Sealed electromagnetic relay

Abstract

The utility model relates to a sealed electromagnetic relay which comprises a fixing plate, a plurality of pins and a control unit, the fixing plate is provided with bonding pads, the control unit is arranged on one side of the fixing plate and connected to the pins, and the pins penetrate through the corresponding bonding pads and are connected to the corresponding bonding pads in a welded mode through first welding flux. The pin is provided with a welding end welded with an external circuit board, and the welding end is used for being in welding connection with the external circuit board through second welding flux with the melting point lower than or not higher than that of the first welding flux, so that when the pin and the external circuit board are welded through the first welding flux or the electromagnetic relay is applied to a high-temperature environment, the first welding flux is not prone to melting to generate a gap; and moreover, the pins can be well positioned and fixed, and the technical problem that the electrical life of the electromagnetic relay in a relatively high temperature environment is relatively poor due to the fact that mechanical parameters of the electromagnetic relay are easy to change is solved.

Description

Technical Field

[0001] This application relates to the field of relay technology, and in particular to a sealed electromagnetic relay. Background Technology

[0002] Currently, in traditional electromagnetic relays, the pins connecting the moving and stationary reeds are generally mounted on a plastic base, and the pins and base are fixed together by filling the gap between the pins and the base with epoxy resin glue.

[0003] However, because electromagnetic relays need to be soldered onto external circuit boards at high temperatures, the epoxy resin melts when heated, causing gaps or leaks in the adhesive at the leads after soldering. This leads to relay encapsulation failure, making it difficult for traditionally encapsulated electromagnetic relays to meet sealing requirements in scenarios with high sealing demands. Especially when electromagnetic relays are used in liquid environments, they need to be immersed in the liquid to operate, thus requiring even higher sealing performance. To address this issue, patent CN202111063315.7, "An Electromagnetic Relay and Relay Device Immersable in a Liquid-Cooled Environment," proposes a solution of extending the leads and flipping them into another housing before potting. This solution has a complex structure and process, resulting in relatively high costs.

[0004] In addition, since the base of a traditional electromagnetic relay is made of plastic, when the electromagnetic relay is used in a high-temperature environment or when the pins are soldered to an external circuit board, the spring inserts into the base are prone to stress release. Coupled with the high temperature in the high-temperature environment, the above factors can easily cause the plastic base to deform, resulting in changes in the mechanical parameters of the electromagnetic relay, and thus making the electromagnetic relay perform poorly in high-temperature environments. Utility Model Content

[0005] Therefore, it is necessary to provide a sealed electromagnetic relay that can solve the above-mentioned technical problems, such as the complex structure and process of traditional electromagnetic relays in order to improve sealing performance, and the easy deformation of traditional plastic bases, which leads to changes in the mechanical parameters of electromagnetic relays and thus poor electrical life performance of electromagnetic relays in high-temperature environments.

[0006] According to one aspect of this application, a sealed electromagnetic relay is provided, including a mounting plate, a control unit, and pins, wherein the control unit is disposed on one side of the mounting plate and connected to the pins;

[0007] The fixing plate has solder pads, and solder holes are formed on the solder pads;

[0008] The pin passes through the corresponding solder hole and is soldered to the corresponding pad by a first solder. The pin has a solder end that is soldered to an external circuit board. The solder end is soldered to the external circuit board by a second solder with a melting point not higher than that of the first solder.

[0009] In one embodiment, the electromagnetic relay further includes a housing and a control unit, the control unit being disposed within the housing and connected to the pin, one end of the housing having an opening, a fixing plate closing the opening of the housing, and the four edges of the fixing plate being sealed to the inner wall of the housing.

[0010] In one embodiment, the four edges of the fixing plate are sealed to the inner wall of the housing by sealant.

[0011] And / or, the surface of the fixing plate facing the welding side forms a sealing position with the inner wall of the outer casing, and the sealing position is filled with the sealant.

[0012] In one embodiment, the control unit has a plurality of pins, and the pins connected to each control unit pass through a corresponding solder hole on the fixing plate and are soldered to a corresponding pad by the first solder. The fixing plate is a circuit board on which circuits are arranged so that all the control units are electrically connected to each other.

