JPH0811158B2 - Washing machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention measures the distance to a water surface or laundry with ultrasonic waves, determines the amount of cloth based on the distance, sets a washing water level, and performs washing based on the water level. The present invention relates to a washing machine for carrying out.

2. Description of the Related Art Techniques for measuring distance using ultrasonic waves have been known for a long time, and various methods have been proposed for using ultrasonic waves in a washing machine to detect the amount of cloth and automatically set the water supply amount, etc. There is.

As an example, a method is known in which laundry is put in, the distance to the upper surface of the laundry is measured, and the laundry amount is determined based on the value to set the wash water level. As another example, there is known one provided with a sprinkler for sinking the laundry in order to improve the detection accuracy.

Also, after supplying water up to a certain water level, stir it to let the laundry adapt to water, measure the distance to the laundry,
There is also a method of setting the water level of the laundry by knowing the amount of the laundry by comparing with the distance (absolute water level) to the water surface at that time stored in advance.

Problems to be Solved by the Invention In such a conventional method, the measurement result varies depending on the state (including air) when the cloth is put in, the cloth shape, the cloth quality, etc. Can not do it. In addition, it is practically impossible to sufficiently sink the laundry with the sprinkler. Also, with the method of comparing with the absolute water level, it is difficult to accurately set the water level stored in advance due to the secular change of the water level sensor (often using a pressure switch). Therefore, if the degree of popping-out of the cloth is within the variation of the water level, it is difficult to distinguish whether the water is excessive or the cloth is popping out (see FIG. 3).

The present invention has been made in view of the above problems, and by considering the water level variation in the absolute water level, it is possible to provide a washing machine that sets the washing water level according to the amount of laundry accurately with less cloth messiness. Has an aim.

Means for solving the problems In order to solve the above problems, the washing machine of the present invention has a means for supplying water to the washing tub, a water level detecting means for detecting the water level, and a stirring means for accommodating the laundry and the water. Ultrasonic wave transmitting means provided above the washing tub, ultrasonic wave receiving means for receiving the ultrasonic wave reflected by the ultrasonic wave emitted by the ultrasonic wave transmitting means upon the water surface or the laundry, and the stirring means A control means for operating the ultrasonic wave transmitting means and operating the water supply means until the water level detecting means detects a predetermined water level, and the ultrasonic wave receiving means outputs a signal after the ultrasonic wave transmitting means operates. Counting means for calculating the time until the water level, an absolute water level storage means for storing an absolute water level obtained by adding a variation to the predetermined water level detected by the water level detection means, an output of the counting means and this storage means The absolute water level stored in the above, and the output of the counting means outputs when the ratio higher than the absolute water level is a predetermined value or more, and the water level by the output of the absolute water level comparison means. It comprises an optimum water level determining means for increasing the predetermined water level detected by the detecting means.

By the above-described configuration of the present invention, by measuring the distance to the upper surface of the laundry by ultrasonic waves, by comparing the data and the value considering the variation limit of the water level detection means in the absolute water level, in a small number of places Since the amount of laundry is determined by measuring the distance, it is possible to set the optimum water level with little cloth damage and with high accuracy.

Practical Example FIG. 1 is a block diagram showing an embodiment of a washing machine of the present invention.

In the figure, reference numeral 1 is an ultrasonic transmitter, which transmits ultrasonic waves toward a cloth surface or a water surface. Reference numeral 2 denotes an ultrasonic receiver, which receives ultrasonic waves transmitted from the ultrasonic transmitter 1 and reflected by the cloth surface or the water surface. The ultrasonic transmitter 1 and the ultrasonic receiver 2 are attached to a position above the washing tub 3 and slightly outside the center. 4 is a stirring means, which drives the stirring blades 16 to make the laundry and water blend in. Reference numeral 13 is a water level detecting means for detecting a predetermined water level. A water supply unit 14 supplies water to the washing tub 3 at the start of washing or during detection.

