JP2011250852A - Washing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a washing machine capable of suppressing vibration generated at housing caused by vibration of an outer tank.SOLUTION: In a washing machine, a vibration absorber 22 for fixing an outer tank to housing 1a so as not to vibrate is connected via a cushioning mechanism 22c to a housing 1a and an outer tank. The cushioning mechanism 22c includes a cushioning unit 203 having a vibration absorbing rubber 200 with a hollow part 201 in which a magnetic fluid is enclosed, an electromagnet 202 capable of putting the magnetic fluid in a magnetic field generated by the electromagnet 202, and the viscosity of magnetic fluid can be varied by varying its viscosity property with the magnetic field generated by the electromagnet 202. Thus, the viscosity property of the cushioning unit 203 is varied depending on the rotational speed of a rotative drum that rotates in the outer tank and a rate of transmission of vibration of the outer tank to the housing 1a is made small.

Description

  The present invention relates to a drum type washing machine.

2. Description of the Related Art A drum type washing machine including a rotating drum for storing laundry in an outer tub elastically supported by a housing is widely known.
The rotating drum of such a washing machine is connected to a drive motor by a shaft and is rotationally driven by the drive motor. And since a vibration generate | occur | produces in an outer tank by rotation of a rotating drum, the outer tank is supported by the housing | casing via the vibration isolator which absorbs the vibration of an outer tank.

When the rotating drum is rotated at a high rotational speed, such as dehydration, vibration is generated in the casing due to resonance in the process of increasing the rotational speed of the rotating drum, and abnormal vibration and noise are generated in the washing machine. Therefore, a structure that suppresses vibration generated in the housing is preferable.
For example, some vibration isolator that elastically supports the outer tub absorbs the vibration in the vertical direction of the outer tub and prevents it from being transmitted to the housing. There are cases where vibrations in the front-rear direction cannot be absorbed.

For example, Patent Document 1 discloses a drum-type washing machine including a damper whose damping force changes depending on the magnitude of vibration of the outer tub. According to the technique disclosed in Patent Literature 1, when a larger vibration is generated in the outer tub than in a steady state, the damping force is increased and the vibration can be absorbed.
Further, for example, Patent Document 2 discloses a dewatering washing machine including a control type fluid damper in which an amount of attenuation is variable according to rotation speed, vibration, and noise. According to the technique disclosed in Patent Document 2, it is possible to increase the damping force near the resonance rotation and reduce the vibration at the time of resonance.
For example, Patent Document 3 discloses a technique for attaching a vibration-proof damper to a fixed side via a liquid-filled buffer rubber. According to the technique disclosed in Patent Document 3, the vibration generated in the drum can be reduced by increasing the damping force by enclosing the liquid in the buffer rubber.
For example, Patent Document 4 discloses a drum-type washing machine that fixes a vibration-proof damper that suppresses vibration of a water tank to a base plate of a main body case and a water tank support base via a cushion material. According to the drum type washing machine disclosed in Patent Document 4, the vibration transmitted from the water tank to the main body case is reduced by making the hardness of the cushion material provided on the base plate side smaller than the hardness of the cushion material provided on the water tank support base side. Can be reduced.

JP 2008-200179 A JP 2001-170390 A JP 2009-101167 A JP 2001-212395 A

However, in the technique disclosed in Patent Document 1, the damping force of the damper changes depending on the magnitude (displacement) of the vibration of the outer tub. There is a problem that an impact sometimes occurs.
Further, the technique disclosed in Patent Document 2 has a problem that the structure of the control type fluid damper becomes complicated because an electromagnet or a magnetic fluid is incorporated in a cylinder in which a piston is housed.
Moreover, in the technique disclosed in Patent Document 3, even when the rotational speed of the drum is high, the damping force of the buffer rubber is high, and vibration generated in the drum when the rotational speed is high is generated in the washing machine body. There is a problem of being easily transmitted.
Further, in the technique disclosed in Patent Document 4, when the hardness of the cushion material is set to a hardness that can reduce vibration at the time of resonance, there is a problem that vibration is easily transmitted to the main body case when the drum rotates normally.

  Then, this invention makes it a subject to provide the washing machine which can suppress the vibration which generate | occur | produces in a housing | casing by the vibration of an outer tub.

  In order to solve the above-described problems, the present invention provides a vibration isolator that elastically supports an outer tub in a casing, and a washing machine that can change at least one of rigidity and elasticity of a buffer portion that connects the outer tub and the casing.

  ADVANTAGE OF THE INVENTION According to this invention, the washing machine which can suppress the vibration generate | occur | produced in a housing | casing by the vibration of an outer tub can be provided.

It is sectional drawing which shows the internal structure of a drum type washing machine. It is sectional drawing which shows the structure of the housing | casing side buffer mechanism which concerns on 1st Embodiment. It is a figure which shows the functional block of a washing machine. It is a graph which shows the transmission rate when the plane vibration which generate | occur | produces in an outer tank transmits to a housing | casing. (A), (b) is a figure which shows the modification of the shape of the hollow part formed in the shock absorbing rubber which concerns on 1st Embodiment. It is sectional drawing which shows the structure of the housing | casing side buffer mechanism which concerns on 2nd Embodiment. It is a graph which shows the relationship between the rotational speed of a rotating drum, and the magnitude | size of a left-right vibration. It is a graph which shows the relationship between the rotational speed of a rotating drum, and the magnitude | size of a longitudinal vibration. It is sectional drawing which shows the modification of the housing | casing side buffer mechanism which concerns on 2nd Embodiment. It is sectional drawing which shows the other modification of the housing | casing side buffer mechanism which concerns on 2nd Embodiment. (A)-(c) is a schematic diagram which shows the state of the vibration of the rotary body which has an upper mass point and a lower mass point. (A), (b) is a schematic diagram which shows the state of the vibration of the modeled washing machine. It is a figure which shows the structure of the housing | casing side buffer mechanism and outer tank side buffer mechanism which concern on 3rd Embodiment.

<< First Embodiment >>
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings as appropriate.
As shown in FIG. 1, the washing machine 1 according to the first embodiment continuously performs a washing process (washing process and rinsing process) for washing laundry, a dehydration process, and a drying process (if necessary). This is a so-called drum-type washing / drying machine that is selectively) washed and dried, and is a front surface of a housing 1a supported by a base 15 having legs 16 that contact a floor such as a laundry pan (not shown). In addition, a door 7 for taking in and out the laundry is provided.
In addition, the washing machine 1 sets the left-right direction as the front (front) side of the door 7 and the front direction from the back (rear) with respect to the front. Also, the vertical direction is set with the side on which the legs 16 are provided as the bottom.

