Washing method and washing device

The invention relates to a method and a device for washing textile items to be washed, wherein the items to be washed and a washing liquid are introduced into a washing container. Then the washing container is dually asymmetrically centrifuged. During the dual asymmetrical centrifuging, the washing container is rotated about a first axis of rotation, which extends outside of the washing container, and simultaneously about a second axis of rotation, which extends through the washing container and is at an acute angle to the first axis of rotation. The washing process is thereby intensified and significantly accelerated.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the United States national phase of International Application No. PCT/EP2014/054421 filed Mar. 7, 2014, and claims priority to Switzerland Patent Application No. 593/13 filed Mar. 13, 2013, the disclosures of which are hereby incorporated in their entirety by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a method and a device for washing textile laundry items.

Description of Related Art

In the detergent industry, work is ongoing on the improvement of active washing substances, mixtures of substances and detergent formulations. The testing of the effectiveness of the active washing substances, etc. is thereby usually executed by means of test washings, whereby a washing fluid is prepared from the active washing substance or formulation, and then textile laundry items (substrate) contaminated in a specific manner are washed with this washing fluid under defined conditions (e.g. temperature). The washed textile items are then examined with regard to the effectiveness of the active washing substance under the applied conditions. In order to be able to examine as many active washing substances as possible in different formulations and concentrations, and in combination with different textile substrates, very large numbers of test washings are often required, which in total require a very large amount of time. This is undesirable, in particular for reasons of costs. A further disadvantage during the washing process—regardless of whether this occurs in research and development of washing products, or in the effective application itself—is that the washing methods of today's known art are normally based on significant mechanical actions on the washing items, as a result of which the latter become worn.

DE 102 06 620 A1 discloses a device and a method for testing the impact of fluids on a fabric, in which the fabric is arranged between two elements having depressions. The depressions form chambers in which the fluids to be tested are located. The elements, with the fabric located in between, are suspended on a shaft and are rotated for testing the impact of the fluids. In order to increase the fluid exchange between the chamber segments divided by the fabric, a small hole can advantageously be placed into the fabric in the wetted region.

Based on the above, the task underlying the invention is to provide a more efficient, very effective washing method requiring short washing times, as well as to provide a corresponding washing device for textile laundry items, which moreover lay the foundations for automated handling, and also do not have a negative influence on the laundry items being washed as a result of mechanical action. It should be possible to do without the placement of holes into the laundry items.

SUMMARY OF THE INVENTION

In its basic embodiment, the method according to the invention for washing textile laundry items comprises the following steps:Introduction of the laundry items and a washing fluid in a ready-to-use form, or in form of components, into a washing cell of a washing container, andDual asymmetric centrifugation of the washing container loaded with the laundry items and the washing fluid, whereby the washing container is rotated about a primary axis running outside of the washing container, and at the same time about a secondary axis running through the washing container and being arranged at an acute angle to the primary axis.

In the washing method according to the invention, the washing process takes place not primarily in a traditional manner by mechanical movement of the laundry items within the washing container, but on the basis of diffusion, i.e. by accelerated diffusion of the washing fluid through the laundry items and of the contamination out of the laundry items. The diffusion of the washing fluid is achieved by the combination of the acceleration forces caused by the dual asymmetric centrifugation in two different planes. By applying the principle of dual asymmetric centrifugation according to the invention, the washing process is intensified and significantly accelerated, so that the actual washing process only requires a very short amount of time (typically about 1 minute or less).

The secondary axis preferably runs as centrally as possible through the washing container, thus, in the case of a cylindrical washing container, through the cylindrical axis of the washing container. Thereby, imbalances are avoided as far as possible.

In accordance with an advantageous embodiment of the invention, the laundry items are arranged fixed or also planarised in the washing container and are washed in the fixed or planarised state. In particular the laundry items are spanned in the washing container for this purpose, such that within the washing cell of the washing container they are essentially fixed or planar. This causes that the laundry items are not crumpled as a result of the washing process itself. This has the advantage that after the washing process the laundry items are still fixed or planar and, therefore, can be examined directly and without any further preparation e.g. with regard to the washing results.

