Piston-type vacuum detection valve for cryogenic gas cylinders

Abstract

This application discloses a piston-type vacuum detection pull valve for cryogenic gas cylinders, comprising: a valve body, a pull rod, a sealing head, and a sealing sleeve. The valve body has a movable chamber with a pull rod opening at the top of the movable chamber, a sealing opening at the bottom of the movable chamber, and a vacuum port on the side wall of the movable chamber. The sealing opening is connected to the cryogenic gas cylinder, and the vacuum port is connected to a detection device. The pull rod includes a rod portion extending vertically through the pull rod opening and a sleeve handle installed at the top of the rod portion. The rod portion extends vertically. The sealing head is threaded to the bottom end of the rod portion. The sealing head has a first position sealing the sealing opening and a second position in the movable chamber where its bottom is located above at least part of the vacuum port. The outer surface of the sealing sleeve is clearance-fitted with the side wall of the movable chamber. The sealing sleeve seals the vacuum port when the sealing head moves from the second position to the first position. The addition of a sealing sleeve to the pull rod in this application enables rapid replacement of cryogenic gas cylinders and rapid detection.

Description

Technical Field

[0001] This application relates to the field of vacuum equipment technology, and in particular to a piston-type vacuum detection valve for cryogenic gas cylinders. Background Technology

[0002] Currently, when testing the vacuum insulation layer of a vacuum-insulated gas cylinder, the testing device must first be evacuated to a lower vacuum level than the cylinder itself, thus preserving the vacuum of the insulation layer. However, when replacing the testing cylinder, ordinary vacuum valves allow atmospheric air to enter the testing device during disassembly, disrupting the vacuum environment. Furthermore, the testing device contains a molecular pump for high-vacuum extraction and an ionization gauge for vacuum detection; both have specific environmental requirements, and direct exposure to the atmosphere can damage them. Therefore, in actual testing procedures, replacing cylinders requires frequent switching of the high-vacuum baffle valve, ionization gauge, and molecular pump power, and the testing device must be re-evacuated after each cylinder replacement. This cumbersome and time-consuming process makes it impossible to quickly complete the testing of multiple cylinders. Summary of the Invention

[0003] To address the aforementioned technical problems, the purpose of this application is to provide a piston-type vacuum detection valve for cryogenic gas cylinders that can quickly detect multiple cryogenic gas cylinders without requiring repeated vacuuming.

[0004] To achieve the above objectives, this application adopts the following technical solution: a piston-type vacuum detection valve for cryogenic gas cylinders, connected to a detection device having a molecular pump, an ionization gauge, and a high-vacuum baffle valve, wherein the piston-type vacuum detection valve comprises:

[0005] The valve body has an internal movable chamber. The valve body has a pull rod opening at the top of the movable chamber, a sealing opening at the bottom of the movable chamber, and a vacuum port on the side wall of the movable chamber. The pull rod opening is a through hole. The sealing opening connects the cryogenic gas cylinder and the movable chamber. The vacuum port connects the detection device and the movable chamber.

[0006] A lever includes a rod portion passing through the lever opening and a sleeve handle installed at the top end of the rod portion. The rod portion extends in a vertical direction, and the sleeve handle is located on the upper side of the lever valve body.

[0007] A sealing head, coaxially mounted to the bottom end of the rod and threadedly connected to the bottom end of the rod, has a first position within the movable chamber that seals the sealing opening and a second position where its bottom is located at least partially above the vacuum port; and

[0008] A sealing sleeve is coaxially sleeved on the rod and located above the sealing head. The outer surface of the sealing sleeve is in clearance fit with the side wall of the movable chamber. The sealing sleeve is configured to seal the vacuum port when the sealing head moves from the second position to the first position.

[0009] In the above technical solution, a further preferred embodiment is that a limiting pin is radially inserted into the rod portion, and a limiting groove for the limiting pin to move up and down and a limiting ring groove for the limiting pin to rotate around the axis of the rod portion are provided on the side wall of the pull rod opening.

[0010] In the above technical solution, it is further preferred that the sealing opening has at least one first sealing ring groove, the at least one first sealing ring groove is arranged at intervals in the vertical direction, and a first sealing ring is installed in each of the first sealing ring grooves.

[0011] In the above technical solution, it is further preferred that the sealing head has at least one second sealing ring groove in its circumferential direction, the at least one second sealing ring groove is arranged at intervals in the vertical direction, and a second sealing ring is installed in each of the second sealing ring grooves.

[0012] In the above technical solution, it is further preferred that the diameter of the pull rod opening is smaller than the diameter of the movable chamber.

[0013] In the above technical solution, it is further preferred that the diameter of the sleeve handle is larger than the diameter of the pull rod opening.

