Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02788503 2014-05-29
DRAIN HOLE FOR A LAUNDRY TREATING MACHINE
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a laundry treating machine, and more
particularly, to a laundry treating machine which can reduce noise generated
during
drainage.
Discussion of the Related Art
Generally, laundry treating machines are classified into washing machines
removing dirt or dust from clothes, bedclothes, etc (hereinafter, referred to
as
'laundry') by using water and detergent and using mechanical operations,
dryers
drying wet laundry by using a dry, hot wind generated by a heater and using
mechanical operations, and combination washer dryers performing both a washing
function and a drying function.
Also, the washing machines may be classified into a top loading type washing
machine having a laundry inlet/outlet hole formed in the top surface of a
cabinet and
through which laundry comes in and out and performing washing using a spinning
stream of water generated by the rotation of an inner tub and a drum washing
machine having a laundry inlet/outlet hole formed on the front surface of a
cabinet
and performing washing by the falling-out of laundry from a high point during
the
rotation of a drum.
A conventional top loading type washing machine includes a cabinet forming
an outer appearance of the washing machine and open at a top surface thereof,
a
top cover connected to the open top surface of the cabinet, a door rotatable
installed
on the laundry inlet/outlet hole, a base installed at the bottom of the
cabinet, an outer
tub installed inside the cabinet and storing water, an inner tub disposed
inside the
outer tub and performing washing of laundry, a motor unit disposed below the
inner
tub to rotate the inner tub, a water supply unit for supplying water into the
outer tub,
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and a drain unit for draining the water in the outer tub. Further, the washing
machine
includes a detergent supply device disposed to communicate with the water
supply
unit, for supplying detergent along with water.
The drain unit includes a drain hose connected to a drain port formed on the
bottom of the outer tub and a drain pump disposed on the drain hose to pump
washing water.
However, the conventional top loading type washing machine creates a
vortex because of a temporary decrease in the water pressure of the drain port
caused by a difference between an amount of drainage and an amount of pumping
in an early stage of drainage. If a vortex is generated, air enters through an
upper
side of the drain port to form an air layer through which no water flows, and
abnormal noise is generated in an early stage of drainage due to the air
layer. Noise
generated during drainage makes users feel uncomfortable. Moreover, the air
layer
causes lowering of pumping performance.
Summary of the Invention
In accordance with one aspect of the invention there is provided a laundry
treating machine including an outer tub for storing washing water and having a
heater mounting groove which is formed concave on a bottom surface. The heater
mounting groove is provided with a drain hole formed on the bottom surface for
discharging washing water, and a heater disposed in the heater mounting groove
for
heating washing water. A heater cover is disposed to cover the heater mounting
groove. The heater cover includes at least one heater cover hole through which
washing water is able to flow. An upper side of the drain hole is covered by
the
heater cover and the heater cover hole is disposed at a position beside the
upper
side of the drain hole not overlapping the drain hole.
The heater cover hole may be disposed such that a circumference of the
heater cover hole is separated from a circumference of the drain hole in a
vertical
and a horizontal direction by a predetermined distance.
The heater cover may cover the heater mounting groove, and may be
disposed flat with the bottom surface of the outer tub.
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,
The at least one heater cover hole may include a plurality of heater cover
holes shaped differently and disposed at the different positions on the heater
cover.
In one aspect, the laundry treating machine includes a silencer covering the
vertical top of the drain hole, whereby the top of the drain hole is always
filled with
washing water and the generation of a vortex is prevented. Thus, abnormal
noise
during drainage may be prevented, thereby contributing to a quiet operation of
the
washing machine and improving consumer trust.
Moreover, as the silencer may include a drain hole cap, the laundry washing
machine may allow washing water to be introduced in a lateral direction while
covering the vertical top of the drain hole. Thus, the drainage of the washing
water
can be properly carried out, and abnormal noise during drainage may be
prevented.
Furthermore, in another aspect, the laundry treating machine may have the
advantage of simple structure and easy installation since the silencer
includes a
plate shaped drain hole cover.
