Time constant determination method and apparatus, medium, product, and plethysmograph

Abstract

A time constant determination method and apparatus, a medium, a product, and a plethysmograph (1000). The method comprises: acquiring a leakage time of a leakage module at a preset opening degree, wherein the leakage time is the time required for the leakage module to release gas from a target chamber on the basis of the preset opening degree until the air pressure in the target chamber reaches a preset air pressure threshold (S101); and determining that the leakage time falls within a preset time range, and determining a time constant of the target chamber on the basis of the leakage time (S102). A leakage module with adjustable opening degree is utilized, and by acquiring the leakage time of the leakage module, automatic calibration of the time constant is achieved on the basis that the leakage time falls within the corresponding time range at the corresponding opening degree. The entire time constant calibration process eliminates the need for manual intervention, improving the efficiency and accuracy of the time constant calibration.

Description

Time constant determination method, device, medium, product and plethysmograph TECHNICAL FIELD

[0001] The present application relates to the technical field of time constant calibration, and in particular to a time constant determination method, device, medium, product and plethysmograph. BACKGROUND

[0002] The time constant represents the constant of the time process of the transition reaction, that is, the time required for a physical quantity to decay to 1 / e of the maximum value. For a quantity that decays exponentially, the time required for the amplitude to decay to 1 / e times is called the time constant.

[0003] In a pressure measuring instrument, for example, a plethysmograph, in order to maintain thermal equilibrium between the inside and outside of the instrument and avoid continuous pressure increase in the fully sealed instrument with temperature rise, a certain specification of leak hole is designed to balance the pressure inside and outside the instrument. However, since the leakage of the leak hole is greatly affected by the room temperature and the chamber pressure, before the plethysmograph test, in order to improve the test accuracy, the time constant of the leakage of the box body needs to be determined so that the time constant is within a certain range.

[0004] The current time calibration scheme mainly manually opens or closes the leak hole, which cannot guarantee that the time constant requirement can be met after one adjustment, and frequent adjustment of the position of the leak hole is required, which is time-consuming and laborious, and can easily lead to low time constant calibration efficiency and poor accuracy.

[0005] SUMMARY

[0006] The present application provides a time constant determination method, device, medium, product and plethysmograph to at least solve one of the above problems.

[0007] In a first aspect, the present application provides a time constant determination method, comprising:

[0008] acquiring a leakage time of a leakage module at a preset opening degree, the leakage time being a time when the leakage module releases the gas in a target box body based on the preset opening degree so that the gas pressure in the target box body reaches a preset gas pressure threshold;

[0009] determining that the leakage time reaches a preset time interval, and determining the time constant of the target box body based on the leakage time.

[0010] In an embodiment, the method further comprises:

[0011] determining that the leakage time does not reach the preset time interval, and adjusting the opening degree of the leakage module;

[0012] acquiring the leakage time of the leakage module at the adjusted opening degree.

[0013] In an embodiment, the adjusting the opening degree of the leakage module comprises:

[0014] If the leakage time after adjusting the opening degree of the leakage module does not reach the preset time interval, the step of adjusting the opening degree of the leakage module is repeated until the leakage time reaches the preset time interval, and the leakage time of the leakage module at the adjusted opening degree is obtained.

[0015] In an embodiment, the adjusting the opening degree of the leakage module comprises:

[0016] The adjustment coefficient for adjusting the opening degree is determined according to the leakage time at the preset opening degree;

[0017] The opening degree of the leakage module is adjusted according to the adjustment coefficient.

[0018] In an embodiment, the adjustment coefficient for adjusting the opening degree is determined according to the leakage time at the preset opening degree, comprising:

[0019] The adjustment coefficient for adjusting the opening degree is calculated and determined according to the leakage time at the preset opening degree and a predefined algorithm; wherein the predefined algorithm comprises a linear algorithm or a nonlinear algorithm;

[0020] Or,

[0021] The mapping relationship between the time interval and the adjustment coefficient is obtained, and the adjustment coefficient corresponding to the leakage time at the preset opening degree is determined according to the time interval in which the leakage time at the preset opening degree is located and the mapping relationship.

[0022] In an embodiment, the leakage module comprises one or more numbers of leakage holes; the adjusting the opening degree of the leakage module comprises:

[0023] When the number of the leakage holes is one, the opening and closing ratio of the leakage hole is determined, and the opening degree of the leakage hole is adjusted according to the opening and closing ratio;

[0024] Or,

[0025] When the number of the leakage holes is more than one, the number of the opening and closing of the leakage holes is determined, and the common opening degree of the leakage holes is adjusted according to the number of the opening and closing.

[0026] In an embodiment, the determining the time constant of the target tank based on the leakage time comprises:

[0027] The leakage time of the leakage module at the adjusted opening degree is obtained for a preset number of times;

[0028] determine a time constant of the target tank according to the leakage time obtained each time.

[0029] In an embodiment, the method further comprises:

[0030] starting a time constant determination procedure or sending information prompting to start a time constant determination procedure in response to at least one of the current time, the room temperature where the target tank is located, and the atmospheric pressure change value reaching a corresponding preset value.

[0031] In a second aspect, the present application provides a time constant determination apparatus, comprising:

[0032] an obtaining module configured to obtain a leakage time of a leakage module at a preset opening degree, the leakage time being a time when the leakage module releases a gas in a target tank based on the preset opening degree so that the gas pressure in the target tank reaches a preset gas pressure threshold;

[0033] a calibration module configured to determine that the leakage time reaches a preset time interval, and determine a time constant of the target tank based on the leakage time.

[0034] In an embodiment, the apparatus further comprises:

[0035] an adjusting module configured to determine that the leakage time does not reach the preset time interval, and adjust the opening degree of the leakage module.

[0036] The obtaining module is further configured to obtain a leakage time of the leakage module at an adjusted opening degree.

[0037] In an embodiment, the adjusting module is specifically configured to determine that the leakage time after adjusting the opening degree of the leakage module does not reach the preset time interval, repeatedly adjust the opening degree of the leakage module until the leakage time reaches the preset time interval, and obtain a leakage time of the leakage module at an adjusted opening degree.

