GB2622498A - Leak detection apparatus and method for weld of corrugated diaphragm of pressure sensor - Google Patents

Abstract

A leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor is provided that includes a detection shell 4 which includes a detection cover 41 and a detection base 42. A diaphragm inner cavity 11 is formed between a metal corrugated diaphragm 400 on the pressure sensor and the detection cover, and a diaphragm outer cavity 12 is formed between the metal corrugated diaphragm and an inner wall of a pressure ring 300 on the pressure sensor. A leak detection cavity 13 is formed between an outer wall of the pressure ring and an inner wall of the lower detection base as well as a portion of a sensor housing 500. A micro vacuum pump (9, figure 5) and a helium storage tank (10) communicate with a gas inlet hole 411; and a helium mass spectrometer leak detector (8) communicates with a leak detection hole 412. Also, a leak detection method for a weld of a corrugated diaphragm of a pressure sensor is described (figure 4).

Description

LEAK DETECTION APPARATUS AND METHOD FOR WELD OF CORRUGATED DIAPHRAGM OF PRESSURE SENSOR

[0001] This application claims priority of Chinese Patent Application No. 202211651946.5 filed with the China National Intellectual Property Administration on December 22, 2022 and entitled "LEAK DE 1ECTION APPARATUS AND METHOD FOR WELD OF CORRUGATED DIAPHRAGM OF PRESSURE SENSOR", which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

[0002] Embodiments of this application are related to the field of detection apparatus, and in particular, to a leak detection apparatus and method for a weld of a corrugated diaphragm of a pressure sensor.

BACKGROUND OF THE INVENTION

[0003] A pressure sensor is one of the most widely used sensors in industrial fields. To isolate a pressure sensitive chip from a tested medium, typical pressure sensors all use metal corrugated diaphragms for isolation. Referring to FIG 1, which is a sectional view of a pressure sensor that includes a pressure sensitive chip 100, an oil filler port 200, a pressure ring 300, a metal corrugated diaphragm 400, and a sensor housing 500. The metal corrugated diaphragm 400 is isolated from the pressure sensitive chip 100 by filling silicone oil through the oil filler port 200. The metal corrugated diaphragm 400 not only serves as a medium for isolation, but also transmits pressure to the pressure sensitive chip 100 without loss.

[0004] A thickness of the metal corrugated diaphragm 400 is generally between 3 him and 30 Rm. In practical production, the metal corrugated diaphragm 400 is usually clamped between the pressure ring 300 and the sensor housing 500. The pressure ring 300, the metal corrugated diaphragm 400, and the sensor housing 500 are welded together via laser, electron beams, or plasma, or in other manners A welding of the metal corrugated diaphragm 400 is an important process during production of a pressure sensor, and a quality of welding determines performance of the whole sensor. In production, slight leaks frequently occur in a weld due to poor diaphragm welding, and oil leak occurs after silicone oil is filled. This may cause the entire sensor to be rejected, which reduces a qualification ratio of products.

[0005] Currently, most detection methods for detecting a leak for a weld of the metal corrugated diaphragm 400 of the pressure sensor are performed in the following manner: silicone oil is first filled, and then leakage of silicone oil is manually detected via a high-power microscope. However, methods as such have poor detection accuracy, low detection efficiency, and missing or erroneous detections of oil leakage may often occur. Meanwhile, a fact that an un-qualified product is detected only after silicone oil is filled also results in waste of working hours and materials.

SUMMARY OF THE INVENTION

[0006] To resolve the foregoing problems of poor accuracy, low detection efficiency, and wastes of working hours and materials in manual leak detection, a leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor is provided in a first aspect of this application, including a detection seat. The detection seat includes a detection cover and a lower detection base that are engaged with each other, and an inner activity of the detection seat is enclosed by the detection cover and the lower detection base.

[0007] The inner cavity of the detection seat is configured to place a pressure sensor to-be-detected. The pressure sensor is fixed on an inner bottom wall of the lower detection base via a sensor holder. A diaphragm inner cavity is formed between the metal corrugated diaphragm of the pressure sensor and the detection cover, and a diaphragm outer cavity is formed between the metal corrugated diaphragm and an inner wall of the pressure ring. A leak detection cavity is formed between an outer wall of the pressure ring and an inner wall of the lower detection base as well as a portion of the sensor housing.

[0008] A vent duct is provided in a wall of the detection seat, and the diaphragm inner cavity communicates with the diaphragm outer cavity through the vent duct.

[0009] The detection cover is further provided with a gas inlet hole and a leak detection hole. The gas inlet hole communicates with the diaphragm inner cavity, and the leak detection hole communicates with the leak detection cavity [0010] A micro vacuum pump communicates with the gas inlet hole, and the micro vacuum pump is configured to vacuumize the inner cavity of the detection seat.

[0011] A helium supply valve communicates with the gas inlet hole, and the helium supply valve further communicates with a helium storage tank. When the helium supply valve is opened, the helium storage tank supplies helium into the inner cavity of the detection seat.

[0012] A leak detector valve communicates with the leak detection hole, and the leak detector valve further communicates with a helium mass spectrometer leak detector When the leak detector valve is opened, the helium mass spectrometer leak detector detects helium content in the leak detection cavity.

[0013] In a feasible implementation, a first sealing ring, a second sealing ring, and a third sealing ring are further included.

[0014] The first sealing ring is disposed between the pressure ring of the pressure sensor and the inner bottom wall of the lower detection base [0015] The second sealing ring is disposed between the sensor housing and the inner wall of the lower detection base.

[0016] The third sealing ring is disposed between the detection cover and the lower detection base, and the third sealing ring is provided with a sealing hole.

[0017] The vent duct includes an upper vent duct and a lower vent duct. The upper vent duct is disposed on an inner wall of the detection cover, and the lower vent duct is disposed on the inner wall of the lower detection base. The sealing hole communicates with the upper vent duct and the lower vent duct.

[0018] In a feasible implementation, a vacuum pumping valve and a helium recovery valve are further included.

[0019] The vacuum pumping valve communicates with the micro vacuum pump. When the 25 vacuum pumping valve is opened, the micro vacuum pump vacuumizes the diaphragm inner cavity.

[0020] One end of the helium recovery valve communicates with the micro vacuum pump, and the other end communicates with the helium storage tank. When the helium recovery valve is opened, the micro vacuum pump extracts helium from the diaphragm inner cavity and the diaphragm outer cavity, and recovers the helium into the helium storage tank.

[0021] In a feasible implementation, an air supply valve and an air source are further included [0022] One end of the air supply valve communicates with the diaphragm inner cavity, and the other end communicates with the air source.

