A small box sealing detection device for a constant voltage environment

Abstract

The utility model provides a kind of small box sealing detection device of stable voltage environment, including test cavity, first differential pressure sensor, negative pressure balance cavity, negative pressure generating mechanism and communication valve;The test cavity includes a sealed chamber, the sealed chamber is used to place sample to be measured, the volume of the sealed chamber is greater than the volume of sample to be measured;One end of the first differential pressure sensor is communicated with the sealed chamber, the other end is communicated with atmosphere, and the first differential pressure sensor is used to perceive the pressure change of sealed chamber;The negative pressure generating mechanism is used to make the negative pressure balance cavity form negative pressure environment, and the outlet side of the negative pressure balance cavity is communicated with the sealed chamber by communication valve, and the communication valve is used for the pressure maintaining and stabilizing of negative pressure balance cavity and the communication of negative pressure balance cavity and sealed chamber.The small box sealing detection device of stable voltage environment has better voltage stabilizing capacity compared with traditional scheme, so that the accuracy of sealing detection is higher.

Description

Technical Field

[0001] This utility model relates to the field of tobacco product testing technology, specifically to a small box sealing testing device under a stable pressure environment. Background Technology

[0002] The airtightness of cigarette packs is a core element in ensuring product quality. Good airtightness can provide functions such as moisture prevention, dryness prevention, aroma lock, and odor isolation, maintain the humidity and aroma of tobacco, prevent mold or flavor loss, and ensure the taste and freshness of smoking.

[0003] In terms of storage and transportation, good sealing can block dust, microorganisms and storage pests, reducing health risks; at the same time, it meets regulatory requirements (such as preventing resale and tax supervision), preventing illegal alteration or smuggling; and it can withstand temperature and humidity changes during warehousing and transportation, extending shelf life, reducing losses, and adapting to the needs of global circulation.

[0004] In addition, well-sealed packaging symbolizes quality, reduces consumer complaints, and maintains brand reputation.

[0005] Based on the above requirements, the sealing performance of cigarette packs is one of the key performance indicators that production and research companies need to pay attention to, and a series of sealing performance testing devices have been developed for this purpose.

[0006] Currently, the methods for testing the sealing of cigarette packs in the cigarette industry include the differential pressure method, which involves placing the cigarette pack in a sealed space, drawing the space into a negative pressure, maintaining the pressure, and observing the pressure change to determine the sealing condition. The principle is reliable, but in actual application, negative pressure pumps and other equipment are used to draw the negative pressure, and the pressure holding capacity is generally limited. That is, the negative pressure may fluctuate, affecting the test results. Such fluctuations are acceptable when the requirements are not high.

[0007] However, for laboratory settings, the required precision for research is much higher than that for production in order to ensure the effectiveness of the experiment. Therefore, how to solve the problem of pressure fluctuation is a core issue that urgently needs to be addressed by those skilled in the art.

[0008] In order to solve the above problems, people have been seeking an ideal technological solution. Utility Model Content

[0009] The purpose of this invention is to address the shortcomings of existing technologies by providing a small box sealing detection device with good pressure stabilization capability and improved accuracy of sealing detection in a stable pressure environment.

[0010] To achieve the above objectives, the technical solution adopted by this utility model is: a small box sealing detection device for a stable pressure environment, comprising a test chamber, a first differential pressure sensor, a negative pressure balance chamber, a negative pressure generating mechanism, and a connecting valve; The test chamber includes a sealed chamber for placing the sample to be tested, and the volume of the sealed chamber is larger than the volume of the sample to be tested. One end of the first differential pressure sensor is connected to the sealed chamber and the other end is connected to the atmosphere. The first differential pressure sensor is used to sense the pressure change in the sealed chamber. The negative pressure generating mechanism is used to create a negative pressure environment in the negative pressure balancing chamber. The outlet side of the negative pressure balancing chamber is connected to the sealed chamber through a connecting valve. The connecting valve is used for maintaining and stabilizing the pressure in the negative pressure balancing chamber and for connecting the negative pressure balancing chamber with the sealed chamber. The air path consisting of the negative pressure balance chamber, the connecting valve, and the test chamber is equipped with a pressure relief component.

