A multi-contact structure for an electricity meter with a built-in load switch

Abstract

The utility model relates to a multi-contact structure with an internal load switch for an electric energy meter, which at least includes multiple groups of contact structures. Each group of contact structures includes a moving contact and a static contact arranged opposite to each other. The moving contacts in multiple groups of contact structures are located in the same row, and the static contacts in multiple groups of contact structures are located in the same row. When the contact structure is in the off state, the gap S1 between at least one group of moving contact and static contact is smaller than the gap S2 between the moving contact and static contact of the remaining groups, that is, S1 < S2; This structure is a double-contact or multi-contact parallel structure. When the contact is in the open state, through structural design, the distances between the corresponding moving contact and static contact are set differently, with a height difference. The contact with a smaller distance is used as the arcing contact, and the contact with a larger distance is used as the current-carrying contact, so as to achieve the effect of protecting the carrying contact, that is, no arc burns the surface of the contact.

Description

Technical Field

[0001] This utility model relates to the field of load switch technology, and in particular to a multi-contact structure for a built-in load switch for an electricity meter. Background Technology

[0002] As an electronic control device, the load switch controls a large current with a small current, and is widely used in automatic control circuits, playing roles such as automatic adjustment, safety protection, and circuit switching. A key characteristic of load switches is that their contacts maintain an open or closed state. When load switches are used in AC (sine wave) circuits, zero-crossing switching technology can be employed, resulting in relatively lower requirements for arc-extinguishing capability. However, when used in DC circuits, if the load switch is subjected to a short-circuit current or struck by lightning, and the contacts open, the arc in existing load switch products can easily strike the plastic parts of the base or outer casing. This can cause the base or push-pull mechanism to melt, resulting in low arc resistance and serious damage to the load switch structure, leading to unnecessary losses. Therefore, improving the arc-extinguishing capability of load switches to better suit high DC current and high DC voltage applications has been a long-standing technological pursuit in the industry, especially when load switches are subjected to large DC loads. Utility Model Content

[0003] The purpose of this utility model is to overcome the defects in the existing technology and provide a multi-contact structure for a built-in load switch in an energy meter.

[0004] To achieve the above objectives, the technical solution of this utility model is to design a multi-contact structure for a built-in load switch in an energy meter, comprising at least multiple sets of contact structures. Each set of contact structures includes a moving contact and a stationary contact arranged in opposite directions. The moving contacts in the multiple sets of contact structures are located in the same row, and the stationary contacts in the multiple sets of contact structures are located in the same row. When the contact structure is in the open state, the gap S1 between at least one set of moving and stationary contacts is smaller than the gap S2 between the moving and stationary contacts in the remaining sets, i.e., S1 <S2。

[0005] In a further preferred embodiment, each of the moving contacts is pivotally connected to the mounting base via a moving contact plate.

[0006] In a further preferred embodiment, the mounting base is provided with multiple abutment portions that protrude along the direction of contact or separation between the moving contact and the stationary contact, and abut against the corresponding moving contact plate.

[0007] In a further preferred embodiment, along the direction in which the moving contact and the stationary contact come into contact or separate, at least one abutment protrudes by a greater distance than the other abutments.

[0008] In a further preferred embodiment, the movable contact plate has a semi-circular rotating part on one side of the middle position, the mounting base has a pair of coaxial pivot shafts in the middle, a pair of first arc-shaped plates are provided on the outer periphery of the pivot shafts, and a pair of second arc-shaped plates are provided on the opposite side of the pair of first arc-shaped plates, which are separated from the pivot shafts.

[0009] A further preferred technical solution is that a protective plate is provided on the mounting base between the abutting post and the first arc-shaped plate, and a first contact plate is also provided on one side of the mounting base. A partition is provided between the first contact plate and the protective plate to form two protective cavities. The end of the movable contact plate near the movable contact point is located in the corresponding protective cavity. A connecting plate extending outward from the pivot axis is provided at the end of the mounting base away from the movable contact point. An arc-shaped second contact plate is provided at the outer extension end of the connecting plate.

[0010] In a further preferred embodiment, the movable contact plate is provided with a magnetic suction element near the movable contact point.