An operation / display panel 8 provided with, for example, an operation button for a user to operate the washing machine 1 and a display unit for the user to check the state of the washing machine 1 is provided on the front side of the housing 1a. Is equipped.
Further, for example, on the upper side on the back side, a water intake 9 that takes in water from a water supply source such as a water supply, a water supply valve 9 a that opens and closes the water intake 9, and a water supply pipe that guides water taken from the water intake 9 to the outer tub 2. 9b is provided.

Inside the housing 1a, a plurality of vibration isolators 22 that can extend and contract in the vertical direction (one anti-vibration device 22 is shown in FIG. 1) is supported below, and elastically from above the housing 1a. An outer tub 2 is provided which is elastically supported by suspension springs 18 and 19 serving as a support.
With this configuration, the outer tub 2 is elastically supported by the housing 1a.
The outer tub 2 is configured in a cylindrical shape with an opening on the front side, and the rotating drum 3 is accommodated as an inner tub into which laundry is put. The rotating drum 3 is connected to a driving means (driving motor 4) attached to the bottom of the outer tub 2 via a shaft 4 a, and rotates in the outer tub 2 by the rotational driving of the driving motor 4. And the washing machine 1 performs a washing | cleaning process, a rinse process, a spin-drying | dehydration process, etc. by rotation of the rotating drum 3. FIG.

  The outer tub 2 is configured to accumulate water during a process using water such as a washing process (washing process, rinsing process), and a drain hose 14 is connected via a drain valve 21. When the drain valve 21 is opened, the water accumulated in the outer tub 2 flows through the drain hose 14 and is drained.

  Reference numeral 6 is a control device for controlling the washing machine 1, reference numeral 50 is a rotational speed detecting device for measuring the rotational speed of the drive motor 4, reference numeral 51 is a vibration sensor for measuring vibration generated in the outer tub 2, and reference numeral 52 is It is a water level sensor that measures the water level of water accumulated in the outer tub 2. The rotational speed detection device 50 is, for example, a rotational speed meter that measures the rotational speed of the shaft 4a, and the vibration sensor 51 is configured by, for example, an acceleration sensor that measures acceleration generated in the outer tub 2.

  The vibration isolator 22 includes a damper 22a and a coil spring 22b, and attenuates the vibration of the outer tub 2 by expansion and contraction of the damper 22a. In the vibration isolator 22, for example, the damper 22a side is connected to the outer tank 2 via the outer tank side buffer mechanism 22c2, and the coil spring 22b side is connected to the bottom of the casing 1a via the casing side buffer mechanism 22c1.

  The vibration isolator 22 configured as described above can absorb the vibration in the vertical direction generated in the outer tub 2 by the expansion and contraction of the damper 22 but cannot absorb the vibration in the horizontal direction and the front-rear direction. Therefore, the vibration isolator 22 and the casing 1a and the outer tub 2 are connected to each other by the casing-side buffer mechanism 22c1 and the outer tub-side buffer mechanism 22c2, respectively, and vibrations in the left-right direction and the front-rear direction generated in the outer tub 2 are The mechanism 22c1 and the outer tank side buffer mechanism 22c2 are configured to absorb. Hereinafter, the housing side buffering mechanism 22c1 and the outer tank side buffering mechanism 22c2 may be collectively referred to as a buffering mechanism 22c.

As shown in FIG. 2, the damper 22a includes a cylinder (not shown) and a rod 22e, and a damping force is obtained by friction between the cylinder and the rod 22e. The coil spring 22b of the vibration isolator 22 is disposed around the rod 22e of the damper 22a, and is configured to expand and contract between the locking portion 22g fixed to the rod 22e and the cylinder in accordance with the vertical movement of the cylinder. Is done.
And the housing side buffering mechanism 22c1 that connects the vibration isolator 22 and the housing 1a is provided below the locking portion 22g (on the side of the housing 1a), for example, a rod 22e (of the rod 22e extending downward from the locking portion 22g). A ring-shaped buffer member (buffer rubber 200) attached so as to surround the extension portion) is configured to sandwich the housing 1a.

  The buffer member is not limited to the buffer rubber 200 and may be a material having a suitable viscosity. Furthermore, as will be described later, since the buffer member is provided with the hollow portion 201, the buffer member is preferably a material excellent in workability.

The shock absorbing rubber 200 is configured to be divided in the vertical direction, for example, and the upper shock absorbing rubber 200a is incorporated on the upper side of the housing 1a (on the vibration isolator 22 side), and the lower shock absorbing rubber 200b is incorporated on the lower side of the housing 1a. It may be configured.
Then, the washer 204 and the upper cushioning rubber 200a are fitted into the screw portion 22f formed at the tip of the rod 22e in this order from above, and the screw portion 22f is passed through the through hole opened at the lower portion of the housing 1a. The lower shock absorbing rubber 200b and the washer 204 are fitted to the threaded portion 22f penetrating the screw. Then, the nut 205 is fastened to the screw portion 22f.
By assembling the housing side buffer mechanism 22c1 in this manner, the vibration isolator 22 and the housing 1a can be connected via the housing side buffer mechanism 22c1.

In addition, hollow portions 201 and 201 are formed concentrically with the ring-shaped outer shape inside the upper cushion rubber 200a and the lower cushion rubber 200b according to the first embodiment. Magnetic fluid is enclosed. Further, around the upper buffer rubber 200a and the lower buffer rubber 200b, electromagnets 202 and 202 are provided along the outer periphery, and configured to generate a magnetic field and place a magnetic fluid in the magnetic field.
And the buffer part 203 of the buffer mechanism 22c is formed including the upper buffer rubber 200a, the lower buffer rubber 200b, the two electromagnets 202, and the magnetic fluid.

When the magnetic fluid is placed in a magnetic field, the viscosity increases. Therefore, when the electromagnets 202 and 202 generate a magnetic field, the viscosity of the magnetic fluid increases, and the viscosity of the buffer 203 having the buffer rubber 200 in which the magnetic fluid is sealed is increased. Increase.
In addition, since the viscosity of the magnetic fluid changes depending on the amount of magnetic field (the amount of magnetic field), the magnitude of the viscosity of the buffer 203 can be controlled by controlling the amount of magnetic field generated by the electromagnets 202 and 202.
The viscosity of the buffer 203 is a characteristic value obtained by dividing the magnitude of resistance depending on the deformation speed of the buffer 203 by the deformation speed.

