A ring main unit cabinet body forming and welding device

Abstract

This invention relates to the field of cabinet welding technology, and in particular to a ring main unit cabinet forming and welding device; it includes a fixing mechanism for docking and fixing the cabinet and a robotic arm located on its front side; the driving end of the robotic arm is provided with a welding mechanism; this invention effectively solves the three major technical problems of easy gas loss at the edge, lack of fusion due to assembly gaps, and significant welding thermal deformation by means of the synergistic effect of the cone-shaped air curtain formed by the trumpet-shaped nozzle, the auxiliary block extending the attachment plane, the driving component driving the auxiliary block to dynamically compensate for the gap, and the cooling block implementing forced cooling.

Description

Technical Field

[0001] This invention relates to the field of cabinet welding technology, and in particular to a ring main unit cabinet forming and welding device. Background Technology

[0002] A ring main unit (RMU) is a metal-enclosed high-voltage switchgear used for power distribution and protection control in 10kV power distribution systems. Its cabinet typically consists of key functional compartments such as a switch compartment, fuse compartment, operating mechanism compartment, and cable compartment. To ensure long-term reliability and safety, the RMU cabinet must possess extremely high structural strength, dimensional accuracy, and provide a fully sealed protective environment for internal electrical components. This places stringent requirements on the connection process between the thin steel plates that make up the cabinet. Welding is the core manufacturing method for achieving the cabinet structure, ensuring its overall rigidity, and achieving high standards of airtightness. Modern production commonly uses arc welding robots combined with advanced welding technologies such as CMT (cold metal transfer) to complete the cabinet assembly.

[0003] However, the following problems exist in the current welding process: First, when welding is performed at open edges of the cabinet, the lack of an effective physical adhesion boundary makes the shielding gas prone to turbulence and rapid dissipation, leading to arc protection failure. The molten pool is susceptible to air intrusion, resulting in oxidation and porosity, which seriously damages the density and sealing integrity of the weld. Second, due to the microscopic gaps in the assembly of thin plates and the slight unevenness of the plates themselves, these gaps change dynamically during the welding process. Traditional rigid tooling cannot compensate for this in real time, causing linear defects such as incomplete fusion and incomplete penetration at the weld root due to uneven heat input, forming potential leakage channels. Finally, the concentrated heat input of the welding arc generates uneven heat circulation in the local area of ​​the thin plate. The resulting welding residual stress causes plastic deformation such as warping and wavy deformation of the cabinet plates that exceeds the tolerance range. This deformation directly damages the dimensional accuracy of the cabinet and the flatness of the sealing assembly surface, affecting the final product's assembly quality and long-term sealing reliability.

[0004] Therefore, the problems that need to be solved by those skilled in the art include: the protective gas easily dissipates at the edges and corners of the cabinet, leading to protection failure; the inability to dynamically compensate for the gaps in the assembly of thin plates during welding, resulting in incomplete weld fusion; and the concentrated welding heat input causing uncontrollable deformation of the thin plate cabinet, which in turn affects the weld sealing performance, connection reliability, and structural accuracy. Summary of the Invention

[0005] In view of the above problems, the present invention provides a ring main unit cabinet forming and welding device to solve the aforementioned technical problems.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a ring main unit cabinet forming and welding device, comprising a fixing mechanism for docking and fixing the cabinet and a robotic arm located on its front side; the driving end of the robotic arm is provided with a welding mechanism.

[0007] The welding mechanism includes a fixed plate fixedly mounted on a robotic arm, a welding gun fixedly mounted on the fixed plate, a nozzle fixedly mounted on the welding gun, an auxiliary stop block slidably mounted on the fixed plate via a pair of support plates, a cooling block provided at the right end of the auxiliary stop block, and a driving component for driving the auxiliary stop block to move on the fixed plate.

