GB2063658A - Adjustable-volume metering reservoir for automatic dishwashing machines - Google Patents

Abstract

An automatic dishwasher is provided with an adjustable-volume metering reservoir (1) capable of being supplied with tap water for the regeneration of the water softener of the dishwasher and comprising a first chamber (2) communicating with the outside environment at its upper side and provided with an overflow device (5) and at least a second closed chamber (3) which is connected at its lower side with the first chamber (2) and extending upwards beyond the overflow level (A) of the overflow device (5). In order to adjust the amount of water dispensed from the reservoir, the second chamber (3) is capable of being opened at its upper side so that it can be filled with water up to said overflow level (A), rather than to the level (B) as happens when chamber (3) is closed. <IMAGE>

Description

SPECIFICATION Adjustable-volume metering reservoir for automatic dishwashing machines This invention relates to an adjustable-volume metering reservoir for automatic dishwashing machines.

As is known, dishwashing machines normally have a built-in water softener for the inlet water and this softener contains some active substances (ionexchange resins or the like), which must periodically be regenerated through the metered in-flow of a certain quantity of water that has been previously flowing through a proper salt container.

In the normal practice, the metering of the regenerating water is performed by an open-top reservoir, which is fed with tap water and is provided with an overflow at a predetermined level, this overflow being connected with the wash tub of the machine.

In this way means are provided for ensuring that a measured quantity of water will fill up the reservoir, whose bottom is connected to the salt container through a solenoid valve or the like.

When this valve is open, the metered quantity of water in the reservoir will, owing to the force of gravity, flow down through the salt container and into the water softener.

Since the volume of water required for this regeneration process is proportional to the degree of hardness of the supply water, mostdishwashing machines are provided with suitable means for adjusting the volume of water in the metering reservoir.

For example, such means may include a calibrated mass inserted to a greater or less degree in the reservoir to thereby vary the space remaining for water, or suitable devices for varying the overflow level of the reservoir, e.g. sliding baffles, specially shaped and height-adjustable portions of conduit, etc.

Considering the fact that this adjusting operation of the metering reservoir is to be performed only once, i.e. upon the installation of the dishwashing machine, such adjusting means are inherently too complex and expensive.

Furthermore, they are not quite convenient to use as their linear-type adjustment cannot always be performed with the due competence by the user and their setting can be accidentally altered.

According to this invention, there is provided an adjustable-volume metering reservoir, capable of being supplied with tap water for the regeneration of the water softener of a dishwashing machine, said reservoir comprising a first chamber communicating with the outside environment at its upper side and provided with an overflow device and at least a second closed chamber which is connected at its lower side with the first chamber and extending upwardly beyond the overflow level of said device.

When this is desired, said second chamber can be opened at is upper side in order to let it be filled with water up to said level, varying in this way the quantity of water which is collected into the reservoir. As will be apparent from the following description, the invention can provide a metering reservoir whose volume can be adjusted in a simple, effective and immediate way, being particularly convenient to use and not requiring any adjusting means.

The invention will be further described by way of non-limiting example with reference to the accompanying drawing, in which the sole figure is a diagrammatic cross-section of a preferred embodiment of the metering reservoir.

In the following, the illustrated metering device will be considered as installed in and connected to the water supply circuit of an otherwise conventional automatic dishwashing machine (not shown).

The reservoir is preferably made in the form of a flattened box 1 and is suitable for installation in the orientation as shown in the Figure.

The flattened box 1 basically includes a chamber 2, which is provided with an upper opening 4 (communicating with the outside environment), as well as with an overflow device 5, which is connected with the tube of the dishwashing machine through a conduit 6 and an opening 14 (both being integral with the box 1).

Adjacent to the opening 4 is located an air-break 7 provided in the water supply pipe 8 (diagrammatically shown) of the machine.

Upstream of the air-break 7, the pipe 8 is provided with a branch pipe 9, through which water can flow into the chamber 2. In this connection, a baffle 10 is placed between the opening 4 and the overflow device 5, said baffle being designed to direct the water losses from the air-break toward the conduit 6 and the water stream from the branch pipe 9 toward chamber 2.

