JP2012249695A - Vibration isolating apparatus for drum-type washing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibration isolating apparatus for a drum-type washing machine, which can effectively reduce the vibration in multiple directions of a washing tank unit in the machine.SOLUTION: The vibration isolating apparatus for the drum type washing machine, including a rotating drum as a rotating inner tank, and a water tank 206 as an outer tank accommodating the rotating drum therein, for isolating the vibration of the washing tank 202 arranged in a washing machine body 200, comprises a dynamic damper 10 having a damper mass and a gum elastic body elastically supporting the damper mass, of which natural frequency in a Q1 direction as a main vibrating direction is tuned to an excitation frequency of 450 rpm or more in a high rotating range of the rotating drum during dewatering, the dynamic damper 10 being attached to the water tank 206 so as to be inclined so that the Q1 direction has an angle within a range of 30 to 60° with respect to a vertical direction.

Description

  The present invention relates to a vibration isolator for a drum type washing machine that is particularly suitable for application to a so-called oblique drum type washing machine in which the rotation axis of the rotary drum is inclined with respect to the vertical direction.

As a drum-type washing machine, it has a washing tub unit including a rotating drum as an inner tub that rotates around a rotation axis inclined with respect to the vertical direction, and a water tub as an outer tub that accommodates the rotating drum inside, 2. Description of the Related Art A so-called diagonal drum type washing machine is known in which laundry is placed in a rotating drum and the rotating drum is rotated to perform washing, rinsing, and dewatering processes.
In this oblique drum type washing machine, the washing tub unit is supported by a support device including a coil spring interposed between the washing tub unit and the washing machine body and a damper as a vibration damping member.

9 and 10 schematically show the oblique drum type washing machine together with the support structure of the washing tub unit.
In the figure, 200 is a washing machine body, 202 is a washing tub unit housed in the washing machine unit, and this washing tub unit 202 is an inner tub that rotates around an obliquely inclined rotation axis as shown in FIG. A rotating drum 204 and a water tank 206 as an outer tank that accommodates the rotating drum 204 are provided.
The water tank 206 is provided with a drive motor 208, and the drive motor 208 rotationally drives the rotary shaft 210 of the rotary drum 204.

In FIG. 9, reference numeral 212 denotes an upper suspension spring that forms a part of the support device, and is constituted by a tension coil spring, and the laundry tub unit 202 is elastically suspended by the suspension spring 212.
Reference numeral 214 denotes a lower support unit, and the washing tub unit 202 is elastically supported from below by the support unit 214.
The support unit 214 is formed by unitizing a piston-type oil damper 220, a compression coil spring 222, an upper rubber cushioning member 224, and a lower rubber cushioning member 226.

  The piston-type oil damper 220 has a piston slidably fitted in the cylinder 216, extends a rod 218 downward from the piston, and is based on the sliding movement of the piston in the vertical direction in the drawing. Thus, the oil in the cylinder 216 is viscously flowed, and the vibration is damped based on the viscous flow.

  The support unit 214 is fixed to a support fitting 228 extending from the washing tub unit 202 in the cylinder 216, and is fixed to a mounting plate 230 provided on the bottom 238 of the washing machine body 200 with a rod 218.

  By the way, in the oblique drum type washing machine, since the rotating drum is inclined obliquely, the laundry is likely to be unevenly distributed in the rotating drum, that is, it is easy to apply an uneven load to the rotating drum, and the rotating drum has an oblique rotation axis. As shown in FIG. 9B, by rotating around, by causing resonance with the springs and the like constituting the above-described support device, particularly at the initial start of the dehydration process (low rotation range up to about 300 rpm). The washing tub unit 202 swings greatly in all directions up and down, left and right, and front and rear (for example, about 25 mm in each direction), generates vibration with a large amplitude, and also in a high rotation range exceeding 450 rpm, the rotating drum 204 The vibration due to the excitation force when rotating is generated, and the vibration is transmitted from the washing tub unit 202 to the washing machine body 200 via the support device and further to the floor,濯機 body 200 and the floor has occurred a problem that vibration.

