An explosion-proof oil-filling structure for an explosion-proof electrical cabinet

Abstract

This invention relates to the field of explosion-proof technology, and in particular to an explosion-proof oil-filled structure for explosion-proof electrical cabinets. The structure includes an oil inlet valve and an oil outlet valve. The oil inlet valve is connected to the top wall of the explosion-proof electrical cabinet, and the oil outlet valve is connected to the lower end of the cabinet. A base plate is placed on the explosion-proof electrical cabinet, and an air pump is mounted on the base plate. The air inlet of the air pump is connected to a nitrogen storage device. A connecting pipe is placed inside the oil inlet valve, and the connecting pipe is connected to an air filling pipe and an oil filling pipe via an adjusting mechanism. The air filling pipe is connected to the air outlet of the air pump, and the oil filling pipe is connected to the pump body. This invention allows air to be discharged from the explosion-proof electrical cabinet, thereby preventing oxygen from affecting the insulating oil and ensuring the cooling and insulation effects of the insulating oil.

Description

Technical Field

[0001] This invention relates to the field of explosion-proof technology, and in particular to an explosion-proof oil-filled structure for explosion-proof electrical cabinets. Background Technology

[0002] Explosion-proof electrical cabinets, also known simply as explosion-proof cabinets, are low-voltage power distribution units constructed by assembling switching equipment, measuring instruments, protective electrical devices, and auxiliary equipment in a closed or semi-closed metal cabinet or panel according to electrical wiring requirements. These cabinets are made of steel and are used to protect the components and ensure their proper functioning. Explosion-proof electrical cabinets are often used in production environments containing explosive gases. During operation, these cabinets inevitably generate electrical sparks. If these sparks come into contact with explosive gases in the production environment, an explosion can occur. To prevent the generation of these sparks, insulating oil is injected into the explosion-proof electrical cabinet. The insulating oil acts as an arc extinguisher, preventing the generation of sparks, and also helps to cool and absorb heat from the internal electrical components.

[0003] When filling general equipment with insulating oil, the insulating oil is first degassed using a vacuum oil filter to remove air. Then, the air inside the equipment is extracted by vacuuming. However, since explosion-proof gas-insulated cabinets are generally made of cold-rolled steel plates, although they have a certain thickness, if vacuuming is used, the external atmospheric pressure will cause the explosion-proof gas-insulated cabinet to deform and be damaged. Therefore, if vacuuming is not performed, the insulating oil will come into contact with the air inside the explosion-proof gas-insulated cabinet when it is injected. This causes oxygen from the air to mix into the insulating oil. The contact between the insulating oil and oxygen will cause thermal oxidation and aging. In addition to producing water and odor, it will also form acid and sludge, which will cause sludge to accumulate on the surface of the internal protective electrical components of the explosion-proof electrical cabinet, affecting the cooling effect and reducing the insulation strength. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies where oxygen is mixed into the insulating oil, leading to reduced cooling effect and weakened insulation strength. This invention proposes an explosion-proof oil-filled structure for explosion-proof electrical cabinets.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] Design an explosion-proof oil-filled structure for an explosion-proof electrical cabinet, including an oil inlet valve and an oil outlet valve. The oil inlet valve is connected to the top wall of the explosion-proof electrical cabinet, and the oil outlet valve is connected to the lower end of the explosion-proof electrical cabinet.

[0007] The explosion-proof electrical cabinet is equipped with a base plate, and an air pump is installed on the base plate. The air pump inlet is connected to a nitrogen storage device. A connecting pipe is placed inside the oil inlet valve. The connecting pipe is connected to an air filling pipe and an oil filling pipe through an adjustment mechanism. The air filling pipe is connected to the air outlet of the air pump.

[0008] The oil filling pipe is connected to the pump body.

[0009] Preferably, a connecting block is fixedly connected to the connecting pipe, and a sealing gasket is provided on the side of the connecting block opposite to the oil inlet valve. The sealing gasket is used to seal the oil inlet valve, and a telescopic rod is provided between the connecting block and the base plate.

[0010] Preferably, the adjusting mechanism includes a connecting shell, a threaded hole, a sealing ring, a rotating shaft, and a moving block. The connecting shell is connected to the oil filling pipe and the air filling pipe respectively, and is perpendicularly connected to the connecting pipe. The moving block is disposed inside the connecting shell, and the sealing ring is fixedly connected to both ends of the moving block. Both sealing rings abut against the inner wall of the connecting shell. The moving block has a threaded hole, and the rotating shaft has an external thread that is threadedly connected to the threaded hole. One end of the rotating shaft extends out of the connecting shell, and the connecting shell and the rotating shaft are rotatably connected by a sealed bearing.

