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Title:
METHOD AND MACHINE WITH ROTATING DRUM FOR THE WASHING OR DYEING TREATMENT OF TEXTILE ARTICLES
Document Type and Number:
WIPO Patent Application WO/2004/055252
Kind Code:
A1
Abstract:
The present invention relates to a method for the washing or dyeing treatment of textile articles (7) in a machine (1) with rotating drum (6), as well as to a machine suitable for implementing in particular this method. The method is characterized in that said treatment is performed by immersing and extracting said textile articles (7) in/from said bath (B) in accordance with treatment cycles (C1; C2) which envisage rotation of said drum (6) during which said textile articles (7) are kept in contact with the side surface (9) of said drum (6) by the centrifugal force imparted to them by the speed of rotation of said drum (6). The method is also characterized in that the ratio between centrifugal acceleration of said drum (6) and the acceleration of gravity is equal to a compensation value n=ac/g in the range 1.1 to 4. and in that the treatment cycles (C1; C2) are distinguished by a tangential velocity of said drum (6) in the range of between 2.5 and 4.5 m/s. the machine (1) with rotating drum (6), in particular suitable for implementing the method according of through-holes (8) formed in the side surface (9) of is characterized in that said drum is able to rotate with a ratio between the centrifugal acceleration and the acceleration of gravity equal to a compensation value n=ac/g in the range of 1.1 to 4 and in that said tangential velocity of said drum (6) is in the range of 2. 5 to 4.5 m/s.

Inventors:
TONELLO OSVALDO (IT)
Application Number:
PCT/IT2003/000832
Publication Date:
July 01, 2004
Filing Date:
December 18, 2003
Export Citation:
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Assignee:
TONELLO S R L (IT)
TONELLO OSVALDO (IT)
International Classes:
D06B3/30; D06F35/00; (IPC1-7): D06F35/00
Foreign References:
EP0404047A11990-12-27
DE4310595A11994-10-06
DE3805803A11989-03-09
Other References:
PATENT ABSTRACTS OF JAPAN vol. 2000, no. 05 14 September 2000 (2000-09-14)
PATENT ABSTRACTS OF JAPAN vol. 2000, no. 18 5 June 2001 (2001-06-05)
Attorney, Agent or Firm:
Gallo, Luca (Via Berchet 9, Padova, IT)
Download PDF:
Claims:
CLAIMS
1. 1) Method for the washing or dyeing treatment of textile articles (7) in a machine (1) with rotating drum (6), comprising the following operations: introducing said textile articles (7) into said drum (6); causing rotation of said drum (6) with said textile articles (7) inside a bath (B) containing in solution form washing or dyeing products for performing said treatment; discharging said bath (B) after a predetermined period of time, characterized in that said treatment is performed by immersing and extracting said textile articles (7) in/from said bath (B) in accordance with treatment cycles (Cl ; C2) which envisage rotation of said drum (6) during which said textile articles (7) are kept in contact with the side surface (9) of said drum (6) by the centrifugal force imparted to them by the speed of rotation of said drum (6).
2. Method according to Claim 1, characterized in that the ratio between centrifugal acceleration of said drum (6), namely of said articles, and the acceleration of gravity is equal to a compensation value n=ac/g in the range of 1.1 to 4.
3. Method according to Claim 1 or 2, characterized in that said treatment is performed by immersing and extracting said textile articles (7) in/from said bath (B) in accordance with treatment cycles (C1 ; C2) distinguished by a tangential velocity of said drum (6) in the range of between 2.5 and 4.5 m/s.
4. Method according to any one of the preceding claims, characterized in that said treatment cycle (C1) envisages reversals in the direction of rotation of said drum (6) with a pause (tp) between one rotation (O) and the next (A), during which the textile articles (7) adhering to said drum (6) and situated above said bath (B) fall as a result of gravity into said bath (B).
5. Method according to any one of the preceding claims, characterized in that said treatment cycle (C2) envisages the rotation of said rotating drum (6) always in the same direction with repeated deceleration of the speed of rotation from a maximum value (Nmax) to a minimum value (Nmin).
6. Method according to Claim 5, characterized in that said textile articles (7) remain in contact with the side surface (9) of said drum (6) for the whole of the treatment time.
7. Method according to any one of Claims 1 to 5, characterized in that each of said treatment cycles (C1 ; C2) has a startup time (ta ; t'a) of short duration.
8. Machine (1) with rotating drum (6), in particular suitable for implementing the method according to one or more of the preceding claims, comprising: a frame (2) provided with resilient means (4,5) which support a tank (3) inside which a treatment bath (B) is contained ; a rotating drum (6) intended to receive textile articles (7), housed inside said tank (3) and having a plurality of throughholes (8) formed in the side surface (9) of said drum; means (10) for supporting and rotating said drum (6), connected to drive means, characterized in that said drum is able to rotate with a ratio between the centrifugal acceleration and the acceleration of gravity equal to a compensation value n=aC/g in the range of 1.1 to 4.
9. Machine (1) according to Claim 8, characterized in that the tangential velocity of said drum (6) is in the range of between 2.5 and 4.5 m/s.
10. Machine (1) according to Claim 9, characterized in that said drum (6) is distinguished by a diameter in one of the following ranges: 1.7 to 1.9 m; 1.5 to 1.7 m; 1.2 to 1.5 m; 0.8 to 1.0 m and correspondingly is provided with a tangential velocity in the following ranges: 3.0 to 4.5 m/s; 3.0 to 4.5 m/s; 2.8 to 4.5 ; 2.8 to 3.8 m/s.
11. Machine (1) with rotating drum (6), in particular suitable for implementing the method according to one or more of Claims 1 to 7, comprising: a frame (2) provided with resilient means (4,5) which support a tank (3) inside which a treatment bath (B) is contained; a rotating drum (6) intended to receive textile articles (7), housed inside said tank (3) and having a plurality of throughholes (8) formed in the side surface (9) of said drum; means (10) for supporting and rotating said drum (6), connected to drive means, characterized in that the bottom (18) of said tank (3) is provided with flow breaking means (11) able to oppose the rotational entrainment of said treatment bath (B).
12. Machine (1) according to Claim 11, characterized in that said flowbreaking means (11) consist of a lowered zone (12) formed in the said bottom (18) of said tank (3).
13. Machine (1) according to Claim 11, characterized in that said drum (6) has one or more inwardly projecting longitudinal vanes (13) for moving said textile articles (7).
14. Machine (1) according to Claim 12, characterized in that said lowered zone (12) has an inclined base (14) converging towards an opening for attaching a discharge pipe (15).
Description:
"METHOD AND MACHINE WITH ROTATING DRUM FOR THE WASHING OR DYEING TREATMENT OF TEXTILE ARTICLES" DESCRIPTION The invention relates to a method for the washing or dyeing treatment of textile articles and to a machine with rotating drum for implementing this method.

