Abstract:
A textile washing machine has a rotary basket balanced in at least one of its two planes, where optionally a first balance ring is structurally formed at the lower part of the basket or bottom of basket in order to balance the lower plane of the rotary basket and/or optionally, a second balance ring structured at the upper part of the basket. The first balance ring comprises: a channel or track that forms an integral part with the bottom of basket, a viscous drag fluid lodged in the track, a plurality of spheres lodged in the channel or track, immerse in the viscous drag fluid, and a lid that seals hermetically against the track. The lid comprises at least one radial rib in order to provide the bottom of basket with a structural reinforcement so that the bottom of basket does not weaken due to the presence of the track or channel. The second balance ring includes: a base with a first wall and a second wall, a cover that closes the base and with the same walls of the base, a working fluid lodged in the base, at least a curved blade lodged in the base where the blade covers from the first wall of the base and leaves a clearing between the blade and second wall, allowing the working fluid to have a vertical component; and at least a straight blade lodged in the base and alternated with the at least one aforementioned curved blade.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims priority from Mexican application Serial No. MX/a/2009/002329 filed Feb. 27, 2009, which is incorporated herein by reference in its entirety. 
       FIELD OF THE INVENTION 
       [0002]    The present invention relates to washing machines, and more specifically, to washing machines that balance the load in a rotating centrifuge basket, where the balance system comprises balance rings in two planes. 
       DESCRIPTION OF THE RELATED ART 
       [0003]    Any person who uses or has used a washing machine has had the opportunity to experience at times that the machine, when in spinning-dry (centrifuge) or in clothes dehydration process, produces extreme vibration, sometimes even making the machine move from its original place. This is known colloquially as “walking”. This occurs mainly because somehow the clothes and objects to be washed are not uniform, they have different shapes and their materials have different densities, and once the process of washing has finished and having drained the washing basket, most of the clothes are deposited and remain at one point of the mentioned basket. This makes and keeps the basket unbalanced. 
         [0004]    This problem also occurs when big and heavy objects are introduced into the washing basket, like for example shoes. So when the washing process has finished and having drained the wash liquor from the basket, the shoes are deposited at the bottom of the basket producing great imbalance in the basket and hence generating undesired strain in the washing machine components such as, for example, excessive noise, severe vibration and frequent walking of the washing machine. On the other hand, the dynamic loads originated by the excessive vibration generate wear and damage of the washing machine components. 
         [0005]    Due to the reasons just mentioned and others that a technician in the matter could discern, the centrifuge forces resulting from the objects in the washing basket need to be balanced. 
         [0006]    Several efforts have been made concerning the solution of this problem. The prior art indicates that the use of the balance rings, which are hollow rings that are placed at the top of the washing basket; can be used as counterweight for the load of clothes because the interior part of the ring or toroid contains some liquid, solid balls or elements that contribute with mass. These elements can be made of steel slag or ceramics, and they adopt a position contrary to the centrifuge forces created by the position adopted by the objects to be washed, and so balancing the washtub. 
         [0007]    For example, the document Hayashi&#39;s U.S. Pat. No. 4,044,026 et al, describes a balance ring placed at the top of a washing basket, which contains liquid solution in its interior, as well as a series of partitions that keep the liquid in chambers once the process of dehydration of objects to be washed by centrifugal action has initialized. The fact of having rotating blades in the partitions, where the liquid is kept separately while the washing basket is spinning in centrifugal mode, has the disadvantage of an undesired vibration during the system&#39;s transitional stage. Plus it does not allow the use of high velocity centrifuge, which is important when it comes to dehydrating more and consuming less time. 
         [0008]    We can find another example of balance rings in document Do Weon Kim U.S. Pat. No. 5,782,110, which describes a balance ring that is prostrated on the washing basket, which in its interior has 3 tracks at different radius and with different widths of track, in which steel balls coated with oil are lodged. The diameter of the steel balls is in accordance with the width of the track in which they are placed, and so there are 3 different diameters of steel balls, which tend to be larger towards the outside. Once in the centrifugal stage, these steel balls counteract the loads that are imbalanced, giving balance to the washing basket when spinning. Even though the inventor of the document being discussed claims that his invention allows the spinning of the washing basket at high velocities, the construction of the mentioned balance ring is quite complicated, with too many parts involved, needs special fluid, is difficult to assemble and hence is expensive. 
