JPH0369559B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a stirring blade disposed at the inner bottom of a washing tub. Conventional structure and its problems Conventionally, in Japan, so-called whirlpool washing machines have been put into practical use, in which stirring blades are installed at the bottom of the washing tub, and the rotation generates a swirling water stream to wash the clothes. has been made into In this type of washing machine, as shown in FIG. 1, an agitating blade a is installed in a manner that projects from the bottom c of the washing tub b into the tub b. Therefore, the cleaning power is very high in the part where the stirring blade a directly contacts the clothes, while the cleaning power is weak in the part of the clothing that is away from the stirring blade a. As a result, the washing becomes more uneven and the parts of the clothes that directly come into contact with the stirring blades a become more damaged. Further, the outer diameter d ₁ of the stirring blade a is about 1/2 or less than the inner diameter d ₂ of the washing tub b, and the rotation speed is set to about 300 revolutions per minute or more.
A small-diameter agitation blade a protruding into the washing tub b rotates at high speed, and the part of the clothes that directly hits the agitation blade a is hooked up and turned, twisting that part or the part close to that part to some extent, and washing the entire garment. It is designed to apply agitation force to clothes, especially clothes above washing tub b. For this reason, the clothes tend to get twisted a lot, and it takes a lot of effort to loosen the clothes when taking them out after washing or dehydrating them. In addition to the above, the stirring blades are housed in a non-protruding state from the bottom of the washing tub, and there is a concave substrate whose depth gradually increases from the outer periphery toward the center, and the upper surface of this substrate. A dehydrating/washing machine that has the most protrusions in the center, and the degree of protrusions gradually decreases toward the outer periphery, and the apex is continuous with the inner bottom of the washing tub. Stirring blades have been proposed. This stirring blade prevents the laundry from shifting in the washing tub.
It can be predicted that the effect of reducing vibration during spin-drying and the effect of not damaging laundry can be achieved. However, in order to improve the cleaning effect, it is necessary to form a water flow from the center side toward the outer circumferential side between the pterygoid ridges, but the above-mentioned conventional configuration does not specifically disclose this point. However, there are still concerns regarding cleaning. OBJECTS OF THE INVENTION The present invention provides an agitating blade for a washing machine that reduces the twisting of clothes and has an excellent cleaning effect. Structure of the Invention In order to achieve the above object, the present invention has the following features:
A base whose central part rises in a spherical shape, descends toward the outer periphery to form a horizontal surface, and further has an arc that rises from the horizontal surface toward the outer periphery;
The base includes a plurality of ridges provided approximately radially on the upper surface of the base, and the base has a configuration in which the base is connected to the above-mentioned circular arc, ascends by a circular arc smaller than the circular arc, and is connected to the outer peripheral portion, and The depth of the horizontal plane is set to about 10 to 20% of the radius of the base, and the outer diameter of the base is set to about 70 to 90% of the inner diameter of the washing tub. DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below based on the accompanying drawings. Figure 2 shows the overall configuration of a fully automatic washing machine, where 1 is the outer panel of the main body, 2 is a washing tub/dehydration tub (hereinafter referred to as the washing tub) with a large number of dehydration holes 2, and 4 is the washing tub 2. A stirring blade rotatably installed at the inner bottom of the 5
6 is a water tank, 6 is a balancer for keeping balance during dehydration, and 7 is an operation panel that houses switches, etc. 8 is a motor, and this rotational force is generated by a booley 9,
It passes through the belt 10 and the booley 11, is further decelerated by the deceleration drive mechanism section 12, and is transmitted to the stirring blade 4. 13 is a damper for absorbing dehydration vibration; 1
4 is a rod, 15 is a drain valve, and 16 is a drain hose. The overall configuration has been described above, and next, the specific configuration of the stirring blade 4 will be explained with reference to FIGS. 3 to 5. The stirring blade 4 has a hemispherical part 17 with a spherical rise at the center of the upper surface, and a base surface 18 descends toward the outer circumference, descends a certain distance, and becomes the base surface 18.
is a horizontal plane 19, and a first circular arc 22a that rises outward on a tangent from approximately the midpoint between the center portion 20 and the outer peripheral portion 21, and this first circular arc 22a
A base 23 having a curved surface that ascends by sequentially connecting second arcs 22b smaller than the first arc 22b from a position where the first arc 22b has risen to a certain extent, and a plurality of pieces integrally or integrally formed on the base 23. It consists of 24 mountains. And the top 26 of the mountain 24 is
From a position 25 near the midpoint between the center part 20 and the outer peripheral part 21, or slightly closer to the outer circumference than this, the outer peripheral side is connected to the base 23 by a substantially horizontal surface 27, and also near the midpoint or slightly closer to the outer circumferential direction. It descends from the position 25 toward the center 20 as shown at 28, and further moves between the position 25 and the center 20.
