JP2011160845A - Washing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a washing machine capable of taking torsional vibrations into consideration and reducing force and noise transmitted to a floor by vibrations by solving such the problem that there is the case that a rotation angle by the torsional vibration is different even when a vibration amplitude is equal and the force and noise transmitted to a floor surface increase as the rotation angle is larger, while conventionally the increase of the vibrations is prevented by measuring the vibration amplitude and stopping or decelerating the rotation of a drum when the vibration amplitude is larger than a preset threshold. <P>SOLUTION: The washing machine includes a rotation angle detector for measuring the torsional vibration of an outer tub, and the rotation of the drum is stopped or decelerated when the output is larger than a preset value. The vibration amplitude and the rotation angle when the vibration amplitude takes the maximum value by one rotation of the drum are measured. Since the vibration amplitude and rotation angle are different depending on unbalance position and amount, they can be estimated respectively by obtaining the relationship between them beforehand. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a washing machine having a configuration in which an outer tub containing a drum and a casing are supported by a vibration isolator.

  For example, in a conventional drum-type washing machine, a drum for storing laundry is generally connected to an outer tub for storing water via a shaft. Further, the drum is rotated by a motor via a shaft. The outer tub is supported on the casing by a vibration isolator so that vibrations generated in the washing, dehydrating and drying processes are not transmitted to the casing.

  In order to perform low-vibration, low-noise dehydration operation in a drum-type washing machine, the laundry is evenly stuck to the inner wall of the drum, and the rotation speed of the drum is reduced with less laundry unbalance. The problem is whether to dehydrate. Until now, the output of the vibration detection device installed in the outer tub or housing detects the size of the imbalance and increases the rotation speed to perform dehydration or decreases the rotation speed of the drum to make the laundry even. A method for determining whether to start over from the pasting process has been proposed. However, the vibration modes that appear prominently depend on the position of occurrence of unbalance, and it is difficult to grasp the vibration of the outer tub with one sensor.

  In view of this, a method has been proposed in which the front and rear positions of unbalance are determined, and a threshold value for changing the rotational speed according to the result is changed. For example, the vibration detection means that can detect vibrations in multiple directions of two or more axes identifies the unbalance position in the front-rear direction of the laundry from the phase difference of each vibration component, and shifts to high-speed dehydration according to the unbalance position There has been proposed a method for individually setting the threshold value of the determination means (Patent Document 1).

JP 2006-311885 A

  With the configuration of Patent Document 1, it is possible to grasp the position of the unbalance in the front-rear direction, but it is difficult to grasp the rotation angle of the outer tub by torsional vibration. Even if the vibration amplitude is the same, the greater the rotation angle, the greater the force and noise transmitted to the floor. Therefore, it is important to detect the rotation angle as well as the unbalanced front and rear positions.

  Therefore, an object of the present invention is to provide a washing machine that can reduce the force and noise transmitted to the floor by vibration in consideration of the torsional vibration.

In a washing machine provided with a drum for storing laundry, an outer tub containing the drum, a drive mechanism for rotationally driving the drum, and a control device for controlling the drive mechanism,
There is a rotation angle detection device that measures the magnitude of torsional vibration around at least one of the vertical axis and the axis perpendicular to the rotation axis of the drum, and the rotation of the drum is controlled based on the output of the rotation angle detection device. It is characterized by controlling.

  When the position and amount of unbalance are detected based on the outputs of the vibration detection device and the rotation angle detection device, and are determined to be larger than a threshold value set in advance according to the unbalance position and the drum rotation speed. In this case, the rotation of the drum is stopped, or the dehydration operation with low vibration is performed by decelerating and restarting.

  According to the present invention, since the rotation of the drum is controlled based on the output of the rotation angle detection device, when the rotation angle is large, the rotation of the drum can be stopped, or the dehydration activation can be performed by restarting the operation after decelerating. A low-vibration drum-type washing machine can be obtained.

