JP3961753B2 - Interior parts support structure for switches - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an interior part support structure for a switch such as a zero-phase current transformer and a cut-off relay.
[0002]
[Prior art]
Conventionally, for example, an interior part for a switch such as a zero-phase current transformer is fitted into an inner end of a bushing that is penetrated and supported by both side walls of a main body case while being accommodated in a mounting cover. The mounting cover is inserted into a bolt erected on the inner surface of the main body case, and is fixed in the main body case by tightening a nut to the bolt.
[0003]
[Problems to be solved by the invention]
However, in the conventional interior part supporting structure for a switch, it is necessary to provide a bolt for securing the interior part on the inner surface of the main body case. For this reason, there has been a problem that the insulation distance between the tip of the bolt and the electrode portion at the tip of the bushing is shortened and the withstand voltage between the grounds is lowered.
[0004]
The present invention has been made to solve the above problems, and an object of the present invention is to provide an internal part support structure for a switch that can improve the withstand voltage between the ground.
[0005]
[Means for Solving the Problems]
According to the first aspect of the present invention, an interior part for a switch is inserted and inserted into an inner end of a bushing penetratingly supported so as to face each side wall of each side of the body case. An insulating biasing member that biases the interior part toward the inside of the main body case is provided therebetween, and a positioning member that restricts the movement of the interior part toward the inner side of the main body case is provided within the main body case, and the positioning member Covers the fixed electrode provided at the inner end of one bushing and the movable electrode provided rotatably at the inner end of the other bushing so as to be able to contact and separate from the fixed electrode. The gist of the invention is that it is an insulation barrier that insulates between different phases and between the ground .
[0006]
According to a second aspect of the present invention, in the first aspect of the invention, the insulating biasing member is interposed between a flange formed on the outer end side of the bushing and an outer surface of the main body case, and is airtight inside and outside the main body case. The gist of the present invention is that it is formed integrally with a seal member that holds
[0007]
( Function)
In the first aspect of the present invention, the interior part for the switch is urged inward of the main body case by the insulating urging member. The movement of the interior part to the inside of the main body case is restricted by the positioning member. That is, the interior part is held in a state of being inserted into the inner end of the bushing. In addition, the interior parts for the switch are positioned by installing an insulation barrier in the body case.
[0008]
In the invention described in claim 2, in addition to the action of the invention described in claim 1, the edge portion of the inner surface of the bushing penetrating portion of the main body case is covered with an insulating material. For this reason, the creeping distance between the electrode portion at the inner end of the bushing and the edge portion of the inner surface of the bushing penetrating portion increases, and the concentration of the electric field at the edge portion of the bushing penetrating portion is reduced.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which the present invention is embodied in an interior part support structure for a switch will be described with reference to FIGS.
(overall structure)
As shown in FIG. 1, the case of the switch 11 includes a closed box-like main body case 12 having an open bottom, and a bottomed box-like bottom case 13 having an open top. The opening is closed by the bottom case 13. That is, by tightening the fastening piece 14 provided at the opening side edge of the bottom case 13 to the connecting piece 15 provided at the opening side edge of the main body case 12 with the bolt 16 and the nut 17, Is detachably connected to the main body case 12. A packing 18 is interposed between the main body case 12 and the bottom case 13, whereby the airtightness of the switch 11 is maintained.
[0011]
A power-side bushing 21 and a load-side bushing 22 are supported through the opposite side walls of the main body case 12 so as to face each other for each of the three phases (only one phase is shown in FIG. 1). . A rod-like fixed electrode 23 is fixed to the inner end portion of the power supply side bushing 21. A support member 24 is fixed to the inner end portion of the load side bushing 22, and a base end portion of the movable electrode 26 is rotatably supported by the support member 24 via a shaft 25. The movable electrode 26 includes a pair of contact blades (only one contact blade is shown in FIG. 1) arranged in parallel.
[0012]
On the other hand, a rotating shaft 27 operatively connected to an operation handle (not shown) outside the body case 12 is provided at an upper portion in the body case 12 via an opening / closing mechanism (not shown) composed of a plurality of links and the like. A lever 28 is fixed to the rotation shaft 27 so as to be integrally rotatable. One end of a drive link 29 is rotatably connected to the tip of the lever 28, and the other end of the drive link 29 is rotatably connected to the vicinity of the center of the movable electrode 26. Therefore, when the operation handle is operated, the movable electrode 26 is moved to the closing position shown by a solid line in FIG. 1 and the shaft 25 through the opening / closing mechanism section, the rotating shaft 27, the lever 28 and the drive link 29 as shown in FIG. Move between the open positions indicated by the two-dot chain line.
