U.S. patent application number 11/889684 was filed with the patent office on 2008-02-21 for microwave oven with a toaster and method for controlling a heater of the toaster.
This patent application is currently assigned to Daewoo Electronics Corporation. Invention is credited to Yun Ho Cho, Gil Ju Jung, Jae Hyun Lee.
Application Number | 20080041846 11/889684 |
Document ID | / |
Family ID | 36652252 |
Filed Date | 2008-02-21 |
United States Patent
Application |
20080041846 |
Kind Code |
A1 |
Lee; Jae Hyun ; et
al. |
February 21, 2008 |
Microwave oven with a toaster and method for controlling a heater
of the toaster
Abstract
A microwave oven with a toaster includes a toaster casing, a
heating chamber inserted in the toaster casing, a bread receiver
slidably inserted in the toaster casing, and a toaster door
attached to a front side of the bread receiver. The bread receiver
is selectively placed in the heating chamber. The microwave oven
further includes a crumb tray slidably inserted in the toaster
casing for collecting crumbs of bread and a holding unit for
holding bread put in the bread receiver. The crumb tray is placed
under the bread receiver. Further, there is provided a process for
controlling a heater of the toaster, which is capable of properly
baking bread even when the toaster is continually operated.
Inventors: |
Lee; Jae Hyun; (Seoul,
KR) ; Jung; Gil Ju; (Seoul, KR) ; Cho; Yun
Ho; (Seoul, KR) |
Correspondence
Address: |
BACON & THOMAS, PLLC
625 SLATERS LANE
FOURTH FLOOR
ALEXANDRIA
VA
22314
US
|
Assignee: |
Daewoo Electronics
Corporation
|
Family ID: |
36652252 |
Appl. No.: |
11/889684 |
Filed: |
August 15, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11372112 |
Mar 10, 2006 |
|
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|
11889684 |
Aug 15, 2007 |
|
|
|
10867759 |
Jun 16, 2004 |
7041948 |
|
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11372112 |
Mar 10, 2006 |
|
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Current U.S.
Class: |
219/680 |
Current CPC
Class: |
H05B 6/68 20130101; A47J
37/08 20130101; A47J 37/0814 20130101; H05B 2206/042 20130101; H05B
6/80 20130101 |
Class at
Publication: |
219/680 |
International
Class: |
H05B 6/06 20060101
H05B006/06 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 30, 2003 |
KR |
10-2003-0043448 |
Jun 30, 2003 |
KR |
20-2003-0020719 |
Jun 30, 2003 |
KR |
20-2003-0020723 |
Jun 30, 2003 |
KR |
20-2003-0020724 |
May 14, 2004 |
KR |
10-2004-0034086 |
Claims
1. A method for controlling a heater of a toaster incorporated in a
microwave oven, the method comprising the steps of: (a) setting a
heater ON time and a heater OFF time; (b) actuating the heater for
the heater ON time after the heater OFF time has elapsed; (c)
determining whether or not the toaster is repeatedly operated, and
if yes, resetting the heater OFF time by adding a predetermined
time thereto and the heater ON time by subtracting a predetermined
time therefrom; and (d) repeating the steps (b) and (c).
2. The method of claim 1, wherein in the step (c), the toaster is
determined to be repeatedly operated when the toaster is again
operated within a predetermined time after the heater ON time has
elapsed in the step (b).
3. The method of claim 1, wherein in the step (c), the toaster is
determined to be repeatedly operated when a continual operation
button is pushed.
4. The method of claim 1, wherein in the step (c), if the toaster
is repeatedly operated, a continual toaster operation number is
increased, and wherein when the continual toaster operation number
is equal to or greater than a predetermined critical operation
number, the heater OFF time and the heater ON time are not reset in
the step (c), and the steps (b) and (c) are repeated under a
condition that the heater OFF time and the heater ON time are kept
unchanged.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This Application is a divisional of and claims the benefit
of the earlier filing date of co-pending U.S. patent application
Ser. No. 11/372,112, filed Mar. 10, 2006, which is a divisional
application of granted Ser. No. 10/867,759, filed Jun. 16, 2004
(now U.S. Pat. No. 7,041,948), of which the entire disclosure is
hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a microwave oven with a
toaster; and, more particularly, to a microwave oven with a toaster
having an improved structure and a method for controlling a heater
of the toaster.