[0011] Based on the above, the connecting valve includes a valve group consisting of a first three-way valve and a second three-way valve. The three ports of the first three-way valve are respectively connected to the negative pressure balance chamber, the atmosphere, and the second three-way valve. The three ports of the second three-way valve are respectively connected to the test chamber, the atmosphere, and the first three-way valve. The first three-way valve and the second three-way valve cooperate to realize the connection between the negative pressure balance chamber and the test chamber, as well as the depressurization of the negative pressure balance chamber and the test chamber.

[0012] Based on the above, the negative pressure balancing chamber is a piston-type chamber, and the negative pressure generating mechanism is an actuator that drives the piston rod of the piston-type chamber to move.

[0013] Based on the above, the negative pressure balancing chamber is an independent buffer gas chamber structure, an on / off valve is provided on the inlet side of the negative pressure balancing chamber, the negative pressure generating mechanism is a negative pressure pump, and the negative pressure pump is connected to the inlet of the negative pressure balancing chamber through the on / off valve.

[0014] Based on the above, the negative pressure balance chamber is connected to a second differential pressure sensor, which is used to detect pressure changes in the negative pressure balance chamber.

[0015] Based on the above, the volume of the negative pressure balance chamber is greater than the volume of the sealed chamber.

[0016] Based on the above, the volume of the negative pressure balance chamber is 3-5 times the volume of the sealed chamber.

[0017] Based on the above, the end face area of ​​the negative pressure suction port of the sealed chamber is larger than the end face area of ​​the sample to be tested on the corresponding side. The end face of the negative pressure suction port of the sealed chamber is evenly distributed with air vents to prevent the sample to be tested from blocking the negative pressure suction port.

[0018] Based on the above, the test chamber includes a main body with a cavity and a top cover. A sealing ring is provided at the top of the main body corresponding to the top cover, and the top cover is pressed and closed onto the upper end of the main body by a locking mechanism.

[0019] Based on the above, the test cavity is made of a transparent material.

[0020] This invention has substantial features and advancements compared to existing technologies. Specifically, compared to traditional solutions, this invention adds a negative pressure balancing chamber and a connecting valve. First, negative pressure is drawn into the negative pressure balancing chamber. The connecting valve is used to maintain and stabilize the pressure in the negative pressure balancing chamber. After the negative pressure in the negative pressure balancing chamber stabilizes, the connecting valve is opened to connect it to the sealed chamber. The resulting negative pressure environment is more stable and will not change due to the instability of the pre-source gas. Then, a differential pressure gauge is used to observe the pressure and determine whether there is a sealing problem.

[0021] Furthermore, since the test box is a simulated cigarette pack or is a cigarette pack, and each side of the cubic structure of the cigarette pack is a plane, it is easy to adhere to the side wall of the test chamber, causing adsorption and blockage of the negative pressure suction port. Therefore, ventilation grooves are set on the corresponding side to prevent air blockage from affecting the accuracy of the test.

[0022] Furthermore, all components of the device are electrically driven, requiring minimal human intervention, which ensures the accuracy and consistency of each component's operation. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the small box sealing detection device in the stabilized environment in Embodiment 1 of this utility model.

[0024] Figure 2 This is a top view of the small box sealing detection device in the stabilized environment of Embodiment 1 of this utility model.

[0025] Figure 3 This is a schematic diagram of the test cavity in Embodiment 1 of this utility model.

[0026] Figure 4 This is a schematic diagram of the top cover in Embodiment 3 of this utility model.

[0027] Figure 5 This is a schematic diagram of the gas path of the small box sealing detection device in the stabilizing environment in Embodiment 2 of this utility model.

