EP1568304B1

EP1568304B1 - Dishwasher

Info

Publication number: EP1568304B1
Application number: EP05075336.7A
Authority: EP
Inventors: Erik Isaksson; Fredrik Dellby
Original assignee: Electrolux Home Products Corp NV
Current assignee: Electrolux Home Products Corp NV
Priority date: 2004-02-26
Filing date: 2005-02-11
Publication date: 2013-04-10
Anticipated expiration: 2025-02-11
Also published as: SE0400469D0; PL1568304T3; ES2420934T3; EP1568304A2; EP1568304A3

Description

This invention relates to a dishwasher comprising a wash chamber with one or several baskets supporting the dish to be cleaned, the wash chamber comprising one or several rotating wash arms spraying liquid on the dish, at least one of the baskets at a part of its area being provided with fixed spray nozzles
Conventional household dishwashers of the floor standing type are usually provided with two rotating wash arms, one placed below an upper basket and the other below a lower basket. The wash arms are spraying liquid upwards on the dish which is placed on the baskets above. The upper wash arm is, when the upper basket is inserted in the wash chamber, via a channel connected to a liquid inlet which is placed at the rear wall of the wash chamber whereas the lower arm is placed close to the bottom of the centre of the wash chamber. The wash arms are supplied with liquid from a circulation pump having an inlet in a trough shaped collecting container at the bottom of the wash chamber.
A disadvantage with this type of dishwashers is that the cleaning efficiency varies for different objects depending on that certain objects are difficult to place in such a position that the sprays from the rotating wash arm reach all the areas of the object. Also certain objects sometimes need a more intense washing procedure in order to be completely cleaned. To solve this problem it has been suggested to use nozzles that are placed in fixed positions on he baskets in addition to the rotating wash arm nozzles, see EP 997100 .
According to this publication the fixed nozzles might be turnably arranged such that they from an folded down, inactive position can be raised up and serve as an inner support for elongated, hollow object. Even if this type of holder serves well for a separate object the arrangement is not sufficiently good when it comes to objects of different shapes and configurations.
The purpose of our invention is to achive good cleaning results for different types of objects with the aid of a simple, flexible holder/nozzle arrangement that safeguards that the object is placed in a relevant position with respect to the nozzles. This is achieved by means of a device having the characteristics mentioned in the claims.
An embodiment of the invention will now be described with reference to the accompanying drawing on which Fig. 1 is a schematic perspective view of a dishwasher, Fig 2 is a perspective view of a dishwasher basket with the holder/nozzle arrangement, Fig. 3-5 are perspective views of the holder/nozzle arrangement different positions whereas Fig. 6 and 7 are vertical sections of a valve used in the liquid circuit.
The dishwasher shown in Fig. 1 comprises a box shaped wash chamber 10 having an opening that normally is covered by a lid 11. There is an upper and a lower basket 12 and 13 that can be pulled out from the wash chamber when the lid is open in order to fill the baskets with dish. At the bottom of the wash chamber there is a filter 14 that covers a liquid collecting container that is connected to a circulation pump (not shown). Below the lower basket 13 there is a rotating wash arm 15 connected to the outlet side of the circulation pump and having nozzle openings 16 directing the liquid sprays upwards against the dish that is placed on the lower basket 13.
The outlet side of the circulation pump is also via a liquid channel connected to an outlet (not shown) placed at the upper rear part of the wash chamber. Below the bottom of the upper basket 12 and fixed to it there is another wash arm (not shown) that rotates about a central hub and is provided with several nozzle openings through which liquid is sprayed upwards against the dish that is present in the upper basket. The hub is via a liquid channel, that is fixed to the upper basket and extends in the rearward direction from the centre, connected to said outlet when the upper basket is in its inserted position in the wash chamber.
The upper basket 12 is at its central, front part provided with a nozzle/holder arrangement 17. This arrangement comprises several fixed nozzles 18 having spray openings that are arranged at the bottom or below the bottom of the basket. The nozzle openings direct the liquid sprays mainly upwards and are connected to a distribution tube 19 arranged at the bottom of the basket. These fixed nozzles 18 are, as seen in a horizontal projection, preferably placed between the nozzle openings of the rotating wash arm below. The nozzles 18 are preferably of a well known type which, although they are fixed with respect to the basket, automatically direct the liquid sprays in different angular directions (within certain limits). The distribution tube 19 that extends to the central part of the basket 12 is via an inlet chamber 20 (see Figs. 6-7) and a fitting and a sealing arrangement (not shown) connected to the central hub that via said liquid channel is connected to the liquid outlet at the rear part of the wash chamber when the lower basket 13 is inserted in the wash chamber.
The inlet chamber 20 is separated from the distribution tube 19 by means of a valve 21. The valve is provided with a so called wax actuator 22 extending into the liquid at the inlet side of the valve and being provided with a piston rod 23 that becomes activated when the actuator has reached a certain temperature, preferably 50°-65°C. The piston is fixed to a valve body 24 that is lifted when said temperature has been reached such that a connection is established between the inlet 20 and the distribution tube 19. In order to return the valve body 24 to its original position when the temperature has decreased the valve body is under the influence of a spring 25.
The holder arrangement comprises two U-shaped parts 26 each having an elongated, waist elements 27 that is provided with several, parallel, flexible L-shaped arms 28. The U-shaped parts 26 are turnably secured at the end of each flange portion by means of pivot supports 29 arranged at a front and a rear plate 30 and 31 resp. The rear plate 31 is an integrated part of the valve 21 with the inlet chamber 20. The two U-shaped parts 26 can be set individually in a suitable angular position such as is illustrated in Figs. 3-5 and the positions can easily be chosen with respect to the objects being washed.
The holder/nozzle arrangement operates in the following manner. Normally the U-shaped parts 26 are in the position shown in Figs. 2 and 3 which means that the basket can be used in the normal way and that simultaneously elongated hollow objects or pots and pans can be placed on or above one or several of the arms 28 such that the nozzles 18 direct the sprays into the objects. During the initial washing procedure the dish is solely washed by means of the rotating wash arm whereas when the valve 21 opens (when a suitable temperature has been reached) cleaning liquid is also sprayed on the dish that is placed above the fixed nozzles. If the operator has hollow objects having a long narrow foot portion that should be placed vertically the U-shaped parts might be placed in the position shown in Fig. 4 in order to keep the objects in a safe position during the washing procedure. In this position also small objects like feeding baby's bottles can be pushed down between the flexible arms 28. In the position shown in Fig. 5 the U-shaped parts might serve as a support for larger elongated objects.

