U.S. patent application number 10/753494 was filed with the patent office on 2004-11-18 for variable damping type damper and washing machine having the same.
Invention is credited to Kim, Jae-Hyun, Park, Gwan-Ryong, Park, Seung-Chul.
Application Number | 20040226321 10/753494 |
Document ID | / |
Family ID | 33028874 |
Filed Date | 2004-11-18 |
United States Patent
Application |
20040226321 |
Kind Code |
A1 |
Park, Gwan-Ryong ; et
al. |
November 18, 2004 |
Variable damping type damper and washing machine having the
same
Abstract
A variable damping type damper and a washing machine having the
same comprise: a cylinder of which one side is provided with a
receiving space having a certain depth and another side thereof is
coupled to the cabinet or the tub; a rod of which one side is
relative-movably inserted into the receiving space of the cylinder
and another side thereof is coupled to the cabinet or the tub; a
guide bar provided at an end portion of the rod; a variable volume
frictional means expanded and contracted in itself by a difference
of flow amount introduced/exhausted into/from an inner space by
being coupled to the guide bar, and adhered/detached to/from an
inner circumferential surface of the receiving space of the
cylinder; a volume type slider performing a relative movement with
the variable volume frictional means by being slidably inserted
into the guide bar, for causing fluid flow inside the variable
volume frictional means; and a frictional member fixedly coupled to
the volume type slider for generating a frictional force with the
inner circumferential surface of the receiving space of the
cylinder. According to this, steady state vibration and transient
state vibration generated from a tub assembly during an entire
process for washing laundry are prevented from being transmitted to
a cabinet, thereby minimizing noise leaked to outside.
Inventors: |
Park, Gwan-Ryong; (Seoul,
KR) ; Kim, Jae-Hyun; (Seongnam, KR) ; Park,
Seung-Chul; (Gwangmyeong, KR) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
33028874 |
Appl. No.: |
10/753494 |
Filed: |
January 9, 2004 |
Current U.S.
Class: |
68/23.1 ; 68/140;
68/24; 68/58 |
Current CPC
Class: |
F16F 7/09 20130101; D06F
37/20 20130101 |
Class at
Publication: |
068/023.1 ;
068/024; 068/058; 068/140 |
International
Class: |
D06F 037/20 |
Foreign Application Data
Date |
Code |
Application Number |
May 15, 2003 |
KR |
2003-0031012 |
Claims
What is claimed is:
1. A variable damping type damper comprising: a cylinder provided
with a receiving space having a certain depth at one side thereof;
a rod relative-movably inserted into the receiving space of the
cylinder; a guide bar provided at the rod; a variable volume
frictional means expanded and contracted in itself by a difference
of flow amount introduced/exhausted into/from an inner space by
being coupled to the guide bar, and adhered/detached to/from an
inner circumferential surface of the receiving space of the
cylinder; a volume type slider performing a relative movement with
the variable volume frictional means by being slidably inserted
into the guide bar, for causing fluid flow inside the variable
volume frictional means; and a frictional member fixedly coupled to
the volume type slider for generating a frictional force with the
inner circumferential surface of the receiving space of the
cylinder.
2. The damper of claim 1, wherein the guide bar has a certain
length and has an outer diameter smaller than an outer diameter of
the rod.
3. The damper of claim 1, wherein a penetration hole connected to
the receiving space is formed at one side of a circumferential wall
of the cylinder.
4. The damper of claim 1, wherein an inner circumferential surface
of the receiving space of the cylinder is a frictional surface.
5. The damper of claim 1, wherein the variable volume frictional
means comprises: a cylindrical body having a certain outer diameter
and a length and having one side wall coupled to an end portion of
the guide bar thus to be volume-varied in itself; an inflow path
formed at one side of the cylindrical body; an outflow path having
less air flow amount than the inflow path and formed at another
side of the cylindrical body; a first valve for controlling a flow
of air introduced into the cylindrical body; and a first friction
ring coupled to an outer circumferential surface of the cylindrical
body.
