JP4141738B2 - Washing machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a washing machine.
[0002]
[Prior art]
Examples of means for detecting the level of water accumulated in the outer tub and the vibration of the outer tub and a washing machine that controls the washing operation based on the detection result include the following.
[0003]
As a first conventional example, a dehydrating combined washing machine described in Japanese Patent Application Laid-Open No. 9-294899 is provided with a water level detecting means for changing the amount of iron core inserted into the coil according to the water level in the outer tub. The water level / vibration detecting means is configured to change the insertion amount due to the iron core vibrating due to the vibration of the outer tub, and the water level / vibration detecting means detects the water level in the outer tub and the vibration of the outer tub. It is the structure which performs washing | cleaning and control of spin-drying | dehydration operations, such as rotation control of the inner tank at the time of spin-drying | dehydration based on the detection result.
[0004]
As a second conventional example, a washing machine described in Japanese Patent Laid-Open No. 9-94380 is configured to detect the water level in the outer tub and the vibration of the outer tub with one water level sensor. Specifically, two magnetic bodies to be inserted into the coil of the water level sensor are provided, the amount of insertion of the first magnetic body changes according to the water level in the outer tank, and the second magnetic body has the outer tank. The amount of insertion changes according to the vibration of the upper end of the suspension to be supported.
[0005]
[Problems to be solved by the invention]
The first conventional example can detect the vibration component in the insertion direction of the iron core, that is, the longitudinal direction of the coil, but cannot detect the vibration component in the vertical direction. Therefore, there is a problem that even if vibrations in the vertical direction of the outer tub can be detected, vibrations in the front-rear and left-right directions cannot be detected.
[0006]
The second conventional example is configured to detect the vibration of the upper end portion of the suspension, that is, the attachment portion to the outer frame, but this vibration is not necessarily proportional to the vibration of the outer tub itself. Therefore, it is difficult to correctly detect the vibration state of the entire outer tub. Further, as in the first conventional example, the vibration component in the magnetic material insertion direction, that is, the longitudinal direction of the coil can be detected, but the vibration component in the vertical direction cannot be detected.
[0007]
Further, since the two conventional examples detect the water level and the vibration by the change of the inductance value of the coil, the water level and the vibration cannot be detected at the same time. For example, if a small amount of water remains in the outer tank and dewatered in a state where vibration can be suppressed by the mass effect, it is difficult to identify whether the detection result is a change in water level due to rotation or vibration. It is.
[0008]
Therefore, it is difficult to execute control suitable for starting washing and dehydration and reducing vibration noise during dehydration based on the detection signal (detection result) output from the conventional detection means.
[0009]
One object of the present invention is to provide a washing machine capable of reducing washing and dehydration activation and vibration noise during dehydration by a water level detecting means and vibration detecting means having a simple configuration.
[0010]
Another object of the present invention is to realize a water level detection means and a vibration detection means capable of executing control suitable for starting washing and dehydration and reducing vibration noise during dehydration with a simple configuration and low cost. There is.
[0011]
Still another object of the present invention is to realize a water level / vibration sensor that realizes the water level detection means and the vibration detection means with a simple structure and at a low cost.
[0012]
[Means for Solving the Problems]
The features of the washing machine in the present invention are based on the output signal of the water level detecting means and the vibration detecting means configured using the water level / vibration sensor, and the rotation speed signal of the washing / dehydrating tub output from the rotation speed detection means, It is to reduce vibration noise during washing and dehydration start-up and dehydration by performing optimal rotation speed control of the rotor blades or the washing and dehydrating tub (inner tub) by the control means.
[0013]
  The water level / vibration sensor has a magnetic body in which the amount of insertion into the coil is proportional to the water level in the water receiving tank (outer tank) and a magnet supported by a spring arranged in the vicinity of the outer periphery of the coil.The magnetic flux generated from the magnet is interlinked with the coil.The water level detecting means is constituted by a water level sensor circuit that constitutes an oscillation circuit using the inductance of the coil of the water level / vibration sensor.AboveThe vibration detecting means is constituted by a vibration sensor circuit that processes an induced voltage of the coil caused by a change in the amount of magnetic flux linkage to the coil.
[0014]
Then, the control means refers to the output signals of the water level detection means and the vibration detection means, and in the dehydration process, the dehydration process starts centrifugal dehydration leaving a certain amount of washing water in the washing tub, and dewatering due to the mass effect of the washing water. Suppresses external tank vibration during startup. Specifically, the water level detection means monitors the water level and opens the drain electromagnetic valve to discharge the washing water. Then, when the water level reaches a certain level, the drain electromagnetic valve is closed and the rotation of the inner tank is started. When the laundry is largely offset within a predetermined time from the start of rotation and the outer tub collides with the outer frame, the outer frame vibration due to the collision is detected based on the output signal from the vibration detecting means, and the dehydration activation is stopped ( The rotation of the inner tank that is the excitation source is stopped). If no collision is detected, the drain electromagnetic valve is restarted after a predetermined time, and dehydration is continued.
[0015]
Further, in the dehydration process, the inner tub receives a partial load caused by the side of the laundry and the like and rotates and vibrates, and the outer tub containing the same vibrates. This uneven load generates a moment force on the rotation axis of the inner tank, and applies a large moment load to the connecting portion between the inner tank and the rotation axis. For this reason, when the deviation of the laundry is large, that is, the rotational vibration of the inner tub is large and the vibration of the outer tub accompanying it is large, there is a possibility that the connecting portion is damaged due to moment load and it becomes a dangerous state. The moment force is proportional to the square of the spin speed, and thus limits the spin speed.
[0016]
After the dehydration start is started, while monitoring the dehydration rotation speed by the rotation speed detection means, if the dehydration rotation speed reaches a predetermined value, for example, 600 rpm, based on the output signal of the vibration detection means, After detecting the vibration and comparing with the predetermined threshold value, set the final dewatering rotation speed at which the connecting part does not cause breakage, and then accelerate to the set final dewatering rotation speed and after reaching the final dewatering rotation speed Perform dehydration for a predetermined time. Thereby, it becomes possible to avoid the fastening part damage which arises from the one side of a laundry, etc., and can provide a safe washing machine.
[0017]
Further, when the outer tub vibrates during the dehydration steady state after reaching the final dewatering speed, the vibration amplitude of the outer frame is detected based on the output signal of the vibration detecting means. At the time of steady dehydration, the correlation between the vibration of the outer tank, that is, the outer frame, and noise is high. For this purpose, the control means controls the number of revolutions of the inner tub as a vibration source based on the vibration amplitude of the outer tub. A specific control method is to set an upper limit value for the number of rotations of the inner tub according to the magnitude of vibration, monitor the number of rotations of the inner tub by the number of rotation detection means, and set the number of rotations to be equal to or less than the upper limit value. Control to hold. When the rotation speed is set to the upper limit value or less due to large vibration, the dehydration time is increased according to the rotation speed.
