EP3527917A1

EP3527917A1 - Cooling apparatus for defrosting

Info

Publication number: EP3527917A1
Application number: EP18157172.0A
Authority: EP
Inventors: Mert Serdar BILGIN; Yusuf AK
Original assignee: Vestel Elektronik Sanayi ve Ticaret AS
Current assignee: Vestel Elektronik Sanayi ve Ticaret AS
Priority date: 2018-02-16
Filing date: 2018-02-16
Publication date: 2019-08-21

Abstract

The present invention refers to a cooling apparatus for defrosting after detecting frost. The cooling apparatus according to the present invention preferably comprises of an evaporator 1, an evaporator coil 2, a compressor 4, a condenser 5, a condenser coil 6 and a receiver dryer 7. The cooling apparatus further includes plurality of bimetals 3, wherein the bimetals 3 are placed on the evaporator coil 2. The bimetals 3 are activated by applying voltage from a power supply 10. The bimetals 3 are configured to bend according to the application of voltage and thereby applying pressure on frosted surface formed on the evaporator coil 2 and breaking the ice formed on the evaporator coil 2.

Description

This invention refers to a cooling apparatus for defrosting after detecting frost according to claim 1.

Background of the Invention

White goods are electronic devices such as air conditioners and refrigerators that are mostly used to reduce temperature. A common problem experienced by such white goods is the formation of frost on the indoor unit coil. Defrosting is the process of removing or freeing the frost formed on the indoor unit coil. Various methods for defrosting are known in the prior art such as providing separate evaporator coils, reversing the cooling cycle, wherein the indoor unit is heated instead of cooled and outdoor unit is cooled instead of heating. However, reversing of the cooling cycle manually causes increase in power consumption over the time and reversing of the cooling cycle automatically increases electrical and mechanical complexity. The defrosting method has to avoid the reversing of the cooling cycle manually or automatically.
Prior art US 4741175 A discloses a refrigerator that includes a freezer compartment, a fresh food compartment and an evaporator chamber. Air is circulated between the chamber and each compartment. Air from the fresh food compartment is returned through a return duct. The evaporator has one section in the evaporator chamber and another section in the return air duct so that the fresh food compartment return air passes over both of the evaporator sections while the freezer return air passes over only the evaporator section in the evaporator chamber.
Another prior art US 6266969 B1 relates to a device for rapidly defrosting a refrigerator compartment, such as a freezer compartment or the like, said compartment comprising a plurality of adjacent walls, in correspondence with at least one of said walls there being arranged a hairpin coil evaporator for a static refrigerator, or a part of an evaporator of forced-air type, within a refrigeration circuit comprising a motor-compressor unit, said device comprising heating means arranged in correspondence with at least one of said walls and/or with the evaporator, said heating means being electrically powered via an electrical supply circuit associated with the refrigerator; the heating means are at least one resistance element of PTF (polymer thin/thick film) type.

Object of the Invention

It is therefore the object of the present invention to provide a cooling apparatus for defrosting that enables breaking of the frost formed on the evaporator coil after detecting the frost and thereby avoiding reversing of the cooling cycle manually or automatically.

Description of the Invention

The before mentioned object is solved by a cooling apparatus for defrosting that enables breaking of the frost formed on the evaporator coil after detecting the frost and thereby avoiding reversing of the cooling cycle manually or automatically according to claim 1. The present invention refers to a cooling apparatus for defrosting after detecting frost. The cooling apparatus according to the present invention preferably comprises of an evaporator, an evaporator coil, a compressor, a condenser, a condenser coil and a receiver dryer. The cooling apparatus further includes plurality of bimetals, wherein the bimetals are placed on the evaporator coil. The bimetals are activated by applying voltage from a power supply. Further, the bimetals are configured to bend according to the application of voltage and thereby applying pressure on frosted surface formed on the evaporator coil and breaking the frost formed on the evaporator coil.
This solution is beneficial since such a cooling apparatus enables breaking of the frost on the evaporator coil and thereby avoids reversing of the cooling cycle manually. The application of voltage on the bimetals causes the bimetals to bend accordingly and thereby applies pressure on the frosted surface of the evaporator coil and breaks the frost formed on the evaporator coil and hence reversing of the cooling cycle manually or automatically for defrosting is avoided. Additionally, implementation of such a cooling apparatus is simple and effective.
Further preferred embodiments are subject-matter of dependent claims and/or of the following specification parts.
According to a preferred embodiment of the present invention the bimetals and evaporator coil are perpendicular to each other. The bimetals are arranged in the form of loop. The application of voltage on the bimetals is controlled by a microcontroller unit and the application of voltage on the bimetals varies according to degree of frosting.
Further benefits, goals and features of the present invention will be described by the following specification of the attached figures, in which components of the invention are exemplarily illustrated. Components of the devices and method according to the inventions, which match at least essentially with respect to their function, can be marked with the same reference sign, wherein such components do not have to be marked or described in all figures.
The invention is just exemplarily described with respect to the attached figures in the following.