  The above is the case of the oblique drum type washing machine, but in the case of the horizontal drum type washing machine in which the rotating drum is in the horizontal direction (substantially horizontal direction), the water tank unit is accompanied by the rotation of the rotating drum, although not as much as the oblique drum type washing machine. However, there is a problem that it swings up and down and left and right, and it has the same problem as an oblique drum type washing machine.

  Conventionally, as a countermeasure against the vibration described above, by mounting a metal or concrete weight on the washing tub unit 202, the center of gravity (balance of the washing tub unit 202) is adjusted and the weight is increased. The vibration of the washing tub unit 202 is suppressed.

The vibration in the high rotation range is governed by the eccentric weight caused by the uneven distribution of the laundry in the rotating drum, the drum diameter of the rotating drum 204, the weight of the washing tub unit 202, etc. By adding a weight to 202 and increasing the weight of the weight, vibration can be reduced to some extent.
However, since the weight is responsible for balance adjustment and its weight is limited, the actual situation is that vibration reduction due to the addition of the weight cannot be realized sufficiently.

As a countermeasure against the above-described vibration, a dynamic damper may be attached to the washing tub unit 202, specifically, the water tub 206 instead of the weight.
As a method of using the dynamic damper in this case, its resonance frequency is tuned (matched) to a resonance frequency that causes the washing tub unit 202 to resonate with the spring or the like of the support device in a low rotation range. Although it is possible to eliminate or suppress using a dynamic damper, in this case, the resonance amplitude of the dynamic damper at the time of resonance is too large, and the dynamic damper reaches its endurance life early. As a result, an anti-resonance peak appears on the high-frequency side, and the anti-resonance adversely affects vibration suppression. Therefore, such a large displacement vibration in the low rotation range is suppressed by a dynamic damper. Is practically difficult.

  On the other hand, in the high rotation range, the vibration amplitude of the washing tub unit 202 is not as great as in the low rotation range, and it is considered effective to reduce the vibration of the washing tub unit 202 in the high rotation range by a dynamic damper.

  In particular, at the time of dehydration, the rotating drum gradually increases in rotational speed to finally reach the maximum and constant rotational speed, and the constant rotation of the rotating drum is performed while maintaining the maximum constant rotational speed. If the frequency is tuned to reduce the vibration during steady rotation, vibration at steady rotation that lasts for a long time compared to other rotations can be reduced over a long period of time. It is advantageous that the reduction can be effectively exhibited.

  In Patent Document 1 below, in a horizontal drum type washing machine in which a rotating drum rotates around a horizontal rotation axis, a point where a dynamic damper is attached to a washing tub unit, specifically a water tub, and a natural vibration of the dynamic damper. It is disclosed that the number is tuned to an excitation frequency in a high rotation range when the rotating drum is dewatered.

  However, the one disclosed in Patent Document 1 is one in which only one dynamic damper is added at a position directly below the water tub, and the laundry tub unit is vertically and horizontally and, more particularly, washed in an oblique drum type washing machine. The vibration in the front-rear direction of the tank unit, that is, the vibration in all directions cannot be reduced, and is still not sufficient as a vibration countermeasure.

Japanese Patent No. 2966123

  The present invention has been made in view of the circumstances as described above, and an object thereof is to provide a vibration isolator for a drum type washing machine that can effectively reduce vibrations in each direction of a washing tub unit in the drum type washing machine. It is a thing.

  Thus, the present invention comprises a rotating drum as an inner tub that rotates, and a water tub as an outer tub that accommodates the rotating drum inside, and a washing tub unit disposed inside the washing machine body. An anti-vibration device for a drum-type washing machine for anti-vibration, comprising a damper mass and a rubber elastic body that elastically supports the damper mass, and a first additional vibration system in a first direction that is a main vibration direction of the damper mass. The dynamic damper to be formed is tuned so that the natural frequency in the first direction is an excitation frequency in a high rotation range of 450 rpm or more of the rotating drum during dehydration, and the first direction is the vertical direction of the drum-type washing machine. On the other hand, it is attached to the water tank so as to have an angle in a range of 30 to 60 °.

  According to a second aspect of the present invention, in the first aspect, the dynamic damper has a second additional vibration in a second direction orthogonal to the first direction, which is a main vibration direction different from the first direction of the damper mass. The natural frequency in the second direction is equal to the natural frequency in the first direction, and the second direction faces the front-rear direction of the water tank. As described above, the dynamic damper is attached to the water tank.

