U.S. patent application number 11/883424 was filed with the patent office on 2008-06-26 for multi-temperature control refrigerator comprising an ice machine.
Invention is credited to Guangming Dang, LingYun Li, Dongning Wang, ZhiChun Zhang.
Application Number | 20080148745 11/883424 |
Document ID | / |
Family ID | 36740036 |
Filed Date | 2008-06-26 |
United States Patent
Application |
20080148745 |
Kind Code |
A1 |
Zhang; ZhiChun ; et
al. |
June 26, 2008 |
Multi-Temperature Control Refrigerator Comprising an Ice
Machine
Abstract
The present invention relates to a multi-temperature control
refrigerator, in which an ice machine is installed and the cooling
mode of the refrigerator is a mixed air-cooling and direct cooling
mode. Particularly, the present invention relates to a refrigerator
having ice-making function, in which the refrigeration cycle is a
dual cycle and two different evaporators are included. Due to that
the ice making room of the of the refrigerator of the present
invention adopts a mixed air-cooling and direct cooling mode, and
that impulse solenoid valves and dual temperature control device
are introduced to the dual cycle system, the energy is optimally
distributed and utilized, the fluctuation of temperature is small
and the ice making efficiency of the ice making room and the
quality of the ice cubes are much improved. And the whole
refrigerator makes less noise, consumes fewer refrigerants and
makes ice of good quality rapidly.
Inventors: |
Zhang; ZhiChun; (Shandong,
CN) ; Wang; Dongning; (Shandong, CN) ; Li;
LingYun; (Shandong, CN) ; Dang; Guangming;
(Shandong, CN) |
Correspondence
Address: |
TROXELL LAW OFFICE PLLC
5205 LEESBURG PIKE, SUITE 1404
FALLS CHURCH
VA
22041
US
|
Family ID: |
36740036 |
Appl. No.: |
11/883424 |
Filed: |
November 28, 2005 |
PCT Filed: |
November 28, 2005 |
PCT NO: |
PCT/CN2005/002028 |
371 Date: |
July 31, 2007 |
Current U.S.
Class: |
62/113 ; 62/186;
62/441; 62/515 |
Current CPC
Class: |
F25D 17/065 20130101;
F25D 2317/061 20130101; F25D 11/022 20130101; F25D 2400/30
20130101; F25C 2400/10 20130101 |
Class at
Publication: |
62/113 ; 62/441;
62/515; 62/186 |
International
Class: |
F25D 17/06 20060101
F25D017/06; F25D 11/02 20060101 F25D011/02; F25B 41/00 20060101
F25B041/00; F25B 39/02 20060101 F25B039/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 31, 2005 |
CN |
200510004995.X |
Claims
1. A multi-temperature control refrigerator, in which an ice
machine is installed and the cooling mode of the refrigerator is a
mixed air-cooling and direct cooling mode, comprises a refrigerator
compartment and a freezer compartment which further comprises an
ice making room, wherein said refrigerator compartment and freezer
compartment adopt direct cooling mode for refrigeration and said
ice making room adopts a mixed air-cooling and direct cooling mode
for refrigeration.
2. A refrigerator as claimed in claim 1, wherein said freezer
compartment adopts fin type evaporator; the fin pitch of said fin
type evaporator is over 6 mm, preferably 6-8 mm; said fin is
preferably spiral fins.
3. A refrigerator as claimed in claim 1, wherein said ice making
room is mounted with a door which encloses the space of the ice
making room; said ice making room is set at the upper part of the
freezer compartment.
4. A refrigerator as claimed in claim 1, wherein in the space where
the evaporator of said freezer compartment presents, a air inlet
(6) and air outlet (7) connecting the ice making room are
installed; a door is preferably installed at the air outlet (7)
and/or the air inlet (6) of the ice making room.
5. A refrigerator as claimed in claim 1, wherein said refrigerator
compartment adopts plate type evaporator which sticks to the inner
liner of the refrigerator compartment; said freezer compartment
adopts a mixed air-cooling and direct cooling mode and one side of
the evaporator also sticks to the inner liner of the freezer
compartment while behind the other side there is a gap; a heating
tube is preferably set on the evaporator of the freezer compartment
and the form of the heating tube is determined according to the
form of the evaporator.
6. A refrigerator as claimed in claim 1, wherein the heater for
defrosting the evaporator in said freezer compartment is in contact
with the water inlet of the ice machine.
