Contact arc extinguishing device of switch

Abstract

A contact arc extinguishing device of a switch belongs to the technical field of low-voltage apparatuses. Comprising a moving contact, a static contact and an arc extinguish chamber, the moving contact comprises a moving contact piece, a contact cover and a contact support, the moving contact piece is rotatably arranged on the contact support, the contact cover is fixedly installed on the contact support, and the moving contact piece comprises a first moving contact piece; the circuit breaker is characterized in that the first movable contact piece extends upwards after penetrating through the interior of the contact cover, the first movable contact piece is provided with a pivoting hole and a pivoting part located around the pivoting hole, and the inner side of the contact cover is provided with a sealing structure matched with the outer edge of the pivoting part. The advantages are that the sealing structure in the contact cover prevents arc gas from flowing through the inside of the contact cover and contacting a conductor below, thereby preventing breakdown.

Description

Technical Field

[0001] The invention belongs to the technical field of low-voltage electrical appliances, and in particular relates to a contact arc extinguishing device of a switch. Background Art

[0002] As an important low-voltage electrical equipment, the switch realizes the closing and opening control of the carrying current to meet the management of the power supply network. Especially in today's new energy development, the characteristics of the switch are particularly important, which is convenient to adapt to the characteristics of new energy that requires frequent switching of circuits.

[0003] The existing moving contact structure adopts the form of long and short moving contact pieces, in which the second moving contact piece is used to carry the current when the switch is closed, and the first moving contact piece is used to carry the current and start the arc, so that the arc starting is completed by the first moving contact piece. In this arrangement, the arc starting position is located inside the arc extinguishing chamber, which is conducive to the extinguishing of the arc. However, when the arc is generated, the ionized gas containing metal vapor will overflow from the gap around the moving contact piece to the bottom of the moving contact piece under the influence of factors such as the air flow field, and contact the conductor under the moving contact piece, such as the conductive flexible connection, causing breakdown. This problem is also a technical problem that ordinary technicians in this field have always needed to solve. Summary of the invention

[0004] The task of the present invention is to provide a contact arc extinguishing device for a switch, which prevents arc gas from flowing through the inside of the contact cover and contacting the conductor below through a sealing structure inside the contact cover, so as to prevent breakdown.

[0005] The task of the present invention is accomplished in this way. A contact arc extinguishing device for a switch includes a moving contact, a static contact and an arc extinguishing chamber. The moving contact includes a moving contact piece, a contact cover and a contact support. The moving contact piece is rotatably arranged on the contact support. The contact cover is fixedly installed on the contact support. The moving contact piece includes a first moving contact piece; the first moving contact piece explores the interior of the contact cover and extends upward. The first moving contact piece has a pivot hole and a pivot part located around the pivot hole. The inner side of the contact cover has a sealing structure that cooperates with the outer edge of the pivot part.

[0006] In a specific embodiment of the present invention, the sealing structure includes a first matching portion, and the first matching portion is sealingly matched with the front outer edge of the pivoting portion.

[0007] In another specific embodiment of the present invention, the sealing structure further includes a second matching portion, and the second matching portion is sealingly matched with the outer edge of the rear side of the pivoting portion.

[0008] In another specific embodiment of the present invention, the arc extinguishing chamber includes a pair of gas producing parts, an arc channel is formed between the pair of gas producing parts, and the moving contact piece also includes a second moving contact piece; the first moving contact piece extends into the interior of the arc channel, and the second moving contact piece is located on the outside of the contact cover and on the outside of the arc channel.

[0009] In another specific embodiment of the present invention, the contact cover has a raised portion extending toward the arc extinguishing chamber, and a pair of gas producing parts extend downward and isolate a first moving contact piece located on the inner side of the raised portion from a second moving contact piece located on the outer side of the raised portion.

[0010] In another specific embodiment of the present invention, the contact cover also includes a base, the raised portion extends from the base toward the arc extinguishing chamber, the base is an internal hollow shell structure, and the sealing structure includes a first matching portion, the first matching portion is sealingly matched with the front outer edge of the pivot portion, and the first matching portion is located between a pair of side walls of the base.