[0008] When the welding mechanism is working, it first drives the auxiliary stop block through the drive component to press its working surface against the outer panel of the cabinet to extend the physical plane of the weld edge. At the same time, the nozzle sprays air to form a conical air curtain. The conical air curtain adheres and flows stably along the plane extended by the auxiliary stop block, forming a complete gas protection environment. As the robotic arm moves the welding torch along the weld trajectory, the auxiliary stop block and the cooling block move synchronously to maintain the compression and adhesion boundary of the panel surface, while the cooling block provides forced cooling to the back of the weld.

[0009] As a preferred embodiment, the driving component includes a connecting plate fixedly installed at the rear end of the fixed plate, a cylinder fixedly installed at the front end of the connecting plate, a connecting block fixedly installed between the two support plates, and the telescopic section of the cylinder fixedly connected to the connecting block.

[0010] As a preferred embodiment, the cooling block has a serpentine flow channel inside for coolant flow, and an outlet pipe and an inlet pipe are fixedly installed at the front end of the cooling block, which are respectively connected to the upper and lower ends of the flow channel.

[0011] As a preferred embodiment, the nozzle has a frustum-shaped structure with a lower diameter larger than the upper diameter, and the nozzle is also a hollow tubular structure. An annular air hole is opened at the lower end of the nozzle, and an air inlet pipe communicating with its hollow inner cavity is fixedly installed on the outer wall of the nozzle.

[0012] As a preferred embodiment, a plurality of heat-conducting rollers are rotatably mounted on the end of the cooling block away from the auxiliary stop.

[0013] As a preferred embodiment, the heat-conducting roller shaft has a hollow structure inside, through which the coolant flows to achieve heat exchange.

[0014] As a preferred embodiment, a liquid storage box is fixedly installed at the lower end of the cooling block, the lower end of the heat-conducting roller shaft rotates through into the liquid storage box, and the lower end of the heat-conducting roller shaft is connected to the inside of the liquid storage box, and an inlet and outlet pipe is connected to the front end of the liquid storage box.

[0015] As a preferred embodiment, the outer edge of the annular vent is chamfered.

[0016] The above-described one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0017] I. This invention effectively solves three major technical problems: gas protection is easily lost at the edges, assembly gaps lead to incomplete fusion, and welding thermal deformation is significant. This is achieved through the synergistic effect of forming a conical air curtain with a trumpet-shaped nozzle, extending the attachment plane with auxiliary blocks, driving the auxiliary blocks to dynamically compensate for gaps, and implementing forced cooling with cooling blocks. As a result, it comprehensively improves the sealing reliability, connection integrity, and structural dimensional accuracy of the ring main unit's weld seams.

[0018] Second, this invention forms a conical air curtain covering the welding area through the unique expansion structure of the nozzle and the annular air hole, while the driveable auxiliary block provides a stable adhesion plane for the air curtain. The combination of the two allows the protective gas to stably cover the edge of the cabinet, solving the technical problem of the protective gas becoming disordered and escaping at this position due to the lack of an adhesion boundary, thereby effectively preventing the oxidation of the molten pool and porosity defects caused by this.

[0019] Third, the present invention uses a drive component to drive an auxiliary stop block to press the plate surface, which can adapt to and compensate for the micro-assembly gap of the plate in real time; at the same time, the cooling block uses its internal serpentine flow channel and heat-conducting roller shaft to perform rolling contact forced cooling on the back of the weld, so as to solve the problem of root non-fusion caused by dynamic changes in the gap, and the problem of plate warping and deformation caused by local high heat input, thereby ensuring the continuous fusion of the weld and the shape stability of the cabinet structure.

[0020] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0022] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0023] Figure 2 This is a schematic diagram of the structure of the driving component of the present invention.

[0024] Figure 3 This is a schematic diagram of the welding mechanism of the present invention.

[0025] Figure 4 for Figure 3 Enlarged view of the structure at point A in the image.

[0026] Figure 5This is a schematic diagram of the nozzle structure after cross-section according to the present invention.

[0027] Figure 6 for Figure 5 Enlarged view of the structure at point B in the middle.

[0028] Figure 7 This is a schematic diagram of the serpentine flow channel of the present invention.

