DE2210146A1 - Washing method to be carried out in a washing machine - Google Patents

Description

It is known that today's washing machines have a washing cycle which in the majority of cases comprises the following stages:

a) pre-wash (or soak) if necessary;

this is achieved when the washing drum is at a standstill or the washing drum is slowly driven with alternating direction of rotation and a large volume of water is supplied and the treatment is carried out at an average temperature of around 40 ° C the laundry in the presence of either conventional detergents or so-called biological detergents;

b) Washing process: the washing drum is rotated in alternating directions operated with a smaller amount of water at a temperature that depends on the fabric to be washed and this process is also carried out in the presence of conventional detergents;

c) a bleaching process (optional); this is done by introducing a metered amount of a suitable bleaching agent together with the first detergent, the laundry drum remaining set in rotation;

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d) Rinsing: This process is carried out while the drum is rotating and the water is released during the rinsing process drained several times and allowed Irish water, flushing itself with a large amount of water and, if necessary, after the water has been drained off, there is always an intermediate floor;

e) Final spin cycle: This is carried out after all the water has been sucked out; here the drum is in fast rotation, whereby the speed has to be based on the fabric of the laundry.

These stages can be combined in different ways in order to obtain different washing programs that are appropriate for each one Doing laundry can expect the best results.

It is known that the bleaching step has long been introduced in order to solve the problem of uneven whiteness of the laundry, because With the conventional washing processes, differences in the degree of whiteness could arise. So ea is already proposed have been to add some water to the wash liquor during the washing stage, which mixed with a suitable amount of a bleach before the addition of this bleaching agent, an equal amount of washing liquor was removed to the water level in the machine to keep in the same amount. This is followed by heating to bring the washing liquor with the bleach to the desired temperature To increase value.

There are other problems that have arisen in the past in that the so-called special fabrics (wrinkle-free fabrics, etc.), for which the washing processes were required, on the one hand require low temperatures and, on the other hand, cannot tolerate a bleaching stage, as otherwise the tissue would have been damaged.

In this context, it has already been suggested to use a cycle only for washing special fabrics (in the sense explained above)

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use, in which a washing stage is provided, the successive is carried out with two completely new solutions (i.e. with complete pumping of the first solutions at a specific Place of the washing process) at a temperature of about 35 ° C 45 ° C, whereby a dilution with fresh water takes place in the second washing stage before the washing process is finished.

These two washes actually correspond to the usual prewash and wash stages.

This method is obviously limited to the solution a very specific problem, and it is impossible to have a satisfactory fabric bleaching operation and it is also not possible to improve the effectiveness of the washing liquor, since the mere addition of fresh water without simultaneous supply of a detergent and without restoring the temperature of the washing liquor, neither with regard to the chemical activity is still satisfactory on the wash liquor.

In the following, the cycles will be considered in which a bleaching stage is provided, namely with water and one Bleach additive:

a) The bleaches are usually highly aggressive substances, so their use various safety precautions presupposes;

b) the use of bleaching agents is almost always impossible when it comes to colored fabrics and these As a result, the washing effect is limited to the actual washing process alone;

c) the cycle itself becomes even more complex, since at least two different types of detergent have to be used, namely a conventional detergent for prewash and for the actual washing process, and a bleach for the Bleach level.

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Also, the fact must not be overlooked that the detergency the washing liquor gradually decreases during the washing process.

The subject of the present invention is a novel washing process which makes it possible to use the conventional heat-active detergents in a conventional washing cycle for normal fabrics during all washing stages, the efficiency of the washing liquor never falling below a certain limit value, so that an improved Degreasing and stain removal is achieved both with colored laundry items and with a certain type of dirt, for example shirt collars. Another important object of the invention is to avoid the conventional e-leveling step and the use of special bleaching agents, while still achieving the same bleaching effect.

According to the invention this object is achieved in that in one normal cycle of a washing machine at the end of the conventional prewash stage and the washing stage a post-wash is carried out by adding a mixture of fresh water and the wash liquor is added to a heat-effective detergent of the type that has already been used during the normal washing process, wherein during this rewash, the temperature is again increased to the optimally effective value for the detergent in question.

This additional mixture is preferably supplied after a approximately the same volume of used wash liquor was sucked off.

According to a preferred embodiment, j $ 0 # to bO # are used Replaced washing liquor. If only such a mixture is added to the washing liquor in the laundry drum, without an equivalent To take the volume of used wash liquor, this additional wash liquor is approximately in terms of volume

It is important to note that the method according to the invention is different from the conventional method, namely one-

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on the one hand, because a single extinguishing agent for the whole
Washing process can be used and on the other hand arise
no more restrictions on the use of this cycle
on different tissues.

The method according to the invention is described below with reference to the drawing, for example. The only figure in the drawing shows
a graphical representation of the temperature of the wash liquor as a function of time.

It is said to be one cycle of an automatic washing machine more conventional
Type of construction are considered.