[0011] In a further specific embodiment of the present invention, the sealing structure further comprises a second matching portion, the second matching portion is sealingly matched with the outer edge of the rear side of the pivoting portion, and the second matching portion is located on the contact support.

[0012] In a further specific embodiment of the present invention, the sealing structure further comprises a second mating portion, the second mating portion sealingly mating with the rear outer edge of the pivot portion, the second mating portion being arranged on the contact cover, and the second mating portion being located between a pair of side walls of the base.

[0013] In yet another specific embodiment of the present invention, the contact support further comprises a mating cavity, the mating cavity is used to match the outer shape of the contact cover on the side close to the contact support, and a fixed mounting portion is further provided on the side of the contact cover close to the contact support; a fixing hole and a boss are further provided on the mating cavity, the fixing hole corresponds to the mounting hole on the fixed mounting portion; the boss is embedded in the contact cover.

[0014] In yet another specific embodiment of the present invention, the contact cover has a pair of hook grooves on both sides of the raised portion, the pair of hook grooves are located below both sides of the raised portion, and the extended sides of the gas producing part fall into the hook grooves on both sides of the raised portion.

[0015] In a further specific embodiment of the present invention, a step surface is provided on the inner side of the gas generating member and on the contact portions on both sides of the protrusion.

[0016] The present invention has the beneficial effect of adopting the above structure: the sealing structure inside the contact cover prevents arc gas from flowing through the inside of the contact cover and contacting the conductor below, thereby preventing breakdown. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the arc extinguishing chamber of the present invention; Figure 2 It is a structural schematic diagram of the moving contact of the present invention; Figure 3 It is a structural schematic diagram of the static contact of the present invention; Figure 4 A three-dimensional schematic diagram of the contact cover of the present invention; Figure 5 It is a front schematic diagram of the contact cover of the present invention; Figure 6 A side sectional view of the contact cover of the present invention; Figure 7 It is a schematic diagram of the structure of the contact cover and the first moving contact piece according to the present invention; Figure 8 This is a schematic diagram of the structure of the contact support of the present invention; Fig. 9 It is a schematic diagram of the structure of the contact cover and the arc extinguishing chamber according to the present invention.

[0018] In the figure: 1. moving contact, 11. moving contact piece, 111. first moving contact piece, 1111. moving arc contact, 1112. pivoting part, 1113. pivoting hole, 112. second moving contact piece, 1121. moving main contact, 12. contact cover, 121. base, 122. raised part, 1221. opening, 1222. baffle part, 123. hook groove part, 124. fixed installation part, 1241. installation hole, 125. first matching part, 13. contact support, 131. Second matching part, 132. Partition wall, 133. Matching cavity, 1331. Fixing hole, 1332. Boss, 134. Slot, 14. Side plate, 15. Outgoing busbar, 16. Contact spring; 2. Static contact, 21. Conductive block, 211. Opening slot, 212. Notch, 213. Abutting slot, 22. Static main contact, 23. Static arc contact, 24. Arc striking piece; 3. Arc extinguishing chamber, 31. Gas producing part, 311. Step surface; 100. Make way for slot. DETAILED DESCRIPTION

[0019] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but the description of the embodiments is not a limitation of the technical solution. Any changes in form rather than substance based on the concept of the present invention should be regarded as the protection scope of the present invention.

[0020] In the following description, all concepts related to directionality or orientation such as up, down, left, right, front and back are based on the positions shown in the corresponding drawings. They are only used to facilitate the description of the technical solution provided by the present invention and simplify the description in conjunction with the drawings, and therefore cannot be understood as a special limitation on the technical solution provided by the present invention.

[0021] like Figure 1 The contact arc extinguishing device of the switch includes a moving contact 1, a stationary contact 2 and an arc extinguishing chamber 3, wherein the moving contact 1 and the stationary contact 2 form a contact system, and the arc extinguishing chamber 3 is located above the contact system. When the switch is disconnected, an arc is generated on the moving contact 1 and the stationary contact 2 when they are separated, and the arc enters the arc extinguishing chamber 3 and is extinguished in the arc extinguishing chamber 3.

