EP2659045A2

EP2659045A2 - Washing machine wherein the unbalanced load is balanced

Info

Publication number: EP2659045A2
Application number: EP11794110.4A
Authority: EP
Inventors: Ahmet Yorukoglu; Hayri Kerem ERENAY; Onur Yaman
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2010-12-27
Filing date: 2011-12-06
Publication date: 2013-11-06
Also published as: WO2012089444A2; CN103270208B; WO2012089444A3; CN103270208A

Abstract

The present invention relates to a washing machine (1) comprising a drum (2) rotated around the horizontal axis and wherein the laundry is placed, a tub (3) wherein the drum (2) moves, a motor (4) providing the drum (2) to be driven, a pulley (5) disposed outside the tub (3), transmitting the movement of the motor (4) to the drum (2) and rotating together with the drum (2), more than one baffle (6) disposed on the cylindrical inner surface of the drum (2), providing the laundry to be tumbled and serving to balance by the water being transferred therein in unbalanced load condition occurred in the spin-drying process, at least one discharge conduit (7) providing the water received into the baffles (6) during the balancing process to be discharged into the tub (3) at the end of the spin-drying process after performing the balancing function and a control unit (8) that detects the unbalanced load in the drum (2) during the spin-drying process wherein the drum (2) is rotated at high speed by means of the acceleration, vibration or load sensors.

Description

WASHING MACHINE WHEREIN THE UNBALANCED LOAD IS BALANCED

The present invention relates to a washing machine wherein the unbalanced load inside the drum is balanced by using water.
In washing machines having drums rotating around the horizontal axis, the washing process is performed by rotating the drum at different speeds in different steps of the washing program. While the drum is being rotated, an uneven load distribution occurs as a result of the laundry piling up at some areas. Especially in the spin-drying step wherein the drum is rotated at high speed, the unbalanced load resulting from the laundry and structural factors increases vibration and noise and causes the washing machine to wear out. Furthermore, the spin-drying performance of the washing machine is adversely affected.
In the state of the art, various solutions have been developed for balancing the unbalanced load. Fixing balancing weights produced from heavy materials such as concrete or metal onto the tub of the washing machine is a commonly used method. Water is used to realize the balancing operation in some embodiments since the balancing weights make the transportation of the washing machine difficult. Water is filled into the balancing chambers formed on the tub or the drum, particularly to the drum baffles, in order to balance the detected unbalanced load, and discharged when the unbalanced load is eliminated. Using water to balance the unbalanced load also creates some other problems. In the washing machine, in the spin-drying process wherein the drum is rotated at high speed, water is filled into the balancing chambers or the drum baffles that serve like balancing chambers. The spin-drying process is performed in several steps and when spin-drying process is paused, the position of unbalanced load also changes since the distribution of laundry in the drum is generally changed and the water filled in the balancing chambers should be discharged for performing an effective balancing in the next spin-drying step. If the water used for balancing is not discharged, an effective balancing cannot be performed in the spin-drying steps after the first spin-drying step, the water remaining in the balancing chambers results in increase of the vibration level and hence noisy operation. The water that cannot be discharged from the balancing chambers and the water remaining when washing process is not performed, furthermore cause increase in residue and bacteria, hence creating problems in terms of hygiene.
In the state of the art United States Patent Application No. US2004083774, a washing machine is explained wherein the unbalanced load is balanced by means of the liquid holding boxes. The liquid filled in the liquid holding boxes is discharged by decreasing the rotational speed of the drum.
In the state of the art European Patent Application No. EP2025797, a washing machine is explained wherein unbalanced load is balanced by means of the balance tanks.
The aim of the present invention is the realization of a washing machine wherein the unbalanced load in the drum is balanced effectively by performing spin-drying in successive periods.
The washing machine realized in order to attain the aim of the present invention, explicated in the first claim and the dependent claims thereof, comprises a pulley that transmits the movement of the motor to the drum, which rotates together with the drum, at least one baffle that serves as balancing chamber by transferring water therein for balancing the unbalanced load formed during the spin-drying step and a position sensor composed of a transmitter disposed on the pulley and a receiver disposed in the tub, providing to angularly determine the positions thereof according to the highest position the baffle reaches during the rotational movement of the drum, and the control unit that detects the unbalanced load, determines the angular positions of the baffles, wherein water is filled by means of the position sensor during the balancing process, brings the drum baffles to the highest position successively at the end of the spin-drying process and provides the water in the baffles to be entirely discharged by keeping them at this position.
In an embodiment of the present invention, the control unit calculates the angular position of the baffles by processing the signals received from the position sensor and from the speed measuring unit that measures the rotation number of the motor.
In another embodiment of the present invention, the control unit provides the baffle, wherein water discharge process is performed, to be kept at the highest position and the discharge pump discharging water from the baffle to be operated as long as the calculated waiting time period in accordance with the durations regulated depending on the discharge times calculated with respect to the amounts of water transferred into the baffle during balancing and recorded in its memory.
In another embodiment of the present invention, the pulley that rotates the drum has radial arms in numbers equal to the number of baffles on the drum, the arms are aligned with the drum baffles and the position sensor transmitter is connected on at least one of the arms.
In another embodiment of the present invention, position sensor transmitters that generate signals at different voltage values are connected on the arms of the pulley.
In another embodiment of the present invention, the position sensor, the transmitter of which is a magnet and the receiver of which is a Hall sensor, is used for determining angular positions of the baffles.
In yet another embodiment of the present invention, the position sensor, the transmitter of which is a light source and the receiver of which is an optical sensor, is used for determining angular positions of the baffles.
In the washing machine of the present invention, the water filled into the baffles during the spin-drying process is provided to be entirely discharged at the end of the spin-drying period, the baffles are made ready for a new balancing process in the next spin-drying period, and increase in vibration and noise are prevented by performing an effective balancing in each successive spin-drying period.
The washing machine realized in order to attain the aim of the present invention is illustrated in the attached figures, where:
Figure 1 - is the sideways schematic view of a washing machine.
Figure 2 - is the perspective view of a washing machine tub.
Figure 3 - is the rear schematic view of a washing machine.
The elements illustrated in the figures are numbered as follows:

Washing machine
Drum
Tub
Motor
Pulley
Baffle
Discharge conduit
Control unit
Transmitter
Receiver
Position sensor
Speed measuring unit
Arm
Discharge pump

The washing machine (1) comprises a drum (2) rotated around the horizontal axis and wherein the laundry is placed, a tub (3) wherein the drum (2) moves, a motor (4) providing the drum (2) to be driven, a pulley (5) disposed outside the tub (3), transmitting the movement of the motor (4) to the drum (2) and rotating together with the drum (2), more than one baffle (6) disposed on the cylindrical inner surface of the drum (2), providing the laundry to be tumbled and serving to balance by water being transferred therein in unbalanced load condition formed in the spin-drying process, at least one discharge conduit (7) providing the water received in the baffles (6) during the balancing process into the tub (3) to be discharged at the end of the spin-drying process after performing the balancing function and a control unit (8) that detects the unbalanced load in the drum (2) during the spin-drying process wherein the drum (2) is rotated at high speed by means of the acceleration, vibration or load sensors (not shown in the figures).
The washing machine (1) of the present invention comprises,
- a position sensor (11) having at least one receiver (10), disposed on the rear wall of the tub (3) and remaining immovable together with the tub (3), the position of which is determined by taking the highest position the baffle (6) reaches during the rotational movement of the drum (2) as the reference point (R) and at least one transmitter (9) disposed on the pulley (5) and rotating together with the pulley (5), providing the angular positions of the baffles (6) with respect to the reference point (R) to be determined and
- the control unit (8) that provides the motor (4) to bring the water filled baffles (6) to the reference point (R) successively by rotating the drum (2) intermittently according to the baffle (6) position angles detected by the position sensor (11) after the drum (2) stops rotating due to inertia effect at the end of the spin-drying process, and provides the drum (2) to be stopped by braking the motor (4) at the moment each baffle (6) reaches the reference point (R) which is the highest position thereof and the water in the baffle (6) to be discharged from the discharge conduit (7).
In the washing machine (1), during the spin-drying process performed after the washing period, the unbalanced load is detected by means of the sensors that detect amount and position of the unbalanced load and the balancing operation is performed by filling the baffles (6) opposite the unbalanced load with water. After the drum (2) stops at the end of the spin-drying process, at least one more spin-drying period is performed. The water filled into the baffles (6) has to be discharged at the end of each spin-drying process. At the end of the spin-drying periods, by rotating the drum (2) as much as the angles suitable to the angular positions of the baffles (6) detected by the position sensor (11), and by successively bringing the baffles (6) to the highest position, in other words to the reference point (R), the motor (4) is braked, the drum (2) is paused for a certain time and the water in the baffle (6) at the uppermost position is provided to be entirely discharged. Thus, the baffles (6) are made ready to perform balancing for the next spin-drying process.
The position sensor (11) provides the angular position of the baffles (6) to be detected by means of the transmitter (9) fastened to the movable pulley (5) and the receiver (10) fastened to the immovable tub (3). When the drum (2) rotates, the pulley (5) that transmits motion to the drum (2) and the transmitter (9) fastened to the pulley (5) also rotate. Signal is generated by the position sensor (11) when the transmitter (9) passes in front of the receiver (10) during rotation and the control unit (8) detects the angular position of the baffles (6) according to signals received from the position sensor (11).
In the washing machine (1), in order to discharge the water in the baffles (6) at the end of the spin-drying process, the angular distance of the baffles (6) with respect to the reference point (R) is determined by the position sensor (11) and the control unit (8), when the drum (2) stops rotating due to inertia effect. Afterwards, the control unit (8) operates the motor (4) for a short while, providing the drum (2) to be rotated as much as the angle that the first baffle (6), the water in which will be discharged, has moved away from the reference point (R) and the baffle (6) to be brought to the reference point (R). Afterwards, the control unit (8) operates the motor (4) intermittently, the other water filled baffles (6) are brought to the reference point (R) successively and the water therein is discharged.
