A breaking device

Abstract

The present invention relates to a disconnecting device, comprising an arc extinguishing chamber assembly and a moving contact assembly, with the moving area of ​​the moving contact assembly as the contact area, and also comprising a gas circulation channel, wherein the gas circulation channel can guide at least a part of the airflow rushing out of the arc extinguishing chamber assembly back to the contact area, and the airflow is cooled during the flow. After the insulation strength is restored, on the one hand, the arc is further pushed to move toward the arc extinguishing chamber, and on the other hand, since the air insulation strength of the airflow has been restored, the insulation medium strength of the contact area is enhanced, so that the contact area is not easily ionized and broken down by the voltage at both ends of the contact, thereby preventing the arc from reigniting.

Description

Technical Field

[0001] The present invention relates to a breaking device, and in particular to an improvement of an arc extinguishing system therein. Background Art

[0002] A circuit breaker generally includes a base, a static contact, a moving contact and an arc extinguishing chamber. When the circuit breaker is disconnected, an arc is generated between the moving and static contacts, which is extinguished by the arc extinguishing chamber, and the free gas is discharged from the arc extinguishing chamber to the outside of the base. In this conventional structure, since the arc is discharged from the arc extinguishing chamber to the outside of the product, the pressure in the contact area (the moving area of ​​the moving contact) is reduced. Under the action of the external atmospheric pressure, the arc is easy to return to the contact area and reignite, affecting the arc extinguishing ability of the product; moreover, after the arc is ignited in the contact area, the temperature is still relatively high and the degree of gas ionization is relatively high. Under the action of the electric field generated by the power supply voltage applied at both ends of the contacts, the gas is easy to re-ionize and break down, causing the arc to reignite and the breaking failure. Summary of the invention

[0003] Therefore, in view of the above problems, the present invention proposes a disconnecting device with optimized structure.

[0004] The present invention is implemented by the following technical solutions:

[0005] The present invention proposes a disconnecting device, comprising an arc extinguishing chamber assembly and a moving contact assembly, with the moving area of ​​the moving contact assembly as the contact area, and also comprising a gas circulation channel, which can guide at least a part of the airflow rushing out of the arc extinguishing chamber assembly back to the contact area.

[0006] Among them, in order to make full use of the internal space of the disconnecting device and improve the gas circulation efficiency, in one embodiment, the moving contact assembly is arranged on the first side of the arc extinguishing chamber assembly, and the second side of the arc extinguishing chamber assembly facing away from the moving contact assembly is provided with a diverter cone, and the diverter cone has a first inclined guide surface and a second inclined guide surface, and the first inclined guide surface and the second inclined guide surface can divert the airflow rushing out of the arc extinguishing chamber assembly into two airflows in a first direction and a second direction with directions roughly opposite to each other.

[0007] Among them, in order to form a roughly closed internal circulation channel, prevent the pressure in the contact area from being too low, and use the circulating gas to drive the arc, in one embodiment, the path of the gas circulation channel is roughly divided into two, namely a first circulation path and a second circulation path. The first circulation path is an airflow path composed of a first section along the length of the arc extinguishing chamber assembly on the second side and facing the first direction, a third section along the length of the arc extinguishing chamber assembly on the first side and facing the second direction, and a second section connecting the two. The second circulation path is an airflow path composed of a fourth section along the length of the arc extinguishing chamber assembly on the second side and facing the second direction, a sixth section along the length of the arc extinguishing chamber assembly on the first side and facing the second direction, and a fifth section connecting the two. The third section and the sixth section are connected to the contact area, so that the first circulation path, the second circulation path, the contact area, and the airflow channel of the arc extinguishing chamber assembly form a roughly closed internal circulation channel.

