Vacuum arc-extinguishing chamber for segmenting electric arc by using multiple contact pieces

Abstract

The invention discloses a vacuum arc-extinguishing chamber for segmenting an electric arc by using a plurality of contact pieces, n + 1 vacuum short gaps which are approximately connected in series are artificially constructed by additionally arranging n contact pieces between a moving end electrode contact and a static end electrode contact of the vacuum arc-extinguishing chamber, and n is greater than or equal to 2. During closing, the contact piece is clamped between the moving end electrode contact and the static end electrode contact, and the moving end electrode contact, the contact piece and the static end electrode contact are in close contact to realize normal through-flow; during opening, after the moving end electrode contact acts, the contact piece naturally falls under the action of gravity and stops between the two contacts due to the elastic force of the double-hook spring and the pulling force of the hanging ring, the vacuum gap is divided into n + 1 fractures which are approximately connected in series, and the saturation effect existing in the vacuum long gap is relieved.

Description

Technical Field

[0001] The invention belongs to the technical field of vacuum arc extinguishing chambers, and in particular relates to a vacuum arc extinguishing chamber which utilizes a plurality of contact pieces to divide an arc. Background Art

[0002] Vacuum switches have been widely used in medium and low voltage systems due to their strong arc extinguishing ability, fast dielectric recovery speed and environmental friendliness. However, there is a nonlinear saturation effect between the vacuum gap and the breakdown voltage. As the gap size increases, the breakdown voltage increases slowly, which restricts the development of single-break vacuum circuit breakers into the high voltage field.

[0003] Connecting multiple vacuum short gaps in series to form a multi-break vacuum circuit breaker is one of the effective ways to increase the voltage level of the circuit breaker. By setting multiple breaks in a switch, each break can bear a smaller voltage and current, thereby improving the overall breaking performance. However, there are still many difficulties and challenges in its large-scale promotion and application, such as solving the problems of the dispersion of mechanical linkage mechanisms, uneven voltage distribution of breaks, and low integration level. Summary of the invention

[0004] In order to solve the problems existing in the prior art and improve the insulation level of a single-break vacuum interrupter, the purpose of the present invention is to provide a vacuum interrupter that utilizes multiple contact pieces to divide the arc. The present invention installs n contact pieces between the moving-end electrode contact and the stationary-end electrode contact of the vacuum interrupter, and divides the vacuum gap into n+1 approximately series-connected breaks when breaking the arc, thereby fully utilizing the insulation and arc-extinguishing capabilities of each short vacuum gap, alleviating the saturation effect of a long vacuum gap, and thereby effectively improving the voltage tolerance and breaking level of the vacuum interrupter.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] A vacuum interrupter that utilizes a plurality of contact pieces to divide an arc, wherein n contact pieces 2 are installed between a moving electrode contact 3 and a stationary electrode contact 5 of the vacuum interrupter, wherein n≥2, and when the arc is interrupted, n+1 approximately series-connected short vacuum gaps are formed between the moving electrode contact 3 and the stationary electrode contact 5 of the vacuum interrupter through isolation by the contact pieces 2, thereby effectively alleviating the saturation effect of a long vacuum gap and improving the voltage tolerance and interruption level of the vacuum interrupter.

[0007] Preferably, the n contact pieces 2 are coaxially arranged, which will simplify the structural design and manufacturing process, reduce the requirements for precise alignment, and reduce the difficulty of manufacturing; a contact piece buckle 6 evenly distributed along the circumference extends from the edge of each contact piece, and a circular hole is provided on the contact piece buckle 6 for fixing the double hook spring 8; the inner wall of the shielding cover 9 also has a shielding cover buckle 1 with circular holes evenly distributed along the circumference.

