U.S. patent application number 12/878732 was filed with the patent office on 2011-03-17 for device for supplying warm water and method thereof.
This patent application is currently assigned to WOONGJIN COWAY CO., LTD.. Invention is credited to Tae Kyung KANG, Jeong Yeon KIM, Jong Min KIM.
Application Number | 20110061608 12/878732 |
Document ID | / |
Family ID | 43127360 |
Filed Date | 2011-03-17 |
United States Patent
Application |
20110061608 |
Kind Code |
A1 |
KIM; Jeong Yeon ; et
al. |
March 17, 2011 |
DEVICE FOR SUPPLYING WARM WATER AND METHOD THEREOF
Abstract
Provided is a device for supplying warm water and a method
thereof. The device for supplying warm water includes a first
heater configured to have a first set capacity and heating received
water, a second heater configured to have a second set capacity
greater than the first set capacity and heating received water, and
a control part calculating heater driving cycles of the first
heater and the second heater according to a set water temperature,
and driving the first heater and the second heater according to the
heater driving cycles. The control part calculates the heater
driving cycle of the first heater by using a phase control method,
and calculates the heater driving cycle of the second heater by
using a zero-crossing control method.
Inventors: |
KIM; Jeong Yeon; (Seoul,
KR) ; KIM; Jong Min; ( Seoul, KR) ; KANG; Tae
Kyung; (Seoul, KR) |
Assignee: |
WOONGJIN COWAY CO., LTD.
Choongcheongnam-do
KR
|
Family ID: |
43127360 |
Appl. No.: |
12/878732 |
Filed: |
September 9, 2010 |
Current U.S.
Class: |
122/14.1 |
Current CPC
Class: |
H02M 2005/2937 20130101;
F24D 19/1051 20130101; F24H 1/101 20130101; H02M 1/083 20130101;
H02M 1/12 20130101; H05B 1/0283 20130101 |
Class at
Publication: |
122/14.1 |
International
Class: |
F24H 9/20 20060101
F24H009/20 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 11, 2009 |
KR |
10-2009-0085959 |
Jun 15, 2010 |
KR |
10-2010-0056449 |
Claims
1. A device for supplying warm water, the device comprising: a
first heater configured to have a first set capacity and heating
received water; a second heater configured to have a second set
capacity greater than the first set capacity and heating received
water; and a control part calculating heater driving cycles of the
first heater and the second heater according to a set water
temperature, and driving the first heater and the second heater
according to the heater driving cycles, wherein the control part
calculates the heater driving cycle of the first heater by using a
phase control method, and calculates the heater driving cycle of
the second heater by using a zero-crossing control method.
2. The device of claim 1, wherein the control part determines
whether a temperature of water received in the first heater and the
second heater is lower than the set water temperature, and
calculates the heater driving cycles when the temperature of the
received water is lower than the set water temperature.
3. The device of claim 1, wherein the first set capacity is greater
than zero and lower than 550 W, and the second set capacity is
equal to or greater than 550 W and lower than 1250 W.
4. A method of supplying warm water, the method comprising:
preparing a first heater having a first set capacity, and a second
heater having a second set capacity greater than the first set
capacity; calculating a heater driving cycle of the first heater
according to a set water temperature by using a phase control
method, while calculating a heater driving cycle of the second
heater according to the set water temperature by using a
zero-crossing control method; and driving the first heater and the
second heater according to the heater driving cycles to heat water
received in the first heater and the second heater, and discharging
the heated water.
5. The method of claim 4, further comprising determining whether a
temperature of the water received in the first heater and the
second heater is lower than the set water temperature, wherein the
heater driving cycles are calculated when the temperature of the
water is lower than the set water temperature.
6. The method of claim 4, wherein the first set capacity is greater
than zero and lower than 550 W, and the second set capacity is
equal to or greater than 550 W and lower than 1250 W.