It is known that, in the industrial sector, the washing or dyeing treatment of textile articles is normally performed using rotating-drum machines. These machines essentially consist of a frame which supports a tank inside which a drum is rotated by suitable drive means, said drum receiving the textile articles to undergo the washing or dyeing treatment.

The rotating drum has a plurality of through-holes through which the treatment bath contained in the tank flows.

Moreover, the rotating drum usually has inwardly directed longitudinal vanes which keep the textile articles in movement while the drum rotates. In rotating-drum machines of the known type, therefore, the washing or dyeing of the garments is performed during rotation of the drum by the action of the longitudinal vanes which lift the textile articles above the treatment bath and release them once they reach the top part of the rotating drum so that they fall by means of gravity into

the treatment bath.

The rotating-drum washing or dyeing machines of the known type mentioned above have the drawback that the mechanical action exerted on the textile articles by the impact against the bath during falling causes wear of the garments, in some cases to an unacceptable degree.

A further drawback consists in the fact that, in order to perform effective treatment of the articles, it is necessary to adopt during operation bath ratios (understood as meaning the ratio between the weight of the textile articles and the weight of the treatment bath) which are fairly high, i. e. of about 1: 10 to 1: 30.

These drawbacks have been overcome by means of a rotating-drum machine-forming the subject of Italian patent No. VI96A000142 filed in the name of the same Applicant of the present invention-which performs the dyeing or washing treatment by immersing the textile articles in the bath while they are kept in contact with the side surface of the rotating drum by the centrifugal force and spraying them with the treatment bath when they emerge again from the bath during rotation of the drum.

Essentially the treatment is performed by combining the spraying action with immersion of the garments in the treatment bath, while the garments remain constantly in contact with the rotating drum.

This method eliminates falling of the garments into the bath, with the advantage of reducing considerably the degree of wear to which they are subject.

