JP2011206137A - Washing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size of a substrate by coping with a plurality of electrodes having a plurality of functions by one detection means and reducing the number of components.SOLUTION: The washing machine includes: electrodes 8, 9 for bubble water detection; capacitors 35, 36 in which electrodes 17a, 17b for detecting the electric conductivity of washing liquid are connected to the secondary coil of magnetic coupling means 33, and which are connected in parallel with the primary coil of the magnetic coupling means 33; high frequency generation means for resonating the capacitor connected in parallel with the primary coil of the magnetic coupling means 33 in parallel at a high frequency which is twice or more the driving frequency of a motor 4; and a parallel resonance impedance measurement means connected to the output of the high frequency generation means, for measuring impedance during parallel resonance. Control means 11 includes bubble water detection sequence means 27 and a washing liquid electric conductivity detection sequence means 28, detects bubble water and the electric conductivity of the washing liquid by the respective electrodes and changes a washing control sequence.

Description

  The present invention relates to a washing machine that controls a washing operation optimal for laundry.

  Conventionally, it has been considered that this type of washing machine controls bubbles by detecting foam (for example, see Patent Document 1). FIG. 11 shows a configuration of a conventional washing machine described in Patent Document 1. In FIG. As shown in FIG. 11, the washing machine outer frame 51 elastically supports a water receiving tank 52, and a washing and dehydrating tank 53 is rotatably provided inside the water receiving tank 52. A pair of electrodes 55 is provided above the top surface opening 54 of the water receiving tank 52. The motor 56 drives the washing / dehydrating tub 53 during washing or dehydration.

  In the magnetic coupling circuit 57, the AC signal source 59 is connected to the primary coil 57a via the resistor 58, and the first rectifying / smoothing circuit 60 is connected. In the first rectifying and smoothing circuit 60, a diode 60a and a capacitor 60b are connected in series to both ends of the primary coil 57a.

  The second rectifying / smoothing circuit 61 is connected to the secondary coil 57 b of the magnetic coupling circuit 57. The second rectifying / smoothing circuit 61 has a configuration in which a diode 61a and a capacitor 61b are connected to both ends of the secondary coil 57b. Thereby, the alternating current generated in the primary coil 57a is converted into a direct current power source. The signal source is a rectangular wave, but any other alternating signal can be implemented.

  The current consumption circuit 62 is constituted by a transistor, and a collector and an emitter are connected to both ends of a capacitor 61b constituting a DC power source. The comparator 63 has a first resistor 64 and a second resistor 65 connected to its non-inverting input, and a third resistor 66 and a fourth resistor 67 connected to its inverting input.

  The other ends of the first resistor 64 and the third resistor 66 are connected to the plus terminal of the capacitor 61b, and the other ends of the second resistor 65 and the fourth resistor 67 are connected to the minus terminal of the capacitor 61b. Yes. The pair of electrodes 55 are connected to both ends of the fourth resistor 67.

  The first resistor 64, the second resistor 65, and the third resistor 66 have the same resistance value, and the fourth resistor 67 has a larger value. Therefore, in a state where no bubbles touch between the pair of electrodes 55, the non-inverting input voltage is lower than the inverting input voltage, and the output of the comparator 63 is a low voltage. The microcomputer 68 inputs a DC voltage obtained from the capacitor 60 b of the first rectifying and smoothing circuit 60, and controls the motor 56 from the output of the microcomputer 68 according to the value.

  The operation in the above configuration will be described. According to the washing control program built in the microcomputer 68, when the motor 56 repeats normal rotation and reversal with a certain pause time and washing is performed, bubbles gradually increase and touch the pair of electrodes 55. The voltage obtained by dividing the voltage of the capacitor 61 b by the resistance division of the fourth resistor 67, the parallel resistance of the bubble equivalent resistance, and the third resistor 66 is applied to the inverting input of the comparator 63. On the other hand, the intermediate voltage of the capacitor 61b is applied to the non-inverting input.

