Metal oxide varistor with positioning features
By forming through-holes aligned with conductive terminals in the dielectric coating of the metal oxide varistor, the problem of inaccurate positioning in the prior art is solved, achieving a more stable electrical connection and installation.
Patent Information
- Application Number
- CN202410580949.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-10
- Publication Date
- 2025-11-11
AI Technical Summary
When installing existing metal oxide varistors in surge protectors, it is difficult to achieve convenient, safe, and precise positioning, which can lead to terminal tilting or loosening and affect the reliability of electrical connections.
Multiple through-holes aligned with the conductive terminals are formed in the dielectric coating of the metal oxide varistor to ensure that the dielectric coating thickness matches the terminal thickness. The depth of the positioning holes is increased to facilitate fixation using retaining posts or stops, ensuring correct position and orientation.
This improves the installation stability and reliability of metal oxide varistors in surge protectors, reduces the risk of terminal damage and positional misalignment, and ensures the accuracy of electrical connections.
Smart Images
Figure CN120933010A_ABST
Abstract
Description
Technical Field
[0001] This disclosure generally relates to the field of circuit protection devices. More specifically, this disclosure relates to metal oxide varistors having structural features that facilitate precise positioning within surge protectors. Background Technology
[0002] Metal oxide varistors (MOVs) play a crucial role in surge protection devices (SPDs) by rapidly responding to transient voltage spikes. These spikes (typically caused by lightning strikes or power surges) can damage sensitive electronic equipment. MOVs are semiconductors with nonlinear voltage-current characteristics, meaning their resistance decreases as the voltage across them increases. In an SPD, the MOV is connected in parallel with the equipment to be protected. During normal operation, the MOV has high resistance, allowing only negligible current to pass through. However, when a surge occurs, the voltage across the MOV increases rapidly, causing it to conduct significantly, diverting excess current away from the protected equipment and dissipating the surge energy as heat. This action effectively clamps the voltage to a safe level, protecting the connected equipment from damage.
[0003] A typical MOV comprises an MOV chip formed from zinc oxide grains combined with other metal oxides. The MOV chip has metal electrodes on opposite sides, and conductive terminals are attached to each electrode to facilitate electrical connection of the MOV within a circuit (e.g., within an SPD). A conformal dielectric coating, typically formed of a polymer, surrounds portions of the MOV chip, electrodes, and terminals to provide insulation and protection against environmental factors.
[0004] When an MOV is mounted in an SPD, it is important to properly position (i.e., place and orient) the MOV to ensure proper electrical connection within the SPD. Various methods have been developed to aid in positioning the MOV during mounting. One such method involves simply placing the MOV into a similarly sized / shaped slot or cavity within the SPD, thereby constraining the sides or edges of the MOV to hold it in the desired position and orientation. This method can be unreliable because the thickness of the dielectric coating on the MOV is often uneven, causing the MOV chip and terminals to tilt after mounting. Another method for aiding in positioning the MOV within the SPD involves forming multiple small locating holes in the dielectric coating on at least one side of the MOV. When the MOV is mounted within the SPD, corresponding retaining posts or detents can engage the locating holes, thereby holding the MOV in the desired position and orientation. This method is also associated with certain defects. For example, when locating holes are formed in the dielectric coating of the MOV, it is possible that the MOV's terminals (which are typically located near the locating holes) may be damaged. Furthermore, because the dielectric coating is typically very thin (e.g., about 0.5 mm thick), the retaining post or stop of the SPD may have difficulty securing itself to the edge of the dielectric coating that borders the positioning hole. As a result, the MOV may be loosely held in place and may easily slip out or move out of its desired position and orientation.
[0005] In view of the above, it is desirable to provide an MOV that is easy, safe, and precisely positioned when installed in an SPD. It is precisely because of these and other considerations that the current improvements may be useful. Summary of the Invention
[0006] The present invention is provided to introduce, in a simplified form, the selection of concepts further described below in the detailed description. The present invention is not intended to identify key or essential features of the claimed subject matter, nor is it intended to assist in determining the scope of the claimed subject matter.