[0008] In order to make the arrangement of the gas circulation channel compact and reasonable, and based on manufacturing and installation considerations, in one embodiment, the disconnecting device includes a base, and the arc extinguishing chamber assembly is installed in the base. The base has an installation gap between the second side of the arc extinguishing chamber assembly and the arc extinguishing chamber assembly, thereby forming the first section and the fourth section, and the second section, the third section, the fifth section, and the sixth section are formed on the base.

[0009] Among them, in order to utilize the relatively concentrated gas generated when the moving and static contacts are just disconnected to further promote the disconnection of the moving and static contacts, in one embodiment, the disconnecting device also includes a static contact, and the moving contact assembly has a movement trajectory relatively close to or away from the static contact to control the conduction or disconnection of the disconnecting device, and the first inclined guide surface of the diverter cone roughly faces the static contact, and the third section of the first circulation path has a first outlet, and the first outlet is arranged on the peripheral side of the static contact and faces the moving contact assembly.

[0010] To prevent the arc from entering the first outlet when the moving and static contacts are just disconnected, in one embodiment, the moving contact assembly includes a baffle, and when the disconnecting device is turned on, the baffle closes the first outlet.

[0011] Among them, in order to take into account both the conductive and arc extinguishing functions and save arc contacts at the same time, in one embodiment, it also includes a static contact, and the moving contact assembly has a first moving contact and a second moving contact that contact and cooperate with the static contact, and the moving contact assembly includes a rotatable bracket, and the bracket is pivotally connected with a plurality of first contact pieces and second contact pieces that are spaced and arranged alternately one by one, the first contact piece has a protrusion on the first moving contact, and the second contact piece has a protrusion on the second moving contact, and the first moving contact and the second moving contact are arranged in a row laterally, wherein the protrusion height of the first moving contact is greater than the protrusion height of the second moving contact, and when the moving contact assembly moves away from the static contact, the second moving contact first breaks contact with the static contact.

[0012] In order to utilize the burning effect of the arc to quickly generate gas and promote the movement of the arc, in one embodiment, the moving contact assembly also includes a contact protection cover, which is made of an insulating gas-generating material and is inserted into the gap between the first contact piece and the second contact piece.

[0013] In order to divide the arc and improve the arc extinguishing efficiency, in one embodiment, the arc extinguishing chamber assembly includes a plurality of insulating arc-isolating plates arranged at intervals, and the insulating arc-isolating plates are arranged toward the moving contact assembly.

[0014] Preferably, the disconnecting device is a circuit breaker or an isolating switch.

[0015] The present invention has the following beneficial effects:

[0016] 1. By setting up a gas circulation channel, the gas rushing out of the arc extinguishing chamber is guided back to the contact area. The airflow is cooled during the flow. After the insulation strength is restored, on the one hand, the arc is further pushed to move to the arc extinguishing chamber. On the other hand, since the air insulation strength of the airflow has been restored, the insulation medium strength of the contact area is enhanced, making it difficult for the contact area to be ionized and broken down by the voltage at both ends of the contact, preventing the arc from reigniting;

[0017] 2. The moving contact assembly provides a first moving contact and a second moving contact arranged in a staggered manner with a height difference, which can take into account both the conduction and arc extinguishing functions, while saving arc contacts;

[0018] 3. A contact protection cover is provided between the contacts to help generate gas and cool the arc. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of a circuit breaker in an embodiment;

[0020] Figure 2 is a schematic diagram of an outer shell of a circuit breaker in an embodiment;

[0021] Figure 3is a schematic diagram of a circuit breaker in an embodiment (including an operating mechanism);

[0022] Figure 4 is a cross-sectional view of a circuit breaker in an embodiment;

[0023] Figure 5 is a schematic diagram of a first circulation path and a second circulation path in an embodiment;

[0024] Figure 6 is a schematic diagram of the circuit breaker in the embodiment just disconnected;

[0025] Figure 7 is a schematic diagram of a baffle closing an air outlet of a first circulation path in an embodiment;

[0026] Figure 8 is a schematic diagram of a moving contact assembly in an embodiment;

