An alloy current detection resistor with enhanced heat dissipation

Abstract

The present invention discloses an alloy current detection resistor with enhanced heat dissipation. Its basic principle is to increase the surface area of the resistor alloy part and the oxygen-free copper electrode part, so that the product has more surface area in contact with air, and forms convection and heat exchange with the surrounding ambient air to the greatest extent, thereby reducing the product temperature and improving the rated power and other performance of the product.

Description

Technical Field

[0001] The present invention relates to an alloy current detection resistor, and the specific specifications relate to products with alloys and electrodes of various chip and plug-in alloy resistors exposed to the air. Background Art

[0002] As Figure 1 shown, a commonly used alloy current detection resistor in the prior art includes an oxygen-free copper electrode 1 and a main resistor alloy 2 connected to both ends of the oxygen-free copper electrode 1. The alloy current detection resistor is in a sheet shape and formed into various shapes and sizes. The alloy current detection resistors commonly used in the prior art can also adopt other shapes not limited to Figure 1 the shape shown. In view of the current development of the new energy industry, the requirements for current detection resistors tend to be small volume and high power, and the power of the current detection resistor is mainly determined by the heat dissipation surface represented by the volume of the current detection resistor. It is usually very difficult to improve the heat dissipation capacity and thus increase the power of the current detection resistor without changing the volume.

[0003] Therefore, a new technical solution is needed to solve the above technical problems. Summary of the Invention

[0004] Aiming at the above problems, the purpose of the present invention is to provide an alloy current detection resistor that can reduce the product temperature and increase the product power.

[0005] To achieve the above target functions, the alloy current detection resistor of the present invention can adopt the following technical solutions:

[0006] An alloy current detection resistor with enhanced heat dissipation, including an oxygen-free copper electrode and a main resistor alloy connected to both ends of the oxygen-free copper electrode; characterized in that: grooves are formed on the upper surface of the oxygen-free copper electrode to increase the surface area of the oxygen-free copper electrode.

[0007] Further, the resistor alloy component is selected from at least one of manganin, copper manganese tin, nickel chromium aluminum silicon, copper manganese nickel or iron chromium alloy.

[0008] Further, the grooves include a plurality of grooves arranged in parallel on the upper surface of the oxygen-free copper electrode, and the cross-section of the grooves is an inverted isosceles triangle; the depth of the isosceles triangle groove is less than or equal to 1 / 3 of the thickness of the oxygen-free copper electrode, the length of the waist is greater than or equal to the length of the base, and the distance between the grooves and the groove edge is 0-1 mm.

[0009] Alternatively, the grooves include a plurality of grooves arranged in parallel on the upper surface of the oxygen-free copper electrode, the cross-section of the grooves is a rectangle, the depth of the rectangle is greater than or equal to the length of the base, the depth of the rectangle does not exceed 1 / 3 of the thickness of the oxygen-free copper electrode, the two side surfaces and the bottom surface of the rectangle are heat dissipation surfaces, and the distance between adjacent two grooves is not greater than the width of the grooves.

[0010] Alternatively, the groove includes several and is arranged in parallel on the upper surface of the oxygen-free copper electrode. The cross-section of the groove is a semi-circle, and the radius of the semi-circle is less than or equal to 1 / 3 of the thickness of the oxygen-free copper electrode. The semi-circular surface and the groove are heat dissipation surfaces; the margin interval between adjacent two grooves is not greater than 1 mm.

[0011] Furthermore, the current detection resistor is of the exposed type on the upper surface of the sheet electrode. When the current flows in through one oxygen-free copper electrode, flows through the resistance alloy, and flows out from the other oxygen-free copper electrode, the resistance alloy generates heat, and the heat is dissipated through the convection of the alloy and the air; the alloy reaches the oxygen-free copper electrode through conduction, and the electrode surface contacts the surrounding ambient air to reduce the product temperature and improve the power.

[0012] Furthermore, the oxygen-free copper electrode and the main body resistance alloy are welded into a whole by a welding process; the groove is formed by mechanical processing or chemical etching.

[0013] Beneficial effects: In the alloy current detection resistor provided by the present invention, by processing grooves on the oxygen-free copper electrode to increase the heat dissipation area, the product has more surfaces in contact with the air, enhancing heat dissipation. Thereby reducing the temperature of the product itself during operation, improving the power of the product, and enhancing the performance of the product.

[0014] The alloy current detection resistor with enhanced heat dissipation provided by the present invention can also adopt the following technical solutions:

[0015] An alloy current detection resistor with enhanced heat dissipation, comprising an oxygen-free copper electrode and a main body resistance alloy connected to both ends of the oxygen-free copper electrode; all surfaces of the current detection resistor are chemically etched to form pockmarks to increase the surface area.

[0016] Furthermore, the diameter of the pockmarks is between 0.2 - 1 mm, the height of the pockmarks is greater than or equal to the diameter of the pockmarks, but does not exceed 1 / 3 of the total thickness of the alloy current detection resistor; there is no interval between the bottoms of the pockmarks, and the utilization rate of the convex points per unit area is more than 78%.

