US20180155862A1 - Dewatering Machine - Google Patents

Dewatering Machine Download PDF

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Publication number
US20180155862A1
US20180155862A1 US15/576,592 US201615576592A US2018155862A1 US 20180155862 A1 US20180155862 A1 US 20180155862A1 US 201615576592 A US201615576592 A US 201615576592A US 2018155862 A1 US2018155862 A1 US 2018155862A1
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US
United States
Prior art keywords
duty ratio
dewatering
washings
rotating speed
motor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US15/576,592
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English (en)
Inventor
Tomonari Kawaguchi
Hiroki Sato
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Qingdao Haier Washing Machine Co Ltd
Aqua Co Ltd
Original Assignee
Qingdao Haier Washing Machine Co Ltd
Aqua Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Qingdao Haier Washing Machine Co Ltd, Aqua Co Ltd filed Critical Qingdao Haier Washing Machine Co Ltd
Priority claimed from PCT/CN2016/083395 external-priority patent/WO2016188437A1/zh
Publication of US20180155862A1 publication Critical patent/US20180155862A1/en
Assigned to QINGDAO HAIER WASHING MACHINE CO., LTD., AQUA CO., LTD. reassignment QINGDAO HAIER WASHING MACHINE CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KAWAGUCHI, TOMONARI, SATO, HIROKI
Abandoned legal-status Critical Current

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    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F34/00—Details of control systems for washing machines, washer-dryers or laundry dryers
    • D06F34/14—Arrangements for detecting or measuring specific parameters
    • D06F34/16—Imbalance
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F23/00—Washing machines with receptacles, e.g. perforated, having a rotary movement, e.g. oscillatory movement, the receptacle serving both for washing and for centrifugally separating water from the laundry 
    • D06F23/04—Washing machines with receptacles, e.g. perforated, having a rotary movement, e.g. oscillatory movement, the receptacle serving both for washing and for centrifugally separating water from the laundry  and rotating or oscillating about a vertical axis
    • D06F33/02—
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F33/00—Control of operations performed in washing machines or washer-dryers 
    • D06F33/30—Control of washing machines characterised by the purpose or target of the control 
    • D06F33/32—Control of operational steps, e.g. optimisation or improvement of operational steps depending on the condition of the laundry
    • D06F33/40—Control of operational steps, e.g. optimisation or improvement of operational steps depending on the condition of the laundry of centrifugal separation of water from the laundry
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F35/00—Washing machines, apparatus, or methods not otherwise provided for
    • D06F35/005—Methods for washing, rinsing or spin-drying
    • D06F35/007—Methods for washing, rinsing or spin-drying for spin-drying only
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F2103/00—Parameters monitored or detected for the control of domestic laundry washing machines, washer-dryers or laundry dryers
    • D06F2103/02—Characteristics of laundry or load
    • D06F2103/04—Quantity, e.g. weight or variation of weight
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F2103/00—Parameters monitored or detected for the control of domestic laundry washing machines, washer-dryers or laundry dryers
    • D06F2103/26—Imbalance; Noise level
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F2105/00—Systems or parameters controlled or affected by the control systems of washing machines, washer-dryers or laundry dryers
    • D06F2105/46—Drum speed; Actuation of motors, e.g. starting or interrupting
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F2105/00—Systems or parameters controlled or affected by the control systems of washing machines, washer-dryers or laundry dryers
    • D06F2105/62—Stopping or disabling machine operation
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F34/00—Details of control systems for washing machines, washer-dryers or laundry dryers
    • D06F34/28—Arrangements for program selection, e.g. control panels therefor; Arrangements for indicating program parameters, e.g. the selected program or its progress
    • D06F34/32—Arrangements for program selection, e.g. control panels therefor; Arrangements for indicating program parameters, e.g. the selected program or its progress characterised by graphical features, e.g. touchscreens
    • D—TEXTILES; PAPER
    • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
    • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
    • D06F35/00—Washing machines, apparatus, or methods not otherwise provided for
    • D06F35/005—Methods for washing, rinsing or spin-drying

Definitions

  • the present disclosure relates to a dewatering machine.
  • a patent literature 1 discloses a washing machine with a dewatering function. During the dewatering of washings in the washing machine, a motor, which rotates a washing and dewatering drum accommodating the washings and to which a voltage with a controlled duty ratio is applied, rotates at a constant speed of 120 rpm, then rotates at a constant speed of 240 rpm, and finally rotates at a constant speed of 800 rpm.
  • the duty ratio at a time point when 3.6 seconds are elapsed after the motor starts to accelerate from 120 rpm to 240 rpm is taken as a reference duty ratio.
  • a target value related to the duty ratio which changes over time in a state that the motor rotates at the constant speed of 240 rpm is used as a comparative duty ratio and is calculated based on the reference duty ratio.
  • a difference between an actual duty ratio obtained once at every specified timing and the comparative duty ratio at the same timing in the state where the motor rotates at the constant speed of 240 rpm is greater than a specified threshold value, it is determined that the washings are biased, and the rotation of the motor is stopped.
  • Patent Literature 1 Japanese Laid-Open Patent Publication No. 2011-240040
  • the washing machine in the patent literature 1 determines that a rotating speed of the motor reaches 240 rpm at the time point when 3.6 seconds are elapsed after the motor starts to accelerate from 120 rpm to 240 rpm, and the duty ratio at the time point is regarded as the reference duty ratio.
  • time required for the rotating speed of the motor to reach 240 rpm may change based on the load of the washings in the washing and dewatering drum, the time is not necessarily limited to the above 3.6 seconds.
  • the reference duty ratio is an important factor which affects accuracy for detecting whether the washings are biased.
  • the duty ratio at the time point when 3.6 seconds are elapsed after the motor starts to accelerate is always regarded as the reference duty ratio, irrespective of the load. Therefore, the reference duty ratio, which is a duty ratio acquired at timing deviating from the correct timing due to the influence of the load, has an negative impact on the accuracy for detecting whether the washings are biased.
  • the present disclosure is a dewatering machine completed in the background described above, and aims at providing a dewatering machine capable of improving detection accuracy of bias of washings.
  • the present disclosure also aims at providing a dewatering machine capable of shortening duration of dewatering operation.
  • the present disclosure provides a dewatering machine, including: a dewatering drum for accommodating washings and rotating to dewater the washings; an electric motor for rotating the dewatering drum; a load measuring unit for measuring a load of the washings in the dewatering drum when the dewatering drum begins to rotate; a drive control unit for, after the load measuring measures the load, rotating the motor constantly at a first rotating speed by controlling a duty ratio of a voltage applied to the motor and then rotating the motor constantly at a second rotating speed higher than the first rotating speed so as to dewater the washings formally; an acquisition unit for acquiring the duty ratio of the voltage applied to the motor as a reference duty ratio in an acceleration state in which the motor accelerates to the first rotating speed; a timing determination unit for determining timing for the acquisition unit to acquire the reference duty ratio; a determination unit for determining whether the washings in the dewatering drum are biased or not according to an index indicating a change between a duty ratio of the voltage applied to the motor to maintain the first rotating speed and the reference duty ratio within
  • the dewatering machine includes an execution unit for, in a case where the stopping control unit enables the dewatering drum to stop rotating, executing one of the following executions: a rotation of the dewatering drum for restart the dewatering of the washings and a processing for correcting the bias of the washings in the dewatering drum.
  • the drive control unit rotates the motor constantly at a specified speed lower than the first rotating speed, and the execution unit shortens the duration in which the motor rotates constantly at the specified speed in a case where the execution unit executes the rotation of the dewatering drum for restart the dewatering of the washings.
  • a dewatering machine including: a dewatering drum for accommodating washings and rotating to dewater the washings; an electric motor for rotating the dewatering drum; a drive control unit for rotating the motor constantly at a first rotating speed by controlling a duty ratio of a voltage applied to the motor and then rotating the motor constantly at a second rotating speed higher than the first rotating speed so as to dewater the washings formally; an acquisition unit for acquiring a duty ratio every a specified time within a specified period after the motor begins to accelerate to the first rotating speed; a counting unit for adding 1 to a count value with an initial value of zero when the duty ratio acquired by the acquisition unit is greater than or equal to the duty ratio acquired last time and resetting the count value to the initial value when the duty ratio acquired by the acquisition unit is smaller than the duty ratio acquired last time; a determination unit for determining that the washings in the dewatering drum are biased when the count value is greater than or equal to a specified threshold; and a stopping control unit for stopping the rotation of the dewatering
  • a dewatering machine including: a dewatering drum for accommodating washings and rotating to dewater the washings; an electric motor for rotating the dewatering drum; a drive control unit for rotating the motor constantly at a first rotating speed by controlling a duty ratio of a voltage applied to the motor and then rotating the motor constantly at a second rotating speed higher than the first rotating speed so as to dewater the washings formally; an acquisition unit for acquiring a duty ratio every a specified time within a period when the rotating speed of the motor accelerates from the first rotating speed to a second rotating speed; a determination unit for determining that the washings in the dewatering drum are biased when the duty ratio acquired by the acquisition unit is greater than or equal to a specified threshold; a stopping control unit for stopping the rotation of the dewatering drum in a case where the determination unit determines that the washings are biased; a receiving unit for receiving a selection related to a dewatering condition of the washings; and a threshold changing unit for changing the threshold according to the selection related to the selection related to the
  • the present disclosure provides a dewatering machine, including: a dewatering drum for accommodating washings and rotating to dewater the washings; an electric motor for rotating the dewatering drum; a drive control unit for rotating the motor constantly at a first rotating speed by controlling a duty ratio of a voltage applied to the motor and then rotating the motor constantly at a second rotating speed higher than the first rotating speed so as to dewater the washings formally; an acquisition unit for acquiring a maximum value of a duty ratio in an acceleration state in which the motor accelerates to the first rotating speed to serve as a maximum duty ratio; a calculation unit for calculating an accumulated value of a difference between the duty ratio in every specified time and the maximum duty ratio after the acquisition unit acquires the maximum duty ratio; a determination unit for determining that the washings in the dewatering drum are biased when the accumulated value is smaller than the specified threshold; and a stopping control unit for stopping the rotation of the dewatering drum in a case where the determination unit determines that the washings are biased.
