Conveyor dishwasher and operating method for same

• US 20070023069A1
• Filed: 07/27/2006
• Published: 02/01/2007
• Est. Priority Date: 07/29/2005
• Status: Active Grant

• Current Assignee: Premark FEG LLC (Illinois Tool Works Inc.)
• Original Assignee: Premark FEG LLC (Illinois Tool Works Inc.)
• Inventors: Padtberg, Klaus, Disch, Harald, Berner, Dietrich, Litterst, Jurgen
• Granted Patent: US 7,938,913 B2
• Time in Patent Office: Days
• US Class Current: 134/25.200
• CPC Class Codes: A47L 15/241 the dishes moving in a horizontal plane

Abstract

A conveyor dishwasher includes a storage tank for holding sprayed final rinse liquid and a controllable liquid transfer device for transferring liquid from the storage tank to at least one wash zone as a function of a liquid demand in at least one of the wash zones.

Claims

1. A conveyor dishwasher for cleaning wares, comprising:

a conveyor device for conveying wares in a direction of conveyance through at least two zones of the conveyor dishwasher, including at least one wash zone and at least one final rinse zone, the wash zone having spray nozzles, a tank and a pumping device for recirculating wash liquid from the tank to the spray nozzles and spraying wash liquid through the spray nozzles onto wares, the final rinse zone including spray nozzles for spraying final rinse liquid onto wares;

a storage tank for gathering sprayed final rinse liquid;

a liquid transfer device for transferring liquid from the storage tank to the wash zone; and

a control unit configured for automatic operation of the liquid transfer device depending on liquid demand in the wash zone.

2. The conveyor dishwasher according to claim 1 further comprising at least one sensor device for determining liquid demand in the wash zone.

3. The conveyor dishwasher according to claim 2, wherein the at least one sensor device includes a turbidity sensor for detecting a predetermined degree of soiling of liquid in the tank of the wash zone, wherein the control unit operates the liquid transfer device when the degree of soiling in the tank of the wash zone is equal to or greater than the predetermined degree of soiling.

4. The conveyor dishwasher according to claim 3, wherein the at least one sensor device includes a liquid level sensor for detecting a predetermined lower level of the liquid in the tank of the wash zone, wherein the control unit operates the liquid transfer device when the liquid level in the tank of the wash zone is at or below the predetermined lower level.

5. The conveyor dishwasher according to claim 1, wherein the control unit operates the liquid transfer device for supplying liquid from the storage tank to the wash zone during initial filling of the conveyor dishwasher for initial filling of the tank.

6. The conveyor dishwasher according to claim 1 comprising multiple tanks associated with one or more wash zones, wherein the volume of the storage tank is no less than the sum of the volumes of the multiple tanks.

7. The conveyor dishwasher according to claim 1 further comprising a fresh water supply device that supplies fresh water to the storage tank, at least one sensor device provided for determining fresh water demand in the storage tank, wherein the control unit controls the fresh water supply device as a function of fresh water demand in the storage tank to supply fresh water to the storage tank when there is a demand for fresh water.

8. The conveyor dishwasher according to claim 7, wherein the at least one sensor device comprises a liquid level sensor for detecting a predetermined lower level of liquid in the storage tank, wherein the control unit operates the fresh water supply device and thereby supplies fresh water to the storage tank when liquid level in the storage tank is at or equal to the predetermined lower level.

9. The conveyor dishwasher according to claim 7, wherein the at least one sensor device comprises a turbidity sensor for use in detecting a degree of soiling of liquid in the storage tank, wherein the control unit operates the fresh water supply device and thereby supplies fresh water to the storage tank when the degree of soiling of liquid in the storage tank is equal to or greater than a predetermined degree of soiling limit.

10. The conveyor dishwasher according to claim 1, wherein the storage tank has an overflow over which liquid flows from the storage tank when liquid level in the storage tank exceeds a certain outflow level.

11. The conveyor dishwasher according to claim 1, wherein a bottom part of the zone in which final rinse liquid is sprayed has a storage tank opening which is connected by flow to the storage tank.

12. A method for operating a conveyor dishwasher, comprising:

providing the conveyor dishwasher with a final rinse zone for spraying final rinse liquid onto wares and a wash zone for spraying wash liquid onto wares; and

spraying wash liquid onto wares in the wash zone;

spraying final rinse liquid onto wares in the final rinse zone;

collecting sprayed final rinse liquid in a storage tank; and

supplying liquid from the storage tank to the wash zone as a function of demand for liquid in the wash zone.