[0014] In the above technical solution, a further preferred embodiment is that the projection of the swivel handle from top to bottom is in the shape of a plum blossom.

[0015] In the above technical solution, a pair of positioning rings are further fitted on the rod, and the pair of positioning rings are respectively arranged at the top end of the sealing sleeve and the bottom end of the sealing sleeve.

[0016] In the above technical solution, it is further preferred that the upper surface of the sealing head is provided with a threaded hole, and the bottom end of the rod is provided with an external thread that mates with the threaded hole.

[0017] Compared with the prior art, this application achieves the following beneficial effects:

[0018] This application adds a sealing sleeve to the pull rod, so that the sealing sleeve seals the detection device when the sealing head is connected to the cryogenic gas cylinder. This eliminates the need to shut down the electronic equipment and valves in the detection device and does not disrupt the vacuum environment that has already been evacuated in the detection device, thus enabling rapid replacement of cryogenic gas cylinders and rapid detection. Attached Figure Description

[0019] Figure 1 A three-dimensional structural diagram of a piston-type vacuum detection valve connected to a detection device is provided in an embodiment of this application.

[0020] Figure 2 for Figure 1 A front view of the piston-type vacuum detection valve connected to the detection device.

[0021] Figure 3 for Figure 2 A cross-sectional view of the piston-type vacuum detection valve in the first position with the sealing head in the first position;

[0022] Figure 4 for Figure 2 A cross-sectional view of the piston-type vacuum detection valve in the second position, showing the plug head in the second position.

[0023] The components are as follows: 10. Piston-type vacuum detection pull valve; 1. Pull valve body; 11. Movable chamber; 12. Pull rod port; 13. Sealing port; 14. Vacuum port; 15. First sealing ring; 16. Limiting groove; 17. Limiting ring groove; 2. Pull rod; 21. Rod part; 211. External thread; 22. Sleeve handle; 23. Positioning ring; 24. Limiting pin; 3. Sealing head; 31. Threaded hole; 4. Sealing sleeve; 5. Second sealing ring; 20. Detection device; 6. Ionization gauge; 7. High vacuum baffle valve; 8. Molecular pump; 9. Detection pipeline. Detailed Implementation

[0024] To illustrate the technical content, structural features, achieved objectives, and effects of the application in detail, the technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. In the following description, for illustrative purposes, numerous specific details are set forth to provide a detailed description of various exemplary embodiments or implementations of the invention. However, various exemplary embodiments may also be implemented without these specific details or in one or more equivalent arrangements. Furthermore, the various exemplary embodiments may differ, but are not necessarily exclusive. For example, the specific shape, structure, and characteristics of the exemplary embodiments may be used or implemented in another exemplary embodiment without departing from the inventive concept.

[0025] This application provides a piston-type vacuum detection valve for cryogenic gas cylinders, such as... Figure 1, 2 As shown, the piston-type vacuum detection valve 10 is integrated with the detection device 20, which includes a molecular pump 8, an ionization gauge 6, and a high-vacuum baffle valve 7. The molecular pump 8, ionization gauge 6, and high-vacuum baffle valve 7 are connected via a detection pipeline 9, and the piston-type vacuum detection valve 10 is connected to the detection pipeline 9 of the detection device 20. The piston-type vacuum detection valve 10 can also be connected to a cryogenic gas cylinder. When the vacuum insulation jacket of the cryogenic gas cylinder needs to be tested, the piston-type vacuum detection valve 10 connects the cryogenic gas cylinder and the detection pipeline 9 of the detection device 20, allowing the detection device 20 to evacuate the cryogenic gas cylinder for testing. When the test is completed, the piston-type vacuum detection valve 10 disconnects the fluid connection between the cryogenic gas cylinder and the detection pipeline 9. The piston-type vacuum detection valve 10 can adapt to frequent replacement of cryogenic gas cylinders for testing and effectively prevents air from entering the detection pipeline 9 and damaging the vacuum environment of the detection pipeline 9 and the electronic equipment in the detection device 20.

[0026] like Figure 2-4 As shown, the piston-type vacuum detection pull valve 10 includes: a valve body 1, a pull rod 2, a sealing head 3, and a sealing sleeve 4. The valve body 1 has a movable chamber 11 inside, which can accommodate the sealing head 2, the sealing sleeve 4, and at least a portion of the pull rod 2. The valve body 1 has a pull rod port 12 located at the top of the movable chamber 11, a sealing port 13 located at the bottom of the movable chamber 11, and a vacuum port 14 located on the side wall of the movable chamber 11. The pull rod port 12 is a through hole extending vertically. The sealing port 13 is configured to connect the cryogenic gas cylinder and the movable chamber 11, and the vacuum port 14 is configured to connect the detection pipeline 9 and the movable chamber 11.

