Multifunctional simulation testing machine suitable for cabinet machine connection test

Abstract

The present application relates to the technical field of testing machine, disclose a multifunctional simulation testing machine suitable for cabinet machine connection test, including machine body, the cabinet cavity with rear end opening in the machine body, a plurality of wiring terminals are arranged in the cabinet cavity, the wiring terminal has input end and output end connected with the cabinet machine;The operating panel is provided with a plurality of output digital control signal or analog control signal control switch, the control switch is electrically connected with the input end, the digital control signal or analog control signal sent by the control switch is transmitted to the cabinet machine through the wiring terminal;The design that the control switch can output digital control signal or analog control signal breaks the limitation of the single function of traditional test equipment, can satisfy the diversification demand of different models, different function cabinet machine to test signal, so that a device can complete a variety of test tasks, greatly widen the applicable scene of the equipment, reduce the equipment procurement cost of enterprise;Solve the problem of single function of test device.

Description

Technical Field

[0001] This invention relates to the technical field of testing machines, and more specifically, to a multifunctional analog testing machine suitable for cabinet connection testing. Background Technology

[0002] Currently, when testing PLC cabinets on the market, it is necessary to detect signals from valves, flow meters, temperature sensors, pressure transmitters, etc., typically by testing actual equipment or individual products. This testing method has many drawbacks. The frequent wiring and searching for alternatives make the testing work extremely cumbersome, leading to low efficiency. Furthermore, using a large number of actual devices or individual products for testing results in high testing costs, which is detrimental to controlling production costs.

[0003] Therefore, there is an urgent need for a testing device that can integrate multiple signals, simplify the testing process, and reduce costs. Summary of the Invention

[0004] The purpose of this invention is to provide a multi-functional simulation test machine suitable for cabinet connection testing, aiming to solve the problem that the testing devices in the prior art have relatively limited functions.

[0005] The present invention is a multifunctional simulation test machine suitable for cabinet connection testing, comprising a body, wherein the body has a cabinet cavity with a rear opening, and the cabinet cavity is provided with a plurality of wiring terminals, wherein the wiring terminals have an input end and an output end connected to the cabinet; The machine body has a central platform that protrudes forward in the middle, and the central platform is located at the front end of the machine body; the upper part of the machine body has an inclined operation panel, and the operation panel is formed at the front end of the machine body. The operation panel is equipped with multiple control switches that output digital or analog control signals. The control switches are electrically connected to the input terminals. The digital or analog control signals emitted by the control switches are transmitted to the cabinet unit through the wiring terminals. The rear opening is provided with a cover door for opening or closing the rear opening. The cover door has multiple rear ventilation holes for ventilation and heat dissipation. The bottom of the body has a bottom plate with multiple bottom ventilation holes for ventilation and heat dissipation. The rear ventilation holes and bottom ventilation holes are respectively connected to the cabinet cavity.

[0006] Furthermore, the control switch includes a toggle switch that outputs digital control signals.

[0007] Furthermore, the control switch includes a toggle switch that outputs an analog control signal. An analog signal generator is provided in the cabinet cavity. The toggle switch is electrically connected to the analog signal generator. By toggling, the toggle switch controls the change of the analog control signal emitted by the analog signal generator.

[0008] Furthermore, the plurality of the terminals are arranged in a row to form a terminal block arranged in a strip.

[0009] Furthermore, the operation panel is equipped with a digital display that shows the magnitude of the analog control signal, and the digital display is electrically connected to the toggle switch.

[0010] Furthermore, the cover door has an outer end face facing away from the cabinet cavity, and the rear vent hole penetrates through the outer end face; a downwardly curved cylinder is provided on the outer end face, and the curved strip has a curved cavity, which penetrates through the end of the curved cylinder along the bending direction of the curved cylinder. The upper end of the curved cylinder is connected to the outer end face and surrounds the outer periphery of the rear vent hole. The lower end of the curved strip is bent downward to form a downwardly arranged lower air port, which is connected to the rear vent hole.

