A grounding resistor for electric locomotive body grounding system

Abstract

A grounding resistor for an electric locomotive body grounding system, the grounding resistor is arranged between the grounding carbon brush of the electric locomotive body grounding system and the body; the grounding resistor comprises a resistor body, a terminal and a box; the terminal is two terminals respectively connected to the two ends of the resistor body, one of the two terminals is connected to the body, and the other is connected to the grounding carbon brush, and the body current is suppressed by the grounding resistor; the resistor body of the grounding resistor is a tubular grounding resistor body, and the two ends of the resistor body with a hollow annular columnar structure are connected by an annular terminal matching the shape of the resistor body with a hollow annular columnar structure, forming an input and output connection of the resistor body with a hollow annular columnar structure. The present invention greatly reduces the weight of the entire grounding resistor by hollowing out the resistor body, and effectively realizes the lightweight of the grounding resistor; it has the characteristics of simple structure, light weight, and easy replacement, and is suitable for popularization and application.

Description

Technical Field

[0001] The present invention relates to a component device of an electric locomotive grounding system, and in particular to a grounding resistor used in an electric locomotive body grounding system; the grounding resistor used in an electric locomotive body grounding system can effectively reduce the weight of the body grounding system and realize lightweight body components; and belongs to the technical field of electric locomotive manufacturing. Background Art

[0002] In order to ensure the personal safety of on-board personnel and the electrical safety of on-board equipment, electric locomotives need to discharge current during the process of bow-net offline, excessive phase internal overvoltage and external overvoltage such as lightning strike, and this current discharge is completed through the locomotive grounding system; the locomotive grounding system mainly consists of two parts, namely the body grounding and the on-board electrical equipment grounding. Among them, the grounding of on-board electrical equipment focuses on the grounding method of the high-voltage cable shielding layer, and the grounding method of the locomotive grounding system varies greatly for different models.

[0003] The locomotive grounding system must be suitable for the locomotive. An inappropriate locomotive grounding system is not only prone to uneven current distribution, but also voltage differences at different grounding points, forming local circulation. Part of the current may leak into certain parts of the locomotive, causing electrical corrosion to the parts and affecting the normal operation of the parts. In addition, an inappropriate locomotive grounding system may also cause the body contact voltage to rise, which not only seriously threatens the personal safety of the personnel in the car, but also counterattacks the on-board equipment (especially the equipment installed between the bogie and the car body, causing damage to it; it may even cause circuit insulation breakdown and burning of electronic components in the control and communication systems, posing a huge threat to the normal operation of the EMU. In particular, the body grounding of the EMUs and urban and subway rail vehicles that are now being widely promoted, these car bodies all use pot alloy car bodies. Since the resistance of the pot alloy car body is less than that of the rail, the traction return current forms a loop through the car body bogie-car body-adjacent car body-adjacent car body bogie. This loop makes the EMU car body current larger, affecting the service life of the car body grounding device and the bogie bearing.

[0004] In order to eliminate this effect, a resistive vehicle body grounding method is now proposed. The so-called resistive vehicle body grounding is to connect a grounding resistor between the working ground and the protective grounding to suppress the vehicle body current; the main circuit of this resistive vehicle body grounding method is directly grounded through a grounding carbon brush, and an isolation resistor is added between the vehicle body and the grounding carbon brush, that is, the vehicle body is grounded through an isolation resistor. Normally, the sliding electrical contact resistance between the grounding carbon brush and the axle is in the order of milliohms, so the traction current mainly enters the ground through the grounding carbon brush, and the component entering the vehicle body through the isolation resistor is relatively small, avoiding the body circulation; in addition, due to the addition of the body grounding resistor, the impedance of the body circuit increases, effectively suppressing the induced current generated by the traction current in the body circuit. However, the defect of this resistive vehicle body grounding method is that when a lightning trip or overvoltage shock occurs, the arrester or grounding switch is closed, and the transient impact current will be loaded on the grounding resistor, causing the vehicle body voltage to rise instantly. Since the vehicle body is the common reference ground for weak current signals, the counter-attack caused by the impact voltage may damage the weak current equipment such as vehicle control and communication. At the same time, when the arrester is turned on, the grounding resistor is in parallel with the transformer of the main circuit, and the high-voltage lightning wave will still be loaded on both ends of the vehicle transformer, and will be coupled to the secondary side through the transformer, which is easy to cause damage to the rectifier. In addition, in the current lightweight design of the vehicle body, this resistive vehicle body grounding method needs to be connected to a grounding resistor, and the current grounding resistors are all made of a resistor body structure of a spiral resistor bar. The resistor body of this spiral resistor bar structure not only greatly increases the weight of the entire grounding resistor, affecting the lightweight transformation of the vehicle body, but also easily generates inductance, causing the resistor body to heat up, causing the grounding resistor to burn out; therefore, it is necessary to study and improve this.

