U.S. patent application number 11/568650 was filed with the patent office on 2008-02-14 for refrigeration control system in combined refrigeration appliances.
This patent application is currently assigned to WHIRLPOOL S.A.. Invention is credited to Marco Eduardo Marques, Moacyr Marangone Mezavila, Fabio Ribeiro Pimentel, Alexandre Pinto Rebello Rucker, Rogerio JR. Rodrigues, Alexandre Cury Schmid.
Application Number | 20080034768 11/568650 |
Document ID | / |
Family ID | 36838566 |
Filed Date | 2008-02-14 |
United States Patent
Application |
20080034768 |
Kind Code |
A1 |
Pimentel; Fabio Ribeiro ; et
al. |
February 14, 2008 |
Refrigeration Control System in Combined Refrigeration
Appliances
Abstract
A refrigeration control system in combined refrigeration
appliances of the type comprising: a refrigerating compartment; a
freezing compartment; a compressor; an evaporator; a refrigerating
compartment fan and a freezing compartment fan; and a control means
to activate and deactivate the compressor and both the
refrigerating compartment fan and the freezing compartment fan as a
function of the activation and deactivation temperatures detected
by the refrigerating compartment temperature sensor and the
freezing compartment temperature sensor. The control means is
operatively associated with the refrigerating compartment fan to
selectively and periodically adjust the speed of the latter, so
that the temperature of the refrigerating compartment reaches a
deactivation value of the refrigerating compartment fan at the same
time in which the temperature of the freezing compartment reaches a
deactivation value of both the freezing compartment fan and the
compressor.
Inventors: |
Pimentel; Fabio Ribeiro;
(Joinville-SC, BR) ; Mezavila; Moacyr Marangone;
(Joinville-Sc, BR) ; Schmid; Alexandre Cury;
(Joinville-Sc, BR) ; Rodrigues; Rogerio JR.;
(Joinville-SC, BR) ; Rebello Rucker; Alexandre Pinto;
(Joinville-SC, BR) ; Marques; Marco Eduardo;
(Joinville-SC, BR) |
Correspondence
Address: |
DARBY & DARBY P.C.
P.O. BOX 770
Church Street Station
New York
NY
10008-0770
US
|
Assignee: |
WHIRLPOOL S.A.
Avenida das Nacoes Unidas, 12995 32 andar - Brooklyn
Novo
Sao Paulo - SP
BR
04578-000
|
Family ID: |
36838566 |
Appl. No.: |
11/568650 |
Filed: |
April 29, 2005 |
PCT Filed: |
April 29, 2005 |
PCT NO: |
PCT/BR05/00066 |
371 Date: |
July 11, 2007 |
Current U.S.
Class: |
62/180 |
Current CPC
Class: |
F25D 2700/12 20130101;
F25D 17/065 20130101; F25D 2400/04 20130101; Y02B 40/32 20130101;
F25D 29/00 20130101; F25B 2600/112 20130101; F25D 2700/122
20130101; F25B 2600/0251 20130101; F25D 2317/0682 20130101; Y02B
40/00 20130101 |
Class at
Publication: |
062/180 |
International
Class: |
F25D 17/00 20060101
F25D017/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 4, 2004 |
BR |
PI 0402013-8 |
Claims
1. A refrigeration control system in combined refrigeration
appliances of the type comprising: a refrigerating compartment
provided with at least one refrigerating compartment temperature
sensor; a freezing compartment provided with a freezing compartment
temperature sensor; a compressors; an evaporator; a refrigerating
compartment fan and a freezing compartment fan to produce
respective forced air flows through the evaporator and through the
refrigerating compartment and the freezing compartment,
respectively,--and a control means to activate and deactivate the
compressor and the refrigerating compartment fan and freezing
compartment fan as a function of the activation and deactivation
temperatures detected by the refrigerating compartment temperature
sensor and the freezing compartment temperature sensor, wherein the
control means is operatively associated with the refrigerating
compartment fan to selectively and periodically adjust the speed of
the latter, so that the temperature of the refrigerating
compartment detected by the refrigerating compartment temperature
sensor reaches a deactivation value of the refrigerating
compartment fan at the same time in which the temperature of the
freezing compartment detected by the freezing compartment
temperature sensor reaches a deactivation value of both the
freezing compartment fan and the compressor, said selective and
periodic adjustment of the speed of the refrigerating compartment
fan occurring whenever the ratio between the cooling detected in
the refrigerating compartment and measured from the activation
temperature and the maximum cooling defined between the activation
and deactivation temperatures of the refrigerating compartment fan
differs by an absolute value higher than a determined balance value
from the ratio between the cooling in the freezing compartment
measured from the activation temperature and the maximum cooling
defined between the activations and deactivation temperatures of
the freezing compartment fan.
