• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.2
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• pp.353-370
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• 2023

In this study, the performance of ultrasonic cleaners for ultrasonic washing, which is one of the wet cleaning methods, was evaluated. The washing performances of ultrasonic cleaners were compared with commercial washing machines under normal and wool courses based on different parameters such as detergency, wrinkle formation, fabric damage, dimensional stability, and germ removal ability. Cotton, silk and wool were used in this experiment. Results revealed that the ultrasonic washing detergency of cotton fabrics was lower than that of commercial washing machines under the normal course and similar to that of commercial washing machines under the wool course. Detergency of silk fabrics was similar under both normal and wool courses. In terms of wrinkle formation and dimensional stability, ultrasonic cleaners showed lesser wrinkles and lower shrinkage than commercial washing machines. Considering damage evaluation, ultrasonic cleaners more effectively removed soil without damaging fabrics compared with commercial washing machines. The bacteria removal rate of both cotton and silk was more effective than the wool course of a commercial washing machine. Thus, this study compares the performance of ultrasonic cleaners and commercial washing machines and provides meaningful results related to ultrasonic washing performance.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.5
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• pp.893-904
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• 1996

The main purpose of this research was to examine the purchase and use behavior of consumers related to washing machines in order to develope strategies to increase competitiveness of washing machines manufactured in Korea. Purchase and use behavior related to washing machines were examined by survey method and detailed information on washing conditions and usage of washing machines were obtained by diary method. 398 questionnaires were analyzed in the survey and 35 housewives participated in keeping the records of their washings for 30 days. The results of the survey showed that price and a tangle of clothes were the most determinant factors for purchase of washing machines and the knowledge related to washing was relatively low The diary method revealed that washing loads and frequencies of washing increase with the household size, and functions of washing machines except water level are infrequently used. Comparisons between the survey and diary results indicated that consistency between the two methods depends on the types of questions.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.1
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• pp.85-109
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• 2023

Laundry has traditionally been regarded as one of the most demanding household chores, but the introduction of smart washing machines is changing this perception. Although smart washing machines have been on the market for several years and consumers' perceptions of washing machines have changed, little is known about consumers' perceptions of smart washing machines. The purpose of this study is to determine what users expect from smart washing machines. We conducted two focus group interviews with sixteen participants who had used smart home appliances to acquire qualitative data. Stimuli created by the interviewees were applied in the focus group interviews to collect more insightful data. We analyzed the data using the three-step method and QSR NVivo. Analysis revealed ten categories of predictive expectations, including seven utilitarian attributes (i.e., smart functionality, smart user interface, reliability, controllability, interactivity, functional value, and economic value) and three hedonic attributes (i.e., fashionable value, psychological value, and social value). The results of this study have implications for the development of smart washing machines that would satisfy consumers by taking user expectations into account.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.996-1001
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• 2006

Automatic washing machines have been improved and popularized steadily since the first electric washing machine was produced in the early 1900's. Appliance industry has tried to obtain the performance of washing machine with large capacity, high energy efficiency, low vibration and low noise levels. As the installation peace of a washer becomes closer to the living space, vibration and noise problems become more important challenges. In general, a washing machine has four legs to support its body. Four legs of the washing machine should be attached on a floor. If not so, it may cause severe vibration or walking in the spin-drying process. Unfortunately, the floor of an ordinary house is bumpy in general, and the consumers will not accept bolting washing machines to a foundation; moreover, sometimes they move the location of their washing machines to utility rooms or bath rooms or kitchens and don't care for leveling the legs exactly. In this study, we devise an auto-leg system that prevents the occurrence of abnormal vibration and walking of washing machines. It is simply composed of a spring and a friction damper. Some experiments are implemented to show the dynamic characteristics of the three-dimensional auto-legged washing machine model that is located on the even or uneven ground. A spring parameter is optimized to adjust the length of the auto-leg system automatically up to 10 mm irregularity, and the friction damper is designed to decrease a resonance induced by the spring of the auto-leg system. Some numerical results show that placing the proposed auto-leg system in a washing machine makes good performance with low vibration, as well as low noise, regardless of the unevenness of the floor.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.11 s.158
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• pp.1589-1597
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• 2006