[0005] Through patent search, no relevant patent technology literature has been found. The closest one is a paper. The relevant literatures are as follows:

[0006] 1. Patent number CN201822007062.1, the utility model patent named "A locomotive grounding resistor", discloses a locomotive grounding resistor, including a shell, a spiral resistor bar, an insulating middle support member and an insulating end support member, the end support members have two groups respectively fixed to the shell, the two ends of the spiral resistor bar are respectively fixed to the two groups of end support members, a gap is left between the middle part of the spiral resistor bar and the shell, the middle support member presses against the middle part of the spiral resistor bar, thereby separating the middle part of the spiral resistor bar from the shell; an elastic member is provided between the middle support member and the shell, so that the middle support member elastically presses against the shell in a direction perpendicular to the spiral direction of the spiral resistor bar.

[0007] 2. The invention patent with the patent number CN201510431603.1 and the name of it is "A method for controlling the grounding resistance of a rail vehicle and its grounding plate". This patent discloses a method for controlling the grounding resistance of a rail vehicle, including the following steps: 1) Dividing the grounding resistance into three sub-resistors connected in series; 2) Allocating the resistance range of each sub-resistor; 3) Controlling each sub-resistor separately so as to control its resistance value within the corresponding resistance range. First, the grounding resistance is divided into three sub-resistors, and then the resistance range of each sub-resistor is allocated, and then the sub-resistors are controlled separately according to each resistance range, so as to control each sub-resistor within its own resistance range, thereby achieving controllable vehicle body grounding, improving grounding reliability, and thus improving driving stability and safety.

[0008] 3. The patent number is CN201420050674.8, and the utility model patent named "Ring-shaped terminal type thick-film non-inductive high-voltage voltage-dividing resistor" discloses a ring-shaped terminal type thick-film non-inductive high-voltage voltage-dividing resistor. The resistor includes an alumina ceramic rod and two nickel-plated copper caps. The two nickel-plated copper caps are correspondingly installed on the two ends of the alumina ceramic rod. Electrodes and a resistor slurry layer are sintered on the surface of the alumina ceramic rod, and the two ends of the resistor slurry layer are respectively connected to the electrodes. After the alumina ceramic rod is sintered with the electrode and the resistor slurry layer, a resistor body is formed, and the surface of the resistor body is coated with insulating paint; a ring-shaped terminal is fixedly connected to the electrode.

[0009] Through the analysis of the above patent documents, we found that the only utility model patent that truly involves the grounding resistor in the locomotive grounding system is the patent number CN201822007062.1, named "A locomotive grounding resistor"; the structure disclosed in this patent is indeed the grounding resistor used in current electric locomotives, especially EMUs, but the structure disclosed in this patent is still only a grounding resistor structure using a spiral resistor strip, so the problems mentioned above still exist, and it is still necessary to conduct further research on this. Summary of the invention

[0010] The purpose of the present invention is to address the shortcomings of the existing electric locomotive body grounding system and propose a new grounding resistor for body grounding of the electric locomotive body grounding system. The grounding resistor for body grounding of the electric locomotive body grounding system can effectively further reduce the overall weight of the body grounding resistor while maintaining the effectiveness of the grounding resistor, thereby improving the lightweight level of the body grounding system.

[0011] In order to achieve this object, the present invention provides a grounding resistor for an electric locomotive body grounding system, wherein the grounding resistor is arranged between a grounding carbon brush of the electric locomotive body grounding system and the body; the grounding resistor comprises a resistor body, a wiring terminal and a box body; the wiring terminals are two terminals respectively connected to the two ends of the resistor body, one of the two wiring terminals is connected to the body, and the other is connected to the grounding carbon brush, so that the body current is suppressed by the grounding resistor; the resistor body of the grounding resistor is a tubular grounding resistor body, and the two ends of the resistor body with a hollow ring column structure are connected by ring wiring terminals matching the shape of the resistor body with a hollow ring column structure, so as to form an input and output connection of the resistor body with a hollow ring column structure.

