JP2009240548A - Washing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a washing machine having a cloth amount detecting means for precisely detecting an amount of cloth in a drum. <P>SOLUTION: The washing machine includes a motor 7 for performing rotation drive of a drum, a rotational frequency detector 14 for detecting the rotational frequency of the motor 7, and a control unit 31 for controlling rotations of the motor 7 on the basis of a detection output of the rotational frequency detector 14. The control unit 31 accelerates rotation of the drum by prescribed acceleration torque by the motor 7 after water is contained in the cloth by pouring water, controls a first detection step of measuring a time t1 by which the rotational frequency increases by ΔN1, a second detection step of decelerating the rotation of the drum by prescribed deceleration torque by the motor after the first detection step and measuring a time t2 by which the rotational frequency decreases by ΔN2, and detects the amount of cloth on the basis of angular acceleration α1 when accelerated and angular acceleration α2 when decelerated obtained, so that unevenness of friction torque of a drum rotational axis is offset regardless of materials of cloth and the way of charging the cloth and the amount of cloth is detected precisely with a simple structure. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a washing machine having a cloth amount sensor for detecting a cloth amount that is the amount of laundry put in a drum.

  An example of the structure of a conventional drum type washing machine is shown in FIG. In the washing machine main body 1, a water tank 2 is supported in a suspended state by a suspension structure (not shown) having a vibration isolation structure. In the water tank 2, a drum 3 formed in a bottomed cylindrical shape is rotatably supported with its axial direction inclined downward from the front side to the back side. On the front side of the aquarium 2 is formed a clothing doorway 4 leading to the opening end of the drum 3, and by opening and closing the door 5 that closes the opening provided in the upward inclined surface on the front side of the washing machine body 1 so as to be openable and closable. The laundry can be taken in and out of the drum 3 through the clothing entrance 4.

  The drum 3 has a large number of through holes 6 communicating with the water tank 2 on its peripheral surface, and is provided with stirring protrusions (not shown) for stirring clothes at a plurality of positions on the inner peripheral surface. The drum 3 is rotationally driven in the forward and reverse directions by a motor 7 attached to the back side of the water tank 2. In addition, a water injection pipe 8 and a drain pipe 9 are connected to the water tank 2 to perform water injection and drainage into the water tank 2 by controlling a water injection valve and a water discharge valve (not shown).

  When the door 5 is opened, laundry and detergent are put into the drum 3, and the operation is started by an operation on the operation panel 10 provided on the front surface of the washing machine body 1, for example, a water injection conduit is provided in the water tank 2. A predetermined amount of water is injected from 8 and the drum 3 is rotationally driven by the motor 7 to start the washing process. By the rotation of the drum 3, the laundry accommodated in the drum 3 is lifted in the rotation direction by the stirring protrusion 15 provided on the inner peripheral wall of the drum 3, and the stirring operation of dropping from the lifted appropriate height position is repeated. As a result, the laundry has the effect of tapping and washing. After the required washing time, the dirty washing liquid is discharged from the drain pipe 9 and the washing liquid contained in the laundry is dehydrated by a dehydrating operation of rotating the drum 3 at a high speed. The rinsing process is performed by pouring water from 8. Also in this rinsing process, the laundry stored in the drum 3 is repeatedly lifted by the stirring protrusion 15 (not shown) by the rotation of the drum 3 and dropped to repeat the rinsing.

  In addition, on the back surface of the motor 7, a rotation detection unit 14 including a position detection element that detects the position of the rotor (rotor) of the motor is provided in order to detect the rotation state.

  The drum-type washing machine has a function of drying laundry stored in the drum 3, and the air in the water tank 2 is exhausted and dehumidified by the circulation air passage 11 to be dried by heating. Air is blown again into the water tank 2 by the blower fan 12.

  In the drum-type washing machine having the above-described configuration, a function of detecting the amount of clothes such as clothes put in the drum 3 and automatically determining the washing time according to the amount of cloth is added. Is generally (see, for example, Patent Document 1). An example of a method for detecting the amount of cloth will be described below with reference to FIGS. 9 and 10.

  The cloth amount is detected by a control circuit (not shown) having a function of controlling the motor 7 for driving the drum 3 to rotate.

When washing is started, first, the control circuit starts the motor 7 and a detection output is input from the rotation detection unit 14. The detection frequency of the rotation detector 14 changes linearly in proportion to the rotation of the motor 7. That is, the control circuit increases the average voltage of the power supply voltage of the motor 7 by means of phase control when the input frequency from the rotation detector 14 is small, and decreases the average voltage when the frequency increases.

