Flame retardant protective film capacitor

Abstract

The utility model discloses a kind of flame-retardant protective film capacitors, it is related to film capacitor technical field, including flame-retardant shell, the inside filling of flame-retardant shell is provided with flame-retardant potting adhesive, the inside of flame-retardant potting adhesive is provided with the capacitor component for capacitor energy storage, the utility model solves the problem that the existing film capacitor flame-retardant performance is low, not applicable to the scene of high fireproof grade requirement, the utility model is set through flame-retardant shell, plastic sleeve shell and plastic cover are mutually clamped, form full-sealing protective sleeve, mica coating layer is set in the outer layer of plastic sleeve shell and plastic cover, the flame-retardant mica powder used by mica coating layer is inorganic silicate mineral itself, melting point is high, does not burn, does not release toxic gas, dense insulating layer is formed under high temperature, with good external flame-retardant effect, the setting of flame-retardant potting adhesive, flame-retardant potting adhesive uses polyurethane material, inert gas, such as carbon dioxide, nitrogen etc, is released when burning, oxygen is isolated.

Description

Technical Field

[0001] This utility model relates to the field of thin film capacitor technology, specifically a flame-retardant and protective thin film capacitor. Background Technology

[0002] Film capacitors are capacitors that use metal foil as electrodes, which are overlapped at both ends with plastic films such as polyethylene, polypropylene, polystyrene or polycarbonate, and then wound into a cylindrical shape.

[0003] The film capacitor authorized by CN108780700B includes a component body formed by winding or stacking a metallized film, a P-electrode and an N-electrode formed on both ends of the component body; a P-electrode busbar and an N-electrode busbar (30) respectively connected to the P-electrode and the N-electrode; and a conductive covering portion that covers the outer periphery of the capacitor element when separated from at least one of the P-electrode and the N-electrode. Existing film capacitors are directly wrapped with plastic film for insulation and protection, which has low flame retardant performance and is not suitable for scenarios with high fire protection requirements.

[0004] To address the aforementioned issues, a flame-retardant and protective film capacitor is proposed. Utility Model Content

[0005] The purpose of this invention is to provide a flame-retardant and protective film capacitor, which solves the problem that existing film capacitors, which are directly wrapped with plastic film for insulation and protection, have low flame-retardant performance and are not suitable for scenarios with high fire protection requirements.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a flame-retardant protective film capacitor, comprising a flame-retardant shell, wherein the interior of the flame-retardant shell is filled with a flame-retardant potting compound, and a capacitor assembly for energy storage is disposed inside the flame-retardant potting compound. The flame-retardant shell includes a plastic sleeve and a plastic cover that are interlocked with each other, and a mica coating layer is disposed on the outer side of the plastic sleeve and the plastic cover. The flame-retardant potting compound between the flame-retardant shell and the capacitor assembly is made of polyurethane material.

[0007] Preferably, a slot is provided on one side of the lower end of the plastic sleeve, and a locking block is provided on one side of the lower end of the plastic cover.

[0008] Preferably, the mica coating layer is formed by spraying a fire-retardant coating made of mica powder and flame retardant.

[0009] Preferably, the capacitor assembly includes a dielectric film and an inner electrode metal foil that are bonded together, and the dielectric film and the inner electrode metal foil are stacked and wound from the inside out.

[0010] Preferably, the capacitor assembly further includes an outer electrode block covering both sides of the inner electrode metal foil.

[0011] Preferably, an external pin is welded to one side of the external electrode block, and two sets of external pins are provided.

[0012] Preferably, the external pins are disposed through the plastic sleeve cover.