  • the threshold value is calculated using an equation adopting a count value and the maximum duty ratio as variables, wherein the count value is added by 1 once every the specified time.
  • the drive control unit controls the duty ratio in the following way: in the acceleration state in which the motor accelerates to the first rotating speed, the drive control unit generates the maximum duty ratio when the rotating speed is slightly lower than a rotating speed at which the dewatering drum resonates.
  • the dewatering machine performing the dewatering operation controls the duty ratio of the voltage applied to the electric motor which rotates the dewatering drum, the motor rotates constantly at the first rotating speed, and then the motor rotates constantly at the second rotating speed higher than the first rotating speed.
  • the washings in the dewatering drum are dewatered formally.
  • the reference duty ratio is acquired by the acquisition unit in an acceleration state in which the motor accelerates to the first rotating speed. Then, after the acquisition unit acquires the reference duty ratio, within a specified period, whether the washings in the dewatering drum are biased or not is determined according to an index indicating the change between the duty ratio of the voltage applied to the motor to maintain the first rotating speed and the reference duty ratio. In the case where the washings are determined to be biased, the rotation of the dewatering drum is stopped.
  • a detection step of the bias when the dewatering drum begins to rotate, a load of the washings in the dewatering drum is measured, and a timing determination unit determines timing for the acquisition unit to acquire the reference duty ratio according to the measured load.
  • the detection of the bias of the washings can be accurately executed on the basis of the reference duty ratio. The result is that the accuracy for detecting whether the washings are biased is improved.
  • either of the rotation of the dewatering drum for restart the dewatering of the washings and the processing for correcting the bias of the washings in the dewatering drum can be selectively executed according to the index indicating the change between the duty ratio between the reference duty ratio.
  • the processing for correcting the bias of the washings is not necessarily executed. Therefore, when the index is an index indicating that the washings are slightly biased, the dewatering drum is immediately rotated so as to restart the dewatering, thereby shortening the dewatering operation time.
  • the dewatering operation including a step of rotating the motor constantly at the specified speed lower than the first rotating speed
  • the dewatering drum for restart the dewatering of the washings since the duration of the step is shortened, the dewatering time is further shortened.
  • the dewatering machine performing the dewatering operation controls the duty ratio of the voltage applied to the electric motor which rotates the dewatering drum, the motor rotates constantly at the first rotating speed, and then the motor rotates constantly at the second rotating speed higher than the first rotating speed.
  • the washings in the dewatering drum are dewatered formally.
  • a duty ratio is acquired every a specified time within a specified period, and each duty ratio is compared with the duty ratio acquired last time. Specifically, when the acquired duty ratio is greater than or equal to the duty ratio acquired last time, the count value with an initial value of zero is added by 1, and when the acquired duty ratio is smaller than the duty ratio acquired last time, the count value is reset to the initial value.
  • the washings in the dewatering drum are determined to be biased, and the rotation of the dewatering drum is stopped.
  • the accurate detection for acquiring the change of the duty ratio during the detection in real time can also be performed, so that the accuracy for detecting whether the washings are biased can be improved.
  • the dewatering machine performing the dewatering operation controls the duty ratio of the voltage applied to the electric motor which rotates the dewatering drum, the motor rotates constantly at the first rotating speed, and then the motor rotates constantly at the second rotating speed higher than the first rotating speed.
  • the washings in the dewatering drum are dewatered formally.
  • a duty ratio is acquired every the specified timing.
  • the duty ratio is greater than or equal to the specified threshold, the washings in the dewatering drum are determined to be biased, and the rotation of the dewatering drum is stopped.
  • the dewatering machine may receive a selection related to a dewatering condition of the washings via the receiving unit and may change the threshold according to the received dewatering condition.
  • the bias of the washings can be detected through the threshold adaptive to the dewatering condition in the dewatering operation under various dewatering conditions, the accuracy for detecting whether the washings are biased can be improved.
  • the dewatering machine operates the dewatering operation controls the duty ratio of the voltage applied to the electric motor which rotates the dewatering drum, the motor rotates constantly at the first rotating speed, and then the motor rotates constantly at the second rotating speed higher than the first rotating speed.
  • the washings in the dewatering drum are dewatered formally.
  • a maximum value of the duty ratio is acquired to serve as the maximum duty ratio in the acceleration state where the motor accelerates to the first rotating speed, and then an accumulated value of the difference between the maximum duty ratio and the duty ratio of every specified timing is calculated.
  • the threshold value is calculated using an equation adopting the count value added by 1 once every the specified timing and the maximum duty ratio as variables.
  • the maximum duty ratio varies according to the load of the washings in the dewatering drum. Therefore, the threshold value is set differently according to the load. Thus, since whether the washings are biased is detected according to the optimum threshold corresponding to the load of the washings in the dewatering drum, false detection can be prevented. Therefore, the accuracy for detecting whether the washings are biased is further improved.
  • the duty ratio is set in such a manner that the maximum duty ratio is generated when the rotating speed is slightly lower than the rotating speed at which the dewatering drum resonates. At this moment, the resonance occurs early after the maximum duty ratio is generated. Therefore, a phenomenon that the accumulated value is difficult to increase appears soon. Hence, the bias of the washings in the dewatering drum can be early and correctly detected.
  • FIG. 1 is a schematic longitudinal sectional right view illustrating a dewatering machine 1 of an embodiment of the present disclosure
  • FIG. 2 is a block diagram illustrating an electric structure of a dewatering machine 1 .
  • FIG. 3 is a time chart illustrating a state of a rotating speed of a motor 6 in a dewatering operation implemented by a dewatering machine 1 .
  • FIG. 4 is a diagram illustrating a relationship between a weight of washings accommodated in a dewatering drum 4 of a dewatering machine 1 and a load detected by a dewatering machine 1 according to the weight of the washings;
  • FIG. 5A is a flow chart illustrating an outline of detections 1 to 4 for detecting whether washings in a dewatering drum 4 are biased in dewatering operation;
  • FIG. 5B is a flow chart illustrating an outline of detections 1 to 4 for detecting whether washings in a dewatering drum 4 are biased in dewatering operation;
  • FIG. 6A is a flow chart illustrating control actions related to detections 1 and 2 ;
  • FIG. 6B is a flow chart illustrating control actions related to detections 1 and 2 ;
  • FIG. 7 is a graph illustrating a relationship between a rotating speed of a motor 6 and a difference Sn of a rotating speed in association with detection 1 ;
  • FIG. 8 is a graph illustrating a relationship between a rotating speed of a motor 6 and an accumulated value U of an absolute value of a difference about a difference S in association with detection 2 ;
  • FIG. 9A is a flow chart illustrating control actions related to detections 3 and 4 ;
  • FIG. 9B is a flow chart illustrating control actions related to detections 3 and 4 ;
  • FIG. 10 is a graph illustrating a relationship between time and a first count value E in association with detection 3 ;
  • FIG. 11 is a graph illustrating a relationship between time and a corrected duty ratio dn_diff in association with detection 4 ;
  • FIG. 12 is a flow chart illustrating an outline of detections 5 - 1 and 5 - 2 for detecting whether washings in a dewatering drum 4 are biased in dewatering operation;
  • FIG. 13 is a flow chart illustrating control actions related to detection 5 - 1 ;
  • FIG. 14 is a graph illustrating a relationship between a rotating speed and a moving accumulated value Cn in association with detections 5 - 1 and 5 - 2 ;
  • FIG. 15 is a flow chart illustrating control actions related to detection 5 - 2 ;
  • FIG. 16 is a flow chart illustrating a control action of detecting foam in dewatering operation
  • FIG. 17 is a time chart illustrating a state of a rotating speed of a motor 6 during dewatering operation implemented by a dewatering machine 1 in association with detection 6 ;
  • FIG. 18 is a flow chart illustrating control actions related to detection 6 ;
  • FIG. 19 is a graph illustrating a relationship between a count value G and an accumulated value H in association with detection 6 ;
  • FIG. 20 is a graph illustrating a relationship between a count value G and a duty ratio in association with detection 6 .
  • FIG. 1 is a schematic longitudinal sectional right view illustrating a dewatering machine 1 of an embodiment of the present disclosure.
  • An up-down direction in FIG. 1 is called as an up-down direction X of a dewatering machine 1
  • a left-right direction in FIG. 1 is called as a front-rear direction Y of the dewatering machine 1
  • the dewatering machine 1 is schematically described.
  • an up direction is called as an upper side X 1
  • a down direction is called as a lower side X 2
  • a left direction in FIG. 1 is called as a front direction Y 1
  • a right direction in FIG. 1 is called as a rear direction Y 2 .
  • the dewatering machine 1 includes all apparatuses capable of carrying out dewatering operation of washings Q. Therefore, the dewatering machine 1 not only includes an apparatus having a dewatering function, but also includes a washing machine having a dewatering function and a washing and drying machine.
  • the dewatering machine 1 is described below by taking the washing machine as an example.
  • the dewatering machine 1 includes a housing 2 , an outer drum 3 , a dewatering drum 4 , a rotary wing 5 , an electric motor 6 , and a transmission mechanism 7 .