[0011] Furthermore, the rear vent is flat, the bending cavity is flat, and the inner wall of the bending cavity is provided with a plurality of metal springs made of metal material. Along the bending cavity from bottom to top, the metal springs are arranged inclined upwards, and the plurality of metal springs are arranged circumferentially around the bending cavity. The outer end of the metal spring is fixedly connected to the inner wall of the bending cavity, and the inner end of the metal spring extends obliquely toward the center of the bending cavity, with the inner ends of multiple metal springs spaced apart.

[0012] Furthermore, the metal spring is provided with multiple spring through holes, which extend through the metal spring from top to bottom.

[0013] Furthermore, an upper plate is provided above the bottom plate, and there is a ventilation gap between the upper plate and the bottom plate. The ventilation gap is located below the cabinet cavity, and the upper plate is provided with multiple upper ventilation holes. The ventilation interval is provided with multiple air guide tubes, each air guide tube having an air guide cavity. The upper end of the air guide tube is connected to the upper plate, and the upper end of the air guide cavity is connected to the upper ventilation hole. The lower end of the air guide tube is connected to the bottom plate, and the lower end of the air guide cavity is connected to the bottom ventilation hole. Along the height direction of the air guide tube, the air guide tube is arranged in multiple curved sections.

[0014] Furthermore, the outer periphery of the air guide cylinder is provided with multiple peripheral holes, and the air guide cavity is connected to the air permeable interval through the multiple peripheral holes.

[0015] Compared with the prior art, the multi-functional simulation test machine for cabinet connection testing provided by the present invention has achieved multiple technological breakthroughs through the optimized design of the overall structure. The cabinet cavity inside the machine provides an independent and stable installation environment for the wiring terminals, avoiding interference from the external environment to the signal transmission components and ensuring the stability of signal transmission. The central table can be used to place some test-related tools, accessories, or temporary records, making them convenient for operators to access during the test, improving operational convenience and optimizing the test process; The control panel is tilted at the front of the machine body and tilts backward from bottom to top, which conforms to the ergonomic design principle. This tilt angle makes it more comfortable for operators to operate the control switches and reduces fatigue caused by long-term operation. At the same time, the control switches are exposed on the control panel, which makes it easy for operators to quickly identify and operate them, greatly improving the convenience of operation and thus improving testing efficiency. The design of the control switch, which can output digital or analog control signals, breaks the limitation of the single function of traditional test equipment. It can meet the diverse needs of different models and functions of cabinets for test signals, enabling one device to complete multiple test tasks, greatly expanding the applicable scenarios of the equipment, reducing the equipment procurement costs for enterprises, and solving the problem of relatively single function of test devices. When the cover door is closed in the non-connected state, the rear opening can effectively prevent external dust and moisture from corroding the internal components of the cabinet, thus extending the service life of the equipment. The three-dimensional heat dissipation network formed by the rear and bottom vents can quickly dissipate the heat generated by the internal components during operation, avoiding performance degradation or damage to components due to excessive local temperature, and ensuring stable operation of the equipment during long-term high-intensity testing. Attached Figure Description

[0016] Figure 1 This is a three-dimensional schematic diagram of the body provided by the present invention; Figure 2 This is a side view sectional structural diagram of the body provided by the present invention; Figure 3 This is a schematic diagram of the arrangement structure of the wiring terminals and analog signal generator provided by the present invention; Figure 4 This is a rear view structural diagram of the machine body provided by the present invention; Figure 5 This is a partially enlarged structural schematic diagram of the sealing door and the curved cylinder provided by the present invention; Figure 6 This is a partial cross-sectional enlarged structural diagram of the organism provided by the present invention.

[0017] In the diagram: Body 10, middle platform 20, operation panel 30, cover door 40, bottom plate 50, top plate 60, ventilation interval 70, cabinet cavity 11, wiring terminal 12, analog signal generator 13, control switch 31, digital display 32, rear ventilation hole 41, outer end face 42, bending cylinder 43, bending cavity 44, lower air port 45, metal spring 46, spring through hole 47, bottom ventilation hole 51, upper ventilation hole 61, air guide cylinder 71, air guide cavity 72, outer peripheral hole 73. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0019] The implementation of the present invention will be described in detail below with reference to specific embodiments.

