Patent Application
20080034809
These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, of which:
Reference will now be made in detail to the embodiment of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiment is described below to explain the present invention by referring to the figures.
Referring to
The water tub 11 is mounted at a predetermined angle α to an installation surface of the washing machine such that a front part 11a of the water tub 11, in which an inlet 11b is formed, is higher than a rear part 11c of the water tub 11. The rotary drum 12, which is mounted in the water tub 11, is mounted in the same way as the water tub 11 such that a front part 12a of the rotary drum 12, in which an inlet 12b is formed, is higher than a rear part 12c of the rotary drum 12.
Specifically, a rotation axis A of the rotary drum 12 is at the predetermined angle α to the installation surface of the washing machine such that the front part 12a of the rotary drum 12, in which the inlet 12b is formed, is directed to the upper front. The rotary drum 12 has a rotary shaft 13 coupled to the center of the rear part 12c thereof. The rotary shaft 13 is rotatably supported at the rear center of the water tub 11. Consequently, the rotary drum 12 is rotatably mounted in the water tub 11.
The reason why the rotation axis A of the rotary drum 12 is at the predetermined angle α to the installation surface of the washing machine is to gather a predetermined amount of water for washing and rinsing in the rotary drum 12, when water is supplied into the rotary drum 12, such that laundry is wetted by the gathered water. At this time, the water is supplied into the rotary drum 12 up to the height of holes 12d. In order that an appropriate amount of water is gathered in the rotary drum 12 and washing is smoothly performed, the inclination angle α of the rotary drum 12 may be approximately 15 degrees.
In the front part 12a of the rotary drum 12 are also formed a plurality of holes 12d. At the inner surface of the rotary drum 12 are mounted a plurality of lifters 14 to lift and drop the laundry in the rotary drum 12 when the rotary drum 12 is rotated. The reason why the circumferential surface of the rotary drum 12 is at a predetermined angle β to the rotation axis A of the rotary drum 12 is to guide water flowing to the radial direction of the rotary drum 12 such that the water can flow to the holes 12d of the front part 12a along the inclined inner surface of the rotary drum 12 due to a centrifugal force, and then the water can be discharged out of the rotary drum 12, as shown in
At the outside of the rear part 11c of the water tub 11 is mounted a motor 15 to rotate the rotary shaft 13 connected to the rotary drum 12 such that washing, rinsing, and spin-drying operations are performed. The motor 15 includes a stator 15a fixed to the rear part 11c of the water tub 11, a rotor 15b rotatably mounted at the outer circumference of the stator 15a, and a rotary disc 15c to connect the rotor 15b and the rotary shaft 13.
In the inner lower part of the water tub 11 is mounted a washing heater 16 to heat wash water supplied into the water tub 11. To this end, the water tub 11 is provided at the lower part there of with a heater receiving part 17, which protrudes downward such that the washing heater 16 is received in the heater receiving part 17, and, at the same time, a predetermined amount of wash water is gathered in the heater receiving part 17. Specifically, the heater receiving part 17 is constructed such that the washing heater 16 is submerged in the wash water gathered in the heater receiving part 17. Since the wash heater 16 is received in the heater receiving part 17, the rotary drum 12 can be rotated without interference with the washing heater 16.
In the front part of the machine body 10 is formed an inlet 18b, which corresponds to the inlet 12b of the rotary drum 12 and the inlet 11b of the water tub 11 such that laundry can be put into or removed from the rotary drum through the inlets. At the front part of the machine body 10 is mounted a door 18 to open and close the inlet 18b. Between the inlet 10b of the machine body 10 and the inlet 11b of the water tub 11 is mounted a cylindrical diaphragm 11d to prevent leakage of wash water.
Above the water tub is mounted a detergent supply unit 19 to supply detergent and a water supply unit 20 to supply water (wash water or rinse water).
The detergent supply unit 19 is partitioned into a plurality of sections. The detergent supply unit 19 is mounted in the front part of the machine body such that a user can easily put detergent and rinse into the respective sections. The partitioned sections include a preliminary wash detergent box to store detergent for preliminary washing, a main wash detergent box to store detergent for main washing, and a rinse box to store rinse for rinsing. This construction is disclosed in Korean Patent Application No. 2003-0011317. The partitioned sections may be constructed according to a generally known art.