[0027] The lever 2 includes a rod portion 21 that passes through the lever opening 12 and a sleeve handle 22 installed at the top end of the rod portion 21. The rod portion 21 extends in the vertical direction and can move up and down relative to the lever valve body 1 within the lever opening 12.

[0028] The sealing head 3 is coaxially mounted on the bottom end of the rod 21 and threadedly connected to the bottom end of the rod 21, thereby achieving a detachable connection with the pull rod 2. The sealing head 3 has a first position with a sealing port 13 and a second position with its bottom located above at least part of the vacuum port 14 within the movable chamber 11.

[0029] The upper surface of the plugging head 3 is provided with a threaded hole 31, and the bottom end of the rod 21 is provided with an external thread 211 that mates with the threaded hole 31. When the plugging head 3 is clamped to the gas cylinder opening of the cryogenic gas cylinder, the rod 21 rotates around its own axis, which allows the external thread 211 of the rod 21 to exit the threaded hole 31 of the plugging head 3, thereby separating the plugging head 3 from the pull rod 2.

[0030] The sleeve handle 22 is located on the upper side of the valve body 1, allowing the operator to grip it to drive the sealing head 3 between a first and second position by pulling the lever 2, and to drive the rod portion 21 to rotate around its own axis, thereby disengaging the sealing head 3 from the lever 2. The diameter of the sleeve handle 22 is larger than the diameter of the lever opening 12, which facilitates the operator's grip and operation, and prevents the lever 2 from falling out of the movable chamber 11 during downward movement. The projection of the sleeve handle 22 from top to bottom is quincunx-shaped, making it easy for the operator to grip and rotate it.

[0031] The sealing sleeve 4 is coaxially sleeved on the rod 21 and located above the plugging head 3, and can move vertically within the movable chamber 11 along with the pull rod 2. The outer surface of the sealing sleeve 4 is clearance-fitted with the side wall of the movable chamber 11. When the plugging head 3 moves from the second position to the first position, the sealing sleeve 4 seals the vacuum port 14, blocking the fluid communication between the detection pipeline 9 and the movable chamber 11, ensuring that the vacuum environment within the detection pipeline 9 is not disrupted.

[0032] A pair of positioning rings 23 are also fitted on the rod 21. The pair of positioning rings 23 are respectively arranged at the top end and the bottom end of the sealing sleeve 4, thereby restricting the position of the sealing sleeve 4 at the top and bottom, and preventing the sealing sleeve 4 from sliding up and down relative to the pull rod 2.

[0033] The diameter of the pull rod opening 12 is smaller than the diameter of the movable chamber 11, which effectively prevents the sealing sleeve 4 from moving out of the valve body 1 from the pull rod opening 12 when the pull rod 2 moves upward.

[0034] The sealing opening 13 has at least one first sealing ring groove, which is spaced apart in the vertical direction, and a first sealing ring 15 is installed in each first sealing ring groove. The sealing head 3 has at least one second sealing ring groove in its circumference, which is spaced apart in the vertical direction, and a second sealing ring 5 is installed in each second sealing ring groove. When the sealing head 3 moves to the sealing opening 13, the first sealing ring 15 and the second sealing ring 5 form a sealing structure between the sealing head 3 and the sealing opening 13, effectively blocking the airflow through the sealing opening 13.

[0035] The working principle of this application is as follows: When the sealing head 3 is in the first position, the sealing port 13 of the piston-type vacuum detection valve 10 is aligned with the cylinder opening of the cryogenic gas cylinder to be tested. By pulling up the sleeve handle 22, the entire pull rod 2, along with the sealing sleeve 4 and the sealing head 3 mounted on it, is pulled upwards until the sealing head 3 moves to the second position. At this time, the detection pipeline 9 is connected to the cryogenic gas cylinder, and the vacuum degree in the cylinder jacket is detected. After the test is completed, by pressing down the sleeve handle 22, the pull rod 2 is pushed downwards until the sealing head 3 moves to the first position, so that the sealing head 3 seals the cryogenic gas cylinder, and at the same time, the sealing sleeve 4 seals the vacuum port 14 connected to the detection pipeline 9. Then, by rotating the sleeve handle 22, the sealing head 3 is disengaged from the pull rod 2 and sealed onto the cryogenic gas cylinder. At this time, the piston-type vacuum detection valve 10 and the connected detection device 20 are removed from the cryogenic gas cylinder. After reinstalling the new sealing head 3 at the bottom of the pull rod 2, it is connected to the next cryogenic gas cylinder to be tested. There is no need to turn off the high vacuum baffle valve in the detection device 20, as well as the power supply of the molecular pump and ionization gauge. It will not damage the vacuum environment that has been evacuated in the detection pipeline 9. The detection device does not need to evacuate the vacuum every time the cryogenic gas cylinder is replaced, thus realizing rapid replacement of cryogenic gas cylinders and rapid detection.

