Contact modules for relays and relays

Abstract

This application relates to a contact module for a relay and a relay. The relay includes a contact module comprising an insulating cover, a stationary contact, and an insulating ring. The insulating cover forms a receiving cavity with an opening at one end. An isolation post is provided on the cavity wall at the end of the receiving cavity away from the opening. A through hole is formed at the end of the insulating cover away from the opening, penetrating the isolation post and communicating with the receiving cavity. The stationary contact passes through the through hole, with one end exposed outside the insulating cover and the other end passing through the through hole and extending into the receiving cavity. The insulating ring is disposed inside the receiving cavity and coaxially fitted around at least the portion of the stationary contact extending into the receiving cavity. This allows the insulating ring to be fitted around the portion of the stationary contact exposed outside the isolation post when the length specifications of the stationary contact are different, thus completely enclosing the stationary contact together with the isolation post to prevent splashed metal particles from contaminating the insulating cover. This eliminates the need for re-die-casting the insulating cover, thereby significantly reducing the manufacturing cost of the relay.

Description

Technical Field

[0001] This application relates to the field of electronic control device technology, and in particular to a contact module for a relay and a relay. Background Technology

[0002] A relay is an electronic control device that essentially acts as an "automatic switch" by using a smaller current to control a larger current. Therefore, it plays a role in automatic adjustment, safety protection, and circuit switching in circuits, and is widely used in fields such as new energy vehicles. High-voltage DC relays are a type of relay. Most existing high-voltage DC relays adopt a direct-acting structure with a moving spring, utilizing the cooperation of two stationary contacts and one moving spring. Depending on the actual application in the vehicle, the contacts need to connect, disconnect, and switch under load to achieve the "switching" function.

[0003] When a relay operates, especially during circuit disconnection, the current between the contacts is suddenly interrupted, generating an electric arc. Therefore, an insulating cover is necessary to isolate the arc generated during operation from the external environment and to suppress its generation and spread, ensuring safe circuit operation. However, during this process, the internal contacts are easily eroded by the arc, producing flying metal particles. To prevent the inner wall of the insulating cover from being contaminated by these particles and causing an insulation short circuit, the insulating cover usually contains insulating pillars to enclose the internal contacts and prevent metal particle splashing. However, since insulating covers are typically die-cast, if the length and dimensions of the internal contacts are different, the insulating cover must be re-die-cast to completely enclose the internal contacts, significantly increasing production costs. Utility Model Content

[0004] Therefore, it is necessary to address the problem that when the length specifications of the internal contacts of existing relays are different, the insulating cover must be re-die-cast to completely enclose the internal contacts, which greatly increases the production cost. To solve the above-mentioned problems, an arc-extinguishing structure for relays and a relay including the arc-extinguishing structure are provided.

[0005] According to one aspect of this application, a contact module for a relay is provided, comprising:

[0006] An insulating cover, the insulating cover forming a receiving cavity with an opening at one end, the receiving cavity having an isolation post on the cavity wall at the end away from the opening, and the insulating cover having a through hole at the end away from the opening that penetrates the isolation post and communicates with the receiving cavity;

[0007] A stationary contact is inserted through the through hole, with one end of the stationary contact exposed outside the insulating cover, and the other end of the stationary contact passing through the through hole and extending into the receiving cavity;

[0008] An insulating ring is disposed within the receiving cavity and coaxially sleeved on at least the portion of the stationary contact that extends into the receiving cavity.

[0009] In one embodiment, the stationary contact includes a connecting post and a contact block. The connecting post passes through the through hole and extends into the receiving cavity. The contact block is connected to one end of the connecting post extending into the receiving cavity. An insulating ring is sleeved on the portion of the connecting post extending into the receiving cavity, and one end of the insulating ring abuts against the contact block along its own axial direction, while the other end abuts against the isolating post.

[0010] In one embodiment, the contact block includes a first contact portion and two second contact portions symmetrically arranged with the central axis of the through hole as the axis of symmetry. One side of the second contact portion abuts against the insulating ring, and the other side is used to contact the moving contact piece.

[0011] In one embodiment, a limiting groove is formed on one side of each of the two second contact portions, the maximum distance between the two limiting grooves is equal to the diameter of the insulating ring, and the groove width of each limiting groove is equal to the ring diameter of the insulating ring, so that the insulating ring is confined in the limiting groove.

