JP3643778B2 - Washing machine weight detection method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a washing machine capable of detecting the weight of laundry inside a washing tub even during washing.
[0002]
[Prior art]
Conventionally, in a fully automatic washing machine, before the start of washing (water injection), the total weight D1 of the washing tub is measured in the state where the laundry is put, and the weight D of the washing tub is subtracted to put the laundry loaded. The weight C1 was calculated, washed with a water injection amount corresponding to the weight of the laundry, and rinsed.
[0003]
Therefore, even if the laundry is additionally input or a part is taken out after the water injection is started, the amount of water injection is not adjusted according to the added amount or the extracted amount.
[0004]
[Problems to be solved by the invention]
For this reason, when additional laundry is added after the start of water injection, there is an inconvenience that the amount of laundry increases relative to the amount of water injection, and sufficient washing is not easy.
On the other hand, when a part of the laundry is taken out after the start of water injection, the laundry is reduced with respect to the amount of water injected. In addition, there was an inconvenience that the time required for washing becomes longer.
[0005]
Further, in the conventional washing machine, as described above, since the weight of the laundry is determined based only on the weight difference (D1-D) of the washing tub before and after the laundry is thrown in, when the wet laundry is thrown in In addition, water contained in the laundry was also measured as the weight of the laundry. As a result, excessive water injection is performed, and the water is wasted as well as the case where a part of the laundry is taken out after the start of water injection.
[0006]
An object of the present invention is to provide a washing machine capable of washing and rinsing with an appropriate amount of water according to the increase or decrease of the amount of laundry even when the amount of laundry changes during washing.
[0007]
[Means for Solving the Problems]
In order to solve the above-described problems, a laundry weight detection method for a washing machine according to the present invention is a laundry tub comprising an inner tub into which laundry is charged and stirred by a pulsator, and an outer tub that rotatably supports the inner tub. Is a method of detecting the weight of the laundry of the washing machine housed in the washing machine casing,
Measuring the static load D1 of the laundry tub into which the laundry has been loaded, and detecting the static load C1 of the loaded laundry;
Pouring water into the washing tub;
Detecting a dynamic load D2 of a laundry tub containing laundry and water while rotating the inner tub and / or pulsator, and a time-series change waveform of the dynamic load D2.
A high-frequency component is extracted from the obtained change waveform of the dynamic load D2 to obtain a secondary vibration waveform, which is present in the laundry tub based on the dynamic load D2 and the secondary vibration waveform of the laundry tub including laundry and water. Determining a laundry load C2;
Have
[0008]
The dynamic load C2 of the laundry can be determined based on the dynamic load D2 of the laundry tub including the laundry and water and the amplitude of the secondary vibration waveform, and the dynamic load D2 of the laundry tub including the laundry and water, It is desirable to determine based on the total time that the amplitude of the secondary vibration waveform exceeds a predetermined threshold.
[0009]
In the washing machine control method of the present invention, a washing tub comprising an inner tub that is loaded with laundry and stirred by a pulsator and an outer tub that rotatably supports the inner tub is housed in the washing machine casing. A method for controlling a washing machine,
Measuring the static load D1 of the laundry tub into which the laundry has been loaded, and detecting the static load C1 of the loaded laundry;
Pouring water into the washing tub;
Detecting a dynamic load D2 of a laundry tub containing laundry and water while rotating the inner tub and / or pulsator, and a time-series change waveform of the dynamic load D2.
A high-frequency component is extracted from the obtained change waveform of the dynamic load D2 to obtain a secondary vibration waveform, which is present in the laundry tub based on the dynamic load D2 and the secondary vibration waveform of the laundry tub including laundry and water. Determining a laundry load C2;
Comparing the determined dynamic load C2 of the laundry with the static load C1 of the laundry measured before pouring, and adjusting the amount of water in the washing tub according to the difference;
Have
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The inventors, even if the total weight of water and laundry in the washing tub (20) is the same due to the difference in specific gravity and physical properties between water and cloth, the inner tub (22) and / or pulsator (stirring) It was found by the following test that a difference occurred in the time-series change in the weight of the washing tub (20) accompanying the rotation of the wing (60).
[0011]
In the test, the total weight of the laundry and water put into the washing tub (20) is 41 kg (corresponding to the high water level of a normal washing machine), and the weight of the laundry (cotton cloth with a density of 1.5 g / cm ³ ) is measured. It changed from 0g-2016g, and it implemented by rotating a pulsator (60) forward / reversely with the motor (62) which is a drive means. The motor (62) was controlled to stop for the first 5 seconds, reversely rotate for 10 seconds, then forwardly rotate for 10 seconds, and then stopped for 5 seconds.