6. The damper of claim 5, wherein a circumferential wall of the
cylindrical body is formed of a flexible membrane.
7. The damper of claim 5, wherein the inflow path is formed at a
side wall of a cylindrical body to which an end of a rod is
coupled, and the outflow path is formed at an opposite side wall of
the cylindrical body.
8. The damper of claim 7, wherein the inflow path is formed of a
plurality of penetration holes having the same inner diameter, and
the outflow path is formed of penetration holes having the number
less than the number of the penetration holes of the inflow
path.
9. The damper of claim 5, wherein the first valve is mounted at the
inflow path.
10. The damper of claim 5, wherein the first friction ring is
formed as a circular shape having a certain thickness and width,
and is expandable in a circumferential direction.
11. The damper of claim 5, wherein the first friction ring does not
receive a vertical force with an inner circumferential surface of
the receiving space of the cylinder when the cylindrical body is
not expanded in itself, and receives the vertical force when the
cylindrical body is expanded in itself.
12. The damper of claim 1, wherein the volume type slider
comprises: a cylindrical body having a certain outer diameter and
length and provided with an insertion hole for
penetration-inserting the guide bar at the center thereof; a
penetration path for penetrating the cylindrical body; and a second
valve for opening and closing the penetration path.
13. The damper of claim 1, wherein a frictional force due to a
relative movement between the frictional member and an inner
circumferential surface of the receiving space of the cylinder is
generated at the time of exceeding a preset vibration width.
14. The damper of claim 1, wherein a flexible tube for preventing
collision and air leakage is provided between the variable volume
frictional means and the volume type slider.
15. A washing machine comprising a cabinet having an inner space of
a predetermined shape; and a tub positioned in the cabinet and
filled with washing water, the washing machine provided with a
variable damping type damper, comprising: a cylinder of which one
side is provided with a receiving space having a certain depth and
another side thereof is coupled to the cabinet or the tub; a rod of
which one side is relative-movably inserted into the receiving
space of the cylinder and another side thereof is coupled to the
cabinet or the tub; a guide bar provided at an end portion of the
rod; a variable volume frictional means expanded and contracted in
itself by a difference of flow amount introduced/exhausted
into/from an inner space by being coupled to the guide bar, and
adhered/detached to/from an inner circumferential surface of the
receiving space of the cylinder; a volume type slider performing a
relative movement with the variable volume frictional means by
being slidably inserted into the guide bar, for causing fluid flow
inside the variable volume frictional means; and a frictional
member fixedly coupled to the volume type slider for generating a
frictional force with the inner circumferential surface of the
receiving space of the cylinder.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a variable damping type
damper and a washing machine having the same, and more
particularly, to a variable damping type damper capable of
minimizing a transmission of vibration to other components by
effectively absorbing steady state vibration and transient state
vibration by using a flow amount difference of air, and a washing
machine having the same.
[0003] 2. Description of the Conventional Art
[0004] Generally, a washing machine washes laundry by performing a
washing operation, a rinsing operation, and a dehydration
operation. Washing methods of the washing machine include a method
for washing laundry accordingly as vortex generated when a washing
bar having blades is rotated in the middle of a laundry basin
applies an impact to laundry, a method for washing laundry
accordingly as vortex generated when a rotation blade mounted at a
lower portion of a laundry basin is rotated applies an impact to
laundry, a method for washing laundry by an impact that laundry
drops by rotating a drum in which laundry is put in a horizontal
direction, and etc.
[0005] FIG. 1 is a frontal section view showing one embodiment of a
general washing machine.
[0006] As shown, the washing machine comprises a cabinet 100 having
an inner space of a predetermined shape; a tub 210 positioned in
the cabinet 100; a drum 220 rotatably inserted into the tub 210 and
through which laundry is introduced; a driving motor 230 mounted at
a rear surface of the tub 210 for rotating the drum 220; a spring
110 mounted between the cabinet 100 and an upper portion of the tub
210 for elastically supporting the tub 210; a damper 300 mounted
between the cabinet 100 and a lower portion of the tub 210 for
absorbing vibration; a water supply means (not shown) for supplying
washing water into the tub 210; a drain means (not shown) for
draining water inside the tub 210; and a door (not shown) for
opening and closing the drum 220.