[0013] In one embodiment, the electromagnetic relay further includes a housing with one end open and enclosing all the control units inside, and a mounting plate closing the opening of the housing and sealingly connecting it to the housing.

[0014] In one embodiment, the fixing plate is a PCB board, and the melting point of the first solder is greater than or equal to 290°C.

[0015] In one embodiment, the pads and the walls of the solder holes are covered with a conductive layer, and the first solder covers the conductive layer and fills the gap between the pins and the walls of the solder holes.

[0016] In one embodiment, the conductive layer is covered with a flux layer, and the first solder covers the flux layer.

[0017] In one embodiment, the pins include a first pin and a second pin; the control unit includes a contact portion and a magnetic circuit portion, the contact portion includes a normally open stationary spring and a moving spring, the normally open stationary spring is connected to the first pin, the moving spring is connected to the second pin, and the magnetic circuit portion includes a coil and an armature push block connected to the moving spring;

[0018] When the coil is energized, the armature push block can push the moving spring to move and cause the moving spring to elastically deform under the action of the electromagnetic force generated by the coil being energized, so as to contact the normally open stationary spring;

[0019] When the coil is de-energized, the moving spring can drive the armature push block to reset together under the action of the elastic force generated by its own elastic deformation, so as to disengage from the normally open stationary spring.

[0020] In one embodiment, the pins further include a third pin and a fourth pin, and the contact portion further includes a normally closed stationary spring, the third pin being connected to the normally closed stationary spring, and the fourth pin being connected to the coil.

[0021] Compared with the prior art, this application has the following advantages:

[0022] 1. The sealed electromagnetic relay provided in this application adopts a fixed plate with multiple pads, and multiple pins are passed through the fixed plate with multiple pads. By using a first solder with a higher melting point to solder the pins to the pads of the fixed plate, the first solder at the soldering point between the pins and the fixed plate is less likely to melt and create gaps when the pins are soldered to an external circuit board using a second solder with a lower melting point than the first solder or when the electromagnetic relay is applied to a high-temperature environment, thereby achieving higher sealing performance.

[0023] 2. The sealed electromagnetic relay provided in this application cleverly utilizes the high-temperature resistance of the PCB board by preferably using it as the fixing plate. This makes the PCB board less prone to deformation when the electromagnetic relay is used in high-temperature environments or when the pins are soldered to external circuit boards. The mechanical parameters of the components inserted into the PCB board are less affected by the high-temperature environment, thus solving the technical problem that the mechanical parameters of the electromagnetic relay are prone to change, resulting in poor electrical life performance of the electromagnetic relay in high-temperature environments. This gives the electromagnetic relay better high-temperature electrical life performance. At the same time, it also cleverly utilizes the characteristics of the PCB board's own pads, taking advantage of the performance of the pads and the conventional low cost of the PCB board to achieve a sealing solution. The entire solution requires no special processes or special customization, is simple, and has a significant sealing effect.

[0024] 3. The sealed electromagnetic relay provided in this application covers the pads on both sides of the fixed plate and the wall of the solder hole with a conductive layer, so that the pads on both sides and the inner wall of the solder hole are connected as one through the conductive layer. During welding, the first solder after being heated and melted is covered by gravity (or wave impact force if it is wave soldering) and tension to cover the gap between the pads and the pins and the solder hole, thus welding the conductive layer of the pins, pads and the inner wall of the solder hole together.

[0025] 4. To improve the welding quality, it is preferable to cover the conductive layer on the side away from the pad with a flux layer. This effectively utilizes the characteristics of the metal plating on the pad, gravity, and surface tension. When the first solder melts, it can automatically fill the gap between the pad, pin, and solder hole to form a large contact area of ​​sealed whole, rather than just sticking to the pin and hole, resulting in a better sealing effect. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the appearance of a sealed electromagnetic relay provided in an embodiment of this application.

[0027] Figure 2 This is a schematic diagram of the internal structure of a sealed electromagnetic relay provided in an embodiment of this application.

[0028] Figure 3 This is a cross-sectional view of the internal structure of a sealed electromagnetic relay provided in an embodiment of this application.