In accordance with a further advantageous embodiment of the invention, a washing container provided with two or more washing cells is used, into which washing cells the laundry items and washing fluid are introduced in each case. The use of such a washing container with several washing cells has the advantage that washing can be executed simultaneously in series in a single washing process.

Advantageously, a washing container is used thereby whose washing cells are arranged within the washing container in two or more planes. This allows the accommodation of many washing cells in a relatively small washing container, this is particularly advantageous if commercial centrifuges are to be deployed in which the size of the washing container is subject to limitations.

In accordance with a further advantageous embodiment of the invention, at least partially different washing fluids and/or at least partially different laundry items are introduced into the washing cells. This allows simultaneous test washings in series with different washing fluids and/or different laundry items.

In accordance with a further advantageous embodiment of the invention, an inert granular material, in particular in form of glass beads, is additionally introduced into the washing cell or the washing cells of the washing container. Thereby, the grains or beads, acting as washing bodies, increase the washing effect.

In accordance with a further advantageous embodiment of the invention, the temperature of the washing fluid in the washing cell or washing cells of the washing container can be controlled during the washing process. This can be implemented, for example, by heating means and/or cooling means provided in the washing container. Thus, the effectiveness of the washing fluid can be examined under various temperature conditions.

Alternatively, the temperature of the washing fluid in the washing container can also be adjusted to a desired set value before the washing process, and can then be held constant during the washing process, whereby the latter can be achieved by the deployment of a thermally insulated washing container.

Advantageously, the profile of the temperature of the washing fluid can be recorded during the washing process.

Advantageously, after the washing, the washing fluid is discharged from the washing cell or washing cells of the washing container by single-axis centrifugation. This has the advantage that the washed laundry items can be removed from the washing container in a practically dry state.

Advantageously, a washing container is used having at least one drainage opening that can be opened and closed, whereby the drainage opening is held open during the single-axis centrifugation.

It is particularly advantageous if the washing process is executed in a device centrifuging in a dual asymmetric manner about two axes, and, after the washing process, the discharging of the washing fluid is executed in the same device, wherein during the discharging of the washing fluid the device only centrifuges about one of the two axes.

With regard to the washing device, the essence of the invention consists in the following: A device for washing textile laundry items comprisesa washing container for accommodating the laundry items and a washing fluid in a ready-to-use form or in form of individual components, wherein the washing container has means for fixing the laundry items,means for mounting the washing container, andmeans for dual asymmetric centrifugation of the washing container about a primary axis and a secondary axis, wherein the primary axis runs outside of the washing container, and the secondary axis runs through the washing container and is arranged at an acute angle to the primary axis.

According to a preferred embodiment, the washing device is designed to be switchable between a first and a second mode of operation, wherein in the first mode of operation the washing container rotates about both axes, and wherein in the second mode of operation the washing container only rotates about one of the two axes, preferably about the primary axis.

According to a further preferred embodiment, the washing device has a first drive means for a rotative drive of the washing container about the primary axis, and a second drive means, which can be coupled with and decoupled from the first drive means, for a rotative drive of the washing container about the secondary axis.

Advantageously, the washing container is designed with at least one drainage opening, which can be closed and opened, for discharging washing fluid from the washing container.

Furthermore, it is advantageous if the means for fixing the laundry items are means for fixing the laundry items in a planarised manner.

Expediently, the washing container has two or more washing cells for accommodating the laundry items and the washing fluid.

The washing method according to the invention and the washing device according to the invention are in particular provided for the execution of test washings in the research and development of, for example, the detergent industry. However, they can also be applied to other washing processes in principle.

In the following, the washing method according to the invention and the washing device according to the invention are described in more detail on the basis of exemplary embodiments with reference to the accompanying Figures. It is shown in:

For the following description, the following definition applies: If in a Figure for purposes of figurative clarity reference signs are specified, but are not referred to in the immediately related part of the description, then reference is made to their explanation in preceding or following parts of the description. Vice versa, for purposes of avoiding figurative overload, reference signs less relevant for immediate comprehension are not inscribed in all Figures. Hereto, reference is made to the other Figures in each case.

DESCRIPTION OF THE INVENTION

The basic steps of the washing method according to the invention are represented inFIGS. 1 and 2.