[0028] In the diagram: 1. Test chamber; 2. First differential pressure sensor; 3. Negative pressure balancing chamber; 4. Negative pressure generating mechanism; 5. Connecting valve; 6. Opening and closing valve; 7. Negative pressure pump; 8. Ventilation groove; 9. Second differential pressure sensor; 11. Main body; 12. Top cover; 13. Sealing ring; 14. Locking mechanism; 15. Sealed chamber; 16. Sample to be tested; 51. First three-way valve; 52. Second three-way valve. Detailed Implementation

[0029] The technical solution of this utility model will be further described in detail below through specific embodiments.

[0030] Example 1 like Figures 1-3 and Figure 5 As shown, a small box sealing detection device for a stable pressure environment includes a test chamber 1, a first differential pressure sensor 2, a negative pressure balancing chamber 3, a negative pressure generating mechanism 4, and a connecting valve 5.

[0031] In this embodiment, the test chamber 1 includes a main body 11 with a cavity and a top cover 12. A sealing ring 13 is provided at the top of the main body 11 corresponding to the top cover 12. The top cover 12 is driven by a vertically movable actuator 14 to cover the upper end of the main body 11. After the cavity of the main body 11 is sealed with the top cover 12, a sealed chamber 15 is formed. The sealed chamber 15 is used to place the sample to be tested 16. The volume of the sealed chamber 15 is larger than the volume of the sample to be tested 16 so as to provide space for the components to form a negative pressure environment.

[0032] One end of the first differential pressure sensor 2 is connected to the sealed chamber 15, and the other end is connected to the atmosphere. The first differential pressure sensor 2 is used to sense the pressure change in the sealed chamber 15 and to determine whether the cigarette pack is leaking based on the pressure change. The principle is the pressure holding method, that is, after the sealed chamber 15 is evacuated to a negative pressure environment, the pressure reaches an initial value, and after waiting for a set time, the pressure value is observed to see if it changes. If the negative pressure weakens, it indicates that the packaging of the sample under test is leaking and the internal gas enters the sealed chamber 15; if the pressure remains constant, it indicates that the packaging of the sample under test meets the sealing standard.

[0033] The negative pressure generating mechanism 4 is used to create a negative pressure environment in the negative pressure balancing chamber 3. The outlet side of the negative pressure balancing chamber 3 is connected to the sealed chamber 15 through a connecting valve 5. The connecting valve 5 is used for maintaining and stabilizing the pressure of the negative pressure balancing chamber 3, connecting the negative pressure balancing chamber 3 with the sealed chamber 15, and releasing pressure.

[0034] In this embodiment, the connecting valve 5 includes a valve group consisting of a first three-way valve 51 and a second three-way valve 52. The three ports of the first three-way valve 51 are respectively connected to the negative pressure balance chamber 3, the atmosphere, and the second three-way valve 52, and are used to control the negative pressure balance chamber to connect to the atmosphere or to the second three-way valve. The three ports of the second three-way valve 52 are respectively connected to the test chamber 1, the atmosphere, and the first three-way valve 51, and are used to control the test chamber 1 to connect to the atmosphere or to the first three-way valve. The first three-way valve and the second three-way valve cooperate to realize the connection between the negative pressure balance chamber and the test chamber, as well as the depressurization of the negative pressure balance chamber and the test chamber.

[0035] In this embodiment, the negative pressure balancing chamber 3 is a piston-type chamber, and the negative pressure generating mechanism 4 is an actuator that drives the piston rod of the piston-type chamber to move. It can be an electric actuator. After the piston rod is pulled out a certain distance, the piston rod remains stationary under the control of the actuator, and the connecting valve 5 on the outlet side is in a closed state. This allows the internal chamber of the piston-type chamber to be kept under a relatively constant negative pressure parameter. Its sealing performance depends on the sealing performance of the equipment. Generally, piston equipment used for sealing performance testing has a high sealing performance, and the negative pressure environment formed in this state is not easily changed.

[0036] In some embodiments, an on / off valve 6 is provided on the inlet side, which is used to open when the negative pressure balance chamber is emptied and close after negative pressure is drawn, thus completing the pressure holding.