In another aspect, the laundry treating machine may include a heater cover
which is disposed in the heater mounting groove so as to cover the top of the
heater
and cover the vertical top of the drain hole, such that washing water is
drained after
being filled between the heater cover and the drain hole, thereby preventing
the
generation of a vortex and abnormal noise.
In addition, in another aspect the laundry treating machine may include a
heater cover hole which is formed in the heater cover for emitting heat
generated
from the heater and assisting in drainage and is disposed at a position not
overlapping with the drain hole having the advantage that both heat emission
and
drainage are properly carried out.
Additionally, the laundry treating machine may include a heater cover which is
disposed for covering the heater mounting groove, having the advantage that a
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washing water stream can be properly formed by eliminating a stepped part of
the
bottom surface of the outer tub.
Brief Description of the Drawings
The above features of the present invention will become apparent from the
following description of preferred embodiments, given in conjunction with the
accompanying drawings, in which:
FIG. 1 is a perspective view of a top loading type washing machine according
to a first exemplary embodiment of the present invention;
FIG. 2 is a longitudinal cross-sectional view of the washing machine shown in
FIG. 1;
FIG. 3 is a perspective view showing an installation structure of a drain hole
cap shown in FIG. 1;
FIG. 4 is an enlarged perspective view of the drain hole cap shown in FIG. 3;
FIG. 5 is a cross-sectional view showing part A of FIG. 2;
FIG. 6 is a cross-sectional view comparing the presence and absence of a
drain port cap;
FIG. 7 is a perspective view of a drain hole cap according to a second
exemplary embodiment of the present invention;
FIG. 8 is a cross-sectional view of a washing machine according to a third
exemplary embodiment of the present invention;
FIG. 9 is a perspective view showing part B of FIG. 8;
FIG. 10 is a perspective view of a silencer shown in FIG. 9;
FIG. 11 is a cross-sectional view taken along line V-V of FIG. 9;
FIG. 12 is a plan view of a silencer according to a fourth exemplary
embodiment of the present invention;
FIG. 13 is a perspective view of the silencer shown in FIG. 12;
FIG. 14 is a cross-sectional view taken along line I-1 of FIG. 12.
FIG. 15 is a longitudinal cross-sectional view of a washing machine according
to a fifth exemplary embodiment of the present invention;
FIG. 16 is a view showing part C of FIG. 15; and
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FIG. 17 is a plan view showing a heater cover shown in FIG. 16.
Detailed Description of the Preferred Embodiment
Hereinafter, a top loading type washing machine (hereinafter, referred to as
'washing machine') according to an exemplary embodiment of the present
invention
will be described in detail with reference to the accompanying drawings.
FIG. 1 is a perspective view of a top loading type washing machine according
to a first exemplary embodiment of the present invention, and FIG. 2 is a
longitudinal
cross-sectional view of the washing machine shown in FIG. 1.
Referring to FIGS. 1 and 2, the washing machine according to the first
exemplary embodiment of the present invention comprises a case 1 forming an
outer
appearance of the washing machine and a leg assembly 10 connected to the
bottom
of the case 1.
The case 1 comprises a cabinet 2 configured to be open at the top and
bottom surfaces and constituting the sides of the washing machine, a top cover
installed so as to cover the open top surface of the cabinet 2, and a base 5
installed
on the open bottom surface of the cabinet 2.
Within the cabinet 2, there are provided an outer tub 4 for holding water, an
inner tub 6 disposed inside the outer tub 4 and receiving laundry therein, a
driving
mechanism such as a motor 8 for driving the inner tub 6, a water supply
assembly
for supplying water into the outer tub 4, and a drainage assembly 20 for
draining the
water in the outer tub 4 after completion of washing or dehydration.
Moreover, the case 1 further comprises a detergent supply unit 30 installed at
the top cover 3 and temporarily storing detergent therein. The detergent
supply unit
is connected to the water supply assembly to supply detergent along with
supplied water into the inner tub 6.