[0011] Preferably, both the inner cavity of the connecting shell and the moving block have a rectangular structure.

[0012] Preferably, a gear is fixedly connected to the rotating shaft, and a rack is fixedly connected to the base plate, with the rack meshing with the gear.

[0013] Preferably, the inner ring wall of the sealing ring is provided with multiple connecting holes, and multiple limiting blocks are fixedly connected to the moving block, the limiting blocks being able to be inserted into the connecting holes.

[0014] Preferably, the connecting hole is a blind hole.

[0015] Preferably, both the connecting shell and the inner wall of the oil filling pipe are provided with a non-stick layer.

[0016] Preferably, the sealing ring is a PU (polyurethane) rubber sealing ring.

[0017] The present invention proposes an explosion-proof oil-filled structure for explosion-proof electrical cabinets. The beneficial effects are as follows: the introduction of nitrogen into the explosion-proof electrical cabinet allows the air inside to be expelled, thereby preventing the oxygen in the air from affecting the insulating oil and ensuring the cooling and insulation effects of the insulating oil. At the same time, because the introduction of nitrogen replaces the air, it ensures that the internal and external pressures of the explosion-proof electrical cabinet are consistent, preventing the explosion-proof electrical cabinet from being squeezed and deformed due to vacuuming. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of an explosion-proof oil-filled structure for an explosion-proof electrical cabinet proposed in this invention.

[0019] Figure 2 This invention proposes a three-dimensional explosion-proof oil-filled structure for explosion-proof electrical cabinets. Figure 1 ;

[0020] Figure 3 This invention proposes a three-dimensional explosion-proof oil-filled structure for explosion-proof electrical cabinets. Figure 2 ;

[0021] Figure 4 This is a perspective view (shell section) of an explosion-proof oil-filled structure for an explosion-proof electrical cabinet proposed in this invention;

[0022] Figure 5 This invention proposes an explosion-proof oil-filled structure for explosion-proof electrical cabinets. Figure 4 The front view;

[0023] Figure 6 This is a schematic diagram of the sealing ring portion of an explosion-proof oil-filled structure for an explosion-proof electrical cabinet, as proposed in this invention.

[0024] In the diagram: 1. Oil outlet valve; 2. Oil inlet valve; 3. Base plate; 4. Air pump; 5. Telescopic rod; 6. Connecting block; 7. Sealing gasket; 8. Connecting pipe; 9. Connecting shell; 10. Oil filling pipe; 11. Air filling pipe; 12. Gear; 13. Rack; 14. Threaded hole; 15. Sealing ring; 16. Rotating shaft; 17. Moving block; 18. Limiting block. Detailed Implementation

[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0026] Example 1

[0027] Reference Figure 1-5 An explosion-proof oil-filled structure for an explosion-proof electrical cabinet includes an oil inlet valve 2 and an oil outlet valve 1. The oil inlet valve 2 is connected to the top wall of the explosion-proof electrical cabinet, and the oil outlet valve 1 is connected to the bottom of the explosion-proof electrical cabinet. The oil inlet valve 2 is located at the top. Since the density of nitrogen is less than that of air when nitrogen is injected, the nitrogen will float above the air. By injecting nitrogen through the oil inlet valve 2, the nitrogen floating above the air will squeeze the air out through the oil outlet valve 1 at the bottom.

[0028] An explosion-proof electrical cabinet is equipped with a base plate 3, on which an air pump 4 is installed. The air inlet of the air pump 4 is connected to a nitrogen storage device. A connecting pipe 8 is placed inside the oil inlet valve 2. The connecting pipe 8 is connected to an air filling pipe 11 and an oil filling pipe 10 through an adjustment mechanism. The air filling pipe 11 and the oil filling pipe 10 are flexible hoses for bending and folding. The air filling pipe 11 is connected to the air outlet of the air pump 4. Nitrogen is injected into the explosion-proof electrical cabinet through the air filling pipe 11 by the air pump 4, so that the air in the explosion-proof electrical cabinet is discharged, preventing oxygen from contacting the insulating oil. This avoids the influence of oxygen on the insulating oil, ensuring the cooling and insulation effects. At the same time, the injection of nitrogen replaces the air, thus ensuring that the internal and external pressures of the explosion-proof electrical cabinet are consistent, preventing the explosion-proof electrical cabinet from being squeezed and deformed due to vacuuming.