  In the cloth amount detection process, while performing rotation control, the average voltage applied to the motor 7 is gradually increased inside the control circuit to shift to high speed rotation so that the clothes are uniformly attached to the inner wall of the drum 3 by centrifugal force. To. In this state, the rotation of the motor 7 is stopped after continuing the rotation for a predetermined time. Thereby, the inertial rotation of the drum 3 is in a state where the motor 7 is rotated. At this time, as shown in the diagram of FIG. 9, the rotation detection unit 14 converts the inertial rotational force of the drum 3 to gradually decrease due to the friction torque and stops the rotation, and outputs the result.

  In FIG. 10, the horizontal axis indicates time, and the vertical axis indicates the number of rotations of the drive motor (motor). The time from the energization stop point E to the stop of the drum 3 is long when the amount of cloth is large, and the amount of cloth is When there are few, it is short. The cloth amount is detected by utilizing the fact that the difference in time required for the stop is proportional to the cloth amount.

  Here, when the weight of the cloth is m, the average radius of the cloth distributed on the inner periphery of the drum 3 is r, and the inertia moment of the drum 3 or the motor 7 is Jd, the inertia moment J of the rotating system including the cloth is expressed by the equation (1 ).

J = Jd + mr ² (1)
Further, assuming that the generated torque of the motor 7 is T, the friction torque of the drum and the rotating shaft is Tb, and the angular acceleration of the drum 3 is α, these relationships are expressed by Expression (2).

T = Jα + Tb (2)
Since the angular acceleration α is expressed by the equation (3) as a function of the angular velocity ω and the time t, as shown in the equation (4), if the average radius r of the cloth is constant, the rotation depends on the weight m of the cloth. The number or angular velocity ω changes.

α = dω / dt (3)
dω / dt = (T−Tb) / (Jd + mr ² ) (4)
From the above equation (4), it can be seen that dω / dt, that is, the change in the rotational speed, is inversely proportional to the cloth amount m.

That is, the cloth amount can be determined by stopping energization of the motor 7 to inertially rotate the drum 3 and measuring the change in the number of rotations in a certain time interval until the drum 3 stops.
JP-A-5-168786

  When using the above conventional cloth amount detection method, the inertial rotational force of the drum gradually decreases due to the friction torque, and the proportional relationship between the time until the drum stops and the cloth amount is obtained in advance by experiments, The obtained measurement value is applied to all washing machines of the same model.

  However, as can be seen from Equation (4), the proportional relationship between the time until the drum stops and the amount of cloth is not constant due to the variation in the friction torque Tb of the drum rotation shaft, and the numerical value varies depending on each washing machine. Have For this reason, there is a problem that the conventional cloth amount detection method has variations and the detection accuracy is limited.

  Further, in the conventional cloth amount detection method, the rotation of the drum is temporarily raised regardless of the state of the clothes, so that the laundry stored in the drum 3 is affected by the bias (unbalance distribution), and the washing tub. Vibrates greatly, and the washing tub collides with the washing machine main body and makes an abnormal sound.

  In addition, the average radius r may vary greatly even if the weight is the same due to the difference in the material and state of the cloth. For example, if the cloth is dry and bulky, the cloth having the same state and weight and low bulk Since r becomes smaller than that, the moment of inertia J becomes small, and as a result, the amount of cloth may be detected small.

  The present invention solves the above-described conventional problems, and can detect the amount of cloth fed into the drum with a simple configuration and with a simple configuration, while suppressing the influence of variation in the friction torque of the drum rotation shaft. It is an object of the present invention to provide a washing machine having a means and a washing machine having a stable cloth amount detecting means that eliminates the influence of clothing bias and differences in material and state.

  In order to solve the above-described conventional problems, a washing machine of the present invention includes a drum that has a rotation center axis in a horizontal direction or an inclination direction, accommodates laundry, and performs a rotational motion, and water injection that injects water into the drum Means, a water tub enclosing the drum rotatably and elastically supported in the washing machine body, a motor for rotating the drum, a rotation speed detecting device for detecting the rotation speed of the motor, and the rotation And a controller that controls the rotation of the motor based on the detection output of the number detector, and the controller causes the motor to generate a predetermined acceleration torque after pouring water into the drum by the water pouring means. A first detection step of accelerating the rotation of the drum and measuring an acceleration angular acceleration α1 while the rotation number increases from a predetermined rotation number N1 to N2, and after the first detection step, Speeding tor And a second detection step of measuring the deceleration angular acceleration α2 while the rotational speed decreases from a predetermined rotational speed N3 to N4. The cloth amount is detected based on the acceleration α1 and the angular acceleration α2 during deceleration.

  As a result, since the amount of cloth is measured using both the speed of rising and lowering of the drum rotation, the friction torque variation of the drum rotation shaft is offset, and the influence of the variation can be suppressed. The amount of cloth can be accurately detected with a simple configuration.

