KR102343900B1 - Laundry treating machine - Google Patents

Abstract

Laundry treatment apparatus according to an embodiment of the present invention, a cabinet; a drum accommodated inside the cabinet; a tub for accommodating the drum; and a dynamic absorber provided to absorb vibrations of the cabinet, wherein the dynamic absorber includes: a support plate coupled to the cabinet; a moving mass resting on the support plate; and a slider interposed between the mass body and the support plate to enable the mass body to reciprocate with damping due to frictional force on the plate.

Description

Laundry treating machine {Laundry treating machine}

The present invention relates to a laundry treatment device.

In the case of home appliances having a rotating drum inside, such as a washing machine or dryer, as the rotational speed (rpm) of the drum increases, the laundry put into the drum, that is, the horizontal excitation force is generated by the eccentricity of the load. do.

In particular, as in the spin-drying process, in the process of increasing the rotational speed of the drum, a transient vibration in which the horizontal vibration displacement of the washing machine cabinet rapidly increases at the resonant frequency point of the washing machine cabinet occurs. And, when the drum is constantly maintained at the maximum speed, a normal vibration in which the same vibration is constantly repeated occurs.

Due to such excessive vibration, the washing machine staggers in the left and right directions while the rotation speed of the drum increases. In addition, such excessive vibration appears more conspicuously in a stack type washing machine in which the washing machine is spaced apart from the ground.

For example, in the case of a small washing machine or a stack type washing machine stacked on the upper surface of an object for storing laundry, the vibration displacement of the excessive vibration is greater than that of a general washing machine placed directly on the installation surface, and the excessive vibration occurs during low-speed operation. That is, in the stack-type washing machine, the generation time of excessive vibration is earlier than in the washing machine placed directly on the floor.

In order to absorb such excessive vibration, a dynamic absorber is generally installed in the washing machine.

The dynamic absorber is a dynamic absorber using the principle of absorbing the vibration of the washing machine by vibrating in the horizontal direction with a phase 180 degrees opposite to the phase of the horizontal excitation force generated by the rotation of the drum.

In detail, when the drum rotates accelerated, as described above, an excitation force is generated in the horizontal direction by the rotation of the eccentric load (laundry). And, when the resonant frequency of the drum is reached while the rotational speed of the drum is increased, the washing machine cabinet performs harmonic vibration with a phase difference of 90 degrees from the excitation force at the resonance point.

In addition, at the resonance point, the dynamic absorber vibrates harmoniously with a phase difference of 90 degrees from the vibration of the washing machine cabinet. As a result, the vibration is canceled by vibrating in opposite directions with a 180 degree phase difference between the excitation force and the dynamic absorber, and as a result, the washing machine cabinet does not move.

The following US registered patent discloses a technology in which the dynamic absorber is provided in a washing machine.

The dynamic absorber disclosed in the prior art has a structure in which a frame is provided on a bottom surface of a casing of a washing machine, a viscoelastic member is placed on an upper surface of the frame, and a mass for absorbing vibration is placed on the upper surface of the viscoelastic member.

Such a dynamic absorber structure has the following problems.

First, since the viscoelastic member is placed on the bottom surface of the mass body, the load of the mass may continuously act on the elastic member, which may lead to damage and deterioration of the elastic member.

Second, when the mass vibrates in the horizontal direction, since the viscoelastic member absorbs the vibration by using a shear stress acting in the left and right directions, there is a disadvantage in that the excessive vibration cannot be effectively absorbed due to the low damping ratio.

Although it is described in the patent specification of the prior art that vibration can be effectively absorbed in the entire region of the rotation speed of the drum, the dynamic absorber disclosed in the prior art may have an effect of absorbing continuous oscillation. The ability to absorb transient vibrations in which the vibrational displacement suddenly increases is significantly reduced.

Third, since the shear stress alternately acts on the viscoelastic member, there is a disadvantage in that the possibility of damage to the viscoelastic member is increased and the lifespan is shortened.

Fourth, when the horizontal vibration acts on the washing machine to horizontally move the mass in the opposite direction to the vibration, the upper end of the elastic member moves in the horizontal direction and the elastic member is bent. As a result, there is a problem in that the mass body cannot swing in the left and right directions while maintaining a horizontal state for absorbing vibration. In other words, when the mass body swings in the left and right directions to absorb the lateral vibration, the left and right ends of the mass body are inclined downward due to the bending phenomenon of the elastic member. As a result, the horizontal vibration acting on the washing machine cannot be effectively absorbed.

US Registered Patent No. US8443636 (May 21, 2013)

The present invention has been proposed to improve the above problems.

Laundry treatment apparatus according to an embodiment of the present invention for achieving the above object, the cabinet; a drum accommodated inside the cabinet; a tub for accommodating the drum; and a dynamic absorber provided to absorb vibrations of the cabinet, wherein the dynamic absorber includes: a support plate coupled to the cabinet; a moving mass resting on the support plate; and a slider interposed between the mass body and the support plate to enable the mass body to reciprocate on the plate with damping due to frictional force, the slider comprising: a lower slider mounted on the support plate; It may include an upper slider that is mounted on the bottom surface of the mass and is slidably placed on the upper surface of the lower slider.
In addition, the laundry treatment apparatus according to an embodiment of the present invention, the cabinet; a drum accommodated inside the cabinet; a tub for accommodating the drum; and a dynamic absorber provided to absorb vibrations of the cabinet. including, wherein the dynamic absorber includes: a support plate seated on the cabinet; a mass resting on the support plate; and a damping member interposed between the mass body and the support plate, the mass body having damping due to frictional force on the plate, wherein the damping width of the dynamic reducer is 300 rpm ~ It is characterized in that it is within the range of 400rpm.

According to the laundry treatment apparatus according to the embodiment of the present invention having the configuration as described above, the following effects are obtained.

First, since the mass body is provided slidably on the support plate, the mass body can horizontally move in a phase opposite to the action direction of vibration generated in the cabinet, thereby improving vibration damping ability.

Second, since the mass body of the present invention is horizontally supported by a slider having a predetermined frictional force on the upper surface of the base plate, there is an advantage in that excessive vibration generated in the cabinet can be effectively absorbed.

Third, by appropriately adjusting the mass ratio of the mass body of the present invention and the laundry treatment device to which the mass body is mounted, there is an advantage in that a vibration absorption region (or absorption width) for absorbing excessive vibrations can be sufficiently secured. That is, there is an advantage in that the vibration reduction effect is improved by effectively covering the rotation frequency region of the drum in which the excessive vibration generated in the cabinet is generated.