[0036] like Figure 3 , 4 As shown, during the testing process, when the sealing head 3 is in the second position, the cryogenic gas cylinder is connected to the testing pipeline 9. At this time, the atmospheric pressure in the movable chamber 11 below the sealing head 3 is less than the atmospheric pressure outside the valve body 1, and the pull rod 2 will move downward under the pressure difference. To prevent the pull rod 2 from sliding down before the test is completed, a limiting pin 24 is also inserted radially into the rod 21. The side wall of the pull rod opening 12 is provided with a limiting groove 16 for the limiting pin 24 to move up and down and a limiting ring groove 17 for the limiting pin 24 to rotate with the rod 21. When the sealing head 3 moves to the second position, the limiting pin 24 is completely moved out of the limiting groove 16 and located on the upper side of the valve body 1. Rotating the rod 21 causes the limiting pin 24 on the rod 21 to be misaligned with the limiting groove 16. When the pull rod 2 is affected by the air pressure, the limiting pin 24 abuts against the top of the valve body 1, preventing the pull rod 2 from moving downward. After the test is completed, the rod 21 is rotated so that the limiting groove 24 is aligned with the limiting groove 16 so that it can move down with the pull rod 2. When the pull rod 2 rotates, the limiting ring groove 17 allows the limiting pin 24 to rotate freely with the rod 21.

[0037] The foregoing has shown and described the basic principles, main features, and advantages of this application. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this application. Various changes and modifications can be made without departing from the spirit and scope of this application. The scope of protection claimed by this application is defined by the appended claims, specification, and their equivalents.

Claims

1. A piston-type vacuum detection valve for cryogenic gas cylinders, connected to a detection device comprising a molecular pump, an ionization gauge, and a high-vacuum baffle valve, characterized in that, The piston-type vacuum detection valve includes: The valve body has an internal movable chamber. The valve body has a pull rod opening at the top of the movable chamber, a sealing opening at the bottom of the movable chamber, and a vacuum port on the side wall of the movable chamber. The pull rod opening is a through hole. The sealing opening connects the cryogenic gas cylinder and the movable chamber. The vacuum port connects the detection device and the movable chamber. A lever includes a rod portion passing through the lever opening and a sleeve handle installed at the top end of the rod portion. The rod portion extends in a vertical direction, and the sleeve handle is located on the upper side of the lever valve body. A sealing head, coaxially mounted to the bottom end of the rod and threadedly connected to the bottom end of the rod, has a first position within the movable chamber that seals the sealing opening and a second position where its bottom is located at least partially above the vacuum port; and A sealing sleeve is coaxially sleeved on the rod and located above the sealing head. The outer surface of the sealing sleeve is in clearance fit with the side wall of the movable chamber. The sealing sleeve is configured to seal the vacuum port when the sealing head moves from the second position to the first position.

2. The piston-type vacuum detection valve according to claim 1, characterized in that, A limiting pin is radially inserted into the rod portion, and a limiting groove for the limiting pin to move up and down and a limiting ring groove for the limiting pin to rotate around the axis of the rod portion are provided on the side wall of the pull rod opening.

3. The piston-type vacuum detection valve according to claim 1, characterized in that, The sealing opening has at least one first sealing ring groove, which is arranged at intervals along the vertical direction, and a first sealing ring is installed in each of the first sealing ring grooves.

4. The piston-type vacuum detection valve according to claim 3, characterized in that, The sealing head is provided with at least one second sealing ring groove in its circumferential direction. The at least one second sealing ring groove is arranged at intervals in the vertical direction, and a second sealing ring is installed in each of the second sealing ring grooves.

5. The piston-type vacuum detection valve according to claim 1, characterized in that, The diameter of the pull rod opening is smaller than the diameter of the movable chamber.

6. The piston-type vacuum detection valve according to claim 5, characterized in that, The diameter of the sleeve handle is larger than the diameter of the pull rod opening.

7. The piston-type vacuum detection valve according to claim 6, characterized in that, The projection of the aforementioned swivel handle from top to bottom is shaped like a plum blossom.

8. The piston-type vacuum detection valve according to claim 1, characterized in that, The rod is also fitted with a pair of positioning rings, which are respectively arranged at the top end of the sealing sleeve and the bottom end of the sealing sleeve.

9. The piston-type vacuum detection valve according to claim 1, characterized in that, The upper surface of the sealing head is provided with a threaded hole, and the bottom end of the rod is provided with an external thread that mates with the threaded hole.

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