JP4242263B2 - Washing machine - Google Patents

Description

  The present invention relates to a washing machine, and more particularly to a washing machine having a function of detecting the amount of cloth in a washing tub.

As a cloth amount detection means of a conventional washing machine, Japanese Patent Laid-Open No. 2003-210888 (Patent Document 1) obtains an inertia moment of a washing tub that contains a laundry cloth and is driven to rotate by a motor, and based on the obtained inertia moment. In the cloth amount detection method of the washing machine for detecting the cloth amount, the washing tub is accelerated by a first torque, a rotation speed R equal to or higher than a first rotation speed of the washing tub is detected, and the washing tub A rotation speed r higher than the first rotation speed and higher than the second rotation speed is detected, and a required time from the rotation speed R to the rotation speed r is measured, and the first torque, the rotation speed R, the rotation speed r, and the required time are measured. A method for detecting the amount of cloth in a washing machine is described in which the moment of inertia is obtained based on the above.
JP 2003-210888 A

  However, in Japanese Patent Application Laid-Open No. 2003-210888, since the cloth amount detection step is performed by the same process regardless of the amount of cloth in the washing tub, a detection processing time of a certain amount or more is always required. Further, since it is necessary to measure the time required from the rotational speed R to the rotational speed r, the amount of cloth cannot be detected unless at least the washing tub is rotated to the rotational speed r.

  The present invention has been made to solve such a problem, and one of the objects of the present invention is to provide a washing machine capable of shortening the cloth amount detection time.

  In order to achieve the above object, according to one aspect of the present invention, the washing machine includes a driving unit for rotating the washing tub, a driving control unit for controlling the driving unit, and an angle detection for detecting a rotation angle of the washing tub. Means, angular velocity detection means for detecting the angular velocity of the washing tub, and storage means for storing the relationship between the time required to rotate the laundry tub by a predetermined angle by changing the angular velocity of the washing tub and the amount of cloth. The time when the washing tub rotates by a predetermined angle by changing the angular velocity of the washing tub is counted, and the first cloth in the washing tub is based on the relationship between the time measured, the stored time and the amount of cloth. A first cloth amount detecting means for detecting the amount, and a moment of inertia of the washing tub detected from a state in which the washing tub has rotated beyond a predetermined angular velocity, and a second amount of cloth in the washing tub is detected from the detected moment of inertia. A second cloth amount detecting means for detecting The laundry amount sensing means has a precision below a predetermined laundry amount, before the washing tub is ready to be detected by the second laundry amount sensing means detects the first laundry amount.

  According to this invention, the washing machine has a detection accuracy when the first cloth amount detection means is equal to or less than the predetermined cloth amount, and before the washing tub is in a state where it can be detected by the second cloth amount detection means. First, the first cloth amount is detected. For this reason, when the amount of cloth in the washing tub is equal to or less than the predetermined amount of cloth, the amount of cloth can be detected by the first cloth amount detecting means. In that case, since it is not necessary to detect the amount of cloth by the second cloth amount detection means, it is possible to provide a washing machine capable of reducing the time for detecting the amount of cloth.

  Preferably, when the first cloth amount detected by the first cloth amount detector is equal to or less than a predetermined cloth amount, the second cloth amount detector is driven based on the first cloth amount without activating the second cloth amount detector. Control means for controlling the means is further provided.

  According to this invention, when the first cloth amount is equal to or less than the predetermined cloth amount, the second cloth amount detecting means is not activated and the cloth amount is determined. This eliminates the time required for the second cloth amount detection.

  Preferably, the control means activates the second cloth amount detection means when the first cloth amount detected by the first cloth amount detection means exceeds a predetermined cloth amount, and the second cloth amount detection means The driving means is controlled based on the detected second cloth amount.

  According to this invention, when the first cloth amount exceeds the predetermined cloth amount, the driving means is controlled by the second cloth amount detected by the second cloth amount detecting means. Even if the amount of cloth in the washing tub exceeds a predetermined amount of cloth, the amount of cloth can be accurately detected, so that the driving means can be controlled in accordance with the amount of cloth in the washing tub.

