EP0191729B1 - Washing machine - Google Patents

Abstract

The washing machine functions according to a new principle and contains the washable items, particularly washable textiles, in stacked layers in a mesh cage which is fixed in position at a drum rotatably mounted in a casing. Wash water as well as drying air flows through the preferably stationary or slowly rotating drum containing the washable items, is pumped off at an outlet of the casing, and returns again by way of a recirculation pipe to an inlet of the casing. Intermittent rotation of the drum, for example, by 180 DEG , is also possible. In this manner, the wash water or drying air passes through the washable items first from one side and then from the opposite side. All switching procedures are electronically controlled according to a preselected program schedule. The washable items no longer can be damaged by catching on the drum, the wash cycle is more effective and thus shorter than before, and electric energy and chemicals are saved.

Description

The invention relates to an automatic washing machine, in particular for washable textiles, which is set up for carrying out at least one cleaning and one rinsing process and, if appropriate, one spinner and one drying process, with a drum rotatably arranged in a housing for receiving the laundry, which is also used for washing Circumferentially distributed openings are provided for the inlet and outlet of the washing water, which is mixed with a detergent during the cleaning process.

The washing machines currently customary mostly have a lying washing drum which rotates periodically first in one direction and then in the other, the laundry being drawn through the water in the drum. As a result, it is heavily tumbled and even rolled up into lumps. It rubs off the holes in the washing drum, especially if it is embroidered, and if these are also sharp-edged, cracks or even holes in the laundry can easily occur. So-called gentle gears with slower rotary movements were therefore introduced, but the risk of clumping and chafing remains. Occasionally, in order to compensate for the slower movement, the detergents are added in larger quantities or those with a higher concentration, but the laundry is thereby attacked to an increased extent and the environment is polluted even more with the waste water.

The invention has for its object to provide an automatic washing machine in which the laundry is no longer damaged on the drum wall and which is also suitable for other laundry.

This object is achieved by the characterizing features of claim 1.

The automatic washing machine according to the invention allows a new, improved washing process to be carried out by holding the laundry in the drum during the entire cleaning and rinsing process, which washing water flows through continuously during the cleaning and rinsing process. A clumping of the laundry is prevented, which is now cleaned more uniformly and therefore more quickly, as a result of which less detergent is required and the time for the entire washing process and the energy requirement or expenditure are reduced. Furthermore, abrasion of the laundry is avoided, which enables cleaning delicate and even fragile laundry. If the drum is rotated by 180 ° from time to time during the cleaning and / or rinsing process, the washing water hits the items to be washed once from one side and the next, which also improves the cleaning or rinsing process and abbreviates. Where it is permissible, a spinning and / or drying process can end the washing process, for which all switching and dosing processes can be controlled electronically and set using a selectable time program.

• Fig. 1 den schematischen Aufbau eines Waschautomaten;
• Fig. 2 einen Gitterkorb für die Aufnahme des Waschgutes;
• Fig. 3 eine Trommel mit Antrieb.

In the accompanying drawing, an embodiment of the invention is shown with details. Show it:

• 1 shows the schematic structure of an automatic washing machine;
• Figure 2 is a mesh basket for receiving the laundry.
• Fig. 3 is a drum with a drive.

1 it is anticipated that individual auxiliary devices and most of the lines for the sake of clarity are shown outside the jacket surrounding the machine, while in fact everything is combined to form a compact unit. Furthermore, valves are arranged in practically all lines, which are not shown for the same reason as before.

In the roller-shaped drum 1, the grid basket 2 is inserted and conveniently fastened therein. The lattice basket is divided by lattice walls 3 in such a way that layers 4, which are filled with laundry in the drawing and parallel to the (not shown) axis of rotation of the drum, between which a laundry-free space 5 is left out, as can be seen more clearly from FIG. 2. The axis of rotation can be arranged horizontally or vertically and thus the drum with the mesh basket lying or standing.

The drum 1 with the mesh basket 2 is surrounded by the water and airtight housing 6, which has the inlet 7 and the outlet 8. The space 9 between the drum 1 and the housing 6 is divided by the walls 10. The entire washing machine is covered with the jacket 11.