[0018]
In the washing process, the water level (water amount) and the vibration of the outer tub are simultaneously detected using a water level / vibration sensor to control the rotation speed or rotation inversion period of the rotor blades. This is because the primary resonance frequency of the outer tub in which water is stored and the system that suspends the water accords with the frequency of the rotating blade or the rotation inversion period of the excitation blade, and the outer tub shakes greatly and the outer frame This is to prevent the collision. When the output signal of the vibration detection means exceeds the threshold value, the water level is monitored with reference to the output signal of the water level detection means in order to shift the primary resonance frequency of the system described above from the excitation source frequency. Washing water is supplied or drained while monitoring vibration with reference to the output signal of the detection means. Alternatively, the rotational speed or rotation reversal period of the rotor blade is changed in order to shift the excitation source frequency from the primary resonance frequency of the system while monitoring the vibration with reference to the output signal of the vibration detecting means.
[0019]
According to the present invention as described above, it is possible to independently and simultaneously detect the water level and vibration in the outer tub which is a water receiving tub using a simple and inexpensive water level and vibration sensor. Further, safety can be improved by detecting a collision between the outer tub and the outer frame at the time of dehydration activation and stopping the activation.
[0020]
In addition, it is possible to avoid breakage of the connecting portion between the inner tub and the rotating shaft due to moment load generated from the side of the laundry, and a safe washing machine can be provided.
[0021]
Further, it is possible to maintain the dewatering performance, suppress the noise below a certain level, and prevent excessive noise during dewatering.
[0022]
Furthermore, washing performance can be maintained, collision between the outer tub and the outer frame can be prevented, excessive noise during washing can be prevented, and safety can be improved.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an external view of a fully automatic washing machine according to an embodiment of the present invention, and FIG. 2 is a longitudinal side view taken along line AA in FIG.
[0024]
The exterior of this fully automatic washing machine is constituted by an outer frame 1 made of steel, a top cover 2 and an operation panel 3 attached to the outer frame 1.
[0025]
The top cover 2 includes a lid 2a, an insertion port 2b for loading laundry, a rear storage box 2c for mainly storing parts related to water supply, and a front operation box 2d for mainly storing electrical parts. . The operation panel 3 is fixed so as to cover the upper surface of the front operation box 2d.
[0026]
The outer tub 4 serving as a water receiving tub is supported in a suspended state in the outer frame 1 from the upper four corners of the outer frame 1 by a vibration isolator 5b including a suspension rod 5a and a coil spring, a sliding ring, and the like. Rinsing water and rinsing water in the rinsing process (hereinafter referred to as washing water) are stored. In this outer tub 4, a stainless steel washing and dewatering tub 6 (hereinafter referred to as a washing tub or an inner tub) is rotatably provided. A large number of dewatering holes 6a are provided on the side surface of the washing tub 6, and a balancer 6b is provided on the upper edge. A rotating blade 7 is rotatably provided at the center bottom of the washing tub 6. A support plate 8 is attached to the outside of the bottom surface of the outer tub 4, and a driving device 9 is fixed to the support plate 8.
[0027]
The drive device 9 includes an inner rotor type DC brushless motor 9a, and a transmission device 9b incorporating a gear reduction mechanism and a clutch mechanism. A DC brushless motor 9a is disposed below the transmission device 9b, and an input shaft of the transmission device 9b is fastened to a rotation shaft (rotor) of the DC brushless motor 9a. The transmission device 9b includes two coaxial output shafts 9d, and selectively transmits the rotation of the DC brushless motor 9a to the two output shafts 9d by a clutch mechanism (not shown) in the device. The two output shafts 9 d of the transmission device 9 b penetrate the bottom wall of the outer tub 4 in a watertight state and project into the outer tub 4, and are connected to the rotary blade 7 and the washing tub 6.
[0028]
In the washing process and the rinsing process, the driving device 9 stops the washing tub 6 by the transmission device 9b, and reduces the rotation of the DC brushless motor 9a by the gear reduction mechanism of the transmission device 9b and transmits it to the rotary blade 7 The rotary blade 7 is rotated clockwise (forward) and counterclockwise (reverse). Further, in the dehydration process, the rotation of the DC brushless motor 9a is transmitted to the washing tub 6 and the rotary blade 7 without being decelerated by the gear reduction mechanism, and these are rotated at a high speed in one direction.
[0029]
A drain electromagnetic valve 10 for draining washing water is provided on the bottom surface of the outer tub 4, and the washing water is discharged outside the washing machine through a drain hose 11 connected to the drain electromagnetic valve 10.
[0030]
FIG. 3 shows an arrangement state of each electrical component in the front operation box 2d, and is a plan view of the front operation box 2d with the operation panel 3 on the front operation box 2d removed (in FIG. 1). It is a cross-sectional plan view shown by the BB line.
[0031]
In the front operation box 2d, a water level / vibration sensor 12 that detects the water pressure in the outer tub 4 and detects vibrations in the outer tub 4, a lid open / close sensor 13, a lid lock mechanism 14, and a tank shake sensor 15 are detected. Is provided. In addition, the components shown with a broken line in the figure are a substrate of a washing and dehydration process control unit 20 as a control means to be described later, and the components shown with a dashed line are the outer periphery of the outer tub 4.
[0032]
Incidentally, a water supply electromagnetic valve 27 for supplying water to the outer tub 4, a water supply tap 27a connected to the water supply electromagnetic valve 27, a bath water pump 28, a bath water supply tap 28a connected to the bath water pump 28, etc. It is stored in the storage box 2c.
[0033]
4A and 4B show the water level / vibration sensor 12. FIG. 4A is a top view of the water level / vibration sensor 12, and FIG. 4B is a longitudinal side view taken along line DD in FIG.
[0034]
The inside of the casing of the water level / vibration sensor 12 is separated into two rooms by a rubber film 12a as a diaphragm. A ferrite core 12c, which is a columnar magnetic body that moves together with the rubber film 12a, is attached to the upper chamber 12b side of the rubber film 12a, and is pressed downward by a spring A12d from the housing. A coil 12e is disposed around the ferrite core 12c. The coil 12e and the capacitor 12g are connected in parallel between the two terminals 12f. The upper chamber 12b opens to the atmosphere through the air hole 12h.
[0035]
A vibrator 12k constituted by a leaf spring 12i and a magnet 12j fixed to the tip thereof is provided near the upper part of the coil 12e outside the housing. In the vibrator 12k, the other end of the leaf spring 12i is fixed to the water level / vibration sensor casing, the magnet 12j is positioned in the vicinity of the coil 12e, and the water level / vibration sensor casing is vibrated in the DD line direction. Then, the magnet 12j is configured to vibrate in the horizontal direction indicated by the arrow in the figure, and the magnetic flux generated from the magnet 12j and interlinked with the coil 12e changes in accordance with the vibration of the magnet 12j. The induced voltage is generated between both ends of the coil 12e, that is, between the terminals 12f in accordance with the above law.
