Warewasher idling system and method

Patent metadata

Field	Value
Publication number	US-2017112349-A1
Application number	US-201615298421-A
Country	US
Kind code	A1
Filing date	Oct 20, 2016
Priority date	Oct 21, 2015
Publication date	Apr 27, 2017
Grant date	—

Abstract

A warewash machine for washing wares includes a chamber for receiving wares, the chamber having at least one spray zone. A spray system is provided in the spray zone for spraying liquid onto wares for cleaning. A tank captures sprayed liquid that falls within the spray zone. The tank includes a primary recirculation path for delivering liquid from the tank to the spray system, and a secondary recirculation path for delivering water out of the tank and back into the tank, without spraying within the spray zone, in order promote mixing within the tank.

First claim

What is claimed is:

1 . A warewash machine for washing wares, comprising:
a chamber for receiving wares, the chamber having at least one spray zone; a spray system in the spray zone for spraying liquid onto wares for cleaning; a tank for capturing sprayed liquid that falls within the spray zone, the tank including a primary recirculation path for delivering liquid from the tank to the spray system, and a secondary recirculation path for delivering water out of the tank and back into the tank, without spraying within the spray zone, in order promote mixing within the tank.

2 . The warewash machine of claim 1 wherein the primary circulation path includes a primary pump and the secondary circulation path includes a separate, secondary pump.

3 . The warewash machine of claim 2 , further comprising:
a controller operatively connected for controlling operation of the primary pump and the secondary pump, the controller configured such that, during a machine idling operation, the secondary pump is selectively operated for mixing of water within the tank while the primary pump is maintained OFF.

4 . The warewash machine of claim 3 , further comprising:
a heating element for heating liquid within the tank; wherein the controller is configured such that, during the machine idling operation, the heating element and the secondary pump are both turned ON and OFF simultaneously.

5 . The warewash machine of claim 3 , further comprising:
a heating element for heating liquid within the tank; at least one temperature sensor for indicating temperature of liquid in the tank; wherein the controller is configured such that, during the machine idling operation, the heating element and the secondary pump are both controlled at least in part based upon sensed temperature of liquid in the tank.

6 . The warewash machine of claim 5 wherein the controller is configured such that, during the machine idling operation, the heating element and the secondary pump are both controlled at least in part based upon whether sensed temperature of liquid in the tank is at a lower temperature set point and/or at an upper temperature set point.

7 . The warewash machine of claim 6 wherein the lower temperature set point is predefined and stored in memory and the upper temperature set point is predefined and stored in memory.

8 . The warewash machine of claim 5 , further comprising:
at least one spray zone temperature sensor for indicating temperature of air within the spray zone, wherein the controller is configured such that, during the machine idling operation, the heating element and the secondary pump are both controlled at least in part based upon sensed air temperature in the spray zone.

9 . The warewash machine of claim 1 wherein a common pump is located to selectively drive flow along either the primary circulation path or the secondary circulation path, a controller operatively connected for controlling operation of the common pump, the controller configured such that, during a machine idling operation, the common pump is selectively operated to flow liquid along the secondary recirculation path for mixing of water within the tank.

10 . The warewash machined of claim 9 further comprising:
a temperature sensor for indicating temperature of liquid in the tank and/or a temperature sensor for indicating air temperature within spray zone;
wherein the controller is configured such that, during the machine idling operation, the common pump is selectively operated to flow liquid along the secondary recirculation path based upon at least one of sensed temperature of liquid in the tank and/or sensed spray zone air temperature.

11 . A warewash machine comprising:
a chamber for receiving wares to be cleaned, the chamber having at least one spray zone and a liquid collection tank; a primary recirculation system for delivering liquid from the collection tank to a spray system for spraying liquid in the spray zone; and a secondary recirculation system for mixing liquid within the tank without passage of the liquid through the spray system.

12 . The warewash machine of claim 11 further comprising:
a controller configured to operate the secondary recirculation system during machine idling as needed to maintain tank liquid temperature, while flow through the primary recirculation system is maintained OFF.

13 . The warewash system of claim 11 wherein the primary recirculation system includes a primary pump, the secondary recirculation system includes a secondary pump, and the secondary pump is of smaller size and wattage than the primary pump.

14 . The warewash machine of claim 11 further comprising:
a temperature sensor for indicating temperature of liquid in the tank and/or a temperature sensor for indicating spray zone air temperature;
a controller configured to selectively operate the secondary recirculation system during machine idling based at least in part upon one or more of sensed tank liquid temperature and/or sensed spray zone air temperature.

15 . The warewash machine of claim 14 wherein the controller is configured to selectively operate the secondary recirculation system during machine idling based at least in part upon whether sensed temperature of liquid in the tank is at a lower temperature set point and/or at an upper temperature set point.

16 . The warewash machine of claim 15 wherein the controller is configured to selectively operate the secondary recirculation system during machine idling based at least in part upon whether (a) a difference between the upper temperature set point and sensed spray zone air temperature exceeds a predefined limit and/or (b) a difference between sensed tank liquid temperature and sensed spray zone air temperature exceeds a predefined limit.

17 . The warewash machine of claim 15 wherein the lower temperature set point is stored in memory and adjustable via a user interface of the machine and the upper temperature set point is stored in memory and adjustable via the user interface of the machine.

18 . The warewash machine of claim 11 wherein a common pump is located to selectively drive flow along either the primary circulation path or the secondary circulation path.

19 . A method of operating a warewasher including a spray zone with a liquid collection tank, the method comprising:
during cleaning operations flowing liquid from the tank along a spray recirculation system to spray liquid onto wares; during an idle operation selectively flowing liquid from the tank along a secondary recirculation path to mix liquid in the tank without spraying.

20 . The method of claim 19 wherein during the idle operation flow of liquid along the secondary recirculation path is controlled based at least in part upon one or more of sensed tank liquid temperature and/or sensed spray zone air temperature.

Assignees

• Illinois Tool Works

Inventors

• Anim-Mensah Alexander R
• Paulus Mary E

Classifications

• A47L15/0076

  of non-domestic use type, e.g. commercial dishwashers for bars, hotels, restaurants, canteens or hospitals (machines specially adapted for drinking glasses A47L15/0065; drawer-type dishwashers A47L15/0084; in-sink dishwashers A47L15/0086; miniature dishwashers A47L15/0089; conveyor-type dishwashers A47L15/24; machines with crockery cleaned by brushes A47L15/37) · CPC title

• A47L15/4219 Primary

  Water recirculation (A47L15/0078 takes precedence) · CPC title

• A47L2401/12

  Water temperature · CPC title

• A47L15/241

  the dishes moving in a horizontal plane · CPC title

• A47L15/0047

  Energy or water consumption, e.g. by saving energy or water · CPC title