  Preferably, the rotation axis of the washing tub is substantially horizontal with respect to the floor surface, or is inclined so that the opening of the washing tub faces upward.

  Preferably, the drive control means drives the drive means using vector control.

  According to the present invention, the driving means is vector-controlled. Thereby, a drive means can be driven with the stable torque.

  Preferably, the first cloth amount detection means measures the time for which the washing tub rotates by a predetermined angle from the stopped state.

  When the washing tub is stopped, the cloth in the washing tub is biased toward the bottom of the washing tub due to gravity. In this state, since all the gravity of the cloth in the washing tub is applied to the washing tub, the amount of cloth can be accurately detected by measuring the time during which the washing tub rotates by a predetermined angle from the stopped state.

  Preferably, the predetermined angle is 270 degrees or less.

  Preferably, the second cloth amount detecting means obtains the first angular acceleration from the change in angular velocity when the washing tub is rotated with the first torque, and the second cloth amount detecting means rotates the washing tub with the second torque. A second angular acceleration is obtained from the change in angular velocity, and based on the moment of inertia of the washing tub calculated from the first torque, the first angular acceleration, the second torque, and the second angular acceleration, 2 is detected.

  According to this invention, the first angular acceleration is obtained from the change in angular velocity when the washing tub is rotated with the first torque, and the second is obtained from the change in angular velocity when the washing tub is rotated with the second torque. Is obtained, the moment of inertia of the washing tub is calculated from these results, and the amount of cloth is detected. Since the moment of inertia is calculated from the two combinations of torque and angular acceleration, the amount of cloth can be calculated accurately.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol in the figure shows the same or equivalent member, and the overlapping description is not repeated.

  FIG. 1 is a block diagram showing a configuration of a drive control device for a washing machine in the present embodiment. Referring to FIG. 1, drive control apparatus 100 is driven by microcomputer 1 (hereinafter referred to as “microcomputer”) 1, voltage PWM (Pulse Width Modulation) inverter 9 controlled by microcomputer 1, and voltage PWM inverter 9. Motor 10, Hall sensor 11 for detecting a hole provided in the rotating portion of motor 10, current detectors 14 and 15 for measuring the drive current of the motor and inputting the measurement result to microcomputer 1, and angle detector 12 and an angular velocity detector 13.

  The angle detection unit 12 is connected to the hall sensor 11 and detects the rotation angle of the motor 10 based on the output of the hall sensor 11. The output of the angle detector 12 is connected to the microcomputer 1, and the detected rotation angle is output to the microcomputer 1.

  The angular velocity detection unit 13 is connected to the Hall sensor 11 and detects the angular velocity of the motor 10 based on the output from the Hall sensor 11. The output of the angular velocity detector 13 is connected to the microcomputer 1, and the detected angular velocity is output to the microcomputer 1.

  The microcomputer 1 receives motor drive current from the current detectors 14 and 15. The microcomputer 1 outputs three types of voltages Vu *, Vv *, and Vw * to the voltage PWM inverter 9 based on the driving current of the motor 10, the rotation angle of the motor 10, and the angular velocity of the motor 10. The voltage PWM inverter 9 outputs voltages Vu, Vv, Vw for driving the motor 10 to the motor 10 in accordance with the voltages Vu *, Vv *, Vw * input from the microcomputer 1. Control of the motor 10 using the voltage PWM inverter 9 is generally called vector control. Since vector control is a well-known technique, description thereof will not be repeated here. By the vector control, the motor 10 can be driven with a stable torque.

  The microcomputer 1 includes a central processing unit (CPU) 5 for controlling the entire microcomputer 1, a ROM (Read Only Memory) 6 that stores programs and data, and a RAM (Random) that temporarily stores measurement data. Access Memory) 7, a timer 8 for measuring time, a vector control unit 2 for vector control of the motor 10, a first cloth amount detection unit 16 for detecting the amount of cloth in the washing tub, 2 cloth amount detection units 17.

  The vector control unit 2 includes a torque control unit 3 that controls the motor 10 to be driven at a constant torque, and an angular velocity control unit 4 that controls the motor 10 to rotate at a constant angular velocity.

