JPH019063Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention relates to a rotary switch with a built-in lightning arrester element.

Conventional technology In the past, in order to protect the switch from lightning damage, a lightning arrester element was installed separately near the switch installation location.
It has been proposed that the switch be installed directly inside the switch case.

However, in the former case, when installing a lightning arrester at a switch facility, the lead wires on the track side and the wiring on the ground side are complicated, and accidents may occur due to moisture absorption, breakage of lead wires, staining, and damage caused by blows during construction. There is a problem that occurs. In the latter case, there is a problem that if the switch is simply attached directly to the switch case, the switch case becomes larger.

Purpose of the invention The purpose of this invention is to solve the above-mentioned problems and eliminate the need to increase the size of the switch case itself.
An object of the present invention is to provide a rotary switch with a built-in lightning arrester element that is easy to manufacture.

Structure of the invention In the rotary switch of this invention, a movable contact blade is insert-molded into the movable insulator, which is integrally molded with synthetic resin, so that it passes through the axis of rotation almost orthogonally and is immovable relative to the movable insulator. On the other hand, in a rotary switch equipped with a rotating shaft that rotates a movable insulator to open and close, a charging side electrode of the movable insulator is electrically connected to the movable contact blade, and a grounding side electrode is electrically connected to the rotating shaft. The lightning arrester element connected to the ground is buried.

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

Reference numeral 1 in the drawings indicates a closed case, and in FIG. 1, fixed electrodes (not shown) on the power supply side and load side are arranged facing each other between the front and rear walls (not shown) for each phase.

Reference numerals 2 and 3 refer to bearing fittings fixed to the left and right inner wall surfaces of the case 1, and between the coaxial bearing fittings 2 and 3 there are rotary movable electrodes (later attached) that correspond to the three-phase fixed electrodes so as to be able to come into contact with and separate from them. (described in detail) are supported so that the three phases can rotate together.

Therefore, the rotary support mechanism of the movable electrode will be explained with reference to FIG. The support shafts 6 and 7 are mounting plates made of a conductive material and fixed at their centers to the other ends of the support shafts 4 and 5.

8 and 9 are the support shafts 5 for the one mounting plate 7;
It is a rotating shaft made of a pair of conductive materials that protrudes in the opposite direction to the supporting shaft 5 so as to be parallel to the rotational axis of the supporting shaft 5, and the distal ends of both the rotating shafts 8 and 9 have male threaded portions 8a,
9a is formed. A pair of holes 10 are provided in the other mounting plate 6 so that the rotating shafts 8 and 9 can be loosely inserted therethrough, and the male threaded portions 8a and 9a
By screwing nuts 11 into both mounting plates 6,
The movable electrodes for the three phases are tightened and fixed between the 7.

Reference numeral 12 is a driven lever fixed on the support shaft 4, and is connected to a manual/automatic opening/closing mechanism (not shown) of the switch.

Next, one phase of the movable electrode supported by the rotating shafts 8 and 9 will be explained with reference to FIGS. 7 and 8.
is an integrally molded movable insulator in which epoxy resin is injected into the mold (not shown) with the central part of the movable contact blade 14 inserted and fixed at a predetermined interval into a mold (not shown); As shown in FIG. 8, a pair of insertion holes 15 are provided through the rotary axis O at regular intervals parallel to the rotary axis O and symmetrically about the movable contact blade 14. The rotation shafts 8 and 9 are inserted into the insertion holes 15. Insulating folds 13a are integrally formed at both ends of the movable insulator 13 to improve voltage resistance characteristics between different phases.

The movable contact blade 14 is formed of a conductive material into a substantially S-shape as a whole, and has eighth blades on both edges of the central part.
As shown in the figure, an arc-shaped recess 14a is formed,
An arc-proof metal 14b is attached to the tip portion which is inserted into contact with the main fixed electrode (not shown).

Reference numeral 16 shown in FIG. 4 is a lightning arrester element buried during the molding of the movable insulator 13, and the movable contact blade 1
It is glued to the side of the central part of 4. The lightning arrester element 16 is composed of a non-linear resistance element 17 which is mainly made of zinc oxide (ZnO) with the addition of small amounts of several kinds of metal oxides and has excellent non-follow current characteristics. The charging side and grounding side electrode plates 18 and 19 made of silver or the like are baked and fixed, and the entire nonlinear resistance element 17 is molded 20 with silicone rubber or the like.

22 is the ground side electrode plate 1 of the lightning arrester element 16 at one end.
9, the other end of which is brazed to a connecting ring 23 made of a conductive material whose inner peripheral surface is exposed to one insertion hole 15 of the movable insulator 13 via a connecting fitting 22b. . In addition, connection ring 2
3 is disposed corresponding to the insertion hole 15 while being connected to the lead wire 22 during molding of the movable insulator 13.

