JPH0255092A - Vibration isolating device for washing machine - Google Patents

Abstract

PURPOSE:To reduce the generation of vibration and noise by a method wherein the height of the inner side part of a balancer is increased to a value higher than that of the outer size part thereof, and a rate of change of a rectified centrifugal force due to a change of amplitude is increased. CONSTITUTION:A balancer 10 is formed in a hollow annular shape, and the interior of the balance is watertightly sealed with fluid in a volume ratio of, for example, approximate 50%. An effective height h1 of an inner size part is increased approximately 1.1 times as high as an effective height h2 of an outer size part, and the high h1 has width w up to 1/2 width W of the balancer 10. The free level of internal fluid when the balancer 10 is rotated with amplitude of 0 togetherwith a dehydrating drum 1 is a level (d), and when amplitude is relatively low, the free level is a level (e). When amplitude is relatively high, the free level is a level (f), and when amplitude is high, operation is made by means of the balancer having a higher height compared with a case in which it is low, and a high rectified centrifugal force is produced. This constitution realizes a washing machine which reduces the generation of abnormal vibration and noise even when an unbalance is produced by clothes in the position of any height.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vibration isolating device for a washing machine for reducing vibrations in a dehydration tank caused by unbalanced clothes.

BACKGROUND ART The structure of a conventional washing machine is shown in FIG. In the figure, numeral 1 denotes a dehydration tank having a stirring blade 7 at the inner bottom, and is located inside the outer tank 6. A motor 9 and a clutch mechanism section 8 are attached to the bottom of the outer tank 6, and these components are suspended and supported by the main body 2 via a compression spring 4. Further, in order to prevent imbalance, a balancer 6 was attached to the upper part of the dehydration tank 1, which had a hollow annular shape with a substantially rectangular cross section and had approximately 60 parts of fluid sealed therein in a watertight manner. The function of this balancer 6 is to reduce vibrations caused by the unevenness of clothes in the dehydration tank 1 by moving the internal fluid in a direction that reflects them.

Problems to be Solved by the Invention However, the amount of centrifugal force (hereinafter referred to as corrective centrifugal force) exerted by the balancer 6 of the conventional structure in the direction of correcting the unbalance of the clothing is generally proportional to the vibration amplitude of the dehydration tank 1. However, when clothing is biased at different heights relative to the balancer 6, there is a problem in that ideal vibration conditions cannot be obtained and abnormal vibrations and noise are generated.

As shown in Fig. 3, the moment (moment) M acting on the center of gravity G of the hanging part including the dehydration tank 1 is M = FL - f.
/ ・・・・・・・・・・・・・・・(
1) F: Centrifugal force due to unbalanced clothing L: Length from the center of gravity G to the point of action of F f: Corrective centrifugal force of the balancer e: Length from the center of gravity G to the point of action of f Expressed by equation (1) However, when this value is 0, it is a normal vibration state and there is little noise.

However, the above value varies depending on the condition of the clothing. For example, when there is a large amount of clothing, it is concentrated toward the top and is large, and when there is little clothing, it is concentrated toward the bottom and shows a small value, indicating dehydration. Sometimes, the moment M was not necessarily 0, but in most cases the moment M was operating with large variations between ■ and O, causing large vibrations and noise.

Therefore, an object of the present invention is to provide a balancer that can reduce changes in moment regardless of the amount of clothing, and to reduce vibration and noise.

Means for Solving the Problems In order to achieve the above object, the present invention makes the height of the inner diameter part of the balancer higher than the outer diameter part to increase the rate of change of the corrective centrifugal force due to the change in amplitude. be.

Effect With the above configuration, there is a large amount of items to be dehydrated, such as clothes, located above the dehydration tank, and the length L from the center of gravity to the point of action of centrifugal force is
When the amplitude of a part of the balancer becomes extremely large, a larger corrective centrifugal force than before is generated and the moment)
The absolute value of can be reduced. In addition, when the amount of material to be dehydrated is small and it is located below the dehydration tank, and the amplitude of a part of the balancer becomes small, a smaller corrective centrifugal force is generated than before, and the absolute value of the moment (M) is also reduced. This prevents or reduces the occurrence of abnormal vibration forms and noise.

Embodiment Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings.

As shown in FIG. 1, the washing machine of this embodiment has an outer tub 6 suspended from a main body 2 via a support rod 3 and a compression spring 4. The dehydration tank 1 rotatably disposed within the outer tank 6 has a balancer 10 on its upper part, and has stirring blades 7 rotatably disposed on its inner bottom. The stirring blades 7 and the dewatering tank 1 are selectively switched by a clutch mechanism 8, and the rotational force of a motor 9 is transmitted thereto. As shown in FIG. 2, the balancer 1o has a hollow annular shape, and there are approximately 6
Fluid is sealed watertight at a volume ratio of 0%. Also,
The effective height hl of the inner diameter part is higher than the effective height h2 of the outer diameter part and is about 1.1 times or more, and the height hl of the inner diameter part is less than or equal to % of the width W of the balancer 1o. It has a width W of .