[0008] Preferably, if n≥3, one or more contact pieces 2 in the middle are connected to the contact piece 2 of the upper layer only through the hanging ring 7, and the contact piece 2 of the upper layer and the contact piece 2 of the lower layer are connected to the shielding cover buckle 1 on the inner wall of the shielding cover 9 through the double hook spring 8. Such a design can conveniently adjust the number of contact pieces by reasonably selecting springs of different types and increasing or decreasing the number of hanging rings; the multiple double hook springs 8 connected to the contact piece 2 of the upper layer are of exactly the same type and specification. After the gate is opened, the tension of the multiple double hook springs 8 and the gravity of the contact pieces 2 of the upper and middle layers offset each other, so that the contact pieces 2 of the upper and middle layers reach a force balance and are suspended between the moving end electrode contact 3 and the static end electrode contact 5; the multiple double hook springs 8 connected to the contact piece 2 of the lower layer are of exactly the same type and specification. After the gate is opened, the tension of the multiple double hook springs 8 and the gravity of the contact piece 2 of the lower layer offset each other, so that the contact piece 2 of the lower layer reaches a force balance and is suspended between the moving end electrode contact 3 and the static end electrode contact 5; after the multiple contact pieces 2 are all balanced in force, they do not contact each other, and there is a gap between them.

[0009] Preferably, the material of the shielding cover ring buckle 1 for fixing the double hook spring on the inner wall of the shielding cover 9 is consistent with the material of the shielding cover 9, which is easy to manufacture; the material of the double hook spring 8 is made of high-quality carbon spring steel, alloy spring steel or non-ferrous metal alloy, which has strong elasticity and fatigue resistance, and is light in weight, has good processing performance and long service life; the material of the hanging ring 7 is made of copper, copper-chromium alloy, copper-tungsten alloy or stainless steel, which can withstand the high temperature of the arc burning process and has strong wear resistance.

[0010] When closing the circuit, the n movable contact pieces 2 are clamped between the moving electrode contact 3 and the static electrode contact 5, and the moving electrode contact 3, the n contact pieces 2 and the static electrode contact 5 are in close contact to achieve normal current flow; when opening the circuit, after the moving electrode contact 3 is actuated, the n contact pieces 2 fall naturally under the action of gravity, and stop between the two contacts due to the elastic force of the double hook spring 8 and the pulling force of the hanging ring 7, dividing the vacuum gap into n+1 fractures that are approximately connected in series, alleviating the saturation effect of the long vacuum gap.

[0011] Preferably, the number of shielding cover ring buckles 1 on each layer of the inner wall of the shielding cover 9 is 3, which can improve the structural stability and alleviate the swaying of the contact piece during the movement.

[0012] Preferably, the contact piece buckle 6 and the shield cover buckle 1 are U-shaped buckles, which have a simple design, a firm connection, and a smooth transition of the U-shaped structure, which helps to reduce the risk of partial discharge in the arc extinguishing chamber.

[0013] Preferably, the material of the contact piece 2 is consistent with that of the moving-end electrode contact 3 and the stationary-end electrode contact 5, so that the addition of the contact piece 2 has the least effect on the current flow during closing.

[0014] Preferably, the number of the contact sheets 2 is three.

[0015] Preferably, the contact piece 2 is a disc-shaped structure, which has a simple manufacturing process and good heat dissipation effect. In addition, due to the symmetry of the disc-shaped structure, a slight rotation or swing during the movement process has little effect on the effect of splitting the arc.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects:

[0017] The present invention provides a vacuum interrupter that uses multiple contact pieces to divide the arc. By adding three contact pieces between the moving end electrode contact and the stationary end electrode contact of the vacuum interrupter, the vacuum gap is divided into four approximately series-connected breaks when the arc is interrupted, which fully utilizes the insulation and arc-extinguishing capabilities of each short vacuum gap, alleviates the saturation effect of the long vacuum gap, and effectively improves the voltage tolerance and breaking level of the vacuum interrupter. Compared with the method of improving the insulation level of multi-break vacuum circuit breakers, the present invention has lower manufacturing costs, simple structure, and is easy to use, and does not require a significant change in the structure of the traditional vacuum interrupter. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments are briefly introduced below.