The outer tank side buffer mechanism 22c2 (see FIG. 1) that connects the vibration isolator 22 and the outer tank 2 (see FIG. 1) has the same configuration as the housing side buffer mechanism 22c1 that connects the vibration isolator 22 and the casing 1a. . And what is necessary is just to comprise so that the outer tank 2 may be clamped with the upper side buffer rubber 200a and the lower side buffer rubber 200b.
Then, the buffer mechanism 22c (the housing side buffer mechanism 22c1 and the outer tank side buffer mechanism 22c2) is configured as shown in FIG. 2, whereby the vibration isolator 22 is connected to the housing 1a and the outer tank 2 via the buffer mechanism 22c. Will be connected.

The washing machine 1 (see FIG. 1) configured as described above is controlled by the control device 6 (see FIG. 1).
The control device 6 controls the washing machine 1 by controlling the rotational speed of the drive motor 4 (see FIG. 1), opening and closing the drain valve 21 (see FIG. 1), opening and closing the water supply valve 9a (see FIG. 1), and the like.

As shown in FIG. 3, the control device 6 includes a microcomputer 6a, and the microcomputer 6a executes a program stored in a memory (not shown) to control the washing machine 1.
The control device 6 includes a rotation speed of the shaft 4a (see FIG. 1) measured by the rotation speed detection device 50, a vibration of the outer tank 2 (see FIG. 1) measured by the vibration sensor 51, and an outer tank measured by the water level sensor 52. A water level of 2 is entered. The control device 6 is configured to be able to control the operation / display panel 8, the water supply valve 9 a, the drain valve 21, the motor drive circuit 4 b that generates a drive signal for the drive motor 4, and the electromagnet 202.

  The control device 6 configured as described above executes a washing process in accordance with a user operation. For example, when executing the washing process or the rinsing process, the control device 6 opens the water supply valve 9a to inject water into the outer tub 2 (see FIG. 1), and the water level of the outer tub 2 measured by the water level sensor 52 is predetermined. When the reference value is reached, the water supply valve 9a is closed and the drive motor 4 is rotationally driven to rotate the rotary drum 3 (see FIG. 1). The control device 6 acquires the rotation speed of the shaft 4a (see FIG. 1) measured by the rotation speed detection device 50 as the rotation speed of the rotation drum 3, and maintains the rotation speed of the rotation drum 3 at a predetermined value.

Further, when executing the dehydration process, the control device 6 opens the drain valve 21 to drain the water in the outer tub 2 and then rotates the drive motor 4 at high speed to rotate the drum 3 (see FIG. 1). Is rotated at high speed to dehydrate laundry not shown.
At this time, the control device 6 acquires the vibration measured by the vibration sensor 51 as the vibration of the outer tub 2 (see FIG. 1), and stops the dehydration process when the vibration of the outer tub 2 exceeds the reference value.

  Moreover, when performing the drying process, the control device 6 blows air heated by a heater (not shown) into the outer tub 2 to dry the laundry.

  Furthermore, the control device 6 controls the operation / display panel 8 as necessary, and displays necessary information on a display unit (not shown). As described above, the control device 6 controls the washing machine 1 to execute the washing process, the dehydrating process, and the drying process.

  Among these, in the dehydration process, the rotating drum 3 (see FIG. 1) is rotated at a high speed, but in the process of increasing the rotating speed of the rotating drum 3, the outer tub 2 (see FIG. 1) is connected to the rotating drum 3 and the drive motor 4. (See FIG. 1) and the like, vertical vibration that vibrates in the vertical direction, horizontal vibration that vibrates in the horizontal direction, longitudinal vibration that vibrates in the front-rear direction, and plow vibration that vibrates in a plane rotation state are generated. These vertical vibrations, left-right vibrations, longitudinal vibrations, and pruning vibrations are generated when the rotational speed of the rotary drum 3 reaches a specific rotational speed at which resonance occurs in each vibration.

  Among these, the vertical vibration can be absorbed by the vibration isolator 22 (see FIG. 1) having the damper 22a (see FIG. 1) that moves up and down according to the vertical movement of the outer tub 2 (see FIG. 1). Therefore, it can suppress that the vertical vibration which generate | occur | produces in the outer tank 2 is transmitted to the housing | casing 1a, and a vibration generate | occur | produces in the housing | casing 1a.

  However, the left-right vibration, the front-rear vibration, and the pruning vibration (hereinafter, the left-right vibration, the front-rear vibration, and the pruning vibration are collectively referred to as plane vibration) are mainly vibrations that tilt the vibration isolator 22 (see FIG. 1). However, since it cannot be converted into the vertical motion of the damper 22a (see FIG. 1), it cannot be absorbed by the vibration isolator 22, and is transmitted to the housing 1a (see FIG. 1). And vibration generate | occur | produces in the housing | casing 1a and abnormal vibration and noise generate | occur | produce in the washing machine 1 (refer FIG. 1).

  Therefore, the washing machine 1 according to the first embodiment is configured to absorb the plane vibration with the viscosity of the buffer portion 203 (see FIG. 2) of the buffer mechanism 22c (see FIG. 1).

As shown in FIG. 4, the transmission rate when the plane vibration generated in the outer tub 2 (see FIG. 1) is transmitted to the housing 1a (see FIG. 1) is a frequency (twice the root of the resonance frequency of the plane vibration ( (Hereinafter referred to as transition frequency) becomes “1”, is larger than “1” in the region below the transition frequency, and smaller than “1” in the region above the transition frequency.
Since the frequency of the plane vibration generated in the outer tub 2 changes according to the rotational speed ω of the rotating drum 3 (see FIG. 1), the horizontal axis in FIG. The ratio of the rotational speed ω to the speed ωn (hereinafter referred to as a specific rotational speed ωn) is shown.

  Cases 1 to 5 indicate differences due to the magnitude of the damping force of the buffer mechanism 22c (see FIG. 1). Case 5 has the largest damping force, and indicates that the damping force decreases toward Case 1 as the damping force decreases. Yes.

For example, in the case 5 in which the damping force of the buffer mechanism 22c (see FIG. 1) is the largest, when the rotational speed ω of the rotating drum 3 (see FIG. 1) is lower than twice the route of the specific rotational speed ωn, However, when the rotational speed ω of the rotary drum 3 is higher than twice the route of the specific rotational speed ωn, the transmission rate is the highest among Cases 1 to 5.
On the other hand, in the case 1 where the damping force of the buffer mechanism 22c is the smallest, when the rotational speed ω of the rotating drum 3 is lower than twice the root of the specific rotational speed ωn, the transmission rate is the highest among the cases 1 to 5, but the rotating drum When the rotational speed ω of 3 is higher than twice the route of the specific rotational speed ωn, the transmission rate is the smallest among Cases 1 to 5.