[0027] Fig. 9 is a structural exploded diagram of the moving contact assembly in the embodiment;

[0028] Fig.10 Schematic diagram of the cooperation between the moving contact assembly and the static busbar in the embodiment (angle 1);

[0029] Fig.11 Schematic diagram of the cooperation between the moving contact assembly and the static busbar in the embodiment (angle 2);

[0030] Fig.12 is a cross-sectional view of an arc extinguishing chamber assembly in an embodiment;

[0031] Fig.13 1 is a structural exploded view of the arc extinguishing chamber assembly in the embodiment. DETAILED DESCRIPTION

[0032] To further illustrate the various embodiments, the present invention provides drawings. These drawings are part of the disclosure of the present invention, which are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, a person of ordinary skill in the art should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0033] The present invention will now be further described with reference to the accompanying drawings and specific implementation methods.

[0034] This embodiment provides a disconnecting device. For ease of understanding, this embodiment is described by taking a circuit breaker as an example. Figure 1 As shown, the circuit breaker includes a base 1, a moving contact assembly 2, a stationary busbar 3, a moving busbar 4 and an arc extinguishing chamber assembly 5, wherein two bases 1 are joined together to form an outer shell 200 of the frame circuit breaker (see Figure 2), the moving contact assembly 2, the stationary busbar 3, the moving busbar 4 and the arc extinguishing chamber assembly 5 are arranged in the outer shell 200, wherein:

[0035] The static busbar 3 is located above the dynamic busbar 4, and the dynamic busbar 4 is located below the static busbar 3;

[0036] If the moving contact assembly 2 is located on the left side of the arc extinguishing chamber assembly 5 , then the arc extinguishing chamber assembly 5 is located on the right side of the moving contact assembly 2 .

[0037] The moving contact assembly 2 and the arc extinguishing chamber assembly 5 are arranged opposite to each other on the left and right. The arc extinguishing chamber assembly 5 extends up and down along the height direction of the base 1 to make full use of the height dimension of the base, increase the arc running distance, and increase the number of arc extinguishing grids. The static busbar 3 and the moving busbar 4 are respectively arranged at the upper and lower ends of the arc extinguishing chamber assembly 5, and extend outward from the outer shell 200 to become the two terminal terminals of the frame circuit breaker. The static busbar 3 and the moving busbar 4 are separated by the arc extinguishing chamber assembly 5 with height extending up and down, which improves the heat dissipation capacity and avoids heat accumulation between the busbars that are prone to heat. The moving busbar 4 is electrically connected to the moving contact assembly 2. The static busbar 3 extends horizontally first and then extends vertically to form a roughly L-shape. The static busbar 3 has a static contact 31 at the end of the vertical extension section, and correspondingly has a moving contact 21 on the moving contact assembly 2. The moving contact assembly 2 is pivotally connected to the base 1 as a whole, so that the moving contact 21 can swing up and down to approach or move away from the static contact 31 to control the conduction and disconnection of the frame circuit breaker. The frame circuit breaker also includes an operating mechanism 6, see Figure 3 The operating mechanism 6 is arranged on the left side of the moving contact assembly 2. The operating mechanism 6 is installed outside the outer shell 200 and is linked to the moving contact 21 by means of a connecting rod mechanism to drive the contact 21 to move and help the circuit breaker to open and close. The setting of the operating mechanism 6 is a conventional choice and will not be described in detail in this example. In terms of overall layout, in the frame circuit breaker, the moving contact assembly 2 is arranged in the middle, and the operating mechanism 6 and the arc extinguishing chamber assembly 5 are respectively arranged on the left and right sides of the moving contact assembly 2, thereby reasonably utilizing the installation space of the frame circuit breaker.