In a preparatory step, according toFIG. 1, textile laundry items T which have to be washed are introduced into a washing container that is open initially. Likewise, a measured quantity of a washing fluid, either in a ready-to-use form, or in the form of individual components, is introduced into the washing container1. The washing container1typically has a cylindrical shape, and comprises a cup-shaped base section11and a cover section12. The axis of the washing container1is designated as1a. The interior of the washing container1forms a washing cell10.

The washing container1is then tightly sealed by placing the cover12onto the base section11. The means provided on both, the container and cover, for tightly fixing the cover are conventional and in the interests of simplicity are not represented. The closure of the washing container is not absolutely essential, depending upon the loading and shape of the washing container.

The following actual washing step is outlined inFIG. 2. Thereby, the closed (or, on occasions, open) washing container1, together with the laundry items T and the washing fluid W located inside it, are subject to a dual asymmetric centrifugation. This is to be understood to mean that the washing container1is simultaneously rotated about two axes of rotation A1and A2. The first, primary axis of rotation A1runs outside of the washing container1, such that the washing container1thus circulates as a whole on a circular path about the primary axis of rotation A1. This circular movement is indicated by the arrow P1. The second, secondary axis of rotation A2runs through the washing container1, and preferably coincides with the latter's own axis1a. The secondary axis of rotation A2is spatially oriented such that it includes with the primary axis of rotation A1an acute angle α of between 10° and 80°, preferably of between 20° and 70°, more preferably of between 30° and 60°, typically approx. 40°. Thus the washing container1also rotates at the same time about its own axis, wherein this rotational movement is indicated by the arrow P2.

The said dual asymmetric centrifugation is now executed for a predetermined washing time. By virtue of the centrifugal forces thereby occurring, acting in two different planes, the washing fluid W diffuses backwards and forwards multiple times through the textile laundry items T, whereby a very intensive washing action is achieved, in that the contamination diffuses very rapidly out of the laundry items and is homogeneously distributed in the washing fluid.

The rotational velocities about the two axes of rotation A1and A2are empirically adjusted such that on the one hand the centrifugal accelerations are as high as possible, and the washing durations (centrifugation durations) are as short as possible, but on the other hand the laundry items are not damaged. Values for the centrifugal accelerations from 30 up to 5000 m/s2, preferably from 2500 up to 3500 m/s2, are values that can be used in practice. Thereby it is possible to achieve washing times of about 1 minute, or even less.

After the dual asymmetric centrifugation, the washing container1is opened (inasmuch as it had previously been closed) and the washed laundry items T, together with the washing fluid W, are removed, whereby the washing fluid is usually disposed of or, if required, is also analysed e.g. as to how defined contamination is bound by the washing fluid, or what concentrations are present. The emptying of the washing container1can preferably be undertaken by means of centrifugation.

In the following, with the aid ofFIGS. 3 and 4, an exemplary embodiment of a washing device according to the invention that is particularly well suited to the execution of the method according to the invention is described in more detail, whereby only the functionally essential components of the washing device are represented in the Figures.

The washing device, the whole of which is designated as1000, is constructed in the form of a centrifuge and comprises a rotary plate1003, which can be rotationally driven by a motor1001via a shaft1002. An angled gear unit1004having an input shaft1005and an output shaft1006is arranged on the rotary plate1003. A washing container1is mounted in a socket1007made for accommodating the washing container, said socket is connected with the output shaft in a torque-proof manner and is sitting on the output shaft1006. An out-of-balance compensation weight1008is arranged under the rotary plate1003, diametrically opposite to the angled gear unit1004. The shaft1002driven by the motor1001passes through a coupling element1009being stationary with respect to rotation and said shaft passes through a pulley1010being free to rotate on the shaft1002. On the input shaft1005of the angled gear unit1004, a further pulley1011sits which is coupled with the drive shaft in a torque-proof manner. The two pulleys1010and1011are coupled with one another in terms of rotation via a drive belt1012. The axes of rotation of the shaft1002, or of the rotary plate1003, and of the output shaft1006of the angled gear unit1004, include an acute angle α and correspond to the primary and secondary axes A1and A2, respectively, seeFIG. 2.