  In addition, according to the present invention, it is possible to specify the state of the bias of the laundry so that the vibration becomes large from the displacement and the rotation angle of the outer tub, and perform highly accurate imbalance determination, and according to the result By appropriately controlling the drum rotation speed, a dehydration operation with small vibration can be performed.

It is an external view which shows the drum type washing machine of this invention. It is a perspective view which cut | disconnects a part of housing | casing of the drum type washing machine of this invention, and shows an internal structure. It is a right view for showing the internal structure of the drum type washing machine of the present invention. It is a block diagram which shows the control system of the drum type washing machine of this invention. It is a figure which shows the vibration amplitude and rotation angle in case an unbalance exists ahead. It is a figure which shows a vibration amplitude and rotation angle in case an imbalance exists back. It is a figure which shows the relationship between a vibration amplitude and a rotation angle. It is a flowchart which shows control of the low speed area | region in the spin-drying | dehydration process of this invention. It is a flowchart which shows control of the high-speed area | region in the spin-drying | dehydration process of this invention. It is a schematic diagram which shows the vibration of an outer tank, and a vibration detection direction.

(First embodiment)
Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is an external view of a drum-type washing machine according to an embodiment of the present invention. FIG. 2 is a perspective view in which a part of the housing is cut to show the internal structure, and FIG. 3 is a right side view of the internal structure.

  A casing 1 constituting the outer shell is mounted on a base 1h, and left and right side plates 1a and 1b (not shown), a front cover 1c, a back cover 1d (not shown), an upper cover 1e, and a lower front face. It is comprised by the cover 1f. The left and right side plates 1a and 1b are connected by a U-shaped upper reinforcing material (not shown), a front reinforcing material (not shown), and a rear reinforcing material (not shown), and include a base 1h. A box-shaped housing 1 is formed and has sufficient strength as a housing.

  The door 2 is for closing a loading slot for putting in and out the laundry provided in the approximate center of the front cover 1c, and is supported by a hinge provided in the front reinforcing member so as to be opened and closed. When the door release button 2a is pressed, the lock mechanism (not shown) is released and the door is opened, and when the door is pressed against the front cover 1c, the door is locked and closed. The front reinforcing member has a circular opening for taking in and out the laundry concentrically with the opening of the outer tub described later.

  The operation / display panel 3 provided in the upper center of the housing 1 includes a power switch 4, an operation switch 5, and a display 6. The operation / display panel 3 is electrically connected to a control device 7 provided at the bottom of the housing 1.

  The drum 8 shown in FIG. 2 is rotatably supported, has an outer peripheral wall and a bottom wall with a large number of through holes for water flow and ventilation, and an opening 8a for taking in and out laundry on the front end face. Is provided. A fluid balancer integrated with the drum 8 is provided outside the opening 8a. A plurality of lifters extending in the axial direction are provided inside the outer peripheral wall. When the drum 8 is rotated during washing and drying, the laundry is lifted along the outer peripheral wall by the lifter and centrifugal force, and moves so as to fall by gravity. repeat. The rotation center axis of the drum 8 is inclined so that the horizontal or opening 8a side becomes higher.

  The cylindrical outer tub 10 includes the drum 8 coaxially, the front surface is opened, and a motor is attached to the center of the rear end surface. The rotation shaft of the motor passes through the outer tub 10 and is coupled to the drum 8. An outer tub cover 10a is provided at the opening on the front surface to enable water storage in the outer tub. In the center of the front side of the outer tub cover 10a, there is an opening 10b for taking in and out the laundry.

  The opening 10b and the opening provided in the front reinforcing member are connected by a rubber bellows 11, and the outer tub 10 is sealed with water by closing the door 2. A drain outlet is provided at the bottom bottom of the outer tub 10, and a drain hose is connected thereto. A drain valve is provided in the middle of the drain hose, and water is stored in the outer tub 10 by closing the drain valve and supplying water, and the drain valve is opened to drain the water in the outer tub 10 to the outside of the machine.