In other words, when the damping force of the buffer mechanism 22c (see FIG. 1) is large, the outer tub 2 (see FIG. 1) when the rotational speed ω of the rotating drum 3 (see FIG. 1) is lower than twice the root of the specific rotational speed ωn. ) From the outer tub 2 to the housing 1a when the rotational speed ω of the rotating drum 3 is higher than twice the root of the specific rotational speed ωn. The effect of absorbing the plane vibration transmitted to is reduced.
On the other hand, when the damping force of the buffer mechanism 22c is small, the effect of absorbing the plane vibration transmitted from the outer tub 2 to the housing 1a is low when the rotational speed ω of the rotary drum 3 is lower than twice the route of the specific rotational speed ωn. Thus, when the rotational speed ω of the rotating drum 3 is higher than twice the route of the specific rotational speed ωn, the effect of absorbing the plane vibration transmitted from the outer tub 2 to the housing 1a is enhanced.

  Therefore, in the washing machine 1 (see FIG. 1) according to the first embodiment, when the rotational speed ω of the rotary drum 3 (see FIG. 1) is lower than twice the root of the specific rotational speed ωn, the buffer mechanism 22c (FIG. 1). When the rotational speed ω of the rotating drum 3 is higher than twice the root of the specific rotational speed ωn, the damping force of the buffer mechanism 22c is decreased so that the rotational speed ω of the rotating drum 3 does not depend on the rotational speed of the rotating drum 3. The effect of absorbing the plane vibration transmitted from the outer tub 2 to the housing 1a is increased.

The damping force of the buffer mechanism 22c (see FIG. 1) changes according to the viscosity of the buffer portion 203 (see FIG. 2). When the viscosity of the buffer portion 203 is high, the damping force increases, and when the viscosity is low, the damping force decreases. The power is reduced.
Therefore, in the first embodiment, when the rotational speed ω of the rotating drum 3 (see FIG. 1) is lower than twice the route of the specific rotational speed ωn, the control device 6 (see FIG. 1) is configured to have electromagnets 202 and 202 (see FIG. 2). Power) to generate a magnetic field, increase the viscosity of the magnetic fluid sealed in the hollow portion 201 (see FIG. 2) of the buffer rubber 200 to increase the viscosity of the buffer portion 203, and the housing side buffer The damping force of the mechanism 22c1 and the outer tank side buffer mechanism 22c2 is increased.
On the other hand, when the rotational speed ω of the rotating drum 3 is higher than twice the route of the specific rotational speed ωn, the control device 6 stops supplying power to the electromagnets 202 and 202 to extinguish the magnetic field, and the hollow portion of the buffer rubber 200 The viscosity of the magnetic fluid enclosed in 201 is reduced to reduce the viscosity of the buffer portion 203, and the damping force of the housing side buffer mechanism 22c1 and the outer tank side buffer mechanism 22c2 is decreased.

  With this configuration, when the rotational speed ω of the rotating drum 3 is lower than twice the root of the specific rotational speed ωn, the plane vibration is transmitted to the housing 1a at a transmission rate indicated by Case 5 in the graph shown in FIG. Thus, the transmission rate at which plane vibration is transmitted to the housing 1a can be kept low. Further, when the rotational speed ω of the rotary drum 3 is higher than twice the route of the specific rotational speed ωn, the plane vibration is transmitted to the housing 1a at a transmission rate indicated by Case 1 in the graph shown in FIG. The transmission rate at which the plane vibration is transmitted to the housing 1a can be kept low. Therefore, regardless of the rotational speed ω of the rotating drum 3, the transmission rate at which the planar vibration is transmitted to the housing 1a can be kept low, and the vibration generated in the housing 1a can be suitably suppressed.

  It should be noted that the shape and material of the buffer rubber 200 (see FIG. 2), the amount and type of the magnetic fluid to be sealed, the amount of the magnetic field generated by the electromagnet 202, and other buffer mechanisms 22c (the housing side buffer mechanism 22c1, the outer tank side buffer mechanism) Since the viscosity of the buffer 203 (see FIG. 2) changes according to the design value of 22c2), the housing side buffer mechanism 22c1 and the outer tank side buffer are set so that the viscosity can effectively suppress the transmission of plane vibration. These design values of the mechanism 22c2 may be determined as appropriate.

Moreover, as shown to (a) of FIG. 5, (b), the structure by which the hollow part 201 formed in the shock absorbing rubber 200 is divided | segmented into a some block may be sufficient. For example, as shown in FIG. 5 (a), a plurality of partition walls 201a (in FIG. 5 (a)) are provided with a hollow portion 201 formed radially concentrically with the outer shape of the ring-shaped shock absorbing rubber 200. It is also possible to divide the four partition walls 201a into a plurality of blocks and form a hollow portion 201 that is divided into a plurality of blocks.
As described above, when plane vibration occurs in the outer tub 2 (see FIG. 1) or the like, the vibration isolator 22 (see FIG. 1) tilts and loads on one of the hollow portions 201 divided into a plurality of blocks. It takes. Accordingly, the magnetic fluid enclosed in one of the divided blocks receives a load when the vibration isolator 22 tilts, and the viscosity of the buffer 203 (see FIG. 2) can be increased. Further, the buffer rubber 200 can be reinforced by the partition wall 201a.

  Further, as shown in FIG. 5B, a through hole 201b may be formed in the partition wall 201a. When the vibration isolator 22 (see FIG. 1) tilts and a load is applied to one block, the magnetic fluid of the block to which the load is applied passes through the through hole 201b and moves to the adjacent block. And the viscosity of the buffer part 203 (refer FIG. 2) can be increased by the flow resistance which generate | occur | produces when a magnetic fluid passes the through-hole 201b.

  In addition, when the vibration isolator 22 (see FIG. 1) is tilted, the deformation amount on the outer peripheral side of the ring-shaped shock absorbing rubber 200 (see FIG. 1) is larger than the deformation amount on the inner peripheral side. 2) is formed on the outer peripheral side of the buffer rubber 200, a large change in viscosity can be obtained with a small magnetic fluid.

  Furthermore, it is good also as a structure which replaces with a magnetic fluid and encloses ER fluid (electrorheological fluid) in the hollow part 201 (refer FIG. 2). In this case, if the electrode is arranged in the hollow portion 201 so that a voltage can be applied to the ER fluid, the viscosity of the buffer portion 203 (see FIG. 2) can be controlled by controlling the voltage applied to the ER fluid.

