Parallel contact system for magnetic latching relay and magnetic latching relay

Abstract

The invention discloses a parallel contact system for a magnetic latching relay and the magnetic latching relay, and belongs to the technical field of electrical switches. The contact system comprises a base and a pair of contact assemblies arranged in parallel, and each contact assembly comprises a zigzag structure formed by a bus bar, a movable contact spring assembly and a static contact. The two movable contact spring assemblies are parallel and electrically connected in parallel. The relay comprises the contact system, a coil assembly, a magnetic steel assembly and a push rod. According to the invention, through parallel connection of the double zigzag structures, current shunting and contact resistance reduction are realized, electromagnetic attraction and repulsive force between the parallel conductors and between the conductors and the bus bars are utilized, the current-carrying capability, large current impact resistance and reliability of the relay are significantly improved, and the size of a product is reduced.

Description

Technical Field

[0001] This invention relates to the field of electrical switch technology, and more particularly to an improved structure of a relay contact system, especially a parallel contact system for a magnetic latching relay and a magnetic latching relay including the system. Background Technology

[0002] Magnetic latching relays are widely used in smart meters, new energy fields, and other areas due to their low power consumption and stable state. In these applications, relays often need to withstand large load currents and short-term surges of high current (such as short-circuit currents). Therefore, improving the load-carrying capacity, surge resistance, and reducing the operating temperature rise of relays are key areas of current technological development.

[0003] In existing technologies, one solution to improve resistance to high current surges is to use a single zigzag busbar and moving spring assembly. When a large current flows through, the electrodynamic force (Lorentz force) generated at the corner of the zigzag structure helps to press the moving and stationary contacts together more tightly, preventing them from separating. However, this solution has relatively high contact resistance and a high temperature rise, and to meet the high current carrying capacity requirements, the moving spring often needs to be widened, resulting in an increase in the overall thickness of the relay.

[0004] Another option is to use a simple parallel structure of moving reeds, which can achieve current shunting, but has limited effect on improving resistance to electrodynamic shocks.

[0005] Therefore, there is an urgent need for a new type of contact system structure that can comprehensively improve the current carrying capacity, shock resistance, and heat dissipation performance of relays without significantly increasing the product size. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a parallel contact system and a magnetic latching relay for use in magnetic latching relays. This structure can effectively improve the product's load-bearing capacity and resistance to high current surges, while reducing circuit contact resistance and temperature rise.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A parallel contact system for a magnetic latching relay includes a base and a pair of contact assemblies mounted on the base in parallel. The pair of contact assemblies includes a first zigzag busbar assembly and a second zigzag busbar assembly; each zigzag busbar assembly includes a busbar, a moving spring assembly connected to one end of the busbar, and a stationary contact connected to the same end of the busbar; the moving spring assembly of the first zigzag busbar assembly and the moving spring assembly of the second zigzag busbar assembly are parallel to each other and electrically connected in parallel.

[0008] A magnetic latching relay includes a coil assembly, a magnet assembly, a push rod driven by the magnet assembly, and the aforementioned parallel contact system for the magnetic latching relay; the magnet assembly includes a left arm and a right arm, and the push rod includes a first push rod and a second push rod respectively connected to the left arm and the right arm.

[0009] Compared with the prior art, the present invention has the following significant advantages: (1) Improve load capacity: By using two sets of zigzag busbar assemblies in parallel, the current is naturally shunted in the two sets of moving spring assemblies when it flows through, so that the entire contact system can withstand a larger load current and improve the load capacity of the product.

[0010] (2) Enhanced resistance to high current impact: After the double zigzag structure is connected in parallel, the current path forms multiple parallel conductors. According to the principle that "currents in the same direction attract each other and currents in opposite directions repel each other" between parallel conductors (i.e., Ampere's law, the magnitude of which is directly proportional to the product of the currents and inversely proportional to the distance between them), electric attraction and electric repulsion forces will be generated simultaneously between the moving reed assemblies and between the moving reed assemblies and their respective busbars. The combined effect of these forces can effectively suppress the negative impact of the huge electrodynamic force generated when a large current (such as a short-circuit current of 4.5kA or above) passes through on the contact pressure, significantly reduce the vibration of the moving reed assembly, and ensure that the moving and stationary contacts can still reliably contact under the impact of high current, greatly improving the impact resistance and reliability of the product.