[0029] Reference numerals: 10, fixing mechanism; 100, base; 101, spindle box; 102, fixing frame; 11, robotic arm; 2, welding mechanism; 20, welding torch; 21, nozzle; 210, annular vent; 22, auxiliary stop block; 23, cooling block; 230, serpentine flow channel; 231, liquid outlet pipe; 232, liquid inlet pipe; 233, heat-conducting roller shaft; 234, liquid storage box; 235, inlet and outlet pipes; 3, driving component; 30, connecting plate; 31, cylinder; 32, connecting block. Detailed Implementation

[0030] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0031] like Figure 1 As shown, a ring main unit cabinet forming and welding device includes a fixing mechanism 10 for docking and fixing the cabinet and a robotic arm 11 located on its front side; the fixing mechanism 10 includes a base 100 fixedly installed on the ground, and two spindle boxes 101 distributed left and right on the base 100. The left spindle box 101 is fixedly installed on the upper end of the base 100, and the right spindle box 101 is slidably installed on the upper end of the base 100. The driving ends of the two spindle boxes 101 facing each other are equipped with fixing frames 102. The driving end of the robotic arm 11 is equipped with a welding mechanism 2. The fixing mechanism 10 and the robotic arm 11 are existing technologies and are not the design points of this invention, so they will not be described in detail.

[0032] like Figure 1 , Figure 2 and Figure 3 As shown, the welding mechanism 2 includes a fixed plate fixedly mounted on the robotic arm 11, a welding torch 20 fixedly mounted on the fixed plate, a nozzle 21 fixedly mounted on the welding torch 20, an auxiliary stop 22 slidably mounted on the fixed plate via a pair of support plates, and the auxiliary stop 22 is located on the left side of the welding torch 20. A cooling block 23 is provided at the right end of the auxiliary stop 22, and a driving component 3 for driving the auxiliary stop 22 to move is provided on the fixed plate.

[0033] like Figure 2 and Figure 3 As shown, the driving component 3 includes a connecting plate 30 fixedly installed at the rear end of the fixed plate, a cylinder 31 fixedly installed at the front end of the connecting plate 30, a connecting block 32 fixedly installed between the two support plates, and the telescopic section of the cylinder 31 is fixedly connected to the connecting block 32.

[0034] like Figure 3 , Figure 5 and Figure 6 As shown, the nozzle 21 has a frustum-shaped structure with a lower diameter larger than the upper diameter, and the nozzle 21 is also a hollow tubular structure. An annular air hole 210 is provided at the lower end of the nozzle 21, and an air inlet pipe communicating with its hollow inner cavity is fixedly installed on the outer wall of the nozzle 21.

[0035] like Figure 5 and Figure 6 As shown, the outer edge of the annular vent 210 is chamfered.

[0036] like Figures 1 to 6 As shown, during actual operation, the adjustable spindle box 101 of the fixing mechanism 10 and the fixing frame 102 accurately align and firmly lock the cabinet plate. Before welding starts, the robotic arm 11 first drives the welding mechanism 2 to position, so that the auxiliary stop 22 and the integrated cooling block 23 move to the predetermined position outside the weld edge. Then, the driving component 3 pushes the auxiliary stop 22, so that the working surface of the cooling block 23 presses against the outer plate surface of the cabinet, improving the fit of the welding position and extending the physical plane of the weld edge, creating a key adhesion boundary for the subsequent formation of a stable gas flow field.

[0037] Next, the shielding gas is introduced and ejected through the unique trumpet-shaped nozzle 21 on the welding torch 20. The expansion structure at the lower end of the nozzle 21 and the inner chamfer design of the annular vent 210 work together to organize the airflow into an expanding, laminar-dominated conical air curtain. When the conical air curtain reaches the plane extended by the auxiliary baffle 22, it can stably adhere to this plane and flow downstream, thereby creating a complete and closed gas protection environment at the edge of the open weld. This conical air curtain reduces the entrainment of surrounding air due to violent turbulence. At the same time, this stable conical air curtain forms a dynamic pressure and momentum balance zone with the external ambient airflow, which can effectively dissipate and deflect external disturbances, forming a flexible air curtain barrier to ensure that external air cannot enter its interior. This provides a stable external environment for the finer inner shielding gas area directly below the welding torch 20, thereby avoiding contamination and dilution of the shielding gas and the resulting oxidation of the molten pool.