[0013] Preferably, the dielectric film and the inner electrode metal foil are wound to form a flat cylindrical core.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. This utility model provides a flame-retardant protective film capacitor. Through the setting of a flame-retardant shell, the plastic shell and plastic cover are interlocked to form a fully sealed protective sleeve. The mica coating layer is set on the outer layer of the plastic shell and plastic cover. The flame-retardant mica powder used in the mica coating layer is itself an inorganic silicate mineral with a high melting point. It does not burn or release toxic gases. It forms a dense insulating layer at high temperatures and has a good external flame-retardant effect. This initially solves the problem that existing film capacitors directly wrap plastic film for insulation and protection, resulting in low flame-retardant performance and unsuitability for scenarios with high fire protection requirements.

[0015] 2. The flame-retardant protective film capacitor provided by this utility model uses a flame-retardant potting compound made of polyurethane. When burning, the polyurethane releases inert gases such as carbon dioxide and nitrogen, which isolate oxygen and do not affect the leakage current index of the capacitor. This ensures that the core electrical performance of the capacitor, such as capacitance, loss tangent, and withstand voltage, is not damaged after replacement. This solves the problem that existing film capacitors, which are directly wrapped with plastic film for insulation and protection, have low flame-retardant performance and are not suitable for scenarios with high fire protection requirements. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram showing the disassembled structure of the flame-retardant shell of this utility model; Figure 3 This is a schematic diagram of the overall split structure of this utility model; Figure 4 This is a schematic diagram of the disassembled structure of the capacitor assembly of this utility model; Figure 5 This is a side view of the capacitor assembly of this utility model.

[0017] In the diagram: 1. Flame-retardant outer shell; 11. Plastic sleeve; 111. Slot; 12. Plastic cover; 121. Slot; 13. Mica coating layer; 2. Flame-retardant potting compound; 3. Capacitor assembly; 31. Dielectric film; 32. Inner electrode metal foil; 33. Outer electrode block; 34. External pin. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] To further understand the content of this utility model, a detailed description of this utility model will be provided in conjunction with the accompanying drawings.

[0020] Combination Figure 1 This utility model discloses a flame-retardant protective film capacitor, comprising a flame-retardant shell 1, the interior of which is filled with flame-retardant potting compound 2, and the interior of which is a capacitor assembly 3 for energy storage. The flame-retardant shell 1 includes a plastic sleeve 11 and a plastic cover 12 that are interlocked. The outer sides of the plastic sleeve 11 and the plastic cover 12 are provided with a mica coating layer 13. The flame-retardant potting compound 2 between the flame-retardant shell 1 and the capacitor assembly 3 is made of polyurethane.

[0021] Specifically, the plastic shell 11 and the plastic cover 12 are interlocked to form a fully sealed protective sleeve. The mica coating layer 13 is applied to the outer layer of the plastic shell 11 and the plastic cover 12. The flame-retardant mica powder used in the mica coating layer 13 is an inorganic silicate mineral with a high melting point. It does not burn or release toxic gases and forms a dense insulating layer at high temperatures, providing excellent external flame retardant effect. The internal flame-retardant potting compound 2 is made of polyurethane material, which releases inert gases such as carbon dioxide and nitrogen when burning, thus isolating oxygen and not affecting the leakage current index of the capacitor. This ensures that the core electrical performance of the capacitor, such as capacitance, loss tangent, and withstand voltage, remains undamaged after replacement.

[0022] The present invention will be further described below with reference to the embodiments.

[0023] Example 1: Combination Figure 2 and Figure 3 A slot 111 is provided on one side of the lower end of the plastic cover 11, and a block 121 is provided on one side of the lower end of the plastic cover 12. The corresponding arrangement of the slot 111 and the block 121 facilitates the plastic cover 12 and the plastic cover 11 to determine the sealing position and form a good protective effect.

[0024] The mica coating layer 13 is formed by spraying a fire-retardant coating made of mica powder and flame retardant. The mica coating layer 13 is bonded to the outer wall of the plastic cover 12 and the plastic shell 11 to form a flame-retardant layer.

