JPS6335278B2 - - Google Patents

Description

Detailed Description of the Invention (Technical Field) The present invention relates to a dehydration control device for a fully automatic washing machine, centrifugal dehydrator, etc.

(Prior art) Conventionally, the spin-drying operation was controlled by a spin-drying timer, but this spin-drying timer was set based on the user's intuition and experience, resulting in over- or under-spinning or damage to the cloth due to over-spinning. There was a problem.

(Purpose) The present invention has been made in view of the above points, and when water droplets of dehydration liquid squeezed out from cloth subjected to dehydration collide with a dehydration sensor and an output of a certain size or more is output from the sensor. By determining whether or not the output is generated within a certain period, and automatically controlling the dewatering operation based on the determination result, the conventional drawbacks can be overcome.

(Example) Examples of the present invention will be described below with reference to the drawings.

Figure 1 is a front view showing the main parts of the dehydration sensor.
FIG. 2 shows the same side view, showing a ceramic piezoelectric element 12 (hereinafter referred to as a piezoelectric element. Electrodes are formed on both sides of the piezoelectric element 12, respectively) and the piezoelectric element 1.
2 shows the external appearance of the metal diaphragm 11 and the electrode terminals 13 and 14, which are connected to one electrode surface of the metal diaphragm 11 and bonded together.

FIG. 3 shows the appearance of the dehydration sensor 10, where 15 is an electrically insulating case. 17a~
d is a stop hole.

FIG. 4 is a sectional view taken along line A-A' in FIG. 3, in which the piezoelectric element 12 and metal diaphragm 11 shown in FIG. Indicates the condition. 15a is a circular protrusion provided on the case.

FIG. 5 is a cross-sectional view of the main parts when the dehydration sensor 10 is attached to the dehydrator, in which 1 is the machine frame, and the machine frame 1 has a motor 2 that drives the dehydrator tank 5 via a cushioning material (for example, a spring) 4. is installed. The dewatering tank 5 is connected to the motor 2 by a shaft 3. Reference numeral 6 is a water receiving tank located on the outer periphery of the dewatering tank 5 for receiving the dehydrated liquid, and a drain pipe 7 is connected to a part of the bottom of the tank. The dehydration tank 5 has an appropriate number of holes 8a to 8d through which the dehydration liquid passes. Several dehydration sensors 10 (9 in this embodiment) are provided at the bottom of the dehydration tank 5.
The hole 8a is provided so as to face the hole 8a of the hole 8a.

FIG. 6 is an enlarged cross-sectional view of a main part showing a state in which the dehydration sensor 10 is attached. The case 15 of the dehydration sensor 10 is inserted into the screw 19 and the nut 2 through the gasket 18a in such a way as to cover the hole made in the water tank 6.
0, it is closely fixed to the water receiving tank 6. The protrusion 15a of the case 15 bites into the gasket 18a. 18b is also Patsukin. The arrows indicate where the water droplets collide.

FIG. 7 is a block diagram of the main parts of the electronic control circuit that controls the dehydration process, in which the detection section 21 is connected to the dehydration sensor 10.
an amplification circuit 22 for amplifying the output voltage of the dehydration sensor 10; and a comparison circuit 23 provided to compare with a constant voltage and output only when the voltage is higher than the constant voltage in order to eliminate a small output voltage from the dehydration sensor 10. When there is an output via the comparator circuit 23 (one output is for a short time), a peak value hold circuit 24 generates an output that is discharged in a longer time than that, and when the output exceeds a certain voltage, an L signal is generated. The comparator circuit 25 outputs an H signal when the output voltage falls below a certain voltage.

FIG. 9 shows a specific example of the electronic control circuit. In Figure 9, R ₁ to R ₁₃ are resistors, D ₁ to _{D 3} are diodes,
C ₁ and C ₂ are capacitors, 34 and 35 are operational amplifiers,
36 and 37 are comparators. V ₁ is the negative input of the comparator 36, V ₂ is the positive input of the comparator 37 when the output of the comparator 37 is high, and V ₃ is the negative input of the comparator 37 when the output of the comparator 37 is low.
This is the positive input of the comparator 37 at the time of .