  • the housing 2 is made of, e.g., metal, and formed in a box shape.
  • An upper surface 2 A of the housing 2 is formed obliquely relative to the front-rear direction Y in a manner of extending to the upper side X 1 toward the rear direction Y 2 .
  • An opening 8 connecting the inside and outside of the housing 2 is formed in the upper surface 2 A.
  • a door 9 for opening and closing the opening 8 is arranged on the upper surface 2 A.
  • An operation part 20 consisting of a liquid crystal operation panel and the like is arranged in a region toward the front direction Y 1 than the opening 8 on the upper surface 2 A. A user can operate the operation part 20 to select a dewatering condition freely, or instruct the dewatering machine 1 to start or to stop.
  • the outer drum 3 is made of, e.g., resin, and formed in a bottomed cylindrical shape.
  • the outer drum 3 has a substantially cylindrical circumferential wall 3 A arranged along the up-down direction X; a bottom wall 3 B, configured to block a hollow part of the circumferential wall 3 A from the lower side X 2 ; and an annular wall 3 C, which is annular and protrudes towards a circle center side of the circumferential wall 3 A while covering an edge at a side of the upper side X 1 of the circumferential wall 3 A.
  • An outlet-inlet 10 communicated with the hollow part of the circumferential wall 3 A from the upper side X 1 is formed inside the annular wall 3 C.
  • the outlet-inlet 10 is arranged in opposite and communicated state relative to the opening 8 of the housing 2 from the lower side X 2 .
  • a door 11 for opening and closing the outlet-inlet 10 is arranged on the annual wall 3 C.
  • the bottom wall 3 B is formed in a circular plate shape in a manner of substantially extending horizontally.
  • a through hole 3 D penetrating through the bottom wall 3 B is formed in a position of the circle center of the bottom wall 3 B.
  • Water can be stored in the outer drum 3 .
  • a water supply pipeline 12 connected with a faucet of tap water is connected with the outer drum 3 from the upper side X 1 , and the tap water is supplied into the outer drum 3 from the water supply pipeline 12 .
  • a water supply valve 13 which can be opened and closed to start or stop water supply is arranged in a midway of the water supply pipeline 12 .
  • a drainage pipeline 14 is connected with the outer drum 3 from the lower side X 2 , and the water in the outer drum 3 is discharged outside the washing machine from the drainage pipeline 14 .
  • a drainage valve 15 which can be opened and closed to start or stop drainage is arranged in a midway of the drainage pipeline 14 .
  • the dewatering drum 4 is made of, e.g., metal, and is formed in a bottomed cylindrical shape which is a circle smaller than the outer drum 3 , and can accommodate washings Q.
  • the dewatering drum 4 has a substantially cylindrical circumferential wall 4 A arranged along the up-down direction X and a bottom wall 4 B configured to block a hollow part of the circumferential wall 4 A from the lower side X 2 .
  • An internal circumferential surface of the circumferential wall 4 A is an internal circumferential surface of the dewatering drum 4 .
  • An upper end part of the internal circumferential surface of the circumferential wall 4 A is an outlet-inlet 21 for enabling the hollow part of the circumferential wall 4 A to expose to the upper side X 1 .
  • the outlet-inlet 21 is arranged in opposite and communicated state relative to the outlet-inlet 10 of the outer drum 3 from the lower side X 2 .
  • the outlet-inlet 10 and the outlet-inlet 21 are opened and closed through the door 11 together.
  • a user of the dewatering machine 1 puts the washings Q in the dewatering drum 4 and takes the washings Q out of the dewatering drum 4 through the opened opening 8 , the outlet-inlet 10 and the outlet-inlet 21 .
  • the dewatering drum 4 is coaxially accommodated in the outer drum 3 .
  • the dewatering drum 4 accommodated in the outer drum 3 can rotate around an axis 16 which forms a central axis and extends in the up-down direction X.
  • a plurality of through holes which are not shown, are formed in the circumferential wall 4 A and the bottom wall 4 B of the dewatering drum 4 , and the water in the outer drum 3 can flow between the outer drum 3 and the dewatering drum 4 through the through holes. Therefore, a water level in the outer drum 3 is consistent with a water level in the dewatering drum 4 .
  • the bottom wall 4 B of the dewatering drum 4 is spaced from the bottom wall 3 B of the outer tank 3 toward the upper side X 1 and is formed in a circular plate shape extending substantially parallel.
  • a through hole 4 C penetrating through the bottom wall 4 B is formed in a position of a circle center of the bottom wall 4 B consistent with the axis 16 .
  • a tubular supporting shaft 17 surrounding the through hole 4 C and stretching out to the lower side X 2 along the axis 16 is arranged on the bottom wall 4 B.
  • the supporting shaft 17 is inserted into the through hole 3 D of the bottom wall 3 B of the outer drum 3 , and a lower end part of the supporting shaft 17 is located closer to the lower side X 2 relative to the bottom wall 3 B.
  • the rotary wing 5 i.e., an impeller, is formed in a discoid shape by taking the axis 16 as a circle center, and is arranged concentrically with the dewatering drum 4 along the bottom wall 4 B in the dewatering drum 4 .
  • a plurality of blades 5 A radially disposed are arranged on an upper surface of the rotary wing 5 toward the outlet-inlet 21 of the dewatering drum 4 .
  • a rotating shaft 18 extending toward the lower side X 2 from a circle center of the rotary wing 5 along the axis 16 is arranged on the rotary wing 5 .
  • the rotating shaft 18 is inserted into a hollow part of the supporting shaft 17 , and a lower end part of the rotating shaft 18 is located closer to the lower side X 2 relative to the bottom wall 3 B of the outer drum 3 .
  • the motor 6 is implemented through a variable frequency motor.
  • the motor 6 is arranged in the lower side X 2 of the outer drum 3 in the housing 2 , and is provided with an output shaft 19 rotating around the axis 16 .
  • a transmission mechanism 7 is located between the lower end parts of both the supporting shaft 17 and the rotating shaft 18 , and an upper end part of the output shaft 19 .
  • the transmission mechanism 7 selectively transmits a driving force outputted by the motor 6 from the output shaft 19 to one or both of the supporting shaft 17 and the rotating shaft 18 .
  • a widely known transmission mechanism can be taken as the transmission mechanism 7 .
  • the dewatering drum 4 and the rotary wing 5 rotate around the axis 16 when the driving force from the motor 6 is transmitted to the supporting shaft 17 and the rotating shaft 18 .
  • the washings Q in the dewatering drum 4 are stirred through the rotating dewatering drum 4 and the blades 5 A of the rotary wing 5 during washing and rinsing.
  • the washings Q in the dewatering drum 4 are dewatered through high-speed integrated rotation of the dewatering drum 4 and the rotary wing 5 during dewatering after the rinsing.
  • FIG. 2 is a block diagram illustrating an electric structure of a dewatering machine 1 .
  • the dewatering machine 1 includes: a load measuring unit, a drive control unit, an acquisition unit, a timing determination unit, a determination unit, a stopping control unit, an execution unit, a counting unit, a receiving unit, a threshold value changing unit and a control part 30 as a calculation unit.
  • the control part 30 is disposed in the housing 2 (referring to FIG. 1 ) and includes, for example, a CPU 31 ; a memory 32 such as ROM or RAM; a timer 35 ; and a microcomputer as a counter 34 .
  • the dewatering machine 1 further includes a water level sensor 33 and a rotating speed reading apparatus 34 .
  • the water level sensor 33 , the rotating speed reading apparatus 34 , the motor 6 , the transmission mechanism 7 , the water supply valve 13 , the drainage valve 15 and the operation part 20 are electrically connected with the control part 30 respectively.
  • the water level sensor 33 is a sensor for detecting the water levels of the outer drum 3 and of the dewatering drum 4 , and a detection result of the water level sensor 33 is inputted into the control part 30 in real time.
  • the rotating speed reading apparatus 34 is an apparatus for reading a rotating speed of the motor 6 , and strictly speaking, for reading a rotating speed of the output shaft 19 of the motor 6 , and consists of, e.g., a Hall integrated circuit (IC).
  • the rotating speed read by the rotating speed reading apparatus 34 is inputted into the control part 30 in real time.
  • the control part 30 controls a duty ratio of a voltage applied to the motor 6 according to the inputted rotating speed, and then, enables the motor 6 to rotate at a desired rotating speed.
  • the control part 30 switches a transmission target of the driving force of the motor 6 to one or both of the supporting shaft 17 and the rotating shaft 18 by controlling the transmission mechanism 7 .
  • the control part 30 controls the opening and closing of the water supply valve 13 and the drainage valve 15 . As mentioned above, when the user selects the dewatering condition and the like of the washings Q by operating the operating part 20 , the control part 30 receives the selection.
  • FIG. 3 is a time chart illustrating a state of a rotating speed of a motor 6 in dewatering operation implemented by a dewatering machine 1 .
  • a horizontal axis indicates elapsed time
  • a vertical axis indicates a rotating speed of the motor 6 (unit: rpm).
  • the control part 30 measures the load of the washings Q in the dewatering drum 4 when the dewatering drum 4 begins to rotate. After the load is measured, the control part 30 enables the motor 6 to rotate at a constant speed of 120 rpm after the rotating speed of the motor 6 is increased to 120 rpm. Then the control part 30 enables the motor 6 to rotate at a constant speed of 240 rpm after the rotating speed of the motor 6 is increased from 120 rpm to 240 rpm. Then the control part 30 enables the motor 6 to rotate at a constant speed of 800 rpm after the rotating speed of the motor 6 is increased from 240 rpm to 800 rpm.
