A low voltage capacitor overvoltage protection device chip and production method thereof

Abstract

The present invention discloses a low-voltage capacitor overvoltage protection device chip and a production method thereof, comprising a protection device body, an upper hollow plate is arranged on the top of the protection device body, a lower hollow plate is arranged on the bottom of the protection device body, the protection device body comprises an inner core plate, pins are welded on the outer walls of both sides of the inner core plate, a package body is arranged on the outside of the inner core plate, an upper mounting groove is arranged on the top outer wall of the package body, the upper hollow plate is located inside the upper mounting groove, an upper heat-conducting layer is arranged on the bottom outer wall of the upper hollow plate, and a uniformly distributed heat sink is formed integrally on the top outer wall of the upper hollow plate. The present invention arranges an upper hollow plate with a vacuum cavity on the protection device body, and injects pure water into the interior of the upper hollow plate, so that the protection device body can evaporate the pure water when working, and then the evaporated pure water is condensed and liquefied in the capillary layer at the top, so that the heat dissipation performance of the low-voltage capacitor overvoltage protection device chip is better when in use.

Description

Technical Field

[0001] The present invention relates to the technical field of overvoltage protection device chips, and in particular to a low-voltage capacitor overvoltage protection device chip and a production method thereof. Background Art

[0002] Low-voltage capacitors usually refer to power capacitors with rated voltages between 400V and 6kV. The function of low-voltage capacitors is to improve the power factor and thus reduce electricity costs, and to reduce the load on the equipment and increase its service life. In practical applications, low-voltage capacitors need to be protected by overvoltage protection chips, so that low-voltage capacitors are not easily damaged when subjected to high voltage.

[0003] Chinese patent number CN200910301945.6 discloses a low junction capacitance overvoltage protection thyristor device chip and its production method. The chip includes metal electrodes T1 and T2, N+ emitter region, N-type long base region, and P-type short base region. An outer groove is etched around the chip. An N-type ion implantation region is set up inside the chip. An N-type region buried layer is formed under the P-type short base region outside the etched groove. The production method is: after silicon wafer oxidation and before the P-type short base region diffusion step, three process steps are added, including double-sided photolithography of N-type ion implantation region, double-sided N-type ion implantation, N-type ion implantation oxidation and diffusion. After the P-type short base region is diffused, an N-type region buried layer is formed under the P-type short base region.

[0004] The overvoltage protection device chip used in low-voltage capacitors will generate heat during operation. If the heat is not dissipated in time, the overvoltage protection device chip will malfunction and thus fail to protect the low-voltage capacitor. Therefore, it is urgent to design a low-voltage capacitor overvoltage protection device chip and its production method to solve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a low voltage capacitor overvoltage protection device chip and a production method thereof to solve the above-mentioned deficiencies in the prior art.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A low-voltage capacitor overvoltage protection device chip comprises a protection device body, an upper hollow plate is arranged on the top of the protection device body, a lower hollow plate is arranged on the bottom of the protection device body, the protection device body comprises an inner core plate, pins are welded to the outer walls on both sides of the inner core plate, a package body is arranged on the outside of the inner core plate, an upper mounting groove is arranged on the top outer wall of the package body, the upper hollow plate is located inside the upper mounting groove, an upper heat conductive layer is arranged on the bottom outer wall of the upper hollow plate, a uniformly distributed heat dissipation plate is integrally formed on the top outer wall of the upper hollow plate, the interior of the upper hollow plate is vacuum, pure water is arranged on the interior of the upper hollow plate, a capillary layer is arranged on the inner wall of the upper hollow plate, the pin comprises a connecting plate, a supporting plate is integrally formed on the bottom of the connecting plate, a welding plate is integrally formed on the bottom outer wall of the supporting plate, and a silver-plated layer is arranged on the bottom outer wall of the welding plate.

[0008] Furthermore, a top outer wall of the welding plate is provided with a material injection hole, and a side outer wall of the welding plate is provided with a groove.

[0009] Furthermore, one inner wall of the groove is provided with concave holes which are centrally symmetrically distributed, and the inner wall of the concave holes is provided with textures.

[0010] Furthermore, an air inlet pipe is welded to an outer wall of one side of the lower hollow plate, and an air outlet pipe is welded to an outer wall of a side of the lower hollow plate away from the air inlet pipe.

[0011] Furthermore, a lower mounting groove is provided on the bottom outer wall of the packaging body, a convex shell is integrally formed on the top outer wall of the lower hollow plate, the convex shell is located inside the lower mounting groove, and an upper heat conducting layer is provided on the top of the convex shell.

