HU207604B - Medium voltage post switch with snap auxiliary contacts - Google Patents

Abstract

A support plate (12) is attached to the stationary main contact (1) of the column switch according to the invention and a snap-in auxiliary contact (13) is attached thereto, which is a prestressed coil spring (13a) resting on a protruding curve (13b) on a damping plate (14). (2) a tensioning auxiliary contact (15) is connected to a rotating shaft (16), which may rotate about the length of the movable main contact (2), depending on the length of the curved track (18). The tensioning auxiliary contact (15) and a tension spring (17) are connected directly to the actuating lever (3). Figure 20 EN 207 604 Scope of the description: 10 pages (including 5 sheets)

Description

BACKGROUND OF THE INVENTION The present invention relates to a medium voltage pole switch with snap-on auxiliary contacts, which has a high switching speed and thus good current interruption and has the particular advantage of self-de-icing the switch in winter, before separating the contacts.

Generally, the design of pole switches for medium voltage overhead lines is that the circuit breaker of the switch is performed by auxiliary arc-pulling contacts connected in parallel with the main contacts. The basic function of this design method is to provide a quick, instantaneous disconnect, and thus secure a safe - no-ignition arc extinguishing.

Many designs are known, the simplest of which is to attach a flexible steel (or bronze) bar to the movable main contact, the tapered end of which engages the hook on the stationary contact when the switch is closed, and only after the main contacts are disengaged Who.

In the solution disclosed in Hungarian Patent Application No. 205675, sufficient flexibility of the moving contact arc drawing device is provided by having a U-shaped spring contact and secured by a spiral spring pre-tensioned arc drawing rod. The U-shaped spring contact also serves to limit the movement (vibration) of the arc drawing rod.

Patent application HU 156548 discloses a solution in which a particularly high speed movement of the auxiliary pulling contact - and thus a quick arcing - is ensured by its movable auxiliary contact being a screw spring ending in a wand and a movable auxiliary contact by a fork the other branch is bent in a loop between the two forks, thereby providing a movable, oblique stop for the moving arcing contact. slides. When switching off, first the hinged main contacts are disconnected, and then the auxiliary contact also pops out of the fork, making a vibratory movement perpendicular to its direction of travel, thereby significantly increasing the switching path. The base of the resulting electric arc is forced to move rapidly according to the high-speed vibration movement; the arc remains at the end of the wand, and its rapid quenching is facilitated by the vortex of air behind the wand.

The disadvantage of this known solution is that the arcuate contact can be trapped in the elaborate auxiliary contact, which is essentially a loop, of a complicated design, thus rendering the switch disconnected.

The Hungarian patent application HU 190185 discloses a solution in which the auxiliary arc pulling pin is rigidly fixed to the movable main contact and a pre-tensioning device is incorporated into the movable main contact itself.

At a well-defined moment when the switch is opened, virtually independently of the operator's intent and dexterity, this ensures that the movable contact will pop out of the locking element formed on the stationary contact and thereby break the circuit.

The disadvantage of this ingenious solution is that the high-mass moving contact requires excessively high energy to achieve the correct break contact speed.

In the process of the present invention, we aim to develop a new coupling device which combines the advantages of the prior art solutions without their drawbacks - that is, it provides a quick, reliable and low switching power interruption and, at winter, also de-icing the switch.

The present invention is based on the discovery that both auxiliary contacts must be movable, such that at the time of disconnection, an independent, fast, bouncing motion in the opposite direction is made when the disconnection begins and when the circuit is interrupted. (So we interrupted the general practice of having one of the pairs of contacts connected.)

Accordingly, the present invention provides a column switch having auxiliary arc pull contacts, one of which is connected to the stationary main contact and the other to the movable master contact.

The movable main contact of the column switch is pivotally secured to a support insulator via an actuating arm and is connected to the actuating arm by a known actuating push rod. In addition, a leaf spring supporting the movable main contact is attached to the operating lever. It also has a known design with a stationary main contact resting on the support insulator.

A fundamental new feature of the column switch according to the present invention is that a support plate is fastened to its stationary main contact with a snap-on auxiliary contact terminating in a curved rod at one end and a screw spring at the other end. The end of the curved rod of the snap-on contact is positioned on a resilient damping plate, also attached to the support plate.

A further feature of the mast switch according to the invention is that its movable main contact has a tensile auxiliary contact terminating in an elastic rod that is pivotally secured to a position on the actuating lever by means of a tension spring and a hook at the end of the elastic rod.

In the present invention, preferably, the support plate fixed to the stationary contact has a hole circle around the pin guiding the screw spring, the end of the screw spring being releasably secured to each hole and the screw spring is threaded onto a pin projecting from the support plate.

It is also advantageous to have a flat plate at the end of the tongue auxiliary contact connected to the movable main contact and having a through hole and an arcuate path (opening) in the plane e.