  • the washings Q in the dewatering drum 4 are formally dewatered. It shall be noted that during the dewatering operation, when the rotating speed of the motor 6 is, for example, comprised between 50 rpm and 60 rpm, the dewatering drum 4 resonates horizontally, and when the rotating speed of the motor 6 is, for example, comprised between 200 rpm and 220 rpm, the dewatering drum 4 resonates longitudinally.
  • the washings Q in the dewatering drum 4 are in a state of being biased and arranged in the circumferential direction of the dewatering drum 4 , the washings Q are biased in the dewatering drum 4 .
  • the dewatering drum 4 performs eccentric rotation.
  • the dewatering drum 4 may swing widely, as such the dewatering machine 1 vibrate significantly and produce noise.
  • control part 30 detects whether the washings Q in the dewatering drum 4 are biased during the dewatering operation, and stops the motor 6 when the washings Q are detected to be biased. In such detection, the control part 30 performs five types of electric detections, i.e., detection 1 , detection 2 , detection 3 , detection 4 and detection 5 .
  • the detections 1 to 4 are executed in a low-speed eccentricity detection section, and the low-speed eccentricity detection section includes an acceleration period where the rotating speed of the motor 6 is increased from 120 rpm to 240 rpm and a specified period after the motor 6 begins to accelerate to 240 rpm.
  • the detection 5 is executed in a period where the rotating speed of the motor 6 reaches 800 rpm from 240 rpm, i.e., a high-speed eccentricity detection section.
  • FIG. 4 is a graph illustrating a relationship between the weight and the load of the washings Q accommodated in the dewatering drum 4 , and the load is detected by the dewatering machine 1 according to the weight of the washings Q.
  • the horizontal axis indicates the weight (unit: kg) of the washings Q
  • the longitudinal axis indicates a detection value of the load.
  • the control part 30 measures the load of the washings Q in the dewatering drum 4 when the dewatering drum 4 begins to rotate.
  • the control part 30 enables the dewatering drum 4 to rotate at the specified rotating speed when the dewatering drum 4 begins to rotate, and detects a value obtained after accumulating the duty ratio of the voltage applied to the motor 6 at this moment for a given times as the load.
  • the control part 30 electrically measures the load of the washings Q.
  • FIG. 5A and FIG. 5B are flow charts illustrating outlines of the detections 1 to 4 .
  • step S 1 when the dewatering rotation of the dewatering drum 4 is started by starting the dewatering operation (step S 1 ), as described above, the control part 30 measures the load of the washings Q in the dewatering drum 4 (step S 2 ), and then the motor 6 rotates at a constant speed of 120 rpm (step S 3 ).
  • step S 4 the control part 30 begins to accelerate the motor 6 to 240 rpm (step S 4 ), and the detection 1 described above is implemented during the acceleration of the motor 6 (step S 5 ).
  • step S 5 a result of the detection 1 is not “OK” (step S 5 : No)
  • step S 5 the control part 30 stops the motor 6 , stops the rotation of the dewatering drum 4 (step SS 6 ), and then determines whether the dewatering operation can be restarted or not (step S 7 ).
  • Restart of the dewatering operation refers to rotating the dewatering drum 4 to restart the dewatering operation immediately after the control part 30 stops rotation of the dewatering drum 4 to suspend the dewatering operation. Detailed conditions will be described below. Sometimes, the restart may also be conducted according to the biased degree of the washings Q.
  • the control part 30 executes the restart (step S 8 ).
  • the control part 30 shortens the duration of constant rotation at 120 rpm to be less than the duration of constant rotation at 120 rpm during the dewatering operation just stopped.
  • the washings Q are in a state of being attached to an inner circumferential surface of the dewatering drum 4 to a certain extent and removing most of the water, it is acceptable to shorten the duration of constant rotation at 120 rpm.
  • the duration of the dewatering operation can be shortened. It shall be noted that such reduction of duration can also be executed in subsequent restarts.
  • step S 9 the control part 30 executes an imbalance correction (step S 9 ).
  • the control part 30 opens the water supply valve 13 and supplies water into the dewatering drum 4 to reach a specified water level, and the washings Q in the dewatering drum 4 are immersed in the water so as to be easily scattered.
  • the control part 30 rotates the dewatering drum 4 and the rotary wing 5 , so that the washings Q attached to the inner circumferential surface of the dewatering drum 4 are dropped and stirred, thereby correcting the bias of the washings Q in the dewatering drum 4 .
  • step S 5 determines that the washings Q are not biased through the detection 1 .
  • the control part 30 continues to execute the above detection 2 (step S 10 ) in the acceleration of the motor 6 .
  • step S 10 determines that the washings Q are biased
  • the control part 30 stops the motor 6 and the dewatering drum 4 so as to suspend the dewatering operation (step S 11 ).
  • the control part 30 confirms whether the dewatering condition of the currently suspended dewatering operation is a “wool fabric mode” or “independent dewatering operation” (step S 12 ).
  • the wool fabric mode is a dewatering condition for dewatering the washings Q that are easy to absorb the water such as wool fabrics.
  • the dewatering condition is the wool fabric mode (step S 12 : Yes)
  • the control part 30 executes the restart for shortening the duration of constant rotation at 120 rpm (step S 14 ).
  • the control part 30 may mistakenly determine that the result of the detection 2 is not “OK”. Moreover, when the imbalance correction is performed regardless of the mistaken determination and the wool fabric absorbs a great amount of water again, the mistaken determination may occur again in a subsequent detection 2 . Therefore, in a case where the result of the detection 2 is determines as not “OK” under the wool fabric mode, the restart rather than the imbalance correction is performed (step S 14 ) as long as the restart is not implemented (step S 13 : Yes). On the other hand, in the case of being not before the restart, that is, as long as the currently suspended dewatering operation is already restarted (step S 13 : No), the control part 30 executes the imbalance correction (step S 15 ).
  • the independent dewatering operation refers to the dewatering condition under which the rinsed washings Q are put into the dewatering drum 4 and dewatered rather than the dewatering operation executed subsequently to the washing operation and the rinsing operation.
  • the dewatering condition is the independent dewatering operation (step S 12 : Yes) and before the restart (step S 13 : Yes)
  • the control part 30 executes the restart (step S 14 ).
  • the control part 30 can also prompt a user to redispose the washings Q in the dewatering drum 4 through the display of the operation part 20 and the error report performed by a buzzer.
  • the control part 30 executes the imbalance correction (step S 15 ).
  • the control part 30 determines that the currently suspended dewatering operation is before the restart, and determines whether the dewatering operation can be restarted subsequently or not (step S 16 ).
  • the control part 30 executes the restart for shortening the duration of constant rotation at 120 rpm (step S 17 ).
  • the control part 30 executes the imbalance correction (step S 18 ).
  • step S 10 determines that the washings Q are not biased in the detection 2
  • the control part 30 confirms if the value of the timer 35 is greater than a set value per load (step 19 ). That is, in the step S 19 , the control part 30 confirms whether the duration counted by the timer 35 already reaches a set value corresponding to the load of the washings Q in the dewatering drum 4 .
  • the set value is described in detail below.
  • step S 19 When the value of the timer 35 is greater than the set value per load (step S 19 : Yes), and the motor 6 is in the state of rotating at a constant speed of 240 rpm, the control part 30 executes the above detections 3 and 4 (step S 20 ). In a case where results of the detections 3 and 4 are not “OK” (step S 20 : No), that is, the control part 30 determines that the washings Q are biased, the control part 30 stops the motor 6 and the dewatering drum 4 so as to suspend the dewatering operation (step S 11 ), and executes the corresponding processing in steps S 12 to S 18 .
  • step S 20 in a case where the results of the detection 3 and detection 4 are “OK” (step S 20 : Yes), that is, in a case where the control part 30 determines that the washings Q are not biased in the detection 3 and detection 4 , the control part 30 continues to rotate the motor 6 at a constant speed of 240 rpm so as to continue the dewatering at 240 rpm (step S 21 ).
  • FIG. 6A and FIG. 6B are flow charts illustrating control actions related to the detections 1 detection 2 . Firstly, referring to FIG. 6A and FIG. 6B , the detections 1 and 2 are described. The detections 1 and 2 are detections of the bias of the washings Q by utilizing the rotating speed of the motor 6 .
  • step S 4 the control part 30 begins to accelerate the motor 6 to 240 rpm and begins the detections 1 and 2 .
  • the control part 30 trigger the timer 35 to time, and measures a rotating speed V 0 of the motor 6 at the beginning of the acceleration through the rotating speed reading apparatus 34 (step S 31 ).
  • the rotating speed V 0 is about 120 rpm.
  • the detection time of the detections 1 and 2 i.e. the acceleration time for the motor 6 to accelerate to 240 rpm varies depending on the load. The reason is that the heavier the washings Q are, the more time the motor 6 needs to reach the rotating speed of 240 rpm. Therefore, the set value per load related to the acceleration time of the motor 6 is obtained in advance through experiments and the like, and stored in the memory 32 .
  • control part 30 begins to count through the counter 36 (step S 32 ), and performs the counting once every 0.3 second by initializing the counter 36 once every 0.3 second (step S 33 and step S 34 ).
  • the control part 30 measures the rotating speed Vn (n: count value) of the motor 6 in each counting (step S 35 ). In step S 35 , the control part 30 calculates the difference Sn between the measured rotating speed Vn and the rotating speed Vn ⁇ 1 measured before the Vn. Then, the control part 30 calculates the accumulated value U based on an absolute value of the difference between a difference Sn and a previous difference Sn ⁇ 1 in the step S 35 .