Next, explanation will be given with reference to the output models shown in FIGS. 10a to 10c.

FIG. 10a shows the positive input of the comparator 36,
In other words, it indicates the output of the operational amplifier 34, and when a water droplet collides with the dehydration sensor 10, the operational amplifier 34
There is an output larger than normal from the comparator 36, and when this output exceeds the comparison level _V1 , an output is generated from the comparator 36. Based on the output of the comparator 36, an output as shown in FIG. 10b is input to the negative input of the comparator 37. When this negative input becomes more than _V2 ,
The output of the comparator 37 becomes an L signal as shown in FIG. 10c, and becomes an H signal when it becomes lower than _V3 . Therefore, when water droplets collide with the dehydration sensor 10 approximately periodically, as shown in FIG. 10b, once the output exceeds _V2 , it drops below _V3 due to discharge until the next water droplet collides with the dehydration sensor 10. To avoid this, the number of CR time points (in this example, C ₂ × R ₈
time constant) can be determined. Here, to show an example of the CR time constant, if the number of holes 8a in the dehydration tank 5 facing the dehydration sensor 10 is 9, and the rotation speed of the motor 2 is 1600 revolutions per minute in a steady state, C ₂ =
2.2μF, R ₈ = 47KΩ.

As a result, if an output of a certain magnitude or more is generated from the dehydration sensor 10 within a certain period, the signal shown in FIG. When it runs out, the 10th
The signal shown in Figure c becomes H. In this way, depending on whether the output signal of the comparator 37 is L or H, it can be determined whether an output of a certain magnitude or more is generated from the dehydration sensor 10 within a certain period.

As a result of this, the output signal of the comparator 37 becomes L while an output of a certain magnitude or more is generated within a certain period, and when the output of a certain or more magnitude stops, the output signal becomes L. It becomes H.
After this, even if an output of a certain magnitude or more suddenly occurs and the output signal of the comparator 37 becomes L,
Since it is determined that the occurrence has occurred beyond a certain period, the subsequent control circuit will no longer accept it. As a result, the dehydration completion point is controlled based on the point in time when the output signal of the comparator 37 changes from L to H.

On the other hand, there is a method that focuses only on the magnitude of the output from the dehydration sensor 10 (in other words, the operational amplifier 34) and determines the time when the output falls below a certain value as the point in time when the dehydration is completed.
Since it is affected by variations in the output size of
It takes time and effort to adjust the control circuit, and it becomes susceptible to noise caused by impacts other than water droplets and electrical noise. Therefore, in the present invention, a dehydration detection means is provided for determining whether or not an output of a certain magnitude or more is generated from the dehydration sensor 10 within a certain period, and based on the determination result, the dehydration completion point is determined. It is designed to control. In this way, the above-mentioned problems will not occur, and the dehydration time will be the same for dehydration under almost the same conditions, and the dehydration time will be determined depending on the type and amount of cloth to be dehydrated, so that the desired dehydration rate can be achieved. You can get the desired finish.

Next, the relationship between the output signal of the comparator 37 and the subsequent control circuit will be shown.

In FIG. 7, 26 is a start switch that starts the dehydration process, 100 is a controller composed of a microcomputer, and controller 10
The relationship between the basic configuration of 0 and the external circuit is shown in FIG.

101 is a CPU, 102 is a program/fixed data memory ROM, and 103 is a temporary storage memory.
RAM, 104 is a timer, and 105 is an I/O section (input/output section). 27 controls the motor 2 by the output of the controller 100.
This is a drive circuit that turns ON and OFF. In Fig. 7, a relay is assumed to be used in the drive circuit, and its contact point is 33.
30 and 32 are windings of the motor 2, and 31 is a capacitor. The output signal of the comparator 37 is input (I ₂ ) to the controller 100.