  In addition, by adding water to the drum before detecting the amount of cloth and adding moisture to the cloth in the drum, it is possible to reduce the difference in bulk depending on the material and state of the cloth, and the accuracy with a simple configuration The amount of cloth can be detected well.

  The washing machine of the present invention can obtain the cloth amount detecting means that can accurately detect the friction torque of the drum rotating shaft with a simple configuration while suppressing the influence of variations of individual devices.

A first aspect of the present invention is a drum having a rotation center axis in a horizontal direction or an inclination direction, accommodating a laundry and performing a rotational movement, a water injection means for injecting water into the drum, and a drum including the drum rotatably. A water tub elastically supported in the washing machine body, a motor for rotationally driving the drum, a rotational speed detection device for detecting the rotational speed of the motor, and the motor based on the detection output of the rotational speed detection device A controller for controlling the rotation of the drum, the controller irrigates the drum with water injection means, and then accelerates the rotation of the drum by generating a predetermined acceleration torque in the motor. The first detection step of measuring the acceleration angular acceleration α1 while the rotation speed increases from the rotation speed N1 to N2, and the drum generates a predetermined deceleration torque after the first detection process. Times , And a second detection step of measuring the angular acceleration α2 during deceleration while the rotational speed decreases from a predetermined rotational speed N3 to N4, and the angular acceleration α1 during acceleration and the angular acceleration α2 during deceleration Therefore, since the cloth amount is measured by using both the drum rotation speed and the descent speed, the variation in the friction torque of the drum rotation shaft is offset and the influence of the variation is detected. In addition, it is possible to reduce the difference in bulk depending on the material and state of the cloth by injecting water into the drum before detecting the amount of cloth and adding moisture to the cloth in the drum. Therefore, it is possible to accurately detect the amount of cloth with a simple configuration.

  The second aspect of the invention is particularly characterized in that the control unit of the first aspect of the invention is provided with a time measuring means for measuring time, and the water injection means is controlled so as to stop the water injection when a predetermined time elapses after the start of water injection. The amount of water can be stably controlled, and the amount of cloth can be detected accurately with a simple configuration.

  According to a third aspect of the present invention, the controller of the first or second aspect of the invention is provided with a water level detecting means for detecting the water level, and water injection is stopped so as to stop water injection when it is detected that a predetermined water level has been exceeded after the start of water injection. By controlling the means, the amount of water injection can be stably controlled, and the amount of cloth can be detected accurately with a simple configuration.

  In the fourth aspect of the invention, the control unit of the first to third aspects of the invention is provided with a flow rate detection means for detecting the flow rate of water, and after the start of water injection, it is detected that the total amount of water injection has exceeded a predetermined amount. Then, by controlling the water injection means to stop the water injection, the amount of water injection can be stably controlled, and the amount of cloth can be detected accurately with a simple configuration.

  In the fifth aspect of the invention, in particular, the control unit of the first to fourth aspects of the invention controls the drum to rotate during the water injection operation, so that the injected water is uniformly contained in the cloth, and the accuracy is high. The amount of cloth can be detected.

  In particular, the sixth invention is the first to fifth inventions, comprising a water intake at the lower part of the water tank and a water supply port at the upper part of the water tank, and a circulation path formed by connecting circulation means therebetween, After the start of water injection, the part circulates the water injected in the circulation path by the circulation means, so that the injected water is more effectively included in the clothing, and the amount of cloth can be detected accurately. it can.

  In the seventh aspect of the invention, in particular, the control unit of the sixth aspect of the invention is provided with a time measuring means for measuring time, and the circulation means is controlled so as to stop the circulation when a predetermined time has elapsed from the start of circulation. Since the amount is stably controlled, the amount of cloth can be accurately detected.

  In the eighth aspect of the invention, in particular, the control unit of the sixth or seventh aspect of the invention is provided with a water level detecting means for detecting the water level, and after the start of circulation, when it is detected that the water level has fallen below a predetermined level, the circulation is stopped. By controlling the circulation means, the circulation amount is stably controlled, and the cloth amount can be detected with high accuracy.

  In particular, the ninth aspect of the invention comprises the control unit of the sixth to eighth aspects of the invention, comprising flow rate detection means for detecting the flow rate of water, and detecting that the circulation amount has fallen below a predetermined value after the start of circulation. By controlling the circulation means to stop the circulation, the circulation amount is stably controlled, and the cloth amount can be detected with high accuracy.

In the tenth aspect of the invention, in particular, the control unit of the sixth to ninth aspects of the invention controls the drum to rotate during the circulation operation, so that the circulated water is uniformly contained in the cloth, and the accuracy is high. The amount of cloth can be detected.