[0012] Furthermore, the outer walls around the convex shell are integrally formed with convex edges, and the outer walls of the convex edges are provided with sealing grooves.

[0013] Furthermore, the upper hollow plate is made of copper, the lower hollow plate is made of aluminum alloy, and the upper heat-conducting layer and the lower heat-conducting layer are made of heat-conducting silicone.

[0014] A method for producing a low-voltage capacitor overvoltage protection device chip comprises the following steps:

[0015] Material selection steps: Select copper plates and aluminum alloy plates with uniform thickness;

[0016] Forming steps: evenly sprinkle sintering powder on the upper surface of the copper plate, then sinter the copper plate to form a capillary layer on the upper surface of the copper plate, and then cut, extrude and weld the copper plate and the aluminum alloy plate to form an upper hollow plate and a lower hollow plate respectively;

[0017] Liquid injection step: filter the water through a semi-permeable membrane to form pure water, and inject the pure water into the hollow plate;

[0018] Vacuuming step: extract the air inside the upper hollow plate and seal the vacuum port;

[0019] Assembly steps: stick the lower heat-conducting layer on the top of the lower hollow plate, stick the heat-conducting layer on the bottom of the upper hollow plate, and then fix the lower hollow plate to the inner core plate with pins through the lower heat-conducting layer;

[0020] Packaging step: put the inner core board and the upper hollow board into the mold, align their positions and then package them;

[0021] Furthermore, in the material selection step, the thickness of the copper plate and the aluminum alloy plate is 0.5mm-1mm, and in the packaging step, the distance between the upper hollow plate and the inner core plate is 3mm-6mm.

[0022] Furthermore, in the forming step, the sintering powder is made of any one of copper, nickel, aluminum and stainless steel, and the sintering time is 30 min-60 min.

[0023] In the above technical solution, the present invention provides a low-voltage capacitor overvoltage protection device chip and a production method thereof, which has the following beneficial effects:

[0024] (1) The present invention arranges an upper hollow plate with a vacuum cavity on the protection device body, and injects pure water into the interior of the upper hollow plate, so that the protection device body can evaporate the pure water when working, and then the evaporated pure water is condensed and liquefied in the capillary layer at the top, so that the heat dissipation performance of the low-voltage capacitor overvoltage protection device chip is better when in use.

[0025] (2) The present invention sets a lower hollow plate at the bottom of the protection device body, so that air can be passed into the lower hollow plate to remove the heat conducted to the lower hollow plate, thereby further improving the heat dissipation performance of the low-voltage capacitor overvoltage protection device chip when in use.

[0026] (3) The present invention provides grooves and concave holes on the welding plate of the pin, so that when welding the low-voltage capacitor overvoltage protection device chip to the circuit board, it is only necessary to drip solder into the injection hole, so that the solder can be automatically filled inside the grooves and concave holes, thereby preventing the phenomenon of excessive solder during welding and making the welding more firm.

[0027] (4) The present invention uses the convex edge and the sealing groove to achieve a better sealing effect between the packaging body and the lower hollow plate during packaging, thereby preventing the inner core plate from contacting the external air. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0029] Figure 1 The present invention provides an overall structural schematic diagram of a low-voltage capacitor overvoltage protection device chip and a production method thereof.

[0030] Figure 2 A schematic cross-sectional structure diagram of a low-voltage capacitor overvoltage protection device chip and a production method thereof according to an embodiment of the present invention.

[0031] Figure 3 A schematic diagram of the pin structure of a low-voltage capacitor overvoltage protection device chip and a production method thereof according to an embodiment of the present invention.

[0032] Figure 4 A schematic diagram of a groove structure provided for an embodiment of a low-voltage capacitor overvoltage protection device chip and a production method thereof according to the present invention.

[0033] Figure 5 This is a schematic diagram of the enlarged structure of point A provided in an embodiment of a low-voltage capacitor overvoltage protection device chip and a production method thereof of the present invention.

[0034] Figure 6 This is a schematic diagram of the enlarged structure at point B provided in an embodiment of a low-voltage capacitor overvoltage protection device chip and a production method thereof of the present invention.