[0038] See also Figure 4 The right side of the arc extinguishing chamber assembly 5 and the base 1 have an installation gap 14, in which a diverter cone 11 is provided. The diverter cone 11 is integrally formed on the base 1, and the diverter cone 11 has two inclined guide surfaces inclined upward and downward, which can divert the free gas that rushes out of the outside of the arc extinguishing chamber assembly 5 to the right through the arc extinguishing chamber assembly 5 into two air flows in the upward and downward directions, respectively, so as to make full use of the internal space of the circuit breaker and improve the gas circulation efficiency. The moving area of ​​the moving contact assembly 2 is defined as the contact area. The base 1 also has a gas circulation channel to return the gas that rushes out of the outside of the arc extinguishing chamber assembly 5 through the arc extinguishing chamber assembly 5 to the contact area. The gas circulation channel includes a first circulation path 12 and a second circulation path 13, see Figure 5The first circulation path 12 is formed by connecting the first section 123 running up and down, the second section 122 running left and right, and the third section 121 running up and down, the first section 123 is formed by the installation gap 14, and the second section 122 and the third section 121 are formed on the base 1; the second circulation path 13 is formed by connecting the fourth section 133 running up and down, the fifth section 132 running left and right, and the sixth section 131 running up and down, the fourth section 133 is formed by the installation gap 14, and the fifth section 132 and the sixth section 131 are formed on the base 1, and the first circulation path 12 and the second circulation path 13 are connected with the contact area, so that the first circulation path 12 and the second circulation path 13 can be formed by the two sections of the flow diverted by the diverter cone 11. The airflows are respectively guided back to the contact area, and the first circulation path 12, the second circulation path 13, the contact area, and the airflow channels in the arc extinguishing chamber assembly form a roughly closed inner circulation channel. After the airflow is completely deionized by the arc extinguishing chamber assembly 5, it can be fully cooled during the flow in the first circulation path 12 and the second circulation path 13. After the insulation strength is restored, it re-enters the contact area, on the one hand, further pushing the arc to move toward the arc extinguishing chamber, on the other hand, because the air insulation strength of the airflow has been restored, the insulation medium strength of the contact area is enhanced, so that the contact area is not easily ionized and broken down by the voltage at both ends of the contact, preventing the arc from reigniting, and at the same time, it can also prevent the pressure in the contact area from being too small, causing the arc to return to the contact area. Figure 5 The flow paths of the two airflows are shown in FIG. 1 , which can be referred to for easy understanding. In addition, an anti-ionization filter 7 can be provided on the flow path of the airflow to discharge part of the free gas out of the frame circuit breaker to prevent the arc extinguishing chamber from being over-pressured, causing the base to be damaged, and the arc to overflow from the base to the outside of the product.

[0039] In addition, if Figure 6 It is worth noting that the upward inclined guide surface of the diverter cone 11 is roughly arranged facing the static contact 31. Therefore, when the moving contact 21 and the static contact 31 are just disconnected, the opening distance between the moving contact 21 and the static contact 31 is small, and the airflow is relatively concentrated. The airflow rushes to the upward inclined guide surface of the diverter cone 11. At this time, the diverter cone 11 guides most of the airflow to the first circulation path 12. At the same time, the air outlet of the first circulation path 12 is arranged on the peripheral side of the static contact 31 and toward the moving contact assembly 2. Then, under the push of the airflow rushing out of the first circulation path 12, the moving contact 21 and the static contact 31 can be further helped to disconnect.

[0040] See also Figure 5-6 A stopper 15 is formed on the base 1, and the lower end surface of the stopper 15 is an arc surface that matches the baffle 23 on the moving contact assembly 2. During the opening and closing process of the circuit breaker, the stopper 15 and the baffle 23 always cooperate to roughly close the left side of the moving contact 21 and the static contact 31 to prevent the arc from overflowing, and refer to Figure 7In the closed state, the baffle 23 on the moving contact assembly 2 generally closes the first circulation path 12 upwards, preventing the arc from entering the first circulation path 12 when the moving and static contacts are separated, and also preventing the airflow from flowing back. Figure 6 and Figure 8 The upper end of the baffle 23 is an oblique guiding surface. When the airflow flows back out of the contact area from the first circulation path 12, the baffle 23 can also help to redirect the airflow obliquely to the arc extinguishing chamber assembly 5.