2. The refrigeration control system according to claim 1, wherein
the balance value between the cooling ratios detected in the
refrigerating and freezing compartments is defined by a variation
from about 5% to about 20% between said ratios.
3. The refrigeration control system according to claim 2, wherein
the speed of the refrigerating compartment fan is increased when
the cooling ratio in the refrigerating compartment is more than
about 5% to about 20% lower than the cooling ratio in the freezing
compartment and also when the relation between the cooling ratio of
the refrigerating compartment and the cooling ratio of the freezing
compartment is negative.
4. The refrigeration control system according to claim 2, wherein
the speed of the refrigerating compartment fan is reduced when the
cooling ratio in the refrigerating compartment is more than about
5% to about 20% higher than the cooling ratio in the freezing
compartment.
5. The refrigeration control system according to claim 3, wherein
the periodic adjustments in the speed of the refrigerating
compartment fan are effected by speed variations representing a
percentage of the nominal speed of the refrigerating compartment
fan.
6. The refrigeration control system according to claim 5, wherein
the speed variation percentage in each speed variation is of about
10%.
7. The refrigeration control system according to claim 1, wherein
the control means compares the cooling ratios of both the
refrigerating compartment and the freezing compartment at each
period of about one to five minutes, in order to detect the need
for adjusting the speed of the refrigerating compartment fan.
8. The refrigeration control system according to claim 1, wherein
the control means instructs the refrigerating compartment fan to
operate with an initial speed that is equal to the last operating
speed when the deactivation temperature of the refrigerating
compartment fan in the refrigerating compartment has been
reached.
9. The refrigeration control system according to claim 1, wherein
the control means activates the refrigerating compartment fan, even
with the compressor being deactivated, when the temperature sensed
in the interior of the refrigerating compartment reaches a
predetermined temperature limit value higher than the activation
temperature of the refrigerating compartment fan.
10. The refrigeration control system according to claim 9, wherein
the control means reduces the deactivation temperature of the
refrigerating compartment during at least one operating cycle of
the latter, whenever it is activated for at least two consecutive
times, with the temperature of the refrigerating compartment being
situated between the activation temperature of the refrigerating
compartment fan and the predetermined limit value.
11. The refrigeration control system according to claim 1, wherein
the control means is operationally and selectively conducted by the
user to operate in a "vacation mode", according to which the
activation temperatures and the deactivation temperatures of both
the refrigerating compartment fan and the freezing compartment fan
are raised to a less cold condition and the speeds of both the
refrigerating compartment fan and the freezing compartment fan are
set to constant and reduced values.
12. The refrigeration control system according to claim 11, wherein
the "vacation mode" is maintained by the control means until the
occurrence of one of the actions of the user deactivating said mode
in an electronic control panel of the refrigeration appliance and
of opening any one of the two doors of the cabinet.
13. The refrigeration control system according to claim 1, wherein
the control means is operationally and selectively conducted by the
user instructing an electronic control panel of the refrigerating
appliance to work in a "party mode", according to which the
activation and deactivation temperatures of the refrigerating
compartment fan are reduced to a cooler condition; the activation
and deactivation temperatures of the freezing compartment fan are
kept in the operational condition originally selected by the user
for the refrigeration appliance,--the speed of the refrigerating
compartment fan is set to a maximum value; and the speed of the
freezing compartment fan is maintained in a constant and reduced
value.
14. The refrigeration control system according to claim 13, wherein
the "party mode" is maintained by a predetermined period, at the
end of which the refrigeration appliance returns to the operating
mode prior to the activation of the "party mode".
Description
FIELD OF THE INVENTION
[0001] The present invention refers to a refrigeration control
system to be applied to combined refrigeration appliances that
present a refrigerating compartment and a freezing compartment,
each provided with a forced air flow which is refrigerated in an
evaporator and blown by a respective fan.