The chamber 2 is preferably elongated along its vertical axis and shaped as shown in the Figure. it is equipped at its bottom with an outlet pipe 11, by means of which it shall be considered to be connected to the salt container (through a valveactuated device) and then to the water softener of the dishwashing machine. These devices are well known and therefore not shown in the Figure.

In particular, the valve-actuated device is closed when the water flows into the chamber 2 from the branch pipe 9 of the pipe 8, this latter being also equipped with controllable valve-actuated means (not shown).

The metering reservoir further includes at least one closed chamber 3, whose bottom communicates with the intermediate portion of the chamber 2 and which extends upwards beyond the overflow level A of the device 5.

This chamber 3 also is preferably formed as an integral part of the box 1, which can further include an opening 14 in order to connect the wash tub of the machine with the outside environment for vent ing purposes. The air-break 7 can obviously be enclosed in an open-bottom housing (not shown), in The drawing(s) originally filed was/were informal and the print here reproduced is taken from a later filed formal copy.

a known manner. In this case the lower opening of said housing can be joined to the opening 4 of the metering reservoirthrough an interposed sealing gasket.

The chamber 2, therefore, is vented to the outside environment only through the conduit 6 and the opening 12.

When the reservoir is supplied with tap water from the branch pipe 9, the same water is at first collected at the bottom of the chamber 2 and then its level will rise in the same chamber up to the overflow level A.

Since the top side of the chamber 3 is closed, an air bubble will be trapped under pressure in this chamber by the rising water. Owing to this fact, the same chamber is only partially filled with water, up to a level B which is lower than the overflow level A.

By suitably dimensioning the volumes of the reservoir, the water so collected in the chamber 2 and (partially) in the chamber 3 will correspond to the exact quantity required for the regeneration of the active substances of the water softener when the hardness of the supply water is not so high.

The regeneration process taken place in a known way by opening the valve associated with the outlet pipe 11, thus causing the waterto flow out of the metering reservoir due to the force of gravity. This water will at first flow through the salt container and then into the water softener.

Should a largerwaterquantity be requiredforthe regeneration process when installing the dishwashing machine, it will be sufficient to drill a hole in the upper side of the chamber 3, in order to vent the same chamber to the outside environment. The upper edge of the chamber 3 can to this aim be suitably shaped with an easily removable appendix 13.

When the chamber 3 is also open, the water, owing to the principle of communicating vessels, will flow into the reservoir, both into the chambers 2 and 3, until the overflow level A is reached.

The total quantity of the water collected in the reser voirwill therefore be in this case substantially larger.

The simple structure of the metering reservoir according to the invention, as well as its convenience of use, are quite apparent, since this reservoir does not require any complicated adjusting means, while at the same time it allows for a differentiated metering of the water volume requiredforthe regeneration of the water softener.

Claims (6)

1. An adjustable-volume metering reservoir, capable of being supplied with tap water for the regeneration of the water softener of a dishwashing machine, said reservoir comprising a first chamber communicating with the outside environment at its upper side and provided with an overflowflevice and at least a second closed chamber which is connected at its lower side with the first chamber and extending upwardly beyond the overflow level of said device.

2. A metering reservoir according to Claim 1, wherein the second chamber is capable of being opened at is upper side so that it can be filled with water up to said overflow level.

3. A metering reservoir according to Claim 1, wherein the upper edge of said second chamber is shaped with an appendix capable of being removed in order to permit said second chamber to be filled with water up to said overflow level.

4. A metering reservoir according to Claim 1, 2 or 3 wherein the first chamber communicates with the wash tub of the dishwashing machine through said overflow device and a connecting conduit and is arranged to receive the water to be metered through a pipe branching off the water supply conduit of the dishwashing machine, the water supply conduit being provided with an air-break adjacent to the top side of the first chamber, and including a baffle placed over said overflow device and capable of directing the water losses from the air-break toward said connecting conduit.

5. A metering reservoir for a dishwashing machine constructed and arranged substantially as herein described with reference to and as illustrated in the accompanying drawings.

6. An automatic dishwashing machine incor porting a water softener and a reservoirtherefor according to any one of the preceding claims.