A microcomputer 15 has a control means 5, a counting means 6, an absolute water level storage means 7, an absolute water level comparison means 8, a calculation means 9, a storage means 10, a comparison means 11 and an optimum water level determination means 12. The control means 5 controls the water supply means at the start of washing.
When the water level detection means 13 detects a predetermined water level, the water supply means 14 is stopped and the water supply means 14 is stopped. Further, the stirring means 4 is operated for a predetermined time so that the water and the laundry are made to fit in with each other. Further, the control means 5 operates the agitation means 4 for a short time in order to scan the laundry, and after stopping the operation, the ultrasonic transmitter 1 is operated. The counting means 6 operates after the control means 5 operates the ultrasonic transmitter 1.
The time until the ultrasonic receiver 2 receives the ultrasonic waves reflected on the laundry or the water surface is counted. The absolute water level storage means 7 operates the ultrasonic transmitter 1 at the upper water level (the one in which a large amount of water enters) of the variation of each water level,
The time until the ultrasonic receiver 2 receives the ultrasonic waves reflected on the surface of the water is stored. The absolute water level comparison means 8 compares the data stored in the absolute water level storage means 7 with the output of the counting means 5, and when the output of the counting means 5 is shorter than the data stored in the absolute water level storage means 7 ( If the distance is short = the cloth is protruding beyond the upper limit of the variation in absolute water level), a signal is output to the optimum water level determining means 12. The calculating means 9 calculates the virtual water level by averaging the outputs of the counting means 6 at a plurality of points (scanning). Storage means 10
Stores the outputs of the counting means 6 at a plurality of locations. The comparison means 11 compares the output of the calculation means 9 and each count value stored in the storage means 10. Optimal water level determination means 12
Determines the optimum water level based on the output of the absolute water level comparison means 8 or the comparison means 11.

Next, the operation of the washing machine configured as described above will be described. FIG. 2 is a flow chart showing the flow of operation of the embodiment of the present invention. This washer has a low water level (24
), Low (32), medium (36), and high (40). At the start of washing, the laundry is put in the washing tub 3 and the water supply means 14 is operated by the control means 5 to supply water. Then, the water level detection means 13 continues to supply water until the low water level is detected. Since the bottom water level of this washing machine is low, the optimum water level detected is low (Fig. 2, F-1).

Next, the control means 5 operates the agitating means 4 and the agitating blade to pause the laundry to the right for 3 seconds, 3 seconds, and agitate to the left for 3 seconds. At this time, the laundry sinks sufficiently,
The air that had become familiar with the water and contained in it had gone out (Fig. 2, F-2).

Next, the control means 5 includes the stirring means 4 and the stirring blades 16.
Is operated for a short time and stopped, and then the ultrasonic transmitter 1 is operated to emit ultrasonic waves.

At the same time, the counting means 6 is operated to start counting. Then, when the ultrasonic receiver 2 receives the reflected wave returning from the laundry or the water surface, the counting is finished, and the counting means 6 stores the count value in the absolute water level comparing means 8, the calculating means 9, and the storing means 10. Output. This count value corresponds to the distance to the laundry or the water surface (F-3, F-
4). Although these operations are repeated 10 times, the upper limit value of the fluctuation of the absolute water level stored in the absolute water level storage means 8 and the count value of the absolute water level comparison means 8 (absolute water level) The time corresponding to the upper limit value when the water level varies in the direction of increasing from the initial value (see FIG. 3) is compared. If there are two cases where the count value of the counting means 6 is equal to or more than the upper limit value of the water level variation of the absolute water level, the optimum water level determination means 12 judges that the current detected water level is not optimum for the amount of laundry, and ranks the water level one rank. UP (F-11 to F-15). That is, it is possible to determine that the current detected water level is not optimal for the amount of laundry by measuring at least two places.

For example, when the laundry is fully rated and the low water level is being detected, the detection will be performed at the next low water level by measuring at least two times. −3,
Since the operation of F-4 does not have to be performed 10 times, the cloth is less likely to be damaged and the detection time can be shortened.