  When a certain amount of bubbles touch the pair of electrodes 55, the voltage of the inverting input is lowered from the non-inverting input voltage, and the output of the comparator 63 becomes high. As a result, the current consumption circuit 62 is turned on and consumes current from the capacitor 61b which is a DC power supply. As a result, the voltage of the capacitor 60b, which is the output voltage of the first rectifying / smoothing circuit 60 connected to the primary coil 57a, decreases.

  The microcomputer 68 detects the reduced voltage and recognizes the generation of bubbles, and shifts the control such as the number of rotations of the motor 56, the rotation time, and the rest time to the control that reduces the bubbles step by step. If it disappears, it will become a little stronger, and it will increase and decrease, and shift to optimal washing control. Thus, washing control can be performed in a state where the maximum washing performance before the foam overflows can be obtained.

JP 2001-293287 A

  However, in the conventional configuration, there is a foam water detection electrode for detecting foam and water, and there is a foam water detection means corresponding thereto, a washing liquid conductivity detection electrode for detecting the conductivity of the washing liquid, and There was a corresponding washing liquid conductivity detection means. As described above, since a plurality of detection means corresponding to electrodes having a plurality of functions are provided, there is a problem that the number of parts is large and the size of the board on which these detection means are mounted is increased.

  The present invention solves the above-described conventional problems, and includes a plurality of electrodes for washing liquid conductivity detection for detecting the conductivity of the washing liquid, and a plurality of electrodes for foam water detection for detecting foam and water. Accordingly, it is an object of the present invention to provide a washing machine having a small number of parts and a reduced substrate size by using a single detection means.

  In order to solve the above-described conventional problems, a washing machine of the present invention has a drum that houses laundry, an outer tub that rotatably includes the drum, a motor that rotationally drives the drum, and an insulating structure. Magnetic coupling means, a pair of electrodes for detecting foam water disposed in the outer tub, a pair of electrodes for detecting the conductivity of the washing liquid, the electrode for detecting the foam water and the conductivity detection of the washing liquid And a capacitor connected in parallel with the primary coil of the magnetic coupling means, and a capacitor connected in parallel with the primary coil of the magnetic coupling means. A high-frequency generating means for parallel resonance at a high frequency that is at least twice the driving frequency, a parallel resonant impedance measuring means connected to the output of the high-frequency generating means for measuring impedance at the time of parallel resonance, washing, rinsing, removing Control means for sequentially controlling each of the steps, the control means has a foam water detection sequence means for detecting foam and water, and a washing liquid conductivity detection sequence means for detecting the conductivity of the washing liquid, The electric conductivity of the foam water and the washing liquid is detected by each electrode, and the washing control sequence is changed.

  Thus, it is possible to cope with a plurality of electrodes for detecting the conductivity of the washing liquid for detecting the conductivity of the washing liquid and the electrode for detecting the foamed water for detecting foam and water with one detection means. The number of components is small, and the size of the board can be reduced. Further, the control means has a foam water detection sequence means for detecting foam and water, and recognizes that the foam or water is detected, and then the parallel resonance impedance by the change generated in the primary coil of the magnetic coupling means. By looking at the output of the measuring means, it is possible to clearly recognize whether it is foam or water. In addition, the control means has a washing liquid conductivity detection sequence means for detecting the conductivity of the washing liquid, and recognizes that the electric conductivity of the washing liquid is detected. Since the output of the parallel resonance impedance measuring means is seen by the change that occurs, the conductivity of the washing liquid can be clearly recognized.

  The washing machine of the present invention can correspond to a plurality of electrodes having a plurality of functions such as an electrode for detecting the conductivity of the washing liquid and an electrode for detecting foam and water with one detection means, The number of components is small, and the size of the board can be reduced.