[0041] See also Figure 8-11 The moving contact assembly 2 includes a bracket 22, a baffle 23 installed on the bracket 22, and a contact piece 24 pivoted on the bracket 22. The contact piece 24 is composed of a first contact piece 241 and a second contact piece 242 arranged alternately and side by side. The first contact piece 241 has a protruding first moving contact 211, and the second contact piece 242 has a protruding second moving contact 212. The first moving contact 211 and the second moving contact 212 are arranged transversely on the first contact piece 241 and the second contact piece 242 to form a moving contact 21. The first moving contact 211 and the second moving contact 212 have a height difference, such as Figure 10-11 As shown, the height of the second moving contact 212 is greater than the height of the first moving contact 211, so that the second moving contact 212 is closer to the static contact 31 than the first moving contact 211. Fig.10The figure also shows the limit rod 201 and the limit shaft 202 located above and below the contact piece 24 to limit the rotation angle range of the contact piece 24. The first contact piece 241 has a larger rotation range than the second contact piece 242. Therefore, when the circuit breaker is closed, the bracket 22 swings toward the direction close to the static contact 31. Since the second moving contact 212 is higher than the first moving contact 211, the second moving contact 212 first contacts and conducts with the static contact 31. The bracket 22 continues to swing, pushing the first moving contact 211 to rotate around its pivot axis on the bracket 22, so that the first moving contact 211 contacts and conducts with the static contact 31 later. When the circuit breaker is opened, the bracket 22 swings toward the direction away from the static contact 31, and the first moving contact 212 contacts and conducts with the static contact 31. The contact 211 is separated from the static contact 31 first. When the first moving contact 211 and the static contact 31 are just separated, the second moving contact 212 and the static contact 31 are still in the conducting state, so no arc will be generated between the moving and static contacts. When the bracket 22 continues to swing, the second moving contact 212 is separated from the static contact 31, and an arc is generated between the two. Therefore, when disconnecting, the second moving contact 212 is used as an arc starting contact to guide the arc into the arc extinguishing chamber, and the first moving contact 211 is protected as a current-carrying contact. The first moving contact 211 and the second moving contact 212 arranged in a staggered height difference can take into account both the conductive and arc extinguishing functions, while saving arc contacts. A contact protection cover 25 is also installed between the gap between the first contact piece 241 and the second contact piece 242. The contact protection cover 25 is made of insulating gas-generating materials such as nylon, melamine, PA46, etc. When the frame circuit breaker is disconnected, the contact protection cover 25 generates a large amount of gas under the high temperature burning of the arc. On the one hand, it can compress and cool the arc, and on the other hand, it can push the arc to quickly enter the arc extinguishing chamber.

[0042] See also Figure 12-13 The arc extinguishing chamber assembly 5 includes a plurality of arc extinguishing grids arranged in rows and a plurality of vertically extending and spaced insulating arc isolation plates 52 (the insulating arc isolation plates 52 are made of insulating gas-generating materials or insulating materials such as nylon, melamine, PA46, etc.) arranged on one side of the arc extinguishing grid. The insulating arc isolation plates 52 face the moving contact assembly 2. When the arc enters the arc extinguishing chamber, the arc will be divided into several parts by the insulating arc isolation plates 52, and the arc will be compressed and cooled, so that the arc energy is reduced during breaking, thereby improving the breaking reliability.

[0043] Although the present embodiment takes a circuit breaker as an example to illustrate the function of the disconnecting device, in addition to the circuit breaker, the disconnecting device may also be other disconnecting switch structures, such as an isolating switch.

[0044] Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, it should be understood by those skilled in the art that various changes in form and details made to the present invention without departing from the spirit and scope of the present invention as defined in the appended claims will fall within the scope of protection of the present invention.