Fourth, since only a unidirectional force acts on the elastic damper mounted on the side of the mass body, the life of the elastic damper is prolonged and the vibration absorption ability is improved. In other words, since normal stress acts on the elastic damper according to the embodiment of the present invention, the lifespan is longer and the vibration absorption ability is improved compared to the elastic damper of the prior art to which shear stress acts.

1 is a perspective view of a laundry treatment apparatus according to an embodiment of the present invention;
2 is an exploded perspective view showing an internal structure of a laundry treatment apparatus having a dynamic absorber according to an embodiment of the present invention;
FIG. 3 is a partial longitudinal cross-sectional view of the laundry treatment apparatus taken along line 3-3 of FIG. 1 .
4 is a perspective view of a dynamic reducer according to an embodiment of the present invention;
5 is an exploded perspective view of the dynamic absorber;
6 is a perspective view of a mass constituting a dynamic reducer according to an embodiment of the present invention;
7 is a perspective view of a support plate constituting a dynamic reducer according to an embodiment of the present invention;
8 is a plan perspective view of an upper slider constituting a slider according to an embodiment of the present invention;
Fig. 9 is a bottom perspective view of the upper slider;
10 is a plan perspective view of a lower slider constituting a slider according to an embodiment of the present invention;
11 is a bottom perspective view of the lower slider.
Fig. 12 is a longitudinal cross-sectional view taken along line 12-12 of Fig. 4;
13 is a front perspective view of an elastic damper according to an embodiment of the present invention;
14 is a bottom perspective view of the elastic damper.
Fig. 15 is a longitudinal cross-sectional view taken along line 15-15 of Fig. 7;
Fig. 16 is a longitudinal cross-sectional view taken along lines 16-16 of Fig. 7;
17 is a graph showing the vibration displacement of a laundry treatment apparatus equipped with a dynamic absorber.

Hereinafter, a laundry treatment apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.

[Definition of Terms]

First, terms to be described below are defined.

Damped oscillation (vibration) or transient oscillation (vibration), which will be described below, is a vibration in which the vibration displacement of the cabinet at the resonance point of the drum rapidly increases when the drum in which laundry is loaded rotates rapidly for rinsing or dehydration. is defined as meaning

And, the steady-state oscillation (vibration) or continuous oscillation (vibration) described below is defined as meaning a vibration that occurs continuously with a nearly constant vibration displacement while the drum is maintained at the maximum speed. do.

And, that the dynamic absorber according to an embodiment of the present invention improves or absorbs the transient or normal vibration means that the dynamic absorber eliminates or minimizes the vibration displacement of the transient or normal vibration, thereby minimizing the vibration of the cabinet. can be understood as

1 is a perspective view of a laundry treatment apparatus according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of the laundry treatment apparatus having a dynamic absorber according to an embodiment of the present invention, and FIG. 3 is 3-3 of FIG. It is a partial longitudinal cross-sectional view of the laundry treatment apparatus cut along the .

1 to 3 , in the embodiment of the present invention, the turbidity treatment apparatus 10 includes a cabinet 11 and a dynamic absorber ( 20), and a drum (not shown) accommodated in the cabinet 11 and a tub 16 for accommodating the drum.

In detail, the cabinet includes a front cabinet 111 , a side cabinet 112 , and a rear cabinet 113 . A top plate 12 is placed on the upper surface of the cabinet to cover the upper surface opening of the cabinet 11 .

In addition, a door 15 is rotatably coupled to the front cabinet 111 to put laundry into the drum. In addition, a detergent box 14 and a control panel 13 may be provided at an upper end of the front cabinet 111 .

In addition, the laundry treatment apparatus 10 may be placed directly on the installation surface, or may be placed on a separate stack W having a predetermined height h. The separate stack (W) may be an independent laundry device having a small volume, or may be a storage box for storing items including laundry, but is not limited thereto.

Meanwhile, the dynamic absorber 20 according to the embodiment of the present invention is seated on the upper surface of the cabinet 11 and is covered by the top plate 12 to block external exposure.

In detail, the dynamic absorber 20 includes a support plate 24 seated on the cabinet 11 , and a moving mass 21 placed movably in the horizontal direction on the upper surface of the support plate 24 , , a slider 22 interposed between a bottom surface of the mass body 21 and an upper surface of the support plate 24 to enable left and right movement of the mass body 21 , and a side surface of the mass body 21 and the support plate 24 . An elastic damper 23 interposed between the plates 24 may be included.

Here, the mass 21 may be defined as a mass that absorbs vibrations of the cabinet 11 by moving in a phase opposite to a horizontal excitation force generated by rotation of the drum having an eccentric load.

In addition, left and right ends of the support plate 24 are seated on top of the left and right side cabinets 112 . In addition, since the detergent box 14 and the control panel 13 are located on the inner upper side of the cabinet 11 , the dynamic absorber 20 is installed at the front end of the cabinet 11 to avoid interference with them. It may be located rearwardly spaced apart from the part.

For example, the horizontal distance between the front end of the support plate 24 and the front cabinet 111 may be set longer than the horizontal distance between the rear end of the support plate 24 and the rear cabinet 113 . have. However, the present invention is not necessarily limited thereto, and the dynamic absorber 20 may be located at the center of the upper surface of the cabinet 11 .

Hereinafter, the structure and function of the dynamic absorber 20 will be described in more detail with reference to the drawings.

4 is a perspective view of a dynamic reducer according to an embodiment of the present invention, and FIG. 5 is an exploded perspective view of the dynamic reducer.

4 and 5 , the dynamic absorber 20 according to the embodiment of the present invention includes the mass body 21 , the slider 22 , the elastic damper 23 , and the support plate 24 as described above. may include However, it should be noted that in some cases, the dynamic reducer 20 may be understood to mean the mass body 21 .

In detail, a part of the slider 22 is coupled to the bottom surface of the mass body 21 , and the other part is fixed to the top surface of the support plate 24 . And, the mass body 21 slides in the opposite direction (or opposite phase) to the vibration direction (or vibration phase) of the excitation force transmitted to the cabinet 11 on the support plate 24, so that the cabinet ( 11) absorbs the transmitted vibration.

In detail, when horizontal vibration is generated by the excitation force generated as the drum accelerates and rotates, the mass body 21 moves in a phase opposite to the phase of the excitation force and collides with the elastic damper 23, The elastic damper 23 absorbs an impact applied from the mass body 21 through elastic deformation.

Here, a predetermined frictional force acts on the slider 22 , and the frictional force acts as an attenuation of the dynamic reducer 20 . And, the damping of the dynamic absorber 20 acts as a variable that determines the vibration displacement of the transient vibration. In addition, the friction coefficient of the friction force determines the magnitude of the damping, and the greater the damping (or damping value), the better the ability of the dynamic absorber 20 to absorb excessive vibration.

