CN110749037A

CN110749037A - Automatic cleaning method and device for evaporator of air conditioner

Info

Publication number: CN110749037A
Application number: CN201810816869.1A
Authority: CN
Inventors: 李川; 廖小青; 汤建; 纪翔
Original assignee: Daikin Industries Ltd
Current assignee: Daikin Industries Ltd
Priority date: 2018-07-23
Filing date: 2018-07-23
Publication date: 2020-02-04
Anticipated expiration: 2038-07-23
Also published as: CN110749037B; JP2020016429A; JP6881505B2

Abstract

The invention relates to an automatic cleaning method and device for an evaporator of an air conditioner. The method comprises the following steps: frosting the surface of the evaporator; determining a target temperature of the evaporator; continuously detecting the detection temperature of the evaporator; calculating a rate of decrease of the detected temperature; judging whether the detected temperature reaches the target temperature or not, and judging whether the reduction rate of the detected temperature reaches a preset condition so as to judge whether frosting is finished or not; when it is judged that the frosting is completed, defrosting is performed to clean the evaporator.

Description

Automatic cleaning method and device for evaporator of air conditioner

Technical Field

The invention relates to the field of air conditioners, in particular to a method and a device for cleaning an evaporator of an air conditioner.

Background

Air conditioners tend to accumulate a significant amount of dust on components, such as the evaporator, during use. If the dust is not cleaned in time, the heat exchange performance of the evaporator is greatly reduced, and bacteria are easy to breed and mildew is easy to form.

Conventionally, cleaning of an air conditioner relies on manual cleaning by a user or a maintenance person, which requires a great deal of effort.

There has been proposed an automatic cleaning method of an evaporator of an air conditioner by frosting the evaporator of the air conditioner and then cleaning the surface of the evaporator using condensed water generated after the frost is melted. This automatic cleaning method also has room for optimization in cleaning effect and energy consumption.

Disclosure of Invention

The invention aims to provide an automatic cleaning method and device for an evaporator of an air conditioner, which can ensure the cleaning effect and reduce the energy consumption of automatic cleaning by more accurately judging the time point of frost formation completion.

The invention adopts the technical scheme that the automatic cleaning method of the evaporator of the air conditioner comprises the following steps: frosting the surface of the evaporator; determining a target temperature of the evaporator; continuously detecting the detection temperature of the evaporator; calculating a rate of decrease of the detected temperature; judging whether the detected temperature reaches the target temperature or not, and judging whether the reduction rate of the detected temperature reaches a preset condition so as to judge whether frosting is finished or not; when it is judged that the frosting is completed, defrosting is performed to clean the evaporator.

According to one aspect of the invention, a method of determining a target temperature of the evaporator comprises: and calculating the target temperature according to the indoor temperature and the indoor humidity of the evaporator.

According to an aspect of the present invention, the determining that the rate of decrease of the detected temperature reaches a preset condition when the detected temperature reaches the target temperature includes: a. accumulating the increasing times when the decreasing rate of the detection temperature of the evaporator is increased; b. judging whether the increasing times reaches a first threshold value, if so, entering the step c, otherwise, returning to the step a; c. and judging that frosting is finished.

According to an aspect of the present invention, the step of judging that the falling rate of the detected temperature reaches a preset condition when it is judged that the falling rate of the detected temperature of the evaporator is not increased in step a when the detected temperature reaches the target temperature further comprises: d. accumulating the time of decreasing or not changing when the decreasing rate of the detected temperature of the evaporator is decreased or not changed; e. and d, judging whether the time reduced or unchanged reaches a second threshold value, if so, entering the step c, and otherwise, returning to the step d.

According to an aspect of the present invention, when the detected temperature does not reach the target temperature and the frosting time reaches a third threshold, it is judged that frosting is completed.

According to an aspect of the present invention, a surface of the evaporator is frosted in a cooling mode or a frosting mode of the air conditioner, wherein an inner fan of the air conditioner is operated at a lowest wind level in the frosting mode.

