EP0190675B1 - Washing machine with a water-softening device - Google Patents

Description

The invention relates to a washing machine according to the preamble of claim 1.

From DE-PS 15 85 797 a washing machine is known which is equipped with a softening device. The additional installation of a softener makes it possible to carry out the wash cycles with soft water and the rinse cycles with hard water. If soft water is available for the washing process, this has the advantage that a smaller amount of detergent can be used. Especially in areas that only have very hard tap water, it would be desirable to equip the washing machine with a softener.

While the use of a softening device has established itself in the dishwasher sector and is common, the installation of softening devices in washing machines has so far been of no practical importance. The reasons for this essentially lie in the fact that additional parts have to be accommodated in the already sufficiently filled housing of the machine and that the storage and addition of salt entails a further operating effort.

The invention has for its object to provide a washing machine in which the parts necessary for the softening device can be integrated into an existing washing machine concept within the housing and that the user still has easy handling and addition of the treatment agent. In addition to the softening device, additional precautions should be taken to achieve a further reduction in the detergent used.

This object is achieved by the features characterized in the main claim. Further features according to the invention result from claim 2. Advantageous configurations are listed in the following subclaims.

The advantages of the solution according to the invention are, in particular, that softeners which have been tried and tested from dishwashers have to be modified only slightly so that they are suitable for use in a washing machine and that the user still finds a central addition point on the machine where he can do all the washing - and fill in treatment agents.

The washing machine designed according to the invention is also characterized by a particularly economical consumption of detergent. No detergent can get into the drain system unused during the induction process.

Embodiments of the invention are shown purely schematically in the drawings.

• Fig. 1 in vereinfachter Form den Wasserführungsplan einer Trommelwaschmaschine mit einer Enthärtungseinrichtung,
• Fig. 2 ebenfalls den Wasserführungsplan einer Trommelwaschmaschine wie nach Fig. 1 mit zusätzlichen Vorkehrungen in den Ablauforganen zur Verhinderung von Waschmittelverlusten.

Show it:

• 1 in simplified form the water flow diagram of a drum washing machine with a softening device,
• Fig. 2 also the water flow diagram of a drum washing machine as shown in FIG. 1 with additional precautions in the drain elements to prevent loss of detergent.

The water supply to the machine is controlled by the solenoid valves (1) for cold water and the solenoid valve (2) for hot water from the program switch. The water chamber (3), the softener (4) and the salt vessel (5) are to be counted as essential for the softening device. As is known from dishwashers, the water chamber (3) is provided with an integrated back suction prevention. Depending on which control method is used for the amount of water for regeneration, the water chamber (3) can serve as a water storage container (gravity principle) or as a flow container (time control principle). The tub (6) of the machine receives the laundry drum (7) and is connected to the drain pump (9) via the tub drain (8). The detergent is added via the dispenser drawer (10).

The softener (4) is connected to the induction bowl (10) via a line (11). A branch (12) is interposed in this line (11), from which a connecting line (13) leads to the drain pump (9).

The softener (4) and the salt vessel (5) are connected to the water chamber (3) in the usual way via lines (14 and 15). In an advantageous embodiment, the filler neck (16) for the salt vessel (5) is guided into the upper lid area of the machine, it preferably being accessible to the user in the vicinity of the induction bowl (10).

2, in a further development of the invention, a buoyancy body (23) arranged in the tub drain (8) is arranged. A water reservoir (25) is formed in the drain line (24), which is attached within the machine housing at a location above the usual water level of the tub (6).

The function of the arrangement shown in FIG. 1 is as follows:

The washing process is carried out with soft water. For this purpose, warm or cold water or both mixed is passed through the line (19) into the water chamber (3). A water reservoir forms in this water chamber (3) and the softener (4) is acted on via the line (14). The soft water leaves the softener via the lines (17, 11) and is fed into the dispenser drawer (10), where the detergent for the pre-wash or main wash cycle is rinsed out and fed into the tub (6).

Since the entire rinsing program or at least the last rinse cycles are carried out with hard water, direct introduction into the tub (6) is carried out via the line (18) and the induction bowl (10). While the rinsing program is running, the regeneration process of the softener (4) takes place, advantageously during pumping between two rinsing cycles. For this purpose, the valve (20) is opened and the water stored in the water chamber (3) runs into the salt by gravity via the line (15) vessel (5) and presses a brine into the softener (4), in which the regeneration of the softener (4) begins. The residual water displaced from the softener runs directly through the line (17), the branch (12) and the line (13) into the drain pump (9).

Rinsing of the regenerated softener (4) is initiated by pumping out after the last rinse. For this purpose, fresh water flows through the line (19), the water chamber (3) and the line (14) through the softener (4) and presses the regeneration solution via the line (11) and the induction bowl (10) into the machine outlet. The softener is now available for the next soft water withdrawal of the subsequent wash cycle.