(Interior parts support)
As shown in FIGS. 2 and 3, an interior component support tool (hereinafter referred to as “support tool”) 31 is attached to each bushing penetrating portion 12 a of the main body case 12. The support 31 is integrally formed of an insulating and elastic synthetic resin material such as EPDM, and includes a cylindrical support portion 31a, a seal portion 31b, and a biasing portion 31c as an insulating biasing member. Yes. The outer diameter of the support portion 31a is set to a size that can be fitted into the bushing penetrating portion 12a. Similarly, the inner diameter is set such that the inner end side can be fitted to the flanges 21a and 22a of the bushings 21 and 22. The seal part 31b is provided so as to form an annular shape on the outer periphery of one end part of the support part 31a. The urging portion 31c is projected so as to form a truncated cone shape on the inner end side of the seal portion 31b on the outer periphery of the support portion 31a. The seal portion 31b and the biasing portion 31c are separated by a distance corresponding to the thickness of the side wall of the main body case 12, and the mounting recess 32 is constituted by the outer periphery of the support portion 31a, the seal portion 31b, and the biasing portion 31c. Has been.
[0013]
As shown in FIG. 3, an opening edge of the bushing penetrating portion 12 a in the main body case 12 is interposed in the attachment recess 32. That is, the opening edge (inner surface edge) of the bushing penetrating portion 12a is covered with an insulating synthetic resin material such as EPDM. Each of the bushings 21 and 22 is inserted through a support portion 31a of a support tool 31 attached to the bushing penetrating portion 12a. As shown in FIG. 1, a plurality of bolts 33 are erected on the outer surface of the side wall of the main body case 12 in the vicinity of the bushing penetrating portion 12a. Each bolt 33 is inserted with a flange retainer 34 that covers the flanges 21a and 22a of the bushings 21 and 22, and the bushings 21 and 22 are fixed to the main body case 12 by tightening the nut 35 from the outside. Has been.
[0014]
As shown in FIGS. 2 and 3, the seal portion 31 b of the support tool 31 is sandwiched between the flanges 21 a and 22 a of the bushings 21 and 22 and the side wall outer surface of the main body case 12. Internal and external airtightness is maintained. A cased zero-phase current transformer 36 is fitted on the inner end side of the power supply side bushing 21, and a cutoff relay 37 is fitted on the inner end side of the load side bushing 22. That is, in the cased zero-phase current transformer 36 and the cut-off relay 37, the bushing insertion holes 36a and 37a corresponding to the three-phase power supply side and load side bushings 21 and 22, respectively (in FIG. 2 and FIG. Only minutes are shown). The bushing insertion holes 36a, 37a are inserted through the inner ends of the power supply side and load side bushings 21, 22 and the inner end side of the urging portion 31c of the support portion 31a. Incidentally, to case containing zero-phase current transformer 36 and the cut-off relay 37 and the like constitute the interior part of the opening and closing dexterity.
[0015]
As shown in FIG. 1, an insulating barrier 41 described later is disposed between the cased zero-phase current transformer 36 and the cutoff relay 37. The cased zero-phase current transformer 36 and the cut-off relay 37 are pressed toward the biasing portion 31c by a pair of side walls facing each other in the in-phase direction of the insulating barrier 41, and the elasticity of the biasing portion 31c. It is always urged inward of the main body case 12 by force. That is, the cased zero-phase current transformer 36 and the cut-off relay 37 are held at the inner ends of the bushings 21 and 22 at a predetermined holding pressure by installing the insulating barrier 41 in the main body case 12, respectively. . In other words, the cased zero-phase current transformer 36 and the cutoff relay 37 are each positioned by the insulating barrier 41.