It has a lowest point 29 approximately in the middle of the region, and further rises from the lowest point 29 toward the central portion 20 as shown at 30, and is connected to the hemispherical portion 17. Here, the radius of the first and second circular arcs 22a and 22b is set to approximately 1/2 of the outer diameter of the stirring blade 4, that is, the base 23, and the radius of the second circular arc 22b is set to approximately 1/2 of the outer diameter of the stirring blade 4, that is, the base 23.
The radius is approximately 1/2 of the radius of the circular arc 22a. Further, the horizontal plane 19 is the deepest part of the base 23, and the depth H of this deepest part is 10 to 20% of the radius of the stirring blade. Next, the cross-sectional shape of the peak 24 is shown in FIG. 5, and A to H in FIG. 5 correspond to A to H in FIG. 3. The top part 26 and the base 23 are connected by a suitable curved surface 31, and the top part 26 is connected to the base 23.
is changing as shown in the figure. In addition, the outer diameter d ₁ of the stirring blade 4 is the inner diameter d ₂ of the washing tub 2.
If it is 1, it should be about 0.7 to 0.9, and it is installed at the bottom of the washing tub 2 as shown in FIG. Here, 32 is a fitting part attached to the rotating shaft, and 33 is a boss. The operation of the above configuration will be explained. The stirring blade 4 is rotated clockwise, paused, counterclockwise, and rotated at a relatively low speed at a rotation speed of approximately 200 revolutions per minute or less. What gives the washing effect to the laundry is the effect of the water flow generated by the rotation of the stirring blade 4 and the ridges 2 of the stirring blade 4.
4 can be roughly divided into two types: the effect of directly moving clothing. The water flow generated by the agitating blade 4 is as shown by the arrows in FIGS. The water rises from there to reach the wall surface of the washing tub 2, and further rises along this wall, becoming a large circular arc water flow above the stirring blades 4. Since the cross-sectional shape of the base 23 is a curved surface in which the first and second circular arcs 20 and 21 are connected outward from the horizontal surface 19, the water flow descending from the hemispherical portion 17 ascends smoothly through the horizontal surface 19. Changes into water flow. Since the water flow rises in the washing tub 2 and becomes a large circular arc water flow, it is extremely advantageous and is substantially different from the conventional configuration shown in FIG. 1, which produces a small whirlpool water flow.
Further, the sizes of the first and second arcs 22a and 22b are set appropriately, and are effective in forming an ascending water flow. Furthermore, regarding the depth H of the deepest part of the base 23,
As a result of various experiments, for the radius dimension of the stirring blade 4,
Good results were obtained in the range of 10 to 20%. Next, the effect of the pile of stirring blades 4 on directly moving the clothes will be described. Since no mountain is formed in the hemispherical part 17 at the center of the base 23, clothes will not get caught in this part, and the top 26 of the mountain 24 is equal to or equal to the outer peripheral part 21 of the stirring blade 4. Since there is a slight difference in height, there is no need to directly hang clothes there. Further, the top 26 of the mountain 24 extends outward from a position approximately in the vicinity of the midpoint from the center part 20 to the outer peripheral part 21 or a position slightly closer to the outer periphery in an approximately horizontal direction 27.
Since the part of the stirring blade 4 with the highest circumferential speed is like this, and the rotational speed is low, it is less likely that clothes will be directly hung there. In this way, the outer diameter d ₁ of the stirring blade 4, which has an effect based on its shape, is approximately 70 mm with respect to the inner diameter d ₂ of the washing tub 2.
~90%, and the rotation speed is approximately 200%.