[0012] Furthermore, the tubular grounding resistor is a resistor having a hollow annular columnar structure with a metal tube as the base, formed by compounding a layer of resistor material on the base of the tubular metal cylinder.

[0013] Furthermore, the metal cylinder is a stainless steel tube, and the resistor body with a hollow ring-shaped columnar structure is compounded on the substrate of the stainless steel tube; an insulating layer is first compounded on the outer surface of the stainless steel tube, and then a resistor layer is compounded on the insulating layer to form a resistor body with a hollow ring-shaped columnar structure with the stainless steel tube as the substrate.

[0014] Furthermore, the metal cylinder is an aluminum alloy or copper alloy cylinder, and a resistor layer is compounded on the base of the aluminum alloy or copper alloy cylinder to form a resistor body with a hollow annular columnar structure with the aluminum alloy or copper alloy cylinder as the base.

[0015] Furthermore, the metal cylinder is a single tube, a double tube, or multiple tubes; the shape of the tube includes a circle, an ellipse, or a polygon.

[0016] Furthermore, the metal cylinders are two parallel bodies, and the ends of the two metal cylinders are connected by welding through metal brackets made of the same material as the cylinders to form a whole, and then the metal brackets are fixed to the box body in an insulating manner.

[0017] Furthermore, the resistor body of the hollow ring column structure is installed in the box through secondary insulation, and the input and output are connected to the vehicle body through the grounding carbon brush of the vehicle body grounding system using a double insulation wiring method.

[0018] The grounding resistor for the electric locomotive body grounding system as claimed in claim 3 or 4 is characterized in that: a protective layer is also compounded on the resistance layer; the protective layer is a protective film with heat dissipation performance.

[0019] Furthermore, the protective layer is a protective layer formed by a composite of insulating and heat-conducting materials; including thermally conductive silicone grease, thermally conductive silica gel, or nano-composite organic silicon material.

[0020] Furthermore, a metal braided ribbon is provided between the ring-shaped terminal and the resistor body with a hollow ring-column structure to ensure that the ring-shaped terminal and the resistor body with a hollow ring-column structure are tightly combined together. The metal braided ribbon ensures that the ring-shaped terminal and the resistor body with a hollow ring-column structure can fit tightly together in the entire ring shape.

[0021] Furthermore, the metal woven wire mesh is a silver-plated metal woven wire mesh, and silver is plated on the surface of the metal woven wire mesh.

[0022] Furthermore, the thickness of the resistor layer of the resistor of the hollow ring columnar structure is determined by calculation according to the needs of the grounding resistance, ensuring that the total resistance value of the metal matrix cylindrical resistor is the resistance value of the original spiral resistor.

[0023] The advantages of the present invention are:

[0024] The present invention adopts a cylindrical resistor to replace the original spiral resistor, which can significantly reduce the weight of the resistor under the same resistance value and eliminate the inductance of the spiral resistor. It has the following advantages:

[0025] 1. Using a hollow ring-shaped resistor to replace the original spiral resistor can greatly reduce the weight of the resistor, which is beneficial to the lightweight of the entire vehicle grounding system;

[0026] 2. The hollow ring-shaped resistor body adopts a thin-walled stainless steel cylinder, which can further reduce the weight of the cylindrical resistor body, thereby further reducing the weight of the entire grounding resistor;

[0027] 3. A resistor is compounded on a hollow ring-shaped stainless steel cylinder, and the resistor is connected to the grounding carbon brush of the vehicle grounding system and the vehicle body through the hollow ring-shaped resistor, which can effectively expand the surface area of ​​the resistor and improve the efficiency of the resistor;

[0028] 4. The hollow ring-shaped resistor is wired in the form of a ring-shaped terminal, and a silver-plated metal braided belt is arranged under the ring-shaped terminal to ensure the overall effect of the hollow ring-shaped resistor and avoid the phenomenon of local short circuit;

[0029] 5. The hollow ring-shaped resistors are supported by stainless steel brackets and connected by laser welding of connecting plates, which has the characteristics of good welding effect and beautiful appearance;