         [0009]    This is why the majority of solutions to this imbalance problem in a washing basket fall upon putting a crown on the wash basket with a balance toroidal ring, which solves the problem to a large extent. However, it is somehow obvious that an upper balance ring together with a lower one works better; that is to say, that by preferably placing a balance ring at the upper part of the basket, adding another balance ring at the lower part, helps to achieve a transitional state of vibration that is gentler and better controlled, together with the possibility of obtaining high velocity centrifuge, helping in what concerns efficiency of both the washing machine and the subsequent process of drying. 
         [0010]    To wit that, when having high velocity centrifuge, this makes it possible to lessen the time the operation consumes when exerting stronger centrifugal force on the items placed in the washing basket, which results in the wash liquor mass being expelled faster towards the vertical wall in the washing basket, consequently, obtaining a dehydration of the items in the washing basket in less time, which results in an obvious saving of energy when using the washing machine. The following process, which is drying the clothes, also benefits with a higher velocity centrifuge because the clothes are already more dehydrated before beginning the drying process. 
         [0011]    Several efforts have been directed in order to achieve these results that are highlighted in patent Jin Soo Kim U.S. Pat. No. 5,802,885, where a couple of disks are adapted, one for each extreme of the washing cylinder. These disks together with trays help contain the plurality of tracks on which several spheres will be running, which makes this design quite complicated because it contains many parts that need to be assembled, which makes it difficult to manufacture. Besides, the tracks&#39; seal need maintenance, to with that the spheres have to be submerged in some kind of liquid, or if not, at least the tracks need to have a high friction coefficient. 
         [0012]    Another example of this technique in patent Do Weon Kim et al. U.S. Pat. No. 5,761,933, describes a washing basket that is crowned on both upper and lower extremes, with a balance ring with liquid saline solution in its interior. The lower balance ring can be completely coupled with the lower part of the basket, having several chambers with an axis of symmetry that describes a concentric circumference to the basket where each chamber has a specific width in order to lodge different sizes of spheres. This assembly which is done at the lower part of the mentioned basket makes it extremely complicated and difficult to manufacture. Namely that, the sealing of each chamber has to be very well done and taken care of, because having several chambers, the probabilities of liquid leaks are higher, hence strict controls are required, as well as very strict manufacturing tolerances, which entails a manufacturing cost. 
         [0013]    This is why one of the objectives of the present invention is to provide a system of balance rings in two planes, that do not require the use of an expensive fluid, that are easy to construct, that allow the reduction of the vibration generated in the transitional stage, a system that operates at high speeds, being it possible to adapt it to different types of wash baskets in washing machines with a vertical axis preferably, without having to exclude those with a horizontal axis, with a reduced number of parts, easy to assemble and manufacture, at low maintenance costs and reliable, among other characteristics. 
       BRIEF SUMMARY OF THE INVENTION 
       [0014]    The present invention relates to the field of washing machines, preferably automatic washing machines with a vertical or horizontal axis and machines that have in common that they have a basket with drilled holes, that spins around a rotation axis, propelled usually by an electric motor that can be coupled directly or using some mechanism for energy transmission, the most common being bands and pulleys, gear boxes, etc. 
         [0015]    The mentioned washing machines, whether with horizontal or vertical axis undergo imbalance, caused to a large extent by the arrangement of the deposited objects within the washing basket or drum, objects which at their dehydrating stage have to spin at high velocities in order to force the water or washing liquor contained in the objects that are in the basket, to go towards the walls of the basket that have drilled holes, by action of the centrifugal force to which the mentioned objects are submitted, and so the washing liquor is then collected in the exterior tub so that it can be extracted with a pump towards the drainage. 
         [0016]    Usually, the baskets are crowned with balance rings at only one of the extremes, which functioned correctly in the past, when the energy consumption requirements were not so strict, and when it was not necessary for the objects in the washing basket to spin at high velocities when at the stage of dehydration. This, without mentioning that the washing machines are manufactured at present with materials that are lighter, together with the technological advances in engineering, which leads to no longer requiring security factors as broad in order to make the pieces sturdy, hence heavy. And so, being the washing machines lighter, the vibration caused by imbalance becomes a major issue to deal with when considering the performance of the machine. To wit that, if the imbalance force is such, the washing machine will tend to “walk” or “dance”, which are undesirable conditions for the machine&#39;s adequate performance. 