[0023] When the air supply valve is opened, the air source supplies air into the inner cavity of the detection seat.

[0024] In a feasible implementation, an air pump valve and an air pump are further included. [0025] One end of the air pump valve communicates with the leak detection hole on the detection cover, and the other end communicates with the air pump.

[0026] After the detection cover is separated from the lower detection base, the air pump valve is opened and the air pump is started, so that helium residual in the leak detection hole on the detection cover may be extracted.

[0027] In a feasible implementation, a pressure transducer is further included. The pressure transducer is disposed between the gas inlet hole on the detection cover and the helium supply valve, and is configured to detect pressure of helium supplied in the diaphragm inner cavity [0028] In a feasible implementation, a three-axis sliding platform module and a loading tray are further included.

[0029] The three-axis sliding platform module is provided with a detection cover clamping tool, and the detection cover clamping tool is configured to fix the detection cover.

[0030] The loading tray is provided with several mounting sockets, and the mounting sockets are configured to place the lower detection base.

[0031] In a feasible implementation, a measurement and control master and a controller are further included.

[0032] The three-axis sliding platform module is further provided with an upper locator, and the loading tray is further provided with a lower locator. The upper locator is in a signal connection to the lower locator. The controller is in signal connections to the three-axis sliding platform module and the upper locator. The controller is configured to control the three-axis sliding platform module to move the detection cover clamping tool.

[0033] The upper locator is configured to send a positioning signal when a distance between the upper locator and the lower locator meets a preset distance.

[0034] The controller is configured to obtain the positioning signal, record a position coordinate of the upper locator based on the positioning signal, and take the position coordinate as reference for controlling the three-axis sliding platform module to move the detection cover clamping tool.

[0035] The measurement and control master is also in a signal connection to the controller.

The measurement and control master is configured to control operations of the controller through human-machine interaction.

[0036] In a feasible implementation, a conveyor belt is further included.

[0037] The controller is in a signal connection to the conveyor belt, and is further configured to control start and stop of the conveyor belt.

[0038] The conveyor belt is provided with several laying areas that are evenly distributed according to fixed distances. The laying areas are configured to place the loading tray, and the conveyor belt is configured to transfer the loading tray to a position for detection that is below the three-axis sliding platform module.

[0039] When the conveyor belt moves by one of the fixed distances, the controller controls the conveyor belt to stop, and then controls the three-axis sliding platform module to move the detection cover clamping tool to perform leak detection on all to-be-tested pressure sensors on the current loading tray [0040] After the leak detection operations on all the to-be-tested pressure sensors on the current loading tray are completed, the controller controls the conveyor belt to start and then stop after moving by one of the fixed distances. In this case, a next loading tray reaches the position for detection.

[0041] A leak detection method for a weld of a corrugated diaphragm of a pressure sensor is provided in a second aspect of this application, which is applied to any one of the foregoing leak detection apparatuses for a weld of a corrugated diaphragm of a pressure sensor. The leak detection method for a weld includes: [0042] tightly engaging a detection cover with a lower detection base; [0043] starting a micro vacuum pump to extract air from a diaphragm inner cavity and a diaphragm outer cavity; [0044] closing the micro vacuum pump and opening a helium supply valve, to supply helium in a helium storage tank into the diaphragm inner cavity and the diaphragm outer cavity through pressure differences between the helium storage tank and the diaphragm inner cavity and the diaphragm outer cavity; [0045] closing the helium supply valve and opening a leak detector valve, to vacuumize a leak detection cavity via a helium mass spectrometer leak detector, where a next step is performed after the helium mass spectrometer leak detector detects that a vacuum degree of the leak detection cavity reaches a preset value within preset duration; and if the helium mass spectrometer leak detector detects that the vacuum degree of the leak detection cavity does not reach the preset value within the preset duration, it indicates that there is a leak source in the weld of the corrugated diaphragm of the pressure sensor that is currently detected; and [0046] performing helium detection on the leak detection cavity via the helium mass spectrometer leak detector, where if' a helium detection result is that helium is detected, it indicates that there is a leak source in the weld of the corrugated diaphragm of the pressure sensor that is currently detected; and if a helium detection result signal is that no helium is detected, it indicates that there is no leak source in the weld of the pressure sensor within the lower detection base that is detected at this time.

[0047] It may be learned from the foregoing technical solutions that a leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor is provided in the first aspect of this application, including a detection seat. The detection seat includes the detection cover and the lower detection base. The lower detection base is configured to place the pressure sensor to-be-detected. After the detection cover is engaged with the lower detection base, in the inner cavity of the detection seat, the diaphragm inner cavity is formed between the metal corrugated diaphragm on the pressure sensor and the detection cover, and the diaphragm outer cavity is formed between the metal corrugated diaphragm and the inner wall of the pressure ring on the pressure sensor. The leak detection cavity is formed between the outer wall of the pressure ring and the inner wall of the lower detection base and a portion of the sensor housing. The micro vacuum pump and the helium storage tank communicate with the gas inlet hole. The helium mass spectrometer leak detector communicates with the leak detection hole. The diaphragm inner cavity and the diaphragm outer cavity on two sides of the metal corrugated diaphragm may be enabled to communicate with each other via the detection seat, so that the two sides of the metal corrugated diaphragm have same pressure. The leak detection cavity is isolated from the diaphragm inner cavity and the diaphragm outer cavity Whether helium leak exists in the leak detection cavity may be detected via the helium mass spectrometer leak detector, to further determine whether there is a leak source at a position of the weld. A leak detection method for a weld of a corrugated diaphragm of a pressure sensor is provided in the second aspect of this application. Leak detection may be performed on the weld before silicone oil is filled. According to this application, work efficiency and accuracy of leak detection may be greatly improved by use of the apparatus. Meanwhile, performing leak detection before the silicone oil is filled saves working hours for filling the silicone oil and materials required by working procedures.

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Accompanying drawings herein are incorporated into the specification and constitute a part of the specification, show embodiments in accordance with the embodiments of the present invention, and are used to explain the principle of the embodiments of the present invention together with the specification. Apparently the accompanying drawings in the description below merely illustrate some of the embodiments of the present invention, and other accompanying drawings may also be obtained by one of ordinary skills in the art according to these accompanying drawings without an effective effort.

[0049] FIG I is a sectional view of a pressure sensor; [0050] FIG 2 is a sectional view of a detection seat according to an exemplary embodiment of this application; [0051] FIG 3 is a schematic diagram of a connection structure of a leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor according to an exemplary embodiment of this application, [0052] FIG 4 is a schematic flowchart of a leak detection method for a weld of a corrugated diaphragm of a pressure sensor according to this application; and [0053] FIG 5 is a schematic diagram of an overall configuration of an apparatus according to an exemplary embodiment of this application.

