JPS62213106A - On-load tap changer - Google Patents

Abstract

PURPOSE:To prevent friction and wear of contacts, by arranging a plural number of roller-shape contacts between a fixed contact and a collector ring so that sliding contact is improved into rolling contact. CONSTITUTION:A collector ring 2 is fixed on an insulating cylinder 10, the first roller-shape movable contact 3a rotates with one end being in contact with the collector ring 2 and the other end being in contact with the second roller-shape movable contact 3b, and the rotating support pins 11 of the first and second roller-shape movable contacts move along the sliding grooves 8a and 8b mounted on a holder 14. While contact pressure necessary for the fixed contact 1 is given by compressive springs 6, a change in diameters according to the ration of the contact point radius, which is from the rotational center of the first and second roller-shape contacts 3a and 3b and the holder 14 to the collector ring 2, to the contact point radius, which is to the fixed contact 1, enables both to become equal in contact and rotation speed, and therefore not being accompanied by a sliding action. Thus, capacity of making the movable contacts can be reduced, and friction and wear of the contacts become preventible.

Description

DETAILED DESCRIPTION OF THE INVENTION OBJECTS OF THE INVENTION Field of Industrial Application The present invention relates to improvements in tap winder contacts for selecting taps in transformer tap windings.

(Prior Art) As this type of contact device, one having a structure as shown in FIGS. 4 and 5 has been generally used. That is,
A fixed contact 1 and a current collecting contact 2 having a half-surface contact part,
A pair of movable contacts 3a and 3b bridge these and sandwich them from above and below, and a movable contact 3a and a pin 4 are connected to each other.
Spring 5a that presses 3b.

5b.

In normal cases, fixed contacts 1 are arranged at equal intervals on the circumference or in a straight line, and these fixed contacts 1 are connected to a pair of movable contacts 3a,
3b is configured to be selected while sliding.

(Problems to be Solved by the Invention) In a contact device having such a structure, friction occurs between each contact point due to sliding, and a secondary phenomenon such as wear occurs. This tendency increases as the capacity of the contact increases, as the spring force applied between the fixed and movable contacts increases. This metal powder naturally scatters inside the transformer, and it is clear that it is harmful to the internal insulation of the transformer.

In recent years, equipment has tended to become larger and there has been a strong desire to solve this problem.

The present invention takes into account two problems, and aims to provide a tap selector that can reduce the closing force of movable contacts without reducing the contact pressure, and can prevent friction and wear of the contacts. be.

(Means for Solving the Problems) In order to solve this problem, the present invention provides a plurality of roller type contacts between the fixed contact and the current collecting ring, and improves the conventional sliding contact to a rolling contact. It is designed to minimize wear during operation.

(Function) That is, the first roller-type movable contact rolls in contact with the current collection ring, and the second roller contacts the first roller-type movable contact with one end and rolls, and the other end contacts and rolls with the fixed contact. The first roller-type movable contact contacts and rolls on the surface of the current collecting ring, and the second roller-type movable contact contacts and rolls on the surface of the fixed contact 1 due to the rotational movement of the holder. Therefore, no sliding action is performed. Therefore, wear can be eliminated.

In the roller type movable contacts shown in FIGS. 1 and 2, since the transfer speed on the current collecting ring and the transfer speed on the fixed contact must be the same, their diameters are changed according to the rotation radius ratio.

(Example) Embodiments of the present invention will be described using FIGS. 1 to 3.

The current collecting ring 2 is fixed on the cylinder of the insulating cylinder 1o.
3a is a first roller-type movable contact that rolls in contact with the current collecting ring 2 at one end and a second roller-type movable contact 3b at the other end.

Reference numeral 11 designates transfer fulcrum pins for the first and second roller-type movable contacts, which move along sliding grooves 8a and 8b provided in the retainer 14. Reference numeral 15 denotes a ball bearing, which is provided to ensure smooth rotation of each of the first and second roller-type movable contacts 3a, 3b.

Reference numeral 1 denotes a fixed contact whose one end contacts the second roller-type contact 3b. The other end is connected to a tap lead of a tap winding (not shown). , 17 is a holder for holding the identification contact 1 and is fixed to the insulating cylinder 9. 6 is a compression spring that applies the necessary contact pressure to the fixed contact 1; first and second roller type contacts 3;
By changing the diameter according to the ratio of the radius of the point of contact between a and 3b and the center of rotation of the retainer 14 with the current collecting ring 2 and the radius of the point of contact with the fixed contact, the contact and transfer speed between the two can be made the same. Therefore, there is no need for sliding action as in conventional devices.

〔Effect of the invention〕

By implementing the present invention described above, the following effects are produced.

(υ) The generation of metal wear particles can be suppressed by improving the conventional sliding contact to a rolling contact.

(2) The improvement from sliding contact to rolling contact greatly reduces frictional force, which reduces the driving force that drives the movable contact and allows the overall size to be reduced.

- Since the generation of metal powder can be suppressed, there is no effect on the internal insulation of the transformer, and unlike conventional equipment, there is no need to install a device to prevent metal powder from scattering, so it can be manufactured at a low cost.

[Brief explanation of drawings]

Figures 1 to 3 are explanatory diagrams showing one embodiment of the present invention.
The figure is a plan view, FIG. 2 is a sectional view taken along the line A-B in FIG. 1, FIG. 3 is a sectional view taken along line A-B in FIG. 1, and FIG. 3 is a diagram showing a two-stage arrangement, and FIG. 4 is a sectional view showing a conventional device. FIG. 5 is a sectional view taken along line XX in FIG. 4. DESCRIPTION OF SYMBOLS 1... Fixed contact, 2... Current collector contact (ring) 3a/3b... Movable contact, 4... Movable retainer 5... Bearing, 6... Compression spring 7...
・Fixing retainer. Agent Patent Attorney Noriyuki Chika Yudo Hirofumi Mitsumata Figure 1 Figure 2 Figure 4 Figure 5

Claims (2)

[Claims] (1) In an on-load tap changer consisting of a plurality of fixed contacts connected to the taps of the tap winding and a movable contact that contacts the fixed contacts, a first roller type that rolls in contact with the current collector ring. a second roller contact that rolls in contact with a first roller contact at one end and a fixed contact at the other end;
a fixed contact that rolls in contact with the roller type contact and is connected to the transformer tap winding; and a compression spring that applies contact pressure to the fixed contact at a point of contact with the first and second roller type contacts. An on-load tap changer characterized by: (2) The on-load tap according to claim 1, wherein the diameter ratio of the first roller type contact and the second roller type contact is made proportional to the radius ratio of the contact point between the current collecting ring and the fixed contact. Switch.