lifted by a crane via a rope (not shown in particular) with respect to the attached mounting device 54, and the latch 45 and the receiving piece 46 attached to the side surface 44 on the protective frame 40 side are The pin 53 is inserted and attached to the hook portion 51 and the receiving portion 52 on the attachment device 54 side attached to the utility pole 50.
[0028]
After installation, a cable is connected to the bushing of each phase to form a bypass circuit for temporary power transmission. In addition, the said operation | work demonstrates centering on the column work of a switch, and does not specifically explain other operations, such as an attached confirmation test.
In the above, the switch body is made of a synthetic resin, so that the weight and size can be reduced, and the workability can be improved during transportation and mounting.
[0029]
In addition, the protective frame can protect the resin switch body from collision with other equipment during transportation and loading.
Also, assume that an internal short circuit accident occurred in the switch for some reason when the bypass circuit was formed as described above and was transmitted to the construction section. An arc is generated by a short circuit, and the internal pressure rises due to the arc, and when it exceeds the pressure of the airtight test, the pressure relief lid 33 is pushed up from the inside by the pressure, and the pressure relief lid 33 that presses from the outside is stopped. The wearing piece 34 is bent thereby, and the lid 33 is detached from the pressure release port 3g. If the internal pressure increase value is small, a gap is formed between the pressure relief port 33 and the pressure relief lid 33.
[0030]
The internal pressure that has increased due to the detachment is quickly released from the pressure release port 3g to suppress the increase in internal pressure, and the switch body is protected from destruction. The pressure relief lid 33 is separated from the pressure relief port 3g, and is then stopped by colliding with the protective cover 49, so that scattering and dropping are restricted. Even if it is a switch body made of synthetic resin, the pressure relief device Therefore, even if an accident such as an internal short circuit occurs and there is a sudden increase in internal pressure, a reliable pressure release operation can be expected and it is safe.
[0031]
【The invention's effect】
The present invention has the following effects by the above configuration.
Since the switch body is made of synthetic resin, when the switch body is molded by molding means such as casting, the center conductor of the bushing and the mounting nut parts can be molded at the same time. Dimensional accuracy such as positioning of nuts and the like is improved, and assembly work is facilitated.
[0032]
Since the switch main body is made of an insulating member, for example, in the main body (case), the insulation distance between the charging part and the ground can be made smaller than in the case of a conventional metal case, and the size of the switch main body can be reduced.
[0033]
Since the switch body is made of an insulating synthetic resin, the weight can be reduced. In addition, despite the fact that the switch body is made of synthetic resin as described above, a protective frame is attached around it to protect the switch body from collisions with other equipment, so the safety of the switch body is high. Become.
[0034]
The switch body is equipped with a pressure relief device that quickly releases the internal pressure that was raised in the initial stage of the internal pressure rise to the outside of the body in the event of an internal short circuit, and prevents explosion of the switch body. Even so, there is no explosion. At the same time, the mechanical strength of the switch body, that is, the thickness of the switch body made of synthetic resin at the time of molding can be made as thin as possible, and the weight can be reduced.
[0035]
Since the switch transported to the site can be directly mounted on the utility pole without removing the protective frame at the site, it is easy to work with.
[0036]
Since the protective cover is provided above the pressure relief lid of the pressure relief device, it is possible to prevent the pressure relief lid from being scattered or dropped during pressure relief. It is also possible to prevent the collision of equipment etc. against the direct pressure release lid.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an airborne construction switch with a protective frame according to an embodiment of the present invention.
FIG. 2 is a bottom view of the switch body before screwing the cover on the switch shown in FIG.
3 is a front view of the switch body of FIG. 1. FIG.
FIG. 4 is also a rear view.
FIG. 5 is a plan view of the same.
FIG. 6 is a right side view of the same.
7 is a front view of the protective frame shown in FIG. 1. FIG.
FIG. 8 is a right side view of the same.
FIG. 9 is a left side view of the same.
FIG. 10 is a plan view of the same.
FIG. 11 is a bottom view of the same.
12 is a front view of the mid-sized construction switch with protective frame in FIG. 1. FIG.
FIG. 13 is a left side view of the same.
FIG. 14 is a right side view of the same.
FIG. 15 is a bottom view of the same.
16 shows the protective cover shown in FIG. 1, wherein (a) is a front view, (b) is a side view, and (c) is a plan view.
FIG. 17 is a view showing a column (attachment) state of the mid-sized construction switch with protective frame shown in FIG. 1;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Switch for aerial construction 2 Switch body 3 Body 4 Cover body 32 Pressure release device 33 Pressure release cover 40 Protection frame 47 Pillar part 49 Protection cover 50 Telephone pole

Claims (3)

When the pressure inside the main body rises to a state where the pressure exceeds the pressure specified in the airtight test at the time of an internal short circuit, it is made of an insulating synthetic resin. A protective frame comprising a switch body comprising a metal protective frame having a column part attached to the switch body so as to surround the switch body and capable of being directly mounted on a power pole. Air conditioner construction switch. 2. The switch for an air-type construction with a protective frame according to claim 1, wherein the pressure defined in the airtight test is 19.6 KPa (0.2 kgf / cm ² ). The pressure relief device is formed by providing a pressure relief lid on the upper side of the switch body, and the protection frame is located above the pressure relief lid and restricts scattering of the pressure relief lid during pressure relief. The switch for aerial work with a protective frame according to claim 1 or 2, further comprising a cover.

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