Configuration diagram of washing machine according to Embodiment 1 of the present invention Cross-sectional view of washing liquid sensor of the washing machine Internal block diagram of control means of the washing machine Circuit diagram of foam water washing liquid conductivity detection means of the washing machine Relationship diagram between resistance value of electrode and amount of foam of the washing machine Frequency and impedance characteristic diagram of parallel resonance impedance of the washing machine Output voltage waveform chart of foam water washing liquid conductivity detection means of the washing machine Characteristic diagram of foam resistance of the washing machine and output voltage of foam water washing liquid conductivity detection means Characteristic diagram of sweat component amount and resistance value contained in washing liquid of the washing machine Characteristic diagram of Z1 and Z2 according to the turns ratio of the insulation transformer of the washing machine Configuration diagram of a conventional washing machine

  1st invention arrange | positions in the said outer tub with the drum which accommodates the laundry, the outer tub which included the said drum rotatably, the motor which rotationally drives the said drum, the magnetic coupling means with insulation structure A pair of electrodes for detecting the foamed water, a pair of electrodes for detecting the conductivity of the washing liquid, the electrode for detecting the foamed water, and the electrode for detecting the conductivity of the washing liquid. A capacitor connected to the coil and connected in parallel with the primary coil of the magnetic coupling means and a capacitor connected in parallel with the primary coil of the magnetic coupling means are parallel-resonated at a frequency higher than twice the driving frequency of the motor. High-frequency generating means, parallel resonant impedance measuring means connected to the output of the high-frequency generating means for measuring impedance at the time of parallel resonance, and control means for sequentially controlling each step of washing, rinsing and dehydration The control means includes foam water detection sequence means for detecting foam and water, and washing liquid conductivity detection sequence means for detecting the conductivity of the washing liquid. The washing control sequence is changed by detecting with an electrode.

  Since the electrode for detecting foamed water and the electrode for detecting the conductivity of the washing liquid are connected to the secondary coil of the magnetic coupling means, the change in the primary coil of the magnetic coupling means directly causes the change in the parallel resonance impedance measuring means. Looking at the output, I don't know if bubbles or water contacted, or if the conductivity of the washing liquid changed. Therefore, the control means recognizes that the foam or water is detected by providing the foam water detection sequence means for detecting foam and water in the washing sequence, and then the primary coil of the magnetic coupling means. Since the output of the parallel resonance impedance measuring means is seen by the change that occurs in this, it is possible to clearly recognize whether it is foam or water.

  In addition, the control means recognizes that the conductivity of the washing liquid is detected by providing the washing liquid conductivity detection sequence means for detecting the electric conductivity of the washing liquid in the washing sequence. Since the output of the parallel resonance impedance measuring means is seen by the change occurring in the primary coil of the magnetic coupling means, the conductivity of the washing liquid can be clearly recognized.

  In this way, the control means detects the foam and water, so that the maximum washing performance before the foam always overflows even if the conditions of the detergent, the amount of water, the soiling condition of clothing and other factors of foam generation change. The laundry control can be performed in a state where In addition, since it takes a long time to wash laundry, it can recognize the electrical conductivity of the washing liquid, so that it can control the washing sequence according to the light dirt on the laundry. Thus, the washing time can be shortened.

  In the second aspect of the invention, in particular, the secondary coil of the insulation transformer of the first aspect of the invention can be made one secondary coil by increasing the number of turns by taking out one terminal with an intermediate number of turns. Can be reduced in size.

  According to a third aspect of the present invention, in particular, the secondary coil of the insulation transformer of the first aspect includes a washing liquid conductivity detection sequence means and a foam water detection sequence means, an electrode for detecting the conductivity of the washing liquid, and a foam water detection. Since the number of turns of the secondary coil is changed by providing the switching means for switching to the electrode for use, detection of bubbles and water and the conductivity of the washing liquid can be detected in the primary coil.

  In the fourth aspect of the invention, in particular, the resonance frequency of the first aspect of the invention is set to 30 kHz or more, so that the drive frequency of the motor can be doubled around 15 kHz, and malfunction due to noise from the motor is prevented. Can be prevented.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a schematic configuration diagram of a washing machine according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view of a washing liquid sensor of the washing machine, and FIG. 3 is an internal block diagram of control means of the washing machine. FIG. 4 is a circuit diagram of the foam water washing liquid conductivity detecting means of the washing machine.