[0022] As the name implies, the moving contact 1 is rotatably arranged, while the stationary contact 2 is fixedly arranged. The moving contact 1 rotates to close or separate from the stationary contact 2, thereby realizing the closing or opening action of the switch.

[0023] Specifically, the switch further comprises a shell, an inner cavity is formed inside the shell, the moving contact 1 and the static contact 2 are located in the inner cavity, and the inner cavity is open upward, and the arc extinguishing chamber 3 is installed at the upper opening.

[0024] like Figure 2 Combination Figure 8 , is a schematic diagram of a moving contact 1. The moving contact 1 comprises a moving contact piece 11, a contact cover 12, a contact support 13, a side plate 14 and an outgoing busbar 15. The moving contact piece 11 is rotatably arranged between a pair of side plates 14 through a rotating shaft, and the rotating shaft passes through the moving contact piece 11 and the contact cover 12 at the same time, and a pair of side plates 14 are fixedly installed on both sides of the contact support 13. The above-mentioned installation relationship makes the moving contact piece 11 and the contact support 13 a rotationally arranged installation relationship. The outgoing busbar 15 is located on one side of the rotation center of the moving contact 1, and the contact support 13 is also located on one side of the rotation center in another direction. The outgoing busbar 15 is fixed on the housing of the switch. The moving contact piece 11 rotates with the contact support 13, but the moving contact piece 11 itself can also rotate relative to the contact support 13. The moving contact piece 11 and the outgoing busbar 15 are electrically connected through a soft connection (not shown).

[0025] The movable contact piece 11 described above includes a first movable contact piece 111 and a second movable contact piece 112. The first movable contact piece 111 has a greater extension length relative to the second movable contact piece 112. When the movable contact head 1 and the arc extinguishing chamber 3 are both installed in place, the head of the first movable contact piece 111 extends into the interior of the arc extinguishing chamber 3, while the second movable contact piece 112 is located outside the arc extinguishing chamber 3.

[0026] The first movable contact piece 111 is provided with a movable arc contact point 1111, and the second movable contact piece 112 is provided with a movable main contact point 1121. The movable arc contact point 1111 follows the head of the first movable contact piece 111 and is located inside the arc extinguishing chamber 3, while the movable main contact point 1121 follows the second movable contact piece 112 and is located outside the arc extinguishing chamber 3. The head of the first movable contact piece 111 and the grid pieces inside the arc extinguishing chamber 3 are arranged to extend past each other.

[0027] The contact cover 12 is fixed on the contact support 13, and the contact cover 12 is sleeved on the first movable contact piece 111. It can also be understood that the contact cover 12 only corresponds to the first movable contact piece 111. The first movable contact piece 111 extends upward through the interior of the contact cover 12. In this embodiment, two first movable contact pieces 111 form a group and are centered, while the second movable contact pieces 112 are divided into two sides and are respectively located on the left and right sides of a group of first movable contact pieces 111. The two side walls of the contact cover 12 separate the first movable contact piece 111 from the second movable contact piece 112 within the range of the side walls.

[0028] As Figure 3 , it is a schematic diagram of the static contact 2. The static contact 2 includes a conductive block 21. On the side of the conductive block 21 close to the movable contact head 1, a static main contact point 22 and a static arc contact point 23 are installed. The static arc contact point 23 is located between a pair of static main contact points 22, and the three contact points are arranged in a "pin" shape. The static main contact point 22 is used to cooperate with the movable main contact point 1121 correspondingly, and the static arc contact point 23 is used to cooperate with the movable arc contact point 1111 correspondingly. On the side of the conductive block 21 close to the arc extinguishing chamber 3, an arc guiding piece 24 is installed, and the arc guiding piece 24 extends towards the arc extinguishing chamber 3.