  According to a third aspect of the present invention, in any one of the first and second aspects, the anti-resonance generation region associated with the resonance of the dynamic damper is set to be a higher rotation region than the maximum rotation number of the rotating drum. It is characterized by being.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the dynamic damper is attached to the water tank at an angular position of 45 ° from the horizontal direction around the rotation axis of the rotary drum.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the dynamic damper is attached to two or more of the water tanks.

  According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the dynamic damper is disposed on an axis that passes through the center of gravity of the washing tub unit and is orthogonal to the rotational axis of the rotary drum. And

Effects and effects of the invention

As described above, the present invention relates to a dynamic damper that forms the first additional vibration system in the first direction, and the vibration frequency of the rotating drum in a high rotation region of 450 rpm or higher when the natural frequency in the first direction is dehydrated. After being tuned, the first direction is inclined and attached to the water tank so that the first direction is at an angle in the range of 30 to 60 ° with respect to the vertical direction of the drum type washing machine.
ADVANTAGE OF THE INVENTION According to this invention, the vibration of the high rotation area of a washing tub unit can be reduced favorably by the dynamic damper attached to the water tub.

  In the present invention, since the dynamic damper is inclined and attached to the water tank so that the first direction has an angle in the range of 30 to 60 ° with respect to the vertical direction, the vertical direction of the water tank is determined by a single damper. And vibrations in the left-right direction can be reduced together.

  For example, when the dynamic damper is attached to the water tank at an angle where the first direction is 45 ° with respect to the vertical direction, when the magnitude of the damper effect when the dynamic damper vibrates in the first direction is P, A damper effect having a magnitude of Pcos 45 ° (0.71 P) in the vertical direction (vertical direction) and a damper effect having a magnitude of Psin 45 ° (0.71 P) in the horizontal direction (horizontal direction) can be obtained.

Here, two of the same dynamic dampers are used, one of which is attached to the upper or lower part of the water tank in the vertical direction, that is, in the state in which the first direction is vertical, and in the non-inclined state, and the other one Is attached to the left or right side of the water tank in the horizontal direction, that is, in a state where the first direction is in a horizontal direction, in a non-inclined state, and according to the present invention, each of the two dynamic dampers has an angle of 45 ° In comparison with the case of mounting at an inclination, the damper effect of P magnitude is obtained in the vertical direction (vertical direction) and the damper effect of P magnitude is obtained in the horizontal direction (horizontal direction).
On the other hand, in the latter case, the damper effect having a size of 2 × 0.71P = 1.42P in the vertical direction (vertical direction) and the same size of 1.42P in the horizontal direction (horizontal direction). A damper effect is obtained, and a larger damper effect is obtained in both the vertical and horizontal directions than the former, and the sum of the vertical and horizontal damper effects is also larger than that of the former.

  On the other hand, in the case where the mounting is inclined at a maximum angle of 60 ° with respect to the vertical direction, the magnitude of the damper effect in the left-right direction is P × 2 × sin 60 ° (= 0.87) = 1.74P in the same manner. The magnitude of the damper effect is P × 2 × cos 30 ° (= 0.5) = P, and the damper effect in the left-right direction is the same as that in the case of non-tilting mounting, while the magnitude of the damper effect in the vertical direction is the same. Can be made large.

On the other hand, when tilted with a minimum angle of 30 ° with respect to the vertical direction, the magnitude of the damper effect in the vertical direction is 1.74P, and the magnitude of the damper effect in the horizontal direction is P. In comparison, the magnitude of the damper effect in the vertical direction can be increased while the magnitude of the damper effect in the horizontal direction is made equal.
In any case, the total sum of the damper effects can be made larger than in the case of non-tilt mounting.

As described above, the present invention is very effective when two or more dynamic dampers are attached. However, in the present invention, a single dynamic damper can be attached to the water tank.
Even in this case, the sum of the damper effects in the vertical direction and the horizontal direction can be made larger than that in the case where a single dynamic damper is mounted in a non-tilt manner, and at least one of the vertical direction and the horizontal direction is It can be made more than half the size of a non-tilt mounted dynamic damper.