7. A refrigerator as claimed in claim 1, wherein said freezer
compartment and refrigerator compartment is each installed with
temperature sensing units and an action sensor is set inside the
ice making room.
8. A refrigerator as claimed in claim 1, wherein said refrigerator
adopts dual cycle refrigeration system and an evaporator that is
large in area is connected to the bypass circuit as an additional
evaporator of the refrigerator compartment.
9. A refrigerator as claimed in claim 1, wherein said refrigerator
comprises an additional evaporator for the refrigerator
compartment; the outlet of the compressor is connected to the inlet
of the condenser; the outlet of the condenser is connected to the
inlet of the desiccation filter; the outlet of the desiccation
filter is connected to the three-way solenoid valve; one outlet of
the three-way solenoid valve is connected to the inlet of the main
capillary tube, the other outlet is connected to the inlet of the
bypass capillary tube; the outlet of the main capillary tube is
connected to the inlet of the freezing evaporator; the outlet of
the bypass capillary tube is connected to the inlet of the
additional refrigerating evaporator; the outlets of the freezing
evaporator and the additional refrigerating evaporator are both
connected to the inlet of the refrigerating evaporator; the outlet
of the refrigerating evaporator is connected to the inlet of the
water storage apparatus and; the outlet of the water storage
apparatus is connected to one end of the air intake tube and the
other end is connected to the inlet of the compressor.
10. A working method for the refrigerator as claimed in claim 1,
wherein whether the ice making process is to be carried out or not
is determined when the refrigerator is operating and if the ice
making process is to be commenced, the evaporator of the freezer
compartment is started and the fan is also started to cool the ice
making room quickly to an ice-making quick-freezing temperature;
when determining the ice making room is at a
temperature-maintaining state or not and if the temperature doesn't
reach the preset ice-making maintaining temperature, the evaporator
of the freezer compartment is started and the fan is also started
to cool the ice making room quickly to the ice-making maintaining
temperature.
11. A method as claimed in claim 10, wherein the quick-freezing
temperature and the maintaining temperature of the ice making room
are set below the preset temperature of the freezer compartment;
preferably, the maintaining temperature of the ice making room is
the same as the preset temperature of the freezer compartment.
12. A method as claimed in claim 11, wherein the quick-freezing
temperature and the maintaining temperature of the ice making room
are set distinctively below the preset temperature of the freezer
compartment.
13. A method as claimed in claim 10, wherein when the freezer
compartment has reached the preset temperature and the refrigerator
compartment hasn't, the bypass circuit is turned on; the main
evaporator of the refrigerator compartment of the main circuit,
which has a relative small area for evaporation, is combined with
an additional evaporator of the refrigerator compartment, which has
a relative larger area for evaporation, and forms an evaporator of
the refrigerator compartment that has very large evaporation area
so as to adjust the temperature of the refrigerator compartment
rapidly.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a multi-temperature control
refrigerator, in which an ice machine is installed and the cooling
mode of the refrigerator is a mixed air-cooling and direct cooling
mode. Particularly, the present invention relates to a
multi-temperature control refrigerator having ice-making function,
in which the refrigeration cycle is a dual cycle and the cooling
mode is a mixed air-cooling and direct cooling mode.
[0003] 2. Description of the Related Art
[0004] While living standards are improved with each passing day,
ice cubes are required more and more in our daily lives. The fact
that a major part of the operation of ice is machines in the past
involves manual work is not satisfactory but automatic ice machines
facilitate the use of ice cubes greatly, because the whole
ice-making process of an automatic ice machine doesn't involve any
manual intervention.