BACKGROUND OF THE INVENTION
[0003] In general, a microwave oven with a toaster is an appliance
capable of toasting food (e.g., bread products) as well as
performing inherent functions of the microwave oven by using
microwaves.
[0004] Referring to FIG. 1, there is illustrated a conventional
microwave oven with a toaster as disclosed in U.S. Pat. No.
6,539,840. At a side potion of the microwave oven, there is
provided an electric device chamber 300 in which a magnetron 210
for generating microwaves, a high-voltage transformer 212 for
supplying high voltage to the magnetron 210, and a fan 314 for
generating an air flow to cool the electric devices are installed.
A toaster unit 200 for toasting break is disposed in front of the
electric device chamber 300. The toaster unit 200 is closed and
opened by a toaster door 230. As shown in FIG. 1, the toaster door
230 is positioned under a control panel 214 at which a plurality of
control buttons are provided. The toaster unit 200 includes a
casing 202 with a predetermined cavity and the toaster door 230 is
pivoted about a hinge shaft Ha to close and open the casing 202. A
heater for heating bread is provided in the casing 202. A pair of
cooperating levers 222 are at one ends thereof connected to middle
portion of both sides of the toaster door 130 and at the other ends
to both side of a tray 220 movably placed in the casing 202. The
cooperating levers 222 are pivotally connected to both of the
toaster door 230 and the tray 220. Accordingly, when the toaster
door 230 is opened and closed, the tray 220 and hence bread B put
therein are also moved forward and backward.
[0005] In such conventional arrangements, however, since the
toaster door 230 is pivoted about the hinge shaft Ha and connected
through the cooperating levers 222 to the tray 220, many components
are required and the assembling process thereof is complicated,
thereby decreasing the productivity of the microwave oven.
Moreover, in the operation of the toaster of the conventional
microwave oven, in case that the toaster is continually operated,
the heater is overheated so that bread is over-baked or burnt
black. In order to prevent the above problem, a user may set an
operation time of the heater at every operations based on his
experience; however, this is very cumbersome work.
SUMMARY OF THE INVENTION
[0006] It is, therefore, an object of the present invention to
provide a microwave oven with a toaster having a simpler and
improved structure.
[0007] It is another object of the present invention to provide a
microwave oven with a toaster capable of collecting crumbs of
bread.
[0008] It is still another object of the present invention to
provide a microwave oven with a toaster capable of preventing a
movement of bread put in a bread receiver to reduce crumbs of the
bread.
[0009] It is still further another object of the present invention
to provide a microwave oven with a toaster capable of simply and
positively securing a heater plate to a side wall of a heating
chamber.
[0010] It is still further another object of the present invention
to provide a microwave oven with a toaster capable of suppressing
heat transfer from the heater plate to the heating chamber.
[0011] In accordance with an aspect of the present invention, there
is provided a microwave oven with a toaster comprising: a toaster
casing; a heating chamber inserted in the toaster casing; a bread
receiver slidably inserted in the toaster casing, the bread
receiver being selectively placed in the heating chamber; and a
toaster door attached to a front side of the bread receiver.
[0012] In accordance with another aspect of the present invention,
there is provided a method for controlling a heater of a toaster
incorporated in a microwave oven, the method comprising the steps
of: (a) actuating the heater for a heater ON time; and (b)
determining whether or not the toaster is continually operated, and
if yes, the heater ON time is gradually decreased as the continual
toaster operation number is increased.
[0013] In accordance with still another aspect of the present
invention, there is provided a method for controlling a heater of a
toaster incorporated in a microwave oven, the method comprising the
steps of: (a) setting a heater ON time and a heater OFF time; (b)
actuating the heater for the heater ON time after the heater OFF
time has elapsed; (c) determining whether or not the toaster is
continually operated, and if yes, resetting the heater OFF time by
adding a predetermined time thereto and the heater ON time by
subtracting a predetermined time therefrom; and (d) repeating the
steps (b) and (c).