[0035] Description of reference numerals:

[0036] 1 protective device body, 2 upper hollow plate, 3 lower hollow plate, 4 pins, 5 connecting plate, 6 supporting plate, 7 welding plate, 8 injection hole, 9 silver-plated layer, 10 groove, 11 concave hole, 12 upper mounting groove, 13 upper thermal conductive layer, 14 inner core plate, 15 lower mounting groove, 16 air inlet pipe, 17 air outlet pipe, 18 convex shell, 19 convex edge, 20 sealing groove, 21 texture, 22 package body, 23 capillary layer, 24 heat sink, 25 lower thermal conductive layer. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0038] like Figure 1-6As shown, a low-voltage capacitor overvoltage protection device chip and a production method thereof provided by an embodiment of the present invention include a protection device body 1, an upper hollow plate 2 is arranged on the top of the protection device body 1, a lower hollow plate 3 is arranged on the bottom of the protection device body 1, the protection device body 1 includes an inner core plate 14, pins 4 are welded on the outer walls of both sides of the inner core plate 14, a package body 22 is arranged on the outside of the inner core plate 14, an upper mounting groove 12 is arranged on the top outer wall of the package body 22, the upper hollow plate 2 is located inside the upper mounting groove 12, an upper heat conductive layer 13 is arranged on the bottom outer wall of the upper hollow plate 2, a uniformly distributed heat dissipation plate 24 is integrally formed on the top outer wall of the upper hollow plate 2, the interior of the upper hollow plate 2 is vacuum, pure water is arranged on the interior of the upper hollow plate 2, a capillary layer 23 is arranged on the inner wall of the upper hollow plate 2, the pin 4 includes a connecting plate 5, a support plate 6 is integrally formed on the bottom of the connecting plate 5, a welding plate 7 is integrally formed on the bottom outer wall of the support plate 6, and a silver-plated layer 9 is arranged on the bottom outer wall of the welding plate 7.

[0039] Specifically, in the present embodiment, a protection device body 1 is included, and the protection device body 1 is an overvoltage protection device chip used in a low-voltage capacitor in the prior art. An upper hollow plate 2 is arranged on the top of the protection device body 1, and the upper hollow plate 2 is hollow inside. A lower hollow plate 3 is arranged on the bottom of the protection device body 1. The lower hollow plate 3, the protection device body 1 includes an inner core plate 14, and the inner core plate 14 is a circuit inside the chip. Pins 4 are welded on the outer walls on both sides of the inner core plate 14. A package body 22 is arranged on the outside of the inner core plate 14, and the package body 22 protects the inner core plate 14. An upper mounting groove 12 is arranged on the top outer wall of the package body 22, and the upper hollow plate 2 is located inside the upper mounting groove 12. An upper heat-conducting layer 13 is arranged on the bottom outer wall of the upper hollow plate 2, and the upper heat-conducting layer 13 is utilized to prevent the heat of the protection device body 1 from working. The heat can be efficiently conducted to the upper hollow plate 2. The top outer wall of the upper hollow plate 2 is integrally formed with a uniformly distributed heat sink 24. The heat sink 24 has the effect of enhancing heat dissipation. The interior of the upper hollow plate 2 is a vacuum. Pure water is arranged inside the upper hollow plate 2. Pure water is easily evaporated when heated under a vacuum state. The inner wall of the upper hollow plate 2 is provided with a capillary layer 23. The capillary layer 23 acts as a circulation channel for the evaporation and liquefaction of pure water under a vacuum state. The pin 4 includes a connecting plate 5. The bottom of the connecting plate 5 is integrally formed with a support plate 6. The support plate 6 is used to ensure that the bottom of the protective device body 1 has sufficient air flow space after installation. The bottom outer wall of the support plate 6 is integrally formed with a welding plate 7. The bottom outer wall of the welding plate 7 is provided with a silver-plated layer 9. The silver-plated layer 9 is used to improve the conductivity of the pin welding point.

[0040] The present invention provides a low-voltage capacitor overvoltage protection device chip and a production method thereof. The present invention arranges an upper hollow plate 2 with a vacuum cavity on a protection device body 1, and injects pure water into the upper hollow plate 2, so that the protection device body 1 can evaporate the pure water when working, and then the evaporated pure water is condensed and liquefied in the capillary layer 23 at the top, so that the heat dissipation performance of the low-voltage capacitor overvoltage protection device chip is better when in use.