[0037] At this time, since the actuator has been closed, the negative pressure environment formed will not be affected by the interference of the pre-action device and will not fluctuate. After a period of stabilization, the connecting valve 5 is opened to make the negative pressure balance chamber 3 and the sealing chamber 15 connected, and the negative pressure environment is connected to form a connected and stable negative pressure environment, which can be stabilized after the fluctuation caused by the short airflow impact.

[0038] In this embodiment, a second differential pressure sensor 9 is installed in the negative pressure balance chamber 3 to determine the negative pressure state of the negative pressure balance chamber 3.

[0039] Then, the pressure change is observed using the first differential pressure sensor 2 over a certain period of time. If the change is within the set range, it indicates that the sealing performance of the sample under test meets the standard. If the change exceeds the set range, it indicates that the sample under test is leaking.

[0040] In a preferred embodiment, in order to ensure that the negative pressure environment is sufficiently negative, the volume of the negative pressure balancing chamber can be designed to be larger than the volume of the sealed chamber, such as a 3-5 times capacity difference, so that the negative pressure can be maintained at a relatively high level. The specific parameters can be determined as needed.

[0041] In other embodiments, the piston-type cavity and actuator constitute an electric piston pump, and the aforementioned purpose is achieved by controlling the operating parameters of the electric piston pump.

[0042] In other embodiments, the test chamber is made of a transparent material, which allows for easy observation of the internal conditions.

[0043] Brief description of the work process: Open the test chamber 1, put the sample 16 to be tested into the chamber, and control the actuator 14 to drive the top cover 12 to close the chamber, forming a sealed chamber 15.

[0044] Close the two connecting valves and start the negative pressure generating mechanism 4 to evacuate the negative pressure balance chamber 3.

[0045] After the vacuum is evacuated to the set state (such as the piston rod being in its longest stretched state and the second differential pressure sensor reading being stable), the negative pressure generating mechanism 4 is turned off, causing the piston rod of the piston-type cavity to stop moving. A stable negative pressure environment is formed inside the piston-type cavity. The second differential pressure sensor 9 is observed until the pressure stabilizes and is maintained for a period of time to end the internal disturbance.

[0046] Open the two connecting valves to connect the negative pressure balance chamber 3 and the sealed chamber 15. Due to the pressure difference, the chamber pressure quickly reaches rebalancing. After a period of calm, the internal turbulence weakens or disappears. At this time, start to observe the condition of the first differential pressure sensor 2.

[0047] If the reading of the differential pressure gauge exceeds the set parameter requirements, it indicates that there is a leak. If the reading of the differential pressure gauge is within the set parameter requirements, it indicates that the sealing meets the standards.

[0048] It should be noted that, since the leaks in the test sample are usually very small, it is difficult to leak completely during the pressure rebalancing process. Therefore, the pressure rebalancing process has little interference with the detection.

[0049] After the test is completed, the gas path is switched through two connecting valves to complete the depressurization of the gas path.

[0050] Example 2 like Figure 5 As shown, the main difference between this embodiment and embodiment 1 is that the negative pressure balance chamber 3 is an independent buffer air chamber structure, the inlet side of the negative pressure balance chamber 3 is provided with an on / off valve 6, the negative pressure generating mechanism is a negative pressure pump 7, and the negative pressure pump 7 is connected to the inlet of the negative pressure balance chamber 3 through the on / off valve 6.

[0051] In this embodiment, the connection between the negative pressure balance chamber 3 and the pre-negative pressure pump 7 is isolated by the on / off valve 6, thereby ensuring that the negative pressure environment inside the negative pressure balance chamber 3 is free from external fluctuations, thus avoiding interference from the pre-amplifier.

[0052] Then, it is connected to the sealed chamber 15 through the connecting valve 5 to achieve the same purpose and effect as in Example 1.