[0030] 6. The hollow ring-shaped resistor is installed on the grounding resistor box through secondary insulation, which has the characteristics of reliable insulation and strong anti-interference ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is the principle diagram of locomotive grounding resistance;

[0032] Figure 2 is a three-dimensional structural diagram of an embodiment;

[0033] Figure 3 It is a three-dimensional schematic diagram of a hollow ring-shaped resistor in a box according to an embodiment of the present invention;

[0034] Figure 4 It is a schematic cross-sectional structure diagram of a hollow ring-shaped resistor according to an embodiment of the present invention;

[0035] Figure 5 It is a schematic diagram of the connection between the integral ring-shaped terminal and the tubular grounding resistor according to an embodiment of the present invention;

[0036] Figure 6 This is the exploded structure diagram of the tubular grounding resistor body with the entire metal cylinder as the base. DETAILED DESCRIPTION

[0037] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. Embodiment 1

[0038] As attached Figure 1 and 2 As shown, a grounding resistor for an electric locomotive body grounding system, the grounding resistor 1 is arranged between a grounding carbon brush 2 and a body 3 of the electric locomotive body grounding system; the grounding resistor 1 comprises a resistor body 4, a wiring terminal 5 and a box body 6; the wiring terminal 5 is two terminals connected to the two ends of the resistor body 4 respectively, one of the two wiring terminals 5 is connected to the body 3, and the other is connected to the grounding carbon brush 2, and the body current is suppressed by the grounding resistor 1; the resistor body 4 of the grounding resistor is a tubular grounding resistor body.

[0039] The use of this tubular grounding resistor as the grounding resistor in the vehicle body grounding system is to reduce the weight of the resistor by hollowing the resistor. Through research, it is found that under the same surface load, the use of a tubular grounding resistor can not only greatly reduce the weight of the resistor, but also has better resistance effect and smaller volume than a solid resistor spirally coiled into a spiral tubular resistor; therefore, the use of a tubular grounding resistor can completely replace the existing spiral resistor, thereby effectively reducing the weight of the resistor. While reducing weight, the use of an integral tubular grounding resistor can also effectively eliminate the problem of strong inductance caused by the original spiral tube-shaped resistor, and effectively reduce the self-heating of the grounding resistor; research has found that the original spiral tube-shaped resistor was used to ensure sufficient total resistance value. The use of a spiral tube can greatly shorten the length of the resistor, but this increases the resistor's own inductance, and in order to ensure the resistance effect, it must be ensured that there is a certain gap between the spiral tube-shaped resistor coils, which will increase the length of the spiral tube-shaped resistor; the use of a tubular grounding resistor not only eliminates the gap between the spirals, which can effectively shorten the length of the resistor, but also eliminates the resistance cross-section loss caused by the round rod shape of the spiral tube-shaped resistor due to the use of a round rod for winding.

[0040] However, if the tubular grounding resistor is directly installed in the vehicle body grounding system, the tubular grounding resistor must have good strength and rigidity, otherwise the resistor will break under the vibration environment of the locomotive body. Simply improving the strength of the resistor requires adding enough metal elements to increase the rigidity of the tubular grounding resistor when making the tubular grounding resistor, which will affect the resistance performance of the resistor. Therefore, the present invention adopts a composite structure, attaching the tubular grounding resistor 7 to a metal cylinder 8 with sufficient strength, so that the main consideration of the tubular grounding resistor 7 is how to improve the resistance performance; after repeated research, it is finally found that stainless steel is the most suitable supporting matrix for the tubular grounding resistor 7, because stainless steel has good corrosion resistance, which can effectively prevent the tubular grounding resistor from peeling off on the matrix. If other metal materials (such as ordinary high-quality carbon steel) are used, the tubular grounding resistor 5 will peel off from the matrix wall after a period of use, thereby affecting the performance of the resistor; of course, other materials such as copper alloy tubes or aluminum alloy tubes can also be used as the matrix to obtain good results.

[0041] In order to provide reliable support for the tubular grounding resistor 5, the tubular grounding resistor 7 is composited on the hollow stainless steel metal cylinder 8, and the thin-walled hollow stainless steel metal cylinder 8 is used as the attachment substrate of the tubular grounding resistor. This can further reduce the weight of the entire grounding resistor, which is beneficial to the lightweight of the grounding resistor; the wall thickness of the stainless steel metal cylinder 8 can be selected to be 2-5 mm.