[0029] Figure 4 A cross-sectional view showing pins soldered to pads on a PCB board, according to an embodiment of this application.

[0030] Figure 5 An exploded view of the magnetic circuit portion in a sealed electromagnetic relay provided in an embodiment of this application.

[0031] Figure 6 This is a schematic diagram of the internal structure of a sealed electromagnetic relay provided in another embodiment of this application.

[0032] Figure 7 This is a schematic diagram of the appearance of a sealed electromagnetic relay provided in another embodiment of this application.

[0033] Figure 8 This is a schematic diagram of the assembly steps of a sealed electromagnetic relay provided in an embodiment of this application.

[0034] Figure 9 This is a schematic diagram of the positioning fixture used for assembling a hermetically sealed electromagnetic relay according to an embodiment of this application. Figure 1 .

[0035] Figure 10 This is a schematic diagram of the positioning fixture used for assembling a hermetically sealed electromagnetic relay according to an embodiment of this application. Figure 2 .

[0036] Figure 11 This is a cross-sectional view of a positioning fixture used for assembling a hermetically sealed electromagnetic relay provided in an embodiment of this application.

[0037] Figure 12 This is a schematic diagram of the appearance of the insulating shell in a sealed electromagnetic relay provided in an embodiment of this application.

[0038] Figure 13 This is a schematic diagram showing the control unit and pins fixed in a positioning fixture during assembly of a sealed electromagnetic relay provided in an embodiment of this application.

[0039] Figure 14 This is a schematic diagram showing the control unit and pins fixed in a positioning fixture during assembly of a sealed electromagnetic relay provided in another embodiment of this application.

[0040] Explanation of reference numerals in the attached figures:

[0041] 10. Electromagnetic relay; 100. Housing; 200. Control unit; 210. Contact part; 211. Normally open stationary spring; 212. Normally closed stationary spring; 213. Moving spring; 220. Magnetic circuit part; 221. Coil; 222. Armature push block; 223. Insulating shell; 223a. Shell shoulder; 300. Pin; 310. First pin; 320. Second pin; 330. Third pin; 340. Fourth pin; 400. Fixture plate; 401. Welding side; 402. Mounting side; 403. Welding pad; 404. Welding hole; 50. Positioning fixture; 51. Fixture shell; 52. Spring; 521. First spring; 522. Second spring; 523. Third spring; 524. Fourth spring; 525. Fifth spring; 60. First solder; 70. Conductive layer; 80. Flux layer. Detailed Implementation

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] This application provides a sealed electromagnetic relay, which is used in automatic control circuits 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 state of the circuit between the load power supply and the load, thereby protecting the load through circuit switching and automatic adjustment, and preventing the load from being damaged by excessive current.

[0049] The structure of the sealed electromagnetic relay in this application and the assembly steps of the sealed electromagnetic relay are described below. It is understood that the sealed electromagnetic relay of this application can be any electronic relay used in fields such as industrial control, automation, mechanical equipment, new energy, and chemical engineering, and is not limited thereto.

[0050] See Figures 1 to 3 , Figure 1 This paper shows a schematic diagram of the appearance of a sealed electromagnetic relay (hereinafter referred to as electromagnetic relay 10) according to an embodiment of this application. Figure 2 A schematic diagram of the internal structure of the electromagnetic relay 10 in this embodiment is shown. Figure 3 A cross-sectional view of the internal structure of the electromagnetic relay 10 is shown. An embodiment of the electromagnetic relay 10 provided in this application includes a housing 100, a control unit 200, pins 300, and a mounting plate 400. The control unit 200 is disposed within the housing 100, and one end of the housing 100 has an opening. The mounting plate 400 closes the opening of the housing 100 and is sealed to the housing 100. Its opposite sides are defined as a mounting side 402 and a soldering side 401, respectively. The control unit 200 is located on the mounting side 402. Multiple pins 300 are connected to the control unit 200 and pass through the mounting plate 400, such that one end of each pin 300 is exposed on the mounting plate 400 and located on the soldering side 401. The end of the pin 300 located on the soldering side 401 is defined as the soldering end, which is used for soldering to an external circuit board. This allows the control unit 200 to be electrically connected to the external circuit board, enabling the control unit 200 to control the circuit switching of the external circuit board or to control the circuit switching of the electromagnetic relay 10 itself.