Here, it is desirable to tune the natural frequency of the dynamic damper so as to reduce the vibration at the maximum and constant steady-state rotational speed at which the rotary drum reaches the end during dehydration.
In particular, the natural frequency can be tuned to coincide with the excitation frequency at the steady rotation speed.
In this way, it is possible to continue reducing the vibrations in the upper, lower, left and right directions at the high rotation speed of the washing tub unit over the longest time.

  In the present invention, a dynamic damper can be attached in place of the conventionally added weight, and in this case, the vibration reducing effect by increasing the weight of the entire washing tub unit by the damper mass and the damper effect in the dynamic damper are achieved. In addition, the vibration reduction effect can be enhanced while suppressing an increase in cost due to attaching a separate component to the water tank.

  Next, a second aspect of the present invention provides a dynamic damper that forms a second additional vibration system in a second direction orthogonal to the first direction, and the natural frequency in the second direction is the natural frequency in the first direction. In addition to the natural frequency equivalent to the frequency, the dynamic damper is attached to the aquarium so that the second direction faces the front-rear direction of the aquarium. In this way, while using a single dynamic damper, It is possible to reduce vibrations in the three directions of the vertical direction, the horizontal direction, and the front-rear direction, that is, vibrations in a high rotation range in all directions.

Further, in this second aspect, since the natural frequency in the second direction is equal to the natural frequency in the first direction, the vertical direction, the left-right direction, and the front-rear direction of the washing tub unit at the same rotation number are provided. Vibration can be effectively reduced.
In particular, when the natural frequency of the dynamic damper is tuned (matched) to the excitation frequency at the steady rotation speed at the maximum rotation during dehydration, the upper and lower sides of the washing tub unit at a constant rotation that continues for a long time, The vibrations in the left and right and front and rear directions can be continuously reduced for a long time, which is effective.
In the present invention, the natural frequency in the second direction is equivalent to the natural frequency in the first direction, not only when both are strictly the same frequency, but the former is ± 10% of the natural frequency of the latter. Including the case of being within.

Since the present invention reduces vibrations at high rotation by the dynamic damper, the region of occurrence of anti-resonance associated with the resonance of the dynamic damper becomes a higher rotation region than the maximum rotation number of the rotating drum. (Claim 3).
In this way, even when the vibration is reduced by resonating the dynamic damper with the washing tub unit, the anti-resonance can be prevented from actually appearing, and the adverse effect due to the appearance of the anti-resonance can be prevented. Can be eliminated.

In the present invention, it is desirable that the dynamic damper is attached to the water tank at an angular position of 45 ° from the horizontal direction around the rotation axis of the rotary drum.
This position is a position where a wide dead space is generated between the washing machine main body and the water tub. Therefore, by attaching the dynamic damper to such a position, the dead space can be effectively used and the dynamic damper can be installed in the wide space. Can be attached.

As described above, the present invention is highly effective when the dynamic damper is attached to two or more water tanks (Claim 5).
In this case, a total of four dynamic dampers can be attached to each of the four positions at the 45 ° angular position with respect to the water tank.

In the present invention, it is also desirable that the dynamic damper is disposed on an axis that passes through the center of gravity of the washing tub unit and is orthogonal to the rotational axis of the rotary drum.
By doing in this way, it can suppress effectively that a rotating drum and by extension, a washing tub unit vibrate irregularly with the exciting force with respect to a rotating drum.

It is a cross-sectional view of the dynamic damper used for the vibration isolator of the diagonal drum type washing machine which is one Embodiment of this invention. It is a longitudinal cross-sectional view of the dynamic damper of FIG. It is the figure which showed the side structure of the diagonal drum type washing machine of the embodiment. It is the figure which showed the structure seen from the front of the diagonal drum type washing machine of the embodiment. It is the figure which showed the structure seen from the rear surface of the diagonal drum type washing machine of the embodiment. It is the figure which showed the attachment state of the dynamic damper of FIGS. It is explanatory drawing of the test method for confirming the effect when the dynamic damper 10 of FIG. 1 is attached. It is the figure which showed the test result. It is the figure which showed an example of the conventionally well-known diagonal drum type washing machine. FIG. 10 is a side sectional view of FIG. 9.