[0042] The tubular grounding resistor can be one, two, or more, depending on the surface load of the vehicle body on the grounding resistor and the spatial position of the grounding resistor box on the vehicle body. This embodiment uses two (such as the attached Figure 3 As shown); when more than two tubular grounding resistors 7 are used, each tubular grounding resistor 7 is connected in series and parallel; the hollow stainless steel cylinders 8 attached to the two or more tubular grounding resistors 7 are connected together by laser welding through a connecting bracket 9, so that the entire tubular grounding resistor 7 forms a whole; and the connecting bracket 9 is fixed to the bottom plate 10 of the box 6 of the grounding device in an insulating manner through an insulator 11.

[0043] The present invention proposes that the tubular grounding resistor 7 is attached to the hollow stainless steel cylinder 8 by compounding a layer of resistor material on the stainless steel cylinder 8 substrate to form a tubular grounding resistor 7 with the hollow stainless steel cylinder 8 as the substrate. Figure 4 As shown; however, the tubular grounding resistor and the stainless steel cylinder are insulated and isolated from each other, and an insulating layer 13 is provided between the tubular grounding resistor and the stainless steel cylinder to prevent the current on the tubular grounding resistor 7 from leaking to the stainless steel cylinder 8; and the stainless steel cylinder 8 is fixed to the box 6 of the grounding device in an insulating manner through a connecting bracket 9, and the connecting bracket 9 and the box 6 of the grounding device are also insulated and fixedly connected to form a secondary insulation structure.

[0044] Since the grounding resistance environment under the vehicle body is very bad, in order to effectively protect the tubular grounding resistor 7, a protective film 14 is compounded on the outer surface of the tubular grounding resistor 7. This protective film 14 needs to have good heat dissipation and protection performance. After research, thermal conductive silicone grease, thermal conductive silica gel, or nano-composite organic silicon material is most suitable. The thickness of the resistor layer of the tubular grounding resistor is determined by calculation according to the needs of the grounding resistance; the overall resistance value of the tubular grounding resistor with the metal cylinder as the base is preferably the same as the resistance value of the original spiral resistor.

[0045] As attached Figure 5As shown, the connection between the tubular grounding resistor 7 and the vehicle body and the grounding brush in the vehicle body grounding system is that connecting wires 15 are led out from both ends of the tubular grounding resistor, one end is connected to the vehicle body, and the other end is connected to the grounding brush; for the connection method of the tubular grounding resistor 7, if a single-point wiring method is adopted like the original spiral resistor, it is easy for the current to take the shortest route, resulting in the phenomenon that the current of the tubular grounding resistor is too concentrated; therefore, when an annular tubular resistor is adopted, how to ensure that the entire resistor can play an effective role becomes a key point; in order to ensure the overall effect of the tubular grounding resistor, the present invention proposes to connect the two ends of the resistor by means of an integral annular terminal, and a metal conductive pad 16 is provided under the annular terminal to ensure that the annular terminal 17 is in overall contact with the tubular grounding resistor 7, so as to ensure that the resistance values ​​at both ends of the entire annular surface of the annular tubular grounding resistor 7 are of equal potential; thereby, the grounding effect of the grounding resistor can be ensured, and the phenomenon of short circuit due to inconsistent local resistance values ​​can be avoided. And in order to prevent the formation of eddy currents in the tubular resistor 7, the tubular grounding resistor 7 is manufactured in an open manner, leaving a gap between the entire annular cylinder, the width of the gap is 5-10mm, the gap is filled with an insulating layer material, and both sides of the gap are kept insulated.

[0046] The metal conductive pad 16 is connected to the two ends of the resistor body by the wiring method of an integral ring terminal, and one or more layers of silver-plated metal braided tape are firstly wound around the two ends of the tubular grounding resistor body 7 with a metal cylinder as the base; the silver-plated metal braided tape is stacked into a long strip with the same width as the ring terminal 17, and then wound around the two ends of the tubular grounding resistor body with a metal cylinder as the base to form the metal conductive pad 16, and is clamped by the joint bolts of the ring terminal 17, so that the silver-plated metal wire mesh and the resistor body of the tubular grounding resistor body with the metal cylinder as the base are closely attached together, forming a ring terminal The circumference of the tubular grounding resistor is fully contacted, so that the overall overcurrent path of the tubular grounding resistor body can be ensured to be basically consistent, as shown in the attached Figure 5 As shown in the figure, no local overcurrent will occur.