Claims

1. A breaking device, comprising an arc extinguishing chamber assembly and a moving contact assembly, wherein the moving area of ​​the moving contact assembly is the contact area. Features: It also includes a gas circulation channel and a diverter cone, wherein the moving contact assembly is arranged on a first side of the arc extinguishing chamber assembly, and the diverter cone is arranged on a second side of the arc extinguishing chamber assembly away from the moving contact assembly, and the gas circulation channel can guide at least a portion of the airflow that rushes out of the arc extinguishing chamber assembly and is diverted by the diverter cone back to the contact area.

2. The disconnecting device according to claim 1, Features: The diverter cone has a first inclined guide surface and a second inclined guide surface, which can divert the airflow rushing out of the arc extinguishing chamber assembly into two airflows in a first direction and a second direction that are roughly opposite in direction. The arc extinguishing chamber assembly includes a plurality of arc extinguishing grids arranged in rows.

3. The disconnecting device according to claim 2, Features: The paths of the gas circulation channel are divided into two, namely a first circulation path and a second circulation path. The first circulation path is an airflow path consisting of a first section along the length of the arc extinguishing chamber assembly on the second side and facing the first direction, a third section along the length of the arc extinguishing chamber assembly on the first side and facing the second direction, and a second section connecting the two. The second circulation path is an airflow path consisting of a fourth section along the length of the arc extinguishing chamber assembly on the second side and facing the second direction, a sixth section along the length of the arc extinguishing chamber assembly on the first side and facing the second direction, and a fifth section connecting the two. The third section and the sixth section are connected to the contact area, so that the first circulation path, the second circulation path, the contact area, and the airflow channel of the arc extinguishing chamber assembly form a roughly closed inner circulation channel.

4. The disconnecting device according to claim 3, Features: The disconnecting device also includes a base, in which the arc extinguishing chamber assembly is installed, and the base has an installation gap between the second side of the arc extinguishing chamber assembly and the arc extinguishing chamber assembly, thereby forming the first section and the fourth section, and the second section, the third section, the fifth section, and the sixth section are molded on the base.

5. The disconnecting device according to claim 3, Features: It also includes a static contact, and the moving contact assembly has a movement trajectory relatively close to or away from the static contact to control the conduction or disconnection of the disconnecting device, the first inclined guide surface of the diverter cone roughly faces the static contact, and the third section of the first circulation path has a first outlet, which is arranged on the peripheral side of the static contact and faces the moving contact assembly.

6. The disconnecting device according to claim 5, Features: The moving contact assembly includes a baffle, and when the disconnecting device is turned on, the baffle closes the first outlet.

7. The disconnecting device according to claim 1, Features: It further includes a static contact. The moving contact assembly has a first moving contact and a second moving contact that are in contact and cooperation with the static contact. The moving contact assembly includes a rotatably arranged bracket, and a plurality of first contact pieces and second contact pieces that are pivotally connected to the bracket at intervals and arranged one by one in a staggered manner. The first moving contact is provided with a raised first moving contact on the first contact piece, and the second moving contact is provided with a raised second moving contact on the second contact piece. The first moving contact and the second moving contact are arranged in a row horizontally, wherein the raised height of the first moving contact is greater than the raised height of the second moving contact. When the moving contact assembly is away from the static contact, the second moving contact first disengages from the static contact.

8. The breaking device according to claim 7, characterized in that: the moving contact assembly further includes a contact protection cover, the contact protection cover is made of an insulating gas-generating material, and the contact protection cover is inserted into the gap between the first contact piece and the second contact piece.

9. The breaking device according to claim 1, characterized in that: the arc extinguishing chamber assembly includes a plurality of insulating arc separating plates arranged at intervals, and the insulating arc separating plates are arranged towards the moving contact assembly.

10. The breaking device according to any one of claims 1-9, characterized in that: the breaking device is a circuit breaker or a disconnecting switch.

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