[0005] Automatic ice machines in the prior art can be divided into
two types, which are specified as follows:
[0006] The control device of the first type ice machine is
integrated into itself and there is no need to implement the
control of the ice-making system separately through the main
control panel of the refrigerator. The installation method of the
first type ice machine is such that ice machine is an integrated
and independent accessory of the refrigerator, which can be
installed at any time if there are preserved joints and space for
the ice machine in the refrigerator and there is no need to make
molds for plastic components. The ice is removed from the first
type ice machine by heating. Tap water is fed into the first type
ice machine through water valve. It is also possible to hold water
in a water storage device and utilize a pump to feed the water into
the first type ice machine. This type of ice machines have an
integrated ice-making system and need only the electric supply of
220V or 115V is needed for operation. They can also be mounted in
mechanical refrigerators and other advantages are that no extra
control unit is required; no extra molds are needed to be made; the
installation of the ice machine requires only two screws; it is
very simple to use and it is also highly reliable. But the
disadvantages are that the volume of the ice machine is bulky and
too much space is taken up. Please refer to the drawing for the
first type ice machine, wherein ice machine 22, ice making box 23,
ice detecting lever 24, ice storage box 25 and ice cubes 26 are
comprised. A substantially sealed ice-making room is installed in
the refrigerator. The ice machine 22, under which the ice making
box 23 is placed, is screwed onto an appropriate place of the inner
wall of the ice-making room. Freezing is carried out after water is
injected from the water storage device to the ice making box. When
the water in the ice making box 23 is turned into ice, ice cubes 26
are forced down into the ice storage box 25 by using a lever or
reversing the ice making box. The ice storage box 25 is deemed full
when the ice detecting lever is raised to a height due to the ice
cubes 26 and the ice machine stops working. Ice storage box is
taken out when ice cubes are needed.
[0007] The second type ice machine is only an ice removing
mechanism, wherein all the control means are implemented through
the main control panel of the refrigerator. It is necessary to
design the installation structure of the ice machine and other
plastic components such as the ice making box due to that the ice
machine is only an ice removing mechanism. The ice is removed from
the second type ice machine by torque force. The water source of
this type of refrigerator is the water held beforehand in a water
tank inside the refrigerator compartment, which is fed by pumps and
it is also achievable to use tap water according to requirements.
This type of ice machine is actually a mere ice removing mechanism
and requires the addition of many components, a control circuit and
a testing circuit before automatic ice-making can be achieved. The
structure of this type of ice machine is complex and many parts and
components are involved and the reliability is low. But the volume
of the ice machine is smaller and less space is occupied.
[0008] The present invention is an improvement to the first type
ice machine. Particularly, the present invention is an improvement
to the refrigerator where the first type ice machine is installed.
In such a refrigerator, ice machine is often placed in the freezer
compartment and, in order to prevent tainting by odor or due to
other reasons, it is also feasible to set up a relatively isolated
space in the freezer compartment, i.e. ice-making room, to install
the ice machine. Generally, such an ice-making room comprises a
door to separate the space of different functions. But it is hard
to coordinate the interrelationship between the temperature of the
freezer compartment and the refrigerating effect of the ice-making
room when the requirement of the freezer compartment and that of
the ice machine are different, because the freezing process of the
ice machine set inside the freezer compartment adopts the
refrigeration system of the freezer compartment. In order to
overcome the defects existed in the prior art, the present
invention is proposed.
SUMMARY OF THE INVENTION
[0009] The primary object of the present invention is to provide a
refrigerator with an ice machine where an independent ice making
room is comprised.
[0010] Another object of the present invention is to provide a
refrigerator where a refrigerating source is solely provided for
the independent ice making room.
[0011] It is yet another object of the present invention to provide
a refrigerator where two different cooling modes, i.e. air-cooling
mode and direct cooling mode, are provided to the two rooms of the
freezer compartment using one evaporator.
[0012] The objects of the present invention can be achieved
according to the following description. Said refrigerator can be
divided into freezer compartment 1 and refrigerator compartment 2.
In the freezer compartment 1, an ice making room is usually set at
the upper-left part when the door of the refrigerator is opened to
the left. Said ice making room is installed with a door 9 so as to
prevent the flow of the refrigerating effect and the tainting by
odor. An ice machine is mounted in the ice making room and an ice
storage box is arranged below said ice machine. Both the freezer
compartment and refrigerator compartment adopt direct cooling mode
and an air inlet and an air outlet connected with the ice making
room are set in the space where the evaporator of the freezer
compartment is presented. The ice making room is deep cooled using
air-cooling mode when needed.
