GB2267429A - Dishwashers - Google Patents

Description

2267429 DISHWASHERS This invention relates to,dishwashers.

Dishwashers have of course been known for many years. In many countries including the UK they have achieved only limited sales. By way of example it has been estimated that in the late 1980's 46-,'j of US households but only 10% of UK households had dishwashers. A common perception -of the reasons for this is that such products are only purchased by members of social groups ABC1 and that even th;' have little interest in such products. y It is believed that this reasoning is fallacious. 'The inhabitants of the UK are notoriously keen on leisure time as-demonstrated for example by the very large time spent by many consumers watching television and video. The appetite seems almost insatiable and it is believed very surprising that automated washing-up has not been embraced more generally releasing at least some of the estimated 200-500 hours per annum spent on washing up to activities more widely perceived as pleasurable.

It is..believed that the reason why the dishwasher is not more widely used is lack of space. Social groups AB and to a lesser extent Cl are more likely to have larger kitchens or utility rooms than social groups D & E.

2 Consequently ABC1 consumers are more likely to be able to accommodate a dishwasher.

The average UK kitchen is small. Speculative builders, notable in the 1920's and 301s, built the cheapest houses they could. Small room sizes naturally were adopted as a means for reducing building cost. The kitchen was often constructed as small as possible consistent with accommodating a sink, cooker, and possibly fridge and/or boiler. Little room remains for the appliances introduced since that time.

It will bi- - noted 'that most kitchens have one so-called twet wall'. The wet wall is the one to which the sink, water, and waste pipes are attached. it is generally provided with a window. The automatic washing machine which 'is now almost ubiquitous requires water and waste pipes and hence is placed adjacent to the sink. The only remaining space is often too inaccessible to accommodate a-further appliance. It might be possible to replace the sink by a 'slimline' model but this is often not acceptable because of cost and trouble and because of the convenience of storing pans under the sink.

The va:lidity jof the above argument may perhaps be seen by noting that the microwave oven, a labour saving device which does not require a wet wall has been embraced whole-heartedly by the UK consumer with about half all 3 households now having at least one.

One possible solution is to provide a table-top dishwasher. The solution is not effective. First the unit occupies valuable working area. Secondly the unit is of small capacity. It is believed that dishwashers are only commercially acceptable if' they are able to take at least 6 table settings. Although some take 6 table settings, most table ton units take no more than 4. Finally table top units are often too expensive for the limited capacity they offer.

The solution according to the invention is to provide a dishwasher which can be suspended on a wall. The dishwasher of some embodiments of the invention may accept no more than 12 Internation Place Settings. The conventional perception is that such dishwashers would not be usable. The perception is fallacious as will be seen. First wall mounted appliances are commercially acceptable. By way of example central heating boilers are widely wall mounted and have been eagerly adopted by large sections of the public. It might be argued that the two are not directly comparable as lifting is required into and out of a dishwasher but not a boiler. This is true but it will be noted that up-right freezers and eye- level hobs are acceptable.

A number of features either alone or in conjunction 1 4 with others are preferred because they may enhance the usability of the dishwasher of the invention. They will be discussed by reference to the accompanying drawings of which:

Figure 1 is a front elevation of a dishwasher with the door opened; Figure 2 is an end elevation of the washer of Figure 1 mounted on the wall Figure 3 is an end elevation of a further washer mounted on a wall; Figure 4 is an end elevation of a washer with the basket lowered to the counter top (with the door omi tted) Figure 5 is a front elevation of a further embodiment of a dishwasher; Figure 6 is a cross-section on line x-x of Figure 5; and Figure 7 (a),(b) and (c) illustrate stages in raising baskets in the embodiment of Figure 5.

The apparatus shown generally at 1 of the invention may conveniently be skinned by a casing, for example, of plastics material or steel. The apparatus 1 is suspended on a wall 18 and has a door 2 giving access to the interior of the machine. Door 2 is preferably hinged at one side as shown, but may be hinged at the top. Preferably it is not hinged at the base because the door 2 would be difficult to close. Controls 3,8 are provided at the base of the unit. They can include an on- off switch, programme control, filters, water softener supply and so forth. Water and waste pipes (4) are also provided.