[0025] Example 2: Combination Figure 4 and Figure 5 The capacitor assembly 3 includes a dielectric film 31 and an inner electrode metal foil 32 that are bonded together. The dielectric film 31 and the inner electrode metal foil 32 are stacked and wound from the inside out. The dielectric film 31 is an excellent insulator that can prevent direct current from passing through and avoid short circuits, while allowing AC signals to pass through under the action of an electric field, ensuring that the capacitor operates safely at the rated voltage. The inner electrode metal foil 32 is tightly bonded to the dielectric film 31 and is used for conduction. It has extremely low resistivity, which can reduce the loss when current passes through and improve high-frequency performance.

[0026] The capacitor assembly 3 also includes an outer electrode block 33 covering both sides of the inner electrode metal foil 32. The outer electrode block 33 gathers the internally dispersed inner electrodes and reliably connects them to the external pins 34. The outer electrode block 33 conducts all the inner electrodes at both ends through a vapor deposition process, forming two unified external conductive ends, corresponding to the positive and negative terminals of the capacitor. At the same time, it can reduce the corrosion of the capacitor assembly 3 by external moisture and impurities and improve the environmental stability of the capacitor.

[0027] External pins 34 are soldered on one side of the external electrode block 33. There are two sets of external pins 34. The two sets of external pins 34 are connected to the positive and negative terminals of the external circuit respectively to realize the input and output of current. They can also fix the capacitor on the PCB board or the equipment housing to prevent the capacitor from shifting or falling off due to vibration or impact.

[0028] External pin 34 is installed through the plastic cover 12. After the plastic cover 12 is inserted into the external pin 34, it is bonded to the plastic shell 11 by flame-retardant potting compound 2 to complete the encapsulation and fixation.

[0029] The dielectric film 31 and the inner electrode metal foil 32 are wound to form a flat cylindrical core. The cross-section of the flat cylindrical core is elliptical, which can reduce the overall PCB area occupied and improve the circuit integration. At the same time, for the same volume, the heat dissipation area of ​​the flat cylindrical core is larger than that of the cylindrical core, making the temperature distribution inside the capacitor more uniform.

[0030] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0031] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A flame-retardant protective film capacitor, comprising a flame-retardant shell (1), characterized in that: The flame-retardant outer shell (1) is filled with flame-retardant potting compound (2), and the flame-retardant potting compound (2) is filled with a capacitor assembly (3) for capacitor energy storage. The flame-retardant housing (1) includes a plastic sleeve (11) and a plastic cover (12) that are interlocked. The outer sides of the plastic sleeve (11) and the plastic cover (12) are provided with a mica coating layer (13). The flame-retardant potting compound (2) between the flame-retardant housing (1) and the capacitor assembly (3) is made of polyurethane.

2. The flame-retardant and protective film capacitor according to claim 1, characterized in that: The lower end of the plastic shell (11) is provided with a slot (111), and the lower end of the plastic cover (12) is provided with a protruding block (121).

3. The flame-retardant and protective film capacitor according to claim 1, characterized in that: The mica coating layer (13) is formed by spraying a fire-retardant coating made of mica powder and flame retardant.

4. A flame-retardant and protective film capacitor according to claim 1, characterized in that: The capacitor assembly (3) includes a dielectric film (31) and an inner electrode metal foil (32) that are bonded together, and the dielectric film (31) and the inner electrode metal foil (32) are stacked and wound from the inside out.

5. A flame-retardant and protective film capacitor according to claim 4, characterized in that: The capacitor assembly (3) also includes an outer electrode block (33) covering both sides of the inner electrode metal foil (32).

6. A flame-retardant and protective film capacitor according to claim 5, characterized in that: An external pin (34) is welded to one side of the external electrode block (33), and two sets of external pins (34) are provided.

7. A flame-retardant and protective film capacitor according to claim 6, characterized in that: The external pin (34) is disposed through the plastic cover (12).

8. A flame-retardant and protective film capacitor according to claim 4, characterized in that: The dielectric film (31) and the inner electrode metal foil (32) are wound to form a flat cylindrical core.

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