[0038] In an embodiment, the adjusting module comprises: a determining unit configured to determine an adjusting coefficient for adjusting the opening degree according to the leakage time at the preset opening degree; and an adjusting unit configured to adjust the opening degree of the leakage module according to the adjusting coefficient.

[0039] In an embodiment, the determining unit is specifically configured to calculate and determine the adjusting coefficient for adjusting the opening degree according to the leakage time at the preset opening degree and a predefined algorithm; wherein the predefined algorithm comprises a linear algorithm or a nonlinear algorithm, or a mapping relationship between time segments and adjusting coefficients is obtained, and the adjusting coefficient corresponding to the leakage time at the preset opening degree is determined according to a time segment where the leakage time at the preset opening degree is located and the mapping relationship.

[0040] In an implementation, the leakage module comprises one or more leakage holes; and the adjusting unit is specifically configured to, when the number of the leakage holes is one, determine a ratio of opening and closing of the leakage hole, and adjust the opening degree of the leakage hole according to the ratio of opening and closing; or, when the number of the leakage holes is more than one, determine a number of the leakage holes that are opened and closed, and adjust the opening degree of the leakage holes collectively according to the number of the leakage holes that are opened and closed.

[0041] In an implementation, the calibration module is specifically configured to acquire the leakage time of the leakage module at the adjusted opening degree for a preset number of times; and determine the time constant of the target tank according to the leakage time acquired each time.

[0042] In an implementation, the device further comprises:

[0043] The response module is configured to, in response to at least one of the current time, the room temperature at which the target tank is located, and the atmospheric pressure change value reaching a corresponding preset value, start a time constant determination process or send information prompting to start the time constant determination process.

[0044] In a third aspect, the present application provides a plethysmograph comprising a tank provided with a pressurizing device and a leakage module, and a processor electrically connected to the pressurizing device and the leakage module respectively; the pressurizing device is configured to inject gas into the tank based on the control of the processor; the leakage module is configured to release the gas in the tank based on the control of the processor, so that the gas pressure in the tank reaches a preset gas pressure threshold; and the processor is configured to execute the time constant determination method provided in the first aspect.

[0045] In an implementation, the leakage module comprises a leakage hole and a control unit connected to the leakage hole.

[0046] The control unit is electrically connected to the processor and is configured to adjust the opening degree of the leakage hole based on the control of the processor.

[0047] In an implementation, the number of the leakage holes is one, and the control unit comprises a servo control device.

[0048] The servo control device is electrically connected to the processor and is configured to receive the ratio of opening and closing of the leakage module determined by the processor, and control the opening and closing size of the leakage hole according to the ratio of opening and closing, so as to adjust the opening degree of the leakage hole.

[0049] In an implementation, the number of the leakage holes is more than one, and the control unit comprises a valve for controlling each of the leakage holes.

[0050] Each of the switch valves is electrically connected to the processor, configured to receive an opening / closing signal initiated by the processor after determining the number of opening / closing, and open / close the corresponding leak hole according to the opening / closing signal to adjust the opening degree of the leak holes.

[0051] In an embodiment, the plethysmograph further comprises a pressure equalization device;

[0052] The pressure equalization device is electrically connected to the processor, configured to perform aeration treatment on the gas in the box before the pressurizing device injects gas into the inside of the box, so that the pressure in the box is equalized with the pressure outside the box.

[0053] In a fourth aspect, the present application further provides a computer readable storage medium, which stores computer execution instructions, and the computer execution instructions are used to implement the time constant determination method provided in the first aspect when executed by a processor.

[0054] In a fifth aspect, the present application further provides a computer program product, which stores a computer program, and the computer program is used to implement the time constant determination method when executed by a processor.

[0055] The time constant determination method, device, medium, product and plethysmograph provided by the present application, by obtaining the leakage time of the leakage module at a preset opening degree, the leakage time being the time when the leakage module releases the gas in the target box based on the preset opening degree, so that the gas pressure in the target box reaches a preset gas pressure threshold, determining that the leakage time reaches a preset time interval, and determining the time constant of the target box based on the leakage time. In this process, instead of the existing fixed leak hole, the leakage module with adjustable opening degree is used, and by obtaining the leakage time of the leakage module, according to the leakage time reaching the corresponding time interval, the leakage time at the corresponding opening degree is used to realize the automatic calibration of the time constant. The whole time constant calibration process does not need manual participation, effectively improving the efficiency and accuracy of the time constant calibration. BRIEF DESCRIPTION OF DRAWINGS

[0056] The accompanying drawings, which are incorporated herein and constitute part of the specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0057] FIG. 1 is a flowchart of a time constant determination method according to an embodiment of the present application;

[0058] FIG. 2 is a flowchart of another time constant determination method according to an embodiment of the present application;

[0059] FIG. 3a is one of the flowcharts of step S201 in FIG. 2;

[0060] Fig. 3b is a flowchart of step S201 in Fig. 2;

[0061] Fig. 3c is a flowchart of step S201 in Fig. 2;

[0062] Fig. 4 is a flowchart of another time constant determination method provided by the embodiment of the present application;

[0063] Fig. 5 is a structural diagram of a time constant determination device provided by the embodiment of the present application;

[0064] Fig. 6 is a structural diagram of a plethysmograph provided by the embodiment of the present application;

[0065] Fig. 7 is a structural diagram of the leakage module 120 in Fig. 6;

[0066] Fig. 8a is a structural diagram of a servo control device in the embodiment of the present application;

[0067] Fig. 8b is a structural diagram of a servo control device in the embodiment of the present application;

[0068] Fig. 8c is a structural diagram of a switch valve in the embodiment of the present application;

[0069] Fig. 9 is a structural diagram of a plethysmograph provided by the embodiment of the present application;

[0070] Fig. 10 is a flowchart of a time constant calibration process of a plethysmograph in the embodiment of the present application;

[0071] Fig. 11 is a structural diagram of an electronic device provided by the embodiment of the present application.

