JPS62117587A - Over-vibration preventing apparatus of full-automatic washing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an over-vibration prevention device that prevents over-vibration during the dewatering process of a fully automatic washing machine, and particularly to a means for predicting the occurrence of over-vibration and taking measures in advance. Regarding.

[Conventional technology]

In a fully automatic washing machine, when performing a spin-drying process, if the unbalance of the laundry is large, the spin-drying basket becomes over-vibrated. Conventionally, as an over-vibration prevention means for preventing such over-vibration, the over-vibration that actually occurs when the dehydration basket is rotated is disclosed in, for example, Japanese Utility Model Application No. 60-30788. A method has been adopted in which detection is performed using a limit switch such as a mechanical vibration switch, and the dehydration basket is temporarily stopped based on the detection signal and then rotated again.

[Problem to be Solved by the Invention J] In the conventional means described above, the limit switch does not work unless the rotation of the dehydration basket has increased considerably, that is, the resonance point has been reached and the amplitude of t has become sufficiently large. Therefore, after the limit switch detects excessive vibration, it takes a relatively long time to stop the rotation of the dehydration basket and then restart the dehydration process from the beginning. The loss was large.

Therefore, the present invention makes it possible to predict the occurrence of over-vibration due to unbalanced laundry in the balancing process before entering the dehydration process, and to quickly eliminate the unbalanced state before over-vibration actually occurs. The purpose of the present invention is to provide an over-vibration prevention device for a fully automatic washing machine that enables efficient dewatering in a short amount of time.

[Means for solving problems]

In order to solve the above problems and achieve the objects, the present invention is characterized by taking the following measures.

(1) A current detector is provided to detect the current value supplied to the drive motor of the fully automatic washing machine.

(2) Dehydration of the current value detected by this current detector] - A means is provided for sampling at a predetermined period during the balancing step which was performed just before.

(:3) A means for determining the difference between the maximum value and the minimum value of the current values sampled by this means is provided.

(4) A means is provided for comparing the difference obtained by this means with a preset reference value.

(5) A means is provided for repeating the above-mentioned balance/geo process when the result of the comparison by the comparison means is that the difference by one front tone is greater than the standard value.

[Effect]

By taking the above measures, the following effects occur. When the laundry is unbalanced, the ripple width of the current supplied to the drive motor becomes larger even in the initial rotation state than when the laundry is unbalanced. Therefore, by determining the difference between the maximum and minimum current values sampled during the initial state of rotation, that is, the balancing process, and comparing that difference with a preset reference value, it is possible to prevent overvibration from actually occurring. At the point in time, the occurrence of overvibration can be accurately predicted.

If over-vibration is predicted to occur, we immediately perform the balancing process again.
The unbalanced state will be promptly resolved.

〔Example〕

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a commercial AC power supply, and AC power is supplied from this power supply 1 to a drive motor 4 via a switch 2 and a sequence control circuit 3. As is well known, the sequence control circuit 3 controls the sequence so that each process such as pre-washing, washing, rinsing, draining, etc., balancing process, dehydration process, etc. is executed at a predetermined timing. It is something.

A current detector 5 for outputting the current supplied to the drive motor 4 is attached to the drive motor 4. The current detector 5 is composed of, for example, a current transformer.゛・, whose output is given to the sampling circuit 6 1,
The sampling circuit 6 starts a sampling operation in response to a sampling start signal S1 from the sequence control circuit 3, and receives a sampling end signal S2 from the sequence control circuit 3.
This ends the sampling operation.

The current value sampled by the sampling circuit 6 is supplied to the memory 7. This memory 7 is, for example, an RA
M, etc., and temporarily stores a sampling current value having a current value viscosity of about 0.1 ampere. The sampling current value stored in the memory 7 is read out to the arithmetic unit 8 when the sampling end signal S2 is sent from the sequence control circuit 3. The arithmetic unit 8 calculates the difference A between the maximum value and the minimum value of the read sampling current value. The difference A calculated by the calculator 8 becomes one input of the comparator 9. C is the other manual power of the comparator 9, and C is the reference value setter 10.
A preset reference value B is given by . Comparator 9
compares the power of two people, and if the difference A is larger than the reference value B, it is determined that an over-vibration has occurred, and an over-vibration prediction signal C is output. This over-vibration prediction signal C is given to the balancing repetition command unit 11. When this command device 11 is given the L over-vibration measurement signal C, it gives a command to the sequence control circuit 3 to repeat the balancing process. Note that the output signal of the comparator 9 is sent to the counter 12.
Also supplied. This counter 12 counts the number of times the output signal C is sent from the comparator 9. For example, when the output signal C is sent out repeatedly five times or more in a row, it shuts off the switch 2 and manually controls the unbalanced state of the laundry. This is to give you an opportunity to make corrections. Note that in FIG. 1, the portion surrounded by a broken line is composed of a microcomputer or the like.