(Insulation barrier)
As shown in FIGS. 1 and 4, an insulating barrier 41 as a positioning member is disposed in the main body case 12 independently for each phase (only one phase is shown in FIG. 1). The insulating barrier 41 is formed by injection molding a synthetic resin having insulating properties such as an unsaturated polyester resin. As shown in FIGS. 4 to 6, the insulating barrier 41 is formed in a bottomed box shape that covers both the electrodes 23 and 26 from below, and has a pair of side walls 41a, 41b is formed extending upward. In addition, recesses 42 and 43 are formed along the outer peripheral surfaces of the bushings 21 and 22, respectively, on the upper portions of the pair of side walls 41c and 41d that face each other in a direction orthogonal to the phase direction. The insulating barrier 41 is arranged so that the bushings 21 and 22 and the electrodes 23 and 26 for each phase are located between the side walls 41a and 41b. The lower surfaces of the bushings 21 and 22 are engaged with the recesses 42 and 43, respectively. Match.
[0016]
(Engagement means)
As shown in FIG. 5, in a pair of side walls 41a, 41b facing each other in the direction of different phases of the insulating barrier 41, three engaging recesses 44 are arranged and formed in an inverted triangle shape on one side wall 41a. Also, as shown in FIG. 6, three engaging convex portions 45 are arranged and formed in an inverted triangular shape on the other side wall 41b. As shown in FIG. 4, in the installation state of each insulation barrier 41 in the main body case 12, the engagement concave portions 44 and the engagement convex portions 45 of the side walls 41a and 41b adjacent to each other are engaged with each other. That is, as shown in FIG. 7, the engaging convex portion 45 is located in the engaging concave portion 44, thereby preventing movement of each insulating barrier 41 in the direction along the side walls 41 a and 41 b.
[0017]
(Connecting means)
As shown in FIGS. 4 and 8, a cylindrical fitting portion 46 projects from the outer surface of the bottom wall of each insulating barrier 41. As shown in FIGS. 1 and 4, the insulating barriers 41 are connected to each other by attaching connecting members 47 to the respective fitting portions 46. That is, the connecting member 47 is formed in an elongated shape with an insulating synthetic resin, and the connecting member 47 has three fitting holes 47a in the installed insulating barriers 41 in the installed state. It is arranged and formed so as to be the same interval as the arrangement interval in the phase direction. And each insulation part 41 is connected by each fitting part 46 being each fitted by each fitting hole 47a. The thickness of the connecting member 47 is made smaller than the protruding height of the fitting portion 46 from the outer surface of the bottom wall of the insulating barrier 41, and each fitting portion 46 protrudes from the lower surface of the attached connecting member 47.
[0018]
(Interference prevention member)
As shown in FIGS. 1 and 4, an interference preventing member 48 is attached to a protruding portion of each fitting portion 46 from the lower surface of the connecting member 47. That is, the interference preventing member 48 is formed in an L-shaped side section with a rubber material having insulating properties and elasticity, and is formed so as to have a concavo-convex relationship with the connecting member 47. In addition, the interference preventing member 48 is formed with three through holes 48a at the same intervals as the fitting holes 47a. Projecting portions from the lower surface of the connecting member 47 of the respective fitting portions 46 are fitted into the respective through holes 48a. In the mounted state of the interference preventing member 48, the tip end portion of each fitting portion 46 is located inside each through hole 48a. The bottom surface of the interference preventing member 48 is in contact with the inner surface of the bottom case 13, thereby preventing interference between each insulating barrier 41 and the inner surface of the bottom case 13.
[0019]
(View window)
As shown in FIGS. 1 and 8, a circular viewing window 49 is formed at the lower portion of the side wall of the insulating barrier 41 on the load side bushing 22 side. The inspection window 49 is formed in a position, size (diameter), and position so that the electrode structure and the like inside the insulation barrier 41 can be confirmed from the outside during the installation state of the insulation barrier 41 in the main body case 12 or during the installation. The shape etc. are set. The viewing window 49 also serves as a mounting portion for a cushion 52 described later.
[0020]
(Blind member)
As shown in FIGS. 1 and 8, a blind member 51 is attached to the viewing window 49, thereby closing the viewing window 49. The blind member 51 includes a cushion 52 as a buffer member and a puffer member, and a support cylinder 53 as a transmission member.
[0021]
(cushion)
As shown in FIG. 9, the cushion 52 is formed in a cylindrical shape with an outer end portion made of a synthetic resin material having insulation and elasticity such as EPR. An annular attachment groove 54 is formed on the outer periphery of the outer end portion of the cushion 52, and an opening edge of the observation window 49 in the insulating barrier 41 is interposed in the attachment groove 54. An air blowing hole 55 is formed at the center of the wall surface of the inner end of the cushion 52. On the inner periphery of the outer end portion of the cushion 52, a tapered surface 56 that expands outward and a large diameter portion 57 that is larger than the inner diameter of the inner end portion are formed continuously.
