Fully automatic washing machine

• US 5,042,276 A
• Filed: 07/24/1990
• Issued: 08/27/1991
• Est. Priority Date: 08/02/1989
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Kamano, Toshiyasu, Hiratsuka, Hideaki, Ishikawa, Toshiichi, Shikamori, Tamotu, Ishino, Takashi
• Primary Examiner(s): Coe, Philip R.
• Application Number:
  US07/556,454
• Time in Patent Office: 399 Days
• Field of Search: 68/12 R, 68/23.3
• US Class Current: 68/12.04
• CPC Class Codes: D06F 2103/04 Quantity, e.g. weight or variation of weight
• CPC Class Codes: D06F 2103/18 Washing liquid level
• CPC Class Codes: D06F 2103/24 Spin speed; Drum movements
• CPC Class Codes: D06F 2105/58 Indications or alarms to the control system or to the user
• CPC Class Codes: D06F 33/40 of centrifugal separation of water from the laundry
• CPC Class Codes: D06F 34/08 Control circuits or arrangements thereof

Abstract

A fully automatic washing machine comprising a washing/dehydration basket, an agitator rotatably disposed inside the washing/dehydration basket, a motor for rotating the washing/dehydration basket or the agitator, a detector for detecting the amount of wash corresponding to the washing load, a detector for detecting the level of water in the washing/dehydration basket, and a control circuit for controlling operations of washing and dehydration processes. Water-reserved-starting of the dehydration process is effected in such a manner that dehydration is started while leaving a certain quantity of water in the washing/dehydration basket. The amount of cloth is detected by the cloth amount detector before the start of the washing process or at an initial stage of the same, and a value thus detected is stored in the control circuit. Washing water is discharged while reading a signal from the water level detector before the start of the dehydration process, thereby leaving a certain quantity of water corresponding to the cloth amount value previously stored.

Claims

1. A fully automatic washing machine comprising:

a washing/dehydration basket;

an agitator rotatably disposed inside said washing/dehydration basket;

a motor for rotating said washing/dehydration basket or said agitator;

cloth amount detection means for detecting the amount of load wash;

water level detection means for detecting the level of water in said washing/dehydration basket; and

a control circuit for controlling operations of washing and dehydration processes;

wherein water-reserved-starting of the dehydration process is effected in such a manner that dehydration is started while leaving a certain quantity of water in said washing/dehydration basket;

characterized in that there is provided with remaining water control means for controlling the quantity of remaining water at the time of starting of the dehydration process according to the amount of load wash.

2. A fully automatic washing machine according to claim 1, wherein the quantity of remaining water is increased when the amount of load wash is small.

3. A fully automatic washing machine according to claim 1, wherein when the amount of load wash is equal to a rated (maximum) value, the quantity of remaining water is zero or very small.

4. A fully automatic washing machine according to claim 1, wherein intermittent dehydration based on intermittently rotating said washing/dehydration basket is effected before dehydration based on continuously rotating said washing/dehydration basket.

6. A fully automatic washing machine according to any one of claims 1 to 5, wherein the quantity of remaining water is detected by said water level detection means.

7. A fully automatic washing machine according to any one of claims 1 to 5, wherein a plurality of dehydration holes are formed in said washing/dehydration basket, and said washing/dehydration basket is placed in an outer basket serving as a water reservoir.

5. A fully automatic washing machine comprising:

a washing/dehydration basket;

an agitator rotatably disposed inside said washing/dehydration basket;

a motor for rotating said washing/dehydration basket or said agitator;

cloth amount detection means for detecting the amount of load wash;

water level detection means for detecting the level of water in said washing/dehydration basket; and

a control circuit for controlling operations of washing and dehydration processes;

wherein water-reserved-starting of the dehydration process is effected in such a manner that dehydration is started while leaving a certain quantity of water in said washing/dehydration basket;

characterized in that there is provided with remaining water control means for detecting, with said cloth amount detection means, the amount of cloth before the start of the washing process or at an initial stage of the washing process, for storing a value thus detected, and for controlling the quantity of remaining water to be left before the start of the dehydration process according to said detected and stored value.

8. A fully automatic washing machine comprising:

a washing/dehydration basket;

an agitator rotatably disposed inside said washing/dehydration basket;

a motor for rotating said washing/dehydration basket or said agitator;

a cloth amount sensor for detecting the amount of load wash;

a water level sensor for detecting the level of water in said washing/dehydration basket;

a water supply valve for supplying water to said washing/dehydration basket;

a drain valve for discharging water from said washing/dehydration basket; and

a control circuit for controlling operations of washing and dehydration processes and driving of said motor, said water supply valve and said drain valve;

wherein water-reserved-starting of the dehydration process is effected in such a manner that dehydration is started while leaving a certain quantity of water in said washing/dehydration basket;

characterized in that the amount of cloth is detected by said cloth amount detection sensor before the start of the washing process or at an initial stage of the washing process;

a value thus detected is stored in said control circuit;

draining is effected by opening said drain valve before the dehydration process;

a reduction in the water level caused by draining is detected by said water level detection sensor; and

said drain valve is closed by an instruction from said control circuit when a signal representing the water level corresponding to the cloth amount value detected and stored is supplied from said water level sensor to said control circuit.

9. A fully automatic washing machine according to claim 8, wherein the detection of the amount of cloth by said cloth amount sensor is effected by alternately rotating said agitator in normal and reverse directions at short reversing time intervals and measuring the number of inertial revolutions caused by the normal and reverse rotation.

10. A fully automatic washing machine according to claim 9, wherein the detection of the amount of cloth is effected when the water level is lower than the level at which the washing process is conducted.

11. A fully automatic washing machine according to claim 8, wherein the agitation rotation of said agitator during the washing process is alternately reversed at short reversing time intervals, the wash is agitated with balancing water flows before draining at the end of the washing process, and said balancing water flows are formed at time intervals shorter than the reversing time intervals at which the rotation of said agitator is reversed in the washing process.