Next, the operation of the above embodiment will be explained.

Generally, as shown in FIG. 3, a centrifugal force F generated by the unevenness of the clothes and a corrective centrifugal force exerted by the balancer 10 act on a dehydrating washing machine, and the magnitude of the centrifugal force F is larger. FIG. 4 shows a graph of the relationship between the moment M acting f'FMf on the center of gravity G of the hanging portion and the unbalance height L.

Assuming that the corrective centrifugal force f of the balancer 6 is constant, the line is indicated by A. In other words, when the clothes form an imbalance in the lower part L1 of the dehydration tank 1, generally FLl<f#, so the generated moment has a magnitude of □MA1. Furthermore, if the upper part of the clothing forms an L2 imbalance, FL2>fg, and the generated moment has a magnitude of 0MA2.

The vibration form of the suspension part in these states is shown in Fig. 5. For example, when M is O, the lower amplitude a1 is smaller than the lower amplitude (
a), and conversely, when the moment M is ■, (C
). Here, the most ideal vibration form is a form in which the lower amplitude and the lower amplitude are equal (Φ), the moment at this time is 0, and the noise is also the smallest.

In the above, it is assumed that the amount of corrective centrifugal force of the balancer 10 is constant, but in reality, the vibration form differs depending on the magnitude of moment) M, and the amplitude a1 of the balancer 10 section. Since the magnitude of a2 changes, the relationship between the moment M and the unbalance height L is shown by line B in FIG. 4 (&).

In the above state, even if the unbalance height L changes, the value of the moment M does not change significantly, and in order to reduce the noise by bringing the shape of the vibration closer to the shape of the mouth, as shown in the figure. Balancer 1 to have the characteristics of the C line.
It can be seen that it is sufficient to change the characteristics of o.

The conventional balancer 1o, which has a corrective centrifugal force proportional to the general amplitude, has a B line, so in order to change it to a C line, the characteristics of the balancer 1o should be changed to a higher amplitude than before when the amplitude is relatively large. If the corrective centrifugal force is present, but the amplitude is small, the characteristics may be changed to have a smaller corrective centrifugal force.

Here, the state of the balancer 1o in this embodiment will be explained with reference to FIG. When this balancer 10 has an amplitude of 0, the dehydration tank 1
The free water surface of the internal fluid is the O water surface when the amplitude is relatively small, and the free water surface of the internal fluid is the water surface when the amplitude is relatively small. Also,
When the amplitude is relatively large, a θ water surface is formed, and this e water surface has a free water surface that is higher by h3+h4 than the water surface (2) when the amplitude is small. Therefore, when the amplitude is large, compared to when the amplitude is small, it is possible to obtain a larger corrective centrifugal force since the balancer is operated with a higher height.

As described above, according to the present invention, it is possible to obtain a balancer 1o having the characteristics of the C line (in Fig. 4) in which the magnitude of the corrective centrifugal force varies greatly depending on the amplitude. Even if an imbalance occurs, a washing machine with low abnormal vibration and noise can be realized.

A balancer according to a second embodiment of the present invention is shown in FIG. In this embodiment, the balancer 11 (from the height of the inner diameter part P to the height H2 of the outer diameter part is formed not by a step but by a continuous straight line. This is because the change in the corrective centrifugal force due to the amplitude , has the characteristic of being continuous.

Effects of the Invention As described above, while conventional balancers generate a corrective centrifugal force proportional to the amplitude, the present invention provides a balancer in which the corrective centrifugal force changes more than the change in amplitude. Even if the unbalance position changes in the height direction, the generated moment can be reduced, and abnormal vibrations and noise can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a washing machine showing an embodiment of the present invention;
Figure 2 is an enlarged cross-sectional view of the bow sensor, Figure 3 is a schematic diagram showing the force acting on the hanging part, and Figure 4 (a) shows the relationship between the unbalance height L and the resulting moment (M). Figure 4 (b) is a diagram showing the relationship, Figure 4 (b) is a vibration form diagram at each moment, Figure 5 (,) is a plan view of the balancer showing the state of the internal fluid at each amplitude, and Figure 6 (b) is Figure 5. (a
), FIG. 6 is an enlarged sectional view of a part of the balancer according to the second embodiment of the present invention, and FIG. 7 is a vertical sectional view showing a conventional washing machine. 1...Dehydration tank, 2...Main body, 3...
...Support rod, 4...Compression spring, 6...
・Outer tank, 8...Clutch mechanism, 10.11...
...Balancer. Name of agent: Patent attorney Shigetaka Awano and 1 other person. , +5 to '9', 0--12 to 5 '-

Claims (1)

[Claims] A hanging part including a dehydration tank, an outer tank, and a clutch mechanism part is suspended from the main body via a spring, and a fluid balancer in which fluid is sealed in a watertight manner is provided above the dehydration tank. The effective height h_1 is the effective height h of the outer diameter part
A washing machine vibration isolation device higher than _2.