In the description of the first embodiment, the left-right vibration, the front-rear vibration, and the pruning vibration are plane vibrations without distinction, but the left-right vibration, the front-rear vibration, and the resonation vibration generate resonance. The specific rotational speed exists as different characteristic values, and the transmission rate of all the plane vibrations is equivalent to the magnitude of the damping force of the buffer mechanism 22c (see FIG. 1) (the characteristic shown in FIG. 4). Have
Accordingly, the planar vibration in the first embodiment may be configured to generate, for example, the largest vibration in the case 1a (see FIG. 1) among the left-right vibration, the front-rear vibration, and the pruning vibration.

  Further, when a plurality of vibration isolators 22 (see FIG. 1) are provided, the vibration isolator 22 in which the viscosity of the shock absorber 203 (see FIG. 2) changes corresponding to the left-right vibration, and the shock absorber corresponding to the longitudinal vibration. The anti-vibration device 22 in which the viscosity of the part 203 changes and the anti-vibration device 22 in which the viscosity of the buffer part 203 changes corresponding to the plowing vibration may be provided. In this case, the control device 6 (see FIG. 1) controls each vibration isolator 22 based on the resonance frequency and the specific rotation speed at which resonance occurs due to the left-right vibration, the front-rear vibration, and the pruning vibration.

  Alternatively, the amount of the magnetic field generated by the electromagnet 202 (see FIG. 2) may be controlled to change the viscosity of the buffer unit 203 in three stages corresponding to, for example, left-right vibration, longitudinal vibration, and plowing vibration.

  In addition, the washing machine 1 (refer FIG. 1) which concerns on 1st Embodiment is the buffer part 203 (FIG. 2) of both the housing | casing side buffer mechanism 22c1 (refer FIG. 1) and the outer tank side buffer mechanism 22c2 (refer FIG. 1). However, for example, the viscosity of only the buffer portion 203 of the housing side buffer mechanism 22c1 may be changed, or only the buffer portion 203 of the outer tank side buffer mechanism 22c2 may be configured. You may comprise so that the viscosity of can be changed.

<< Second Embodiment >>
The washing machine 1 (see FIG. 1) according to the first embodiment is provided with a shock absorber 22c1 (see FIG. 1) of a housing side buffer mechanism 22c1 (see FIG. 1) that connects the vibration isolator 22 (see FIG. 1) and the housing 1a (see FIG. 1). Absorbs plane vibration by changing the viscosity of the buffer 203 of the outer tank side buffer mechanism 22c2 (see FIG. 1) connecting the part 203 (see FIG. 2) and the vibration isolator 22 and the outer tank 2 (see FIG. 1). In the second embodiment of the present invention, the rigidity of the buffer portion of the buffer mechanism 22c is changed to suppress the vibration generated in the casing 1a. .
Therefore, as shown in FIG. 6, a buffer mechanism 22 c including a variable elastic body 206 is used instead of the magnetic fluid sealed in the buffer rubber 200.

The variable elastic body 206 is a material having a property of decreasing rigidity when placed in a magnetic field. For example, as shown in FIG. 6, the variable elastic body 206 has a ring-shaped variable elastic body 206 formed by a lower cushion rubber 200 b and a lower washer 204. The electromagnet 202 is disposed around the variable elastic body 206.
And the buffer part 203a of the buffer mechanism 22c is formed including the upper buffer rubber 200a, the lower buffer rubber 200b, the electromagnet 202, and the variable elastic body 206.
The other configuration is the same as that of the vibration isolator 22 shown in FIG. 2, and detailed description thereof is omitted as appropriate.
According to this configuration, the rigidity of the variable elastic body 206 can be changed by controlling the generation of the magnetic field by the electromagnet 202, and the rigidity of the buffer portion 203a of the buffer mechanism 22c provided with the variable elastic body 206 can be changed. .

  When the rotational speed of the rotating drum 3 (see FIG. 1) increases during the dehydration process of the washing machine 1 (see FIG. 1), the outer tub 2 (see FIG. 1) and the casing 1a (see FIG. 1) resonate in the left-right direction. When the rotation speed (resonance rotation speed) is reached, abnormal vibration and noise are generated in the housing 1a.

When the washing machine 1 (see FIG. 1) is regarded as one rigid body, the resonance rotational speed ωs is expressed by the following equation 1.

  In Equation (1), k is rigidity (spring constant), m is the mass of the vibration part, and ζ is the damping ratio. When the damping ratio ζ is constant as shown in the equation (1), the resonance rotational speed ωs is proportional to the square root of the stiffness k. In other words, the resonance rotational speed ωs can be changed by changing the rigidity k.

  FIG. 7 is a graph showing the relationship between the rotational speed ω of the rotating drum 3 (see FIG. 1) and the magnitude of the left-right amplitude in the washing machine 1 (see FIG. 1). For example, when the rigidity k of the washing machine 1 is k1, the left-right amplitude of the washing machine 1 peaks when the rotational speed ω of the rotary drum 3 is ωs1, as indicated by the solid line. That is, the resonance rotation speed ωs becomes ωs1 (first resonance rotation speed). When the rigidity k is k2 larger than k1, as shown by the broken line, the left-right amplitude of the washing machine 1 peaks when the rotational speed of the rotary drum 3 is ωs2 higher than ωs1. That is, the resonance rotation speed ωs becomes ωs2 (second resonance rotation speed). Thus, the resonance rotational speed ωs can be changed by changing the rigidity k of the washing machine 1.

Therefore, in the second embodiment, the rigidity k of the washing machine 1 is changed by changing the rigidity of the buffer portion 203a (see FIG. 6) of the buffer mechanism 22c, thereby changing the resonance rotational speed ωs, and the rotating drum 3 (FIG. 1) is avoided to coincide with the resonance rotational speed ωs.
According to this configuration, the rotating drum 3 does not rotate at the resonance rotational speed ωs, and the washing machine 1 (see FIG. 1) does not resonate. Therefore, it is possible to avoid the occurrence of left-right vibration having a peak left-right amplitude in the outer tub 2 (see FIG. 1), and vibration generated in the housing 1a can be suppressed.

  For example, when the rotational speed of the rotating drum 3 (see FIG. 1) increases during the dehydration process, when the rotational speed ω is low, the rigidity k of the washing machine 1 (see FIG. 1) is increased to increase the resonant rotational speed ωs. To do. Then, before the rotational speed ω of the rotating drum 3 reaches the increasing resonant rotational speed ωs, the rigidity k is decreased to make the resonant rotational speed ωs lower than the rotational speed ω of the rotating drum 3.