The top cover 3 includes a laundry inlet/outlet hole 3a for loading or
unloading
laundry. A door 50 for opening and closing the laundry inlet/outlet hole 3a is
30
installed at the top cover 3. At least part of the door 40 may be made of
glass to
make visible the inside thereof. That is, the door 40 comprises a frame part
40a and
a glass part 40b fit to the frame part 40a.
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Moreover, a display panel 7 is mounted at one side of the top cover 3 to input
an operation of the washing machine or display operating conditions of the
washing
machine.
The outer tub 4 is disposed at an inner upper part of the cabinet 2 so as to
be
suspended by a plurality of suspensions 15. One ends of the suspensions 15 may
be coupled to inner upper parts of the cabinet 2, and the other ends thereof
may be
coupled to lower parts of the outer tub 4.
A pulsator 9 is installed on the bottom surface of the inner tub 6 to form a
spinning stream of water held in the outer tub 4. The pulsator 9 may be
integrally
formed with the inner tub 6 to thus enable the pulsator 9 to rotate together
with the
inner tub 6 during rotation of the motor 8, or the pulsator 9 may be formed
separately
from the inner tub 6 to thus allow the pulsator 9 to rotate separately during
rotation of
the motor 8.
A balancer 15 is installed at an upper side of the inner tub 6 to prevent the
inner tub 6 from losing balance due to laundry leaning to one side. The
balancer 15
may be a liquid balancer having a liquid such as salt water filled therein.
An outer tub cover 14 is installed at an upper side of the outer tub 4 to
prevent laundry from falling out and prevent water from being scattered.
The water supply assembly comprises an outer hose 11 for guiding water
supplied from an external water tap or the like to the washing machine, a
water
supply valve 12 connected to the outer hose 11 to control the supply of water,
and a
water supply hose 13 connecting the water supply valve 12 and the detergent
supply
unit 30. The water supply valve 12 and the water supply hose 13 form a water
supply flow path through which water is supplied.
The detergent supply unit 30 is disposed on the water supply flow path. The
detergent supply unit 30 comprises a detergent box housing 31 installed to
communicate with the water supply hose 30, a detergent box 32 detachably
accommodated in the detergent box housing 31, and a detergent box cover fixed
to
the detergent box housing 31 and disposed on the top surface of the detergent
box
32 to spray water.
The detergent box housing 31 is installed at a detergent box installation part
formed at one side of the top cover 3.
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The detergent box 32 is coupled to the detergent box housing 31 so that a
user can take it out from the detergent box housing 31 in order to put
detergent
therein. The detergent box 32 may be coupled to the detergent box housing 31
so
as to be slidable back and forth. At least part of the rear surface of the
detergent
box 32 is opened, so that detergent can be introduced during water supply,
along
with water, into the detergent box housing 31 through the rear surface of the
detergent box 32.
The drain assembly 20 comprises a first drain hose 21 connected to the drain
port 26 formed on the bottom surface of the outer tub 4, a drain pump housing
24
including a drain pump for pumping water, and a second drain hose 25 connected
to
the drain pump housing 24 and draining the water pumped by the drain pump out
of
the cabinet 2. A drain motor for driving the drain pump is interposed within
the drain
pump housing 24.
The drain assembly 20 may be disposed between the outer tub 4 and the
base 5.
FIG. 3 is a perspective view showing an installation structure of a drain hole
cap shown in FIG. 1, FIG. 4 is an enlarged perspective view of the drain hole
cap
shown in FIG. 3, FIG. 5 is a cross-sectional view showing part A of FIG. 2,
and FIG.
6 is a cross-sectional view comparing the presence and absence of a drain port
cap.
Referring to FIG. 3, a shaft through hole 4b, through which a rotation shaft
8a
of the motor 9 passes, is formed at the center of the bottom surface of the
outer tub
4.
Also, a concave groove 4a, which is stepped downward, is formed on the
bottom surface of the outer tub 4, and a drain hole 26 which is formed in the
bottom
surface of the concave groove 4a for draining washing water temporarily stored
within the outer tub 4.
