An assembly structure for preventing moving contacts from sticking together and the resulting relay
By setting a clearance groove in the housing injection mold, the problem of the moving contact sticking to the housing injection mold is solved, enabling the relay to operate normally and dissipate heat under high current impact, thus improving product reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GREE ELECTRICHEFEI
- Filing Date
- 2025-06-16
- Publication Date
- 2026-06-30
Smart Images
Figure CN224437515U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of relay structure improvement, and in particular to an assembly structure for preventing moving contacts from sticking together and the relay formed therefrom. Background Technology
[0002] Electromagnetic relays, as one of the core components in air conditioning systems, are widely used. In air conditioning, electromagnetic relays are mainly used to connect and disconnect loads such as compressors, motors, and four-way valves, acting as switches. With the widespread adoption of inverter air conditioners, a common industry-wide failure mode is concentrated at the relay contact points, primarily due to insufficient current surge resistance at the contacts.
[0003] like Figures 1-2 As shown, the relay includes a molded housing and a stationary contact and a moving contact located inside the molded housing. The stationary contact and the moving contact are arranged opposite to each other, and the moving contact can abut against or separate from the stationary contact under the action of a driving component. The end of the moving contact away from the stationary contact is arranged opposite to the molded housing, and a certain gap is maintained between them.
[0004] In actual use, a relay experiences a surge of 4 to 6 times its operating current upon activation. However, current relay performance testing typically uses the rated load for current surge resistance testing, which can lead to insufficient assessment of the contact's current surge resistance. This results in relays failing to activate or conduct in actual use, even if they pass performance testing. Disassembly of the relay reveals that the failure is primarily due to adhesion between the moving contact and the molded housing. This is because the high current surge upon activation causes the contact to shift position during reset at high temperatures, leading to adhesion to the molded housing. Furthermore, this failure cannot be detected during the current surge resistance assessment, necessitating a new assembly structure to prevent moving contact failure. Utility Model Content
[0005] To overcome the problems existing in related technologies, one of the objectives of this utility model is to provide an assembly structure that prevents moving contacts from sticking together. When the moving contact is separated from the stationary contact, sufficient gap can be maintained between the moving contact and the housing injection molded part to prevent the moving contact and the housing injection molded part from sticking together under high current impact, thus affecting the normal operation of the relay.
[0006] An assembly structure for preventing moving contacts from sticking together includes a housing injection molded part and stationary and moving contacts located inside the housing injection molded part.
[0007] The first end of the moving contact is disposed opposite to the stationary contact, and the second end of the moving contact is disposed separately from the injection molded housing; a driving component is connected to the side of the moving contact; the driving component can drive the moving contact to move towards or away from the stationary contact;
[0008] The housing injection molded part is provided with a clearance groove, which is directly opposite the second end of the moving contact.
[0009] This application provides a clearance groove in the injection molded housing part, which is directly opposite the second end of the moving contact. In this way, when the moving contact is separated from the stationary contact, a sufficient gap can be maintained between the moving contact and the injection molded housing part, so as to prevent the moving contact and the injection molded housing part from sticking together under high current impact, which would affect the normal operation of the relay.
[0010] In a preferred embodiment of this invention, the cross-sectional area of the clearance groove is greater than the cross-sectional area of the second end of the moving contact in the plane parallel to the second end of the moving contact.
[0011] In this application, the housing injection molded part refers to the integral structure surrounding the moving contact and the stationary contact. The second end of the moving contact is only adjacent to a plane in the housing injection molded part, and the second end of the moving contact is parallel to this plane. In the prior art, there is a certain gap between the second end of the moving contact and the plane, allowing the moving contact to move relative to the plane. This application provides an additional clearance groove within this plane, increasing the distance between the second end of the moving contact and the plane, preventing the moving contact from contacting and sticking to the plane under high current impact. To achieve a better clearance effect, this application sets the cross-sectional area of the clearance groove to be larger than the cross-sectional area of the second end of the moving contact, ensuring sufficient space between the moving contact and the plane, and preventing the second end of the moving contact from contacting the housing injection molded part. The application provides a larger clearance groove, which also serves to dissipate heat from the moving contact. Since air has a high thermal conductivity, the heat in the moving contact can be dissipated in time through the clearance groove, preventing the overall temperature of the relay from becoming too high, and also preventing the temperature of the second end of the moving contact from becoming too high, which could cause the injection molded housing directly opposite it to melt at high temperature, resulting in deformation and adhesion.
