An airtightness testing device for packaging materials

Abstract

This utility model relates to an airtightness testing device for packaging materials, which includes a fixed frame, an upper housing, a lower housing, an upper cavity, a lower cavity, and a lifting assembly. The upper housing is connected above the lower housing through the fixed frame, and the lower cavity is fixed on the lower housing. The lifting assembly is disposed on the upper housing and drives the upper cavity to move linearly in the vertical direction. The upper cavity includes a first detection plate, a first detection chamber, an inflation tube, an annular elastic airbag, a connecting flange, and a connecting pipe. The lower cavity includes a second detection plate and a second detection chamber. The lifting assembly drives the upper cavity to descend. When the first and second detection plates are in contact, the annular elastic airbag is precisely embedded in the annular groove of the second detection plate. During the expansion of the airbag, it expands outward along the inclined surface of the annular groove. The radial force generated by the expansion of the airbag acts on the edge of the film. Combined with the guiding effect of the inclined surface, the film is subjected to a uniform tensile force in the horizontal direction, achieving automatic tensioning and simultaneously providing a sealing effect.

Description

Technical Field

[0001] This utility model relates to the field of packaging material testing, and in particular to a packaging material airtightness testing device. Background Technology

[0002] In the food, pharmaceutical, and electronics industries, the air permeability of packaging film is a key indicator affecting product shelf life, safety, and performance. Food packaging needs to maintain an internal gas environment through reasonable air permeability control to prevent food oxidation, spoilage, or mold growth. Pharmaceutical packaging, on the other hand, requires precise control of air permeability to ensure drug stability and avoid drug efficacy loss due to abnormal humidity or oxygen permeation. Therefore, accurate testing of the air permeability of packaging film is an important step in ensuring product quality and reliability.

[0003] Existing testing devices have significant drawbacks in practical applications: due to the inherent flexibility and extensibility of the membrane, uneven pressure distribution or insufficient positioning accuracy of the upper and lower clamping rings during clamping and fixing can easily lead to wrinkles on the membrane surface. These wrinkles alter the actual permeation path of the gas on the membrane surface, causing turbulence in the gas flow during testing. Consequently, the test data deviates significantly from the membrane's true permeability, severely affecting the accuracy and reliability of the test results. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model provides a packaging material airtightness testing device.

[0005] The packaging material airtightness testing device provided by this utility model adopts the following technical solution:

[0006] An airtightness testing device for packaging materials includes a fixed frame, an upper housing, a lower housing, an upper cavity, a lower cavity, and a lifting assembly. The upper housing is connected above the lower housing via the fixed frame. The lower cavity is fixed to the lower housing. The lifting assembly is disposed on the upper housing and drives the upper cavity to move linearly in the vertical direction. The upper cavity includes a detection disc, a detection chamber, an inflation tube, an annular elastic airbag, a connecting flange, and a connecting pipe. The annular elastic airbag is disposed at the bottom of the detection disc, and a connecting nozzle is disposed at the top of the detection disc. The connecting nozzle is connected to the annular elastic airbag, one end of the inflation tube is connected to the connecting nozzle, and the other end of the inflation tube is connected to an external air source. The bottom of the first detection chamber is connected to the first detection plate, and the top of the first detection chamber is fixed to the lifting assembly through a connecting flange. The lower cavity includes a second detection plate and a second detection chamber. The bottom of the second detection chamber is connected to the lower housing, and the top of the second detection chamber is connected to the second detection plate. The second detection plate is provided with an annular groove, and an annular inclined surface is provided in the annular groove. The position of the annular elastic airbag corresponds to the annular groove.

[0007] Optionally, the lifting assembly includes a cylinder, a slide rod, a push plate, and a sliding sleeve. The cylinder is disposed inside the upper housing, and the output end of the cylinder is connected to the push plate. The push plate slides with the slide rod through the sliding sleeve. The two ends of the slide rod are respectively fixed to the upper housing and the lower housing, and the connecting flange is fixed to the push plate.

[0008] Optionally, the connecting pipe passes through the push plate and the upper housing, and the connecting pipe is telescopically coupled with the upper housing. An air circuit control system is provided inside the upper housing, and the connecting pipe is connected to the air circuit control system.