Of course, since the elastic damper 23 also has damping for absorbing excessive vibration as well as elasticity (or rigidity), it affects the improvement of excessive vibration, but it can be said that it is significantly smaller than the damping caused by friction. Therefore, the elastic damper 23 can be said to be a damper that mainly affects the improvement of the normal vibration transmitted by the dynamic damper 20 to the cabinet 11 .

6 is a perspective view of a mass constituting a dynamic reducer according to an embodiment of the present invention.

Referring to FIG. 6 , the mass body 21 according to the embodiment of the present invention may be formed of a square plate made of a metal material including iron, but may be formed of a material other than iron.

In detail, a plurality of thin metal plates may be stacked on the mass body 21 , and the stacked metal plates may be fixed as a unit by a rivet unit 211 . And, the laminated metal plate may be 5-10 sheets, preferably 8 sheets, but is not limited thereto.

As another example, the mass body 21 may be a single metal plate having a predetermined thickness. In addition, the mass 21 may be a mass of 4-10 kg, preferably a mass of 6-8 kg, and more preferably a mass of 7 kg.

In addition, the corner portion 213 of the mass body 21 may be formed to be rounded with a predetermined curvature, but is not limited thereto. In addition, the rivet part 211 may be formed at four corners and a central part of the mass body 21 .

Meanwhile, a plurality of slider fastening holes 212 are formed in the mass body 21 , and the slider 22 is coupled to the slider fastening holes 212 .

In detail, the slider fastening holes 212 may form one group with the number corresponding to the fastening protrusions formed on the slider 22 . In addition, a plurality of groups of the slider fastening holes are formed in the mass body 21 , so that the fastening position of the slider 22 may be appropriately set.

For example, three or four sliders 22 may be mounted on the bottom surface of the mass body 21 . That is, the mass body 21 may be supported at three points or at four points by the slider 22 . In order to satisfy this condition, a plurality of slider fastening hole groups A to F may be formed to be spaced apart from each other by a predetermined interval in the mass body 21 .

If the mass body 21 is designed to have a three-point support structure, A, E, C groups or B, D, F groups are selected from among the plurality of fastening hole groups, and the slider 22 is included in these groups. can be mounted

Alternatively, if the mass body 21 is designed as a four-point support structure, A, D, F, and C groups are selected, and the slider 22 may be mounted to these groups.

As described above, since a plurality of coupling hole groups for coupling the slider 22 to the mass body 21 are formed, there is an advantage in that the degree of freedom for mounting the slider is increased.

Hereinafter, the case in which the four sliders 22 are mounted at four points of the mass body 21 will be described as an example. That is, it will be described as an example in which the four sliders 22 are arranged in groups A, D, F, and C. FIG.

7 is a perspective view of a support plate constituting a dynamic reducer according to an embodiment of the present invention.

Referring to FIG. 7 , the support plate 24 constituting the dynamic absorber 20 according to the embodiment of the present invention may be a rectangular metal plate. In addition, the support plate 24 may have a weight of approximately 1.5 kg.

In detail, the support plate 24 includes a cabinet seating part 242 that is seated on the upper end of the cabinet 11 and a raised part 247 that protrudes upward at a point spaced apart from the cabinet seating part 242 by a predetermined distance. ) and a mass body seating part 241 which is recessed to a predetermined depth downward from the inner side of the raised part 247 . The cabinet seating part 242 may be defined as a cabinet coupling part. In addition, the cabinet mounting part may include a left cabinet seating part (or a left cabinet coupling part) and a right cabinet seating part (or a right cabinet coupling part). Here, one of the left cabinet coupling unit and the right cabinet coupling unit may be referred to as a first cabinet coupling unit, and the other may be referred to as a second cabinet coupling unit.

In addition, the left and right widths of the mass body mounting part 241 are formed to be larger than the length of the mass body 21 , so that the mass body 21 is able to move in the left and right directions while seated on the mass body mounting part 241 . .

The mass body mounting part 241 may be recessed to a depth such that it does not come into contact with the bottom surface of the top plate 12 in a state in which the mass body 21 is seated on the mass body mounting part 241 .

In addition, one or a plurality of fastening holes 242a are formed in the cabinet seating part 242 , and a fastening member such as a screw penetrates the fastening hole 242a to be coupled to the upper end of the cabinet 11 . . 3, the upper surface of the cabinet 11, specifically the side cabinet 112, has a flat surface bent in the center direction of the cabinet 11, and the cabinet seating part ( 242) can be seated. In addition, the fastening member may sequentially pass through the cabinet seating part 242 and the flat piece.

In addition, the fastening hole 242a may be formed at the front end and the rear end of the cabinet seat 242, respectively, but is not limited thereto, and the front end, the center, and the rear of the cabinet seat 242 are not limited thereto. It is also possible to be formed at the end point.

Meanwhile, in order to reinforce the strength of the support plate 24 , a forming part 243 may be formed at the bottom of the mass body mounting part 241 . In detail, the forming portion 243 includes a first concave portion 243a recessed to a predetermined depth from the upper surface of the raised portion 247 and a plurality of first concave portions 243a alternately formed between the plurality of first concave portions 243a. It may include a convex part 243b and a second concave part 243c formed inside each of the plurality of convex parts 243b.

In addition, the first concave portion 243a and the convex portion 243b may extend from a left edge to a right edge of the mass body mounting portion 241 , and left and right sides of the second concave portion 243c . The ends may be spaced apart from the left and right edges of the mass body mounting part 241 by a predetermined distance.

As described above, the concave and convex portions are alternately formed and a plurality are formed, so that the strength of the support plate 24 is reinforced, and as a result, the natural frequency of the support plate 24 is increased. When the natural frequency increases, there is an advantage in that the possibility that the support plate 24 vibrates due to the vibration applied to the laundry treatment device 10 is reduced.

In addition, a slide fastening hole 244 is formed in the first concave portion 243a and the slider 25 is disposed in the first concave portion 243a to minimize the mounting height of the mass body 21 . can

Here, the length of the support plate 24 means the distance from the left cabinet seating part to the right cabinet seating part, and the width of the support plate 24 is from the front end to the rear end of the support plate 24 . is defined as the distance of

The support plate 24 serves not only to support the mass 21 but also to absorb the vibration transmitted to the cabinet 112 by holding the upper ends of the left and right side cabinets 112 . .