According to one aspect of the present invention, a method of defrosting includes placing the air conditioner in a ventilation mode.

According to an aspect of the present invention, the rotation speed of the inner fan of the air conditioner in the ventilation mode is increased as the room temperature is increased.

According to one aspect of the present invention, the method further comprises continuously detecting whether the ventilation time reaches a preset time in the ventilation mode, and if so, enabling the air conditioner to finish the cleaning operation; otherwise, the air conditioner is enabled to continue ventilation operation.

According to an aspect of the present invention, the air conditioner includes a blade assembly, and the air guide blade of the blade assembly swings downward at a predetermined angle with respect to a horizontal plane when frost is formed and/or defrosted.

Another aspect of the present invention provides an automatic cleaning apparatus for an evaporator of an air conditioner, including an evaporator, an inner fan, and a controller, wherein the controller controls the operation of the evaporator and the inner fan according to the above method.

In another aspect, the present invention provides an air conditioner including an indoor unit including the automatic cleaning apparatus as described above, and a blade assembly whose air guide blade swings downward at a predetermined angle with respect to a horizontal plane.

Due to the adoption of the technical scheme, compared with the prior art, the invention can more accurately judge the time point of frost formation completion, thereby ensuring that a proper amount of condensed water is used for cleaning the surface of the evaporator and ensuring the cleaning effect. In addition, the time point of frost formation completion is accurately judged, so that unnecessary energy consumption caused by continuous meaningless work of the evaporator after the frost formation is completed can be avoided, and the energy consumption of automatic cleaning is reduced.

Drawings

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below, wherein:

fig. 1 is a block diagram of an automatic cleaning apparatus for an evaporator of an air conditioner according to an embodiment of the present invention.

Fig. 2 is a flowchart illustrating an automatic cleaning method for an evaporator of an air conditioner according to an embodiment of the present invention.

Fig. 3 is a flowchart illustrating a frosting preset condition determining process of an air conditioner according to an embodiment of the present invention.

Fig. 4 is a flowchart illustrating a determination of a frosting completion time point of an air conditioner according to an embodiment of the present invention.

Fig. 5 is a sectional view of an indoor unit of an air conditioner according to an embodiment of the present invention.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described herein, and thus the present invention is not limited to the specific embodiments disclosed below.

As used in this application and the appended claims, the terms "a," "an," and/or "the" are not intended to be inclusive in the singular, but rather are intended to be inclusive in the plural unless the context clearly dictates otherwise. In general, the terms "comprises" and "comprising" merely indicate that steps and elements are included which are explicitly identified, that the steps and elements do not form an exclusive list, and that a method or apparatus may include other steps or elements.

Embodiments of the present invention describe an automatic cleaning method and apparatus of an evaporator of an air conditioner, which can ensure a cleaning effect and reduce energy consumption for automatic cleaning.

Fig. 1 is a block diagram of an automatic cleaning apparatus for an evaporator of an air conditioner according to an embodiment of the present invention. Referring to fig. 1, the apparatus 100 may include an evaporator 110, an inner fan 120, a temperature sensor 130, and a controller 140. Components of the air conditioner not relevant to the present invention are not shown in order to avoid obscuring the focus of the present invention. The evaporator 110, the inner fan 120, and the temperature sensor 130 are all electrically connected to the controller 140. The temperature sensor 130 is provided on the evaporator 110 to detect the temperature of the evaporator 110. The temperature sensor 130 is preferably disposed at a position on the surface of the evaporator 110. The controller 140 may control operations of the evaporator 110, the inner fan 120, and the temperature sensor 130. The automatic washing device may further have an indoor temperature sensor 150 and an indoor humidity sensor 160 for sensing indoor temperature and humidity, respectively, and transmitting them to the controller 140.