The size and shape of the unit is of some importance. Conventional floor mounted dishwashers are about 850 mm. high, 600 mm wide and 600 mm deep. Breadth is not a major consideration except that many wall units are of standard width, 300, 500, 600 or 1000 mm nominal. 600 mm is a popular width. It may be convenient to use this width too although wider or narrower dishwashers may be employed. Depth is however of great concern. If it is too deep the unit will project too far forward restricting access to a work surface below. If too shallow then the dishwasher capacity will be reduced too much. A depth of around 300 mm is preferred for conformity with standard kitchen wall units. It has been found that even a relatively short adult can fill a wall mounted unit 720 mm or even 850 mm high. A dishwasher set in a case of nominal dimensions 720 x 600 x 300 will be found to have a capacity for seven or eight place 6 settings yet still be fillable by an adult of normal or somewhat less than normal height. A 1000 mm width machine can also be provided having the capacity for 12 place settings. A washer for four or five settings can be obtained using a casing 500 mm high, 600 mm wide and 300 mm, deep.

In its simplest embodiment, baskets 6 for holding the crockery and cutlery are provided in the form of shelves which may be located in situ or loaded before locating on drawer runners provided in the side walls of the washer.

in a preferred embodiment of the invention the dishwasher is provided with lifting arms 7 to assist in moving the loaded. In the embodiment shown each side of the case of washer is provided with an arm 7. Both arms are pivotally mounted and preferably at least one is provided with drive means for driving the arm around the pivot. In a simple embodiment the arms may be undriven, the loaded basket being raised manually into position within the washer. Whereas if one or more of the arms is driven, the drive means will act as securing means to retain the basket within the washer, if the basket is raised manually, independent securing means is provided. This may for example be in the form of a simple catch 7 mechanism. In a straightforward driven embodiment the drive means can comprise a spring such as a coil spring. In other embodiments the arm can be driven hydraulically for example, via a dash pot or electromechanically by a stepper motor or a geared motor driving a drum.

The arm may be hydraulically driven using the water pressure from the cold water inlet. The other end of each arm is pivotally mounted to the basket above the centre of gravity of the basket preferably substantially above the centre of gravity. The basket thus depends from t-he arms and may be swung from a first position with the basket outside the washer and lower than in the first position. With an appropriate positioning of the washer relative to a work-surface the basket can rest on the work-surface 12 in the second position.

The drive means reduces or eliminates the effort required to raise and lower the basket into the washer. In this embodiment a single basket can be provided with two or more levels for placing articles to be washed. Alternatively, arms 7 may be mounted to a frame into which baskets may be placed.

In some embodiments of the invention a basket 6 is 8 provided with skids or wheels allowing it to be transf erred to or f rom the inner f ace of the door 2 f or loading and unloading.

It will be appreciated that in some embodiments door 2 need not extend as f ar as the upper basket 6 when the basket is in the second position and the door shut. This is useful in a small kitchen.

In other embodiments of the invention, separate baskets are lifted into and out of the washer and may, for example be provided with rollers for running on tracks on the inner side walls of the washer.

In a further preferred embodiment of the invention the lower basket is completely removable. The upper basket 6 is vertically movable between the first loading and unloading position and the second washing position. Preferably the movement is provided by hydraulic rams which can use the cold water inlet supply as a source of pressure fluid.

In order to have compact arrangement it may be that two pairs of hydraulic rams are "piggy-backed" as shown in Figure 7. In this arrangement a first pair of rams 13 carry a second pair of rams 14. Extension of the first 9 pair (Fig 7(a), (b))raises the second pair which may be extended to provide even greater reach (Fig 7 (c)). The pairs of rams may be extended sequentially or concurrently. A vertical guide rail 15 is preferably provided to ensure smooth vertical elevation of the basket. Stops 16 fixed to the interior of the dishwasher stop elevation of each pair of rams when the rams reach an appropriate level. Alternatively, telescopic hydraulic rams may be used.

