阅读说明：本技术 一种用于呼吸设备的加湿水箱的水温控制方法及相应装置 (Water temperature control method and corresponding device for humidification water tank of breathing equipment ) 是由 刘誉 于 2021-08-30 设计创作，主要内容包括：本发明涉及一种呼吸设备温度智能调节的方法及其相应装置,本方法旨在解决现有技术方法中呼吸设备采用固定加温档位、忽略环境温湿度对加温加湿功能的影响而不能提供一个稳定的治疗环境,呼吸设备面罩端的输出气流不能维持在最佳相对湿度等缺陷,通过实时检测呼吸设备所处环境的温湿度、呼吸设备管道气流速度、加湿水箱内水温来调节PWM驱动器占空比值,控制加热片的输出功率,从而实现呼吸设备的加热温度控制。(The invention relates to a method for intelligently adjusting the temperature of breathing equipment and a corresponding device thereof, aiming at solving the defects that the breathing equipment in the prior art adopts a fixed heating gear, the influence of the ambient temperature and humidity on the heating and humidifying functions is neglected, so that a stable treatment environment cannot be provided, the output airflow at the mask end of the breathing equipment cannot be maintained at the optimal relative humidity, and the like.)

1. A method of controlling the temperature of water in a humidification water tank for a breathing apparatus, comprising the steps of:

step 1: acquiring the ambient temperature T and the ambient absolute humidity H of the environment where the breathing equipment is located in real time at a sampling interval delta T1;

step 2: converting the environmental temperature T and the environmental absolute humidity H acquired in the step 1 to acquire the relative humidity R of the current environment;

and step 3: judging whether the relative humidity R of the environment is smaller than a preset target relative humidity or not, and if so, starting a heating function of the heating sheet; otherwise, the heating function of the heating sheet is not needed to be started;

and 4, step 4: acquiring the pipeline airflow speed L output by a respirator in real time at a time interval delta t 2;

and 5: determining a target heating temperature S according to the current environment temperature T, the environment absolute humidity H and the airflow speed L in the pipeline;

step 6: and controlling the heating time of the heating sheet by controlling the duty ratio of the PWM driver according to the detected water temperature in the humidification water tank and the target heating temperature, and further controlling the water temperature in the humidification water tank.

2. The water temperature control method according to claim 1, wherein in the step 5, the target heating temperature is determined by specifically: and the ambient temperature T, the ambient absolute humidity H and the airflow speed L in the pipeline are carried into a formula S which is 52.092-0.588T-0.125H + 0.086L, and the target heating temperature S is obtained.

3. A water temperature control method as claimed in any one of claims 1-2, wherein the PWM driver duty cycle in step 6 is determined by:

wherein C is the acquired temperature of the water in the humidification water tank, and S is the target heating temperature.

4. A water temperature control method as claimed in claim 3, wherein the temperature of water in said humidifying water tank is obtained by the following formula:

C＝-0.00006N³+0.018N²-1.985N+91.147

wherein N represents the resistance of the thermistor in close contact with the bottom of the tank.

5. A water temperature control method as claimed in any one of claims 1 to 4, wherein said sampling interval Δ t1 in step 1 is 1 minute, said preset target relative humidity in step 3 is 55%, and said time interval Δ t2 in step 4 is 100 ms.

6. A breathing apparatus employing the water temperature control method of claim 1, comprising:

the power supply module is used for supplying power to other modules of the device;

the environment temperature and humidity detection module is used for detecting the current temperature and the absolute humidity of the environment where the breathing equipment is located;

the fan driving module is used for driving a fan and controlling the breathing equipment to output airflow;

the pipeline airflow speed detection module is used for detecting the airflow speed value in the pipeline of the breathing equipment;

the target heating temperature acquisition module is used for detecting the water temperature in the humidification water tank and acquiring the target temperature of water temperature heating;

the heating module is used for adjusting the PWM duty ratio and heating the water temperature in the humidifying water tank;

and the controller module is used for controlling the environment temperature and humidity detection module, the fan driving module, the pipeline airflow speed detection module, the target heating temperature acquisition module and the heating module.

Technical Field

The invention relates to breathing machine equipment, in particular to a method for intelligently adjusting the temperature of breathing equipment and a corresponding device thereof.

Background

For auxiliary respiration products such as respiratory support equipment, the phenomenon of dry mouth and nose with different degrees mostly occurs after long-time use, and the condition of dry mouth and nose can be well improved by using a humidifier or a humidifying unit. At present, a plurality of heating gears are set for the breathing machine on the market, and the water temperature is heated to a fixed temperature to achieve the humidifying effect. The investigation and study show that the optimal air relative humidity for respiratory disease patients is 50-60%. However, the relative humidity of the air flow output from the breathing mask end is greatly affected by the air humidity in the external environment, and a fixed heating gear is set, so that a certain humidification effect can be achieved formally, and the optimal comfort level and treatment effect cannot be achieved.