  • control part 30 confirms whether the value of the timer 35 is already greater than the set value per load, that is, whether the measuring time of the timer 35 reaches the set value corresponding to the load of the washings Q in the dewatering drum 4 (step S 36 ).
  • the step S 36 is equivalent to the step S 19 described above (referring to FIG. 5A ).
  • step S 38 determines that whether the difference Sn just calculated falls within the scope of the detection 1 (step S 38 ).
  • the given amount is obtained in advance through the experiment and the like and stored in the memory 32 .
  • FIG. 7 is a graph illustrating the relationship between the rotating speed of the motor 6 and the difference Sn in association with the detection 1 .
  • the horizontal axis indicates the rotating speed (unit: rpm)
  • the longitudinal axis indicates the difference Sn (unit: rpm).
  • step S 38 when the difference Sn is smaller than or equal to the threshold value, the control part 30 determines that the difference Sn falls within the scope of the detection 1 (step S 38 : Yes). In this way, in the detection 1 , the instability degree of the acceleration of the dewatering drum 4 indicating whether the washings Q are biased is detected according to the difference Sn.
  • step S 38 When the control part 30 determines that the difference Sn falls within the scope of the detection 1 (step S 38 : Yes), the rotation of the motor 6 is stopped (step S 6 ), and the corresponding processing in the above steps S 7 to S 9 is executed (referring to FIG. 5A ).
  • the processing of the step S 31 to step 38 is included in the above step S 5 (referring to FIG. 5A ).
  • control part 30 determines whether the accumulated value U just calculated falls within the scope of the detection 2 or not (step S 39 ).
  • step S 37 when the load of the washings Q in the dewatering drum 4 is greater than a given amount (step S 37 : No), the control part 30 executes the determination performed by the detection 2 in the step S 39 rather than the determination performed by the detection 1 in the step S 38 .
  • the control part 30 executes the determination performed by the detection 2 in the step S 39 rather than the determination performed by the detection 1 in the step S 38 .
  • the reason is that in a case where the amount of the washings Q is greater than the given amount, since a great amount of water is oozed out from the washings Q or the bias of the washings Q is sharply changed due to the sudden attachment of the washings Q to the inner circumferential surface of the dewatering drum 4 , it is possible that the detection 1 cannot be performed stably. Therefore, in a case where the amount of the washings Q is greater than the given amount, the detection 1 is omitted.
  • the threshold value is preset for the accumulated value U and stored in the memory 32 .
  • FIG. 8 is a diagram illustrating the relationship between the rotating speed of the motor 6 and the accumulated value U in association with the detection 2 .
  • the horizontal axis indicates the time (unit: sec)
  • the longitudinal axis indicates the accumulated value U (unit: rpm).
  • the threshold value is set as two threshold values, i.e. the upper threshold value represented by cardinal points and the upper threshold value represented by triangular points.
  • the upper threshold value is a value greater than the lower threshold value.
  • the control part 30 determines that the accumulated value U falls within the scope of the detection 2 (step S 39 : Yes). In this way, in the detection 2 , the instability degree of the acceleration of the dewatering drum 4 indicating whether the washings Q are biased is detected according to the accumulated value U.
  • step S 39 When the control part 30 determines that the accumulated value U falls within the scope of the detection 2 (step S 39 : Yes), the rotation of the motor 6 is stopped (step S 11 ), and the corresponding processing in the above steps S 12 to S 18 is executed.
  • the treatment of the steps S 31 to S 37 and the step S 39 is included in the step S 10 described above (referring to FIG. 5A ).
  • step S 16 the control part 30 determines whether the bias of the washings Q is large enough to enable the accumulated value U to be greater than the upper threshold value or whether the currently suspended dewatering operation is already restarted or not.
  • step S 16 In a case where the accumulated value U is greater than the upper threshold value or the dewatering operation is already restarted (step S 16 : Yes), the control part 30 executes the imbalance correction (Step S 18 ). In a case where the accumulated value U is lower than the upper threshold value and the dewatering operation is not restarted (step S 16 : No), the control part 30 executes the restart (step S 17 ).
  • the determination about whether the accumulated value U is greater than the upper threshold value is equivalent to the determination about whether the restart can be carried out in the step S 16 of FIG. 5B , and the determination about whether the restart is already carried out is equivalent to the determination about whether it is before the restart in the step S 16 of FIG. 5B .
  • the control part 30 determines whether the bias within the range of the detection 2 is small enough to perform the restart subsequently or large enough to perform the imbalance correct according to the determination abpit whether the accumulated value U is greater than the upper threshold value, and chooses to execute the restart and the imbalance correction according to the bias.
  • step S 40 the control part 30 acquires the duty ratio of the voltage applied to the motor 6 at the time point when the value of the timer 35 reaches the set value as the reference duty ratio d 0 .
  • the motor 6 is in the acceleration state of accelerating to 240 rpm.
  • the control part 30 determines the timing for acquiring the reference duty ratio d 0 in the step S 40 according to the load measured during the dewatering operation of the dewatering drum 4 . In other words, the control part 30 changes the timing for terminating the detections 1 and 2 and starts the subsequent detections 3 and 4 according to the load. Therefore, the detections 3 and 4 can be executed at the optimum timing corresponding to the amount of the washings Q.
  • FIG. 9A and FIG. 9B are flow charts illustrating control actions related to the detections 3 and 4 .
  • the detections 3 and 4 are described.
  • the detections 3 and 4 are detections of the bias of the washings Q by utilizing the duty ratio of the voltage applied to the motor 6 .
  • step S 40 the control part 30 acquires the reference duty ratio d 0 and starts the detections 3 and 4 .
  • the rotating speed of the motor 6 is in the state of reaching 240 rpm, and the motor 6 rotates at a constant speed of 240 rpm.
  • a first count value E and a second count value T exist and are stored in the memory 32 .
  • the control part 30 respectively resets the first count value E and the second count value T to the initial value 0 (step S 41 ).
  • control part 30 initiates the timer 35 to begin the timing (step S 42 ) and monitors whether the value of the timer 35 is greater than 8.1 seconds.
  • the detections 3 and 4 are executed within this specified period of 8.1 seconds after the reference duty ratio d 0 is acquired.
  • control part 30 starts the counting through the counter 36 in the step S 42 , and performs the counting once every 0.3 second by initializing the timer 36 once every 0.3 second (step S 43 and step S 44 ).
  • step S 44 the control part 30 adds 1 (+1) to the second count value T at the timing when the counter 36 is initialized, i.e. the timing when the counting is performed at every time.
  • the control part 30 acquires a duty ratio do (n: count value) of the voltage applied to the motor 6 during counting at every time of timing (step S 45 ). That is, within this specified period of 8.1 seconds, the control part 30 acquires a duty ratio dn once at the specified timing of every 0.3 second.
  • the control part 30 performs the operation for the corrected duty ratio dn diff at the timing of every 0.3 second on the basis of the following formula (1) and formula (2).
  • the corrected duty ratio dn_diff is a value obtained by correcting the duty ratio dn acquired at the same timing, so that the detection in the detection 4 can be accurately executed.
  • a and B in the formula (1) and formula (2) are constants obtained through the experiment and the like.
  • step S 46 when the acquired duty ratio dn is greater than or equal to the duty ratio dn ⁇ 1 acquired last time (step S 46 : Yes), the control pat 30 adds 1 (+1) to the first count value E (step S 47 ). Furthermore, in the detection 3 , the duty ratio dn originally acquired by the control part 30 is the above reference duty ratio d 0 . In another aspect, when the acquired duty ratio dn is less than the duty ratio dn ⁇ 1 acquired at the last timing (step S 46 : No), the control part 30 resets the first count value E to the initial value 0 (zero) (step S 48 ).
  • control part 30 confirms whether the value of the timer 35 is less than 8.1 seconds, i.e., whether the measuring time of the timer 35 is greater than 8.1 seconds (step S 49 ).
  • step S 49 when the load of the washings Q in the dewatering drum 4 is greater than a given amount (step S 50 : Yes), the control part 30 determines whether the latest first count value E falls within the scope of the detection 3 (step S 51 ).
  • the given amount is obtained in advance through the experiment and the like and stored in the memory 32 .
  • the threshold is preset for the first count value E and stored in the memory 32 .
  • FIG. 10 is a graph illustrating the relationship between the time and the first count value E in association with the detection 3 .
  • the horizontal axis indicates the time (unit: sec)
  • the longitudinal axis indicates the first count value E.
  • the threshold is provided with two values, i.e. a lower threshold value represented by a single-point line and an upper threshold value represented by a double-point line. Both the upper value and the lower value are unrelated to the elapsed time and are fixed values. The upper value is greater than the lower value.
  • the motor 6 can also rotate at a constant speed of 240 rpm, so that the duty ratio dn is gradually decreased.
  • the first count value E is stabilized in proximity to the initial value 0.
  • the duty ratio dn is not decreased.
  • the first count value E is increased rather than returned to the initial value, and as shown by the dotted line, the first count value E is greater than the lower threshold value at any timing.
  • the first count value E may also be greater than the upper threshold value.
  • step S 51 when the latest first count value E is greater than or equal to the lower threshold value, the control part 30 determines that the first count value E falls within the scope of the detection 3 (step S 51 : Yes). That is, when the first count value E within the above specified period of 8.1 seconds is greater than or equal to the specified threshold, the control part 30 determines that the washings Q in the dewatering drum 4 are biased.
  • the accurate detection for controlling the change of the duty ratio dn during the detection in real time can also be performed.
  • the accuracy for detecting whether the washings Q are biased can be improved.
  • step S 51 determines whether the corrected duty ratio dn_diffjust obtained falls within the scope of the detection 4 .