  1 to 4, reference numeral 1 denotes an outer box of a washing machine main body, and an outer tub 2 is disposed therein, and a drum 3 serving as a washing tub is inclined inside the outer tub 2 so as to incline upward from the horizontal direction. It arrange | positions in the state which can be rotated by the axis | shaft. The drum 3 is rotated by rotation of a motor 4 connected to the back side. The drum 3 is provided with a plurality of water passage holes (not shown) on the outer peripheral surface, and functions as a washing tub, a dewatering tub, and a drying tub.

  A water intake 5 is provided at the lowest part of the outer tub 2, a drain valve 6 is provided downstream of the outer tub 2 and connected to a drain pipe 7. The drain valve 6 is opened and closed, and washing water in the outer tub 2 is discharged. . 8 is attached to the lower side on the back side of the outer tub 2 so as not to come into contact with the drum 3. With the electrode B for detecting foamed water, the electrode A8 and the electrode B9 constitute a pair of electrodes for detecting foamed water in the outer tub 2 and the drum 3.

  Electrode A8 and electrode B9 are connected to foam water washing liquid conductivity detecting means 10 for detecting the conductivity of foam and water in outer tub 2 and the washing liquid. Reference numeral 11 denotes a control means for controlling the motor 4 for rotating the drum 3. The output of the foamed water washing liquid conductivity detecting means 10 is connected to the input of the control means 11. 12 is water, 13 is foam generated by washing, and A is laundry.

  Between the intake port 5 and the drain valve 6, one end of a circulation path 15 connected to the discharge port 14 for discharging the washing liquid taken in from the intake port 5 into the drum 3 is connected, and the washing in the outer tub 2 is performed. The liquid and the rinsing liquid can be circulated by a circulation pump 16 provided in the circulation path 15. The circulation path 15 is provided with a washing liquid sensor 17 for detecting the state of the washing liquid.

  As shown in FIG. 2, the washing liquid sensor 17 is installed such that the electrode 17 a and the electrode b 17 b face each other with the circulation path 15 therebetween, and the tip portion comes into contact with the washing liquid and the rinsing liquid flowing through the circulation path 15. Is provided. The electrode 17a and the electrode 17b of the washing liquid sensor 17 are connected to the foamed washing liquid conductivity detecting means 10. The washing liquid sensor 17 is installed in a horizontal portion 15 a that extends toward the discharge port 14 of the circulation path 15.

  Next, the configuration of the control means 11 is shown in FIG. The power supply means 20 is connected to an AC power supply and supplies power to the central control means 21. The central control means 21 is connected to an operation display means 22 that receives an operation input of the washing machine, and is connected to a display board 23 that indicates the state of the washing machine. The central control means 21 is connected to a motor control means 24 that controls the motor 4 and a drain valve control means 25 that controls the drain valve 6.

  The central control means 21 is connected to the washing liquid sensor 17 and is connected to foam water washing liquid conductivity determining means 26 for detecting foam and water and detecting the electric conductivity of the washing liquid. The central control means 21 is connected to the foam water detection sequence means 27 for generating a sequence for detecting foam and water, and the washing liquid conductivity detection sequence means 28 for generating a sequence for detecting the conductivity of the washing liquid. Has been.

  Next, the configuration of the foamed water washing liquid conductivity detecting means 10 is shown in FIG. 8 is attached to the upper part of the outer tub 2 so as not to come into contact with the drum 3, and the foam water detection electrode A is attached to the lower part of the outer tub 2 so as not to come into contact with the drum 3 paired with the electrode A8. Electrodes B and 17a for detecting foamed water are electrodes a of the washing liquid sensor 17 immersed in the washing liquid for detecting the electric conductivity of the washing liquid, and 17b is a washing for detecting the electric conductivity of the washing liquid paired with the electrode a. This is an electrode of the washing liquid sensor 17 immersed in the liquid.