[0036]
A connection port 12n is formed in the lower chamber 12m below the rubber film 12a, and one end of the water level sensor tube 12p is connected thereto. As shown in FIG. 2, the other end of the water level sensor tube 12 p is connected to an air chamber 12 q communicating with the inside of the outer tub 4 at the lower part of the outer tub 4. A pressure is applied to the rubber film 12a in the vibration sensor 12 to push the rubber film 12a upward, and the ferrite core 12c is inserted (entered) into the coil 12e to change the inductance value of the coil 12e.
[0037]
The lid opening / closing sensor 13 includes a hall element 13a and a magnet 13b. The magnet 13b is configured to fit in the E position of the lid 2a opposite to the hall element 13a and detect the open / closed state of the lid 2a based on the presence or absence of the hall voltage.
[0038]
The lid lock mechanism 14 has a configuration in which a hook 14b driven by a solenoid (not shown) is hung on a fitting hole 14a opened at the D position of the opposite lid 2a to lock the opening of the lid 2a.
[0039]
The tank shake sensor 15 is a lever switch that operates according to the swing of the outer tank 4. It comprises a micro switch (not shown) and a lever 15a for pressing the micro switch. As shown in FIG. 2, one end of the lever 15a passes through the front operation box 2d and is close to the upper part of the outer tub 4. The outer tank 4 is installed so as to come into contact with the lever 15a when the outer tank 4 swings greatly.
[0040]
An operation panel 3 is attached as an upper lid on the upper surface of the front operation box 2d, and a substrate for a washing and dehydration process control unit 20 composed of a microcomputer or the like is provided below the operation panel 3.
[0041]
The operation panel 3 is provided with a power switch 60, a 7-segment LED display 61, an LED display 62, and various operation switches 63, and a user operates the washing machine with the operation switch 63. The operation state is configured so that it can be confirmed by the display by the display devices 61 and 62 and the electronic sound from the buzzer 64.
[0042]
FIG. 5 is an electric block diagram of the washing and dehydration process control unit 20 configured around the microcomputer 35.
[0043]
The control unit 20 is connected to a commercial AC power source via the power switch 60.
[0044]
The output terminal of the microcomputer 35 is connected to the drive circuits 36a to 36e, and the water supply solenoid valve 27, the bath water pump 28, the lid lock mechanism (lid lock solenoid) 14, the drainage solenoid valve 10, the transmission device (clutch solenoid). The supply of commercial power to 9b etc. is controlled to control the opening / closing or rotation of these.
[0045]
The power supply circuit 37 steps down, rectifies, and smoothes a commercial AC power supply to generate a DC voltage necessary for the microcomputer 35 and other circuits.
[0046]
A voltage doubler rectifier circuit 38 connected to a commercial AC power supply rectifies the commercial AC power supply to generate a DC voltage of about 280 V and supplies it to the PWM inverter circuit 39. The PWM inverter circuit 39 includes an IGBT module and a drive circuit. By applying a PWM signal to the gate terminal of the IGBT, the DC voltage output from the voltage doubler rectifier circuit 38 is chopped, and each UVW phase of the DC brushless motor 9a. A three-phase alternating current is supplied to the field winding. The IGBT module is a three-arm three-phase bridge inverter circuit, and each arm is composed of a set of IGBTs and flywheel diodes connected in antiparallel to each other. Each gate terminal of the IGBT is driven by a PWM signal of a drive circuit.
[0047]
The DC brassless motor 9a incorporates three sets of hall elements 9c as rotor position detecting means, and each hall element 9c is arranged at every 120 electrical degrees. The position of the rotor is detected by this Hall element 9c and transmitted to the microcomputer 35. The microcomputer 35 calculates and outputs a PWM signal that flows through each IGBT based on the information on the rotor position and rotation speed, controls the drive circuit, and controls the field of each UVW phase of the stator. Control is performed to apply a PWM rectangular wave voltage whose peak value is approximately the input DC voltage to the winding. At this time, the current flowing in each field winding is a sine wave due to the inductance and capacity of the motor winding. That is, a three-phase sine wave current is supplied to each field winding. If the current in the UVW phase is 120 degrees in this order, the DC brassless motor 9a rotates in the clockwise direction, and reverses in the counterclockwise direction in the phase relation that reverses the UV phase. The rotation speed of the DC brushless motor 9a is controlled by the duty of the PWM signal, that is, the conduction ratio.
[0048]
The EEPROM 40, which is an electrically rewritable ROM, mainly stores operation states in the previously performed washing and dewatering steps. The microcomputer 35 can know the operating state of the washing machine or the set value of the user based on the output values of various sensors during the washing and dehydrating process. For example, the number of washings that have been performed so far, the occurrence of on-board electrical components such as disconnection of the bath water pump, the set values for washing and dehydration performed by the user (washing course name, presence / absence of bath water supply, washing time, rinsing By storing information such as the number of times and the dehydration time in the EEPROM 40 each time, the convenience in the next washing and dehydration process can be enhanced. These settings can be reflected in the initial display on the operation panel 3.
[0049]
The internal ROM of the microcomputer 35 stores a sequence program for controlling the washing and dehydrating processes, a program for driving the brushless motor 9a, sequence data, and the like.
[0050]
The input terminals of the water level sensor circuit 16 and the vibration sensor circuit 17 are connected to the terminal 12f of the water level / vibration sensor 12, and the output terminals are respectively connected to the microcomputer 35 to the input terminals.
[0051]
Further, the input / output terminal of the microcomputer 35 is connected to the lid opening / closing sensor 13, the tank shake sensor 15, and the operation switch 63 via the operation switch input circuit 51, and the output terminal is connected to the 7-segment LED display 61. The LED display 62 and the buzzer 64 are connected.
[0052]
FIG. 6 is a circuit diagram showing the internal configuration of the water level sensor circuit 16 and the vibration sensor circuit 17. The water level / vibration sensor 12 and the water level sensor circuit 16 constitute water level detection means, and the water level / vibration sensor 12 and the vibration sensor circuit 17 constitute vibration detection means.
[0053]
First, the water level detection means constituted by the water level / vibration sensor 12 and the water level sensor circuit 16 will be described.
[0054]
The water level sensor circuit 16 is a closed loop circuit 16a of an inverter two-stage series circuit, and forms a rectangular wave self-excited oscillation circuit by connecting a parallel resonance circuit of a coil 12e of the water level / vibration sensor 12 and a capacitor 12g. A rectangular wave signal near the parallel resonance frequency (about 20 kHz) of 12e and the capacitor 12g is oscillated and output.
[0055]
The water level (water pressure) accumulated in the outer tub 4 is converted into air pressure in the air chamber 12q, and pressure is applied to the rubber film 12a in the water level / vibration sensor 12 via the water level sensor tube 12p. The rubber film 12a is pushed upward by this pressure, and the ferrite core 12c is inserted into the coil 12e. For this reason, the inductance value of the coil 12e changes according to the water level.
