Washing machine with a titration indicator

• US 7,584,762 B2
• Filed: 12/23/2002
• Issued: 09/08/2009
• Est. Priority Date: 12/23/2002
• Status: Active Grant

• Current Assignee: Ecolab USA Incorporated (Ecolab, Inc.)
• Original Assignee: Ecolab, Inc.
• Inventors: May, Robert Eugene, Howland, David, Howes, Ronald Bruce Jr.
• Primary Examiner(s): Gakh; Yelena G
• Application Number:
  US10/328,497
• Publication Number:
  US 20040122558A1
• Time in Patent Office: 2,451 Days
• Field of Search: None
• US Class Current: 134/113
• CPC Class Codes: A47L 15/0055 Metering or indication of used products, e.g. type or quantity of detergent, rinse aid or salt; for measuring or controlling the product concentration
• CPC Class Codes: A47L 15/4293 Arrangements for programme selection, e.g. control panels; Indication of the selected programme, programme progress or other parameters of the programme, e.g. by using display panels
• CPC Class Codes: A47L 2401/10 Water cloudiness or dirtiness, e.g. turbidity, foaming or level of bacteria
• CPC Class Codes: A47L 2401/30 Variation of electrical, magnetical or optical quantities
• CPC Class Codes: A47L 2501/26 Indication or alarm to the controlling device or to the user
• CPC Class Codes: G01N 31/164 by electrical or electrochemical means

Abstract

A system and method is disclosed for indicating satisfactory times for titrating a chemical solution, e.g., cleaning product, used by a utility device to clean and/or sanitize various types of articles. The utility device is described in an exemplary embodiment as being a warewashing machine that applies the chemical solution to articles provided to the machine on racks. The chemical solution is formed in a solution tank from a combination of at least one chemical product and at least one rinse agent. Whereas the chemical product is described as a detergent, the rinse agent is described as water. Over a time period including multiple wash cycles, the chemical product and the rinse agent are added to the solution tank, thereby changing conductivity of the chemical solution. The present invention senses various types of information associated with the formation of the chemical solution and applies one or more test conditions to the sensed information to determine satisfactory time periods for measuring concentration of the chemical product relative to the chemical solution. Indications of the occurrence of these satisfactory times are presented on a display module in a manner visible to field persons responsible for titrating the chemical solution.

Claims

1. A system for indicating on a display device a time period for titrating a chemical solution contained in a solution tank of a utility device, thie system comprising:

a control module that determines whether sensed information associated with formation of the chemical solution in the solution tank satisfies one or more test conditions related to satisfactory times for titrating the chemical solution; and

a display module that displays a titration indicator upon satisfaction of each of the one or more test conditions.

2. A system as defined in claim 1, wherein the chemical solution comprises a chemical product and a rinse agent, and the control module defines a setpoint value associated with a desired concentration of the chemical product in the chemical solution.

3. A system as defined in claim 2, wherein the display device comprises a graphical user interface that enables a field person to select the setpoint value from a list of possible setpoint values.

4. A system as defined in claim 3, wherein the graphical user interface comprises an icon representing the titration indicator, and the graphical user interface displays the icon upon satisfaction of each of the one or more test conditions.

5. A system as defined in claim 2, further comprising:

means for sensing information related to a current concentration level of the chemical product in the chemical solution, wherein the sensing means communicates the information to the control module for determination of the current concentration level.

6. A system as defined in claim 5, wherein the control module compares the current concentration level to a predetermined threshold percentage of the setpoint value and marks the one or more test conditions as satisfied if the current concentration level of the chemical product relative to the chemical solution is less than the predetermined threshold percentage.

7. A system as defined in claim 5, wherein the sensing means comprises:

one or more conductivity cells located within the solution tank.

8. A system as defined in claim 5, wherein the utility device applies the chemical solution and the rinse agent to one or more articles during a wash cycle, and wherein the control module further controls dispensation of the chemical product into the solution tank.

9. A system as defined in claim 8, wherein the control module marks the one or more test conditions as satisfied if the current concentration level is less than a predetermined threshold percentage of the setpoint value and the chemical product is not being dispensed into the solution tank.

10. A system as defined in claim 8, wherein the control module further controls application of the rinse agent to the one or more articles.

11. A system as defined in claim 10, wherein the control module marks the one or more test conditions as satisfied if the current concentration level is less than a predetermined threshold percentage of the setpoint value, the rinse agent is not being applied to the one or more articles and the chemical product is not being dispensed into the solution tank.

12. A system as defined in claim 8, wherein the control module further detects whether the utility device is performing a wash cycle and marks the one or more test conditions as satisfied if the current concentration level is less than a predetermined threshold percentage of the setpoint value, the rinse agent is not being applied to the one or more articles, the chemical product is not being dispensed into the solution tank and the utility device is performing a wash cycle.

13. A system as defined in claim 12, wherein the utility device comprises a rinse module that applies the rinse agent to the one or more articles and a wash module that applies the chemical solution to the one or more articles.

14. A system as defined in claim 1, wherein the utility device is a warewashing machine that applies the chemical solution and a rinse agent to one or more articles being provided to a washing chamber of the warewashing machine on one or more article racks, wherein the chemical solution and the rinse agent are applied to the one or more articles over the course of a wash cycle associated with each of the one or more article racks.

15. A system as defined in claim 1, wherein the display module comprises:

a graphical user interface that enables a field person to control and monitor warewashing operations of the wash cycle for each of the one or more article racks.

16. A system as defined in claim 15, wherein the graphical user interface comprises an icon representing the titration indicator, and the graphical user interface displays the icon upon satisfaction of each of the one or more test conditions.

17. A method as defined in claim 1, wherein the display module comprises:

a light emitting diode (LED) through which a current is supplied to create the titration indicator.