[0013] Particularly, the present invention involves a
triple-temperature control refrigerator comprising an ice machine
where the cooling mode is a mixed air-cooling and direct cooling
mode.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] By referring to the description of the drawings set out as
below and in combination with the following detailed description, a
more clarified appreciation of the present invention can be
obtained, wherein
[0015] FIG. 1(a) illustrates a schematic diagram of the
refrigerator of the present invention where an ice machine is
comprised;
[0016] FIG. 1(b) illustrates a cutaway view of the refrigerator of
the present invention where the cooling mode is a mixed air-cooling
and direct cooling mode and multi-temperature control function is
enabled;
[0017] FIG. 2(a) illustrates the effect of the velocity of the air
flow on the efficiency of the fin type evaporator;
[0018] FIG. 2(b) illustrates the effect of the relative humidity of
the air on the efficiency of the fin type evaporator;
[0019] FIG. 2(c) illustrates the effect of the space between the
fins on the efficiency of the fin type evaporator;
[0020] FIG. 2(d) illustrates the effect of the velocity of the air
flow on the average heat exchange coefficient of the air side;
[0021] FIG. 2(e) illustrates the effect of the relative humidity of
the air on the average heat exchange coefficient of the air
side;
[0022] FIG. 2(f) illustrates the effect of the space between the
fins on the average heat exchange coefficient of the air side;
[0023] FIG. 3 illustrates a schematic diagram of the dual cycle
refrigerating system of the present invention;
[0024] FIG. 4 illustrates a cutaway view of the ice machine of the
present invention.
BRIEF DESCRIPTION OF REFERENCE NUMERAL
[0025] Freezer compartment 1; refrigerator compartment 2; ice
making room 3; evaporator 4; plate type evaporator 5; air inlet 6;
air outlet 7; fan 8; door of ice making room 9; compressor 11;
condenser 12; desiccation filter 13; three-way solenoid valve 14;
main capillary tube 15; bypass capillary tube 16; freezing
evaporator 17; refrigerating evaporator 18; 19; water storage
apparatus 20; ice machine 22; ice making box 23; ice detecting
lever 24; ice storage box 25 and ice cubes 26.
DETAILED DESCRIPTION OF THE INVENTION
[0026] The working mode and the each constitutional component of
the multi-temperature control refrigerator comprising an ice
machine, in which the cooling mode is a mixed air-cooling and
direct cooling mode, are described as follows:
[0027] The refrigerator of the present invention comprises a
freezer compartment 1 and a refrigerator compartment 2, wherein an
ice making room is set inside the freezer compartment 1. Said ice
making room is installed with a door 9 so as to prevent the flow of
the refrigerating effect and the tainting by odor. An ice machine
is mounted in the ice making room and an ice storage box is
arranged below said ice machine. Both the freezer compartment and
refrigerator compartment adopt direct cooling mode and an air inlet
6 and an air outlet 7 connected with the ice making room are set in
the space where the evaporator of the freezer compartment is
presented. The ice making room is deep cooled using air-cooling
mode when needed.
[0028] A door that can be open and shut by turning can be mounted
on the air inlet 6 and/or the air outlet 7 of the ice making room
so as to shut said door when the ice making room is used as a
normal space of the freezer compartment. In such case, the freezer
compartment also adopts the direct cooling mode to achieve
freezing. If the ice making room is changed into a deep freezing
room, i.e. no ice machine is installed in the ice making room 3,
said refrigerator is actually a triple-temperature control
refrigerator with two evaporators where the cooling mode is a mixed
air-cooling and direct cooling mode, i.e. the refrigerating effect
of the refrigerator compartment, the freezer compartment and the
ice making room can be controlled separately according to
requirements.
[0029] The direct cooling of the refrigerator compartment of the
refrigerator of the present invention adopts a plate type
evaporator, which sticks to the upper part of the back wall of the
inner liner of the refrigerator compartment by press bonding
process. Refrigeration are achieved by natural convection and when
the temperature in the compartment reaches the preset temperature,
refrigerating temperature control unit will send an impulse signal
to the impulse solenoid valve which takes action to switch off the
refrigeration cycle of the refrigerant.
[0030] Said plate type evaporator sticks to the inner liner of the
refrigerator compartment. The advantages are that the evaporator is
hided so as not to affect the appearance and the refrigeration is
uniform and causes little frostbite to articles, etc.
[0031] The refrigerator compartment adopts plate type evaporator,
which keeps the humidity at a relatively high level in the
compartment.
[0032] Please refer to FIG. 1. FIG. 1(b) illustrates a cutaway view
of the multi-temperature control refrigerator of the present
invention where the cooling mode is a mixed air-cooling and direct
cooling mode. The position of the components and their connecting
means can be viewed clearly in the figure.
[0033] The freezer compartment of the refrigerator of the present
invention also adopts direct cooling mode and one side of the
evaporator also sticks to the inner liner of the freezer
compartment. But, behind the other side of the evaporator there is
a gap, through which the air from the ice making room flows upward,
gets cooled again and enters into the ice making room. The ice
making room adopts air-cooling mode, which makes the cooling speed
of ice making room much faster than that using only direct cooling
mode.