On the other hand, in the mass body seating part 241 , similarly to the mass body 21 , a plurality of slide fastening hole groups a to f are formed, and each slide fastening hole group includes a plurality of slide fastening holes 244 . includes In addition, a lower slider (refer to FIG. 10 ) is mounted in a slider fastening hole group of the support plate 24 that is directly below an upper slider (refer to FIG. 8 ) mounted on the mass body 21 .

Also, the mass body mounting part 241 is stepped or recessed from the upper surface of the support plate 24 to a depth equal to or greater than the thickness of the mass body 21 . When the top plate 12 is coupled to the upper surface of the cabinet 11 as the mass body mounting part 241 is stepped or recessed to a depth equal to or greater than the thickness of the mass body 21 , the mass body 21 is moved to the top plate (12) does not interfere. That is, the top plate 12 may be seated on the upper surface of the raised portion 247 or may be slightly spaced apart from the upper surface of the raised portion 247 .

If the mass body 21 interferes with the top plate 12 , a bottom surface of the top plate 12 or an upper surface of the mass body 21 is worn while the mass body 21 swings in the left and right directions. or it may be damaged. In addition, it prevents the mass body 21 from swinging in a phase opposite to the vibration phase of the cabinet 11 , so that the cabinet may not smoothly absorb vibrations.

Meanwhile, elastic damper fastening holes 245 for mounting the elastic damper 23 are formed at left and right edges of the mass body mounting part 241 . The elastic damper fastening hole 245 may be formed at left and right edges of the front end and left and right edges of the rear end of the support plate 24 .

The elastic dampers 23 may be disposed one by one at the center of the left and right edges of the mass body 21 , or two at the front and rear of each side end as shown. Alternatively, elastic dampers having a length corresponding to the front and rear widths of the mass body 21 may be disposed at the left and right edges of the mass body 21 .

Here, as the raised portion 247 is formed, the elastic damper 23 may be stably supported. In detail, when the mass body 21 collides with the elastic damper 23 , the elastic damper 23 is elastically deformed and pushed by the impact force of the mass body 21 . In this case, since the elastic damper 23 is supported by the raised portion 247 , separation of the elastic damper 23 from the support plate 24 may be prevented.

If the raised part 247 and the mass body seating part 241 are not formed and the support plate 24 is provided in the form of a flat iron plate, the elastic damper 23 is located on the left side of the support plate 24 . And it is coupled in a form that protrudes from the upper surface of the right edge. Then, the mass 21 will be placed between the left and right elastic dampers 23 . In this structure, when the mass body 21 moves in the horizontal direction, the elastic damper 23 colliding with the mass body 21 may be separated from the support plate 24 by an impact force.

In addition, a step portion 246 may be formed at a corner portion of the raised portion 247 . The bottom surface of the step portion 246 is formed to be higher than the cabinet seating portion 242 , so that the strength of the edge portion of the support plate 24 may be increased. Furthermore, when the top plate 12 is seated on the upper end of the cabinet 11 , the configuration including the rib protruding from the bottom surface of the top plate 12 corresponding to the upper side of the step portion 246 is described above. There is also an effect of preventing interference with the support plate 24 .

8 is a plan perspective view of an upper slider constituting a slider according to an embodiment of the present invention, and FIG. 9 is a bottom perspective view of the upper slider.

8 and 9 , the slider 22 according to an embodiment of the present invention includes an upper slider 25 mounted on a bottom surface of the mass body 21 and an upper surface of the support plate 24 . A lower slider 26 is included. It should be noted that any one of the upper slider 25 and the lower slider 26 may be defined as a first slider and the other may be defined as a second slider.

In detail, the upper slider 25 includes an upper slider body 251 having a substantially rectangular shape, a plurality of fastening protrusions 252 protruding from four corners of an upper surface of the upper slider body 251, and the upper slider body ( A plurality of slider rails 253 protruding from the bottom surface of the upper slider body 251 and extending in the longitudinal direction of the upper slider body 251 may be included.

In more detail, the plurality of fastening protrusions 252 may be inserted into the plurality of slider fastening holes 212 formed in the mass body 21 . The slider fastening holes 212 may be formed in the mass body 21 in a number corresponding to the number of the fastening protrusions 252 .

In addition, a plurality of slider fastening holes 212 corresponding to the number and positions of the fastening protrusions 252 may form one slider fastening hole group. And, as described above, a plurality of slider fastening hole groups may be formed in the mass body 21 so that the upper slider 25 can be coupled to the bottom surface of the mass body 21 at various positions.

The fastening protrusion 252 may protrude from four corners of the upper surface of the upper slider body 251 , but is not limited thereto. As another example, in a three-point support form, one fastening protrusion protrudes from the center of one edge of the upper surface of the upper slider body 251 , and one fastening protrusion protrudes from two corners of the opposite edge, respectively.

Alternatively, two or more fastening protrusions may be arranged in one row in the width direction from the center of the upper surface of the upper slider body 251 , or two or more fastening protrusions may be arranged in one row in the longitudinal direction.

In addition, two of the slider rails 253 may form a pair and be inserted into a rail receiving groove 262 (to be described later) formed in the lower slider 26 . When the slider rail 253 is accommodated in the rail accommodating groove 262 , the mass body 21 is oscillating on the support play 24 in a direction opposite to the left-right vibration of the cabinet 11 . Also, when the slider rail 253 is accommodated in the rail receiving groove 262 , it is possible to prevent the mass body 21 from swinging in the front-rear direction of the cabinet 11 .

Although it is shown that the two slider rails 253 are accommodated in the rail accommodating groove 262, the present invention is not limited thereto, and it should be noted that a structure in which three or more slider rails 253 are accommodated is also possible.

10 is a plan perspective view of a lower slider constituting a slider according to an embodiment of the present invention, and FIG. 11 is a bottom perspective view of the lower slider.

10 and 11 , the lower slider 26 constituting the slider 22 according to the embodiment of the present invention may have a rectangular shape having the same size as that of the upper slider 25 .

In detail, the lower slider 26 includes a lower slider body 261 having the same shape as that of the upper slider body 251 , and the upper surface of the lower slider body 261 in the longitudinal direction of the lower slider body 261 . It may include a rail accommodating groove 262 extending and formed, and a plurality of fastening protrusions 264 protruding from the bottom surface of the lower slider body 261 .

In more detail, the plurality of fastening protrusions 264 may be formed in the same shape and in the same number at the same formation position as the plurality of fastening protrusions 264 formed on the upper slider 25 . Accordingly, a redundant description of the plurality of fastening protrusions 264 formed on the lower slider 26 will be omitted. Of course, a plurality of slider fastening holes 244 corresponding to the plurality of fastening protrusions 264 are formed in the support plate 24 , and the slider fastening holes may be formed at a plurality of positions in groups.

