A defrosting control method and a refrigerator

Abstract

This invention discloses a defrosting control method and a refrigerator, relating to the field of refrigerator technology. The invention includes: detecting the flow rate of defrosting water at the drain pipe using a flow rate detection device; after defrosting begins for time t1, detecting whether there is a water flow signal; if yes, defrosting continues; otherwise, defrosting stops; step five: after defrosting begins for time t2, detecting the water flow rate and determining whether the water flow rate is greater than a first preset threshold V1; if not, after defrosting begins for time t3, detecting whether there is a no-water flow signal; if yes, continuously detecting the water flow rate and determining whether the real-time water flow rate is less than a second preset threshold V2; if so, defrosting stops. This invention, by detecting the flow rate of defrosting water and comparing it with the first and second preset thresholds V1 and V2, achieves the judgment of the defrosting status, solving the problems of poor accuracy and incomplete or excessive defrosting in existing defrosting end judgment methods.

Description

Technical Field

[0001] This invention belongs to the field of refrigerator technology, and in particular relates to a defrosting control method and a refrigerator. Background Technology

[0002] Currently, household refrigerators have gradually shifted from direct cooling to frost-free cooling. Frost-free refrigerators achieve frost-free operation by electrically heating a defrost heater installed at the bottom of the evaporator. During defrosting, the frost layer on the evaporator melts, and the defrost water is drained into a drip tray through a drain pipe. The defrosting requirement of a refrigerator evaporator is generally determined by a combination of factors, including the cumulative operating time of the refrigerator, the number of times the door is opened and closed, the ambient temperature, and the ambient humidity.

[0003] In existing technologies, the defrosting cycle typically ends when the temperature detected by the temperature sensor installed on the evaporator exceeds a fixed threshold. However, since the frost thickness on the refrigerator evaporator is not necessarily uniform across different locations, and the temperature sensor on the evaporator only obtains the temperature of a localized area, this method of determining the end of the defrosting cycle is inaccurate. This can easily lead to incomplete defrosting of the refrigerator evaporator, resulting in residual frost, or excessive defrosting, causing the heater to burn out. Summary of the Invention

[0004] The purpose of this invention is to provide a defrosting control method that detects the flow rate of defrosting water and compares the flow rate with the magnitude of a first preset threshold V1 and a second preset threshold V2 to determine the defrosting status. This solves the problems of poor accuracy and incomplete or excessive defrosting in existing defrosting end determination methods.

[0005] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0006] This invention relates to a defrosting control method, comprising:

[0007] Step 1: Determine if the defrosting conditions are met. If yes, proceed to the next step; otherwise, maintain the current state.

[0008] Step 2: Start the defrosting cycle. The defrosting heater is powered on to begin heating and defrosting the evaporator.

[0009] Step 3: Detect the flow rate of defrosting water at the drain pipe using a flow rate detection device;

[0010] Step 4: After defrosting begins, at time t1, check for water flow signal. If yes, continue defrosting; otherwise, stop defrosting.

[0011] Step 5: After defrosting begins, at time t2, detect the water flow rate and determine whether the water flow rate is greater than the first preset threshold V1. If yes, proceed to step 7; otherwise, proceed to step 6.

[0012] Step Six: After defrosting begins, at time t3, check for a no-water-flow signal. If yes, proceed to Step Seven; otherwise, stop defrosting.

[0013] Step 7: Continuously monitor the water flow rate and determine whether the real-time water flow rate is less than the second preset threshold V2. If so, determine that defrosting is complete and stop defrosting. If not, continue to execute Step 7.

[0014] In a preferred embodiment of the present invention, the t1 time is 3 to 5 minutes.

[0015] As a preferred technical solution of the present invention, in step seven, the water flow velocity is calculated every t4 time and compared with the second preset threshold V2.

[0016] In a preferred embodiment of the present invention, the t4 time is 1 to 2 minutes.

[0017] A refrigerator that uses the defrosting control method described above.

[0018] The present invention has the following beneficial effects:

[0019] This invention detects the flow rate of defrosting water in the drain pipe and compares the flow rate with a first preset threshold V1 and a second preset threshold V2. By observing the trend of the flow rate change, it accurately judges the defrosting process, effectively avoiding incomplete defrosting leading to residual frost and excessive defrosting causing dry burning of the heater. This is beneficial to improving the overall cooling effect and service life.

[0020] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a flowchart of a defrosting control method according to the present invention. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1

[0025] Please see Figure 1 As shown, the present invention is a defrosting control method, including step one: after the refrigerator is powered on, the compressor runs and the refrigerator cools normally; the refrigerator is judged by the existing judgment conditions for the refrigerator to need to defrost, and it is judged whether the defrosting conditions are met. If yes, the next step is executed; if no, the status quo is maintained.