  In the eleventh aspect of the invention, in particular, the control unit of the sixth to tenth aspects of the invention detects the amount of cloth after the operation of the circulating means stops, so that only the drum is driven during detection of the amount of cloth. Therefore, the amount of cloth can be detected with high accuracy.

  In the twelfth invention, at least the first detection step and the second detection step are performed by controlling the voltage applied to the motor or controlling the energization current by the control unit of the first to eleventh inventions. In the middle, the acceleration torque and the deceleration torque are controlled to be constant at their respective predetermined values, so that the acceleration torque and the deceleration torque are kept constant, so that the left side of the above equation (2) is constant. Therefore, it is possible to detect the cloth amount with high accuracy without complicatedly considering the influence of fluctuations in the acceleration torque and the deceleration torque.

  In a thirteenth aspect of the invention, in particular, in the control unit of the first to twelfth aspects of the invention, in the first detection step and the second detection step, the q-axis current supplied to the motor is the first detection step and By controlling the acceleration torque and deceleration torque of the motor so as to be a predetermined constant value in each of the second detection steps, the q-axis current related to the magnet torque, which is the main component of the torque in the motor, is increased. By making it constant, the acceleration torque and the deceleration torque can be controlled to be substantially constant, so that the cloth amount can be detected with high accuracy.

  In the fourteenth aspect of the invention, in particular, the control unit of the first to thirteenth aspects of the control is such that the d-axis current supplied to the motor becomes substantially zero during the first detection step and the second detection step. As a result, the generated torque in the motor is only the magnet torque, and the acceleration torque and the deceleration torque are controlled only by the q-axis current, making it easy to control. Is possible.

  In the fifteenth aspect of the invention, the control unit of the first to fourteenth aspects of the invention measures the maximum rotation speed and the minimum rotation speed of the drum in the predetermined rotation angle section in the first detection step, and the maximum rotation speed and the minimum rotation speed. If the difference is equal to or larger than a predetermined value, the rotation of the drum is controlled to stop, so that the distribution of the cloth in the drum becomes uneven, and the vibration of the drum is lower than the predetermined value. Even when it becomes larger, the drum can be safely stopped.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Components having the same configurations as those of the conventional example are denoted by the same reference numerals, and detailed description thereof is omitted. In addition, this invention is not limited by this embodiment.

(Embodiment 1)
1 is a cross-sectional view showing a schematic configuration of a drum-type washing machine according to Embodiment 1 of the present invention.

  In FIG. 1, the time measuring means 16a measures the elapsed time from the start of water injection. The water level detection means 16b detects the water level in the water tank 2. The flow rate detection means 16 c detects the flow rate of water flowing into the water tank 2.

  In detecting the amount of cloth in the drum 3, the moment of inertia J including the drum 3 and the cloth inside the drum is expressed by the inertia moment Jd of the motor, the weight m of the cloth, It is represented by an average radius r distributed in the drum 3.

Among these, the moment of inertia Jd of the motor 7 does not change greatly depending on the value specific to the motor 7, and the weight of the cloth does not depend on the material of the cloth or the feeding method. And changes greatly depending on the input method.

  That is, even when cloths of the same weight are input, cloths with high density and high flexibility are distributed in the vicinity of the inner periphery of the drum 3, so that the value of r is close to the inner diameter rd of the drum 3. On the contrary, even if cloth with low density or cloth that is stiff and firm is inserted, the value of r is close to rd / 2 because the cloth is averagely distributed in the space in the drum 3.

  One means for reducing the difference between the two is to include water in the cloth. When water is included in the cloth, the flexibility of the fibers constituting the cloth increases, so that the cloth is likely to be distributed in the vicinity of the inner periphery of the drum 3. In addition, since the air layer formed inside the cloth is replaced with water, the difference in density between the cloths is also reduced. As a result, the average radius r is equal to the inner diameter of the drum 3 even if the material and the charging method of the cloth are different. The value of the moment of inertia J can be a function having only the cloth weight m as a variable.

  Specifically, when a cloth is put into the drum 3 and the operation is started by an operation on the operation panel 10, first, a predetermined amount of water is injected into the water tank 2 from the water injection conduit 8, and then the amount of cloth is detected. It will be transferred to the process.

  At this time, since the weight of the injected water also affects the moment of inertia J, it is necessary to determine the amount within a certain error range, but as a simple method, water injection is started using the time measuring means 16a. This is a method of stopping water injection after a predetermined time has elapsed.

