Classifications

• • 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
  • D06F2103/00—Parameters monitored or detected for the control of domestic laundry washing machines, washer-dryers or laundry dryers
  • D06F2103/24—Spin speed; Drum movements
• • 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
  • D06F2105/52—Changing sequence of operational steps; Carrying out additional operational steps; Modifying operational steps, e.g. by extending duration of steps
• • 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 
  • D06F33/48—Preventing or reducing imbalance or noise

Definitions

• the present invention refeis to an improved method for controlling, in an automatic clothes washing machine, the off-balance condition m which the washload may be set whenever the lotational speed of the drum of the machine is changed in view of carrying out a spin-extraction phase or cycle.
• Working programmes of household-type clothes washing machines are generally known to traditionally comprise mainly a washing phase, in which the washload-holdmg dium is d ⁇ ven to rotate at a low speed (preferably in an alternately dnection reveismg mode), a spin-extraction run-up oi washload distribution phase, in which the rotating speed of the dium is gradually increased up to an intermediate value and, finally, an actual spm-exti action phase, in which the rotating speed of the drum is increased to a maximum value.
• the washload contained m the lotatmg drum tends to get distributed in an irregular manner, ie. unevenly in the same drum, thereby bringing about unbalance moments that are the cause of mechanical stresses.
• a correct distribution of the washload in the drum is particularly important during the spin-extraction lun-up phase, which is usually carried out at rotating speeds of the drum comprised between approx. 50 and 90 rpm, since it is actually this phase that conditions m a decisive mannei also the subsequent high-speed spm-exti action phase
• Such sti esses can damage the washing assembly of the machine and, anyway, jeopaidize the stability of the same machine, they are a source of noise and aie mdesn ably ti ansmitted to the flooi
• Anothei diawback of the pnoi-ait solutions lies in the fact that the operation of each contiol system is closely con elated to the technical and dimensional characteristics of the washing machine, so that the system itself must be reset and leiated each time that it is applied foi use in washing machines that have differing charactenstics
• the clothes washing machine can be noticed to be of a tiaditional type foi household oi lesidential applications compiismg mamly a dium 4 adapted to hold the washload and be lotatably d ⁇ ven by an electric motoi 5, the lattei being foi instance of the asynchi onous single-phase type
• the motoi 5 also dnves a tachometiic geneiatoi 6, oi similar speed measmmg device, which m turn dnves a piogiammable contiol device 7 with a signal that is indicative of the instant i otatmg speed of the motoi 5 and, theiefoie, the drum 4
• the contiol device 7 piefeiably comp ⁇ ses a cropiocessoi , which may foi instance be of the Motoi ola 68HC1 1 type, and has a contiol output 9 that is adapted to dnve a powei stage 8 foi supplying the motoi 5 in a vanable-speed mode
• the powei stage 8 is piefeiably of the type compiismg at least a Tiiac, adapted to be conti oiled in a phase-conti ol mode to co espondmgly vary the I otatmg speed of the motoi 5 and the dium 4
• the control device 7 can be easily pi ogi ammed accoi ding to specific needs to automatically control the l otatmg spee ⁇ el the motoi 5
• the output 9 of the device 7 controls the powei stage 8 and theiefoie the motoi 5 with an eiroi signal that vanes according to both the pie-set piogiamme and the signal being leceived fiom the tachomet ⁇ c geneiatoi 6, which is indicative of the instant speed of the dium 4
• the contiol device 7 is theiefoie capable of easily measmmg also the instant off-balance state B of the dium 4
• the contiol device 7 can be noticed to be geneially piogiammed foi cairymg out at least a woi g oi opeiational cycle compiismg following mam phases in a sequence
• washing and/oi linsmg phase tO - tl in which, in a geneially pei se known mannei , the clothes in the dium 4 is soaked with watei (or wash liquoi) and the dium itself is dnven to lotate lepeatedly (and piefei bly in alternately opposite dnections) duimg penods T, wheiem the dium 4 lotates at a low speed VO that is piefeiably of appiox 55 m duimg this phase
