EP3883447A1

EP3883447A1 - A dishwasher

Info

Publication number: EP3883447A1
Application number: EP19798262.2A
Authority: EP
Inventors: Yusuf Koc; Nasýr Efe ARAS; Tumay CITAK; Erkan KUTUK; Nese KILIC YAZAR
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2018-11-21
Filing date: 2019-11-04
Publication date: 2021-09-29
Anticipated expiration: 2039-11-04
Also published as: PL3883447T3; WO2020104177A1; TR201817561A2; EP3883447B1

Abstract

The present invention relates to a dishwasher (1) comprising a body (2); a washing tub (3) which is disposed in the body (2) and wherein the washing process is performed; a lower rack (4) which is disposed in the washing tub (3) at a position close to the base of the washing tub (3) and wherein the dishes to be washed are placed; a lower spray arm (5) which is positioned under the lower rack (4) so as to spray water to the lower rack (4); a heater (6) which is disposed under the lower spray arm (5) and which provides the heating of the air in the washing tub (3); and a casing (7) which covers the heater (6).

Description

A DISHWASHER

The present invention relates to a safely operated dishwasher.
In dishwashers, a washing cycle is completed by successively performing the prewashing, main washing, first rinsing, second rinsing and drying steps. The dishwashers generally comprise at least one rack whereon the items to be washed are placed and at least one spray arm which is positioned so as to spray water onto the rack. After the washing steps carried out with water, the water droplets and water accumulation on the dishes are removed by evaporation in the drying step. In the drying step, the temperature of the air in the machine is increased. In order to enable the heated air to rise and disperse in the washing tub, the heater is positioned closed to the base of the washing tub. Due to the high temperature of the heater, the components in the vicinity of the heater may be damaged. In the state of the art, a casing is used for covering the heater, thus preventing the components in the vicinity thereof from being damaged due to the high temperature of the heater. However, the spray arm spraying water onto the rack may stop at a position which cannot be known beforehand during the washing cycle. Therefore, the distance of the spray arm to the heater or the casing at the position the spray arm stops directly affects the effect of the temperature on the spray arm. As the distance between the spray arm and the heater or the casing decreases, the damage on the spray arm due to high temperature increases, which in turn adversely affects the washing performance.
In the state of the art International Patent Application Document No. WO2018108285, a dishwasher is disclosed, comprising a sensor which detects the rotational speed and the position of the spray arm.
The aim of the present invention is the realization of a dishwasher comprising a control unit which prevents the spray arm from being affected and damaged by the temperature of the heater.
The dishwasher realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof comprises a body; a washing tub which is disposed in the body and wherein the washing process is performed; a lower rack which is disposed in the washing tub at a position close to the base of the washing tub and wherein the dishes to be washed are placed; a lower spray arm which is positioned under the lower rack so as to spray water to the lower rack; a heater which is disposed under the lower spray arm and which provides the heating of the air in the washing tub; and a casing which covers the heater. In the dishwasher, in order to provide the proper hygiene by evaporating the water on the dishes to be washed, the heater heats the air in the machine and the drying step is performed at the end of the washing cycle. The temperature required for the efficient performance of said process is preferably determined as 70ºC by the producer. The heater providing the determined temperature value is disposed close to the base of the washing tub. A casing is provided over the heater so as to prevent the heater at high temperatures from damaging the spray arms and/or the components in the vicinity thereof.
