GB2356555A - Fold up racks in a dishwasher - Google Patents

Description

2356555 DISHWASHER The present invention relates to a dishwasher,

particularly but not exclusively for domestic use.

It is known that the official performance of a dishwasher, including that declared on the energy label required by the European Union, is determined by the method specified in the EN 50242 standard, which is based on the use of what are called standard place settings.

However, the composition and/or types of articles to be washed during actual use are often very different from those of standard place settings. Consequently, every manufacturer wishing to satisfy the end user is obliged to design a generic machine, particularly the slidable elements (racks) for holding the articles to be washed, in such a way that these requirements are allowed for.

Among the known solutions GB-A-1227799 discloses making the upper rack in the form of a left section and a right section which can be inserted into corresponding frames cantilevered from the left and right walls of the washing enclosure and slidable independently of each other and of the lower rack in such a way as to emerge from the access opening of the enclosure. The said frames, with the corresponding rack sections, ran also be elevated by a few centimetres independently of each other and of the lower rack, in such a way that large articles such as trays and similar can be loaded on to the latter.

Although the sections of the upper rack are suitably removable from the machine, this is not true of the corresponding frames, which remain fixed to the corresponding walls of the enclosure, thus detracting from the convenience of use of the machine. Moreover, it is doubtful whether the washing efficiency will be high for the articles loaded on the upper rack sections, owing to the distance from the single spray arm which is present in this machine and which is located immediately above the base of the enclosure, in other words under the lower rack.

There is also disclosed in JP-A- 11047065 and JP-A- 11047065 a dishwasher which has an upper rack slidably integral with a lower rack in order to facilitate the loading and unloading of the articles to be washed when these are outside the enclosure. This upper rack is not only less deep (and therefore capable of holding relatively few articles to be washed) but also has.the characteristic of being movable between an operating position, in which it is essentially parallel to the lower rack, and an inactive position, in which it is rotated upwards through approximately 90 degrees and is positioned parallel to the side wall of the enclosure. The movement is carried out while the two racks continue to be slidably integral with each other, and enables large articles to be loaded onto the lower rack. However, this is achieved, in these circumstances, at the cost of the inability to use the upper rack and with the constraint of using a stationary spray unit, instead of a conventional and efficient rotary arm, to clean the articles loaded on to the upper rack.

According to the present invention there is provided a dishwasher comprising an essentially parallelepipedal enclosure and at least one structure for holding relatively small articles to be washed, wherein said at least one structure is cantilevered from a side wall of the enclosure, is slidable relative to said side wall, comprises associated means for spraying washing liquid, and is movable selectively between an operating position, in which it projects towards the mid-line of the enclosure, and an inactive position, in which it is positioned generally parallel to the wall from which it is cantilevered.

The hereinafter described and illustrated embodiment of dishwasher has a load capacity which can easily be matched to the articles of various composition and/or type which are to be washed, while providing a high washing efficiency according to the method of the aforementioned EN 50242 standard.

A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a front view of a dishwasher according to the invention; Figure 2 shows the same dishwasher in section along the vertical plane 11-11 of Figure 1; Figure 3 shows the same dishwasher in section along the horizontal plane 111-111 of Figure 1; Figure 4 shows an enlarged front view of the details of the dishwasher which are enclosed in the square referenced by the letter A in Figure 1; Figure 5 is similar to Figure 4, but shows details of the machine enclosed in the square referenced by the letter B in Figure 1, but omitting the articles to be cleaned which are shown in Figure 1.

It should be pointed out initially that many details of the dishwasher which are not strictly relevant to the present invention, and which are of types well known to those skilled in the art, have been deliberately omitted from the attached drawings for reasons of clarity.

With reference to Figures 1 to 3 in particular, a dishwasher comprises an external casing I and a washing enclosure 2, both being approximately parallelepipedal in shape.

The front access opening 3 to the enclosure 2 is shown as being open, but is closable by a door (not shown) which door can, for example, be of the conventional type hinged to the casing 1 along the lower edge of the opening 3, or slidable as shown in Italian patent application No. PN99AO00043 filed by the present applicant on 01.06.1999.

The parts of the hydraulic circuit of the dishwasher shown in the attached drawings are, in particular, a spray arm 4 associated with a rack 5 for holding articles to be washed.

The rack 5 is slidably mounted on suitable guides (also omitted for the sake of clarity) in the lower area of the side walls 6 and 7 of the enclosure 2. The rack 5, which can be conventionally manufactured from plastic-coated steel wire, therefore forms a first structure for holding not only plates P of standard size but also trays V of particularly large size - see Figure 1 - as will be explained in greater detail below.

