JP7426197B2 - washing machine - Google Patents

Description

This relates to a washing machine that calculates the weight of laundry.

Techniques for determining the weight of laundry inside a washing machine are known. If you know the weight of the laundry, you can change the washing time, amount of water, etc. accordingly. For example, Patent Document 1 describes detecting the weight of laundry based on the rise time and fall time of the rotational speed of a motor.

Japanese Patent Application Publication No. 2002-126390

The inventors of the present application have noticed that prior art washing machines have reduced accuracy in weight detection, especially when there is an imbalance in the laundry.

According to an embodiment, a drum for storing laundry, a motor for rotating the drum, a controller for controlling rotation of the motor, a detector for detecting a rotational speed of the drum, and first and second acceleration sections. The washing machine includes a processing unit that calculates the weight of the laundry based on the rotational speed in the washing machine, and the controller is configured such that the absolute value of the rotational speed at the starting point of the first and second acceleration sections is the same. , a washing machine is provided in which the rotation of the motor is controlled so that the rotation of the motor is reversed in sign.

According to an embodiment, a drum for storing laundry, a motor for rotating the drum, a controller for controlling rotation of the motor, a detector for detecting a rotational speed of the drum, and first and second acceleration sections. The washing machine includes a processing unit that calculates the weight of the laundry based on the rotational speed in the washing machine, the controller comprising a processing unit that calculates the weight of the laundry based on the rotational speed at a first constant speed in which the rotational speed is constant before the first and second acceleration sections. A washing machine is provided in which the rotation of the motor is controlled to provide a high speed section and a second constant speed section.

The weight of the laundry inside the washing machine can be determined with better accuracy.

FIG. 1 is a diagram showing the structure of a washing machine according to an embodiment. It is a figure which shows the profile of the intermittent drive of a motor for determining the weight of laundry. It is a figure which shows the profile of the intermittent drive of a motor for determining the weight of laundry. It is a figure showing the eccentric position resulting from deviation in the drum of laundry.

In the following description and drawings, corresponding parts are designated with the same reference numerals. The dimensions of elements in the drawings are not necessarily drawn to scale.

Hardware FIG. 1 is a diagram illustrating the structure of a washing machine 100 according to an embodiment. The washing machine 100 includes a drum 110 that stores laundry, a motor 120 that rotates the drum 110, a controller 130 that controls the rotation of the motor 120, a detector 140 that detects the rotational speed of the drum 110, and a processing section 150. . In some embodiments, detector 140 detects the rotation angle of drum 110 in addition to the rotation speed of drum 110. The processing unit 150 calculates the weight of the laundry based on the rotational speed in the first and second acceleration sections, which will be described later.

In various embodiments, the rotational speed of drum 110 is utilized. Detector 140 is a position sensor that directly detects the rotational speed of drum 110, but is not limited thereto, and may be any suitable sensor.

Processing unit 150 typically includes a processor 152 and memory 154. The processor 152 executes a computer program that controls the rotation of the drum 110 and the motor 120 and calculates the weight of the laundry. Memory 154 typically stores such computer programs and associated data. Processor 152 outputs a signal to control the rotation of motor 120 to controller 130. Controller 130 drives motor 120 based on control signals from processor 152. Although the controller 130 and the processing unit 150 are shown as separate functional blocks in FIG. 1, they may be realized as a single functional block.

Intermittent Drive FIG. 2 is a diagram illustrating a profile 200 of intermittent drive of the motor 120 for determining the weight of laundry. The horizontal axis in FIG. 2 represents time, and the vertical axis represents the rotational speed of drum 110. The profile 200 includes a first constant speed section 211, a first acceleration section 212, a stop section 215, a second constant speed section 221, and a second acceleration section 222. The sign of the rotation speed represents the direction of rotation of the drum 110. Therefore, here, the drum 110 rotates in a certain direction from time 0 to the stop section 215, and thereafter rotates in the opposite direction.

In some embodiments, the controller 130 controls the rotation of the motor 120 such that the absolute values of the rotational speeds of the drum 110 at the starting points of the first acceleration section 212 and the second acceleration section 222 are the same and have opposite signs. .

Continuous Drive FIG. 3 is a diagram illustrating a profile 300 of continuous drive of motor 120 for determining the weight of laundry. The horizontal axis in FIG. 3 represents time, and the vertical axis represents the rotation speed of drum 110. The profile 300 includes a first constant speed section 311, a first acceleration section 312, a second constant speed section 321, and a second acceleration section 322. Profile 300 differs from profile 200 in that there is no stop section.

