WO2006006126A1

WO2006006126A1 - A dishwasher and a method of washing dishware having baked-on food remains

Info

Publication number: WO2006006126A1
Application number: PCT/IB2005/052229
Authority: WO
Inventors: Aylin Akova Ersoy; Zehra Ulger; Songul Bayraktar
Original assignee: Arcelik Anonim Sirketi
Priority date: 2004-07-07
Filing date: 2005-07-05
Publication date: 2006-01-19
Also published as: TR200607358T1

Abstract

The invention relates to a dishwasher (1) and a washing method thereof that employs the washing programs to ensure the removal of the baked-on or dried food attached particulary to the metal surfaces of dishware like pots, pans, forks, or spoons. The main wash phase of a dishware washing programm is interrupted and high temperature steam is applied to the dishware.

Description

A DISHWASHER AND A METHOD OF WASHING DISHWARE HAVING BAKED-ON FOOD REMAINS

[001] This invention relates to a dishwasher and a washing method thereof. There are various methods of washing for removal of protein based baked-on food like burnt eggs, milk, minced meat , starch, oats and the like especially from metal surfaces. For example, a preliminary washing is conducted with the water taken in the machine, then a main washing program wherein the washing water is heated and cleaning chemicals are used followed by the application of rinsing and drying programs, a steam washing program is used in addition to the former programs for cleaning baked-on food. With the application of high temperature steam on dishware with baked-on food, the burnt, dried and hardened foodstains are loosened and separated from the surfaces they are attached to, but the desired performance can not be achieved for cleaning the dishware with very hard to remove baked-on food stains.

[002] In the American Patent no. US 4366005, a dishwasher is described where dishware is cleaned in a short time period with a washing profile comprising the steps of preliminary washing, steam washing, main washing and drying. Prior to the main washing cycle a steam washing process is conducted and the necessary hot water for the main washing cyle is obtained by heating water during the steaming application.

[003] In the American Patent Application no. US 2002078977 , in preparation for the con¬ ventional washing process, a steaming application is conducted for 15-20 minutes at a temperature of 100-150 ⁰C with a pressure of 15 psi.

[004] In the German Patent No. DE 4233996 , a mini dishwasher used at places like restaurants, bars and cafeterias which rinses and cleans small sized dishware hy- gienically in a short time with a mixture of steam-water and incorporates a cooling process immediately after cleaning for easy handling is described.

[005] In the European Patent Application No. EP 0291713 , preliminary washing, main washing, rinsing and drying programs are applied in a dishwasher wherein a steaming application is used for removing baked-on food on dishware and the steaming cycle is either applied before or in place of the preliminary washing program.

[006] The aim of the present invention is to realize a dishwasher and a washing method thereof that can remove baked-on food attached on dishware.

[007] The dishwasher and the washing method realized in order to attain above mentioned aim of the present invention is illustrated in the attached drawings wherein;

[008] Fig. 1 is a schematic view of a dishwasher.

[009] Each of the parts in the drawings are numbered as follows :

[010] 1- Dishwasher

[011] 2- Heater [012] 3- Circulation pump

[013] 4- Drain pump

[014] 5- Steam unit

[015] 6- Control unit

[016] The dishwasher (1) comprises a heater (2) for heating the dishwashing water, a circulation pump (3) for circulating the washing water, a drain pump (4) for removing the used water from the dishwasher after the washing process is completed, a steam unit (5) for the application of high temperature steam on the dishware for cleaning, the hard to remove, baked-on food and a control unit (6) for regulating the washing programs.

[017] The preliminary washing, main washing, rinsing and drying programs are performed at predetermined time intervals according to the user's choice in the dishwasher of the said invention. When the dishwasher is operated, if the user has chosen the program with preliminary washing, first the preliminary washing program is conducted followed by the main washing program. A while after the main washing program starts, the main washing program pauses and the circulation stops and preferably a pressurized high temperature steam of 100- 130 ⁰C is applied on the dishware for approximately 20 minutes by means of the steaming unit (5). When the determined time duration for the steam application ends, circulation starts again until the total predetermined time period for the main washing program is completed. Sub¬ sequently by employment of the rinsing and drying programs the washing programs terminate.

[018] The high temperature steaming application is conducted after circulation is performed for a period of time with the water heated to the required temperature for the main washing program and/or after circulation is made for a period of time with cleaning chemicals added water of the main washing program.

[019] In order to describe the washing method applied in the dishwasher (1), the washing and steaming temperatures are designated by the following symbols :

[020] T mainwashing : The water temperature for the main washing program. In the preferable application the temperature is approximately 48 ⁰C before the steam application. The temperature reaches 72-75 ⁰C after the steam application. [021] T steam : The temperature of the steam applied on the dishware. The preferred temperature is 110 - 130 ⁰C. [022] T rinsing : The temperature of the rinsing water in the hot rinsing ^<-- ste-p. of the rinsing^« program. Preferably it is approximately 58 ⁰C in the application. [023] The timing of washing programs is shown with the following symbols :

[024] t preliminary washing : The timing of the preliminary washing program . The preferred ap- plication is approximately 16 minutes. (It is approximately 16 minutes in the preferred application. ) [025] t main washing 1 : The duration of the main washing done prior to the steam application.