[0056]
Since the coil 12e constitutes a parallel resonance circuit with the capacitor 12g and determines the self-excited oscillation frequency of the water level sensor circuit 16, the oscillation frequency also changes according to the water level when the impedance value of the coil 12e changes according to the water level. . That is, as is well known, the self-excited oscillation frequency of the water level sensor circuit 16 is determined by the inductance value of the coil 12e and the capacitance value of the capacitor 12g. In this embodiment, the capacitance of the capacitor 12g is fixed. This is proportional to the inductance value of 12e. This inductance value is proportional to the amount of insertion x of the ferrite core 12c into the coil 12e. Constant). The pressure p is proportional to the water level (the height of the water column) accumulated in the outer tub 4. As a result, the change in the water level becomes a change in the frequency. Therefore, the microcomputer 35 can detect the water level by inputting the oscillation output signal of the water level sensor circuit 16 and measuring the frequency.
[0057]
FIG. 7 is a characteristic diagram showing the relationship between the water level in the outer tub 4 and the oscillation frequency of the water level sensor circuit 16. Since the outer diameter of the outer tub 4 is known, the amount of water can be obtained from the water level. The microcomputer 35 stores in advance the relationship between the self-excited oscillation frequency of the water level sensor circuit 16 and the amount of water as table data, and displays the amount of water supply and the like on the display 61 of the operation panel 3.
[0058]
Next, a vibration detecting means constituted by the water level / vibration sensor 12 and the vibration sensor circuit 17 will be described. The vibration detection in this embodiment is measurement of vibration amplitude, and the vibration amplitude is hereinafter simply referred to as amplitude.
[0059]
The vibration of the outer tub 4 is transmitted from the suspension bar 5a to the outer frame 1. Along with this, the water level / vibration sensor 12 fixed to the front operation box 2d on the outer frame 1 vibrates. For this reason, the magnet 12j at the tip of the vibrator 12k of the water level / vibration sensor 12 vibrates relative to the coil 12e by the vibration of the outer frame 1. Since the magnetic flux of the magnet 12j is attached at a position where the magnetic flux is linked to the coil 12e, an induced voltage according to Faraday's law is generated in the coil 12e due to a change in the magnetic flux due to vibration. The induced voltage generated in the coil 12e is proportional to the temporal change rate of the magnetic flux density linked to the coil 12e. If the magnet 12j vibrates, the relative distance between the magnet 12j and the coil 12e changes, so that the magnetic flux density also changes and an induced voltage is generated in the coil 12e. As the vibration amplitude is larger, the fluctuation range of the relative distance is larger, so that the fluctuation range of the magnetic flux density is larger and the induced voltage is higher. Also, the higher the vibration frequency, the higher the induced voltage.
[0060]
The vibration of the outer tub 4 is generally a combination of front and rear, left and right vibration components. This vibration propagates from the suspension bar 5 a to the outer frame 1 installed horizontally, and vibrates the front operation box 2 d of the top cover 2 on the outer frame 1. For this reason, the vibration directions of the outer frame 1 and the front operation box 2d fixed to the outer frame 1 are mainly horizontal directions such as front and rear and left and right. Therefore, the horizontal direction is also the main vibration direction of the vibrator 12k of the water level / vibration sensor 12 installed in the front operation box 2d by this horizontal excitation force. Therefore, as shown in FIG. 4, the vibrator 12k is attached to the casing of the water level / vibration sensor 12 so that the thickness direction of the leaf spring 12i, that is, the direction in which vibration easily occurs is horizontal. That is, the sensitivity is increased with respect to the horizontal component of the outer frame vibration.
[0061]
On the other hand, the outer frame 1 also has a natural vibration frequency. In the case of a general washing machine, the outer frame volume is substantially determined by the washing capacity. For example, in a washing machine having a washing capacity of 8 kg, the natural vibration frequency is 10 to 11 Hz. Further, since the mass of the outer tub 4 and the inner tub 4 suspended by the top cover 2 or the suspension rod 5a is added to the outer frame 1, the resonance characteristic at this natural vibration frequency is broad. As a result, when the vibration frequency of the outer tub 4 serving as the excitation source matches the natural vibration frequency of the outer frame 1, the vibration of the outer frame 1 becomes larger than at other frequencies.
[0062]
As described above, since the induced voltage generated in the coil 12e due to the vibration of the vibrator 12k due to the vibration of the outer frame 1 is proportional to the temporal change rate of the magnetic flux density, the vibration amplitude of the magnet 12j is the same. Has a differential characteristic that increases in proportion to the vibration frequency. Therefore, the higher the rotation speed of the washing tub 6 that is the excitation source, the higher the vibration frequency of the outer tub 4 and the higher the induced voltage. In order to obtain a voltage proportional to the vibration amplitude of the outer tub 4 regardless of the number of rotations of the washing tub 6, it is necessary to correct the differential characteristic using an integrating circuit. As described above, since the magnetic flux change is proportional to the position change of the outer tub 4, that is, the vibration speed, the induced amplitude due to the magnetic flux change is a value obtained by integrating the vibration amplitude. For this purpose, the vibration sensor circuit 17 is provided with an integrating circuit. Thereby, the vibration amplitude of the outer tub 4 can be accurately detected at a wide vibration frequency.
[0063]
In addition, since the capacitor 12g is connected in parallel to the coil 12e, the induced voltage is attenuated by this, but the influence can be ignored. As described above, when the resonance frequency of the coil 12e and the capacitor 12g is set to 20 kHz, the capacitor capacity is about several nF. On the other hand, the frequency of the induced voltage, that is, the rotation frequency of the inner tank 6 is 20 Hz or less. At this frequency, the impedance of the capacitor 12g connected in parallel to the coil 12e is high, and the attenuation of the induced voltage can be ignored. The coil 12e of the water level / vibration detection means 12 is also connected to the water level detection circuit 16 at the same time. The oscillation frequency in this circuit is as high as 20 kHz, and the frequency of the voltage induced by vibration is 20 Hz or less (washing) Since the number of rotations of the tank 6 is 1200 rpm or less, there is no mutual influence (the 20 kHz component is attenuated by the integration circuit in the vibration sensor circuit 17 and does not affect the subsequent circuit. Does not affect the inductance value of the coil 12e). From this, it is possible to detect the water level and the vibration at the same time.