The concave groove 4a may have a heater (not shown), etc mounted thereon
for heating washing water. A heater installation part 4c for installing the
heater (not
shown) is formed at one side of the concave groove 4a.
A cross-section of the drain hole 26 may be circular, and protruded downward
so as to connect the first drain hose 21 thereto.
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The washing machine according to the first exemplary embodiment of the
present invention comprises a silencer which is formed for covering a vertical
top of
the drain hole 26 and for preventing noise generated during drainage.
The silencer comprises a drain hole cap 50 for limiting a space over the drain
hole and allowing the top of the drain hole 26 to be always filled with
washing water.
The drain hole cap 50 is formed for going through the drain hole 26 in the top
of the drain hole 26 and for covering the upper space of the drain hole 26 in
the
vertical direction.
Referring to FIG. 4, the drain hole cap 50 comprises an exit part 51 which is
formed to be opened so as to be connected with the drain hole 26 and to
discharge
washing water, a cover part 52 which is disposed to be separated from the exit
part
51 to a vertical direction with the predetermined distance, and a connection
part 53
which connects the exit part 51 and the cover part 52.
The drain hole cap 50 may be inserted into the drain hole 26, or may be fixed
by a fixing member as a bolt.
A description of this exemplary embodiment will be given only with respect to
the exit part 51 formed in a ring shape and adapted to be press fit into the
drain hole
26.
The cover part 52 has a disc shape, and a cross-sectional area of the cover
part 52 may be larger than or equal to the cross-sectional area of the drain
hole 26.
That is, it is preferred that the cover part 52 fully covers the upper space
over the
drain hole 26.
The connection part 53 may have a bar shape, and may be provided in plural,
spaced apart from each other at the predetermined interval.
The drain hole cap 50 is provided with an entrance part 54 formed at a lateral
side thereof so that the washing water in the outer tub 4 can be introduced in
a
lateral direction. The gaps among a plurality of connection parts 53 form the
entrance part 54.
A top end of the drain hole cap 50 is lower than a top end of a lateral side
of
the concave groove 4a. That is, it is preferred that the up-down length (I) of
the drain
hole cap 50 is shorter than the depth (d) of the concave groove 4a, or the top
end of
the drain hole cap 50 is not exposed to an upper side of the concave groove
4a.
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The cover part 52 of the drain hole cap 50 has to be disposed lower than the
top end of the lateral side of the concave groove 4a so that the inside of the
drain
hole cap 50 is always filled with washing water during drainage.
An operational effect of the thus-constructed washing machine according to
the first exemplary embodiment of the present invention will be described
below.
When the drain pump is put into operation, the washing water in the outer tub
4 is pumped by the drain pump, and sequentially passes through the drain hole
26,
the first drain hose 21, the drain pump 24, and the second drain hose 25, and
is
discharged out.
Referring to FIG. 6, if there is no drain hole cap 50, the pressure of the top
of
the drain hole 26 is lowered due to a difference between an amount of actual
drainage and an amount of pumping in an early stage of drainage. If the
pressure of
the top of the drain hole 26 is lowered, a vortex is generated as washing
water
rotates and an empty space not filled with water is formed in the top of the
drain hole
26. As air enters through such an empty space, abnormal noise may be generated
due to an air layer.
On the other hand, if there is the drain hole cap 50, the cover part 52 of the
drain hole cap 50 limit the upper space apart from the top of the drain hole
26 in the
vertical direction. That is, the cover part 52 of the drain hole cap 50 covers
the
upper space over the drain hole 26.
When drainage begins, the washing water around the drain hole cap 50
gathers towards the drain hole cap 50 along the bottom surface of the outer
tub 4.
The washing water gathered towards the drain hole cap 50 flows to the drain
hole 26 through the entrance part 54 formed at the lateral side of the drain
hole cap
50.