[0047] The tubular grounding resistor 7 with the stainless steel cylinder 8 as the base is installed in the box through secondary insulation; and the input and output are connected to the grounding carbon brush of the vehicle body grounding system and the vehicle body by a two-time insulation wiring method; wherein, the primary insulation is that the grounding carbon brush is insulated from the input and output terminals 5 of the vehicle body through a primary insulator 20, and the connecting wire of the primary insulator 20 is connected to the lead wire 15 of the ring terminal 17 of the tubular grounding resistor 7, and the lead wire 15 is insulated again by the insulator 11 set under the connecting bracket 9 of the two tubular grounding resistors 7, forming a two-time insulation wiring method. The input and output terminals 5 are installed on the primary insulator 20, and the primary insulator 20 is fixed on the bottom plate 10 of the box body 6. The connecting bracket 9 of the two tubular grounding resistors 7 is installed on the insulator 11, and the insulator 11 is also fixed on the bottom plate 10 of the box body 6, and is surrounded by the side plate 21 and the top plate 19 to form a box (as shown in the attached Figure 4 as shown). Embodiment 2

[0048] The principles of the second embodiment are basically the same as those of the first embodiment, except for the differences in specific structure and processing methods; a grounding resistor for an electric locomotive body grounding system, the grounding resistor is arranged between the grounding carbon brush of the electric locomotive body grounding system and the body; the grounding resistor comprises a resistor body, a wiring terminal and a box body; the wiring terminals are two terminals respectively connected to the two ends of the resistor body, one of the two wiring terminals is connected to the body, and the other is connected to the grounding carbon brush, and the body current is suppressed by the grounding resistor; the resistor body of the grounding resistor is a tubular grounding resistor body.

[0049] The tubular grounding resistor body is just a single elliptical cylinder of stainless steel as the base of the resistor body, forming a tubular grounding resistor body with a hollow metal cylinder as the base, and the grounding carbon brush of the vehicle body grounding system is grounded to the vehicle body through the tubular grounding resistor body with the hollow metal cylinder as the base. The use of the elliptical cylinder can make full use of the space in a limited space to make the tubular grounding resistor body; by adjusting the major and minor axis ratio of the ellipse, one cylinder can be formed in the grounding resistor box to form a tubular grounding resistor body that meets the needs of the entire grounding resistor, so that the space can be fully utilized; and the tubular grounding resistor body with the elliptical cylinder is more convenient to fix than the circular one, and the cylinder is not prone to rotation.

[0050] The tubular grounding resistor with a hollow metal cylinder as the base is an elliptical stainless steel tube as the base. An insulating layer is first compounded on the outer surface of the stainless steel tube, and then a resistor layer is compounded on the insulating layer to form a straight cylindrical resistor body compounded on the outer surface of the elliptical stainless steel tube.

[0051] The resistor body of the tubular grounding resistor body with the metal cylinder as the base is also compounded with a protective layer; the protective layer has a protective film with heat dissipation performance.

[0052] The protective layer is a protective layer formed by a composite of insulating and heat-conducting materials; it includes thermally conductive silicone grease, thermally conductive silica gel, or nano-composite organic silicon material.

[0053] The two ends of the resistor body are connected by an integral ring terminal. The two ends of the tubular grounding resistor body with a metal cylinder as the base are first wrapped with a layer of metal conductive soft pad, and then the tubular grounding resistor body with a metal cylinder as the base is clamped on the metal conductive soft pad by a ring terminal, so that the ring terminal can perform ring-shaped equal resistance conduction as a whole.

[0054] The metal conductive pad is a silver-plated metal braided belt, which is folded into a long strip with the same width as the ring-shaped terminal, and then wrapped around the two ends of the tubular grounding resistor body with the metal cylinder as the base, and the ring-shaped terminal is tightened through the ring-shaped terminal joint, so that the silver-plated metal wire mesh and the resistor body of the tubular grounding resistor body with the metal cylinder as the base are closely fitted together, forming a ring-shaped terminal and the tubular grounding resistor The whole circumference is in contact.