The preferred application is approximately 30 minutes. [026] t steam : The duration of the high temperature steaming application on dishware. The preferred application is approximately 20 minutes. [027] t mam washing2 : The duration of the main washing done after the steam application. In the prefferred application the duration is approximately 5 minutes if circulation is carried out during tmain washing 1 period prior to the employment of steam , and ap¬ proximately 35 minutes if circulation is not carried out during tmain washing 1 period prior to the employment of steam. [028] t πnsmg : The duration of the rinsing program . In the preferred application cold rinsing is carried out for approximately five minutes and following the drainage of cold water and intake and heating of water, hot rinsing is carried out for one minute. [029] The preliminary washing program comprises following steps :

- Intake of water into the dishwasher (1),

- Circulation during the t preliminary washing time period without heating or the use of detergents,

- Drainage of water at the end of the circulation step. [030] The main washing program comprises following steps :

- Intake of water into the dishwasher (1),

- Starting the main washing step with the circulation process that is conducted for a short time and supply of detergents into the washing tub,

- Heating up the water to T mamwashmg temperature and continuing the circulation during the heating step,

- Circulation with water that has reached T mamwashmg temperature for the duration of T mamwashmg 1 period,

- At the end of T mainwashingl period, stopping the circulation and pausing the main washing process,

- Application of steam at tsteam temperature on dishware during the t steam time period,

- After completion of the steaming application, restarting the main washing program and conducting the circulation during the T mainwashing2 time period,

- After the t mainwashing2 time period, ending the main washing program and stopping the circulation,

- Drainage of the washing water.

[031] The rinsing program comprises following steps :

- Intake of water into the dishwasher (1) ,

- During the t πnsmg time period first cold rinsing and afterwards drainage of water and water intake, application of hot rinsing after heating up the water to trinsing temperature,

- Ending the rinsing steps and drainage of the rinsing water.

[032] In another embodiment of the said invention, the steaming application within the main washing program is executed following the water heating step for the main washing program cycle. The main washing program comprises following steps in this employment :

- Intake of water into the dishwasher (1)

- Starting the main washing with the circulation process that is conducted for a short time and the supply of detergents into the washing tub during operation,

- After reaching to T mainwashing temperature , stopping the circulation and pausing the main washing process,

- Application of steam at t steam temperature on dishware for t steam time period,

- After completion of the steaming application, restarting the main washing program and operating the circulation during the T mainwashiπg2 period,

- After completion of the t mainwashing2 period, ending the main washing program and stopping the circulation,

- Drainage of the washing water.

[033] By interposing the application of high temperature steam process on the dishware in between the main washing program , the hard to remove baked-on food stains first come into contact with detergent added hot water in the main washing cycle and even if they cannot be removed entirely, their attaching resistance is partially weakened. Thus softened baked-on food stains again come into contact with detergent added hot water later within the main washing sequence and are completely removed from the surfaces they are attached to.

[034] With the correct timing of the high temperature steaming application, the removal of baked-on food stains from the dishware is achieved without the use of extra time,water or cleaning agents.

Claims

[001] A dishwasher (1) applying the preliminary washing, main washing, rinsing and drying programs in line with the choises made for washing the dishware, comprising a steam unit (5) applying hot steam on dishware for cleaning the hard to remove baked-on food on the dishware, and characterized by the application of hot steam on the dishware through the steam unit (5) a short time after the main washing program starts and continuation of the main washing program following the hot steam application.

[002] A dishwasher (1) as described in claim 1 characterized by the application of high temperature steam on dishware through a steam unit (5) after circulation is conducted for a short time with water heated up to the desired temperature for the main washing.

[003] A dishwasher (1) as described in claim 1 or claim 2 characterized by high temperature steam application on the dishware through steaming unit (5) following the circulation conducted for a while with washing water into which cleaning chemicals are added during the main washing .

[004] A washing method for a dishwasher (1) as described in Claims 1, 2 and 3 comprising the steps ; intake of water into the dishwasher (1); starting the main washing with the circulation process that is conducted for a short time and adding of detergents during this stage; circulation for t mainwashingl time period with water heated to t mainwashing temperature; at the end of t mainwashingl time period stopping the circulation and pausing the main washing; application of steam on dishware with t steam temperature for the duration of t steam time period; after the completion of the steaming process, restarting to the main washing and circulation for t mainwashing2 time period; drainage of the washing water

[005] A washing method for a dishwasher (1) as described in Claims 1, 2 and 3 comprising the steps; intake of water into the dishwasher (1); starting the main washing with the circulation process that is conducted for a short time and adding of detergents into the washing tub during this stage; heating up the washing water to t mainwashing temperature and circulation during the heating process; stopping the circulation and pausing the main washing process after reaching the t mainwashing temperature; application of steam on dishware with t steam temperature for the duration of t steam period; after the completion of the steam ap- plication, restarting the main washing and circulation for t mainwashing2 time period; ending the main washing and stopping the circulation at the end of the t mainwashing2 time period; drainage of the washing water.