EN 207 604 Β pins the flat plate - and thus the auxiliary pulling pin - is fixed to the movable pin by rotating between two limit positions.

In the pole switch of the present invention, the movable main contact is preferably connected directly to a (rear) electrical connection point on the support insulator by means of a flexible cable.

In a preferred embodiment of the column switch according to the invention, the actuating arm is of rectangular section and the movable main contact is a copper rail.

The structure and operation of the column switch according to the invention will now be described, with reference to the drawings, in which:

Figure 1 is a side view showing the main structural members of the column switch, a

Fig. 2 illustrates the design of a snap-on auxiliary contact connected to a stationary main contact, a

Figure 3 illustrates the configuration of a tongue auxiliary contact connected to a moving main contact, while

4-7. Figures 1 to 5 show the positions of the contacts in successive phases of the column switch actuation, thereby illustrating the operating principle of the switch,

Figure 8 is an enlarged detail of Figure 6.

As shown in Figure 1, the stationary main contact of the column switch (1) of the invention is rigidly fixed to a support insulator (5). Also connected to a support insulator (5) is the actuating arm (3) of its main contact (2) which is movable via a hinge (4); and the movable main contact (2) is connected to the operating lever (3) via a pivot point (8). A pivot rod (7) for actuating the column switch is connected to the operating lever (6) by means of an articulated shaft (6); and, in order to ensure good conductivity, the movable main contact (2) is directly connected to the terminal by means of a flexible cable (10) with a connection point (11) on the support insulator (5) to which a phase conductor of the free-wire network is connected.

Further, a leaf spring (9) is attached to the operating lever (3) extending below the movable main contact (2).

The basic new features of the solution are the design of arc-auxiliary contacts and the use of auxiliary contacts. they are connected to the standing contacts (1) and the movable main contacts (2).

On the support insulator (5) of the stationary main contact (1), a support plate (12) is fixed to the stationary main contact (1) arranged parallel to the switching plane (motion plane) of the movable main contact (2).

The support plate (12) is provided with a protruding pin (19) around which a hole circle (20) is formed. A coil spring (13a) is fastened to the pin (19) of the holding plate (12), one end of which is pre-tensioned by a screw (20b) through a hole (20a) in the hole circle (20a). (These details are shown in Figure 2a, 2b.)

The other end (13b) of the coil spring (13a) is formed as a curved rod and its end is mounted on a damping plate (14) fixed to the support plate (12). The coil spring (13a), which is prestressed to the support plate (12) and terminates in a curved rod (13b), forms the snap-in contact (13) of the present invention.

The auxiliary contact, the auxiliary contact (15), is also pivotally secured to the movable main contact (2). At the end of the tongue auxiliary contact (15), connected to the movable main contact (2), a flat plate (15a) is formed on which a hole and a curved path (18) are formed.

In order to connect the plane (15a) - and thus the auxiliary pulling contact (15) - to the movable main contact (2) in the hole or in the curved path (18), a rotary shaft (16); The pin (21) is threaded so that the auxiliary contact (15) can pivot about the rotary axis (16) according to the length of the curved path (18).

The other end of the auxiliary pulling contact (15) is formed as a rod (15b), at the end of which is formed a hook (15c), for example welded to the rod (15b). [The configuration of the rod (15b) ending in the hook (15c) is shown in Figure 3.]

The auxiliary contact (15) is connected to a support bracket (26) by means of a tension spring (coil spring) on the operating lever (3). A plurality of attachment points are provided on the support bracket (26) for adjustably prestressing the tension spring (17).

Figure 1 illustrates a column switch according to the invention when closed. In this way, the movable main contact (2) is in contact with the stationary main contact (1) in a known manner, while being supported by the leaf spring (9). The auxiliary contact (13) is also in its resting position, with the end of its curved rod (13b) resting on the elastic damping plate (14), and the auxiliary contact (15) extending under the curved rod (15b) with its hook (15b).

Figures 2a, 2b illustrate the mounting of the snap-in contact (13) of the present invention on the support plate (12) described above. Depending on which hole (20a) is connected to the end of the coil spring (13b), the biasing of the coil spring (13b) and thereby the auxiliary contact (13) can be controlled.

Fig. 3 shows the relative position of the auxiliary contact (13) and the auxiliary contact (15) at the moment of activation. The end of the curved rod (13b) of the auxiliary auxiliary contact (13) rests on the damping plate (14) (which is pressed depending on the degree of prestressing). When actuated, the auxiliary stick (15b) of the movable auxiliary contact (15b) moving with the movable main contact (2) approaches the curved stick (13b) from the direction (A) shown and moves it laterally (B). The hook (15c) formed at the end of the flexible rod (15b) forms a constrained path for the curved rod (13b) which, when it reaches the end of the hook (15c), elastically bounces in the indicated direction (B). 15c) in the V-shaped opening of the hook. The hook (15c) is configured as shown in the figure to allow movement only in the indicated direction. The opposite end of the hook (15c) prevents the arcuate rod (13b) of the auxiliary contact (13) from being pushed to the other side. In this way, the jamming is always done safely.

