U.S. patent application number 11/152786 was filed with the patent office on 2005-12-22 for drum-type washing machine.
This patent application is currently assigned to Samsung Electronics Co., Ltd.. Invention is credited to Georgiy, Severinets, Kang, Sung Wook, Kim, Seon Goo.
Application Number | 20050279142 11/152786 |
Document ID | / |
Family ID | 34941343 |
Filed Date | 2005-12-22 |
United States Patent
Application |
20050279142 |
Kind Code |
A1 |
Kim, Seon Goo ; et
al. |
December 22, 2005 |
Drum-type washing machine
Abstract
A drum-type washing machine including a housing, a water tub
installed in the housing to contain wash water, a rotating tub
rotatably installed in the water tub to rotate upon receiving a
rotating force via a rotating shaft, a stator fixedly mounted to
the water tub having an annular shape to allow the rotating shaft
to penetrate therethrough, and a rotor mounted to the rotating
shaft to rotate along with the rotating tub by interaction with the
stator. The rotor has protrusions at an outer end thereof with
protrusions having a predetermined height, and the protrusions
being formed with communication holes communicating the inside and
outside of the rotor with each other.
Inventors: |
Kim, Seon Goo; (Suwon-si,
KR) ; Kang, Sung Wook; (Seoul, KR) ; Georgiy,
Severinets; (Suwon-si, KR) |
Correspondence
Address: |
STAAS & HALSEY LLP
SUITE 700
1201 NEW YORK AVENUE, N.W.
WASHINGTON
DC
20005
US
|
Assignee: |
Samsung Electronics Co.,
Ltd.
Suwon-si
KR
|
Family ID: |
34941343 |
Appl. No.: |
11/152786 |
Filed: |
June 15, 2005 |
Current U.S.
Class: |
68/24 ; 68/133;
68/140; 68/58 |
Current CPC
Class: |
D06F 37/304
20130101 |
Class at
Publication: |
068/024 ;
068/058; 068/140; 068/133 |
International
Class: |
D06F 037/30 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 16, 2004 |
KR |
10-2004-0044323 |
Claims
What is claimed is:
1. A drum-type washing machine comprising: a housing; a water tub
installed in the housing to contain wash water; a rotating tub
rotatably installed in the water tub to rotate upon receiving a
rotating force; a rotating shaft to transfer the rotating force to
the rotating tub; a stator mounted on the water tub; a rotor
mounted on the rotating shaft; a plurality of protrusions
protruding from the rotor to increase a difference in flow rates of
air between an inside and an outside of the rotor; and a plurality
of communication holes formed in the protrusions and for fluid
communication of the air between the inside and outside of the
rotor.
2. The washing machine according to claim 1, wherein the rotor
comprises: a substantially circular hub portion rotating with the
rotating shaft; and a magnet mounting portion extending from an
outer edge of the hub portion to cover a radial outer side of the
stator, comprising magnets on an inside therein, wherein the
protrusions protrude from the hub portion.
3. The washing machine according to claim 2, wherein the
protrusions extend in a radially outward direction from a center of
the hub portion such that lateral opposite surfaces of the
protrusions push the air from the center of the hub portion in the
radially outward direction.
4. The washing machine according to claim 3, wherein the plurality
of the protrusions are radially formed at the hub portion.
5. The washing machine according to claim 1, wherein the
communication holes are formed at an uppermost portion of the
respective protrusions.
6. The washing machine according to claim 2, wherein the
communication holes are spaced outwardly from an outer surface of
the hub portion.
7. The washing machine according to claim 2, wherein the air inside
the rotor is discharged outside the rotor via the communication
holes.
8. A drum-type washing machine comprising: a rotor; a plurality of
protrusions on an outside of the rotor; and a plurality of holes
formed in the protrusions to pass air from an inside of the rotor
to an outside of the rotor.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Korean Patent
Application No. 2004-44323, filed on Jun. 16, 2004 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 drum-type washing
machine, and, more particularly, to a drum-type washing machine
having a driving motor adapted to rotate a rotating tub.
[0004] 2. Description of the Related Art
[0005] In general, drum-type washing machines wash laundry by
repeatedly performing washing and rinsing operations. Such a
drum-type washing machine is adapted to repeatedly raise and drop
the laundry, so that the laundry is washed due to the dropping
force.
[0006] The drum-type washing machine conventionally includes a
housing defining the outer appearance of the washing machine, a
cylindrical water tub installed in the housing to contain water, a
rotating tub rotatably installed in the water tub, and a driving
motor installed behind the water tub to generate a rotating force
necessary to rotate the rotating tub. The rotating force generated
from the driving motor is transmitted to the rotating tub via a
rotating shaft. As the rotating tub rotates upon receiving the
rotating force, the laundry, previously received in the rotating
tub, can be washed.