  33 is an insulating transformer as magnetic coupling means, 33c is one end of a secondary coil of the insulating transformer 33, 33d is an intermediate terminal of a secondary coil of the insulating transformer 33, and 33e is a secondary terminal of the insulating transformer 33. The other end of the coil. One end 33c of the secondary coil of the insulating transformer 33 is connected to the electrode A8 and the electrode 17a, the intermediate terminal 33d is connected to one end of the contact 46 of the relay 45, and the other end of the contact 46 is connected to the electrode 17b. The other end 33e of the secondary coil of the transformer 33 is connected to one end of the contact 43 of the relay 42, and the other end of the contact 43 is connected to the electrode B9.

  One end 33a of the primary coil of the insulating transformer 33 is connected to one end of a capacitor (C1) 35 connected in parallel with the primary coil of the insulating transformer 33 and an input of an inverter 37 which is an amplifier circuit. The other end 33b of the primary coil of the insulating transformer 33 is connected to one end of a capacitor (C2) 36 connected in parallel with the primary coil, the output of the inverter 37, and the anode of the diode (D1) 38.

  The other ends of the capacitor (C1) 35 and the capacitor (C2) 36 are connected to the ground. The cathode of the diode (D1) 38 is connected to one end of the capacitor (C3) 39, one end of the resistor (R1) 40, and the control means 11. The other ends of the capacitor (C3) 39 and the resistor (R1) 40 are connected to the ground.

  The voltage of the diode (D1) 38 is input to the foamed water washing liquid conductivity determining means 26 of the control means 11, and the output of the foamed water washing liquid conductivity determining means 26 is connected to the central control means 21. The Colpitts oscillation circuit realizes a high-frequency oscillation means by the configuration of the primary coil of the insulating transformer 33, the capacitor (C1) 35, and the capacitor (C2) 36 connected to the inverter 37 that is an amplifier circuit.

  The output of the washing liquid conductivity detection sequence means 28, which is the output of the control means 11, is connected to the input of the drive circuit 44 of the relay 45, and the output of the foamed water detection sequence means 27 is connected to the input of the drive means 41 of the relay 42. It is connected.

  Next, the operation | movement which detects the foam of the washing machine of this Embodiment is demonstrated. First, from the operation display means 22 of the control means 11 shown in FIG. Then, after a predetermined amount of washing water is supplied, the motor control means 24 operates to drive the motor 4 shown in FIG. 1 to rotate the drum 3.

  In the laundry A in the drum 3, dirt is melted from the laundry due to the agitation by the forward / reverse inversion operation of the drum 3 and the action of the detergent, and the washing water 12 gradually becomes cloudy and foam 13 is generated at the same time. The foam 13 exits from a large number of small holes (not shown) provided on the peripheral side wall surface of the drum 3 and enters the outer tub 2. The foam 13 that has entered the outer tub 2 first comes into contact with the electrode B9 attached below the outer tub 2, and when the amount of the foam 13 is increased, it comes into contact with the electrode A8 attached above the outer tub 2. A current flows through the bubbles 13 to the electrodes A8 and B9.

  On the other hand, the amount of the bubbles 13 can be captured as a change in resistance value between the electrode A8 and the electrode B9, and FIG. 5 shows the relationship between the amount of bubbles and the resistance value between the electrodes A8 and B9. If the resistance value between the electrode A8 and the electrode B9 is measured and the resistance is identified at 500 kΩ, it can be determined that there is no bubble if it is 500 kΩ or more and that there is a bubble if it is 500 kΩ or less.

  Next, a method for detecting the resistance value between the electrode A8 and the electrode B9 by the foamed water washing liquid conductivity detecting means 10 will be specifically described with reference to FIG. Now, since the voltage is output from the foam water detection sequence means 27 of the control means 11, the drive means 41 of the relay 42 of the foam water washing liquid conductivity detection means 10 is turned on, the relay 42 is turned on and the contact 43 is turned on. The foam water detection electrode B9 is connected to the secondary coil 33e of the insulation transformer 33, and the foam water detection electrode A8 is connected to the secondary coil 33c of the insulation transformer 33.