[0007] The tub 210, the drum 220, and the driving motor 230
constitute one tub assembly 200, and the tub assembly 200 is
supported by the damper 300 and the spring 110.
[0008] For a washing operation in the washing machine, first, the
door is opened thus to put laundry into the drum 220, then the door
is closed, and detergent and washing water are put into the drum,
thereby rotating the drum 220 by a driving of the driving motor
230. After the washing operation, a rinsing operation is performed
and then washing water is drained by the drain means. Then, a
dehydration operation that washing water remaining on the laundry
is removed by a centrifugal force accordingly as the drum 220 is
rotated with a high speed is performed.
[0009] In a general washing machine, vibration is generated in the
tub assembly at the time of a washing operation or a dehydration
operation, and the vibration is absorbed by the spring 110 and the
damper 300 thus to be prevented from being transmitted to the
cabinet 100.
[0010] If vibration generated from the tub assembly 200 is
transmitted to the cabinet 100, great vibration noise is generated
at the cabinet 100, which causes uncomfortable feeling and degrades
a reliability of a product. Accordingly, minimizing vibration noise
is a great task.
[0011] FIG. 2 is a frontal section view showing a damper
constituting the washing machine. As shown, the damper 300
comprises a first body 310 having one side relative-movably coupled
to the tub 210 and having a frictional surface 311 of a cylindrical
shape at an inner portion of another side thereof; a second body
320 having one side relative-movably coupled to the cabinet 100 and
having another side inserted into the frictional surface 311 of the
first body 310; and a frictional member 330 fixedly coupled to the
second body 320 to be in contact with the frictional surface 311 of
the first body for generating a frictional force at the time of
moving. Also, a guide bush 340 for blocking a gap between the first
body 310 and the second body 320 is coupled to an inlet of the
frictional surface 311 of the first body 310.
[0012] The frictional member 330 is formed as ring shape having a
certain thickness and length, and a coupling groove 321 having a
certain depth and length is formed at an outer circumferential
surface of the second body 320 at one side thereof. The frictional
member 330 is inserted into the coupling groove 321 of the second
body. The outer circumferential surface of the frictional member
330 comes into contact with an inner circumferential surface of the
first body 310, that is, the frictional surface 311.
[0013] In the damper 300, when vibration generated from the tub
assembly 200 is transmitted, the second body 320 moves towards a
straight line direction and thereby the frictional member 330 is
moved together. According to this, a constant friction between the
outer circumferential surface of the frictional member 330 and the
frictional surface 311 of the first body is generated, thereby
absorbing vibration transmitted from the tub assembly 200.
[0014] However, in the washing machine, a degree of vibration
generated from the tub assembly 200 is different in an entire
process for washing laundry. That is, steady state vibration is
generated in a normal state at the time of a washing operation or a
dehydration operation, and transient state vibration is generated
in a process for reaching a normal dehydration speed at the time of
a dehydration operation. Therefore, by the damper 300 which
generates a constant frictional force, steady state vibration and
transient state vibration generated from the tub assembly 202 can
not be sufficiently absorbed, so that vibration generated from the
tub assembly 200 is transmitted to the cabinet 100 thus to generate
noise outwardly.
[0015] FIG. 3 is a frontal section view showing another embodiment
of the damper constituting the washing machine.
[0016] As shown, the damper comprises a first body 410 having a
frictional surface 411 of a cylindrical shape at an inner portion
at one side thereof; a second body 420 inserted into the frictional
surface 411 of the first body 410; a guide bar 430 having a certain
length and provided at one side of the first body 410; a slider 440
formed as a cylindrical shape and movably inserted into the guide
bar 430; a stopper 450 coupled to an end portion of the guide bar
430 for limiting a movement distance of the slider 440; a
frictional member 460 fixedly coupled to an outer surface of the
slider 440 thus to be adhered to the frictional surface 411 of the
first body; and springs 470 respectively positioned at both sides
of the slider 440.