[0011] (3) Reduced contact resistance and temperature rise: The contact resistance between the moving and stationary contacts is effectively halved due to the parallel connection of the two paths, thereby significantly reducing the total resistance of the entire contact circuit. According to Joule's law (Q=I²Rt), the heat generated is reduced under the same load current, and the operating temperature rise of the product is effectively reduced, improving the stability and lifespan of long-term operation.

[0012] (4) Optimize product size: Compared with the traditional solution of widening the moving spring to achieve the same current carrying capacity, the present invention can control the width of a single moving spring while meeting the high current carrying capacity requirements through parallel current splitting, which helps to reduce the overall thickness of the relay and realize the miniaturization of the product. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein: Figure 1 This is a schematic diagram of the overall assembly of the relay contact system in Embodiment 1 of the present invention (with the tail end riveted).

[0014] Figure 2 for Figure 1 A schematic diagram of two sets of zigzag busbar components connected in parallel.

[0015] Figure 3 A schematic diagram of the structure of a single zigzag busbar assembly.

[0016] Figure 4 This is a schematic diagram of a moving reed assembly.

[0017] Figure 5 This is a schematic diagram of the first type of zigzag busbar assembly.

[0018] Figure 6 This is a schematic diagram of the second type of zigzag busbar assembly.

[0019] Figure 7 This is a schematic diagram of the third type of zigzag busbar assembly.

[0020] Figure 8 This is a schematic diagram of the fourth type of zigzag busbar assembly.

[0021] Figure 9 This is a schematic diagram of the fifth type of zigzag busbar assembly.

[0022] Figure 10 This is a schematic diagram of the magnet assembly.

[0023] Figure 11 This is a schematic diagram of the first push rod.

[0024] Figure 12 This is a schematic diagram of the second push rod.

[0025] Figure 13 This is a schematic diagram illustrating the current path and force analysis of the contact system after it is energized.

[0026] Figure 14 This is a schematic diagram of the overall structure of a magnetic latching relay.

[0027] Figure 15 This is a schematic diagram of the overall assembly of the relay contact system in Embodiment 2 of the present invention (the tail is riveted).

[0028] Figure 16 for Figure 15 A schematic diagram of two sets of zigzag busbar components connected in parallel.

[0029] Figure 17 This is a schematic diagram of another type of zigzag busbar assembly (with the tail section riveted).

[0030] Figure 18This is a schematic diagram of another type of moving spring assembly.

[0031] The following are the labels in the diagram: 1. First zigzag busbar assembly; 1-1. Moving spring assembly; 1-1-1. Moving contact; 1-2. Stationary contact; 1-3. Busbar; 2. Base; 3. First push rod; 4. Magnet assembly; 4-1. Left arm of magnet assembly; 4-2. Right arm of magnet assembly; 5. Fixing frame; 6. Coil assembly; 7. Second zigzag busbar assembly; 8. Second push rod; 9. Top cover. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] The terms "first," "second," etc., used in the specification and claims of this invention are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0034] Example 1 like Figure 1 , Figure 2 and Figure 14 As shown, this embodiment provides a magnetic latching relay, the core of which lies in the adoption of a novel parallel contact system.

[0035] The parallel contact system includes a base 2 made of insulating material and a pair of contact assemblies arranged in parallel on the base 2. Specifically, the pair of contact assemblies are a first zigzag busbar assembly 1 and a second zigzag busbar assembly 7.

[0036] like Figure 3As shown, each zigzag busbar assembly (taking assembly 1 as an example) includes a busbar 1-3 that is approximately L-shaped or has a bend. One end of the busbar 1-3 is fixed with a stationary contact 1-2 by riveting or welding. The same end of the busbar 1-3 is connected to a moving spring assembly 1-1 by riveting or welding. The end of the moving spring assembly 1-1 is provided with a moving contact 1-1-1. The stationary contact 1-2, the busbar 1-3, and the moving spring assembly 1-1 together form a zigzag conductive path with a current bend. The moving spring assembly of the first zigzag busbar assembly 1 and the moving spring assembly of the second zigzag busbar assembly 7 are arranged parallel in space, and their electrical input and output ends are connected in parallel to form an electrical parallel relationship. This parallel connection constitutes a dual current path, realizing automatic current shunting, thereby directly improving the current carrying capacity of the entire contact system.

