KR20050021860A - Washing Machine for Reducing Vibration - Google Patents

Abstract

PURPOSE: A vibration-reduced washing machine is provided to lower the degree of vibration by choosing proper materials for a leg combining member or a damper buffering member with minimizing the modification of a cabinet quality and thickness or a depth of a bead resulting in the increase of production cost and to design an effective vibration-reduced washing machine in a whole range of the rotational frequency by considering other characteristics, such as a hardness and slip-tolerance, to choose materials. CONSTITUTION: A vibration-reduced washing machine is composed of a cabinet profiling the washing machine; a tub installed in the cabinet to store washing water; a drum rotatively installed in the tub; and a damper(15) installed between a base(36) of the cabinet and the tub to reduce a transmission of vibration generated at the drum. The damper is combined with the cabinet by a first buffering member(110) contacted with the damper and by a second buffering member(120) contacted with the first buffering member. Either the first buffering member or the second buffering member is a copolymer of a hard block and a soft block. The second buffering member is contacted with a third buffering member having the same material quality as the first buffering member. The hard block is a material satisfying necessary mechanical characteristics, and the soft block is a material satisfying vibration reducing characteristics.

Description

Washing Machine for Reducing Vibration

The present invention relates to a washing machine, and more particularly, to a damper capable of effectively reducing the vibration generated during operation of the washing machine and a vibration reducing washing machine having the damper.

The washing machine is a device that exfoliates contaminants by applying energy such as impact to laundry, and may be divided into a pulsator washing machine, a drum washing machine, and an agitator washing machine according to a method of applying energy to laundry. In the drum washing machine, the laundry is dropped by the rotation of the drum, thereby impacting the laundry, and washing is performed by adding a detergent. In the pulsator washing machine and the agitator washing machine, the laundry is impacted by the rotation of a pulsator or agitator mainly coupled to a washing shaft installed vertically in an inner tank, and washing is performed by adding a detergent action.

That is, the washing machine is a method of washing by giving a shock to the laundry mainly by a mechanical method, and for this purpose, the washing tank or the drum on which the laundry is placed is rotated, and thus vibration is usually generated. Therefore, the washing machine is provided with various vibration reduction means capable of reducing vibration.

Prior to describing a vibration reduction method generally used in the related art, a general drum washing machine as an example of a washing machine will be described with reference to FIGS. 1 and 2 as follows.

The cabinet 3 constituting the body of the washing machine is composed of a front part 34, a side part 32, an upper cover 38, and a lower base 36. The front part 34 of the cabinet 3 is installed so that the door 4 can be opened and closed, and the base 36 is provided with the leg 5 which supports the washing machine on the floor on which the washing machine is placed.

A tub 7 for storing the wash water is installed in the cabinet 3, and a drum 9 in which the laundry is placed is rotatably installed in the tub 7. Of course, the tub 7 is coupled to the motor 11 for generating a driving force for rotating the tub (7).

On the other hand, as described above, when the washing machine is operated, the drum 9 rotates at a high speed, thereby causing vibration. In particular, since the drum 9 rotates at a high speed in the dehydration stroke, the generation of vibration is severe. Therefore, various devices for reducing vibration or attenuating vibration generated in the design of the washing machine are installed in the washing machine.

For example, in order to prevent and reduce vibration generated in the drum 9 from being transmitted to the cabinet 3 or the like, a spring 13 is installed between the tub 7 and the upper cover 38 and the tub ( A damper 15 is provided between 7) and base 36. In addition, the material and thickness of the cabinet 3, in particular, the side portion 32 or the base 36 may be adjusted, or the beads 32a may be formed in the side portion 32 of the cabinet 3. In addition, as shown in detail in Figure 3, the leg 5 is provided with a leg coupling member 17 formed of a material capable of reducing vibration.

However, the conventional vibration reduction method and a washing machine using the same have the following problems.

First, since the correlation between the various vibration reduction devices described above is not clear, there is a limit to efficiently reduce vibration from a comprehensive point of view.

Second, there was a problem that effective vibration reduction was difficult over the entire range of rotational speed of the drum or motor of the washing machine. For example, when the damping force of the damper is largely designed to reduce the transient vibration caused by the nonuniform distribution of the laundry when entering the dehydration stroke, a problem arises that the vibration becomes rather large at the rated dehydration rotation speed. On the contrary, if the damping force of the damper is designed small, the vibration at the rated spin speed decreases while the transient vibration occurs. In addition, even in the case of the leg coupling member, the rotational speed of the washing machine effective for reducing vibration is approximately determined according to the material, and there is a problem that effective vibration reduction over the entire range of the washing machine rotational speed is difficult.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a damper and a washing machine using the same which can efficiently reduce vibration.