The dishwasher of the present invention comprises a sensing element which detects the distance between the lower spray arm and the casing, and a control unit which enables the lower spray arm to be moved such that the distance between the lower spray arm and the casing is above a limit distance value predetermined by the producer depending on the data received from the sensing element. A certain distance must be kept between the lower spray arm and the casing in order to prevent the heater at high temperatures from damaging the lower spray arm. The control unit compares the distance data received from the sensing element with a limit distance value predetermined by the producer. In case the distance between the lower spray arm and the casing is below the limit distance value, the control unit enables the spray arm to continue moving. The control unit enables the spray arm to continue moving until the detected distance is above the limit distance value.
In an embodiment of the present invention, the dishwasher comprises a motion sensor which detects the movement of the lower spray arm and the control unit which activates the sensing element according to the data received from the motion sensor. During the washing cycle, the lower spray arm moves and sprays water onto the lower rack and stops at the end of the washing cycle at a position which cannot be determined beforehand. During the washing cycle, the lower spray arm may be positioned more than once such that there is a distance below the limit distance between the casing and the lower spray arm. Therefore, the motion sensor detects the movement of the lower spray arm, and only when the lower spray arm is detected to stop, the control unit activates the sensing element. Thus, the distance between the lower spray arm and the casing is determined, and the control unit compares the detected distance value with the limit distance value.
In another embodiment of the present invention, the dishwasher comprises a timer for determining the stop time of the lower spray arm according to the data received from the sensing element and the motion sensor. In case the lower spray arm is detected to stop according to the data received from the motion sensor, the control unit activates the sensing element as well as the timer. In case the motion sensor detects that the lower spray arm has stopped and the sensing element detects that the distance between the lower spray arm and the casing is below the limit distance value for a period of time longer than the limit period of time, the control unit enables the lower spray arm to be moved. In the preferred embodiment of the present invention, said period of time determined by the producer is 10 seconds.
In another embodiment of the present invention, the dishwasher comprises a temperature sensor which measures the temperature of the heater. The control unit activates the sensing element and the motion sensor depending on the data received from the temperature sensor. During the washing cycle, the heater is not activated at washing steps which do not require the heater. Therefore, since it is not possible for the lower spray arm to be affected and damaged by the temperature of the heater, the distance and lower spray arm movement information is not required. In case the heater is detected to be active depending on the data received from the temperature sensor, the control unit activates the sensing element and the motion sensor.
In another embodiment of the present invention, the dishwasher comprises the control unit which determines the limit distance value between the lower spray arm and the casing according to the data received from the temperature sensor. The control unit regulates the limit distance value between the lower spray arm and the casing according to the temperature data. Therefore, in case the heater has different temperatures, the limit distance value between the casing and the lower spray arm varies.
In another embodiment of the present invention, the dishwasher comprises an insulation element provided between the sensing element and the casing. Thus, the sensing element is prevented from being damaged due to the high temperature of the heater.
By means of the present invention, a dishwasher is realized, which comprises a control unit which regulates the limit distance between the lower spray arm and the casing according to the temperature of the heater.
The dishwasher realized in order to attain the aim of the present invention is illustrated in the attached figures, where:
Figure 1 - is the sideways perspective view of the dishwasher comprising the lower spray arm and the lower rack.
Figure 2 - is the front perspective view of the dishwasher comprising the casing.
Figure 3 - is the schematic view of the heater, the casing and the control unit which are disposed on the base of the washing tub.
Figure 4 - is the top perspective view of the part of the washing tub comprising the heater and the temperature sensor.
The elements illustrated in the figures are numbered as follows:

Dishwasher
Body
Washing tub
Lower rack
Lower spray arm
Heater
Casing
Sensing element
Control unit
Motion sensor
Timer
Temperature sensor
Insulation element

The dishwasher (1) comprises a body (2); a washing tub (3) which is disposed in the body (2) and wherein the washing process is performed; a lower rack (4) which is disposed in the washing tub (3) at a position close to the base of the washing tub (3) and wherein the dishes to be washed are placed; a lower spray arm (5) which is positioned under the lower rack (4) so as to spray water to the lower rack (4); a heater (6) which is disposed under the lower spray arm (5) and which provides the heating of the air in the washing tub (3); and a casing (7) which covers the heater (6). The drying step is carried out in order to evaporate the water remaining on the dishes after the washing steps carried out with water during the washing cycle. During the drying process, the air inside the machine (1) is heated by the heater (6) so as to evaporate the water remaining on the dishes. In order to enable the heated air to rise and disperse in the washing tub (3), the heater (6) is positioned closed to the base of the washing tub (3). Thus, the hot air is easily circulated inside the washing tub (3). In order to provide an efficient washing cycle, the temperature value is determined to be at least 55ºC by the producer. A casing (7) is provided which covers the heater (6) at high temperatures so as to prevent the same from damaging the spray arm (5) and/or the components in the vicinity thereof (Figure 1, Figure 2).
The dishwasher (1) of the present invention comprises a sensing element (8) which detects the distance between the lower spray arm (5) and the casing (7), and a control unit (9) which enables the lower spray arm (5) to be moved such that the distance between the lower spray arm (5) and the casing (7) is above a limit distance value predetermined by the producer depending on the data received from the sensing element (8). The lower spray arm (5) must be positioned at a certain distance from the casing (7) in order to be protected against the high temperature of the heater (6). The sensing element (8) detects the distance between the lower spray arm (5) and the casing (7). The control unit (9) compares the detected distance value with a limit distance value predetermined by the producer. In case the distance between the lower spray arm (5) and the casing (7) is below the limit distance value, the control unit (9) enables the spray arm (5) to continue rotating. The lower spray arm (5) is moved until the detected distance exceeds the limit distance value (Figure 3).
In an embodiment of the present invention, the dishwasher (1) comprises a motion sensor (10) which detects the movement of the lower spray arm (5) and the control unit (9) which activates the sensing element (8) according to the data received from the motion sensor (10). During the washing cycle, the lower spray arm (5) moves and sprays water to the lower rack (4). Therefore, while moving, the lower spray arm (5) may be positioned more than once such that there is a distance below the limit distance between the casing (7) and the lower spray arm (5). The motion sensor (10) detects the movement of the lower spray arm (5), and when the lower spray arm (5) is detected to stop, the control unit (9) activates the sensing element (8) (Figure 3).
In another embodiment of the present invention, the dishwasher (1) comprises a timer (11) for determining the stop time of the lower spray arm (5) according to the data received from the sensing element (8) and the motion sensor (10). Thus, the data received from the sensing element (8) is evaluated by the control unit (9) at the end of a limit period of time determined by the producer. In case the motion sensor (10) detects that the lower spray arm (5) has stopped and the sensing element (8) detects that the distance between the lower spray arm (5) and the casing (7) is below the limit distance value for a time longer than the limit time, the control unit (9) enables the lower spray arm (5) to be moved. In the preferred embodiment of the present invention, said period of time determined by the producer is 10 seconds.
In another embodiment of the present invention, the dishwasher (1) comprises a temperature sensor (12) which measures the temperature of the heater (6). In case the heater (6) is not active or the detected temperature is below the temperature value predetermined by the producer, the lower spray arm (5) cannot be damaged. Therefore, the information on the movement of the lower spray arm (5) and/or the information on the distance between the lower spray arm (5) and the casing (7) is not needed. In case the temperature detected by the temperature sensor (12) is above the limit temperature value predetermined by the producer, the control unit (9) activates the sensing element (8) and the motion sensor (10) (Figure 4).
In another embodiment of the present invention, the dishwasher (1) comprises the control unit (9) which determines the limit distance value between the lower spray arm (5) and the casing (7) according to the data received from the temperature sensor (12). For example, in case the temperature value detected by the temperature sensor (12) is 150ºC, the control unit (5) enables the lower spray arm (5) to be moved until the distance between the lower spray arm (5) and the casing (7) is X. In case the temperature value is 200ºC, the lower spray arm (5) is enabled to continue moving until the distance between the lower spray arm (5) and the casing (7) reaches a limit distance value which is above the X value.
In another embodiment of the present invention, the dishwasher (1) comprises an insulation element (13) provided between the sensing element (8) and the casing (7). Thus, the sensing element (8) is prevented from being damaged due to the high temperature of the heater (6).
By means of the present invention, a dishwasher (1) is realized, comprising the control unit (9) which enables the lower spray arm (5) to be moved such that the distance between the lower spray arm (5) and the casing (7) is above a limit distance value predetermined by the producer. Thus, the lower spray arm (5) is prevented from being damaged by the temperature of the heater (6) disposed under the casing (7).

Claims

A dishwasher (1) comprising a body (2); a washing tub (3) which is disposed in the body (2) and wherein the washing process is performed; a lower rack (4) which is disposed in the washing tub (3) at a position close to the base of the washing tub (3) and wherein the dishes to be washed are placed; a lower spray arm (5) which is positioned under the lower rack (4) so as to spray water to the lower rack (4); a heater (6) which is disposed under the lower spray arm (5) and which provides the heating of the air in the washing tub (3); and a casing (7) which covers the heater (6), characterized by a sensing element (8) which detects the distance between the lower spray arm (5) and the casing (7), and a control unit (9) which enables the lower spray arm (5) to be moved such that the distance between the lower spray arm (5) and the casing (7) is above a limit distance value predetermined by the producer depending on the data received from the sensing element (8).
A dishwasher (1) as in Claim 1, characterized by a motion sensor (10) which detects the movement of the lower spray arm (5) and the control unit (9) which activates the sensing element (8) according to the data received from the motion sensor (10).
A dishwasher (1) as in Claim 2, characterized by a timer (11) for determining the stop time of the lower spray arm (5) according to the data received from the sensing element (8) and the motion sensor (10).
A dishwasher (1) as in any one of the above claims, characterized by a temperature sensor (12) which measures the temperature of the heater (6).
A dishwasher (1) as in Claim 4, characterized by the control unit (9) which determines the limit distance value between the lower spray arm (5) and the casing (7) according to the data received from the temperature sensor (12).
A dishwasher (1) as in any one of the above claims, characterized by an insulation element (13) which is disposed between the sensing unit (8) and the casing (7).