[0012] In a preferred embodiment of this invention, the second end of the moving contact is a cuboid, and the clearance groove is a cuboid-shaped groove. In a plane parallel to the second end of the moving contact, the length of the clearance groove is twice the length of the second end of the moving contact, and the width of the clearance groove is twice the width of the second end of the moving contact.
[0013] In this application, the second end of the moving contact is set to a cuboid, and correspondingly, the clearance groove is also a cuboid structure. In order to achieve better clearance effect and heat dissipation function, the length and width of the clearance groove are both twice that of the second end of the moving contact. In this way, it can ensure that there is enough space between the second end of the moving contact and the housing injection molded part, and also achieve a better heat dissipation effect. At the same time, the larger volume of the clearance groove also helps the housing injection molded part to be demolded and reduces the injection molding difficulty of the housing injection molded part.
[0014] In a preferred embodiment of this invention, the depth of the clearance groove is 0.2-0.5 mm.
[0015] Since there is a certain gap between the housing injection part and the second end of the moving contact, setting the depth of the clearance groove in the range of 0.2-0.5mm can meet the clearance requirements, the heat dissipation requirements, and the injection molding difficulty of the housing injection part.
[0016] In a preferred embodiment of this invention, the vertical distance between the second end of the moving contact and the bottom of the clearance groove is greater than 1 mm.
[0017] Since there is a certain gap between the housing injection molded part and the second end of the moving contact, the depth of the relief groove is set in the range of 0.2-0.5mm. By controlling the relative position between the housing injection molded part and the moving contact, it can be ensured that the vertical distance between the second end of the moving contact and the bottom of the relief groove is greater than 1mm. At this distance, it can be ensured that under high current excitation, the second end of the moving contact will not cause the housing injection molded part directly opposite it to melt at high temperature due to excessive temperature.
[0018] In a preferred embodiment of this invention, the stationary contact is fixed in the injection-molded housing, and the side of the moving contact is connected to the driving component via a spring.
[0019] In this application, the stationary contact is fixed within the injection-molded housing and will not shift relative to the housing. The side of the moving contact, specifically the side between the first and second ends of the moving contact, is connected to a driving component via a spring, such as an armature. The spring is provided to ensure the resetting of the moving contact. When the coil is energized and generates a magnetic field, the electromagnetic force must overcome the spring force to bring the moving contact into contact with the stationary contact. When the coil is de-energized and no magnetic field is generated, the spring force can quickly reset the moving contact, separating the moving and stationary contacts and thus improving the accuracy of the moving contact position and the coil current correspondence.
[0020] In a preferred embodiment of this invention, the first end of the moving contact is provided with a first contact coating; the end of the stationary contact near the moving contact is provided with a second contact coating.
[0021] When the moving contact and the stationary contact come into contact, they need to conduct electricity to form a closed circuit. Therefore, a first contact coating is applied to the first end of the moving contact, and a second contact coating is applied at the point where the stationary contact and the moving contact come into contact. The materials of the first and second contact coatings can be the same or different, but both must be conductive. Specifically, both the first and second contact coatings are silver-based alloys with a silver content of ≥79%. Silver has good electrical and thermal conductivity and strong oxidation resistance. Using a silver-based alloy as the contact coating ensures effective conduction between the moving and stationary contacts.
[0022] The second objective of this application is to provide a relay, including an assembly structure as described above for preventing moving contacts from sticking together.
[0023] In a preferred embodiment of this utility model, the first end of the moving contact is cylindrical, and a first contact coating is provided on the first end of the moving contact. When the rated current of the relay is greater than or equal to 3A and less than or equal to 10A, the thickness of the first contact coating is greater than or equal to 0.12mm, and the diameter of the first end of the moving contact is greater than or equal to 2.2mm.