[0017] An outer diameter of the guide bar 430 is smaller than an
inner diameter of the frictional surface 411 of the first body, and
the stopper 450 of a disc shape having a certain thickness has an
outer diameter smaller than the inner diameter of the frictional
surface 411 of the first body. One of the springs 470 which are
coil springs is positioned between one side surface of the slider
440 and the stopper 450, and the other is positioned between
another side surface of the slider 440 and an end surface of the
second body 420.
[0018] In the damper, when vibration transmitted form the tub
assembly 200 is less, that is, at the time of a normal state of
steady state vibration, the first body 410 and the slider 440
become integral under a state that the slider 440 is adhered to the
frictional surface 411. According to this, the slider 440 is
elastically supported by the springs 470 thus to be moved along the
guide bar 430, thereby absorbing vibration.
[0019] On the contrary, when transient state vibration is generated
in the process for reaching a normal dehydration speed during a
dehydration operation, the vibration is not sufficiently absorbed
thus to cause noise.
SUMMARY OF THE INVENTION
[0020] Therefore, an object of the present invention is to provide
a variable damping type damper and a washing machine having the
same, and more particularly, to a variable damping type damper
capable of minimizing a transmission of vibration to other
components by effectively absorbing steady state vibration and
transient state vibration by using a flow amount difference of air,
and a washing machine having the same.
[0021] To achieve these and other advantages and in accordance with
the purpose of the present invention, as embodied and broadly
described herein, there is provided a variable damping type damper
comprising: a cylinder provided with a receiving space having a
certain depth at one side thereof; a rod relative-movably inserted
into the receiving space of the cylinder; a guide bar provided at
the rod; a variable volume frictional means expanded and contracted
in itself by a difference of flow amount introduced/ exhausted
into/from an inner space by being coupled to the guide bar, and
adhered/detached to/from an inner circumferential surface of the
receiving space of the cylinder; a volume type slider performing a
relative movement with the variable volume frictional means by
being slidably inserted into the guide bar, for causing fluid flow
inside the variable volume frictional means; and a frictional
member fixedly coupled to the volume type slider for generating a
frictional force with the inner circumferential surface of the
receiving space of the cylinder.
[0022] To achieve these and other advantages and in accordance with
the purpose of the present invention, as embodied and broadly
described herein, there is also provided a washing machine
comprising a cabinet having an inner space of a predetermined
shape; and a tub positioned in the cabinet and filled with washing
water, the washing machine provided with a variable damping type
damper, comprising: a cylinder of which one side is provided with a
receiving space having a certain depth and another side thereof is
coupled to the cabinet or the tub; a rod of which one side is
relative-movably inserted into the receiving space of the cylinder
and another side thereof is coupled to the cabinet or the tub; a
guide bar provided at an end portion of the rod; a variable volume
frictional means expanded and contracted in itself by a difference
of flow amount introduced/ exhausted into/from an inner space by
being coupled to the guide bar, and adhered/detached to/from an
inner circumferential surface of the receiving space of the
cylinder; a volume type slider performing a relative movement with
the variable volume frictional means by being slidably inserted
into the guide bar, for causing fluid flow inside the variable
volume frictional means; and a frictional member fixedly coupled to
the volume type slider for generating a frictional force with the
inner circumferential surface of the receiving space of the
cylinder.
[0023] The foregoing and other objects, features, aspects and
advantages of the present invention will become more apparent from
the following detailed description of the present invention when
taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate embodiments of
the invention and together with the description serve to explain
the principles of the invention.