[0051] Specifically, in one embodiment, such as Figure 2 and Figure 3 As shown, the multiple pins 300 include a first pin 310, a second pin 320, a third pin 330, and a fourth pin 340. The control unit 200 includes a contact portion 210 and a magnetic circuit portion 220. The contact portion 210 includes a normally open stationary spring 211, a normally closed stationary spring 212, and a moving spring 213. The normally open stationary spring 211 is connected to the first pin 310, the moving spring 213 is connected to the second pin 320, and the normally closed stationary spring 212 is connected to the third pin 330. Combined with... Figure 5 As shown, the magnetic circuit section 220 includes a coil 221 connected to the fourth pin 340 and an armature push block 222 connected to the moving spring 213. After all pins 300 are soldered to the external circuit board, the first pin 310 is connected to the load power supply of the external circuit board, and the second pin 320 is connected to the load of the external circuit board. The external circuit board can control the coil 221 to be energized or de-energized through the fourth pin 340.

[0052] When coil 221 is energized, it generates electromagnetic force. Under this force, armature push block 222 moves the moving spring 213, causing it to elastically deform and contact the normally open stationary spring 211. At this point, the moving spring 213, the external circuit board, and the normally open stationary spring 211 form a normally open circuit, allowing the load power supply and the load to conduct electricity. When coil 221 is de-energized, the electromagnetic force disappears. The moving spring 213, under the elastic force generated by its own deformation, drives armature push block 222 to reset, disengaging from the normally open stationary spring 211. At this point, the moving spring 213 contacts the normally closed stationary spring 212, forming a normally closed circuit, disconnecting the load power supply and the load. Through these actions, control unit 200 achieves the purpose of controlling the circuit switching of the external circuit board.

[0053] It is understood that in other embodiments, the normally closed stationary spring 212 may not be provided, and / or the coil 221 may not be connected to the external circuit board through pin 300, that is, the coil 221 may not be controlled by the external circuit board to be energized or de-energized. In this case, the third pin 330 and the fourth pin 340 may not be included among all pins 300, as long as the first pin 310 and the second pin 320 are included. However, it is obvious that by providing the normally closed stationary spring 212, the movement of the moving spring 213 can be blocked when the moving spring 213 is reset, so as to reduce the vibration of the moving spring 213 and speed up the process of bringing the moving spring 213 to a stationary state; and by connecting the coil 221 to the external circuit board through the fourth pin 340, it is not necessary to power the coil 221 with an external power supply. Therefore, the structure of the electromagnetic relay 10 can be simplified, which is obviously the best embodiment.

[0054] It is also understood that in other embodiments, the electromagnetic relay 10 may not include the housing 100. In this case, the electromagnetic relay 10 can still perform its function of connecting or disconnecting the load circuit, but by providing the housing 100, the control unit 200 can be protected and sealed, so that the electromagnetic relay 10 can be used in harsh environments such as liquid-cooled environments or high-temperature environments.

[0055] However, it is worth noting that in traditional electromagnetic relays, the pin 300 connecting the moving and stationary reeds is typically mounted on a plastic base, with the pin 300 fixed to the base. Because the base in traditional electromagnetic relays is made of plastic, when the relay is used in high-temperature environments or when the pin 300 is soldered to an external circuit board, stress release can easily occur when the reed is inserted into the base. Furthermore, the high temperatures in these environments can cause the plastic base to deform, leading to changes in the mechanical parameters of the electromagnetic relay (e.g., a decrease or increase in overtravel). This, in turn, results in a poorer electrical lifespan for the electromagnetic relay in higher-temperature environments.

[0056] It is also worth noting that in traditional electromagnetic relays, after the housing 100 is sealed to the base, the pins 300 and the base are fixed together by filling the gap between the pins 300 and the base with epoxy resin. When the pins 300 are soldered to the external circuit board, the epoxy resin will melt when heated, causing the encapsulation of the electromagnetic relay to fail. Therefore, when the sealing requirements of the electromagnetic relay are strict, such as when it is used in harsh environments such as liquid cooling or high temperature environments, it will damage the electromagnetic relay. If the sealing performance of the electromagnetic relay is to be guaranteed, such as when it is immersed in liquid, it is necessary to use multi-layer potting encapsulation or extend the pins and invert them into another housing before potting. This not only makes the structure and process complex, but also increases the production cost.