[0024] When the rated current of the relay is greater than 10A and less than or equal to 20A, the thickness of the coating of the first contact is greater than or equal to 0.2mm, and the diameter of the first end of the moving contact is greater than or equal to 2.9mm.
[0025] When the rated current of the relay is greater than 20A and less than 40A, the thickness of the coating of the first contact is greater than or equal to 0.25mm, and the diameter of the first end of the moving contact is greater than or equal to 4.3mm.
[0026] When the rated current of the relay is greater than or equal to 40A, the thickness of the coating of the first contact is greater than or equal to 0.3mm, and the diameter of the first end of the moving contact is greater than or equal to 4.5mm.
[0027] The relay prepared in this embodiment passed the current surge resistance test under rated voltage and current conditions, and its performance remained qualified after 100,000 cycles of engagement. This fully demonstrates that the relay structure of this application can effectively avoid abnormal engagement of the electromagnetic relay due to unreasonable heat transfer during engagement.
[0028] The beneficial effects of this utility model are as follows:
[0029] This application provides an assembly structure to prevent moving contacts from sticking together, including a housing injection molded part and a stationary contact and a moving contact located inside the housing injection molded part; a first end of the moving contact is disposed opposite to the stationary contact, and a second end of the moving contact is disposed separately from the housing injection molded part; a driving member is connected to the side of the moving contact; the driving member can drive the moving contact to move towards or away from the stationary contact; a clearance groove is provided inside the housing injection molded part, and the clearance groove is directly opposite the second end of the moving contact. In this application, the moving contact can be moved to a position where it contacts the stationary contact under the drive of the driving component to achieve circuit conduction; or it can be moved to a position where it separates from the stationary contact under the drive of the driving component to achieve circuit disconnection. The first end of the moving contact is arranged opposite to the stationary contact, and the second end of the moving contact faces the housing injection molded part. In this application, a clearance groove is provided in the housing injection molded part facing the second end of the moving contact. In this way, when the moving contact separates from the stationary contact, a sufficient gap can be maintained between the moving contact and the housing injection molded part to prevent the moving contact and the housing injection molded part from sticking together under high current impact, which would affect the normal operation of the relay.
[0030] This application also provides a relay, including the assembly structure described above for preventing the moving contact from sticking. A clearance groove is provided in the injection molded housing part, facing the second end of the moving contact. In this way, when the moving contact is separated from the stationary contact, a sufficient gap can be maintained between the moving contact and the injection molded housing part, so as to prevent the moving contact and the injection molded housing part from sticking together under high current impact, which would affect the normal operation of the relay. Attached Figure Description
[0031] Figure 1 This is a schematic diagram of the structure of the moving contact, stationary contact, and housing injection molded part in the prior art;
[0032] Figure 2 This is a schematic diagram of the structure of a shell injection molded part in the prior art;
[0033] Figure 3 This is a structural schematic diagram of the moving contact, stationary contact, and housing injection molded part of this application;
[0034] Figure 4 This is a schematic diagram showing the dimensions of the moving contact in this application;
[0035] Figure 5 This is a structural schematic diagram of the injection-molded housing part of this application.
[0036] Figure 6 This is a schematic diagram of the structure of the first contact coating and the second contact coating in this application.
[0037] 11. Stationary contact; 111. Second contact coating; 121. First end of moving contact; 122. Second end of moving contact; 123. First contact coating; 13. Spring; 14. Drive component; 21. Housing injection molded part; 22. Alternating groove. Detailed Implementation
[0038] Preferred embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the present invention are shown in the drawings, it should be understood that the present invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present invention will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art.
[0039] The terminology used in this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a,” “the,” and “the” used in this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.
[0040] It should be understood that although the terms "first," "second," "third," etc., may be used in this invention to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this invention, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Thus, features defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.
[0041] Example 1
[0042] like Figures 1-6 As shown, the assembly structure for preventing moving contacts from sticking provided in this application includes a housing injection molded part 21 and a stationary contact 11 and a moving contact located inside the housing injection molded part 21.