  The CPU 5 executes a program stored in the ROM 6.

  The washing machine of the present embodiment is a drum-type washing and drying machine in which the rotation axis of a cylindrical washing tub is in a horizontal direction with respect to the floor surface. The rotating shaft of the motor 10 is directly or indirectly connected without sliding with the rotating shaft of the washing tub. For this reason, the rotation angle of the washing tub is detected from the rotation angle of the motor 10 detected by the angle detection unit 12.

  The first cloth amount detection unit 16 detects the amount of cloth in the washing tub from the time required for the washing tub to rotate at a predetermined angle by driving the motor 10 with a constant torque.

  The second cloth amount detection unit 17 detects the moment of inertia of the washing tub from a state where the washing tub rotates beyond a predetermined angular velocity, and detects the amount of cloth in the washing tub from the detected moment of inertia.

  The control by the first cloth amount detection unit 16 will be described more specifically. The 1st cloth amount detection part 16 performs the following process.

  (1) From the state where the motor 10 is stopped, a constant torque is applied to the motor 10 to rotate the washing tub. When the motor 10 is stopped, all the cloth in the washing tub is collected at the bottom of the washing tub by gravity.

  (2) The timer 8 measures the time required for the rotation angle of the washing tub from 36 degrees to 216 degrees. This required time is stored in the RAM 7. By this operation, the cloth in the washing tub is lifted up to the upper part of the washing tub. The time until the washing tub rotates 36 degrees from the stopped state is excluded because the static friction until the washing tub starts to move is large.

  (3) The first cloth amount table stored in the ROM 6 is read, the cloth amount corresponding to the required time measured by the timer is extracted, and the extracted cloth amount is set as the first cloth amount.

  The first cloth amount table stored in the ROM 6 applies a constant torque to the motor 10 from the state where the motor 10 is stopped to rotate the washing tub until the rotation angle of the washing tub becomes 36 degrees to 216 degrees. The relationship between the required time and the amount of cloth in the washing tub is stored. The first cloth amount table stored in the ROM 6 is a relationship obtained by measurement through experiments in advance.

  FIG. 2 is a diagram illustrating an example of the cloth amount table. Referring to FIG. 2, when the amount of cloth is equal to or less than a predetermined amount of cloth (here, 4 kg), the relationship between the time required for the rotation angle of the washing tub from 36 degrees to 216 degrees and the amount of cloth is linear. . For this reason, if it is below a predetermined | prescribed cloth amount (here 4 kg), the cloth amount in a washing tub can be detected with high precision from required time. On the other hand, when the amount of cloth is larger than the predetermined amount of cloth (4 kg), the required time and the amount of cloth are not determined linearly. For this reason, the amount of cloth in the washing tub cannot be detected with high accuracy from the required time.

  In addition, the amount of cloth here is the weight in the state which the cloth dried. The predetermined amount of cloth is the amount of cloth when the volume of the cloth in the washing tub occupies half of the volume of the washing tub. When the amount of cloth in the washing tub exceeds a predetermined amount of cloth, the detection accuracy is reduced even when the washing tub is rotated 90 degrees from the state where all of the cloth is collected at the bottom of the washing tub. This is probably because the cloth exists in the lower part and all the cloths are not lifted upward, so that the moment of inertia required for rotation is different from the case of less than half of the volume.

  Here, the time required for the laundry tub to rotate from 36 degrees to 216 degrees (that is, the time required for the laundry tub to rotate 180 degrees) is measured, but the laundry tub is at the first angle (this embodiment). Is equivalent to 36 degrees) and the time required to rotate from the second angle (corresponding to 216 degrees in the present embodiment) may be measured. The first angle may be an angle smaller than the second angle, but is preferably 0 degree (in this embodiment, the rotation start time of the washing tub is 0 degree, but this is not a limitation). The second angle may be an angle of 270 degrees or less, but is preferably 216 degrees. Of course, the combination of the first angle and the second angle is not limited to the present embodiment. For example, the laundry tub needs to rotate from 0 degree (first angle) to 180 degrees (second angle). Even if the time is counted, the time required for the washing tub to rotate from 36 degrees (first angle) to 270 degrees (second angle) may be counted. In the present embodiment, the number of holes detected by the hall sensor 11 is 10. Therefore, the hall sensor 11 can measure the rotation angle of the motor 10 in units of 36 degrees. By increasing the number of holes, the unit of measurement will be different. For example, if there are 360 holes, the rotation angle of the motor 10 can be measured in units of 1 degree. Therefore, the same applies to the number of holes detected instead of the rotation angle. In the present embodiment, the time required from when the first hole is detected until the sixth hole is detected is counted.