Next, embodiments of the present invention will be described in detail with reference to the drawings.
In FIG. 1, reference numeral 10 denotes a dynamic damper as an example used in the present embodiment, which has a metal case 12 in which a metal damper mass 14 is disposed.
The case 12 has a pair of plate-like side wall portions 16 that are parallel to each other, and a plate-like upper wall portion 18 and a lower wall portion 20 that are perpendicular to the pair of side wall portions 16 and extend parallel to each other. The whole has a cylindrical shape with a rectangular cross section which is long in the left-right direction with respect to the up-down direction in FIG.
The case 12 is covered with an inner surface covering rubber 22 whose entire inner surface is thin and has a uniform thickness.
Here, the inner surface covering rubber 22 is vulcanized and bonded to the case 12.
The case 12 has a length in the front-rear direction in the direction perpendicular to the paper surface of FIG. 1 (the vertical direction in FIG. 2) longer than the length in the left-right direction in FIG.
Here, the case 12 has the same wall thickness in all of the pair of side wall parts 16, the upper wall part 18 and the lower wall part 20.

The damper mass 14 has a block shape, and has a horizontal cross-sectional shape in which the horizontal dimension in FIG. 1 is larger than the vertical dimension in FIG. 1, and is perpendicular to the plane of FIG. The dimension in the vertical direction in FIG. 2 is equivalent to the dimension in the same direction in the case 12.
The block-shaped damper mass 14 having a rectangular cross section is coated with an outer surface covering rubber 24 whose entire outer surface is thin and has a uniform thickness. This outer surface covering rubber 24 is also integrally vulcanized and bonded to the damper mass 14.
The damper mass 14 is disposed at the center of the case 12. Specifically, the interval between the damper mass 14 and the upper wall portion 18 of the case 12 is equal to the interval between the damper mass 14 and the lower wall portion 20, and between the damper mass 14 and one side wall portion 16. And the distance between the other side wall portion 16 are equal.

The damper mass 14 and the pair of side wall portions 16 are connected to each other through the outer surface covering rubber 24 and the inner surface covering rubber 22 by rubber elastic bodies 26, 28, 30, and 32 arranged at four positions. The four rubber elastic bodies 26 to 32 elastically support the damper mass 14 so as to be sheared and deformed.
Here, the four rubber elastic bodies 26, 28, 30, and 32 all have the same cross-sectional shape and the same columnar height, and all of them are arranged at the same vertical position in FIG. Yes.

The rubber elastic bodies 26 and 28 are arranged at the same position in the front-rear direction (vertical direction in FIG. 2), and the rubber elastic bodies 30 and 32 are arranged at the same front-rear direction position.
That is, the rubber elastic bodies 26 and 28 are opposed to each other in the left-right direction in FIG. 1 at the same height position in FIG. 1 and at the same front-rear position as shown in FIG.

Further, the rubber elastic bodies 30 and 32 are also opposed to each other in the left-right direction in FIG. 1 at the same height position and the same front-rear direction position.
These four rubber elastic bodies 26, 28, 30, and 32 are all arranged with their axial directions orthogonal to the pair of side wall portions 16, that is, parallel to the upper wall portion 18 and the lower wall portion 20. ing.

The inner surface covering rubber 22 is provided with a semi-circular protrusion 34 that protrudes toward the damper mass 14 at positions inside the upper wall portion 18 and the lower wall portion 20.
These protrusions 34 are provided for buffering when the damper mass 14 strikes the upper wall 18 or the lower wall 20 vigorously, that is, for reducing the momentum.

In the dynamic damper 10 of this embodiment, the rubber elastic bodies 26 to 32 having a cylindrical shape are shear elastically deformed in a direction perpendicular to the height direction, and the Q1 direction (first direction) in FIG. 1 and the Q2 direction in FIG. The (second direction) is the main vibration direction in which the damper mass 14 vibrates greatly.
That is, the dynamic damper 10 is attached to a vibration isolation target, so that two additional vibration systems, that is, an additional vibration system in the Q1 direction (first additional vibration system) and an additional vibration system in the Q2 direction (second additional vibration system). Form.