[0055] The tubular grounding resistor with the metal cylinder as the base is installed in the box through secondary insulation, and the input and output are connected to the grounding carbon brush of the vehicle body grounding system and the vehicle body by adopting a double insulation wiring method.

[0056] The metal cylinders are two or more arranged in parallel; and the two or more metal cylinders are connected by connecting brackets at the ends, the metal cylinders and the connecting brackets are connected by laser welding, and then the connecting brackets are fixedly installed on the box of the grounding resistor through insulating parts to form a fixed annular grounding resistor body.

[0057] The thickness of the resistor layer of the tubular grounding resistor with the metal cylinder as the base is determined by calculation according to the needs of the grounding resistance, ensuring that the total resistance value of the tubular grounding resistor with the metal cylinder as the base is the resistance value of the original spiral resistor. Embodiment 3

[0058] The principle of embodiment 3 is basically the same as that of embodiment 1, except for the specific structure and processing method. A grounding resistor for an electric locomotive body grounding system, the grounding resistor is arranged between the grounding carbon brush of the electric locomotive body grounding system and the body; the grounding resistor comprises a resistor body, a wiring terminal and a box body; the wiring terminals are two terminals respectively connected to the two ends of the resistor body, one of the two wiring terminals is connected to the body, and the other is connected to the grounding carbon brush, and the body current is suppressed by the grounding resistor; the resistor body of the grounding resistor is a tubular grounding resistor body.

[0059] The tubular grounding resistor is made of a polygonal aluminum alloy tubular profile to make the base of the resistor, and then the polygonal tubular grounding resistor is wrapped on the polygonal aluminum alloy tubular profile base. The grounding carbon brush of the vehicle body grounding system is grounded to the vehicle body through the polygonal tubular grounding resistor with a hollow metal cylinder as the base. The use of aluminum alloy tubular profiles can further reduce the weight of the cylinder, and the use of polygons can make the tubular grounding resistor easier to fix and easy to identify the direction of the tubular grounding resistor. Since the tubular grounding resistor is made in an open manner, a gap is left between the entire annular cylinder, so when installing, it is necessary to consider whether the installation position can be in a suitable direction to avoid the formation of internal eddy currents; the use of polygonal tubular grounding resistors is easy to identify and install.

[0060] The other parts of this embodiment are the same as those of the previous embodiment.

[0061] The above-listed embodiments are only used to clearly and completely describe the technical solutions of the present invention in combination with the accompanying drawings; it is obvious that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, and the terms such as "upper", "lower", "front", "back", "middle" and so on quoted in this specification are only for the convenience of description, and are not used to limit the scope of the present invention. The change or adjustment of their relative relationship should also be regarded as the scope of the present invention without substantial change in the technical content. At the same time, the structure, proportion, size, etc. illustrated in the drawings of the specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effect and purpose that can be achieved by the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0062] The advantages of the present invention are:

[0063] The present invention adopts a cylindrical resistor to replace the original spiral resistor, which can significantly reduce the weight of the resistor under the same resistance value and eliminate the inductance of the spiral resistor. It has the following advantages:

[0064] 1. Using a hollow ring-shaped resistor to replace the original spiral resistor can greatly reduce the weight of the resistor, which is beneficial to the lightweight of the entire vehicle grounding system;

[0065] 2. The hollow ring-shaped resistor body adopts a thin-walled stainless steel cylinder, which can further reduce the weight of the cylindrical resistor body, thereby further reducing the weight of the entire grounding resistor;

[0066] 3. A resistor is compounded on a hollow ring-shaped stainless steel cylinder, and the resistor is connected to the grounding carbon brush of the vehicle grounding system and the vehicle body through the hollow ring-shaped resistor, which can effectively expand the surface area of ​​the resistor and improve the efficiency of the resistor;

[0067] 4. The hollow ring-shaped resistor is wired in the form of a ring-shaped terminal, and a silver-plated metal braided belt is arranged under the ring-shaped terminal to ensure the overall effect of the hollow ring-shaped resistor and avoid the phenomenon of local short circuit;

[0068] 5. The hollow ring-shaped resistors are supported by stainless steel brackets and connected by laser welding of connecting plates, which has the characteristics of good welding effect and beautiful appearance;

[0069] 6. The hollow ring-shaped resistor is installed on the grounding resistor box through secondary insulation, which has the characteristics of reliable insulation and strong anti-interference ability.