         [0017]    In this manner, the present invention suggests crowning both extremes of the basket with balance rings, placing at the opened extreme of the basket a balance ring with blades or chambers that works mainly with a fluid that can be calcium chloride or sodium chloride among others, same case as described in the application MX/a/2007/016516 for a hydrodynamic balance ring for a centrifugal rotation machine, from Ortega Breña et al. 
         [0018]    Besides placing the ring at the other extreme of the washing basket, another ring is placed integrally at the exterior face of the disk or bottom of the basket, a balance ring with spheres made preferably of steel, of which weight, size and amount have been carefully selected, helping to simplify their manufacture, reducing the number of parts required and hence making it less costly and more reliable. The spheres run submerged in a fluid that has a specific viscosity; the fluid&#39;s specific function is to slither the spheres in transitional state so that they don&#39;t slip within the track and they reach the position contrary to the imbalanced load in a quicker manner. This also helps to mitigate the noise generated by the spheres by not allowing them to get to a standstill or “stop dead”; besides which the mentioned fluid absorbs the energy generated by the pile-up collision, plus the same fluid also has a weight that contributes to balance the magnitude of the vector resulting from forces. 
         [0019]    Having two balance rings allows balancing the washing basket in two different planes, giving vectors that result in both planes, and these counteract the resulting magnitude of the imbalance vector, which is always variable in these planes. This helps the basket to balance itself in a short period of time, considerably reducing the force transmitted into the suspension system and from it into the cabinet, making it less probable that the washing machine “dances” or “walks”, in view of the fact that washing machines weigh less at present. 
         [0020]    Balancing correctly and opportunely the objects distributed in a non uniform manner in the basket, which causes a considerable magnitude vector of imbalance, is desirable. To wit that, otherwise, some kind of mass or burden would have to be placed in the washing machine or the existing ones would have to be heavier, in order to avoid the “walking” or “dancing” phenomenon of the washing machine. 
         [0021]    The balance ring containing balls placed at the exterior part of the disk or bottom of the basket has been thought to be completely adaptable to it, to wit that the track through which the spheres will be running is part belonging to the basket itself. This means, depending on the design of the basket, its bottom or disk, which preferably should result from a polymer injection process, contains within its intrinsic structure the mentioned track, being this part removed from the mold with the geometry of the track included, giving the washing basket a simplified yet sturdy bottom or disk. Namely that, the design has been such that the placing of the track at the exterior face of the bottom or disk of the washing baskets has a very good rigidity, giving flexibility in the assembly line, this is, the same basket, bottom or disk of basket can be used in washing machine designs for which due to factors concerning the company&#39;s decisions, costs or other marketing issues, they choose not to place a balance ring with spheres at the bottom or disk of the washing basket. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0022]    The particular characteristics and advantages of this invention, as well as other objects of the invention, will become apparent in the following description, given with the attached figures, which are: 
           [0023]      FIG. 1  is a front cross-section of a washing machine. 
           [0024]      FIG. 2  is a representative sketch of the imbalance phenomenon of the basket. 
           [0025]      FIG. 3  is a second representative sketch of the imbalance phenomenon of the basket. 
           [0026]      FIG. 4  is a third representative sketch of the imbalance phenomenon of the basket. 
           [0027]      FIG. 5  is a front cross-section of a sub-washing machine in a representative sketch of imbalance forces of the basket. 
           [0028]      FIG. 6  is an upper view of a balance ring containing liquid. 
           [0029]      FIG. 7  is an upper view of a balance ring containing spheres. 
           [0030]      FIG. 8  is a conventional exploded perspective view of a balance ring in the present invention. 
           [0031]      FIG. 9  is a cross-section of a balance ring in the prior art. 
           [0032]      FIG. 10  is a phantom conventional perspective of the internal geometry of a positive curved blade. 