The water supply unit 20 includes a first water supply pipe 22 connected between an external water supply pipe 21 to supply water (wash water or rinse water) into the water tub 11 and the detergent supply unit 19, a second water supply pipe 23 connected between the detergent supply unit 19 and the water tub 11, and a water supply valve 24 mounted on the first water supply pipe 22 to control the supply of water. This construction allows water to pass through the detergent supply unit 19 before the water is supplied into the water tub 11 such that the detergent stored in the detergent supply unit 19 can be supplied into the water tub 11.
The washing machine according to the present invention further includes a drainage unit 30 to drain water from the water tub 11 and a circulation unit 40 to supply the water heated by the washing heater 16 in the water tub 11 into the rotary drum 12. The drainage unit 30 includes a first drainage pipe 31 connected to a drainage port 17a formed at the heater receiving part 17 of the water tub 11 to guide the water in the water tub 11 to the outside, a drainage pump 32 mounted on the drainage pipe 31, and a drainage pipe 33 connected to the outlet side of the drainage pump 32. The circulation unit 40 includes a flow changing valve 41 mounted on the drainage pipe 33 connected to the outlet side of the drainage pump 32, a circulation pipe 42 extending from the flow changing valve 41 to the inlet 12b side of the rotary drum 12, and an injection nozzle 43 mounted at the outlet of the circulation pipe 42. The flow changing valve 41 serves to change of the flow of water such that the water from the outlet of the drainage pump 32 is drained to the outside or flows to the circulation pipe 42 side. The flow changing valve 41 may be a normal electric-powered three-way valve. The injection nozzle 43 is mounted adjacent to the inlet 12b of the rotary drum 12 to inject water into the rotary drum 12 through the inlet 12b of the rotary drum 12.
According to this construction, as shown in
The signal input unit 50 inputs operation information, such as a washing course, washing temperature, water-discharging RPM, and addition of rinsing, which is selected by a user, to the control unit 56. The water level detection unit 52 detects the water level of water supplied into the water tub 11, and the temperature detection unit 54 detects the temperature of water supplied into the water tub 11.
The control unit 56 is a microcomputer to control the washing machine based on the operation information inputted from the signal input unit 50. The control unit 56 stores motor RPM, motor operation rate (motor on-off time) and the number of water resupplies N (the number of times to resupply water to the minimum water level necessary for heating washing when water is absorbed into the laundry, and therefore, the water level is lowered) set according to the amount of load (the amount or weight of laundry) in the selected washing course.
Consequently, the control unit 56 controls the driving of the motor 15, the water supply unit 20, and the circulation unit 40 such that, when water (wash water or rinse water) is supplied, an appropriate amount of water can be supplied according to the amount of load.
The drive unit 58 drives the motor 15, the washing heater 16, the water supply valve 24, the drainage pump 32, and the flow changing valve 41 according to a driving control signal of the control unit 56.
Hereinafter, a water level control method of the washing machine with the above-stated construction will be described in detail.
The water level control method of the washing machine with the holeless rotary drum 12 according to the present invention is performed to supply an appropriate amount of water based on the amount of laundry by only changing an algorithm while using a water level sensor adopted in a conventional washing machine with a rotary drum having holes.
When a user puts laundry into the rotary drum 12 and selects operation information, such as a washing course, washing temperature, water-discharging RPM, and addition of rinsing, according to kinds of laundry, the operation information selected by the user is inputted to the control unit 56 through the signal input unit 54.
Consequently, the control unit 56 performs a washing operation according to the operation information inputted from the signal input unit 54. First, the control unit 56 determines whether power is on (S100).
When the power is on, the control unit 56 detects the amount of load (the amount or weight of the laundry) put into the rotary drum 12 (S102), and sets motor RPM, motor operation rate (motor on-off time) and the number of water resupplies N (the number of times to resupply water to the minimum water level necessary for heating washing when water is absorbed into the laundry, and therefore, the water level is lowered) according to the detected amount of the load (S104).
Here, the number of water resupplies N is set to restrict the resupply of water based on the amount of the laundry, thereby reducing unnecessary use of water.