As shown in FIGS. 3 and 5, 24 is a small diameter portion that is reduced in diameter at a position corresponding to the connection ring 23 on one rotating shaft 9, and 25 is the same small diameter portion 24 as shown in FIGS. 5 and 6. It is a substantially hexagonal grounding fitting that is driven into and fixed to the connecting ring 23, and is electrically connected to the inner circumferential surface of the connecting ring 23 at its corner.

Reference numerals 26 shown in FIGS. 8 and 9 are engagement protrusions for transmitting rotational torque that are formed integrally with two end faces of the movable insulator 13 when the movable insulator 13 is molded. The two engaging protrusions 26 are located at both ends of one diagonal line of a square centered on the coaxial line when viewed from the direction of the rotational axis of the movable insulator 13, and the two engaging protrusions 26 on the other end face side are They are located at both ends of another diagonal of the square.

Reference numeral 27 denotes a rotational torque transmission plate inserted through the rotating shafts 8 and 9 so as to be located between the movable insulators 13 of each phase, and is formed of a metal material into an oval shape, and is fixed at a constant distance from the center of rotation. Locking holes 29 are transparently provided at four locations spaced apart at equal angles, and engaging protrusions 26 of adjacent movable insulators 13 are respectively engaged in a pair of diagonally located locking holes 29.

Reference numeral 28 denotes a rotating torque transmission plate made of metal and inserted through the rotating shafts 8 and 9 so as to be located between the movable insulator 13 located at both ends and the mounting plates 6 and 7, respectively. Formed into an oval shape,
Further, similar to the locking hole 29, a locking hole 30 is transparently provided, and the engaging protrusion 26 of the movable insulator 13 is fitted into a pair of diagonally located locking holes 30.

Now, in the switch configured as described above, as shown in FIG. 1, when the movable contact blade 14 is rotated in the circuit closing direction by an external operation, the movable contact blade 14 comes into contact with a fixed electrode (not shown) and becomes energized. .

In this state, even if a lightning surge enters the switch, it will be discharged to the ground by the lightning arrester element 16 via the connection ring 23, ground fitting 25, rotating shaft 9, bearing fittings 2 and 3, and switch case 1, so that the switch can be closed or closed. It not only protects the switch itself from damage, but also protects the power distribution equipment connected to the load side of the switch from lightning surges.

In this way, since this switch has the lightning arrester element 16 buried within the movable insulator 13, there is no need to enlarge the switch case 1, and the switch becomes a compact switch with a built-in lightning arrester element. Also, simply switch case 1
Unlike when the lightning arrester element is directly attached and fixed to the
Since there is no need to arrange lead wires, etc. connected to the charging side and grounding side electrodes of the lightning arrester element inside the case, the inside of the switch case 1 has a simple configuration, and therefore,
The switch case can also be easily assembled.

Effects of the device As detailed above, this device insert-moldes a movable contact blade so that it passes through the rotational axis of a movable insulator integrally molded with synthetic resin at almost right angles, and is immovable relative to the movable insulator. In a rotary switch equipped with a rotating shaft that rotates a movable insulator to open and close, a charging side electrode of the movable insulator is electrically connected to the movable contact blade, and a grounding side electrode is electrically connected to the rotating shaft. By embedding the lightning arrester elements that are connected to each other, it is possible to easily assemble and manufacture the switch case without increasing the size of the switch case itself, making it an excellent idea for industrial use.

[Brief explanation of drawings]

Fig. 1 is a partially sectional front view of a movable electrode showing an embodiment embodying the present invention, Fig. 2 is a side view thereof, Fig. 3 is an exploded perspective view showing only the support mechanism of the movable electrode, and Fig. 4 is a perspective view showing the connected state of the lightning arrester element, FIG. 5 is a cross-sectional view showing the attached state of the connecting ring, FIG. 6 is a perspective view of the grounding fitting, FIG. 7 is a cross-sectional view of the movable electrode, and FIG. FIG. 2 is a vertical cross-sectional view showing a movable electrode for one phase. DESCRIPTION OF SYMBOLS 1... Case, 8, 9... Rotating shaft, 13... Movable insulator, 14... Movable contact blade, 16... Lightning arrester element, 23... Connection ring, 25... Grounding metal fitting.

Claims (1)

[Scope of utility model registration request] A movable contact blade is insert-molded so as to pass almost orthogonally through the axis of rotation of a movable insulator integrally molded with synthetic resin and cannot move relative to the movable insulator, and a rotary shaft for opening and closing the movable insulator relative to the same movable insulator is provided. In the attached rotary switch, a lightning arrester element is embedded in the movable insulator, the charging side electrode being electrically connected to the movable contact blade, and the grounding side electrode being electrically connected to the rotating shaft. A rotary switch with a built-in lightning arrester element.