  Referring to FIG. 7, when the rotational speed ω of the rotary drum 3 (see FIG. 1) is lower than the first resonance rotational speed ωs1, the rigidity k of the washing machine 1 (see FIG. 1) is set to k2. When the rotational speed ω of the rotating drum 3 increases and exceeds the first resonance rotational speed ωs1, that is, the rotational speed ω of the rotating drum 3 reaches a predetermined switching rotational speed ωsc (ωs1 <ωsc <ωs2). At this time, the stiffness k is changed to k1 smaller than k2.

Thereafter, even if the rotational speed ω of the rotating drum 3 rises above the switching rotational speed ωsc, the resonant rotational speed ωs is changed to the first resonant rotational speed ωs1, and therefore the rotational speed ω of the rotating drum 3 is changed to the resonant rotational speed. It does not coincide with ωs.
According to this configuration, the rotation speed ω of the rotating drum 3 (see FIG. 1) is avoided from matching the resonance rotation speed ωs, and the occurrence of resonance in the washing machine 1 (see FIG. 1) can be suppressed. Therefore, vibration generated in the housing 1a (see FIG. 1) can be suppressed.

  In the second embodiment, as shown in FIG. 6, the housing-side buffer mechanism 22c1 including the variable elastic body 206 is used, and the generation of the magnetic field by the electromagnet 202 is controlled so that the rigidity of the buffer portion 203a of the housing-side buffer mechanism 22c1. The configuration is changed. Further, the outer tank side buffer mechanism 22c2 (see FIG. 1) that connects the vibration isolator 22 (see FIG. 1) and the outer tank 2 (see FIG. 1) has the same configuration as the housing side buffer mechanism 22c1. When the rigidity of the buffer portion 203a of the housing side buffer mechanism 22c1 and the outer tub side buffer mechanism 22c2 changes, the rigidity k of the washing machine 1 (see FIG. 1) changes. Therefore, by controlling the generation of the magnetic field by the electromagnet 202, The rigidity k of the washing machine 1 can be controlled.

  When the control device 6 (see FIG. 1) increases the rotational speed ω of the rotary drum 3 (see FIG. 1) in the dehydration process or the like, the shaft 4a (see FIG. 1) measured by the rotational speed detection device 50 (see FIG. 1). ) Is obtained as the rotational speed ω of the rotary drum 3. When the rotational speed ω of the rotating drum 3 is lower than the first resonance rotational speed ωs1, the supply of electric power to the electromagnet 202 (see FIG. 6) is stopped to extinguish the magnetic field. The rigidity of the variable elastic body 206 is recovered and the rigidity of the buffer portion 203a (see FIG. 6) of the housing side buffer mechanism 22c1 is increased. Similarly, the rigidity of the buffer portion 203a of the outer tank side buffer mechanism 22c2 (see FIG. 1) is increased.

  The control device 6 (see FIG. 1) further increases the rotational speed ω of the rotary drum 3 (see FIG. 1), and the rotational speed ω of the rotary drum 3 reaches a switching rotational speed ωsc higher than the first resonance rotational speed ωs1. Then, electric power is supplied to the electromagnet 202 (see FIG. 6) to generate a magnetic field. The variable elastic body 206 is placed in the magnetic field to reduce the rigidity, and the rigidity of the buffer portion 203a (see FIG. 6) of the housing-side buffer mechanism 22c1 is decreased. Similarly, the control device 6 reduces the rigidity of the buffer portion 203a of the outer tank side buffer mechanism 22c2 (see FIG. 1).

  When the rotational speed ω of the rotating drum 3 (see FIG. 1) is lower than the first resonance rotational speed ωs1, the housing side buffer mechanism 22c1 (see FIG. 1) and the buffer section 203a of the outer tank side buffer mechanism 22c2 (see FIG. 1) The rigidity is high, and the rigidity k of the washing machine 1 (see FIG. 1) is k2. At this time, the resonance rotation speed ωs is the second resonance rotation speed ωs2, and the rotation speed ω of the rotary drum 3 is lower than the resonance rotation speed ωs. Therefore, the washing machine 1 does not resonate and no vibration is generated in the housing 1a (see FIG. 1).

  When the rotational speed ω of the rotating drum 3 (see FIG. 1) increases and reaches a predetermined switching rotational speed ωsc higher than the first resonance rotational speed ωs1, the housing side buffer mechanism 22c1 and the outer tank side buffer mechanism 22c2 (see FIG. 1). The rigidity of the buffer portion 203a (see FIG. 6) becomes low, and the rigidity k of the washing machine 1 (see FIG. 1) becomes k1. Then, the resonance rotation speed ωs is changed to the first resonance rotation speed ωs1, and the rotation speed ω of the rotary drum 3 becomes higher than the resonance rotation speed ωs. Thereafter, even if the rotational speed ω of the rotating drum 3 increases, the rotational speed ω of the rotating drum 3 is higher than the resonant rotational speed ωs and does not coincide with the resonant rotational speed ωs. Therefore, the washing machine 1 does not resonate and no vibration is generated in the housing 1a (see FIG. 1).

The first resonance rotation speed ωs1 and the second resonance rotation speed ωs2 are eigenvalues determined by the rigidity of the buffer portion 203a (see FIG. 6) of the outer tank side buffer mechanism 22c2 (see FIG. 1).
The rigidity of the buffer 203a is a design value determined by the amount of magnetic field generated by the electromagnet 202 (see FIG. 6), the material of the variable elastic body 206, and the like.
Further, the switching rotational speed ωsc at which the control device 6 (see FIG. 1) changes the rigidity of the buffer portion 203a is, for example, left-right vibration that decreases from the peak when the rigidity k of the washing machine 1 is k1, and the rigidity k is k2. If the rotational speed is an intersection of left and right vibrations that sometimes rise toward the peak, the magnitude of the left and right vibrations before and after changing the rigidity k of the washing machine 1 can be suitably suppressed.

  As described above, in the second embodiment, even if the rotational speed ω of the rotary drum 3 (see FIG. 1) increases, the resonance of the washing machine 1 (see FIG. 1) does not coincide with the resonant rotational speed ωs. Can be avoided. And it can suppress that a vibration generate | occur | produces in the housing | casing 1a (refer FIG. 1).