Brief Description of the Drawings

Fig. 1 illustrates an exemplary model of a cooling apparatus 100 that shows position of bimetals when there is no frost, according to the present invention;
Fig. 1 (a) illustrates an exemplary model of a cooling apparatus 100 (a) that shows bending of bimetals when low voltage is applied, according to the present invention;
Fig. 1(b) illustrates an exemplary model of a cooling apparatus 100 (b) that shows bending of bimetals when medium voltage is applied, according to the present invention;
Fig. 1(c) illustrates an exemplary model of a cooling apparatus 100 (c) that shows bending of bimetals when high voltage is applied, according to the present invention; and
Fig. 2 illustrates a block diagram of a defrosting method 200, according to the present invention.

Detailed Description of the Drawings

Fig. 1 illustrates exemplary model of a cooling apparatus 100 that indicates position of bimetals when there is no frost, according to the present invention. The present invention preferably comprises of an evaporator 1, an evaporator coil, a compressor 4, a condenser 5, a condenser coil 6 and a receiver dryer 7. According to the embodiment of the invention, the cooling apparatus further includes plurality of bimetals 3, wherein the bimetals are placed on the evaporator coil 2. In an embodiment, the bimetals 3 and the evaporator coil 2 are perpendicular to each other and the bimetals 3 are arranged in the form of loop. The bimetals 3 are activated by applying voltage from a power supply 10. The bimetals 3 are configured to bend according to the application of voltage and thereby applying pressure on frosted surface formed on the evaporator coil 2 and breaking the ice formed on the evaporator coil 2.
In particular, the application of the voltage on the evaporator coil is controlled by a microcontroller unit (MCU) 8 and the application of the voltage on the evaporator coil varies according to the degree of icing. The MCU 8 triggers relays 9 and thereby activates bimetals by applying constant voltage according to the degree of frosting. Fig. 1 shows the position of the bimetals 3 when there is no frost on the evaporator coil 2. Since no frost is detected on the evaporator coil 2, voltage is not applied on the bimetals 3 and therefore bimetals 3 remain in the same position without any bending.
Fig. 1(a) illustrates an exemplary model of a cooling apparatus 100 (a) that shows bending of bimetals when low voltage is applied, according to the present invention. A frost breaking is performed automatically only after detecting frosting instead of melting the frost. That is, the cooling cycle is not reversed manually or automatically for defrosting. In order to achieve this, the cooling apparatus utilizes bimetals 3, MCU 8, relays 9 and power supply 10. After detecting low degree of frost on the evaporator coil 2, the MCU 8 triggers the relays 9 and thereby activates bimetals 3(a) by applying a low voltage 10(a) on the bimetals 3(a). The bimetals 3 are heat sensitive material and have a certain resistance value and therefore start bending 3 (a) with the application of low voltage 10(a). The bimetals 3 (a) applies pressure on frost on the evaporator coil 2 and breaks the frost. The bending of bimetals is less 3(a) as the applied voltage 10 (a) and the degree of frosting is less.
When the presence of frost is detected even after applying a low voltage 10(a) then the application of voltage is varied 10(b). Fig. 1(b) illustrates an exemplary model of a cooling apparatus 100 (b) that shows bending of bimetals when medium voltage is applied, according to the present invention. After detecting frost on the evaporator coil even after applying voltage 10(a) on the bimetals, the MCU 8 triggers the relays 9 and thereby activates bimetals 3 (b) by applying slightly greater voltage 10(b) on the bimetals 3(b). The bimetals starts bending 3(b) more with the application of voltage 10(b) in a curved manner. Therefore, the bimetals 3(b) apply more pressure on frost on the evaporator coil 2 and thereby breaking the frost. The bending of bimetals 3(b) seems to be more compared to the bending of bimetals 3(a) applied with low voltage 10 (a).
If the frosting sensation continues, voltage is further increased and a high voltage 10(c) is applied on the bimetals 3(c). Fig. 1 (c) illustrates an exemplary model of a cooling apparatus 100 (c) that shows bending of bimetals when high voltage is applied in a circular manner, according to the present invention. When the frosting sensation continues, the MCU 8 triggers the relays 9 and thereby activates bimetals 3 (c) by applying high voltage 10(c) on the bimetals 3(c) in a circular manner. The bimetals starts bending 3(c) deeper with the application of voltage 10(c). Therefore, the bimetals 3(c) applies high pressure on frost on the evaporator coil 2 and thereby breaks the frost. Therefore, depending upon the degree of frosting detected the voltage is controlled by the MCU and voltage is applied according on the bimetals for breaking the frost.
This solution is beneficial since such a cooling apparatus 100(a, b, c) enables breaking of the frost on the evaporator coil 2 and thereby avoids reversing of the cooling cycle manually. The application of voltage on the bimetals 10(a, b, c) causes the bimetals to bend 3(a, b, c) accordingly and thereby applies pressure on the frosted surface of the evaporator coil 2 and breaks the frost formed on the evaporator coil 2. Thus, the bimetals 3 are arranged in such a form on the evaporator coil (2) that the bimetals can change its form from straight to curved and into circular depending on the applied voltage. Hence reversing of the cooling cycle manually or automatically for defrosting is avoided. Additionally, implementation of such a cooling apparatus is simple and effective.
Fig. 2 illustrates a block diagram of a defrosting method 200, according to the present invention. The frost condition is detected 11 and depending upon the degree of frosting the MCU starts defrost algorithm 12. The relays are triggered by the MCU 13 and the bimetals are activated 14. The bimetals bends according to the applied voltage 15 and applies pressure on frost on the evaporator coil and thereby breaks the frost 16.
Thus, the present invention that provides a cooling apparatus for defrosting after detecting the frost enables breaking of the frost formed on the evaporator coil by avoiding reversing of the cooling cycle manually or automatically. The cooling apparatus according to the present invention preferably comprises of an evaporator 1, an evaporator coil 2, a compressor 4, a condenser 5, a condenser coil 6 and receiver dryer 7. The cooling apparatus further includes plurality of bimetals 3, wherein the bimetals 3 are placed on the evaporator coil 2. The bimetals 3 are activated by applying voltage from a power supply 10. The bimetals 3 are configured to bend according to the application of voltage and thereby applying pressure on frosted surface formed on the evaporator coil 2 and breaking the ice formed on the evaporator coil 2.
The subject-matter of the application provides a defrosting method without melting of the frost and without avoiding reversing of the cooling cycle manually or automatically.