[0072] The above-mentioned figures have shown the specific embodiments of the present application, which will be described in more detail hereinafter. These figures and the written description are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0073] Plethysmography is the gold standard for measuring total lung capacity in clinical practice, which is based on Boyle's law. In a closed and constant temperature case, the volume change of gas is inversely proportional to the change of gas pressure. By measuring the subject's stable end-expiratory volume in a closed box (plethysmograph), the subject performs normal breathing action under occlusion, causing chest volume change, resulting in a change in the volume of the box, and a change in pressure, so that the functional residual capacity can be calculated. Functional residual capacity is the sum of the supplemental expiratory volume and residual volume, wherein the supplemental expiratory volume is the volume change from the stable end-expiratory volume to the deep end-expiratory volume, and the residual volume is the volume in the lung that does not exchange gas with the outside.

[0074] The most commonly used plethysmograph is a pressure plethysmograph, which measures the change in pressure while the volume remains constant. In order to maintain thermal balance between the inside and outside of the instrument, while avoiding the pressure in the fully sealed instrument, the continuous increase with the increase of the temperature in the instrument, the need to design a small leakage hole, so that the pressure inside and outside the instrument is balanced, while avoiding the leakage hole is too large to monitor the change of the pressure in the box.

[0075] Because the leakage amount is greatly affected by the room temperature and the room pressure, before the plethysmograph test is performed every day, in order to ensure the test accuracy, the leakage time constant of the box needs to be calibrated, so that the leakage time constant is within a certain range. The commonly used calibration method is to manually open or close the leakage hole, which requires a long time, and cannot guarantee that the adjustment can meet the requirements after one time, and the position of the leakage hole needs to be adjusted manually, which is time-consuming and laborious.

[0076] In view of the above technical problems, the embodiment of the present application provides a time constant determination method, device, medium, product and plethysmograph. The method can be applied to a plethysmograph. The leakage time of the leakage module at a preset opening degree is obtained. The leakage time is the time when the leakage module releases the gas in the target box based on the preset opening degree, so that the gas pressure in the target box reaches the preset gas pressure threshold. The leakage time is determined to reach the preset time interval, and the time constant of the target box is determined based on the leakage time. In this process, instead of the existing fixed leakage hole, a leakage module with adjustable (preset) opening degree is used, and the leakage time of the leakage module is obtained. According to the corresponding time interval reached by the leakage time, the time constant is determined based on the leakage time at the corresponding opening degree. The entire time constant calibration process does not require manual intervention, effectively improving the efficiency and accuracy of time constant calibration.

[0077] In some embodiments, in addition to being applicable to plethysmographs, the above technical solutions of the embodiment of the present application can also be applied to other devices that need to be calibrated for time constant, such as respirators, which calibrate the time constant by releasing gas through a leakage hole to ensure the accuracy of respiratory support and parameter settings; or infusion pumps, some of which can also calibrate the time constant by releasing gas through a leakage hole to ensure accurate control of infusion speed and dose; or oxygen flow meters, which usually need to calibrate the time constant by releasing gas through a leakage hole to ensure the accuracy of oxygen flow, etc. The application scenarios of the time constant calibration method are not particularly limited in the present embodiment.

[0078] In order to make the purposes, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application. The same or similar notations represent the same or similar components or components with the same or similar functions throughout the drawings. The described embodiments are part of the embodiments of the present application, rather than all the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0079] Before the embodiments of the present application are described in detail, it should be first pointed out that the user information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the embodiments of the present application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of related data need to comply with relevant laws, regulations and standards of relevant countries and regions, and provide corresponding operation portal for user to choose authorization or refusal.

[0080] FIG. 1 is a flowchart of a time constant determination method according to an embodiment of the present application, which can include the following steps S101 and S102.

[0081] In step S101, a leakage time of the leakage module at a preset opening degree is obtained. The leakage time is the time when the leakage module releases the gas in the target box based on the preset opening degree, so that the gas pressure in the target box reaches a preset gas pressure threshold.

[0082] In the present embodiment, the leakage module can be a leakage hole. By controlling the opening and closing size of the leakage hole, or controlling the number of openings and closings of multiple leakage holes, the leakage module is adjusted to the preset opening degree, or the size of the leakage hole can be controlled to adjust the leakage module to the preset opening degree. In some embodiments, the leakage module can also be other shapes or components capable of leaking gas and controlling the opening degree, and the present application does not particularly limit the specific form of the leakage module.

[0083] In the embodiment, a flow meter or a pressure sensor can be used to monitor the flow or pressure change of the gas in the target tank in real time to obtain the leakage time of the leakage module at the preset opening degree. In some embodiments, other methods can also be used to obtain the leakage time, such as using a timer, an infrared sensor (based on the heat change generated during the gas release process), etc. to obtain the leakage time of the leakage module at the preset opening degree, etc. Optionally, the target tank can be a tank of a plethysmograph, and in some embodiments, it can also be a tank of other medical devices that need to be calibrated for time constant.

[0084] In the embodiment, for the gas in the target tank (which can be a tank under a certain gas pressure condition, such as P1), the leakage module can be controlled to leak, and the leakage time can be obtained when the gas in the tank drops to a preset pressure threshold (such as P1 / 2).

[0085] It should be noted that those skilled in the art can adaptively determine the preset opening degree and the preset pressure threshold according to actual application, for example, the preset opening degree can be randomly determined, or it can be determined in combination with the current gas pressure condition in the tank (the greater the current gas pressure condition, the greater the preset opening degree can be set). Optionally, before automatic time constant calibration, a general leakage opening degree and leakage time constant can be obtained through calibration, that is, a certain amount of leakage opening degree corresponds to a certain leakage time constant. During calibration, the correspondence between the opening degree and the leakage time constant is obtained through multiple tests under a general environment, such as 21℃ and 101.3kPa. The preset pressure threshold is the same, and details are not repeated here.

[0086] In step S102, it is determined that the leakage time reaches a preset time interval, and the time constant of the target tank is determined based on the leakage time.

[0087] In the embodiment, the preset time interval can be determined according to the device that needs to determine the time constant, for example, the leakage time of the plethysmograph needs to meet the t1-t2 interval, so that the leakage time constant is within a certain range to realize the calibration of the time constant.

[0088] In the embodiment, by monitoring the leakage time of the leakage module at the corresponding opening degree, when it reaches the preset time interval, the time constant of the tank is determined according to the leakage time, for example, the leakage time can be directly determined as the time constant of the tank.

