Enhanced cycles for an automatic appliance

• US 5,669,983 A
• Filed: 06/08/1995
• Issued: 09/23/1997
• Est. Priority Date: 06/08/1995
• Status: Expired due to Term

• Current Assignee: Maytag Corporation (Whirlpool Corporation)
• Original Assignee: Maytag Corporation (Whirlpool Corporation)
• Inventors: Kennedy, Mary E., Corbett, Mitchell N., Cooper, Randall L., Cracraft, Mark A.
• Primary Examiner(s): Warden, Jill
• Assistant Examiner(s): Markoff, Alexander
• Application Number:
  US08/488,742
• Time in Patent Office: 838 Days
• Field of Search: 134/18, 134/25.1, 134/25.2, 134/25.3, 134/57 D, 134/56 D, 134/58 D, 134/10
• US Class Current: 134/18
• CPC Class Codes: A47L 15/0031 Water discharge phases
• CPC Class Codes: A47L 15/0034 Drying phases, including dripping-off phases
• CPC Class Codes: A47L 15/4297 Arrangements for detecting or measuring the condition of the washing water, e.g. turbidity
• CPC Class Codes: A47L 2401/023 Quantity or concentration of the consumable product
• CPC Class Codes: A47L 2401/08 Drain or recirculation pump parameters, e.g. pump rotational speed or current absorbed by the motor
• CPC Class Codes: A47L 2401/10 Water cloudiness or dirtiness, e.g. turbidity, foaming or level of bacteria
• CPC Class Codes: A47L 2401/12 Water temperature
• CPC Class Codes: A47L 2401/24 Spray arms status, e.g. detection of spray arm rotation
• CPC Class Codes: A47L 2501/01 Water supply, e.g. opening or closure of the water inlet valve
• CPC Class Codes: A47L 2501/02 Water discharge, e.g. opening or closure of discharge valve
• CPC Class Codes: A47L 2501/12 Air blowers
• CPC Class Codes: A47L 2501/30 Regulation of machine operational steps within the washing process, e.g. performing an additional rinsing phase, shortening or stopping of the drying phase, washing at decreased noise operation conditions

Abstract

An automatic dishwashing machine includes enhanced drying and draining cycles. Toward the end of the rinse and hold cycle when the water is draining, a second quantity of water is added to the machine resulting in a purging action which reduces the concentration of soil in the wash pump. During the normal wash cycle, if the dishwashing machine determines that the water is sufficiently dirty, a second drain is initiated to remove any dirty water that is present in the bottom of the pump after the first drain. During the dry cycle, the machine senses the temperature of the water and the presence of a rinse aid to select an appropriate dry cycle. The possible dry cycles include a delayed dry cycle and a pulsed dry cycle.

Claims

1. A method of removing soils from dishes in a dishwasher where there will be a delay until a washing cycle is initiated, comprising the steps of:

filling the dishwasher with a first quantity of water;

circulating the water in the dishwasher to rinse soil off the dishes;

initiating draining of the water from the dishwasher;

adding a second quantity of water to the dishwasher while continuing draining and before the first quantity of water has all drained from the dishwasher; and

draining the remaining first and second quantities of water from the dishwasher to reduce the soil concentration.

2. The method of claim 1 wherein the second quantity of water is added to the dishwasher when less than one minute is remaining in the draining of the water from the dishwasher.

3. A method of removing soils from dishes in a dishwasher in a pre-rinsing step where there will be a delay until a washing cycle is initiated, comprising the steps of:

filling the dishwasher with a first quantity of rinse water having no detergent;

circulating the rinse water in the dishwasher to rinse soil off the dishes;

initiating draining of the rinse water from the dishwasher;

adding a second quantity of rinse water having no detergent to the dishwasher while continuing draining and before the first quantity of rinse water has all drained from the dishwasher; and

draining the remaining first and second quantities of rinse water from the dishwasher.

4. A method of draining water and food soil from a dishwasher after a wash cycle but before any subsequent wash cycle in a dishwasher having a pump for pumping water from an area at the bottom of the pump to a drain using a siphon effect comprising the steps of:

initiating a first drain for a first period of time;

pausing for a second period of time to allow remaining water to collect at the bottom of the pump; and

initiating a second drain for a third period of time, wherein the first period of time is substantially longer than the third period of time.

5. The method of claim 4 further comprising the steps of:

sensing the amount of food soil present in the water in the dishwasher; and

selectively initiating the second drain depending on the sensed amount of food soil present in the water in the dishwasher.

6. The method of claim 5 wherein the amount of food soil present in the water is sensed using a turbidity sensor.