In addition, a plurality of the rail receiving grooves 262 may be arranged side by side with a width smaller than the width of the slider body 261 . In addition, the plurality of rail receiving grooves 262 may be partitioned by a partition wall 263 .

In this embodiment, it is disclosed that the two rail accommodating grooves 262 are arranged side by side in the width direction of the slider body 261, but it is not excluded that three or more rail accommodating grooves are arranged side by side.

In addition, two or more slider rails 253 are accommodated in each rail receiving groove 262 , and at least two slider rails 253 are in contact with the front edge and rear edge of the rail receiving groove 262 . can make it happen

That is, the front side rail of the at least two slider rails 253 accommodated in the rail receiving groove 262 is in contact with the front edge of the rail receiving groove 262 , and the rear side rail is the rail receiving groove 262 . may be in contact with the rear edge of For example, when three slider rails are formed, two may be in contact with the front and rear surfaces of the rail accommodating groove 262 , and the other may be disposed in the center of the rail accommodating groove 262 .

In this way, by making the at least two slider rails 253 contact the front and rear edges of the rail receiving groove 262, when the mass body 21 moves in the left-right direction (longitudinal direction of the slider), friction is reduced. Thus, excessive vibration of the cabinet 11 may be absorbed. In addition, it is possible to obtain an effect of preventing the mass body 21 from swinging in the front-rear direction (the width direction of the slider).

In addition, the bottom surface of the slider rail 253 moves in the left and right direction while in contact with the bottom surface of the rail receiving groove 262 to generate frictional force, and excessive vibration of the cabinet 11 is prevented by the friction damping. can be absorbed.

In addition, the upper slider 25 and the lower slider 26 may be formed of an engineering plastic made of polyoxymethylene (POM) material. Also, since noise may be generated when plastics of the same material are in contact with each other, a lubricant such as grease may be applied to the rail receiving groove 262 .

Meanwhile, the length of the rail receiving groove 262 is formed to be longer than the length of the slider rail 253 , so that the upper slider 25 can reciprocate on the lower slider 26 in the left and right directions. This is because, if the upper slider 25 does not move left and right on the lower slider 26 , the mass 21 cannot vibrate in a phase opposite to the phase of the excitation force generated by the drum.

12 is a longitudinal cross-sectional view taken along line 12-12 of FIG. 4 .

12 , the slider 22 is disposed between the mass body 21 and the support plate 24 , and the upper slider 25 is fixedly mounted on the bottom surface of the mass body 21 , and the lower The slider 26 is fixedly mounted on the upper surface of the support plate 24 .

A plurality of slider rails 253 protruding and extending from a bottom surface of the upper slider 25 are accommodated in a rail receiving groove 262 formed on an upper surface of the lower slider 26 . In addition, two slider rails 253 are accommodated in each rail receiving groove 262 , and the two slider rails 253 are in contact with front and rear edges of the rail receiving groove 262 .

13 is a front perspective view of an elastic damper according to an embodiment of the present invention, and FIG. 14 is a bottom perspective view of the elastic damper.

13 and 14 , the elastic damper 23 constituting the dynamic damper 20 according to the embodiment of the present invention may be disposed on the left and right edges of the mass body 21 .

In detail, when the mass body 21 swings left and right, the left and right edges of the mass body 21 collide with the elastic damper 23 . At this time, the elastic damper 23 is elastically deformed to absorb the shock transmitted to the support plate 24 by the mass body 21 . In addition, the mass body 21 can reciprocate in a horizontal direction due to the elasticity of the elastic damper 23 .

And, when the drum constantly rotates at the maximum speed, the mass body 21 vibrates in the left and right directions due to the elasticity of the elastic damper 23 to partially absorb the normal vibration of the cabinet 11 .

In addition, two elastic dampers 23 may be respectively disposed on the left edge and right edge of the mass body 21 , but are not limited thereto, and three or more may be disposed. For example, the mass body 21 may be respectively disposed at the rear end, the center portion, and the front end of both side edges of the mass body 21 .

In addition, the elastic damper 23 may have a hexahedral shape including a front portion 231 , a rear portion 234 , a side portion 232 , an upper surface portion 233 , and a bottom surface portion 239 . In addition, an inclined portion 235 may be formed or formed to be rounded at a corner portion where the front portion 231 and the upper surface portion 233 meet.

In addition, a round portion 236 or an inclined portion may be formed at a corner portion where the bottom portion 239 and the rear portion 234 meet. As the inclined portion 235 is formed, when a horizontal force of the mass body 21 is applied to the front portion 231 , the shape of the elastic damper 23 is deformed and rises to form the top plate 12 and Interference can be prevented.

In addition, as the round part 236 is formed, when a horizontal force of the mass body 21 is applied to the front part 231 , the bottom edge of the rear end of the elastic damper 23 protrudes, so that the mass body seating part Interference with the edge of the side edge of the 241 can be prevented.

In addition, the elastic damper 23 includes an elastic groove 237 that is depressed upwardly from the bottom 239 , and a fastening arm protruding from the bottom 239 and fitted into the elastic damper fastening hole 245 . (238) may be further included.

In detail, the elastic groove 237 facilitates the shape deformation of the elastic damper 23 when the mass body 21 swings in the horizontal direction and presses the front part of the elastic damper 23 to absorb shock well. formed to be The elastic groove 27 may be defined as a shock absorbing groove, may be formed with a predetermined width in the left and right and front and rear directions, and may be recessed upward to a predetermined depth.

The elastic groove 27 is formed at a position adjacent to the front part 231 rather than the rear part 234 , so that the mass body 21 can easily absorb the shock. In addition to the structure in which the elastic groove 27 is opened from the bottom surface of the elastic damper 23 and depressed upward, a structure in which the elastic groove 27 is opened from the upper surface of the elastic damper 23 and is depressed downward is also possible. For example, it is revealed that it is also possible to be opened in the inclined portion 235 and to be depressed to a predetermined depth downward.

In addition, the fastening arm 238 may include an extended end 238a extending a predetermined length from the bottom portion 239 and a locking protrusion 238b extending from a side edge of the end of the extended end 238a. can

That is, the fastening arm 238 may be formed in an inverted T-shape, but is not limited thereto. A cross section of the extension end 238a has a size corresponding to the shape of the elastic damper fastening hole 245, and the fastening arm 238 is connected to the elastic damper fastening hole 245 by the locking protrusion 238b. is prevented from falling out.

In order to couple the fastening arm 238 to the elastic damper fastening hole 245 , first tilt the elastic damper 23 so that one locking protrusion 238b is inserted through the elastic damper fastening hole 245 . do. Next, the elastic damper 23 may be tilted to the opposite side so that the opposite locking protrusion 238b is inserted through the elastic damper fastening hole 245 .