  As described above, the description has been made based on the left-right vibration, but the second embodiment can also be applied to the front-rear vibration and the pruning vibration. For example, as shown in FIG. 8, when the rigidity k of the washing machine 1 (see FIG. 1) is k1, the peak of the longitudinal vibration is that the rotational speed ω of the rotating drum 3 (see FIG. 1) is ωs3. Further, when the rigidity k of the washing machine 1 is k2 which is larger than k1, the peak of the longitudinal vibration is that the rotational speed ω of the rotary drum 3 is ωs4 which is higher than ωs3. Since the longitudinal vibration generally occurs at a higher rotational speed than the lateral vibration, the rotational speed ωs3 at which the longitudinal vibration peaks when the rigidity k of the washing machine 1 is k1 is higher than the second resonance rotational speed ωs2. .

  In this case, the control device 6 (see FIG. 1) supplies power to the electromagnet 202 (see FIG. 6) when the rotational speed ω of the rotary drum 3 (see FIG. 1) exceeds the second resonance rotational speed ωs2. Stop and set the rigidity k of the washing machine 1 (see FIG. 1) to k2. When the rotational speed ω of the rotating drum 3 increases and exceeds ωs 3, the control device 6 supplies power to the electromagnet 202. The rigidity k of the washing machine 1 becomes k1, and the rotational speed at which the longitudinal vibration peaks is ωs3. Thereafter, even if the rotational speed ω of the rotary drum 3 increases, it does not coincide with the rotational speed at which the longitudinal vibration peaks. Therefore, the rotational speed ω of the rotating drum 3 does not coincide with the rotational speed at which the longitudinal vibration of the outer tub 2 (see FIG. 1) or the like peaks, and is generated in the housing 1a by the longitudinal vibration of the outer tub 2 or the like. Vibration can be suppressed.

  Further, the plowing vibration has a peak at a higher rotational speed than the longitudinal vibration, and the rotational speed at which the plowing vibration becomes a peak varies depending on the rigidity k of the washing machine 1 (see FIG. 1). Similarly to the vibration, it is possible to suppress the vibration generated in the housing 1a due to the ground vibration of the outer tub 2 (see FIG. 1) or the like.

  As described above, the washing machine 1 (see FIG. 1) according to the second embodiment changes the rigidity of the variable elastic body 206 shown in FIG. 6 to change the left and right generated in the outer tub 2 (see FIG. 1). Vibration generated in the housing 1a due to vibration, longitudinal vibration, and grinding vibration can be suppressed.

As a modification of the housing side buffer mechanism 22c1, for example, as shown in FIG. 9, a variable elastic body 206 having a ring shape may be arranged around the lower buffer rubber 200b.
As described above, since the amount of deformation around the shock absorbing rubber 200 is large when the vibration isolator 22 is tilted, the ring-shaped variable elastic body 206 is arranged, for example, around the lower shock absorbing rubber 200b. The effect equivalent to the configuration shown in FIG. Further, the amount of use of the variable elastic body 206 can be reduced, and the cost can be reduced.
Furthermore, the outer tank side buffer mechanism 22c2 (see FIG. 1) may be configured as shown in FIG.

  For example, as shown in FIG. 10, a variable elastic body 206 surrounded by an electromagnet 202 is provided between a locking portion 22g for locking the coil spring 22b and a base portion 22h provided on the rod 22e. If the stopper 22g is supported by the variable elastic body 206, the vertical rigidity of the vibration isolator 22 can be changed, and transmission of vertical vibration to the housing 1a (see FIG. 1) is suppressed. it can.

  Moreover, the washing machine 1 (refer FIG. 1) which concerns on 2nd Embodiment is the buffer part 203a (FIG. 6) of both the housing | casing side buffer mechanism 22c1 (refer FIG. 6) and the outer tank side buffer mechanism 22c2 (refer FIG. 1). However, for example, the rigidity of only the buffer part 203a of the housing side buffer mechanism 22c1 may be changed, or only the buffer part 203a of the outer tank side buffer mechanism 22c2 may be configured. You may comprise so that the rigidity of can be changed.

<< Third Embodiment >>
In the first embodiment, the shock absorber 22 (see FIG. 1) is connected to the housing 1a (see FIG. 1) and the outer tub 2 (see FIG. 1). The vibration of the housing 1a is suppressed by changing the viscosity of the portion 203 (see FIG. 2), and in the second embodiment, the buffer portion 203a (see FIG. 6) of the housing side buffer mechanism 22c1 and the outer tank side buffer mechanism 22c2. ) To suppress vibrations generated in the housing 1a.
In contrast, in the third embodiment, the housing-side buffer mechanism 22c1 that connects the vibration isolator 22 to the housing 1a and the outer tank-side buffer mechanism 22c2 that connects the vibration isolator 22 to the outer tank 2 are made of the same material. The material is composed of members having different damping forces (viscosity coefficients), and the damping force of the housing side buffer mechanism 22c1 is set larger than the damping force of the outer tank side buffer mechanism 22c2.

  As shown in FIG. 11, when a rotating body having an upper mass point Wt1 and a lower mass point Wt2 rotates, a primary mode in which the upper mass point Wt1 and the lower mass point Wt2 resonate in the same phase when the rotational speed is low is obtained. When the rotation speed further increases, a secondary mode in which the upper mass point Wt1 and the lower mass point Wt2 resonate in opposite phases occurs (FIG. 11 (b)). When the rotational speed further increases from the state where the secondary mode resonance has occurred, the vibration gradually decreases and the steady state is reached ((c) in FIG. 11). In the steady state, the magnitude of the vibration is small, and a vibration in which the vibrations of the primary mode and the secondary mode are combined is generated. That is, the lower mass point Wt2 is inclined and the upper mass point Wt1 is not inclined.

As shown in FIGS. 12A and 12B, the washing machine 1 is modeled with the center of gravity position (vibrating portion center of gravity position) of the outer tub 2 being the upper mass point Wt1 and the lower position of the outer tub 2 being the lower mass point Wt2. When the outer tank 2 is supported by the two vibration isolation devices 22, as shown in FIG. 12 (a), the outer tank 2 is inclined during resonance (primary mode). As shown in (b), the outer tub 2 is not tilted in a steady state.
In a state where the outer tub 2 is not inclined, the heights of the two outer tub side buffer mechanisms 22c2 are equal, and the deformation amounts of the outer tub side buffer mechanism 22c2 and the housing side buffer mechanism 22c1 are equal.
On the other hand, in the state where the outer tub 2 is inclined, the housing side buffer mechanism 22c1 is greatly deformed than the outer tub side buffer mechanism 22c2.

Therefore, when the outer tub 2 is not tilted, the damping energy of the outer tub side buffering mechanism 22c2 and the casing side buffering mechanism 22c1 is substantially equal, and the influence on the force transmitted from the outer tub 2 to the casing 1a (see FIG. 1). Is substantially equal between the outer tank side buffer mechanism 22c2 and the housing side buffer mechanism 22c1.
On the other hand, at the time of resonance in which the outer tub 2 is inclined, the deformation of the housing side buffer mechanism 22c1 is large, and the damping energy is larger than that of the outer tub side buffer mechanism 22c2.