[0025] In the drawings:
[0026] FIG. 1 is a frontal section view showing one embodiment of a
general washing machine;
[0027] FIG. 2 is a frontal section view showing a damper
constituting the washing machine;
[0028] FIG. 3 is a frontal section view showing another embodiment
of the damper constituting the washing machine;
[0029] FIG. 4 is a frontal section view showing one embodiment of a
variable damping type damper according to the present
invention;
[0030] FIG. 5 is a sectional view showing the variable damping type
damper by a partial enlargement;
[0031] FIG. 6 is a frontal section view showing another embodiment
of the variable damping type damper according to the present
invention;
[0032] FIG. 7 is a frontal section view showing a washing machine
provided with the variable damping type damper according to the
present invention; and
[0033] FIGS. 8, 9, 10, and 11 are sectional views respectively
showing an operational state of the variable damping type damper
according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] Reference will now be made in detail to the preferred
embodiments of the present invention, examples of which are
illustrated in the accompanying drawings.
[0035] Hereinafter, a variable damping type damper and a washing
machine having the same will be explained with reference to
attached drawings.
[0036] FIG. 4 is a frontal section view showing one embodiment of a
variable damping type damper according to the present invention,
and FIG. 5 is a sectional view showing the variable damping type
damper by a partial enlargement.
[0037] As shown, the variable damping type damper according to the
present invention comprises: a cylinder 510 provided with a
receiving space 511 having a certain depth at one side thereof; a
rod 520 relative-movably inserted into the receiving space 511 of
the cylinder 510; a guide bar 530 provided at the rod 520; a
variable volume frictional means B expanded and contracted in
itself by a difference of flow amount introduced/exhausted
into/from an inner space by being coupled to the guide bar 530, and
adhered/detached to/from an inner circumferential surface of the
receiving space 511 of the cylinder 510; a volume type slider S
performing a relative movement with the variable volume frictional
means B by being slidably inserted into the guide bar 530, for
causing fluid flow inside the variable volume frictional means B;
and a frictional member 550 fixedly coupled to the volume type
slider S for generating a frictional force with the inner
circumferential surface of the receiving space 511 of the cylinder
510.
[0038] The cylinder 510 comprises a body portion 512 with a certain
length; a receiving space 511 of a cylindrical shape having a
certain depth in a longitudinal direction at one side of the body
portion 512; a penetration hole 513 connected to the receiving
space 511 at an outer circumferential wall of the body portion 512;
and a coupling portion 514 formed at another side of the body
portion 512. An inner circumferential surface of the receiving
space 511 forms a frictional surface 515.
[0039] A coupling portion 522 is formed at one side of the
cylindrical body portion 512 having a certain length and outer
diameter thus to constitute the rod 520.
[0040] The guide bar 530 has an outer diameter smaller than an
outer diameter of the cylindrical body portion 521 of the rod, and
has a certain length. The guide bar 530 is provided at the end of
the cylindrical body portion 521. The guide bar 530 can be
integrally formed with the rod 520, or can be separately
manufactured thus to be coupled to the rod 520.
[0041] The variable volume frictional means B comprises a
cylindrical body 560 having a certain outer diameter and a length
and having one side wall coupled to an end portion of the guide bar
530 thus to be volume-varied in itself; an inflow path 561 formed
at one side of the cylindrical body 560; an outflow path 562 having
less air flow amount than the inflow path 561 and formed at another
side of the cylindrical body 560; a first valve 570 for controlling
a flow of air introduced into the cylindrical body 560; and a first
friction ring 580 coupled to an outer circumferential surface of
the cylindrical body 560.
[0042] The cylindrical body 560 comprises a circumferential wall
portion 563 having a certain thickness and outer diameter; a first
side wall portion 564 for covering one side of the circumferential
wall portion 563; and a second side wall portion 565 for covering
another side of the circumferential wall portion 563. An end
portion of the guide bar 530 is coupled to the center of the first
side wall portion 564.
[0043] The circumferential wall portion 563 of the cylindrical body
560 is formed of a flexible membrane to be expanded.
[0044] The inflow path 561 is formed at the first side wall portion
564 of the cylindrical body, and the outflow path 562 is formed at
the second side wall portion 565 of the cylindrical body.
