JPH048395A - Cloth amount detecting system for washing machine - Google Patents

Abstract

PURPOSE:To make high accurate detection possible of a laundry amount in no relation to a power supply frequency by applying a plurality of pulse widths, different from each other by the power supply frequency, to a riseup width between pulses in one period of capacitor terminal voltage. CONSTITUTION:Counter electromotive force of an induction motor, when a rotary unit is rotated by inertia at off-time, is detected by terminal voltage of a motor driving capacitor and converted into a DC square wave pulse, and a cloth amount is decided by measuring widths t1, t2 of riseup time between these pulses. In the width of the riseup time between the pulses, in the case of a frequency 50Hz, the pulse t1 of the riseup time between the first and third pulses (a), (b) is measured because the fourth pulse (d) is difficult to be output, and in the case of a frequency 60Hz, the width t2 of the riseup time between the second and fourth pulses (c), (d) is measured because of no difference of the width of the riseup time between the pulses with the width t2 of the riseup time of the pulse in a short frequency. In both power supply frequencies, a laundry amount is determined by comparing with the laundry amount, in which total time of repeating this frequency 20 times is previously stored in a microcomputer, with a relation of the time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a washing machine equipped with a cloth amount detection device, and particularly to a washing machine equipped with a 50H washing machine.
The present invention relates to a washing machine that can detect the amount of cloth with high precision at both 60Hz and 60Hz frequencies.

[Conventional technology]

Conventional devices are disclosed in Japanese Patent Application Laid-Open Nos. 61-3096 and 1996-1.
As described in No. 19290 and Japanese Unexamined Patent Publication No. 1-185289, after a constant supply of water, the rotary blade is rotated and stirred, and then turned off.
When the rotor blade rotates due to inertia, the back electromotive force of the motor is detected by the terminal voltage of the motor drive capacitor, and this is converted into DC square wave pulses. By counting the number of pulses, the amount of cloth can be calculated. It was to be judged.

In addition, there is a method that detects the amount of cloth by measuring the width of time between pulses at the same location regardless of the power frequency (50 Hz, 60 Hz) without counting the number of pulses.

[Problem to be solved by the invention]

The above-mentioned conventional technology does not take into account the accuracy of measuring the amount of cloth depending on the power supply frequency, and has a problem in that the accuracy of measuring the amount of cloth varies depending on the power frequency.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for detecting the amount of laundry in a washing machine that can detect the amount of laundry with high accuracy regardless of the power frequency in order to solve the above-mentioned problems.

[Means to solve the problem]

In order to achieve the above objective, a plurality of different pulse widths are applied to the rise width between pulses in one cycle of the capacitor terminal voltage depending on the power supply frequency6. For example, at 50 Hz, the pulse width is 1 to 3, and at 60 Hz, the width is 2 pulses. Note: As shown in the fourth shot, the measurement method was changed depending on the power frequency.

[Effect]

The measured value when detecting the amount of cloth by applying the rise width between pulses at the same location regardless of the power frequency is as follows:
For example, the width of the rise time between 60Hz pulses is 50H.
Compared to z, there is less difference and it is difficult to measure, resulting in lower accuracy in detecting the amount of cloth. On the other hand, the measurement value when the cloth amount detection operation is performed by applying pulses used at multiple locations depending on the power supply frequency is that the width of the rise time between pulses at 60 Hz is the same as that at 50 Hz (the time between pulses is the same as that at 50 Hz). (with a clear width), which allows the washing machine to accurately detect the amount of cloth at a frequency of 60 Hz.

〔Example〕

An embodiment of the present invention will be described based on the drawings.

As shown in FIG. 1, a washing machine employing an embodiment of the present invention has an outer tub made of synthetic resin in an outer frame 1 made of a steel plate, which is equipped with a suspension rack 2 and a vibration isolating device 3 made of elastic rubber of a coil spring. Four hanging rods 2 and four vibration isolators 3 are provided to hang the four hanging rods 2 and vibration isolators 3.

A washing/drying tank 5 made of synthetic resin is rotatably provided in an outer tank 4 that stores water for washing. The washing and dehydrating tank 5 is provided with a large number of dehydrating holes 5a, and a rotating body 6 consisting of a pulse sweater or an agitator is rotatably provided at the center bottom. During washing and rinsing operations, the washing and dehydrating tank 5 is kept stationary and rotated. Rotate the body 6 clockwise and counterclockwise.

In addition, during spin-driving operation, a rotating body 6 rotates the washing and dehydration tank in one direction, and a drive device 7 rotates the washing and dehydration tank.
It is carried out by

The drive device 7 connects a motor 8 and the rotation of the motor 8 to a rotating body 6.
Alternatively, a transmission means 9 consisting of a pulley 9a and a belt 9b for transmitting data to the washing and dehydrating tank 5, and a clutch device that rotates only the rotating body 6 during washing and rinsing, or rotates the washing and dehydrating tank 5 during dehydration. 1i10, a solenoid 7a that performs the switching, and a drainage device 12 that controls drainage.

The drive device 7 is fixed to the bottom surface of the outer tank 4 using a support plate 15 made of a steel plate. The outer tank 4 is provided with an inlet 4C to which a P, S tube 27 for transmitting the pressure of water in the outer tank 4 to a water level sensor 26 is connected.

A top canopy 19 made of synthetic resin is provided at the upper part of the outer frame and has an input port 19a for loading laundry and an operation box 19b for storing electrical components such as a controller. A lid 20 made of synthetic resin is provided on the inlet 19a.

An operation panel 21 is attached to the upper surface of the operation box 19b, and a water supply solenoid valve 24 is provided inside the operation box 19b.

A water level sensor 26 disposed in the operation box 19b detects the pressure of water in the outer tank 4 to determine whether the water has accumulated to a specified water level. The water level sensor 26 includes a core,
It consists of coils, springs, etc.