[0019] Figure 1 The present invention is a cross-sectional schematic diagram of a vacuum interrupter chamber that utilizes a plurality of contact pieces to divide the arc.

[0020] The numbers and names in the figure are as follows:

[0021] Shielding cover buckle-1, contact piece-2, moving end electrode contact-3, porcelain shell-4, static end electrode contact-5, contact piece buckle-6, hanging ring-7, double hook spring-8, shielding cover-9, bellows-10 DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] The object of the present invention is to provide a vacuum interrupter that utilizes a plurality of contact pieces to divide an arc. The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0024] like Figure 1As shown, the vacuum interrupter of this embodiment uses a plurality of contact pieces to divide the arc, including a porcelain shell 4, a shielding cover 9, a static electrode contact 5, a moving electrode contact 3, a bellows 10, a contact piece 2, a hanging ring 7, a shielding cover buckle 1, a contact piece buckle 6 and a double hook spring 8. In this embodiment, the number of contact pieces 2 is three.

[0025] The upper contact piece 2 and the lower contact piece 2 are fixed to the inner wall of the shielding cover by double hook springs 8, and the middle contact piece 2 is connected to the upper contact piece 2 by a hanging ring 7. The three contact pieces 2 are disc-shaped structures and are coaxially arranged. The three double hook springs 8 connected to the upper contact piece 2 are of exactly the same model and specification. After the gate is opened, the tension of the three double hook springs 8 and the gravity of the upper and middle contact pieces 2 offset each other, so that the upper and middle contact pieces 2 reach a force balance and hover between the moving end electrode contact 3 and the static end electrode contact 5. The three double hook springs 8 connected to the lower contact piece 2 are of exactly the same model and specification. After the gate is opened, the tension of the three double hook springs 8 and the gravity of the lower contact piece 2 offset each other, so that the lower contact piece 2 reaches a force balance and hovers between the moving end electrode contact 3 and the static end electrode contact 5. After the three contact pieces 2 are all balanced in force, they do not contact each other, and a certain gap is left between them.

[0026] When closing the circuit, the three movable contact pieces 2 are clamped between the moving electrode contact 3 and the static electrode contact 5, and the moving electrode contact 3, the three contact pieces 2 and the static electrode contact 5 are in close contact to achieve normal current flow; when opening the circuit, after the moving electrode contact 3 is actuated, the three contact pieces 2 fall naturally under the action of gravity, and stop between the two contacts due to the elastic force of the double hook spring 8 and the pulling force of the hanging ring 7, dividing the vacuum gap into four approximately series-connected breaks, alleviating the saturation effect of the long vacuum gap.

[0027] In summary, the vacuum interrupter provided by the present invention utilizes multiple contact pieces to divide the arc, artificially constructs multiple vacuum short gaps that are approximately connected in series, fully utilizes the excellent characteristics of the vacuum short gap, and effectively alleviates the saturation effect of the vacuum long gap. It has a simple structure, is easy to use, and has a low manufacturing cost. It does not require a significant change in the structure of the traditional vacuum interrupter to enable the interrupter to obtain a higher voltage tolerance characteristic.

[0028] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A vacuum interrupter using multiple contact pieces to divide the arc, characterized in that: N contact pieces (2) are installed between the moving electrode contact (3) and the stationary electrode contact (5) of the vacuum interrupter, wherein n≥2. When the arc is interrupted, n+1 approximately series-connected short vacuum gaps are formed between the moving electrode contact (3) and the stationary electrode contact (5) of the vacuum interrupter through isolation by the contact pieces (2), thereby effectively alleviating the saturation effect of the long vacuum gap and improving the voltage tolerance and interruption level of the vacuum interrupter.