Claims

1. A grounding resistor for an electric locomotive body grounding system, the grounding resistor being arranged between a grounding carbon brush of the electric locomotive body grounding system and the body; the grounding resistor comprising a resistor body, a wiring terminal and a box body; the wiring terminals are two terminals respectively connected to both ends of the resistor body, one of the two wiring terminals is connected to the body, and the other is connected to the grounding carbon brush, and the body current is suppressed by the grounding resistor; the characteristics are: The resistor body of the grounding resistor is a tubular grounding resistor body, and the two ends of the resistor body with a hollow ring-shaped columnar structure are connected through ring-shaped terminals that match the shape of the resistor body with a hollow ring-shaped columnar structure to form input and output connections of the resistor body with a hollow ring-shaped columnar structure; the tubular grounding resistor body is a resistor body with a composite structure and a hollow ring-shaped columnar structure with a metal tube as the matrix, formed by compounding a layer of resistor material on the matrix of a tubular metal cylinder; the metal cylinder is a stainless steel tube, and the resistor body with a hollow ring-shaped columnar structure is compounded on the matrix of the stainless steel tube; an insulating layer is first compounded on the outer surface of the stainless steel tube, and then a resistor layer is compounded on the insulating layer to form a resistor body with a hollow ring-shaped columnar structure with the stainless steel tube as the matrix; the two ends of the resistor body are connected by means of an integral ring-shaped terminal, and a metal conductive pad is provided under the ring-shaped terminal to ensure that the ring-shaped terminal is in overall contact with the tubular grounding resistor body, thereby ensuring the annular tubular The resistance values ​​at both ends of the entire annular surface of the grounding resistor are equipotential; the tubular grounding resistor adopts an open method, leaving a gap on the entire annular cylinder, the width of the gap is 5-10mm, and the gap is filled with an insulating layer material to keep both sides of the gap in an insulating state; the metal conductive pad is connected to the two ends of the resistor body by connecting the integral annular terminal, and one or more layers of silver-plated metal braided belt are first wound around the two ends of the tubular grounding resistor body with the metal cylinder as the base; the silver-plated metal braided belt is stacked into a long strip with the same width as the annular terminal, and then wound around the two ends of the tubular grounding resistor body with the metal cylinder as the base to form a metal conductive pad, and is clamped by the joint bolts of the annular terminal, so that the silver-plated metal wire mesh and the resistor body of the tubular grounding resistor body with the metal cylinder as the base are tightly fitted together, forming a full contact between the annular terminal and the circumference of the tubular grounding resistor body.

2. The grounding resistor for the electric locomotive body grounding system according to claim 1, characterized in that: The metal cylinders are two parallel bodies, and the ends of the two metal cylinders are connected by welding through a metal bracket made of the same material as the cylinder to form a whole, and then the metal bracket is fixed on the box body in an insulating manner.

3. The grounding resistor for the electric locomotive body grounding system according to claim 1, characterized in that: The resistor body of the hollow annular column structure is installed in the box through secondary insulation, and the input and output are connected to the grounding carbon brush of the vehicle body grounding system and the vehicle body by a double insulation wiring method; wherein, the primary insulation is that the grounding carbon brush is insulated from the input and output terminals of the vehicle body through a primary insulator, and the connecting wire of the primary insulator is connected to the lead wire of the annular terminal of the tubular grounding resistor body, and the lead wire is insulated again by an insulator arranged under the connecting bracket of the two tubular grounding resistor bodies, forming a double insulation wiring method; the input and output terminals are installed on the primary insulator, the primary insulator is fixed on the bottom plate of the box, the connecting brackets of the two tubular grounding resistor bodies are installed on the insulator, and the insulator is also fixed on the bottom plate of the box, and is surrounded by side plates and a top plate to form a box.

4. The grounding resistor for the electric locomotive body grounding system according to claim 1, characterized in that: A protective layer is also compounded on the resistance layer; the protective layer is a protective film with heat dissipation performance.

5. The grounding resistor for the electric locomotive body grounding system according to claim 4, characterized in that: The protective layer is a protective layer formed by a composite of insulating and heat-conducting materials; it includes thermally conductive silicone grease, thermally conductive silica gel, or nano-composite organic silicon material.

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