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The above and other objects and features of the present
invention will become apparent from the following description of
the preferred embodiments given in conjunction with the
accompanying drawings, in which:
[0015] FIG. 1 shows a schematic side sectional view of a
conventional microwave oven with a toaster;
[0016] FIG. 2 describes an exploded view of a microwave oven with a
toaster in accordance with the present invention;
[0017] FIG. 3 represents a perspective view of the microwave oven
shown in FIG. 2;
[0018] FIGS. 4A to 4C are partial cross sectional views showing a
stepped section and a holding unit for holding bread put in a bread
receiver of the toaster in FIG. 2;
[0019] FIGS. 5A and 5B are partial cross sectional views showing a
modified embodiment wherein a pair of guide rails are employed
instead of the stepped section;
[0020] FIG. 6 sets forth an enlarged view showing fastening members
and supporting members for positively securing a heater plate to
side walls of the heating chamber;
[0021] FIG. 7 depicts a cross sectional view of an assembly of the
heating chamber and the heater plate shown in FIG. 2;
[0022] FIG. 8A is a side view of the microwave oven of the present
invention;
[0023] FIG. 8B is an enlarged view of a circled part A in FIG. 8A
showing a connection between a toaster door and a crumb tray;
[0024] FIG. 9 is a flow chart of a process for controlling a heater
of the toaster in accordance with the present invention; and
[0025] FIG. 10 is a flow chart of another process for controlling a
heater of the toaster in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] Hereinafter, preferred embodiments of the present invention
will be described with reference to the accompanying drawings.
[0027] Referring to FIG. 2, there is shown an exploded view of a
microwave oven with a toaster in accordance with the present
invention. The toaster is provided at a side portion of the
microwave oven. The toaster includes a toaster casing 20 with an
approximate U-shape in section; a heating chamber 140 with an
approximate reverse U-shape in section, the heating chamber 140
being inserted in the toaster casing 20; a bread receiver 36
slidably inserted in the toaster casing 20, the bread receiver 36
being selectively placed in the heating chamber 140; a toaster door
30 attached to a front side of the bread receiver 36; and crumb
tray 60 for collecting crumbs of bread.
[0028] Disposed at a front side of the toaster casing 20 is a
casing cover 50 with a first opening 51 for the bread receiver 36
and a second opening 52 for the crumb tray 60. Further, a rear
cover 56 and an upper cover 136 are attached to a rear and an upper
side of the toaster casing 20, respectively. The bread receiver 36
and the crumb tray 60 are inserted through the first and the second
opening 51, 52 into the heating chamber 140, respectively.
[0029] Referring now to FIGS. 2 and 4A to 4C, a stepped section 21
is formed at a bottom of the toaster casing 20. The bread receiver
36 is placed on an upper portion 21a of the stepped section 21 and
slid thereon when a user pushes or pulls the toaster door 30. The
crumb tray 60 is placed and slid on a lower portion 21b of the
stepped section 21 and collects crumbs which may occur during the
baking operation and/or the movement or the bread. Alternatively,
as shown in FIGS. 5A and 5B, a pair of opposite guide rails 221 may
protrude inwardly from both side walls of the toaster casing 20 and
run in a sliding direction of the bread receiver 36. In this case,
the bread receiver 36 may be slidably placed on the guide rails 221
and the crumb tray 60 may be slidably placed on the bottom of the
toaster casing 20 under the bread receiver 36.
[0030] Further, as shown in FIGS. 8A and 8B, the crumb tray 60 has
a hook 60a and the toaster door 30 has at its lower portion a hook
receptacle 30a. By connecting the hook 60a with the hook receptacle
30a, the crumb tray 60 can be interlocked with the toaster door 30
and moved therewith. Specifically, the hook 60a extends from an
upper portion of the crumb tray 60 in a longitudinal direction
thereof and the hook receptacle 30a extends from a lower portion of
the toaster door 30 in an approximate L-shape. The hook 60a is
engaged with the hook receptacle 30a so that, when the toaster door
30 is moved, the crumb tray 60 is moved therewith. In case the user
wants to remove crumbs collected in the crumb tray 60, the user can
separate the crumb tray 60 from the toaster door 30 by releasing
the hook 60a from the hook receptacle 30a.
