High-voltage pulse type high-precision wire-wound rod resistor

Abstract

The invention relates to the field of resistors, in particular to a high-voltage pulse type high-precision wire-wound rodlike resistor, the precision of the wire-wound rodlike resistor is + / -0.5%, the pulse withstand voltage is 6000V, the wire-wound rodlike resistor comprises a ceramic substrate, a cap, a metal lead and a resistance wire, the resistance wire adopts a 6J40 constantan wire rod, and the resistance wire is arranged on the ceramic substrate in a winding mode; the caps are 4J42 nickel-plated iron caps and are symmetrically arranged at the two ends of the ceramic substrate to form the resistor body, the leading-out end adopts a 4J43 lead, a 300 DEG C high-temperature-resistant paint layer is uniformly coated outside the resistor body, and the thickness of the 300 DEG C high-temperature-resistant paint layer is greater than or equal to 0.45 mm. The wire-wound rod-shaped resistor is mainly used for military high-voltage pulse electronic equipment and other pulse electronic circuits, has the characteristics of high precision, pulse resistance, high stability and the like, and can play roles in voltage division, current limiting, sampling and loading.

Description

Technical Field

[0001] The present invention relates to the field of resistors, and in particular to a high-voltage pulse type high-precision wire-wound rod-shaped resistor. Background Art

[0002] At present, the traditional wirewound resistors have an accuracy of ±5%, no pulse voltage requirements, and a stability level of ±2%. After 6000V pulse withstand voltage, the resistance value changes by ±1%, and after high temperature exposure and 2000 hours of aging, the resistance value changes by ±2%. The stability level of products used in defense and other military fields is relatively low. It can be seen that the existing wirewound resistors are difficult to take into account the high pulse and high precision stability under the impact of high-frequency pulse signals, and wirewound resistors will also have a relatively large risk of electrical performance changes when the operating environment requirements are relatively strict. Summary of the invention

[0003] To solve the above problems, the present invention provides a high-voltage pulse type high-precision wire-wound rod resistor, which can improve the accuracy of existing wire-wound resistor products to ±0.5%; the pulse withstand voltage is 6000V, which can provide a stable resistance value for electronic circuits under the impact of high-frequency pulse signals.

[0004] To achieve the above object, the technical solution adopted by the present invention is:

[0005] A high-voltage pulse type high-precision wire-wound rod resistor, the accuracy of which is ±0.5%, the pulse withstand voltage is 6000V, comprising a ceramic substrate, a cap, a metal lead and a resistance wire, the size of the ceramic substrate is 7mm×23mm, and the distance between the outer electrodes after the cap is pressed is 24mm; the resistance wire adopts 6J40 constantan wire and is arranged on the ceramic substrate in a winding manner; the cap adopts 4J42 nickel-plated iron cap, which is symmetrically arranged at both ends of the ceramic substrate to form a resistor body; the lead end adopts 4J43 lead; the resistor body is evenly coated with a layer of 300°C high-temperature resistant paint layer, the thickness of which is ≥0.45mm, to ensure that the product is not penetrated by the paint layer to meet the requirements.

[0006] Furthermore, the ceramic matrix adopts a high-aluminum ceramic matrix with an Al2O3 content of 95%, ensuring that the product has a certain heat dissipation capacity to meet various performance indicators of the product. The size of the ceramic matrix is ​​7mm×23mm.

[0007] Furthermore, the metal lead wire is made of 4J43 magnesium-plated wire and is connected to the outer side of the 4J42 nickel-plated iron cap.

[0008] Furthermore, the length and weight range of the resistance wire are designed according to the single pulse energy. Taking 10Ω as an example, the length of the resistance wire is 630.2mm-659.4mm, and the weight is 0.142-0.184g.

[0009] Furthermore, the number of turns of the resistance wire and the distance between the turns are determined according to the pulse limit voltage.

[0010] Furthermore, the 300°C high temperature resistant paint layer is

[0011] The wire-wound rod-shaped resistor of the present invention can be used for military high-voltage pulse electronic equipment and other pulse electronic circuits, and has the following beneficial effects:

[0012] 1) Use special 6J40 alloy wire, design the best number of winding coils and reasonable turn pitch to wind the product, and improve the product accuracy to ±0.5%; use high-aluminum porcelain matrix with good thermal conductivity and 95% AL2O3 content to ensure the product's heat dissipation capacity to meet the product's various electrical properties.

[0013] 2) The number of turns and the distance between turns are set according to the pulse limit voltage to ensure that the breakdown voltage is much greater than the 6KV pulse limit, the external electrodes will not break down, and the internal electrodes will not have the risk of creepage. According to the physical structure of the product and the withstand voltage of the paint layer, the relevant electrical stress aging and environmental stress aging are added in the process to improve the stability of the resistance value, and improve the reliability of the electrical performance of this product in the defense and other military fields.