PRIOR ART
[0002] There are well known in the art the combined refrigeration
appliances in which each of the refrigerating and freezing
compartments is provided with a temperature sensor operatively
associated with an electronic control module or means which is
designed to command the activation of the fans of said compartments
and of the compressor of the refrigeration circuit of the
refrigeration appliance. In said combined appliances, the
refrigerating compartment temperature sensor informs the control
means about the activation and deactivation temperatures of the
refrigerating compartment fan, in order to vary the cool air supply
to the compartment as a function of the temperature detected by the
refrigerating compartment temperature sensor. On the other hand,
the freezing compartment temperature sensor informs the control
means about the activation and deactivation temperatures of the
freezing compartment fan and of the compressor. Such refrigeration
control system allows the refrigerating compartment fan to operate
independently of the freezing compartment fan, according to the
temperature signals that the refrigerating compartment temperature
sensor sends to the control means. Depending on how often the
refrigerating compartment is used, loss of synchrony in the
operation of both fans can usually occur, since the refrigerating
compartment fan can be activated by the control means as a function
of the temperature condition detected by the refrigerating
compartment temperature sensor, even with both the compressor and
the freezing compartment fan being deactivated. In terms of
operation of the refrigeration appliance, the operation mentioned
above is not prejudicial, since the activation of the refrigerating
compartment fan without activation of the compressor causes the
latter to be reactivated more rapidly, promoting cooling of the
refrigerating compartment.
[0003] Nevertheless, in terms of reduction of energy consumption,
the above operation is not desired, since it causes irregular
operating cycles of the compressor. To reduce energy consumption,
the more adequate operation is the one according to which the
compressor operates in regular cycles, with the activation and
deactivation times being cyclically repeated.
[0004] Another aspect regarding the known refrigeration control
systems is the fact that they do not allow the occurrence of a
joint operation of the compressor and fans which is adequate to a
special and temporary usage pattern of the refrigeration appliance
as a whole or of the refrigerating compartment only. In the known
appliances, the designed adjustment is limited to the setting of
the operational temperature ranges of the refrigeration
appliance.
OBJECTS OF THE INVENTION
[0005] As a function of the inconveniences mentioned above, it is
an object of the present invention to provide a refrigeration
control system in combined refrigeration appliances of the type
considered herein, which leads to a synchronized operation of the
fans of the refrigerating and freezing compartments, in order to
minimize the occurrences of activation of the refrigerating
compartment fan while the compressor fan is deactivated.
[0006] It is a further object of the present invention to provide a
refrigeration control system as described above, which allows the
user to set the operation of the compressor and of the fans to a
special reduced and temporary usage pattern of the combined
refrigeration appliance.
[0007] It is still a further object of the present invention to
provide a refrigeration control system as described above, which
allows the user to set the operation and the speed of the
refrigerating compartment fan to a special intense and temporary
usage pattern of the refrigerating compartment.
SUMMARY OF THE INVENTION
[0008] Aiming at attaining the objects mentioned above, the present
invention provides a refrigeration control system for combined
refrigeration appliances of the type comprising: a refrigerating
compartment provided with at least one refrigerating compartment
temperature sensor; a freezing compartment provided with a freezing
compartment temperature sensor; a compressor; an evaporator; a
refrigerating compartment fan and a freezing compartment fan to
produce respective forced air flows through the evaporator and
through the refrigerating compartment and the freezing compartment,
respectively; and a control means to activate and deactivate the
compressor and the refrigerating compartment and freezing
compartment fans as a function of the activation and deactivation
temperatures detected by the refrigerating compartment temperature
sensor and the freezing compartment temperature sensor.
[0009] According to the invention, the control means is operatively
associated with the refrigerating compartment fan to selectively
and periodically adjust the speed of the latter, so that the
temperature of refrigerating compartment, detected by the
refrigerating compartment temperature sensor, reaches deactivation
value of the refrigerating compartment fan at the same time in
which the temperature of the freezing compartment, detected by the
freezing compartment temperature sensor, reaches a deactivation
value of both the freezing compartment fan and the compressor.
[0010] With the construction above, the control means verifies,
periodically, the cooling degree reached in both the refrigerating
and freezing compartments, verifying whether the cooling speed of
the refrigerating compartment is faster or slower than the cooling
speed of the freezing compartment. Upon being detected a certain
difference in the cooling progress between both compartments, the
refrigerating compartment fan has its speed raised or reduced so as
to approximate the cooling degree of the refrigerating compartment
to the cooling degree already reached in the freezing compartment,
aiming at obtaining the completion of both refrigeration operations
at the same instant and to allow the simultaneous deactivation of
both fans and of the compressor.
[0011] The increases and reductions of the speed of the
refrigerating compartment fan are preferably determined by a
nominal speed percentage value of said fan, allowing the periodic
verifications of the control means to lead to a progressive
approximation of the two cooling degrees of the refrigerating
compartment and the freezing compartment.
[0012] The control means of the present invention further allows
the user to instruct the refrigeration appliance to operate in a
"vacation mode", according to which the operational temperature
ranges of the refrigerating and freezing compartments are reduced
to a less cool condition and the speeds of the refrigerating
compartment and freezing compartment fans are set to constant low
values.