[0020] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this invention, it should be understood that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0021] Reference Figure 1-6 The image shown is a preferred embodiment of the present invention.

[0022] A multi-functional simulation tester suitable for cabinet connection testing includes a body 10, a cabinet cavity 11 with a rear opening in the body 10, and a plurality of wiring terminals 12 in the cabinet cavity 11, each wiring terminal 12 having an input end and an output end connected to the cabinet. The body 10 has a central platform 20 that protrudes forward in the middle and is located at the front end of the body 10; the upper part of the body 10 has an inclined operation panel 30, which is formed at the front end of the body 10. The operation panel 30 is equipped with multiple control switches 31 that output digital control signals or analog control signals. The control switches 31 are electrically connected to the input terminals. The digital control signals or analog control signals emitted by the control switches 31 are transmitted to the cabinet unit through the terminal block 12. The rear opening is provided with a cover door 40 for opening or closing the rear opening. The cover door 40 is provided with multiple rear ventilation holes 41 for ventilation and heat dissipation. The bottom of the body 10 is provided with a bottom plate 50. The bottom plate 50 is provided with multiple bottom ventilation holes 51 for ventilation and heat dissipation. The rear ventilation holes 41 and the bottom ventilation holes 51 are respectively connected to the cabinet cavity 11.

[0023] The multi-functional simulation tester for cabinet connection testing provided above has achieved multiple technological breakthroughs through the optimized design of the overall structure. The cabinet cavity 11 inside the body 10 provides an independent and stable installation environment for the wiring terminals 12, avoiding interference from the external environment to the signal transmission components and ensuring the stability of signal transmission. The central table 20 can be used to place some test-related tools, accessories or temporary records, etc., so that operators can easily access them during the test, improving the convenience of operation and optimizing the test process; The operation panel 30 is tilted at the front of the machine body 10 and tilts backward from bottom to top, which conforms to the ergonomic design principle. This tilt angle makes it more comfortable for the operator to operate the control switch 31 and reduces fatigue caused by long-term operation. At the same time, the control switch 31 is exposed on the operation panel 30, which makes it easy for the operator to quickly identify and operate, greatly improving the convenience of operation and thus improving the testing efficiency. The design of the control switch 31, which can output digital or analog control signals, breaks the limitation of the single function of traditional test equipment. It can meet the diverse needs of different models and functions of cabinets for test signals, enabling one device to complete multiple test tasks, greatly expanding the applicable scenarios of the equipment, reducing the equipment procurement costs of enterprises, and solving the problem of relatively single function of test devices. When the cover door 40 is not connected, the rear opening is closed, which can effectively prevent external dust and moisture from corroding the internal components of the cabinet cavity 11 and extend the service life of the equipment. The three-dimensional heat dissipation network formed by the rear ventilation hole 41 and the bottom ventilation hole 51 can quickly dissipate the heat generated by the internal components of the cabinet cavity 11 during operation, avoid the performance degradation or damage of components due to excessive local temperature, and ensure the stable operation of the equipment during long-term high-intensity testing.

[0024] In this embodiment, the control switch 31 includes a toggle switch that outputs a digital control signal. Thus, the toggle switch can output a stable digital control signal, which has the characteristics of strong anti-interference capability, fast transmission speed, and clear logic.

[0025] In this embodiment, the control switch 31 includes a toggle switch that outputs an analog control signal. An analog signal generator 13 is provided in the cabinet cavity 11. The toggle switch is electrically connected to the analog signal generator 13. The toggle switch controls the change of the analog control signal emitted by the analog signal generator 13 by toggling.

[0026] The toggle switch, in conjunction with the analog signal generator 13, can output continuously changing analog control signals, such as changes in physical quantities like voltage and current. This allows the testing device to simulate various analog signal environments that the cabinet may encounter in actual operation, such as changes in the output signals of analog sensors like temperature and pressure. This meets the testing requirements for the cabinet's analog input function and expands the applicability of the testing device.

[0027] Operators can easily adjust the magnitude of the analog signal by turning the switch. The operation is simple and intuitive, improving the flexibility of analog signal testing.