[0009] Optionally, the connecting pipe is provided with a multi-channel diversion chamber, specifically a honeycomb-shaped metal guide plate.

[0010] Optionally, a filter is provided on the connecting pipe, and the filter is detachably connected above the multi-channel diversion chamber.

[0011] Optionally, the outer surface of the annular elastic airbag is provided with anti-slip texture, which is uniformly distributed along the circumference of the annular elastic airbag.

[0012] Optionally, a pressure sensor is provided at the top of the first detection chamber, and the pressure sensor is connected to an external data acquisition device through a connecting pipe; a pressure sensor is provided at the bottom of the second detection chamber, and the pressure sensor is connected to an external data acquisition device through a wire.

[0013] Optionally, an air pump is installed inside the lower housing. The air pump is connected to the detection chamber 2 via an air extraction pipe, and a one-way valve is installed on the air extraction pipe.

[0014] In summary, this utility model has at least one of the following beneficial technical effects:

[0015] 1. The lifting assembly drives the upper cavity to descend. When the detection disk one and detection disk two are in contact, the annular elastic airbag is precisely embedded in the annular groove of detection disk two. During the expansion of the airbag, it expands outward along the inclined surface of the annular groove. The radial force generated by the expansion of the airbag acts on the edge of the film. Combined with the guiding effect of the inclined surface, the film is subjected to uniform tensile force in the horizontal direction, realizing automatic tensioning and simultaneously achieving a sealing effect.

[0016] 2. The microchannels of the honeycomb baffle have a rectifying effect. After the chaotic airflow enters the channel, it is forced to flow axially due to the constraint of the channel wall. The turbulence is transformed into laminar flow, and the airflow velocity and pressure tend to stabilize, which can reduce the interference of airflow eddies on the detection data.

[0017] 3. The outer surface of the annular elastic airbag is provided with anti-slip texture. The anti-slip texture is evenly distributed along the circumference of the annular elastic airbag. The anti-slip texture can increase the roughness of the contact surface between the annular elastic airbag and the film, and prevent local slippage due to insufficient friction, which can lead to uneven distribution of tension and wrinkles. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a packaging material airtightness testing device.

[0019] Figure 2 This is a schematic diagram of the upper and lower cavities.

[0020] Figure 3 This is a schematic diagram of the upper cavity (excluding the connecting tube) and the lower cavity.

[0021] Figure 4 This is a cross-sectional view of the lower cavity.

[0022] Figure 5 This is a partial sectional view of the connecting pipe.

[0023] Explanation of reference numerals in the attached drawings: 1. Fixing frame; 2. Upper housing; 3. Lower housing; 4. Upper cavity; 41. Detection disc one; 42. Detection chamber one; 43. Inflation pipe; 44. Annular elastic airbag; 45. Connecting flange; 46. Connecting pipe; 47. Connecting nozzle; 48. Anti-slip texture; 5. Lower cavity; 51. Detection disc two; 52. Detection chamber two; 53. Annular groove; 54. Annular inclined surface; 6. Lifting assembly; 61. Slide rod; 62. Push plate; 63. Sliding sleeve; 7. Honeycomb metal guide plate; 8. Filter. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0026] Furthermore, "several" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0027] This utility model discloses a device for testing the airtightness of packaging materials. (Refer to...) Figure 1A packaging material airtightness testing device includes a fixed frame 1, an upper housing 2, a lower housing 3, an upper cavity 4, a lower cavity 5, and a lifting assembly 6. The upper housing 2 is connected to the lower housing 3 via the fixed frame 1. The lower cavity 5 is fixed to the lower housing 3. The lifting assembly 6 is mounted on the upper housing 2 and drives the upper cavity 4 to move linearly in the vertical direction. The upper cavity 4 includes a detection plate 41, a detection chamber 42, an inflation tube 43, an annular elastic airbag 44, a connecting flange 45, and a connecting pipe 46. The annular elastic airbag 44 is located at the bottom of the detection plate 41. A connecting nozzle 47 is located at the top of the detection plate 41 and communicates with the annular elastic airbag 44. One end of the inflation tube 43 communicates with the connecting nozzle 47, and the other end of the inflation tube 43 is connected to an external air source. The bottom of the detection chamber 42 is connected to the detection plate 41, and the top of the detection chamber 42 is connected to the connecting flange. 45 is fixed to the lifting assembly 6. The lower cavity 5 includes a second detection plate 51 and a second detection chamber 52. The bottom of the second detection chamber 52 is connected to the lower housing 3, and the top of the second detection chamber 52 is connected to the second detection plate 51. The second detection plate 51 is provided with an annular groove 53, and an annular inclined surface 54 is provided in the annular groove 53. The annular inclined surface 54 is inclined from the inside to the outside. The position of the annular elastic airbag 44 corresponds to the annular groove 53. With this design, the lifting assembly 6 drives the upper cavity 4 to descend. When the first detection plate 41 and the second detection plate 51 are in contact, the annular elastic airbag 44 is just embedded in the annular groove 53 of the second detection plate 51. During the expansion of the airbag, it expands outward along the inclined surface of the annular groove 53. The radial force generated by the expansion of the airbag acts on the edge of the film. Combined with the guiding effect of the inclined surface, the film is subjected to uniform tensile force in the horizontal direction, realizing automatic tensioning and simultaneously achieving a sealing effect.

