A sealing performance detection device of a transformer

Abstract

The application discloses a kind of sealing performance detection devices of transformer, it is related to transformer sealing detection field, including detection table and pneumatic detection component, the both ends of detection table are respectively provided with bottom surface detection mechanism and end surface detection mechanism, end surface detection mechanism includes end surface detection frame, and end surface sealing pad is equipped on end surface detection frame, bottom surface detection mechanism includes bottom surface detection frame, and bottom surface detection frame is used to be sleeved in the bottom of transformer, and side sealing pad is fixed in the inner wall of bottom surface detection frame, and pneumatic sensor is installed in bottom surface detection frame and end surface detection frame; Pneumatic detection component includes inflation equipment and negative pressure suction equipment, and first inflation pipeline is connected on end surface detection frame, second inflation pipeline and suction pipeline are connected on bottom surface mounting plate, first inflation pipeline and second inflation pipeline are connected inflation equipment, and suction pipeline is connected negative pressure suction equipment, and the way of air pressure is completed sealing detection, and the scrap rate caused by detection is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of transformer sealing performance testing, specifically to a transformer sealing performance testing device. Background Technology

[0002] As the core equipment for power transmission and conversion in a power system, the sealing performance of a transformer directly determines its operational reliability and service life. The inside of a transformer is filled with insulating oil and encapsulates precision electrical components such as the core and windings. If there are any gaps in the seal, external moisture, dust, and other impurities can easily penetrate the interior, causing deterioration of the insulating oil and a decrease in the insulation performance of the electrical components. This can lead to equipment failures or, in severe cases, safety accidents such as short circuits and leakage. Therefore, after the transformer is manufactured and assembled, it is essential to conduct rigorous sealing performance testing, making sealing testing one of the core procedures before the transformer leaves the factory.

[0003] The transformer casing is primarily manufactured using welding, and its overall sealing meets basic usage requirements. However, due to the demands of power transmission, mounting positions must be reserved on the top and sides of the casing to accommodate terminals, monitoring components, and other devices. The installation of these components can disrupt the original, intact sealing structure of the casing, creating a weak point in the sealing performance. Particularly noteworthy is that components on the transformer's sides are typically concentrated below the heat sink. This area, obstructed by the heat sink, has limited operating space, further increasing the difficulty of sealing testing.

[0004] Currently, the industry primarily uses the traditional water immersion test method to test the sealing performance of transformers. This method involves submerging the entire transformer under test in water and manually observing the formation of bubbles to determine the presence and location of sealing defects. However, this water immersion test method has significant technical drawbacks, becoming a key issue restricting the efficiency and cost control of transformer production testing: when poor sealing is detected, water can directly enter the transformer's interior through the sealing defect, coming into direct contact with the internal insulating oil and electrical components. This can easily cause the insulating oil to emulsify and fail, and metal components to corrode and oxidize. Even if the sealing defect is subsequently repaired, the internal insulation and electrical performance of the transformer has already been damaged, rendering it unusable. This results in a large number of transformers with minor sealing defects being scrapped, significantly increasing production costs. Furthermore, even transformers that pass the water immersion test require subsequent drying and cleaning, increasing testing procedures and time, and reducing overall testing efficiency.

[0005] In addition, traditional water immersion testing methods have the problem of low detection accuracy. For defects with small sealing gaps, the generated bubbles are small and rise slowly, which are easily overlooked by manual observation, leading to missed detection.

[0006] Therefore, developing a testing device that can accurately detect the sealing performance of transformers while preventing water from entering the transformer interior, and that can subsequently repair and reuse transformers with sealing defects, has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a transformer sealing performance testing device to address the deficiencies of the prior art.

[0008] The objective of this invention is achieved through the following technical solution: a transformer sealing performance testing device, comprising a testing platform, with a bottom surface testing mechanism and an end surface testing mechanism respectively provided at both ends of the testing platform. The end surface testing mechanism includes an end surface mounting plate and an end surface testing frame. One end of the end surface testing frame is connected to the end surface mounting plate, and the other end is connected to an end surface sealing gasket. The end surface sealing gasket is hollow and is used to press against the top surface of the transformer. The bottom surface testing mechanism includes a bottom surface mounting plate and a bottom surface testing frame. One end of the bottom surface testing frame is connected to the bottom surface mounting plate, and the other end is used to fit over the bottom of the transformer. A side sealing gasket is fixed to the inner wall of the bottom surface testing frame and presses against the bottom side of the transformer. A pressure sensor is installed inside both the bottom surface testing frame and the end surface testing frame.

[0009] It also includes a pneumatic detection component, which includes an inflation device and a negative pressure suction device. A first inflation pipe is connected to the end face detection frame, and a second inflation pipe and a suction pipe are connected to the bottom mounting plate. Both the first and second inflation pipes are connected to the inflation device, and the suction pipe is connected to the negative pressure suction device.

[0010] Furthermore, the bottom detection frame includes a large-size receiving frame and a small-size sealing frame. The small-size sealing frame is coaxially fixed to the large-size receiving frame. The large-size receiving frame has a receiving cavity through it along its own center line. The small-size sealing frame has a sealing cavity through it along its own center line. The side sealing gasket is installed on the inner wall of the sealing cavity.

[0011] Furthermore, the inner wall of the small-sized sealing frame is provided with two side sealing gaskets spaced apart along its own center line, and a sealing airbag is provided between the two side sealing gaskets. Each of the four edges of the small-sized sealing frame is provided with a sealing airbag, and the sealing airbag is interference-fitted between the two side sealing gaskets.