[0028] In this embodiment, multiple terminals 12 are arranged in rows to form a strip-shaped terminal block; this allows the numerous terminals 12 to be arranged in an orderly manner, avoiding messy tangling of the wires.

[0029] During the wiring process, operators can quickly identify and distinguish different terminals 12, reducing the possibility of wiring errors and improving wiring efficiency; at the same time, the neat terminal blocks also facilitate the later inspection, maintenance and modification of the lines, reducing the difficulty of line management.

[0030] In this embodiment, the operation panel 30 is provided with a digital display 32 that displays the magnitude of the analog control signal, and the digital display 32 is electrically connected to the toggle switch.

[0031] The digital display 32 is electrically connected to the toggle switch, which can display the specific value of the analog control signal in real time and accurately, providing an intuitive reference for the operator. The operator can precisely adjust the toggle switch according to the reading of the digital display 32 to make the analog control signal reach the required accurate value for testing, thereby improving the accuracy and controllability of analog signal testing.

[0032] In this embodiment, the cover door 40 has an outer end face 42 facing away from the cabinet cavity 11, and the rear end vent hole 41 penetrates the outer end face 42; a bending cylinder 43 is provided on the outer end face 42 and is bent downward, and the bending cylinder has a bending cavity 44. Along the bending direction of the bending cylinder 43, the bending cavity 44 penetrates the end of the bending cylinder 43. The upper end of the curved cylinder 43 is connected to the outer end face 42 and surrounds the outer periphery of the rear vent hole 41. The lower end of the curved strip is bent downward to form a downwardly arranged lower air port 45, which is connected to the rear vent hole 41.

[0033] The downward-curved cylinder 43 on the outer end face 42 of the cover door 40 is arranged around the rear vent 41, forming a downward-facing air outlet 45 at the lower end. This structural design achieves a perfect balance between heat dissipation and protection. The downward-curved shape of the cylinder 43 effectively blocks external dust, rainwater and other debris from directly entering the rear vent 41 using the principle of gravity. At the same time, its bending path can change the airflow direction, reducing the possibility of impurities carried by external airflow entering the cabinet cavity 11, thus playing a good role in dust and water protection. The connection structure between the curved cavity 44 and the rear vent 41 and the air outlet 45 ensures that the hot airflow in the cabinet cavity 11 can smoothly enter the curved cavity 44 through the rear vent 41 and then be discharged through the air outlet 45, without the presence of the protective structure hindering heat dissipation.

[0034] In addition, the curved cylinder 43 can also buffer the airflow exchange inside and outside the cabinet cavity 11, reduce the interference of strong external airflow on the stable airflow field inside the cabinet cavity 11, make the heat dissipation process more stable, and ensure the stable working environment of the internal components of the cabinet cavity 11.

[0035] In this embodiment, the rear vent 41 is flat and the bending cavity 44 is flat. The inner wall of the bending cavity 44 is provided with a plurality of metal springs 46 made of metal material. Along the bending cavity 44 from bottom to top, the metal springs 46 are arranged inclined upwards, and the plurality of metal springs 46 are arranged around the bending cavity 44 at intervals in the circumference. The outer end of the metal spring 46 is fixedly connected to the inner wall of the bending cavity 44, and the inner end of the metal spring 46 extends obliquely toward the middle of the bending cavity 44, with the inner ends of multiple metal springs 46 arranged at intervals.

[0036] The flat structure increases the cross-sectional area of ​​the vent holes and the bending cavity 44, increasing the flow of heat dissipation air and improving heat dissipation efficiency. The metal springs 46 are made of metal with excellent thermal conductivity, which can quickly absorb the heat in the bending cavity 44 and dissipate it to the outside, enhancing the heat dissipation effect. The upward tilting arrangement can effectively block falling dust and debris from entering the bending cavity 44 without affecting the upward flow of hot air. It plays a secondary protection role. Multiple metal springs 46 are arranged circumferentially at intervals. The gaps formed between their inward tilting inner ends ensure smooth airflow and can also intercept larger debris.

[0037] In addition, when airflow passes through, the metal spring 46 will vibrate slightly, which can shake off the dust attached to its surface, prevent dust from accumulating and clogging the bending cavity 44, and ensure the long-term unobstructed heat dissipation channel.