Next, an example of control of the dewatering operation will be explained according to the flowchart of FIG. 12. First, turn on the start switch 26. When the start switch 26 is confirmed to be ON with the L input of I ₁ , the output of O ₁ becomes H.
Then, the motor 2 is driven via the drive circuit 27, and then the timer 104 is started. When the timer data T becomes T≧10 seconds (meaning that the signal is not seen for 10 seconds), it is determined whether the input from the detection unit 21 (the input signal is H or L) is I ₂ =L.
If I ₂ is not L, wait for 40 seconds, and if it does not reach L within that time, it is determined that there is some kind of abnormality (for example, no cloth is inserted, the motor is not rotating normally, etc.), and motor 2 is turned off. The timer 104 is stopped and the timer data is cleared. On the other hand, if it does not reach 40 seconds and I ₂ = L, then
Wait until I ₂ =H, and when I ₂ =H, read the timer data T (the timer data at this time is _T1 ). From this T ₁ to the dehydration completion time T ₂ (T ₂ =
T ₁ ×5) is calculated. Next, the timer data T
Determine whether or not T≧T _2. If T≧T ₂ , dehydration is complete, so the output of _O1 is set to L, the motor 2 is stopped via the drive circuit 27, and the timer 10 is activated.
Stop 4 and clear the timer data.

Here, the above dehydration completion time T ₂ will be explained using the dehydration of 2 kg of ramen cloth as an example.

When the dehydration starts (0 seconds), the rotation speed of the motor 2 gradually increases, and water droplets of the dehydration liquid fly out from the dehydration tank 5 and collide with the dehydration sensor 10 for about 8 seconds (this time depends on the type and amount of fabric). However, after about 40 seconds (this time also varies depending on the type and amount of fabric, etc.), the amount of water removed suddenly decreases. The number of water droplets colliding with the dehydration sensor 10 decreases, and the output of the dehydration sensor 10 decreases because the water droplets become smaller. As shown in Figure 11, this point of about 40 seconds is the point where the dehydration rate changes from rapid to slow, and it may take several times (for example, 5 times) this time to actually squeeze it out. It is required from experiments. Therefore, in this example, T ₁ corresponds to 40 seconds, and T ₂ corresponds to T ₂ =T ₁ ×5.

In this way, since the dehydration operation can be automatically controlled, the problems that arise when relying on the user's intuition and experience as in the past, as well as the dehydration sensor 10.
There are no problems caused by variations in the magnitude of the output, and stable and appropriate dehydration can always be performed.

(Effects) As described above, in the present invention, when the water droplets of the dehydration liquid squeezed out from the cloth subjected to dehydration collide with the dehydration sensor and the output from the sensor exceeds a certain level, the output becomes constant. It detects what is occurring within the cycle, calculates the dehydration time based on the duration of the detection signal, and controls the dehydration operation based on the calculated dehydration time, so the amount of cloth to be dehydrated can be adjusted. You can always get the appropriate dehydration time according to your needs.
Therefore, stable and appropriate dehydration can always be performed regardless of the amount of cloth to be dehydrated, and the conventional drawbacks can be overcome.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, FIGS. 1 and 2 are front and side views showing the main parts of the dehydration sensor, FIG. 3 is a front view of the dehydration sensor, and FIG. 4 is A of FIG. 3. -A' sectional view, Figure 5 is a schematic cross-sectional configuration diagram of the dehydrator equipped with a dehydration sensor, Figure 6 is a sectional view showing the installed state of the dehydration sensor, Figure 7 is a block diagram of the main parts of the electronic control circuit, Figure 8 is a diagram showing the relationship between the controller and external circuit, Figure 9 is an electric circuit diagram of the detection section, Figures 10 a to c are diagrams showing the output model of each part, and Figure 11 is the temporal change in dehydration rate FIG. 12 is a dehydration control flowchart. 5: Dehydration tank, 10: Dehydration sensor, 21: Detection section, 100: Controller.

Claims (1)

[Claims] 1. A dehydration sensor that generates an electrical signal in response to a collision of dehydration liquid, a dehydration detection means that determines that an output of a certain magnitude or more is generated from the dehydration sensor within a certain period, and Calculate the dehydration time based on the duration of the detection signal of the detection means,
A dehydration control device comprising a control means for controlling a dehydration operation based on the calculated dehydration time.