[0031] Installed in the bread receiver 36 is a holding unit 40 for
holding bread put in the bread receiver 36. The holding unit 40
includes a pair of holding members 42. The holding member 40 has a
plurality of (e.g., two) horizontal-extending rods 43 which are
vertically spaced apart from each other and a plurality of (e.g.,
six) vertical-extending rods 45 which are horizontally spaced from
each other to connect the horizontal-extending rods 43 together.
The lowermost rod 43 of the holding member 40 is inserted into a
corresponding recess 31 formed in the toaster door 30 and the
innermost vertical-extending rod 45 is extended below the bread
receiver 36 through a corresponding hole 37 formed in a bottom of
the bread receiver 36. Both ends of an elastic member 48, e.g., a
coiled spring, are respectively connected to, e.g., two uppermost
horizontal-extending rods 43 to pull them toward each other so that
a distance between the uppermost horizontal-extending rods 43
becomes narrower.
[0032] When the user pulls the toaster door 30 to draw out the
bread receiver 36 from the toaster casing 30, the bread receiver 36
is slid on the upper portion 21a of the stepped section 21. At that
time, the lower end portions of the innermost vertical-extending
rods 45 extending through the holes 37 are also moved along the
vertical walls of the stepped section 21 and come to contact with
protrusions 22 formed on the vertical walls, respectively. When the
user further pulls the toaster door 30, the lower end portions of
the innermost vertical-extending rods 45 are moved along the
respective protrusions 22 and pushed toward the longitudinal center
line of the bread receiver against the force of the spring 48 so
that the distance between the uppermost horizontal-extending rods
43 becomes wider. Under this condition, the user can easily take
out baked bread and/or put new bread into the bread receiver 36.
Preferably, the contact surface of each of the protrusions 22 is
gradually protruded from the vertical side wall of the stepped
section 21, to thereby facilitate the movement of the lower end
portions of the innermost vertical-extending rods 45.
[0033] In order to bake bread, the user pushes the toaster door 30
to put the bread receiver 36 into the heating chamber 140. As the
bread receiver 36 moves on and along the upper portion 21a of the
stepped section 21, the innermost vertical-extending rods 45 are
released from the protrusions 22 and the distance between the
uppermost horizontal-extending rods 43 becomes narrow again by the
force of the spring 48 to hold the bread in place. As a result,
during the movement of the bread receiver 36, the bread put therein
is prevented from being moved, thereby decreasing crumbs which may
occur during the movement of the bread receiver 36.
[0034] In addition, referring to FIGS. 2, 7 and 8, a heater plate
112 having a heater (not shown) is installed on an inner surface of
each side wall of the heating chamber 140. Fastening members 144
are provided at a front and a rear end of each side wall of the
heating chamber 140, respectively, the fastening members 144 being
inwardly protruded opposite to each other. The fastening members
144 are bent inwardly onto an inner surface of the heater plate 112
after the latter is placed on the inner surface of the side wall of
the heating chamber 140, to thereby hold the front and the rear end
portion of the heater plate 112. Further, supporting members 145
are provided at a lower end of each side wall of the heating
chamber 140 near the front and the rear end thereof, respectively.
The supporting members 145 are bent upwardly onto the inner surface
of the heater plate 112 after the latter is placed on the inner
surface of the side wall of the heating chamber 140, to thereby
support the lower end portion of the heater plate 112.
[0035] As shown in FIG. 6, it is preferable that the supporting
member 145 has a supporting portion 145a for supporting the lower
end of the heater plate 112 and a bendable portion 145b which is
bent onto the heater plate 112. Further, it is preferable that the
fastening member 144 and the bendable portion 145b have a
width-reduced part for easy bending thereof. The width of the
width-reduced part is determined to have a sufficient strength to
support the heater plate 112.
[0036] Moreover, referring to FIGS. 2 and 7, provided on the side
walls of the heating chamber 140 are a plurality of embossed
portions 110 protruded inwardly. In this embodiment, the embossed
portions 110 are vertically extended parallel to each other, but
the present invention is not limited thereto. For example, the
embossed portions 110 may be horizontally extended parallel to each
other or may be located sporadically. By the embossed portions 110,
there is provided space between the heating chamber 140 and the
heater plate 112 installed on the side wall thereof so that the
transfer of heat generated by the heater plate 112 to the heating
chamber 140 is reduced compared with a case that the heater plate
112 is closely installed on the side wall of the heating chamber
140 without any space therebetween. Moreover, by operating a fan
314 disposed in an electric device chamber 300 (see FIG. 1), an air
flow is generated between the heater plate 112 and the side wall of
the heating chamber 140 so that the transfer of heat from the
heater plate 112 to the heating chamber 140 can be further
reduced.