The washing water flown into the drain hole cap 50 through the entrance part
54 of the drain hole cap 50 fills the inside of the drain hole cap 50. Also,
the upper
space over the drain hole 26 is always filled with the washing water.
Accordingly, the empty space over the drain hole 26 is eliminated, and hence
air is not introduced into the drain hole 26.
Even when the amount of drainage is small, as in an early stage of drainage
or during intermittent dehydration, the top of the drain hole 26 is always
filled with
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washing water. Therefore, the pressure of the top of the drain hole 26 is not
lowered, and introduction of air into the drain hole 26 is prevented. As no
air is
introduced, this prevents the generation of abnormal noise due to an air
layer, thus
contributing to a quiet operation of the washing machine. Moreover, when air
introduction is prevented, pumping performance can be improved.
FIG. 7 is a perspective view of a drain hole cap according to a second
exemplary embodiment of the present invention.
Referring to FIG. 7, the construction and operation of the drain hole cap 100
of the washing machine according to the second exemplary embodiment of the
present invention are the same as those in the first exemplary embodiment,
except
that the drain hole cap 100 comprises an exit part 101 which is to be opened
so as
to be connected with the drain hole 26 and to discharge washing water, a cover
part
102 for covering the upper space over the drain hole 26, and an entrance part
103
for connecting the exit part 101 and the cover part 102 and introducing the
washing
water in the outer tub 4, and a plurality of intake holes 104 are formed in
the
entrance part 103 to introduce the washing water in the outer tub 4 and,
therefore, a
detailed description thereof will be omitted.
The drain hole cap 100 is shaped of a cylinder and the bottom surface of the
drain hole cap 100 is opened, and the plurality of intake holes 104 has a
circular
shape and are disposed apart from each other at predetermined intervals.
The washing water in the outer tub 4 is introduced into the drain hole cap 100
through the plurality of intake holes 104, and then discharged through the
exit part
101 and the drain hole 26. At this time, since the cover part 102 covers the
upper
space over the drain hole 26 and the washing water is discharged after being
filled
inside the drain hole cap 100, abnormal noise generated during drainage can be
reduced.
FIG. 8 is a cross-sectional view of a washing machine according to a third
exemplary embodiment of the present invention, FIG. 9 is a perspective view
showing part B of FIG. 8, FIG. 10 is a perspective view of a silencer shown in
FIG. 9,
and FIG. 11 is a cross-sectional view taken along line V-V of FIG. 9.
Referring to FIGS. 8 to 11, the construction and operation of the silencer of
the washing machine according to the third exemplary embodiment of the present
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invention are the same as those in the first exemplary embodiment, except that
the
silencer comprises a plate shaped drain hole cover 200 which is disposed over
the
drain hole 26 so as to be spaced apart from the drain hole 26 with a
predetermined
distance in a vertical direction and covers the upper space over the drain
hole 26
and, therefore, a detailed description thereof will be omitted.
The washing machine further comprises a heater 160 which is disposed over
the drain hole and heats washing water.
A heater mounting groove 161 for mounting the heater 160 thereon is formed
" on the bottom surface of the outer tub 4. While the heater mounting groove
161 is
described as a concave shape, the present invention is not limited thereto and
the
heater 160 may be fixed to one side of the outer tub 4 without forming the
heater
mounting groove 161.
The plate shaped drain hole cover 200 according to the third exemplary
embodiment of the present invention is disposed between the heater 160 and the
drain hole 26.
The plate shaped drain hole cover 200 comprises a connection part 201
which is fixed to the outer tub 4 and a cover part 202 which is extended from
the
connection part 201 and covers the drain hole 26.
A fixing groove (not shown) may be formed on the outer tub 4 to fix the
connection part 201 thereto. The connection part 201 may be fixed to the
fixing
groove (not shown) by a member (not shown) such as a bolt.
The connection part 201 is provided with fixing holes 201 for fixing the bolt
(not shown).
The cover part 202 is disposed not on the same plane as the connection part
201, but rather on a different plane from that of the connection part 201.