When the conventional prewash is completed, the temperature should be TP
be. At this point, fresh water is usually used with the
Starting temperature TP supplied and at the same time hereby a prescribed amount of detergent. Once the preselected water level has been reached in the machine, the drum will start rotating
initiated at the same time as the water is heated (time A). This heating is followed by curve 1 in the graphic
Representation until a higher temperature TS is reached. Now
the usual washing step is carried out by using the drum
comparatively low speed is alternately driven in both directions of rotation. This washing process could be shortened in suitable catfish as a puncture of the subsequent washing, which is a
A characteristic feature of the invention is "particularly in the case of certain special fabrics.

The water temperature during the washing stage is as shown by the curve 2 shown in the drawing, held at the value TS.

At moment B the post-wash stage is initiated and preferably At this point in time, the machine becomes a certain volume of water deducted. The machine is then filled with a preselected volume of cold, pure water at temperatures TP and

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along with this clean water becomes an additional, exactly dosed amount of detergent introduced. In order to ensure fully automatic operation of the machine, the is located for the Post-wash provided detergent preferably in a chamber that is separated from the chamber that receives the detergent for the usual washing stage. It is clear, however, that the usual detergent dispenser could instead be refilled with detergent after the washing stage has been initiated by the machine.

The addition of water and post-wash detergent causes a drop in temperature in the water according to curve 3 and this The temperature drops down to the value TI and at this point the heating elements should be switched on again to maintain the temperature to be brought back from the intermediate value TI to the value TS according to the curve 5

Such a heating level is important because when using the usual In detergents that are effective in heat, their effect is optimal when the water in the drum has a certain temperature depends on the detergent in question and also on the laundry itself. In any case, this is the optimum temperature above the temperature of the newly introduced fresh water.

It is clear that the temperatures TI and TS can be different depending on the particular fabrics to be washed. So will the temperature TS can be much higher with cotton, linen, hemp and similar fabrics, as the temperature TS with colored or synthetic fabrics. The temperature TI is automatically set as a function of the respective temperature TS and as a function on the amount of water that has been added.

In the conventional process that used a bleach is the re-heating of the water is not necessary, as it is known that the bleaching process can also be carried out with cold water.

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The recovery of the original water level, as mentioned above, with the removal of a certain amount of washing liquor and supplying an amount of water, by means of which the vias level is brought to the previous value, is advantageous, but not mandatory for the post-washing stage according to the invention.

Conversely, the adjustment of the water level in the drum is extremely important when using bleach, their Because of its aggressive nature, concentration must be precisely predetermined so that precise adjustment is required.

The post-washing stage is carried out in conjunction with a process which is the same as the washing process, i.e. in particular with the drum rotating at a low speed in alternating ei 'direction and that during the entire time which is determined by the curve part 6.

After completion of the post-washing stage (point C on the graphic representation), the water is drained from the drum and Rinsing and spinning are carried out in a conventional manner, whereby the temperature drops along section 7 of the illustration. The means required for the post-wash stage are the same, which are used during the washing process, i.e. must Pressure switch, a time cam, an electromagnetic valve and the like. Of course, the introduction of the Invention-related post-wash steps do not require the introduction of additional Purchases, falls which ^ should-be necessary. For example, if special Additives should be necessary, e.g. plasticizers or others Additives that are effective in the final rinse can do so without changing the wash cycle and there can be those Means are used that exist in the usual washing machines are.

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The main advantage of the post-wash cycle according to the invention is that the use of dangerous and corrosive substances is avoided and that a conventional washing machine detergent can be used to carry out the additional post-wash, which is adapted to the livestock to be washed, regardless of the type and color of the to be washed Objects are.

Of course, the amount of detergent and water used for the after wash as well as the temperature and duration of the rewash can be calculated to the optimum value in each case, taking into account different needs and with regard to the washing machine, especially with a view to a fully automatic one Operation.

Claims

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Claims (5)

Claims; 1. Washing process to be carried out in automatic washing machines, characterized, that after the washing stage, a further Naohwaschstufe inserted is, during the wash liquor clean water together with a detergent that is only effective under heat, which is also suitable for the Washing process is used, is supplied, and that the temperature of the washing liquor back to that for the detergent in question optimal value is increased. 2. The method according to claim 1, characterized, that the amount of clean water with detergent is 30 percent by volume does not exceed the washing liquor inside the water tank, 3. The method according to claims 1 and 2,
characterized, that before adding the mixture of clear water and detergent part of the wash liquor is drained in an amount that is the same as the amount of water supplied for the post-wash, so that the water level of the washing liquor in the washing drum remains unchanged. 4. The method according to claim 3, characterized,
that the amount of washing liquor removed and the amount of water supplied for the rewashing is 30 to 50 percent by volume of the total amount of water. 5. The method according to claim 4, _ * characterized in that that the detergent added during the after-wash is the same as that used during the washing process. 209838/0820 Blank page