[0029] The oil filling pipe 10 is connected to the pump body. The insulating oil is first degassed and filtered, and then transported into the explosion-proof electrical cabinet by the pump body.

[0030] Example 2

[0031] In Example 1, because nitrogen is less dense than air during nitrogen injection, some of the nitrogen entering through inlet valve 2 rises, causing it to be discharged from inlet valve 2. This increases the amount of nitrogen being injected, resulting in nitrogen waste. (Refer to...) Figure 2-5 In another preferred embodiment of the present invention, based on embodiment 1, a connecting block 6 is fixedly connected to the connecting pipe 8. A sealing gasket 7 is provided on the side of the connecting block 6 opposite to the oil inlet valve 2. The sealing gasket 7 is used to seal the oil inlet valve 2. A telescopic rod 5 is provided between the connecting block 6 and the base plate 3. When nitrogen is filled, the telescopic rod 5 is contracted to press the sealing gasket 7 against the oil inlet valve 2, thus avoiding nitrogen overflow and waste. At the same time, the telescopic rod 5 provides support for the connecting block 6 and the connecting pipe 8.

[0032] Example 3

[0033] In Example 2, the gas filling pipe 11 and oil filling pipe 10 are controlled by a regulating machine to control the filling of nitrogen gas and insulating oil. Generally, valves are used for control. Since the filling of nitrogen gas and oil are two separate steps, two valves are required for control. One valve needs to be opened and the other closed. Both valves need to be turned each time. After filling nitrogen gas, the valve on the gas filling pipe 11 needs to be closed. If the valve on the gas filling pipe 11 is not closed, when filling oil, the oil will enter the gas filling pipe 11 due to the open valve and remain there. This will lead to waste of insulating oil after the oil filling is completed.

[0034] Reference Figure 4-5In another preferred embodiment of the present invention, based on embodiment 2, the adjustment mechanism includes a connecting shell 9, a threaded hole 14, a sealing ring 15, a rotating shaft 16, and a moving block 17. The connecting shell 9 is connected to the oil filling pipe 10 and the air filling pipe 11 respectively, and the connecting shell 9 is perpendicularly connected to the connecting pipe 8. The moving block 17 is disposed inside the connecting shell 9, and both ends of the moving block 17 are fixedly connected to the sealing rings 15. Both sealing rings 15 abut against the inner wall of the connecting shell 9. By moving the moving block 17 in the connecting shell 9, the sealing rings 15 seal one end of the connecting shell 9, and the other end is connected to the connecting pipe 8, which replaces the use of two valves. Only one adjustment is needed, which increases the convenience of operation. At the same time, when filling oil, the air filling pipe 11 will not be unsealed, thereby avoiding the situation where insulating oil enters the air filling pipe 11 due to the use of two valves, resulting in waste of insulating oil.

[0035] The movable block 17 has a threaded hole 14, and the rotating shaft 16 has an external thread. The external thread is threaded to the threaded hole 14. One end of the rotating shaft 16 extends into a connecting shell 9. The connecting shell 9 and the rotating shaft 16 are rotatably connected by a sealed bearing. By rotating the rotating shaft 16, the position of the adjusting threaded hole on the rotating shaft 16 is adjusted, thereby driving the movable block 17 to move, changing the position of the sealing ring 15, and changing the conductive state of the connecting shell 9.

[0036] Both the inner walls of the connecting shell 9 and the oil filling pipe 10 are provided with a non-stick layer, which can be made of polytetrafluoroethylene. Since the insulating oil passes through the connecting shell 9 and the oil filling pipe 10, the non-stick layer design helps to avoid the insulating oil remaining in the connecting shell 9 and the oil filling pipe 10, thus avoiding waste.

[0037] Example 4

[0038] In embodiment 3, the rotating shaft 16 is driven to rotate by rotation. Generally, for fluid flow, the connecting shell 9 is designed to be cylindrical. However, when the rotating shaft 16 rotates, the moving block 17 is easily caused to rotate, preventing it from moving and thus preventing changes to the conductivity. (Refer to...) Figure 4-5 As another preferred embodiment of the present invention, based on embodiment 3, both the inner cavity of the connecting shell 9 and the moving block 17 are rectangular structures. By adopting the rectangular structure design, a limiting function is played to prevent the moving block 17 from rotating when the rotating shaft 16 is rotated, thereby ensuring that the moving block 17 can move.