A controller unit that controls washing, rinsing, dehydration, etc. is arranged inside the storage box 31.

A power switch button 29 and an external operation switch 30 are arranged on the operation panel 21.

FIG. 2 shows the operation panel 21. As shown in FIG.

In the above configuration, when the power switch button 29 is pressed to turn the power switch ONL, and the "Sensor (marker 1) J" button of the external operation switch 30 is pressed, the water supply solenoid valve 24 is energized by a signal from the controller. At this time, the solenoid 7a is also energized to enter the dewatering state, and the motor is energized for 0.5 seconds ON and 4 seconds OFF, and the washing and dehydration tub rotates in one direction with a gentle rotation to remove the laundry. I try to make sure that the water from the water supply is evenly spread over the area.

When the water level sensor detects water supply up to the lowest water level, the water supply solenoid valve 24. Stop energizing solenoid 7a,
The motor 8 is energized and stirred.

At this time, the clutch device 10 is in a dehydrated state, so
In order to ensure that the clutch device 10 is in the washing state and not to damage the cloth, the reverse stirring water flow is stronger than cloth amount detection stirring and weaker than normal stirring for 0.5 seconds ON - 0.5 seconds 0FF After operating for 8 seconds, cloth amount detection stirring is carried out. Do this.

In the cloth amount detection process, reverse stirring is performed for 0.4 seconds ON and 1 second OFF, and the back electromotive force of the condenser run induction motor when the rotating body 6 rotates due to inertia when it is OFF is transferred to the capacitor 8a for driving the motor 8. The amount of cloth is determined by detecting the terminal voltage, converting it into a DC rectangular wave pulse, and measuring the width t, t2 of the rise time between the pulses. In other words, when there is a large amount of laundry, the resistance to the rotating body 6 is large, which prevents inertia rotation and reduces the width tz of the rise time between pulses.
+tz becomes long, and when the amount of laundry is small, conversely, the width t, t2 of the rise time between pulses becomes short.

Also, the width of the rise time between pulses varies depending on the power supply frequency, and in the case of a frequency of 50Hz, the width of the rise time between pulses (
■) is difficult to appear, so we measured the width t1 of the rise time of the first pulse (■) and the third pulse (@) of the dual-wave detection pulse detected by the circuit shown in Figure 3. In the case of 60Hz, the pulse rise time width t2 has a short frequency and there is no difference in the rise time width between pulses, so the rise time of the second pulse (0) and the fourth pulse (■) is Measure the width t2 of. The total time of repeating this 20 times for both power supply frequencies was compared with the relationship between the amount of washing and time stored in the microcomputer in advance.

Determine the amount of laundry to be done, and adjust the water level and washing time according to the amount of laundry.

This automatically sets the dehydration time and other parameters for subsequent operations.

According to this embodiment, full-wave pulse detection is performed and the rise time of the first and third pulses or the second and fourth pulses is measured, so it is used in the pulse conversion circuit. Pulse width variations due to variations in Zener diodes (■), photocouplers, etc. can be minimized.

Another example is the pulse time tz when detecting the amount of cloth.

The microcomputer stores the total measurement time of the clockwise and counterclockwise rotations of the rotating body 6 to measure tz, and if both values are greater than or equal to a value predetermined by the microcomputer, the values are summed and the measured value is calculated. If the value is below a predetermined value, safety can be ensured by indicating an abnormality with a blinking buzzer and lamp.

Further, in the case of 60 Hz, there is no difference in the rise time width t2, so other combinations can be applied. For example, change the measurement points such as the width ta of the rise time of the 3rd shot (@) and the 5th shot ([F]), the width tb of the rise time of the 4th shot (○) and the 6th shot (■), etc. It is possible to detect the amount of cloth with high accuracy.

In addition, for stirring to detect the amount of cloth, the rotary blade rotates clockwise ON-O.
FF or counterclockwise rotation ON - 〇FF The back electromotive force of the motor when the rotor rotates by inertia during stirring is detected as the terminal voltage of the capacitor, and this is converted into a DC rectangular wave pulse. A similar effect can be obtained by measuring time and detecting the amount of cloth.

〔Effect of the invention〕

According to the present invention, by changing the width of the rise time between measured pulses depending on the power supply frequency, 50Hz, 60Hz,
Both Hz and Hz have the effect of making it possible to detect the amount of cloth with very high accuracy.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a fully automatic washing machine, FIG. 2 is a circuit diagram of an embodiment of the laundry amount implementation, and FIG. 3 is a diagram of generated pulses detected in FIG. 1... Outer frame, 2... Hanging rod, 3... Vibration isolator, 4
... Outer tank, 5. Washing/dehydration tank, 6... Rotating body, 7
...Drive device. 8... Motor, 9... Transmission means, 1o... Clutch device, 12... Drainage device, 15... Support plate, 19
...Top cover, 21...Operation panel, 24...
・Water supply solenoid valve, 26...Water level sensor, 29...Power switch button, 30th

Claims (1)

[Claims] 1. After a constant supply of water, the rotor blades are operated in one direction from ON to OFF, or stirred in the right and left directions from ON to OFF, and the back electromotive force of the condenser run induction motor when the rotor blades rotate by inertia when OFF. In a washing machine equipped with a cloth amount detection device that detects the amount of cloth using the terminal voltage of the motor drive capacitor, converts it into a DC rectangular wave pulse, and measures this time to determine the amount of cloth, the condenser run induction motor is turned OFF. A method for detecting the amount of cloth in a washing machine, characterized in that the amount of cloth is detected by measuring the rise width between pulses of a motor terminal voltage that sometimes attenuates at different points at a power frequency of 50 Hz and 60 Hz.