[0054] Reference Numbers: [0055] 1. Measurement and control master; 2. Controller; 3. Loading tray; 4. Detection seat; 5. Air pump; 6. Three-axis sliding platform module; 7. Air source; 8. Helium mass spectrometer leak detector; 9. Micro vacuum pump; 10. Helium storage tank; 11. Diaphragm inner cavity; 12. Diaphragm outer cavity; 13. Leak detection cavity; 14. Pressure transducer; 15. Conveyor belt; 31. Mounting socket; 32. Lower locator; 41. Detection cover; 42. Lower detection base; 43.

Vent duct; 44. Sensor holder; 51. Air pump valve; 61. Detection cover clamping tool; 62. Upper locator; 71. Air supply valve; 81. Leak detector valve; 91. Vacuum pumping valve; 92. Helium recovery valve; 101. Helium supply valve; 411. Gas inlet hole; 412. Leak detection hole; 421. First sealing ring; 422. Second sealing ring; 423. Third sealing ring; 423a. Sealing hole; 431.

Upper vent duct; 432. Lower vent duct; 100. Pressure sensitive chip; 200. Oil filler port. 300.

Pressure ring; 400. Metal corrugated diaphragm; 500. Sensor housing.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0056] Exemplary implementations are described below more comprehensively with reference to the accompanying drawings. However, the exemplary implementations can be implemented in a plurality of forms and should not be understood as being limited to examples elaborated herein. On the contrary, these implementations are provided to make the embodiments of the present invention more comprehensive and complete, and comprehensively convey the concept of the exemplary implementations to a person skilled in the art. The features, structures, or characteristics described herein may be combined in one or more implementations in any suitable manner. In the following description, many specific details are provided to provide full understanding to the embodiments of the present invention.

[0057] A pressure sensor is one of the most widely used sensors in industrial fields. To isolate a pressure sensitive chip from a tested medium, typical pressure sensors all use metal corrugated diaphragms for isolation. As shown in FIG 1, FIG 1 is a sectional view of a pressure sensor that includes a pressure sensitive chip 100, an oil filler port 200, a pressure ring 300, a metal corrugated diaphragm 400, and a sensor housing 500. Silicone oil is filled between the metal corrugated diaphragm 400 and the pressure sensitive chip 100 through the oil filler port 200. The metal corrugated diaphragm 400 not only serves as a medium for isolation, but also transmits pressure to the pressure sensitive chip 100 in a loss-less manner.

[0058] A thickness of the metal corrugated diaphragm 400 is generally between 3 pm and 30 jtm. In practical production, the metal corrugated diaphragm 400 is usually clamped between the pressure ring 300 and the sensor housing 500. The pressure ring 300, the metal corrugated diaphragm 400, and the sensor housing 500 are welded together via laser, electron beams, or plasma, or in other manners. A welding the metal corrugated diaphragm 400 is an important process during production of a pressure sensor, and a quality of welding determines performance of the whole sensor. In production, slight leaks frequently occur in a weld due to poor diaphragm welding, and oil leak occurs after silicone oil is filled. This may cause the entire sensor to be rejected, which reduces a qualification ratio of products.

[0059] Currently, most detection methods for detecting a leak for a weld of the metal corrugated diaphragm 400 of the pressure sensor are performed in the following manner: silicone oil is first filled, and then leakage of silicone oil is manually detected via a high-power microscope. However, methods as such have poor detection accuracy, low detection efficiency, and missing or erroneous detections of oil leakage may often occur.

[0060] On the other hand, diaphragm welding is generally performed prior to silicone oil filling and sensor testing. Most leak sources in welds of the diaphragms are small, and it is difficult to detect leak sources after welding; or it is even impossible be detect leak sources after the silicone oil is filled. Oil leak may only occur for the sensor during a low-temperature environmental testing phase of the sensor. However, at this time, oil filling and a portion of testing procedures have been completed for the sensor, and the leak in the weld of the diaphragm inevitably causes wastes in labor power, material resources, and financial resources. [0061] Compared with leak detections for welds in other diaphragm types, a difficulty in leak detection for welds in metal corrugated diaphragm is that a method of applying pressure to one side of the diaphragm and using the other side of the diaphragm to detect leak cannot be used.

Rather, it needs to be ensured that pressure on both sides of the metal corrugated diaphragm is the same in the entire leak detection process, or otherwise the diaphragm may deform or even may be damaged during the leak detection. Therefore, leak detection for welds of a metal corrugated diaphragm of a pressure sensor needs to be performed manually with a high-power microscope, [0062] It may be learned from the foregoing background that the present invention is intended to provide a leak detection apparatus and detection method for a weld of a corrugated diaphragm of a pressure sensor, which may provide good leak detection effects and high leak detection efficiency, is easy for assembly, and is convenient for use.

[0063] A leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor is provided in a first aspect of an embodiment of this application, as shown in FIG 1, FIG 2, and FIG S. FIG 2 is a sectional view of a detection seat according to an exemplary embodiment of this application, and FIG S is a schematic diagram of an entire structure of an apparatus according to an exemplary embodiment of this application. The apparatus includes a detection seat 4. The detection seat 4 includes a detection cover 41 and a lower detection base 42 that are engaged with each other. An inner activity of the detection seat 4 may be enclosed by the detection cover 41 and the lower detection base 42. The inner cavity of the detection seat 4 is configured to place a pressure sensor to-be-detected. The pressure sensor is fixed onto an inner bottom wall of the lower detection base 42 via a sensor holder 44. A diaphragm inner cavity 11 is formed between a metal corrugated diaphragm 400 of the pressure sensor and the detection cover 41. A diaphragm outer cavity 12 is formed between the metal corrugated diaphragm 400 and an inner wall of a pressure ring 300. A leak detection cavity 13 is formed between an outer wall of the pressure ring 300 and an inner wall of the lower detection base 42 as well as a portion of a sensor housing 500.

[0064] The metal corrugated diaphragm 400 is disposed between the sensor housing 500 and the pressure ring 300. Welding points between the metal corrugated diaphragm 400 and the pressure ring 300 are located on an inner wall of the leak detection cavity 13. Therefore, if a welding problem occurs at welding points, this problem may be found by checking/performing a detection test on the leak detection activity 13.