  The control by the second cloth amount detection unit 17 will be described more specifically. First, the basic principle of the cloth amount detection by the second cloth amount detection unit 17 will be described.

  The rotational torque torque equation of the washing machine can be assumed as follows.

Tgen-Tfri = J × dω / dt
Where Tgen is the generated torque, J is the moment of inertia of the mechanical system (including the load of the washing tub and the cloth), Tfri is the washing shaft rotational friction torque, and dω / dt is the differential (angular acceleration) of the angular velocity ω.

  The torque control unit 3 of the vector control unit 2 calculates the torque contribution current component Iq based on the input values from the current detection units 14 and 15 and the angle detection unit 12. The torque control unit 3 can keep the generated torque Tgen constant according to the following equation by controlling the torque contributing current component Iq to be constant.

_Tgen = pole × φ _fa × Iq
Here, pole is the number of rotor poles of the motor, and φ _fa is the maximum number of three-phase winding flux linkage.

  When the generated torque during acceleration is controlled to Tgen (+) and the braking torque during deceleration is controlled to Tgen (−), and the measured angular accelerations are dω (+) / dt and dω (−) / dt, the following is performed. Become.

Tgen (+) − Tfri = J × dω (+) / dt
Tgen (−) − Tfri = J × dω (−) / dt
If the friction torque Tfri during acceleration / deceleration hardly changes, the inertia moment J is calculated by the following equation (1).

J = (Tgen (+) − Tgen (−)) / (dω (+) / dt−dω (−) / dt) (1)
As a result, an accurate moment of inertia can be calculated without being affected by variations in the friction torque Tfri due to temperature.

  Next, the control by the second cloth amount detection unit 17 will be described with a specific example. First, acceleration is performed with a predetermined torque. The actual angular velocity when it is detected that a predetermined angular velocity (10 rad / sec) has been exceeded is stored in the RAM 7 (assuming it is 11 rad / sec), and the timer 8 of the microcomputer 1 is started at the same time. . Then, the actual angular velocity at the time when it is detected that the angular velocity exceeds 18 rad / sec is also stored in the RAM 7 (assuming 18.5 rad / sec), and the acceleration time is determined from the elapsed time of the timer 8 at that time. Can be calculated. If the elapsed time is 2 seconds, the angular acceleration can be calculated by the following formula.

dω (+) / dt = (18.5-11.0) /2=3.75
Similarly, at the time of deceleration, the actual angular velocity at the time when it is detected that the angular velocity has dropped below 18 rad / sec is stored in the RAM 7 (assuming 17.5 rad / sec) and at the same time the timer 8 of the microcomputer 1 is reset. Start. Then, the actual angular velocity at the time of detecting that the angular velocity has dropped below 10 rad / sec is also stored in the RAM 7 (assumed to be 8.5 rad / sec), and decelerated from the elapsed time of the timer 8 at that time. The angular acceleration at the time can be calculated. If the elapsed time is 3 seconds, the angular acceleration can be calculated by the following formula.

dω (−) / dt = (8.5-17.5) /3=−3.00
The moment of inertia J is calculated by substituting the above result into equation (1). If this case is applied, it will be as follows.

J = (3-(− 1.5)) / (3.75− (3.00)) = 0.667
The second cloth amount detection unit 17 reads the second cloth amount table stored in the ROM 6, extracts the cloth amount corresponding to the obtained moment of inertia J, and sets the extracted cloth amount as the second cloth amount. . The second cloth amount table stored in the ROM 6 defines the relationship between the moment of inertia of the washing tub and the amount of cloth in the washing tub. The second cloth amount table stored in the ROM 6 stores a relationship obtained by measurement in advance through experiments. FIG. 3 is a diagram illustrating an example of a second cloth amount table showing the relationship between the moment of inertia and the cloth amount.