[0007] The driving motor includes an annular stator fixed to a rear
surface of the water tub, and an annular rotor disposed around the
stator and fixed to the rotating shaft. As the rotor rotates by
interaction of the stator and the rotor, the rotor rotates the
rotating shaft thereby rotating the rotating tub.
[0008] In this case, in order to externally emit heat generated by
the driving motor, the rotor of the driving motor is formed with a
plurality of communication holes. The communication holes allow the
inside and outside of the driving motor to communicate with each
other, thereby allowing the driving motor to be cooled by the
outside air introduced into the driving motor via the communication
holes.
[0009] In the above-described conventional drum-type washing
machine, generally, the driving motor is driven at a low speed in a
wash cycle, and is driven at a high speed in a spin-dry cycle.
During the low speed driving of the driving motor, namely, in the
wash cycle, only a small amount of the outside air is introduced
into the driving motor via the communication holes. This is because
of a low rotation speed of the rotor, and results in poor cooling
efficiency of the driving motor.
SUMMARY OF THE INVENTION
[0010] Accordingly, it is an aspect of the present invention to
provide a drum-type washing machine for improving cooling
efficiency of a driving motor thereof.
[0011] Additional aspects and/or advantages of the invention will
be set forth in part in the description which follows and, in part,
will be apparent from the description, or may be learned by
practice of the invention.
[0012] The forgoing and/or other aspects are achieved by providing
a drum-type washing machine including: a housing; a water tub
installed in the housing to contain wash water; a rotating tub
rotatably installed in the water tub to rotate upon receiving a
rotating force via a rotating shaft, to transfer the rotating force
to the rotating tub; a stator mounted on the water tub; a rotor
mounted on the rotating shaft; a plurality of protrusions
protruding from the motor to increase a difference in air flow
rates between an inside and an outside of the rotor; and a
plurality of communication holes formed at the protrusions and for
fluid communication of the inside and outside of the rotor.
[0013] The rotor may include a substantially circular hub portion
rotating with the rotating shaft; and a magnet mounting portion
extending from an outer edge of the hub portion to cover a radial
outer side of the stator, including magnets on an inside therein,
wherein the protrusions protrude from the hub portion.
[0014] The protrusions may extend radially and outwardly from a
center of the hub portion such that lateral opposite surfaces of
the protrusions push air from the center of the hub portion in a
radially outward direction.
[0015] The plurality of the protrusions may be radially formed at
the hub portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] These and/or other aspects and advantages of the invention
will become apparent and more easily appreciated from the following
description of the embodiment, taken in conjunction with the
accompanying drawings of which:
[0017] FIG. 1 is a side sectional view illustrating a drum-type
washing machine in accordance with an embodiment of the present
invention;
[0018] FIG. 2 is an enlarged view of circle 11 shown in FIG. 1;
and
[0019] FIG. 3 is an exploded perspective view illustrating the
installation structure of a driving motor employed in the drum-type
washing machine in accordance with the embodiment of the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0020] Reference will now be made in detail to the embodiment of
the present invention, an example of which is illustrated in the
accompanying drawings, wherein like reference numerals refer to the
like elements throughout. The embodiment is described below to
explain the present invention by referring to the figures.
[0021] FIG. 1 is a side sectional view illustrating a drum-type
washing machine in accordance with the embodiment of the present
invention. As shown in FIG. 1, the drum-type washing machine
includes a housing 10 defining the outer appearance of the washing
machine, a water tub 20 suspended in the housing 10 and adapted to
contain wash water, and a cylindrical rotating tub 30 rotatably
installed in the water tub 20 and formed at a peripheral wall
thereof with a plurality of through-holes 31. Reference numeral 32
denotes lifters adapted to raise laundry.
[0022] Openings are provided at respective front ends of the water
tub 20 and the rotating tub 30 to allow the laundry to be put into
or taken out of the rotating tub 30. A door 11 is hingably mounted
to a front wall of the housing 10, to open and close the openings
of the water tub 20 and the rotating tub 30.
[0023] Installed at the top of the housing 10 are a water supply
pipe 12 to receive wash water from an external water supply source,
a detergent container 13 to contain detergent, and mix the
detergent with the wash water supplied via the water supply pipe
12. A drain pump 14 and a drain hose 15 are installed at the bottom
of the housing 10, in order to externally drain the wash water
after completion of a wash cycle.
