JPH0638877B2 - Optimal water level detector for washing machines - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for automatically determining a water level according to the amount of laundry in a washing machine.

2. Description of the Related Art Conventional optimum water level detectors for washing machines are equipped with water level detectors that can detect the wash water level in three levels: high, medium, and low, and the user can detect this water level according to the amount of laundry. The detected water level of the device was switched by means to operate it for each washing operation.

Problems to be Solved by the Invention In such a conventional method, since the user arbitrarily determines the amount of laundry, the amount of water is not appropriate, and when the amount is small, the laundry is easily damaged. There were drawbacks such as unnecessary use of detergent.

The present invention solves the above-mentioned conventional drawbacks, and provides an optimum water level detection device for a washing machine capable of automatically setting the required water amount according to the amount of laundry put in. To aim.

Means for Solving the Problems In order to solve the above problems, the present invention attaches an ultrasonic transceiver above and below the center of a washing tub and attaches the ultrasonic transceiver to an ultrasonic range finder. And a controller for controlling a drive device for driving a washing machine and a constant-time water supply device for driving a water supply valve drive device for supplying water in the washing tub according to data from the ultrasonic distance meter, The control device includes a scanning unit that performs a plurality of distance measurements by the ultrasonic range finder while the laundry tub is rotated once, a storage unit that stores a measurement distance at each distance measurement, and an output from the storage unit. It is determined whether the laundry is above or below the water surface at each distance measurement based on the distance measurement, and if the rate at which the laundry is below the water surface is above a certain level, the laundry tub It was determined that the water level inside was the optimum water level. And a control means for setting.

Operation With this configuration, when the laundry is put in the tub, water is supplied for a certain period of time, and then the motor is driven and the pulsator rotates, so that the cloth and water are made to fit. At this time, if the water level is optimum, the cloth sinks below the surface of the water, and if not, the cloth appears above the surface of the water, and the condition of the surface of the water is detected by ultrasonic waves to determine whether or not the cloth is above the surface of the water. By doing so, the control device determines whether the optimum water level or not. As a result, it becomes possible to automatically set the required amount of water according to the amount of laundry loaded.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. First
The figure is a block diagram of an embodiment of the present invention. 1 is a cloth for laundry, 2 is a pulsator, 3 is a washing tub, and 4 is an outer washing tub. 5 is a water supply valve, 6 is a water supply valve drive device, 7 is a constant time water supply device that drives the water supply valve drive device for a certain period of time to supply water to the washing tub, 8 is a control device that controls the constant time water supply device, and 9 and 10 are An ultrasonic wave transmitter / receiver 11 mounted above the washing tub and displaced from the center of the washing tub is an ultrasonic distance meter connected to the transceivers 9 and 10, and is connected to the control device 8. 12
Is a motor drive device that drives the mechanical device 13. Mechanical device
13 drives the pulsator 2, the washing tub 3 and the outer washing tub 4
It has a structure that can be rotated together. A scanning unit 14 is provided in the control device 8 and drives the motor drive device 12. 15 is a start switch,
By pressing this switch 15, the optimum water level detection operation of the washing machine is started. Reference numeral 16 denotes a control means which is a main part of the control device 8 and has a calculation / comparison function, a storage function and the like. Reference numeral 17 is a storage unit of the control device 16.

Next, the operation will be described. FIG. 2 shows a flow chart of this embodiment, and the operation will be described according to this flow chart. First, load the laundry into the washing tub (20). Then press the start switch 15 (21). Then, the control means 16 causes the constant-time water supply device 7 to operate and the water supply valve drive device 6 to operate,
The water supply valve 5 is opened to supply water to the washing tub 3 for a certain period of time (22).
When the water supply for the fixed time is completed, the control means 16 stops the signal to the constant time water supply device 7, and the motor drive device 12 and the mechanical device.
When a signal is sent to 13, the mechanical device 13 works to drive only the pulsator 12. That is, the pulsator 2 is driven, the water is stirred, and the cloth 1 is soaked in the water (23). When the cloth 1 is soaked in water and the water level is appropriate, the cloth 1 sinks below the water surface. When the driving of the pulsator 12 is completed, the control means 16 then sends a signal to the scanning means 14. Then, the scan signal sends a signal to the mechanical device 13 and the motor drive device 12. The mechanical device 13 serves as a mechanism for rotating the entire washing tub 3 without rotating the pulsator 2. Now, the washing means is rotated around the washing tub by 1 / n (24). Therefore, the scanning means 14 informs the control means 16 that the scanning has been performed for 1 / n. Upon receiving the signal, the control means 16 sends the signal to the ultrasonic range finder 11. An ultrasonic wave is emitted from the ultrasonic range finder 11 via the ultrasonic wave transmitter 9, and the reflected wave that hits the object (water is cloth) in the washing tub 3 returns to the ultrasonic wave receiver 10 to the ultrasonic range finder 11. Return. The ultrasonic rangefinder 11 measures the time from when the ultrasonic wave is transmitted until it is received, and the distance X
It is converted to (1 / n) and sent to the control means 16 (25). Control means 16
Then, it is stored in the storage unit 17 as X (1 / n) as the distance of the 1 / n round. Thereafter, this operation is repeated, and the control means 16 confirms "26 whether scanning has been completed n times" (26) (that is, it is determined whether the washing tub has completed one round). When the scan is completed n times, the storage unit 17 of the control means 16 stores n pieces of distance data corresponding to 1 / n frequency division of the washing tub. In other words, (1 / n, X (1 / n)), (2 / n, X (2 / n)), ... (n /
n, X (n / n)). Here, 1 / n, 2 / n, ... N / n indicate frequency division positions, and X (1 / n), X (2 / n), ... X (n / n) indicate distances. Next, the control means 16 statistically processes the distance measurement data by n times of ultrasonic waves, and judges whether or not there is a certain value within a certain constant value in the n times of data (27).