[0043] The first end 121 of the moving contact is disposed opposite to the stationary contact 11, and the second end 122 of the moving contact is disposed separately from the housing injection molded part 21; the side of the moving contact is connected to the driving member 14; the driving member 14 can drive the moving contact to move towards or away from the stationary contact 11;
[0044] The housing injection molded part 21 is provided with a clearance groove 22, which is directly opposite the second end 122 of the moving contact.
[0045] This application does not require changing the overall structure of the existing relay. It only requires changing the injection mold during the injection molding process of the housing injection mold 21 to form a relief groove 22 in the integrally molded housing injection mold 21. The relief groove 22 avoids the moving contact, preventing the moving contact and the housing injection mold 21 from deforming and sticking together under high current impact.
[0046] This application solves the problem that, under conditions of high-frequency engagement, high voltage, and high current, the moving and stationary contacts 11 of the electromagnetic relay generate a large amount of heat in a sealed environment, causing the moving contact to directly contact the injection molded base part. This avoids adhesion problems, eliminates potential quality hazards, and improves product reliability.
[0047] In this application, the driving component 14 can be an armature, which is arranged opposite to the iron core in the coil. Depending on whether a magnetic field is generated in the coil, the moving contact moves towards the stationary contact 11 or away from the stationary contact 11.
[0048] In this application, the moving contact can be a cylindrical structure or a cuboid structure. The top and bottom ends of the moving contact are the first end 121 and the second end 122 of the moving contact, respectively. The driving member 14 is connected to the side of the moving contact, for example, it can be connected to the center of the side of the moving contact. When the driving member 14 moves closer to or away from the coil, it can synchronously drive the first end 121 of the moving contact to abut or separate from the stationary contact 11.
[0049] In this application, the moving contact can be moved to a position where it contacts the stationary contact 11 under the drive of the driving member 14, so as to realize circuit conduction; or it can be moved to a position where it separates from the stationary contact 11 under the drive of the driving member 14, so as to realize circuit disconnection. The first end 121 of the moving contact is set opposite to the stationary contact 11, and the second end 122 of the moving contact is directly opposite to the housing injection molded part 21. In this application, a relief groove 22 is provided in the housing injection molded part 21, which is directly opposite to the second end 122 of the moving contact. In this way, when the moving contact is separated from the stationary contact 11, a sufficient gap can be maintained between the moving contact and the housing injection molded part 21, so as to avoid the moving contact and the housing injection molded part 21 sticking together under high current impact, which would affect the normal operation of the relay.
[0050] Example 2
[0051] like Figures 1-6 As shown, the assembly structure for preventing moving contacts from sticking provided in this application includes a housing injection molded part 21 and a stationary contact 11 and a moving contact located inside the housing injection molded part 21.
[0052] The first end 121 of the moving contact is disposed opposite to the stationary contact 11, and the second end 122 of the moving contact is disposed separately from the housing injection molded part 21; the side of the moving contact is connected to the driving member 14; the driving member 14 can drive the moving contact to move towards or away from the stationary contact 11;
[0053] The housing injection molded part 21 is provided with a clearance groove 22, which is directly opposite the second end 122 of the moving contact.
[0054] Furthermore, in the plane parallel to the second end 122 of the moving contact, the cross-sectional area of the clearance groove 22 is greater than the cross-sectional area of the second end 122 of the moving contact.