List of reference numbers

1: Evaporator
2: Evaporator coil
3: Bimetals
3(a): Less bending of the bimetals
3(b): Medium bending of the bimetals
3(c): High bending of the bimetals
4: Compressor
5: Condenser
6: Condenser coil
7: Receiver dryer
8: Microcontroller unit (MCU)
9: Relays
10: Power supply
10(a): Low power supply
10(b): Medium power supply
10(c): High power supply
11: Frost condition is detected
12: MCU starts defrosting algorithm
13: Relays triggered by MCU
14: Bimetals are activated
15: Bimetals bends according to voltage level
16: Ice breaking performed using bimetals

Claims

A cooling apparatus for defrosting after detecting frost, wherein the cooling apparatus comprising of:
an evaporator 1, an evaporator coil 2, a compressor 4, a condenser 5, a condenser coil 6 and a receiver dryer 7,

characterized in that

the cooling apparatus further includes plurality of bimetals 3, wherein the bimetals 3 are placed on the evaporator coil 2,

wherein the bimetals 3 are activated by applying voltage from a power supply 10, and

wherein the bimetals are configured to bend according to the application of voltage and thereby applying pressure on frosted surface formed on the evaporator coil 2 and breaking the ice formed on the evaporator coil 2.
The cooling apparatus as claimed in claim 1, wherein the bimetals 3 and the evaporator coil 2 are perpendicular to each other.
The cooling apparatus as claimed in claim 2, wherein the bimetals 3 are arranged in such a form on the evaporator coil (2) that the bimetals can change its form from straight to curved and into circular depending on the applied voltage.
The cooling apparatus as claimed in claim 1, wherein the application of voltage on the bimetals 3 controlled by a microcontroller unit 8.
The cooling apparatus as claimed in claim 4, wherein the application of voltage on the bimetals 3 varies according to degree of icing.