  At this time, there is no bubble 13 between the electrode A8 for detecting bubble water and the electrode B9, and when the resistance value between the secondary coil 33c and 33e when the air contacts is infinite, the primary coil The parallel resonance impedance is Z1 as shown in FIG. Assuming that the resistance value when the bubble 13 is in contact between the electrode A8 and the electrode B9 is Z2, the AC waveform oscillating by resonating at the frequency fr on the primary side has the same AC frequency fr voltage on the secondary side. appear. At that time, the parallel resonance impedance of the primary coil is Z12, which is smaller than Z1.

  That is, when the bubble 13 adheres to the electrode of the secondary coil and the resistance value decreases, the parallel resonance impedance Z of the primary coil also decreases. As a result, the amplitude of the sine wave of the capacitor (C2) 36, which is the output of the sine wave of the Colpitts oscillation circuit, also becomes small, and the reference potential of the inverter 37 is centered on the anode of the diode (D1) 38 as shown by the broken line in FIG. A sine wave is applied.

  The capacitor (C3) 39 connected to the anode of the diode (D1) 38 is set small so as not to affect the capacitor (C1) 35 and the capacitor (C2) 36, and is connected in parallel to the capacitor (C3) 39. If the resistance (R1) 40 is increased to increase the discharge time constant, the peak waveform of the sine wave is maintained in the cathode waveform of the diode (D1) 38, as shown by the solid line in FIG. This voltage becomes the input voltage of the foam water washing liquid conductivity determining means 26 of the control means 11.

  FIG. 8 shows the relationship between the resistance value between the electrodes A8 and B9 measured in advance and the output voltage of the parallel resonance impedance measuring means 41. In FIG. When the resistance value between the electrode A8 and the electrode B9 without bubbles is Ra and the resistance value between the electrode A8 and the electrode B9 with bubbles is Rb, the difference between the resistance values is the difference between the output voltages of the parallel resonance impedance measuring means 41. When there is no bubble, Va appears. When there is a bubble, Vb appears. If the identification resistance value is Rref, the identification voltage is Vref. The foam water washing liquid conductivity determining means 26 of the control means 11 can identify that there is no foam when the voltage is higher than the identification voltage Vref, and that there is foam when the voltage is low. The resistance value of the washing liquid and the electric conductivity of the washing liquid have a correlation, and the resistance value and the electric conductivity are said to be the same.

  In the present embodiment, a Colpitts oscillation circuit is used as the high frequency generating means of the foamed water washing liquid conductivity detecting means 10, which includes the inductance of the primary coil of the insulating transformer 33, the capacitor (C 1) 35, and the capacitor (C 2) 36. Once determined, the self-excited oscillation configuration automatically oscillates at the parallel resonance frequency, so that the constants of the components change due to changes in the temperature of the insulating transformer 33, the capacitor (C1) 35, and the capacitor (C2) 36. Also oscillates stably at the parallel resonance frequency.

  Further, since the oscillation is continued with the maximum value of the parallel resonance impedance because it is self-excited, it is suitable for a washing liquid sensor for accurately checking the resistance value of the washing liquid.

  Next, an operation for detecting the conductivity of the washing liquid will be described. First, when an instruction for easy washing is given to the central control means 21 from the operation display means 22 of the control means 11 shown in FIG. 3, the motor control means 24 works after a predetermined amount of washing water is supplied. 1 is driven to rotate the drum 3.

  By the operation of the circulation pump 16, the washing liquid in the drum 3 and the outer tub 2 enters the circulation path 15 from the water intake port 5, and circulates from the discharge port 14 into the drum 3 through the washing liquid sensor 17. Thereby, the water in the circulation path 15 is always equal to the washing liquid in the drum 3 and the outer tub 2. Then, the washing liquid gradually becomes turbid as the dirt dissolves from the laundry by detergent or stirring.

  On the other hand, the amount of the sweat component of the laundry liquid can be captured as a change in the resistance value of the laundry liquid, and FIG. 9 shows the relationship between the amount of the sweat component of the laundry liquid and the resistance value of the laundry liquid. Therefore, by measuring the resistance value of the washing liquid, it is possible to determine the amount of dirt mainly composed of sweat (the main component is sodium chloride) that has melted from the laundry. You can see the degree.