In addition, in order to prevent the elastic damper 23 from swinging in the vertical direction while it is coupled to the support plate 24 , the length of the extension end 238a corresponds to the thickness of the support plate 24 . length can be made. In other words, the distance from the bottom portion 239 to the upper end of the locking protrusion 238b may be set equal to the thickness of the support plate 24 .

In addition, the fastening arm 238 may be formed at a point closer to the rear part 234 than the front part 231 of the elastic damper 23 .

15 is a longitudinal cross-sectional view taken along line 15-15 of FIG. 7 .

Referring to FIG. 15 , a separate depression, that is, the second concave portion 243c, is also formed inside the convex portion 243b, thereby increasing the natural frequency of the support plate 24 .

In detail, the bottom of the second recessed part 243c may form the same plane as the bottom of the first recessed part 243a, but is not limited thereto. That is, the bottom of the first recessed part 243a may be lower than the bottom of the second recessed part 243c.

FIG. 16 is a longitudinal cross-sectional view taken along lines 16-16 of FIG. 7 .

Referring to FIG. 16 , the bottom of the first recessed part 243a may be lower than the cabinet seating part 242 .

In detail, the first recessed part 243a may be recessed from the upper surface of the raised part 247 , and the first recessed part 243a may be recessed to a position lower than that of the cabinet seating part 242 . Here, the depth of the depression of the first depression 243a is limited by a structure such as the tub 16 accommodated in the cabinet 11 . That is, it is necessary to prevent the bottom of the first recessed part 243a from interfering with the upper surface of the tub 16 .

If there is no interference of a structure such as the tub 16, the raised portion 247 may not be necessary. That is, it may be possible for the mass body mounting part 241 to be depressed to a depth corresponding to the thickness of the mass body 21 in the cabinet mounting part 242 .

Meanwhile, as the depth of the depression of the first depression 243a is limited, the upper surface of the convex portion 243b may be formed at a higher position than the cabinet seating portion 242 . The position of the upper surface of the convex part 243b may be determined by the thickness of the mass body 21 . That is, the upper surface of the convex portion 243b may be located at a point spaced downward from the upper surface of the raised portion 247 by a distance corresponding to the thickness of the mass body 21 . Accordingly, the upper surface of the convex part 243b may be located above the cabinet seating part 242 or below the cabinet seating part 241 depending on the thickness of the mass body 21 . .

In summary, the distance h1 from the convex part 243b to the first recessed part 243a is the distance h3 between the convex part 243b and the cabinet seating part 241 and the first recessed part 243a. It is equal to the sum of the distance h2 between the 243a and the cabinet seating part 242 .

Hereinafter, a method for improving the excessive vibration of the laundry treatment apparatus by appropriately setting a vibration absorption area or absorption width capable of effectively absorbing the excessive vibration generated in the cabinet by the dynamic damper 20 will be described.

Equation 1 below is a dimensionless response expression showing the behavior of the dynamic reducer to vibrations generated when a drum having an eccentric load rotates.

,

,

,

,

,

,

,

,

Y: dimensionless oscillatory displacement (or amplitude) of the mass,

r : operation speed ratio (or operation frequency ratio)

ω: rotational speed (or rotational frequency) of the drum

ω _a : natural frequency (or natural frequency) of the mass

ω _p : natural frequency (or natural frequency) of the laundry treatment device

β : frequency ratio (or frequency ratio)

μ: mass ratio

ma _a : mass of mass

m _p : mass of the laundry treatment unit

ζ : damping ratio

c _a : mass attenuation

The dimensionless response equation of the dynamic reducer uses a mass ratio, a frequency ratio, and a damping ratio as variables. The mass ratio is strictly defined as the mass ratio of the mass body 21 to the mass of the laundry treatment device 10, but In terms of mass ratio, it is irrelevant. This is because elements other than the mass body 21 among the components of the dynamic absorber 20 are fixed to the laundry treatment device 10, it can be viewed as a part of the mass of the laundry treatment device 10, and the laundry treatment This is because it has little influence on determining the overall mass of the device 10 . This is because the upper slider mounted on the bottom surface of the mass body 21 also has a mass that is negligible compared to the mass of the mass body 21 . Therefore, it should be noted that the mass ratio may be interpreted as the mass ratio of the dynamic reducer 20 .

In addition, it should be noted that the frequency ratio and damping ratio may also be defined or interpreted as the frequency ratio of the dynamic absorber 20 and the damping ratio of the dynamic reducer 20, similarly to the mass ratio.

On the other hand, the shape of the response curve drawn by the response equation is determined by the mass ratio, the frequency ratio, and the damping ratio, and the vibration absorption capacity of the dynamic absorber 20 is determined by these variables. That is, if the rotational speed ratio of the drum is increased while the mass ratio, the frequency ratio, and the damping ratio, which are the variables of the response equation, are appropriately selected, the dimensionless amplitude of the dynamic reducer is calculated. In addition, the calculated dimensionless value may be regarded as the vibration displacement of the cabinet 11 .

Here, the mass ratio of the dynamic absorber 20 is a design variable that determines the absorption region, and the frequency ratio (or frequency ratio) and the damping ratio are design parameters that determine the vibration displacement of the secondary transient vibration after absorption. In detail, when the mass body 21 of the dynamic absorber 20 operates at the resonance point, excessive vibration is absorbed, and two secondary transient vibrations that are significantly smaller than the vibration displacement when the excessive vibration occurs are generated.

In addition, the distance between the two secondary transient vibrations is defined as an absorption region or an absorption width, and the size of the absorption region may vary depending on the mass ratio. And, the vibration displacement, that is, the peak point of the two secondary transient vibrations may be changed by adjusting the frequency ratio and the damping ratio.

For reference, on the response graph, the two second-order transient oscillations are represented by two peak points where the dimensionless amplitude value suddenly increases and then decreases. The interval between the two peak points is interpreted as an exhaust region, and the interval between the two peak points is changed by adjusting the mass ratio.

Meanwhile, the resonance frequency at which the excessive vibration occurs may vary depending on the size, mass, product deviation, and eccentricity of the laundry (load) put into the drum. In this situation, in order for the dynamic damper 20 to effectively absorb excessive vibration of the laundry treatment apparatus 10 to improve vibration, the vibration absorption region should be formed to be equal to or larger than the resonance frequency region.