[0029] A pair of opening slots 211 are provided on the conductive block 21. The pair of opening slots 211 are opened from the top of the conductive block 21 and extend downward, and the lower end of the opening slot 211 is a closed end. The opening slot 211 separates the static arc contact 23 from the conductive block 21 on both sides. When the moving contact 1 and the static contact 2 are separated to generate an arc, the current on the static contact 2 side needs to bypass the opening slot 211 and reach the static arc contact 23 from below. The electromotive repulsion generated by the current path is more conducive to the upward movement of the arc.

[0030] A notch 212 is provided at the lower side of the conductive block 21, and the notch 212 clears the contact cover 12. Since the contact cover 12 is mounted on the contact support 13 and extends in the direction of the stationary contact 2, the notch 212 and the corresponding clearing slot 100 on the housing together clear the position space of the contact cover 12 during the operation of the moving contact 1, and does not affect the rotation or swing of the contact cover 12.

[0031] A pair of abutment grooves 213 are provided on the conductive block 21 at the inner sides of the pair of opening grooves 211 . The pair of abutment grooves 213 are located at the two outer sides of the static arc contact 23 and are used for abutting and cooperating with the arc extinguishing chamber 3 .

[0032] like Figure 4 , Figure 5 , Figure 6 Schematic diagram of the contact cover 12. The contact cover 12 is made of insulating material, preferably a thermosetting material, such as DMC or BMC.

[0033] The contact cover 12 includes a base 121, a raised portion 122 is provided above the base 121, that is, in the direction toward the arc extinguishing chamber 3, and hook grooves 123 are provided on both sides of the raised portion 122. The hook grooves 123 are a pair, respectively located on both sides of the raised portion 122. Preferably, the hook grooves 123 are located below both sides of the raised portion 122.

[0034] A fixing and mounting portion 124 is also provided on a side of the contact cover 12 close to the contact support 13. The contact cover 12 is mounted on the contact support 13, specifically on a side surface of the contact support 13 close to the static contact 2, through the fixing and mounting portion 124. More preferably, a mounting hole 1241 is provided on the fixing and mounting portion 124, a screw presses the fixing and mounting portion 124, and the screw head penetrates through the mounting hole 1241 and is inserted into the contact support 13, so as to achieve the fixing and mounting of the contact cover 12 and the contact support 13.

[0035] The ridge 122 has an opening 1221 on one side corresponding to the first movable contact piece 111, and has baffles 1222 extending upward on both sides of the opening 1221. The opening 1221 is used to accommodate the first movable contact piece 111, and the baffles 1222 correspond to both sides of the first movable contact piece 111. In this embodiment, there are two first movable contact pieces 111. At this time, the two first movable contact pieces 111 form a group and are located in the opening 1221, and a pair of baffles 1222 are located on both sides of the group of first movable contact pieces 111.

[0036] Since the contact cover 12 is made of insulating material, preferably thermosetting material or thermoplastic material, the interior is hollow, which is easy to manufacture. On this basis, the base 121 is a shell structure with a hollow interior. A first matching portion 125 is provided between a pair of side walls of the base 121. The first matching portion 125 is located between a pair of side walls of the base 121 in the form of a rib, and the first matching portion 125 matches the first moving contact piece 111. The base 121 has a rotating hole for the rotating shaft of the moving contact piece 11 to pass through.

[0037] like Figure 7 , which is a side cross-sectional view of the moving contact 1. The first moving contact piece 111 includes a moving arc contact 1111 installed on the rotating end. The first moving contact piece 111 also includes a pivoting portion 1112 and a pivoting hole 1113. The pivoting portion 1112 is located around the pivoting hole 1113 and surrounds the pivoting hole 1113 in the form of a cofferdam. Combined with the structural form of the long sheet body of the first moving contact piece 111, the pivoting portion 1112 has an arc-shaped outer edge on the side close to the stationary contact 2 and the side away from the stationary contact 2, that is, the front and rear faces of the first moving contact piece 111.