[0065] A vent duct 43 is disposed in walls of the detection seat 4. The diaphragm inner cavity 11 is communicated with the diaphragm outer cavity 12 through the vent duct 43. via the vent duct 43, smooth air flow in the diaphragm inner cavity 11 and the diaphragm outer cavity 12 may be ensured, so that pressure on both sides of the metal corrugated diaphragm 400 is the same. Therefore, the diaphragm would not deform or be damaged during detection.

[0066] The detection cover 41 is further provided with a gas inlet hole 411 and a leak detection hole 412. The gas inlet hole 411 communicates with the diaphragm inner cavity 11, and the leak detection hole 412 communicates with the leak detection cavity 13.

[0067] A micro vacuum pump 9 communicates with the gas inlet hole 411, and is configured to vacuumize the inner cavity of the detection seat 4. During vacuum pumping, through the gas inlet hole 411, only air in the diaphragm inner cavity 11 and the diaphragm outer cavity 12 may be drawn out, while air in the leak detection cavity 13 would not be drawn out.

[0068] A helium supply valve 101 communicating with the gas inlet hole 411 is further communicated with a helium storage tank 10. When the helium supply valve 101 is opened, the helium storage tank 10 supplies helium into the inner cavity of the detection seat 4. In this case, helium is supplied into the diaphragm inner cavity 11 and the diaphragm outer cavity 12 through the gas inlet hole 411, while no helium enters the leak detection cavity 13.

[0069] A leak detector valve 81 communicates with the leak detection hole 412, and is further communicated with a helium mass spectrometer leak detector 8. When the leak detector valve 81 is opened, the helium mass spectrometer leak detector 8 may detect content of helium in the leak detection cavity 13. It may be understood that a detection of helium indicates that helium is leaked into the leak detection cavity 13, which indicates that there is a leakage source in the weld. If no helium is detected, it indicates that no helium is leaked into the leak detection cavity 13, which indicates that quality of the weld may meet the demand.

[0070] It may be learned from the foregoing technical solutions that a leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor is provided according to the first aspect of this application; the leak detection apparatus includes a detection seat 4. The detection seat 4 includes the detection cover 41 and the lower detection base 42. The lower detection base 42 is configured to place the pressure sensor to-be-detected. After the detection cover 41 is engaged with the lower detection base 42, in the inner cavity of the detection seat 4, a diaphragm inner cavity 11 is formed between the metal corrugated diaphragm 400 of the pressure sensor and the detection cover 4, and a diaphragm outer cavity 12 is formed between the metal corrugated diaphragm 400 and an inner wall of the pressure ring 300 of the pressure sensor. A leak detection cavity 13 is formed between the outer wall of the pressure ring 300 and the inner wall of the lower detection base 42 as well as a portion of the sensor housing 500. A micro vacuum pump 9 and a helium storage tank 10 communicate with the diaphragm inner cavity 11 and the diaphragm outer cavity 12. A helium mass spectrometer leak detector 8 communicates with the leak detection cavity 13. The diaphragm inner cavity 11 and the diaphragm outer cavity 12 on two sides of the metal corrugated diaphragm 400 may be communicated with each other via the detection seat 4, so that the two sides of the metal corrugated diaphragm 400 are provided with the same pressure. The leak detection cavity 13 is isolated from the diaphragm inner cavity 11 and the diaphragm outer cavity 12. Whether helium leak exists in the leak detection cavity 13 may be detected via the helium mass spectrometer leak detector 8, to further determine whether there is a leak source at a welding point.

[0071] A leak detection method for a weld of a corrugated diaphragm of a pressure sensor is provided according to another aspect of this application, which is applied to the leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor described above, as shown in FIG 4. FIG 4 is a schematic flowchart of a leak detection method for a weld of a corrugated diaphragm of a pressure sensor according to this application. The leak detection method for a weld includes the following steps.

[0072] St. Engaging a detection cover 41 with a lower detection base 42 tightly to ensure that an internal space of the detection seat 4 is sealed and the pressure to-be-detected is securely fixed, so that no leak may occur due to misalignment [0073] S2. Starting a micro vacuum pump 9 to pump out air from a diaphragm inner cavity 11 and a diaphragm outer cavity 12. In this case, pressure on two sides of a metal corrugated diaphragm 400 maintains the same, and a pumping-out of air may facilitate entry of helium into the diaphragm inner cavity 11 and the diaphragm outer cavity U. [0074] S3. Closing the micro vacuum pump 9 and opening a helium supply valve 101, to supply helium in a helium storage tank 10 into the diaphragm inner cavity 11 and the diaphragm outer cavity 12 through pressure differences between the helium storage tank 10 and the diaphragm inner cavity 11/the diaphragm outer cavity 12. In this case, the pressure on the two sides of the metal corrugated diaphragm 400 still maintains the same, and no damage would be caused to the metal corrugated diaphragm 400.

[0075] S4. Closing the helium supply valve 101 and opening a leak detector valve 81, to vacuumize a leak detection cavity 13 via a helium mass spectrometer leak detector 8. A next step S5 is performed in case the helium mass spectrometer leak detector 8 determines that a vacuum degree in the leak detection cavity 13 reaches a preset value within a preset time duration. If even after the preset time duration, the helium mass spectrometer leak detector 8 still finds that the vacuum degree in the leak detection cavity 13 does not reach the preset value, it is determined that there is a large leakage source in the weld of the corrugated diaphragm of the pressure sensor that is currently under detection.

[0076] By presetting time interval as described above, an unqualified vacuum degree may be detected in a short period time, which indicates that there is a large leakage source in the weld. In this case, it may be determined that the pressure sensor is not qualified without further performing helium detection. It may be understood that it does not necessarily indicate that there is no leakage source in the weld even though a value of the vacuum degree meets requirements, because there is a possibility that the leakage source is small and helium leaks slowly, which may also make the value of the vacuum degree meet the requirement. In this case, further detection is required. Generally, the preset time duration is 30 seconds, but different preset time duration may be set according to actual situations. This is not specifically limited in this application.

[0077] Si. Performing helium detection on the leak detection cavity 13 via the helium mass spectrometer leak detector 8. If the detection result indicates that helium is detected, it means that there is a leakage source in the weld of the metal corrugated diaphragm 400 of the detected pressure sensor in the current lower detection base 42. If a helium detection result signal given shows that no helium is detected, it indicates that there is no leakage source in the weld of the metal corrugated diaphragm 400 of the detected pressure sensor in the current lower detection base 42. When the vacuum degree meets the requirements, there is no residual air in the leak detection cavity 13; thus, it may be determined that it is the diaphragm inner cavity 11 and the diaphragm outer cavity 12 that helium detected by the helium mass spectrometer leak detector 8 leaks from. Therefore, it may be determined that there is a leakage source in the weld of the metal corrugated diaphragm 400.