[0013] Still according to the other aspect of the invention, the
control means is constructed to allow the refrigerating appliance
to selectively operate in a "party mode", according to which the
operational temperature range is adjusted to its cooler value and
the speed of the refrigerating compartment fan is set to a constant
maximum value.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The invention will be described below with reference to the
enclosed drawings, given by way of example of possible embodiments
of the invention and in which:
[0015] FIG. 1 is a schematic median vertical sectional view of a
combined refrigeration appliance provided with the control system
of the present invention; and
[0016] FIGS. 2 and 2a illustrate, jointly, a block diagram showing
the processing steps which are carried out by the control means to
effect the settings in the operation of the refrigeration
appliance.
DETAILED DESCRIPTION OF THE INVENTION
[0017] As mentioned above, the present refrigeration control system
is applied to a combined refrigeration appliance whose cabinet 10
defines, internally, a refrigerating compartment R and a freezing
compartment F which are respectively closed by front doors 11, 12.
In the interior of at least one of the refrigerating compartment R
and freezing compartment F is provided an evaporator 20 which in
the illustrated embodiment is positioned in the internal rear
region of the freezing compartment F. The refrigerating compartment
R is provided with a refrigerating compartment temperature sensor
Sr and the freezing compartment with a freezing compartment
temperature sensor Sf, said temperature sensors being operatively
associated with a control means 30 adequately secured to the
cabinet 10 usually in the lower rear portion of the latter.
[0018] Cabinet 10 further houses a refrigerating compartment fan 40
and a freezing compartment fan 50 which are positioned and
dimensioned to produce respective forced air flows through the
evaporator 20 and through the refrigerating and freezing
compartments R and F, respectively. The refrigerating compartment
and freezing compartment fans 40 and 50 are operatively associated
with the control means 30, which is also operatively coupled to a
compressor 60 of the refrigeration system of the refrigeration
appliance. The construction defined above allows the control means
30 to activate and deactivate the compressor 60 and the
refrigerating compartment and freezing compartment fans 40 and 50
as a function of the activation and deactivation temperatures
detected by the refrigerating compartment and freezing compartment
sensors Sr and Sf.
[0019] According to the invention, the control means 30 is
operatively associated with the refrigerating compartment fan 40 to
adjust, selectively and periodically, the speed of the latter, in
order to make the temperature of the refrigerating compartment R,
detected by the refrigerating compartment temperature sensor Sr, to
reach a deactivation value of the refrigerating compartment fan 40
substantially at the same time in which the temperature of the
freezing compartment F, detected by the freezing compartment
temperature sensor Sf, reaches a deactivation value of the freezing
compartment fan 50 and of the compressor 60.
[0020] The concept used in the present invention is mainly based on
the periodic adjustment of the speed of the refrigerating
compartment fan 40, in order to make the cooling of the
refrigerating compartment R to end at the same time of the cooling
of the freezing compartment F, whereby the respective refrigerating
compartment and freezing compartment temperature sensors Sr and Sf
will simultaneously inform the control means 30 that the
deactivation temperatures of both the refrigerating compartment fan
40 and the freezing compartment fan 50 jointly with the
deactivation of compressor 60 have been reached. The balance in the
cooling time of the refrigerating and freezing compartments R and F
leads to a synchronized operation of both the refrigerating
compartment fan 40 and the freezing compartment fan 50 with the
compressor 60 consequently operating in periodic regular cycles,
allowing an optimized energy consumption to be obtained in terms of
compressor operation.
[0021] Particularly, the selective and periodic adjustment of the
speed of the refrigerating compartment fan 40 occurs whenever the
ratio between the cooling detected in the refrigerating compartment
R and measured from the activation temperature and the maximum
cooling defined between the activation and deactivation
temperatures of the refrigerating compartment fan 40 differs by an
absolute value higher than a determined balance value from the
ratio, between the cooling of the freezing compartment F measured
from the activation temperature and the maximum cooling defined
between the activation and deactivation temperatures of the
freezing compartment fan 50.
[0022] Said balance value between the cooling ratios detected in
the refrigerating and freezing compartments R and F can be defined
by a variation from about 5% to about 20% between said ratios,
i.e., while the variation between the cooling ratios remains within
about higher or lower values from about 5% to about 20%, the
control means 30 will maintain the speed of the refrigerating
compartment fan 40 unaltered, modifying said speed to higher or
lower values when said difference between both cooling ratios
surpasses the exemplary balance value of about 5% to about 20%.