In order to identify the resonance region in which excessive vibration occurs, the resonant frequency region in which the excessive vibration occurs by varying the amount of laundry input, the type of laundry, the weight of the laundry, and the size of the washing machine, was confirmed through an experiment. As a result, the rotational speed of the drum It was confirmed that transient vibration mainly occurred within the range of 700rpm to 1050rpm. It can be seen that the resonance point of the excessive vibration has a deviation of 350 rpm depending on the eccentricity of the load.

This means that the region in which the dynamic absorber 20 can absorb the excessive vibration, that is, the absorption region (or the absorption width), must be able to cover all of the transient vibration generation section.

Here, in the absorption region of the dynamic reducer 20, the rotation frequency at the point in time when the mass body 21 starts to move in a direction opposite to the excitation force generated by the accelerated rotation of the drum and the rotation speed of the drum increase Accordingly, it may be defined as a width between rotation frequencies when the mass body 21 stops due to a decrease in vibration generated by the excitation force.

In addition, the factor determining the size of the excessive vibration absorption region of the dynamic damper 20 is the mass ratio. That is, the larger the mass ratio, the wider the excessive vibration damping area, and the smaller the mass ratio, the narrower the damping area. In other words, as the mass of the mass 21 increases, it means that excessive vibration can be absorbed in a wide section.

According to the above experiment, it can be seen that the dynamic absorber 20 needs to have a vibration absorption area (or absorption width) of at least 300 rpm and at most 400 rpm. In order to satisfy these conditions, as a result of performing an experiment for setting the mass ratio, it was confirmed that the exhaust area was about 300 rpm when the mass ratio was 4%. In addition, the minimum mass of the mass body 21 at this time is preferably set to about 4±0.5 kg in consideration of product deviation and eccentric load of the laundry treatment apparatus 10 .

When the absorption area is narrowed to less than 300 rpm, the difference between the vibration displacement of the transient vibration that occurs when the dynamic absorber is not installed and the vibration displacement of the secondary transient vibration that occurs after the excessive vibration is absorbed after the dynamic absorber is installed is large. Therefore, the actual exhaustion effect is not large.

On the other hand, in order to widen the exhaust area, the mass ratio may be increased, but the internal space of the cabinet 11 in which the dynamic absorber 20 is mounted is limited. In detail, since the dynamic reducer 20 is mounted on the upper surface of the cabinet 11 and the dynamic reducer 20 is covered by the top plate 12, the planar area of the dynamic reducer 20 is There is a limitation that the thickness and thickness cannot be increased indefinitely. In addition, since the total mass of the laundry treatment apparatus 10 also increases when the mass of the dynamic absorber 20 increases, the mass of the dynamic absorber 20 cannot be increased indefinitely.

Theoretically, if the mass of the dynamic absorber 20, specifically, the mass of the mass 21 and the total mass of the laundry treatment apparatus 10 to which the dynamic absorber 20 is mounted, is the same, the excessive vibration is most It can be completely absorbed.

However, if the mass of the mass body 21 is excessively large, the load of the laundry treatment apparatus 10 is too large, so movement and installation are difficult, and the mass body 21 may sag due to its own weight. Above all, there is a limit to increasing the load (or mass) of the mass body 21 due to the limitation of the installation space inside the cabinet 11 .

Accordingly, the exhaust region is limited to a maximum of 400 rpm, the mass ratio of the dynamic absorber 20 at this time is 10%, and the maximum mass of the mass body 21 may be set to about 10±0.5 kg.

More preferably, when the exhaust region is 350 rpm, the mass ratio of the dynamic absorber 20 is 7%.

17 is a graph showing the vibration displacement of a laundry treatment apparatus equipped with a dynamic absorber.

The horizontal axis of the graph represents the rotational speed (rpm) of the drum, and the vertical axis represents the vibration displacement of the cabinet. The rotation speed may be regarded as the same concept as the rotation frequency.

Referring to FIG. 17 , graph A is a graph of the vibration displacement of a cabinet measured in a laundry treatment apparatus not equipped with a dynamic absorber 20, and graph B is a laundry treatment apparatus equipped with a dynamic reducer 20 having a mass ratio of 7%. It is a graph of the vibration displacement of the cabinet measured in

First, let's look at the case in which the dynamic absorber 20 is not mounted.

The drum into which the laundry for rinsing or dehydration is put begins to rotate, and as the rotation speed increases, a horizontal excitation force is generated by the rotation of the eccentric laundry loaded into the drum. Also, the horizontal vibration displacement of the cabinet is increased by the excitation force.

And, when the rotational speed of the drum reaches the resonance frequency, the cabinet vibrates excessively due to resonance. On the graph, it is confirmed that the resonance point at which the excessive vibration occurs is approximately 900 rpm.

And, when the rotation speed of the drum exceeds the resonance frequency, the vibration is gradually reduced. And, in a section in which the drum is maintained at the maximum speed, the cabinet undergoes normal vibration in which the vibration displacement value hardly changes.

On the other hand, looking at the case in which the dynamic absorber 20 is mounted, as the rotation speed of the drum increases, the vibration displacement of the cabinet 11 also increases. And, in the low-speed section in which the dynamic reducer 20 does not start, the behavior of the vibration displacement graph is not significantly different from that in the case where the dynamic reducer 20 is not mounted.

However, when the rotational frequency (or rotational speed) of the drum falls within the frequency range at which the dynamic reducer 20 starts, the dynamic reducer 20 starts to move. Then, the increased vibration displacement of the cabinet decreases sharply, and as the rotation speed of the drum increases, the vibration displacement of the cabinet, which has decreased sharply, gradually increases again. That is, it can be seen that the excessive vibration generated when the dynamic absorber is not installed is absorbed by the dynamic absorber.

Then, the vibration displacement of the cabinet increases until the vibration of the mass body 21 stops, and when the rotational speed of the drum deviates from the absorption region of the dynamic absorber 20 , the mass body 21 stops.

In detail, when the drum exceeds the resonant frequency, the vibration due to the excitation force is weakened and the vibration displacement of the cabinet is also reduced. Accordingly, when the rotational speed of the drum deviates from the excessive vibration absorption region of the dynamic damper 20, the vibration displacement of the cabinet decreases and then is maintained as the displacement in the normal vibration.

Here, looking at graph B, it can be seen that as the transient vibration is absorbed by the dynamic absorber 20, two inflection points a and b having a vibration displacement smaller than the vibration displacement in the transient vibration are formed. Vibrations at the two inflection points may be defined as secondary transient vibrations. In addition, it can be said that the two inflection points a and b correspond to two peak points appearing in the response curve.