[0041] In another embodiment provided by the present invention, a filling hole 8 is provided on the top outer wall of the welding plate 7, a groove 10 is provided on one side outer wall of the welding plate 7, the filling hole 8 is cocentric with the groove 10, and a concave hole 11 is provided on one side inner wall of the groove 10 in a centrally symmetrical distribution, and a pattern 21 is provided on the inner wall of the concave hole 11. By providing the groove 10 and the concave hole 11 on the welding plate 7 of the pin 4, when welding the low-voltage capacitor overvoltage protection device chip to the circuit board, it is only necessary to drip solder into the filling hole 8, so that the solder can be automatically filled in the groove 10 and the concave hole 11, thereby preventing the phenomenon of excessive solder during welding and making the welding more firm.

[0042] In another embodiment provided by the present invention, an air inlet pipe 16 is welded to the outer wall of one side of the lower hollow plate 3, and an air outlet pipe 17 is welded to the outer wall of the side of the lower hollow plate 3 away from the air inlet pipe 16. Cooling air is introduced into the lower hollow plate 3 through the air inlet pipe 16. The air can take away the heat conducted to the lower hollow plate 3, thereby further improving the heat dissipation performance of the low-voltage capacitor overvoltage protection device chip during use. The upper hollow plate 2 is made of copper, the lower hollow plate 3 is made of aluminum alloy, and the upper heat-conducting layer 13 and the lower heat-conducting layer 24 are made of heat-conducting silicone.

[0043] In another embodiment provided by the present invention, a lower mounting groove 15 is provided on the bottom outer wall of the packaging body 22, and a convex shell 18 is integrally formed on the top outer wall of the lower hollow plate 3. The convex shell 18 is located inside the lower mounting groove 15, and an upper heat-conducting layer 13 is provided on the top of the convex shell 18. The upper heat-conducting layer 13 is utilized to efficiently conduct the heat of the protection device body 1 during operation to the lower hollow plate 3. A convex edge 19 is integrally formed on the outer walls surrounding the convex shell 18, and a sealing groove 20 is provided on the outer wall of the convex edge 19. The convex edge 19 and the sealing groove 20 can achieve a better sealing effect between the packaging body 22 and the lower hollow plate 3 during packaging, thereby preventing the inner core plate 14 from contacting the external air.

[0044] A method for producing a low-voltage capacitor overvoltage protection device chip comprises the following steps:

[0045] Material selection steps: Select copper plates and aluminum alloy plates with uniform thickness;

[0046] Forming step: evenly sprinkle sintering powder on the upper surface of the copper plate, then sinter the copper plate to form a capillary layer on the upper surface of the copper plate, and then cut, extrude and weld the copper plate and the aluminum alloy plate to form an upper hollow plate 2 and a lower hollow plate 3 respectively;

[0047] Liquid injection step: filter the water through a semi-permeable membrane to form pure water, and inject the pure water into the hollow plate;

[0048] Vacuuming step: extracting the air inside the upper hollow plate 2 and sealing the vacuum port;

[0049] Assembly steps: attach the lower heat-conducting layer 24 to the top of the lower hollow plate 3, attach the heat-conducting layer 13 to the bottom of the upper hollow plate 2, and then fix the lower hollow plate 3 to the inner core plate 14 with the pins 4 through the lower heat-conducting layer 24;

[0050] Packaging step: placing the inner core plate 14 and the upper hollow plate 2 into the mold, aligning them and then packaging them;

[0051] Furthermore, in the material selection step, the thickness of the copper plate and the aluminum alloy plate is 0.5 mm, and in the packaging step, the distance between the upper hollow plate 2 and the inner core plate 14 is 6 mm.

[0052] Furthermore, in the forming step, the sintering powder is made of any one of copper, nickel, aluminum and stainless steel, and the sintering time is 40 minutes.

[0053] Working principle: When in use, the protection device body 1 generates heat, the pure water inside the upper hollow plate 2 evaporates due to the heat, and then the evaporated pure water is condensed and liquefied in the capillary layer 23 at the top, thereby achieving efficient heat dissipation performance of the protection device body 1, and air is introduced into the lower hollow plate 3 through the air inlet pipe 16. The air introduced can take away the heat conducted to the lower hollow plate 3, thereby further improving the heat dissipation performance of the low-voltage capacitor overvoltage protection device chip when in use; when welding the low-voltage capacitor overvoltage protection device chip to the circuit board, it is only necessary to drip solder into the injection hole 8, so that the solder can be automatically filled in the groove 10 and the recessed hole 11, so that there will be no excessive solder during welding, and the welding will be more firm; through the convex edge 19 and the sealing groove 20, the sealing effect between the package body 22 and the lower hollow plate 3 is better during packaging, thereby preventing the inner core plate 14 from contacting the external air.