[0011] In a further preferred embodiment, the movable contact plate is provided with a first spring sheet near the movable contact point, and the first spring sheet is connected to the movable contact point and the magnetic attractor respectively.

[0012] In a further preferred embodiment, the end of the movable contact plate away from the movable contact point is provided with a second spring sheet, one end of which abuts against the movable contact plate.

[0013] The advantages and beneficial effects of this utility model are as follows: This structure is a dual-contact or multi-contact parallel structure. When the contacts are in the open state, the structural design sets different distances between the contacts corresponding to the moving contact bridge and the contacts on the stationary plate assembly, resulting in a height difference. The contacts with smaller distances serve as arc-ignition contacts, and the contacts with larger distances serve as current-carrying contacts. Therefore, there is a sequence when the contacts make or break. Because the current-carrying contacts have larger distances, their actual travel is shorter than that of the arc-ignition contacts, and they will open before the arc-ignition contacts. Since the arc-ignition contacts remain closed when the current-carrying contacts break (the circuit is still open), no arc will be generated when the current-carrying contacts break. When the arc-ignition contacts continue to separate, an arc will be generated, so they can serve as arc-ignition contacts to protect the current-carrying contacts, i.e., to prevent arc damage to the contact surface.

[0014] Similarly, when the contacts are closed, the arcing contact contacts the corresponding stationary contact before the current-carrying contact. Although the contacts bounce when they make contact, and an arc burns the contact surface during the bounce, the bounce is very short and ends before the current-carrying contact makes contact. Therefore, the circuit is closed before the current-carrying contact makes contact, and even if the current-carrying contact bounces when it makes contact, no arc will burn the contact surface.

[0015] The contact resistance of a load switch is strongly related to the surface condition of the contacts. A complete contact surface will greatly increase the contact resistance. When two or more contacts are connected in parallel, the contact resistance of the current-carrying contacts is smaller because the surface of the current-carrying contacts is more complete. According to the characteristics of parallel circuits, the parallel resistance will be less than the minimum resistance in the circuit. Therefore, under this condition, the stability and reliability of the contact resistance are guaranteed. Attached Figure Description

[0016] Figure 1 This is a top view of the present invention;

[0017] Figure 2 This is an isometric drawing of the present invention;

[0018] Figure 3 This is a schematic diagram of the misalignment of the moving contact in this utility model;

[0019] Figure 4 This is one of the isometric drawings of the mounting base and moving contact plate assembly of this utility model;

[0020] Figure 5 This is the second isometric drawing of the mounting base and moving contact plate assembly of this utility model;

[0021] Figure 6 This is one of the exploded isometric views of the mounting base and moving contact plate of this utility model;

[0022] Figure 7 This is the second exploded isometric view of the mounting base and moving contact plate of this utility model;

[0023] Figure 8 This is an isometric schematic diagram of another embodiment of the present invention;

[0024] Figure 9 This utility model Figure 8 Top view;

[0025] In the diagram: 10, moving contact; 20, stationary contact; 30, moving contact plate; 31, semi-circular rotating part; 40, second lead-out piece; 50, first lead-out piece; 60, magnetic suction piece; 70, first spring piece; 80, mounting base; 81, abutment post; 82, guard plate; 83, first arc-shaped plate; 84, pivot shaft; 85, connecting plate; 86, second contact plate; 87, second arc-shaped plate; 88, first contact plate; 89, partition plate; 90, second spring piece; 110, first moving spring piece; 120, second moving spring piece. Detailed Implementation

[0026] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0027] Since it is necessary to ensure that the contact resistance during the operation of the load switch is in a relatively small state, when the contact surface is damaged by the arc and the stability of the contact resistance cannot be effectively guaranteed, it is necessary to consider how to prevent the contacts from being damaged and reduce the influence of the arc during the operation. Therefore, the distances between different moving contacts 20 and the static contacts 10 are different. That is, when the contact system is in the off state, the gap S1 between a set of moving contact 20 and the static contact 10 is smaller than the gap S2 between another set of static contact 10 and the moving contact 20, i.e., S1 < S2. The contacts with a smaller distance are used as arcing contacts, and the contacts with a larger distance are used as current-carrying contacts. With this structure, the switch can normally carry current. When the current is interrupted, the arc generated only affects one set of contacts, which can ensure the surface integrity of the other set of contacts. In this way, the contact resistance of the load switch can be kept in a relatively small and stable state.