[0045] The inflow path 561 is formed of a plurality of penetration
holes penetrated at the first side wall portion 564, and inner
diameters of the penetration holes are the same. The outflow path
562 is formed of one penetration hole or a plurality of penetration
holes, a size of the penetration hole of the outflow path 562 is
the same as a size of the penetration hole of the inflow path 561,
and the number of the penetration holes of the outflow path 562 is
less than the number of the penetration holes o the inflow path
561. Also, an entire area of the inflow path 561 is larger than an
entire area of the outflow path 562, and shapes of the inflow path
561 and the outflow path 562 can be variously implemented.
[0046] The first valve 570 is mounted at the first side wall
portion 564 of the cylindrical body thus to open and close the
inflow path 561.
[0047] The first friction ring 580 is formed of a circular shape
having a certain thickness and width, and can be formed of a
material expandable in a circumferential direction. The first
friction ring 580 does not receive a vertical force with an inner
circumferential surface of the receiving space 511 of the cylinder
510 when the cylindrical body 560 is not expanded in itself, and
receives the vertical force when the cylindrical body 560 is
expanded in itself.
[0048] The volume type slider S comprises a cylindrical body 540
having a certain outer diameter and length and provided with an
insertion hole 541 for penetration-inserting the guide bar 530 at
the center thereof; a penetration path 542 for penetrating the
cylindrical body 540; and a second valve 590 for opening and
closing the penetration path 542.
[0049] The cylindrical body 540 of the volume type slider S
comprises a circumferential wall portion 543 having a certain
thickness and outer diameter; a first side wall portion 544 for
covering one side of the circumferential wall portion 543; and a
second side wall portion 545 for covering another side of the
circumferential wall portion 543. The insertion hole 541 is
penetratingly-formed at the center of the first side wall portion
544 and at the center of the second side wall portion 545,
respectively.
[0050] The penetration path 542 is constituted with a plurality of
penetration holes formed at the first side wall portion 544 of the
cylindrical body and a plurality of penetration holes formed at the
second side wall portion 545.
[0051] The second valve 590 is mounted at the second side wall
portion 545 of the cylindrical body thus to open and close the
penetration holes formed at the second side wall portion 545.
[0052] The volume type slider S is positioned between the variable
volume frictional means B and the rod 520, and a hermetic space A
is formed between the variable volume frictional means B and the
volume type slider S.
[0053] The frictional member 550 is formed as a ring shape having a
certain thickness and width. Under a state that the frictional
member 550 is coupled to the cylindrical body 540 of the volume
type slider, when a vibration width more than a preset degree is
transmitted to the frictional member 550 adhered to the frictional
surface 515 of the cylinder, that is, when a force more than a
preset degree is applied, the frictional member 550 performs a
relative movement with the frictional surface 515 of the cylinder
and thereby a frictional force is generated.
[0054] FIG. 6 is a frontal section view showing another embodiment
of the variable damping type damper according to the present
invention. The same reference numbers were given to the same parts
as the aforementioned variable damping type damper.
[0055] As shown, the variable damping type damper has the same
construction as the aforementioned variable damping type damper.
That is, constructions of the cylinder 510, the variable volume
frictional means B, the volume type slider S, and the frictional
member 550 are the same.
[0056] A flexible tube 600 is provided between the variable volume
frictional means B and the volume type slider S. The flexible tube
600 prevents collision generated when the variable volume
frictional means B and the volume type slider S perform a relative
movement, and prevents outflow of air.
[0057] FIG. 7 is a frontal section view showing a washing machine
provided with the variable damping type damper according to the
present invention.
[0058] As shown, the washing machine comprises: a cabinet 100
having an inner space of a predetermined shape; a tub assembly 200
positioned in the cabinet 100; a spring 110 for connecting an upper
portion of the tub assembly 200 and the cabinet 100; a cylinder 510
of which one side is provided with a receiving space 511 having a
certain depth and another side thereof is coupled to the tub
assembly 200; a rod 520 of which one side is relative-movably
inserted into the receiving space 511 of the cylinder and another
side thereof is coupled to the cabinet 100; a guide bar 530
provided at an end portion of the rod 520; a variable volume
frictional means B expanded and contracted in itself by a
difference of flow amount introduced/exhausted into/from an inner
space by being coupled to the guide bar 530, and adhered/detached
to/from an inner circumferential surface of the receiving space 511
of the cylinder; a volume type slider S performing a relative
movement with the variable volume frictional means B by being
slidably inserted into the guide bar 530, for causing fluid flow
inside the variable volume frictional means B; and a frictional
member 550 fixedly coupled to the volume type slider S for
generating a frictional force with the inner circumferential
surface of the receiving space 511 of the cylinder.