From the outlet 8 to the inlet 7 of the housing 6, the recirculation line 12 extends into which the pump 13 and the additional heating device 14, for. B. an electrically or gas-heated heat exchanger are turned on. As a further heating option, the heating device 15 is built into the housing of the pump 13, preferably around its flow channel, in the form of a heating coil or heating elements, which can likewise be heated with gas or electrically. The outlet line 16 branches off from the recirculation line 12 and is equipped with the outlet valve 17 and a coarse filter 18 connected upstream of this valve.

In the corners between the housing 6 and the jacket 11 there is enough space to accommodate all auxiliary devices. The heat exchanger 19, which also has the function of a boiler and is therefore additionally electrically or gas-heated, is flowed through on the one hand by waste water which flows out of the housing 6 through the line 20, and on the other hand by Fri water that flows through line 21.

From the fresh water line 21 branches off the line 22, which leads to the containers 23, 24, 25 for powder-form detergent. A container 26 for liquid detergent can optionally or additionally be provided.

The heat exchanger 27 is flowed through on the one hand by the exhaust air, which emerges from the housing 6 as a partial flow or as a whole air flow into the surrounding atmosphere, as arrows 28 illustrate, on the other hand by fresh air as a replacement for the exhaust air, which flows in through line 29 and via the Line 30 opens into the recirculation line 12.

2 shows the empty lattice basket 2. The mutually parallel layers 4 formed by the grid walls 3 for the items to be washed with the spaces 5 free of items to be washed in between are clearly visible. Depending on the items to be washed, the wire mesh baskets have more or fewer wire mesh walls and, optionally, no items free of laundry items. The laundry is filled (in the drawing) from above, which can take place both in the assembled state inside the drum 1 and outside the washing machine.

Fig. 3 shows the drum 1, which is provided with openings 31 distributed over the circumference for the inlet and outlet of the washing water.

As already described with reference to FIG. 1, the mesh basket 2 can be inserted into the drum and fastened in it in rotation. The cantilevered shaft stub 32, on which the paddle wheel 33 is seated, is connected to the drum 1. Instead of the paddle wheel, deflection blades attached directly to the drum can also be provided. The initiation of the rotary motion is explained below. Of course, depending on the design of the washing machine, the drum 1 can be supported on both sides.

The entire washing process takes place as follows, with all switching processes being controllable in a known manner by a selectable electronic time program together or grouped together:

After the grid basket 2 has been filled with the laundry, fresh water is filled into the housing 6 through the line 21 via the heat exchanger 19 until the intended level is reached and a level controller (not shown) stops the supply of fresh water. The heat exchanger remains filled with water, which is achieved either by a shut-off valve or by an overflow arranged at the top.

Simultaneously with the filling of the housing, powdered detergent is flushed out of the container 23 or, when the washing machine is set up for such a supply, liquid detergent is injected from the container 26, which can be done by electrical, mechanical or hydraulic means.

After the filling process has ended, the pump 13 is started, which conveys the washing water from the housing outlet 8 through the recirculation line 12 to the housing inlet 7. In this flow path, the washing water would be easily heated, but is not common and is usually not necessary. The returned wash water entering at 7 is distributed in the space 9 between the drum 1 and the housing 6 and flows through the laundry to the outlet 8. So that it does not flow through the space 9 to the outlet 8 bypassing the laundry, these are Walls 10 provided. So already during prewashing, as in all subsequent processes, the items to be washed stand still relative to the drum and only the wash water is passed through.

At the same time the pump 13 is switched on, the rotating mechanism for the drum 1 is also switched on. The rotary movement can take place continuously, preferably slowly, in order to protect the laundry, save energy and give the washing water time to flow reliably through the laundry. Another advantageous possibility is to rotate the drum only intermittently, with longer breaks in between. Most conveniently, the drum is first placed in such a way that the laundry layers are perpendicular to the general direction of flow of the washing water through the drum. After a pre-programmable period of time, the drum is rotated by 180 ° so that the wash water hits the laundry from the opposite side. This process can be repeated any number of times. This results in an excellent cleaning effect even when prewashing.

After prewashing has ended, the dirty water is drained off via the recirculation line 12 into the drain line 16 when the pump is at a standstill. To protect the drain valve 17, the coarse filter 18 is provided in order to catch larger pieces which may be carried along and which could block or even damage the valve.

The prewashed goods, in particular laundry, can then be spun out in order to remove as much of the dirty water as possible.