  Next, a method of checking the change in the resistance value of the washing liquid by the foamed water washing liquid conductivity detecting means 10 will be specifically described. As shown in FIG. 6, the washing liquid disappears between the electrode 17a and the electrode 17b for washing liquid conductivity detection immersed in the washing liquid connected to the secondary coil of the insulating transformer 33, and the air is removed. When the parallel resonance impedance on the primary side when the resistance value Z∞ at the time of contact is Z1 and the resistance value when the washing liquid is in contact between the electrode 17a and the electrode 17b is Z2, the parallel on the primary side at that time The resonance impedance is Z12, which is smaller than Z1.

  That is, when the resistance value between the electrode 17a and the electrode 17b of the secondary coil decreases, the parallel resonance impedance on the primary side also decreases. As a result, the amplitude of the sine wave of the Colpitts oscillation circuit is also reduced, and the foam water washing liquid conductivity determination means 26 of the control means 11 connected to the output of the smoothing circuit constituted by the capacitor (C3) 39 and the resistor (R1) 40. The input voltage is also reduced. As described above, the foam water washing liquid conductivity determining means 26 can know the impedance Z1 on the primary side of the insulating transformer 33 by observing the change in the output voltage of the foam water washing liquid conductivity detecting means 10.

  FIG. 9 shows the component amount of sweat per unit volume measured in advance and the resistance value of the washing liquid at that time. FIG. 10 shows the relationship between the primary side impedance Z1 of the insulating transformer 33 and the secondary side impedance (resistance value of the washing liquid immersed in the washing liquid) Z2 of the insulating transformer 33. The electric conductivity of the washing liquid immersed in the washing liquid has a correlation with the resistance value of the washing liquid in contact between the electrode electrode 17a for detection and the electrode rod 17b (the impedance on the secondary side of the insulating transformer 33 is Z1). Judgment can be made. Therefore, from FIG. 10, the impedance Z2 on the secondary side of the insulating transformer 33 is the resistance value of the washing liquid between the electrode 17a and the electrode 17b, that is, the conductivity can be identified.

  Next, FIG. 10 shows that by changing the turns ratio of the primary side coil and the secondary side coil of the insulating transformer 33 to 1: n, bubbles and water can be seen and the conductivity of the washing liquid can be seen. This will be explained with reference. In FIG. 10, the vertical axis represents the primary impedance of the insulating transformer 33 as Z1, and the horizontal axis represents the secondary impedance (the resistance value of the washing liquid immersed in the washing liquid) of the insulating transformer 33 as Z2.

Z1 and Z2 have a relationship of Z1 = (the square of the turns ratio n) × Z2.
For example, when Z1 = 20000Ω and n = 0.5, Z2 = 500Ω,
If n = 1, then Z2 = 20000Ω.
That is, even if the parallel resonance impedance Z1 on the primary side of the insulation transformer 33 is the same, the impedance (resistance value of the washing liquid immersed in the washing liquid) Z2 on the secondary side of the insulation transformer 33 is changed by changing the turn ratio. be able to.

  Thus, by changing the winding ratio to 1: n, it is possible to change the resistance value range of the washing liquid immersed in the washing liquid and the resistance value range for detecting bubbles and water. For example, when Z1 is 20000Ω, if the winding ratio is 0.5, the conductivity of the washing liquid having a resistance value of 100 to 20000Ω can be detected centering around 500Ω, and if the winding ratio is 4, Z2 is 500 kΩ. It is possible to detect bubbles and water having a resistance value of 100 k to 1000 kΩ around the center.

  In this way, the foam water washing liquid conductivity determining means 26 of the control means 11 can detect the conductivity of foam, water, or washing liquid based on the output voltage of the foam water washing liquid conductivity detecting means 10, for example, 1 minute. The electric conductivity (resistance value) of the washing liquid is measured every time, and the state of the washing liquid can be judged and used for controlling the washing process and the rinsing process. For example, if the resistance value is higher than a predetermined value, the resistance value can be determined to be equivalent to tap water, and it can be used for control such as determining that the rinsing is complete and ending the rinsing.