[0028] The contact gap can be realized by various structures. In one embodiment, as Figure 8 and Figure 9 shown, the contact system adopts a double-contact structure, and moreover, the two moving contacts and the two static contacts are arranged facing each other.

[0029] Specifically, the contact system includes a first lead piece 50, a first moving spring piece 110, a second lead piece 40, a second moving spring piece 120, an arcing-end contact group, and a current-carrying-end contact group. Each of the arcing-end contact group and the current-carrying-end contact group includes at least one pair of moving contacts and static contacts. In this embodiment, the arcing-end contact group includes a first moving contact 21 and a first static contact 11, and the current-carrying-end contact group includes a second static contact 12 and a second moving contact 22. As Figure 5 shown, when the contact system is in the off state, the gap S1 between the first moving contact 21 and the first static contact 11 is smaller than the gap S2 between the second static contact 12 and the second moving contact 22, i.e., S1 < S2.

[0030] In the contact system of this embodiment, the first moving spring piece 110 and the second moving spring piece 120 are connected to the first lead piece 50. The first moving contact 21 is arranged at the end of the first moving spring piece 110 far from the first lead piece 50; the second moving contact 22 is arranged at the end of the second moving spring piece 110 far from the first lead piece 50. The first static contact 11 and the second static contact 12 are connected to the second lead piece 40, and the first static contact 11 is arranged facing the first moving contact 21, and the second moving contact 22 and the second static contact 12 are arranged facing each other.

[0031] It is understood that in the contact system of this embodiment of the invention, because the contact gaps between the two sets of moving and stationary contacts are different in the open state, during the process of switching the contact system from the closed state to the open state, the second stationary contact 12 and the second moving contact 22 with a larger contact gap will disconnect first, before the first moving contact 21 and the first stationary contact 11 with a smaller contact gap. Furthermore, when the second stationary contact 12 and the second moving contact 22 with a larger contact gap just disconnects, the first moving contact 21 and the first stationary contact 11 with a smaller contact gap have not yet completely disconnected. Therefore, the second stationary contact 12 and the second moving contact 22 with a larger contact gap will not generate an electric arc when disconnected. Thus, the second stationary contact 12 and the second moving contact 22 with a larger contact gap function as current carriers, while the first moving contact 21 and the first stationary contact 11 with a smaller contact gap function as arc ignition points.

[0032] It should be added that the different contact gaps between the two sets of moving and stationary contact groups can be achieved by reducing the contact height. Specifically, for example... Figure 7 and 8 As shown, the contact thickness of the second stationary contact 12 and the second moving contact 22 is less than the contact thickness of the first moving contact 21 and the first stationary contact 11. Therefore, when the contact system is in the open state, since the contact thickness of the second stationary contact 12 and the second moving contact 22 is smaller than the contact thickness of the first moving contact 21 and the first stationary contact 11, the contact gap between the second stationary contact 12 and the second moving contact 22 is larger and greater than the contact gap between the first moving contact 21 and the first stationary contact 11.

[0033] Furthermore, the contact gaps between the two sets of moving and stationary contact groups are designed to be different, which can also be achieved by tilting at least one of the first moving spring 110 or the second moving spring 120.

[0034] In the contact system, the first moving spring 110 and the second moving spring 120 are arranged side by side. The moving and stationary contacts on the first moving spring 110 and the second moving spring 120 correspond to each other to form two sets of moving and stationary contact groups. This allows the two sets of moving and stationary contact groups, namely the first moving contact 21 and the first stationary contact 11, and the second stationary contact 12 and the second moving contact 22, to form a parallel circuit structure after contact. The contact system is designed as a short-circuit resistant structure with a double-contact parallel circuit, which effectively reduces temperature rise and improves the ability to carry large currents such as short-circuit current or lightning strike current.