[0012] Furthermore, the bottom detection frame has a split structure, including a left half detection body and a right half detection body. The left half detection body and the right half detection body are symmetrical structures. Both the left half detection body and the right half detection body have linear movement freedom. The end face of the left half detection body near the right half detection body has a sealing layer fixed on both sides of the receiving cavity. The end face of the right half detection body near the left half detection body has a sealing groove. The sealing layer is interference-fitted into the sealing groove. The bottom mounting plate is provided with an inflation port and a negative pressure port. Both the inflation port and the negative pressure port extend into the receiving cavity. The inflation port is connected to a second inflation pipe, and the negative pressure port is connected to a suction pipe.

[0013] Furthermore, a lead screw groove is provided on the bottom mounting plate, and a bidirectional threaded lead screw is rotatably installed in the lead screw groove. Two lead screw sliders are threadedly fitted on the bidirectional threaded lead screw, and the threads of the two lead screw sliders are opposite. The two lead screw sliders are connected to the left half and the right half of the detection body respectively through a connecting rod. A motor is installed on the bottom mounting plate, and the output shaft of the motor is driven by the bidirectional threaded lead screw.

[0014] Furthermore, the end face detection mechanism also includes an end face lifting seat, a first end face cylinder, and a second end face cylinder. The first end face cylinder is arranged vertically, and its telescopic shaft is connected to the end face lifting seat. The second end face cylinder is horizontally mounted on the end face lifting seat, and its telescopic shaft is connected to the end face mounting plate. The bottom face detection mechanism also includes a lifting seat, a first cylinder, and a second cylinder. The first cylinder is arranged vertically, and its telescopic shaft is connected to the lifting seat. The second cylinder is horizontally mounted on the lifting seat, and its telescopic shaft is connected to the bottom face mounting plate.

[0015] Furthermore, the end face detection frame is connected to the end face mounting plate via an end face connecting rod. Hollow expansion tubes are fixed at the four corners of the end face detection frame. Multiple expansion slits are opened on the sidewall of the hollow expansion tube along its own circumference. The inner diameter of the hollow expansion tube gradually decreases in the direction away from the end face detection frame. A drive shaft is slidably arranged inside the hollow expansion tube. The drive shaft has the degree of freedom to move along the axial direction of the hollow expansion tube.

[0016] Furthermore, a drive plate is provided between the end face mounting plate and the end face detection frame. The drive plate is movably sleeved on the end face connecting rod. A third cylinder is provided on the end face mounting plate. The telescopic shaft of the third cylinder is connected to the drive plate. The hollow expansion tube is fixed on the drive plate.

[0017] Furthermore, the testing platform is provided with a positioning fixture mechanism, which includes a transverse positioning plate and a longitudinal positioning plate. Two transverse positioning plates are spaced apart along the length direction of the testing platform, and the transverse positioning plates have a degree of freedom to move along the length direction of the testing platform. Two longitudinal positioning plates are spaced apart along the width direction of the testing platform, and the longitudinal positioning plates have a degree of freedom to move along the width direction of the testing platform.

[0018] Furthermore, the top surface of the testing platform is provided with a transverse lead screw groove, in which a first bidirectional threaded lead screw is rotatably disposed. Two first lead screw sliders are threadedly fitted on the first bidirectional threaded lead screw, with the threads of the two first lead screw sliders having opposite directions. A transverse positioning plate is installed on the top surface of each of the two first lead screw sliders. The top surface of the testing platform is provided with a longitudinal lead screw groove, in which a second bidirectional threaded lead screw is rotatably disposed. Two second lead screw sliders are threadedly fitted on the second bidirectional threaded lead screw, with the threads of the two second lead screw sliders having opposite directions. A longitudinal positioning plate is installed on the top surface of each of the two second lead screw sliders. A first motor and a second motor are mounted on the testing platform. The output shaft of the first motor is driven and connected to the first bidirectional threaded lead screw, and the output shaft of the second motor is driven and connected to the second bidirectional threaded lead screw.

[0019] The beneficial effects of this invention are:

[0020] 1. The end-face detection frame is pressed against the top surface of the transformer, so that the area where components are located on the top of the transformer is inside the end-face detection frame. The bottom-face detection frame is fitted onto the transformer, so that the area where components are located on the side walls of the transformer is inside the bottom-face detection frame. This covers the component mounting positions of the transformer from both ends. The end-face detection frame is rapidly pressurized through the first air inlet pipe. Then, the pressure inside the end-face detection frame is monitored in real time by a pressure sensor. If the pressure continues to decrease, it indicates that the top surface of the transformer is not properly sealed. Next, the suction pipe creates a negative pressure inside the bottom-face detection frame. If the side sealing of the transformer is insufficient, the pressure inside the end-face detection frame will decrease more rapidly under the action of the negative pressure. If the pressure reading inside the end-face detection frame decreases... If the pressure rate remains constant, it indicates that the transformer's side sealing meets the requirements. When the pressure value within the end-face detection frame remains constant or decreases only slightly, it indicates that the transformer's top sealing meets the requirements. At this point, pressure is applied to the bottom-face detection frame, and the change in pressure readings is used to determine the transformer's side sealing condition. Thus, even when the transformer's top sealing is insufficient, the side sealing is tested using a "top-face pressurization, side-face negative pressure" method. This avoids the influence of air pressure interaction on the test results under simultaneous pressurization, ensuring accuracy. Furthermore, using air pressure for sealing testing fundamentally eliminates the problems of insulating oil emulsification and metal component corrosion caused by water intrusion into the transformer during traditional immersion testing. Even if minor sealing defects are detected, if the transformer's internal core components are undamaged, they can be repaired and put back into normal use, significantly reducing the scrap rate due to testing and substantially lowering manufacturing costs.