To do this, the drum must run at a much higher speed than during prewashing. The drive could of course be carried out with its own small motor, but there are other options, namely the existing hydraulic means, which makes a motor unnecessary. To take advantage of this possibility, the paddle wheel 33 connected to the drum 1 is provided, which, for. B. is pressurized with pressurized water. All that is required is a residual amount of dirty water left in the housing, which is sucked in by the pump 13 and sprayed onto the paddle wheel. Full pressure is used for the fast rotary movement, while the supply line to the paddle wheel is throttled for the slow rotary movement. Extraneous water can also be used for this if it is in sufficient Amount and under sufficiently high pressure is available.

During the pre-washing and possibly subsequent spinning process, the fresh water in the heat exchanger 19, which serves as a boiler, is heated by external heating. For the subsequent cleaning process, hot water is now let in from the heat exchanger 19 into the housing 6 until the level controller switches off the supply. At the same time, powder detergent is flushed out of the container 24 or liquid detergent is injected from the container 26. Thereupon the pump 13 and the mechanism for the rotary movement of the drum 1 are switched on, which is rotated continuously or at intervals of 180 ° in a manner similar to that for prewashing.

The pump 13 sucks the washing water out of the housing 6 and conveys it back into the housing via the recirculation line 12, where it flows through the laundry and is sucked out again at the outlet 8. On the way through the recirculation line, it is heated to the desired temperature in the additional heating device 14 or — depending on which heating is provided — in the heating device 15 at the pump and is also kept at this temperature during the cleaning process.

Based on the fact that the degree of soiling of the laundry and thus the actual detergent consumption, hence the required concentration of the detergent in the washing water, is constantly decreasing in the course of the cleaning process, setpoint curves can be set for different types of laundry or laundry and different degrees of soiling the necessary concentration of the detergent is set up and entered into the washing machine. These curves, plotted over time, show a decreasing, towards zero course.

At pre-programmed intervals, the actual value of the concentration of the detergent in the washing water is measured, which in a known manner, for. B. with two electrodes acting as sensors, can be compared with the predetermined setpoint at this time and by adding fresh detergent, for which the liquid is particularly suitable, adjusted to the setpoint. Due to the course of the curve towards zero, practically all of the detergent entered is used up in the process described. The cleaning process is ended when the specified time of the selected curve has expired or after a specified minimum duration of the cleaning process the measured actual value exceeds the specified target value.

The detergent addition can also be controlled in other ways. The actual concentration value is measured from time to time and brought to a constant setpoint by adding detergent. As soon as the difference between the setpoint and actual value falls below a specified minimum, the cleaning process is ended.

The detergent consumption in the second-mentioned dimensioning method is greater than in the previous case, but is still much smaller than usual when working with a constant amount, which was often overdosed, in order to obtain reliably clean laundry. Now the laundry is protected more and the environment is less polluted. A combination of the two types of tax described is also conceivable.

Excessive contamination of the washing water during the cleaning process can be countered by temporarily or continuously draining a limited amount of the washing water and replacing it with fresh water from the heat exchanger 19. This wastewater can be discharged through the drain line 16, but it is more economical to pass it through the heat exchanger 19, where it gives off its heat to the fresh water, and then to discharge it through the line 20.

After the cleaning process has ended, all of the dirty water is drained off, which is preferably carried out through the heat exchanger 19 in order to at least partially utilize its heat in this way. In order to allow enough time for the heat exchange, the used warm water is advantageously drained slowly, which can be done with additional valves or with a small centrifugal pump. The laundry can also be spun before the washing process starts.

This is similar to the cleaning process. Fresh water is let into the housing 6 from the heat exchanger 19, which was heated by the previously drained wastewater, possibly by additional external heating.

The level controller controls the amount of fresh water that has run in, then shuts off the supply and gives the impulse for starting the pump 13, which presses the rinsing water through the laundry, sucks it off at the housing outlet 8 and conveys it back to the housing inlet 7 via the recirculation line 12. In this way it can be heated further by the heating devices 14 or 15, but depending on the items to be washed, little heated or even cold rinse water can suffice.