[0012] In one embodiment, the contact block and the connecting post are separate structures.

[0013] In one embodiment, a creepage groove is formed on one side of the insulating ring around its central axis. The creepage groove is configured to form at least two creepage gates on the insulating ring. All the creepage gates are arranged around the central axis of the insulating ring and are radially spaced along the insulating ring.

[0014] In one embodiment, the dimensions of each creepage gate in its own axial direction gradually increase or decrease along the radial direction of the insulating ring and away from the central axis of the insulating ring.

[0015] In one embodiment, the dimensions of each creepage gate in its own axial direction gradually increase or decrease along the radial direction of the insulating ring and away from the central axis of the insulating ring.

[0016] In one embodiment, the insulating ring is made of ceramic.

[0017] According to another aspect of this application, a relay is provided, comprising:

[0018] The contact module as described in any of the above solutions;

[0019] A movable contact piece, which is movably disposed within the receiving cavity of the insulating cover;

[0020] An electromagnetic drive module is used to drive the moving contact to move between a closed position where it is in electrical contact with the stationary contact and an open position where it is separated from the stationary contact.

[0021] The aforementioned contact module for a relay and the relay including the contact module, by providing an insulating ring coaxially sleeved within the receiving cavity of the insulating cover at least the portion of the stationary contact exposed above the isolation post, allows for complete encapsulation of the stationary contact together with the isolation post during relay manufacturing when the length specifications of the stationary contact are different. This prevents splashed metal particles from contaminating the insulating cover, eliminating the need for re-die-casting of the insulating cover and thus significantly reducing the relay manufacturing cost. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the appearance of a relay provided in one embodiment of this application.

[0023] Figure 2 This is an exploded view of the contact module in a relay provided in an embodiment of this application.

[0024] Figure 3 Cross-sectional view of the contact module in a relay provided in an embodiment of this application Figure 1 .

[0025] Figure 4 Cross-sectional view of the contact module in a relay provided in an embodiment of this application Figure 2 .

[0026] Figure 5 for Figure 4 An enlarged schematic diagram of region A in the middle.

[0027] Figure 6 This is a schematic diagram of the structure of the contact block in a contact module provided in an embodiment of this application.

[0028] Explanation of reference numerals in the attached figures:

[0029] 10. Relay; 100. Housing; 200. Contact module; 210. Stationary contact; 211. Connecting post; 2111. Connecting part; 2112. Protrusion part; 212. Contact block; 2121. First contact part; 2122. Second contact part; 2122a. Limiting groove; 220. Insulating cover; 221. Receiving cavity; 222. Isolating post; 223. Through hole; 230. Insulating ring; 231. Creepage groove; 232. Creepage grid. Detailed Implementation

[0030] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0031] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0032] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0033] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0034] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0035] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0036] This application provides a contact module for a relay and a relay including the contact module. The relay is used in an automatic control circuit and plays a role in automatic adjustment, safety protection, and circuit switching. For example, it can be used to connect the load power supply and the load, control the on / off of the circuit between the load power supply and the load, thereby playing a role in protecting the load through circuit switching and automatic adjustment, and preventing the load from being damaged by excessive current.

[0037] The following description uses a high-voltage DC relay used in an electric vehicle charging station as an example to illustrate the structure of the relay provided in this application. It is understood that the relay provided in this application can be any type of relay used in other fields, and is not limited to a high-voltage DC relay used in electric vehicle charging stations; there are no particular limitations in this regard.

[0038] The following description uses a high-voltage DC relay used in an electric vehicle charging station as an example to illustrate the structure of the relay and its contact module provided in this application. It is understood that the relay provided in this application can be any type of relay used in other fields, and is not limited to a high-voltage DC relay used in electric vehicle charging stations; there are no particular limitations in this regard.

[0039] See Figure 1 and Figure 2 , Figure 1A schematic diagram of the appearance of a relay 10 according to an embodiment of this application is shown. The relay 10 provided in one embodiment of this application includes a housing 100, a contact module 200, a moving contact, and an electromagnetic drive module. The contact module 200, the moving contact, and the electromagnetic drive module are all disposed within the housing 100. The contact module 200 has a stationary contact 210. In the embodiment shown, there are two stationary contacts 210, one for connecting to the load power supply and the other for connecting to the load (e.g., an automobile). The electromagnetic drive module is connected to the moving contact and drives the moving contact to move relative to the stationary contact 210, enabling it to contact or disengage from the stationary contact 210, thereby controlling the on / off state of the load power supply and the load circuit.