That is, the
cover part 202 is disposed in the heater mounting groove 161, and the
connection
part 201 is bent upward from the cover part 202 and disposed on the bottom
surface
of the outer tub 4.
The cover part 202 may be disposed to cover any part of the upper space
over the drain hole 26. The cover part 202 may be disposed to cover a half of
the
upper space over the drain hole 26 or the entire upper space over the drain
hole 26.
At this time, the cover part 202 is spaced apart from the top of the drain
hole 26 with
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a predetermined distance in the vertical direction. Therefore, even if the
cover part
202 covers the upper space over the drain hole 26, this does not obstruct
drainage.
As pointed out above, the cover part 202 of the plate shaped drain hole cover
200 limits the upper space over the drain hole 26. Thus, in the case of
drainage of
washing water, drainage is carried out as washing water is sufficiently filled
between
the cover part 202 and the drain hole 26.
Accordingly, the generation of a vortex over the drain hole 26 is prevented
and no air is introduced, thus reducing abnormal noise during drainage.
FIG. 12 is a plan view of a silencer according to a fourth exemplary
embodiment of the present invention, FIG. 13 is a perspective view of the
silencer
shown in FIG. 12, and FIG. 14 is a cross-sectional view taken along line I-1
of FIG.
12.
Referring to FIGS. 12 to 14, the construction and operation of the silencer of
the washing machine according to the fourth exemplary embodiment of the
present
invention are the same as those in the first exemplary embodiment, except that
the
silencer comprises a plate shaped drain hole cover 300 which is formed so as
to
cover the upper space over the drain hole 26 and the plate shaped drain hole
cover
300 is disposed over the heater 160 and, therefore, a detailed description
thereof will
be omitted.
The plate shaped drain hole cover 300 comprises a heater connection part
301 which is mounted on the heater 160 and a cover part 302 which is extended
from the heater connection part 301 and covers the upper space over the top of
the
drain hole 26.
The heater connection part 301 has a shape corresponding to one side
surface of the heater 160 so as to be mounted on the heater 160. This
exemplary
embodiment will be described with respect to the heater 160 having a circular
cross
section and the heater connection part 301 having a semi-circular cross
section.
However, the present invention is not limited thereto but the heater
connection part
301 may have various shapes corresponding to the shape of the heater 160.
The heater connection part 301 may only be mounted on the heater 160 or
may be fixed by a fixing member. For example, the heater connection part 301
may
comprise an engaging protrusion (not shown) for engaging the heater connection
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part 301 after the heater connection part 301 is mounted on the heater 160.
The
engaging protrusion may have a ring shape, but the present invention is not
limited
thereto and may comprise all structures that can be fixed to the heater 160.
The heater connection part 301 may be formed in plural number and mounted
on a plurality of positions of the heater 160. This exemplary embodiment will
be
described with respect to the case where two heater connection parts 301 are
provided at both left and right sides of the cover part 302.
The cover part 302 may be disposed to cover any part of the upper space
over the drain hole 26. The cover part 302 may be disposed to cover a half of
the
upper space over the drain hole 26 or the entire upper space over the drain
hole 26.
This exemplary embodiment will be described with respect to the case where the
cover part 302 fully covers the upper space over the drain hole 26.
The plate shaped drain hole cover 300 is disposed over the heater 160 and is
disposed apart from the drain hole 26 by a predetermined distance in a
vertical
direction. Therefore, even if the cover part 302 of the plate shaped drain
hole cover
300 covers the upper space over the drain hole 26, this does not obstruct
drainage.
As pointed out above, the cover part 302 of the plate shaped drain hole cover
300 limits the upper space over the drain hole 26. Thus, in the case of
drainage of
washing water, drainage is carried out as washing water is sufficiently filled
between
the cover part 302 and the drain hole 26.
Accordingly, the generation of a vortex above the drain hole 26 is prevented
and no air is introduced, thus reducing abnormal noise during drainage.
