JPH0125174B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a switching switch for a resistive on-load tap changer.

A conventional switching switch of a resistive type on-load tap changer, for example, a rotary type resistive switching switch, has a structure as shown in FIG. 1 of the accompanying drawings. That is, in the figure, reference numeral 1 is an oil-tight insulating cylinder that is an oil-tight container for isolating the contact part of the switching switch from the transformer room, and 2 is an oil-tight insulating cylinder for drawing the current of the switching switch to the transformer side. A penetrating fixed contact is attached to the insulating tube 1, and a contact insulating tube 3 is a fixed contact mount provided inside the oil-tight insulating tube 1. An arcing fixed contact 4 and a resistance fixed contact 5 are provided corresponding to the main arcing movable contact 6 and resistance movable contact 7, and are also provided corresponding to the energizing movable contact 8 and the penetrating fixed contact 2 and penetrating the contact insulating tube 3. An intermediate connection contact 10 is provided. Further, the main arcing movable contact 6, the resistance movable contact 7, and the energizing movable contact 8 are all attached to a rotating link mechanism 9, and the energizing movable contact 8, the main arcing movable contact 6, and the resistance movable contact 7 are opened and closed in a certain order. It operates radially. Furthermore, a connection lead 11 is connected between the intermediate connection contact 10 and the main arcing fixed contact 4.
In addition, the main arcing fixed contact 4 and the resistance fixed contact 5
are connected through a current limiting resistor R.

Because the conventional device was constructed in this way, it had many drawbacks as shown below.

(1) In order to connect the current-carrying movable contact 8 and the penetrating fixed contact 2 attached to the oil-tight insulating cylinder 1, an intermediate connection contact 10 is required, and furthermore, the current-carrying movable contact 8 side of the intermediate connection contact 10 is , energized movable contact 8
In order to maintain stable contact pressure when the contact pressure is applied, the intermediate connection contact 10 is configured to function as a fixed contact without a wipe.
In order to ensure the contact pressure, the penetrating fixed contact side of the It had no choice but to become complicated.
Further, the contact insulating cylinder 3 itself requires processing and parts for attaching the intermediate connection contact.

(2) To insulate the intermediate connecting contact 10 from the adjacent intermediate connecting contact attached to the adjacent phase, connect the intermediate connecting contact 10 to the contact insulating tube 3.
Since the contact insulating tube 3 is attached to the contact insulating tube 3, the contact insulating tube 3 becomes creeping insulation, and in particular, it becomes difficult to ensure the internal dielectric strength voltage of the contact insulating tube 3, which shortens the distance between the intermediate connecting contacts 10. In order to improve such dielectric strength, the inner diameter of the contact insulating tube 3 is increased,
The creepage distance has to be increased, resulting in
The planar dimension of the switching switch as a whole becomes large.

(3) Deformation of the contact insulating tube 3 in the planar direction, that is,
If the perfect circle is distorted or distorted, the contact between the intermediate connecting contact 10 attached to the contact insulating tube 3 and the corresponding current-carrying movable contact 8 and penetrating fixed contact may be damaged. There comes a point where an even situation occurs, resulting in an increase in contact temperature due to a decrease in contact pressure. In order to prevent this, it is necessary to make the contact insulating tube 3 into a nearly perfect circle by machining, etc.
It will be very expensive.

An object of the present invention is to obtain a changeover switch that eliminates the drawbacks of conventional devices, and in order to achieve this purpose, a current-carrying movable contact is inserted into an oil-tight container at the time of contact. The main arcing fixed contact adjacent to the current-carrying movable contact and the fixed penetrating contact are configured to be in direct contact with the fixed penetrating contact attached to the terminal, and a removable connecting contact is provided between the fixed penetrating contact and the fixed penetrating contact adjacent to the energizing movable contact. It is something.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings showing one embodiment thereof.