7. A method of supplying warm water, the method comprising: a
preparation operation in which a first heater having a first set
capacity, and a second heater having a second set capacity greater
than the first set capacity are prepared; an operation setting
operation in which a set water temperature and set water quantity
are input; an operation preparation operation in which water is
received in an amount equal to or greater than the set water
quantity, it is determined whether to perform heating according to
a temperature of the received water, and quantity of heat required
for the heating is calculated; and a control operation in which,
when the heating is required, at least one of the first heater and
the second heater is selected as a heater to be driven according to
the required quantity of heat, a heater driving cycle of the
selected heater is calculated, and the selected heater is driven
according to the heater driving cycle, wherein in the control
operation, a heater driving cycle of the first heater is calculated
by using a phase control method, and a heater driving cycle of the
second heater is calculated by using a zero-crossing control
method.
8. The method of claim 7, wherein the control operation comprises a
first control operation in which the first heater is selected as a
heater to be driven when the required quantity of heat is less than
the first set capacity, and the heater driving cycle of the first
heater is calculated by using the phase control method to thereby
drive the first heater.
9. The method of claim 7, wherein the control operation comprises a
second control operation in which the second heater is selected as
a heater to be driven when the required quantity of heat is equal
to or greater than the first set capacity and lower than the second
set capacity, and the heater driving cycle of the second heater is
calculated by using the zero-crossing control method to thereby
drive the second heater.
10. The method of claim 7, wherein the control operation comprises
a third control operation in which the first heater and the second
heater are selected as heaters to be driven when the required
quantity of heat is equal to or greater than the second set
capacity, the heater driving cycle of the first heater is
calculated by using the phase control method to thereby drive the
first heater, and the heater driving cycle of the second heater is
calculated by using the zero-crossing control method to thereby
drive the second heater.
11. The method of claim 10, wherein, in the third control
operation, the heater driving cycle of the second heater is
calculated such that the second heater is driven by the second set
capacity, and the heater driving cycle of the first heater is
calculated such that the first heater is driven by a capacity
obtained by subtracting the second set capacity from the required
quantity of heat.
12. The method of claim 7, wherein the operation preparation
operation comprises: receiving water in an amount equal to or
greater than the set water quantity; measuring a water temperature
of the received water; calculating the required quantity of heat
for heating when the measured water temperature is lower than the
set water temperature; and discharging water when the measured
water temperature is equal to or higher than a preset temperature,
and going into a standby state, wherein the preset temperature is
equal to or higher than the set water temperature, and the
measuring of the water temperature is performed again when the
water temperature is equal to or higher than the set water
temperature and lower than the preset temperature.
13. The method of claim 7, wherein the first set capacity is
greater than zero and lower than 550 W, and the second set capacity
is equal to or greater than 550 W and lower than 1250 W.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priorities of Korean patent
application No. 10-2009-0085959 filed on Sep. 11, 2009 and Korean
patent application No. 10-2010-0056449 filed on Jun. 15, 2010 in
the Korean Intellectual Property Office, the disclosure of which is
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a device for supplying warm
water and a method thereof, and more particularly, to a device for
supplying warm water (hereinafter also "warm water supply device)
and a method thereof, capable of instantaneously heating water for
a home bidet.
[0004] 2. Description of the Related Art
[0005] A warm water supply device, used in a bidet for home use, is
classified into a water tank type that includes a heater installed
inside a water tank, and an instantaneous heating type that heats
water using a heater whenever necessary.
[0006] The water-tank type warm water supply device includes a
heater disposed inside a water tank for storing warm water, and
maintains the water temperature of the water tank at a set
temperature at all times regardless of whether or not a bidet is in
use. Thus, the water-tank type warm water supply device requires a
large amount of standby power and space.
[0007] Recently, the instantaneous heating type warm water supply
device has come into widespread use. When a user makes a request
for the use of a bidet, this type of warm water supply device heats
water, being discharged through an outlet, by using a heater.
[0008] To ensure the stable operation of such an instantaneous
heating type water supply device, the heater needs to operate only
when water is flowing.
[0009] However, the instantaneous heating type water supply device
having such a heater frequently generates noise, and this may cause
burning or overheating and so degrade efficiency.
[0010] In particular, harmonic components such as noise or the
like, generated in the warm water supply device, may increase the
temperature of a transformer or the like that supplies power
thereto, thereby increasing the possibility of fire. Moreover, in
the case of flickering, load, applied to a power supply device,
changes suddenly, causing defective operations of other load
devices connected to the power supply device.