[0078] The leak detection method for a weld of a corrugated diaphragm of a pressure sensor is provided in a second aspect of this application. Leak detection may be performed on the weld before silicone oil is filled. According to this application, work efficiency and accuracy of the leak detection may be greatly improved via the apparatus for leak detection. Meanwhile, performing leak detection before the silicone oil is filled saves working hours needed for filling the silicone oil and materials required during working procedures.

[0079] In some embodiments of this application, referring to FIG. 2 again, the leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor further includes: [0080] a first sealing ring 421 that is disposed between the pressure ring 300 of the pressure sensor and the inner bottom wall of the lower detection base 42; [0081] a second sealing ring 422 that is disposed between the sensor housing 500 and the inner wall of the lower detection base 42; and [0082] a third sealing ring 423 that is disposed between the detection cover 41 and the lower detection base 42, with a sealing hole 423a being provided in the third sealing ring 423.

[0083] The vent duct 43 includes an upper vent duct 431 and a lower vent duct 432. The upper vent duct 431 is provided in an inner wall of the detection cover 41, and the lower vent duct 432 is provided in the inner wall of the lower detection base 42. The sealing hole 423a communicates with the upper vent duct 431 and the lower vent duct 432.

[0084] In the embodiments, use of the first sealing ring 421 and the second sealing ring 422 may ensure that the diaphragm inner cavity 11 and the diaphragm outer cavity 12 are isolated from the leak detection cavity 13 in a sealing manner, ensure that the diaphragm inner cavity 11 and the diaphragm outer cavity 12 are sealed with respect to all other parts except for communicating with the gas inlet hole 411, and ensure that the leak detection cavity 13 is sealed with respect to all other parts except for communicating with the leak detection hole 412.

Therefore, there would be no gas seepage that may affect the leakage detection result. The third sealing ring 423 may ensure sealing isolation from the external environment when the detection cover 41 is engaged with the lower detection base 42. Meanwhile, the sealing hole 423a provided in the third sealing ring 423 may communicate the upper vent duct 431 with the lower vent duct 432. Therefore, a continuity of the vent duct 43 will not be affected.

[0085] In some embodiments of this application, referring to FIG 2 and FIG 5 again, the leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor further includes a vacuum pumping valve 91 and a helium recovery valve 92.

[0086] The vacuum pumping valve 91 communicates with the micro vacuum pump 9. When the vacuum pumping valve 91 is opened and the helium recovery valve 92 is closed, the micro 30 vacuum pump 9 may be started to vacuumize the diaphragm inner cavity 11. Vacuum pumping effects may be controlled by controlling opening or closing of the vacuum pumping valve 91, the helium recovery valve 92, and the micro vacuum pump 9.

[0087] One end of the helium recovery valve 92 is connected to the micro vacuum pump 9, and the other end is connected to the helium storage tank 10. When the helium recovery valve 92 is opened and the vacuum pumping valve 91 is closed, the micro vacuum pump 9 may be started to draw out helium from the diaphragm inner cavity 11 and the diaphragm outer cavity 12, and circulates the helium into the helium storage tank 10 for reuse in next leak detection, thereby saving helium and avoiding wastes.

[0088] Referring to FIG. 2 and FIG. 5 again, in some embodiments of this application, the apparatus further includes an air pump valve 51 and an air pump 5. One end of the air pump valve 51 communicates with the leak detection hole 412 in the detection cover 41, and the other end communicates with the air pump 5. After the detection cover 41 is separated from the lower detection base 42, the air pump valve 51 is opened and the air pump 5 is started, so that helium residual in the leak detection hole 412 in the detection cover 41 may be drawn out, thereby avoiding affecting a testing result of the next leakage detection [0089] Referring to FIG 2 and FIGS again, in some embodiments of this application, the apparatus further includes an air supply valve 71 and an air source 7. One end of the air supply valve 71 communicates with the gas inlet hole 411 in the detection cover 41, and the other end communicates with the air source 7. The air supply valve 71 is opened after the leakage detection operation for the pressure sensor to-be-detected is completed and the helium is recovered. The air source 7 supplies air into the inner cavity of the detection seat 4, so that the inner cavity of the detection seat 4 may be restored to an atmosphere pressure, thereby facilitating separation of the detection cover 41 from the lower detection base 42. The air source 7 may be atmosphere in the environment, or may be an air pipeline, a container, and other manners; this is not particularly specified herein [0090] Referring to FIG 2 and FIG 5 again, in some embodiments of this application, the apparatus further includes a pressure transducer 14. The pressure transducer 14 is disposed between the gas inlet hole 411 in the detection cover 41 and the helium supply valve 101. The pressure transducer 14 is configured to detect pressure of helium supplied in the diaphragm inner cavity 11, and adjust an amount of the helium supplied into the diaphragm inner cavity 11, so as to avoid an excessive or insufficient amount of helium is supplied, which will adversely affect the leakage detection.

[0091] In some embodiments of this application, referring to FIG 3 which is a schematic diagram of a connection structure of a leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor according to an exemplary embodiment of this application, the apparatus further includes a three-axis sliding platform module 6 and a loading tray 3.

[0092] The three-axis sliding platform module 6 is provided with a detection cover clamping tool 61 that is configured to fix the detection cover 41. The loading tray 3 is provided with several mounting sockets 31 that are configured to locate the lower detection base 42. Batch leakage detection tests may be performed for pressure sensors to-be-detected via the three-axis sliding platform module 6 and the loading tray 3, thereby improving leak detection efficiency. [0093] In some embodiments of this application, referring to FIG 3 and FIG 5 again, the apparatus further includes: [0094] a measurement and control master 1 and a controller 2.

[0095] The three-axis sliding platform module 6 is further provided with an upper locator 62, and the loading tray 3 is further provided with a lower locator 32. Signals may be communicated between the upper locator 62 and the lower locator 32. The controller 2 is in signal-communication with both the three-axis sliding platform module 6 and the upper locator 62. The controller 2 is configured to control the three-axis sliding platform module 6 to move the detection cover clamping tool 61. The upper locator 62 is configured to send a positioning signal when a distance between the upper locator 62 and the lower locator 32 reaches a preset value. The controller 2 is configured to obtain the positioning signal, record a position coordinate of the upper locator 62 based on the positioning signal, and take the position coordinate as reference for controlling a movement of the three-axis sliding platform module 6.