In an embodiment of the present invention, the washing machine (1) comprises a speed measuring unit (12) that measures the rpm of the motor (4) and transmits this information to the control unit (8), for example a tachogenerator, and the control unit (8) that determines the angular position of the baffles (6) with respect to the reference point (R) by processing the signals received from the position sensor (11) and the speed measuring unit (12). Signal is sent by the position sensor (11) at the moment the baffle (6) passes from the reference point (R), and the speed measuring unit (12) counts the rpm of the motor (4) after the baffle (6) passes the reference point (R) and provides the angular position of the baffle (6) to be determined by the control unit (8).
In another embodiment of the present invention, the control unit (8) provides the baffle (6), that undergoes water discharge process, to be kept waiting at the reference point (R) which is the highest position, according to the water amount – discharge time table regulated as per the discharge times calculated with respect to the amounts of water transferred into the baffle (6) during balancing and recorded in its memory. For example, if 200 ml of water is filled into the baffle (6) during the balancing process, the baffle (6) is kept waiting for 10 seconds at the highest position, if filled with 600 ml of water, the baffle (6) is kept waiting for 30 seconds at the highest position. Thus, the baffles (6) are kept waiting at the highest position for the time duration determined with respect to the amount of water therein, the baffle (6) is not kept waiting if there isn’t any water therein, thereby preventing unnecessary pauses in between the spin-drying periods.
In another embodiment of the present invention, the washing machine (1) comprises a discharge pump (14) disposed in the discharge conduit (7), that is operated by the control unit (8) in the balancing process for as long as the time period determined with respect to amount of water received into the baffle (6), thus providing the water in the baffle (6) to be discharged.
In another embodiment of the present invention, the pulley (5) has more than one arm (13), extending in the radial direction between the hub and the outer rim connected to the center of the drum (2), in numbers equal to the number of baffles (6) in the drum (2) and showing the position of the baffles (6) by being positioned in alignment with the baffles (6), and to at least one of which the position sensor (11) transmitter (9) is fastened.
In yet another embodiment of the present invention, the control unit (8) is provided to easily determine the angular positions of the baffles (6) aligned with the arms (13) by fastening transmitters (9) that generate signals in a different voltage value to each arm (13) of the pulley (5).
In another embodiment of the present invention, the transmitter (9) of the position sensor (11) is a magnet and the receiver (10) is a Hall sensor.
In another embodiment of the present invention, the transmitter (9) of the position sensor (11) is a light source and the receiver (10) is an optical sensor.
In the washing machine (1) of the present invention wherein the drum (2) baffles (6) are used as balancing chambers, the water filled into the baffles (6) in proportion with the amount of unbalanced load occurred during the spin-drying process is provided to be completely discharged at the end of the spin-drying period, the baffles (6) are made ready to the next spin-drying period for a new balancing process, increases of vibration and noise are prevented by performing an effective balancing in every successive spin-drying period and the problems like accumulation of residue and growth of bacteria in the water remaining in the baffles (6) are avoided.
It is to be understood that the present invention is not limited by the embodiments disclosed above and a person skilled in the art can easily introduce different embodiments. These should be considered within the scope of the protection disclosed by the claims of the present invention.