[0022]
As shown in FIG. 10, when the movable electrode 26 tries to overrun in the opening direction due to its inertial force when opening the circuit, that is, when it tries to rotate beyond the predetermined open position shown by the two-dot chain line in FIG. The length, diameter, and attachment position of the cushion 52, that is, the position where the viewing window 49 is formed are set so that the back surface of the movable electrode 26 collides with the inner end of the cushion 52. When the back surface of the movable electrode 26 collides with the inner end portion of the cushion 52, the cushion 52 is crushed.
[0023]
(Support tube)
As shown in FIG. 9, the support cylinder 53 is formed in a cylindrical shape having an outer end portion made of an insulating synthetic resin material such as polyethylene. A frustoconical sealing portion 58 having a diameter increasing toward the outer end portion is formed at the inner end portion of the support cylinder 53, and the maximum diameter of the sealing portion 58 is larger than that of the large diameter portion 57 of the cushion 52. The diameter is slightly larger. A flange portion 59 is formed in the vicinity of the center of the outer periphery of the support cylinder 53, and a flat surface is formed on the cushion 52 side of the flange portion 59.
[0024]
As shown in FIG. 10, the inner end side of the flange portion 59 of the support cylinder 53 is fitted from the outside into the hollow portion of the cushion 52 attached to the viewing window 49. The movement of the support cylinder 53 toward the inner side of the insulating barrier 41 is restricted by the flat surface of the flange portion 59 of the support cylinder 53 engaging the opening end of the cushion 52. An elastic force inward of the cushion 52 acts on the outer periphery of the sealing portion 58 of the support cylinder 53, and the sealing portion 58 and the tapered surface 56 of the cushion 52 are in close contact with each other. That is, the opening at the outer end of the cushion 52 is sealed by the support cylinder 53. Therefore, when the back surface of the movable electrode 26 collides with the inner end portion of the cushion 52 and the cushion 52 is crushed when the circuit is opened, the air inside is compressed and pushed out through the blowout hole 55. Further, the back surface of the support cylinder 53, that is, the opening end portion is in contact with the inner surface of the bottom case 13, and an impact when the movable electrode 26 collides with the inner end portion of the cushion 52 passes through the support cylinder 53 and the bottom case 13. To the main body case 12.
[0025]
(Cable binding member)
As shown in FIG. 8, a plurality of binding members 61 protrude from the peripheral edge of the bottom wall of the insulating barrier 41. As shown in FIG. 11A, the binding member 61 is formed with an insertion hole 61a through which the binding band 62 can be inserted. As shown in FIG. 11 (b), various cables 63 such as control lines are gathered along the bottom side of each insulating barrier 41 and wound by a binding band 62 inserted through the insertion hole 61a. It is fixed with respect to the insulating barrier 41.
(Effect of embodiment)
Next, the operation and effect of the interior part support structure for a switch configured as described above will be described.
[0026]
(1) A biasing portion 31c of the support 31 is interposed between the case-containing zero-phase current transformer 36 and the cut-off relay 37 and the main body case 12, which are fitted into the inner ends of the bushings 21 and 22, respectively. It was. For this reason, the cased zero-phase current transformer 36 and the cutoff relay 37 are urged inward of the main body case 12 by the elastic force of the urging portion 31c. Movement of the cased zero-phase current transformer 36 and the cut-off relay 37 inward of the main body case 12 is restricted by an insulating barrier 41 installed in the main body case 12. That is, by installing the insulating barrier 41 in the main body case 12, the cased zero-phase current transformer 36 and the cut-off relay 37 are held in the main body case 12 in a state of being fitted into the inner ends of the bushings 21 and 22. Is done. For this reason, unlike the case where the cased zero-phase current transformer 36 and the cut-off relay 37 are fixed to the inner surface of the main body case 12 by bolts, the bolts and the electrode portions at the tips of the bushings 21 and 22 (fixed electrode 23 and movable electrode 26). The problem of the short insulation distance between the two is solved. Therefore, the withstand voltage between the grounds can be improved.