The motor1001, the shaft1002, and the rotary plate1003form first drive means for purposes of the rotative drive of the washing container1about the primary axis A1. The angled gear unit1004, the output shaft1006, the input shaft1005, the pulley1011, the drive belt1012, and the pulley1009form second drive means that can be coupled with, or decoupled from, the first drive means for purposes of the rotative drive of the washing container about the secondary axis A2.

In the mode of operation of the washing device represented inFIG. 3, the stationary coupling element1009is connected with the pulley1010such that the latter cannot rotate. If the rotary plate1003rotates about the primary axis A1, the angled gear unit1004moves along a circular path about the stationary pulley1010, as a result of which the pulley1011is driven. Via the angled gear unit1004, the rotational movement of the pulley1011is transferred onto the socket1007made for accommodating the washing container, and thus onto the washing container1. In this mode of operation of the washing device, therefore, the washing container1rotates, as described in connection withFIG. 2, simultaneously about two axes, namely the primary axis A1and the secondary axis A2. The corresponding rotational movements are symbolised by arrows P1and P2, in an analogous manner toFIG. 2. In this mode of operation, the washing device represents a centrifuge operating in a dual asymmetric manner.

In the mode of operation of the washing device represented inFIG. 4, the stationary coupling element1009is decoupled from the pulley1010, which in the Figure is indicated by a position of the coupling element1009that is somewhat displaced axially. The pulley1010can now rotate freely on the shaft1002. The pulley1010now rotates together with the circulatory movement of the pulley1011, and can thus no longer drive the latter in a rotational manner. Thus, in this mode of operation of the washing device, the washing container1no longer rotates about the secondary axis A2, i.e. about its own axis, but only rotates about the primary axis A1, whereby the rotational movement about this axis is symbolised by the arrow P1. In this mode of operation, the washing device represents a traditional single-axis centrifuge.

The switching between the two modes of operation of the washing device is undertaken in a very simple constructional manner by the coupling, or decoupling, respectively, of the pulley1010and the coupling element1009. The coupling can, for example, be implemented electromagnetically.

A great advantage of the washing device according to the invention consists in the fact that both the washing step undertaken under dual asymmetric centrifugation and also the emptying of the washing container by traditional centrifugation can be executed in one and the same device, so that on the one hand no separate devices are required, and on the other hand handling is significantly simplified.

By a simple deactivation of the rotation of the washing container about one of the two axes A1or A2, preferably the rotation about the secondary axis A2, the switching is made from diffusion to centrifugation, that is to say, from a mixing of the content of the washing container caused by diffusion, to a separation of the washing fluid.

InFIGS. 5a-5dthe steps of the washing method according to the invention to be executed with the deployment of the washing device according to the invention are once again schematically summarised.FIG. 5ashows the preparatory steps in an analogous manner toFIG. 1. Here, a washing container301is deployed with a base section311and a cover section312, together with a washing cell310. In addition, the washing container is fitted with a drainage opening that can be shut off and which is symbolised by a valve315in the Figures. At the start of, and during, the washing process the valve315is closed.

FIG. 5bshows the washing container301in the closed state. The latter is inserted into the washing device according to the invention and dual asymmetrically centrifuged, whereby it rotates about the two axes A1and A2(FIG. 5c).

After the washing process has ended, the mode of operation of the washing device is switched from dual asymmetric centrifugation to a traditional single-axis centrifugation, whereby the washing container301only continues to rotate about the primary axis A1. During the switching of the mode of operation of the washing device, the valve315is also opened. During the subsequent single-axis centrifugation, the washing fluid W is driven out of the washing container301. The opening and closing of the valve315can, for example, be undertaken by a handling unit (robot). Alternatively, it is also conceivable to design the valve315such that it opens automatically by virtue of the centrifugal forces occurring (only) during the single-axis centrifugation.

FIGS. 6aand 6bshow schematically how the washing fluid driven out of the washing container301is collected. In accordance withFIG. 6a, the washing device is fitted with a tub1015for this purpose, which surrounds the rotary plate1003and all the parts of the device arranged on the latter, including the washing container301, and possesses a drain1016.

In the embodiment ofFIG. 6b, a smaller tub1017is provided, which is only arranged around the washing container301. The tub1017can be arranged such that it rotates with the washing container301, or that it is stationary with respect to the angled gear unit1004.