           [0033]      FIG. 11  is a cross-section of a balance ring in the present invention. 
           [0034]      FIG. 12  is a cross-section of the parts of the balance ring in the present invention. 
           [0035]      FIG. 13  is a cross-section phantom view of the balance ring in this invention. 
           [0036]      FIG. 14  is a cross-section phantom view of the balance ring in this invention. 
           [0037]      FIG. 15  is a cross-section conventional perspective in phantom view of the parts of the balance ring in the present invention. 
           [0038]      FIG. 16  is a cross-section conventional perspective in phantom view of part of the balance ring in the present invention. 
           [0039]      FIG. 17  is a cross-section of the front phantom view of part of the balance ring in the present invention. 
           [0040]      FIG. 18  is a cross-section of the upper view of part of the balance ring in the present invention. 
           [0041]      FIG. 19  is a cross-section of the upper view of part of the balance ring in the present invention. 
           [0042]      FIG. 20  is a Bode plot comparing the basket&#39;s angular velocity in RPM versus the peak-to-peak vibration in the washing machine&#39;s cabinet. 
           [0043]      FIG. 21  is a second Bode plot comparing the basket&#39;s angular velocity in RPM versus the peak-to-peak vibration in the washing machine&#39;s cabinet. 
           [0044]      FIG. 22  is a front view of the basket in the present invention with the balance rings placed in the different planes. 
           [0045]      FIG. 23  is an exploded conventional perspective view of the bottom of the basket. 
           [0046]      FIG. 24  is an upper view of the spheres. 
           [0047]      FIG. 25  is a conventional perspective of an upper view of the bottom of the basket. 
           [0048]      FIG. 26  is a bottom conventional perspective view of the bottom of the basket. 
           [0049]      FIG. 27  is a conventional perspective view of the lid of the inferior balance ring. 
           [0050]      FIG. 28  is an upper view of the lid of the inferior balance ring. 
           [0051]      FIG. 29  is a conventional perspective view of the bottom of the basket. 
           [0052]      FIG. 30  is a comparative diagram between the balance forces, taking the number of existing balls into account. 
           [0053]      FIG. 31  is a diagram of the imbalance forces in view of the number of balls. 
           [0054]      FIG. 32  is a third Bode plot comparing the angular velocity of the basket in RPM versus the peak-to-peak vibration in the washing machine&#39;s basket. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Theoretical Approach 
       [0055]    The imbalance in a rotor can occur due to various causes, one of them can be due to the rotor&#39;s manufacturing method, having set more material in a specific point of the rotor, or on the contrary, due to a lack of uniformity in the density of the material. Sometimes, it may occur that other phenomena can cause the undesired vibrating effects in the washing machines, such as a deficient alignment of its shafts, defective bearings, inadequate lubrication of the bearings or supporting points that cause friction, mechanical looseness, and a deficient alignment of the bands with the pulleys, etc. The most interesting cause for purposes of the present invention is the imbalance due to the internal loads in the rotor. As can be deducted from  FIG. 1 , a washing basket  12  of a sub-washing machine  17  is set up within a tub  13 . This basket  12  is moved or driven by a shaft  14  which is rigidly coupled with the bottom part of the basket  12 , usually by means of a central part or link called hub  16 . The shaft  14  can be coupled directly with a motor or induced pulley; in the case shown in  FIG. 1  aforementioned, the shaft  14  is coupled with a planetary reduction gearbox  53 , which at the same time obtains energy coming from an induced pulley  50  that obtains energy through a tread (not shown) that is energized by an electric motor  54 . The basket  12  is composed in its lower part of a bottom of basket  58  which has a similar geometry to that of a disk, and which contains the hub  16 , in order to spin in unison with it; the basket  12  also has a cylindrical wall that is crowned with the upper balance ring  10 . The tub  13 , in its lower part, has some supports that support the shock absorbers  18 , from which rods  19  emanate. 