[0012]
Meanwhile, the change of the dynamic load D2 generated in the washing tub (20) was measured by the load detector (70). The load detector (70) was a load cell (LM-20A manufactured by Kyowa Denki Co., Ltd.), and the sampling frequency was 1 kHz. Although the output of the load cell is displayed as a voltage below, 0.2V can be converted to 1 kgf (9.8 N).
The obtained results are shown in FIGS. Referring to the figure, as the weight ratio of the laundry increases, the secondary vibration (the high frequency of the waveform) at the portion where the rotation of the motor (62) changes from the reverse rotation to the normal rotation (the portion where the elapsed time is 15 to 20 seconds). It can be seen that the component is small.
In order to examine the change in secondary vibration in detail, the output of the load cell obtained immediately after switching the rotation of the motor (62) from reverse rotation to normal rotation (elapsed time 15 to 25 seconds) is 30 Hz. Observed through a high-pass filter. As a result, as shown in FIGS. 8 to 12, it was found that the lower the ratio of the weight of the laundry, the larger the secondary vibration amplitude and the longer it takes to converge. In contrast, it was found that the higher the ratio of the weight of the laundry, the smaller the secondary vibration amplitude and the faster the convergence.
[0013]
As described above, the secondary vibration becomes smaller as the weight ratio of the laundry becomes higher. In the water, the laundry functions to suppress minute vibrations caused by rotation and reversal of the rotation direction compared to water. This is probably because of this.
[0014]
Based on these results, the relationship between the total time (integrated time) in which the secondary vibration amplitude was 0.05 V or more and the weight C1 of the loaded laundry was graphed. As shown in FIG. A graph was obtained in which the integration time decreased as the weight of the object increased.
Similarly, in the experiment in which the total weight of the laundry and water is 32 kg (corresponding to the low water level of a normal washing machine) and the motor (62) is rotated in the same manner as described above, the weight of the loaded laundry is changed. As a result, a monotonically decreasing graph was obtained as shown in FIG.
[0015]
That is, it was found that the weight of the loaded laundry can be calculated by detecting the secondary vibration of the load change generated in the washing tub (20) after reversing the rotation of the motor (62).
[0016]
The obtained result is stored in the microcomputer (80) (described later) of the washing machine (10), and the weight of the laundry is appropriately measured during the washing, and the amount of water is measured with respect to the measured laundry weight. By adjusting, it is possible to provide a washing machine (10) that can perform washing with an optimal amount of water in accordance with the added amount and the taken-out amount even if the laundry is additionally charged or taken out after water injection.
[0017]
[Example 1]
FIG. 1 is a side sectional view of the washing machine (10). As shown in FIG. 1, the washing machine (10) is configured such that a washing tub (20) in which washing, rinsing, and dehydration are performed is accommodated in a housing (12) that surrounds the outer periphery.
The washing tub (20) includes an inner tub (22) into which laundry is put and an outer tub (24) that covers the outer periphery of the inner tub (22).
The outer tub (24) is formed at the center of the casing (12) by suspension rods (30) and (30) (only two are shown in FIG. 1) attached to the upper four corners of the casing (12). It is supported by suspension. A drain pipe (40) having a drain valve (42) serving as a drain means is connected to the bottom of the outer tub (24), and water in the washing tub (20) is drained through the drain pipe (40). Discharge to the outside.
The inner tank (22) is rotatably accommodated inside the outer tank (24). The inner tub (22) is a bottomed cylindrical body in which a number of dewatering holes (not shown) are opened in the peripheral wall, and a pulsator (60) for stirring laundry on the central bottom surface of the inner tub (22) Is deployed. The pulsator (60) and the inner tank (22) are connected via a motor (62) as a driving means attached to the lower surface of the outer tank (24), a speed reducer (64), and a clutch (66). By switching (66), only the pulsator (60) is rotated for easy washing, and both the pulsator (60) and the inner tank (22) are rotated together for dehydration.
[0018]
The suspension rod (30) (30) passes through a lower seat (26) (26) whose lower end protrudes outward from the lower portion of the outer tub (24), and the suspension rod (30) (30) Compression coil springs (34) and (34) for vibration isolation are fitted between the stoppers (32) and (32) of the front end of each of the two and the lower seats (26) and (26).
The upper ends of the suspension rods (30) and (30) pass through upper receiving seats (14) and (14) that project inward from the upper portion of the housing (12), and the upper ends are received at the tip. A retaining member (36) (36) for preventing the seat (14) from falling off is attached.