  • step S 50 when the load of the washings Q in the dewatering drum 4 is less than a given amount (step S 50 : No), the control part 30 executes the determination performed by the detection 4 in the step S 52 rather than the determination performed by the detection 3 in the step S 51 .
  • the detection 3 when the detection 3 is executed in a case where the amount of the washings Q is less than the given amount, the first count value E is instable since the duty ratio dn is converged at an early stage, so it is possible that the detection 3 cannot be executed stably. Therefore, in a case where the amount of the washings Q is less than the given amount, the detection 3 is omitted.
  • FIG. 11 is a graph illustrating a relationship between the time and the corrected duty ratio dn_diff in association with the detection 4 .
  • the horizontal axis represents time (unit: second) and the vertical axis represents the corrected duty ratio dn_diff.
  • two threshold values including a lower threshold value represented by a single-dot dash line and an upper threshold value represented by a double-dot dash line are set for the threshold.
  • the upper threshold value and the lower threshold value gradually increase with elapsed time, respectively.
  • the upper threshold value is greater than the lower threshold value.
  • the corrected duty ratio dn_diff is smaller than the lower threshold value and gradually decreases as shown by a solid line.
  • the corrected duty ratio dn_diff does not decrease, but exceeds the lower threshold value as shown by a dotted line.
  • the corrected duty ratio dn_diff may exceed the upper threshold value. Therefore, returning to FIG. 9A , when the corrected duty ratio dn_diff is greater than the lower threshold value, the control part 30 determines that the corrected duty ratio dn_diff falls within the scope of the detection 4 (step S 52 : Yes).
  • the corrected duty ratio dn_diff obtained by the above formulas (1) and (2) is a value set when the duty ratio dn is equal to or greater than the reference duty ratio d 0 and is increased over time. Therefore, the corrected duty ratio dn_diff does not fall within the threshold values only when the duty ratio dn decreases normally relative to the reference duty ratio d 0 .
  • the first count value E for the detection 3 and the corrected duty ratio dn_diff for the detection 4 refer to indexes of change between the duty ratio dn of the voltage applied to the motor 6 and the reference duty ratio d 0 within the specified period of 8.1 seconds for maintaining the rotating speed of 240 rpm.
  • the control part 30 determines whether the washings Q in the dewatering drum 4 are biased based on such indexes in the detections 3 and 4 .
  • the control part 30 measures the load of the washings Q in the dewatering drum 4 (step S 2 in FIG. 5A ) when the dewatering drum 4 starts to rotate, and determines the timing for acquiring the reference duty ratio d 0 according to the measured load (step S 36 in FIG. 6A ).
  • step S 51 determines that the first count value E falls within the scope of the detection 3 (step S 51 : Yes) or determines that the corrected duty ratio dn_diff falls within the scope of the detection 4 (step S 52 : Yes)
  • step S 11 determines that the corrected duty ratio dn_diff falls within the scope of the detection 4
  • step S 52 determines that the corrected duty ratio dn_diff falls within the scope of the detection 4
  • step S 52 determines that the corrected duty ratio dn_diff falls within the scope of the detection 4
  • step S 52 determines that the corrected duty ratio dn_diff falls within the scope of the detection 4
  • step S 52 determines that the corrected duty ratio dn_diff falls within the scope of the detection 4
  • Steps S 16 A and S 16 B in FIG. 9B are included in the above step S 16 (referring to FIG. 5B ). Specifically, the determination in the step S 16 A is equivalent to the determination of whether it is before the restart in the step S 16 in FIG. 5B ; and the determination in the step S 16 B is equivalent to the determination of whether the restart is performed in the step S 16 in FIG. 5B .
  • step S 12 determines whether the dewatering condition is neither a woolen fabric mode nor a single-dewatering operation.
  • the control part 30 determines whether the currently suspended dewatering operation is before a restart in the step S 16 A.
  • the control part 30 determines whether the bias of the washings Q is as low as an extent that both the first count value E and the corrected duty ratio dn_diff are smaller than respective upper threshold values.
  • step S 16 A: Yes When the currently suspended dewatering operation is before the restart (step S 16 A: Yes) and the first count value E and the corrected duty ratio dn_diff are smaller than the respective upper threshold values (step S 16 B: Yes), the control part 30 executes the restart (step S 17 ).
  • step S 16 A: No When the currently suspended dewatering operation is not before the restart, i.e., the restart is completed (step S 16 A: No), the control part 30 executes imbalance correction (step S 18 ). In addition, even if the currently suspended dewatering operation is before the restart (step S 16 A: Yes), in a case where at least one of the first count value E and the corrected duty ratio dn_diff is greater than the respective upper threshold value (step S 16 B: No), the control part 30 executes imbalance correction (step S 18 ).
  • the controller 30 determines the bias falling within the scopes of the detection 3 and the detection 4 is small enough to continue to restart or is large enough to require imbalance correction according to the first count value E and the corrected duty ratio dn_diff in steps S 16 B to S 18 .
  • the control part 30 executes the restart or the imbalance correction according to the first count value E and the corrected duty ratio dn_diff, i.e., according to whether the values are greater than or equal to the respective upper threshold values. Therefore, when the washings Q are determined to be biased, the imbalance correction is not necessarily executed. Thus, when the first count value E and the corrected duty ratio dn_diff are values representing small bias of the washings Q, the time for the dewatering operation can be shortened by executing the restart immediately.
  • step S 49 the control part 30 terminates the detections 3 and 4 (step S 53 ).
  • FIG. 12 is a flow chart illustrating outlines of the detection 5 - 1 and the detection 5 - 2 .
  • whether the washings Q are biased is detected by utilizing the duty ratio.
  • the motor 6 continues to rotate at the constant speed of 240 rpm for a specified duration. With expiration of the specified time, the control part 30 accelerates the motor 6 from 240 rpm to the target rotating speed of 800 rpm (step S 60 ).
  • the control part 30 takes the duty ratio of the voltage applied to the motor 6 at the time point as an ⁇ value (step S 61 ).
  • 300 rpm is the rotating speed at which the dewatering drum 4 does not store water and is least affected by the eccentricity of the dewatering drum 4 . Therefore, the ⁇ value at 300 rpm is the duty ratio in a state of being least affected by the eccentricity of the dewatering drum 4 and only affected by the load of the washings Q.
  • step S 62 the control part 30 performs the above detection 5 - 1 when the motor 6 continues to accelerate and the rotating speed is increased from 600 rpm to 729 rpm.
  • step S 62 the control part 30 determines that the washings Q are biased
  • step S 63 the control part 30 stops the motor 6 and stops the rotation of the dewatering drum 4 (step S 63 ). In this way, after the dewatering operation is suspended, the control part 30 determines whether the dewatering operation is before the restart, i.e., determines whether the currently suspended dewatering operation has already been restarted (step S 64 ).
  • step S 64 When the dewatering operation is before the restart (step S 64 : Yes), the control part 30 executes the restart (step S 65 ). When the dewatering operation is not before the restart (step S 64 : No), the control part 30 executes the imbalance correction (step S 66 ).
  • step S 62 determines that the washings Q are not biased in the detection 5 - 1
  • the control part 30 continues to perform the detection 5 - 2 in a state that the motor 6 continues accelerating from 730 rpm (step S 67 ).
  • step S 67 Yes
  • the control part 30 determines that the washings Q are not biased in the detection 5 - 2
  • the control part 30 continues dewatering the washings Q by rotating the motor 6 at the constant target rotating speed after accelerating the motor 6 to the target rotating speed (800 rpm) (step S 68 ).
  • step S 67 when the result of the detection 5 - 2 is not “OK” (step S 67 : No), i.e., in a case where the control part 30 determines that the washings Q are biased, the control part 30 continues to dewater the washings Q by rotating the motor 6 at a constant rotating speed below the target rotating speed (step S 69 ).
  • FIG. 13 is a flow chart illustrating control actions related to the detection 5 - 1 .
  • control part 30 starts the detection 5 - 1 as the rotating speed of the motor 6 reaches 600 rpm in a state of continuing accelerating the motor 6 after the step S 61 (referring to FIG. 12 ) (step S 70 ).
  • control part 30 starts to count through the counter 36 (step S 71 ).
  • the counter 36 is initialized once every 0.3 second so as to count once every 0.3 second (steps S 72 and S 73 ).
  • the control part 30 acquires a rotating speed of the motor 6 during each counting and a duty ratio dn (n: a count value) of voltage applied to the motor 6 during the counting (step S 74 ). Namely, the control part 30 acquires the rotating speed and the duty ratio dn of the motor 6 at each specified moment within a period where the rotating speed of the motor 6 reaches 800 rpm from 240 rpm.
  • control part 30 calculates a correction value Bn obtained by correcting the duty ratio dn with the a value according to a following formula (3) in step S 74 .
  • X and Y in the formula (3) are constants derived from experiments and the like. Different from simple ratio calculation, a weight in the formula (3) is changed, so that the correction value Bn obtained by correcting the duty ratio dn can execute the detection 5 - 1 with good accuracy.
  • control part 30 calculates a moving accumulated value Cn (n: count value) of the correction value Bn in step S 74 .
  • the moving accumulated value Cn (n: count value) is a sum of 5 consecutive correction values Bn in a counting sequence.
  • the 4 correction values Bn on the rear side of the 5 correction values Bn forming the moving accumulated value Cn ⁇ 1 are same with the 4 correction values Bn on the front side of the 5 correction values Bn forming the moving accumulated value Cn. It shall be noted that the quantity of the correction values Bn summed for forming the moving accumulated value Cn is not limited to 5.
  • control part 30 calculates a threshold of the moving accumulated value Cn (step S 75 ) according to a following formula (4).