By adopting this procedure, it is also possible to reduce the bath ratios since, with the garments being distributed over the whole surface of the rotating drum, the number of them immersed per unit of time inside the bath is less than in the known art.

It is therefore possible to employ during operation bath ratios which reach values of 1: 5 or less.

In addition to this, the high speed of rotation of the drum, which is decidedly greater than that used in the known art, increases the frequency of immersion and extraction of the garments into/from the bath per unit of time, improving the quality of the treatment.

The treatment performed in accordance with the teachings of the abovementioned patent nevertheless has a series of drawbacks.

A first drawback consists in the fact that the bath which is sprayed encounters a varied resistance in the zones of the articles making contact with the side surface of the rotating drum where there are no holes and the zones of the articles positioned opposite the holes in the side surface of the rotating drum. In fact in the first case there is a greater tendency to retain the bath

and this results in a non-uniform finish of the garment at the end of treatment.

This drawback is made worse by the fact that the garments, during treatment, remain in contact with the rotating drum always in the same position.

Another drawback consists in the fact that the presence of ducts for conveying and recirculating the bath to the spraying devices results in use of part of the overall dyeing bath, a larger quantity of which must therefore be used compared to that strictly necessary.

Therefore, immersion of the garments, in accordance with this solution of the known type, is practically absent and cleaning or dyeing thereof is essentially performed by the spraying action alone, as claimed in the said patent.

A further drawback which may be encountered in the solution contained in the patent No. VI96A000142 is that of not defining in a sufficiently precise manner the peripheral speed of the rotating drum.

The sole reference to the speed is that regarding the speed of rotation, which is considered to be slightly lower than the centrifuging speed which is used for wringing.

Last but not least, another drawback consists in the fact that some times the suction pump connected to the

recirculating ducts supplies the spraying devices in an irregular manner and this constitutes a further factor which adversely affects the quality of treatment.

The present invention proposes overcoming the abovementioned drawbacks.

In particular the main object of the present invention is to provide a method for washing or dyeing textile articles in a machine with rotating drum which is able to achieve a better quality of the finished product compared to the methods of the known art.

Another object is that the method according to the invention should be able to achieve a further reduction in the values of the bath ratios compared to those of the known art.

A further object is to reduce the cost of manufacturing rotating-drum machines.

Said objects are achieved by a method for the washing or dyeing treatment of textile articles in a machine with rotating drum, which, in accordance with the contents of the first claim, comprises the following operations: - introducing said textile articles into said drum; - causing rotation of said drum with said textile articles inside a bath containing in solution form washing or dyeing products for performing said treatment;

- discharging said bath after a predetermined period of time; and is characterized in that said treatment is performed by immersing and extracting said textile article in/from said bath in accordance with treatment cycles which envisage rotation of said drum during which said textile articles are kept in contact with the side surface of said drum by the centrifugal force imparted to them by rotation of said drum.

According to a preferred mode of application of the method of the invention, the treatment cycle envisages reversals in the direction of rotation of the drum with a pause between one rotation and the next during which the textile articles adhering to the drum and situated above the bath fall as a result of gravity into the said bath.

According to a further applicational variant, the rotation of the drum is performed always in the same direction, with periodic variations from a maximum value to a minimum value of the speed of rotation of the drum, while keeping the garments always in contact with the side surface of the drum for the whole of the treatment time.

The rotating-drum machine which implements the method according to the invention comprises: - a frame provided with resilient means which

support a tank inside which said treatment bath is contained; - a rotating drum inside which said textile articles are introduced, said drum being housed inside said tank and having a plurality of through-holes formed in said side surface; - means for supporting and rotating said drum, connected to drive means; and is characterized in that the bottom of said tank is provided with flow-breaking means able to oppose the rotational entrainment of said treatment bath.

Advantageously, the method according to the invention allows the washing or dyeing treatment of the textile articles to be performed more efficiently, employing bath ratios even lower than those required by machines which envisage spraying of the bath.

In an equally advantageous manner, the method according to the invention allows a reduction in the wear to which the garments are subject during treatment, improving the quality of the final product.

Even more advantageously, the rotating-drum machine according to the invention has a cost which is lower than that of equivalent rotating-drum machines nowadays commercially available.