[0019]
Among the suspension rods (30), one suspension rod (30) has a load detection that detects the weight acting on the washing tub (20) between the upper seat (14) and the retaining member (36). A vessel (70) is in place.
As the load detector (70), a force sensor using a magnetostrictive element can be used in addition to the load cell described above.
[0020]
Water injection means for injecting water into the inner tank (22) is disposed on the upper part of the inner tank (22). As shown in FIG. 1, the water injection means includes a water injection pipe (50) and a water injection valve (52), and the water injection pipe (50) is connected to a faucet of the water supply.
[0021]
The electrical system of the washing machine (10) will be described with reference to FIG.
All the control and calculation of the washing machine are performed by a control means (8) mainly composed of a microcomputer (hereinafter referred to as "microcomputer") (80). The control means (8) is arranged at a suitable place in the washing machine (10), and the microcomputer (80) includes a CPU, a memory, an arithmetic circuit, a high-pass filter, etc. (all not shown). The washing program of the present invention, a normal washing program, and other programs necessary for each control are stored. Further, as described above, the memory stores the memory table indicating the relationship between the threshold value of the secondary vibration amplitude with respect to the dynamic load D2 of the washing tub (20), and the optimal water injection amount for the laundry weight C1. It includes a memory table and other memory tables shown below.
[0022]
As shown in FIG. 2, the microcomputer (80) includes an operation unit (81), a display unit (82), a valve control circuit (83), a sensor circuit (84), a motor drive circuit (85), a clutch control circuit (86 ) Is electrically connected.
[0023]
All operation commands that the user performs to the washing machine (10) are input via the operation unit (81), and the operation result, the progress of washing, the remaining time, the appropriate amount of detergent to be introduced, etc. are displayed on the display unit (82 ) Is displayed.
[0024]
The sensor circuit (84) is electrically connected to a load detector (70) such as a load cell, and transmits the load value detected by the load detector (70) to the microcomputer (80). The microcomputer (80) takes out the high frequency component (secondary vibration) of the time-series change in the weight of the washing tub (20) with a high-pass filter, and counts the total time exceeding the threshold stored in the table. .
[0025]
The valve control circuit (83) is a circuit for controlling the opening and closing of the water injection valve (52) and the drain valve (42) described above. Based on the memory table of the microcomputer (80), the water injection valve (52) is turned on during water injection. Open and pour the required amount of tap water into the washing tub (20). Further, when draining, the drain valve (42) is opened to drain from the washing tub (20).
[0026]
The motor drive circuit (85) is electrically connected to the motor (62), and controls normal rotation, reverse rotation, and stop of the motor (62) in accordance with a command from the microcomputer (80).
[0027]
The clutch control circuit (86) is electrically connected to the clutch (66), controls the switching of the clutch (66) according to a command from the microcomputer (80), and controls the rotation of the motor (62) to the pulsator (60). Only, or transmitted to the pulsator (60) and the inner tank (22).
[0028]
The operation of the washing machine (10) having the above configuration will be described with reference to the flowchart of FIG.
When a user inputs dry laundry (wet laundry is shown in Example 2) (step 1) and inputs a washing start command from the operation unit (81), first, the load detector (70) The static load C1 of the laundry put in using is measured (step 2). The measurement of the static load C1 is preferably performed in a state where the inner tank (22) and the pulsator (60) are not rotating.
When a load cell is used as the load detector (70), the output from the load detector (70) is expressed in voltage, so the microcomputer (80) converts the weight according to the output voltage of the load detector (70). Then, by subtracting the weight D of the washing tub (20) from the obtained weight D1, the static load C1 in the dry state of the loaded laundry is calculated.
[0029]
Next, in accordance with the load C1 of the laundry calculated in step 2, the microcomputer (80) determines the amount of water injection using the memory table (step 3), and supplies the water injection valve (52 to the valve control circuit (83). ) Is released and water is injected (step 4).
When the predetermined amount of water injection is completed, the water injection valve (52) is closed and the washing process is executed (step 5). In the washing process, the clutch (66) is switched to rotate only the pulsator (60), and in that state, the motor (62) is rotated forward and reverse, and the rotation direction of the pulsator (60) is reversed from reverse rotation to forward rotation. The change of the dynamic load D2 at the time of reading is read out in time series at a predetermined sampling frequency using the load detector (70) (see FIGS. 3 to 7), and the microcomputer (80) is passed through the sensor circuit (84). Send to.