[0028] The lifting assembly 6 includes a cylinder, a slide rod 61, a push plate 62, and a sliding sleeve 63. The cylinder is installed inside the upper housing 2. The output end of the cylinder is connected to the push plate 62. The push plate 62 slides with the slide rod 61 through the sliding sleeve 63. The two ends of the slide rod 61 are fixed to the upper housing 2 and the lower housing 3, respectively. The connecting flange 45 is fixed on the push plate 62. The connecting pipe 46 passes through the push plate 62 and the upper housing 2. The connecting pipe 46 is telescopically connected to the upper housing 2. An air circuit control system is installed inside the upper housing 2. The connecting pipe 46 is connected to the air circuit control system. When the push plate 62 moves up and down under the action of the cylinder, it drives the connecting pipe 46 to slide back and forth on the upper housing 2. The end of the connecting pipe 46 is connected to the air circuit control system inside the upper housing 2 through a hose to realize the gas input to the detection chamber 42.

[0029] The connecting tube 46 is equipped with a multi-channel flow divider, which is specifically a honeycomb-shaped metal guide plate 7. Through this design, the micro-channels of the honeycomb-shaped guide plate have a rectifying effect. After the chaotic airflow enters the channel, it is forced to flow axially due to the constraint of the channel wall. The turbulence is transformed into laminar flow, and the airflow velocity and pressure tend to be stable, which can reduce the interference of airflow eddies on the detection data. A filter 8 is provided on the connecting tube 46. The filter 8 is detachably connected to the top of the multi-channel flow divider. By setting the filter 8, impurities can be effectively prevented from passing through the flow divider and entering the detection chamber, and impurities can be prevented from adhering to the surface of the thin film sample or the inner wall of the chamber, thus interfering with the accuracy of air permeability detection.

[0030] The outer surface of the annular elastic airbag 44 is provided with anti-slip texture 48. The anti-slip texture 48 is evenly distributed along the circumference of the annular elastic airbag 44. The anti-slip texture 48 can increase the roughness of the contact surface between the annular elastic airbag 44 and the film, and prevent insufficient friction from causing local slippage, resulting in uneven tension distribution and wrinkles.

[0031] Pressure sensor 1 is installed at the top of detection chamber 1 42, and pressure sensor 1 is connected to an external data acquisition device through connecting pipe 46; pressure sensor 2 is installed at the bottom of detection chamber 2 52, and pressure sensor 2 is connected to an external data acquisition device through wire; an air pump is installed inside the lower housing 3, and the air pump is connected to detection chamber 2 52 through an air extraction pipe, and a one-way valve is installed on the air extraction pipe.

[0032] Pressure sensor 1 at the top of detection chamber 1 42 and pressure sensor 2 at the bottom of detection chamber 2 52 are used to monitor the pressure changes inside the two chambers in real time. The pressure signals are transmitted to external data acquisition equipment through connecting pipe 46 or wires. Based on this, the pressure difference on both sides of the membrane is calculated, and the airtightness of the membrane is evaluated. The vacuum pump in the lower housing 3 evacuates detection chamber 2 52 through the vacuum pipe, so that detection chamber 2 52 forms a low-pressure environment. The one-way valve on the vacuum pipe can prevent gas backflow and ensure the stability of the low-pressure state of detection chamber 2 52, providing the basic conditions for differential pressure detection.