[0040] Specifically, the electromagnetic drive module includes a push rod, a moving iron core, and an energized coil. The lower end of the push rod is connected to the moving iron core, and the upper end of the push rod is connected to the moving contact piece. When the coil is energized, the coil generates a magnetic field, and the moving iron core is driven by the magnetic force in the magnetic field to move vertically. This allows the push rod to drive the moving contact piece to abut against or detach from the stationary contact 210, thereby realizing the switching on and off of the circuit.

[0041] For contact module 200, such as Figure 2 and Figure 3 As shown, the contact module 200 includes not only the stationary contact 210 but also an insulating cover 220. The insulating cover 220 is provided because when the relay 10 operates, especially during circuit disconnection, the current between the contacts is suddenly interrupted, generating an electric arc. This arc is caused by the sudden change in coil current when the relay 10's coil is de-energized, resulting in a high self-induced electromotive force in the coil, which in turn generates an electric spark between the contacts. Therefore, the insulating cover 220 isolates the electric arc generated by the relay 10 during operation from the external environment and suppresses the generation and spread of the arc, thereby ensuring the safe operation of the circuit and improving the lifespan of the relay 10.

[0042] Specifically, the insulating cover 220 includes a square shell-shaped structure and forms a receiving cavity 221 with one end open. The receiving cavity 221 has an isolation post 222 protruding and extending toward the receiving cavity 221 on the cavity wall at the end away from the opening. The insulating cover 220 has a through hole 223 at the end away from the opening, which penetrates the isolation post 222 and communicates with the receiving cavity 221. The stationary contact 210 passes through the through hole 223, with one end exposed outside the insulating cover 220 and the other end passing through the through hole 223 and extending into the receiving cavity 221.

[0043] As is well known, when an electric arc occurs, the stationary contact 210 is easily ablated by the arc, producing metal particles. After the contact is ablated by the arc, the flying metal particles may contaminate the inner wall of the insulating cover 220, causing the originally insulating insulating cover 220 to be contaminated, thus forming an insulation short circuit and causing the insulation path of the insulating cover 220 to be "broken down".

[0044] It's important to explain here that "breakdown" refers to the loss of insulation capacity of electrical equipment's insulating material under certain conditions, allowing current to flow freely and potentially causing short circuits or fires. Specifically for relay 10, when an electric arc occurs, leakage current is generated. This leakage current creeps along the insulating material. When the insulation material breaks down, the previously insulated parts are no longer insulating, allowing the leakage current to flow freely. This reduces the creepage distance of the leakage current, consequently affecting circuit safety and the lifespan of relay 10.

[0045] It is easy to see that by setting the insulating post 222, the side of the stationary contact 210 can be wrapped. Therefore, when the stationary contact 210 of the relay 10 is burned by an electric arc and metal particles are generated, the metal particles can be blocked by the insulating post and will not splash onto the inner wall of the insulating cover 220. Thus, the insulation capacity of the insulating cover 220 can be prevented from decreasing.

[0046] Please continue reading. Figure 2 and Figure 3 In a preferred embodiment, the contact module 200 further includes an insulating ring 230, which is disposed in the receiving cavity 221 and coaxially sleeved on at least part of the stationary contact 210 extending into the receiving cavity 221.

[0047] Thus, by setting the insulating ring 230, the insulating ring 230 and the isolation post 222 can jointly wrap the side of the stationary contact 210, thereby preventing metal particles from splashing and contaminating the inner wall of the insulating cover 220. Furthermore, when the length specifications of the stationary contact 210 are different, only the portion of the stationary contact 210 exposed by the isolation post 222 needs to be fitted with a matching insulating ring 230 to completely wrap the stationary contact 210 together with the isolation post 222 to prevent splashing metal particles from contaminating the insulating cover 220. This eliminates the need for re-die-casting the insulating cover 220, thus significantly reducing the manufacturing cost of the relay 10.

[0048] In the embodiments of this application, the insulating cover 220 and the insulating ring 230 are made of ceramic, but this is not a limitation; any material capable of insulation is acceptable. However, since ceramic has better insulation properties and can play a role in extinguishing arcs to a certain extent, using ceramic as the material for the insulating cover 220 and the insulating ring 230 is a preferred implementation.