  The outer tub 10 shown in FIG. 3 is supported in a vibration-proof manner by a pair of left and right suspensions 12 having a lower side fixed to the base 1h. The suspension 12 includes a coil spring 13 and a damper 14. Moreover, the upper side of the outer tub 10 is supported by an auxiliary spring attached to the upper reinforcing member, and prevents the outer tub 10 from falling in the front-rear direction. A vibration sensor 15 is installed in the lower front part of the outer tub 10 as vibration detection means of the outer tub 10. Further, a gyro sensor 16 is installed on the vertical axis of the center of gravity of the vibrating portion such as the drum 8 and the outer tub 10. The vibration sensor 15 uses a triaxial sensor. The gyro sensor 16 as a rotation angle detection device also detects triaxial angular velocities. Here, the vibration sensor and the gyro sensor do not necessarily need to have three axes.

  FIG. 4 is a block diagram showing a control device of the drum type washing machine. The control device is composed mainly of the microcomputer 17. A laundry course or the like is selected by the input of the operation / display panel 3, and the operation determined by the activation pattern database 31 is started. A motor 19 is rotated via a motor drive circuit 18 in accordance with a command from the microcomputer 17. The rotation speed of the motor is measured by the rotation speed calculation unit 32. Further, the water supply valve 20 and the drain valve 21 are opened and closed according to the washing process.

  In the dehydration process, the vibration of the outer tub is detected by the vibration sensor 15 and the gyro sensor 16. The output of the gyro sensor 16 is converted into an angle by the rotation angle calculator 33. Further, the unbalance detection unit 34 calculates the unbalance position and amount from the vibration amplitude and the rotation angle. The calculated unbalance position and amount are compared with the threshold value database 35, and when it is determined that the unbalance amount is excessive, the rotation of the drum is stopped or decelerated.

  Next, a vibration determination method by angle detection according to the present invention will be described. A triaxial gyro sensor is installed in the outer tub and the rotation angle due to torsional vibration is measured. Depending on the unbalanced state, the rotation angle may be different even with the same vibration amplitude. When the rotation angle is large, vibration transmission to the floor and noise tend to be larger than when the rotation angle is small with the same vibration amplitude. Therefore, when the angular velocity (rotation angle) detected by the gyro sensor is larger than a preset value, the rotation of the drum is stopped or decelerated. By performing such control, vibration can be reduced.

  The vibration mode of the outer tub changes depending on the rotation speed of the drum. Since the axis of torsional vibration that appears prominently differs depending on the vibration mode, it is desirable to change the axis to be detected according to the rotational speed of the drum. Accordingly, it is necessary to change the vibration amplitude detection method. For example, in a mode in which the front side generated around 240 rpm vibrates left and right, it is desirable to measure the front left-right vibration and the rotation angle around the vertical axis.

  Next, the unbalance detection method of the present invention will be described. 5 and 6 show vibration amplitudes and rotation angles of two types of outer tanks having different unbalanced states. Here, the case of the vibration mode in which the front of the outer tub generated from 200 rpm to 300 rpm greatly shakes is taken as an example. FIG. 5 shows the left and right vibration amplitude and the rotation angle around the vertical axis when the unbalance is in the front and FIG. 6 is the unbalance in the rear.

  FIG. 5A is a schematic diagram showing an unbalanced position, and FIG. 5B is a diagram showing a vibration amplitude and a rotation angle in front and rear of 240 rpm. It can be seen that the front vibration is larger than the rear vibration because the front is unbalanced. Further, there is a difference in vibration amplitude between the front and rear of the outer tub, and the rotation angle is large. FIG. 6A is a schematic diagram showing the position of unbalance, and FIG. 6B is a diagram showing the vibration amplitude and the rotation angle at the front and rear of 240 rpm. Since there is an unbalance in the rear, the forward vibration is smaller than in the case where there is an unbalance in the front. Moreover, the vibration amplitude of the front and back of an outer tank is comparable, and a rotation angle becomes small. Thus, it can be seen that there is a difference in vibration amplitude and rotation angle depending on the position of unbalance.