[0033] The aforementioned pressure sensor for monitoring pressure, vacuum pump for drawing vacuum, and one-way valve for preventing backflow are all existing conventional technologies in this field. Their specific working mechanisms are well known in the industry, so they will not be elaborated on further here.

[0034] The above are all preferred embodiments of this utility model, and are not intended to limit the scope of protection of this utility model. Therefore, all equivalent changes made to the structure, shape and principle of this utility model should be covered within the scope of protection of this utility model.

Claims

1. A package material gas tightness testing apparatus characterized by: The system includes a fixed frame (1), an upper housing (2), a lower housing (3), an upper cavity (4), a lower cavity (5), and a lifting assembly (6). The upper housing (2) is connected above the lower housing (3) via the fixed frame (1). The lower cavity (5) is fixed to the lower housing (3). The lifting assembly (6) is located on the upper housing (2) and drives the upper cavity (4) to move linearly in the vertical direction. The upper cavity (4) includes a detection disc (41), a detection chamber (42), an inflation tube (43), an annular elastic airbag (44), a connecting flange (45), and a connecting pipe (46). The annular elastic airbag (44) is located at the bottom of the detection disc (41). A connecting nozzle (47) is located at the top of the detection disc (41). The connecting nozzle (47) is connected to the annular elastic airbag. (44) Connected, one end of the inflation tube (43) is connected to the connecting nozzle (47), the other end of the inflation tube (43) is connected to an external air source, the bottom of the first detection chamber (42) is connected to the first detection plate (41), the top of the first detection chamber (42) is fixed to the lifting assembly (6) through the connecting flange (45), the lower cavity (5) includes the second detection plate (51) and the second detection chamber (52), the bottom of the second detection chamber (52) is connected to the lower housing (3), the top of the second detection chamber (52) is connected to the second detection plate (51), the second detection plate (51) is provided with an annular groove (53), the annular groove (53) is provided with an annular inclined surface (54), the annular inclined surface (54) is inclined from the inside to the outside, and the position of the annular elastic airbag (44) corresponds to the annular groove (53).

2. The packaging material airtightness testing device according to claim 1, characterized in that: The lifting assembly (6) includes a cylinder, a slide rod (61), a push plate (62), and a sliding sleeve (63). The cylinder is disposed inside the upper housing (2). The output end of the cylinder is connected to the push plate (62). The push plate (62) is slidably engaged with the slide rod (61) through the sliding sleeve (63). The two ends of the slide rod (61) are respectively fixed to the upper housing (2) and the lower housing (3). The connecting flange (45) is fixed on the push plate (62).

3. The packaging material airtightness testing device according to claim 2, characterized in that: The connecting pipe (46) passes through the push plate (62) and the upper housing (2). The connecting pipe (46) is telescopically connected with the upper housing (2). An air circuit control system is provided inside the upper housing (2). The connecting pipe (46) is connected to the air circuit control system.

4. The packaging material airtightness testing device according to claim 3, characterized in that: The connecting pipe (46) is provided with a multi-channel diversion chamber, which is specifically a honeycomb metal guide plate (7).

5. The packaging material airtightness testing device according to claim 4, characterized in that: A filter (8) is provided on the connecting pipe (46), and the filter (8) is detachably connected above the multi-channel diversion chamber.

6. The packaging material airtightness testing device according to claim 1, characterized in that: The outer surface of the annular elastic airbag (44) is provided with anti-slip texture (48), which is evenly distributed along the circumference of the annular elastic airbag (44).

7. The packaging material airtightness testing device according to claim 1, characterized in that: A pressure sensor is installed at the top of the first detection chamber (42), and the pressure sensor is connected to an external data acquisition device through a connecting pipe (46); a pressure sensor is installed at the bottom of the second detection chamber (52), and the pressure sensor is connected to an external data acquisition device through a wire.

8. The packaging material airtightness testing device according to claim 1, characterized in that: An air pump is installed inside the lower housing (3). The air pump is connected to the detection chamber (52) through an air extraction pipe. A one-way valve is installed on the air extraction pipe.

Images