[0021] 2. The side sealing gasket is pressed tightly against the side wall of the transformer to achieve a seal, while the gaps caused by the chamfer of the transformer edges are sealed by a sealing airbag. This avoids the problem of gaps between the side sealing gasket and the side wall of the transformer caused by the chamfer, thus achieving a complete seal. This ensures that the air pressure in the bottom detection frame is only affected by the component mounting holes, improving the accuracy of the test results. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of a transformer sealing performance testing device according to the present invention. Figure 1 ;

[0023] Figure 2 This is a schematic diagram of the end face detection frame in a transformer sealing performance testing device of the present invention;

[0024] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0025] Figure 4 This is a schematic diagram of the bottom detection frame in a transformer sealing performance testing device of the present invention;

[0026] Figure 5 This is a schematic diagram of the structure of a transformer sealing performance testing device according to the present invention. Figure 2 ;

[0027] Figure 6 This is a schematic diagram of the structure of a transformer sealing performance testing device according to the present invention. Figure 3 ;

[0028] Figure 7 This is a schematic diagram of the transverse positioning plate in a transformer sealing performance testing device of the present invention;

[0029] Figure 8 This is a bottom view of the bottom detection frame in a transformer sealing performance testing device according to the present invention;

[0030] Figure 9 This is a schematic diagram of the internal structure of the left half of the detection body in a transformer sealing performance testing device of the present invention;

[0031] In the diagram, 1-Detection platform, 2-End face mounting plate, 3-End face detection frame, 4-End face sealing gasket, 5-Bottom face mounting plate, 6-Bottom face detection frame, 7-Side sealing gasket, 8-Pressure sensor, 9-First inflation pipe, 10-Suction pipe, 11-Second inflation pipe, 12-Large size receiving frame, 13-Small size sealing frame, 14-Receiving cavity, 15-Sealing airbag, 16-Left half detection body, 17-Right half detection body, 18-Sealing layer, 19-Sealing groove, 20-Screw groove, 21-Double threaded screw, 22-Screw slider, 23-Connecting rod, 24-Motor, 25-Sealing cavity, 26-Inflation port, 27-Negative pressure port, 29-End face lifting seat, 30-First end face cylinder, 31-Second end face cylinder 32-Lifting seat, 33-First cylinder, 34-Second cylinder, 35-Transverse positioning base plate, 36-Transverse sliding plate, 37-End face connecting rod, 38-Hollow expansion tube, 39-Expansion joint, 40-Drive shaft, 41-Drive plate, 42-Third cylinder, 43-Transverse positioning plate, 44-Longitudinal positioning plate, 45-Transverse lead screw groove, 46-First bidirectional threaded lead screw, 47-Longitudinal lead screw groove, 48-Second bidirectional threaded lead screw, 49-First motor, 50-Second motor, 51-Mounting groove, 52-Electromagnet, 53-Spring, 54-Permanent magnet, 55-Bottom sealing groove, 56-Sealing sliding component, 57-Bottom sealing gasket, 58-Sealing spring, 59-Locking screw, 60-Cam. Detailed Implementation