In the present embodiment, the elastic elastic bodies 26 to 32 have the same spring constant in the Q1 direction and the spring constant in the Q2 direction, and therefore the natural frequency of the additional vibration system in the Q1 direction and the natural frequency of the additional vibration system in the Q2 direction. Is the same.
However, in the present embodiment, the natural frequency in the Q2 direction may not be exactly the same as the natural frequency in the Q1 direction, and may be slightly different within a range of ± 10%.

3-5 has shown the state which attached the dynamic damper 10 to the diagonal drum type washing machine.
In these drawings, reference numeral 36 denotes an oblique drum type washing machine, and its configuration is basically the same as that shown in FIG.
In the figure, reference numeral 200 denotes a washing machine body, and 202 denotes a washing tub unit.
The washing tub unit 202 has a water tub 206 as an outer tub, and a rotating drum 204 as an inner tub is rotatably provided therein.
Reference numeral 208 denotes a motor that rotationally drives the rotary drum 204, and reference numeral 238 denotes the bottom of the washing machine main body 200.
Here, in detail, the rotation axis of the rotating drum 204 inside the washing tub unit 202 is inclined at an angle θ with respect to the horizontal direction (here, θ = 20 °).

A suspension spring 212 is formed of a tension coil spring. The washing tub unit 202 is elastically suspended by the suspension spring 212, and a part of the load is elastically supported by the suspension spring 212. .
Here, the two suspension springs 212 are arranged at a predetermined angle.
Incidentally, 38 is the front wall of the washing machine body 200, 40 is the rear wall, 42 is the upper wall, 44 is the opening on the front side of the washing machine body 200, and 46 is the opening on the front side of the water tank 206. Shows the part.

Reference numeral 214 denotes a lower support unit, and the washing tub unit 202 is elastically supported from below by the support unit 214.
The support unit 214 is formed by unitizing a piston-type oil damper 220, a compression coil spring 222, an upper rubber cushioning member 224, and a lower rubber cushioning member 226.
Reference numeral 228 denotes a support fitting extending from the washing tub unit 202, and 230 denotes a mounting plate provided on the bottom 238 of the washing machine body 200.

In this embodiment, a total of four dynamic dampers 10 shown in FIGS. 1 and 2 are attached to the outer surface of the water tank 206 at four different positions. In this embodiment, the vibration isolator is constituted by a total of four dynamic dampers 10 attached to the water tank 206.
Here, the four dynamic dampers 10 are disposed on an axis that passes through the center of gravity of the washing tub unit 202 and is orthogonal to the rotational axis of the rotary drum 204.

Further, in the circumferential direction of the water tank, the four dynamic dampers 10 are positioned at an angle β from the left and right positions in the horizontal direction as shown in FIG. 4, that is, β from the horizontal direction around the rotation axis of the rotary drum 204. It is attached to the water tank 206 at an angular position.
In the present embodiment, β = 45 °. That is, the four dynamic dampers 10 are attached to the water tank 206 at 45 ° angle positions from the upper and lower positions in the vertical direction and the left and right positions in the horizontal direction on the circumference of the water tank 206.

As shown in FIGS. 4 and 5, the water tank 206 and the rotating drum 204 inside thereof are cylindrical, that is, circular in front view and rear view, while the washing machine main body 200 as a housing is in front. It has a quadrangular shape when viewed and viewed from the rear, and is wide in the portion between the water tub 206 and the washing machine main body 200 at 45 degrees from the top and bottom in the vertical direction and the left and right ends in the horizontal direction. Dead space has occurred.
The four dynamic dampers 10 are attached to the water tank 206 in these dead spaces, that is, using these dead spaces.

As shown in FIGS. 4 and 6, each dynamic damper 10 is also attached to the water tank 206 in such a direction that the Q1 direction forms an angle α with respect to the vertical direction.
In this embodiment, the angle α is 45 °.
However, the angle α may be another angle within the range of 30 to 60 °.
Each dynamic damper 10 is attached to the water tank 206 with the Q2 direction of FIG. However, the dynamic damper 10 is attached to the water tank 206 so that the direction (Q2 direction) is horizontal.