The known method for keeping the water temperature of the humidifying unit constant by the respirator is to set a certain fixed duty ratio value through a PWM (Pulse-width modulation) driver to control the output power of the heating plate, and detect the water temperature according to the set sampling frequency, wherein the water temperature is obtained mainly by measuring a thermistor and converting the thermistor into the water temperature. The duty value is adjusted to 0 when the water temperature is higher than the target value, and is adjusted to a fixed value when the water temperature is lower than the target temperature. The duty ratio adjusting scheme has certain defects, and when the given duty ratio value is too large, if the temperature is heated to be close to the target temperature and needs to wait for the next sampling moment, the water temperature is possibly heated too high; given an excess of hours, the length of time to heat the water to the specified water temperature will be longer. More importantly, the influence of the external environment temperature on the heating and humidifying function effect is ignored.

Therefore, people urgently want to obtain a new method for intelligently adjusting the temperature of the breathing equipment, which can intelligently adjust the heating temperature according to the actual environment temperature and humidity, and ensure that the output airflow at the mask end is maintained at the optimal relative humidity, thereby improving the comfort level and the treatment effect of the breathing machine.

Disclosure of Invention

The invention mainly aims to provide a novel method for controlling the water temperature in a humidifying water tank in breathing equipment, and aims to overcome the defects that the breathing equipment in the prior art adopts a fixed heating gear, cannot provide a stable treatment environment due to neglect of the influence of ambient temperature and humidity on a heating and humidifying function, cannot maintain the optimal relative humidity of output airflow at a mask end of the breathing equipment and the like.

Specifically, the invention provides a control method comprising the following steps:

a method of controlling the temperature of water in a humidification water tank for a breathing apparatus, comprising the steps of:

step 1: acquiring the ambient temperature T and the ambient absolute humidity H of the environment where the breathing equipment is located in real time at a sampling interval delta T1;

step 2: converting the environmental temperature T and the environmental absolute humidity H acquired in the step 1 to acquire the relative humidity R of the current environment;

and step 3: judging whether the relative humidity R of the environment is smaller than a preset target relative humidity or not, and if so, starting a heating function of the heating sheet; otherwise, the heating function of the heating sheet is not needed to be started;

and 4, step 4: acquiring the pipeline airflow speed L output by a respirator in real time at a time interval delta t 2;

and 5: determining a target heating temperature S according to the current environment temperature T, the environment absolute humidity H and the airflow speed L in the pipeline;

step 6: and controlling the heating time of the heating sheet by controlling the duty ratio of the PWM driver according to the detected water temperature in the humidification water tank and the target heating temperature, and further controlling the water temperature in the humidification water tank.

Further, the invention also provides a breathing device applying the control method as described above:

a breathing apparatus using the water temperature control method as described above, comprising:

the power supply module is used for supplying power to other modules of the device;

the environment temperature and humidity detection module is used for detecting the current temperature and the absolute humidity of the environment where the breathing equipment is located;

the fan driving module is used for driving a fan and controlling the breathing equipment to output airflow;

the pipeline airflow speed detection module is used for detecting the airflow speed value in the pipeline of the breathing equipment;

the target heating temperature acquisition module is used for detecting the water temperature in the humidification water tank and acquiring the target temperature of water temperature heating;

the heating module is used for adjusting the PWM duty ratio and heating the water temperature in the humidifying water tank;

and the controller module is used for controlling the environment temperature and humidity detection module, the fan driving module, the pipeline airflow speed detection module, the target heating temperature acquisition module and the heating module.

The optimal relative humidity of the environment when the respiratory disease patient is promoted to recover is comprehensively considered, and the optimal water temperature heating temperature of the air flow at the mask end of the breathing machine under the optimal humidity can be obtained in real time by detecting the temperature and the humidity of the environment where the breathing equipment is located and the air flow speed of the breathing machine pipeline in real time; the duty ratio of the PWM driver is adjusted along with the detected water temperature, and the PWM duty ratio is closer to 0 when the temperature is close to the target temperature, so that the output power of the heating sheet is controlled, and the heating temperature control of the breathing equipment is realized. The scheme provided by the invention can completely avoid the situation of overhigh temperature, and can ensure that the output airflow at the mask end of the breathing equipment can be maintained at the optimal relative humidity, such as about 55 percent.

Drawings

Fig. 1 is a flow chart of a method for intelligently adjusting the temperature of a breathing apparatus according to the present invention;

FIG. 2 is a schematic diagram of the heating of a humidification water tank of a breathing apparatus according to the present invention;

FIG. 3 is a schematic diagram of the breathing apparatus PWM driver duty cycle setting according to the present invention;

FIG. 4 is a functional block diagram of the intelligent temperature regulating device of the breathing equipment according to the invention;

description of the drawings: 1-heating water tank, 2-heating plate.

Detailed Description

It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

For components or elements known in the art, which may have different names without affecting the scope of the present invention, for example, a humidifying water tank may also be referred to as a "humidifying tank" or a "heating water tank" or the like.

As shown in fig. 1, the present invention provides a method for intelligently adjusting the temperature of a breathing apparatus, comprising the following steps:

step 1: the temperature and the absolute humidity of the environment where the breathing equipment is located are acquired in real time at a sampling interval delta t1, and in order to improve the control effect, the sampling time interval is preferably 1 min.