Subsequently, the position coordinate is used as basis for the controller 2 to control the three-axis sliding platform module 6 to move the detection cover clamping tool 61 in three directions upward-downward, forward-backward, and left-right, so as to achieve an alignment and docking of the detection cover 41 with all lower detection bases 42 on the loading tray 3. In the embodiments of this application, the three-axis sliding platform module 6 is controlled, via the controller 2, to move the detection cover clamping tool 61 in three directions: upward-downward, forward-backward, and left-right. When the upper locator 62 on the detection cover damping tool 61 moves and a distance between the upper locator 62 and the lower locator 32 is within a preset range, the upper locator 62 sends the positioning signal to the controller 2. At this time, the detection cover 41 is in a position facing towards a first lower detection base 42 on the loading tray 3. The controller 2 controls the three-axis sliding platform module 6 to move in a direction close to the loading tray 3, so as to drive the detection cover 41 to move downward. Finally, the detection cover 41 is tightly engaged with the first lower detection base 42 on the loading tray 3. Because relative positions between the lower detection bases 42 on the loading tray 3 are fixed, based on the reference of the three-axis sliding platform module 6, the three-axis sliding platform module 6 is controlled via the controller 2 to move by the preset distance in three directions: upward-downward, forward-backward, and left-right. In this way, the detection cover 41 may be accurately aligned and docked with each lower detection base 42 on the loading tray 3.

[0096] It may be understood that the controller 2 may also control opening and closing of various valves; the measurement and control master 1 is also in a signal-communication with the controller 2. The measurement and control master I is configured to control operations of the controller 2 through human-machine interaction. An operator may control and confirm a state of the leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor via the measurement and control master 1.

[0097] In some embodiments of this application, referring to FIG 3 and FIG 5 again, the apparatus further includes a conveyor belt 15. The controller 2 is in signal-communication with the conveyor belt 15. The controller 2 is further configured to control a start and stop of the conveyor belt 15. The conveyor belt 15 is provided with several laying areas that are evenly distributed according to fixed distances. The laying areas are configured to place the loading trays 3. The conveyor belt 15 is configured to transfer the loading trays 3 to a position for detection below the three-axis sliding platform module 6. After the conveyor belt 15 moves a set distance, the controller 2 controls the conveyor belt 15 to stop, and controls the three-axis sliding platform module 6 to move the detection cover clamping tool 61 to perform leakage detection on all pressure sensors to-be-tested provided on the current loading tray 3. After leakage detection operations for all the pressure sensors to-be-tested on the current loading tray 3 have been completed, the controller 2 controls and initiates the conveyor belt 15, and the conveyor belt 15 would stop after moving across the set distance. In this case, a next loading tray 3 would reach the position for detection. According to this application, use of the conveyor belt 15 may make the leak detection for the weld of the corrugated diaphragm of the pressure sensor semi-automatic, thus greatly saving labor power and improving detection efficiency.

[0098] Based on the leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor in the foregoing embodiments, in some embodiments of this application, the leak detection method for a weld of a corrugated diaphragm of a pressure sensor includes the following steps [0099] S100. Assembling all pressure sensors to-be-detected into lower detection bases 42 sequentially, and mounting the lower detection bases 42 onto mounting sockets 31 on loading trays 3.

[00100] S200 Placing the assembled loading trays 3 onto preset areas on a conveyor belt 15, sequentially.

[00101] S300 Starting a controller 2 via a measurement and control master 1 to control the conveyor belt 15 to move. After the conveyor belt 15 has moved across a set distance, one loading tray 3 on the conveyor belt 15 would be positioned in an area below a three-axis sliding platform module 6 [00102] S400. Controlling the controller 2, via the measurement and control master 1, to start an automatic leak detection process for a weld of a corrugated diaphragm of a pressure sensor.

The automatic leak detection process is as follows.

[00103] S401. Controlling, via the controller 2, the three-axis sliding platform module 6 to move a detection cover clamping tool 17 in three directions: upward-downward, forward-backward, and left-right. When an upper locator 62 on the detection cover clamping tool 17 moves to such a position that a distance between the upper locator 62 and the lower locator 32 is within a preset range, the upper locator 62 sends a positioning signal to the controller 2. At this time, a detection cover 41 is facing towards a first lower detection base 42 on the loading tray 3. The controller 2 records a position coordinate of the three-axis sliding platform module 6 at this time, and take the position coordinate as movement reference for the three-axis sliding platform module 6.

[00104] S402. Controlling, via the controller 2, the three-axis sliding platform module 6 to move downward by a preset distance, so as to drive the detection cover 41 to move downward. Finally, the detection cover 41 is tightly engaged with the lower detection base 42.

[00105] S403. Opening a vacuum pumping valve 91, closing a helium recovery valve 92, and starting a micro vacuum pump 9 via the controller 2, to draw out air from a diaphragm inner cavity 11 and a diaphragm outer cavity 12, and then closing the vacuum pumping valve 91. [00106] S404. Opening a helium supply valve 101 via the controller 2, to supply helium in a helium storage tank 10 into the diaphragm inner cavity 11 and the diaphragm outer cavity 12 by making use of pressure differences between the helium storage tank 10 and the diaphragm inner cavity 11/the diaphragm outer cavity 12; detecting helium pressure in the diaphragm inner cavity 11 and the diaphragm outer cavity 12 in a real-time manner via a pressure transducer 14; and closing the helium supply valve 101 when a pressure value detected by the pressure transducer 14 reaches a preset pressure value.

[00107] S405. Opening a leak detector valve 81 and closing an air pump valve 51 via the controller 2; and starting, via the controller 2, a helium mass spectrometer leak detector 8 to vacuumize the leak detection cavity 13.

[00108] S406. Collecting a vacuum degree signal output by the helium mass spectrometer leak detector 8 via the controller 2. Step S407 is performed in case that a vacuum degree in the leak detection cavity 13 detected by the helium mass spectrometer leak detector 8 reaches a preset value within a preset time duration. On the other hand, if the vacuum degree in the leak detection cavity 13 detected by the helium mass spectrometer leak detector 8 does not reach the preset value within the preset time duration, it is determined that there is a leak source in the weld of the corrugated diaphragm of the pressure sensor currently under detection. The controller 2 records a numbering of the loading tray 3 on which the pressure sensor currently under detection is located, as well as a numbering of the lower detection base 42 in the loading tray 3; step S408 is performed thereafter.

