Drawer-type washing machine and process of washing laundry using the same

• US 6,618,887 B2
• Filed: 07/02/2001
• Issued: 09/16/2003
• Est. Priority Date: 10/12/2000
• Status: Expired due to Term

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Choi, Byung Keol, Park, Young Hwan, Kim, Hyoun Jin, Kim, Dong Won, Kim, Yong Chul, Jeon, Si Moon
• Primary Examiner(s): Stinson, Frankie L.
• Application Number:
  US09/895,083
• Publication Number:
  US 20020042957A1
• Time in Patent Office: 806 Days
• Field of Search: 68/13.R, 68/231, 68/3.R, 68/26, 68/27, 312/228, 815/8, 815/9
• US Class Current: 8/158
• CPC Class Codes: D06F 2103/18 Washing liquid level
• CPC Class Codes: D06F 2103/30 Pressure
• CPC Class Codes: D06F 2103/68 Operation mode; Program phase
• CPC Class Codes: D06F 2105/00 Systems or parameters controlled or affected by the control systems of washing machines, washer-dryers or laundry dryers
• CPC Class Codes: D06F 2105/02 Water supply
• CPC Class Codes: D06F 2105/28 Electric heating
• CPC Class Codes: D06F 23/04 and rotating or oscillating about a vertical axis
• CPC Class Codes: D06F 33/38 of rinsing
• CPC Class Codes: D06F 33/47 Responding to irregular working conditions, e.g. malfunctioning of pumps safety arrangements D06F37/42
• CPC Class Codes: D06F 37/24 in machines with a receptacle rotating or oscillating about a vertical axis
• CPC Class Codes: D06F 37/40 for driving the receptacle and an agitator or impeller, e.g. alternatively D06F37/304, D06F37/308 take precedence
• CPC Class Codes: D06F 39/12 Casings; Tubs
• CPC Class Codes: D06F 39/125 Supporting arrangements for the casing, e.g. rollers or legs

Abstract

A drawer-type washing machine and process of washing laundry using the washing machine is disclosed. The washing machine has a housing opened at its front to form a cavity. A cabinet, opened at its top, is received in the cavity of the housing such that the cabinet is movable forward or backward relative to the housing. A washing tub unit, consisting of an outer tub and an inner tub, is set within the cabinet. This washing tub unit contains washing water therein, and carries out both a washing operation and a spin-drying operation for laundry contained therein. A drive unit is installed at a position under the outer tub of the washing tub unit, and rotates the inner tub of the washing tub unit. A suspension unit supports the washing tub unit within the cabinet while performing a damping function of attenuating operational vibrations of the washing tub unit. A sliding unit is provided at a movable junction of the housing and the cabinet for allowing a linear sliding movement of the cabinet relative to the housing. In the washing machine, the cabinet is designed to be drawn forward and pushed backward, thus allowing a user to easily put laundry into or take laundry out of the washing tub unit. The washing machine of this invention is also easily installed on a desired area without being critically limited by the vertical space above the top of the washing machine.

Claims

1. A drawer-type washing machine, comprising:

a housing opened at its front to form a cavity;

a cabinet opened at its top and received in the cavity of said housing such that the cabinet is movable forward or backward relative to the housing;

a washing tub unit consisting of an outer tub and an inner tub, and set within the cabinet, said washing tub unit containing washing water therein, and carrying out both a washing operation and a spin-drying operation for laundry contained therein;

a drive unit installed at a position under the outer tub of said washing tub unit, and rotating the inner tub of the washing tub unit;

a suspension unit used for supporting the washing tub unit within said cabinet while performing a damping function of attenuating operational vibrations of the washing tub unit; and

a sliding unit provided at a movable junction of the housing and the cabinet for allowing a linear sliding movement of the cabinet relative to the housing.

2. The drawer-type washing machine according to claim 1, wherein said washing tub unit is covered with an openable cover its top opening.

3. The drawer-type washing machine according to claim 1, wherein a support plate is externally mounted to a bottom wall of said outer tub, with the drive unit being mounted to a lower surface of said support plate, and the suspension unit being provided between said support plate and a bottom wall of said housing.

4. The drawer-type washing machine according to claim 3, wherein said drive unit comprises:

a stator mounted to the lower surface of said support plate, with a coil wound around the stator;

a rotor arranged around said stator;

a rotor core holding said rotor; and

a drive shaft fitted into and fixed to a center of said rotor core at its lower end, and rotatably passing through both the support plate and the outer tub prior to being mounted to the inner tub at its upper end.

5. The drawer-type washing machine according to claim 3, wherein said suspension unit includes a damper positioned between the support plate and the bottom wall of said cabinet, and supporting the washing tub unit within said cabinet while allowing a displacement of the washing tub unit within a predetermined range.

6. The drawer-type washing machine according to claim 5, wherein said damper is opened at its center, and is inclined upward at its upper surface to meet an upward and outward inclined surface of said support plate, and is flat at its lower surface, said damper being positioned on the bottom wall of the cabinet such that the damper is movable relative to the bottom wall of the cabinet within a predetermined range.

7. The drawer-type washing machine according to claim 3, wherein said suspension unit includes a plurality of elastic suspension members positioned between the support plate and the bottom wall of the cabinet, said elastic suspension members supporting the washing tub unit within the cabinet while absorbing vibrations of the washing tub unit and allowing the washing tub unit to elastically restore its upright position when the washing tub unit is inclined relative to a vertical axis of the cabinet.

8. The drawer-type washing machine according to claim 7, wherein each of said elastic suspension members is a coil spring seated on an inclined surface formed at an edge of said support plate and an inclined surface formed on the bottom wall of said cabinet at its opposite ends.