  FIG. 4 is a flowchart showing the flow of the cloth amount detection process executed by the washing machine in the present embodiment. In the following description, the operation of detecting the first cloth amount by the first cloth amount detector 16 is referred to as first cloth amount detection. The operation of detecting the second cloth amount by the second cloth amount detector 17 is referred to as second cloth amount detection. Referring to FIG. 4, in step S <b> 1, the first cloth amount detection is performed after detecting that the motor 10 is stopped and the washing tub is not moving. While the motor is stopped, all the cloth in the washing tub accumulates at the bottom of the tub by gravity. Here, the motor 10 is rotated by applying a constant torque using the torque control unit 3, the required time from the rotation angle of the washing tub of 36 degrees to 216 degrees is measured by the timer 8, and this required time is stored in the RAM 7. To do.

  In step S <b> 2, the first cloth amount is determined based on the relationship between the first cloth amount table prepared in the ROM 6 and the required time stored in the RAM 7. The first cloth amount is temporarily stored in the RAM 7.

  In step S3, the number of rotations of the motor 10 is increased, and the cloth is attached to the washing tub. If there is uneven distribution of the cloth that is stuck, increasing the number of rotations will cause abnormal vibration. For this reason, in step S4, in order to detect uneven distribution of the cloth in the washing tub, a change in the angular velocity of the washing tub is detected. In step S3, a predetermined torque is applied to accelerate the washing tub, and a change in angular velocity that is predicted to rotate stably with the torque is detected. This angular velocity is determined by the moment of inertia of the washing tub and the torque generated by the motor 10.

  In step S5, the presence or absence of uneven distribution is detected from the fluctuation range of the angular velocity detected in step S4. Since the size of the uneven distribution depends on the amount of cloth in the washing tub, a threshold table defining the relationship between the amount of cloth in the washing tub and the fluctuation range of the angular velocity for detecting the uneven distribution is stored in the ROM 6 in advance. deep. The first cloth amount detected by the first cloth amount detector 16 is used as the cloth amount in the washing tub. Therefore, in step S4, the detected angular velocity is compared with the threshold value defined in the threshold value table corresponding to the first cloth amount, and the presence or absence of uneven distribution is detected. If the variation in angular velocity is greater than the threshold value, it is determined that there is uneven distribution, and the process proceeds to step S5A. In step S5A, the angular velocity of the motor 10 is decreased and the process returns to step S3. This is to prevent abnormal vibration by repeatedly detecting the uneven distribution of the cloth from the cloth attaching operation.

  In step S5, when the fluctuation of the angular velocity is equal to or less than the threshold value, it is determined that there is no uneven distribution, and the process proceeds to step S6.

  In step S6, it is determined whether or not the second cloth amount detection is performed. As described with reference to FIG. 2, the first cloth amount detected by the first cloth amount detector 16 has low detection accuracy when the cloth amount in the washing tub exceeds a predetermined cloth amount (4 kg in this case). . For this reason, when the first cloth amount is larger than the predetermined cloth amount, the process proceeds to step S7 in order to obtain an accurate cloth amount by the second cloth amount detection. When the first cloth amount is equal to or less than the predetermined cloth amount, the process proceeds to step S10. When proceeding to step S10, steps S7 to S9 are not executed. That is, the second cloth amount detection is not performed.

  In step S10, the first cloth amount detected in step S2 is determined as the cloth amount in the washing tub, and the cloth amount detection ends. In this case, the time required for the cloth amount detection is the time when the uneven distribution detection is executed once in the shortest time. This is because the first cloth amount detection is completed while the laundry tub is accelerated by applying a predetermined torque in order to detect the uneven distribution.

  In step S7, second cloth amount detection is performed. In the second cloth amount detection, the motor 10 is controlled so as to apply a constant acceleration torque (first torque) to the washing tub, and the first angular acceleration of the motor 10 is obtained. Next, the motor 10 is controlled so as to apply a constant braking torque (second torque) to the washing tub, and a second angular acceleration of the motor 10 is obtained. The inertia moment J of the washing tub is obtained by substituting the first and second torques and the first and second angular accelerations into the above-described equation (1).