[0014] 3) At present, there are no similar pulse-type precision wire-wound resistors with the same characteristics in China. Compared with the same type of products of Vishay, the international benchmark, domestic substitution can be achieved within a certain range, filling the gap in the field of domestic pulse-type precision wire-wound resistors. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0016] Figure 1 The present invention is a schematic structural diagram of a high-voltage pulse type high-precision wire-wound rod resistor according to an embodiment of the present invention.

[0017] In the figure: 1-ceramic substrate; 2-resistance wire; 3-cap; 4-coating paint layer; 5-metal lead. DETAILED DESCRIPTION

[0018] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements may be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0019] like Figure 1 As shown, a high-voltage pulse type high-precision wire-wound rod resistor of an embodiment of the present invention includes a ceramic substrate, a cap, a metal lead, a resistance wire and a coating paint layer. The ceramic substrate is a high-aluminum ceramic substrate with good thermal conductivity and an AL2O3 content of 95%, ensuring that the product has a certain heat dissipation capacity to meet various performance indicators of the product; the resistance wire is a 6J40 alloy wire with good consistency, small temperature coefficient and high melting point, which has a high melting point and can withstand large energy impact without flashing; the 6J40 alloy wire is arranged on the ceramic substrate in a winding manner, the length and weight range of the wire are designed according to the single pulse energy, the number of turns and the distance between turns are determined according to the pulse limit voltage, and the pulse characteristics are ensured; the cap is a nickel-plated iron cap with good stability and a relatively close expansion coefficient to the ceramic substrate, which is symmetrically arranged at both ends of the ceramic substrate to form a resistor body, the coating paint layer is evenly coated on the resistor body, and the metal lead is a 4J43 magnesium-plated wire with good thermal stability, which is connected to the outer side of the 4J42 nickel-plated iron cap.

[0020] Considering the physical structure of the product and the pressure resistance of the paint layer, the size of the ceramic substrate is selected to be 7mm×23mm. The distance between the outer electrodes after the cap is pressed is 24mm. The air breakdown voltage of 24mm is calculated. Through Paschen's law and table lookup, it is found that the breakdown voltage of 24mm exceeds 50KV, which is greater than the 6KV pulse limit, so there will be no breakdown between the outer electrodes. The distance between the inner electrodes is 17mm. Through calculation and table lookup, it is found that the breakdown voltage exceeds 50KV and is greater than the 6KV pulse limit, so there is no risk of creepage in the inner electrodes.

[0021] In order to increase the temperature impact of the resistor, the coating paint layer adopts a 300°C high temperature resistant paint layer. At the same time, relevant electrical stress aging and environmental stress aging are added in the process to improve the resistance stability, and defective products and pulse-resistant poor products are eliminated.

[0022] The design of the product of the present invention meets the special requirements of GJB2888-1997 and users. The pulse life test results are shown in the table below. The product identification meets the requirements of the detailed specification Q / RW20153-2018, and there are zero complaints about external quality.

[0023]

[0024] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art may make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A high-voltage pulse type high-precision wire-wound rod resistor, comprising a ceramic substrate, a cap, a metal lead and a resistance wire, characterized in that: The resistance wire is made of 6J40 alloy wire and is arranged on the ceramic substrate in a winding manner; the cap is made of nickel-plated iron cap, which is symmetrically arranged at both ends of the ceramic substrate to form a resistor body, and a 300°C high-temperature resistant paint layer is evenly coated on the outside of the resistor body.

2. A high-voltage pulse type high-precision wirewound rod resistor as claimed in claim 1, characterized in that: The ceramic matrix is ​​a high-aluminum ceramic matrix with an Al2O3 content of 95% and a size of 7mm×23mm.

3. A high-voltage pulse type high-precision wirewound rod resistor as claimed in claim 1, characterized in that: The metal lead wire is a 4J43 lead wire, which is connected to the outer side surface of a 4J42 nickel-plated iron cap.

4. A high-voltage pulse type high-precision wirewound rod resistor as claimed in claim 1, characterized in that: The thickness of the 300°C high temperature resistant paint layer is ≥0.45mm.

5. A high-voltage pulse type high-precision wirewound rod resistor as claimed in claim 1, characterized in that: The length and weight range of the resistance wire are designed according to the single pulse energy.

6. A high-voltage pulse type high-precision wirewound rod resistor as claimed in claim 1, characterized in that: According to the pulse limit voltage, the resistance wire is wound with 33 turns and a turn-to-turn distance of 0.34 mm, wherein the front angle is 60°, the front spacing is 0.8 mm, the rear angle is 45°, and the rear spacing is 0.8 mm.

7. A high-voltage pulse type high-precision wirewound rod resistor as claimed in claim 1, characterized in that: The precision of the wire-wound rod resistor is ±0.5%, and the pulse withstand voltage is 6000V (20us).

8. A high-voltage pulse type high-precision wirewound rod resistor as claimed in claim 1, characterized in that: The size of the ceramic substrate is 7mm×23mm, and the distance between the outer electrodes after capping is 24mm.

Images