[0037] Hereinafter, a process for controlling the heater of the
toaster in accordance with the present invention will be described
with reference with FIG. 9.
[0038] When a user pushes a toaster operation button (not shown)
provided on a control panel (not shown) (S1), the toaster is
operated. A controller (not shown) sets the operation number n to 1
(n=1) (S2) and a heater OFF time T.sub.c and a heater ON time
T.sub.h to, e.g., 0 sec and 30 sec, respectively (S3). The
controller actuates the heater for the heater ON time T.sub.h after
the heater OFF time T.sub.c has elapsed (S4).
[0039] After the first toasting operation is completed, if the user
pushes a continual operation button (not shown), the controller
determines that this is a continual toaster operation (S5). Then,
the controller sets the operation number n to n+1 and determines
that this is the second operation (S6). At this time, the
controller determines whether or not the operation number n is
equal to or greater than a predetermined critical operation number
(S7). If yes, the step S4 is again performed. In the step S7, if it
is determined that the operation number is less than the
predetermined critical operation number, the controller sets the
heater OFF time T.sub.c to T.sub.c+.DELTA.c (for example, .DELTA.c
is 5 sec) and the heater ON time T.sub.h to T.sub.h-.DELTA.h (for
example, .DELTA.h is 3 sec) (S8). Then, the step S4 is performed
based on the heater OFF time T.sub.c and the heater ON time T.sub.h
reset in the step S8. For example, when the critical operation
number is 5, in the second operation, the steps S8 and S4 are
performed so that the heater is stopped for 5 sec and actuated for
27 sec after the heat OFF time (5 sec) has elapsed.
[0040] Thereafter, when the user pushes the continual operation
button again, the controller determines that this is the third
operation, and sets the heater OFF time T.sub.c to T.sub.c+.DELTA.c
and the heater ON time T.sub.h to T.sub.h-.DELTA.h at the step S8.
Then, the step S4 is performed based on the heater OFF time T.sub.c
and the heater ON time T.sub.h reset in the step S8. That is, the
heater is actuated for 24 sec after the heater OFF time (10 sec)
has elapsed.
[0041] In this way, as the continual operation number of the
toaster is increased, the heater OFF time T.sub.c is gradually
increased and the heater ON time T.sub.h is gradually
decreased.
[0042] However, after the operation number reaches the critical
operation number, the heater OFF time T.sub.c and the heater ON
time T.sub.h are kept unchanged. Specifically, after the fourth
toaster operation wherein the heater is energized for 21 sec after
the heater OFF time (15 sec) has elapsed, when the user pushes the
continual operation button for the fifth operation, the controller
determines that the operation number is equal to the predetermined
critical operation number and controls the toaster to perform the
step S4 without performing the step S8. Therefore, the heater OFF
time T.sub.c and the heater ON time T.sub.h are kept unchanged. (At
this time, the heater OFF time and the heater ON time are referred
to as a critical heater OFF time and a critical heater ON time,
respectively.)
[0043] After the fifth toaster operation, when the user pushes the
continual operation button for the sixth operation, the controller
determines that the operation number is greater than the
predetermined critical operation number and controls the toaster to
perform the step S4. Therefore, the heater OFF time T.sub.c and the
heater ON time T.sub.h are kept unchanged.
[0044] In this way, after the critical number of toaster operation,
the heater OFF time and the heater ON time are maintained at the
critical heater OFF time and the critical heater ON time,
respectively. Accordingly, even when many slices of bread are
continually toasted, it is possible to properly bake the slices of
bread.
[0045] The critical operation number can be properly selected
through an experiment based on, e.g., a heating capacity of the
heater, an initial heater OFF time T.sub.c, an initial heater ON
time T.sub.h, .DELTA.c and .DELTA.h. For example, in case that the
initial heater OFF time T.sub.c, the initial heater ON time
T.sub.h, .DELTA.c and .DELTA.h are respectively set to 0 sec, 30
sec, 3 sec and 2 sec, the critical operation number can be
experimentally set to 6. In this case, the critical heater OFF time
and the critical heater ON time will be 15 sec and 20 sec,
respectively.