[0038] As can be seen from the figure, the moving contact 1 also includes a contact spring 16, which is inserted into the spring cavity in the contact support 13, and one end of the contact spring 16 abuts against the contact support 13, and the other end abuts against the first moving contact piece 111. Of course, since the second moving contact piece 112 is not shown in the figure, it also has the contact spring 16 to cooperate with it, so as to provide contact pressure for the second moving contact piece 112.

[0039] Combination Figure 8The contact support 13 includes a second matching portion 131, and the second matching portion 131 is sealed with the outer edge of the rear side of the pivoting portion 1112, and the first matching portion 125 on the contact cover 12 is sealed with the outer edge of the front side of the pivoting portion 1112. In terms of direction, the front side refers to the side close to the static contact 2, and the rear side refers to the side away from the static contact 2. In the invention, the sealing match means that the outer shape of the first matching portion 125 and the second matching portion 131 matches the outer edge of the pivoting portion 1112 in shape, and the above-mentioned sealing match ensures that the matching two sides are in conflict or have a small gap match. In this way, the gas is blocked, and the gas is blocked from continuing to move downward through the sealing match of the two places, preventing the arc gas from contacting the conductor below through the sealing match of the two places, such as a conductive soft connection. The second matching portion 131 can also be arranged on the contact cover 12, and preferably, the second matching portion 131 is located between a pair of side walls of the base 121. A better matching effect can be achieved. The first matching portion 125 and the second matching portion 131 are both located inside the contact cover 12 .

[0040] The contact support 13 also includes a partition wall 132, a matching cavity 133, and a slot 134. When the moving contact 1 is installed, the partition wall 132 is inserted between the moving contact pieces 11. In this embodiment, the first moving contact piece 111 is composed of two pieces. Similarly, the second moving contact piece 112 is also separated by the partition wall 132 every two pieces. The matching cavity 133 is used to match the shape of the contact cover 12 close to the contact support 13 to ensure the positioning effect of the two during installation. A fixing hole 1331 and a boss 1332 are also provided on the matching cavity 133. The fixing hole 1331 corresponds to the mounting hole 1241 on the fixed mounting portion 124, which is convenient for screw fixing. The boss 1332 is embedded in the contact cover 12 to facilitate the installation and positioning of the contact cover 12 and the contact support 13.

[0041] The slots 134 are a pair and are arranged at intervals. The slots 134 extend downward from the rotating end of the contact support 13. When the moving contact 1 is installed, the first moving contact piece 111 is located between the pair of slots 134, and the second moving contact piece 112 is located on the left and right outer sides of the pair of slots 134.

[0042] like Fig. 9, the arc extinguishing chamber 3 includes a grid (not shown) installed inside, and the grid has a pair of grid legs extending downward on both sides. The gas-producing member 31 is also a pair, and the pair of gas-producing members 31 are arranged between the pair of grid legs, and the pair of gas-producing members 31 are arranged at intervals, and an arc channel or a narrow gap is formed therebetween. The head of the first moving contact piece 111 protrudes through the grid legs in the height direction. The pair of gas-producing members 31 extend downward, that is, extend toward the contact system, and the side of the gas-producing member 31 close to the moving contact 1 is inserted into the slot 134, and during the entire movement process of the moving contact 1, the insertion and matching of the gas-producing member 31 and the slot 134 are established without separation. On the side of the gas-producing member 31 close to the static contact 2, the gas-producing member 31 abuts against the abutment groove 213 on the conductive block 21. The gas-generating part 31 corresponds to the part of the contact cover 12, and extends downward from both sides of the protrusion 122, so that the cooperation between the gas-generating part 31 and the protrusion 122 can better block the arc gas from moving downward. The extended side of the gas-generating part 31 falls into the hook groove 123 on both sides of the protrusion 122. More preferably, in order to further improve the gas sealing effect between the gas-generating part 13 and the protrusion 122, a step surface 311 is provided on the inner side of the gas-generating part 31 and the contact part on both sides of the protrusion 122. This matching structure has a better gas blocking effect.