[0034] Thus, the ice making room adopts a mixed air-cooling and
direct cooling mode, which is equivalent to having two controllable
temperature zones.
[0035] The freezer compartment adopts a mixed air-cooling and
direct cooling mode and in order to improve the refrigerating
efficiency of the ice making room, the evaporator of the freezer
compartment is a fin type evaporator. In order to prevent the
inadequacy of the refrigerating effect of the fin type evaporator
when compared with the requirement of the freezer compartment, the
whole or part of the ice making room uses materials that are high
in thermal conductivity as baffle plate, e.g. aluminum. In this
way, the refrigerating effect of the ice making room can be
exchanged through the baffle plate and due to that the ice making
room is preferably set in the upper part of the freezer
compartment, the cold air near the outer wall of the ice making
room goes down and forms a cycle having a heat exchange
process.
[0036] The multi-temperature control function of the present
invention means that the refrigerant flows through the impulse
solenoid valve to the freezer or refrigerator compartment according
to the requirement of refrigerating effect of the freezer or
refrigerator compartment. The temperatures of the two compartments
are detected by the temperature sensing units of the temperature
control apparatus of each compartment and the controller of the
refrigerator controls the action sensor set inside the ice making
room, or connecting the circuit of the ice making room to the main
control circuit of the refrigerator, to sense the working
conditions of the ice machine.
[0037] The working method for the refrigerator of the present
invention is described in the following paragraphs.
[0038] When determining whether the ice making process is to be
carried out or not and if the ice making process is to be
commenced, the evaporator of the freezer compartment is started and
the fan is also started to cool the ice making room quickly to an
ice-making quick-freezing temperature.
[0039] When determining the ice making room is at a
temperature-maintaining state or not and if the temperature doesn't
reach the preset ice-making maintaining temperature, the evaporator
of the freezer compartment is started and the fan is also started
to cool the ice making room quickly to the ice-making maintaining
temperature.
[0040] Because the preset temperature and the maintaining
temperature of the ice making room are lower than the preset
temperature of the freezer compartment, the temperature of the
freezer compartment should be kept lower than the preset
temperature in such circumstance.
[0041] Preferably, the maintaining temperature of the ice making
room is set the same as the preset temperature of the freezer
compartment. When the temperature of the freezer compartment
doesn't reach the preset temperature and needs to be cooled, the
refrigerant enters the main cycle. Because the area of the main
evaporator in the refrigerator compartment is relatively small, the
cold energy released by the evaporator of the refrigerator
compartment is minor and the drop in temperature is very small.
When metal baffle plate is used in the ice making room, the heat in
the ice making room and the freezer compartment is substantially
exchanged.
[0042] In order to improve the ice making efficiency of the ice
making room, i.e. to maintain a lower temperature as long as
possible in the ice making room than in the freezer compartment, a
baffle plate with good thermal insulation property is used between
the ice making room and the freezer compartment and the
quick-freezing temperature and the maintaining temperature of the
ice making room are set distinctively below the preset temperature
of the freezer compartment. In this condition, the ice making room
forms a deep freezing compartment when no ice machine is mounted in
the ice making room.
[0043] When the freezer compartment has reached the preset
temperature and the refrigerator compartment hasn't, the bypass
circuit is turned on. The main evaporator of the refrigerator
compartment of the main circuit, which has a relatively small area
for evaporation, is combined with an additional evaporator of the
refrigerator compartment, which has a relatively larger area for
evaporation, and forms an evaporator of the refrigerator
compartment that has very large evaporation area so as to adjust
the temperature of the refrigerator compartment rapidly.
[0044] The refrigerator of the present invention comprises
compressor, condenser, desiccation filter, capillary tube, freezing
evaporator, freezer compartment, refrigerating evaporator and air
intake tube.
[0045] In the present invention, plate type evaporator is used in
the refrigerator compartment and fin type evaporator is used in the
freezer compartment.
[0046] The mode of the refrigeration system is discussed in the
following paragraphs. The parallel evaporators configuration
(independent-dual cycle) or an additional circuit in the series
connection configuration of the conventional evaporators have been
disclosed in the prior art. The two configurations enable the
separate control of the freezer compartment and the refrigerator
compartment but the irreversible loss of the thermodynamics is huge
and the condensation of moisture will happen on the external
surface of the air intake tube.