         [0056]    The bottom of the basket  58 , in its exterior face has a channel or track  57 , which contains some spheres  59 , as well as a drag fluid  60 . In order to keep the spheres  59  and the drag fluid  60  inside, it is necessary to use a lid  64 , that somewhere in its surface has a small hole  70  where the drag fluid  60  is introduced, and such hole  70  is sealed with a stopper  65 . This lid  64  is specially designed to provide structural reinforcement to the bottom of the basket  58 , because it is evident that when integrating the track  57  into the bottom of the basket  58 , the result is a structural weakening of the component due to the interruption of the radial reinforcements  72 , so consequently the design of the lid  64  requires special attention in order to avoid a reduced capacity of the bottom of the basket  58  to support the load of clothes and the efforts induced by the rotation. And so, the lid  64  is designed with such a geometry that its construction comprises a series of radial ribs  71  that give continuity to the radial reinforcements  72  of the bottom of the basket  58 , hence achieving that with the assembly of lid  64  with the bottom of basket  58  a mechanical resistance equal or superior to the one present at the bottom of the basket  58  without the track  57  and with the continuous radial reinforcements  72  is obtained. 
         [0057]      FIGS. 2 ,  3  and  4  help us understand the imbalance phenomenon in rotors, considering the basket  12  as a hollow rotor, in which in its interior all kinds of objects are deposited that adopt a random position in the interior of the mentioned hollow rotor. Having explained things,  FIG. 2  illustrates a rotor or basket  12  which is supported on both extremes by the shaft  14 . In this instance the rotor or basket  12  is not spinning, this is useful to exemplify what happens when the rotor or basket  12  undergoes a static imbalance, when putting identical imbalance loads  15 , in the same angular position but in a different plane. It is evident that the center of gravity CG of the rotor or basket  12  as well as the principal axis of compliance or inertia  62  move a bit from the axis of symmetry  61  of the shaft  14  arrangement in the rotor or basket  12 . 
         [0058]      FIG. 3  is useful to describe another phenomenon of imbalance, in this case, the loads  15  are placed at the extremes of the rotor or basket  12  but at 180° one from the other and in a different plane, making the center of gravity CG stay in its place, but modifying the principal axis of inertia  62  taking a certain angle with respect to the axis of symmetry  61  of the shaft  14  arrangement in the rotor or basket  12 . This angle will depend on the weight of the imbalance load  15 , supposing that they are the same as well as their position within the rotor or basket  12 . This phenomenon is commonly known as couple imbalance. 
         [0059]    On its part,  FIG. 4  shows another kind of imbalance, which is a combination of the cases presented in  FIGS. 2 and 3 , where the loads  15  are not placed symmetrically, and in fact, in this case they are not even equal; the loads  15  are placed randomly in any place within the cylindrical surface of the rotor or basket  12 . This causes the center of gravity CG to move towards a position out of the axis of symmetry  61 , where such position will depend on the position of the imbalance loads  15 , as well as on their weight. In this last instance the rotor or basket  12 , will tend to spin on the principal axis of inertia  62 , and not on the axis of symmetry  61 , axis on to which the bearings have been coupled, bearings that restrict four of the six degrees of liberty that the rotor or basket  12  could have, then producing an undesired vibration that could be so extensive that it would provoke the breakdown of a part, link or component. 
         [0060]    In the case of the washing machines, these have the peculiarity that only one of the extremes of the basket  12  is held on to the shaft  14 , leaving the other extreme free from the basket  12 , this free extreme tends to describe a quasi elliptical transfer orbit on the axis of symmetry  61 , what is commonly known as “pitch of the rotor”. When this happens, the basket  12  scrapes or patters the interior wall of the tub  13 , wearing both pieces out and the case could be that one of them eventually breaks. On the other hand, the stated “pitch” manifests itself as transmitted forces into the washing machine&#39;s cabinet making it “jump”, “dance” or even “walk”. The magnitude of these vibrations has an impact on the centrifugal velocity, that is to say that if there is not a system that correctly balances the basket  12 , the centrifugal velocity will have to be low, and obviously, when increasing the speed, the magnitude of the oscillations in the free extreme of the basket  12  will tend to be higher. 