Said objects and advantages will be indicated more

clearly during the description of preferred embodiments of the invention which are provided by way of a non- limiting example with reference to the accompanying plates of drawings in which: - Fig. 1 shows a longitudinal section through the rotating-drum machine, also forming the subject of the invention, which implements the method according to the invention; - Fig. 2 shows a cross-section along the plane II-II of the machine shown in Fig. 1; - Fig. 3 illustrates, in the form of a velocity/time diagram, a treatment cycle of the method according to the invention; - Fig. 4 illustrates, in the form of a velocity/time diagram, another treatment cycle of the method according to the invention.

The rotating-drum machine which is used to implement the method according to the invention is shown in Figures 1 and 2, where it is denoted overall by 1 and where the rotating drum associated with it is denoted by 6.

The method according to the invention envisages introducing the textile articles, denoted overall by 7, into the drum 6, causing rotation of the drum 6 with the textile articles 7 inside a bath B containing in solution form washing or dyeing products for performing the

treatment, and then discharging the bath B after a predetermined period of time.

According to the invention, this washing or dyeing treatment is performed by immersing and extracting the textile articles 7 into/from the bath B in accordance with treatment cycles which envisage rotation of the drum 6 during which the textile articles 7 are kept in contact with the side surface 9 of the drum 6 by the centrifugal force imparted to them by the rotation of the drum 6.

More particularly, this treatment is performed with a ratio between the centrifugal acceleration acting on the articles or on the side surface of the drum and the acceleration of gravity equal to a compensation value n=aC/g within the range of 1.1-4.

In greater detail, if v indicates the tangential velocity of the drum, D the angular velocity of the drum, r the radius of the drum, d the diameter of the drum, ac the centrifugal acceleration of the drum, g the acceleration of gravity, and n the abovementioned compensation ratio equal to n= ac/g, as is known, the following physical relations exist: v=Dr ; aC=22r=v2/r.

According to the invention, the articles are made to adhere by the centrifugal force to the internal surface of the drum with the correct compression avoiding wear of the articles against the said surface, in particular

avoiding the formation of different treatment zones opposite the holes in the drum and the smooth parts. The said centrifugal force is able to ensure that the articles have a sufficient degree of softness or looseness or on the other hand an optimum compaction in order to allow correct penetration of the liquid cleaning or dyeing product.

It should be noted that this acceleration has been designed to achieve an optimum rate of penetration of the liquid, which must not be excessively high, in order to avoid damaging the garments, creating for example the unattractive napped effect, and must not be too low, in order to avoid the liquid not penetrating correctly throughout the fibre of the articles.

The tangential velocity of the drum 6 during the abovementioned treatment cycles for achieving optimum penetration of the product into the articles, as explained above, advantageously assumes values in the range of between 2.5 and 4.5 m/s.

Moreover, the abovementioned velocity, taking into account the dimensions of the drums, is related to the corresponding acceleration values so as not to produce either falling of the articles, with their consequent mechanical wear, or excessive compaction, which is also responsible for damage to the articles.

According to the preferred mode of application of the method according to the invention, described here, the treatment cycle C1, shown in the diagram of Fig. 3, envisages a pause tp between one rotation and the next, during which the textile articles 7 adhering to the drum 6 and situated above the bath B fall owing to the force of gravity into the said bath B.

The rotation of the drum 6 is performed, preferably, but not necessarily, in clockwise directions O and anti- clockwise directions A, which are separated by a pause tp of short duration, during which the drum 6 is at a standstill.

It should be noted that, for each rotation, there is also a start-up time ta, also of short duration, for bringing the drum 6 to the programmed rotation condition N in which it remains for a time period to before reversal in the direction of rotation.

Obviously the number of revolutions N for rotation and the time intervals are chosen by the user.

Stoppage of the drum 6 causes the textile articles to fall as a result of gravity into the bath B since there is not sufficient centrifugal force to keep them in contact with the side surface 9 of the drum 6.

This allows the articles to modify their position when rotation resumes in the opposite direction,

favouring homogenization of the treatment over the entire surface of the garments.

A variation in the treatment cycle consists of the cycle C2, shown in Fig. 4, which differs from that in Fig. 3 owing to the fact that it envisages the rotation of the rotating drum 6 always in the same direction (clockwise or anticlockwise) with cyclical and continuous decelerations from a maximum speed NmaX to a minimum speed Nmin.

These speeds must nevertheless be such as to keep the textile articles always in contact with the rotating drum.

In this way the garments being treated are subject to a continuous compressing and expanding action which reproduces substantially the working conditions which are obtained with washing by hand.