  In step S8, the second cloth amount is detected by extracting the second cloth amount from the second cloth amount table stored in the ROM 6 from the obtained value of the moment of inertia J.

  In step S9, the second cloth amount detected by the second cloth amount detector 17 is set as the cloth amount in the washing tub, and the cloth amount detection is ended. Thereafter, the subsequent operation of the washing machine is performed using the determined amount of cloth. For example, in the washing machine according to the present embodiment, the dehydrating operation is performed by starting acceleration from the speed immediately after the detection of the cloth amount before dehydration is completed. This dehydrating operation is controlled based on the first cloth amount detected by the first cloth amount detector 16 or the second cloth amount detected by the second cloth amount detector 17.

  FIG. 5 is a diagram showing temporal changes in the angular velocity of the washing tub when the cloth amount detection process shown in FIG. 4 is executed. Referring to FIG. 5, the solid line shows the relationship between the angular velocity of the washing tub and time when the amount of cloth in the washing tub is equal to or less than the predetermined amount of cloth. The dotted line indicates the relationship between the angular velocity of the washing tub and time when the amount of cloth in the washing tub exceeds a predetermined amount of cloth.

  When the amount of cloth in the washing tub indicated by the solid line in the drawing is smaller than the predetermined amount of cloth, the washing tub is rotationally controlled in the order of first cloth amount detection and uneven distribution detection. At this time, since the second cloth amount detection is not performed, the time required for performing the second cloth amount detection is shortened. The first cloth amount detection is performed at a stage before the uneven distribution detection is performed, that is, at a stage before the laundry tub is stopped and before reaching a predetermined angular acceleration. For this reason, since the first cloth amount detection is performed at the preparation stage for detecting the uneven distribution, when the uneven distribution detection is performed, it is not necessary to have a special time for performing the first cloth amount detection. In addition, when uneven distribution detection is not performed, the first cloth amount detection is performed at the stage of accelerating the rotation of the washing tub in order to perform a process executed after the cloth amount is detected, for example, a dehydration process. Since the amount detection is executed, no special time is required for the first cloth amount detection.

  When the amount of cloth in the washing tub indicated by the dotted line in the drawing is larger than the predetermined amount of cloth, the rotation of the washing tub is controlled in the order of first cloth amount detection, uneven distribution detection, and second cloth amount detection. At this time, the first cloth amount detection is performed at a stage before uneven distribution detection is performed, that is, at a stage before reaching a predetermined angular acceleration from a state where the washing tub is stopped. For this reason, since the first cloth amount detection is performed at the preparation stage for detecting the uneven distribution, when the uneven distribution detection is performed, it is not necessary to have a special time for performing the first cloth amount detection. Further, when the second cloth amount detection is performed, the washing tub needs to be rotated at a predetermined angular velocity. However, since the second cloth amount detection is performed after the uneven distribution detection, the second detection is performed. However, the period for rotating the washing tub to a predetermined angular velocity can be omitted. When the uneven detection is omitted, since the second detection is performed after the first detection, the first detection can be performed while the washing tub is rotated to a predetermined angular velocity to perform the second detection. As a result, no special time is required to perform the first detection.

  In the figure, the time required for the first detection and the time required for uneven distribution detection are the same for the case where the amount of cloth in the washing tub is less than the predetermined amount and for the case where the amount is uneven. Each time will be different. The time required for the first cloth amount detection and the uneven distribution detection requires a longer time as the cloth amount increases.

  The time required for the first cloth amount detection and uneven distribution detection varies depending on the cloth amount in the washing tub to be used.

  In the washing machine according to the present embodiment, the uneven distribution detection is performed after the first cloth amount detection, but the uneven distribution detection is not necessarily performed.