[0057] In other embodiments, the electromagnetic relay is a coupled relay composed of several control units 200 electrically connected together, and the encapsulation also requires multiple housings 100 for encapsulation, which not only takes up space but also has poor sealing performance.

[0058] Therefore, to address the aforementioned problems, the applicant of this application conceived of improving the traditional electromagnetic relay 10. Please continue reading. Figure 2 and Figure 3 In the improved embodiment, the fixing plate 400 can be a PCB board (i.e., a circuit board or a fixing plate 400 of the same material as a circuit board), and the fixing plate 400 has multiple solder pads 403 (e.g., Figure 4 As shown, each pad 403 has a solder hole 404, allowing each pin 300 to pass through a corresponding solder hole 404 and be soldered to the corresponding pad 403 using a first solder 60. The melting point of the first solder 60 is not lower than the melting point of the second solder used to solder the pin 300 to the external circuit board. For example, the first solder 60 is a high-melting-point material with a melting point greater than that of ordinary solder, such as high-melting-point tin, with a melting point greater than or equal to 290°C, for example, 290°C-350°C, but not limited to this; while the second solder is a low-melting-point material, such as ordinary melting-point tin, with a melting point of 240°C-260°C, or it can be silver paste with a melting point of around 125°C, but not limited to this.

[0059] Thus, under the premise that the fixing plate 400 and the outer shell 100 are sealed together, and when the pin 300 is soldered to the external circuit board by the second solder, the first solder 60 will not melt at the melting point of the second solder. Or when the electromagnetic relay 10 is applied to a high-temperature environment, the first solder 60 at the soldering point between the pin 300 and the fixing plate 400 is not easy to melt and produce gaps. Therefore, the improved electromagnetic relay 10 has higher sealing performance and achieves the technical effect of the electromagnetic relay 10 not leaking and failing in a liquid-cooled environment without the need for multi-layer potting and plastic sealing.

[0060] Because there is no need for multi-layer potting for sealing, a simpler structure can be used to seal the fixing plate 400 and the outer shell 100. For example, the four edges of the fixing plate 400 and the inner wall of the outer shell 100 can be sealed and connected with less sealant. Alternatively, a layer of sealant can be injected into the sealing position formed by the side of the fixing plate 400 facing the welding side 401 and the four inner walls of the outer shell 100 to fill the sealing position.

[0061] As can be seen, through the improvements in the above embodiments, the electromagnetic relay 10 can achieve better sealing performance with a smaller installation space and fewer parts. Furthermore, since the mounting plate 400 can be a PCB board, and commonly used materials for PCB boards include epoxy resin (FR-4), high-temperature FR-4, metal substrate, polyimide (PI), fluoroplastics (PTFE), ceramics, etc., the inherent high-temperature resistance of the PCB board is cleverly utilized. This ensures that the PCB board is not easily deformed when the electromagnetic relay 10 is used in high-temperature environments or when the pins 300 are soldered to an external circuit board. The mechanical parameters of components mounted on the PCB board are less affected by the high-temperature environment, thus solving the problem of… The mechanical parameters of the electromagnetic relay 10 are prone to change, leading to poor electrical life performance in high-temperature environments. This solution aims to improve the high-temperature electrical life performance of the electromagnetic relay 10. Furthermore, because the PCB board itself has pads 403, the pins 300 can be soldered to the PCB board using these pads. Therefore, the sealing solution is achieved by leveraging the performance of the pads 403 and the conventional low cost of the PCB board. The entire solution requires no special processes or customization, is simple, and improves the sealing effect while reducing the assembly steps of the electromagnetic relay 10, saving material and labor costs. Of course, the fixing plate 400 is not limited to a PCB board; it can also be other fixing plates 400 with pads 403, which is not limited here.