Another object of the present invention is to provide a damper of a washing machine effective in reducing vibration over the whole range of the rotation speed of the washing machine and a washing machine using the same.

In order to achieve the above object, the present invention provides a cabinet forming the outer appearance of the washing machine, a tub installed inside the cabinet to store the wash water, a drum rotatably installed in the tub, and in the drum A washing machine including a damper provided between a base of the cabinet and the tub to reduce transmission of vibration generated, wherein the damper comprises: a first buffer member in contact with the damper; and a second buffer member in contact with the first buffer member. It is coupled to the cabinet via a buffer member, it provides a washing machine, characterized in that one of the first buffer member and the second buffer member is a block copolymer of a hard block and a soft block.

Therefore, according to the present invention described above, it is possible to efficiently reduce the vibration generated in the washing machine.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

First, referring to Figures 4 and 5, the principle of the vibration reduction washing machine according to the present invention will be described.

The present inventors studied to find the most effective method for vibration reduction among various methods of vibration reduction. As a result, it has been found that optimizing the leg coupling member among the various factors such as damper, cabinet material, thickness and shape, and material of the leg coupling member is most effective in reducing vibration. 4 and 5 show experimental results demonstrating that proper design of the leg coupling member is effective for vibration reduction.

4 and 5 are graphs showing the principle and effect of the vibration reduction washing machine according to the present invention. That is, the vibration in the dehydration process was measured for various types of washing machines (hereinafter referred to as "samples") in which various factors were generally known to be effective in reducing vibration. In the vibration measurement test, an eccentricity of 400 g was given, and the vibration amount was measured at the upper edge portion A and the center portion B of the right side surface of the cabinet using a vibration amount measuring instrument (EQP / 2). 4 is an experimental result of the right side part of a cabinet, and FIG. 5 is an experimental result of the left side part of a cabinet. 4 and 5, A (maximum) means the maximum vibration measured at the upper edge portion, A (normal) means the vibration of the steady state measured at the upper edge portion. Similarly, B (maximum) means the maximum vibration measured at the center part, and B (normal) means the steady state vibration measured at the center part.

It will be described in detail as follows. Sample 1 gives a bead formed on the side of the cabinet 0.15mm more than the general depth and the material of the leg coupling member is a drum washing machine using a conventional butyl rubber. Sample 1a is the same drum washing machine as Sample 1, but is a washing machine in which only the material of the leg coupling member is changed. Sample 2 is a drum washing machine using a conventional butyl rubber without changing the depth of the beads and the material of the leg coupling member. Sample 2a is the same drum washing machine as Sample 2, but changes only the material of the leg coupling member.

Here, the leg coupling member used in Samples 1a and 2a is a material that shows the best results among a number of materials studied and tested by the present inventors. (The details of the leg coupling member will be described later.)

4 and 5 are as follows.

The results of experiments on the sample 1 and the sample 2 which are the same as that of the leg coupling member and differ only in the depth of the bead, it can be seen that increasing the bead depth has some effect on vibration reduction. However, it can be seen that the correlation between bead depth and vibration reduction is not clear.

However, the bead depth is the same, and the results of experiments on the sample 1 and the sample 1a or the sample 2 and the sample 2a with different leg coupling members, it can be seen that the appropriate leg coupling member is very effective in reducing vibration.

In addition, the experimental results for the samples 1a and 2a, it can be seen that optimizing the material of the leg coupling member than the depth of the beads is effective to reduce the vibration.

Therefore, in order to effectively reduce vibration, it is desirable to design the leg coupling member most appropriately.

As described above, in order to effectively reduce the vibration, it is preferable to design the leg coupling member most appropriately. Thus, the inventors further studied the material of the leg coupling member, especially the leg coupling member, and the results are as follows.

The leg coupling member is required to first have excellent vibration reduction characteristics. However, in order to be used as an actual leg coupling member, not only vibration reduction characteristics but also various other conditions must be satisfied. For example, conditions such as mechanical properties such as hardness, slip resistance to prevent the washing machine from slipping at the washing machine installation location, and moldability indicating ease of manufacture should also be satisfied. This is because, for example, even if the vibration reduction characteristic is satisfied, if the proper hardness is not obtained, a resonance phenomenon may occur in a certain region of the RPM of use of the washing machine, and there is a concern that the washing of the washing machine may occur. In addition, when the frictional force with the floor is small, there is a fear that the washing machine is slipped on the floor.