For test washings in the research and development sector, which are concerned, for example, with the examination of the effectiveness of detergents (active wash substances and mixtures of substances) in connection with various textile substrates, it is often desirable that the laundry items after the washing process are present in a fixed or planar form, that is to say not crumpled, or are washed in a fixed or planar state, because by this means the measurements on the laundry items can be executed more simply without any further preparatory measures. This can be achieved with the washing method according to the invention based on dual asymmetric centrifugation without any further effort, since hereby the laundry items do not necessarily have to be moved relative to the washing container. In accordance with an advantageous embodiment of the washing method according to the invention, the laundry items are therefore arranged fixed, in particular planarised, in the washing container, and in the fixed or planarised state are dual asymmetrically centrifuged and washed. For this purpose, a suitable design of the washing container is required.

InFIG. 7a washing container101specially designed for this purpose is schematically represented. Externally, the washing container101once again has an essentially cylindrical form with an axis101aand is divided approximately centrally into two container sections111and112, which for purposes of opening the washing container101are taken apart, and for purposes of closing the washing container are connected with one another in a sealed manner by means of connecting means that are not represented. In the interior of the washing container101, two approximately hemispherical shells113and114are formed, which in between themselves form an essentially spherical washing cell110. The two container sections111and112of the washing container101are of solid design and each has a sealing ring115and116, respectively, on the annular edge surfaces that face each other.

For the execution of the washing method the textile laundry items T are spanned over the annular edge surface of one of the two container sections, in the example represented the upper container section112, and the projecting edge of the laundry items is, for example, by means of an elastic belt117, clamped tightly externally onto the container section112. Then, after filling the lower container section111with washing fluid, the upper container section112is placed onto the lower container section111and the two container sections111and112are connected together in a sealed manner by connecting means that are not represented. The textile laundry items T are then spanned across the washing cell and within the washing cell they are essentially flat, i.e. planar. The washing container101is then subjected to the dual asymmetric centrifugation, as described in connection withFIG. 2, whereby the textile laundry items are washed in a fixed state, here in particular in a planarised i.e. planar, state.

The washing container101ofFIG. 7is additionally fitted with a heating means118, by means of which the temperature of the washing fluid W in the washing cell110can be influenced or adjusted. Depending upon the application, as an alternative to a heating means, a cooling means can also be present. Furthermore, the washing container101can also be fitted both with a heating means and with a cooling means.

In the embodiment schematically represented inFIG. 10, the washing container401having one washing cell410is provided with a thermally insulating jacket450. Before the dual asymmetric centrifugation, the washing fluid in the washing container401is brought up to a desired temperature and held approximately constant during the washing process by the thermal insulation of the washing container401. Once again, sealing rings are designated with415and416, respectively, and an elastic belt is designated with417.

In a further embodiment, the washing container501having one washing cell510, as represented inFIG. 11, is also fitted with an external temperature logger or a suitable temperature probe530, and/or with an internal temperature logger or a suitable temperature probe540. Thus, the profile of the temperature of the washing fluid can be recorded during the washing process. Once again, sealing rings are designated with515and516, respectively, and an elastic belt is designated with517.

For purposes of enhancing the washing effect, an inert granular material G forming washing bodies, for example, glass spheres or beads with a diameter of approximately 2-4 mm, can be introduced into the washing cell10or310of the washing container1or301, respectively, or in principle into each embodiment of the washing container, as is schematically represented inFIG. 1andFIG. 5a.

In the example shown inFIG. 7, the washing cell110of the washing container101is designed in the form of a sphere. The washing cell110can, however, also have another shape, for example an ellipsoidal or a double parabolic shape, etc. Continuously curved, smooth interior walls of the washing cell are in general advantageous with respect to the washing effect that can be achieved. It is advantageous that the washing container is closed. However, it is also possible for the washing process to be executed in an open washing container. By means of the dual asymmetric centrifugation and with reasonably well-adjusted parameters (rotational velocities and quantity of laundry and washing fluid), the mixture of laundry items and washing fluid is automatically held within a defined region by virtue of the centrifugal forces, which, while they are high, they are also acting to some extent in opposition to one another.

The filling level of the washing cell110that is optimal with regard to the washing effect, i.e. the quantity of washing fluid introduced, can be empirically determined in proportion to the shape or volume of the washing cell, and as a function of the rotational velocities about the primary and secondary axes.