[0089] In some embodiments, to further improve the calibration accuracy of the time constant, the mean value of the multiple measured leakage times can be calculated to determine the time constant of the tank. Specifically, the step S102 of determining the time constant of the target tank based on the leakage time can include the following steps: obtaining the leakage time of the leakage module at the preset number of adjusted opening degrees; and determining the time constant of the target tank according to each obtained leakage time.

[0090] The preset number of times can be adaptively determined according to actual application and existing technology, for example, 3 times. The leakage time is obtained multiple times at the opening degree of the leakage module corresponding to the leakage time, and the mean value of the multiple measured leakage times is calculated to determine the time constant of the tank, which is more accurate than determining the time constant using a single measured leakage time.

[0091] Based on the above technical solution, the leakage module with adjustable (preset) opening degree is used instead of the existing fixed leakage hole. The leakage time of the leakage module is obtained, the time constant is determined based on the leakage time at the corresponding opening degree according to the leakage time reaching the corresponding time interval, the entire time constant calibration process does not need to be manually adjusted frequently, the time constant calibration process is automatically performed, and the efficiency and accuracy of the time constant calibration are effectively improved.

[0092] FIG. 2 is a flowchart of another time constant determination method provided by an embodiment of the present application. Based on the above embodiment, in the case where the leakage time does not reach the preset time interval, the opening degree of the leakage module is adjusted, and the leakage time at the adjusted opening degree is obtained to determine the time constant, thereby realizing automatic calibration of the time constant. Specifically, as shown in FIG. 2, in addition to the steps S101 and S102, the method provided by the embodiment can further include the following steps S201 and S202: step S201 of adjusting the opening degree of the leakage module when it is determined that the leakage time does not reach the preset time interval; and step S202 of obtaining the leakage time of the leakage module at the adjusted opening degree.

[0093] Taking the preset time interval t1-t2 as an example, when it is monitored that the leakage time does not reach the preset time interval, for example, is less than t1 or greater than t2, it indicates that the current leakage time cannot meet the time constant range of the leakage. The embodiment adjusts the opening degree of the leakage module automatically and re-obtains the leakage time at the adjusted opening degree to determine the time constant. Optionally, the automatic adjustment of the opening degree of the leakage module can be adjusted by determining the opening degree adjustment coefficient or determining the opening and closing ratio.

[0094] It can be understood that, in the embodiments of the present application, it is determined whether the leakage time reaches the preset time interval, and it is further determined that the leakage time reaches the preset time interval or the leakage time does not reach the preset time interval. In some embodiments, the determination process can be performed in other terminals or servers, and the determination result is obtained from the other terminals or servers to determine whether the leakage time reaches the preset time interval or the leakage time does not reach the preset time interval.

[0095] Next, the process of adjusting the opening degree of the leakage module in step S201 is described in detail. As shown in FIG. 3a, the step S201 of adjusting the opening degree of the leakage module can be divided into the following steps S201a and S201b:

[0096] In step S201a, it is determined that the leakage time does not reach the preset time interval, and the adjustment coefficient for adjusting the size of the opening degree is determined according to the leakage time under the preset opening degree.

[0097] In an example, a linear algorithm or a nonlinear algorithm can be used to calculate and determine the adjustment coefficient in combination with actual applications. Specifically, the adjustment coefficient for adjusting the size of the opening degree can be determined according to the leakage time under the preset opening degree in the following manner: the adjustment coefficient for adjusting the size of the opening degree is calculated and determined according to the leakage time under the preset opening degree and a predefined algorithm; wherein the predefined algorithm includes a linear algorithm or a nonlinear algorithm.

[0098] In actual applications, the relationship between the opening degree (lift) of the leakage module and the leakage time (t) may be linear or nonlinear depending on the tank, which can be fitted by the least squares method. If the relationship is linear, the relationship t=k*lift+b can be fitted to obtain the coefficients k and b; if the relationship is nonlinear, it can be exponential, polynomial, or other nonlinear forms. If it is exponential, the relationship t=k*e b*lift can be fitted; if it is polynomial, the relationship t=k1*lift n +k2*lift n-1 +…+k n *lift+b can be fitted. By obtaining the relationship between the opening degree of the leakage module and the leakage time constant, for a specific leakage time t, the corresponding leakage hole opening degree lift can be calculated according to the linear or nonlinear formula. Wherein, different opening degrees have their own corresponding adjustment coefficients, and the adjustment coefficients corresponding to different opening degrees can be determined by multiple tests of those skilled in the art. In some embodiments, the opening degree and the adjustment coefficient can be an equal ratio coefficient, i.e., the adjustment coefficient is 1 when the opening degree is 1.

[0099] In another example, the current adjustment coefficient can also be determined through a mapping relationship between the time section and the adjustment coefficient. The adjustment coefficient for adjusting the size of the opening degree can be determined according to the leakage time under the preset opening degree. The following method can also be used: obtaining a mapping relationship between the time section and the adjustment coefficient, and determining the adjustment coefficient corresponding to the leakage time under the preset opening degree according to the time section in which the leakage time under the preset opening degree is located and the mapping relationship.

[0100] In this example, the mapping relationship can be a relationship between the adjustment coefficient and the size of the opening degree that is pre-established by a person skilled in the art according to a large number of experiments. A mapping relationship table is established for different time sections and corresponding opening degrees. The adjustment coefficient mapped by the time section in which the leakage time of the current opening degree is located, that is, the adjustment coefficient to be determined, is obtained through table lookup, which is more fast and efficient.

[0101] Step S201b: adjusting the opening degree of the leakage module according to the adjustment coefficient.

[0102] In this embodiment, the relationship between the adjustment coefficient and the opening degree of the leakage module can be a positive correlation or a negative correlation, that is, the larger the adjustment coefficient, the larger the opening degree, or the larger the adjustment coefficient, the smaller the opening degree, which depends on the actual application. Through the above method of adjusting the opening degree according to the adjustment coefficient, more fine-grained opening degree adjustment can be achieved.

[0103] It can be understood that the above embodiment of adjusting the opening degree of the leakage module through the adjustment coefficient can use a (fixed) leakage hole or other scalable leakage components, and this embodiment does not particularly limit this.