[0055] In this application, the housing injection molded part 21 refers to the integral structure that wraps around the moving contact and the stationary contact 11. The second end 122 of the moving contact is only adjacent to one plane of the housing injection molded part 21, and the second end 122 of the moving contact and the plane are arranged parallel to each other. In the prior art, there is a certain gap between the second end 122 of the moving contact and the plane, so that the moving contact can move relative to the plane. In this application, an additional clearance groove 22 is provided in the plane, which increases the distance between the second end of the moving contact and the plane, and prevents the moving contact from contacting and sticking to the plane under high current impact. In order to achieve a better clearance effect, the cross-sectional area of the clearance groove 22 is larger than the cross-sectional area of the second end 122 of the moving contact, ensuring that there is sufficient space between the moving contact and the plane, and preventing the second end 122 of the moving contact from contacting the housing injection molded part 21. The application provides a larger relief groove 22, which can also dissipate heat from the moving contact. Since air has a high thermal conductivity, the heat in the moving contact can be dissipated in time through the relief groove 22, preventing the overall temperature of the relay from becoming too high, and also preventing the temperature of the second end 122 of the moving contact from becoming too high, which would cause the housing injection molded part 21 opposite to it to melt at high temperature, resulting in deformation and adhesion.
[0056] Furthermore, the second end 122 of the moving contact is a cuboid, and the clearance groove 22 is a cuboid-shaped groove. In the plane parallel to the second end 122 of the moving contact, the length of the clearance groove 22 is twice the length of the second end 122 of the moving contact; the width of the clearance groove 22 is twice the width of the second end 122 of the moving contact.
[0057] In this application, the second end 122 of the moving contact is set to a cuboid, and correspondingly, the clearance groove 22 is also a cuboid structure. In order to achieve better clearance effect and heat dissipation function, the length and width of the clearance groove 22 are both twice that of the second end 122 of the moving contact. In this way, it can ensure that there is enough space between the second end 122 of the moving contact and the housing injection molded part 21, and also achieve a better heat dissipation effect. At the same time, the larger volume of the clearance groove 22 also helps the housing injection molded part 21 to be demolded, reducing the injection molding difficulty of the housing injection molded part 21.
[0058] Furthermore, the depth of the clearance groove 22 is 0.2-0.5mm.
[0059] Since there is a certain gap between the housing injection molded part 21 and the second end 122 of the moving contact, setting the depth of the clearance groove 22 in the range of 0.2-0.5mm can meet the clearance requirements, the heat dissipation requirements, and the injection molding difficulty of the housing injection molded part 21.
[0060] Furthermore, the vertical distance between the second end 122 of the moving contact and the bottom of the clearance groove 22 is greater than 1 mm.
[0061] Since there is a certain gap between the housing injection molded part 21 and the second end 122 of the moving contact, the depth of the relief groove 22 is set in the range of 0.2-0.5mm. By controlling the relative position between the housing injection molded part 21 and the moving contact, it can be ensured that the vertical distance between the second end 122 of the moving contact and the bottom of the relief groove 22 is greater than 1mm. At this distance, it can be ensured that under high current excitation, the second end 122 of the moving contact will not cause the housing injection molded part 21 directly opposite it to melt at high temperature due to excessive temperature.
[0062] Furthermore, the stationary contact 11 is fixed in the injection-molded housing 21, and the side of the moving contact is connected to the driving component 14 via a spring 13.
[0063] In this application, the stationary contact 11 is fixed in the injection-molded housing 21 and will not be displaced relative to the injection-molded housing 21. The side of the moving contact, that is, the side between the first end 121 and the second end 122 of the moving contact, is connected to the driving member 14 via a spring 13. The driving member 14 is, for example, an armature. The spring 13 is provided to ensure the reset of the moving contact. When the coil is energized and generates a magnetic field, the electromagnetic force needs to overcome the elasticity of the spring 13 to drive the moving contact to abut against the stationary contact 11. When the coil is de-energized and no magnetic field is generated, the elasticity of the spring 13 can drive the moving contact to reset quickly, realizing the separation of the moving contact and the stationary contact 11, thereby improving the accuracy of the position of the moving contact and the corresponding coil current.
[0064] Furthermore, the first end 121 of the moving contact is provided with a first contact coating 123; the end of the stationary contact 11 near the moving contact is provided with a second contact coating 111.