  Further, as a method for directly detecting the amount of water, the water level detection means 16b is used to detect the water level in the water tank 2, and water injection is stopped when a predetermined water level is exceeded, or the flow rate detection means 16c is used. For example, a method of directly detecting the amount of water to be injected and stopping water injection when a predetermined amount is exceeded may be mentioned.

  In general, the latter has higher accuracy but higher cost, so a method may be selected or combined based on required accuracy and cost.

  In addition, if the drum 3 is rotated during the water injection operation, water can be included on the average by the cloth in the drum 3, so that a more preferable result can be obtained.

  FIG. 2 shows a schematic configuration of a control device for controlling the operation of the drum type washing machine in the first embodiment of the present invention.

  In the control device shown in FIG. 2, the AC power of the commercial power supply 20 is rectified by the rectifier 21 and the inverter circuit 24 uses the DC power smoothed by the smoothing circuit including the choke coil 22 and the smoothing capacitor 23 as the driving power. 7 is driven to rotate. Further, the rotation of the motor 7 is controlled based on the driving instruction input from the input setting unit 25 and the monitoring information of the driving state detected by each detecting means (not shown), and the water supply valve 27 is controlled by the load driving unit 26. The operation of the drain valve 28, the blower fan 12, and the heater 29 is controlled.

The motor 7 includes a stator having three-phase windings 7a, 7b, and 7c and a rotor having a two-pole permanent magnet, and is configured as a DC brushless motor provided with three position detection elements 30a, 30b, and 30c. The rotation is controlled by a PWM control inverter circuit 24 configured by the switching elements 24a to 24f. The rotor position detection signals detected by the position detection elements 30a, 30b, and 30c are input to the control unit 31 configured by a microcomputer. Based on the rotor position detection signal, the drive circuit 32 turns on / off the switching elements 24a to 24f.
By performing PWM control of the off state, energization to the three-phase windings 7a, 7b, and 7c of the stator is controlled to rotate the rotor at a required number of revolutions.

  The control unit 31 includes a rotation speed detection unit 33 to which detection outputs of the three position detection elements 30a, 30b, and 30c are input. The rotation speed detection unit 33 detects the cycle whenever the signal state of any of the three position detection elements 30a, 30b, and 30c changes, and calculates the rotation speed of the rotor from the cycle. The detection output of the rotation speed detector 33 is supplied to the cloth amount detector 34, and the cloth amount is detected as described below based on the detected rotation speed.

  Since the detection output of the rotation speed detector 33 corresponds to the rotation speed of the drum 3, the rotation speed of the drum 3 is obtained from the detection output of the rotation speed detector 33 in the following description.

  The characteristics of the cloth amount detection method in the present embodiment will be described below with reference to FIG.

  FIG. 3 is a diagram showing the operation of detecting the amount of cloth, and shows the relationship between the time required for increasing the rotation speed of the drum 3 and the time required for decreasing the rotation speed. Time and the vertical axis represent the number of rotations.

  When the cloth amount detection is started, the acceleration torque T1 is generated by the motor 7 after the elapse of a predetermined time or when the predetermined rotation speed N1 is reached, and the rotation speed is increased by ΔN1 during the time t1 to reach the predetermined rotation speed N2. A first detection process for detecting the arrival time t1 is performed. After the end of the first detection step, the rotation speed of the drum 3 is changed from acceleration to deceleration, and then a deceleration torque T2 is generated by the motor 7 that has rotated by inertia, and a predetermined rotation speed N3 is generated during the time t2. The second detection step is performed in which the rotational speed is decreased by ΔN2 to reach a predetermined rotational speed N4.

  Here, the operation state of the first detection process will be considered.

  From equation (3), the angular acceleration α1 in the first detection step is represented by equation (5).

α1 = ΔN1 / t1 (5)
Moreover, Formula (6) is materialized from Formula (1) and (2).

T1 = α1 (Jd + mr ² ) + Tb (6)
Similarly, considering the second detection step, Equation (7) and Equation (8) are obtained when the angular acceleration in the second detection step is α2.

α2 = ΔN2 / t2 (7)
T2 = α2 (Jd + mr ² ) + Tb (8)
When the component of the friction torque Tb is eliminated from the equations (6) and (8), the equation (9) is obtained.

α1-α2 = (T1-T2) / (Jd + mr ² ) (9)
FIG. 4 is a diagram showing the relationship between the amount of cloth and the acceleration difference, the horizontal axis is the cloth amount, and the vertical axis is the acceleration difference. The above equation (9) is easily understood.

  When the average radius r, acceleration torque T1, and deceleration torque T2 in the drum inner periphery of the cloth are constant values, the equation (9) is expressed as (α1−) according to the weight m of the cloth as shown in FIG. It shows that α2) changes.