Next, the operation of the apparatus configured as described above will be explained with reference to FIG. 2 and subsequent figures. As shown in FIG. 2, when the switch 2 is turned on at time t1, AC power from the power source 1 is supplied to the drive motor 4 via the sequence control circuit 3. Therefore, the motor 4 rotates and the washing process is started. When the washing process ends at time t2, the sequence control circuit 3 performs drainage and then shifts to the balancing process. In this balancing step, the dewatering basket rotates at a low speed of about 1 revolution per second so that the laundry is balanced within the dehydrating basket. Assume that the laundry is unbalanced and the current I supplied to the drive motor 4 is pulsating as shown in FIG. This current value I is detected by a current detector 5 and supplied to a sampling circuit 6. When a certain point t3 is reached just before the end of the balancing process, the sequence control circuit 3 sends sampling start signals S1 (to the sampling circuit 6).Then, the sampling circuit 6 performs sampling with a width of 25m5 at the time as shown in FIG. t
4 for about 2 seconds. This sampling current value is sequentially stored in the memory 7. When the sampling end signal s2 is sent from the sequence control circuit 3 at time t4, the above-mentioned sampling operation ends. At the same time, the sampling current value 71i stored in the memory 7 is read into the computing unit 8, and as shown in FIG. A is calculated. This difference A is compared with a reference value B in a comparator 9, and if A>B, an overvibration prediction signal C is output. Then, balancing repeat command 1
A balancing repetition command signal is applied from 1 to the sequence control circuit 3. As a result, the balancing process is executed again from the beginning. Normally, the unbalanced laundry is resolved after the above-described balancing process is repeated two or three times.

By eliminating the imbalance, the ripple in the current value supplied to the drive motor 4 becomes smaller, and when the relationship between the difference A and the reference value B becomes A<B, the overvibration prediction signal C from the comparator 9 is output.
is not sent. Therefore, the repeated command signal from the command unit 11 is not output as shown by the X mark in FIG. In this manner, the sequence control circuit 3 moves to the next step, the dehydration step. However, for some reason, the imbalance may not be resolved. Therefore, in this embodiment, when the output signal from the comparator 9 is repeatedly sent out about 5 times, the counter 12 detects it.
The counter output prohibits the operation of the balancing repeat command unit 11, and at the same time, the switch 2 is cut off. In this case, it is sufficient to remove the cause of the imbalance by manual operation and then restart the engine.

FIG. 4 is a diagram showing the rotation state of the dehydration basket in the above operation. As shown in FIG. 4, in this embodiment, when the occurrence of overvibration due to unbalanced laundry is predicted, the rotation speed starts to decrease from time point [4], and at the end of the first balancing process, time t5. At the time t immediately after
At 6, the balancing process is started again from the beginning. Therefore, the time required to perform a repeated operation is T1
That's fine.

On the other hand, in the conventional system, the limit switch is activated only when the rotation of the dehydration basket increases considerably, for example at time t7. Moreover, it takes a long time for the rotation speed of the dehydration basket to return to zero. Therefore, the time required to perform a repetitive operation is much larger than T1.
2, resulting in a huge loss of time. In this way, according to this embodiment, the unbalanced state is quickly resolved.

Note that the present invention is not limited to the above embodiment,
Of course, various modifications can be made without departing from the spirit of the invention.

〔Effect of the invention〕

According to the present invention, when the ripple width of the drive motor supply current is larger than the normal case in the crushing process before starting the dehydration process, excessive vibration due to unbalance of the laundry can be suppressed. 'The system is configured so that the balancing process L is immediately restarted from the beginning before C1 over-vibration actually occurs, so the unbalanced state is quickly resolved and the entire process is completed to enable efficient dewatering in a short period of time. It is possible to provide an over-vibration prevention device for automatic washing machines.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a diagram showing the operation timing of the embodiment, and FIG. 3 is a diagram showing means for detecting the current ripple width of the embodiment. Fourth
The figure is an explanatory diagram of the operation of the same embodiment. DESCRIPTION OF SYMBOLS 1...Commercial AC power supply, 2...Switch, 3...Sequence control circuit, 4...Drive motor, 5...Current detector, 6...Sampling circuit, 7...Memory , 8
...Arithmetic unit, 9...Comparator, 10...Reference value setter, 11...Balancing repetition [2 command unit, 12...
counter. Figure 1 Figure 2

Claims (1)

[Claims] a current detector for detecting a current value supplied to a drive motor of a fully automatic washing machine; a means for sampling the current value detected by the current detector over a predetermined period during a balancing process before a dehydration process; means for determining the difference between the maximum and minimum current values sampled by this means; means for comparing the difference determined by this means with a preset reference value; 1. An over-vibration prevention device for a fully automatic washing machine, comprising means for repeating the balancing process when the balance is larger than a reference value.