[0001] This invention refers to a cooling apparatus for defrosting after detecting frost
according to claim 1.
Background of the Invention
[0002] 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.
[0003] 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.
[0004] 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
[0005] 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
[0006] 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.
[0007] 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.
[0008] Further preferred embodiments are subject-matter of dependent claims and/or of the
following specification parts.
[0009] 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.
[0010] 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.
[0011] The invention is just exemplarily described with respect to the attached figures
in the following.
Brief Description of the Drawings
[0012]
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
[0013] 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.
[0014] 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.
[0015] 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.
[0016] 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).
[0017] 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.
[0018] 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.
[0019] 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.
[0020] 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.
[0021] 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
[0022]
- 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
1. 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.
2. The cooling apparatus as claimed in claim 1, wherein the bimetals 3 and the evaporator
coil 2 are perpendicular to each other.
3. 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.
4. The cooling apparatus as claimed in claim 1, wherein the application of voltage on
the bimetals 3 controlled by a microcontroller unit 8.
5. The cooling apparatus as claimed in claim 4, wherein the application of voltage on
the bimetals 3 varies according to degree of icing.