[0065] When the moving contact and the stationary contact 11 come into contact, they need to conduct to form a closed circuit. Therefore, a first contact coating 123 is provided at the first end 121 of the moving contact, and a second contact coating 111 is provided at the contact position between the stationary contact 11 and the moving contact. The materials of the first contact coating 123 and the second contact coating 111 can be the same or different, but both need to be conductive. Specifically, both the first contact coating 123 and the second contact coating 111 are silver-based alloys with a silver content of ≥79%. Silver has good electrical and thermal conductivity and strong oxidation resistance. Using a silver-based alloy as the contact coating can ensure effective conduction between the moving contact and the stationary contact 11.
[0066] Example 3
[0067] like Figures 1-6 As shown, the assembly structure for preventing moving contacts from sticking provided in this application includes a housing injection molded part 21 and a stationary contact 11 and a moving contact located inside the housing injection molded part 21.
[0068] The first end 121 of the moving contact is disposed opposite to the stationary contact 11, and the second end 122 of the moving contact is disposed separately from the housing injection molded part 21; a driving member 14 is connected to the side of the moving contact; the driving member 14 can drive the moving contact to move closer to or further away from the stationary contact 11; a clearance groove 22 is provided in the housing injection molded part 21, and the clearance groove 22 is directly opposite the second end 122 of the moving contact. In the plane parallel to the second end 122 of the moving contact, the cross-sectional area of the clearance groove 22 is larger than the cross-sectional area of the second end 122 of the moving contact.
[0069] The second end 122 of the moving contact is a cylindrical structure, and the clearance groove 22 is also a cylinder. In a plane parallel to the second end 122 of the moving contact, the diameter of the clearance groove 22 is twice the diameter of the second end 122 of the moving contact. Figure 4 As shown, the diameter of the second end 122 of the moving contact is d, and the diameter of the clearance groove 22 is 2d. The center of the clearance groove 22 and the center of the second end 122 of the moving contact coincide in the vertical direction.
[0070] The depth of the clearance groove 22 is h2, which can be any value within the range of 0.2-0.5mm. The distance between the second end 122 of the moving contact and the bottom of the clearance groove 22 is h1, which needs to be greater than 1mm. Since there is a certain gap between the housing injection molded part 21 and the second end 122 of the moving contact, by setting the depth of the clearance groove 22 within the range of 0.2-0.5mm, and by controlling the relative position between the housing injection molded part 21 and the moving contact, it can be ensured that the vertical distance between the second end 122 of the moving contact and the bottom of the clearance groove 22 is greater than 1mm. At this distance, it can be ensured that under high current excitation, the second end 122 of the moving contact will not cause the housing injection molded part 21 directly opposite it to melt due to excessive temperature.
[0071] The diameter of the first end 121 of the moving contact is D, and the first end 121 of the moving contact is coated with a first contact coating 123, the thickness of which is h3. The first contact coating 123 is a silver-based alloy, in which the silver content is greater than or equal to 79%. Silver has good electrical and thermal conductivity and strong oxidation resistance. Using a silver-based alloy as the contact coating ensures effective conductivity between the moving contact and the stationary contact 11. The diameter D of the first end of the moving contact and the thickness h3 of the first contact coating 123 satisfy the following relationship:
[0072] When the rated current of the relay is less than 3A, the thickness h3 of the coating 123 of the first contact can be set arbitrarily, and the diameter D of the first end 121 of the moving contact can be set arbitrarily.
[0073] When the rated current of the relay is greater than or equal to 3A and less than or equal to 10A, the thickness h3 of the coating 123 of the first contact is greater than or equal to 0.12mm, and the diameter D of the first end 121 of the moving contact is greater than or equal to 2.2mm.
[0074] When the rated current of the relay is greater than 10A and less than or equal to 20A, the thickness h3 of the coating 123 of the first contact is greater than or equal to 0.2mm, and the diameter D of the first end 121 of the moving contact is greater than or equal to 2.9mm.
[0075] When the rated current of the relay is greater than 20A and less than 40A, the thickness h3 of the coating 123 of the first contact is greater than or equal to 0.25mm, and the diameter D of the first end 121 of the moving contact is greater than or equal to 4.3mm.
[0076] When the rated current of the relay is greater than or equal to 40A, the thickness h3 of the coating 123 of the first contact is greater than or equal to 0.3mm, and the diameter D of the first end 121 of the moving contact is greater than or equal to 4.5mm.