[00109] S407. Collecting a helium gas detection result signal output by the helium mass spectrometer leak detector 8 via the controller 2. If the helium detection result indicates that helium is detected, it is determined that there is a leak source in the weld of the pressure sensor within the lower detection base 42 currently under detection. The controller 2 records the numbering of the loading tray 3 on which the pressure sensor currently under detection is located, as well as the numbering of the lower detection base 42 in the loading tray 3. If the helium detection result signal indicates that no helium is detected, it is determined that there is no leak source in the weld of the pressure sensor within the lower detection base 42 currently under detection.

[00110] S408. Closing the leak detector valve 81, opening the helium recovery valve 92, and starting the micro vacuum pump 9 via the controller 2, to draw/suck the helium in the diaphragm inner cavity 11 and the diaphragm outer cavity 12 back into the helium storage tank 10; closing the helium recovery valve 92 after helium suction is completed.

[00111] S409. Opening an air supply valve 71 via the controller 2, to supply air in an air source 7 into the diaphragm inner cavity 11 and the diaphragm outer cavity 12 making use of pressure differences between the air source 7 and the diaphragm inner cavity 11/the diaphragm outer cavity 12; closing the air supply valve 71 after said operation is completed.

[00112] S410. Controlling, via the controller 2, the three-axis sliding platform module 6 to move upward by a preset distance, so that the detection cover 41 is separated from the lower detection base 42.

[00113] S411. Opening the air pump valve 51 and starting an air pump 5 via the controller 2, to draw out helium residual in the leak detection hole 412 on the detection cover 41 via the air pump 5.

[00114] S412. Determining, via the controller 2, if all the pressure sensors to-be-detected on the current loading tray 3 have been detected; performing step S413 if not all the pressure sensors to-be-detected have been detected; and performing step S414 if all the pressure sensors to-be-detected have been detected.

[00115] S413. Controlling, via the controller 2, the three-axis sliding platform module 6 to move by preset distances in forward-backward and left-right directions, and controlling the three-axis sliding platform module 6 to move downwardly by a preset distance, so that the detection cover 41 is tightly engaged with a next lower detection base 42 on the loading tray 3; performing steps S403 to S412 again.

[00116] S414: Transferring numberings of the loading trays 3 on which all pressure sensors with leakage sources in the welds of the diaphragms as well as numberings of respective lower detection bases 42 in the loading trays 3 to the measurement and control master 1 via the controller 2. The measurement and control master 1 displays and stores detection results of an detected pressure sensors on the current loading tray 3.

[00117] S500: Repeating steps S300 to S400 until all pressure sensors on the loading trays 3 on the conveyor belt 15 have been detected, and ending the leak detection process.

[00118] It may be learned from the foregoing embodiments that a leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor is provided in a first aspect of this application. The leak detection apparatus includes a detection seat. The detection seat includes a detection cover and a lower detection base. The lower detection base is configured to assemble the pressure sensors to-be-detected. After the detection cover is engaged with the lower detection base, in an inner cavity of the detection seat, an diaphragm inner cavity is formed between the metal corrugated diaphragm on the pressure sensor and the detection cover, and a diaphragm outer cavity is formed between the metal corrugated diaphragm and an inner wall of a pressure ring on the pressure sensor. A leak detection cavity is formed between the outer wall of the pressure ring and an inner wall of the lower detection base and a portion of the sensor housing. A micro vacuum pump and a helium storage tank communicate with the diaphragm inner cavity and the diaphragm outer cavity A helium mass spectrometer leak detector communicates with a leak detection hole. The diaphragm inner cavity and the diaphragm outer cavity on two sides of the metal corrugated diaphragm may be communicated with each other via the detection seat, so that the two sides of the metal corrugated diaphragm are provided with the same pressure. The leak detection cavity is isolated from the diaphragm inner cavity and the diaphragm outer cavity Whether helium leak exists in the leak detection cavity may be detected via the helium mass spectrometer leak detector, so to further determine whether there is a leak source on the weld. A leak detection method for a weld of a corrugated diaphragm of a pressure sensor is provided in the second aspect of this application. Leak detection may be performed on the weld before silicone oil is filled. According to this application, work efficiency and accuracy of the leak detection may be greatly improved through leak detection via the apparatus. Meanwhile, performing leak detection before the silicone oil is filled may save working hours for filling the silicone oil and materials required by working procedures.

[00119] A person skilled in the art would easily conceive of other implementation solutions of this disclosure after considering the specification and practicing this disclosure disclosed herein. This application is intended to cover any variation, use, or adaptive change of this disclosure. These variations, uses, or adaptive changes follow the general principle of this disclosure and include the common general knowledge or common technical means in this technical filed that is not disclosed in this disclosure. The specification and the embodiments are merely considered as exemplary, and the actual scope and spirit of this disclosure are indicated in the following claims [00120] It should be understood that this disclosure is not limited to the exact structure that is described above and is shown in the figures, and various modifications and changes may be made thereto, without departing from the scope thereof The scope of this disclosure is merely limited by the appended claims.

Claims (10)