  Next, FIG. 7 shows the relationship between the rotation angle and the vibration amplitude. The vertical axis represents the front left-right vibration amplitude, and the horizontal axis represents the rotation angle when the left-right vibration is the maximum value in one drum rotation. The rotation angle increases as the position of the unbalance moves forward. Moreover, the absolute value of the rotation angle increases as the unbalance amount increases. Therefore, these relations are recorded in advance as a table, an equation, or a map, and compared with the output of the vibration sensor and the gyro sensor or the value obtained by converting them into vibration amplitude and rotation angle, It is possible to detect the amount.

  In this embodiment, the method of estimating the unbalance amount from the relationship between the maximum value of the left and right vibration of 240 rpm and the rotation angle when the left and right vibration takes the maximum value has been described. It is also possible to estimate the unbalance position and amount from the maximum value of the left-right vibration and the phase difference between the left-right vibration and the rotation angle. In the above-described embodiment, the left-right vibration and the rotation angle around the vertical axis have been described as examples. However, the rotation direction may not be the vibration direction, and the rotation angle may be around the axis perpendicular to the vertical axis and the rotation axis of the drum.

  8 and 9 show flowcharts of the dehydration process of the present invention. FIG. 8 shows a low speed dewatering region, and FIG. 9 shows a high speed dewatering region.

First, at Step 101, the motor is driven to increase the rotational speed of the drum. In Step 102, the rotation angle determination 1 is performed in the drum rotation speed region A (80 rpm to 200 rpm). In the rotation speed region A, left and right vibrations appear greatly, so the detection direction of the rotation angle detection device is the rotation angle θ _y around the vertical axis. When the output θ _y of the rotation angle detecting device is larger than the preset threshold value θ _{1, the} process proceeds to Step 103, where the rotation of the drum is stopped or decelerated from the rotation speed at which the laundry sticks. On the other hand, if the rotation angle is smaller than θ ₁ , unbalance amount determination 1 is performed at Step 104. In the unbalance amount determination, the unbalance position and amount are detected from the vibration amplitude and the rotation angle. When the detected unbalance amount W is larger than the threshold value W ₁ set for each unbalance position in advance, the process proceeds to Step 103. Here, the threshold value is determined according to an unbalanced position.

Further, the rotation speed is increased, and rotation angle determination 2 is performed at Step 105 in the rotation speed region B (200 rpm to 300 rpm). In the rotation speed region B, forward left / right vibrations appear greatly, so the detection direction of the rotation angle detector is the rotation angle θ _y around the vertical axis. Further, since vertical vibrations are also generated, the rotation angle θ _x about the axis perpendicular to the rotation axis and the vertical axis of the drum is also detected. If the outputs θ _x and θ _{y of the} rotation angle detector are larger than the preset threshold values θ _x2 and θ _{y2, the} process proceeds to Step 103. On the other hand, if the rotation angle is smaller than θ _x2 and θ _y2 , unbalance amount determination 2 is performed in Step 106. Similarly to determine the location and amount of imbalance and Step 104, compared with a threshold value W ₂ set for each position of the previously unbalance the value, if greater than the threshold, the process proceeds to Step 103. If it is smaller than the threshold value W _{2, the} rotational speed is further increased.

A rotation angle determination 3 is performed in the rotation speed region C (300 rpm to 450 rpm) (Step 107). Because the rotational speed region C is longitudinal vibrations appear larger, the rotation angle theta _x about an axis perpendicular to the detection direction of the rotational angle detecting device in the rotation axis and the vertical axis of the drum. When the output θ _x of the rotation angle detection device is larger than the preset threshold value θ _{3, the} process proceeds to Step 103. On the other hand, when the rotation angle is smaller than θ ₃ , unbalance amount determination 3 is performed in Step 108. Similarly to determine the location and amount of imbalance and Step 104, compared with a threshold value W ₃ that is set for each position of the previously unbalance the value, if greater than the threshold W ₃ being the process proceeds to Step 103. If it is smaller than the threshold value W _{3, the} rotational speed is further increased.