[0038] In addition, the conical air curtain continuously expands outward at a low speed, forming a continuous airflow sweeping zone while covering the welding area. This effectively blows away the slight dust, moisture, and some free metal vapor generated by the electric arc at the welding front, creating a cleaner substrate surface and a more stable arc space for welding. Furthermore, the exchange between the airflow and the surrounding air also removes some of the radiant heat from the welding area, providing an auxiliary heat dissipation effect.

[0039] After completing the above preparations and confirming the formation of a stable air curtain, the welding process officially begins: the robotic arm 11 moves the welding torch 20 along the weld seam trajectory to perform welding. At the same time, the auxiliary stop block 22 moves accordingly to maintain the pressure on the plate surface and create an attachment boundary in the corresponding area. Meanwhile, the cooling block 23 follows the welding torch 20 to synchronously force-cool the back of the weld seam to control deformation.

[0040] The entire process systematically solves problems such as edge protection and thermal deformation control by first establishing an attachment plane and a stable air curtain, and then performing welding and cooling, thus achieving high-quality welding.

[0041] like Figure 3 , Figure 4 and Figure 7 As shown, the cooling block 23 has a serpentine flow channel 230 inside for coolant flow, and the front end of the cooling block 23 is fixedly installed with an outlet pipe 231 and an inlet pipe 232 that are respectively connected to the upper and lower ends of the flow channel.

[0042] like Figure 3 and Figure 4 As shown, a plurality of heat-conducting rollers 233 are rotatably mounted on the end of the cooling block 23 away from the auxiliary stop block 22.

[0043] like Figure 4 As shown, the heat-conducting roller shaft 233 has a hollow structure inside, through which the coolant flows to achieve heat exchange.

[0044] like Figure 3 and Figure 4 As shown, a liquid storage box 234 is fixedly installed at the lower end of the cooling block 23. The lower end of the heat-conducting roller shaft 233 rotates through into the liquid storage box 234, and the lower end of the heat-conducting roller shaft 233 is connected to the inside of the liquid storage box 234. An inlet and outlet pipe 235 is connected to the front end of the liquid storage box 234.

[0045] like Figure 3 , Figure 4 and Figure 7As shown, during actual operation, the low-temperature coolant from the external system is pumped in through the inlet pipe 232 fixed to the front end of the cooling block 23 and directly enters the serpentine flow channel 230 inside the cooling block 23. When the coolant flows through the serpentine flow channel 230, it absorbs and carries away some of the heat conducted from the welding area by the auxiliary baffle 22 and the cooling block 23 itself through heat conduction with the cooling block 23. After the initial heat exchange is completed, the coolant temperature rises and is then discharged through the outlet pipe 231 at the front end of the cooling block 23, returning to the external system for cooling.

[0046] Meanwhile, another stream of coolant is injected into the reservoir 234 through the inlet / outlet pipe 235 connected to the front end of the reservoir 234, filling it with coolant. Since the lower ends of all the heat-conducting rollers 233 rotate through the reservoir 234 and their cavities are connected to the interior of the reservoir 234, the coolant in the reservoir 234 can directly and quickly fill the hollow cavity of each heat-conducting roller 233. During welding, the coolant-filled heat-conducting rollers 233 roll in contact with the back of the high-temperature weld, reducing friction. The welding heat is rapidly conducted to the wall of the heat-conducting roller 233 through the contact point and immediately cooled by the coolant flowing within its cavity. Liquid absorption; the system continuously and rapidly pumps and replenishes the coolant in the roller cavity by controlling the pump pressure of the inlet and outlet pipes 235 of the liquid storage box 234. That is, the liquid that has absorbed heat and heated up is pumped back from the roller cavity to the liquid storage box 234 and discharged through the inlet and outlet pipes 235. At the same time, new low-temperature coolant is replenished from the inlet and outlet pipes 235 to the liquid storage box 234 and injected into the roller cavity, ensuring that the inside of the roller is always filled with low-temperature coolant with high-efficiency heat exchange. The main circulation of the serpentine flow channel 230 of the cooling block 23 and the secondary circulation of the roller and the liquid storage box 234 work together to achieve a continuous, uniform and efficient composite cooling effect on the weld area.