[0032] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0033] Example 1

[0034] like Figures 1 to 9As shown, a transformer sealing performance testing device includes a testing platform 1. A bottom surface testing mechanism and an end surface testing mechanism are respectively provided at both ends of the testing platform 1. The end surface testing mechanism includes an end surface mounting plate 2 and an end surface testing frame 3. One end of the end surface testing frame 3 is connected to the end surface mounting plate 2, and the other end is connected to an end surface sealing gasket 4. The end surface sealing gasket 4 is hollow and is used to press against the top surface of the transformer. The bottom surface testing mechanism includes a bottom surface mounting plate 5 and a bottom surface testing frame 6. One end of the bottom surface testing frame 6 is connected to the bottom surface mounting plate 5, and the other end is used to fit over the bottom of the transformer. A side sealing gasket 7 is fixed to the inner wall of the bottom surface testing frame 6 and presses against the bottom side of the transformer. Air pressure sensors are installed inside both the bottom surface testing frame 6 and the end surface testing frame 3. The sensor 8 also includes a pneumatic detection assembly, which includes an inflation device and a negative pressure suction device. A first inflation pipe 9 is connected to the end face detection frame 3, and a second inflation pipe 11 and a suction pipe 10 are connected to the bottom mounting plate 5. Both the first inflation pipe 9 and the second inflation pipe 11 are connected to the inflation device, and the suction pipe 10 is connected to the negative pressure suction device. A robotic arm places the transformer to be tested onto the detection platform 1, tilting the transformer so that its top surface corresponds to the end face detection frame 3 and its bottom surface corresponds to the bottom face detection frame 6. Then, the end face detection frame 3 moves closer to the transformer, causing the end face sealing gasket 4 to press firmly against the top surface of the transformer. The size of the end face sealing gasket 4 matches the size of the transformer, ensuring that the components arranged on the top surface of the transformer are positioned within the end face sealing gasket 4. The inner ring positions the components on the top surface of the transformer within the end-face detection frame 3. Then, the bottom detection frame 6 is fitted over the bottom of the transformer, placing the area on the transformer's sidewalls where components are located within the bottom detection frame 6. This covers the component mounting positions from both ends of the transformer. After the end-face detection frame 3 and bottom detection frame 6 are properly aligned, a detection operation is performed. First, the sealing of the transformer's top surface is checked. Specifically, the end-face detection frame 3 is rapidly pressurized through the first inflation pipe 9. Once the pressure reaches the set value, the first inflation pipe 9 is closed. Then, the pressure inside the end-face detection frame 3 is monitored in real time by the pressure sensor 8. If the sealing of the component mounting holes on the top surface of the transformer is insufficient, and the transformer's internal pressure is normal, gas from the end-face detection frame 3 will continuously flow into the transformer. The airflow causes the air pressure inside the end-face detection frame 3 to gradually decrease. This continuous pressure decrease reflects insufficient sealing of the transformer's top surface. If the air pressure inside the end-face detection frame 3 remains constant or the rate of decrease is not significant, it indicates that the sealing of the component mounting holes on the transformer's top surface meets the usage requirements. The operating state of the bottom-face detection frame 6 is selected based on the sealing condition of the transformer's top surface. When the transformer's top surface sealing is insufficient, a negative pressure is generated inside the bottom-face detection frame 6 through the suction pipe 10. If the transformer's side sealing is insufficient, the negative pressure will cause gas inside the transformer to enter the bottom-face detection frame 6. The decrease in internal air pressure will then cause the pressure inside the end-face detection frame 3 to decrease more rapidly. If the rate of decrease in pressure reading inside the end-face detection frame 3 remains constant...This indicates that the transformer's side sealing meets the requirements. Therefore, when the transformer's top sealing is insufficient, the side sealing is tested using a "top surface pressurization, side surface negative pressure" method. On one hand, this avoids the situation where simultaneous pressurization in the end-face detection frame 3 and the bottom-face detection frame 6 would cause air to enter the transformer from both the top and sides simultaneously, resulting in a less significant pressure drop within the two frames and thus affecting the test results. On the other hand, the simultaneous application of pressurization and negative pressure amplifies the pressure drop rate within the end-face detection frame 3, making the test results more obvious, ensuring accuracy, and eliminating the need for prolonged monitoring of the pressure drop rate, thus improving testing efficiency. When the transformer top surface... When the sealing of the component mounting holes on the transformer side meets the requirements, pressure is applied to the bottom detection frame 6 through the second air filling pipe 11. The pressure sensor 8 inside the bottom detection frame 6 monitors the pressure. If the pressure continues to decrease, it indicates that the sealing of the component mounting holes on the transformer side does not meet the requirements. If the pressure remains constant, or if the decrease is within the allowable range within the set monitoring time, it indicates that the sealing of the component mounting holes on the transformer side meets the usage requirements. This completes the transformer's sealing performance test. Using air pressure to complete the sealing test fundamentally eliminates the problems of insulating oil emulsification and metal component corrosion caused by water intrusion into the transformer during traditional water immersion testing. Even if minor sealing defects are detected, the core components inside the transformer are not damaged and can be repaired for normal use, significantly reducing the scrap rate caused by testing and significantly lowering production and manufacturing costs. In practice, the inflation equipment can be an air compressor (Atlas Copco GA 37VSD+) or a pneumatic booster pump (Haskel DSTV-70); the negative pressure suction equipment can be a rotary vane vacuum pump (Leybold D16C) or a vacuum jet pump (Spira Sarco 200).

[0035] Example 2

[0036] Based on Example 1, such as Figures 1 to 6As shown, a positioning fixture mechanism is provided on the testing table 1. The positioning fixture mechanism includes a transverse positioning plate 43 and a longitudinal positioning plate 44. Two transverse positioning plates 43 are spaced apart along the length of the testing table 1, and the transverse positioning plates 43 have a degree of freedom to move along the length of the testing table 1. Two longitudinal positioning plates 44 are spaced apart along the width of the testing table 1, and the longitudinal positioning plates 44 have a degree of freedom to move along the width of the testing table 1. A transverse screw groove 45 is opened on the top surface of the testing table 1, and a first bidirectional threaded screw 46 is rotatably installed in the transverse screw groove 45. The first bidirectional threaded screw 46 has two first screw sliders threadedly mounted on it. The threads of the two first screw sliders have opposite directions. A transverse positioning plate 43 is installed on the top surface of each of the two first screw sliders. A longitudinal screw groove 47 is opened on the top surface of the testing table 1. A second bidirectional threaded screw 48 is rotatably mounted in the longitudinal screw groove 47. Two second screw sliders are threadedly mounted on the second bidirectional threaded screw 48. The threads of the two second screw sliders have opposite directions. A longitudinal positioning plate 44 is installed on the top surface of each of the two second screw sliders. A first motor 49 and a second... Motor 50, the output shaft of the first motor 49 is driven by a first bidirectional threaded screw 46, and the output shaft of the second motor 50 is driven by a second bidirectional threaded screw 48. Before the transformer sealing performance test, the transformer is first positioned by a positioning fixture mechanism. The first motor 49 drives the first bidirectional threaded screw 46 to rotate. Since the threads of the two first screw sliders are turned in opposite directions, the two transverse positioning plates 43 move in opposite directions. The first screw sliders drive the transverse positioning plates 43 to move closer to the transformer. The transverse positioning of the transformer is completed by the two transverse positioning plates 43. Simultaneously, the second motor 50 drives the second bidirectional threaded screw 48 to rotate. Since the threads of the two second screw sliders rotate in opposite directions, the two longitudinal positioning plates 44 move in opposite directions. The second screw sliders drive the longitudinal positioning plates 44 closer to the transformer, completing the longitudinal positioning of the transformer. This places the transformer centering fixture on the testing table 1, ensuring that the top surface of the transformer accurately aligns with the end face testing frame 3 and the bottom surface testing frame 6. This allows the end face testing frame 3 to precisely abut against the top surface of the transformer, and the bottom surface testing frame 6 to precisely fit onto the bottom of the transformer. In practice, both the transverse positioning plate 43 and the longitudinal positioning plate 44 are smoothed to reduce friction between the transverse positioning plate 43 and the transformer, and to reduce friction between the longitudinal positioning plate 44 and the transformer. This ensures that after the two transverse positioning plates 43 contact the transformer, the longitudinal positioning plate 44 can still push the transformer to move, allowing the transverse and longitudinal positioning of the transformer to occur simultaneously.