[0023] According to the invention, the speed of the refrigerating
compartment fan 40 is increased when the cooling ratio in the
refrigerating compartment R is more than about 5% to about 20%
lower than the cooling ratio of the freezing compartment F and also
when the relation between the cooling ratio of the refrigerating
compartment R and the cooling ratio of the freezing compartment F
is negative. On the other hand, the speed of the refrigerating
compartment fan 40 is reduced when the cooling ratio of the
refrigerating compartment R is more than about 5% to about 20%
higher than the cooling ratio of the freezing compartment F.
[0024] The periodic speed settings of the refrigerating compartment
fan 40 are achieved, when necessary, by speed variations which
represent a percentage, for example of about 10% the nominal speed
of the refrigerating compartment fan 40.
[0025] Considering that the control means 30 can be constructed to
compare the cooling ratios of both the refrigerating compartment R
and the freezing compartment F in time intervals of five minutes
for example, the need for adjusting the speed of the refrigerating
compartment fan 40 can be checked in said time intervals during
each operating period of the compressor, allowing that at each
check the speed of the refrigerating compartment fan 40 can be
varied by the necessary increase or reduction, in order to
progressively approximate the cooling ratio of the refrigerating
compartment R to the cooling ratio of the freezing compartment
F.
[0026] According to one way of carrying out the present invention,
the setting of the speed of the refrigerating compartment fan 40 is
effected by the control means 30 from a calculation using the
following mathematical expression: dF dR = Tsf - Taf Tdf - Taf Tsr
- Tar Tdr - Tar ##EQU1##
[0027] In the mathematical expression above, dF is the cooling
ratio of the freezing compartment F, while dR is the cooling ratio
of the refrigerating compartment R. The cooling ratio dF of the
freezing compartment F is obtained by dividing the difference
between the activation temperature Taf of the freezing compartment
fan 50 in the freezing compartment F and the sensed temperature Tsf
in said freezing compartment F by the difference between the
activation Taf and deactivation Tdf temperatures of the freezing
compartment fan 50 in said freezing compartment F. Similarly, the
cooling ratio dR of the refrigerating compartment R is obtained by
dividing the difference between the activation temperature Tar of
the refrigerating compartment fan 40 in the refrigerating
compartment R and the sensed temperature Tsr in said refrigerating
compartment R by the difference between the activation Tar and
deactivation Tdr temperatures in the refrigerating compartment fan
40.
[0028] Thus, the numerator of said mathematical expression shows
how much the freezing compartment F has been cooled and how much it
is close to reach the deactivation temperature Tdf in which the
compressor 60 and the freezing compartment fan 50 will be
deactivated.
[0029] In an analogous way, the denominator of said mathematical
expression shows how much the refrigerating compartment R has been
cooled and how much it is close to reach the deactivation
temperature Tdr in which the refrigerating compartment fan 40 is
deactivated.
[0030] The quotient of the cooling ratios dR, dF gives a relative
comparison of said compartments, informing how much each
compartment has been cooled during its cooling process until the
deactivation temperatures Tdr and Tdf of the respective
refrigerating compartment fan 40 and freezing compartment fan 50
have been reached.
[0031] The control means 30 is preferably programmed to evaluate
the expression above at each operating time period of about 1-5
minutes, commanding the adjustment of the speed of the
refrigerating compartment fan 40 in the same frequency and
according to the table given below, considering the balance value
as being for example 10%: TABLE-US-00001 dF/dR <= 0 increases
the speed 0 < dF/dR <= 0.9 reduces the speed 0.9 < dF/dR
< 1.1 maintains the speed dF/dR >= 1.1 increases the speed
dF/dR = div/0 maintains the speed
[0032] At the end of the operating time of one cycle of the
compressor 60, the control means 30 records the speed of the
refrigerating compartment fan 40 and uses it as the initial speed
in the next operating cycle of the compressor 60. Thus, a transient
situation persists in the first cycles until the control means 30
finds the adequate initial speed for the synchronization of the
operating cycles of the refrigerating 40 and freezing compartment
fans. From this moment on, the permanent regime is established and
the cyclic operation, in the ideal conditions to reduce energy
consumption, is repeated.
[0033] Obviously, events such as door opening and storage or
removal of load in relation to the refrigeration appliance will
tend to alter the permanent regime state and/or make the
refrigerating compartment fan 40 be activated in the periods in
which the compressor 60 is deactivated. These events characterized
by a substantial temperature rise of the refrigerating compartment
temperature sensor Sr cannot be disregarded by the control system,
which otherwise could greatly upset the user.
[0034] Thus, the control system is programmed to activate the
refrigerating compartment fan 40 even with the compressor 60 being
deactivated, when the temperature of the refrigerating compartment
R reaches a predetermined limit value that is above the activation
temperature Tar of the refrigerating compartment fan 40. Thus, the
control system gives priority to the performance of the
refrigerating compartment in detriment of the synchronization of
the fans, when such synchronization is capable of producing a
prejudicial unbalance in the operational temperature of the
refrigerating compartment R.