[0007] A metal oxide varistor (MOV) according to an embodiment of the present disclosure may include an MOV chip having a first electrode and a second electrode disposed on opposite sides thereof; a first terminal connected to the first electrode and a second terminal connected to the second electrode, the first terminal having a plurality of through-holes formed therethrough; and a dielectric coating covering the MOV chip, the first electrode and the second electrode, and portions of the first terminal and the second terminal, the dielectric coating having a plurality of through-holes formed therethrough, wherein each of the plurality of through-holes in the dielectric coating is aligned with one of the plurality of through-holes in the first terminal.
[0008] A method of manufacturing an MOV according to embodiments of the present disclosure may include providing an MOV chip having a first electrode and a second electrode disposed on opposite sides thereof; connecting a first terminal to the first electrode and a second terminal to the second electrode, the first terminal having a plurality of through-holes formed therethrough; applying a dielectric coating to the MOV chip, the first electrode and the second electrode, and portions of the first terminal and the second terminal; and forming a plurality of through-holes in the dielectric coating, wherein each of the plurality of through-holes in the dielectric coating is aligned with one of the plurality of through-holes in the first terminal. Attached Figure Description
[0009] Various embodiments of the present disclosure will now be described by way of example with reference to the accompanying drawings, in which:
[0010] Figure 1A This is a perspective view of an MOV according to an embodiment of the present disclosure;
[0011] Figure 1B It is a diagram. Figure 1A An exploded view of the MOV;
[0012] Figure 2 This is a flowchart illustrating a method for manufacturing an MOV according to an embodiment of the present disclosure. Detailed Implementation
[0013] As used herein, elements or operations described in the singular and beginning with the words “a” or “an” should be understood to include multiple elements or operations unless otherwise indicated. Furthermore, various embodiments herein have been described in the context of one or more elements or components. Elements or components may include any structure arranged to perform certain operations. Although embodiments may be described by way of example with a limited number of elements in a particular topology, the embodiment may include more or fewer elements in alternative topologies as expected for a given implementation. Note that any reference to “an embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The phrases “in one embodiment,” “in some embodiments,” and “in various embodiments” appearing in various places in the specification do not necessarily refer to the same embodiment.
[0014] Embodiments of metal oxide varistors (MOVs) according to the present disclosure and methods of manufacturing MOVs will now be described more fully with reference to the accompanying drawings, in which preferred embodiments of the present disclosure are presented. However, MOVs and manufacturing methods can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will convey certain aspects of MOVs and manufacturing methods to those skilled in the art. In the drawings, unless otherwise stated, similar figures always refer to similar elements.
[0015] refer to Figure 1A and Figure 1B The illustration shows a perspective view and an exploded view of a metal oxide varistor (MOV) 10 according to the present disclosure (for clarity, from...). Figure 1B The dielectric coating 22 of MOV 10 described below is omitted. For convenience and clarity, terms such as "top," "bottom," "above," "below," "under," "over," etc., are used herein to describe the relative placement and orientation of the various components of MOV 10, each component relating to, as shown in, the dielectric coating 22 of MOV 10 described below. Figure 1A and Figure 1B The geometry and orientation of MOV 10 appearing in the text. The terminology will include specifically mentioned words, their derivatives, and words of similar meaning.