[0053] Example 3 In this embodiment, the main difference from embodiments 1 and 2 is that the end face area of ​​the negative pressure suction port of the sealed chamber is larger than the end face area of ​​the sample to be tested on the corresponding side, and the end face of the negative pressure suction port of the sealed chamber is evenly distributed with air vents 8 to prevent the sample to be tested from blocking the negative pressure suction port.

[0054] like Figure 4 As shown, in this embodiment, the ventilation groove 8 is opened on the top cover 12, and the negative pressure suction port can be set on the top cover accordingly, thereby avoiding inaccurate measurement due to blockage.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it; although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of this utility model or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the technical solution claimed by this utility model.

Claims

1. A small box sealing detection device for a stable voltage environment, characterized in that: It includes a test chamber, a first differential pressure sensor, a negative pressure balancing chamber, a negative pressure generating mechanism, and a connecting valve; The test chamber includes a sealed chamber for placing the sample to be tested, and the volume of the sealed chamber is larger than the volume of the sample to be tested. One end of the first differential pressure sensor is connected to the sealed chamber and the other end is connected to the atmosphere. The first differential pressure sensor is used to sense the pressure change in the sealed chamber. The negative pressure generating mechanism is used to create a negative pressure environment in the negative pressure balancing chamber. The outlet side of the negative pressure balancing chamber is connected to the sealed chamber through a connecting valve. The connecting valve is used for maintaining and stabilizing the pressure in the negative pressure balancing chamber and for connecting the negative pressure balancing chamber with the sealed chamber. A pressure relief assembly is provided in the air path consisting of the negative pressure balance chamber, the connecting valve, and the test chamber.

2. The small box sealing detection device for a stable voltage environment according to claim 1, characterized in that: The connecting valve includes a valve group consisting of a first three-way valve and a second three-way valve. The three ports of the first three-way valve are respectively connected to the negative pressure balance chamber, the atmosphere, and the second three-way valve. The three ports of the second three-way valve are respectively connected to the test chamber, the atmosphere, and the first three-way valve. The first three-way valve and the second three-way valve cooperate to realize the connection between the negative pressure balance chamber and the test chamber, as well as the depressurization of the negative pressure balance chamber and the test chamber.

3. The small box sealing detection device for a stable voltage environment according to claim 1, characterized in that: The negative pressure balancing chamber is a piston-type chamber, and the negative pressure generating mechanism is an actuator that drives the piston rod of the piston chamber to move.

4. The small box sealing detection device for a stable voltage environment according to claim 1, characterized in that: The negative pressure balancing chamber is an independent buffer gas chamber structure. An on / off valve is provided on the inlet side of the negative pressure balancing chamber. The negative pressure generating mechanism is a negative pressure pump. The negative pressure pump is connected to the inlet of the negative pressure balancing chamber through the on / off valve.

5. The small box sealing detection device for a stable voltage environment according to claim 4, characterized in that: The negative pressure balance chamber is connected to a second differential pressure sensor, which is used to detect pressure changes in the negative pressure balance chamber.

6. The small box sealing detection device for a regulated environment according to claim 3, characterized in that: The volume of the negative pressure balancing chamber is greater than the volume of the sealed chamber.

7. The small box sealing detection device for a stable voltage environment according to claim 1, characterized in that: The volume of the negative pressure balancing chamber is 3-5 times the volume of the sealed chamber.

8. The small box sealing detection device for a regulated environment according to claim 1, characterized in that: The end face area of ​​the negative pressure suction port of the sealed chamber is larger than the end face area of ​​the sample to be tested on the corresponding side. The end face of the negative pressure suction port of the sealed chamber is evenly distributed with air vents to prevent the sample to be tested from blocking the negative pressure suction port.

9. The small box sealing detection device for a regulated environment according to claim 1, characterized in that: The test chamber includes a main body with a cavity and a top cover. A sealing ring is provided at the top of the main body corresponding to the top cover. The top cover is pressed and closed onto the upper end of the main body by a locking mechanism.

10. The small box sealing detection device for a regulated environment according to claim 1, characterized in that: The test chamber is made of a transparent material.

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