[0035] Another important aspect of the present control system is
the protection which allows the temperature of the refrigerating
compartment R to remain the more stable possible. Some "loss of
control" in the temperature of the refrigerating compartment R can
occur when the refrigerating compartment fan 40 is prevented from
being activated and the temperature Tsr detected by the
refrigerating compartment temperature sensor Sr is above the
activation temperature Tar of said refrigerating compartment fan
40, but below the predetermined limit value from which the
refrigerating compartment fan 40 is activated independently of the
state in which the compressor 60 is found. Such "loss of control"
is characterized by the elevation of the medium temperature of the
refrigerating compartment R when, in some circumstances, the
refrigerating compartment fan 40 is activated, in the start of the
activation cycle of the compressor, by several successive cycles
above its activation temperature Tar.
[0036] In order to provide a protection against this undesirable
situation, the control system is programmed to reduce the
deactivation temperature Tdr of the refrigerating compartment fan
40 during at least one operating cycle of the latter, whenever it
is activated at least two consecutive times and with the
temperature of the refrigerating compartment R situated between the
activation temperature Tar of the refrigerating compartment fan 40
and the predetermined limit value.
[0037] The present refrigeration control system further allows the
user to adjust the operation of the fans and consequently of the
compressor 60 to a reduced and temporary special usage pattern
which commonly occurs in periods of vacation or trips during which
the refrigeration appliance operates without any modification
occurring in its inner load or without any of its doors being
opened.
[0038] Thus, the control means 30 is constructed so that it can be
optionally and selectively conducted to operate in a "vacation"
mode, according to which the activation temperatures Tar, Taf and
deactivation temperatures Tdr and Tdf of the refrigerating
compartment fan 40 and the freezing compartment fan 50 are raised
to a "less cool" condition and the speed of the said refrigerating
compartment fan 40 and freezing compartment fan 50 are set to
constant reduced values. The benefit to the user is translated in
energy saving during the time in which the "vacation" function or
mode is activated. The user activates this function through the
electronic control panel and the duration period is indefinite,
lasting until the function is deactivated or until one of the doors
11 or 12 of the refrigeration appliance is opened.
[0039] In accordance with one more aspect of the invention, the
control means 30 can be optionally and selectively conducted, by
the user instructing an electronic control panel of the
refrigeration appliance to work in a "party" mode, in which: the
activation temperature Tar and deactivation temperature Tdr of the
refrigerating compartment fan 40 are reduced to a cooler condition;
the activation temperature Taf and deactivation temperature Tdf of
the freezing compartment fan 50 are maintained in the operating
condition originally selected by the user for the refrigeration
appliance; the speed of the refrigerating compartment fan 40 is set
to a maximum value; and the speed of the freezing compartment fan
50 is maintained in a constant reduced value.
[0040] The actions resulting from the party mode lead to a total
priority of the refrigerating compartment R in detriment of the
freezing compartment F. The freezing compartment F remains
operating normally, according to the operational temperature
selected by the user, it being understood that its operating
condition is not adequate to great demands in relation to door
openings and relevant loadings.
[0041] The refrigerating compartment R, on its turn, operates in
the most favorable condition, to positively and rapidly respond to
great demands, keeping the stored foods and beverages in adequate
conditions and propitiating a more efficient cooling of the load to
be replaced.
[0042] The user activates the party mode through the electronic
control panel of the refrigeration appliance, and the deactivation
occurs automatically after a determined period of time has elapsed,
for example six hours, after which the refrigeration appliance will
return completely to its operating mode being used before the
activation of the party mode. FIGS. 2 and 2a of the appended
drawings illustrate, jointly and in block diagrams, the operation
of the refrigeration control system of a combined refrigeration
appliance of the type illustrated in FIG. 1 described above.
[0043] As already mentioned, the control means 30 is operatively
associated with the refrigerating compartment fan 40 and freezing
compartment fan 50 and to the refrigerating compartment and
freezing compartment temperature sensors Sr and Sf and also with
the compressor 60, in order to drive said fans and the compressor
according to the temperature parameters informed to the control
means 30 through the refrigerating compartment and freezing
compartment temperature sensors Sr and Sf. The control means 30 is
provided with a clock of adequate construction (not illustrated)
and is also operatively associated with a control panel (not
illustrated) of the refrigeration appliance which functions as an
interface between said appliance and the user, so that the latter
can modify or set the operational characteristics of the
refrigeration appliance.