[0077] like Figure 3As shown, in this application, the side of the moving contact is connected to the driving member 14 via a spring 13. The side of the moving contact, that is, the side between the first end 121 and the second end 122 of the moving contact, is connected to the driving member 14 via a spring 13. The driving member 14 is, for example, an armature. The spring 13 is provided to ensure the reset of the moving contact. When the coil is energized and generates a magnetic field, the electromagnetic force needs to overcome the elastic force of the spring 13 to drive the moving contact to abut against the stationary contact 11. When the coil is de-energized and no magnetic field is generated, the elastic force of the spring 13 can drive the moving contact to reset quickly, thereby separating the moving contact and the stationary contact 11 and improving the accuracy of the position of the moving contact and the corresponding coil current.
[0078] In this application, the stationary contact 11 is fixed in the housing injection molded part 21 and will not be displaced relative to the housing injection molded part 21. The end of the stationary contact 11 near the moving contact is coated with a second contact coating 111, and the material of the second contact coating 111 is the same as that of the first contact coating 123.
[0079] In this application, when the moving contact is far from the stationary contact 11, the minimum distance between the first end 121 of the moving contact and the stationary contact 11 is 0.18-0.24 mm. This distance range is also the gap between the armature and the iron core after the coil is energized and the contacts are attracted. This ensures that the electromagnetic relay coil is energized and confirms the reliability of the contact. It avoids unreliable contact caused by insufficient contact pressure when the moving contact and the stationary contact 11 are in contact.
[0080] In this application, the housing injection molded part 21 is made of a high-temperature resistant material, such as PBT, with a heat distortion temperature of about 250°C.
[0081] Example 4
[0082] This application also provides a relay, including an assembly structure for preventing moving contacts from sticking as described above, and further including a coil and an iron core, wherein the coil is wound around the outside of the iron core, one end of the iron core is disposed opposite to the armature, the armature is connected to the moving contact through a spring 13, the first end 121 of the moving contact is disposed opposite to the stationary contact 11, and a clearance groove 22 is provided in the housing injection molded part 21, the clearance groove 22 being directly opposite to the second end 122 of the moving contact.
[0083] If the diameter of the second end 122 of the moving contact is d, then the diameter of the clearance groove 22 is 2d, and the center of the clearance groove 22 and the center of the second end 122 of the moving contact coincide in the vertical direction.
[0084] The depth of the clearance groove 22 is h2, which is any value within the range of 0.2-0.5 mm. The distance between the second end 122 of the moving contact and the bottom of the clearance groove 22 is h1, which needs to be greater than 1 mm. The diameter of the first end 121 of the moving contact is D, and the first end 121 of the moving contact is coated with a first contact coating 123, the thickness of which is h3. The first contact coating 123 is a silver-based alloy, and the silver content in the silver-based alloy is greater than or equal to 79%. The diameter D of the first end of the moving contact and the thickness h3 of the first contact coating 123 satisfy the following relationship:
[0085] When the rated current of the relay is less than 3A, the thickness h3 of the coating 123 of the first contact can be set arbitrarily, and the diameter D of the first end 121 of the moving contact can be set arbitrarily.
[0086] When the rated current of the relay is greater than or equal to 3A and less than or equal to 10A, the thickness h3 of the coating 123 of the first contact is greater than or equal to 0.12mm, and the diameter D of the first end 121 of the moving contact is greater than or equal to 2.2mm.
[0087] When the rated current of the relay is greater than 10A and less than or equal to 20A, the thickness h3 of the coating 123 of the first contact is greater than or equal to 0.2mm, and the diameter D of the first end 121 of the moving contact is greater than or equal to 2.9mm.
[0088] When the rated current of the relay is greater than 20A and less than 40A, the thickness h3 of the coating 123 of the first contact is greater than or equal to 0.25mm, and the diameter D of the first end 121 of the moving contact is greater than or equal to 4.3mm.