In detail, the two secondary transient oscillations appear at the initial point and the end point of exhaustion, respectively. The forward secondary transient vibration is vibration that occurs because the mass body 21 absorbs the vibration that has been increasing as it starts to move. And, the secondary transient vibration at the back is vibration that occurs because the mass body 21 stops moving and the cabinet behaves under the same conditions as when the dynamic reducer 20 is not mounted.

In addition, when the absorption region is widened through the adjustment of the mass ratio, the vibration displacement in the secondary transient vibration can be further reduced, and the time when the front secondary transient vibration occurs can be advanced to the low speed section. Then, there is an advantage in that the stability of the washing machine is improved compared to the case where excessive vibration occurs in the high-speed section.

In addition, by adjusting the frequency ratio and damping ratio, it is possible to control the vibration displacement in the rear secondary transient vibration to be significantly lower than the vibration displacement in the front secondary transient vibration.

Here, the two secondary transient vibrations are generated because the vibration absorption amount is the largest at the resonance point of the drum. That is, since the mass body 21 is designed to absorb the excessive vibration as much as possible by causing it to vibrate the most in the direction opposite to the direction of vibration generated by the excitation force at the resonance point where the excessive vibration occurs, both ends of the vibration absorption region It can be said that it is natural for the secondary transient vibration to occur in

On the other hand, it can be seen that, as the width of the absorption region increases, the vibration displacement of the secondary transient vibration is significantly reduced, and the vibration absorption effect is large. Conversely, it can be seen that as the width of the absorption region is smaller, the vibration absorption effect is not large because the difference between the vibration displacement of the transient vibration before the dynamic damper is mounted and the vibration displacement of the secondary transient vibration is not large.

Claims (20)

cabinet;
a drum accommodated inside the cabinet;
a tub for accommodating the drum; and
and a dynamic absorber provided to absorb the vibration of the cabinet;
The dynamic absorber,
a support plate coupled to the cabinet;
a mass resting on the support plate; and
a slider interposed between the mass body and the support plate to enable the mass body to reciprocate with damping due to frictional force on the plate;
The slider is
a lower slider mounted on the support plate;
and an upper slider mounted on a lower surface of the mass body and slidably placed on an upper surface of the lower slider. The method of claim 1,
The dynamic absorber,
The laundry treatment apparatus further comprising one or more elastic dampers mounted on the support plate and disposed on one side edge of the mass body and the other side edge of the mass body opposite to the one side edge. 3. The method of claim 2,
The support plate is
a raised portion raised from the outer edge and formed on the edge of the mass body to form a mass body accommodating groove in the support plate;
a first cabinet coupling part extending from one side edge of the raised part and coupled to the cabinet;
and a second cabinet coupling part extending from the edge of the other side of the raised part and coupled to the cabinet;
One side edge of the raised portion is laundry treatment apparatus, characterized in that opposite to the other side edge of the raised portion. 4. The method of claim 3,
A length in a first direction of the mass body receiving groove is formed to be greater than a length in the first direction of the mass body,
The first direction is a movement direction of the mass,
and the elastic damper is disposed in a space formed between an edge of the mass body and an edge of the mass body accommodating groove. 4. The method of claim 3,
The support plate is placed on top of the cabinet,
The mass moves horizontally on the support plate,
The first and second cabinet coupling units are respectively coupled to left and right upper ends of the cabinet. 5. The method of claim 4,
A plurality of forming parts recessed for strength reinforcement are formed on the bottom of the mass body receiving groove,
The plurality of forming units extend in the first direction and are spaced apart from each other in a second direction intersecting the first direction. 7. The method of claim 6,
Further comprising a recess formed between the forming parts adjacent to each other,
The plurality of forming parts are formed to have a length corresponding to the width of the mass body receiving groove in the first direction,
The concave portion is a laundry treatment apparatus, characterized in that the length is formed to be shorter than the width of the mass body receiving groove in the first direction. The method of claim 1,
The slider is a laundry treatment device, characterized in that molded from a plastic material having a predetermined frictional force. 9. The method of claim 8,
The upper slider is
upper slider body,
a plurality of first fastening protrusions protruding from the upper surface of the upper slider body;
a plurality of slider rails protruding and extending from a bottom surface of the upper slider body;
The lower slider is
a lower slider body,
a plurality of second fastening protrusions protruding from the lower surface of the lower slider body;
and a rail receiving groove recessed in an upper surface of the lower slider body to accommodate the plurality of slider rails. 10. The method of claim 9,
A plurality of upper slider fastening holes into which the plurality of first fastening protrusions are inserted are formed in the mass;
The laundry treatment apparatus according to claim 1, wherein a plurality of lower slider fastening holes into which the plurality of second fastening protrusions are inserted are formed in the support plate. 10. The method of claim 9,
The rail accommodating groove is formed separately into two rail accommodating grooves by a partition wall,
At least two slider rails are accommodated in each of the rail receiving grooves. 3. The method of claim 2,
A fastening arm is formed protruding from the bottom surface of the elastic damper,
Laundry treatment apparatus, characterized in that the support plate is formed with a fastening hole into which the fastening arm is fitted. 13. The method of claim 12,
An elastic groove is formed inside the elastic damper,
The elastic groove is depressed downward from the upper surface of the elastic damper, or is depressed upwardly from the bottom surface of the elastic damper,
The elastic groove is a laundry treatment apparatus, characterized in that formed between the surface in contact with the mass and the fastening arm. The method of claim 1,
The mass body is made of a single metal plate, or a laundry treatment apparatus, characterized in that formed by laminating a plurality of thin metal plates. 4. The method of claim 3,
The raised portion is a laundry treatment apparatus, characterized in that it is surrounded along the edge of the mass. cabinet;
a drum accommodated inside the cabinet;
a tub for accommodating the drum; and
a dynamic absorber provided to absorb vibrations of the cabinet; including,
The dynamic absorber,
a support plate mounted on the cabinet;
a mass resting on the support plate; and
a damping member interposed between the mass body and the support plate, the mass body having damping due to frictional force on the plate;
Laundry treatment apparatus, characterized in that the vibration absorption width of the dynamic absorber is in the range of 300rpm ~ 400rpm around the area in which the rotational speed of the drum is 900rpm. 17. The method of claim 16,
The laundry treatment apparatus, characterized in that the mass ratio of the dynamic absorber is within the range of 4% to 10%. 17. The method of claim 16,
The absorption width of the dynamic absorber is a laundry treatment apparatus, characterized in that 350rpm. 19. The method of claim 18,
The laundry treatment apparatus, characterized in that the mass ratio of the dynamic absorber is 7%. 17. The method of claim 16,
The mass of the mass body is a laundry treatment apparatus, characterized in that within the range of 4 ± 0.5 kg ~ 10 ± 0.5 kg.

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