  • the threshold (rotating speed) ⁇ a+b Formula (4)
  • the a and b in the formula (4) are constants derived from experiments and the like and stored in the memory 32 .
  • constants a and b vary depending on the current rotating speed of the motor 6 and a selected dewatering condition.
  • the threshold herein has multiple values at the same rotating speed. It shall be noted that, it can be known from the formula (4) that the threshold is not influenced by the a value.
  • control part 30 confirms whether the current rotating speed of the motor 6 is less than 730 rpm or not (step S 76 ).
  • step S 76 the control part 30 determines whether a last moving accumulated value Cn falls within the scope of the detection 5 - 1 or not (step S 77 ).
  • FIG. 14 is a graph illustrating a relationship between the rotating speed and the moving accumulated value Cn in association with the detections 5 - 1 and 5 - 2 .
  • a horizontal axis represents the rotating speed (unit: rpm)
  • a longitudinal axis represents the moving accumulated value Cn.
  • two threshold values including a first threshold value represented by a single-dot dash line and a second threshold value represented by a double-dot dashed line are set according to, for example, different dewatering conditions. The first threshold value is higher than the second threshold value.
  • dewatering conditions a dewatering condition in which dewatering operation is carried out after water is stored in the dewatering drum 4 and washings are rinsed in “ordinary rinsing” mode, a dewatering condition of “water-splashing and dewatering” in which dewatering is performed and water is splashed to the washings Q when water is drained, a dewatering condition of “restart”, etc.
  • the use operates the operation part 20 to make a selection from these dewatering conditions, and selection is received by the control part 30 .
  • the acceleration of the motor 6 needs a force since the washings Q contain a great quantity of water; while under the condition of “water-splashing and dewatering” and “restart”, the acceleration of the motor 6 may need a very tiny force since the washings are in a state of removing water to some extent.
  • the control part 30 uses the first threshold value higher than the second threshold value since the detection can hardly be implemented using the second threshold value.
  • the control part 30 uses the second threshold value lower than the first threshold value since the detection is not accurate if the control part 30 uses the first threshold value.
  • the control part 30 uses the first threshold value higher than the second threshold value since the detection can hardly be implemented using the second threshold value in the detection 5 - 1 .
  • the control part 30 uses the second threshold value lower than the first threshold value since the detection is not accurate if the control part 30 uses the first threshold value in the detection 5 - 1 .
  • the detection 5 - 1 is executed by using the threshold value adapted with different loads of the washings Q respectively.
  • threshold values including the first threshold value and the second threshold value are illustrated in FIG. 14 , more than 3 threshold values may also be set according to various dewatering conditions and loads.
  • the moving accumulated value Cn at each rotating speed is increased under the condition that the washings Q are biased due to large eccentricity (referring to the dotted lines in FIG. 14 ). If the washings Q are greatly biased, the moving accumulated value Cn is larger than the set threshold values, i.e., a corresponding one of the first threshold value and the second threshold value.
  • control part 30 determines that the moving accumulated value Cn falls within the scope of the detection 5 - 1 (step S 77 : “Yes”).
  • step S 77 When the control part 30 determines that the moving accumulated value Cn falls within the scope of the detection 5 - 1 (step S 77 : “Yes”), the rotation of the motor 6 is stopped (the above step S 63 ) and the corresponding processing in step S 64 -step S 66 is executed.
  • the processing in step S 71 -step S 77 is included in the step S 62 (referring to FIG. 12 ).
  • step S 76 the control part 30 ends the detection 5 - 1 , and then starts the detection 5 - 2 (step S 78 ).
  • FIG. 15 is a flow chart illustrating control actions related to detection 5 - 2 .
  • control part 30 starts to carry out the detection 5 - 2 (step S 78 above) as the rotating speed of the motor 6 reaches 730 rpm.
  • control part 30 starts to count through the counter 36 (step S 79 ) and initializes the counter 36 per 0.3 s so as to carry out counting per 0.3 s (step S 80 and step S 81 ).
  • control part 30 may acquire the rotating speed of the motor 6 during each counting and the duty ratio dn of the voltage applied to the motor 6 during the counting, and calculate the correction value Bn and the moving accumulated value Cn (step S 82 ).
  • the control part 30 calculates the threshold for the moving accumulated value Cn according to the formula (4) (step S 83 ).
  • the constants a and b forming the formula (4) are same as those in detection 5 - 1 , and may have different values due to the current rotating speed of the motor 6 and the selected dewatering condition.
  • the threshold herein includes multiple values at the same rotating speed, e.g., the first threshold value and the second threshold value.
  • control part 30 confirms whether the current rotating speed of the motor 6 reaches the target rotating speed (800 rpm) (step S 84 ).
  • step S 84 determines whether the newest moving accumulated value Cn falls within the scope of the detection 5 - 2 (step S 85 ).
  • the moving accumulated value Cn at each rotating speed is increased.
  • the moving accumulated value Cn is larger than the set threshold value, i.e., a corresponding one of the first threshold values and the second threshold values.
  • control part 30 determines that the moving accumulated value Cn falls within the scope of the detection 5 - 2 (step S 85 : “Yes”).
  • step S 85 the rotating speed L of the motor 6 is acquired at a determined time point, i.e., in the detection 5 - 2 (step S 86 ).
  • control part 30 rotates the motor 6 constantly at the acquired rotating speed L, strictly speaking, a rotating speed obtained by rounding away the single digit of the rotating speed L from zero, so that the washings Q are continuously dewatered (step S 69 above).
  • the control part 30 prolongs dewatering time at the rotating speed L so as to obtain a same dewatering effect as that of dewatering at an original target rotating speed.
  • step S 84 the control part 30 terminates the detection 5 - 2 and rotates the motor 6 constantly at the target rotating speed so as to continue dewatering the washings Q (step S 68 above).
  • the control part 30 changes the threshold according to the dewatering conditions received by the operation part 20 (steps S 75 and S 83 ). Moreover, when the acquired duty ratio dn, strictly, the moving accumulated value Cn calculated based on the acquired duty ratio dn is greater than a changed specified threshold value, the control part 30 determines whether the washings Q are biased in the dewatering drum 4 . In other words, since whether the washings Q are biased can be detected using the threshold suitable for each dewatering condition during the dewatering operation in each dewatering condition, the accuracy for detecting whether the washings Q are biased can be improved.
  • control part 30 can control the detection of the foam in the drainage pipeline 14 in parallel with the related control in the detections 1 to 5 .
  • FIG. 16 is a flow chart illustrating a control action of detecting the foam in the dewatering operation.
  • the control part 30 starts the dewatering of the dewatering drum 4 by starting the dewatering operation (the step S 1 ).
  • the rotating speed of the motor 6 is increased as described above (referring to FIG. 3 ).
  • the control part 30 acquires the rotating speed of the motor 6 once at every specified timing in the dewatering operation and the duty ratio of the voltage applied to the motor 6 , i.e., the duty ratio of applied voltage (step S 91 ).
  • the control part 30 calculates a voltage limit value V_limit (step S 93 ).
  • the voltage limit value V_limit is the duty ratio of the maximum voltage applied to the motor 6 at each rotating speed and is calculated by substituting the rotating speed into the specified formula.
  • control part 30 detects the foam in the drainage pipeline 14 by determining whether the duty ratio of the applied voltage acquired in the step S 91 is greater than the voltage limit value V_limit at every timing (step S 94 ).
  • step S 95 When the control part 30 determines that the foam blocks the drainage pipeline 14 (step S 94 : Yes), whether it is before the restart is determined, i.e., whether the currently suspended dewatering operation is restarted (step S 95 ).
  • step S 95 When it is before the restart (step S 95 : Yes), the control part 30 executes the restart (step S 96 ). When it is not before the restart (step S 95 : No), the control part 30 executes the imbalance correction (step S 97 ). Regardless of executing the restart or the imbalance correction, the dewatering operation may be restarted after a temporary suspension. Therefore, during the restart of the dewatering operation, the foam in the drainage pipeline 14 may disappear naturally.
  • step S 92 when the rotating speed of the motor 6 is greater than 600 rpm (step S 92 : No), the control part 30 terminates the processing of detecting the foam (step S 98 ).
  • control of FIG. 16 not only is used for detecting the foam, but also can be used for detecting a phenomenon of “stagnant water” that the water in the outer drum 3 cannot reach the drainage pipeline 14 due to vibration and the like.
  • the detections 1 to 4 are executed in order to electrically detect whether the washings Q in the dewatering drum 4 are biased.
  • the detection 6 described below can also be executed instead of the detections 1 to 4 , or the detection 6 can also be executed in parallel with the detections 1 to 4 .
  • FIG. 17 is a time chart illustrating a state of the rotating speed of the motor 6 during the dewatering operation in association with the detection 6 , and specifically, a chart from which a portion equivalent to the low-speed eccentricity detection section in FIG. 3 is deleted. Therefore, in the time chart of FIG. 17 , the horizontal axis represents the elapsed time and the vertical axis represents the rotating speed (unit: rpm) of the motor 6 , as in FIG. 3 . It shall be noted that, in FIG. 17 , the state of the duty ratio of the voltage applied to the motor 6 by the control part 30 is represented by the dotted line, besides the state of the rotating speed of the motor 6 is represented by the solid line.
  • the control part 30 controls the duty ratio in such a manner that the maximum value of the duty ratio is generated during an acceleration state of accelerating the motor 6 from 120 rpm to 240 rpm in the low-speed eccentricity detection section. At this time, an accelerated speed of the motor 6 is controlled to be always fixed.
  • the maximum value of the duty ratio generated during the acceleration state of the motor 6 is called the maximum duty ratio dmax below.