[0030]
The microcomputer (80) extracts a high frequency component (secondary vibration waveform) from the obtained time series weight D2 change waveform (dynamic load waveform) with a high pass filter as shown in FIGS. Then, the total of the time when the secondary vibration waveform exceeds the predetermined threshold (0.05 V in the embodiment) is calculated, and the weight ratio α occupied by the laundry is derived from the total time. The relationship between the total time when the secondary vibration waveform exceeds the threshold and the ratio α is stored in advance in the memory table of the microcomputer (80).
When the weight ratio α of the obtained laundry is multiplied by the water in the washing tub (10) and the dynamic load (D2-D) of the laundry (α × (D2-D)), the dynamic load C2 of the laundry is Calculated (step 6).
[0031]
After calculating the dynamic load C2 of the laundry, it is determined whether or not the laundry has been added or removed in the washing step.
Specifically, the calculated dynamic load C2 of the laundry is compared with the first measured static load C1 of the laundry.
When the dynamic load C2 is larger than the static load C1, it is determined that the laundry has been additionally charged after water injection (Yes in Step 7), and the injection corresponding to the dynamic load C2 stored in the memory table is performed again. Water injection is performed by opening the water injection valve (52) so that the amount of water (step 3) is reached (step 4).
On the contrary, when the dynamic load C2 is equal to or less than the static load C1, the process proceeds to the rinsing process (No in Step 7 and Step 8). In addition, when the dynamic load C2 is smaller than the static load C1, it returns to step 4, and it changes to water injection, and you may make it open | release drain valve (42) and to drain only an unnecessary part.
[0032]
Although explanations after the rinsing step and the dehydrating step are omitted, it is desirable to adjust the amount of water in the rinsing step as well by measuring the dynamic load of the laundry.
[0033]
[Example 2]
FIG. 16 is a flowchart showing another embodiment of the present invention. In Example 1, although the case where the dry laundry was thrown in was demonstrated, in Example 2, the case where the wet laundry is thrown in is demonstrated.
For the parts common to the first embodiment, the step numbers in the flowchart in FIG.
When wet laundry is put into the washing tub (20) (step 10), the load C1 of the laundry is measured as in step 2 (step 11). Here, since the load C1 is the load of the wet laundry, it is measured heavier than the load of the dry laundry.
[0034]
Next, as in step 3, the microcomputer (80) determines the amount of water injection according to the calculated laundry load C1 from the memory table (step 12), and the valve control circuit (83) receives the water injection valve (52). Is commanded and water is injected (step 13).
When the predetermined amount of water injection is completed, the valve (52) is closed, and the dynamic load of the laundry is detected as in step 6 (step 14). By this step, the dynamic load C1 ′ of the dry laundry is calculated, and the amount of water injected according to the weight C1 ′ is determined by the memory table (step 15).
Since the weight C1 ′ of the laundry in the dry state is lighter than the weight C1 measured in Step 11 (C1 ′ <C1), unnecessary water is drained (Step 16). In addition, when the laundry is added after the water injection in step 13 and C1 ′> C1, the water injection is performed.
[0035]
After the water injection is completed, the washing process is executed in the same manner as in Example 1 (Step 17). The detection of the dynamic load in the washing process is the same as in Step 6.
If the dynamic load C2 of the laundry obtained in step 18 is larger than the dynamic load C1 ′, it is determined that the laundry has been additionally charged after water injection (Yes in step 19), and the memory is stored again. Water injection is performed by opening the water injection valve (52) so that the amount of water injection corresponds to the dynamic load C2 stored in the table.
On the contrary, when the dynamic load C2 is equal to or less than the dynamic load C1 ′, the rinsing process is started (No in Step 19, Step 20). If the dynamic load C2 is smaller than the dynamic load C1 ′, the process may return to step 12 and be replaced with water injection to drain the unnecessary amount.
[0036]
In Example 2, the description of the rinsing step and the dehydrating step is omitted, but it is desirable that the amount of water is similarly adjusted by measuring the dynamic load of the laundry in the rinsing step.
[0037]
The above description of the embodiments is for explaining the present invention, and should not be construed as limiting the invention described in the claims or reducing the scope thereof. Moreover, each part structure of this invention is not restricted to the said Example, A various deformation | transformation is possible within the technical scope as described in a claim.
[0038]
For example, in the above embodiment, the weight of the laundry is measured before the washing step. However, the weight may be measured in the washing step, the rinsing step, or the like as long as the water is poured. Further, the configuration of the washing machine (10) is not limited to the above embodiment.