SUMMARY OF THE INVENTION
[0011] An aspect of the present invention provides a device for
supplying warm water and a method thereof, capable of preventing
burning or overheating by reducing the generation of noise,
particularly, harmonic components and flickers.
[0012] According to an aspect of the present invention, there is
provided a device for supplying warm water, the device including: a
first heater configured to have a first set capacity and heating
received water; a second heater configured to have a second set
capacity greater than the first set capacity and heating received
water; and a control part calculating heater driving cycles of the
first heater and the second heater according to a set water
temperature, and driving the first heater and the second heater
according to the heater driving cycles, wherein the control part
calculates the heater driving cycle of the first heater by using a
phase control method, and calculates the heater driving cycle of
the second heater by using a zero-crossing control method.
[0013] The control part may determine whether a temperature of
water received in the first heater and the second heater is lower
than the set water temperature, and calculate the heater driving
cycles when the temperature of the received water is lower than the
set water temperature.
[0014] The first set capacity may be greater than zero and lower
than 550 W, and the second set capacity may be equal to or greater
than 550 W and lower than 1250 W.
[0015] According to another aspect of the present invention, there
is provided a method of supplying warm water, the method including:
preparing a first heater having a first set capacity, and a second
heater having a second set capacity greater than the first set
capacity; calculating a heater driving cycle of the first heater
according to a set water temperature by using a phase control
method, while calculating a heater driving cycle of the second
heater according to the set water temperature by using a
zero-crossing control method; and driving the first heater and the
second heater according to the heater driving cycles to heat water
received in the first heater and the second heater, and discharging
the heated water.
[0016] The method may further include determining whether a
temperature of the water received in the first heater and the
second heater is lower than the set water temperature, wherein the
heater driving cycles are calculated when the temperature of the
water is lower than the set water temperature.
[0017] The first set capacity may be greater than zero and lower
than 550 W, and the second set capacity may be equal to or greater
than 550 W and lower than 1250 W.
[0018] According to another aspect of the present invention, there
is provided a method of supplying warm water, the method including:
a preparation operation in which a first heater having a first set
capacity, and a second heater having a second set capacity greater
than the first set capacity are prepared; an operation setting
operation in which a set water temperature and set water quantity
are input; an operation preparation operation in which water is
received in an amount equal to or greater than the set water
quantity, it is determined whether to perform heating according to
a temperature of the received water, and quantity of heat required
for the heating is calculated; and a control operation in which,
when the heating is required, at least one of the first heater and
the second heater is selected as a heater to be driven according to
the required quantity of heat, a heater driving cycle of the
selected heater is calculated, and the selected heater is driven
according to the heater driving cycle, wherein in the control
operation, a heater driving cycle of the first heater is calculated
by using a phase control method, and a heater driving cycle of the
second heater is calculated by using a zero-crossing control
method.
[0019] The control operation may include a first control operation
in which the first heater is selected as a heater to be driven when
the required quantity of heat is less than the first set capacity,
and the heater driving cycle of the first heater is calculated by
using the phase control method to thereby drive the first
heater.
[0020] The control operation may include a second control operation
in which the second heater is selected as a heater to be driven
when the required quantity of heat is equal to or greater than the
first set capacity and lower than the second set capacity, and the
heater driving cycle of the second heater is calculated by using
the zero-crossing control method to thereby drive the second
heater.
[0021] The control operation may include a third control operation
in which the first heater and the second heater are selected as
heaters to be driven when the required quantity of heat is equal to
or greater than the second set capacity, the heater driving cycle
of the first heater is calculated by using the phase control method
to thereby drive the first heater, and the heater driving cycle of
the second heater is calculated by using the zero-crossing control
method to thereby drive the second heater.
[0022] In the third control operation, the heater driving cycle of
the second heater may be calculated such that the second heater is
driven by the second set capacity, and the heater driving cycle of
the first heater may be calculated such that the first heater is
driven by a capacity obtained by subtracting the second set
capacity from the required quantity of heat.