[0064]
The vibration sensor circuit 17 includes an amplification / integration circuit 17a that inputs and amplifies and integrates the induction voltage of the coil 12e, an amplification / rectification circuit 17b that amplifies and half-wave rectifies the output signal of the amplification / integration circuit 17a, A smoothing circuit 17c is provided for smoothing the output signal of the amplifying / rectifying circuit 17b and converting it into a DC voltage. However, in order to detect only the difference between the outer tub vibration at a specific inner tub (washing tub) rotation speed or the vibration due to the unbalance amount, there is no need for an integrating circuit. Further, the rectification and smoothing circuit may be omitted, and the amplified signal may be captured by the AD conversion input terminal of the microcomputer 35 and rectified and smoothed by software processing. In this case, as shown in FIG. 8, the vibration sensor circuit 17 is transformed into a simple amplifier 17e in which a simple low-pass filter 17d for removing the rectangular wave signal (about 20 kHz) of the water level sensor circuit 16 is connected to the input. Can do.
[0065]
The vibrator 12k has a natural frequency determined by the spring constant k of the spring 12i and the mass m of the magnet 12j, and the frequency f is f = 1 / 2π · (k / m) 1/2. As described above, the dehydration rotation frequency is approximately 20 Hz or less. For this reason, if the natural frequency of the vibrator 12k is not set to 20 Hz or more, the induced voltage frequency characteristic due to the magnet vibration resonates within the dehydration rotation range and a peak occurs in the induced voltage (sensor output). This will interfere with vibration detection. That is, the vibrator 12k needs to be designed so as not to have a natural vibration in the dehydration rotation frequency range.
[0066]
FIG. 9 shows a case where the vibration sensor circuit 17 shown in FIG. 8 processes the induced voltage generated when the water level / vibration sensor 12 shown in FIG. 4 is vibrated by a sine wave of 0.4 mm in the horizontal direction. FIG. Here, the natural vibration frequency of the vibrator 12k is designed to be 20 Hz. It has a sharp peak at a natural frequency of 20 Hz and also has a peak at frequencies of 1/2, 1/3, 1/4,. FIG. 10 shows the excitation amplitude and output characteristics at 10 Hz, which is a half frequency, and 13 Hz, which is off the peak. It can be seen that the output is proportional to the excitation amplitude even at 1 / n resonance and other frequencies.
[0067]
In general, the actual vibrator 12k has non-linearity in component parts, processing, and attachment, and has some resonance characteristics (others) even at a frequency N times or 1 / N (N is an integer of 2 or more) times the natural frequency. It is easier to vibrate with respect to the frequency. In FIG. 9, 10 Hz (1/2), approximately 7 Hz (1/3), and 5 Hz (1/4) correspond to this.
[0068]
Next, the control of the dehydration process performed using the water level detection means and the vibration detection means configured by combining the water level / vibration sensor 12, the water level sensor circuit 16, and the vibration sensor circuit 17 will be described in detail.
[0069]
FIG. 11 is a characteristic diagram showing an outline of the relationship between the vibration amplitude of the outer tub 4 and the outer frame 1 and the dehydration rotation frequency (the number of rotations of the washing tub 6) from the start of dehydration to the steady state when there is a cloth piece. is there. In the figure, the curve (a) shows the vibration characteristics of the outer tub 4, the curve (b) shows the vibration characteristics in the horizontal direction of the outer frame 1, and (c) shows the output of the water level / vibration sensor 12.
[0070]
The support system consisting of the suspension bar 5a, the support device 5b, and the outer tub 4 incorporating the washing tub 6 is driven by the DC brushless motor 9a to rotate the washing tub 6, and the rotation speed of the washing tub indicated by the curve (a) is outside. Has tank vibration characteristics. When the dehydration is started, the vibration of the primary resonance due to the translational motion near the rotation speed of 50 rpm, the vibration of the secondary resonance due to the conical motion near 150 rpm, and the vibration at the time of steady dehydration (about 900 rpm) continue.
[0071]
This vibration is transmitted to the outer frame 1 and the water level / vibration sensor 12 through the suspension bar 5a.
[0072]
Since the vibration of the primary and secondary resonances of the outer tank vibration is low in frequency, the outer tank vibration is difficult to transmit to the outer frame, and the outer frame vibration and the sensor output are small. When the rotational frequency of the washing tub 6 approaches the resonance (natural vibration) frequency (near 10 Hz) of the outer frame 1, the vibration of the outer frame 1 also increases and the vibration applied to the vibrator 12k also increases. / 4, 1/3, 1/2 Resonance (natural vibration) frequency greatly vibrates, and thereafter increases in proportion to the vibration frequency (rotational speed) of the outer tub 4. The vibration of the outer frame 1 is about 1/10 of the vibration of the outer tub 4, and the water level / vibration sensor 12 installed in the outer frame 1 is required to have high sensitivity. For this reason, the 1 / n resonance frequency described above is advantageous as the frequency of vibration detection (dehydration speed). Furthermore, it is clear that it is further advantageous if this is in the vicinity of the resonance frequency of the outer frame 1.
[0073]
The installation position of the water level / vibration sensor 12 may be higher than the level of water stored in the outer tub 4 in order to detect the water level. On the other hand, in order to detect the vibration of the outer tub 4, it is desirable in terms of sensitivity that the water level / vibration sensor 12 is directly fixed to the outer tub 4. Therefore, in order to detect the vibration of the outer tub 4, it is conceivable to attach the water level / vibration sensor 12 to the outer tub 4. However, the vibration force of the outer tub 4 is large, and a large acceleration is applied to the members constituting the water level / vibration sensor 12, which may reduce the reliability. For example, there is a possibility of malfunction due to disconnection of the wiring connecting the terminal 12f of the coil 12e and the vibration sensor circuit 17. In this sense, it is better to install in the front operation box 2d fixed to the outer frame 1 as in this embodiment. In this case, the vibration applied to the water level / vibration sensor 12 is small, and the vibrator 12k is configured to easily vibrate in the horizontal direction as described above, or the natural vibration frequency of the vibrator 12k is the outer frame natural vibration frequency. Ingenuity to increase the detection sensitivity such as is necessary.
[0074]
Collision detection
An operation for detecting that the outer tub 4 has swung around due to the cloth piece at the start of dehydration and collided with the outer frame 1 using the water level / vibration sensor 12 will be described.
[0075]
Conventionally, a tank shake sensor 15 has been used to detect an outer tank collision with the outer frame 1. As shown in FIG. 11, at the time of dehydration activation, that is, at the primary and secondary resonances, a large vibration amplitude is shown in several tens of seconds from the activation to the steady rotation. The tank shake sensor 15 is mainly intended to detect vibration during primary or secondary resonance. However, since the vibration detection position is one place with the switch lever 15a, the shake of the outer tub 4 cannot always be detected reliably. There is no guarantee that the outer tub 4 pushes the lever 15a when the outer tub 4 swings so as to collide with the outer frame 1 except at the position of the lever 15a.
[0076]
FIG. 12 (a) shows that the outer tub 4 swings greatly due to a large cloth side and the outer tank vibration amplitude, outer frame vibration amplitude, and induced voltage output of the coil 12e (vibration sensor) when it collides with the outer frame 1 are shown. The time change characteristic of the output of the circuit 17 is shown. (B) has shown the case where it did not collide as reference.