In some embodiments, a constant speed section, an acceleration section, and a deceleration section may be provided before the first constant speed section 311. Thereby, the position of the laundry within the drum 110 can be fixed in advance.

In one embodiment, the controller 130 may provide a first constant speed section 311 and a second constant speed section 321 in which the rotational speed of the drum 110 is constant before the first acceleration section 312 and the second acceleration section 322, respectively. Controls the rotation of the motor 120.

FIG. 4 is a diagram illustrating eccentric positions caused by unevenness of laundry within the drum 110. The drum 110 rotates around a rotating shaft 410. The laundry 420 in the drum 110 may be unevenly distributed as shown in FIG. 4 . At this time, the center of gravity 430 of the drum 110 also shifts from the rotation axis 410 due to the bias of the laundry 420. If a reference line 440 is a line where a vertical plane that passes through the rotating shaft 410 intersects with the opening of the drum 110, then the angle of the center of gravity 430 measured from the reference line 440 is the eccentricity caused by the misalignment of the laundry inside the drum 110. Let the position be 450. Eccentric position 450 can range from 0 degrees to 360 degrees. In this disclosure, the position of drum 110 is represented by eccentric position 450, which is also referred to as phase.

Starting Points of the First and Second Acceleration Sections In embodiments using profile 200 (intermittent drive) or profile 300 (continuous drive), the starting points of the first and second acceleration sections are within the drum 110 of the laundry 420. The eccentric position 450 caused by the deviation in corresponds to two points shifted by 180 degrees. In an embodiment using profile 300 (continuous drive), as shown in FIG. 450 is 90 degrees. Therefore, the starting points of the first acceleration section 312 and the second acceleration section 322 correspond to two points where the eccentric position 450 due to the deviation of the laundry 420 within the drum 110 is shifted by 180 degrees. In other embodiments using the profile 200 (intermittent drive), the starting points of the first acceleration section 212 and the second acceleration section 222 are such that the eccentric position 450 due to the deviation of the laundry 420 within the drum 110 is 180 degrees. Corresponds to the two shifted points.

In embodiments using profile 200 (intermittent drive) or profile 300 (continuous drive), the drum 110 rotates n (n: natural number) during the first acceleration section and the second acceleration section. For example, in some embodiments, the drum 110 makes one revolution during the first acceleration section 312 and the second acceleration section 322. Without being limited to this, if the number of rotations of the drum 110 in the first acceleration section 312 and the second acceleration section 322 are the same, the drum 110 can rotate by any number of rotations n (n: natural number) other than one rotation. You may. Here, the "number of rotations" of the drum refers to the number of times the drum rotates. For example, the drum 110 may rotate twice in the first acceleration section 312 and the second acceleration section 322.

Weight Detection In embodiments using profile 200 (intermittent drive) or profile 300 (continuous drive), the processing unit 150 determines the weight based on the weight detected in the first and second acceleration sections. If the torque of the motor 120 is constant, the acceleration in the first and second acceleration sections depends on the weight of the laundry 420. For example, if the weight of the laundry 420 is heavy, the increase in rotational speed will be small even if it is accelerated in the acceleration section, but if the weight of the laundry 420 is light, the increase in the rotational speed will be large if it is accelerated in the acceleration section. Therefore, the processing unit 150 can determine the weight of the laundry 420 from the increases in the two rotational speeds obtained in the first and second acceleration sections.

In embodiments using profile 200 and profile 300, the angle between the rotation axis of drum 110 of washing machine 100 of the present disclosure and the horizontal direction is 0 degrees to 45 degrees. Within this range, the weight of the laundry 420 can be more effectively determined from the two weight values based on the accelerations in the first acceleration section and the second acceleration section. Washing machines in this range include what is generally called a drum type washing machine. In a drum-type washing machine, the rotation axis of the drum 110 is relatively close to the horizontal direction. Therefore, due to the influence of gravity, the rotational speed tends to decrease when the eccentric position 450 moves upward, and the rotational speed tends to increase when the eccentric position 450 moves downward. Even if such rotational speed fluctuations occur, the true weight of the laundry 420 can be determined based on the two weight values of the laundry 420 obtained separately in the first acceleration period and the second acceleration period, as described below. It is possible to obtain a value closer to the weight of .