Subsequently, the control unit 56 controls the water supply unit 20 to supply water to the laundry. As a result, the water supply valve 24 is opened, and wash water is supplied into the water tub 11 through the water supply pipes 21 and 22, the detergent supply unit 19, and the second water supply pipe 23 (S106).
When water for washing or rinsing is supplied, the water level of the water supplied into the water tub 11 is detected by the water level detection unit 52 to determine whether the detected water level is a predetermined first water level (the minimum amount of water supplied up to a height at which water supplied into the water tub can flow into the rotary drum, i.e., as shown in
When the water level of water is the first water level, water is continuously supplied into the water tub 11 until the water level of water reaches the first water level, and, when the water level of water is not the first water level, the control unit 56 turns the water supply valve 24 off to stop the supply of water (S110).
After the supply of water is stopped, the control unit 56 drives the motor 15 to operate the rotary drum 12 at a predetermined first RPM (approximately 30 RPM) and a predetermined operation rate such that laundry can be wetted by the water supplied into the water tub 11 (S112).
As the rotary drum 12 is rotated, the water is introduced from the water tub 11 into the rotary drum 12. As a result, the water level of the wash water in the water tub 11 is lowered.
Subsequently, the control unit 56 drives the circulation unit 40 to supply an appropriate amount of water (wash water or rinse water) based on the amount of load (the amount of laundry). As a result, the flow changing valve 41 of the circulation unit 41 is operated such that the outlet side of the drainage pump 32 communicates with the circulation pipe 42. Then the drainage pump 32 is operated, and therefore, the water received in the lower part of the water tub 11 is supplied into the rotary drum 12 through the drainage pipe 31 and the circulation pipe 42 (S114). At this time, the water supplied into the rotary drum 12 is injected toward the laundry through the injection nozzle 43 such that the laundry can be wetted by the water. At this time, the rotary drum 12 is rotated at low speed by the motor 15.
In order to check how much water has been absorbed into the laundry, the control unit 56 detects the water level of the water gathered in the water tub 11 after the rotary drum 12 is operated at a predetermined second RPM (approximately 200 RPM) for a predetermined period of time (approximately 1 minute) to discharge the remaining water, which has not been absorbed into the laundry, out of the water tub 11 through the holes 12d formed in the front part 12a of the rotary drum 12 (S116).
During the water-discharging operation, the second RPM of the rotary drum 12 is decided based on the amount of load. The second RPM may be equal to or greater than the first RPM.
Also, the control unit 56 determines whether the water level of the water gathered in the water tub 11 is above a predetermined second water level (the minimum water level for heating washing at which the washing heater is submerged) (S118). When the water level of the water gathered in the water tub 11 is not above the second water level, the control unit 56 determines whether the water resupply operation to replenish the water tub 11 with water has been repeated for the predetermined number of water resupplies N (S120).
When it is determined at S120 that the water resupply operation to replenish the water tub 11 with water has not been repeated for the predetermined number of water resupplies N, the water supply valve 20 is operated to replenish the water tub 11 with water such that the water is resupplied into the water tub 11 until the water level in the water tub 11 reaches the second water level (S122). The procedure is returned to S114 so as to supply an appropriate amount of water (wash water or rinse water) based on the amount of the laundry, and the operation is carried out from S114 until the predetermined number of water resupplies N is repeated.
When it is determined at S118 that the water level of water gathered in the water tub 11 is above the second water level, which means that an appropriate amount of water has been supplied based on the amount of the laundry, the control unit 56 performs a washing operation set according to the amount of load while the water received in the lower part of the water tub 11 is supplied into the rotary drum 12 through the circulation unit 40 (S130). After that, the control unit 56 performs predetermined rinsing and spin-drying operations (S132).
As apparent from the above description, the washing machine with the holeless rotary drum according to the present invention can supply an appropriate amount of water based on the amount of laundry while using a water level sensor adopted in a conventional washing machine with a rotary drum having holes. Consequently, it is possible to control the water level with the optimum amount of water, and therefore, the unnecessary consumption of water is effectively prevented.
Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2006-76821 | Aug 2006 | KR | national |