[0077]
When the vibration amplitude value of the outer tub 4 is saturated due to the collision, the outer frame 1 is greatly shocked and vibrated by the collision, and the output of the induced voltage of the coil 12e jumps due to this vibration excitation. This is because the vibrator 12k composed of the spring 12i and the magnet 12j vibrates at the natural vibration frequency due to the impact of the collision, and an induced voltage is generated by this vibration.
[0078]
In the dehydration step, centrifugal dehydration is started with a certain amount of washing water remaining in the washing tub 6. This is to suppress the outer tank vibration at the start of dehydration by the mass effect of washing water. The amount of washing water to be left is detected by a water level detecting means constituted by the water level / vibration sensor 12 and the water level sensor circuit 16. Specifically, the drainage electromagnetic valve 10 is opened and the washing water is discharged while monitoring the water level based on the relationship between the output signal of the water level sensor circuit 16 and the water level (see FIG. 7). When the water level reaches a certain level, the electromagnetic drain valve 10 is closed and the rotation of the washing and dewatering tub 6 is started.
[0079]
Simultaneously with the start of dehydration, the microcomputer 35 samples and monitors the output signal of the vibration sensor circuit 17 having no integrating circuit for a certain period of time. For example, monitoring is performed every 10 ms for 3 seconds. If the output signal obtained by connecting the coil 12e to a simple amplifier circuit exceeds the threshold value indicated by the chain line in FIG. 12, the power supply to the DC brushless motor 9a is immediately stopped. Further, after confirming that the washing tub 6 has stopped rotating, the lid lock mechanism 14 is released. Then, the alphanumeric characters “C4” and the like are blinked and displayed on the 7-segment LED display 61 as an error code, and the user is warned with a short-time electronic sound of the buzzer 64.
[0080]
When no collision is detected (when the threshold value is not exceeded), the drainage electromagnetic valve 10 is restarted after a predetermined time, and the dehydration is continued while draining the washing water. In the conventional apparatus, since the water level and the vibration cannot be detected independently and simultaneously, it is impossible to perform such control.
[0081]
In this embodiment, even if the outer tub 4 collides with the outer frame 1 at any position, the vibration of the outer frame 1 due to the collision is transmitted to the water level / vibration sensor 12, so that this can be detected. And since there is no blind spot like the detection by the tank shake sensor 15, a reliable collision detection is possible. And the tank shake sensor 15 can also be abbreviate | omitted. Further, when the tank shake sensor 15 and the water level / vibration sensor 12 are used in combination, it is possible to more reliably detect a collision and improve safety.
[0082]
The collision between the outer tub 4 and the outer frame 1 can be detected by inputting the output signal of the vibration sensor circuit 17 shown in FIG. 12 to the microcomputer 35 and comparing it with a predetermined threshold value.
[0083]
Next, the control for detecting the vibration of the outer tub 4 during the dehydration process and limiting the final dehydration speed will be described.
[0084]
FIG. 13 is a characteristic diagram showing the relationship between the vibration amplitude of the upper part of the outer tub 4 and the outer frame 1 and the upper unbalance amount. The upper unbalance amount is obtained by replacing the cloth offset amount with an equivalent mass unbalance (gram) installed in the upper part of the washing tub. The amount of unbalance and the vibration amplitude of the outer tub 4 and the outer frame 1 are in a proportional relationship.
[0085]
FIG. 14 is a characteristic diagram showing the relationship between the output signal (induced voltage) of the vibration sensor circuit 17 and the upper vibration amplitude of the outer tub 4. FIG. 15 shows the relationship between the output signal of the vibration sensor circuit 17 and the upper unbalance amount. FIG. These are experimental results at the time of steady dehydration (washing bath rotation speed 900 rpm) in this embodiment.
[0086]
The vibration amplitude of the outer tub 4 and the output signal of the water level / vibration sensor 12 installed in the outer frame 1 are in a proportional relationship, and the vibration amplitude of the outer tub 4 is indirectly detected based on the output signal of the water level / vibration sensor 12. You can see that you can. 14 shows data at 900 rpm (dehydration rotation frequency of about 16 Hz) at the time of steady dehydration. As described above, at 600 rpm (10 Hz: 1/2 natural frequency of the vibrator), as shown in FIG. The output signal of the water level / vibration sensor 12 is further increased.
[0087]
Limitation of spin speed
In the dehydration process, the inner tub 6 serving as a washing and dewatering tub is subjected to a rotational load in response to a partial load generated from a side of the laundry, and the outer tub 4 containing the same vibrates. This uneven load causes a moment force on the rotating shaft of the inner tub 6 (the output shaft 9d of the driving device 9), and a large moment load is applied to the connecting portion between the inner tub 6 and the rotating shaft. For this reason, when the side of the laundry is large, that is, the rotational vibration of the inner tub 6 is large and the vibration of the outer tub 4 is large, the connecting portion between the inner tub 6 and the rotating shaft is damaged by the moment load. It can be dangerous. Since this moment force is proportional to the square of the spin speed, it is desirable to limit (suppress) the spin speed when the vibration is large. The maximum dewatering rotation speed allowed when there is almost no cloth offset is defined by the safe design values of the inner tub 6 and the rotating shaft connecting portion.
[0088]
Simultaneously with the start of dehydration, the microcomputer 35 monitors the dehydration speed every predetermined time, for example, every 500 ms, based on the output signal of the hall sensor 9c. When the dehydration speed reaches a predetermined value, for example, 580 rpm immediately before 600 rpm (10 Hz: 1/2 natural frequency of the vibrator), the output signal of the vibration sensor circuit 17 having no integration circuit is output for a certain period of time. For example, every 10 ms, and when 620 rpm is reached, the monitoring is terminated, and the peak value is calculated from the 10 ms sample value. From this value, the vibration of the outer tub 4, that is, the unbalance amount that causes the vibration is detected (see the relationship between FIGS. 14 and 15).
[0089]
The number of rotations of 600 rpm is 10 Hz in frequency, which is close to the natural vibration frequency of the outer frame 1 described above. As a result, the vibration frequency (10 Hz) of the outer tub 4 serving as the excitation source matches the natural vibration frequency of the outer frame 1, and the vibration of the outer frame 1 becomes larger than at other frequencies (number of rotations). That is, vibration can be detected with high sensitivity. Further, the natural frequency of the vibrator 12k of the water level / vibration sensor 12 is adjusted to be equal to or higher than the maximum dehydration rotation frequency and the 1 / N (N is an integer of 2 or more) frequency matches the natural frequency of the outer frame 1. If so, the sensitivity can be further increased. As described above, in general, the actual vibrator 12k has non-linearity in the component parts, processing, and mounting methods, and has a frequency N times or 1 / N (N is an integer of 2 or more) times the natural frequency. However, this is because it has some resonance characteristics (more easily vibrates with respect to other frequencies). Specifically, if the natural frequency of the vibrator 12k is designed at 20 Hz (rotation speed 1200 rpm), the ½ frequency becomes 10 Hz, which can be matched with the natural vibration frequency of the outer frame 1, and the sensitivity is further increased. Can do.