[0037] Example 3

[0038] Because the components on the side of the transformer are installed close to the heat sink, the horizontal positioning plate 43 is located within the coverage area of ​​the bottom detection frame 6. This causes the horizontal positioning plate 43 to obstruct the bottom detection frame 6 from being fitted onto the transformer. Therefore, after the transformer is positioned, the horizontal positioning plate 43 needs to be removed to avoid obstructing the bottom detection frame 6. However, after the transformer loses the positioning of the horizontal positioning plate 43, when the end face detection frame 3 engages with the transformer, it will push the transformer to move, making it difficult for the end face sealing gasket 4 to adhere tightly to the top surface of the transformer and form a good seal. Therefore, based on embodiment two, as... Figures 1 to 4 As shown, the end face detection frame 3 is connected to the end face mounting plate 2 via the end face connecting rod 37. Hollow expansion tubes 38 are fixed at each of the four corners of the end face detection frame 3. Multiple expansion slots 39 are formed on the sidewalls of the hollow expansion tubes 38 along their circumference. The inner diameter of the hollow expansion tubes 38 gradually decreases away from the end face detection frame 3. A drive shaft 40 is slidably installed inside the hollow expansion tube 38, and the drive shaft 40 has the freedom to move axially along the hollow expansion tube 38. A drive plate 41 is provided between the end face mounting plate 2 and the end face detection frame 3. The drive plate 41 is movably sleeved on the end face connecting rod 37. A third cylinder 42 is provided on the end face mounting plate 2, and the telescopic shaft of the third cylinder 42 is connected to the drive plate 41. The hollow expansion tubes 38 are fixed on the drive plate 41. Since mounting holes are formed at the edges of the four sides of the transformer top surface, the transformer is fixed using these mounting holes. Specifically, the transformer... After the transformer centering fixture is completed, the end face inspection frame 3 moves closer to the transformer, so that the end face inspection frame 3, carrying the end face sealing gasket 4, presses against the top surface of the transformer. At this time, the hollow expansion tube 38 is inserted into the mounting hole on the top surface of the transformer. Then, the third cylinder 42 drives the drive plate 41 to move closer to the end face inspection frame 3. The drive plate 41 drives the drive shaft 40 to be inserted into the inner hole of the hollow expansion tube 38. As the inner diameter of the hollow expansion tube 38 gradually decreases, the drive shaft 40 will squeeze the hollow expansion tube 38 to produce deformation. Under the action of the expansion joint 39, the hollow expansion tube 38 can smoothly deform outward, so that the hollow expansion tube 38 presses against the inner wall of the mounting hole, thereby connecting the transformer to the end face inspection frame 3. The end face sealing gasket 4 is compressed and pressed against the top surface of the transformer to maintain a high sealing strength. Then, the transverse positioning plate 43 is moved away, and finally the bottom inspection frame 6 is put on the bottom of the transformer.

[0039] Example 4

[0040] Because the bottom surface inspection frame 6 needs to be fitted onto the bottom of the transformer for sealing performance testing, the horizontal positioning plate 43 will block the bottom surface inspection frame 6 no matter how it is moved. Therefore, based on embodiment three, as follows: Figures 1 to 7As shown, the transverse positioning plate 43 includes a transverse positioning base plate 35 and a transverse sliding plate 36. The bottom of the transverse positioning base plate 35 is fixed on the first lead screw slider. A mounting groove 51 is formed on the top surface of the transverse positioning base plate 35. One end of the transverse sliding plate 36 is slidably fitted into the mounting groove 51. An electromagnet 52 and a spring 53 are installed in the mounting groove 51. The two ends of the spring 53 are respectively connected to the transverse sliding plate 36 and the transverse positioning base plate 35. A permanent magnet 54 is provided at the bottom of the transverse sliding plate 36. When the electromagnet 52 is energized, it generates magnetic poles with the same magnetism as the permanent magnet 54. When positioning the transformer... When the electromagnet 52 is energized, it repels the permanent magnet 54, causing the permanent magnet 54 to move the transverse sliding plate 36 upward. The spring 53 is in a stretched state, and the top of the transverse sliding plate 36 extends out from the transverse lead screw groove. The movement of the transverse sliding plate 36 can push the transformer to move, thereby completing the positioning fixture of the transformer. After the hollow expansion tube 38 is connected to the transformer, the electromagnet 52 is de-energized, and the transverse sliding plate 36 moves downward and resets under the action of the spring 53, so that the transverse sliding plate 36 is located below the top surface of the detection table 1, ensuring that the transverse positioning plate 43 will not affect the assembly of the bottom detection frame 6 and the transformer.