By keeping the number of rotations to a minimum or less,
A wide and slow water flow is generated in the washing tub 2, producing the effect of slowly moving the washed clothes. Originally, in a whirlpool type washing machine, the action of moving the laundry is made up of two main elements: the element that moves the clothes in the water stream, and the element that spins the clothes directly by the stirring blades 4. This is the effect of cleaning. It gives rise to Therefore, if we talk about the effects brought about by these two elements, if the element that moves on the water flow is strong,
The clothes are in good condition and are less kinked and tangled, but the cleaning power is weak. A typical example of this is a jet washing machine pressurized by a pump. On the other hand, if the element of directly spinning the clothes with the agitating blade 4 is strong, uneven washing and damage to the clothes will be large.
Further, twisting and tangles become larger, but on the other hand, the cleaning effect becomes larger. It is desirable to maintain a balance between the above two factors, to minimize damage to clothes, to reduce twisting and tangling of clothes, and to ensure basic cleaning power. In this embodiment, compared to the conventional whirlpool type washing machine, the element of washing effect by water flow is increased, and the element of directly hanging clothes and stirring is reduced. By adopting the configuration of the above embodiment, as shown in the table below, when the cleaning effect (cleaning degree) is maintained at the same level as conventional products, uneven cleaning, clothing damage, kinking, and tangles of clothing are reduced. It was made.

[Table] Note that the cleanliness mentioned here is based on electric washing machine JIS-
It was measured by the test method specified in C-9606, and the cleaning unevenness was 40 times after 4 cleaning tests.
It is based on the standard deviation of the degree of cleanliness of each piece of contaminated cloth, and the damage to clothing indicates the weight loss (%) when gauze is washed 20 times. Next, FIG. 6 shows another embodiment in which the shape of the peak 24 is slightly different from this embodiment, and the shape is located approximately at the midpoint between the center portion 20 and the outer peripheral portion 21 or at a position slightly outward. 34 outwardly from its top 26
horizontally, and facing downward inwardly from the position 34, so as to be connected to the base 23 at approximately the midpoint between the position 34 and the central portion 20, which is also similar to this embodiment. It has the following effects. Further, in FIG. 6, the configuration other than the above is the same as that shown in FIG. 4, and the explanation thereof will be omitted. In this example, we have explained the case where a fully automatic washing machine is equipped with an agitating blade, but the same effect can be obtained even if it is installed in the washing tub of a two-tub washing machine that is equipped with a washing tub and a dewatering tub. It will be done. In this case, the washing tub usually has a substantially rectangular planar shape, and the inner diameter d ₂ of the washing tub described above can be replaced with the distance across opposite sides of the rectangular washing tub, and the same effect can be obtained. It is something to play. Effects of the Invention As is clear from the above examples, according to the present invention, the influence of the water flow can be increased compared to the conventional method, and the effect of directly hanging clothes on the stirring blade and spinning it can be reduced. It maintains detergency at a high level, suppresses uneven washing, damage to clothes, kinks, and tangles, and exhibits well-balanced washing performance. In particular, from the horizontal plane of the base, a first circular arc and a second circular arc smaller than the first circular arc are connected, which allows for smooth upward flow of water and improves the agitation performance of the cloth. , and the cleaning effect can be improved.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view showing the overall structure of a conventional washing machine, FIG. 2 is a longitudinal cross-sectional view showing the overall structure of a washing machine according to an embodiment of the present invention, and FIG. 3 is a plan view showing its stirring blade. , FIG. 4 is a sectional view taken along the line X-O-Y in FIG. 3, FIGS. FIG. 2... Washing tub, 4... Stirring blade, 17... Hemisphere, 19... Horizontal surface, 20... Center, 21...
Outer periphery, 22a, 22b...first and second arcs,
23...base, 24...mountain, 26...top.

Claims (1)

[Claims] 1. A base whose central part rises in a spherical shape, descends toward the outer periphery to form a horizontal surface, and further has an arc that rises from the horizontal surface toward the outer periphery;
The base includes a plurality of ridges provided approximately radially on the upper surface of the base, and the base has a configuration in which the base is connected to the above-mentioned circular arc, ascends by a circular arc smaller than the circular arc, and is connected to the outer peripheral portion, and The agitator for a washing machine, wherein the depth of the horizontal plane is set to about 10 to 20% of the radius of the base, and the outer diameter of the base is set to about 70 to 90% of the inner diameter of the washing tub. Wings.