Each dynamic damper 10 is mounted so that the Q1 direction in FIG. 1 forms an angle α (here, α = 45 °) with respect to the vertical direction. As a result, the vertical direction (vertical direction) and the horizontal direction (horizontal direction). The damper effect is demonstrated to each of.
Specifically, when the magnitude of the damper effect in the Q1 direction of a single dynamic damper 10 is P, each dynamic damper 10 has a damper effect having a magnitude of Pcosα in the vertical direction and a magnitude of Psinα in the horizontal direction. Demonstrate the damper effect.
Specifically, α = 45 ° here, and thus each dynamic damper 10 exhibits a damper effect of 0.71 P in the vertical direction and a damper effect of 0.71 P in the horizontal direction.

  In this case, the sum of the magnitudes of the damper effects in the vertical direction (vertical direction) of the four dynamic dampers 10 is 2.84P, and the sum of the magnitudes of the damper effects in the horizontal direction (horizontal direction) is also 2. 84P, and the same two dynamic dampers 10 are arranged at the upper and lower positions of the water tank 206 with the Q1 direction oriented in the vertical direction, and further, the same two dynamic dampers 10 are arranged at the left and right ends of the water tank 206. A damper effect that is larger than 2P of the sum of the magnitudes of the damper effects in the vertical direction and 2P of the magnitude of the magnitude of the damper effects in the left and right directions obtained when the Q1 direction is arranged in the horizontal direction at the position is obtained. It is done.

  In addition, in this embodiment, each of the four dynamic dampers 10 exhibits a damper effect of size P in the horizontal front-rear direction.

  Accordingly, the natural frequency in the Q1 direction and the Q2 direction of the dynamic damper 10 is tuned (matched) with the excitation frequency in the high rotation range of 450 rpm or more of the rotating drum 204 during dehydration, so that the washing tub at high rotation speed is obtained. The vibrations in all directions of the unit 202 in the vertical direction, the horizontal direction, and the longitudinal direction can be effectively reduced.

  Moreover, in this embodiment, it replaces with the weight added conventionally, the dynamic damper 10 is attached, the vibration reduction effect by increasing the weight of the washing tub unit 202 whole by the damper mass 14, and the damper effect in the dynamic damper 10 In addition, the vibration reduction effect can be enhanced while suppressing an increase in cost due to attachment of a separate component to the water tank 206.

  In the present embodiment, the natural vibration frequencies of the dynamic damper 10 in the Q1 direction and the Q2 direction are reduced so as to reduce vibration when the rotating drum 204 finally rotates and reaches a steady rotation at a constant rotation speed. It can be tuned in advance, especially by tuning the natural frequency to the excitation frequency at the steady rotation speed of the maximum rotation (matching it), In particular, it is possible to continuously reduce vibrations of the washing tub unit 202 in the vertical, horizontal, and longitudinal directions for a long time, which is particularly effective.

  In this embodiment, the dynamic damper 10 is disposed on an axis that passes through the center of gravity of the washing tub unit 202 and is orthogonal to the rotation axis of the rotating drum 204. It is possible to effectively suppress the unit 202 from vibrating irregularly.

<Test example>
Vibration measurement is performed by attaching a weight of 3 kg (balance weight) to the top (top) of the front end of the water tank 206, and a weight of 1.5 kg to the left and right of the lower part of the tank at a position of 45 ° to the left and right. Went.
Further, as shown in FIG. 7, the dynamic dampers 10-1, 10-2, and 10-3 were attached to the same positions in the water tank 206 and replaced with weights, and vibration measurement was performed.

  For the uppermost dynamic damper 10-1, the mass of the damper mass 14 is 3kg, and for the dynamic dampers 10-2, 10-3 at 45 ° to the left and right from the position directly below the lower part, A damper mass 14 having a mass of 1.5 kg was used.

Regarding the dynamic damper, the uppermost dynamic damper 10-1 is mounted so that the Q1 direction is vertically downward, and the Q2 direction is the front-rear direction (horizontal direction). With respect to the dynamic dampers 10-2 and 10-3 at the 45 ° position, the water tank 206 is arranged so that the Q2 direction is the front-rear direction (horizontal direction) so that the Q1 direction is 45 ° with respect to the vertical direction. Attached.
Here, the dynamic dampers 10-1, 10-2 and 10-3 have their natural frequencies in the Q1 direction and Q2 direction matched to the excitation frequency (about 13 Hz) when the rotational speed of the rotary drum 204 is 780 rpm. .