[0017] Furthermore, six surfaces of the main body resistance alloy of the current detection resistor and six surfaces of the oxygen-free copper electrode are all or partially exposed. When the current flows in through one oxygen-free copper electrode, flows through the resistance alloy, and flows out from the other oxygen-free copper electrode, the resistance alloy generates heat, and the heat is dissipated through the convection of the alloy and the air; the alloy reaches the oxygen-free copper electrode through conduction, and the electrode surface contacts the surrounding ambient air, thereby reducing the product temperature and improving the power.

[0018] Beneficial effects: In the alloy current detection resistor provided by the present invention, all surfaces of the current detection resistor are chemically etched to form pockmarks to increase the heat dissipation area, so that the product has more surfaces in contact with the air, enhancing heat dissipation. Thereby reducing the temperature of the product itself during operation, improving the power of the product, and enhancing the performance of the product. Description of the Drawings

[0019] Figure 1 is a schematic diagram of an alloy current detection resistor in the prior art;

[0020] Figure 2 is a schematic diagram of the alloy current detection resistor of Embodiment 1 of the present invention;

[0021] Figure 3 is a schematic diagram of the alloy current detection resistor of Embodiment 2 of the present invention;

[0022] Figure 4 is a schematic diagram of the alloy current detection resistor of Embodiment 3 of the present invention;

[0023] Figure 5 is a schematic diagram of the alloy current detection resistor of Embodiment 4 of the present invention. Detailed implementation manners

[0024] The following makes a detailed description of the embodiments of the present invention:

[0025] The following describes the present invention in detail with reference to the drawings and embodiments.

[0026] Embodiment 1

[0027] Please refer to Figure 2 As shown, an enhanced heat dissipation alloy current detection resistor provided in this embodiment includes an oxygen-free copper electrode 1-1 and a main resistance alloy 1-2 welded to both ends of the oxygen-free copper electrode 1-1. Both ends of the resistance alloy are welded with oxygen-free copper as electrodes by electron beam, laser, etc. To prevent high-temperature oxidation, the welding is carried out in a vacuum state, and the vacuum degree of the welding chamber is lower than 5*10 - 3 Pa. When the strip thickness is less than 1 mm, the beam current is selected between 20 - 75 mA; when the strip thickness is more than 1 mm, the beam current is selected between 40 - 100 mA; combined with the tape running speed to achieve the best welding effect.

[0028] Welding speed: when the material thickness is more than 0.1 mm, the feeding speed is 1500 - 2000 mm / min; when the material thickness is more than 0.3 mm, the feeding speed is 1000 - 1500 mm / min; when the material thickness is more than 1 mm, the feeding speed is 800 - 1500 mm / min; when the material thickness is more than 2 mm, the feeding speed is 800 - 1000 mm / min; when the material thickness is more than 0.1 mm, the feeding speed is 500 - 1000 mm / min.

[0029] Cooperation scheme of the resistance alloy and oxygen-free copper: the thickness of the resistance alloy is equal to the thickness of the oxygen-free copper; the thickness of the resistance alloy is less than the thickness of the oxygen-free copper; the thickness of the resistance alloy is greater than the thickness of the oxygen-free copper;

[0030] Welding surface: single-sided welding, double-sided welding.

[0031] Grooves 1-3 are formed on the upper surfaces of the oxygen-free copper electrodes 1-1 at both ends to increase the surface area of the oxygen-free copper electrodes. The cross-section of the groove 1-3 is an inverted isosceles triangle. The specific processing method is to process the material into an inverted triangular groove 1-3 by mechanical processing or die forming before the product is formed; or to form it into an inverted triangular groove in one step with a die during the product forming process. The two waists on both sides of the isosceles triangular groove are heat dissipation surfaces. When the thickness of the oxygen-free copper electrode is greater than or equal to 0.3 mm, the maximum groove depth of the groove is 0.1 mm; when the thickness of the oxygen-free copper electrode is greater than or equal to 1 mm, the maximum groove depth of the groove is 0.3 mm; when the thickness of the oxygen-free copper electrode is greater than or equal to 2 mm, the maximum groove depth of the groove is 0.6 mm; when the thickness of the oxygen-free copper electrode is greater than or equal to 3 mm, the maximum groove depth of the groove is 1 mm.

[0032] According to the groove depth of 0.1 mm, the triangular opening size is 0.08 - 0.1 mm, and the heat dissipation area increases by 1.73 - 2.29 times; according to the groove depth of 0.3 mm, the triangular opening size is 0.2 - 0.3 mm, and the heat dissipation area increases by 1.7 - 1.8 times; according to the groove depth of 0.6 mm, the triangular opening size is 0.3 - 0.6 mm, and the heat dissipation area increases by 1.73 - 3.87 times; according to the groove depth of 1 mm, the triangular opening size is 0.5 - 1 mm, and the heat dissipation area increases by 1.73 - 1.93 times. The distance between the grooves and the groove edge is 0 - 1 mm.