[0044] In the block diagrams of FIGS. 2 and 2a, the references in
alphabetic characters are the ones already used during the present
description, it being only necessary to further consider the
following additional references: Counter Tout=counter for the
number of times the compressor is activated with Tsr>Tar;
Tout=temperature to be diminished from the original value of the
temperature deactivation of the refrigerating compartment fan 40
Tdf; T=temperature difference between Tsr and Tar, above which the
refrigerating compartment fan 40 turns on, even if the compressor
60 is switched off; and ta=time interval between successive speed
settings of the refrigerating compartment fan 40.
[0045] As illustrated in FIG. 2, the control system is initiated
from a condition in which the compressor 60 and the refrigerating
compartment and freezing compartment fans 40, 50 are switched off
with the counter of the number of times the compressor is activated
with Tsr>Tar indicating a null value of times in which the
appliance has been driven in this particular condition.
[0046] Once the initial conditions cited above have been
established, the control means 30 promotes reading of the
temperatures of the freezing compartment sensor Sf and
refrigerating compartment sensor Sr and subsequently compares the
value of the temperature Tsr sensed in the refrigerating
compartment R with the sum of the activation temperature Tar of the
refrigerating compartment fan 40 with the temperature difference
between the temperature values Tsr sensed in the refrigerating
compartment R and the activation temperature Tar of the
refrigerating compartment fan 40. In case the comparison above
indicates a temperature Tsr higher than or equal to said sum, the
control means 30 instructs the refrigerating compartment and
freezing compartment fans 40, 50 to operate, maintaining the
compressor still switched off. In this step of the control system,
the working speed of the refrigerating compartment fan 40 is
established in the value of the last speed applied thereto or in
the value of a default speed.
[0047] Once the speed of the refrigerating compartment fan 40 has
been established, the control means 30 compares the values of the
temperature Tsf of the freezing compartment F with the activation
temperature Taf of the freezing compartment fan 50. If the
temperature Tsf of the freezing compartment F is superior or equal
to the value of said activation temperature Taf, the control means
30 instructs both the compressor 60 and the freezing compartment
fan 50 to operate. If the temperature Tsf of the freezing
compartment F is lower than the activation temperature Taf of the
freezing compartment fan 50, the system returns to the step of
comparing the values between the temperature Tsr of the
refrigerating compartment R and the sum of the activation
temperatures Tar of the refrigerating compartment fan 40 and the
difference of the temperatures Tfr and Tar. In case the temperature
Tsr of the refrigerating compartment R is inferior to said sum of
the activation temperature Tar with the difference between the
temperatures Tsr and Tar, the control system further instructs the
control means 30 to pass to the step of comparing the temperatures
Tsf of the freezing compartment F and the activation temperature
Taf of the freezing compartment fan 50. Once the compressor 60 and
the freezing compartment fan 50 are switched on, the control means
30 checks whether the temperature Tsr of the refrigerating
compartment R is superior or equal to the activation temperature
Tar of the refrigerating compartment R. In case Tsr is superior or
equal to Tar, the control means 30 checks whether the number of
times in which the compressor is driven with Tsr>=Tar is higher
than or equal to 2. If this situation occurs, the control means
will keep the deactivation temperature Tdr of the refrigerating
compartment fan 40 equal to the original deactivation temperature
of said refrigerating compartment fan 40. In this case, it is not
necessary to vary the deactivation temperature Tdr of the
refrigerating compartment fan 40, being zero the temperature to be
diminished from the original value of said deactivation temperature
Tdr, whereby the equation Tdr=Tdr-Tout results in temperature Tdr
being adjusted by the control means 30 to be equal to the
temperature Tdr originally set by the user in the control panel,
for the operation of the refrigeration appliance.
[0048] Once the conditions above have been observed, the control
means 30 switches on the refrigerating compartment fan 40.
[0049] On the other hand, if the control means 30 verifies the
temperature Tsr of the refrigerating compartment R is lower than
the deactivation temperature Tdr of the refrigerating compartment
fan 40, the control means 30 switches off the refrigerating
compartment fan 40, and the control system returns to the previous
step, in which the control means 30 instructs both the compressor
30 and the freezing compartment fan 50 to operate. If the
temperature Tsr is higher than or equal to Tar, the control means
30 keeps the deactivation temperature Tdr of the refrigerating
compartment fan 40 equal to the temperature Tdr originally
established or set for the operation of the refrigeration
appliance, and the control means 30 then instructs the
refrigerating compartment fan 40 to operate.