The measurement was performed under the atmospheric temperature of room temperature (about 23 ° C.) by mounting an eccentric mass K having a mass of 200 g on the lower front end inside the rotating drum 204 and operating the washing machine in the dewatering mode.
The vibration was measured at the position R at the upper front end of the water tank 206.
The result is shown in FIG.

In the figure, the broken line indicates the vibration measurement result when the weight is mounted on the water tank 206, and the solid line indicates the state where the dynamic dampers 10-1, 10-2, and 10-3 are attached to the water tank 206 by replacing the weight. The vibration measurement result under is shown.
From these figures, it can be seen that the vibration reduction effect is enhanced by attaching the dynamic dampers 10-1, 10-2, and 10-3 instead of the weights.

8B and 8C, the vibration reduction effect by the dynamic damper is recognized as the vibration reduction effect by the dynamic dampers 10-1, 10-2, and 10-3. The vibration reduction effect obtained by the dynamic damper in the left and right vibration measurement results of (A) is mainly recognized as the vibration reduction effect by the dynamic dampers 10-2 and 10-3.
Therefore, even when the uppermost dynamic damper 10-1 is inclined according to this embodiment, a further vibration reduction effect can be expected in the left-right direction.

  In the dynamic dampers 10-1, 10-2, and 10-3, the natural frequency in the Q1 direction and the Q2 direction is higher than the maximum rotational speed of the rotary drum 204 in the anti-resonance region accompanying the resonance of the dynamic damper. Further, since it is set so as to be in a high rotation range, the anti-resonance peak does not appear in FIG.

  Although the embodiment of the present invention has been described in detail above, this is merely an example. In the present invention, the number of dynamic dampers is not limited to the above example, and is attached at an inclination angle different from the above example. Various other forms different from the above examples can be used, and the present invention can be applied to a horizontal drum type washing machine. For example, the present invention does not depart from the spirit of the present invention. It can be configured with various modifications.

DESCRIPTION OF SYMBOLS 10 Dynamic damper 14 Damper mass 26, 28, 30, 32 Rubber elastic body 36 Inclined drum type washing machine 200 Washing machine main body 202 Washing tub unit 204 Rotating drum 206 Water tank

Claims (6)

Anti-vibration of a drum-type washing machine comprising a rotating drum as a rotating inner tub and a water tub as an outer tub that accommodates the rotating drum inside, and that dampens a washing tub unit disposed inside the washing machine body A device,
A dynamic damper having a damper mass and a rubber elastic body elastically supporting the damper mass, and forming a first additional vibration system in a first direction which is a main vibration direction of the damper mass;
After tuning the natural frequency in the first direction to an excitation frequency in a high rotation range of 450 rpm or more of the rotating drum during dehydration,
A vibration isolator for a drum type washing machine, wherein the first type direction is attached to the water tank so as to be inclined at an angle in a range of 30 to 60 ° with respect to a vertical direction of the drum type washing machine. 2. The dynamic damper according to claim 1, wherein the dynamic damper forms a second additional vibration system in a second direction orthogonal to the first direction, which is a main vibration direction different from the first direction of the damper mass. And
After making the natural frequency in the second direction equal to the natural frequency in the first direction,
A vibration isolator for a drum-type washing machine, wherein the dynamic damper is attached to the water tank so that the second direction faces the front-rear direction of the water tank.   3. The method according to claim 1, wherein an anti-resonance region associated with the resonance of the dynamic damper is set to be a higher rotational region than the maximum rotational speed of the rotating drum. Anti-vibration device for drum-type washing machines.   4. The vibration isolator for a drum type washing machine according to any one of claims 1 to 3, wherein the dynamic damper is attached to the water tank at an angular position of 45 [deg.] From the horizontal direction around the rotation axis of the rotary drum. .   5. The vibration isolator for a drum type washing machine according to claim 1, wherein the dynamic damper is attached to two or more water tanks.   The drum-type washing machine according to any one of claims 1 to 5, wherein the dynamic damper is disposed on an axis that passes through the center of gravity of the washing tub unit and is orthogonal to the rotation axis of the rotary drum. Anti-vibration device.

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