[0039] Example 5

[0040] In embodiment 4, the conductivity of the connecting shell 9 is changed by moving the movable block 17. However, because the movable block 17 is located inside the shell 9, the position of the sealing ring 15 cannot be observed. When such a situation occurs... Figure 4 and Figure 5 When the position is shown, the sealing ring 15 will simultaneously seal both ends of the housing 9. This will cause the air pressure near the inflation tube 11 of the housing 9 to gradually increase during inflation, which will generate a huge thrust on the sealing ring 15. The threaded hole 14 is supported by the external threaded connection. When the threaded connection is too short, it will cause damage to the threaded connection, making it impossible to adjust the position of the moving block 17. Furthermore, when rotating the shaft 16, the threaded hole 14 may disengage from the external thread, which will also prevent the moving block 17 from being adjusted and cause the adjustment mechanism to malfunction.

[0041] Reference Figure 2-5 In another preferred embodiment of the present invention, based on embodiment 4, a gear 12 is fixedly connected to the rotating shaft 16, and a rack 13 is fixedly connected to the base plate 3. The rack 13 meshes with the gear 12. When the telescopic rod 5 retracts and the sealing gasket 7 abuts against the oil inlet valve 2, this is the nitrogen filling stage. This drives the gear 12 to move and rotate on the rack 13, causing the rotating shaft 16 to rotate. This adjusts the position of the rotating shaft 16 in the threaded hole 14, causing the moving block 17 to move. After the sealing is completed, the moving block 17 will move along... Figure 5 The position is moved to the right to ensure the connection between the connecting pipe 8 and the inflation pipe 11. When filling with oil, the sealing gasket 7 needs to be opened to allow nitrogen to escape during filling. The telescopic rod 5 extends, driving the gear 12 to move and rotate on the rack 13, which in turn drives the rotating shaft 16 to rotate. Adjusting the position of the rotating shaft 16 in the threaded hole 14 moves the moving block 17. The moving block 17 moves along... Figure 5 The position of the telescopic rod 5 is moved to the left to ensure the connection between the connecting pipe 8 and the oil filling pipe 10. When the telescopic rod 5 is retracted to its lowest point, the adjustment mechanism is connected for inflation. When the telescopic rod 5 is raised to its highest point, the adjustment mechanism is connected for oil filling. This ensures the state of the adjustment mechanism and prevents the housing 9 from being blocked by the sealing ring 15 during inflation, which could damage the threaded connection. It also limits the distance that the rotating shaft 16 can move in the threaded hole 14, preventing the threaded hole 14 from separating from the external thread on the rotating shaft 16. Furthermore, since the adjustment mechanism is adjusted by changing the state of the telescopic rod 5 to connect for inflation or oil filling, no manual operation is required, increasing the convenience of operation.

[0042] During use, the connecting pipe 8 is inserted into the oil inlet valve 2, the telescopic rod 5 retracts, and the sealing gasket 7 abuts against the oil inlet valve 2. Simultaneously, as the telescopic rod 5 retracts, it drives the gear 12 to rotate on the rack 13, causing the rotating shaft 16 to rotate. Adjusting the position of the rotating shaft 16 in the threaded hole 14 moves the moving block 17, connecting the connecting pipe 8 to the air filling pipe 11 for nitrogen filling. The nitrogen is discharged from the oil outlet valve 1. After completion, the oil outlet valve 1 is closed. Then, the telescopic rod 5 extends, and the sealing gasket 7 moves away from the oil inlet valve 2. Simultaneously, the telescopic rod 5 extends, driving the gear 12 to rotate on the rack 13, causing the rotating shaft 16 to rotate. Adjusting the position of the rotating shaft 16 in the threaded hole 14 moves the moving block 17. The sealing ring 15 seals the other end of the connecting shell 9, connecting the connecting pipe 8 to the oil filling pipe 10. Insulating oil is filled through the pump body, and nitrogen is discharged from the oil inlet valve 2. After filling, the oil inlet valve 2 is closed.