[0038] In this embodiment, the metal spring 46 is provided with multiple spring through holes 47, which pass through the metal spring 46 from top to bottom; this detailed design further improves the performance of the metal spring 46.

[0039] The through hole 47 increases the contact area between the metal spring 46 and the airflow, improving the heat dissipation efficiency of the metal spring 46 and allowing the heat in the bending cavity 44 to be dissipated more quickly through the metal spring 46. At the same time, the through hole 47 provides more flow paths for the airflow, avoiding excessive obstruction of the airflow by the metal spring 46, ensuring the flow of air in the bending cavity 44, and ensuring the efficient realization of the heat dissipation function.

[0040] In addition, the through-hole structure can reduce the weight of the metal spring 46, making it easier to vibrate under the action of airflow, enhancing the effect of shaking off dust, and further ensuring the smooth flow of the bending cavity 44.

[0041] In this embodiment, an upper plate 60 is provided above the bottom plate 50, and there is a ventilation gap 70 between the upper plate 60 and the bottom plate 50. The ventilation gap 70 is located below the cabinet cavity 11, and the upper plate 60 is provided with a plurality of upper ventilation holes 61. The ventilation interval 70 is provided with multiple air guide tubes 71, each with an air guide cavity 72. The upper end of the air guide tube 71 is connected to the upper plate 60, and the upper end of the air guide cavity 72 is connected to the upper ventilation hole 61. The lower end of the air guide tube 71 is connected to the bottom plate 50, and the lower end of the air guide cavity 72 is connected to the bottom ventilation hole 51. Along the height direction of the air guide tube 71, the air guide tube 71 is arranged in multiple curved sections.

[0042] An upper plate 60 is set above the bottom plate 50 to form a ventilation gap 70. A multi-section curved air guide tube 71 connects the upper ventilation hole 61 and the bottom ventilation hole 51. This bottom heat dissipation structure design demonstrates excellent heat dissipation and dust prevention capabilities. The ventilation gap 70 between the upper plate 60 and the bottom plate 50 provides space for heat buffering and distribution, allowing the heat in the cabinet cavity 11 to enter the ventilation gap 70 evenly through the upper ventilation hole 61.

[0043] The multi-section curved air duct 71 extends the heat dissipation path and increases the contact time between the hot airflow and the wall of the air duct 71, allowing the heat to be dissipated more fully to the outside and improving the heat dissipation efficiency. The curved structure of the air duct 71 can effectively block external dust from entering the cabinet cavity 11 through the bottom vent 51. The "maze effect" formed by the curved path can intercept most of the dust, playing a reliable dustproof role.

[0044] The complete heat dissipation channel, consisting of the upper vent 61, the air guide tube 71, and the bottom vent 51, ensures that the heat generated by the components below the cabinet cavity 11 can be dissipated in a timely manner, thus preventing the bottom components from affecting the overall performance of the equipment due to poor heat dissipation.

[0045] In this embodiment, the outer periphery of the air guide cylinder 71 is provided with multiple peripheral holes 73, and the air guide cavity 72 is connected to the air venting interval 70 through the multiple peripheral holes 73; this design further optimizes the performance of the bottom heat dissipation system.

[0046] The outer peripheral hole 73 adds an additional airflow exchange channel between the air guide cavity 72 and the venting interval 70. When the airflow in the air guide cavity 72 is obstructed due to dust accumulation or other reasons, the airflow can be diverted and supplemented between the air guide cylinder 71 and the venting interval 70 through the outer peripheral hole 73, ensuring the total amount of heat dissipation airflow and maintaining the stability of heat dissipation efficiency. At the same time, the outer peripheral hole 73 can balance the air pressure inside and outside the air guide cylinder 71, avoiding the airflow stagnation caused by excessive air pressure difference inside and outside the air guide cavity 72, making the heat dissipation process smoother.

[0047] In addition, the presence of the outer peripheral hole 73 increases the heat exchange area between the air guide tube 71 and the air vent 70, which helps to further improve the heat dissipation effect and ensure that the bottom of the equipment is always at a suitable working temperature.