[0047] The present invention provides that an evaporator that is
large in area is connected to the bypass circuit of the bypass dual
refrigeration cycle refrigerator as an additional evaporator of the
refrigerator compartment. Hence the area of the evaporator of the
refrigerator compartment is very large and the bypass capillary
tube can adopt a shorter design because even if the flow is large,
the refrigerant will be fully evaporated in the evaporator due to
large area of the evaporator of the refrigerator compartment and
almost no liquid state refrigerant enters the air intake tube. When
the refrigerator compartment doesn't need refrigerating effect and
the freezer compartment needs, the refrigerant circulates in the
main circuit and because the area of the evaporator of the
refrigerator compartment is small, the released refrigerating
effect is small and the drop of the temperature in the refrigerator
compartment is small, too.
[0048] Thus, the refrigerating effect of the refrigerator
compartment is mainly from the bypass circuit and due to that the
bypass capillary tube in the bypass circuit is relatively short and
that the evaporating temperature is high, the irreversible loss of
the thermodynamics is small and the COP of the system is high.
[0049] The dual refrigeration cycle refrigerator of the present
invention comprises compressor 11, condenser 12, desiccation filter
13, three-way solenoid valve 14, main capillary tube 15, bypass
capillary tube 16, freezing evaporator 17, refrigerating evaporator
19 and water storage apparatus 20, wherein an additional
refrigerating evaporator 18 is comprised in the said bypass
circulating circuit. The outlet of the compressor 11 is connected
to the inlet of the condenser 12; the outlet of the condenser 12 is
connected to the inlet of the desiccation filter 13; the outlet of
the desiccation filter 13 is connected to the three-way solenoid
valve 14; one outlet of the three-way solenoid valve 14 is
connected to the inlet of the main capillary tube 15, the other
outlet is connected to the inlet of the bypass capillary tube 16;
The outlet of the main capillary tube 15 is connected to the inlet
of the freezing evaporator 17; The outlet of the bypass capillary
tube 16 is connected to the inlet of the additional refrigerating
evaporator 18; the outlets of the freezing evaporator 17 and the
additional refrigerating evaporator 18 are both connected to the
inlet of the refrigerating evaporator 19; the outlet of the
refrigerating evaporator 19 is connected to the inlet of the water
storage apparatus 20 and; the outlet of the water storage apparatus
20 is connected to one end of the air intake tube and the other end
is connected to the inlet of the compressor 11.
[0050] When compared with single refrigeration cycle system, the
refrigeration system of the present invention is provided with the
following advantages:
[0051] The impact of temperature of the environment to the
temperature in the freezer compartment and in the refrigerator
compartment is avoided and the optimal distribution and utilization
of the energy is achieved.
[0052] Thanks to the dual cycle refrigeration system that can
independently control the temperature of the refrigerator
compartment and the freezer compartment, the freezing ability is
far greater than that of normal refrigerators using single cycle
refrigeration system. The fluctuation range of the temperature in
the refrigerating/freezer compartment in the refrigeration process
of the dual refrigeration cycle refrigerators is far less than that
of the single cycle refrigerators and relatively small fluctuation
range will favor the reservation and preservation of food.
[0053] When designing a dual cycle refrigeration system, a
relatively large refrigerating evaporator can be chosen so as to
satisfy the high temperature requirement and while in a low
environment temperature, the refrigerator can be run normally
without any heating compensation as long as the preset temperature
of the refrigerator compartment is lower than the environment
temperature.
[0054] The present invention provides a bypass dual refrigeration
cycle refrigerator with a variable refrigerating evaporation area.
Researchers believe that the main factors that affect the energy
saving of the bypass dual refrigeration cycle refrigerator with a
variable refrigerating evaporation area are the functional
relations between the load of the refrigerator compartment, the
load of the bypass circuit, the system COP of the main cycle and
the bypass cycle, etc. and the energy saving effects. If such
functional relations are applied, and in the actual operating
conditions of the refrigerators at the present time, the
refrigerator of the present invention saves 12% more energy than
the single cycle refrigerators with evaporators connected in
series.