The dishwasher further comprises other structures for holding articles to be washed (for example, cups T and glasses G - see Figures 1 and 3). These other structures consist of two shelves 20 and 30 which are supported by the side walls 6 and 7 respectively in the upper area of the enclosure 2. Since these shelves show mirror symmetry with respect to each other, their constructions are similar. Each shelf 20 and 30 comprises:

1. A first part 21, 31 in the form of a rectangular tray, made from moulded plastic material, with a flat base 22, 32 on which two spray arms 23, 33 and 24, 34 are located, one behind the other. The washing liquid is supplied to the arms 23 and 24, 33 and 34 of the respective shelves 20, 30 through pipes 25, 35 incorporated in the respective said parts 21, 3 1. Each said pipe 25, 35 comprises an inlet 26, 36 and two parallel branches 27 and 28, 37 and 38. Clearly, the overall diameter of the arms 23, 24, 33 and 34 is less than that of the arm 4 associated with the lower rack 5. Apertures 29, 39 are provided in the bases 22, 32 respectively of the shelves 20, 30 so as to allow the washing liquid draining from the articles G and T to fall into the base well 8 of the enclosure 2 (see Figures 2 - 5); and li A second part 41, 51 which consists of a support for the articles to be washed, in the form of metal bars with a peripheral frame 42, 52 for fixing to the parts 21, 31 respectively of the shelves 20, 30 (see Figures 2 and 3).

The shelves 20, 30 are fixed to corresponding brackets (of which Figures 4 and 5 show only those closest to the access opening 3, which brackets are referenced 45, 55) by means of pairs of pivots, 46 and 47, 56 and 57 respectively, slidable in suitable horizontal slots 48, 58 and vertical slots 49, 59. Thus the shelves can be moved, by simple rotation through approximately 90 degrees, independently of each other, between an operating position at a slight inclination to the horizontal (as shown in the square B in Figure 1) and a vertical position (as shown in the square A in Figure 1) to enable trays V and other large articles to be loaded on to the lower rack 4 of the machine. The brackets 46, 56 are slidable, together with the shelves 20, 30 respectively, along guides 61, 71, respectively, fixed to the side walls 6, 7 of the enclosure in such a way that, when the shelves are fully retracted into the washing enclosure 2, the aforementioned inlets 26, 36 engage with corresponding open branch pipes 62, 72 (located on the rear wall 9 of the enclosure 2 and provided with an associated and known one-way valve, omitted for the sake of simplicity) of the hydraulic circuit of the machine which also supplies the washing liquid to the lower arm 4 - see Figure 3.

The advantages of the above described preferred embodiment of dishwasher can be summarized thus:

a) the load capacity of the machine is essentially equal to that of an existing model with the same overall dimensions; b) because the shelves are movable independently of each other, the load capacity of the lower rack can be matched to actual requirements, in other words to the actual number of trays V and other large articles to be washed; C) it is only when the shelves are retracted into their operating position that the inlets 26, 36 are engaged with the open branch pipes 62, 72, enabling the arms 23 and 24, 33 and 34 of the shelves 20, 30 to be supplied with the washing liquid; and d) the proximity of the arms to the articles loaded on the shelves, such as 5 cups T and glasses G, enables the articles to be washed with high efficiency.

Although the above description refers to the currently preferred embodiment, persons skilled in the art will be able to envisage other constructions machines which can employ the invention in different ways without departing from the scope of the accompanying claims. 10

Claims (6)

1. A dishwasher comprising an essentially paraHelepipedal enclosure and at least one structure for holding relatively small articles to be washed, wherein said at least one structure is cantilevered from a side wall of the enclosure, is slidable relative to said side wall, comprises associated means for spraying washing liquid, and is movable selectively between an operating position, in which it projects towards the mid-line of the enclosure, and an inactive position, in which it is positioned generally parallel to the wall from which it is cantilevered.

2. A dishwasher as claimed in claim 1, wherein said at least one structure comprises a first part in the, form of a four-sided tray-like structure on whose base at least one spray arm is located, and a second part which acts as a support for the articles to be washed and which is spaced apart from and generally parallel to the base of the said first part.

3. A dishwasher as claimed in claim 2, wherein said tray-like structure is made in one piece of molded plastic and additionally comprises tubing which is arranged so as to be hydraulically connected to complementary means, which form part of the hydraulic circuit for supplying washing liquid and which are located on the rear wall of the washing enclosure, only when the structure is in the operating position.

4. A dishwasher according to claim 2 or claim 3, wherein at least one aperture is provided in the base of the said tray-like structure so as to allow washing liquid draining from any articles loaded on the corresponding second part of the said structure to fall into the well of the enclosure.

5. A dishwasher as claimed in any one of the preceding claims, wherein said structure is hinged, to supports slidable along a guide fixed to the corresponding side wall of the enclosure, by hinge means including a double pivot constructed and arranged to hold said structure stably in both of its operating and inactive positions.

6. A dishwasher substantiaHy as described herein with reference to the accompanying drawings.