[0016] refer to Figure 1B The MOV 10 may include an MOV chip 12, which has a first electrode and a second electrode 14a, 14b disposed on opposite sides thereof (the second electrode 14b is not present). Figure 1B (As shown in the view, but substantially the same as the first electrode 14a). In various embodiments, the MOV chip 10 may be formed from zinc oxide grains combined with other metal oxides. This disclosure is not limited in this respect. The first and second electrodes 14a, 14b may be formed from any suitable conductive material, including but not limited to copper, copper alloys, aluminum, aluminum coated with copper, silver, tin, nickel, etc. The first and second electrodes 14a, 14b may be attached to the MOV chip 12 by cold pressing, solder, conductive adhesive, etc., or may be deposited on the MOV chip by a sputtering deposition process. This disclosure is not limited in this respect. The MOV chip 12 and the first and second electrodes 14a, 14b are depicted in a generally rectangular shape, but this is not critical. It is conceivable that one or more of the MOV chip 12 and the first and second electrodes 14a, 14b may have different shapes, such as circular, triangular, irregular shapes, etc., without departing from the scope of this disclosure.
[0017] The MOV 10 may further include conductive first and second terminals 15 and 16 connected to the first and second electrodes 14a and 14b. The first and second terminals 15 and 16 may include corresponding contact portions 15a and 16a mechanically connected to the first and second electrodes 14a and 14b (e.g., via brazing, soldering, conductive adhesive, etc.) and corresponding lead portions 15b and 16b extending from the contact portions 15a and 16a to facilitate electrical connection of the MOV 10 within a circuit. The contact portions 15a and 16a may be as follows: Figure 1B The annular shape shown may also be used, or any other suitable shape may be used to provide robust mechanical and electrical contact with the first and second electrodes 14a, 14b. In various non-limiting embodiments, the first and second terminals 15, 16 may be formed of copper, tin, silver, etc. This disclosure is not limited in this respect.
[0018] The contact portion 15a of the first terminal 15 may have a plurality of through holes 20 formed therethrough. The through holes 20 are depicted as circular, but this is not critical. The through holes 20 may have any suitable shape, including but not limited to rectangular, triangular, irregular shapes, etc. The contact portion 15a is shown as having three through holes 20 formed therethrough, but this is not intended to be limiting. In various embodiments, the contact portion 15a may have as few as two through holes 20 formed therethrough. In other embodiments, the contact portion 15a may have more than three through holes 20 formed therethrough. Furthermore, while only the contact portion 15a of the first terminal 15 is provided with through holes 20, alternative embodiments of this disclosure in which the contact portion 16a of the second terminal 16 is also provided with through holes 20 are conceivable.
[0019] refer to Figure 1AThe MOV 10 may further include a dielectric coating 22 covering portions of the MOV chip 12, the first and second electrodes 14a, 14b, and the first and second terminals 15, 16. The dielectric coating 22 protects the covered components of the MOV 10 from environmental factors and prevents electrical short circuits between the MOV 10 and surrounding circuit components. In various embodiments, the dielectric coating 22 may be formed of a dielectric polymer or other dielectric material suitable for conformal application to the underlying components of the MOV 10. The dielectric coating 22 may have a plurality of through-holes 24 formed therein, which may be aligned with through-holes 20 formed in the contact portion 15a of the first terminal 15 and may have the same overall size and shape (e.g., the same diameter) as the through-holes 20 formed in the contact portion 15a of the first terminal 15. In particular, the edges of the through-holes 24 in the dielectric coating 22 may be aligned with the edges of the corresponding underlying through-holes 20 in the contact portion 15a of the first terminal 15. Through-hole 24 may be formed in dielectric coating 22 after dielectric coating 22 is applied to the component below MOV 10, as further described below.
[0020] Each through-hole 24 in the dielectric coating 22 and its corresponding underlying through-hole 20 in the contact portion 15a of the first terminal 15 can together form a positioning hole 30 in the MOV 10. When the MOV 10 is installed within a surge protector, the positioning hole 30 can receive a corresponding retaining post or stop (e.g., extending from an internal compartment of the SPD adapted to hold the MOV 10) to secure the MOV 10 in a desired position and orientation. Each positioning hole 30 can have a depth equal to the sum of the thicknesses of the dielectric coating 22 and the contact portion 15a of the first terminal 15. In various embodiments, each positioning hole 30 can have a depth ranging from about 1 mm to about 2 mm. This disclosure is not limited in this respect. This contrasts with prior art MOVs having positioning holes that extend only through the dielectric coating, where such positioning holes have a depth equal only to the thickness of the dielectric coating (e.g., about 0.5 mm). Therefore, the positioning holes of the MOV 10 of this disclosure are significantly deeper than those of prior art MOVs, and thus allow the retaining post or stop of the SPD to obtain a more secure and robust grip on the MOV 10 compared to prior art MOVs. Consequently, the MOV 10 of this disclosure can be positioned more accurately and precisely within the SPD compared to prior art MOVs, and is less prone to displacement or sliding after installation in the SPD.