Also at the beginning of the washing process, the drum 13 is placed in such a way that the laundry layers are positioned perpendicular to the general direction of flow through the drum. From time to time the drum is rotated by 180 ° so that the rinsing water hits the layers of laundry from the opposite side. An occasional rotation of the drum only by 90 ° with a direct possibility for the rinsing water to flow through the wash-free spaces 5 can sometimes be expedient. An additional supply of wash water through a supply line opening into the housing 6 near the highest point can further increase the flushing effect.

The rinsing process is ended after a pre-programmed period of time. However, the remaining concentration of detergent can also be measured if the wash water is drained and a further rinsing process is initiated. In the last rinsing process, it is often useful to rinse a plasticizer out of the container 25 into the water. Intermediate spinning is also possible and increases the washing effect. In this way, a really clean and chemical-free laundry is achieved, which is particularly desirable and valued for laundry. In the case of items that are particularly difficult to treat, the cleaning and rinsing process can alternately be repeated two or even several times.

At the end of the last rinsing process, the water is drained and the laundry may also be spun. Now, if necessary or desired, a drying process can be connected, which is preferably done with heated air. This is pressed through the laundry, a partial flow can also - e.g. B. for loosening laundry - are fed from below, absorbing moisture, which is of course only possible to a certain degree of saturation. It must therefore be renewed from time to time or continuously.

In order not to constantly have to supply and heat the entire amount of air flowing through the laundry as fresh air, it is advisable to save heating energy by circulating the air in the housing 6 through a separate return line, similar to the washing water during the cleaning and rinsing process in which a fan is switched on. It is more advantageous to use the already existing recirculation line 12, which would also solve and simplify the question of heating by the heating devices 14 or 15 which can also be used for air. The pump 13 also presented a certain difficulty, but could be switched off, for example, by a bypass line with a fan.

But there is still a better solution. The pump can be constructed in such a way that it can also be operated at a much higher speed than when pumping water. It therefore acts like a fan and is suitable for conveying air.

With increasing saturation of the air with moisture, the drying effect gets worse. To avoid such a drop in effectiveness, z. B. after a predetermined period of time, the humid air is drained and replaced after a possible brief flushing phase with fresh air, which is heated on its way through the recirculation line 12.

An advantageous variant of this is that continuously moist warm air flows out through the heat exchanger 27, as indicated by the arrows 28. This exhaust air is replaced by fresh air, which flows through the line 29 to the heat exchanger and, after heating therein, reaches the recirculation line 12 through the line 30.

Another way to achieve dry air is to guide the humid air - similar to an air conditioning system - along its circuit via the artificially supercooled surfaces of another (not shown) heat exchanger, where the water vapor present in the air is partly condensed out. The condensate is drained and there is no need to renew the air. The energy expenditure for this above all. in the case of large washing machines, an advantageous process is generated in part as heat, which can be used to subsequently heat the air.

The drum is rotated continuously or intermittently even during the drying process. Since there is no longer any water in the machine, and the pump may also be required for air delivery, there is a way out that the paddle wheel 33 is subjected to a sharp jet of air, which is taken from the air flow. Such a jet is sufficient to slowly rotate the drum and the laundry, which is sufficient anyway. A single motor is therefore sufficient to operate the washing machine.

The washing process described can be varied and combined practically as desired in its individual phases. By pressing various push buttons on the washing machine, an electronic time program can be selected to adapt the washing process to the type and sensitivity, the degree of soiling of the items to be washed, which detects the rotary movements of the drum, the change or repetition of the individual processes, the renewal of the wash water or the Air, the dosage of detergents, the switching on and dimensioning of the heaters and the like, together controls.

The construction of the washing machine according to the invention allows the grid basket to be filled outside the machine and placed in a separate kettle filled with water for soaking. Of course, this can also be done in the washing machine itself by filling the housing 6 with water according to the first step of the prewash program. Soaking shortens the washing time in the machine, in particular prewashing, which can even be omitted entirely, which protects the laundry even more. It is advantageous to do the soaking during the day and the actual washing process with the cheap night electricity.

If the washing machine is used a lot, as is the case, for example, in laundries, then it is advisable to use two wire baskets turn. While the laundry in one basket is being washed, the laundry in the second basket is soaked, and so on. The wash cycles can then follow one another much more quickly, and there is then often hardly enough time available for heating the fresh water in the heat exchanger 19. Especially for this case, but also in general, it is advantageous to use the full electrical connected load when there is a small need for electrical energy during the washing process and to store it as available heat in the heat exchanger 19 serving as the boiler.