[0062] Further, see Figure 4 , Figure 4 A cross-sectional schematic diagram of the fixing plate 400 in a preferred embodiment is shown. Figure 4 In the illustrated embodiment, the walls of the pads 403 and the holes 404 are covered with a conductive layer 70. A first solder 60 covers the conductive layer 70 and fills the gap between the pins and the walls of the holes 404. Exemplarily, the conductive layer 70 can be a copper foil, or it can be a coating formed of other conductive materials. This allows the pads 403 on both sides of the fixing plate 400 to be interconnected through the conductive layer 70. During soldering, the first solder 60, after being heated and melted, is subjected to gravity (or wave impact force in wave soldering) and tension to cover the gap between the pads 403 and the pins and the holes 404, thus soldering the pins 300, the pads 403, and the conductive layer 70 on the inner walls of the holes 404 together.

[0063] Preferably, to improve the welding quality, a flux layer 80 can be covered on the conductive layer 70, and the first solder 60 covers the flux layer 80. The flux layer 80 can be a layer of gold plated on the conductive layer 70 or a layer of tin sprayed on the conductive layer 70, or it can be flux. This effectively utilizes the characteristics of the metal plated on the pad 403 and gravity and surface tension. In this way, when the solder melts, it can automatically fill the gap between the pad 403, the pin and the solder hole 404, thereby forming a sealed whole with a large contact area, instead of just sticking to the pin 300 and the solder hole 404. This allows the first solder 60 to tightly connect the fixing plate 400, the pad 403 and the pin 300, resulting in a better sealing effect.

[0064] More preferably, the contact area between the first solder 60 and the fixing plate 400 can be increased by increasing the size of the solder pad 403, so as to further improve the sealing performance.

[0065] See Figure 6 This is an improved embodiment of the electromagnetic relay 10, which is the coupling relay mentioned above. It is composed of several control units 200 electrically connected to each other. The structure of the control unit 200 is the same as that of the control unit 200 in the electromagnetic relay 10 with only a single control unit 200, and will not be described again here. Specifically, in this embodiment, the fixing plate 400 can be a PCB board without circuitry, serving only as a fixing and sealing board, or it can be a PCB board with circuitry. Each pin 300 connected to each control unit 200 passes through a corresponding solder hole 404 on the fixing plate 400 and is also soldered to a corresponding pad 403 on the fixing plate 400 using the first solder 60, so that all control units 200 can be electrically connected to each other through the circuit board. Of course, all pins 300 can also be connected to an external circuit board to achieve mutual electrical connection. In this way, the control unit 200 can control the circuit on / off of the external circuit board or the electromagnetic relay 10 itself.

[0066] Further, see Figure 7 The electromagnetic relay 10 in this embodiment also includes a housing 100. One end of the housing 100 is open and encloses all the control units 200 inside it. Similarly, the fixing plate 400 closes the opening of the housing 100 and is sealed to the housing 100. The sealing structure is the same as that described in the previous embodiment, and will not be repeated here. Of course, the housing 100 may not be provided, or the control unit 200, the fixing plate 400, and the external circuit board may share a single housing 100. There is no limitation here.

[0067] As can be seen, the improved coupling relay, by connecting several control units 200 together to a fixed plate 400 and sharing a housing 100, not only achieves the same technical effects as the electromagnetic relay 10 composed of a single control unit 200, such as good sealing and the fixed plate 400 being resistant to high temperature and not easily deformed, but also reduces the number of housings 100 and fixed plates 400. Therefore, it simplifies the structure, reduces the installation volume and the number of overall parts, thereby reducing the cost.

[0068] The following is combined Figures 8 to 14 The specific assembly steps of the electromagnetic relay 10 provided in this application are described.

[0069] S1, the positioning fixture 50 is used to position the control unit 200 and multiple pins 300. Specifically, as follows: Figures 9 to 12 As shown, the positioning fixture 50 includes a fixture housing 51 and multiple spring clips 52 disposed within the fixture housing 51. The fixture housing 51 is used to cover the control unit 200 and the pin 300 within the fixture housing 51. Some of the spring clips 52 are used to abut against the pin 300, and other spring clips 52 are used to abut against the control unit 200, so that in this step, the positioning fixture 50 can be used to position the pin 300 and the control unit 200. Figure 10 and Figure 11 Positioning is performed using the X and Y directions shown.