[0050] Upon occurring the operational situation described above,
the control means 30 instructs the refrigerating compartment fan 40
to operate in the speed previously applied thereto or in the
default speed established in the project. Then, the control means
30 verifies the dF/dR relation between the cooling ratios of the
freezing compartment F and of the refrigerating compartment R,
respectively. The control means 30 verifies the different
conditions illustrated in the median block of FIG. 2a. Thus,
considering the exemplary value of 10% for the balance value for
said cooling ratios, if the dF/dR ratio is zero, the control means
30 raises the speed of the refrigerating compartment fan 40. If the
dF/dR ratio is higher than zero and lower than or equal to 0.9, the
control means 30 reduces the speed of the refrigerating compartment
fan 40. If the dF/dR ratio is higher than 0.9 and lower than 1.1,
the control means 30 maintains the speed of the refrigerating
compartment fan 40 unaltered. If the dF/dR ratio is superior or
equal to 1.1, the control means 30 raises the speed of said
refrigerating compartment fan 40 and if said ratio is equal to the
ratio resulting from a division by zero, the control means 30 will
also maintain the speed of the refrigerating compartment fan 40
unaltered.
[0051] The control means 30 then verifies, in a subsequent step,
whether the temperature Tsf of the freezing compartment F is lower
than the deactivation temperature Tdf of the freezing compartment
fan 50. In case said operational condition occurs, the control
means 30 switches off the compressor 60 and checks whether the
temperature Tsr of the refrigerating compartment R is superior or
equal to the sum of the activation temperature Tar of the
refrigerating compartment fan 40 with the difference between the
temperatures Tsr and Tar. In case such condition does not occur,
the control means 30 switches off the freezing compartment fan 50
and the refrigerating compartment fan 40, maintaining the
deactivation temperature Tdr of the refrigerating compartment fan
40 equal to the temperature Tdr originally set for the
refrigeration appliance and returns to the beginning of the control
system operation.
[0052] In case the control means 30 verifies the occurrence of the
Tsr>=Tar+T condition, it drives the freezing compartment fan 50
and refrigerating compartment fan 40, turning off the compressor 60
and returning to the step of the control process in which the
control means 30 restores the speed of the refrigerating
compartment fan 40, keeping it equal to a value previously used or
applying the default speed designed for the system.
[0053] On the other hand, in case the control means 30 verifies
that the temperature Tsf of the freezing compartment F is higher
than or equal to the deactivation temperature Tdf of the freezing
compartment fan 50, it switches off the refrigerating compartment
fan 40 and checks whether the temperature Tsr of the refrigerating
compartment R is superior or equal to the activation temperature
Tar of the refrigerating compartment fan 40. If the Tsr<Tar
condition occurs, the control means 30 returns the system to the
condition in which it promotes the operation of the refrigerating
compartment fan 40, either in the previous speed or in the default
speed. In the hypothesis the refrigerating compartment fan 40 is
switched off and Tsr<Tar, the control means 30 verifies whether
the temperature of the refrigerating compartment R is lower than
the deactivation temperature Tde of the refrigerating compartment
fan 40. If this condition occurs, the control means 30 switches off
both the refrigerating 40 and the freezing 50 fans and switches off
the compressor 60, maintaining the deactivation temperature Tdr of
the refrigerating compartment fan 40 equal to the original
deactivation temperature Tdr of said fan, returning the control
system to the step in which the control means 30 verifies whether
the temperature Tsf of the freezing compartment F is lower than the
deactivation temperature Tdf of the freezing compartment fan 50. If
the control means detects a temperature Tsr of the refrigerating
compartment R higher than or equal to the deactivation temperature
Tdr of the refrigerating compartment fan 40, it will further verify
whether the refrigerating compartment fan 40 is switched on. If
said refrigerating compartment fan 40 is switched off, the control
means 30 returns the process to said step of comparing the
temperature Tsf of the freezing compartment F with the deactivation
temperature Tdf of the freezing compartment fan 50. If the
refrigerating compartment fan 40 is on, the control means 30
verifies whether the speed setting time of the refrigerating
compartment fan 40 is superior or equal to the time interval Ta
between successive speeds settings of said fan.
[0054] In case the comparison of said times does not occur, the
control means 30 returns the control system to the step of
comparing the temperature Tsf of the freezing compartment F with
the deactivation temperature Tdf of the freezing compartment fan
50. If said speed setting time/time interval Ta relation occurs,
the control means 30 returns the system to the step of verifying
the relation between the cooling ratio Tf of the freezing
compartment F and the cooling ratio Tr of the refrigerating
compartment R.
[0055] While only one way of carrying out the invention has been
described and illustrated herein, it should be understood that
alterations in the form and arrangement of the component parts of
the control system could be made, without departing from the
protective scope defined by the appended claims.
* * * * *