Of the 10 times of measurement, if the count value of the above-mentioned counting means 6 is equal to or more than the upper limit value of the water level variation of the absolute water level, and two or more points do not appear, the calculating means calculates the average value of the 10 count values. To take. This is the virtual water level (F-8 in FIG. 2). The comparing means 11 takes the difference between the count value at 10 places stored in the storage means 10 and the virtual water level and accumulates this difference (F in FIG. 2). −
9). In the optimum water level determining means, the cumulative value is compared with a predetermined value, and if it is equal to or more than the predetermined value, it is determined that this water level is not suitable for the amount of laundry, and water is supplied again (next water level, current water level). If it is small, set it to low. If it is medium, supply water to high and move to the next washing step.) The process of measuring and calculating the distance to the laundry with ultrasonic waves becomes the optimum water level. Repeat until If this cumulative value is less than or equal to a predetermined value, it is determined that this water level is suitable for the amount of laundry, detection is terminated at this point, and the process proceeds to the next washing step (F-10 to F- in FIG. 2). 1
Five).

That is, when the amount of laundry is large (relative to the detected water level), there is a portion where the laundry is considerably out of the water surface.
(The laundry is uneven when viewed from the top of the washing tub.) The count values at the 10 locations stored in the storage means 10 are not constant, and the accumulated deviation from the virtual water level becomes large. If the water level is optimum for the amount of laundry, the storage means 8
The count values at the 10 locations stored in are almost constant values, and the cumulative deviation from the virtual water level (equal to the distance to the water surface) is also small.

In this embodiment, four levels of water level, low, low, medium, and high, are determined, but it goes without saying that if the number of levels is increased, the optimum water level for laundry will be more accurate.

EFFECTS OF THE INVENTION As is clear from the above description of the embodiments, according to the present invention, the distance to the laundry measured by ultrasonic waves is compared with the upper limit value of the water level variation of the absolute water level stored in advance. If the amount of laundry to be detected is too large compared to the detected water level, it can be determined that the detected water level is not optimal for the laundry with a small number of measurements, so that it is possible to reduce the cloth mess and the detection time.

Further, in the present invention, the predetermined water level detected by the water level detecting means is added with the variation to obtain the absolute water level, which sufficiently functions even with respect to the variation of the water level detecting means, and makes an optimum decision. .

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a flow chart showing an operation flow of the embodiment of the present invention.
FIG. 3 is a diagram showing absolute water level and water level variation. 1 ... Ultrasonic transmitter, 2 ... Ultrasonic receiver, 3 ... Wash tub, 4 ... Stirring means, 5 ... Control means, 6 ... Counting means, 7 ... Absolute water level storage means, 8 ... ... absolute water level comparison means, 9 ... calculation means, 10 ... storage means, 11 ... comparison means, 12 ... optimal water level determination means, 13 ... water level detection means, 14
…… Water supply means, 15 …… Microcomputer, 16 ……
Stirring wings.

Claims (1)

[Claims] 1. A means for supplying water to a washing tub, a water level detecting means for detecting a water level, a stirring means for accommodating laundry with water, and an ultrasonic wave transmitting means provided above the washing tub, and the ultrasonic wave. The ultrasonic wave emitted by the transmitting means receives the ultrasonic wave reflected on the surface of the water or the laundry, the ultrasonic wave receiving means, the agitating means and the ultrasonic wave transmitting means are operated, and the predetermined water level is detected by the water level detecting means. Control means to operate the water supply means until it detects, a counting means to count the time from the operation of the ultrasonic transmission means to the output of the ultrasonic reception means, and the detection by the water level detection means The absolute water level storage means for storing the absolute water level obtained by adding the variation to the predetermined water level is compared with the output of the counting means and the absolute water level stored in this storage means, and the output of the counting means is Washing machine comprising an absolute water level comparing means for outputting when the ratio higher than the absolute water level is higher than a predetermined value, and an optimum water level determining means for increasing the predetermined water level detected by the water level detecting means by the output of the absolute water level comparing means. .