[0048] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-functional simulation test machine suitable for cabinet connection testing, characterized in that, Includes a body, the body having a cabinet cavity with a rear opening, the cabinet cavity being provided with multiple wiring terminals, the wiring terminals having an input end and an output end connected to the cabinet unit; The machine body has a central platform that protrudes forward in the middle, and the central platform is located at the front end of the machine body; the upper part of the machine body has an inclined operation panel, and the operation panel is formed at the front end of the machine body; The operation panel is equipped with multiple control switches that output digital or analog control signals. The control switches are electrically connected to the input terminals. The digital or analog control signals emitted by the control switches are transmitted to the cabinet unit through the wiring terminals. The rear opening is provided with a cover door for opening or closing the rear opening. The cover door is provided with multiple rear ventilation holes for ventilation and heat dissipation. The bottom of the body is provided with a bottom plate. The bottom plate is provided with multiple bottom ventilation holes for ventilation and heat dissipation. The rear ventilation holes and the bottom ventilation holes are respectively connected to the cabinet cavity. The cover door has an outer end face facing away from the cabinet cavity, and the rear ventilation hole penetrates through the outer end face; a curved cylinder arranged downward is provided on the outer end face, the curved cylinder has a curved cavity, and the curved cavity penetrates through the end of the curved cylinder along the bending direction of the curved cylinder. The upper end of the curved cylinder is connected to the outer end face and surrounds the outer periphery of the rear vent hole. The lower end of the curved cylinder is bent downward to form a downwardly arranged lower air port, which is connected to the rear vent hole. The rear vent is flat, the bending cavity is flat, and the inner wall of the bending cavity is provided with a plurality of metal springs made of metal material. Along the bending cavity from bottom to top, the metal springs are arranged at an upward angle, and the plurality of metal springs are arranged around the bending cavity at intervals in the circumference. The outer end of the metal spring is fixedly connected to the inner wall of the bending cavity, and the inner end of the metal spring extends obliquely toward the center of the bending cavity, with the inner ends of multiple metal springs arranged at intervals.

2. The multi-functional simulation testing machine for cabinet connection testing as described in claim 1, characterized in that, The control switch includes a toggle switch that outputs digital control signals.

3. The multi-functional simulation testing machine suitable for cabinet connection testing as described in claim 1, characterized in that, The control switch includes a toggle switch that outputs an analog control signal. An analog signal generator is provided in the cabinet cavity. The toggle switch is electrically connected to the analog signal generator. By toggling, the toggle switch controls the change of the analog control signal emitted by the analog signal generator.

4. The multi-functional simulation testing machine suitable for cabinet connection testing as described in claim 1, characterized in that, The multiple terminals are arranged in a row to form a terminal block arranged in a strip.

5. The multi-functional simulation testing machine suitable for cabinet connection testing as described in claim 3, characterized in that, The operation panel is equipped with a digital display that shows the magnitude of the analog control signal, and the digital display is electrically connected to the toggle switch.

6. The multifunctional simulation testing machine for cabinet connection testing as described in any one of claims 1 to 5, characterized in that, The metal spring has multiple spring through holes, which extend through the metal spring from top to bottom.

7. The multi-functional simulation testing machine for cabinet connection testing as described in any one of claims 1 to 5, characterized in that, Above the bottom plate is an upper plate, and there is a ventilation gap between the upper plate and the bottom plate. The ventilation gap is located below the cabinet cavity, and the upper plate has multiple upper ventilation holes. The ventilation interval is provided with multiple air guide tubes, each air guide tube having an air guide cavity. The upper end of the air guide tube is connected to the upper plate, and the upper end of the air guide cavity is connected to the upper ventilation hole. The lower end of the air guide tube is connected to the bottom plate, and the lower end of the air guide cavity is connected to the bottom ventilation hole. Along the height direction of the air guide tube, the air guide tube is arranged in multiple curved sections.

8. The multi-functional simulation testing machine for cabinet connection testing as described in claim 7, characterized in that, The outer periphery of the air guide tube is provided with multiple peripheral holes, and the air guide cavity is connected to the air-permeable interval through the multiple peripheral holes.

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