[0104] In addition to the method of determining the adjustment coefficient for adjusting the opening degree of the leakage module through a constant, in other embodiments, the leakage module can include one or more numbers of leakage holes. The above step S201 of adjusting the opening degree of the leakage module can be achieved by adjusting the opening and closing ratio or the number of the leakage holes to adjust the opening degree of the leakage module.

[0105] In an example, as shown in FIG. 3b, step S201 can also be divided into step S201c: determining that the leakage time does not reach the preset time interval, determining the opening and closing ratio of the leakage hole when the number of the leakage hole is one, and adjusting the opening degree of the leakage hole according to the opening and closing ratio.

[0106] In this example, the opening degree of the leakage hole is adjusted according to the opening and closing ratio of the leakage hole, which can be realized by controlling the opening and closing ratio of the switch of the leakage hole, specifically, by controlling the opening and closing ratio of the switch, such as full opening, 1 / 2 opening, 1 / 4 opening, etc. (which can be divided according to actual application), to adjust the opening degree of the leakage hole. Among them, the specific determination of the opening and closing ratio can be determined by the person skilled in the art in combination with the actual application and the prior art, for example, if the current leakage time is greater than t2, the opening and closing ratio of the leakage hole can be reduced (such as reducing 1 / 2 opening to 1 / 3 opening), and then the leakage time is measured, and so on, until the leakage time meets the corresponding time interval.

[0107] In another example, as shown in FIG. 3c, step S201 can also be divided into step S201d: determining that the leakage time does not reach the preset time interval, determining the number of opening and closing of the leakage hole when the number of leakage holes is multiple, and adjusting the opening degree of the leakage hole according to the number of opening and closing.

[0108] In this example, the plurality of leakage holes can use leakage holes of the same size or leakage holes of different sizes. In order to improve the control efficiency of the opening degree size, leakage holes of the same size can be preferred, and the number of opening and closing of the leakage hole can be quickly determined according to the current leakage time; in some examples, in order to improve the control accuracy of the opening degree size, leakage holes of different sizes can be preferred, for example, leakage holes of large, medium and small sizes are combined, and according to the specific leakage time, the number of opening and closing of the medium-sized leakage hole and the number of opening and closing of the small-sized leakage hole are determined.

[0109] It can be understood that for the above two different examples, the total opening degree of the single leakage hole and the plurality of leakage holes (same) of the tank can be the same. In addition, the above-mentioned way of adjusting the opening degree of the leakage hole is only one or more examples provided by the present embodiment, and is not a limitation of the present application.

[0110] In some embodiments, the step of adjusting the opening degree of the leakage module in step S201 described above can be realized in the following way: determining that the leakage time after adjusting the opening degree of the leakage module does not reach the preset time interval, repeating the step of adjusting the opening degree of the leakage module until the leakage time reaches the preset time interval, and obtaining the leakage time of the leakage module at the adjusted opening degree.

[0111] Optionally, when the pressure in the tank is P1, the leakage module starts to leak at time t0, and it is determined whether the pressure in the tank decreases to P1 / 2 within the time interval t1-t2. If the time t0 is not within the interval t1-t2, the leakage opening and the leakage time are adjusted according to the relationship between the current leakage opening and the leakage time t0. If t0

[0112] Through the above-mentioned multiple adjustment of the leakage module opening, the leakage time reaches a certain time interval, thereby improving the calibration accuracy of the time constant.

[0113] FIG. 4 is a flowchart of another time constant determination method provided by an embodiment of the present application. Based on the above-mentioned embodiments, by starting the time constant calibration process or issuing a calibration prompt message under certain conditions, the automatic calibration of the time constant can be realized, thereby further improving the user experience. Specifically, in addition to the above-mentioned steps S101 and S102, the method provided by the embodiment can further include the following step S401.

[0114] Step S401: In response to at least one of the current time, the room temperature at which the target tank is located, and the atmospheric pressure change value reaching the corresponding preset value, the time constant determination process is started or a message prompting the start of the time constant determination process is issued.

[0115] As an example, a temperature sensor can be arranged in the tank (or outside the tank) to monitor whether the current time reaches the corresponding preset time. For example, the user can pre-set a certain time (which can be adaptively determined in combination with the actual application) as the timing calibration time of the time constant. Based on this timing function, the time constant calibration (or prompting the user to control the initiation of the time constant calibration) can be automatically performed before starting the detection, which can effectively shorten the calibration time of the tank and improve the calibration efficiency.

[0116] As another example, the temperature sensor can be arranged in the box (or outside the box) to monitor the temperature of the box in real time, and when the room temperature of the box reaches a corresponding temperature threshold (which can be adaptively determined according to actual application), the temperature is calibrated as a time constant. It can be understood that when the time constant calibration of the box is performed, the temperature will affect the calibration of the time constant (the pressure in the box will continue to rise with the temperature rise), and by performing the time constant calibration at a certain temperature condition (or prompting the user to control the initiation of the time constant calibration), the calibration accuracy of the time constant can be effectively improved.

[0117] As yet another example, considering that in addition to temperature, other external environment such as atmospheric pressure change value will also affect the calibration accuracy of the time constant, a barometer (an instrument for measuring atmospheric pressure, which can detect the change of atmospheric pressure and convert it into digital or graphical display) can be arranged in the box (or outside the box) to detect the atmospheric pressure change value in real time, and when the measured atmospheric pressure change value reaches a corresponding atmospheric pressure threshold, the time constant calibration is automatically started or a prompt information is sent, thereby further improving the calibration accuracy of the time constant.

[0118] In other examples, the current time, the room temperature of the target box, and the atmospheric pressure change value reaching a corresponding preset value can also be combined (or any one or more of them can be selected) to start the time constant determination process or send a prompt information to start the time constant determination process, and the principle is similar to the above examples, which will not be described here.

[0119] FIG. 5 is a structural schematic diagram of a time constant determination device provided by an embodiment of the present application. As shown in FIG. 5, the time constant determination device 50 can include an acquisition module 51 and a calibration module 52. The acquisition module 51 is configured to acquire a leakage time of the leakage module at a preset opening degree, the leakage time being a time when the leakage module releases the gas in the target box based on the preset opening degree so that the gas pressure in the target box reaches a preset gas pressure threshold. The calibration module 52 is configured to determine that the leakage time reaches a preset time interval, and determine the time constant of the target box based on the leakage time.