[0037] The specific form of the moving reed assembly 1-1 can vary. For example... Figure 4 As shown, it can be composed of one or more elastic metal sheets, on which one (as shown), two, or more moving contacts can be set. When two moving contacts are set, a slot (not shown) can be opened in the middle of the moving spring to partially separate the two contact areas, thereby enhancing the independence of contact operation. The moving spring assembly can also adopt the following... Figure 18 Other structures shown.

[0038] The shape of the zigzag busbar assembly can also vary in several ways. Figures 5 to 9 Five different designs were demonstrated, all of which can achieve a basic zigzag current path. Specifically, Figure 5 It adopts double moving contacts, and the two moving contacts are not separated by slots. The moving spring assembly, stationary contact, and busbar are riveted or welded as a whole. Figure 6 A single-acting contact is used, and the moving spring assembly, stationary contact, and busbar are riveted or welded together as a whole. Figure 7 It adopts double moving contacts, and the two moving contacts are separated by slots. The moving spring assembly, stationary contact, and busbar are riveted or welded as a whole. Figure 8 It adopts double moving contacts, and the two moving contacts are not separated by slots. The moving spring assembly and the busbar, and the stationary contact and the busbar are riveted or welded respectively. Figure 9 A single-acting contact is used, and the moving spring assembly and the busbar, as well as the stationary contact and the busbar, are riveted or welded respectively.

[0039] like Figure 1 , Figure 2As shown, in a preferred embodiment of this example, the first zigzag busbar assembly 1 and the second zigzag busbar assembly 7 are "integral riveted" at their tails (i.e., the ends furthest from the contacts) through a common riveting point, thereby achieving mechanical fixation and electrical parallel connection. This integral riveting method has a compact structure and reliable connection. The integral riveting ensures the stability and low resistance of the parallel connection, further guaranteeing the reliability of current shunting.

[0040] The magnetic latching relay further includes a coil assembly 6, a magnet assembly 4, a first push rod 3, and a second push rod 8. The magnet assembly 4 is rotatably mounted and includes a left arm 4-1 and a right arm 4-2 (e.g., ...). Figure 10 One end of the first push rod 3 is hinged to the left arm 4-1 of the magnet assembly, and the other end acts on the moving spring assembly of the first busbar assembly 1; one end of the second push rod 8 is hinged to the right arm 4-2 of the magnet assembly, and the other end acts on the moving spring assembly of the second busbar assembly 7 (e.g., Figure 11 , Figure 12 The coil assembly 6, magnet assembly 4, and contact system are typically mounted on the mounting bracket 5 and covered by the cover 9, forming a complete relay (e.g., Figure 14 ).

[0041] Its working principle is as follows: When a control pulse current of a certain direction is applied to the coil assembly 6, it drives the magnet assembly 4 to rotate to a stable position. The left arm 4-1 and right arm 4-2 of the magnet assembly respectively drive the first push rod 3 and the second push rod 8, which in turn pushes the two sets of moving spring assemblies 1-1, ensuring reliable contact between the moving contact 1-1-1 and the stationary contact 1-2, thus achieving closing. After closing, the magnet assembly 4 remains in this position under the action of permanent magnet force, without the need for continuous coil energization. When opening is required, a reverse pulse current is applied to the coil assembly 6.

[0042] The key innovations and beneficial effects of this invention are manifested in the working process: like Figure 13 As shown, when the load current (or large inrush current) I flows into the parallel contact system, the current is split into I1 and I2, which flow through the first component 1 and the second component 7, respectively.

[0043] Current shunting and current carrying: Since it is a parallel circuit, the total current I = I1 + I2. This reduces the current carried by each path, thereby increasing the overall current carrying capacity of the system.

[0044] Electromagnetic force generation and shock resistance mechanism: Analyzing the path of the first component 1, current I1 flows in from busbar 1-3, and after passing the corner, flows into its moving spring assembly 1-1. At this time, in the section near the corner of the zigzag structure, the current in the moving spring of the first component 1 (I1 pointing downwards) and the current in the moving spring of the second component 7 (I2 pointing downwards) are parallel currents in the same direction. According to Ampere's law, currents in the same direction attract each other, generating an attractive force F. 吸 This force helps to bring the two moving spring assemblies closer together, thereby indirectly increasing the pressure on their respective contacts.