[0024] The drum-type washing machine further includes a driving
motor 40 to generate a rotating force required to rotate the
rotating tub 30, and a rotating shaft 43 (FIG. 2) which is
connected at one end thereof to the driving motor 40, and at the
other end thereof to the rotating tub 30, and to transmits the
rotating force from the driving motor 40 to the rotating tub
30.
[0025] As shown in FIG. 2, the driving motor 40 includes a stator
41 and a rotor 42. The stator 41 is fixedly mounted to the water
tub 20, and has an annular shape for allowing the rotating shaft 43
to penetrate therethrough and be installed therein. The stator 41
generates a magnetic field upon receiving a power supply voltage.
The rotor 42 has magnets 42a annularly disposed around the stator
41, and interacts with the stator 41 to rotate the rotating shaft
43 centrally fitted therein.
[0026] Referring to FIG. 3, the stator 41, taking the annular form,
is provided at a circumferential surface thereof with a plurality
of protruding teeth 41b having respective coils 41a wound thereon,
such that it can generate a magnetic field as a power supply
voltage is applied to the coils 41a. The rotor 42 further has a
circular hub portion 42b adapted to fixedly install the rotating
shaft 43 in the center thereof, and a magnet mounting portion 42c.
The magnet mounting portion 42c annularly extends from an outer
edge of the circular hub portion 42b to cover the radial outer side
of the stator 41, thereby allowing the magnets 42a to be annularly
disposed at the radial outer side of the stator 41.
[0027] In the above-described drum-type washing machine, in order
to achieve effective cooling of the driving motor 40, the hub
portion 42b is provided with a plurality of elongated protrusions
42d having a predetermined height. The protrusions 42d respectively
have communication holes 42e formed at the uppermost portions
thereof and allow the inside and outside of the rotor 42 to
communicate with each other.
[0028] In the driving motor 40, since the stator 41 is disposed
inside the rotor 42, the volume of an air flow space defined in the
rotor 42 is small, and thus the inside of the rotor 42 has a
relatively high flow resistance. On the contrary, the outside of
the rotor 42 is open and thus has a low flow resistance. As a
result, the air outside of the hub portion 42b flows at a higher
flow rate than the air inside of the rotor 42. However, when the
air is in contact with an outer surface of the hub portion 42b,
there is a significant frictional force between the air and the
outer surface. This frictional force reduces the flow rate, so that
the net difference between the flow rates inside and outside the
rotor 42 is reduced. Specifically, the flow rate outside the rotor
is only slightly greater than that of the air inside of the rotor
42.
[0029] Therefore, the protrusions 42d and the communication holes
42e formed therein are included to increase this pressure
difference that would otherwise only be slight. The communication
holes 42e are disposed at the ends of the protrusions 42d, and are
therefore spaced away from the outer surface of the hub portion
42b. Thus, the air passing through the communication holes 42e is
less influenced by friction and flows faster as compared to the air
in contact with the outside of the hub portion 42b. The increased
flow rate through the holes 42a causes flow rates of the air inside
and outside of the communication holes 42e to differ greatly from
one another. This results in an increase in pressure difference
between the air inside of the rotor 42, having a relatively low
flow rate, and the air outside of the rotor 42, having a relatively
high flow rate, according to Bernoulli's theorem. Thereby, the air
inside of the rotor 42, having a relatively high pressure, can be
easily discharged to the outside of the rotor 42, in a relatively
low pressure state, via the communication holes 42e.
[0030] Furthermore, in the present embodiment, since a plurality of
the elongated protrusions 42d are formed at the hub portion 42b
such that they extend in a radial outward direction, lateral
opposite surfaces of the respective protrusions 42d serve as a fan
adapted to push the air, in contact with the outer surface of the
rotor 42, in the radial outward direction. This increases the flow
rate of the air in contact with the outer surface of the hub
portion 42b, resulting in an increased flow rate difference between
the inside and outside of the rotor 42.
[0031] As is apparent from the above description, a drum-type
washing machine according to the embodiment of the present
invention includes a driving motor, which is designed in such a
fashion that a rotor thereof is provided with a plurality of
protrusions adapted to increase a difference in air flow rates
between the inside and outside of the rotor, such that the air
inside of the rotor, having a relatively low flow rate, has a
higher pressure than the air outside of the rotor, having a
relatively high flow rate, according to Bernoulli's theorem. This
allows the air inside of the rotor to be discharged to the outside
of the driving motor via communication holes perforated at the
protrusions by the large pressure difference, and consequently,
guaranteeing effective cooling of the driving motor even when the
driving motor is driven at a low speed.
[0032] Although an embodiment of the present invention has been
shown and described, it would be appreciated by those skilled in
the art that changes may be made in this embodiment without
departing from the principles and spirit of the invention, the
scope of which is defined in the claims and their equivalents.
* * * * *