Here, α1 and α2 can be easily obtained by measuring the relationship between the number of rotations of the drum 3 and time, as shown in equations (5) and (7). Therefore, if only the relationship between the fabric weight m and the change in the angular acceleration (α1-α2) is grasped and stored as a calculation table in the fabric amount detection unit 34 of the control unit in FIG. It can be seen that the amount of cloth can be detected easily and accurately regardless of the relationship.

  FIG. 5 is a flowchart illustrating the cloth amount detection method.

  In FIG. 5, when the cloth amount detection starts (step S1), the control unit 31 drives the motor 7 to increase the rotational speed of the drum 3 from the predetermined rotational speed N1 with a predetermined torque, thereby rotating the rotational speed. Is controlled to reach a predetermined rotational speed N2 increased by ΔN1 (step S2). When the drum 3 reaches the rotation speed N2 (step S3), a time t1 required for the rotation speed to increase by ΔN1 is calculated (step S4).

  Next, a decrease in the rotational speed of the motor 7 is started (step S5). When the drum 3 reaches a predetermined rotational speed N4 from which the rotational speed has decreased by ΔN2 from the predetermined rotational speed N3 (step S6), a required time t2 required for the rotational speed to decrease by ΔN2 is calculated (step S6). S7).

  Next, the angular acceleration α1 of the first detection step and the angular acceleration α2 of the second detection step are calculated from ΔN1, t1, ΔN2, and t2 based on the equations (5) and (7), and the difference α1 between the two angular accelerations is calculated. -Α2 is obtained (step S8), and the amount of cloth is obtained based on the formula (9) from the relationship between the determination value S measured in advance and the amount of cloth (step S9).

  In order to accurately detect the amount of cloth using Expression (9), it is desirable to control the acceleration torque T1 and the deceleration torque T2 of the motor 7 to be constant.

  Although the control as described above can be realized by controlling the voltage applied to the motor 7, generally, the constant torque control of the motor can be performed by vector control as described below.

  FIG. 6 is a block diagram showing vector control in the cloth amount detection.

  In the control block diagram of FIG. 6, at least a two-phase current out of the current supplied to the motor 7 and a rotational position signal of the motor obtained by a Hall IC or the like are detected. Using these signals, the current of the motor 7 is converted into two orthogonal currents, Iq which is a torque component and Id which is a magnetic flux component. Thereafter, the converted Iq and Id are compared with the commanded Iq * and Id *, and the appropriate control gains P and I are used to control the Iq and Id of the motor 7 to be constant. Can do.

  Here, since the torque T of the motor 7 is expressed by the following equation (10), the torque T of the motor 7 can be controlled by controlling Iq (q-axis current) and Id (d-axis current).

T = P (ψa · Iq + (Ld−Lq) IqId) (10)
Here, P is the number of pole pairs of the motor 7, ψa is a flux linkage by a magnet, Ld is a d-axis inductance, and Lq is a q-axis inductance.

  In particular, ψa · Iq in equation (10) represents a magnet torque and is the main component of the torque generated by the motor. Therefore, the torque of the motor 7 can be controlled mainly by Iq (q-axis current). In addition, when Id (d-axis current) is not zero, if Ld and Lq change depending on the rotation state, an error is likely to occur when calculating the torque T when calculating the variation of the torque T or the amount of cloth.

  That is, there is a case where the torque T does not become constant even if Iq (q-axis current) and Id (d-axis current) are controlled to be constant. Therefore, Id (d-axis current) is set to zero, and Iq (q-axis current) ) Is controlled to be constant, and the torque of the motor 7 is controlled to be constant, so that the cloth amount detection calculation error can be reduced.

  In the cloth amount detection of the washing machine configured as described above, both moisture rises (first detection) and lowering speed (second detection) corners after moisture is included in the cloth. Since the amount of cloth is measured using acceleration, the difference due to the material and loading method of the cloth is reduced, and the fluctuation of the friction torque of the drum rotation shaft is offset, and the influence of the fluctuation is suppressed. High detection is possible.

(Embodiment 2)
FIG. 7 is a cross-sectional view showing a schematic configuration of the drum type washing machine in the second embodiment of the present invention.

  The configuration of the washing machine, the configuration of the control device, and the cloth amount detection method in the second embodiment are basically the same as those described in the first embodiment. The difference in the present embodiment is that, in FIG. 7, a water intake port 17 for taking out water in the water tank 2 is provided in the lower part of the water tank 2, and a water supply port 18 for supplying water taken out from the water intake port 17 to the water tank 2 again. Is provided in the upper part of the water tank 2 and serves to guide the water taken out from the water intake port 17 to the water supply port 18, and is provided with a circulation means 19 composed of, for example, a pump, and the water intake port 17, the circulation means 19, A circulation path 19a formed by connecting the water supply port 18 is configured.