Considering the example of FIG. 3, the starting points of the first acceleration section 312 and the second acceleration section 322 correspond to two points where the eccentric position 450 caused by the deviation of the laundry 420 in the drum 110 is shifted by 180 degrees. Therefore, there is an effect that errors when detecting the weight of the laundry 420 can be reduced. This effect can also be obtained in the example of FIG. More preferably, the weight of the laundry 420 is determined by averaging the two weights detected in the first and second acceleration sections. This further reduces errors when detecting the weight of laundry 420.

By continuously operating the profile 300, weight detection can be performed twice while maintaining the placement of the laundry 420 within the drum 110, that is, while maintaining the eccentric position and amount of imbalance. Here, the unbalance amount is a parameter determined by the weight of the laundry 420 that corresponds to the imbalance in the drum 110 and the distance of the laundry 420 from the rotating shaft 410. The larger the value, the larger the amount of unbalance. When the rotation direction changes as shown in the profile 200, a section where the motor 120 stops occurs, and in this section, the centrifugal force is lost and the laundry 420 stuck to the side of the drum 110 falls vertically downward. Therefore, the arrangement of the laundry 420 may change. At this time, the eccentric position and the amount of imbalance will change. Even if the eccentric position can be corrected by monitoring the phase of the rotational speed, etc., the amount of unbalance cannot be corrected completely, so the profile 200 has larger variations than the profile 300. For this reason, profile 300 is preferable to profile 200.

In embodiments using the profile 300, the first acceleration period 312 and the second acceleration period 322 are performed during continuous operation of the drum, and the rotational speed of the drum is 30 revolutions between the first acceleration period 312 and the second acceleration period 322. /min or more. This may reduce the movement of the laundry 420 within the drum 110 between the first acceleration section 312 and the second acceleration section 322. As a result, errors in detecting the weight of laundry 420 can be reduced.

Start point phase detection (rotation angle)
As described above, the starting points of the first acceleration section (for example, 312) and the second acceleration section (for example, 322) are two points where the eccentric position 450 due to the deviation of the laundry 420 within the drum 110 is shifted by 180 degrees. handle. Therefore, it is necessary to detect that the phase of the eccentric position 450 is shifted by 180 degrees at the starting points of the first acceleration section and the second acceleration section.

In one embodiment, the processing unit 150 determines two points whose phases are shifted by 180 degrees in this way based on the rotation angle of the drum 110. The rotation angle of drum 110 may be detected by detector 140. More specifically, the difference between the rotation angles of two points whose phases are 180 degrees apart corresponds to (n+0.5) rotations (n: natural number). To detect the phase of the starting point based on the rotation angle, it is sufficient to memorize the angle of the starting point of the first acceleration section and start the second acceleration section at the timing when the rotation angle is deviated by 180 degrees from the memorized angle. . Phase detection of the starting point based on the rotation angle provides higher accuracy of phase detection in embodiments using profile 300 (continuous drive).

Phase detection of starting point (rotation speed, current, voltage)
In an embodiment, the processing unit 150 determines the two points having a phase difference of 180 degrees based on at least one of the rotational speed of the drum 110, the current flowing through the motor 120, and the voltage applied to the motor 120. demand. More specifically, at two points where the phases are shifted by 180 degrees, the difference in phase of one of the rotational speed of the drum 110, the current flowing to the motor 120, and the voltage applied to the motor 120 is 180 degrees.

Due to the influence of the eccentric position 450 caused by the unevenness of the laundry 420 within the drum 110, the rotational speed of the drum fluctuates even in a constant speed section. When this variation in rotational speed is plotted on the time axis, it becomes sinusoidal. There is a correlation between the phase of this waveform and the eccentric position 450. Therefore, the eccentric position 450 can be determined from the phase of the sinusoidal waveform representing the variation in rotational speed. As the deviation of the laundry 420 within the drum 110 becomes smaller, the amplitude of the waveform becomes smaller, making it difficult to detect the phase. However, if the bias is small, the effect on weight detection is small in the first place, so even if the phase cannot be detected, there is almost no effect on the difference (that is, dispersion) in weight detected in the two acceleration sections. In any case, by detecting the phase of the rotational speed fluctuation waveform, the second acceleration section can be started at a timing shifted by 180 degrees from the starting point of the first acceleration section.