[0023] The operation preparation operation may include: receiving
water in an amount equal to or greater than the set water quantity;
measuring a water temperature of the received water; calculating
the required quantity of heat for heating when the measured water
temperature is lower than the set water temperature; and
discharging water when the measured water temperature is equal to
or higher than a preset temperature, and going into a standby
state, wherein the preset temperature is equal to or higher than
the set water temperature, and the measuring of the water
temperature is performed again when the water temperature is equal
to or higher than the set water temperature and lower than the
preset temperature.
[0024] The first set capacity may be greater than zero and lower
than 550 W, and the second set capacity may be equal to or greater
than 550 W and lower than 1250 W.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The above and other aspects, features and other advantages
of the present invention will be more clearly understood from the
following detailed description taken in conjunction with the
accompanying drawings, in which:
[0026] FIG. 1 is a block diagram illustrating a warm water supply
control system according to an exemplary embodiment of the present
invention;
[0027] FIG. 2 is a graph showing a phase control method according
to an exemplary embodiment of the present invention;
[0028] FIG. 3 is a graph illustrating a zero-crossing control
method according to an exemplary embodiment of the present
invention;
[0029] FIG. 4 is a table showing the results of a harmonic test and
a flicker test according to heater capacity, according to an
exemplary embodiment of the present invention;
[0030] FIG. 5 is a flowchart illustrating a method of supplying
warm water according to an exemplary embodiment of the present
invention;
[0031] FIG. 6 is a flowchart illustrating a method of supplying
warm water according to another exemplary embodiment of the present
invention; and
[0032] FIG. 7 is a flowchart illustrating a preparation operation
of a method of supplying warm water according to another exemplary
embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0033] Exemplary embodiments of the present invention will now be
described in detail with reference to the accompanying drawings.
The invention may, however, be embodied in many different forms and
should not be construed as being limited to the embodiments set
forth herein. Rather, these embodiments are provided so that this
disclosure will be thorough and complete, and will fully convey the
scope of the invention to those skilled in the art. In the
drawings, the shapes and dimensions of elements may be exaggerated
for clarity. The same or equivalent elements are referred to by the
same reference numerals throughout the specification.
[0034] FIG. 1 is a block diagram illustrating a warm water supply
control system according to an exemplary embodiment of the present
invention. Referring to FIG. 1, the warm water supply control
system includes a warm water supply device 100, a main control
device 200, and a water supply valve 300.
[0035] The warm water supply device 100 includes a power control
signal generation part 10, a first heater 20a, a second heater 20b,
a heater driving protection part 30, a water quantity detection
part 40, a temperature detection part 50, a communications part 60,
and a control part 70. The parts of the warm water supply device
100 will now be described in detail.
[0036] The first heater 20a and the second heater 20b heat water,
being introduced therein, and discharge the heated water. The first
heater 20a is configured to have a first set capacity, which is
greater than zero and lower than 550 W. The second heater 20b has a
second set capacity which is greater than the first set capacity.
Here, the second set capacity is equal to or greater than 550 W and
lower than 1250 W.
[0037] The water quantity detection part 40 detects the quantity of
water introduced to the first heater 20a and the second heater 20b,
and sends information regarding the water quantity to the heater
driving protection part 30.
[0038] The heater driving protection part 30 determines whether the
quantity of water, introduced to the first heater 20a and the
second heater 20b, is equal to or greater than a preset value. When
the quantity of water is equal to or greater than the preset value,
the heater driving protection part 30 generates a heater driving
enabling signal and sends it to the control part 70.
[0039] The power control signal generation part 10 receives
alternating current (AC) power, obtains the period and zero point
of the AC power, and transmits them to the control part 70. A
heater driving signal from the control part 70 is generated
according to a heater driving cycle calculated on the basis of the
period and zero point of the AC power, provided from the power
control signal generation part 10.
[0040] The temperature detection part 50 detects a water
temperature of water discharged from the first heater 20a and the
second heater 20b. The temperature detection part 50 detects a
water temperature when the quantity of water introduced to the
first heater 20a and the second heater 20b is equal to or greater
than a preset value.