         [0061]      FIG. 5  shows a diagram of a sub-washing machine  17  which has a basket  12  where its bottom  58  is coupled with a shaft  14 . The basket  12  is disposed in the interior of a tub  13 , which hangs from the supports  52  to the cabinet by means of rods  19  with shock absorbers  18 . It is noticeable that the basket  12  is crowned by an upper balance ring  10 , and a lower balance ring  63  has also been placed; with this we are trying to obtain a balance in two planes. To wit that the rotors with a length a bit greater than their diameter are considered large rotors; it is commonly known that these large rotors should preferably be balanced at least in two planes. And so, returning to  FIG. 5 , it is preferable that the basket  12  is crowned with a balance ring containing liquid in is interior; we can find an example of these rings in document MX/a/2007/016516; these balance rings are of very low cost. On the other hand, the lower balance ring  63  here proposed is a ring based on spheres, made of dense material such as steel, heat stable (thermo-fixed) plastic, thermoplastic rubbers with ceramic components, etc. This combination is advantageous because of low costs and because it is easy to manufacture, and it gives balance to the basket  12  in two planes, crowning it in its free part, precisely where there is greater space, with a balance ring with liquid, and integrally, at the exterior face of the bottom of the basket  58  a channel of circular trajectory is procured, where the spheres  59  will be running immerse in a drag fluid  60 , this channel is covered with a lid  64 . 
         [0062]    These balance rings work together, that is that the imbalance force IF caused by the imbalance mass or load  15  provokes a moment MCG in the center of gravity CG; this moment MCG, as well as the mentioned imbalance load  15  is counteracted by the resulting force FLD from the upper balance ring  10 , which also causes a moment in the center of gravity CG. On its part, the lower balance ring  63  also exerts a resulting force FB that also acts on the center of gravity CG. In an ideal situation, the addition of moments in the center of gravity CG are zero, herewith the equation of moments (1) that is obtained at the point CG and resulting forces (2) is the following: 
         [0000]        MGC =( FLD*d 1)+( FD*d 2)−( FB *( D 2 +D 3))  (1)
 
         [0000]        Fnet=FLD−FD+FB   (2)
 
         [0000]    where:
 
MGC=Moment in the center of gravity
 
Fnet=Net force resulting in the rotor or basket  12 
 
FLD=Force resulting from the upper balance ring  10 
 
d 1 =Distance from the center of gravity CG to the midpoint of the upper balance ring  10 
 
FD=Imbalance force caused by the imbalance mass or load  15 
 
d 2 =Distance from the center of gravity CG to the midpoint of the imbalance mass or load  15 
 
FB=Force resulting from the lower balance ring  63 
 
d 3 =Distance between the midpoint of the imbalance mass or load  15  to the midpoint of the lower balance ring  63 .
 
         [0063]    It fits to point out that from analyzing the equation of moments in the CG point, it is inferable that without the lower balance ring, the resulting moment would be positive, causing a conical vibration mode  68 , therefore the lower balance ring  63  reduces the magnitude of the resulting moment and directs to a softer movement of transfer of vibration  69  and consequently, to the alternation of forces transmitted to the suspension  19 , hence the vibration is reduced, just as analyzed in  FIG. 5 . 
         [0064]      FIG. 6  illustrates a typical balance ring with liquid, which comprises a series of blades  66  in its interior, in order to keep the liquid in small chambers and so to burst its flow within the toroidal chamber of the upper balance ring  10 , causing a great volume of working fluid in the upper balance ring  10  to agglutinate at 180° opposite from the imbalance load  15 . To wit that this kind of balance rings, due to the surface tension, as well as the high cohesion that molecules have in a liquid, a working fluid mass  67  is always in contact with the rest of the internal face of the external wall in the toroidal chamber of the upper balance ring  10 . This mass of working fluid  67 , which is straggled, generates a resulting force in the same direction of the imbalance force IF, increasing the imbalance force, decreasing the efficiency of the upper balance ring  10 , because it has a component that pushes power in favor of the imbalance load or mass  15 . As we have referred above, the washing basket  12  can be perceived as a large rotor, which is seized only by one of its extremes to the shaft  14 , being this condition a favorable one in order to place at the lower part or bottom of the basket  58  a second balance ring  63 , as shown in  FIG. 7 ; and it is pointed out that there are some design restrictions, these are: the space between the tub  13  and the basket  12  is minimal, because if it is too wide more water than necessary will have to be used when washing or rinsing, and consequently there will be an inefficient use of this vital liquid; another aspect is that if the distance or gap between the tub  13  and the basket  12  is wider, the washing machine will have to be taller, and on this assumption, a user (person) of short height would have many problems when taking the articles in the machine out, because they end up placed in the interior face at the bottom of the basket  58 . These and other reasons are why the space between the tub  13  and the basket  12  is considered, and why the designer has to consider it so that the distance does not increase, but rather decrease. 