[0046] In the above example, although the controller controls both
of the heater OFF time and the heater ON time, the controller may
control only the heater OFF time. A process wherein the controller
controls only the heater ON time will now be described with
reference to FIG. 10.
[0047] When the user pushes the toaster operation button provided
on a control panel (S11), the toaster is operated. The controller
sets the operation number n to 1 (n=1) (S12) and a heater ON time
T.sub.h to, e.g., 30 sec (S13). The controller actuates the heater
for the heater ON time T.sub.h (S14).
[0048] After the first toasting operation is completed, if the user
pushes the continual operation button, the controller determines
that this is a continual toaster operation (S15). Then, the
controller sets the operation number n to n+1 and recognizes that
this is the second operation (S16). At this time, the controller
determines whether or not the operation number n is equal to or
greater than a predetermined critical operation number (S17). If
yes, the step S14 is again performed. In the step S17, it is
determined that the operation number is less than the predetermined
critical operation number, the controller sets the heater ON time
T.sub.h to T.sub.h-.DELTA.h (for example, .DELTA.h is 4 sec) (S18).
Then, the step S14 is performed based on the heater ON time T.sub.h
reset in the step S18. For example, when the critical operation
number is 5, in the second operation, the steps S18 and S14 are
performed so that the heater is actuated for 26 sec.
[0049] Thereafter, when the user pushes the continual operation
button again, the controller determines that this is the third
operation, and resets the heater ON time T.sub.h to
T.sub.h-.DELTA.h at the step S18. Then, the step S14 is performed
based on the heater ON time T.sub.h reset in the step S18. That is,
the heater is actuated for 22 sec.
[0050] In this way, as the continual operation number of the
toaster is increased, the heater ON time T.sub.h is gradually
decreased.
[0051] However, after the operation number reaches the critical
operation number, the heater ON time T.sub.h is kept unchanged.
Specifically, when the user pushes the continual operation button
for the fifth operation after the fourth toaster operation wherein
the heater is energized for 14, the controller determines that the
operation number is equal to the predetermined critical operation
number and controls the toaster to perform the step S14. Therefore,
the heater ON time T.sub.h is kept unchanged. (At this time, the
heater ON time is referred to as a critical heater ON time.)
[0052] After the fifth toaster operation, when the user pushes the
continual operation button for the sixth operation, the controller
determines that the operation number is greater than the
predetermined critical operation number and controls the toaster to
perform the step S14. Therefore, the heater ON time T.sub.h is kept
unchanged.
[0053] In this way, after the critical number of toaster operation,
the heater ON time is maintained at the critical heater ON time.
Accordingly, even when many slices of bread are continually
toasted, it is possible to properly bake the breads.
[0054] The critical operation number can be properly selected
through an experiment based on, e.g., a heating capacity of the
heater, an initial heater ON time T.sub.h and .DELTA.h. For
example, in case that the initial heater ON time T.sub.h and
.DELTA.h are respectively set to 30 sec and 5 sec, the critical
operation number can be experimentally set to 4. In this case, the
critical heater ON time will be 15 sec.
[0055] In the above examples, the increment of the heater OFF time
.DELTA.c and the decrement of the heater ON time .DELTA.h are
constant; however, it is appreciated that they may be varied as the
continual toaster operation number is increased. For example, in
the first example, .DELTA.c may be 5, 6, 7 . . . sec and .DELTA.h
may be 3, 4, 5 . . . sec as the continual toaster operation number
is increased.
[0056] Further, in the above examples, there has been described
that the controller determines that the toaster is continually
operated when a user pushes the continual operation button, but the
present invention is not limited thereto. For example, the
controller may determines that the toaster is continually operated
when the toaster operation button is pushed within a predetermined
time (e.g., 10 sec) after the operation of the heater has been
stopped.
[0057] While the invention has been shown and described with
respect to the preferred embodiments, it will be understood by
those skilled in the art that various changes and modifications may
be made without departing from the spirit and the scope of the
invention as defined in the following claims.
* * * * *