The rotation angle determination 4 is performed in the rotation speed region D (450 rpm to 900 rpm) (Step 109). In the rotation speed region D, the detection direction of the rotation angle detection device is the rotation angle θ _y around the vertical axis. When the output θ of the rotation angle detection device is larger than the preset threshold value θ _{4, the} process proceeds to Step 103. On the other hand, when the rotation angle is smaller than θ ₄ , the unbalance amount determination 4 is performed at Step 110. Similarly to determine the location and amount of imbalance and Step 104, is compared with the threshold value W ₄ that is set for each position of the previously unbalance the value, if greater than the threshold W ₃ being the process proceeds to Step 103. If it is smaller than the threshold value W _{4, the} rotational speed is further increased and the process proceeds to the high speed dewatering region.

  Here, in this embodiment, the unbalance amount determination is performed in each rotation speed region, but it is not necessarily performed in all regions, and it is assumed that the unbalance amount does not change greatly when the rotation speed is increased, The determination may be made only in the rotation speed region A or the rotation speed region B.

Next, a method for controlling the high-speed dewatering region will be described with reference to FIG. In Step 201, the rotation speed is increased, and in Step 202, the rotation angle determination 5 is performed. When the output of the rotation angle detection device is larger than the preset threshold value θ ₅ , the process proceeds to Step 203 and the dehydration rotation speed and the dehydration time are determined based on the rotation speed at the time of the shift. For example, when shifting to Step 203 at 1200 rpm, the rotational speed is 1200 rpm and the dehydration time is 15 minutes.

If the output of the rotation angle detection device is equal to or smaller than the preset threshold value θ ₅ in Step 202, the process proceeds to Step 204 and unbalance amount determination 5 is performed. Here, when the output of the vibration detection device is larger than the preset threshold value W ₅ , the process proceeds to Step 205 to set the dewatering rotation speed and the dewatering time. When the output of the vibration detection device is equal to or less than the preset threshold value W ₅ , the process proceeds to Step 206. In Step 206, it is determined whether or not the drum rotation speed has reached the final dewatering rotation speed ω set in advance according to the amount of laundry and the course. If the rotation speed is equal to or less than ω, the process proceeds to Step 202. When the final dewatering rotation speed ω has been reached, the process proceeds to Step 207, where the rotation speed is maintained until the dewatering time reaches a predetermined dewatering time. To complete.

  In the above-described embodiment, only the rotation angle of one axis is detected according to the rotation speed, but more accurate detection is possible by detecting all three axes.

  Next, a vibration estimation method will be described. In the case of a drum type washing machine, the vibration mode differs depending on the rotational speed of the drum, so the position and direction that need to be measured are different. For example, in the vicinity of 150 rpm, the rear of the outer tub is in a mode that swings greatly to the left and right, and the left and right ends of the rear of the outer tub may collide with the housing. On the other hand, in the vicinity of 300 rpm, the outer tub vibrates back and forth, and the upper rear part of the outer tub may collide with the housing. Thus, the position and vibration direction of the outer tub that needs to be detected vary depending on the rotational speed of the drum. However, the place where the detection is necessary is basically a small space, and it is difficult to install the sensor. Further, since there are a plurality of positions that need to be detected, there is a problem that the number of necessary sensors increases and the cost increases. Therefore, this problem can be solved by estimating the vibration amplitude at the position where detection is required from the output of a sensor installed at a location different from the position where detection is necessary.