Claims (18)

1. A washing machine, especially for washable textiles, the functioning of which includes at least one wash and one rinse cycle and, if necessary, a spin and a drying cycle, the improvement comprising a rotatable drum to hold the washable items within a casing and which is provided with circumferentially distributed openings for the inflow and outflow of the wash water, to which a detergent is mixed during the wash cycle, the improvement further comprising the steps of:

- providing a drum in which the washable items remain stationary relative to the drum (1), whereas the drum turns in steps of a maximum of 180° either in continuous succession or intermittently;

- providing a means whereby during the wash and rinse cycles the wash water flows through the drum (1) continuously and at least approximately normal to its axis;

- providing a recirculation pipe with a pump installed in the flow path from the outlet of the casing to the inlet of the same, particularly for recycling of the wash water during the wash and rinse cycles.

2. A washing machine according to claim 1, and further comprising the step of: providing an open space between each pair of adjacent layers of washable items.

3. A washing machine according to claim 1, the improvement comprising the step of: providing a drain pipe from the recirculation pipe (16) which is provided with a drain valve (17) and ahead of which is attached a coarse filter (18).

4. A washing machine according to claim 1, and further comprising the step of: providing a heat exchanger (19) for the purpose of at least partially heating the fresh water and through which the waste water from the wash or rinse cycles can flow.

5. A washing machine according to claim 4, and comprising the step of: providing a heat exchanger (19) that can additionally be heated electrically or with gas.

6. A washing machine according to claim 1, and wherein are included (13, 14, 27) means for the purpose of providing warm air for the drying cycle.

7. A washing machine according to claim 6, and further comprising the step of: providing a means wherein the damp warm air from the drying cycle flows off through a heat exchanger (27) which serves, at least in part, for the heating of the fresh air.

8. A washing machine according to claim 6, and further comprising the step of: providing a means whereby the air circulating through the drum (1) and the recirculation pipe (12) in a closed dystem, after flowing through the drum flows through a heat exchanger with cooled surfaces on which the water vapor contained in the air partially condenses, and subsequently the air is heated before again flowing into the drum..

9. A washing machine according to claim 6, and further comprising the step of: providing a pump (13) in the recirculation (12) pipe which can also operate at a much higher speed than is required for pumping water, in order to serve as a fan for the air supply.

10. A washing machine according to claim 1, the improvement comprising the step of: providing a heater (15) in the casing of the pump (13) preferably around its flow channel.

11. A washing machine according to claim 1 and further comprising the step of: providing an impeller (33) located axially to the drum (1) and connected with it and which can be impinged upon by a water or air jet.

12. A washing machine according to claim 1, and further comprising the step of: providing a feed pipe flowing into the casing closest to its highest point in order to supply additional wash water from above during the rinse cycle.

13. A washing machine according to claims 1 and 6, and further comprising the step of: providing a means whereby the rotation of the drum (1), the change to the wash and rinse cycfes, or if desired, also to the spin and drying cycles, and the dosage of the detergent are simultaneously controlled by a selectable electronic program.

14. In a process for operating said washing machine according to claim 1, the improvement comprising the step of: providing a means whereby during the wash cycle the actual value of the concentration of the detergent in the wash water is measured at selected time intervals and is compared to a predetermined ideal value, and, if necessary, is matched to the said ideal value by the addition of detergent.

15. In a process according to claim 14, and further comprising the step of: providing a means whereby the ideal value of the detergent concentration is plotted as a curve against time.

16. In a process according to claim 14, and further comprising the step of: providing a means whereby the wash cycle is stopped and the rinse cycle started as soon as, after a predetermined minimum duration of the wash cycle, the measured actual value of the detergent concentration exceeds the predetermined ideal value.

17. In a process for the operation of a washing machine according to claim 1, the improvement comprising the step of: providing a means whereby during the wash process at least two wash and rinse cycles follow each other according to a preprogrammed interval.

18. In a process for the operation of a washing machine according to claim 1 and further comprising the step of: providing a means whereby the wash water at least during the wash cycle is supplied at least approximately normal to the layered (4) washable items by the appropriate positioning of the drum, and after a preprogrammed time interval the drum is rotated 180°, so that the wash water now flows through the washable items from the opposite side.

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