[0055] The compressor of refrigerator of the present invention is
steam compressor, comprising compressor 11, condenser 12, capillary
tube 15 16, desiccation filter 13, three-way solenoid valve 14,
evaporator 17 18, 19. Said steam compress refrigeration cycle is a
continuous circular process of compressing, condensing, throttling
and evaporating. The refrigerant changes its state periodically
from steam to liquid and from liquid to steam and thus transfer the
heat from inside the refrigerator to the outside so as to achieve
refrigeration.
[0056] In the refrigerator of the present invention adopts the
refrigerant R134a. Other refrigerants in the prior art may also be
used in the embodiments that are not most preferred.
[0057] When designing the refrigerator of the present invention,
the researchers investigate in detail the configuration of the
refrigeration system, the evaporator and the specific configuration
of the evaporator and make a conclusion that due to the
configuration of the arts in existence, the refrigerator of the
present invention has reduced noise and improved thermal
efficiency, specified as follows:
[0058] First, the prior art shows that plate type evaporator
(direct cooling mode) bring down the temperature by the
low-temperature natural convection near its surface and the
advantages are that the humidity and the performance of
preservation is favorable, energy is saved and the effective volume
is larger when volume is the same. Fin type evaporators
(air-cooling mode) force a circulation by blowing forcibly cooled
air through air ducts into refrigerators and the advantages are
automatic defrosting and homogeneous temperature while the
disadvantages are low humidity in the freezer compartment and the
food easily air dried and dehydrated, high energy consuming and low
effective volume.
[0059] The characteristics of the refrigerator of the present
invention are that both freezing and refrigerating adopt direct
cooling mode, the direct cooling in the freezer compartment adopts
fin type evaporator, the deficit of refrigerating effect in the
freezer compartment is remediated by the thermal transfer through
the baffle plate of the ice making room and the ice making room
adopts air-cooling mode. As described before, the refrigerating
effect of the ice making room adopting air-cooling mode can also be
transferred through the baffle plate to cool the freezer
compartment.
[0060] With respect to the characteristics of the present
invention, if conventional fin type evaporator is used in the
freezing room as direct cooling, certain problems will arise. The
researchers of the present invention further investigate the fin
type evaporators and the results show that various factors may
affect the efficiency of the fin type evaporators. Please refer to
FIG. 2(a) to FIG. 2(f).
[0061] The conclusion is that the relative humidity of the air has
great effect on the performance of the evaporator, especially in a
circumstance of high humidity. The efficiency of the evaporator
(.eta..sub.0) and the average heat exchange coefficient on the air
side (K.sub.0) drop abruptly along with the extended operating time
of the evaporator. Thus, the control of the relative humidity of
the air has great effects on the evaporator.
[0062] In addition, the fin pitch also affects the performance of
the evaporator greatly. The performance of the evaporator that has
a wide fin pitch evidently excels that of the evaporator that has a
close fin pitch. When the fin pitch is about 4 mm, the performance
of the evaporator drops sharply. The fin pitch of over 6 mm is
always adopted under a low temperature operating condition. A fin
pitch of 6-8 mm of the evaporator is preferred.
[0063] Whereas the air-cooling mode is characterized as a rapid
refrigeration means, a high humidity in the ice making room may
result in the drop of efficiency of the evaporator. In the light of
the conflict, a fin type evaporator is adopted in the freezer
compartment and parameters relating to the fins of the evaporator
etc. are chosen so that a relatively perfect balance is
achieved.
[0064] In order to select further, the researchers make a selection
as to the shape of the fins of the evaporator. Please refer to
FIGS. 3, 4. The geometry parameters of the three types of the
evaporator are listed as follows.
TABLE-US-00001 Fin types Discrete flat Continuous Spiral fins fins
(1) flat fins (2) (3) Tube arrangement method coaxial staggered
coaxial No. of rows of tubes 7 10 5 No. of layers of tubes 2 2 2
External diameter(mm) 8.5 7.9 9.4 Heat width 260 310 300 exchanger
thickness 62 55 65 dimension(mm) height 220 200 150 Heat exchange
tubes 0.097 0.16 0.085 area on the air fins 0.7 0.9 0.5 side(mm)
total 0.8 1 0.6
[0065] The conclusion shows that the efficiency of evaporator (3)
excels that of the other two evaporators as the mixed air-cooling
and direct cooling mode of the freezer compartment of the present
invention and thus is a preferred embodiment in the present
invention.