  When a predetermined amount of water is poured before detecting the amount of cloth, if the cloth is thrown into only the front side of the drum 3, for example, by the cloth throwing method, the injected water is not included in the cloth, It stays in the lower part of the water tank 2 as it is.

  In order to prevent this, the staying water is supplied from the upper part of the water tank 2 through the circulation path 19a.

  Thereby, even when the water which stayed is contained in the cloth and water is not contained in the cloth by the initial water injection, a desired effect can be obtained.

  As a means for determining the end of the circulation operation, a method of ending at a predetermined time using the time measuring means 16a, a method of ending when the water level is detected below the predetermined water level using the water level detecting means 16b, and a flow rate detection Although the method of ending when the flow rate circulated using the means 16c falls below a predetermined amount can be mentioned, as in the first embodiment, the cost is generally higher in accuracy as the latter, so the required accuracy is required.・ Select methods or use them in combination based on cost.

  If the drum 3 is rotated during the circulation operation, water can be included on the average by the cloth in the drum 3, so that a more preferable result can be obtained.

  In the cloth amount detection of the washing machine configured as described above, an increase in the rotation of the drum (first detection) is performed by adding water to the cloth by pouring water, circulating the accumulated water, and supplying water again. ) And the rotational acceleration (second detection) are used to measure the amount of cloth, so the difference due to the material of the cloth and the feeding method is reduced, and the friction torque variation of the drum rotation shaft is offset. Therefore, the influence of the variation is suppressed, and highly accurate detection is possible.

(Embodiment 3)
FIG. 8 is a diagram illustrating a washing machine control method according to the third embodiment of the present invention.

  The configuration of the washing machine, the configuration of the control device, and the cloth amount detection method in the third embodiment are basically the same as those described in the first embodiment. The difference in the present embodiment is that when the number of rotations of the drum 3 is increased in order to detect the amount of cloth, the driving of the drum 3 is stopped according to the change in the number of rotations accompanying the increase in the number of rotations. This is the point where control is provided.

  FIG. 8A shows how the rotation speed of the drum 3 increases with time. The horizontal axis represents the elapsed time when the motor 7 is driven and the rotational speed of the drum 3 is increased by a predetermined torque, and the vertical axis is the rotational speed of the drum 3. As shown in the figure, the rotational speed of the drum 3 does not increase uniformly, but increases while repeating vertical movement. This is because the laundry tub vibrates due to the balance of the laundry accommodated in the drum 3. If the vibration becomes too large, the washing tub collides with the washing machine body and generates an abnormal sound.

  In the present embodiment, control for avoiding such a situation is performed. That is, the difference between the maximum rotation speed and the minimum rotation speed is detected for the rotation speed of the drum 3 in a predetermined rotation angle section while the rotation of the drum 3 is being accelerated. If the difference is greater than or equal to a predetermined value, the drum 3 is controlled to stop rotating. As the maximum rotation speed and the minimum rotation speed of the drum 3 in the predetermined rotation angle section, for example, the rotation speed is measured four times during one rotation, and the maximum rotation speed and the minimum rotation speed are obtained.

  FIG. 8B is a diagram showing the relationship between the rotation speed of the drum and the upper limit value of the difference between the maximum and minimum rotation speeds.

  As shown in FIG. 8B, an upper limit value of the difference between the maximum rotation speed and the minimum rotation speed is set based on the experiment in correspondence with the rotation speed of the drum 3, and is provided in the control unit 31 as a table. The upper limit value of the difference between the maximum number of rotations and the minimum number of rotations as shown in FIG. 8B may be set based on the allowable range of vibration obtained experimentally at each number of rotations of the drum 3.

  As described above, in the third embodiment, the balance of the laundry is poor by controlling so that the difference between the maximum rotation speed and the minimum rotation speed in the predetermined rotation angle section of the drum 3 does not exceed the upper limit value. As a result, it is possible to avoid a situation where the washing tub vibrates greatly and collides with the washing machine main body, and once it is stopped, it can be started again and detected.

  According to the present invention, it is possible to accurately detect the amount of cloth put into the drum with a simple configuration, and to perform appropriate washing time setting, detergent amount display, and appropriate time setting dehydration process. It is useful for home and commercial washing machines.