[0027]
(2) The insulating barrier 41 also serves as a positioning member that restricts the movement of the case-containing zero-phase current transformer 36 and the cut-off relay 37 into the main body case 12. For this reason, the cased zero-phase current transformer 36 and the cut-off relay 37 are held in place by installing the insulating barrier 41 in the main body case 12. Therefore, it is not necessary to separately provide a member for positioning the cased zero-phase current transformer 36 and the cutoff relay 37.
[0028]
(3) The cased zero-phase current transformer 36 and the cut-off relay 37 are urged inward of the main body case 12 by the elastic force of the urging portion 31c, and the insulating barrier 41 is used to urge the outer case 12 Part 31c side). That is, the cased zero-phase current transformer 36 and the cut-off relay 37 are held in a state of being inserted into the inner ends of the bushings 21 and 22. For this reason, the bolt etc. for fixing the cased zero phase current transformer 36 and the cut-off relay 37 in the main body case 12 become unnecessary. Therefore, the number of parts can be reduced. Moreover, the attachment work with respect to the main body case 12 of the cased zero phase current transformer 36 and the cut-off relay 37 can be simplified.
[0029]
(4) The urging portion 31c and the seal portion 31b are integrally formed. That is, the edge part of the inner surface of the bushing penetrating part 12a of the main body case 12 is covered with an insulating material such as EPDM forming the urging part 31c and the seal part 31b. For this reason, the creeping distance between the electrode portions at the inner ends of the bushings 21 and 22 and the edge portion of the inner surface of the bushing penetrating portion 12a increases, and the concentration of the electric field at the edge portion of the bushing penetrating portion 12a is alleviated. Therefore, a flash between the grounds can be prevented more reliably.
[0034]
【The invention's effect】
According to the present invention, since the positioning member that restricts the movement of the interior parts to the inside of the main body case is also used as the insulating barrier, it is not necessary to stand the bolt on the inner surface of the main body case of the switch, and the bolt and the bushing tip Since the problem that the insulation distance between the electrode portions is short is solved, the withstand voltage between the grounds can be improved.
[Brief description of the drawings]
FIG. 1 is a front sectional view of a switch.
FIG. 2 is an exploded front view of a bushing attachment portion.
FIG. 3 is a front cross-sectional view of a main part of a bushing attachment portion.
FIG. 4 is a side view showing an engagement state of insulating barriers for three phases.
FIG. 5 is a perspective view of an insulation barrier.
FIG. 6 is a perspective view of an insulation barrier.
FIG. 7 is an enlarged cross-sectional view of a main part showing an engagement state between an engagement recess and an engagement protrusion.
FIG. 8 is a perspective view of an insulation barrier.
FIG. 9 is an exploded front sectional view showing attachment of a cushion and a support cylinder.
FIG. 10 is a front sectional view showing attachment of a cushion and a support cylinder.
11A is a schematic perspective view showing attachment of a binding band to a binding member, and FIG. 11B is a perspective view showing a state in which various cables such as control lines are wound around.
[Explanation of symbols]
11 ... Switch, 12 ... Body case, 13 ... Bottom case,
21 ... Power side bushing, 22 ... Load side bushing, 23 ... Fixed electrode,
26 ... movable electrode, 28 ... lever,
31 ... Interior part support tool, 31a ... Support part, 31b ... Seal part,
31c ... biasing part (insulating biasing member),
36. Zero-phase current transformer with a case constituting an interior part for a switch,
37. Cut-off relay constituting the interior parts for the switch,
41 ... insulating barrier (positioning member), 21a, 22a ... flange.

Claims (2)

The internal parts for the switch are inserted into the inner ends of the bushings that are penetrated and supported on both side walls of the main body case so as to face each side, and the internal parts are inserted between the inner parts and the main body case. An insulative urging member that urges inward is provided , and a positioning member that restricts the movement of the interior part into the main body case is provided in the main body case .
The positioning member includes a fixed electrode provided at an inner end of one bushing, and a movable electrode provided rotatably at an inner end of the other bushing so as to correspond to the fixed electrode. An interior part support structure for a switch, which is an insulating barrier that insulates between different phases and between the ground by covering . 2. The insulating urging member is formed integrally with a seal member that is interposed between a flange formed on an outer end side of the bushing and an outer surface of the main body case to maintain airtightness inside and outside the main body case. Support structure for interior parts for switchgear .

Images