  As described above, in the washing machine according to the present embodiment, the first cloth amount detection unit 16 has a precision equal to or less than the predetermined cloth amount and can be detected by the second cloth amount detection unit 17. Before it becomes, the first cloth amount is detected. For this reason, when the amount of cloth in the washing tub is equal to or less than the predetermined amount of cloth, it is not necessary to detect the amount of cloth by the second cloth amount detection unit 17, and therefore the time for detecting the amount of cloth can be shortened. it can.

  In addition, since the first cloth amount detection unit 16 detects the first cloth amount before detection by the uneven distribution detecting means and before the washing tub reaches a predetermined angular velocity, the first cloth amount is detected. It is not necessary to provide a special time for the detection unit 16 to detect the cloth amount.

  Moreover, since the vector control part 2 is controlled so that the angular velocity of a washing tub falls below a predetermined angular velocity when uneven distribution is detected by the uneven distribution detection, by reducing the centrifugal force applied to the cloth in the washing tub The state where the cloth is unevenly distributed can be eliminated.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a block diagram which shows the structure of the drive control apparatus of the washing machine in this Embodiment. It is a figure which shows an example of the cloth amount table. It is a figure which shows an example of the 2nd cloth amount table which shows the relationship between an inertia moment and the cloth amount. It is a flowchart which shows the flow of the cloth amount detection process performed with the washing machine in this Embodiment. It is a figure which shows the time change of the angular velocity of a washing tub when the cloth amount detection process is performed.

Explanation of symbols

  1 microcomputer, 2 vector control unit, 3 torque control unit, 4 angular velocity control unit, 5 CPU, 6 ROM, 7 RAM, 8 timer, 9 voltage PWM inverter, 10 motor, 11 hall sensor, 12 angle detection unit, 13 angular velocity detection Part, 14, 15 Current detection part, 16 1st cloth amount detection part, 17 2nd cloth amount detection part, 100 Drive control apparatus.

Claims (8)

Driving means for rotating the washing tub;
Drive control means for controlling the drive means;
Angle detection means for detecting the rotation angle of the washing tub;
Angular velocity detection means for detecting the angular velocity of the washing tub;
Storage means for storing the relationship between the time required to rotate the laundry tub by a predetermined angle by changing the angular velocity of the laundry tub and the amount of cloth;
By changing the angular velocity of the washing tub and measuring the time for which the washing tub rotates by the predetermined angle, the inside of the washing tub is based on the relationship between the time measured, the stored time, and the amount of cloth. First cloth amount detecting means for detecting the first cloth amount;
A second cloth amount detection for detecting a moment of inertia of the washing tub from a state where the washing tub has rotated beyond a predetermined angular velocity and detecting a second amount of cloth in the washing tub from the detected moment of inertia. Means and
The first cloth amount detection means has an accuracy below a predetermined cloth amount, and the first cloth amount before the washing tub can be detected by the second cloth amount detection means. Detecting a washing machine.   Based on the first cloth amount without activating the second cloth amount detection means when the first cloth amount detected by the first cloth amount detection means is equal to or less than the predetermined cloth amount. The washing machine according to claim 1, further comprising control means for controlling the drive means.   The control means activates the second cloth amount detecting means when the first cloth amount detected by the first cloth amount detecting means exceeds the predetermined cloth amount, and the second cloth amount is activated. The washing machine according to claim 2, wherein the driving unit is controlled based on the second cloth amount detected by the detecting unit.   2. The washing machine according to claim 1, wherein the rotation axis of the washing tub is substantially horizontal with respect to a floor surface or is inclined such that an opening of the washing tub faces upward.   The washing machine according to claim 1, wherein the drive control means drives the drive means using vector control.   2. The washing machine according to claim 1, wherein the first cloth amount detection unit measures a time during which the washing tub rotates by the predetermined angle from a stopped state.   The washing machine according to claim 1, wherein the predetermined angle is 270 degrees or less. The second cloth amount detecting means obtains a first angular acceleration from a change in angular velocity when the washing tub is rotated with a first torque, and when the washing tub is rotated with a second torque. Find the second angular acceleration from the change in angular velocity,
The second cloth amount is detected based on the moment of inertia of the washing tub calculated from the first torque, the first angular acceleration, the second torque, and the second angular acceleration. The washing machine according to claim 1.

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