[0090]
The relationship between the equivalent unbalance amount due to the cloth piece and the sensor output voltage (FIG. 15) is approximated by an approximate line in advance, and the inclination, intercept, etc. of this line are stored in the microcomputer 35. It may be stored as table data. Further, the equivalent unbalance amount and the safe final dewatering rotation speed, that is, a value for suppressing the dewatering rotation speed below this value is stored as a table value. The output signal of the water level / vibration sensor 12 at 600 rpm is read, and the safe final dewatering speed is set from this table.
[0091]
Thereafter, acceleration is performed to the set safe final dewatering speed, and dehydration is performed for a predetermined time after reaching the safe final dewatering speed (steady dewatering). Thereby, it becomes possible to avoid the fastening part breakage which arises from the one side of a laundry, etc., and can implement | achieve a safe washing machine. Naturally, as will be described below, the dewatering performance decreases when the dewatering speed is low. However, it is only necessary to maintain the performance by adjusting (longening) the dewatering time.
[0092]
Noise reduction
Further, as shown in FIG. 11, the water level / vibration sensor 12 can also detect the vibration amplitude value at the time of steady dehydration. When this value is large, that is, when the cloth piece side is large, it is constant. It is also possible to perform operation control that always reduces the rotational speed to suppress noise. Hereinafter, rotation control of the washing tub 6 for suppressing the noise level to a certain level or lower during dehydration will be described.
[0093]
FIG. 16 shows the relationship between the average value of the noise level and the output voltage of the vibration sensor circuit 17 in the dehydration steady state (about 900 rpm) when a 5 kg JIS test cloth is washed many times in a washing machine with a rated capacity of 7 kg. FIG. The cross-correlation coefficient between the noise level and the output voltage is as high as 0.91.
[0094]
FIG. 17 is a characteristic diagram showing the relationship between the number of rotations of the washing tub 6 and the noise level, and is a case of JIS test cloth 5 kg. The rotation speed of the washing tub 6 at the time of steady dehydration is 700 rpm or more. In this rotation speed range, the noise level decreases by about 3 dB every time the rotation speed is decreased by 100 rpm.
[0095]
FIG. 18 is a characteristic diagram showing the relationship between the spin speed and the spin rate that is an indicator of the spin performance.
[0096]
Observing FIG. 16, it can be seen that the output signal of the vibration sensor circuit 17 and the noise level are proportional. Referring to FIG. 17, it can be seen that the dehydration speed can be reduced in order to reduce noise. However, referring to FIG. 18, it can be seen that the dewatering performance decreases if the dewatering speed is decreased. Therefore, if the cloth piece is large and the noise is high due to vibration caused by the cloth piece, the noise can be reduced while maintaining the dewatering performance by reducing the dehydration speed and extending the dehydration time. it can.
[0097]
The relationship between the noise level and the output voltage (see FIG. 16) is approximated by an approximate line in advance, and the inclination, intercept, etc. of the line are stored in the microcomputer 35. Further, a value for suppressing the noise level at the time of dehydration below this value is set as the upper limit threshold value of the noise level. For example, the threshold value L1 = 47 dB. Then, an output voltage corresponding to L1 is obtained on the approximate line, and these are set as the output voltage threshold value V1.
[0098]
Next, the rotation control method of the washing tub 6 at the time of dehydration will be specifically described. The microcomputer 35 drives the DC brushless motor 9a by controlling the PWM inverter circuit 39 so that the washing tub 6 rotates at the upper limit rotational speed r1 = maximum rotational speed rmax (for example, 1000 rpm). Then, the output voltage Vu of the vibration sensor circuit 17 is acquired every 500 ms, for example, and compared with the threshold value V1. Based on the result, the upper limit rotational speed r1 of the washing tub 6 is set. However, at the time of low-speed rotation immediately after the start of dehydration, Vu becomes a large value because the outer tub 4 swings to a large amplitude due to the resonance phenomenon. For this reason, after the rotation speed of the washing tub 6 exceeds a certain value, the microcomputer 35 is caused to perform the comparison. This is the same as the method described in the collision detection described above, and after a certain time after exceeding the rotation speeds of the primary and secondary resonances, that is, after the time when the vibration amplitude becomes substantially constant in FIG. At this time, the microcomputer 35 compares Vu and V1, and if Vu> V1, sets the upper limit number of rotations r1 according to ΔVu = Vu−V1. If Vu ≦ V1, r1 = maximum rotational speed rmax (for example, 1000 rpm). That is, the driving is continued as it is. Finally, the dehydration process is performed for a predetermined time T at the maximum rotation speed rmax.
[0099]
If Vu> V1, the upper limit rotational speed r1 is reduced according to ΔVu = Vu−V1. The upper limit rotational speed r1 and ΔVu have a linear relationship, and r1 = rmax−c1 · ΔVu. The coefficient c1 is determined from an approximate expression of the relationship between the noise level and the output voltage of the vibration sensor circuit 17 and a relational expression between the noise level and the rotational speed. After determining the upper limit rotational speed r1, the microcomputer 35 controls the PWM inverter circuit 39 to reset the DC brushless motor 9a to rotate at the upper limit rotational speed r1. As a result, control is performed so as to rotate at the upper limit rotational speed r1 (for example, 800 rpm). In this case, the dehydration time is extended beyond the predetermined time T. This extended time is performed by storing the relationship between the dehydration rate and time shown in FIG. 18 in advance as table data using the dehydration speed as a parameter.
[0100]
Collision prevention in the washing process
The outer tub 4 vibrates also in the washing process. However, the rotational speed of the rotary blade 7 is about 1/10 smaller than the rotational speed of the washing tub at the time of dehydration, and vibration is unlikely to occur because a large amount of washing water (about 60 L) is contained. However, not all. In particular, as shown in FIG. 8, the repetitive repetition period near the primary resonance frequency, for example, normal rotation at 0.2 second 150 rpm, 0.2 second rotation pause, 0.2 second rotation at 150 rpm, 0.2 second rotation pause. When the washing operation is performed, the laundry is entangled in the shape of a bun and the excitation force is increased, and the outer tub 4 vibrates and collides with the outer frame 1 when the cycle operation is close to the primary resonance frequency. There is. The operation control for preventing this will be described.
[0101]
In the washing process, the water level (water amount) and the vibration of the outer tub 4 are detected at the same time using the water level / vibration sensor 12 to control the rotation speed or rotation reversal cycle of the rotary blade 7.