[0041] Example 5

[0042] Based on Example 4, such as Figures 1 to 6 As shown, the bottom detection frame 6 includes a large-size receiving frame 12 and a small-size sealing frame 13. The small-size sealing frame 13 is coaxially fixed to the large-size receiving frame 12. The large-size receiving frame 12 has a receiving cavity 14 extending through its own center line. The small-size sealing frame 13 has a sealing cavity 25 extending through its own center line. The side sealing gasket 7 is installed on the inner wall of the sealing cavity 25. Since components need to be installed on the side of the transformer, the thickness of the side sealing gasket 7 needs to be greater than the length of the components so that the bottom detection frame 6 can accommodate the components while compressing the side sealing gasket 7. The side sealing gasket 7 is pressed tightly against the side wall of the transformer. However, the side sealing gasket 7 is made of elastic material, usually fluororubber. The greater the thickness, the greater its compressible deformation, which can easily cause leakage under high or negative pressure. Therefore, the inner cavity of the bottom detection frame 6 is composed of a stepped structure consisting of a receiving cavity 14 and a sealing cavity 25. The components are located in the larger receiving cavity 14, and the side sealing gasket 7 is installed on the inner wall of the smaller sealing cavity 25. This reduces the thickness of the side sealing gasket 7, allowing it to press tightly against the side wall of the transformer and achieve a better seal.

[0043] Example 6

[0044] Since the bottom detection frame 6 needs to fit over the bottom of the transformer and accommodate the components on the transformer's sidewall, it needs to avoid these components. However, the bottom detection frame 6 includes a small-sized sealing frame 13, which prevents the small-sized sealing frame 13 from passing through the components on the transformer's sidewall. Therefore, based on embodiment five, as follows... Figures 1 to 6 As shown, the bottom detection frame 6 has a split structure, including a left half detection body 16 and a right half detection body 17. The left half detection body 16 and the right half detection body 17 are symmetrical. Both the left half detection body 16 and the right half detection body 17 have linear movement freedom. The end face of the left half detection body 16 near the right half detection body 17 is fixed with a sealing layer 18 on both sides of the receiving cavity 14. The end face of the right half detection body 17 near the left half detection body 16 is provided with a sealing groove 19. The sealing layer 18 is interference-fitted into the sealing groove 19. The bottom mounting plate 5 is provided with an inflation port 26 and a negative pressure port 27. Both the negative pressure port 27 and the inflation port 26 extend into the receiving cavity 14. The inflation port 26 is connected to the second inflation pipe 11, and the negative pressure port 27 is connected to the suction pipe 10. A screw groove 20 is provided on the bottom mounting plate 5, and a bidirectional threaded screw 21 is rotatably installed in the screw groove 20. Two screw sliders 22 are threaded on the bidirectional threaded screw 21, and the threads of the two screw sliders 22 are opposite. The two screw sliders 22 are connected to the left half of the detection body 16 and the right half of the detection body 17 respectively through the connecting rod 23. A motor 24 is installed on the bottom mounting plate 5, and the output shaft of the motor 24 is connected to the bidirectional threaded screw 21 to drive the bottom detection frame. The bottom detection frame 6 is designed as a split structure, which avoids components on the side of the transformer when assembling the frame. Specifically, the left half of the detection body 16 and the right half of the detection body 17 are normally separate. After the transformer is positioned, the end face mounting plate 2 moves the left half of the detection body 16 and the right half of the detection body 17 closer to the transformer, so that the left half of the detection body 16 and the right half of the detection body 17 are located on both sides of the transformer. Then, the motor 24 drives the bidirectional threaded screw 21 to rotate. Since the threads of the two screw sliders 22 are opposite, the two connecting rods 23 move in opposite directions, so that the left half of the detection body 16 and the right half of the detection body 17 are located on both sides of the transformer. The half-shaped detection body 17 contacts to form the bottom detection frame 6. Similarly, the side sealing gasket 7 is also a half-shaped structure. The two half-shaped sealing gaskets are pressed together to form the side sealing gasket 7, which can compress the side sealing gasket 7 to fit tightly against the side wall of the transformer. After the left half-shaped detection body 16 contacts the right half-shaped detection body 17, the sealing layer 18 is inserted into the sealing groove 19, and the length of the sealing layer 18 is greater than the depth of the sealing groove 19, so that the sealing layer 18 undergoes compression deformation and is interference-fitted into the sealing groove 19. This gives the contact surface between the left half-shaped detection body 16 and the right half-shaped detection body 17 a high sealing performance, without affecting the sealing performance test of the transformer. In specific implementation, the two connecting rods 23 are respectively connected to the left half-shaped detection body 16 and the right half-shaped detection body 17 through the first screw, which can replace the bottom detection frame 6 of the corresponding size according to the size of the transformer. Secondly, the end face connecting rod 37 is connected to the end face detection frame 3 through the flange, which can replace the end face detection frame 3 of the corresponding size according to the size of the transformer, and can adapt to the sealing performance test of transformers of various sizes.