In the same way that the rotational speed of the drum described above fluctuates, the current flowing through the motor 120 and the voltage applied to the motor 120 also fluctuate in the constant speed section. Therefore, the phase of the starting point can be similarly detected using either the current flowing through the motor 120 or the voltage applied to the motor 120. The current flowing through the motor 120 and the voltage applied to the motor 120 can be detected by the controller 130, for example.

As described above, the weight of the laundry 420 can be determined based on the acceleration in the first acceleration period and the second acceleration period. In the embodiment using profile 200 (intermittent drive) and profile 300 (continuous drive), the rotational speed of the drum 110 at the end of the first acceleration section and the second acceleration section is 300 revolutions per minute due to the load on the motor 120, etc. Preferably, it is less than 1 minute. Within this range, the weight of the laundry 420 can be determined more effectively based on the acceleration in the first acceleration section and the second acceleration section.

Each of the various functions in this disclosure may be implemented with a single element or with multiple elements. Conversely, multiple functions may be realized by a single element. Each function may be realized by hardware, software, or a combination of hardware and software. The flow diagrams in this disclosure include multiple blocks. Processing of these blocks may be done serially or in parallel. Further, the order of some blocks may be changed.

The main body of the apparatus and method in the present disclosure includes a computer. When this computer executes the program, the main functions of the apparatus and method of the present disclosure are realized. A computer includes, as its main hardware configuration, a processor that operates according to a program. The type of processor does not matter as long as it can implement a function by executing a program. A processor is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or a large scale integration (LSI). A plurality of electronic circuits may be integrated on one chip or may be provided on a plurality of chips. A plurality of chips may be integrated into one device, or may be provided in a plurality of devices.

What has been described above includes various examples of the invention. For the purpose of describing the invention, it is of course not possible to describe every possible combination of elements and steps, but those skilled in the art will recognize that many further combinations and permutations of the invention are possible. right. Accordingly, the invention is intended to cover all such modifications, changes, and modifications as come within the spirit and scope of the claims.

100 washing machine 110 drum 120 motor 130 controller 140 detector 150 processing unit 152 processor 154 memory

Claims (8)

drum for storing laundry,
a motor that rotates the drum;
a controller that controls rotation of the motor;
a detector for detecting the rotational speed of the drum; and
A drum -type washing machine comprising a processing section that detects the weight of the laundry,
The controller is
a first constant speed section in which the rotational speed is constant while the drum is rotating in one direction; and a first acceleration section in which the rotational speed is accelerated continuously from the first constant speed section; After the first acceleration section, a second constant speed section in which the rotational speed is constant and a second acceleration section in which the rotational speed is accelerated in succession to the second constant speed section are provided, and the first controlling the rotation of the motor so that the start point of the acceleration section and the start point of the second acceleration section correspond to two points at which the rotation angle of the drum is shifted by 180 degrees;
The processing unit includes:
While the motor is outputting a constant torque, a first weight value of the laundry is determined based on the rotational speed in the first acceleration section, and a first weight value of the laundry is determined based on the rotational speed in the second acceleration section. configured to detect the weight of the laundry by determining a second weight value of the item and averaging the first weight value and the second weight value,
Before the first constant speed section, a preliminary constant speed section in which the rotational speed is constant, a preliminary acceleration section in which the rotational speed is accelerated following the constant speed section, and a preliminary acceleration section in which the rotational speed is accelerated in the acceleration section. A washing machine that is provided with a deceleration section that continuously decelerates the rotation speed to the above rotation speed . The washing machine according to claim 1, wherein the difference between the rotation angles at the two points corresponds to (n+0.5) rotations (n: natural number). The washing machine according to claim 1, wherein the two points are determined based on at least one of the rotational speed, the current flowing through the motor, and the voltage applied to the motor. The washing machine according to claim 3, wherein a difference in phase of one of the rotational speed, the current flowing to the motor, and the voltage applied to the motor at the two points is 180 degrees. The first and second acceleration sections are performed during continuous operation of the drum,
The washing machine according to claim 1, wherein the rotational speed is maintained at 30 revolutions/minute or more between the first and second acceleration sections. The washing machine according to claim 1, wherein the rotational speed at the end points of the first and second acceleration sections is 300 revolutions/minute or less. The washing machine according to claim 1, wherein the angle between the rotating shaft of the drum and the horizontal direction is 0 degrees to 45 degrees. The washing machine according to claim 1, wherein the drum rotates n times (n: natural number) in the first and second acceleration sections.

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