[0059] The tub assembly 200 comprises a tub 210 positioned in the
cabinet 100; a drum 220 rotatably inserted into the tub 210 and
through which laundry is put into; and a driving motor 230 mounted
at a rear surface of the tub 210 for rotating the drum 220.
[0060] One side of the cylinder 510 can be coupled to the cabinet
100, and one side of the rod 520 can be coupled to the tub assembly
200.
[0061] Also, a water supply means (not shown) for supplying washing
water into the tub 210, a drain means (not shown) for draining
washing water inside the tub 210, and a door (not shown) for
opening and closing the drum 220 are provided.
[0062] The cylinder 510, the rod 520, the guide bar 530, the
variable volume frictional means B, the volume type slider S, and
the frictional member 550 have the same constructions. Accordingly,
minute explanations for the variable damping type damper will be
omitted.
[0063] Hereinafter, effects of the variable damping type damper and
the washing machine having the same will be explained.
[0064] First, in case of the variable damping type damper, in a
process that steady state vibration is applied to the cylinder 510
from outside, the frictional surface 515 of the cylinder 510 and
the frictional member 550 are in a state of being adhered to each
other and a vertical force has not been applied between the first
friction ring 580 and the frictional surface 515 of the cylinder
510. According to this, the volume type slider S, the frictional
member 550, and the cylinder 510 become integral, so that the
volume type slider S moves along the guide bar 530, and the
variable volume frictional means B, the guide bar 530, and the rod
520 do not move.
[0065] At this time, as shown in FIG. 8, when the volume type
slider S moves towards the rod 520, a volume of the hermetic space
A between the volume type slider S and the variable volume
frictional member 550 is increased. According to this, by a
pressure difference, the first valve 570 of the variable volume
frictional means B is closed, at the same time the second valve 590
of the volume type slider S is opened, and external air is
introduced into the hermetic space A through the penetration path
542.
[0066] Also, as shown in FIG. 9, when the volume type slider S
moves towards the variable volume frictional means B, a volume of
the hermetic space A is decreased and a pressure is increased.
According to this, the first valve 570 of the variable volume
frictional means B is opened and the second valve 590 is closed, so
that air of the hermetic space A is exhausted outwardly through the
inflow path 561 and the outflow path 562. Herein, since a movement
of the volume type slider S is a little, air introduced into the
inflow path 561 of the variable volume frictional means is smoothly
exhausted through the outflow path 562 without a flow resistance of
fluid.
[0067] By said processes, steady state vibration transmitted to the
cylinder 510 or the rod 520 is absorbed.
[0068] Additionally, in a process that transient state vibration is
applied to the cylinder 510 from outside, the frictional surface
515 of the cylinder 510 and the frictional member 550 are in a
state of being adhered to each other and a vertical force has not
been applied between the first friction ring 580 and the frictional
surface 515 of the cylinder 510. According to this, the volume type
slider S, the frictional member 550, and the cylinder 510 become
integral, so that the volume type slider S moves along the guide
bar 530, and the variable volume frictional means B, the guide bar
530, and the rod 520 do not move.
[0069] At this time, as shown in FIG. 10, when the volume type
slider S moves with a great displacement towards the rod 520, a
volume of the hermetic space A between the volume type slider S and
the variable volume frictional member 550 is increased. According
to this, by a pressure difference, the first valve 570 of the
variable volume frictional means B is closed, at the same time the
second valve 590 of the volume type slider S is opened, and
external air is relatively much introduced into the hermetic space
A through the penetration path 542.