• a conect balancing of the drum 4 during the spm-exti action lun-up phase tl - t2 (which in practice is a phase of initial spm-exti action at an mtei mediate speed) is critical m view of a good operation of the clothes washing machine duimg the actual spin-extraction phase t2 - 13
• the spm-exti action lun-up phase tl - 12 is now descnbed m greatei detail with lefeience to also Figuie 3, m which the continuous-line curve and the dashed-lme one lepiesent the vanations vs time of the instant speed and the lated speed of the dium 4, lespectively It should be noticed that the teim "rated speed" is used heie to mean the speed commanded by the contiol device 7 in accoi dance with the pie-set pi ogi amme selected
• the contiol device 7 is set so as to be able to detect the afoie mentioned instant off-balance state B of the dium 4 sequentially (eg at pi e-detei mined fixed intervals of appiox 160 msec)
• the stage 8 is dnven so as to accelei ate the i otatmg dium 4 thiough a speed increment I, which may foi instance be of appiox 2 ipm
• the stage 8 is dnven so as to decelerate the dium 4 by a soeed deciement D Piefeiably, although not solely, the speed mciements I and the speed deciements D aie the same, le equal to each othei , and substantially constant m lesponse to each detection of said off-balance condition B
• the I otatmg speed of the dium 4 is giadually mci eased up to said mtei mediate value VI only if and when the dium itself is detected to be sufficiently balanced
• the piactical lesult is that, when the spm-exti action lun-up phase leaches its conclusion at the instant t2 and the actual spm-exti action phase t2 - 13 is theiefore due to begin , the I otatmg dium 4 is certainly m an optimally balanced state
• the off-balance state B of the dium 4 is smallei than the pi e-detei mined thieshold value, so that the lated speed of the same dium is mci eased by an mciement I in lesponse to each one of the afoi e mentioned detections
• the off-balance condition B is on the contiaiy detected to be gi eatei than said pi e-detei mined thieshold value, so that the above cited l ated speed of the dium is deci eased by a deciement D m lesponse to each one of said detections
• the giaduality and the peiiodicity of speed mciements and deciements duimg the spm-exti action n-up phase enable this same phase to be earned thiough m advantageously short penods of time, without any need foi the same phase to be lestarted fiom an initial condition Furtheimoie the l apidity with which optimum conditions of balanced state of the dium aie leached ensuies an impioved oveiall stability of the washing machine, with coiiespondmg technical advantages
• the method accoidmg to the present invention is capable of being implemented m different machines without any need ansmg foi appiop ate lesettmgs or lei atmgs to be earned out
• Fuitheimoie the method accoidmg to the piesent nvention can be easily rmplemented in any traditional type of automatic washing machines (pieferably provrded wrth on electronic control system) without any need aiismg foi them to undeigo paiticulai spactuial modifications It will anyway be appieciated that the washing machine can also make use of different means to detect the off-balance state of the drum such as foi instance electiomechanical devices of any suitable kind
• the above descnbed method can be the subject of a numbei of modifications without depaitmg fi om the scope of the pi esent invention
• the sequential detection of the off-balance state B can be carried out at variable intervals, instead of fixed ones, and/oi it is the pie-determined off-balance threshold that may be vanable
• sard off-balance thieshold can be substantially decreasing with the increase of the speed of the dium 4

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Control Of Washing Machine And Dryer (AREA)
• Detergent Compositions (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=11395439

Family Applications (1)

Country Status (2)

Cited By (20)

Citations (6)

• 1998
  • 1998-11-10 IT IT1998PN000081A patent/IT1305553B1/it active
• 1999
  • 1999-10-23 WO PCT/EP1999/008041 patent/WO2000028128A1/en active Application Filing

Patent Citations (6)

Also Published As

Similar Documents

Legal Events