[0045] Example 7

[0046] The split-structure bottom surface detection frame 6 creates a gap between it and the bottom mounting plate 5, affecting the accuracy of transformer seal testing. If the bottom sealing gasket is directly fixed to the bottom of both the left and right halves of the detection body 16, causing it to be in a compressed state in contact with the bottom mounting plate 5, it will result in significant friction between them. This requires greater driving force and accelerates the wear of the bottom sealing gasket. Therefore, based on embodiment six, as... Figures 1 to 9 As shown, bottom sealing grooves 55 are provided on the end face of the left half-type detector 16 near the bottom mounting plate 5 and the end face of the right half-type detector 17 near the bottom mounting plate 5. Taking the left half-type detector 16 as an example, the bottom sealing groove 55 is U-shaped, and the two ends of the bottom sealing groove 55 pass through the two ends of the opening of the left half-type detector 16, respectively. A sealing sliding member 56 is slidably arranged in the bottom sealing groove 55. The end of the sealing sliding member 56 near the bottom mounting plate 5 is connected to a bottom sealing gasket 57 by a screw. A sealing spring is provided in the bottom sealing groove 55. 58. The two ends of the sealing spring 58 are respectively connected to the sealing sliding member 56 and the left half of the detection body 16. The side wall of the left half of the detection body 16 is threaded with a locking screw 59. A cam 60 is fixedly sleeved on the locking screw 59. The cam 60 is located in the bottom sealing groove 55 and contacts the end of the sealing sliding member 56 away from the bottom sealing gasket 57. After the left half of the detection body 16 and the right half of the detection body 17 contact to form the bottom detection frame 6, the locking screw 59 on the left half of the detection body 16 and the right half of the detection body 17 is tightened, so that the locking screw 59 drives the cam. The cam 60 deflects downwards, pressing the sealing slider 56 to move. This causes the sealing slider 56 to press the bottom sealing gasket 57 against the bottom mounting plate 5. Because the bottom sealing gasket 57 is compressed, the bottom sealing gasket 57 inside the left half of the detection body 16 can press against the bottom sealing gasket 57 inside the right half of the detection body 17, forming a closed sealing gasket. This sealing gasket is compressed and pressed against the bottom mounting plate 5. Thus, after the left half of the detection body 16 contacts the right half of the detection body 17, the sealing gasket presses against the bottom mounting plate. 5. This prevents the sealing gasket from being worn, greatly improving its service life. The threaded connection of the locking screw 59 maintains the compression state of the sealing gasket, ensuring a high sealing strength between the bottom detection frame 6 and the bottom mounting plate 5. After the test is completed, loosening the locking screw 59 causes the cam 60 to reset, and the sealing sliding member 56 resets under the reaction force of the sealing spring 58, separating the bottom sealing gasket 57 from the bottom mounting plate 5. This ensures that the bottom sealing gasket 57 will not be worn when the left half of the detection body 16 separates from the right half of the detection body 17.

[0047] Example 8

[0048] Since most transformers have chamfered edges, resulting in rounded edges, gaps can form between the side sealing gasket 7 and the edges, affecting the accuracy of transformer sealing performance testing. Therefore, based on Example 7, as follows... Figures 1 to 4 As shown, the inner wall of the small-sized sealing frame 13 is provided with two side sealing gaskets 7 spaced apart along its center line. A sealing airbag 15 is provided between the two side sealing gaskets 7. Each of the four edges of the small-sized sealing frame 13 is provided with a sealing airbag 15. The sealing airbag 15 is interference-fitted between the two side sealing gaskets 7. The inflation valve tube of the sealing airbag 15 passes through the outer wall of the small-sized sealing frame 13. The inflation valve tube is connected to an inflation device, such as an air pump, through a hose, which can automatically inflate the sealing airbag 15. The side sealing gaskets 7 are pressed tightly against the side wall of the transformer to achieve a seal. The gaps caused by the chamfer of the transformer edges are sealed by the sealing airbag 15, thereby avoiding the problem of gaps between the side sealing gaskets 7 and the side wall of the transformer caused by the chamfer. This achieves a complete seal and ensures that the air pressure in the bottom detection frame 6 is only affected by the component mounting hole position, thus improving the accuracy of the detection results.

[0049] Example 9

[0050] Based on Example 8, such as Figures 1 to 6 As shown, the end face inspection mechanism also includes an end face lifting seat 29, a first end face cylinder 30, and a second end face cylinder 31. The first end face cylinder 30 is vertically arranged, and its telescopic shaft is connected to the end face lifting seat 29. The second end face cylinder 31 is horizontally mounted on the end face lifting seat 29, and its telescopic shaft is connected to the end face mounting plate 2. The bottom face inspection mechanism also includes a lifting seat 32, a first cylinder 33, and a second cylinder 34. The first cylinder 33 is vertically arranged, and its telescopic shaft is connected to the lifting seat 32. The second cylinder 34 is horizontally mounted on the lifting seat 32, and its telescopic shaft is connected to the bottom face mounting plate 5. Since the transformer will undergo centering treatment first, the horizontal mounting positions of the end face inspection frame 3 and the bottom face inspection frame 6 are... Since the transformer is positioned at the center, transformers of different sizes only require adjustment of the height of the end face detection frame 3 and the bottom face detection frame 6. The height of the end face detection frame 3 can be adjusted by the first end face cylinder 30 so that the end face detection frame 3 corresponds to the top surface of the transformer. Then, the end face detection frame 3 is moved closer to the transformer by the second end face cylinder 31 so that the end face sealing gasket 4 is pressed tightly against the top surface of the transformer. The height of the bottom face detection frame 6 can be adjusted by the first cylinder 33 so that the bottom face detection frame 6 corresponds to the bottom surface of the transformer. Then, the bottom face detection frame 6 is moved by the second cylinder 34 so that the left half detection body 16 and the right half detection body 17 are moved to the two sides of the transformer. Finally, the left half detection body 16 and the right half detection body 17 contact each other to form the bottom face detection frame 6.