Claims

- A washing machine (1) comprising a drum (2) wherein the laundry is placed, a tub (3) wherein the drum (2) moves, a motor (4) providing the drum (2) to be driven, a pulley (5) disposed outside the tub (3), transmitting the movement of the motor (4) to the drum (2) and rotating together with the drum (2), more than one baffle (6) disposed on the drum (2), serving to balance by transferring water therein in unbalanced load condition, at least one discharge conduit (7) providing the water received into the baffles (6) to be discharged into the tub (3) at the end of the spin-drying process and a control unit (8) that detects the unbalanced load,

characterized in that

- a position sensor (11) having at least one receiver (10), disposed on the tub (3), the position of which is determined by taking the highest position the baffle (6) reaches during the rotational movement of the drum (2) as the reference point (R) and at least one transmitter (9) disposed on the pulley (5), providing the angular positions of the baffles (6) with respect to the reference point (R) to be determined and

- the control unit (8) that provides the motor (4) to bring the baffles (6) to the reference point (R) successively by rotating the drum (2) intermittently according to the baffle (6) position angles detected by the position sensor (11) at the end of the spin-drying process, and provides the drum (2) to be stopped by braking the motor (4) at the moment each baffle (6) reaches the reference point (R) and the water in the baffle (6) to be discharged from the discharge conduit (7).
A washing machine (1) as in Claim 1, characterized in that a speed measuring unit (12) that measures the rpm of the motor (4) and transmits this information to the control unit (8), and the control unit (8) that determines the angular position of the baffles (6) with respect to the reference point (R) by processing the signals received from the position sensor (11) and the speed measuring unit (12).
A washing machine (1) as in Claim 1 or 2, characterized in that the control unit (8) which provides the baffle (6) that undergoes water discharge process, to be kept waiting at the reference point (R), according to the water amount – discharge time table regulated depending on the discharge times calculated with respect to the amounts of water transferred into the baffle (6) during balancing and recorded in its memory.
A washing machine (1) as in any one of the above Claims, characterized in that a discharge pump (14) disposed in the discharge conduit (7), that operates for as long as the time period determined by the control unit (8) with respect to the amount of water received into the baffle (6) in the balancing process, thus providing the water in the baffle (6) to be discharged.
A washing machine (1) as in any one of the above Claims, characterized in that the pulley (5) having more than one arm (13), in numbers equal to the number of baffles (6) in the drum (2) and positioned in alignment with the baffles (6), and to at least one of which the transmitter (9) is fastened.
A washing machine (1) as in Claim 5, characterized in that the pulley (5) wherein the transmitters (9) that generate signals in different voltage values are fastened to each arm (13).
A washing machine (1) as in any one of the above Claims, characterized in that the position sensor (11), the transmitter (9) of which is a magnet and the receiver (10) of which is a Hall sensor.
A washing machine (1) as in any one of the Claims 1 to 6, characterized in that the position sensor (11), the transmitter (9) of which is a light source and the receiver (10) of which is an optical sensor.