In the lines (11 and 13) or in the branch (12), valve arrangements that control the correct water path in the intended function can be switched on automatically or by the program switching mechanism.

A water hardness switch (21) on the water chamber (3) allows adjustment for different hardness ranges. As usual, the water chamber (3) is connected with a ventilation line (22) to the water inlet system of the machine for the purpose of ventilation.

In the embodiment shown in FIG. 2, the function white follows:

Here, too, the water supply to the water chamber (3) is controlled in the wash cycle via the magnetic valves (1 and / or 2). From here, the hard water is fed into the softener (4) in order to be fed from there as soft water via the line (11) and the open valve (26) into the induction bowl (10). The valve (27) in the connecting line (13) is closed. The detergent required for the washing process is flushed from the dispenser box (10) into the tub (6). During the flushing process, the drain opening of the tub (6) is closed by the buoyancy body (23). The residual water remaining in the drain line (24) and the water reservoir (25) from the previous washing program, after the drain pump (9) is switched off, presses the buoyancy body (23) into a sealing arrangement (not shown) in the tub opening. As a result, no detergent can get into the drain unused, so that smaller amounts of detergent can be dosed.

When the softener (4) is regenerated, the amount of water required for regeneration is made available in the arrangement in FIG. 2 by means of a time control of a solenoid valve (1) via a line (29). Via the water chamber (3), the water is pressed into the salt vessel (5) via the line (15), optionally via a valve (20) (not shown here), which is also provided. From there the brine then reaches the softener (4).

After regeneration of the softener (4), the regeneration solution is passed through the connecting line (13) to the drain pump (9) by a renewed burst of water. The valve (27) is open and the valve (26) is closed. In an advantageous embodiment, the valve (27) is switched on simultaneously with the drain pump (9), so that the regeneration solution rinsed out of the softener (4) is immediately conveyed out of the machine via the drain (28).

Instead of the valve (26), the valve (27) can also be designed as a 3-way valve in order to open or close either the line (13) or the line (11). This training serves the same purpose as the arrangement shown in Rg. 2.

Claims (10)

1. Washing machine having a detergent supply box and a water softening device, comprising a softening part, a replenishable salt container and a water chamber, which is to be filled with fresh water and has a means for preventing back-flow incorporated therein, which means is connected upstream of the softening part, characterised in that the softening part (4) and the salt container (5) are disposed in a lower region of the machine and are connected to the water chamber (3), situated there- above, by means of pipes in a manner known per se, in that the soft water outlet of the softening part (4) is connected to the detergent supply box (10), situated in an upper portion of the machine, by means of a pipe (11), and in that a branch (12) is fitted in this connection pipe (11) and a pipe (13) extends from said branch to the discharge system of the washing machine.

2. Washing machine according to claim 1, characterised in that the discharge system of the machine has a float (23), disposed in the wash solution container outlet (8), and a water reservoir (25) formed in the discharge pipe (24), and in that the float (23) is forced into a sealing arrangement, which is fitted in the solution container aperture, by means of the residual water remaining in the discharge members after the discharge pump (9) has been disconnected.

3. Washing machine according to claim 1 or 2, characterised in that valves (26, 27) are disposed in the branch (12) or in the pipes (11, 13) and are automatically controllable or are controllable by means of the programme controlling mechanism.

4. Washing machine according to claim 1 or 2, characterised in that the water chamber (3), which is connected upstream of the softening device (4, 5), is in the form of a water supply container, as is known per se, for supplying the quantity of regeneration water, which flows-in under gravity, or it is in the form of a throughflow container for the quantity of regeneration water, which is controlled with respect to time, and has a means for preventing back-flow incorporated therein.

5. Washing machine according to claims 1 to 4, characterised in that the regeneration of the softening part is controllable during the rinsing operation.

6. Washing machine according to claims 1 to 5, characterised in that the inflow of the quantity of water for regeneration purposes is controllable between two rinsing operations during the discharge pumping process.

7. Washing machine according to claims 1 to 6, characterised in that the rinsing-out of the regeneration solution is controllable in a discharge pumping step of one of the final rinsing operations, and in that the pipe (11) is closable by means of a valve (26), and the pipe (13) is opened by means of the valve (27).

8. Washing machine according to claims 1 to 7, characterised in that the valve (27) can be switched-on simultaneously with the discharge pump (9).

9. Washing machine according to claim 1 or 2, characterised in that the filler tube (16) of the salt container (5) extends to an upper region of the machine and is accessible from the supply box (10) or in the vicinity thereof.

10. Washing machine according to claim 1, characterised in that the branch (12) is disposed below the water chamber (3).

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