[0045] Meanwhile, the current (I1) in the moving reed of the first component 1 is parallel to the current in the adjacent section of its own busbar 1-3 (I1 is horizontal to the right). According to Ampere's law, opposite currents repel each other, generating a repulsive force F. 斥 This repulsive force acts on the moving spring assembly, and its direction is such that it tends to rotate around the fulcrum (such as the riveting point). This tendency also increases the pressure between the moving and stationary contacts when the circuit is closed.

[0046] Therefore, when a large current passes through, the moving reed assembly is simultaneously subjected to the electric attraction from its parallel partner and the electric repulsion from its own busbar. The combined effect of these forces greatly counteracts the destructive electrodynamic force that could separate the contacts, significantly suppresses the moving reed jitter, and ensures the contact reliability of the contacts under the impact of large current.

[0047] Reducing resistance and temperature rise: From a circuit perspective, the contact resistance R between the two moving and stationary contacts... contact They are connected in parallel. The total contact resistance R after parallel connection total = (R contact The efficiency is 1 / 2, which is half that of a single-path method. According to the heating formula Q = I² R total With the total current I and time t being the same, halving the resistance means a significant reduction in heat generation Q, thereby effectively reducing the temperature rise of the relay during operation.

[0048] Example 2 like Figure 15 , Figure 16 As shown, the main difference between this embodiment and Embodiment 1 lies in the parallel connection method of the zigzag busbar assembly.

[0049] In this embodiment, the tails of the first zigzag busbar assembly 1 and the second zigzag busbar assembly 7 are not riveted together as a whole, but are "riveted separately" at different positions on the base 2 or the conductive bracket, and then electrically connected in parallel through additional conductive connecting pieces (not shown in the figure) or directly on the circuit board. Figure 17A zigzag busbar assembly structure suitable for this approach is demonstrated.

[0050] This "separate riveting at the tail" method (benefits: provides greater flexibility in the internal layout and wiring of the relay, making it easier to adapt to different installation spaces and circuit designs).

[0051] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0052] Furthermore, it should be noted that the scope of the methods and systems in the embodiments of the present invention is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

[0053] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of the present invention.

Claims

1. A parallel contact system for a magnetic latching relay, comprising a base (2) and a pair of parallel contact assemblies mounted on the base, characterized in that: The pair of contact components includes a first zigzag busbar assembly (1) and a second zigzag busbar assembly (7); Each zigzag busbar assembly includes a busbar (1-3), a moving spring assembly (1-1) connected to one end of the busbar, and a stationary contact (1-2) connected to the same end of the busbar. The moving spring assembly of the first zigzag busbar assembly (1) and the moving spring assembly of the second zigzag busbar assembly (7) are parallel to each other and electrically connected in parallel.

2. The parallel contact system for a magnetic latching relay according to claim 1, characterized in that, The moving reed assembly (1-1) includes one or more moving reeds, and the moving reeds have one, two or more moving contacts (1-1-1).

3. The parallel contact system for a magnetic latching relay according to claim 2, characterized in that, When the moving spring assembly (1-1) is provided with two moving contacts (1-1-1), the moving spring that carries the moving contacts has a slot between the two moving contacts.

4. The parallel contact system for a magnetic latching relay according to claim 1, characterized in that, The moving spring assembly (1-1), the stationary contact (1-2), and the busbar (1-3) are riveted or welded to form a zigzag structure.

5. The parallel contact system for a magnetic latching relay according to claim 4, characterized in that, The tails of the first zigzag busbar assembly (1) and the second zigzag busbar assembly (7) are connected in parallel by integral riveting or separate riveting.

6. The parallel contact system for a magnetic latching relay according to claim 1, characterized in that, The shape of the "Z"-shaped structure is configured such that when current flows through, a current in the same direction is formed in one section between the parallel moving reed assemblies, and a current in the opposite direction is formed in one section between the moving reed assembly and the corresponding busbar.

7. A magnetic latching relay, comprising a coil assembly (6), a magnet assembly (4), a push rod driven by said magnet assembly, and a parallel contact system for a magnetic latching relay as claimed in any one of claims 1 to 6; The magnet assembly (4) includes a left arm (4-1) and a right arm (4-2), and the push rod includes a first push rod (3) and a second push rod (8) respectively connected to the left arm and the right arm.

8. The magnetic latching relay according to claim 7, characterized in that, It also includes a mounting bracket (5) and a top cover (9) for housing the coil assembly (6), the magnet assembly (4) and the contact system.

9. The magnetic latching relay according to claim 7, characterized in that, The relay is configured to withstand short-term high current surges of not less than 4.5kA.

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