[0066] In order that a optimal efficiency is achieved, the freezer
compartment and the refrigerator compartment of the present
invention adopt two different kind of evaporator, wherein:
[0067] Said freezer compartment of the refrigerator adopts fin type
evaporator; the freezer compartment is operated in direct cooling
mode while the refrigeration in the ice making room is achieved by
a forced convection of air in the room by a chilling fan. When the
preset temperature of the ice making room is reached, the chilling
fan stops. If the preset temperature of the freezer compartment
hasn't been reached, the evaporator of the freezer compartment
keeps on working and when the preset temperature is reached in the
freezer compartment, the temperature control unit will send an
impulse signal to the impulse solenoid valve which takes action to
switch off the refrigeration cycle of the refrigerant.
[0068] A heating filament is set on said fin type evaporator. In
case defrosting is needed, the timer controls the heater and the
heater is heated up to melt the ice formed on the fins.
[0069] Said fin type evaporator is installed closely to the liner
of the freezer compartment, in charge of the refrigeration of the
freezer compartment and the ice making room. A clearance is formed
on the other side of the evaporator in the freezer compartment and
the air in the ice making room is circulated and cooled by the
chilling fan. The characteristics of the ice making room are rapid
refrigeration, fast temperature drop rate and that the ice cubes
are transparent and bright.
[0070] Thus, the selection of refrigeration system of the present
invention is completed. Hereinafter the design of the ice making
machine is described.
[0071] The automatic ice making of the refrigerator of the present
invention is to realize in control and structure an integrated ice
making process which the ice making system can accomplish
automatically and cycle, so as to achieve automatic ice making of
the refrigerator. Please refer to FIG. 4 for the process.
1) Ice check: determine whether the ice has been made or not by
temperature. 2) Ice removing: remove the ice from the ice making
box to the ice storage box. 3) Water intake: inject water into the
ice making box by pump or valve. 4) Delay and wait for the changing
of the water in the ice making box into ice.
EMBODIMENTS
Embodiment 1
[0072] Please refer to FIG. 4. The ice machine of the present
invention comprises the following parts: (1) The control box
comprises a motor, a reduction gear, an axis of rotation, and
copper tinsels. The copper tinsels are mounted in the plow grooves
in the body, which is similar to the mechanical timer aforetime.
When the ice machine is electrified, the motor rotates and the
copper tinsels form different connections and disconnections which
form different connections of circuits so as to achieve various
travels of the ice machine. (2) Intermediate connection box, the
main function of which is connecting the control box and the ice
making box. A dual-tinsel temperature controller is mounted on the
body of the box, which controls the ice making time and the heating
time of the heater. (3) The ice making box comprises an ice
detecting lever, an ice removing lever, an ice tray and a heater.
When the ice storage box which is set under the ice machine is full
of ice cubes, the ice cubes push up the ice detecting lever and the
power of the ice machine is cut and the ice machine stops working.
The ice detecting lever may also be used to stop the ice machine
manually. The ice removing lever is an ice separation device which
can be turned. When the ice cubes have been made, the heater is
electrified and starts heating and the ice cubes are detached from
the ice tray. The ice removing lever turns a certain degree to push
the ice cubes out of the ice making box.
Embodiment 2
[0073] As an embodiment of the present invention, a defrosting
process is provided, wherein evaporator, fins and a heating tube is
involved. An electric heating filament is set inside the heating
tube and the space between the heating filament and the heating
tube is filled with insulating material. The form of the heating
tube is determined according to the form of the evaporator, in
which all modes used in the prior art can be adopted in the present
invention.
Embodiment 3
[0074] This embodiment provides that the freezer compartment adopts
a mixed air-cooling and direct cooling mode while the refrigerator
compartment adopts direct cooling mode. FIG. 1 can be referred to
for details.
Embodiment 4
[0075] This embodiment is the same as embodiment 3 provided that in
order to form a lower temperature in the ice making room, the air
inlet and air outlet 6, 7 is mounted with air doors, which can be
opened and closed when necessary.
Embodiment 5
[0076] This embodiment is the same as embodiment 3 provided that
said freezer compartment adopting a mixed air-cooling and direct
cooling mode is mounted with an ice machine. FIG. 1 can be referred
to for details.
Embodiment 6
[0077] This embodiment is the same as embodiment 3 provided that
the heater for defrosting the evaporator in the freezer compartment
is in contact with the water inlet of the ice machine. When it is
detected that the water inlet is jammed due to low temperature, the
heater is started to clear the malfunction of the water inlet.
* * * * *