[0049] As a further improvement, such as Figure 4 and Figure 5 As shown, a creepage groove 231 surrounding its central axis is formed on one side of the insulating ring 230. At least two creepage gates 232 are constructed on the insulating ring 230 from the creepage groove 231. All creepage gates 232 are arranged radially around the central axis of the insulating ring 230. For example, in the embodiment shown in the figure, there is one creepage groove 231, thus forming two creepage gates 232 on the insulating ring 230. Of course, there can also be multiple creepage grooves 231, thereby forming a greater number of creepage gates 232 on the insulating ring 230.

[0050] This design creates a bent, meandering structure on the surface of the insulating ring 230, which extends the creepage distance and allows the leakage current to be gradually dissipated during the creepage process, thereby improving the insulation effect.

[0051] Furthermore, in the radial direction of the insulating ring 230 and away from its central axis, the dimensions of each creepage gate 232 in its own axial direction gradually increase or decrease. When the dimensions of each creepage gate 232 in its own axial direction gradually decrease, the creepage gate 232 near the central axis can directly block most of the splashing metal particles, providing better insulation for products requiring high voltage, high current, and few breaking cycles. When the dimensions of each creepage gate 232 in its own axial direction gradually increase, for relay 10 products requiring low voltage, low current, and many breaking cycles, since fewer metal particles are generated, although the vertical dimension of the creepage gate 232 near the central axis is smaller, it can still block most of the metal particles, thus also providing better insulation. Moreover, precisely because the vertical dimension of the creepage gate 232 near the central axis is smaller, there is a larger space inside the enclosure to elongate the arc, which is also more conducive to arc extinguishing.

[0052] See Figure 3 and Figure 4 In the structure of the stationary contact 210, the stationary contact 210 includes a connecting post 211 and a contact block 212. The connecting post 211 is used for conducting electricity, and the contact block 212 is used for contacting the moving contact piece. Therefore, the material of the connecting post 211 is a material with high conductivity, such as oxygen-free copper, while the material of the contact block 212 is a material with anti-adhesion properties, such as alloy copper. Of course, the material of the connecting post 211 is not limited to oxygen-free copper, and the material of the contact block 212 is not limited to alloy copper.

[0053] Preferably, the connecting post 211 and the contact block 212 are separate structures, which facilitates processing and reduces the processing difficulty of the stationary contact 210. For example, they can be welded, bonded, or riveted. Specifically, the connecting post 211 passes through the through hole 223 and extends into the receiving cavity 221. The contact block 212 is connected to the end of the connecting post 211 that extends into the receiving cavity 221. The insulating ring 230 is sleeved on the part of the connecting post 211 that extends into the receiving cavity 221. Further, one end of the insulating ring 230 along its own axial direction abuts against the contact block 212, and the other end abuts against the isolating post 222, thereby achieving the fixation of the insulating ring 230 without the aid of other fasteners.

[0054] In the specific structure of the connecting post 211, the connecting post 211 includes a connecting part 2111 and a protruding part 2112 that are coaxially connected. The diameter of the protruding part 2112 is larger than the diameter of the connecting part 2111, so that the protruding part 2112 extends out of the insulating cover 220 and abuts against the outer surface of the insulating cover 220. The connecting part 2111 passes through the through hole 223, and the end of the connecting part 2111 away from the protruding part 2112 is connected to the contact block 212.

[0055] For the specific structure of contact block 212, please refer to... Figure 6 The contact block 212 includes a first contact portion 2121 and two second contact portions 2122 symmetrically arranged with the central axis of the through hole 223 as the axis of symmetry. The first contact portion 2121 contacts the connecting post 211, and one side of the second contact portion 2122 abuts against the insulating ring 230, and the other side is used to contact the moving contact piece.

[0056] As can be seen, both the connecting post 211 and the insulating ring 230 are in contact with one side of the contact block 212, which increases the contact area of ​​the contact part, improves the structural stability of the contact part, and avoids the contact part from shaking.

[0057] Furthermore, in order to better fix the insulating ring 230, the two second contact portions 2122 are respectively provided with arc-shaped limiting grooves 2122a on the side facing the insulating ring 230. The maximum distance between the two limiting grooves 2122a is equal to the diameter of the insulating ring 230, and the groove width of each limiting groove 2122a is equal to the ring diameter of the insulating ring 230 (i.e., the outer diameter of the insulating ring 230 minus the inner diameter). This allows the insulating ring 230 to be confined in the limiting groove 2122a and fit against the bottom surface of the limiting groove 2122a, thus further fixing the insulating ring 230 and preventing the insulating ring 230 from moving radially.