  In addition, when the foam washing water conductivity detecting means 10 is connected to the electrode A8, the electrode B9, the electrode 17a, and the electrode 17b, it may be necessary to connect with a lead wire of about 1 m, and the lead wire is long. Therefore, the influence of noise is a concern, but the output of the secondary coil of the foamed water washing liquid conductivity detecting means 10 is applied with a sinusoidal waveform of the resonance frequency to see the resistance value of the washing liquid. It is not easily affected by other noise and is resistant to noise.

  Furthermore, since the primary coil and the secondary coil are insulated, there is no influence on the human body. Further, since an alternating current is applied to the pair of detection electrodes immersed in the washing liquid, there is less metal corrosion than when a direct current is applied to the electrodes. Furthermore, since the primary side coil and the secondary side coil are insulated, there is no influence on the human body. Since the electrode is directly connected to the secondary coil of the magnetic coupling means, there is nothing to switch even if noise is applied to the electrode, and no malfunction occurs.

  In addition, since the noise generated from the washing motor 4 and the like is mainly electric noise having a frequency fm for driving the motor 4, the resonance frequency of the primary coil inductance, the capacitor (C1) 35 and the capacitor (C2) 36 is obtained. By setting fr to a frequency equal to or higher than fm, the influence of noise can be prevented. Specifically, since the drive frequency of the motor 4 is around 15 kHz, the resonance frequency is set to 30 kHz or more.

  As described above, the washing machine according to the present invention uses one detection means for a plurality of electrodes having a plurality of functions such as an electrode for detecting the conductivity of the washing liquid and an electrode for detecting foam and water. This is useful as a washing machine because the number of parts can be reduced and the size of the board can be reduced.

2 Outer tank 3 Drum 4 Motor 8 Electrode A (electrode for detecting foam water)
9 Electrode B (Electrode for detecting foam water)
DESCRIPTION OF SYMBOLS 10 Foam water washing liquid electric conductivity detection means 11 Control means 17 Laundry liquid sensor 17a Electrode A (electrode for washing liquid electric conductivity detection)
17b Electrode B (Electrode for detecting conductivity of washing liquid)
27 Foam water detection sequence means 28 Washing liquid conductivity detection sequence means 33 Insulation transformer (magnetic coupling means)
35 Capacitor (C1)
36 Capacitor (C2)

Claims (4)

A drum for storing laundry, an outer tub in which the drum is rotatably included, a motor for rotationally driving the drum, a magnetic coupling means having an insulating structure, and foam water disposed in the outer tub are detected. A pair of electrodes, a pair of electrodes for detecting the electric conductivity of the washing liquid, the electrode for detecting foam water and the electrode for detecting the electric conductivity of the washing liquid are connected to a secondary coil of the magnetic coupling means, A capacitor connected in parallel with the primary coil of the magnetic coupling means, and a high frequency generating means for causing the capacitor connected in parallel with the primary coil of the magnetic coupling means to resonate in parallel at a frequency higher than twice the driving frequency of the motor; A parallel resonance impedance measuring means connected to the output of the high frequency generating means for measuring the impedance at the time of parallel resonance; and a control means for sequentially controlling each step of washing, rinsing and dehydration, the control The stage has foam water detection sequence means for detecting foam and water, and washing liquid conductivity detection sequence means for detecting the conductivity of the washing liquid, and the conductivity of the foam water and the washing liquid is detected by each electrode. Washing machine that changes the washing control sequence. 2. The washing machine according to claim 1, wherein the secondary coil of the insulating transformer has one terminal with an intermediate number of turns to increase the number of turns. The secondary coil of the insulation transformer is provided with a switching means for switching between an electrode for detecting the conductivity of the washing liquid and an electrode for detecting the foam water by the washing liquid conductivity detection sequence means and the foam water detection sequence means. The washing machine described. The washing machine according to claim 1, wherein the resonance frequency is set to 30 kHz or more.

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