[0021] refer to Figure 2 A flowchart illustrating an exemplary method for manufacturing the aforementioned MOV 10 according to this disclosure is shown. Now, in conjunction with... Figure 1A and Figure 1BThe method is illustrated in the diagram of MOV 10 presented in the figure.
[0022] exist Figure 2 In block 100 of the method shown, an MOV chip 12 may be provided, and may have a first electrode and a second electrode 14a, 14b disposed on opposite sides thereof. The MOV chip 10 may be formed from zinc oxide grains combined with other metal oxides. This disclosure is not limited in this respect. The first electrode and the second electrode 14a, 14b may be formed from any suitable conductive material, including but not limited to copper, copper alloys, aluminum, aluminum coated with copper, silver, tin, nickel, etc. The first electrode and the second electrode 14a, 14b may be attached to the MOV chip 12 by cold pressing, solder, conductive adhesive, etc., or may be deposited on the MOV chip by a sputtering deposition process. This disclosure is not limited in this respect.
[0023] In block 110 of the method, conductive first and second terminals 15, 16 can be connected to first and second electrodes 14a, 14b, respectively. Specifically, contact portions 15a, 16a of the first and second terminals 15, 16 can be mechanically connected to the first and second electrodes 14a, 14b, such as via brazing, welding, conductive adhesive, etc., wherein corresponding lead portions 15b, 16b of the first and second terminals 15, 16 extend from contact portions 15a, 16a. In various non-limiting embodiments, the first and second terminals 15, 16 can be formed of copper, tin, silver, etc. This disclosure is not limited in this respect. As described above, the contact portion 15a of the first terminal 15 can have a plurality of through holes 20 formed therethrough. The through holes 20 can be formed in the contact portion 15a by cutting, drilling, punching, etching, etc. This disclosure is not limited in this respect.
[0024] In block 120 of the method, a dielectric coating 22 may be applied to portions of the MOV chip 12, the first and second electrodes 14a, 14b, and the first and second terminals 15, 16. Lead portions 15b, 16b of the first and second terminals 15, 16 may extend beyond the dielectric coating 22 to facilitate electrical connection of the MOV 10 within a circuit. As described above, the dielectric coating 22 may be formed of a dielectric polymer or other dielectric material suitable for conformal application to the underlying components of the MOV 10. The dielectric coating 22 may be applied to the underlying components using any suitable method (including but not limited to dipping, spraying, etc.). In block 130 of the method, a via 24 may be formed in the dielectric coating 22, such as by cutting (e.g., laser cutting), drilling, etching, etc. As described above, the via 24 may be aligned with an underlying via 20 formed in the contact portion 15a of the first terminal 15 and may have the same overall size and shape as the underlying via 20 formed in the contact portion 15a of the first terminal 15.
[0025] As used herein, elements or steps described in the singular and beginning with the words “a” or “an” should be understood to not exclude plural elements or steps unless such exclusion is explicitly stated. Furthermore, references to “one embodiment” in this disclosure are not intended to be construed as excluding the existence of additional embodiments that also include the described features.
[0026] While this disclosure references certain embodiments, numerous modifications, alterations, and variations of the described embodiments are possible without departing from the field and scope of this disclosure as defined by the appended claims. Therefore, this disclosure is intended to be limited to the described embodiments, but rather to have the full scope defined by the language of the following claims and their equivalents.