[0047] In addition, the cooling block 23 and the heat-conducting roller shaft 233 can be made of aluminum nitride ceramic blocks, which have extremely high thermal conductivity, ensuring that the welding heat can be dissipated instantly and efficiently, realizing rapid and strong cooling of the weld area and effectively suppressing the thermal deformation of the thin plate; at the same time, its excellent wear resistance and high temperature stability ensure the dimensional accuracy and functional reliability of this key component in long-term sliding or rolling contact with high-temperature workpieces, avoiding cooling failure caused by wear, thermal fatigue or performance degradation, thereby ensuring the durability and consistency of deformation control effect throughout the welding process.

[0048] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0049] Furthermore, the terms "first," "second," "number one," and "number two" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," "number one," or "number two" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "connected," "installed," and "connected" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0051] The embodiments described herein are preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A ring main unit cabinet forming and welding device, comprising a fixing mechanism for docking and fixing the cabinet body and a robotic arm located at its front side; characterized in that: The robotic arm drive end is equipped with a welding mechanism; The welding mechanism includes a fixed plate fixedly mounted on a robotic arm, a welding gun fixedly mounted on the fixed plate, a nozzle fixedly mounted on the welding gun, an auxiliary stop block slidably mounted on the fixed plate via a pair of support plates, a cooling block provided at the right end of the auxiliary stop block, and a driving component for driving the auxiliary stop block to move on the fixed plate. When the welding mechanism is working, it first drives the auxiliary stop block through the drive component to press its working surface against the outer panel of the cabinet to extend the physical plane of the weld edge. At the same time, the nozzle sprays air to form a conical air curtain. The conical air curtain adheres and flows stably along the plane extended by the auxiliary stop block, forming a complete gas protection environment. As the robotic arm moves the welding torch along the weld trajectory, the auxiliary stop block and the cooling block move synchronously to maintain the compression and adhesion boundary of the panel surface, while the cooling block provides forced cooling to the back of the weld.

2. The ring main unit cabinet forming and welding device according to claim 1, characterized in that: The driving component includes a connecting plate fixedly installed at the rear end of the fixed plate, a cylinder fixedly installed at the front end of the connecting plate, a connecting block fixedly installed between the two support plates, and the telescopic section of the cylinder fixedly connected to the connecting block.

3. The ring main unit cabinet forming and welding device according to claim 1, characterized in that: The cooling block has a serpentine flow channel inside for coolant flow, and an outlet pipe and an inlet pipe are fixedly installed at the front end of the cooling block, which are respectively connected to the upper and lower ends of the flow channel.

4. The ring main unit cabinet forming and welding device according to claim 1, characterized in that: The nozzle has a frustum-shaped structure with a lower diameter larger than the upper diameter, and it is also a hollow tubular structure. An annular air hole is opened at the lower end of the nozzle, and an air inlet pipe communicating with its hollow inner cavity is fixedly installed on the outer wall of the nozzle.

5. The ring main unit cabinet forming and welding device according to claim 1, characterized in that: Multiple heat-conducting rollers are rotatably mounted on the end of the cooling block away from the auxiliary stop.

6. The ring main unit cabinet forming and welding device according to claim 5, characterized in that: The heat-conducting roller shaft has a hollow structure inside, through which the coolant flows to achieve heat exchange.

7. The ring main unit cabinet forming and welding device according to claim 6, characterized in that: A liquid storage box is fixedly installed at the lower end of the cooling block. The lower end of the heat-conducting roller shaft rotates through the liquid storage box and is connected to the inside of the liquid storage box. An inlet and outlet pipe is connected to the front end of the liquid storage box.

8. The ring main unit cabinet forming and welding device according to claim 4, characterized in that: The outer edge of the annular vent is chamfered.

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