An explosion-proof magnetic latching relay

Abstract

The utility model discloses a kind of explosion-proof magnetic latching relays, relate to relay technical field.The core is in adopting η shape dynamic spring piece structure: one end riveting dynamic lead-out piece, the other end riveting dynamic contact and pressure spring piece.Through the current positive and negative layout of η shape dynamic spring piece, the Lorentz force generated by large current is mutually cancelled, and contact repulsion explosion is inhibited;η shape structure is simultaneously used to extend arm, and the operating force is reduced by the gap design between cooperation piece, to realize ≥5.5mm electrical clearance when dynamic and static contact is disconnected.The structure solves the problem of insufficient opening distance (only 0.8mm) of conventional relay, meets the explosion-proof requirement of national net intelligent electric meter.

Description

Technical Field

[0001] This utility model belongs to the field of relay technology, specifically relating to an explosion-proof magnetic latching relay. Background Technology

[0002] As the core load switch of a single-phase smart energy meter, the performance of the magnetic latching relay directly affects the safety and reliability of the meter. Currently, the State Grid Corporation of China has set forth clear requirements for magnetic latching relays used in single-phase smart energy meters: when the relay is disconnected, an electrical clearance of at least 5.5mm must be maintained between the moving and stationary contacts to meet explosion-proof safety standards.

[0003] However, conventional magnetic latching relays have a significant drawback: their contact gap is typically only about 0.8 mm, far below the 5.5 mm required by the State Grid. This deficiency leads to two major problems: Insufficient explosion-proof capability: When a short circuit fault occurs in the circuit, the electromagnetic force generated by the large current can easily cause the contacts with a small opening distance to close again, causing arcing or even an explosion. Reliability risks: Insufficiently small opening gaps make it difficult to effectively isolate high voltages, posing a risk of breakdown and failing to meet the safety requirements of smart meters for load switches.

[0004] In existing technologies, the contact system structure of traditional magnetic latching relays (such as a single straight spring design) is limited by mechanical space and material rigidity, making it difficult to achieve a large opening distance of 5.5mm without significantly increasing the relay size. Furthermore, the Lorentz force generated when a large current passes through the contacts further exacerbates the risk of contact adhesion, hindering improvements in explosion-proof performance. Utility Model Content

[0005] The purpose of this utility model embodiment is to provide an explosion-proof magnetic latching relay, which utilizes the symmetrical current path of the η-type moving spring: when a large short-circuit current flows through the moving spring, the opposite currents generate mutually repulsive Lorentz forces; the repulsive force is transmitted to the riveting point of the moving lead, and is converted into a reverse resisting force; after superimposed on the push plate pressure, an upward resultant force is formed, which directly cancels the downward repulsive force on the moving contact, thereby effectively resisting the impact of a 10kA-level short-circuit current, preventing the contact from melting or bursting, and thus solving at least one of the technical problems involved in the background art.

[0006] To solve the above-mentioned technical problems, this utility model is implemented as follows: This utility model embodiment provides an explosion-proof magnetic latching relay, including a base, a magnetic circuit assembly, an armature assembly, a stationary lead-out piece assembly, a moving lead-out piece assembly, a push piece, and a fixing frame; The movable lead-out piece assembly includes a movable lead-out piece, an n-shaped movable spring, a movable contact, and a pressure spring; one end of the n-shaped movable spring is riveted to the movable lead-out piece, and the other end is riveted to the movable contact and the pressure spring. The stationary lead-out piece assembly includes a stationary lead-out piece and a stationary contact riveted thereon; The pusher is sleeved on the η-type moving spring, and one end of it is limited to the limiting groove of the pressure spring. The armature assembly is connected to the other end of the push plate via a long plastic handle; When the armature assembly rotates, it drives the push plate to drive the η-type moving spring to close or open the moving contact with the stationary contact. When the contact is open, the contact gap is ≥5.5mm.

[0007] Optionally, the pressure spring is provided with two limiting grooves, which are inserted into the limiting grooves during the assembly of the push plate to achieve limiting.

[0008] Optionally, the η-type moving spring is composed of four independent springs with gaps between adjacent springs, and the ends of the springs that are riveted to the moving contact are stacked, and the ends of the springs that are riveted to the moving lead-out piece are stacked.

[0009] Optionally, when a large current flows through the contact system, the forward and reverse currents of the η-type moving spring generate Lorentz forces in opposite directions, and a resisting force is generated at the riveting point between the moving lead and the η-type moving spring. This resisting force, together with the push plate pressure, counteracts the repulsive force on the moving contact.

[0010] Optionally, the moving lead-out piece, the stationary lead-out piece, and the pressing block are fixed to the base with adhesive, and the pressing block presses the moving lead-out piece tightly.