As a result, the leg coupling member must satisfy the above-described conditions in addition to the vibration reduction characteristics, but it is difficult to select the optimal leg coupling member that satisfies all of these conditions in the prior art. Therefore, to date, empirically, metal, plastic, butyl rubber (Isobutylene-isoprene Rubber) and the like have been used as leg coupling members, but each material has advantages and disadvantages. The metal or plastic has a relatively high hardness, so that the resonance region is outside the RPM range of the washing machine, but there is a concern that the washing machine may occur in almost all regions regardless of the rotation range. In addition, the frictional force with the floor which is the installation place of the washing machine is small, there is a fear that the sliding of the washing machine occurs. In the case of butyl rubber, the resonant zone is a low speed RPM (RPM) region of the washing machine. Therefore, the washing machine must be controlled to pass through the resonant zone quickly. It may occur.

In order to solve this problem, the present inventors have studied the material of the leg coupling member, and it is very effective to use a block copolymer of a hard block and a soft block as the material of the leg coupling member. I found out. That is, as shown in Figure 6, it was found that it is preferable to manufacture a leg bonding member using a copolymer in which the hard block HS and the soft block SS are meshed. Because, when the block copolymer of hard block and soft block is used as the material of the leg coupling member, the hard block may select a material that satisfies mechanical properties such as the required hardness, and the soft block may select a material that satisfies vibration reduction characteristics. Because there is. Therefore, it is possible to design a leg coupling member that satisfies other conditions while also satisfying vibration reduction characteristics relatively easily.

In view of the vibration reduction effect, the block copolymer according to the present invention, particularly the soft block, it is preferable to use a material exhibiting a glass transition phenomenon, it is more preferable that the glass transition temperature is near the use temperature of the washing machine. Because at higher temperatures than the glass transition temperature, the thermal motion of each part of the chain-shaped polymer having a net-like structure becomes violent, indicating a rubbery state, but below the glass transition point, the thermal motion decreases in its own volume. This is because it is suppressed and hardened (glassy state), and the vibration reduction effect is lowered.

In the case of non-nodular polymer materials such as rubber, glass transition is exhibited, so it is preferable to select a rubber material as the leg bonding member, and butyl rubber is currently used in glass transition. However, as mentioned above, the leg coupling member is required to satisfy not only vibration reduction characteristics but also other characteristics, but butyl rubber is a copolymer made by copolymerizing a small amount of isoprene in isobutylene and the hard block according to the present invention. Unlike the block copolymer of the soft block, it is difficult to satisfy other than vibration reduction characteristics. In terms of vibration reduction properties, butyl rubber has a glass transition temperature of -40 ° C to -60 ° C, which is much lower than the temperature at which the washing machine is used. As shown in FIG. 7, in the case of butyl rubber, the damping performance is generally uniform in the operating temperature range of the washing machine, but the damping performance is lower than that of the leg coupling member of the block copolymer according to the present invention.

As described above, the leg coupling member according to the present invention uses a block copolymer of a hard block and a soft block as a material of the leg coupling member, the hard block is selected in terms of mechanical properties, the soft block is selected in terms of vibration damping. do.

Therefore, the soft block is preferably selected from a material whose glass transition temperature is close to the operating temperature of the washing machine, for example, -30 ° C to 30 ° C. Of course, the hard block is preferably selected from the material required in terms of mechanical properties such as hardness. For example, in the case of a washing machine installed on a slippery floor, such as cement or tile, it is good to make the hardness of the leg coupling member high. It is usually desirable to have Shore A hardness of about 80. On the other hand, in the case of a wooden floor, Shore A hardness is preferably about 30 so that the hardness is low.

As a result of experiments with various materials, it is preferable that the hard block is polystyrene, and the soft block is polyisoprene, particularly vinyl-polyisoprne.

Although the block copolymer may be used alone when fabricating the leg-bonding member, the block copolymer may be an olefin-based thermoplastic resin, an ethylene-alpha olefin copolymer, an ethylene-vinylacetate copolymer, an ethylene-ethyl acrylate copolymer, styrene-butadiene It is of course also possible to blend and use at least one of a styrene copolymer and a styrene-isoprene-styrene copolymer. In addition, it is also possible to appropriately add additives such as a crosslinking agent, a filler, a softener and the like based on the above-described block copolymer, which is obvious in the art, and thus detailed description thereof will be omitted.

When the leg coupling member is made using the block copolymer of the hard block and the soft block as described above, it is possible to form a leg coupling member that satisfies vibration reduction characteristics and other necessary characteristics.