9. The drawer-type washing machine according to claim 8, wherein each of said coil spring is seated on a first spring seat of the support plate at its upper end, and is seated on a second spring seat of the bottom wall of said cabinet at its lower end.

10. The drawer-type washing machine according to claim 1, wherein said sliding unit comprises:

two guide rails extending from the front to the back along opposite side edges of the cabinet'"'"'s bottom wall; and

a plurality of rollers rotatably mounted to lower portions of interior surfaces of opposite sidewalls of said housing, and rotatably supporting said rails thereon, thus allowing the cabinet to be movable forward or backward relative to the housing.

11. The drawer-type washing machine according to claim 1, wherein said drive unit comprises:

a motor housing mounted to a lower surface of the support plate;

a stator mounted to an inner surface of a sidewall of said motor housing, with a coil wound around said stator;

a rotor arranged inside said stator while being regularly spaced apart from an inside edge of said stator;

a rotor core holding said rotor; and

a drive shaft fitted into and fixed to said rotor core, said drive shaft also rotatably penetrating the bottom wall of the motor housing at its lower end, and rotatably penetrating the support plate and the outer tub at its middle portion, and mounted to the bottom wall of said inner tub at its upper end.

12. The drawer-type washing machine according to claim 11, wherein said suspension unit includes a damper, opened at its center and inclined at its upper surface to meet an edge of the bottom wall of said motor housing, said damper being laid on the bottom wall of said cabinet to support the washing tub unit while allowing a displacement of the washing tub unit within a predetermined range.

13. The drawer-type washing machine according to claim 11, wherein said suspension unit includes a plurality of elastic suspension members positioned between the lower surface of said support plate and the bottom wall of said cabinet, said elastic suspension members supporting the washing tub unit within the cabinet while absorbing vibrations of the washing tub unit and allowing the washing tub unit to elastically restore its upright position when the washing tub unit is inclined relative to a vertical axis of the cabinet.

14. The drawer-type washing machine according to claim 1, wherein the interior of said housing is partitioned into two or more cavities by at least one partition wall, with two or more cabinets each having a washing tub unit therein and respectively received in the two or more cavities of said housing.

15. The drawer-type washing machine according to claim 14, wherein the interior of said housing is partitioned into upper and lower cavities by a horizontal partition wall, thus receiving upper and lower cabinets in the upper and lower cavities respectively.

16. The drawer-type washing machine according to claim 15, further comprising:

a first water feeding pipe used for feeding water to an upper washing tub unit received in the upper cabinet;

a first water draining pipe used for draining water from said upper washing tub unit;

a second water feeding pipe used for feeding water to a lower washing tub unit received in the lower cabinet;

a second water draining pipe used for draining water from said lower washing tub unit;

a first connection hose connecting the second water draining pipe to the first water feeding pipe;

a second connection hose connecting the first water draining pipe to the second water feeding pipe;

a first flow control device for selectively draining processed water from a rinsing operation of the upper washing tub unit to the atmosphere through the first water draining pipe or feeding the processed water from the upper washing tub unit to the lower washing tub unit through the second connection hose; and

a second flow control device for selectively draining processed water from a rinsing operation of the lower washing tub unit to the atmosphere through the second water draining pipe or feeding the processed water from the lower washing tub unit to the upper washing tub unit through the first connection hose.

17. The drawer-type washing machine according to claim 16, wherein each of said first and second flow control devices is a pump.

18. The drawer-type washing machine according to claim 1, further comprising:

a pressure sensor used for sensing pressure inside the washing tub unit;

a vapor exhaust port mounted to the top of said washing tub unit such that the port communicates with the interior of said washing tub unit, thus selectively discharging vapor from the washing tub unit to the atmosphere;

a solenoid valve mounted to the vapor exhaust port and used for controlling said port; and

a controller used for controlling the solenoid valve to open said vapor exhaust port when the pressure of the washing tub unit sensed by said pressure sensor is equal to or higher than a reference level.

19. A process of washing laundry using a drawer-type washing machine, with first and second cabinets respectively containing first and second washing tub units and set in a housing to be movable forward or backward relative to said housing, comprising:

a first step of determining whether the first washing tub unit is in its rinsing operation;

a second step of determining whether the rinsing operation of the first washing tub unit has been finished when it is determined at the first step that the first washing tub unit is in its rinsing operation, and a third step of feeding processed water from the rinsing operation of the first washing tub unit to the second washing tub unit when it is determined at the second step that the rinsing operation of the first washing tub unit has been finished;

a fourth step of determining whether the second washing tub unit is in its rinsing operation when it is determined at the first step that the first washing tub unit is not in its rinsing operation;

a fifth step of determining whether the rinsing operation of the second washing tub unit has been finished when it is determined at the fourth step that the second washing tub unit is in its rinsing operation; and

a sixth step of feeding processed water from the rinsing operation of the second washing tub unit to the first washing tub unit when it is determined at the fifth step that the rinsing operation of the second washing tub unit has been finished.

20. A process of washing laundry using a drawer-type washing machine, comprising the steps of:

sensing pressure induced by pressure head inside a washing tub unit after water is fed into said washing tub unit, and determining whether water inside the washing tub unit has reached a reference level;

turning on a heater to heat the water inside the washing tub unit when it is determined that the water has reached the reference level;

determining whether the pressure inside the washing tub unit has been increased equal to or higher than a reference level;

discharging highly pressurized vapor from said washing tub unit to the atmosphere when it is determined that the pressure inside the washing tub unit has been increased equal to or higher than the reference level;

determining whether the pressure inside the washing tub unit has been reduced lower than the reference level; and

stopping the vapor discharging action when it is determined that the pressure inside the washing tub unit has been reduced lower than the reference level.