[0120] In some embodiments, the device further includes an adjustment module configured to determine that the leakage time does not reach the preset time interval, and adjust the opening degree of the leakage module. The acquisition module is further configured to acquire the leakage time of the leakage module at the adjusted opening degree.

[0121] In some embodiments, the adjustment module is specifically configured to determine that the leakage time does not reach the preset time interval after adjusting the opening degree of the leakage module, repeatedly adjust the opening degree of the leakage module until the leakage time reaches the preset time interval, and acquire the leakage time of the leakage module at the adjusted opening degree.

[0122] In some embodiments, the adjusting module comprises: a determining unit configured to determine an adjusting coefficient for adjusting the size of the opening degree according to the leakage time under the preset opening degree; and an adjusting unit configured to adjust the opening degree of the leakage module according to the adjusting coefficient.

[0123] In some embodiments, the determining unit is specifically configured to calculate the adjusting coefficient for adjusting the size of the opening degree according to the leakage time under the preset opening degree and a predefined algorithm; wherein the predefined algorithm comprises a linear algorithm or a nonlinear algorithm, or a mapping relationship between time segments and adjusting coefficients is obtained, and the adjusting coefficient corresponding to the leakage time under the preset opening degree is determined according to the time segment in which the leakage time under the preset opening degree is located and the mapping relationship.

[0124] In some embodiments, the leakage module comprises one or more numbers of leakage holes; and the adjusting unit is specifically configured to, when the number of the leakage holes is one, determine an opening-closing ratio of the leakage hole and adjust the opening degree of the leakage hole according to the opening-closing ratio; or when the number of the leakage holes is more than one, determine an opening-closing number of the leakage holes and adjust the common opening degree of the leakage holes according to the opening-closing number.

[0125] In some embodiments, the calibration module 52 is specifically configured to obtain the leakage time of the leakage module under the adjusted opening degree for a preset number of times; and determine the time constant of the target tank according to the leakage time obtained each time.

[0126] In some embodiments, the device further comprises a response module configured to, in response to at least one of the current time, the room temperature in which the target tank is located, and the atmospheric pressure change value reaching a corresponding preset value, start the time constant determination process or send information prompting to start the time constant determination process.

[0127] The above device provided by the embodiments of the present application can be used to execute the technical solution of the time constant determination method in the above embodiments, and has similar implementation principles and technical effects, which will not be described here again.

[0128] It should be noted that the division of each module of the above apparatus is only a logical functional division, and all or part of the modules can be integrated into one physical entity or physically separated when actually implemented. The modules can all be implemented in the form of software invoked by a processing element; all can be implemented in the form of hardware; or some modules can be implemented in the form of software invoked by a processing element, and some modules can be implemented in the form of hardware. For example, the calibration module 52 can be a separately established processing element, or can be integrated in a chip of the above apparatus, and in addition, the calibration module 52 can be stored in the form of program code in the memory of the above apparatus, and the functions of the calibration module 52 can be invoked and executed by a processing element of the above apparatus. The implementation of other modules is similar. In addition, all or part of the modules can be integrated together or independently implemented. The processing element herein can be an integrated circuit having a signal processing capability. In the implementation process, each step of the above method or each module can be completed by the integrated logic circuit of hardware or the instruction of software in the processing element.

[0129] FIG. 6 is a plethysmograph provided by an embodiment of the present application. The plethysmograph 1000 can include a box 100 provided with a pressurizing device 110 and a leakage module 120, and a processor 200 electrically connected with the pressurizing device 110 and the leakage module 120 respectively; the pressurizing device 110 is configured to inject gas into the box 100 based on the control of the processor 200; the leakage module 120 is configured to release the gas in the box 100 based on the control of the processor 200, so that the gas pressure in the box 100 reaches a preset gas pressure threshold; and the processor 200 is configured to execute the time constant determination method provided by any one of the embodiments of FIGS. 1-5.

[0130] In the present embodiment, the pressurizing device 100 pressurizes the box to make the gas in the box reach a P1 state, and at the P1 state, the leakage module 120 releases the gas to make the gas pressure in the box reach P1 / 2 (stop), and the processor 200 determines whether the leakage time corresponding to the release of the leakage module 120 satisfies the preset time interval corresponding to the time constant, and when the preset time interval is satisfied, the time constant of the plethysmograph is determined according to the leakage time.

[0131] In some embodiments, as shown in FIG. 7, the leakage module 120 includes a leakage hole 121 and a control unit 122 connected with the leakage hole 121; the control unit 122 is electrically connected with the processor 200, and is configured to adjust the opening degree of the leakage hole based on the control of the processor 200.

[0132] In some embodiments, the number of leakage holes 121 can be one, and the control unit 122 includes a servo control device, which is electrically connected with the processor 200, for receiving the opening / closing ratio of the leakage module 120 determined by the processor 200, and controlling the opening / closing size of the leakage hole 121 according to the opening / closing ratio, so as to adjust the opening degree of the leakage hole.

[0133] In this embodiment, for example, the servo control device can be as shown in FIG. 8a. The servo control device can include a servo motor 1221, a shaft coupling 1222, a screw rod 1223, a transmission block 1224, a transmission block protection device 1225, a transmission block clamping groove 1226. The processor 200 is connected with the servo motor 1221. The shaft coupling 1222 is used as a connecting device of the servo motor 1221 and the screw rod 1223. The transmission block 1224 is connected with the screw rod 1223 through the transmission block protection device 1225. The screw rod 1223 rotates to drive the transmission block 1224 to move horizontally. The transmission block 1224 is located in the transmission block clamping groove 1226. The transmission block 1224 has the protection device 1225 on both left and right sides. When the servo motor 1221 receives the control signal (adjusting the opening / closing ratio of the leakage hole) of the processor 200, the servo motor 1221 controls the movement of the transmission block 1224 based on the shaft coupling 1222 and the screw rod 1223, so that the transmission block 1224 can open or close (part of) the leakage hole according to the opening / closing ratio, thereby adjusting the opening degree of the leakage hole 121.