[0070] In one specific implementation, see Figure 2 , Figure 3 and Figure 12 The control unit 200 in the electromagnetic relay 10 also includes an insulating housing 223, and the coil 221 is disposed in the insulating housing 223; see reference Figures 9 to 11 The multiple spring clips 52 disposed within the tooling housing 51 include a first spring clip 521, a second spring clip 522, a third spring clip 523, a fourth spring clip 524, and a fifth spring clip 525, wherein the first spring clip 521, the second spring clip 522, the third spring clip 523, and the fourth spring clip 524 each have two spring clips, such as... Figure 13 As shown, two first spring contacts 521 abut against a corresponding first pin 310, two second spring contacts 522 abut against a corresponding second pin 320, and two third spring contacts 523 abut against a corresponding third pin 330, as... Figure 12 As shown, the two fourth springs 524 abut against the two shoulders 223a of the insulating shell 223, and the fifth spring 52552 abuts against the core section of the magnetic circuit 220.

[0071] Better, such as Figure 10 , Figure 11 and Figure 13As shown, the tooling housing 51 has stepped surfaces, positioning grooves, and baffles, which abut against the features of the control unit 200 to assist in positioning. Combined with the positioning of the spring piece 52, this allows for omnidirectional positioning of the control unit 200 and the pins 300. More preferably, the tooling housing 51 is made of high-temperature resistant metal or polymer materials, thus preventing deformation in high-temperature environments.

[0072] S2, each pin 300 is passed through a corresponding pad 403 on the mounting plate 400. As mentioned above, the mounting plate 400 has multiple pads 403, and each pad 403 has a solder hole 404. Each pin 300 is passed through a pad 403 on the mounting plate 400, so that the control unit 200 is located on the mounting side 402 of the mounting plate 400, and the soldering end of the pin 300 is located on the soldering side 401 of the mounting plate 400.

[0073] S3, the pins 300 are soldered to the corresponding pads 403 using the first solder 60 to fix the control unit 200 onto the mounting plate 400. In some embodiments, the control unit 200 includes a magnetic circuit portion 220 and a contact portion 210. The contact portion 210 includes an armature pusher block 222. In the initial state, the armature pusher block 222 and the magnetic circuit portion 220 can be separated from each other or connected to each other in the initial state. Therefore, after soldering the pads 403 corresponding to the pins 300 to each other using the first solder 60, the magnetic circuit portion 220 can be fixed to the mounting plate 400 first, and then the armature pusher block 222 can be installed onto the magnetic circuit portion 220 to complete the fixed connection between the control unit 200 and the mounting plate 400; alternatively, the pins 300 can be passed through the mounting plate 400 and the pins 300 can be soldered to the corresponding pads 403 to be securely fixed, and then the armature pusher block 222 can be inserted to fix the control unit 200 to the mounting plate 400. In this step, welding can be done manually or by reflow soldering using a machine; there is no specific limitation.

[0074] As can be seen, by using the positioning fixture 50 to fix the control unit 200 and the pin 300 before connecting the fixing plate 400 and the pin 300 to each other, the simple structure of the fixing plate 400 can be used to achieve precise positioning with the pin 300. This simplifies the assembly steps and greatly simplifies the structure of the electromagnetic relay 10. There is no need to make complex designs for the fixing plate 400, thus saving the manufacturing cost of the relay.

[0075] Furthermore, if the electromagnetic relay 10 includes a housing 100, then after step S3 above, the following step is also included:

[0076] S4. The control unit 200 is enclosed in the housing 100 using the housing 100, and the fixing plate 400 closes one end opening of the housing 100.

[0077] S5. Use sealant to seal the fixing plate 400 to the housing 100, thereby completing the assembly of the electromagnetic relay 10. As mentioned above, in this step, the sealing method can be to seal the fixing plate 400 to the inner wall of the housing 100 with a small amount of sealant, or to fill the sealing position formed by injecting a layer of sealant into the sealing position formed by the side of the fixing plate 400 facing the welding side 401 and the inner wall of the housing 100.