[0039]
【The invention's effect】
According to the washing machine of the present invention, it is possible to measure the weight of the laundry in the washing tub after pouring water, so even if additional laundry is taken in or taken out after the start of washing, depending on the added amount or taken out amount. The amount of water can be adjusted. Therefore, it is possible to perform easy washing with an amount of water corresponding to the weight of the laundry, and it is possible to achieve an improvement in cleaning power, optimization of the time required for washing, and water saving without leaving too much or no washing.
Furthermore, even if the wet laundry is thrown in, washing can be performed based on the weight of the laundry in the washing tub after pouring, so that extra water pouring is performed as in the past. Absent.
In addition, since the total weight of the laundry and the water injection amount can be measured with the load detector, there is no need to separately provide a water amount sensor or the like for measuring the water injection amount.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a washing machine of the present invention.
FIG. 2 is a block diagram showing an electrical system of the washing machine of the present invention.
FIG. 3 is a graph showing the relationship between the voltage change of the load detector and the elapsed time when only water is put in the washing tub and rotated.
FIG. 4 is a graph showing the relationship between the voltage change of the load detector and the elapsed time when water and laundry are put in a washing tub and rotated.
FIG. 5 is a graph showing the relationship between the voltage change of the load detector and the elapsed time when water and laundry are put in a washing tub and rotated.
FIG. 6 is a graph showing the relationship between the voltage change of the load detector and the elapsed time when water and laundry are put in a washing tub and rotated.
FIG. 7 is a graph showing the relationship between the voltage change of the load detector and the elapsed time when water and laundry are put in the washing tub and rotated.
FIG. 8 is a graph (extract) showing the secondary vibration amplitude of FIG. 3;
FIG. 9 is a graph (extract) showing the secondary vibration amplitude of FIG. 4;
10 is a graph (extract) showing the secondary vibration amplitude of FIG. 5. FIG.
11 is a graph (extract) showing the secondary vibration amplitude of FIG. 6;
12 is a graph (extract) showing the secondary vibration amplitude of FIG. 7; FIG.
FIG. 13 is a graph showing the relationship between the weight of the laundry and the total time exceeding the threshold amplitude.
FIG. 14 is a graph showing the relationship between the weight of laundry and the total time exceeding the threshold amplitude.
15 is a flowchart of Example 1. FIG.
FIG. 16 is a flowchart of the second embodiment.
[Explanation of symbols]
(10) Washing machine
(20) Washing tub
(22) Inner tank
(24) Outer tank
(30) Hanging rod
(70) Load detector

Claims (4)

A method for detecting the weight of laundry in a washing machine in which a laundry tub is composed of an inner tub that is loaded with laundry and stirred by a pulsator and an outer tub that rotatably supports the inner tub. There,
Measuring the static load D1 of the laundry tub into which the laundry has been loaded, and detecting the static load C1 of the loaded laundry;
Pouring water into the washing tub;
Detecting a dynamic load D2 of a laundry tub containing laundry and water while rotating the inner tub and / or pulsator, and a time-series change waveform of the dynamic load D2.
A high-frequency component is extracted from the obtained change waveform of the dynamic load D2 to obtain a secondary vibration waveform, which is present in the laundry tub based on the dynamic load D2 and the secondary vibration waveform of the laundry tub including laundry and water. Determining a laundry load C2;
A laundry weight detection method for a washing machine, comprising: The laundry load detection method according to claim 1, wherein the laundry dynamic load C2 is determined based on a dynamic load D2 of a laundry tub including laundry and water and an amplitude of a secondary vibration waveform. The laundry dynamic load C2 is determined based on a dynamic load D2 of a laundry tub including laundry and water and a total time when the amplitude of the secondary vibration waveform exceeds a predetermined threshold. The laundry weight detection method. A method for controlling a washing machine in which a washing tub comprising an inner tub that is loaded with laundry and stirred by a pulsator and an outer tub that rotatably supports the inner tub is housed in a washing machine housing,
Measuring the static load D1 of the laundry tub into which the laundry has been loaded, and detecting the static load C1 of the loaded laundry;
Pouring water into the washing tub;
Detecting a dynamic load D2 of a laundry tub containing laundry and water while rotating the inner tub and / or pulsator, and a time-series change waveform of the dynamic load D2.
A high-frequency component is extracted from the obtained change waveform of the dynamic load D2 to obtain a secondary vibration waveform, which is present in the laundry tub based on the dynamic load D2 and the secondary vibration waveform of the laundry tub including laundry and water. Determining a laundry load C2;
Comparing the determined dynamic load C2 of the laundry with the static load C1 of the laundry measured before pouring, and adjusting the amount of water in the washing tub according to the difference;
A method for controlling a washing machine, comprising:

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