[0134] Further for example, the leakage hole 121 and the transmission block 1224 can be circular, as shown in FIG. 8b. In other examples, the leakage hole 121 and the transmission block 1224 can also be any other shape, wherein the leakage hole 121 and the transmission block 1224 can be the same shape or different shapes.

[0135] In some embodiments, the number of leakage holes 121 can be multiple, and the control unit 122 includes a plurality of on-off valves respectively used for controlling each leakage hole 121. Each on-off valve is electrically connected with the processor 200, for receiving the opening / closing signal initiated by the processor 200 after determining the opening / closing number, and opening / closing the corresponding leakage hole 121 according to the opening / closing signal, so as to adjust the common opening degree of the leakage holes.

[0136] In this embodiment, for example, as shown in FIG. 8c, the leakage module is composed of a plurality of small leakage holes 121 and a plurality of corresponding on-off valves 1227, which are used for respectively opening and closing the single holes in the plurality of leakage holes. The on-off valve 1227 can be an electromagnetic valve, a ball valve or any other valve that can close and open the leakage hole.

[0137] In some embodiments, in order to achieve more accurate time constant control, the servo control device can be used in combination to replace part or all of the on-off valves 1227.

[0138] It should be noted that in addition to the above on-off operation of a single or multiple leak holes, other control schemes can also be used, and any automatic on-off operation of a single or all leak holes in the multiple leak holes to change the leak time constant is within the protection scope of the embodiments of the present application.

[0139] In some embodiments, as shown in FIG. 9, the plethysmograph 1000 can further include a pressure equalization device 130; the pressure equalization device 130 is electrically connected with the processor 200, and is used to ventilate the gas in the box 100 before the pressurizing device 110 injects the gas into the inside of the box 100, so that the pressure inside the box 100 is equalized with the pressure outside the box 100.

[0140] In this embodiment, as shown in FIG. 9, the plethysmograph 1000 includes a box 100 and a processor 200, the box 100 is provided with a leak module 120, a pressurizing device 110 (which can be a pressurizing pump), and a pressure equalization device 130 (which can be a pressure equalization pump, such as a ventilation pump), wherein the pressurizing device 110 can be connected with the atmosphere and the inside of the box 100 through the first gas path blocks 140, 150, and the pressure equalization device 130 is connected with the atmosphere and the inside of the box 100 through the second gas path blocks 160, 170. When the time constant is calibrated, the pressurizing device 110 is controlled to run by the processor 200, a certain amount of gas is injected into the inside of the box 100, then the gas is leaked through the leak module 120, and the time constant is determined through the leak time calculation. Assuming that the gas injected into the box 100 by the pressurizing device 110 causes an increase of P1 pressure in the box, then the time constant can be the time required for the pressure to drop from P1 to P1 / 2.

[0141] Further, FIG. 10 shows a time constant calibration process of the plethysmograph 1000 provided by the embodiments of the present application. When the automatic time constant calibration is performed, first, a certain amount of gas is injected into the box 100 by the pressurizing device 110 to make the pressure in the box rise to P1, and then the pressurizing is stopped, and the leakage is started by the leakage module 120. It is judged whether the leakage time t0 is within t1-t2 during which the pressure in the box drops to P1 / 2. If the time t0 is not within t1-t2, the leakage opening degree and the leakage time coefficient are adjusted according to the relationship between the current leakage opening degree and the leakage time t0 (see the examples of the linear relationship or the nonlinear relationship in the above embodiments). If t0

[0142] FIG. 11 is a structural schematic diagram of an electronic device provided by the embodiments of the present application. As shown in FIG. 11, the electronic device can include a transceiver 101, a processor 102, and a memory 103.

[0143] The processor 102 executes the computer execution instructions stored in the memory, so that the processor 102 executes the schemes in the above embodiments. The processor 102 can be a general-purpose processor, including a central processing unit CPU, a network processor NP, etc.; and can also be a digital signal processor DSP, an application-specific integrated circuit ASIC, a field programmable gate array FPGA or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component.

[0144] The memory 103 is connected with the processor 102 through a system bus and completes mutual communication. The memory 103 is used for storing computer program instructions.

[0145] The transceiver 101 can be used to acquire the leakage time.

[0146] The system bus can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus or the like. The system bus can be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, only one thick line is shown in the figure, but it does not mean that there is only one bus or only one type of bus. The transceiver is used to realize the communication between the database access device and other computers (such as clients, read-write libraries and read-only libraries). The memory can include random access memory (RAM) and can also include non-volatile memory.

[0147] The embodiment of the present application also provides a computer readable storage medium, and the computer readable storage medium stores computer execution instructions. When the computer execution instructions are executed by a processor, the computer execution instructions are used to implement the time constant determination method provided in the first aspect.

[0148] It should be noted that the above storage medium provided by the embodiment of the present application can be used to execute the technical solution of the time constant determination method in the above embodiment, and the implementation principle and technical effects are similar, and will not be repeated here.

[0149] The embodiment of the present application also provides a computer program product, and the computer program product stores a computer program. When the computer program is executed by a processor, the computer program is used to implement the time constant determination method.

[0150] It should be noted that the above program product provided by the embodiment of the present application can be used to execute the technical solution of the time constant determination method in the above embodiment, and the implementation principle and technical effects are similar, and will not be repeated here.

[0151] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of the modules is only a logical function division, and actual implementation can have another division manner, for example, a plurality of modules can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed each other can be indirect coupling or communication connection through some interfaces, devices or modules, and can be electrical, mechanical or other forms.

[0152] The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical units, i.e., may be located in one place, or may be distributed to multiple network units. Part or all of the modules can be selected to implement the embodiments according to actual needs.

[0153] In addition, the functional modules in each embodiment of the present application can be integrated in one processing unit, or each module can exist physically alone, or two or more modules can be integrated in one unit. The unit formed by the above modules can be realized in the form of hardware or in the form of hardware plus software functional units.

[0154] The integrated modules realized in the form of software functional modules can be stored in a computer readable storage medium. The software functional modules stored in a storage medium include a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute part of the steps of the method of each embodiment of the present application.