In FIG. 2, reference numeral 21 denotes an oil-tight insulating cylinder, 2, which is an oil-tight container having the same structure as that of the conventional device.
2 also has the same function as that of the conventional device, but unlike the conventional device, the energizing movable contact 26 is in direct contact and the connection contact 30 is in parallel contact with the penetrating fixed contact, and 23 is a fixed contact mount. A main arcing fixed contact 24 and a resistance fixed contact 25 are provided on its inner surface, and 26 and 27 are connected from the inside corresponding to the main arcing fixed contact 24 and the resistance fixed contact 25. A main arcing movable contact that opens and closes radially and cuts off current, and a resistance movable contact; 28 is an energizing movable contact that makes contact with and leaves the penetrating fixed contact; 29 is a main arcing movable contact 26; a resistance movable contact It is a rotating link mechanism that operates 27 and the energized movable contact 28 in a fixed opening/closing order, and 30 is removably attached to the contact insulating tube 23 and engages between the penetrating fixed contact 22 and the main arcing fixed contact 24. It is a connection contact. In addition, a current limiting resistor R is connected between the main arcing fixed contact 24 and the resistance fixed contact 25.
As is well known, they are connected by connection leads 31, and these are all connected inside the contact insulating tube 23.

The switching switch of the present invention is constructed as described above, but the changes in current within the switching switch and the operation of the switching switch are similar to those of widely known switches. Therefore, its explanation will be omitted here.

In this way, the present invention allows direct contact between the fixed penetrating contact 22 provided through the oil-tight insulating cylinder 21 and the energized movable contact 28, and the fixed penetrating contact 2
Since the connection contact 30 installed between the main arcing fixed contact 24 and the main arcing fixed contact 24 is made removable, the following advantages can be achieved compared to the conventional switching switch. That is, (1) direct contact between the energizing movable contact 28 and the penetrating fixed contact 22 eliminates the need for other contacts connected in series therebetween;
8. The contact resistance value between the penetrating fixed contacts 22 can be reduced, and as a result, the temperature rise of the contact part can be reduced, as well as the contact insulating tube 23
(2) Since the connecting contact 30 is made detachable, the contact insulating tube 23 can be easily hung. (3) The present invention has the effect of simplifying the contact structure of the part. The connection contact 30 has the effect that it can be a connection contact with a small current capacity and a simple structure because current only flows transiently when the changeover switch is switched.(4) Between adjacent phases The insulation has a creepage dimension between the penetrating fixed contacts 22 attached to the inner surface of the oil-tight insulating cylinder 21, which has a larger diameter than the contact insulating cylinder 23, so the creepage distance becomes longer and the reliability of the dielectric strength improves. (5) Since the fixed penetrating contact 22 and the energized movable contact 28 have a direct contact structure, in order to ensure the contact, it is necessary to connect the oil-tight insulating cylinder 21 on which the fixed penetrating contact 22 is provided and the energized movable contact 28. It is only necessary to ensure concentricity when the movable contact 28 meets the contact surface, which has the effect of easily stabilizing the contact stress.
High precision round machining is no longer necessary to correct the deformation, and as a result, it has many effects, including the ability to reduce manufacturing costs.

In addition, in the above embodiment, only the configuration for one phase of the two-resistance type on-load tap changer was explained, but the structure is not limited to this type, and the above embodiment also applies to a three-phase switch. can be applied, and the effect is no different from that of the above embodiment.

Furthermore, in the above embodiments, the container of the switching switch is cylindrical, but of course it is not limited to this shape.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional view of a conventional switching switch, and FIG. 2 is a partial cross-sectional view of an embodiment of the switching switch of the present invention. 1,21...Oiltight container (oiltight insulating tube); 2,2
2... Penetration fixed contact; 3, 23... Fixed contact mount (contact insulator); 4, 24... Main arcing fixed contact; 5, 25... Resistance fixed contact; 6, 26...
...Main arcing movable contact; 7, 27... Resistance movable contact; 8, 28... Current-carrying movable contact; 9, 29...
Rotating link mechanism; 10... intermediate connection contact; 11,
31... Connection lead; 30... Connection contact.

Claims (1)

[Claims] 1 Oil-tight containers, penetrating fixed contacts installed in oil-tight containers, fixed contact mounts housed in oil-tight containers,
In a switching switch for a resistance-type load tap changer equipped with a current-carrying movable contact, a main arcing movable contact, a main arcing fixed contact, etc., when contact is made, the current-carrying movable contact is attached to an oil-tight container by penetrating through it. A switching switch characterized in that it is configured to directly contact a contact and is provided with a detachable connecting contact between a main arcing fixed contact and a penetrating fixed contact adjacent to an energized movable contact.