  • the control part 30 controls the duty ratio in such a manner that the maximum duty ratio dmax is generated at a rotating speed (for example, 180 rpm) slightly lower than the rotating speed (200 rpm to 220 rpm) at which the dewatering drum 4 resonates, and specifically, longitudinally resonates.
  • Such control of the duty ratio can be executed commonly regardless of the magnitude of the load of the washings Q in the dewatering drum 4 .
  • a gain and the like representing the difference between the target rotating speed of the motor 6 and a current actual rotating speed and representing responsiveness of the change of the rotating speed relative to the duty ratio are preset in the control part 30 .
  • the rotating speed at which the longitudinal resonance occurs is called longitudinal resonance rotating speed below.
  • the control part 30 starts to accelerate the motor 6 from 120 rpm, the duty ratio gradually increases as shown by the dotted line in FIG. 17 . Then, the maximum duty ratio dmax is generated when the rotating speed of the motor 6 reaches 180 rpm.
  • the washings Q are not biased in the dewatering drum 4 , since the motor 6 can be accelerated to 240 rpm even if the duty ratio is relatively small after the maximum duty ratio dmax is generated, the duty ratio gradually decreases as shown by the dotted line.
  • the washings Q are biased in the dewatering drum 4 , the vibration is increased as the rotating speed of the motor 6 approaches the longitudinal resonance rotating speed. Therefore, since the duty ratio must be increased to 240 rpm, the duty ratio dmax needs to be increased even after the maximum duty ratio dmax is generated, and the duty ratio after the maximum duty ratio dmax is generated can hardly decrease. Therefore, after the maximum duty ratio dmax is generated, the duty ratio may be maintained at a value slightly lower than the maximum duty ratio dmax without decrease as shown by a one-dot lock line in FIG. 17 , or may be increased after temporarily falling below the maximum duty ratio dmax as shown by the double-dot dash line in FIG. 17 . In the detection 6 , whether the washings Q in the dewatering drum 4 are biased is electrically detected by monitoring a relative change between the duty ratio after the maximum duty ratio dmax is generated and the maximum duty ratio dmax.
  • FIG. 18 is a flow chart illustrating control actions related to the detection 6 . Referring to FIG. 8 , the detection 6 is described.
  • step S 4 the control part 30 starts to accelerate the motor 6 from 120 rpm to 240 rpm. Then, since the duty ratio has the maximum value when the rotating speed of the motor 6 reaches, for example, 180 rpm in the acceleration state of accelerating the motor 6 to 240 rpm, the control part 30 takes the maximum value as the maximum duty ratio dmax (step S 101 ).
  • a count value G and an accumulated value H exist and are stored in the memory 32 .
  • the control part 30 resets the count value G and the accumulated value H to an initial value 0 (step S 101 ).
  • step S 102 when the rotating speed of the motor 6 reaches the rotating speed (for example, 200 rpm) immediately before the longitudinal resonance (step S 102 : Yes), the control part 30 starts the timer 35 to start the timing and starts to count by the counter 36 (step S 103 ). As a result, the detection 6 is started.
  • the control part 30 initializes the counter 36 once every specified time (for example, 0.1 second) to count once every 0.1 second (steps S 104 and S 105 ) by referring to the value of the timer 35 .
  • the control part 30 adds one (+1) to the count value G once at timing of initializing the counter 36 every time in step S 105 , i.e., at timing of counting every time.
  • the control part 30 acquires the duty ratio dg (g: count value G) of the voltage applied to the motor 6 once during counting when counting every time (step S 106 ). In other words, the control part 30 acquires the duty ratio dg once every specified time of 0.1 second.
  • step S 106 the control part 30 acquires the duty ratio dg once every specified time and calculates an accumulated value H of a difference between the duty ratio dg and the previous maximum duty ratio dmax.
  • the difference is a value obtained by subtracting the duty ratio dg from the maximum duty ratio dmax.
  • the accumulated value H is a value obtained by adding the latest difference to the last accumulated value H, and is updated every time when adding 1 to the count value G.
  • FIG. 19 is a graph illustrating the relationship between the count value G and the accumulated value H in association with the detection 6 .
  • the horizontal axis represents the count value G
  • the vertical axis represents the accumulated value H.
  • a specified threshold is set for the accumulated value H.
  • the threshold is obtained from the following formula (5) using the count value G added with 1 every specified time and the maximum duty ratio dmax as variables.
  • Threshold ( K ⁇ G ⁇ L ) ⁇ M ⁇ ( N ⁇ dmax) Formula (5)
  • K, L, M and N in the formula (5) are constants previously obtained from experiments and the like, and are stored in the memory 32 .
  • the threshold is changed in a manner of increasing as the count value G increases.
  • the threshold can be pre-stored in the memory 32 , and can also be calculated by the control part 30 based on the formula (5) every time when the count value G is changed.
  • step S 107 when the count value G reaches the timing of, for example, 20, and specifically, reaches the timing of start of longitudinal resonance (step S 107 : Yes), the control part 30 confirms whether the latest accumulated value H is smaller than the specified threshold value obtained from the formula (5) (step S 108 ).
  • step S 108 Yes
  • the control part 30 determines whether the washings Q are biased in the dewatering drum 4 and stops the motor 6 (step S 109 ). Therefore, the rotation of the dewatering drum 4 is stopped.
  • the processing of steps S 11 to S 18 can also be executed (referring to FIG. 5B ).
  • step S 108 When the accumulated value H is no less than the specified threshold (step S 108 : No) and the count value G reaches the specified value (for example, 81 ) (step S 110 : Yes), the rotating speed of the motor 6 reaches 240 rpm and the motor 6 is in a state of rotating at the constant speed of 240 rpm. In this case, the control part 30 terminates the detection 6 (step S 111 ).
  • the accuracy for detecting whether the washings Q are biased can be improved by monitoring the detection 6 for the index representing the relative change between the duty ratio dg after the maximum duty ratio dmax is generated and the maximum duty ratio dmax, i.e., the accumulated value H.
  • the duty ratio is set in such a manner that the maximum duty ratio dmax is generated at a rotating speed slightly lower than the longitudinal resonance rotating speed.
  • the longitudinal resonance occurs at an earlier timing after the maximum duty ratio dmax is generated.
  • the phenomenon that the accumulated value H can hardly increase occurs earlier. Therefore, that the washings Q are biased in the dewatering drum 4 can be detected early and correctly.
  • the maximum duty ratio dmax is generated at the longitudinal resonance rotating speed, a bad condition that the subsequent change of the rotating speed becomes unstable may appear.
  • such a bad condition can be suppressed by generating the maximum duty ratio dmax at the rotating speed slightly lower than the longitudinal resonance rotating speed.
  • FIG. 20 is a graph illustrating the relationship between the count value G and the duty ratio in association with the detection 6 .
  • the horizontal axis represents the count value G and the vertical axis represents the duty ratio.
  • the maximum duty ratio dmax is increased accordingly.
  • the load is relatively large, as shown by the solid line, a relatively large duty ratio is required to increase the rotating speed of the motor 6 at a constant acceleration, and the maximum duty ratio dmax is increased accordingly.
  • the load is relatively small, as shown by the dotted line, a relatively small duty ratio is required to increase the rotating speed of the motor 6 at the constant accelerated speed, and the maximum duty ratio dmax s decreased accordingly.
  • a difference R when the load is relatively small is apparently smaller than a difference S when the load is relatively large. So, compared with the case of a large load, it is conceivable that it is more difficult for the accumulated value H in the case of a small to increase, and the accumulated value H is also smaller than the threshold even if the washings Q are not biased. In this way, when the load is relatively small, the dewatering operation may be stopped due to false detection of presence of the bias of the washings Q.
  • the threshold is obtained from the formula (5) using the count value G and the maximum duty ratio dmax as the variables, as described above. Since the maximum duty ratio dmax varies depending on the magnitude of the load of the washings Q in the dewatering drum 4 , the threshold is determined differently based on the load. Therefore, since whether the washings Q are biased is detected based on an optimal threshold corresponding to the magnitude of the load of the washings Q in the dewatering drum 4 in the detection 6 , the false detection can be prevented even if the load is relatively small. Thus, the accuracy for detecting whether the washings Q are biased can be further improved.
  • the motor 6 is controlled through the duty ratio on a premise that the motor 6 is a variable frequency motor.
  • the motor 6 is controlled through the voltage applied to the motor 6 instead of the duty ratio.
  • the rotating speed in the above description has specific values, such as 120 rpm, 240 rpm or 800 rpm, these specific values are values that vary according to performance of the dewatering machine 1 .
  • the duty ratio may be obtained for making various determinations in the above description.
  • the duty ratio can be original data of the obtained duty ratio, can also be a corrected value that is corrected as needed, and can further be a value calculated based on the duty ratio like the moving accumulated value Cn.
  • the dewatering drum 4 of above embodiments can be configured vertically in a manner of rotating by using an axis 16 extending in the up-down direction X as a center.
  • the dewatering drum 4 can also be configured obliquely in a manner of obliquely extending the axis 16 relative to the up-down direction X.

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  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Control Of Washing Machine And Dryer (AREA)
  • Accessory Of Washing/Drying Machine, Commercial Washing/Drying Machine, Other Washing/Drying Machine (AREA)
US15/576,592 2014-06-30 2016-05-26 Dewatering Machine Abandoned US20180155862A1 (en)

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KR102477491B1 (ko) 2021-04-28 2022-12-15 일쌍산업영농조합법인 곡물 탈수장치

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KR102005360B1 (ko) 2019-07-30
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KR20180012807A (ko) 2018-02-06
CN107709650B (zh) 2019-10-01
WO2016000433A1 (zh) 2016-01-07

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