Claims

1. A contact arc extinguishing device for a switch, comprising a moving contact (1), a stationary contact (2) and an arc extinguishing chamber (3), wherein the moving contact (1) comprises a moving contact piece (11), a contact cover (12) and a contact support (13), wherein the moving contact piece (11) is rotatably arranged on the contact support (13), the contact cover (12) is fixedly mounted on the contact support (13), and the moving contact piece (11) comprises a first moving contact piece (111); characterized in that: The first movable contact piece (111) penetrates through the interior of the contact cover (12) and extends upward, the first movable contact piece (111) has a pivot hole (1113) and a pivot portion (1112) located around the pivot hole (1113), and the inner side of the contact cover (12) has a sealing structure that cooperates with the outer edge of the pivot portion (1112).

2. A contact arc extinguishing device for a switch according to claim 1, characterized in that: The sealing structure comprises a first matching portion (125), and the first matching portion (125) is sealingly matched with the front outer edge of the pivoting portion (1112).

3. The contact arc extinguishing device of a switch according to claim 2, characterized in that: The sealing structure further comprises a second matching portion (131), and the second matching portion (131) is sealingly matched with the outer edge of the rear side of the pivoting portion (1112).

4. The contact arc extinguishing device of a switch according to claim 1, characterized in that: The arc extinguishing chamber (3) comprises a pair of gas producing parts (31), an arc channel is formed between the pair of gas producing parts (31), and the movable contact piece (11) further comprises a second movable contact piece (112); the first movable contact piece (111) extends into the interior of the arc channel, and the second movable contact piece (112) is located outside the contact cover (12) and outside the arc channel.

5. The contact arc extinguishing device of a switch according to claim 4, characterized in that: The contact cover (12) has a raised portion (122) extending toward the arc extinguishing chamber (3), and a pair of gas generating parts (31) extend downward and isolate a first moving contact piece (111) located on the inner side of the raised portion (122) from a second moving contact piece (112) located on the outer side of the raised portion (122).

6. A contact arc extinguishing device for a switch according to claim 5, characterized in that: The contact cover (12) also includes a base (121), the raised portion (122) extends from the base (121) toward the arc extinguishing chamber (3), the base (121) is an internally hollow shell structure, and the sealing structure includes a first matching portion (125), the first matching portion (125) is sealed with the front outer edge of the pivot portion (1112), and the first matching portion (125) is located between a pair of side walls of the base (121).

7. A contact arc extinguishing device for a switch according to claim 6, characterized in that: The sealing structure further comprises a second matching portion (131), wherein the second matching portion (131) is sealingly matched with the outer edge of the rear side of the pivot portion (1112), and the second matching portion (131) is located on the contact support (13).

8. The contact arc extinguishing device of a switch according to claim 6, characterized in that: The sealing structure also includes a second matching portion (131), which is sealingly matched with the outer edge of the rear side of the pivot portion (1112), and the second matching portion (131) is arranged on the contact cover (12), and the second matching portion (131) is located between a pair of side walls of the base (121).

9. The contact arc extinguishing device of a switch according to claim 1, characterized in that: The contact support (13) also includes a matching cavity (133), and the matching cavity (133) is used to match the shape of the contact cover (12) on the side close to the contact support (13), and a fixed mounting portion (124) is also provided on the side of the contact cover (12) close to the contact support (13); a fixing hole (1331) and a boss (1332) are also provided on the matching cavity (133), and the fixing hole (1331) corresponds to the mounting hole (1241) on the fixed mounting portion (124); the boss (1332) is embedded in the contact cover (12).

10. The contact arc extinguishing device of a switch according to claim 5, characterized in that: The contact cover (12) has a pair of hook grooves (123) on both sides of the raised portion (122), and the pair of hook grooves (123) are located below the two sides of the raised portion (122), and the extended sides of the gas generating part (31) fall into the hook grooves (123) on both sides of the raised portion (122).

11. A contact arc extinguishing device for a switch according to claim 10, characterized in that: A step surface (311) is provided on the inner side of the gas generating member (31) and at the contact portions on both sides of the raised portion (122).

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