[0078] It should be noted that if the electromagnetic relay 10 is a coupling relay, and the control unit 200 has several of them, in step S1, such as Figure 5 and Figure 14 As shown, firstly, several positioning fixtures 50 are used to position the corresponding control units 200 respectively; in step S3, the pins 300 connected to all control units 200 are soldered to a fixing plate 400; then combined with Figure 6 As shown, in step S4, the housing 100 encloses all the control units 200 inside itself, which can simplify the structure and reduce the installation volume and the number of overall parts.

[0079] Therefore, the electromagnetic relay 10 assembled using the above assembly method not only has good sealing performance, but also, because the high-temperature resistant PCB board is not easily deformed, the spring and control unit 200 fixedly connected to the PCB board (i.e., the fixing plate 400) are firmly fixed, making the mechanical performance of the electromagnetic relay 10 stable and the mechanical parameters less affected by the high-temperature environment. Therefore, the high-temperature electrical life of the electromagnetic relay 10 can be greatly improved, perfectly solving a series of problems existing in the traditional electromagnetic relay 10.

[0080] 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.

[0081] 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 sealed electromagnetic relay comprising a fixed plate, a control unit and a pin, the control unit being provided on one side of the fixed plate and connected to the pin, characterized in that : The fixing plate is provided with pads, and the pads are provided with welding holes; The pins pass through the corresponding welding holes and are connected to the corresponding pads by first soldering; the pins are provided with welding ends for welding with external circuit boards; the welding ends are connected to the external circuit boards by second soldering with a melting point lower than that of the first soldering.

2. The sealed electromagnetic relay according to claim 1, characterized by The electromagnetic relay further comprises a housing, the control units are arranged in the housing and connected to the pins, one end of the housing is provided with an opening, and the fixing plate seals the opening of the housing and is sealingly connected to the inner wall of the housing.

3. The sealed electromagnetic relay according to claim 2, characterized in that, The periphery of the fixing plate is sealingly connected to the inner wall of the housing by sealing glue; The side surface of the fixing plate towards the welding side is provided with a sealing position relative to the periphery of the housing, and the sealing position is filled with the sealing glue.

4. The sealed electromagnetic relay according to claim 1, characterized by The control units are connected to the pins which pass through the corresponding welding holes of the fixing plate and are connected to the corresponding pads by the first soldering; the fixing plate is a circuit board, and the circuit board is provided with a circuit to electrically connect all the control units.

5. The sealed electromagnetic relay according to claim 4, characterized in that, The electromagnetic relay further comprises a housing, the housing is provided with an opening at one end and covers all the control units inside, and the fixing plate seals the opening of the housing and is sealingly connected to the housing.

6. The sealed electromagnetic relay according to claim 1, characterized in that, The fixing plate is a PCB board, and the melting point of the first soldering is greater than or equal to 290 DEG C.

7. The sealed electromagnetic relay according to claim 1, characterized in that, The pads and the hole walls of the welding holes are covered with a conductive layer, and the first soldering covers the conductive layer and fills the gap between the pins and the hole walls of the welding holes.

8. The sealed electromagnetic relay according to claim 7, characterized in that, The conductive layer is covered with a soldering layer, and the first soldering covers the soldering layer.

9. The sealed electromagnetic relay according to claim 1, characterized in that, The pins include first pins and second pins; the control units include a contact part and a magnetic circuit part, the contact part includes a normally open static spring and a moving spring, the normally open static spring is connected to the first pins, the moving spring is connected to the second pins, and the magnetic circuit part includes a coil and an armature pushing block connected to the moving spring; When the coil is powered, the armature pushing block can push the moving spring to move and make the moving spring elastically deform to contact the normally open static spring under the electromagnetic force generated by the power supply of the coil; When the coil is powered off, the moving spring can drive the armature pushing block to reset together under the elastic force generated by the elastic deformation of the moving spring to separate from the normally open static spring.

10. The sealed electromagnetic relay according to claim 9, characterized in that, The pins further include third pins and fourth pins, the contact part further includes a normally closed static spring, the third pins are connected to the normally closed static spring, and the fourth pins are connected to the coil.

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