2. A vacuum interrupter using a plurality of contact pieces to divide the arc according to claim 1, characterized in that: The n contact pieces (2) are coaxially arranged; a contact piece buckle (6) evenly distributed along the circumference extends from the edge of each contact piece, and a circular hole is provided on the contact piece buckle (6) for fixing a double hook spring (8); and the inner wall of the shielding cover (9) also has a shielding cover buckle (1) with circular holes evenly distributed along the circumference.

3. A vacuum interrupter using a plurality of contact pieces to divide the arc according to claim 2, characterized in that: If n≥3, one or more contact pieces (2) in the middle are connected to the contact pieces (2) in the upper layer only through the hanging ring (7), and the contact pieces (2) in the upper layer and the contact pieces (2) in the lower layer are connected to the shielding cover buckle (1) on the inner wall of the shielding cover (9) through the double hook spring (8); the multiple double hook springs (8) connected to the contact pieces (2) in the upper layer are of the same model and specification, and after the switch is opened, the pulling force of the multiple double hook springs (8) and the gravity of the contact pieces (2) in the upper layer and the middle layer cancel each other out, so that the contact pieces (2) in the upper layer and the middle layer are 2) to achieve force balance and to suspend between the moving electrode contact (3) and the static electrode contact (5); the multiple double hook springs (8) connected to the contact piece (2) at the lower layer have the same model and specification. After the switch is opened, the pulling force of the multiple double hook springs (8) and the gravity of the contact piece (2) at the lower layer cancel each other out, so that the contact piece (2) at the lower layer achieves force balance and suspends between the moving electrode contact (3) and the static electrode contact (5); after the multiple contact pieces (2) are all balanced in force, they do not contact each other and a gap is left between them.

4. The vacuum interrupter using a plurality of contact pieces to divide the arc according to claim 3, characterized in that: The material of the shielding cover buckle (1) for fixing the double hook spring on the inner wall of the shielding cover (9) is consistent with the material of the shielding cover (9), which is easy to manufacture; the material of the double hook spring (8) is made of high-quality carbon spring steel, alloy spring steel or non-ferrous metal alloy; the material of the hanging ring (7) is made of copper, copper-chromium alloy, copper-tungsten alloy or stainless steel.

5. The vacuum interrupter using a plurality of contact pieces to divide the arc according to claim 2, characterized in that: When the switch is closed, the n movable contact pieces (2) are clamped between the moving electrode contact (3) and the static electrode contact (5), and the moving electrode contact (3), the n contact pieces (2) and the static electrode contact (5) are in close contact to realize normal current flow; when the switch is opened, after the moving electrode contact (3) is actuated, the n contact pieces (2) naturally fall down under the action of gravity, and stop between the two contacts due to the elastic force of the double hook spring (8) and the pulling force of the hanging ring (7), thereby dividing the vacuum gap into n+1 fractures that are approximately connected in series, thereby alleviating the saturation effect existing in the long vacuum gap.

6. The vacuum interrupter using a plurality of contact pieces to divide the arc according to claim 2, characterized in that: The number of shielding cover ring buckles (1) on each layer of the inner wall of the shielding cover (9) is 3.

7. The vacuum interrupter using a plurality of contact pieces to divide the arc according to claim 2, characterized in that: The contact piece buckle (6) and the shield cover buckle (1) are U-shaped buckles.

8. The vacuum interrupter using a plurality of contact pieces to divide the arc according to claim 1, characterized in that: The material of the contact piece (2) is consistent with that of the moving-end electrode contact (3) and the stationary-end electrode contact (5), so that the addition of the contact piece (2) minimizes the impact on the flow of current during closing.

9. The vacuum interrupter using a plurality of contact pieces to divide the arc according to claim 1, characterized in that: The number of the contact sheets (2) is three.

10. The vacuum interrupter using a plurality of contact pieces to divide the arc according to claim 1, characterized in that: The contact piece (2) is a disc-shaped structure.

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