[0155] It should be understood that the above processor can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor. The steps of the method disclosed in combination with the application can be directly embodied as hardware processor execution or executed by a combination of hardware and software modules in the processor.

[0156] The memory can include a high-speed RAM memory, and can also include a non-volatile storage NVM, for example at least one disk memory, and can also be a U disk, a mobile hard disk, a read-only memory, a magnetic disk or an optical disk, etc.

[0157] The above storage medium can be realized by any type of volatile or non-volatile storage device or their combination, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk or optical disk. The storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0158] An exemplary storage medium is coupled to the processor such that the processor can read information from, and can write information to, the storage medium. Of course, the storage medium can be a part of the processor. Consistent with the teachings provided herein, the processor and the storage medium can be implemented as a system-on-a-chip (SOC) where the processor and the storage medium are integrated into a single chip or as part of a system on package (SOP) where the processor and the storage medium are integrated on the same package. Alternatively, the processor and the storage medium can be implemented as discrete components in a system or host device.

[0159] Those skilled in the art can understand that all or part of the steps of the methods disclosed above can be completed by a program instructing relevant hardware. The foregoing program can be stored in a computer readable storage medium. When the program is executed, the steps of the methods disclosed above are performed. The foregoing storage medium includes various media that can store program codes, such as ROM, RAM, magnetic disk, or optical disk.

[0160] The above description is merely illustrative of the application, and the scope of the application is not limited thereto. Any changes and modifications that can be readily devised by those skilled in the art within the spirit of the application are intended to be encompassed by the scope of the application. Therefore, the scope of the application should be determined by the scope of the claims.

Claims

1. A method for determining a time constant, characterized in that: include: Obtaining a leakage time of the leakage module at a preset opening, wherein the leakage time is the time taken for the leakage module to release the gas in the target box based on the preset opening so that the air pressure in the target box reaches a preset pressure threshold; It is determined that the leakage time reaches a preset time interval, and a time constant of the target box is determined based on the leakage time.

2. The method according to claim 1, characterized in that The method further comprises: Determining that the leakage time does not reach a preset time interval, adjusting the opening of the leakage module; The leakage time of the leakage module at the adjusted opening is obtained.

3. The method according to claim 2, characterized in that The adjusting the opening of the leakage module includes: Determine that the leakage time after adjusting the opening of the leakage module does not reach the preset time interval, repeat the step of adjusting the opening of the leakage module until the leakage time reaches the preset time interval, and obtain the leakage time of the leakage module at the adjusted opening.

4. The method according to claim 2 or 3, characterized in that The adjusting the opening of the leakage module includes: determining an adjustment coefficient for adjusting the opening size according to the leakage time at the preset opening; The opening of the leakage module is adjusted according to the adjustment coefficient.

5. The method according to claim 4, characterized in that The step of determining the adjustment coefficient for adjusting the opening size according to the leakage time at the preset opening includes: Calculate and determine an adjustment coefficient for adjusting the opening size according to the leakage time under the preset opening and a predefined algorithm; wherein the predefined algorithm includes a linear algorithm or a nonlinear algorithm; or, A mapping relationship between a time segment and an adjustment coefficient is obtained, and the adjustment coefficient corresponding to the leakage time at the preset opening is determined according to the time segment in which the leakage time at the preset opening is located and the mapping relationship.

6. The method according to claim 2 or 3, characterized in that The leakage module includes one or more leakage holes; and adjusting the opening of the leakage module includes: When the number of the leakage hole is one, determining an opening and closing ratio of the leakage hole, and adjusting the opening of the leakage hole according to the opening and closing ratio; or, When there are multiple leakage holes, the number of openings and closings of the leakage holes is determined, and the common opening of the leakage holes is adjusted according to the number of openings and closings.

7. The method according to claim 2 or 3, characterized in that The determining the time constant of the target box based on the leakage time includes: Obtaining a preset number of leakage times of the leakage module at the adjusted opening; The time constant of the target box is determined according to the leakage time obtained each time.

8. The method according to any one of claims 1 to 3, characterized in that Also includes: In response to at least one of the current time, the room temperature of the target box, and the atmospheric pressure change value reaching a corresponding preset value, the time constant determination process is started or a message prompting the start of the time constant determination process is issued.

9. A time constant determination device, characterized in that: include: an acquisition module, configured to acquire a leakage time of the leakage module at a preset opening, wherein the leakage time is the time taken for the leakage module to release the gas in the target box based on the preset opening so that the air pressure in the target box reaches a preset pressure threshold; The calibration module is configured to determine whether the leakage time reaches a preset time interval and determine a time constant of the target box based on the leakage time.

10. A plethysmograph, characterized in that: It includes a box in which a pressurizing device and a leakage module are arranged, and a processor electrically connected to the pressurizing device and the leakage module respectively; The pressurizing device is configured to inject gas into the interior of the box based on control of the processor; The leakage module is configured to release the gas inside the box based on the control of the processor so that the air pressure in the box reaches a preset pressure threshold; The processor is configured to execute the time constant determination method according to any one of claims 1 to 8.

11. The plethysmograph according to claim 10, wherein The leakage module includes a leakage hole and a control unit connected to the leakage hole; The control unit is electrically connected to the processor and is used to adjust the opening of the leakage hole based on the control of the processor.

12. The plethysmograph according to claim 11, wherein The number of the leakage hole is one, and the control unit includes a servo control device; The servo control device is electrically connected to the processor, and is used to receive the opening and closing ratio of the leakage module determined by the processor, and control the opening and closing size of the leakage hole according to the opening and closing ratio to adjust the opening degree of the leakage hole.

13. The plethysmograph according to claim 11, wherein There are multiple leakage holes, and the control unit includes a switch valve for controlling each leakage hole respectively; Each of the switch valves is electrically connected to the processor, and is used to receive an opening and closing signal initiated by the processor after determining the opening and closing quantity, and open / close the corresponding leakage hole according to the opening and closing signal to adjust the common opening of the leakage holes.

14. The plethysmograph according to any one of claims 10 to 13, characterized in that Also includes a pressure equalization device; The pressure equalizing device is electrically connected to the processor and is used to ventilate the gas in the box before the pressurizing device injects gas into the box, so that the pressure inside the box is equal to the pressure outside the box.

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