Claims
1. A metal oxide varistor (MOV), comprising: MOV chip, the MOV chip having a first electrode and a second electrode disposed on opposite sides thereof; A first terminal connected to the first electrode and a second terminal connected to the second electrode, wherein the first terminal has a plurality of through holes formed therethrough; and A dielectric coating covering portions of the MOV chip, the first electrode and the second electrode, and the first terminal and the second terminal, the dielectric coating having a plurality of through-holes formed therethrough, wherein each of the plurality of through-holes in the dielectric coating is aligned with one of the plurality of through-holes in the first terminal.
2. The MOV according to claim 1, wherein, The first terminal includes a contact portion and a lead portion extending from the contact portion, wherein the contact portion is mechanically connected to the first electrode, and wherein the lead portion extends beyond the dielectric coating and facilitates the electrical connection of the MOV within the circuit, wherein a plurality of through-holes in the first terminal are formed in the contact portion.
3. The MOV according to claim 3, wherein, The contact portion of the first terminal defines a circuit.
4. The MOV according to claim 1, wherein, Each through-hole in the dielectric coating and the corresponding lower through-hole in the first terminal together define a positioning hole, the positioning hole having a depth equal to the sum of the thickness of the dielectric coating and the thickness of the first terminal.
5. The MOV according to claim 1, wherein, The size and shape of each via in the dielectric coating are the same as the size and shape of the corresponding via in the first terminal.
6. The MOV according to claim 1, wherein, Each positioning hole has a depth ranging from 1 mm to 2 mm.
7. The MOV according to claim 1, wherein, The MOV includes at least three positioning holes in total.
8. The MOV according to claim 1, wherein, Each via in the dielectric coating has an edge aligned with the edge of the corresponding lower via in the first terminal.
9. The MOV according to claim 1, wherein, The MOV chip is formed from zinc oxide grains combined with other metal oxides.
10. The MOV according to claim 1, wherein, The dielectric coating is formed from a dielectric polymer.
11. A method for manufacturing a metal oxide varistor (MOV), the method comprising: An MOV chip is provided, the MOV chip having a first electrode and a second electrode disposed on opposite sides thereof; A first terminal is connected to the first electrode, and a second terminal is connected to the second electrode, wherein the first terminal has a plurality of through holes formed therethrough; A dielectric coating is applied to the MOV chip, the first electrode and the second electrode, and portions of the first terminal and the second terminal; and A plurality of through-holes are formed in the dielectric coating, wherein each of the plurality of through-holes in the dielectric coating is aligned with one of the plurality of through-holes in the first terminal.
12. The method according to claim 11, wherein, The first terminal includes a contact portion and a lead portion extending from the contact portion, wherein the contact portion is mechanically connected to the first electrode, and wherein the lead portion extends beyond the dielectric coating and facilitates the electrical connection of the MOV within the circuit, wherein a plurality of through-holes in the first terminal are formed in the contact portion.
13. The method according to claim 12, wherein, The contact portion of the first terminal defines a circuit.
14. The method according to claim 11, wherein, Each through-hole in the dielectric coating and the corresponding lower through-hole in the first terminal together define a positioning hole, the positioning hole having a depth equal to the sum of the thickness of the dielectric coating and the thickness of the first terminal.
15. The method according to claim 11, wherein, The size and shape of each via in the dielectric coating are the same as the size and shape of the corresponding via in the first terminal.
16. The method according to claim 11, wherein, Each positioning hole has a depth ranging from 1 mm to 2 mm.
17. The method according to claim 11, wherein, The MOV includes at least three positioning holes in total.
18. The method according to claim 11, wherein, Each via in the dielectric coating has an edge aligned with the edge of the corresponding lower via in the first terminal.
19. The method according to claim 11, wherein, The MOV chip is formed from zinc oxide grains combined with other metal oxides.
20. The method according to claim 11, wherein, The dielectric coating is formed from a dielectric polymer.