Control technique for multistep washing process using a plurality of chemicals

• US 9,676,011 B2
• Filed: 08/29/2011
• Issued: 06/13/2017
• Est. Priority Date: 08/29/2011
• Status: Active Grant

• Current Assignee: Diversey Incorporated (Sealed Air)
• Original Assignee: Sealed Air Corporation (Sealed Air)
• Inventors: Pahlman, Tuomas
• Primary Examiner(s): Chaudhry, Saeed T
• Application Number:
  US13/220,190
• Publication Number:
  US 20130048024A1
• Time in Patent Office: 2,115 Days
• Field of Search: 134 10, 134 18, 134 252, 134 42, 68 1218, 68 17 R
• 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 15/0076 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 Class Codes: A47L 15/4287 Temperature measuring or regulating arrangements
• CPC Class Codes: A47L 15/4289 Spray-pressure measuring or regulating arrangements nozzles A47L15/4278
• CPC Class Codes: A47L 15/4291 Recovery arrangements, e.g. for the recovery of energy or water
• CPC Class Codes: A47L 15/4297 Arrangements for detecting or measuring the condition of the washing water, e.g. turbidity
• CPC Class Codes: A47L 15/4418 in the form of liquids A47L15/4409, A47L15/4436, A47L15/4445 take precedence
• CPC Class Codes: A47L 15/449 Metering controlling devices A47L15/4229 takes precedence
• CPC Class Codes: B08B 3/00 Cleaning by methods involving the use or presence of liquid or steam B08B9/00 takes precedence
• CPC Class Codes: B08B 3/08 the liquid having chemical or dissolving effect substances used, see the relevant classes
• CPC Class Codes: B08B 7/04 by a combination of operations
• CPC Class Codes: D06F 2101/00 User input for the control of domestic laundry washing machines, washer-dryers or laundry dryers
• CPC Class Codes: D06F 2103/20 Washing liquid condition, e.g. turbidity
• CPC Class Codes: D06F 2105/52 Changing sequence of operational steps; Carrying out additional operational steps; Modifying operational steps, e.g. by extending duration of steps
• CPC Class Codes: D06F 2105/60 Audible signals
• CPC Class Codes: D06F 34/22 Condition of the washing liquid, e.g. turbidity
• CPC Class Codes: D06F 39/088 Liquid supply arrangements

Abstract

Equipment and method for a system implementing a multistep washing process, with a chemical container (110A-110D) for each chemical (111A-111D) and means for conveying one chemical at a time from the container through a feed channel (120) to a washing object (100) and from the washing object through a return channel (130) back to the container. First and second sensors (122, 132) monitor a first parameter set in the feed channel (120) and a second parameter set in the return channel (130), respectively. Both parameter sets include parameter(s) indicating the purity of the chemical. A control center (150) includes calculation means (153) arranged to determine the mutual uniformity of the first and second monitored parameter sets. Action time of the chemical is determined on the basis of the mutual uniformity of the first and the second monitored parameter sets.

Claims

1. A method for optimizing a multistep washing process using a plurality of chemicals, the method comprising the following steps for at least one chemical:

conveying a chemical through a feed channel from a chemical container to a washing object and from the washing object through a return channel back to the chemical container;

monitoring, during conveyance of said chemical, a first parameter set in the feed channel and monitoring a second parameter set in the return channel, wherein each parameter set includes at least one parameter indicating directly or indirectly the purity of the chemical;

determining the mutual uniformity of the first and the second monitored parameter sets when the first parameter set and the second parameter set are similar within a predetermined threshold value; and

determining an action time of the chemical on the basis of the mutual uniformity of the first and the second parameter sets.

2. The method of claim 1, wherein the action time is determined in real time in the same washing process instance, in which said monitoring is carried out.

3. The method of claim 1, wherein the action time of the chemical is determined in non-real time by carrying out said monitoring in a plurality of washing process instances, and the action time determined thereon is used in one or more subsequent washing process instances.

4. The method of claim 1, wherein said parameter sets include absorbance of electromagnetic radiation or a quantity derived therefrom at least at one wavelength, the wavelength being within the range of 230 to 1100 nm.

5. The method of claim 4, wherein said parameter sets include absorbance of electromagnetic radiation or a quantity derived therefrom at a plurality of discrete wavelengths within the range of 230 to 1100 nm.

6. The method of claim 1, wherein said parameter sets include total absorbance of electromagnetic radiation or a quantity derived therefrom at least in one wavelength range whose upper and lower limits are between 230 and 1100 nm.

7. The method of claim 1, further comprising generating a signal indicating exhaustion of each particular chemical used if the absorbance measured in the feed channel exceeds a predetermined threshold value.

8. The method of claim 1, wherein said parameter sets also include at least one parameter, which is selected from a group consisting of electrical conductivity, temperature, pH and flow rate.

9. The method of claim 1, wherein the determination of the mutual uniformity of the first and the second monitored parameter sets comprises determination of the difference or ratio of said parameter sets.

10. The method of claim 1, wherein the determination of the mutual uniformity of the first and the second monitored parameter sets comprises the measuring of the first and/or the second monitored parameter sets correspondingly in a bypass pipe below the feed channel and/or the return channel.

11. The method of claim 10, wherein the chemical flow in the bypass pipe is temporarily interrupted for the duration of the measuring of the first and/or the second parameter sets for allowing gas bubbles to discharge.