[0041] The control part 70 calculates the heater driving cycles of
the first and second heaters 20a and 20b on the basis of a set
water temperature (i.e., a target water temperature of the water
being heated), and drives the first and second heaters 20a and 20b
according to the heater driving cycles. The control part 70
determines whether the water temperature of water introduced into
the first and second heaters 20a and 20b is lower than the set
water temperature. When the water temperature is lower than the set
water temperature, the control part 70 calculates heater driving
cycles upon receiving information regarding water quantity from the
water quantity detection part 40, information regarding a set water
temperature from the main control device 200, and information
regarding a water temperature from the temperature detection part
50. In this case, the control part 70 uses a phase control method
to calculate a heater driving cycle for the first heater 20a, and
uses a zero-crossing control method to calculate a heater driving
cycle for the second heater 20b.
[0042] Further, the control part 70 determines whether a heater
driving enabling signal is received from the heater driving
protection part 30. When the heater driving enabling signal is
received, the control part 70 allows for the heating of water being
introduced. The control part 70 receives the heater driving
enabling signal so as not to generate a heater driving signal even
when no water is introduced into the first heater 20a and the
second heater 20b.
[0043] The communications part 60 sends a value of the set water
temperature, received from the main control device 200, to the
control part 70, and sends the quantity of discharged water from
the control part 70 and a water temperature of the discharged water
to the main control device 200. Moreover, the communications part
60 receives a Direct Current (DC) power voltage from the main
control device 200, and sends it to the power control signal
generation part 10, the first heater 20a, the second heater 20b,
the heater driving protection part 30, the water quantity detection
part 40, the temperature detection part 50, the communications part
60, and the control part 70.
[0044] When a user requests a specific operation (e.g., washing,
bidet or the like), the main control device 200 detects this
request and turns on the water supply valve 300 so that water is
introduced into the first heater 20a and the second heater 20b. In
addition, the main control device 200 sends a value of the set
water temperature to the control part 70 of the warm water supply
device 100 so that the warm water supply device 100 can perform a
heating operation according to the set water temperature.
[0045] The water supply valve 300 controls water supply by being
turned ON/OFF in response to the request from the main control
device 200.
[0046] The warm water supply device according to this exemplary
embodiment may be used for, representatively, a bidet, and may be
applied to other devices adopting such a principle.
[0047] FIG. 2 is a graph illustrating a phase control method.
Referring to FIG. 2, the upper graph of FIG. 2 shows an input power
voltage V over time t, and the lower graph thereof shows a phase
control voltage V over time t. When a heater is driven at the input
power voltage corresponding to the upper graph of FIG. 2 by using a
phase control method, the phase control voltage, as shown in the
lower graph of FIG. 2 is output.
[0048] The phase control method is a method of cutting off power at
a zero voltage by applying a power voltage to a heater in a
specific phase at each half cycle. Here, a phase angle at which the
power voltage is applied is referred to as a conduction angle.
[0049] This phase control method has a defect of noise generation
caused by harmonics. A heater capacity of 550 W or higher renders
the device to fail a harmonic test, one of the subjects of CE
test.
[0050] FIG. 3 is a graph illustrating a zero-crossing control
method according to an exemplary embodiment of the present
invention. Referring to FIG. 3, the upper graph illustrates an
input power voltage V over time t, and the lower graph illustrates
a zero-crossing control voltage V over time t. When a heater is
driven at the input power voltage, as shown in the upper graph, by
the use of a zero-crossing control method, the zero-crossing
control voltage as shown in the lower graph is output.
[0051] The zero-crossing control method is a method of applying
only a positive power voltage when an AC power voltage is applied
to a heater.
[0052] This zero-crossing control method does not generate noise
caused by harmonics. Thus, when a heater capacity is equal to or
greater than 550 W and lower than 1250 W, requirements to pass a
harmonic test, a CE test, cannot be satisfied (thus, the harmonic
test or the CE test is failed).
[0053] FIG. 4 is a table showing the result of harmonic tests and
flicker tests according to the heater capacity according to an
exemplary embodiment of the present invention. Here, P represents
pass, and F represents fail.
[0054] Referring to FIG. 4, a heater capacity of 450 W or 550 W
satisfies requirements to pass both the harmonic test and the
flicker test regardless of whether the phase control method or the
zero-crossing control method is used.