Since this is an important point, it will be described more specifically with reference to FIG. FIG. 3 shows the inside of the washing tub 3 as seen from above.
The whole tank is divided into eight (n = 8). Now, it is assumed that the ultrasonic wave transmitters / receivers 9 and 10 are located about 10 cm above the point in FIG. As a hypothesis, the tank is now divided into ~ points, and the cloth 1 is 3 cm (a) above the water surface only at that point. Then, if the above scanning operation is performed, then the distance is 7 cm,
Others are water, so you can measure a distance of 10 cm at ~. That is As described above, the storage unit of the control unit stores n pieces of data. Now, the n data are processed. Table 1 shows one example thereof.

That is, as shown in Table 1, the difference ΔX from other points is taken for each point data, and within a certain fixed value Count the number of points at (for example, | ΔX | 1 cm).

Now, let a constant rate of a number within a certain value be k (for example, k = 6), and a point having a number of this constant rate k or more is a constant rate l (here, l = 7) or more for all points. Check if there is. That is, in Table 1, there are 6 or more points at, and 7 points in total, and it can be determined that the water level is optimum. The constant rates k and l can be set freely, and statistical processing with various determination criteria is possible.

When the water level is not optimum, the above operation is repeated from the step of "Open the water supply valve and supply water for a certain time" (22) again. In this way, the optimum water level of the laundry in the washing machine is determined.

EFFECTS OF THE INVENTION As described above, according to the present invention, by the statistical processing by the ultrasonic distance meter and the control device having the washing tub scanning means, it is possible to determine what percentage of the entire tub the laundry comes out of the water surface. It detects and determines the optimum water level. By doing this, it is possible to determine the water level by taking into consideration the volume and shape of the cloth weight, as compared to the method that used to determine the water level only by weight in the past. It becomes possible to save water, etc., and its practical effect is extremely large.

[Brief description of drawings]

FIG. 1 is a block diagram of an optimum water level detection device for a washing machine according to an embodiment of the present invention, FIG. 2 is a flowchart thereof, and FIG. 3 is a top view for explaining statistical processing of measurement data by an ultrasonic range finder. It is the tank top view seen. DESCRIPTION OF SYMBOLS 1 ... Cloth, 2 ... Pulsator, 3 ... Washing tub, 6 ... Water supply valve drive device, 7 ... Constant time water supply device, 8 ... Control device, 9, 10 ... Ultrasonic transceiver, 11 ... Ultrasonic range finder, 12 ... Motor drive device, 14 ... Scan means, 16 ... Control means

Claims (1)

[Claims] 1. An ultrasonic transmitter / receiver is mounted above the washing tub so as to be displaced from the center of the laundry, the ultrasonic transmitter / receiver is connected to an ultrasonic range finder, and the washing tub is obtained based on the data from the ultrasonic range finder. A control device for controlling a constant-time water supply device for driving a water supply valve drive device for supplying water in the interior and a drive device for driving a washing machine is provided, and the control means is configured to perform the ultrasonic wave during one rotation of the washing tub. Scanning means for performing distance measurement by a rangefinder a plurality of times, a storage unit for storing the measured distance at each distance measurement, and the laundry on the water surface at each distance measurement time based on the output from the storage unit The water level in the washing tub is determined to be the optimum water level when the rate at which the laundry is judged to be below the water level is above a certain level. Optimal water level detector for washing machines.