[0058] In the embodiments of this application, there are three moving contacts, two of which each contact a second contact portion 2122, and the other moving contact contacts a first contact portion 2121. Since there are two stationary contacts 210, there are also two contact blocks 212. The opposite ends of each moving contact contact contact a pair of stationary contacts 210 to form a reliable parallel circuit. The number of contact points formed by multiple moving contacts and a single contact block 212 is greater than two, thereby achieving the effect of current shunting. Furthermore, according to the principle that the electric repulsion force is proportional to the square of the current, the above arrangement significantly reduces the magnitude of the electric repulsion force at each contact point, which is beneficial to improving the short-circuit withstand capability and thus improving the reliability of the relay 10.

[0059] Of course, in other embodiments, the structure of the contact block 212 is not limited to the structure described in the above embodiments. It is understood that the number of second contact portions 2122 in the contact block 212 may depend on the number of moving contact pieces, and is not limited here.

[0060] In summary, the contact module 200 for the relay 10 provided in this application, by setting the insulating ring 230, can not only prevent metal particles from splashing onto the inner cavity sidewall of the insulating cover 220, but also can be customized to different sizes according to the length of the stationary contact 210 and installed in the insulating cover 220, thus eliminating the need to re-die-cast the insulating cover 220, thereby significantly reducing the production cost of the relay 10.

[0061] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A contact module for a relay, characterized by include: An insulating cover, the insulating cover forming a receiving cavity with an opening at one end, the receiving cavity having an isolation post on the cavity wall at the end away from the opening, and the insulating cover having a through hole at the end away from the opening that penetrates the isolation post and communicates with the receiving cavity; A stationary contact is inserted through the through hole, with one end of the stationary contact exposed outside the insulating cover, and the other end of the stationary contact passing through the through hole and extending into the receiving cavity; An insulating ring is disposed within the receiving cavity and coaxially sleeved on at least the portion of the stationary contact that extends into the receiving cavity.

2. The contact module of claim 1, wherein, The stationary contact includes a connecting post and a contact block. The connecting post passes through the through hole and extends into the receiving cavity. The contact block is connected to one end of the connecting post that extends into the receiving cavity. An insulating ring is sleeved on the part of the connecting post that extends into the receiving cavity. One end of the insulating ring along its own axial direction abuts against the contact block, and the other end abuts against the isolation post.

3. The contact module of claim 2, wherein, The contact block includes a first contact portion and two second contact portions symmetrically arranged with the central axis of the through hole as the axis of symmetry. One side of the second contact portion abuts against the insulating ring, and the other side is used to contact the moving contact piece.

4. The contact module of claim 3, wherein, Limiting grooves are respectively formed on one side of the two second contact portions. The maximum distance between the two limiting grooves is equal to the diameter of the insulating ring, and the groove width of each limiting groove is equal to the ring diameter of the insulating ring, so that the insulating ring is confined in the limiting groove.

5. The contact module of claim 2, wherein, The contact block and the connecting column are separate structures.

6. The contact module of claim 2, wherein, The connecting post includes a connecting part and a protruding part that are coaxially connected. The diameter of the protruding part is larger than the diameter of the connecting part, so that the protruding part extends out of the insulating cover and abuts against the outer surface of the insulating cover. The connecting part passes through the through hole, and the end of the connecting part away from the protruding part is connected to the contact block.

7. The contact module of claim 1, wherein, The insulating ring has a creepage groove on one side that surrounds its central axis. The creepage groove is constructed to form at least two creepage grids on the insulating ring. All the creepage grids are arranged around the central axis of the insulating ring and are spaced apart radially along the insulating ring.

8. The contact module of claim 7, wherein, Along the radial direction of the insulating ring and away from the central axis of the insulating ring, the dimensions of each creepage gate in its own axial direction gradually increase or decrease.

9. The contact module of claim 1, wherein, The insulating ring is made of ceramic.

10. A relay characterized by comprising: include: The contact module as described in any one of claims 1-9; A movable contact piece, which is movably disposed within the receiving cavity of the insulating cover; An electromagnetic drive module is used to drive the moving contact to move between a closed position where it is in electrical contact with the stationary contact and an open position where it is separated from the stationary contact.

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