[0055] However, in the case that the heater capacity is 550 W, 650
W or 750 W, requirements for both the harmonic test and the flicker
test can be met (Pass) only when the zero-crossing control method
is used. When the phase control method is used, the warm water
supply device may pass the flicker test but fail the harmonic
test.
[0056] Moreover, in the case that the heater capacity is 1250 W and
the phase control method is used, the warm water supply device may
pass the flicker test but fail the harmonic test. When the
zero-crossing control method is used, the warm water supply device
may pass the harmonic test but fail the flicker test.
[0057] A reference value for the harmonic test, a CE test, is
determined by setting a predetermined margin to a boundary value at
which harmonic noise, generated by the warm water supply device,
does not affect a power supply device connected to the warm water
supply device.
[0058] Accordingly, by designing the warm water supply device to
meet the reference value of the harmonic test, the power supply
device, supplying power to the warm water supply device, is
prevented from generating heat due to harmonics.
[0059] Moreover, an increase in harmonic components may result in
the excessive consumption of power. Namely, the increase in
harmonic components may increase power consumption, which is in
proportion to the square of a frequency value.
[0060] The reference value of the flicker test of the CE test is
determined by setting a predetermined margin to a boundary value at
which the operation of other load devices connected to the power
supply device is not affected by flicker components generated by
the warm water supply device.
[0061] In particular, since devices such as lamps are sensitive to
a change in supply current, the generation of flicker components in
the warm water supply device may cause inconvenient to a user.
Moreover, other load devices therein are susceptible to damage
since current supply may suddenly increase or decrease.
[0062] Therefore, the stable operation of other load devices
connected to the power supply device may be ensured by designing
the warm water supply device to meet the reference value for the
flicker test of the CE test.
[0063] As shown in FIG. 4, when a single heater is provided to the
warm water supply device and is driven by using the phase control
method, a heater capacity of 550 W or higher may meet the
requirements for the harmonic test of the CE test.
[0064] To overcome such a defect, according to this exemplary
embodiment, two heaters are provided to control the supply of warm
water. That is, when a heater capacity needs to be 1250 W, two
heaters having respective heater capacities of 500 W and 750 W are
provided. In this case, the heater of 500 W is driven by using the
phase control method, while the heater of 750 W is driven by using
the zero-crossing control method.
[0065] As described above, the warm water supply device is provided
with the two heaters with the respective heater capacities of 500 W
and 750 W. As a result, the warm water supply device can pass both
the harmonic test and the flicker test, overcoming the limitation
of failing the harmonic test while passing the flicker test in the
case of using the phase control method, and of failing the flicker
test while passing the harmonic test in the case of using the
zero-crossing control method at the time the heater capacity is
1250 W.
[0066] As for heater construction, respective heaters of 500 Wand
750 W for a heater capacity of 1250 W have been described. However,
the heater capacity may be varied provided that one heater has a
first set capacity while the other heater has a second set
capacity. That is, heaters of 450 W and 800 W may be configured in
order to realize the heater capacity of 1250 W.
[0067] Further, even when three or more heaters are provided to
achieve the capacity of 1250 W and are driven by using the phase
control method, the warm water supply device according to this
exemplary embodiment may pass the harmonic test and the flicker
test. However, the construction including three heaters is more
complicated than when two heaters are provided. Thus, the warm
water supply device may be provided with two heaters.
[0068] FIG. 5 is a flowchart illustrating a method of supplying
warm water according to an exemplary embodiment of the present
invention. FIG. 5 will now be explained together with FIG. 1.
[0069] In operation S10, the first heater 20a having a first set
capacity and the second heater 20b having a second set capacity
greater than the first set capacity are prepared.
[0070] Thereafter, when a set water temperature sent from the main
control device 200 is input to the control part 70 in operation
S20, the water quantity detection part 40 detects the quantity of
water flowing into the first heater 20a and the second heater 20b
in operation S30, and determines whether the detected water
quantity is greater than a preset value in operation S40.
[0071] Subsequently, when the detected water quantity is equal to
or greater than the preset value, the temperature detection part 50
detects the temperature of water discharged from the first heater
20a and the second heater 20b in operation S50. However, when the
detected water quantity does not reach the water quantity,
operation S40 is repeated.