[0070] Also, as shown in FIG. 11, when the volume type slider S
moves with a great displacement towards the variable volume
frictional means B, a volume of the hermetic space A is relatively
decreased and a pressure is increased. According to this, the first
valve 570 of the variable volume frictional means B is opened and
the second valve 590 is closed, so that air of the hermetic space A
is introduced into the variable volume frictional means B through
the inflow path 561. A part of the air introduced into the variable
volume frictional means B is exhausted outwardly through the
outflow path 562, and by the rest air, the variable volume
frictional means B is expanded thus to be adhered to the frictional
surface of the cylinder 510.
[0071] That is, since the inflow path 561 of the variable volume
frictional means B is larger than the outflow path 562, when a
large amount of air is momentarily introduced into variable volume
frictional means B, all the introduced air are not exhausted
outwardly through the outflow path 562 thus to expand a volume of
the cylindrical body 560 of the variable volume frictional means.
According to this, the first friction ring 580 is adhered to the
frictional surface 515 of the cylinder thus to cause a frictional
force. A degree of the frictional force can be different by
controlling sizes of the inflow path 561 and the outflow path 562
of the variable volume frictional means B.
[0072] Accordingly as said processes are repeated, transient state
vibration transmitted to the cylinder 510 or the rod 520 is
absorbed.
[0073] Like this, the variable damping type damper absorbs both
steady state vibration and transient state vibration.
[0074] Meanwhile, in a case that the flexible tube 600 is provided
between the variable volume frictional means B and the volume type
slider S, air is prevented from being leaked outside the hermetic
space A thus to have a good responsiveness. Also, in a case that a
displacement of the cylinder 510 is great, collision between
components is prevented.
[0075] The washing machine is operated by a washing operation, a
rinsing operation, and a dehydration operation as a general
one.
[0076] In a process for reaching a dehydration speed of a high
speed under a normal state or for stopping a driving at the
dehydration speed of a normal state, transient state vibration is
generated from the tub assembly 200 and the vibration is
transmitted to the variable damping type damper 500. When transient
state vibration is transmitted to the variable damping type damper
500, as aforementioned, the variable damping type damper 500 is
operated in a transient state vibration mode thus to absorb
transient state vibration. According to this, a transmission of
transient state vibration generated from the tub assembly 200 to
the cabinet 100 is minimized.
[0077] Additionally, while a washing operation is performed or a
dehydration operation is performed at a dehydration speed of a
normal state, steady state vibration is generated from the tub
assembly 200 and the vibration is transmitted to the variable
damping type damper 500. When steady state vibration is transmitted
to the variable damping type damper 500, as aforementioned, the
variable damping type damper 500 is operated in a steady state
vibration mode thus to absorb steady state vibration. According to
this, a transmission of steady state vibration generated from the
tub assembly 200 to the cabinet 100 is minimized.
[0078] Like this, in the washing machine, both transient state
vibration and steady state vibration generated from the tub
assembly 200 during the entire operation are absorbed thus to
minimize vibration noise generated from the cabinet 100.
[0079] As aforementioned, the variable damping type damper
according to the present invention absorbs both steady state
vibration and transient state vibration transmitted from another
system by using a flow amount difference of air, thereby preventing
vibration from being transmitted to other components. Thus, a
reliability and a stability of a system to which the variable
damping type damper is applied can be enhanced.
[0080] Also, in the washing machine having the variable damping
type damper according to the present invention, transient state
vibration and steady state vibration generated from the tub
assembly 200 are prevented from being transmitted to the cabinet
100 during the entire process for washing laundry, thereby
minimizing vibration noise leaked to outside and thus enhancing a
reliability of a product.
[0081] As the present invention may be embodied in several forms
without departing from the spirit or essential characteristics
thereof, it should also be understood that the above-described
embodiments are not limited by any of the details of the foregoing
description, unless otherwise specified, but rather should be
construed broadly within its spirit and scope as defined in the
appended claims, and therefore all changes and modifications that
fall within the metes and bounds of the claims, or equivalence of
such metes and bounds are therefore intended to be embraced by the
appended claims.
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