[0011] Optionally, the point of force of the η-type moving spring extends to the bend of the spring, thereby reducing the pulling force required to disconnect the contact by extending the lever arm.

[0012] Optionally, the length of the plastic handle of the armature assembly is designed such that when the armature assembly rotates to its maximum angle, it causes the moving contact and the stationary contact to form an electrical gap of 5.5mm.

[0013] Optionally, it may also include a top cover that cooperates with the base to form a storage space.

[0014] Compared with the prior art, the advantages of this utility model are as follows: (1) This utility model, through its innovative η-type moving spring structure (one to four-piece design of the moving spring), allows the point of force to extend to the η-type bend when the armature drives the push plate to move, significantly increasing the lever arm. Compared with traditional single-piece springs or bundled springs, this design greatly reduces the operating force required to open the contacts (by about 70%), reliably achieving a contact opening distance of ≥5.5mm, meeting the mandatory safety standards of State Grid smart meters for load switches.

[0015] (2) This utility model utilizes the symmetrical current path of the η-type moving spring: when a large short-circuit current flows through the moving spring, the current segments in the same direction generate mutually repulsive Lorentz forces (F12, F21); the repulsive force F12 is transmitted to the riveting point of the moving lead-out piece, and is converted into a reverse resisting force F11, and F11=F12; after the pusher pressure F is superimposed, an upward resultant force (F21+F11+F) is formed, which directly cancels the downward repulsive force F34 on the moving contact, thereby effectively resisting the impact of a 10kA-level short-circuit current and preventing the contact from melting or bursting.

[0016] (3) The η-type moving spring of this utility model has a reserved gap in the middle so that the four springs can deform independently and not squeeze each other, thus avoiding stress concentration; when the contact is closed, the pressure spring provides constant micro pressure to ensure stable contact resistance.

[0017] (4) The design of the dynamic / static lead-out piece assembly, push piece limiting groove (hook groove), and pressing block glue fixation of this utility model simplifies the assembly process and reduces the sensitivity of production tolerance. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein: Figure 1 A schematic diagram of the overall structure of the explosion-proof magnetic latching relay provided by this utility model; Figure 2 A top view of the explosion-proof magnetic latching relay provided by this utility model after removing the outer casing; Figure 3 A three-dimensional structural diagram of the explosion-proof magnetic latching relay provided by this utility model after removing the outer shell; Figure 4 The explosion-proof schematic diagram of the explosion-proof magnetic latching relay provided by this utility model. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0020] The terms "first," "second," etc., used in the specification and claims of this utility model 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 this utility model 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, the 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.

[0021] Please see Figures 1 to 3 As shown, this utility model embodiment provides an explosion-proof magnetic latching relay, including a base 100, a magnetic circuit assembly 200, an armature assembly 300, a stationary lead-out piece assembly 400, a moving lead-out piece assembly 500, a pusher piece 7, a fixing frame 600, and a top cover 700.

[0022] The movable lead-out piece assembly 500 includes a movable lead-out piece 1, an n-type movable spring piece 2, a movable contact 3, and a pressure spring piece 4.

[0023] One end of the η-type moving spring 2 is riveted to the moving lead-out piece 1, and the other end is riveted to the moving contact 3 and the pressure spring 4. Specifically, in conjunction with... Figure 4 As shown, the η-type moving spring 2 includes a first straight section 21 extending horizontally from one end riveted to the moving contact 3, a second straight section 22 bent in the opposite direction from the end of the first straight section 21 away from the moving contact 3 and spaced parallel to the first straight section 21, and a vertical section 23 extending vertically from the second straight section 22 away from the first straight section 21. The length of the second straight section 22 is shorter than that of the first straight section 21. In this way, an η-type moving spring can be formed.

[0024] In one specific embodiment, the η-type moving spring 2 is composed of four independent springs with a gap 10 between adjacent springs. The ends of the springs that are riveted to the moving contact 3 are stacked, and the ends of the springs that are riveted to the moving lead-out piece 1 are stacked. By reserving a gap 10 in the middle of the η-type moving spring 2, the four springs can deform independently and do not squeeze each other, thus avoiding stress concentration. When the contact is closed, the pressure spring provides a constant micro pressure to ensure stable contact resistance.

[0025] The point of force of the η-type moving spring 2 extends to the bend 12 of the spring, and the pulling force required to disconnect the contact is reduced by extending the lever arm.

[0026] Through an innovative η-type moving spring structure (with one to four separate moving spring pieces), the point of force can extend to the η-shaped bend 12 when the armature drives the push plate, significantly increasing the lever arm. Compared to traditional single-piece or bundled springs, this design greatly reduces the operating force required to open the contacts (by approximately 70%), reliably achieving a contact opening distance of ≥5.5mm, meeting the mandatory safety standards for load switches in State Grid smart meters.