In research, a large number of test washing must often be executed, if necessary also under varying conditions, such as, for example, varying washing fluids, temperatures, substrates to be washed, etc. Thereby, for reasons of time, it is desirable if as many test washing as possible can be executed simultaneously. This can be achieved by means of a further advantageous embodiment of the washing method according to the invention, in which a washing container with a plurality of washing cells is deployed.FIGS. 8 and 9show schematically an exemplary embodiment of a suitable washing container with a plurality of washing cells, whereinFIG. 9represents a cross-section along the line IX-IX ofFIG. 8.

The washing container, the whole of which is designated as201, has once again an external form that is essentially cylindrical with an axis201a, and comprises four essentially disk-shaped modules220, which are stacked one above another, and are, or can be, connected with one another in a detachable manner. Each module220has on each, its upper surface and on its lower surface, twelve approximately hemispherical recesses213and214, wherein the recesses of adjacent modules together form a washing cell210in each case. The washing container201thus comprises (in the example shown) a total of 3*12=36 washing cells210, which are arranged in three planes located one above another within the washing container201. The number of washing cells can, of course, be adapted to the particular conditions of use. Thereby, it is important that all washing cells are located in the optimal mixing region of the appropriately deployed dual asymmetric washing device, that is to say, with regard to its axis designs and axis parameters, and/or that all washing cells are arranged around the optimal mixing centre point of the dual asymmetric washing device as deployed.

Each module220has on each, its upper surface and on its lower surface, a sealing ring215and216, respectively, which sealing rings in each case surround all the recesses213and214, respectively. Furthermore, each module220is fitted with a heating means218(and/or a cooling means).

The textile laundry items T are spanned in three separate parts, each between two adjacent modules220, such that they are planar within the individual washing cells210. In this variant of the method, glass beads, or another inert granular material, can also be introduced into the washing cells for purposes of increasing the washing effect.

The same washing fluid can be introduced into all the individual washing cells210of the washing container201. Alternatively, however, different washing fluids can also be used in each washing cell, or in some washing cells. Likewise, the laundry items in the individual washing cells can be the same or different, wherein it is preferable if the laundry items in washing cells arranged in a common plane are in each case the same.

The washing method with a washing container201with a plurality of washing cells210allows the simultaneous execution of (test) washings in series, under different, or also the same, washing conditions.

With regard to the shape of the washing cells210and their filling level, the same considerations apply in a manner corresponding to those stated in connection with the washing container101represented inFIG. 7.

After a dual asymmetric centrifugation, that is to say the actual washing process, has been completed in a manner analogous toFIG. 2, the washing fluid is discharged out of the washing container or out of its washing cell or washing cells. For this purpose, the washing container is preferably centrifuged about a single axis of rotation, whereby the washing fluid is driven through pipes or drainage openings that are not represented, either into one or a plurality of collection cavities within the washing container, or into the centrifuge itself. The pipes or drainage openings must be held closed during the washing process, and may only be opened during the final drainage centrifugation. Alternatively, by means of an appropriate arrangement of the drainage flow pipes or drainage openings, it can also be achieved that no washing fluid is driven out during the dual asymmetric centrifugation, but only during the subsequent single-axis emptying centrifugation.

InFIGS. 12aand 12b, a further embodiment of a washing container is represented. The washing container601with a washing cell610located in its interior is fitted on the lower edge of its base section611with a rotatable closure ring660having several openings661. In the base section611, drainage openings662are arranged, which, in the relative position of the closure ring660shown inFIG. 12, are aligned with the openings661. In this relative position of the closure ring660, the washing container601is open to the external environment. In the relative position of the closure ring660shown inFIG. 12b, the drainage openings662in the base section611are covered by the closure ring660, therefore, the washing container601is closed.

Although the above has only been described and represented in connection with the washing containers201,301and601, drainage openings for purposes of discharging the washing fluid can, needless to say, be installed in all shown embodiments of the washing container.

The invention has been explained with the aid of exemplary embodiments, but shall not to be limited to these exemplary embodiments. Rather, numerous modifications can be conceived by the person skilled in the art, without thereby deviating from the teaching of the invention. The range of protection is therefore defined by the following patent claims.