In use the lower basket is removed and the rams caused by operation of control switch 17 to bring the upper basket to the first position. The basket may then be filled in situ or optionally after removal from the carrier. The filled upper basket is replaced and the rams actuated driving the upper basket to the second ption. The lower basket is then filled and placed in osi position. The door is closed and the machine caused to wash.

Most conventional dishwashers are square in plan. They are provided with a single spray arm (20) for each tray. Adequate coverage is obtained. Preferably in accordance with the invention a or each tray is provided with two spray arms. The washer of the invention is rectangular in plan and the use of two spray arms (20) results in more even coverage than would result from a single arm. In larger embodiments, the use of four spray arms may be preferable. A further advantage of this arrangement is that it allows operation in a "half load" mode, or even in a "quarter load" or "three quarter load" mode. In these modes articles to be washed would be placed in the basket(s) corresponding to the selection of 1/4, 1/2. 3/4 or full mode made via control knob 8 (Fig. 1) which in turn would actuate the respective spray arm(s).

This advantage would result in a reduction of electrical energy, water and cleaning and rinsing agents - providing reduced operating costs and effluent as compared with running a normal floor standing unit or say - 12 IPC settings.

A 7/8 place setting dishwasher of the invention (typically being 600 x 720 x 300 mm in size, complete with articles to be washed, water and cleaning agents typically weighs about 60 kg. It is perfectly feasible to spread such a load through the back plate which in turn distributes the weight on the wall. Most walls using the appropriate wall fixing can carry such loads.

In some embodiments of the invention a back plate 5 is mounted on the wall, for example, by bolts in wall-plugs and then the dishwasher mounted on the back-plate 5. There are many suitable methods of mounting the washer on the back-plate. In one embodiment the back-plate is provided with a pair of upwardly projecting flanges 10. The back-panel is provided with a pair of downward projecting flanges 11 engaging with the flanges of the back-plate to support the dishwasher. Alternatively one flange could be substituted by one or more strong points through which bolts 9 pass to secure the dishwasher to the wall.

Other changes and modifications will suggest themselves to those skilled in the art.

12

Claims (11)

CLAIMS:

1 A dishwasher suspendable from a wall comprising one or more baskets for holding articles to be washed, at least one of which baskets is movable between a first, loading and unloading position and a second, washing position.

2. A dishwasher as claimed in claim 1 wherein the first position is below the second position.

3. A dishwasher according to Claim 1 comprising at least one lift mechanism for raising and lowering a basket between said first position in the base of the dishwasher cabinet and said second position in a higher part of the dishwasher cabinet.

4. A dishwasher according to claim 3 wherein the lift mechanism is hydraulically operated.

5. A dishwasher according to claim 4 wherein the lift mechanism is hydraulically operated using the water pressure of the dishwasher water supply.

6. A dishwasher according to claim 1 wherein a single basket having a plurality of levels for receiving articles to be washed is mounted within the washing cabinet of the dishwasher by one or more arms each pivotally mounted at one end to the basket and at the other end to the interior of the cabinet; such that the basket is movable between the first, loading position 13 outside the cabinet and the second, washing position inside the cabinet.

7. A wall suspendable dishwasher.

8. A dishwasher according to any one of claims 1 to 7 suspended from a wall by means of a back plate securable to a wall and provided with one or more upwardly projecting flanges locatable in corresponding downwardly projecting flanges provided on the rear wall of the dishwasher casing.

9. A dishwasher according to claim 8 further comprising one or more bolts securing the rear of the dishwasher to the back plate.

10. A dishwasher according to any one of claims 1 to 9 further comprising two water spray arms for each basket.

11. A dishwasher substantially as illustrated herein with reference to the accompanying drawings.