Therefore, when suppressing the vibration transmitted from the outer tub 2 to the housing 1a (see FIG. 1) by increasing the damping force of the buffer mechanism 22c, the damping force of the housing side buffer mechanism 22c1 is larger than that of the outer tub side buffer mechanism 22c2. It is preferable to do.
Therefore, in the third embodiment, the housing side buffering mechanism 22c1 and the outer tank side buffering mechanism 22c2 are formed by the buffer rubber 200 made of the same material, and the shapes of the housing side buffering mechanism 22c1 and the outer tank side buffering mechanism 22c2 are changed. Thus, the damping force of the housing side buffer mechanism 22c1 is made larger than that of the outer tank side buffer mechanism 22c2. For example, by changing the area of the surface of the buffer rubber 200 to which the vibration isolator 22 is connected between the outer tank side buffer mechanism 22c2 and the housing side buffer mechanism 22c1, the outer tank side buffer mechanism 22c2 and the housing side buffer mechanism 22c1 The damping force can be changed.
Specifically, as shown in FIG. 13, the area S1 of the surface of the housing side shock absorbing mechanism 22c1 (the shock absorbing rubber 200) to which the vibration isolator 22 is connected is defined as the outer tank side shock absorbing mechanism 22c2 to which the vibration isolator 22 is connected. By making it larger than the area S2 of the surface of the (buffer rubber 200), the viscosity coefficient of the housing side buffer mechanism 22c1 becomes larger than the viscosity coefficient of the outer tank side buffer mechanism 22c2, and the damping force of the housing side buffer mechanism 22c1 is increased. It becomes larger than the damping force of the side buffer mechanism 22c2.

  Thus, the viscosity coefficient of the housing side buffer mechanism 22c1 (buffer rubber 200) is made larger than the viscosity coefficient of the outer tank side buffer mechanism 22c2 (buffer rubber 200), and the damping force of the housing side buffer mechanism 22c1 is increased. By making it larger than the mechanism 22c2, the resonance of the primary mode generated in the washing machine 1 can be absorbed by the housing-side buffer mechanism 22c1 and the outer tub-side buffer mechanism 22c2, and vibrations generated in the housing 1a can be suppressed.

  As described above, the washing machine 1 (see FIG. 1) according to the first embodiment is configured to connect the vibration isolator 22 (see FIG. 1) that supports the outer tub 2 (see FIG. 1) and the outer tub 2 to each other. The viscosity of the buffer portion 203 (see FIG. 2) of the tank-side buffer mechanism 22c2 and the viscosity of the buffer portion 203 of the housing-side buffer mechanism 22c1 that connects the vibration isolator 22 and the housing 1a (see FIG. 1) By changing according to the rotation speed (see FIG. 1), it is possible to suitably suppress the vibration generated in the housing 1a.

  Moreover, the washing machine 1 (refer FIG. 1) which concerns on 2nd Embodiment is the outer tub side buffer which connects the vibration isolator 22 (refer FIG. 1) and the outer tub 2 which support the outer tub 2 (refer FIG. 1). The rigidity of the buffer portion 203a (see FIG. 6) of the mechanism 22c2 and the rigidity of the buffer portion 203a of the housing-side buffer mechanism 22c1 that connects the vibration isolator 22 and the housing 1a (see FIG. 1) are represented by the rotating drum 3 (FIG. 1). The vibration generated in the housing 1a can be suitably suppressed by changing the rotation speed according to the reference).

  Moreover, the washing machine 1 (refer FIG. 1) which concerns on 3rd Embodiment is the damping force (viscosity) of the housing side buffer mechanism 22c1 which connects the vibration isolator 22 (refer FIG. 1) and the housing | casing 1a (refer FIG. 1). By making the coefficient greater than the damping force (viscosity coefficient) of the outer tank side buffer mechanism 22c2 that connects the vibration isolator 22 and the outer tank 2, the vibration generated in the housing 1a can be suitably suppressed.

  The first to third embodiments are not limited to the drum-type washing machine 1 shown in FIG. 1. For example, the vertical washing machine includes an outer tub and an inner tub that open upward. Is also applicable.

1 Washing machine 2 Outer tub 3 Rotating drum (inner tub)
6 Control device 22 Vibration isolator 22c Buffer mechanism 22c1 Housing side buffer mechanism 22c2 Outer tank side buffer mechanism 200 Buffer rubber (buffer member)
203, 203a Buffer part

Claims (6)

An outer tub disposed inside the housing and containing the inner tub;
An anti-vibration device that provides anti-vibration support for the outer tub to the housing,
In the washing machine in which the vibration isolator is connected to the housing and the outer tub via a buffer mechanism,
The washing machine according to claim 1, wherein the buffer portion of the buffer mechanism changes in rigidity or viscosity.   The washing machine according to claim 1, wherein rigidity or viscosity of a buffer portion of the buffer mechanism that connects the vibration isolator to the housing changes. A control device for changing the rigidity or viscosity of the buffer portion;
The washing machine according to claim 1 or 2, wherein the control device changes a rigidity or a viscosity of the buffer portion according to a rotation speed of the inner tub.   The controller increases the viscosity of the buffer when the rotation speed of the inner tank is equal to or lower than a predetermined rotation speed, and decreases the viscosity of the buffer when the rotation speed of the inner tank is higher than the predetermined rotation speed. The washing machine according to claim 3, wherein:   The control device increases the rigidity of the buffer when the rotation speed of the inner tank is equal to or lower than a predetermined rotation speed, and decreases the rigidity of the buffer when the rotation speed of the inner tank is higher than the predetermined rotation speed. The washing machine according to claim 3, wherein: An outer tub disposed inside the housing and containing the inner tub;
An anti-vibration device for isolating and supporting the outer tub on the housing;
An outer tank side buffer mechanism for connecting the vibration isolator to the outer tank;
In a washing machine having a housing-side buffer mechanism that connects the vibration isolator to the housing,
The shock-absorbing member provided in the outer-tank side shock-absorbing mechanism and the shock-absorbing device connected to the housing and the shock-absorbing member provided in the housing-side shock-absorbing mechanism and connecting the vibration isolating device to the housing are formed of the same material. In addition, the washing machine is characterized in that a viscosity coefficient of the buffer member provided in the housing side buffer mechanism is larger than a viscosity coefficient of the buffer member provided in the outer tub side buffer mechanism.

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