In order to confirm this, experiments were conducted using materials that generally satisfy the above-mentioned conditions among commercially available materials. The material used in the experiment was Kuraray's Hybrid. Hibra is a block copolymer of polystyrene and polyisoprene and has a glass transition temperature of approximately -19 ° C to 8 ° C near room temperature. As a result, as shown in Figure 7, the leg coupling member using a hi-bra was confirmed that the damping force is very excellent in the vicinity of room temperature. In FIGS. 4 and 5, the material used as the leg coupling member in Samples 1a and 2a is also a leg coupling member using a hibra. Of course, the material suitable for the leg coupling member is not limited to the hibra, any one can be used as long as the above conditions are satisfied.

On the other hand, as described above, the leg coupling member is preferably excellent in formability, workability, etc. in view of the manufacturing cost of the washing machine as well as the vibration reduction characteristics. In addition, the washing machine preferably has slip resistance and the like so as not to slip on the floor. Hibra has better slip resistance than butyl rubber, and especially has good frictional force in water environments compared to other rubbers. In addition, the hibra can be made of a thermoplastic resin that can be injected and extruded, or a thermosetting resin that can be pressed. However, in order to use the thermosetting resin, a separate crosslinking agent is required.

On the other hand, as shown in Figure 8, the leg is coupled to the leg coupling member in a predetermined manner. Referring to the example of the preferred coupling of the leg and the leg coupling member as follows.

First, the legs are explained as follows. Generally, the leg 5 includes a circular body portion 52 and a head portion 54 formed at the lower end of the body portion 52. And, the outer peripheral surface of the body portion 52 is preferably formed with a screw thread for easy height adjustment. The head portion 54 serves to facilitate the height adjustment of the leg by easily rotating the threaded body portion 52.

On the other hand, the leg coupling member 17 is coupled to the lower end of the leg (5). The leg coupling member 17 may be directly coupled to the head 54 of the leg 5, but an extension 56 is further formed on the lower portion of the head 54 in consideration of securing the coupling area and ease of coupling. It is preferable that the leg coupling member 17 is coupled to the extension 56.

Joining of the leg 5 and the leg coupling member 17 may be performed by insert molding, bonding or other methods. For example, the leg 5 and the leg coupling member 17 can be bonded using an adhesive. In addition, the leg 5 and the leg coupling member 17 may be coupled to each other using insert molding, or may be detachably coupled to each other using an elastic hook.

Meanwhile, in the above-described embodiment, the drum washing machine is illustrated and described, but the present invention is not limited thereto. That is, the present invention is also applicable to pulsator washing machines and agitator washing machines. In addition to the washing machine, it is also applicable to a dryer.

On the other hand, according to the research of the present inventors, the principle of the present invention can be applied not only to legs, but also to parts used for vibration reduction in other washing machines. In particular, it is preferable to apply the principle of the present invention to a damper provided between the base of the cabinet and the tub so that vibration generated in the drum is not transmitted to the cabinet.

9 to 12, the application of the principle of the present invention to a damper of a drum washing machine will be described in detail as follows.

One side of the damper 15 is coupled to the base 36 of the cabinet via the buffer member. At this time, the entire buffer member may be formed of one material, that is, the block copolymer according to the present invention. However, as a result of the present inventor's study, the present invention provides two or more buffer members, for example, one of the block copolymers according to the present invention. The other is more preferably formed of another material such as butyl rubber. This is because the above-described block copolymers of the hard block and the soft block may cause plastic deformation after a certain period of time, thereby lowering the vibration damping effect.

It will be described in detail as follows. For convenience of explanation, the upward hatching portion (eg, reference numeral 120 in FIG. 9) in the drawing means that the material is a block copolymer, and the left upward hatching portion (for example, reference numeral 110 in FIG. 9) is made of butyl material. It means a rubber.

As shown in FIG. 9, the damper 15 may be formed through a first buffer member 110 in contact with the damper 15 and a second buffer member 120 in contact with the first buffer member 110. Coupled to the base 36 of the cabinet, one of the first buffer member 110 and the second buffer member 120 is a block copolymer of a hard block and a soft block.

In detail, a hollow coupling portion 15a is formed at one side of the damper 15 (part connected to the base 36 of the cabinet). In addition, a cylindrical first buffer member 110 is installed at the coupling portion 15a, and a cylindrical second buffer member 120 is installed at the hollow portion of the first buffer member 110. And, the base 36 is coupled to the bracket 16, one side of which is opened in the damper direction.

That is, the coupling portion 15a of the damper 15, the first buffer member 110, and the second buffer member 120 are positioned in the opening of the bracket 16, and in this state, the bolt 16a is attached to the bracket 16. ) And the second buffering member 120 are installed through the damper 15 to be installed between the tub and the cabinet.