[0026] Step 2: Start the defrosting cycle. The defrosting heater is powered on to begin heating the evaporator for defrosting.

[0027] Step 3: Detect the flow rate of defrosting water at the drain pipe using a flow rate detection device. The refrigerator defrost heater control device includes the refrigerator main control MCU, defrost heater control circuit, defrost heater, and flow rate detection device. The main control MCU determines whether the refrigerator meets the defrosting conditions. If the conditions are met, it controls the defrost heater to be powered on to begin defrosting.

[0028] The flow rate detection device includes a pair of infrared transceivers, a voltage comparator circuit, and a mounting structure for the infrared transceivers on the defrost drain pipe. Based on the principle that infrared light refracts in liquids, when defrost water drips, the infrared transceivers do not receive infrared light and are switched off; when no defrost water drips, the infrared transceivers receive infrared light and are switched on.

[0029] The threshold reference, formed by the output of the infrared diode and the voltage divider of the resistor, is fed into the input of the comparator circuit. When water droplets fall, the comparator outputs a high-level signal "1", and when no water droplets fall, the comparator outputs a low-level signal "0". When the heater is powered on to begin defrosting, the flow rate detection device starts to detect the defrosting water flow rate.

[0030] Step 4: After defrosting begins, time t1 (3-5 minutes) is used to check for water flow. If there is a water flow signal, defrosting continues. If not, it means that no defrosting water is produced, indicating that the frost on the evaporator has completely melted, and defrosting is stopped.

[0031] Step 5: After defrosting begins, at time t2, detect the water flow rate and determine if it exceeds the first preset threshold V1. If it does, it indicates a large amount of defrosting water and the frost is continuously melting; proceed to Step 7. If not, it indicates a small amount of defrosting water and the degree of frost melting is decreasing; proceed to Step 6. Note that time t2 is greater than time t1.

[0032] Step Six: After defrosting begins, at time t3, check for a signal indicating no water flow. If yes, it means defrosting water is still being produced, and proceed to Step Seven. If no, it means no defrosting water is being produced, and the frost has completely melted, so stop defrosting. Note that time t3 is longer than time t2.

[0033] Step 7: Continuously monitor the water flow rate and determine whether the real-time water flow rate is less than the second preset threshold V2. If so, determine that defrosting is complete and stop defrosting. If not, continue to execute Step 7.

[0034] If the first preset threshold V1 is greater than the second preset threshold V2 and the water flow rate is less than the second preset threshold V2, it indicates that the defrosting water volume is continuously decreasing and is less than the second preset threshold V2. Therefore, it is determined that the defrosting water at this time is a small amount of residual defrosting water, and it is determined that the frost on the evaporator has completely melted, the defrosting is complete, and the defrosting is stopped.

[0035] When the water flow rate is greater than the second preset threshold V2, it indicates that the defrosting water volume is continuously decreasing, but the water volume has not reached the standard for judging that the frost on the evaporator has completely melted. Therefore, the water flow rate is continuously detected, and the water flow rate is calculated every t4 time and compared with the second preset threshold V2.

[0036] The t4 time is 1 to 2 minutes. The water flow rate is detected and calculated every 1 minute until the water flow rate is less than the second preset threshold V2. At this point, it is determined that the frost on the evaporator has completely melted, and defrosting is stopped.

[0037] Example 2

[0038] A refrigerator that employs the defrosting control method described in Embodiment 1, and includes the refrigerator main control MCU, defrosting heater control circuit, defrosting heater, and flow rate detection device described in Embodiment 1.

[0039] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0040] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A defrosting control method, characterized in that, Includes the following steps: Step 1: Determine if the defrosting conditions are met. If yes, proceed to the next step; otherwise, maintain the current state. Step 2: Start the defrosting cycle. The defrosting heater is powered on to begin heating and defrosting the evaporator. Step 3: Detect the flow rate of defrosting water at the drain pipe using a flow rate detection device; Step 4: After defrosting begins, at time t1, check for water flow signal. If yes, continue defrosting; otherwise, stop defrosting. The t1 time is 3-5 minutes. Step 5: After defrosting begins, at time t2, detect the water flow rate and determine whether the water flow rate is greater than the first preset threshold V1. If yes, proceed to step 7; otherwise, proceed to step 6. Step Six: After defrosting begins, at time t3, check for a no-water-flow signal. If yes, proceed to Step Seven; otherwise, stop defrosting. Step 7: Continuously monitor the water flow rate and calculate the water flow rate every t4 time interval to determine whether the real-time water flow rate is less than the second preset threshold V2. If so, it is determined that defrosting is complete and defrosting is stopped. If not, continue to execute Step 7. The t4 time interval is 1 to 2 minutes.

2. A refrigerator, characterized in that, The refrigerator uses the defrosting control method as described in claim 1.

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