Fig. 2 is a flowchart illustrating an automatic cleaning method for an evaporator of an air conditioner according to an embodiment of the present invention. This method may be implemented in the automatic cleaning device 100 shown in fig. 1 or a variation thereof. Referring to fig. 2, the method of the present embodiment includes:

in step 201, the surface of the evaporator is frosted.

In this step, the surface of the evaporator is frosted in a cooling mode of the air conditioner. Additionally or alternatively, the air conditioner may also have a dedicated frosting mode in which the surface of the evaporator is frosted. In the frosting mode, the inner fan of the air conditioner can be operated at the lowest wind level. Referring to fig. 1, the controller 140 may frost a surface of the evaporator 110 in a cooling mode or a frosting mode. The controller 140 may coordinate the wind speed of the inner fan 120 when needed.

In step 202, a target temperature for the evaporator is determined.

In this step, a target temperature of the corresponding evaporator may be determined according to the current environment. This target temperature is a temperature for judging whether or not frosting is completed. The target temperature of the evaporator can be calculated from the indoor temperature and the indoor humidity of the environment in which the air conditioner is located. Referring to fig. 1, the controller 140 may obtain an indoor temperature and an indoor humidity from an indoor temperature sensor 150 and an indoor humidity sensor 160, and calculate a target temperature of the evaporator based thereon. In an alternative embodiment, the indoor humidity sensor 160 may not be provided, but instead an approximation calculation may be performed at a fixed indoor humidity (e.g., RH 60%).

In step 203, the detected temperature of the evaporator is continuously detected.

This step can be performed during the frosting process to know the temperature of the evaporator surface. Referring to fig. 1, the temperature sensor 130 may continuously detect the detected temperature of the evaporator surface and transmit it to the controller 140.

In step 204, the rate of decrease of the detected temperature is calculated.

This step can be performed during the frosting process to know the rate of drop of the detected temperature. Detecting the change in the rate of temperature decrease is an important indicator for determining whether or not frosting is complete. Referring to fig. 1, the controller 140 may calculate a rate of decrease of the detected temperature using the series of detected temperatures obtained in step 203.

In step 205, it is determined whether the detected temperature reaches the target temperature and the rate of decrease of the detected temperature reaches a preset condition, thereby determining whether the frosting is completed.

This step may be performed during the frosting process to determine if frosting is complete. On the one hand, whether the detected temperature reaches the target temperature can be known through comparison. Whether the detected temperature reaches the target temperature is an important index for judging whether frosting is finished. Referring to fig. 1, the controller 140 may make this comparison using the series of detected temperatures obtained in step 203 and the target temperature determined in step 202.

The detected temperature reaches the target temperature, typically indicating that frosting is complete. However, due to factors such as ambient temperature disturbance and abnormal working condition of the evaporator, the frosting completion judgment only depends on the temperature value, and therefore the frosting completion judgment has the problem of insufficient accuracy. For this reason, the present embodiment determines the time point when the frost formation is completed by combining the drop characteristic of the detected temperature. The temperature drop characteristic of the evaporator surface during the frosting process can be known through the prior experiment, so as to determine the preset condition of the step. Referring to fig. 1, the controller 140 may perform this step by detecting a drop characteristic of the detected temperature.

In step 206, when it is judged that the frosting is completed, defrosting is performed to clean the evaporator.

In this step, the air conditioner may be put in a ventilation mode to defrost. Referring to fig. 1, the controller 140 may cause the inner fan 120 to have a higher rotational speed for ventilation. In one embodiment, the rotation speed of the inner fan 120 may also be increased as the room temperature increases. In the ventilation mode, the controller 140 may continuously detect whether the ventilation time reaches a preset time, and if so, the air conditioner may end the cleaning operation; otherwise, the air conditioner is enabled to continue ventilation operation.

Flow charts are used herein to illustrate operations performed by methods according to embodiments of the present application. It should be understood that the preceding operations are not necessarily performed in the exact order in which they are performed. Rather, various steps may be processed in reverse order or simultaneously. Meanwhile, other operations are added to or removed from these processes.