[0089] When the rated current of the relay is greater than or equal to 40A, the thickness h3 of the coating 123 of the first contact is greater than or equal to 0.3mm, and the diameter D of the first end 121 of the moving contact is greater than or equal to 4.5mm.
[0090] The stationary contact 11 is coated with a second contact coating 111 at the end near the moving contact. The material of the second contact coating 111 is the same as that of the first contact coating 123.
[0091] The housing injection molded part 21 is made of high temperature resistant materials such as PBT, and its heat distortion temperature is about 250℃.
[0092] The relay prepared in this embodiment passed the current surge resistance test under rated voltage and current conditions, and its performance remained qualified after 100,000 cycles of engagement. This fully demonstrates that the relay structure of this application can effectively avoid abnormal engagement of the electromagnetic relay due to unreasonable heat transfer during engagement.
[0093] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings. In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms 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 on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.
[0094] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.
[0095] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this application.
[0096] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. An assembly structure for preventing moving contacts from sticking together, characterized in that, Includes a housing injection molded part (21) and stationary contacts (11) and moving contacts located inside the housing injection molded part (21); The first end (121) of the moving contact is disposed opposite to the stationary contact (11), and the second end (122) of the moving contact is disposed separately from the housing injection molded part (21); the side of the moving contact is connected to a driving member (14); the driving member (14) can drive the moving contact to move towards or away from the stationary contact (11); The housing injection molding part (21) is provided with a clearance groove (22), which is directly opposite the second end (122) of the moving contact.
2. The assembly structure for preventing moving contacts from sticking according to claim 1, characterized in that, In the plane parallel to the second end (122) of the moving contact, the cross-sectional area of the clearance groove (22) is greater than the cross-sectional area of the second end (122) of the moving contact.
3. The assembly structure for preventing moving contacts from sticking according to claim 1, characterized in that, The second end (122) of the moving contact is a cuboid, and the clearance groove (22) is a cuboid-shaped groove. In the plane parallel to the second end (122) of the moving contact, the length of the clearance groove (22) is twice the length of the second end (122) of the moving contact; the width of the clearance groove (22) is twice the width of the second end (122) of the moving contact.
4. The assembly structure for preventing moving contacts from sticking according to claim 1, characterized in that, The depth of the clearance groove (22) is 0.2-0.5 mm.
5. The assembly structure for preventing moving contacts from sticking according to claim 1, characterized in that, The vertical distance between the second end (122) of the moving contact and the bottom of the clearance groove (22) is greater than 1 mm.
6. The assembly structure for preventing moving contacts from sticking according to claim 1, characterized in that, The stationary contact (11) is fixed in the injection molded housing (21), and the side of the moving contact is connected to the driving component (14) through a spring piece (13).
7. The assembly structure for preventing moving contacts from sticking according to claim 1, characterized in that, The first end (121) of the moving contact is provided with a first contact coating (123); the end of the stationary contact (11) near the moving contact is provided with a second contact coating (111).
8. A relay, characterized in that, The assembly structure for preventing moving contacts from sticking, as described in any one of claims 1-7.
9. A relay according to claim 8, characterized in that, The first end (121) of the moving contact is cylindrical, and the first end (121) of the moving contact is provided with a first contact coating (123). When the rated current of the relay is greater than or equal to 3A and less than or equal to 10A, the thickness of the first contact coating (123) is greater than or equal to 0.12mm, and the diameter of the first end (121) of the moving contact is greater than or equal to 2.2mm. When the rated current of the relay is greater than 10A and less than or equal to 20A, the thickness of the coating (123) of the first contact is greater than or equal to 0.2mm, and the diameter of the first end (121) of the moving contact is greater than or equal to 2.9mm. When the rated current of the relay is greater than 20A and less than 40A, the thickness of the coating (123) of the first contact is greater than or equal to 0.25mm, and the diameter of the first end (121) of the moving contact is greater than or equal to 4.3mm. When the rated current of the relay is greater than or equal to 40A, the thickness of the coating (123) of the first contact is greater than or equal to 0.3mm, and the diameter of the first end (121) of the moving contact is greater than or equal to 4.5mm.