[0072] Thereafter, the control part 70 determines whether the water
temperature of water introduced into the first heater 20a and the
second heater 20b is lower than the set water temperature in
operation S60. However, when the water temperature is not lower
than the set water temperature, the process is fed back to
operation S50.
[0073] Thereafter, when the water temperature is lower than the set
water temperature, the control part 70 calculates the driving
cycles of the first heater 20a and the second heater 20b in
operation S70 upon receiving information regarding the water
quantity reported from the water quantity detection part 40,
information regarding the set water temperature provided from the
main control device 20-, and information regarding the temperature
of water received from the temperature detection part 50. In this
operation, the control part 70 uses the phase control method in
calculating the heater driving cycle of the first heater 20a, and
uses the zero-crossing control method in calculating the heater
driving cycle of the second heater 20b.
[0074] Subsequently, the control part 70 determines whether a
heater driving enabling signal, sent from the heater driving
protection part 30, is received in operation S80. In order to drive
the first heater 20a and the second heater 20b, the control part 70
needs to receive a heater driving enabling signal from the heater
driving protection part 30. The control part 70 receives the heater
driving enabling signal from the heater driving protection part 30
in order to prevent the control part 70 from generating a heater
driving signal even when water does not flow into the first heater
20a and the second heater 20b.
[0075] Thereafter, when the heater driving enabling signal is
received, the control part 70 generates a heater driving signal
according to a heater driving cycle calculated on the basis of the
period and zero point of AC power supplied from the power control
signal generation part 10 in operation S90. However, when the
control part 70 does not receive the heater driving enabling signal
in operation S80, the first heater 20a and the second heater 20b
are not able to heat water being introduced, and thus the process
is fed back to operation S400.
[0076] Subsequently, the first heater 20a and the second heater 20b
heat water introduced thereinto, and discharge the heated water in
operation S100.
[0077] FIG. 6 is a flowchart illustrating a method of supplying
warm water according to another exemplary embodiment of the present
invention.
[0078] First, the first heater 20a having a first set capacity and
the second heater 20b having a second set capacity are
prepared.
[0079] Thereafter, in an operation setting operation S200, a set
water temperature and set water quantity may be input. Here, the
set water temperature refers to a target water temperature of water
being discharged, and the set water quantity refers to target
quantity or target pressure of water being discharged. In the
operation setting operation S200, the set water temperature and the
set water quantity may be input directly by a user or by reading
pre-stored or stored use patterns.
[0080] In an operation preparation operation S300, water to be
heated is received in an amount equal to or greater than the set
water quantity, and it may be determined whether heating is to be
performed or how much heat is required according to a water
temperature of the received water. Whether to perform heating may
be determined by comparing the set water temperature with the
temperature of the received water. When it is determined that
heating is required, the quantity of heat required for the heating
operation may be calculated in due consideration of the water
quantity, the set water temperature and the like.
[0081] When the required quantity of heat is less than the first
set capacity in operation S400, a first control operation S500 is
performed. In the first control operation S500, a heater driving
cycle of the first heater is calculated by using the phase control
method, and the first heater may be driven accordingly.
[0082] When the required quantity of heat is equal to or greater
than the first set capacity and less than second set capacity in
operation S600, a second control operation S700 is performed. In
the second control operation S700, the heater driving cycle of the
second heater is calculated by using the zero-crossing control
method, and the second heater the zero-crossing method is driven
accordingly.
[0083] When the required quantity of heat is equal to or greater
than the second set capacity in operation S600, a third control
operation S800 is performed. In the third control operation S800,
the heater driving cycle of the first heater is calculated by using
the phase control method and the first heater is driven
accordingly, while the heater driving cycle of the second heater is
calculated by using the zero-crossing method and the second heater
is driven accordingly.
[0084] Although not shown, it can be checked whether an error is
generated and whether an operation time expires during the first,
second or third control operation S500, S700 or S800.
[0085] When an error occurs or an operation time expires in the
first, second or third control operations S500, S700 or S800, the
first, second or third control operation S500, S700 or S800 may be
stopped and in a standby state.