FIG. 15 is a longitudinal cross-sectional view of a washing machine according
to a fifth exemplary embodiment of the present invention, FIG. 16 is a view
showing
part C of FIG. 15, and FIG. 17 is a plan view showing a heater cover shown in
FIG.
16.
Referring to FIGS. 15 to 17, the construction and operation of the washing
machine according to the fifth exemplary embodiment of the present invention
are
the same as those in the first exemplary embodiment, except that the washing
machine comprises a heater cover 400 which is disposed on the heater mounting
groove 161 so as to cover the top of the heater 160 and fully covers the upper
space
over drain hole 26 and, therefore, a detailed description thereof will be
omitted.
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The heater mounting groove 161 is formed concave on the bottom surface of
the outer tub 4. The heater 160 is disposed at the heater mounting groove 161.
The drain hole 26 is formed at one lower part of the heater mounting groove
161, and the heater 160 is disposed above the drain hole 26.
The heater cover 400 may be shaped of a plate, and may be made of a metal
having heat resistance to endure heat generated in the heater 160.
The heater cover 400 covers the heater mounting groove 161, and is placed
flat with respect to the bottom surface of the outer tub 4. In the case that
the bottom
surface of the outer tub 4 and the heater mounting groove 161 are stepped, the
depth of water reserved in the outer tub 4 changes depending on position.
Thus, an
alpha water stream, which causes washing water to rise between the inner tub 6
and
the outer tub 4 by rapid rotation of the inner tub 6, may not be properly
formed.
In this exemplary embodiment, the heater cover 400 is disposed to cover the
top of the heater mounting groove 161 and arranged flat with respect to the
bottom
surface of the outer tub 4, thereby eliminating a stepped part of the bottom
surface of
the outer tub 4.
As the stepped part of the bottom surface of the outer tub 4 is eliminated by
means of the heater cover 400, the alpha water stream is properly formed, thus
improving washing performance.
The heater cover 400 may be fixed to the bottom surface of the outer tub 4 by
a fixing member. The heater cover 400 is provided with a plurality of fixing
holes
401, and fixed by a fixing member such as a bolt (not shown).
Referring to FIG. 17, the heater cover 400 is provided with a heater cover
hole 402 for emitting heat generated from the heater 160 and draining washing
water.
At least two heater cover holes 402 may be formed. This exemplary
embodiment will be described with respect to the case where there are two
heater
cover holes 402.
The two heater cover holes 402 may have different shapes and sizes from
each other. This exemplary embodiment will be described with respect to the
heater
cover holes 402 respectively having a circular shape and a semi-circular
shape. The
heater cover holes 402 may be larger than or equal to the drain hole 26.
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The heater cover holes 402 are formed at a position which does not overlap
the drain hole 26 in the vertical direction.
The heater cover holes 402 and the drain hole 26 are not disposed in a line
because the heater cover 400 has to fully cover the upper space over the drain
hole
26.
The circumferences of the heater cover holes 402 is disposed to be
separated from the circumference of the drain hole 26 to the vertical and
horizontal
direction with the predetermine distance.
The horizontal distance (t) between the circumference of one of the heater
cover holes 402 arranged closer to the drain hole 26 and the drain hole 26
preferably
exceeds 0.
When drainage begins, the washing water in the outer tub 4 is introduced into
the heater mounting groove 161 through the heater cover holes 402 and then
introduced into the drain hole 26.
Since the heater cover 400 covers the upper space over the drain hole 26,
the washing water is drained after filling the upper space over the drain hole
26.
That is, even in an early stage of drainage or when the amount of drainage
flow is small, the washing water fills the drain hole 26, thus preventing the
pressure
of the top of the drain hole 26 from being lowered. Accordingly, no vortex is
generated in the drain hole 26 and no air is introduced, thereby preventing
abnormal
noise caused by air introduction. This can contribute to a quiet operation of
the
washing machine, and improve pumping performance because of the prevention of
air introduction.
While specific embodiments have been described and illustrated, such
embodiments should be considered illustrative only and not as limiting the
invention
as defined by the accompanying claims.
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