4-7. In the diagrams, you can monitor the operation of the column switch by showing each phase of the decoupling.

HU 207 604 Β

In the drawings, in which the structure of the column switch corresponds to the structure shown in Fig. 1, only those structural elements which play an active role during operation are indicated by reference.

Fig. 4 corresponds to Fig. 1 and shows the closed position of the column switch when the snap-on contact 13 is resting on the V-shaped opening of the hook 15c of the auxiliary contact 15 and the damping member 14 with its curved rod 13b. lying on a sheet.

When disconnected, when the push rod (7) is moved upwards, the operating lever (3) is also rotated about the hinge (4), and the hinge (8) is also moved without detaching the movable main contact (2). 1) consisting of a main contact. Any ice deposits will be broken by this "wrist" movement. By pushing upward on the push rod (7), the moving main contact (2) moves almost horizontally on the stationary contact (1) - but has not left it yet - and by moving it also breaks the ice on the stationary contact (1).

With the further pressure of the push rod (7), the movable main contact (2) is already moved upwardly, while the hook (15c) of the pulling contact (15) connected to it also carries the prestressed arc (13b) of the auxiliary contact (13).

Figure 5 shows the moment when the connection between the stationary contact (1) and the moving contact (2) is still present.

When the push rod (7) is moved further upward, the connection between the movable main contact (2) and the stationary main contact (1) is broken; the circuit is closed only between the auxiliary snap contact (13) and the auxiliary contact (15).

The movable main contact (2) leaving the stationary main contact (1) takes the direction of the operating lever (3) under pressure of the leaf spring (9) while the auxiliary contact (15) extends around the rotary axis (16) to the outermost point of the curved path (18). turns freely. The hook (15c) of the pulling contact (15) always maintains a secure connection between the prestressed snap contact (13) and the pulling contact (15) and slides through it to remove any ice that may have formed. During this movement, the tension spring (17) is also in a prestressed state.

Fig. 6 shows the moment when the hook (15c) reaches the end of the curved rod (13b) of the auxiliary contact (13). (The detail shown in the figure is enlarged by Fig. 8.) As the push rod (7) is further raised, the end of the curved rod (13b) leaves the hook (15c) and biases in the direction (D) shown and then rests on 14) damping sheet. (This condition is illustrated in Figure 7a.)

The pulling auxiliary contact (15), after being released from the hook (15c) by the bouncing auxiliary contact (13c), also causes the biasing pulling spring (17) to make a quick, snap-action and to stop at the extreme position shown in Fig. 7b. This position, which is self-locking, is stabilized by the leaf spring (9) and the tension spring (17) and can only be resolved by external force, by moving the push rod (7) downwards. Thus, extinguishing the arc is rapid, definite, and no recapture can occur.

In Fig. 8, which is an enlarged detail (E) of Fig. 6, the end of the curved rod (13b) of the snap-on contact (13) and the end (15b) of the pulling auxiliary (15c) on the hook are shown. moment before. By moving the auxiliary contact (15) in the indicated direction (C), it carries the auxiliary contact (13) until it ends out of the hook (15c) - and then the biasing causes a quick, opposite (D) bounce. on,

By adjusting the preload of the snap-on auxiliary contacts (13) and the auxiliary contacts (15), it is ensured that all three phases are interrupted at the same time.

In summary, the present invention provides a simple, long-life switching mechanism that operates safely under extreme weather conditions.

Claims (3)

PATENT CLAIMS 1. Medium-voltage pole switch with snap-on auxiliary contacts having fixed and movable auxiliary contacts connected to auxiliary insulators and auxiliary arc-drawing contacts connected thereto, and a movable auxiliary contact having an actuating sliding rod and a supporting flap, connected to the movable main contact (2) by means of a rotary shaft (16), auxiliary contact (15) pivoting between two extreme positions and terminating in a pin (15b) provided with a hook (15c) which is provided with a tension spring (17) 3) it is also connected; furthermore, a support plate (12) is fastened to the stationary main contact (1) and preloaded on said support plate (12) by a snap-on contact (13) consisting of a coil spring (13a) and a curved rod (13b) extending therefrom. 13b) its end is resting on a resilient damping plate (14). Column switch according to Claim 1, characterized in that the end of its auxiliary pulling contact (15) connected to the movable main contact (2) is formed as a flat plate (15a) with a bore through the rotary shaft (16) and a curved track (18). ). Column switch according to Claim 1 or 2, characterized in that it is a column switch. that its movable main contact (2) is directly connected to a network connection point (11) on the support insulator (5) by means of a flexible cable (10).