[0086] When no error occurs and the operation time does not expire
in the first, second or third operation S500, S700 or S800, an
operation goes into the standby state. In this case, only the
operations of determining whether to perform heating and
calculating the quantity of heat for heating may be performed
according to a temperature of received water, without any
additional water supply.
[0087] In the third control operation S800, a different control
method may be used according to priority in using the first heater
20a and the second heater 20b.
[0088] For example, in the third control operation S800, when the
second heater 20b has higher priority, the heater driving cycle is
calculated such that the second heater 20b is driven by the second
set capacity, and the heater driving cycle for the first heater 20a
may be calculated such that the first heater 20a is driven by a
capacity obtained by subtracting the second set capacity from the
required quantity of heat.
[0089] In the third control operation S800, when the first heater
20a has higher priority, the heater driving cycle is calculated
such that the first heater 20a is driven by the first set capacity,
and the heater driving cycle for the second heater 20b may be
calculated such that the second heater 20b is driven by a capacity
obtained by subtracting the first set capacity from the required
quantity of heat.
[0090] A heater that undergoes less change in an ability to control
a water temperature according to the required quantity of heat may
have lower priority. For a heater that undergoes a severe change in
an ability to control a water temperature, it is not easy to
control a water temperature when the quantity of water to be heated
changes. Therefore, the quantity of water may be determined such
that the quantity of heat, required for heating, becomes identical
to the set capacity of the heater. This is because, when the
required quantity of heat is identical to the set capacity of the
heater, a large amount of water needs to be heated, and thus the
range of a temperature change is reduced, thereby contributing to
enhancing the ability to control the water temperature.
[0091] Referring to FIG. 6, the method of supplying warm water,
according to this exemplary embodiment, enables the efficient use
of a heater and achieves power saving by separately controlling the
first and second heaters 20a and 20b. Furthermore, the separate
control of the first and second heaters leads to precise
temperature control, and prevents unnecessary energy consumption,
thereby minimizing power consumption.
[0092] FIG. 7 is a flowchart illustrating an operation preparation
operation of a method of supplying warm water according to another
exemplary embodiment of the present invention.
[0093] First, water to be heated is received in operation S310, and
it is measured whether the quantity of received water corresponds
to a set heater capacity in operation S320, thereby rendering the
water quantity to be equal to or greater than the set heater
capacity.
[0094] Thereafter, a temperature of the received water is measured
in operation S330, and the measured water temperature is compared
with a set water temperature in operation S340.
[0095] A water temperature lower than the set water temperature
means that heating is required. Therefore, the quantity of heat
required for heating the received water is calculated on the basis
of the set water temperature and the quantity water in operation
S350.
[0096] However, when the set water temperature is low, water may be
discharged without being heated. However, the excessively low set
water temperature makes the temperature of water being discharged
so low that a user may experience inconvenience. Since there is a
high possibility that setting the set water temperature to a
excessively low level while using a warm water supply device may be
a mistake of a user, water may be caused to be discharged without
heating only when the set water temperature is equal to or higher
than a predetermined level.
[0097] As one example of implementing the above-stated setting,
when the water temperature is equal to or higher than the set water
temperature in operation S340 and is less than a preset temperature
in operation S360, received water is discharged and the operation
goes into a standby state.
[0098] The preset temperature needs to be equal to or higher than
the set water temperature. For example, the preset temperature may
be set to 41.degree. C., which is marginally higher than body
temperature, causing no inconvenience to a user.
[0099] As set forth above, according to the device for supplying
warm water and the method thereof according to exemplary
embodiments of the invention, two heaters are provided and adopt
the phase control method and the zero-crossing control method,
respectively. Accordingly, noise generation is suppressed as
compared to the case of employing a single heater, thereby
preventing the burning or overheating of the warm water supply
device and increasing the efficiency thereof.
[0100] In addition, according to the device for supplying warm
water and the method thereof, the set capacities of the heaters are
adjusted such that harmonic components and flickers are reduced and
thus do not affect the operations of a power supply device and
other load devices connected to the power supply device.
[0101] While the present invention has been shown and described in
connection with the exemplary embodiments, it will be apparent to
those skilled in the art that modifications and variations can be
made without departing from the spirit and scope of the invention
as defined by the appended claims.
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