The machine 1 with rotating drum 1 which implements the method according to the invention and itself forms the subject of the invention comprises, in addition to the rotating drum 6 inside which the textile articles 7 are introduced, a frame 2 provided with first resilient means 4 and second resilient means 5 which support a tank 3 inside which the treatment bath B is contained.

The rotating drum 6 is housed inside the tank 3 and has a plurality of through-holes-indicated overall by 8

- formed and distributed uniformly over its side surface 9.

The machine 1 according to the invention also comprises supporting and rotating means, denoted overall by 10 and consisting of a shaft 16 fixed by means of screws 17 to the rotating drum 6 and connected to drive means, not shown in the accompanying figures, which cause rotation of the drum 6.

According to the invention, the bottom 18 of the tank 3 is provided with flow-breaking means, which are denoted overall by 11 and are designed to oppose the rotational entrainment of the treatment bath B and in this way produce swirling and atomization of the treatment liquid such as to allow the latter to treat the articles by penetrating correctly into their fibres.

For this purpose, according to the invention the articles are subject to optimum conditions with the drum 6 which rotates during treatment so as to produce a ratio between the centrifugal acceleration and the acceleration of gravity equal to a compensation value of n=ac/g in the range of 1.1 to 4, as specified in the description relating to the method of treatment.

In greater detail, the tangential velocity of the drum 6 during the treatment is in the range of between 2.5 and 4.5 m/s.

Advantageously, optimum tangential velocities in the ranges of 3.0 to 4.5 m/s, 3.0 to 4.5 m/s, 2.8 to 4.5, 2.5 to 3.8 m/s, respectively, for drums 6 distinguished by diameters in the ranges of 1.7 to 1.9 m, 1.5 to 1.7 m, 1.2 to 1.5 m and 0.8 to 1.0 m have been recorded.

The table shows below the drum values for five preferred embodiments of machines, relating to the diameter, the angular velocity, the compensation ratio and the tangential velocity which have proved to be particularly advantageous for optimum treatment of the garments, under the conditions specified above: D [m] D [revs/minute] N V [m/s] 1.8 40 1.61 3.77 1.6 45 1.81 3.77 1.3 50 1.81 3.40 1.3 55 2.20 3.74 0.9 70 2.47 3.30

According to the preferred embodiment described here, the flow-breaking means 11 consist of a lowered zone 12 formed in the bottom 18 of the tank 8 and provided with an inclined base 14 converging towards a pipe 15 for discharging the bath B.

In Figures 1 and 2 it can be seen moreover that the rotating drum 6 has, preferably but not necessarily,

three inwardly projecting longitudinal vanes, each denoted by 13, for moving the textile articles 7.

Operationally speaking, after introducing the articles to be treated into the rotating drum 6 and the treatment bath B into the tank 3, the treatment is started by causing rotation of the rotating drum 6 in accordance with any one of the cycles C1, C2 or another cycle chosen by the user.

During treatment, the textile articles 7, which are kept in contact with the rotating drum 6 by the centrifugal force, pass through the bath B present in the bottom 18 of the tank 3, being exposed to treatment.

During rotation, the rotating drum 6 would tend to cause rotation of the bath B, this being opposed instead by the lowered zone 12 which stops it, producing atomization of the bath B which advantageously assists treatment of the textile articles 7 when they are in the position extracted from the bath B.

The longitudinal vanes 13 allow easier movement of the textile articles 7, in particular during raising of the latter from the bath B.

The washing or dyeing treatment may be performed with bath ratios which are lower than those of machines of the known type and for treatment of the same quantities of product.

Moreover, it also possible to achieve the object of improving the final quality of the textile articles, in terms of more uniform distribution of treatment and lesser wear.

On the basis of that stated above it can be understood therefore that the method according to the invention and the machine which implements it achieve the objects and obtain the advantages listed above.

During realization, modifications may be made both to the method of the invention and to the rotating-drum machine which implements it.

Thus, for example, the treatment cycles may be varied according to the user's requirements, while the machine may undergo modifications aimed at improving the treatment of the products or simplifying its construction.

As regards moreover the machine, the lowered zone formed on the bottom of the tank could have any form and dimensions different from those shown in the figures below.

All the variants mentioned and not shown in the accompanying illustrative plates, should they fall within the scope of the claims which follow, must be regarded as protected by the present patent.