[0043] Example 6

[0044] In embodiment 5, since sealing is achieved through the sealing ring 15, which is located on the moving block 17, there is significant friction between the sealing ring 15 and the housing 9. This friction affects the connection between the moving block 17 and the sealing ring 15 when the moving block 17 moves. (Refer to...) Figure 6 In another preferred embodiment of the present invention, based on embodiment 5, the inner ring wall of the sealing ring 15 is provided with multiple connecting holes, and multiple limiting blocks 18 are fixedly connected to the moving block 17. The limiting blocks 18 can be inserted into the connecting holes. The connecting holes are blind holes. The blind hole design prevents the limiting blocks 18 from being exposed, thereby ensuring the contact area between the outer wall of the sealing ring 15 and the inner wall of the housing 9, and ensuring the sealing effect. The sealing ring 15 is a PU polyurethane rubber sealing ring. Since the sealing ring 15 will come into contact with insulating oil, and will cause wear with the inner wall of the housing 9 when moving, the PU polyurethane rubber sealing ring has good oil resistance and wear resistance. Compared with ordinary sealing rings, it plays a role in oil resistance and wear resistance. By adopting the design of limiting blocks 18 and connecting holes, the connection effect between the sealing ring 15 and the moving block 17 is enhanced, preventing the sealing ring 15 from falling off when the moving block 17 moves.

[0045] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An explosion-proof oil filling structure for an explosion-proof electrical cabinet, comprising an oil inlet valve (2) and an oil outlet valve (1), characterized in that, The oil inlet valve (2) is connected to the top wall of the explosion-proof electrical cabinet, and the oil outlet valve (1) is connected to the lower end of the explosion-proof electrical cabinet; The explosion-proof electrical cabinet is equipped with a base plate (3), and an air pump (4) is installed on the base plate (3). The air inlet of the air pump (4) is connected to a nitrogen storage device. A connecting pipe (8) is placed inside the oil inlet valve (2). The connecting pipe (8) is connected to the air filling pipe (11) and the oil filling pipe (10) through an adjustment mechanism. The air filling pipe (11) is connected to the air outlet of the air pump (4). The oil filling pipe (10) is connected to the pump body; A connecting block (6) is fixedly connected to the connecting pipe (8). A sealing gasket (7) is provided on the side of the connecting block (6) opposite to the oil inlet valve (2). The sealing gasket (7) is used to seal the oil inlet valve (2). A telescopic rod (5) is provided between the connecting block (6) and the base plate (3). The adjustment mechanism includes a connecting shell (9), a threaded hole (14), a sealing ring (15), a rotating shaft (16), and a moving block (17). The connecting shell (9) is connected to the oil filling pipe (10) and the air filling pipe (11) respectively. The connecting shell (9) is perpendicularly connected to the connecting pipe (8). The moving block (17) is disposed inside the connecting shell (9). The sealing ring (15) is fixedly connected to both ends of the moving block (17). Both sealing rings (15) abut against the inner wall of the connecting shell (9). The moving block (17) has a threaded hole (14). The rotating shaft (16) has an external thread. The external thread is threaded to the threaded hole (14). One end of the rotating shaft (16) extends out of the connecting shell (9). The connecting shell (9) and the rotating shaft (16) are rotatably connected by a sealed bearing. A gear (12) is fixedly connected to the rotating shaft (16), and a rack (13) is fixedly connected to the base plate (3). The rack (13) meshes with the gear (12). The moving block (17) moves within the connecting shell (9), causing the sealing ring (15) to block the oil filling pipe (10) or air filling pipe (11) at one end of the connecting shell (9), while the air filling pipe (11) or oil filling pipe (10) at the other end is connected to the connecting pipe (8). When the telescopic rod (5) retracts and the sealing gasket (7) abuts against the oil inlet valve (2), it drives the gear (12) to move and rotate on the rack (13); when the telescopic rod (5) extends, it drives the gear (12) to move and rotate on the rack (13), so that the connecting pipe (8) is connected to the oil filling pipe (10).

2. The explosion-proof oil-filling structure for an explosion-proof electrical cabinet according to claim 1, characterized by, The inner cavity of the connecting shell (9) and the moving block (17) are both rectangular structures.

3. The explosion-proof oil-filling structure for an explosion-proof electrical cabinet according to claim 1, characterized by, The inner ring wall of the sealing ring (15) has multiple connecting holes, and multiple limiting blocks (18) are fixedly connected to the moving block (17). The limiting blocks (18) can be inserted into the connecting holes.

4. The explosion-proof oil-filling structure for an explosion-proof electrical cabinet according to claim 3, characterized by The connection hole is a blind hole.

5. The explosion-proof oil-filling structure for an explosion-proof electrical cabinet according to claim 3, characterized by Both the connecting shell (9) and the inner wall of the oil filling pipe (10) are provided with a non-stick layer.

6. The explosion-proof oil-filling structure for an explosion-proof electrical cabinet according to claim 3, characterized by The sealing ring (15) is a PU polyurethane rubber sealing ring.

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