1. WHAT IS CLAIMED IS: 1. A leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor, comprising a detection seat (4), wherein the detection seat (4) comprises a detection cover (41) and a lower detection base (42) that are engaged with each other, and an inner activity of the detection seat (4) is enclosed by the detection cover (41) and the lower detection base (42) together, wherein the pressure sensor comprises a pressure sensitive chip (100), an oil filler port (200), a pressure ring (300), a metal corrugated diaphragm (400), and a sensor housing (500); wherein the inner cavity of the detection seat (4) is configured to place a pressure sensor to-be-detected that is fixed on an inner bottom wall of the lower detection base (42) via a sensor holder (44); wherein a diaphragm inner cavity (11) is formed between the metal corrugated diaphragm (400) of the pressure sensor and the detection cover (41), a diaphragm outer cavity (12) is formed between the metal corrugated diaphragm (400) and an inner wall of the pressure ring (300), and a leak detection cavity (13) is formed between an outer wall of the pressure ring (300) and an inner wall of the lower detection base (42) as well as a portion of the sensor housing (500); wherein a vent duct (43) is provided in an inner wall of the detection seat (4), and the diaphragm inner cavity (1 1) is communicated with the diaphragm outer cavity (12) via the vent duct (43); wherein the detection cover (41) is further provided with a gas inlet hole (411) and a leak detection hole (412), with the gas inlet hole (411) being communicated with the diaphragm inner cavity (11), and the leak detection hole (412) being communicated with the leak detection cavity (13); wherein the gas inlet hole (411) is communicated with a micro vacuum pump (9) that is configured to vacuumize the inner cavity of the detection seat (4), wherein the gas inlet hole (411) is communicating with a helium supply valve (101) that is further communicated with a helium storage tank (10); when the helium supply valve (101) is opened, helium is supplied from the helium storage tank (10) into the inner cavity of the detection seat (4), and wherein the leak detection hole (412) is communicated with a leak detector valve (81) that is further communicated with a helium mass spectrometer leak detector (8); when the leak detector valve (81) is opened, the helium mass spectrometer leak detector (8) detects content of helium in the leak detection cavity (13).
2. 2 The leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor according to claim 1, further comprising a first sealing ring (421), a second sealing ring (422), and a third sealing ring (423), wherein the first sealing ring (421) is disposed between the pressure ring (300) of the pressure sensor and the inner wall of the lower detection base (42); the second sealing ring (422) is disposed between the sensor housing (500) and the inner wall of the lower detection base (42), the third sealing ring (423) is disposed between the detection cover (41) and the lower detection base (42), and is provided with a sealing hole (423a); and the vent duct (43) comprises an upper vent duct (431) and a lower vent duct (432), wherein the upper vent duct (43 is provided in a wall of the detection cover (41), the lower vent duct (432) is provided in a wall of the lower detection base (42), and the sealing hole (423a) communicates with the upper vent duct (431) and the lower vent duct (432).
3. 3. The leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor according to claim 1, further comprising a vacuum pumping valve (91) and a helium recovery valve (92), wherein the vacuum pumping valve (91) is communicated with the micro vacuum pump (9); when 25 the vacuum pumping valve (91) is opened, the micro vacuum pump (9) performs vacuum-pumping for the diaphragm inner cavity (11); and one end of the helium recovery valve (92) is communicated with the micro vacuum pump (9), the other end of the helium recovery valve (92) is communicated with the helium storage tank (10); when the helium recovery valve (92) is opened, the micro vacuum pump (9) draws helium out from the diaphragm inner cavity (11) and the diaphragm outer cavity (12), and returns the helium back into the helium storage tank (10).
4. 4. The leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor according to claim 1, further comprising an air supply valve (71) and an air source (7), wherein one end of the air supply valve (71) is communicated with the diaphragm inner cavity (11), and the other end of the air supply valve (71) is communicated with the air source (7); and when the air supply valve (71) is opened air is supplied from the air source (7) into the inner cavity of the detection seat (4).
5. 5. The leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor according to claim 1, further comprising an air pump valve (5 I) and an air pump (5), wherein one end of the air pump valve (51) is communicated with the leak detection hole (412) in the detection cover (41), and the other end of the air pump valve (51) is communicated with the air pump (5); and when the air pump valve (51) is opened, the air pump (5) draws out helium residual in the leak detection hole (412) in the detection cover (41).
6. 6. The leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor according to claim I, further comprising a pressure transducer (14) that is arranged between the gas inlet hole (411) in the detection cover (41) and the helium supply valve (101), and is configured to detect pressure of helium supplied into the diaphragm inner cavity (11).
7. 7. The leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor according to claim 1, further comprising a three-axis sliding platform module (6) and a loading tray (3), wherein the three-axis sliding platform module (6) is provided with a detection cover clamping tool (61) that is used to fix the detection cover (41); and the loading tray (3) is provided with a plurality of mounting sockets (31) that are configured to place the lower detection base (42).
8. 8. The leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor according to claim 7, further comprising a measurement and control master (1) and a controller (2), wherein the three-axis sliding platform module (6) is further provided with an upper locator (62); the loading tray (3) is further provided with a lower locator (32), the upper locator (62) is in a signal-communication with the lower locator (32); the controller (2) is in a signal-communication with the three-axis sliding platform module (6) and the upper locator (62), and the controller (2) is configured to control the three-axis sliding platform module (6) to move the detection cover clamping tool (61), the upper locator (62) is configured to send a positioning signal when a distance between the upper locator (62) and the lower locator (32) reaches a preset value; the controller (2) is configured to obtain the positioning signal, record a position coordinate of the upper locator (62) based on the positioning signal, and take the position coordinate as a reference for controlling movement of the three-axis sliding platform module (6); and the measurement and control master (1) is also in a signal-communication with the controller (2), and the measurement and control master (1) is configured to control operations of the controller (2) through human-machine interaction.
9. 9 The leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor according to claim 8, further comprising a conveyor belt (15), wherein the controller (2) s inas gnal-communication with the conveyor belt (15), and is further configured to control start and stop of the conveyor belt (15), the conveyor belt (15) is provided with a plurality of laying areas that are evenly distributed according to fixed distances, wherein the laying areas are configured to place the loading trays (3); the conveyor belt (15) is configured to transfer the loading trays (3) to positions below the three-axis sliding platform module (6) for detection; after the conveyor belt (15) has moved across the fixed distance, the controller (2) controls the conveyor belt (15) to stop, and controls the three-axis sliding platform module (6) to move the detection cover clamping tool (61) so as to perform leak detection on all pressure sensors to-be-tested on the loading tray (3) currently under detection; and after leak detection operations for all the pressure sensors to-be-tested on the loading tray (3) currently under detection have been completed, the controller (2) controls the conveyor belt (15) to start moving and then stop after moving across the fixed distance, such that a next loading tray (3) reaches the position for detection
10. 10. A leak detection method for a weld of a corrugated diaphragm of a pressure sensor, wherein the method is applied to the leak detection apparatus for a weld of a corrugated diaphragm of a pressure sensor according to any one of claims 1 to 9, and the leak detection method for a weld comprises: tightly engaging a detection cover with a lower detection base, starting a micro vacuum pump to draw air out from a diaphragm inner cavity and a diaphragm outer cavity; closing the micro vacuum pump and opening a helium supply valve, to supply helium in a helium storage tank into the diaphragm inner cavity and the diaphragm outer cavity by making use of pressure differences between the helium storage tank and the diaphragm inner cavity and the diaphragm outer cavity; closing the helium supply valve and opening a leak detector valve, to vacuumize a leak detection cavity via a helium mass spectrometer leak detector, wherein a next step is performed in case that the helium mass spectrometer leak detector determined that a vacuum degree in the leak detection cavity reaches a preset value within a preset time duration; on the other hand, if' the vacuum degree in the leak detection cavity detected by the helium mass spectrometer leak detector does not reach the preset value within the preset time duration, it is determined that there is a leak source in the weld of the corrugated diaphragm of the pressure sensor that is currently under detection; performing helium detection on the leak detection cavity via the helium mass spectrometer leak detector, wherein if a helium detection result indicates that helium is detected, it is determined that there is a leak source in the weld of the corrugated diaphragm of the pressure sensor currently under detection; and if a helium detection result indicates that no helium is detected, it is determined that there is no leak source in the weld of the pressure sensor currently under detection within the lower detection base.