In the foregoing step 201, the operation of the air conditioner may be set according to the parameters of table 1 below.

TABLE 1

In table 1, the lower the rotation speed of the inner fan, the faster the frosting speed, but the less the moisture passing through the evaporator, the less the frosting amount; the higher the rotating speed of the inner fan is, the higher the heat exchange effect with the environment is, the slower the frosting speed is, but the more the frosting amount is. The EV valve is operated at a low opening, and the smaller the opening of the EV valve, the faster the indoor frost formation rate. The higher the rotating speed of the outer fan is, the better the heat exchange effect is, and the faster the frosting speed of the indoor unit is.

In table 1, the blade swing angle is an angle at which the air guide blade of the blade assembly of the indoor unit of the air conditioner swings downward with respect to the horizontal plane and stops. Fig. 5 is a sectional view of an indoor unit of an air conditioner according to an embodiment of the present invention. Referring to fig. 5, the air guide vane 511 of the vane assembly 510 of the indoor unit 500 swings downward by an angle a with respect to the horizontal plane S.

In the foregoing step 202, the target temperature may be determined with reference to the example of table 2 below

TABLE 2

Temperature condition	Humidity control	Target temperature
			10℃	RH85％	-29℃
15℃	RH45％	-7.5℃
			18℃	RH60％	-15℃
18℃	RH80％	-15.5℃
			24℃	RH50％	-3.5℃

In the aforementioned step 206, the operation of the air conditioner may be set according to the parameters of table 3 below.

TABLE 3

Optionally, after step 206, drying may also be performed for a predetermined time. The operation of the air conditioner in the drying stage may be set according to the parameters of table 4 below.

TABLE 4

Fig. 3 is a flowchart illustrating a frosting preset condition determining process of an air conditioner according to an embodiment of the present invention. This determination process may be performed, for example, in the controller 140 of fig. 1. Referring to fig. 3, the step of determining that the falling rate of the detected temperature reaches the predetermined condition may include

steps

301 and 303. Step 301-. In these steps, it is first judged in step 301 whether or not the rate of decrease in the detected temperature of the evaporator is increased, that is, whether or not the current rate of decrease V1 is greater than the last rate of decrease V2. If yes, go to step 302, and accumulate the increasing times n in step 302. In step 303, it is determined whether the number of times N of increase reaches a first threshold N, if yes, go to step 306 to determine that frosting is complete, otherwise, return to step 301.

The preset conditions of steps 301-303 conform to the typical temperature drop curve during frosting, but when unexpected temperature sharp changes occur, the temperature may not drop according to the preset conditions of steps 301-303. To this end, the preferred embodiment of the present invention provides additional predetermined conditions of step 304 and step 305. Step 301-. Specifically, when it is judged in step 301 that the rate of decrease in the detected temperature of the evaporator is not increased, it is judged in step 304 that the rate of decrease in the detected temperature of the evaporator is decreased or unchanged, and then the time t1 during which the rate of decrease or invariance is accumulated; in step 305, it is determined whether the reduced or unchanged time reaches a second threshold T1, if so, step 306 is entered, otherwise, step 304 is returned to.

It is understood that the preset conditions of steps 301-303 and 304-305 can be combined according to the situation.

Step 301-305 is executed under the condition that the detected temperature reaches the target temperature. However, in some cases, the detected temperature does not reach the target temperature, and for this reason, the preferred embodiment of the present invention additionally provides the frosting time point determination process as shown in fig. 4. Specifically, step 401 determines whether the detected temperature reaches the target temperature, and if so, step 402 is performed to determine whether the rate of decrease of the detected temperature reaches a predetermined condition, and the determination method can be as shown in fig. 3. Otherwise, step 403 is entered to obtain frosting time t 2. Here, the counting of the frosting time may be performed by a timer at the beginning of frosting. The timer may be provided inside the controller. Then, in step 404, it is determined whether the frosting time T2 reaches a third threshold T2, if yes, the step 405 is performed to determine that frosting is completed, otherwise, the step 401 is returned to.