Claims

Dishwasher comprising a wash chamber (10) with one or several baskets (12,13) supporting the dish to be cleaned, the wash chamber comprising one or several rotating wash arms (15) spraying liquid on the dish, at least one of the baskets at a part of its area being provided with spray nozzles (18) characterized in that the spray nozzles (18) are fixed and that their openings are placed at or below the bottom part of the basket and that a holder arrangement (17) is provided above said area.
Dishwasher according to claim 1 characterized in that the holder arrangement (17) is flexible and arranged to support different kinds of dish.
Dishwasher according to claim 1 or 2 characterized in that the holder arrangement comprises at least an elongated element (27) that is mainly horizontal and that is turnably supported about a horizontal axis placed at a distance from and parallel to said element (27).
Dishwasher according to any of claims 1-3 characterized in that the holder arrangement (17) comprises two parallel elongated elements (27).
Dishwasher according to any of claims 3-4 characterized in that the elongated element is provided with branched off flexible, arms (28) or the like.
Dishwasher according to any of the preceding claims characterized in that at least one of the fixed nozzles is of such a type that it, when spraying occurs, automatically changes the spray direction.
Dishwasher according to any of the preceding claims characterized in that the nozzle openings of the fixed nozzles (18) are arranged such that the spray from at least one of these nozzles do not interfere with the sprays from the nozzle openings (16) of the rotating wash arm (15).
Dishwasher according to any of the preceding claims characterized in that the fixed nozzles (18) at their inlet side, via a temperature controlled valve, (21) are connected to a circulation pump arranged in the dishwasher.
Dishwasher according to claim 8 characterized in that the temperature controlled valve (21) is set to open when the liquid temperature exceeds 50°-65°C.
Dishwasher according to any of the preceding claims characterized in that the holder arrangement (17) is placed at the centre of the front part of an upper basket (12).