Nowadays, Korean consumers prefer drum-type washing machines to pulsator-type washers. Washing is a complex process involving the interaction of numerous physical and chemical influences. The main factors in the washing operations are the washing chemistry of the detergent along with the mechanical input, the wash temperature, and the time provided by the washing machine. Heavy-duty detergents that are used in drum-type washing machines contain different components from those used in vertical-axis washing machines. The bath ratio and the mechanical actions to which laundry is subjected are different between the drum-type and the vertical-axis washing machines. In this study we examined the effects of wash temperature, wash time, detergent concentration, and revolution speed on the removal of soils from artificially soiled cloths in a drum-type washing machine with heavy-duty commercial detergent. We used multiple regression analyses to find the relative importance of the factors and the optimum washing conditions. The results of these experiments showed that the washing temperature was the most important factor in the effective removal of most soils. This was followed by the washing time, the detergent concentration, and finally the revolution speed. In this study it was found that superfluous amounts of detergent did not sufficiently increase the soil removal rate. Koreans who are used to washing with cold water should increase the wash time to launder more efficiently.

• Journal of international Conference on Electrical Machines and Systems
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• v.3 no.2
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• pp.148-154
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• 2014

This paper describes problems of the sensorless starting of horizontal axis washing machines with direct drive and suggests solution, which was experimentally verified. Horizontal axis washing machines have very difficult conditions for the drive starting, especially at full load. Inertia of the tub and water, torque from the laundry make load torque at starting higher than rated one and sometimes even higher than the maximum torque of the motor, which makes sensorless starting extremely challenging task. This paper suggests modified open-loop starting, where control system is closed shortly after beginning at low speed and rotates the drum until laundry restructuring. To ensure proper work of the sensorless algorithm at low speed additional measures for increasing of the estimation algorithm performance have been taken. These measures include special algorithm for the drive parameters estimation, which has been developed and verified by the experimental results.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.2
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• pp.251-261
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• 1997

According to consumer's washing behavior, the washing efficiency of three different types of washing machines-pulsator, agitator, and drum was studied. Their detergency, rinsing efficiency, and the degree of fabric damage, tangle, and wrinkle were evaluated. The results showed that efficient washing capacity was different from the specified capacity of washing machine. Detergency and rinsing efficiency frere apparently decreased when more than 50% of capacity was loaded in washing machine of pulsator type, and 80% for agitator or drum types. They were also affected by detergent adding methods, and decreased in the order of water-detergent-washing load> washing load-detergent-water> washing load-water-detergent. Rinsing efficiency was significantly improved when the rinsing temperature was set above washing temperature. In addition, it was revealed that detergency, fabric damage, wrinkle, and tangle were highly correlated. The relationships between detergency and tangle were different for different types of washing machine. Positive relationships were found for agitator and drum types, whereas negative for pulsator type.

• Journal of KSNVE
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• v.7 no.2
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• pp.261-272
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• 1997

Recently washing machines are to be in lower vibration and lower sound because of better environment. Vibration problems in washing machines occur in both washing mode and spinning mode, but vibration in spinning mode becomes main problem because of its high rotating speed and continuity. Vibration while spinning is mainly due to rigid body motion of total washing system which includes suspending rods, washing bath, spinning bath, and gear sets. In this study, some researches were done in order to analyze the rigid body motion of washing system and flexible vibration of spinning bath. A basic mathematical model was established, and the effect of position of salt water and shape change of salt water case were considered. And the effect of lengths of suspending rods, attaching angles, vertical and horizontal position, stiffness of spring on the change of vibration were also considered. To identify the effect of salt water on vibration, some measurements were done. When salt water was positioned at upper part, the effect was most and this coincides with the tendency of simulation.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.13-15
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• 1997

Outer rotor type motors used in washing machines has some merits compared with ordinary rotor type motors. For example, the washing mchines' length can be shortened and stator coil length can be shortened.

• Proceedings of the Korea Society of Design Studies Conference
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• 2002.11b
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• pp.144-145
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• 2002