[0027] The stationary lead-out piece assembly 400 includes a stationary lead-out piece 5 and a stationary contact 6 riveted thereon.

[0028] The push plate 7 is sleeved on the η-type moving spring 2, and one end of it is limited within the limiting groove 8 of the pressure spring 4. Specifically, the pressure spring 4 is provided with two limiting grooves 8, and the push plate 7 is sleeved into the limiting groove 8 during assembly to achieve limiting.

[0029] The armature assembly 300 is connected to the other end of the push plate 7 via a plastic long handle 9. When the armature assembly 300 rotates, it drives the push plate 7 to drive the η-type moving spring 2 to close or open the moving contact 3 and the stationary contact 6. When open, the contact gap is ≥5.5mm.

[0030] Combined Figure 4 As shown, when a large current flows through the contact system, the forward and reverse currents of the η-type moving spring 2 generate Lorentz forces (F12, F21) that are opposite in direction and equal in magnitude. The riveting joint between the moving lead 1 and the η-type moving spring 2 generates a resisting force F11, and F11=F12, thereby offsetting the Lorentz force F12. The Lorentz force F21, together with the pusher pressure F, offsets the repulsive force F34 on the moving contact 3, thus effectively resisting the impact of a 10kA short-circuit current and preventing the contacts from melting or bursting.

[0031] The moving lead-out piece 1, the stationary lead-out piece 5, and the pressing block 11 are fixed to the base 100 with adhesive. The pressing block 11 presses the moving lead-out piece 1, which simplifies the assembly process and reduces the sensitivity to production tolerances.

[0032] The length of the plastic handle 9 of the armature assembly 300 is designed such that when the armature assembly 300 rotates to its maximum angle, it causes the moving contact 3 to form an electrical gap of 5.5mm with the stationary contact 6.

[0033] The upper cover 700 and the base 100 cooperate to form a storage space to store the magnetic circuit assembly 200, armature assembly 300, etc.

[0034] 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.

[0035] Furthermore, it should be noted that the scope of the methods and systems in the embodiments of this utility model is not limited to performing functions in the order shown or discussed. It 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. Additionally, features described with reference to certain examples may be combined in other examples.

[0036] 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. An explosion-proof magnetic latching relay, comprising a base (100), a magnetic circuit assembly (200), an armature assembly (300), a stationary lead assembly (400), a moving lead assembly (500), a pusher (7), and a fixing frame (600); characterized in that: The moving lead-out piece assembly (500) includes a moving lead-out piece (1), an n-type moving spring (2), a moving contact (3), and a pressure spring (4); one end of the n-type moving spring (2) is riveted to the moving lead-out piece (1), and the other end is riveted to the moving contact (3) and the pressure spring (4). The stationary lead-out piece assembly (400) includes a stationary lead-out piece (5) and a stationary contact (6) riveted thereon. The push plate (7) is sleeved on the n-type moving spring (2), and one end of it is limited to the limiting groove (8) of the pressure spring (4); The armature assembly (300) is connected to the other end of the push plate (7) via a plastic handle (9); When the armature assembly (300) rotates, it drives the push plate (7) to drive the η-type moving spring (2) to close or open the moving contact (3) and the stationary contact (6). When the contact is open, the contact gap is ≥5.5mm.

2. The relay according to claim 1, characterized in that: The pressure spring (4) is provided with two limiting grooves (8). When the pusher (7) is assembled, it is fitted into the limiting grooves (8) to achieve the limiting.

3. The relay according to claim 1, characterized in that: The η-type moving spring (2) is composed of four independent springs with gaps (10) between adjacent springs. The ends of the springs that are riveted to the moving contact (3) are stacked, and the ends of the springs that are riveted to the moving lead-out piece (1) are stacked.

4. The relay according to claim 1, characterized in that: When a large current flows through the contact system, the positive and negative currents of the η-type moving spring (2) generate Lorentz forces in opposite directions. The riveting joint between the moving lead (1) and the η-type moving spring (2) generates a resisting force, which, together with the push plate pressure, cancels out the repulsive force on the moving contact (3).

5. The relay according to claim 1, characterized in that: The moving lead-out piece (1), the stationary lead-out piece (5), and the pressing block (11) are fixed in the base (100) by adhesive, and the pressing block (11) presses the moving lead-out piece (1).

6. The relay according to claim 3, characterized in that: The point of force of the η-type moving spring (2) extends to the bend of the spring (12), and the pulling force required to disconnect the contact is reduced by extending the lever arm.

7. The relay according to claim 1, characterized in that: The length of the plastic handle (9) of the armature assembly (300) is designed such that when the armature assembly (300) rotates to the maximum angle, it causes the moving contact (3) to form an electrical gap of 5.5 mm with the stationary contact (6).

8. The relay according to claim 1, characterized in that: It also includes a top cover (700) that cooperates with the base (100) to form a storage space.

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