[0035] Of course, the contact gap can also adopt other structures, such as in some embodiments. Figure 1-7As shown, for example, in a multi-contact structure, multiple moving contacts are arranged in a row, and multiple stationary contacts are arranged in a row on the opposite side of the multiple moving contacts, such that the multiple moving contacts and the multiple stationary contacts face each other. When the contact system is in the open state, the gap S1 between at least one set of moving contacts 20 and stationary contacts 10 is smaller than the gap S2 between the remaining sets of moving contacts 20 and stationary contacts 10, that is, S1 <S2,

[0036] Specifically, each of the moving contacts 20 is fixedly connected to one of the moving contact plates 30, and the two moving contact plates 30 are pivotally connected in the mounting base 80. The two moving contact plates 30 rotate independently around the pivot center in the mounting base 80.

[0037] The mounting base 80 has two abutment posts 81 at one end near the moving contact 20. The two abutment posts 81 are centered on different positions on the mounting base 80. The two abutment posts 81 have a preset distance along the direction from the moving contact to the stationary contact for contact or separation. After the two moving contact plates 30 are assembled on the mounting base 80, the end of the moving contact plate 30 near the moving contact 20 abuts against the abutment post 81, and the distance between the two moving contacts 20 and the corresponding stationary contacts 10 is different. The contact with the smaller distance serves as the arcing contact, and the contact with the larger distance serves as the current carrying contact. This structure ensures that when the relay is carrying current normally, the arc generated when the current is interrupted only affects one set of contacts, ensuring the surface integrity of the other set of contacts. This ensures that the contact resistance of the relay is in a low and stable state.

[0038] like Figure 4-7 As shown, in order to enable quick assembly and disassembly of the moving contact plate 30 and to allow the moving contact 20 and the stationary contact 10 to have different distances and rotate independently, the moving contact plate 30 is provided with a semi-circular arc rotating part 31 on one side of the middle position. The mounting base 80 has a pair of coaxial pivot shafts 84 in the middle. A pair of first arc-shaped plates 83 are provided on the outer periphery of the pivot shafts 84 and are fitted with the pivot shafts 84. A pair of second arc-shaped plates 87 are provided on the opposite side of the pair of first arc-shaped plates 83 and are separated from the pivot shafts 84. The semi-circular arc rotating part 31 is rotatably installed between the pivot shafts 84 and the second arc-shaped plates 87.

[0039] A protective plate 82 is provided on the mounting base 80 between the abutment post 81 and the first arc-shaped plate 83. A first contact plate 88 is also provided on one side of the mounting base 80. A partition 89 is provided between the first contact plate 88 and the protective plate 82 to form two protective cavities. The end of the movable contact plate 30 near the movable contact 20 is located in the corresponding protective cavity. A connecting plate 85 extending outward from the pivot shaft 84 is provided at the end of the mounting base 80 away from the movable contact 20. An arc-shaped second contact plate 86 is provided at the outer extension end of the connecting plate 85.

[0040] like Figure 1-3 As shown, a magnetic attractor 60 is provided on the moving contact plate 30 near the moving contact 20. The magnetic attractor 60 has a U-shaped structure and is mounted on the moving contact plate 30. A magnetic attractor 60 is also provided on the second lead plate 40 near the stationary contact 10. The magnetic attractor 60 is made of a high magnetic permeability material. When the moving and stationary contacts are closed, current enters the moving contact plate 30 from the first lead plate 50. After being energized, the moving contact plate 30 magnetizes the magnetic attractor 60 on the moving contact plate 30. The magnetic attractor 60 is magnetic and attracts each other with the magnetic attractor 60 on the first lead plate 50 to ensure that the moving contact 20 and the stationary contact 10 fit more tightly.

[0041] like Figure 2-3 As shown, the movable contact plate 30 is also provided with a first spring piece 70 near the movable contact 20. The first spring piece 70 is connected to the movable contact 20 and the magnetic attractor 60 respectively. The first spring piece 70 is made of elastic material and serves as an energy storage element. The first spring piece 70 is hook-shaped and located in the first contact plate 88 of the mounting base 80. When the armature assembly drives the movable contact plate 30 to rotate, the movable contact 20 is disconnected from the stationary contact 10. After the permanent magnet in the armature assembly 90 attracts the yoke of the electromagnetic coil assembly to complete self-locking, the first spring piece 70 deforms and completes energy storage. When a drive signal is provided to the electromagnetic coil assembly, the armature assembly starts to rotate in the opposite direction. The first spring piece 70 returns to its original shape and assists in pushing the movable contact plate 30 to rotate in the opposite direction. The movable contact 20 and the stationary contact 10 are attracted together, improving the sensitivity of the movable contact plate 30.