FIG. 10 is a schematic diagram showing the vibration of the outer tub and the vibration detection direction. A sensor is installed in the lower part of the front, the front-rear displacement of the position is X _f, and the rotation angle about the axis perpendicular to the paper surface is θ. In addition, the depth of the outer tub is L and the height is H. At this time, the longitudinal displacement _Xb at the upper rear is _Xb = _Xf + L (cos [theta] -1) + Hsin [theta].
Can be expressed as Thus, the vibration amplitude at each position of the outer tub can be estimated from the outputs of the vibration sensor and the gyro sensor installed at one place. Further, by changing the position and direction in which vibration is estimated according to the rotation speed of the drum, vibration of the outer tub and the casing can be prevented, and a quiet dehydration operation can be provided.

  Next, a method for installing the vibration detection device and the rotation angle detection device will be described. The output of the rotation angle detection device may differ depending on whether it is installed on the rotation axis or at a position away from the rotation axis, and becomes more susceptible to noise as it moves away from the rotation axis. Moreover, when installing in the position away from a rotating shaft, not only rotational vibration but translational vibration generate | occur | produces, There exists a possibility that the lifetime of an apparatus may fall. Thus, it is desirable to install the rotation angle detection device near the rotation center and the center of gravity of the vibrating body to be measured.

  In addition, a 3-axis acceleration sensor and a 3-axis gyro sensor are performed on a single chip by MEMS (Micro Electro Mechanical Systems), etc., and the substrate is shared by installing them at the same position as the vibration detection device and the rotation angle detection device. It is possible to reduce the cost. Since the outer tub and the casing are connected to each other with rubber packing, the force transmitted to the casing increases when the forward vibration is large. In addition, it is important to grasp the forward vibration because the forward vibration affects the life of the packing. Therefore, when the vibration detection device and the rotation angle detection device are installed at the same position as described above, it is desirable to install the vibration detection device and the rotation angle detection device in front of the center of gravity of the vibration body.

  Although the drum type washing machine has been described in the present embodiment, the same applies to the vertical washing machine and the like.

DESCRIPTION OF SYMBOLS 1 Case 2 Door 3 Operation / display panel 5 Operation switch 6 Indicator 7 Control device 8 Drum 10 Outer tank 15 Vibration sensor 16 Gyro sensor

Claims (7)

In a washing machine provided with a drum for storing laundry, an outer tub containing the drum, a drive mechanism for rotationally driving the drum, and a control device for controlling the drive mechanism,
It has detection means for measuring the magnitude of torsional vibration of at least one of the circumference of the vertical axis and the axis perpendicular to the rotation axis of the drum, and the rotation of the drum is controlled based on the output of the detection means. Features a washing machine. In claim 1,
The detection means is a rotation angle detection device, and the rotation of the drum is controlled when the output of the rotation angle detection device is larger than a preset threshold value. The washing machine according to claim 1,
A washing machine, wherein a detection direction of a rotation angle detection device is changed according to a rotation speed of a drum. The washing machine according to claim 1,
Having a vibration detection device for detecting the vibration of the outer tub,
A washing machine that controls the rotation of the drum based on an output of the vibration detecting means and an output of the rotation angle detecting device. The washing machine according to claim 4,
An unbalance position specifying means for detecting an unbalance position and amount based on an output of the vibration detection device and an output of the rotation angle detection device is provided, and the rotation of the drum is controlled according to the unbalance position. Washing machine. The washing machine according to claim 4,
A washing machine that detects an unbalanced position based on a phase difference between vibration components of the vibration detection device and the rotation angle detection device. A vibration for detecting vibration of the outer tub in a washing machine including a drum for storing laundry, an outer tub for containing the drum, a driving mechanism for rotationally driving the drum, and a control device for controlling the driving mechanism A detection device, and a rotation angle detection device for measuring the rotation angle of the outer tub,
The vibration amplitude at a position where no vibration detection device is installed is estimated from the outputs of the vibration detection device and the rotation angle detection device, and if the vibration amplitude is larger than a preset threshold value, the rotation speed of the drum is set. A washing machine characterized by controlling.

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