As is known, there are various methods for acquiring the ambient temperature and the absolute humidity, such as a temperature sensor and an absolute humidity sensor, and the specific embodiments are not intended to limit the present invention.

Step 2: and converting the acquired absolute humidity into relative humidity.

Typically, the absolute humidity at the collected ambient temperature can be obtained by looking up a saturation humidity table at each temperature, and the relative humidity is absolute humidity/saturation humidity.

And step 3: judging whether the relative humidity of the environment is smaller than a preset target relative humidity (preferably 55%), and if so, starting a heating function of the heating plate; otherwise, the heating function of the heating plate is not started.

And 4, step 4: acquiring the air flow speed of a pipeline output by a fan of the respirator in real time at a time interval delta t 2; preferably, the sampling time interval is 100ms, and the airflow speed in the pipeline is mainly acquired by collecting data of the flow sensor.

And 5: acquiring a target heating temperature which can ensure that the airflow at the air outlet end of the breathing mask reaches a target relative humidity according to the current environment temperature, the environment absolute humidity and the airflow speed in the pipeline;

in the step 5, the target heating temperature obtaining method includes that the detected current environment temperature T, the absolute humidity H of the current environment, and the airflow speed L in the pipeline under the driving of the fan are substituted into an empirical formula S of 52.092-0.588T-0.125H + 0.086L, and the target heating temperature S of the water temperature in the humidification water tank is obtained. When the temperature of the water in the humidifying water tank is controlled to be S, the output airflow of the breathing mask end can be controlled to be maintained at about 55% of relative humidity when the device is used in the corresponding environment.

For example, when the ambient temperature T is 30 degrees Celsius, the absolute humidity is 0.01977Kg/m³When the airflow speed is 40L/min, the target heating temperature S is 37.8 ℃ through calculation of the formula.

Step 6: detecting the water temperature in the humidifying water tank, controlling the duty ratio of the PWM driver to control the heating temperature according to the detected water temperature in the humidifying water tank and the target heating temperature obtained in the step 5, wherein the setting of the duty ratio of the PWM driver meets the following conditions:

wherein C is the acquired temperature of the water in the humidification water tank, and S is the target heating temperature.

The heating principle of the humidifying water tank of the breathing machine is shown in figure 2, the heating sheet is attached to the bottom of the humidifying water tank, and the temperature is transferred into the humidifying water tank through the heat conduction steel plate at the bottom. The resistance of the thermistor in the heater chip is collected in real time, and the temperature of the heater chip can be easily obtained (for example, by referring to an rt (temperature resistor) table). The heating plate is tightly attached to the bottom of the water tank, and the temperature of the heating plate is close to the water temperature.

Further, the more accurate water temperature C can be obtained by the thermistor value conversion through the following formula.

C＝-0.00006N³+0.018N²-1.985N+91.147

Where N represents the resistance of the thermistor in the heat patch.

It will be appreciated by those skilled in the art that the above conversion equation is not necessary, and that other means may be used to correct for the difference between the heater chip temperature and the water temperature.

Further, for precise temperature control, the sampling time interval of the thermistor is preferably a sampling time interval of the gas flow rate.

The PWM driver adjusts the duty ratio value and can control the on-time of the heating sheet circuit, the larger the duty ratio is, the longer the on-time of the heating sheet circuit is, the higher the output power of the heating sheet is, and the faster the water temperature rises. As shown in fig. 3, when it is detected that the water temperature is less than or equal to S-10, the PWM duty (%) is set to be constant 100; when the water temperature is detected to be higher than S-10 and lower than S, the PWM duty ratio (%) is set to be (S-C)/0.1, and the PWM duty ratio value is linearly reduced along with the continuous heating; when the detected water temperature is equal to or greater than S, the PWM duty is set to 0. When the water temperature is low, the higher PWM duty ratio value is set to enable the water temperature to rise rapidly, and when the water temperature is high, the lower PWM duty ratio value is set to ensure that the water temperature can be stably controlled to be close to S.

Accordingly, in order to achieve the above object, the present invention further provides an apparatus for intelligently adjusting the temperature of a breathing apparatus, as shown in fig. 4, the apparatus comprising:

the power supply module is used for supplying power to other modules of the device;

the environment temperature and humidity detection module is used for detecting the current temperature and the absolute humidity of the environment where the breathing equipment is located;

the fan driving module is used for driving a fan and controlling the breathing equipment to output airflow;

the pipeline airflow speed detection module is used for detecting the airflow speed value in the pipeline of the breathing equipment;

the target heating temperature acquisition module is used for detecting the water temperature in the humidification water tank and acquiring the target temperature of water temperature heating;

the heating module is used for adjusting the PWM duty ratio and heating the water temperature in the humidifying water tank;

and the controller module is used for controlling the environment temperature and humidity detection module, the fan driving module, the pipeline air flow speed detection module, the target heating temperature acquisition module and the heating module.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.