Meanwhile, as shown in FIG. 9, the material of the first buffer member 110 may be made of butyl rubber and the material of the second buffer member 120 may be a block copolymer. However, as shown in FIG. 10, the material of the first buffer member 110 is preferably a block copolymer and the material of the second buffer member 120 is butyl rubber. This is because it is advantageous to use a block copolymer made of the material of the first buffer member 110 in contact with the damper 15 in terms of reducing vibration.

11 and 12, it is also possible to provide a third buffer member 130 having the same material as the material of the first buffer member 110 inside the second buffer member 120. .

On the other hand, the combination of the first buffer member 110, the second buffer member 120 and the third buffer member 130 may use a bonding or double injection, and can be used in various ways, detailed description thereof will be omitted. do.

The present invention is not limited to the above-described embodiments, and those skilled in the art can make modifications without departing from the concept of the present invention, and such modifications are within the scope of the present invention.

The effects of the damper and the washing machine using the same according to the present invention described above are as follows.

First, according to the present invention, there is an advantage that the vibration can be efficiently reduced by appropriately selecting the leg coupling member and the damper buffer member. That is, the vibration of the washing machine can be efficiently reduced while minimizing changes in the material, thickness, and bead depth of the cabinet, which cause a design change, an increase in production cost, and the like. That is, by appropriately selecting the damper buffer member and the leg coupling member, which are relatively easy to change the design and confirm the effect, there is an advantage that the vibration can be reduced very efficiently.

Second, according to the present invention, it is possible to select not only the vibration reduction characteristics but also other necessary characteristics such as hardness, slip resistance, etc., at the same time selecting a leg coupling member and a damper buffer member. Therefore, there is an advantage that a washing machine having an effective vibration reduction over the whole range of the rotation speed of the washing machine can be designed.

1 is a perspective view showing a conventional drum washing machine according to the related art

2 is a longitudinal cross-sectional view of FIG.

3 is a side view showing the leg of FIG. 1 in detail;

4 and 5 is a graph showing the principle and effect of the vibration reduction washing machine according to the present invention

Figure 6 schematically shows the structure of the leg coupling member that can be used in the vibration reduction washing machine according to the present invention

Figure 7 is a graph showing a comparison of the damping force of the leg coupling member and the butyl rubber leg coupling member according to the present invention

8 is an exploded perspective view showing the leg and the leg coupling member according to the present invention

9 to 12 are cross-sectional views showing in detail the coupling portion of the damper as another embodiment of the vibration reducing washing machine according to the present invention.

<Explanation of symbols for the main parts of the drawings>

3: cabinet 15: damper

32: side part 34: front part

36: base 32a: bead

5: leg 17: leg coupling member

15a: coupling portion 16: bracket

110: first buffer member 120: second buffer member

130: third buffer member 16a: bolt

Claims (10)

A cabinet forming an outer shape of the washing machine, a tub installed inside the cabinet to store wash water, a drum rotatably installed inside the tub, and a reduction of transmission of vibration generated from the drum. In the washing machine comprising a damper provided between the base and the tub, The damper is coupled to the cabinet via a first buffer member in contact with the damper and a second buffer member in contact with the first buffer member, wherein one of the first buffer member and the second buffer member is soft with the hard block. Washing machine, characterized in that the block copolymer of the block. The washing machine according to claim 1, wherein a third buffer member having the same material as the first buffer member is in contact with the second buffer member. The washing machine according to claim 1 or 2, wherein the hard block is a material satisfying the required mechanical properties, and the soft block is a material satisfying vibration reduction characteristics. The washing machine according to claim 3, wherein the soft block has a glass transition temperature of room temperature. The washing machine according to claim 4, wherein the glass transition temperature is -30 ° C to 30 ° C. The washing machine according to claim 3, wherein the hard block is polystyrene and the soft block is polyisoprene. The washing machine according to claim 6, wherein the soft block is vinyl polyisoprene. The method of claim 7, wherein the block copolymer is an olefinic thermoplastic resin, ethylene-alpha olefin copolymer, ethylene-vinylacetate copolymer, ethylene-ethyl acrylate copolymer, styrene-butadiene-styrene copolymer, styrene-isoprene- Washing machine, characterized in that formed by blending with at least one of the styrene copolymer. The washing machine according to claim 3, wherein the first buffer member, the second buffer member, and the third buffer member are coupled by an adhesive. The washing machine according to claim 3, wherein the first buffer member, the second buffer member and the third buffer member are coupled by insert molding.