[0054] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A low voltage capacitor overvoltage protection device chip, characterized in that: The invention comprises a protection device body (1), wherein an upper hollow plate (2) is arranged on the top of the protection device body (1), and a lower hollow plate (3) is arranged on the bottom of the protection device body (1), wherein the protection device body (1) comprises an inner core plate (14), and pins (4) are welded to the outer walls on both sides of the inner core plate (14), and a packaging body (22) is arranged outside the inner core plate (14), and an upper mounting groove (12) is arranged on the top outer wall of the packaging body (22), and the upper hollow plate (2) is located inside the upper mounting groove (12), and an upper heat conducting layer (13) is arranged on the bottom outer wall of the upper hollow plate (2). ), the top outer wall of the upper hollow plate (2) is integrally formed with uniformly distributed heat dissipation plates (24), the interior of the upper hollow plate (2) is vacuum, the interior of the upper hollow plate (2) is provided with pure water, the inner wall of the upper hollow plate (2) is provided with a capillary layer (23), the pin (4) comprises a connecting plate (5), the bottom of the connecting plate (5) is integrally formed with a support plate (6), the bottom outer wall of the support plate (6) is integrally formed with a welding plate (7), and the bottom outer wall of the welding plate (7) is provided with a silver-plated layer (9); the top of the lower hollow plate (3) is affixed with a lower heat-conducting layer (25); The top outer wall of the welding plate (7) is provided with a material injection hole (8), and the bottom outer wall of the welding plate (7) is provided with a groove (10); One inner wall of the groove (10) is provided with concave holes (11) distributed symmetrically around the center, and the inner wall of the concave holes (11) is provided with patterns (21); An air inlet pipe (16) is welded to an outer wall of one side of the lower hollow plate (3), and an air outlet pipe (17) is welded to an outer wall of a side of the lower hollow plate (3) away from the air inlet pipe (16); The bottom outer wall of the packaging body (22) is provided with a lower mounting groove (15), the top outer wall of the lower hollow plate (3) is integrally formed with a convex shell (18), the convex shell (18) is located inside the lower mounting groove (15), and the top of the convex shell (18) is provided with an upper heat conducting layer (13); The convex shell (18) is integrally formed with a convex edge (19) on its four outer walls, and a sealing groove (20) is provided on the outer wall of the convex edge (19).

2. A low voltage capacitor overvoltage protection device chip according to claim 1, characterized in that: The upper hollow plate (2) is made of copper, the lower hollow plate (3) is made of aluminum alloy, and the upper heat-conducting layer (13) and the lower heat-conducting layer (25) are made of heat-conducting silicone.

3. A method for producing a low-voltage capacitor overvoltage protection device chip, comprising a low-voltage capacitor overvoltage protection device chip according to any one of claims 1 to 2, characterized in that: The following steps are involved: Material selection steps: Select copper plates and aluminum alloy plates with uniform thickness; Forming step: evenly sprinkle sintering powder on the upper surface of the copper plate, then sinter the copper plate to form a capillary layer on the upper surface of the copper plate, and then cut, extrude and weld the copper plate and the aluminum alloy plate to form an upper hollow plate (2) and a lower hollow plate (3) respectively; Liquid injection step: filter the water through a semi-permeable membrane to form pure water, and inject the pure water into the hollow plate; Vacuuming step: extracting the air inside the upper hollow plate (2) and sealing the vacuum port; Assembly steps: affixing a lower heat-conducting layer (25) to the top of the lower hollow plate (3), affixing a heat-conducting layer (13) to the bottom of the upper hollow plate (2), and then fixing the lower hollow plate (3) to the inner core plate (14) having the pins (4) via the lower heat-conducting layer (25); Packaging step: placing the inner core plate (14) and the upper hollow plate (2) into the mold, aligning them and then packaging them; 4. The method for producing a low voltage capacitor overvoltage protection device chip according to claim 3, characterized in that: In the material selection step, the thickness of the copper plate and the aluminum alloy plate is 0.5 mm to 1 mm, and in the packaging step, the distance between the upper hollow plate (2) and the inner core plate (14) is 3 mm to 6 mm.

5. The method for producing a low voltage capacitor overvoltage protection device chip according to claim 3, characterized in that: In the molding step, the sintering powder is made of any one of copper, nickel, aluminum and stainless steel, and the sintering time is 30 minutes to 60 minutes.

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