[0102]
The microcomputer 35 detects the vibration of the outer tub 4 based on the output signal of the vibration sensor circuit 17, and shifts the primary resonance frequency of the system from the excitation source frequency when a predetermined threshold value is exceeded. The water level is monitored with reference to the output signal of the water level sensor circuit 16, the water supply electromagnetic valve 27 is controlled while monitoring the vibration with reference to the output signal of the vibration sensor circuit 17, and the washing water is supplied, or the electromagnetic wave is discharged. The valve valve 10 is controlled to drain the washing water and adjust the amount of water (mass) in the outer tub 4. Alternatively, the rotation speed or rotation reversal period of the rotor blade 7 is changed in order to shift the excitation source frequency from the primary resonance frequency of the system while monitoring vibration by referring to the output signal to the vibration sensor circuit 17.
[0103]
In the above, the present invention has been described by way of an example of a so-called vertical fully automatic washing machine in which the rotation axis of a normal washing and dewatering tub is vertical, but is not limited thereto. It is apparent that the present invention can be applied to a so-called drum type washing machine in which the rotation axis of the washing and dewatering tub is horizontal.
[0104]
In addition, process abnormalities (large vibration during dehydration, collisions, etc.) detected using the water level / vibration sensor of the present invention are stored in the EEPROM 40 and transmitted later to the outside of the washing machine for use in service operations. You can also. For example, the contents and number of times of the above-mentioned process abnormality are stored, and this is automatically and periodically transmitted to a store or a service center of a manufacturing company via the Internet or the like, and the center or the like transmits this together with customer information. Remember and accumulate. And, for customers whose process abnormalities have reached a predetermined number of times or more, it is possible to carry out service work such as pre-failure prevention diagnosis (such as whether there is a problem with the washing machine installation method, etc.) it can.
[0105]
【The invention's effect】
  According to the present invention, it is possible to realize a water level / vibration sensor suitable for detecting the water level and vibration independently and simultaneously with a simple configuration. Based on the detection signal, the vibration of the outer tub and the vibration sensor By detecting the collision and performing optimum control, it is possible to reduce the generation of vibration noise during washing and dehydration.Specifically, in the water level / vibration sensor, one coil is shared by the water level detection means and the vibration detection means, the water level detection is performed based on a change in the inductance value of the coil, and the vibration detection is performed on the induced voltage of the coil. A simple configuration is realized by performing based on this.
[0106]
Moreover, the reliability of a washing machine can be improved and high dehydration performance can be obtained.
[Brief description of the drawings]
FIG. 1 is an external view of a fully automatic washing machine showing an embodiment of the present invention.
FIG. 2 is a vertical side view of the fully automatic washing machine shown in FIG.
FIG. 3 is a plan view showing a component arrangement state on a front operation box in the fully automatic washing machine shown in FIG. 1;
4 shows a water level / vibration sensor in the fully automatic washing machine shown in FIG. 1, wherein (a) is a top view and (b) is a longitudinal side view. FIG.
FIG. 5 is an electric block diagram of a control unit of the fully automatic washing machine shown in FIG. 1;
6 is a circuit diagram showing an internal configuration of a water level sensor circuit and a vibration sensor circuit in the control unit shown in FIG. 5;
7 is a characteristic diagram showing the relationship between the oscillation frequency and the water level of the water level sensor circuit shown in FIG. 6. FIG.
FIG. 8 is a circuit diagram showing a modification of the vibration sensor circuit shown in FIG. 6;
FIG. 9 is a frequency output characteristic diagram of a water level / vibration sensor according to an embodiment of the present invention.
FIG. 10 is a vibration output characteristic diagram of the water level / vibration sensor according to the embodiment of the present invention.
FIG. 11 is a characteristic diagram showing the relationship between the vibration amplitude of the outer tub and the outer frame and the output signal of the water level / vibration sensor and the dehydration rotation frequency in the embodiment of the present invention.
FIG. 12 is a characteristic diagram showing the vibration of the outer tub and the outer frame and the output signal of the water level / vibration sensor at the start of dehydration in the embodiment of the present invention.
FIG. 13 is a characteristic diagram showing the relationship between the vibration amplitude of the outer tank and the outer frame and the upper unbalance amount of the outer tank in the embodiment of the present invention.
FIG. 14 is a characteristic diagram showing the relationship between the output signal of the water level / vibration sensor and the upper vibration amplitude of the outer tub in the embodiment of the present invention.
FIG. 15 is a characteristic diagram showing the relationship between the output signal of the water level / vibration sensor and the upper unbalance amount of the outer tub in the embodiment of the present invention.
FIG. 16 is a characteristic diagram showing the relationship between the output voltage of the vibration sensor circuit and the noise level in the embodiment of the present invention.
FIG. 17 is a characteristic diagram showing the relationship between the relative noise level and the dehydration speed in the embodiment of the present invention.
FIG. 18 is a characteristic diagram showing the relationship between the dehydration rate and the dehydration time in the embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Outer frame, 2 ... Top cover, 2d ... Front operation box, 4 ... Outer tub, 5a ... Hanging rod, 6 ... Washing and dehydration tub (washing tub, inner tub), 12 ... Water level and vibration sensor, 12a ... Rubber film, 12c ... ferrite core, 12e ... coil, 12g ... capacitor, 12i ... leaf spring, 12j ... magnet, 12k ... vibrator, 16 ... water level sensor circuit, 17 ... vibration sensor circuit.

Claims (7)

An outer frame, an outer tub that is a water receiving tank suspended inside the outer frame, an inner tub that is a washing and dewatering tub that rotates in the outer tub, and water pressure stored in the outer tub In a washing machine comprising a water level detection means for detecting the water level in the outer tub from a change in inductance value of a coil in which a magnetic material is inserted in proportion, and a control means for controlling washing and dehydration,
A vibrator configured to place a magnet supported on the water level detection means by a spring in the vicinity of the outer periphery of the coil of the water level detection means so that a magnetic flux generated from the magnet is linked to the coil ; vibration detecting means for detecting the vibration of the outer tub based on the induction voltage induced in the coil by the change in this by the vibration of the vibrator Ri generated from the magnet interlinked to the coil magnetic flux provided,
The washing machine is characterized in that the control means controls washing and dehydrating processes with reference to output signals of the water level detecting means and the vibration detecting means.   The washing machine according to claim 1, wherein the water level detection means is fixed to the outer frame.   The washing machine according to claim 1 or 2, wherein a natural vibration frequency of the vibrator is set to be larger than a maximum rotation frequency of the inner tub.   4. The washing machine according to claim 1, wherein 1 / N (N is an integer of 2 or more) of the natural vibration frequency of the vibrator is substantially matched with the natural vibration frequency of the outer frame.   5. The washing machine according to claim 1, wherein 1 / N (N is an integer of 2 or more) of the natural vibration frequency of the vibrator is set as a vibration detection target frequency of the outer tub.   6. The washing machine according to claim 1, wherein the vibration detecting means detects vibration based on a collision between the outer tub and the outer frame.   7. The washing machine according to claim 1, wherein the control unit sets a maximum dehydrating rotation speed in accordance with the vibration of the outer tub detected by the vibration detection unit.

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