[0033] When current flows through one end electrode, through the resistance alloy body, and then flows out from the other end electrode, a temperature higher than the ambient temperature is generated when the current flows through the resistance alloy body. Heat exchange is formed with the air through the increased surface area of the rectangular groove to achieve the effect of cooling.

[0034] Embodiment 2

[0035] Combined with Figure 3 As shown, an alloy current detection resistor for enhancing heat dissipation provided in this embodiment is substantially the same in structure as that in Embodiment 1, and also includes oxygen-free copper electrodes 2-1 and a main body resistance alloy 2-2 welded at both ends. The difference is that the cross-section of the groove 2-3 on the upper surface of the oxygen-free copper electrode 2-1 is rectangular. The two side surfaces and the bottom surface of the rectangle are heat dissipation surfaces, and the groove depth of the groove 2-3 is less than or equal to 1 / 3 of the thickness of the oxygen-free copper electrode. The best ratio of the depth-width ratio of the groove is 1 - 1.5, and the heat dissipation area increases by 3 - 4 times. The distance between the grooves shall not be greater than the width of the groove.

[0036] Embodiment 3

[0037] Combined with Figure 4As shown in the figure, an alloy current detection resistor with enhanced heat dissipation provided in this embodiment has a structure substantially the same as that of the first embodiment, and also includes an oxygen-free copper electrode 3-1 and a main resistance alloy 3-2 welded to both ends. The difference is that the cross-section of the groove 3-3 on the upper surface of the oxygen-free copper electrode 3-1 is semi-circular. Stripes are distributed on the semi-circular surface, which are respectively located on the upper surfaces of the oxygen-free copper electrodes at both ends. The semi-circular surface groove is the heat dissipation surface. The semi-circular surface is 3.14 times the diameter, the groove depth is 0.1 - 0.5 mm, and the heat dissipation area increases by more than 3.5 times. The distance between the grooves and the groove edge is 0 - 1 mm.

[0038] Embodiment Four

[0039] Combined with Figure 5 As shown in the figure, this embodiment discloses an alloy current detection resistor with enhanced heat dissipation, including an oxygen-free copper electrode 4-1 and a main resistance alloy 4-2 connected to both ends of the oxygen-free copper electrode 4-1. The six surfaces of the main resistance alloy 4-2 and the oxygen-free copper electrode 4-1 are micro-etched to form pockmarks on the product surface, increasing the surface area. The working temperature of the product is reduced and the power of the product is increased.

[0040] For the processing of the pockmarks, an exposure and development process is adopted. A photosensitive film is attached to the surface of the alloy resistor; the parts to be removed are exposed through exposure and development, where the exposure light source is parallel yellow light, the exposure time is 2 - 5 s, the temperature of the developer is 35 - 55 °C, and the development time is 5 - 15 min; the exposed metal is removed by the etching solution, where the temperature of the etching solution is 40 - 70 °C and the etching time is 2 - 15 min.

[0041] The etched pattern is a frustum of a cone or a trapezoid. According to the material thickness, when the material thickness is greater than or equal to 0.3 mm, the maximum groove depth is 0.1 mm; when the material thickness is greater than or equal to 1 mm, the groove depth is 0.3 mm; when the material thickness is greater than or equal to 2 mm, the maximum groove depth is 0.6 mm; when the material thickness is greater than or equal to 3 mm, the maximum groove depth is 1 mm. The ratio of the groove depth to the bottom diameter of the frustum of a cone and the diagonal of the bottom surface of the trapezoid is more than 1 time, and the most preferred is 1 - 1.5 times, and the heat dissipation area increases by 6.51 - 10.21 times.

[0042] The current flows in through one oxygen-free copper electrode, flows through the resistance alloy, and flows out from the other oxygen-free copper electrode. The resistance alloy generates heat, and the heat is dissipated through the convection of the alloy and the air; the alloy reaches the oxygen-free copper electrode through conduction, and the surface of the electrode contacts the surrounding ambient air, thereby reducing the product temperature and increasing the power.

[0043] The technical means disclosed in the solutions of the present invention are not limited to the technical means disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. An alloy current detection resistor for enhancing heat dissipation, comprising a main body resistance alloy and oxygen-free copper electrodes connected to both ends of the main body resistance alloy; characterized in that: All surfaces of the current detection resistor are chemically etched to form pockmarks to increase the surface area; all or part of the outer surfaces of the main body resistance alloy and the oxygen-free copper electrodes of the current detection resistor are exposed. When current flows in through one oxygen-free copper electrode, passes through the resistance alloy, and flows out from the other oxygen-free copper electrode, the electrode surface is in contact with the surrounding ambient air.

2. The alloy current detection resistor according to claim 1, wherein: The diameter of the pockmarks is between 0.2 and 1 mm, the height of the pockmarks is greater than or equal to the diameter of the pockmarks, but does not exceed 1 / 3 of the total thickness of the alloy current detection resistor; there is no gap between the bottoms of the pockmarks, and the utilization rate of the convex points per unit area is more than 78%.

Images