[0042] like Figure 2-3 As shown, the moving contact plate 30 is further provided with a second spring piece 90 at the end away from the moving contact 20. One end of the second spring piece 90 abuts against the moving contact plate 30, and the other end abuts against the inner side of the switch housing near the first lead-out piece 50. The second spring piece 90 is made of elastic material and serves as an energy storage element. The second spring piece 90 is hook-shaped. When the armature assembly drives the moving contact plate 30 to rotate, the moving contact 20 is disconnected from the stationary contact 10. After the permanent magnet in the armature assembly attracts the yoke of the electromagnetic coil assembly to complete self-locking, the second spring piece 90 deforms and completes energy storage. When a drive signal is provided to the electromagnetic coil assembly, the armature assembly begins to rotate in the opposite direction, and the second spring piece 90 returns to its original shape, which will help push the moving contact plate 30 to rotate in the opposite direction. The moving contact 20 and the stationary contact 10 are attracted together, improving the sensitivity of the moving contact plate 30.

[0043] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A multi-contact structure for a built-in load switch in an electricity meter, comprising at least multiple sets of contact structures, characterized in that, Each group of contact structures includes one moving contact and one stationary contact arranged in opposite directions. The moving contacts in multiple groups of contact structures are located in the same row, and the stationary contacts in multiple groups of contact structures are located in the same row. When the contact structure is in the open state, the gap S1 between at least one group of moving and stationary contacts is smaller than the gap S2 between the moving and stationary contacts in the remaining groups, i.e., S1 <S2。 2. The multi-contact structure for a built-in load switch in an energy meter according to claim 1, characterized in that, Each of the moving contacts is pivotally connected to the mounting base via a moving contact plate.

3. The multi-contact structure for a built-in load switch in an energy meter according to claim 2, characterized in that, The mounting base has multiple abutment portions that protrude along the direction of contact or separation between the moving contact and the stationary contact, and abut against the corresponding moving contact plate.

4. The multi-contact structure for a built-in load switch in an energy meter according to claim 3, characterized in that, Along the direction in which the moving contact and the stationary contact come into contact or separate, at least one abutment protrudes by a greater distance than the other abutments.

5. A multi-contact structure for a built-in load switch in an energy meter according to claim 3 or 4, characterized in that, The movable contact plate has a semi-circular rotating part on one side of the middle position. The mounting base has a pair of coaxial pivot shafts in the middle. A pair of first arc-shaped plates are provided on the outer periphery of the pivot shafts. A pair of second arc-shaped plates are provided on the opposite side of the pair of first arc-shaped plates, which are separated from the pivot shafts.

6. The multi-contact structure for a built-in load switch in an energy meter according to claim 5, characterized in that, A protective plate is provided on the mounting base between the abutting part and the first arc-shaped plate. A first contact plate is also provided on one side of the mounting base. A partition is provided between the first contact plate and the protective plate to form two protective cavities. The end of the movable contact plate near the movable contact point is located in the corresponding protective cavity. A connecting plate extending outward from the pivot axis is provided at the end of the mounting base away from the movable contact point. An arc-shaped second contact plate is provided at the outer extension end of the connecting plate.

7. The multi-contact structure for a built-in load switch in an energy meter according to claim 2, characterized in that, The movable contact plate is provided with a magnetic suction element near the movable contact point.

8. The multi-contact structure for a built-in load switch in an energy meter according to claim 7, characterized in that, The movable contact plate is also provided with a first spring piece near the movable contact point, and the first spring piece is connected to the movable contact point and the magnetic attractor respectively.

9. A multi-contact structure for a built-in load switch in an energy meter according to claim 7 or 8, characterized in that, The movable contact plate is further provided with a second spring at one end away from the movable contact point, and one end of the second spring abuts against the movable contact plate.

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