This application uses specific words to describe embodiments of the application. Reference throughout this specification to "one embodiment," "an embodiment," and/or "some embodiments" means that a particular feature, structure, or characteristic described in connection with at least one embodiment of the present application is included in at least one embodiment of the present application. Therefore, it is emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, some features, structures, or characteristics of one or more embodiments of the present application may be combined as appropriate.

Although the present invention has been described with reference to the present specific embodiments, it will be appreciated by those skilled in the art that the above embodiments are merely illustrative of the present invention, and various equivalent changes and substitutions may be made without departing from the spirit of the invention, and therefore, it is intended that all changes and modifications to the above embodiments within the spirit and scope of the present invention be covered by the appended claims.

Claims

1. An automatic cleaning method for an evaporator of an air conditioner includes the following steps:

frosting the surface of the evaporator;

determining a target temperature of the evaporator;

continuously detecting the detection temperature of the evaporator;

calculating a rate of decrease of the detected temperature;

judging whether the detected temperature reaches the target temperature or not, and judging that the reduction rate of the detected temperature reaches a preset condition so as to judge that frosting is finished;

when it is judged that the frosting is completed, defrosting is performed to clean the evaporator.

2. The method of claim 1, wherein the method of determining the target temperature of the evaporator comprises: and calculating the target temperature according to the indoor temperature and the indoor humidity of the evaporator.

3. The method of claim 1, wherein the step of determining that the rate of decrease of the detected temperature reaches a preset condition when the detected temperature reaches the target temperature comprises:

a. accumulating the increasing times when the decreasing rate of the detection temperature of the evaporator is increased;

b. judging whether the increasing times reaches a first threshold value, if so, entering the step c, otherwise, returning to the step a;

c. and judging that frosting is finished.

4. The method of claim 3, wherein the step of judging that the falling rate of the detected temperature reaches a preset condition when it is judged that the falling rate of the detected temperature of the evaporator is not increased in step a when the detected temperature reaches the target temperature further comprises:

d. accumulating the time of decreasing or not changing when the decreasing rate of the detected temperature of the evaporator is decreased or not changed;

e. and d, judging whether the time reduced or unchanged reaches a second threshold value, if so, entering the step c, and otherwise, returning to the step d.

5. The method according to any one of claims 1 to 4, wherein frosting is judged to be completed when the detected temperature does not reach the target temperature and the frosting time reaches a third threshold value.

6. The method of claim 1, wherein a surface of the evaporator is frosted in a cooling mode or a frosting mode of the air conditioner, wherein an inner fan of the air conditioner is operated at a lowest wind level in the frosting mode.

7. The method of claim 1, wherein defrosting comprises placing the air conditioner in a ventilation mode.

8. The method as set forth in claim 7, wherein a rotation speed of an inner fan of the air conditioner is increased as the room temperature is increased in the ventilating mode.

9. The method of claim 7, further comprising continuously detecting whether a ventilation time reaches a preset time in the ventilation mode, and if so, causing the air conditioner to end a cleaning operation; otherwise, the air conditioner is enabled to continue ventilation operation.

10. The method as claimed in claim 1, wherein the indoor unit of the air conditioner includes a blade assembly, and the air guide blade of the blade assembly swings downward at a predetermined angle with respect to a horizontal plane when frost is formed and/or defrosted.

11. An automatic cleaning apparatus for an evaporator of an air conditioner, comprising an evaporator, an internal fan, and a controller, wherein the controller controls the operation of the evaporator and the internal fan according to the method of any one of claims 1 to 10.

12. An air conditioner including an indoor unit, the indoor unit comprising:

the automatic cleaning device of claim 11; and

and the air guide blades of the blade assembly swing downwards to form a preset angle relative to the horizontal plane.