Sectional drawing which shows schematic structure of the drum type washing machine in Embodiment 1 of this invention. Circuit diagram showing the control device of the drum type washing machine The figure which shows the operation | movement of the cloth amount detection used for the drum type washing machine The figure which shows the cloth amount and acceleration difference of the cloth amount detection Flow chart showing the cloth amount detection method Block diagram showing vector control in cloth amount detection Sectional drawing which shows schematic structure of the drum type washing machine in Embodiment 2 of this invention. The figure which shows the control method of the drum type washing machine in Embodiment 3 of this invention. Sectional drawing which shows schematic structure of the conventional drum type washing machine The figure which shows the cloth amount detection method of the conventional drum type washing machine

Explanation of symbols

1 Washing machine body 2 Water tank 3 Drum 7 Motor 8 Water injection pipe (water injection means)
14 Rotation detector (Rotation speed detector)
16a Timekeeping means 16b Water level detection means 16c Flow rate detection means 17 Water intake 18 Water supply port 19 Circulation means 19a Circulation path 20 Commercial power supply 30a, 30b, 30c Position detection element 31 Control unit 32 Drive circuit 33 Rotation speed detection unit 34 Cloth amount detection unit

Claims (15)

A drum having a rotation center axis in a horizontal direction or an inclination direction, accommodating a laundry and performing a rotational movement, a water injection means for injecting water into the drum, and a drum that rotatably includes the drum in the main body of the washing machine An elastically supported water tank, a motor for rotationally driving the drum, a rotational speed detection device for detecting the rotational speed of the motor, and a control for controlling the rotation of the motor based on a detection output of the rotational speed detection device The controller is configured to accelerate the rotation of the drum by causing the motor to generate a predetermined acceleration torque after water is injected into the drum by the water injection means, and from a predetermined rotational speed N1 to N2. After the first detection step of measuring the acceleration angular acceleration α1 while the rotational speed increases, and after the first detection step, the motor is caused to generate a predetermined deceleration torque to reduce the rotation of the drum. , A second detecting step of measuring an angular acceleration at deceleration α2 while the rotational speed decreases from a constant rotational speed N3 to N4, and based on the angular acceleration at acceleration α1 and the angular acceleration at deceleration α2 A washing machine characterized by detecting the amount. 2. The washing machine according to claim 1, wherein the control unit includes a time measuring unit that measures time, and controls the water injection unit to stop water injection when a predetermined time elapses after the start of water injection. The control unit includes a water level detection unit that detects a water level, and controls the water injection unit to stop water injection when it is detected that a predetermined water level has been exceeded after the start of water injection. The washing machine described. The control unit includes a flow rate detection means for detecting the flow rate of water, and controls the water injection means to stop the water injection when detecting that the total amount of water injection exceeds a predetermined amount after the start of water injection. The washing machine according to any one of claims 1 to 3. The washing machine according to any one of claims 1 to 4, wherein the control unit controls the drum to rotate during the water pouring operation. The water tank has a water intake port at the bottom, a water supply port at the top of the water tank, and a circulation path formed by connecting a circulation means between them, and the control unit supplies the water poured in the circulation path after the start of water injection. It is made to circulate by the said circulation means, The washing machine of any one of Claims 1-5 characterized by the above-mentioned. The washing machine according to claim 6, wherein the control unit includes a time measuring unit for measuring time, and controls the circulation unit to stop the circulation when a predetermined time has elapsed from the start of the circulation. The control unit includes a water level detection unit that detects a water level, and controls the circulation unit to stop the circulation when detecting that the water level has fallen below a predetermined water level after the start of circulation. The washing machine described. The control unit includes a flow rate detection unit that detects a flow rate of water, and controls the circulation unit to stop the circulation when it is detected that the circulation amount has fallen below a predetermined value after the start of circulation. Item 9. The washing machine according to any one of Items 6 to 8. The washing machine according to any one of claims 6 to 9, wherein the control unit controls the drum to rotate during the circulation operation. The washing machine according to any one of claims 6 to 10, wherein the control unit detects the amount of cloth after the operation of the circulation unit is stopped. The control unit controls the voltage applied to the motor or the energization current, so that the acceleration torque and the deceleration torque are constant at each predetermined value at least during the first detection step and the second detection step. The washing machine according to any one of claims 1 to 11, which is controlled so as to become. In the first detection step and the second detection step, the control unit is configured so that the q-axis current supplied to the motor becomes a predetermined constant value in each of the first detection step and the second detection step. The washing machine according to claim 1, wherein an acceleration torque and a deceleration torque of the motor are controlled. The controller according to any one of claims 1 to 13, wherein the controller controls the d-axis current to be supplied to the motor to be substantially zero during the first detection step and the second detection step. Machine. The control unit measures the maximum rotation speed and the minimum rotation speed of the drum in a predetermined rotation angle section in the first detection step, and if the difference between the maximum rotation speed and the minimum rotation speed is a predetermined value or more, the drum The washing machine according to any one of claims 1 to 14, wherein the rotation drive is stopped.

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