Claims

1. A transformer sealing performance testing device, comprising a testing platform, characterized in that, The testing platform has a bottom surface testing mechanism and an end surface testing mechanism at both ends. The end surface testing mechanism includes an end surface mounting plate and an end surface testing frame. One end of the end surface testing frame is connected to the end surface mounting plate, and the other end is connected to an end surface sealing gasket. The end surface sealing gasket is hollow and is used to press against the top surface of the transformer. The bottom surface testing mechanism includes a bottom surface mounting plate and a bottom surface testing frame. One end of the bottom surface testing frame is connected to the bottom surface mounting plate, and the other end is used to fit over the bottom of the transformer. A side sealing gasket is fixed to the inner wall of the bottom surface testing frame and is pressed against the bottom side of the transformer. A pressure sensor is installed inside both the bottom surface testing frame and the end surface testing frame. It also includes a pneumatic detection component, which includes an inflation device and a negative pressure suction device. A first inflation pipe is connected to the end face detection frame, and a second inflation pipe and a suction pipe are connected to the bottom mounting plate. Both the first inflation pipe and the second inflation pipe are connected to the inflation device, and the suction pipe is connected to the negative pressure suction device. The end face detection frame is rapidly pressurized through the first air inlet pipe. The working state of the bottom face detection frame is selected according to the sealing condition of the transformer top surface. When the sealing of the transformer top surface is insufficient, negative pressure is generated in the bottom face detection frame through the air intake pipe. The bottom detection frame includes a large-size receiving frame and a small-size sealing frame. The small-size sealing frame is coaxially fixed to the large-size receiving frame. The large-size receiving frame has a receiving cavity through its own center line. The small-size sealing frame has a sealing cavity through its own center line. The side sealing gasket is installed on the inner wall of the sealing cavity. The bottom detection frame has a split structure, including a left half detection body and a right half detection body. The left half detection body and the right half detection body are symmetrical structures. Both the left half detection body and the right half detection body have linear movement freedom. The end face of the left half detection body near the right half detection body has a sealing layer fixed on both sides of the receiving cavity. The end face of the right half detection body near the left half detection body has a sealing groove. The sealing layer is interference-fitted into the sealing groove. The bottom mounting plate is provided with an inflation port and a negative pressure port. Both the inflation port and the negative pressure port extend into the receiving cavity. The inflation port is connected to a second inflation pipe, and the negative pressure port is connected to a suction pipe.

2. The transformer sealing performance testing device according to claim 1, characterized in that, The inner wall of the small-sized sealing frame is provided with two side sealing gaskets spaced apart along its own center line, and a sealing airbag is provided between the two side sealing gaskets. Each of the four edges of the small-sized sealing frame is provided with a sealing airbag, and the sealing airbag is interference-fitted between the two side sealing gaskets.

3. The transformer sealing performance testing device according to claim 1, characterized in that, The bottom mounting plate has a lead screw groove, in which a bidirectional threaded lead screw is rotatably installed. Two lead screw sliders are threaded onto the bidirectional threaded lead screw, and the threads of the two lead screw sliders are opposite. The two lead screw sliders are connected to the left half and the right half of the detection body respectively through a connecting rod. A motor is installed on the bottom mounting plate, and the output shaft of the motor is driven by the bidirectional threaded lead screw.

4. The transformer sealing performance testing device according to claim 1, characterized in that, The end face detection mechanism further includes an end face lifting seat, a first end face cylinder, and a second end face cylinder. The first end face cylinder is arranged vertically, and its telescopic shaft is connected to the end face lifting seat. The second end face cylinder is horizontally mounted on the end face lifting seat, and its telescopic shaft is connected to the end face mounting plate. The bottom face detection mechanism further includes a lifting seat, a first cylinder, and a second cylinder. The first cylinder is arranged vertically, and its telescopic shaft is connected to the lifting seat. The second cylinder is horizontally mounted on the lifting seat, and its telescopic shaft is connected to the bottom face mounting plate.

5. The transformer sealing performance testing device according to claim 4, characterized in that, The end face detection frame is connected to the end face mounting plate via an end face connecting rod. Hollow expansion tubes are fixed at the four corners of the end face detection frame. Multiple expansion slits are opened on the side wall of the hollow expansion tube along its own circumference. The inner diameter of the hollow expansion tube gradually decreases in the direction away from the end face detection frame. A drive shaft is slidably installed inside the hollow expansion tube. The drive shaft has the freedom to move along the axial direction of the hollow expansion tube.

6. The transformer sealing performance testing device according to claim 5, characterized in that, A drive plate is provided between the end face mounting plate and the end face detection frame. The drive plate is movably sleeved on the end face connecting rod. A third cylinder is provided on the end face mounting plate. The telescopic shaft of the third cylinder is connected to the drive plate. The hollow expansion tube is fixed on the drive plate.

7. The transformer sealing performance testing device according to claim 1, characterized in that, The testing platform is equipped with a positioning fixture mechanism, which includes a transverse positioning plate and a longitudinal positioning plate. Two transverse positioning plates are spaced apart along the length of the testing platform, and the transverse positioning plates have a degree of freedom to move along the length of the testing platform. Two longitudinal positioning plates are spaced apart along the width of the testing platform, and the longitudinal positioning plates have a degree of freedom to move along the width of the testing platform.

8. The transformer sealing performance testing device according to claim 7, characterized in that, The top surface of the testing platform has a transverse screw groove, in which a first bidirectional threaded screw is rotatably mounted. Two first screw sliders are threaded onto the first bidirectional threaded screw, with opposite thread directions. A transverse positioning plate is mounted on the top surface of each of the two first screw sliders. The top surface of the testing platform also has a longitudinal screw groove, in which a second bidirectional threaded screw is rotatably mounted. Two second screw sliders are threaded onto the second bidirectional threaded screw, with opposite thread directions. A longitudinal positioning plate is mounted on the top surface of each of the two second screw sliders. A first motor and a second motor are mounted on the testing platform. The output shaft of the first motor is connected to the first bidirectional threaded screw, and the output shaft of the second motor is connected to the second bidirectional threaded screw.

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