         [0065]    Having expressed the above mentioned, the solution proposed by the present invention is placing a lower balance ring  63  through which a series of spheres  59  will run, made of a material with high density and very resistant to impact. These spheres  59  are immersed preferably in a liquid fluid known as drag fluid  60 , this way, when the basket  12  spins in a “ω” direction, both the drag fluid  60  and the spheres  59  adopt an opposite position from the imbalance load or mass  15 , reducing at a minimum the “e” distance and consequently the principal axis of inertia  62  will be closer to the axis of symmetry  61 , therefore the origin points “O” and “O′” will be very close. Making an analysis of a body not having a lower balance ring  63  we notice that these kinds of balance rings are efficient, to wit that the spheres  59  in unison with the drag fluid  60  contribute producing the resulting force FB, being a factor to be considered in the design that the mass of the spheres  60  as a whole to be greater or equal to the imbalance mass  15 , having the spheres  59  made of a material with high density. The space required to lodge these is minimized, which means that the diameter at the bottom of the basket  58  can be used, and so the diameter of the spheres  59  can be reduced, using a larger amount, or vice versa. 
       PREFERRED EMBODIMENT OF THE INVENTION 
       [0066]    As a first step, and to keep an order in the description, we will first deal with the construction of the upper balance ring  10 . And so,  FIG. 8  shows an exploded isometric drawing of the balance ring  10  where its basic elements are shown, a base  37  that contains blades  21 ,  22  or  23  in whichever of its configurations or combinations. This base is preferably molded by injection of some thermo-fixed polymer and its transversal section is similar to a “U” shape, with its walls configured as follows: an internal wall with a smaller diameter  30 , an internal wall with a greater diameter  31  and an inferior wall  33 . Concerning the internal upper wall  32 , it is formed by the cover  26 , which is similar to a ring with uniform thickness and should preferably be made by plastic injection molding. The cover  26  is jointed with the base preferably by process of ultrasound, “spin weld”, heat sealed or similar, or using some kind of sealer or agglutinant substance, to wit that the sealing has to be done very carefully, because the internal cavity of the balance ring  10  will be filled with some kind of working liquid, preferably calcium chloride or sodium chloride, which should not leak from its confinement. The stopper  25  is inserted into the hole provided for the filling of the working fluid in the balance ring  10 , once full, the hole is sealed with the stopper  25 . 
         [0067]      FIG. 9  illustrates a transversal section of a typical balance ring  10  already existing in the prior art, where we can appreciate the form of a blade  66  in the interior of the chamber in the balance ring  10 , in which we can see the different radius to be considered when calculating the volume of working liquid, which will vary depending on the loads to balance  15 , the geometry of the basket  12 , the capacity of the basket  12 , the kind of suspension  11 , among others, all these being the designer&#39;s responsibility and skill at all times. And so, the internal radius “r i ” has to be considered, in the majority of cases it coincides with the radius of the internal wall with a smaller diameter  30 , due to the design requirements, it is somewhat difficult to obtain a chamber with transversal section completely rectangular in the balance ring  10 ; therefore, it is necessary to calculate the imaginary internal radius, called “r iequivalent ” or r ie ; the external radius “r o ” implies no major complications. To wit that because the balance ring  10  is held on by its external wall to the internal upper wall of the basket  12 , the internal wall with a bigger diameter  31  makes it impossible to give a complex geometry to this external wall of the balance ring  10 , what results in few design options. It is therefore recommended that only the internal wall with bigger diameter  31  is given thickness, in order to form the external wall of the balance ring  10 . Another element to be considered when making calculations for the working liquid volume is the internal free height of the chamber at the interior of the balance ring  10 , which in the mentioned figure is represented with an “h”. With this information, together with the form of the blades to be used, we then proceed to calculate and when necessary to design the experiments that will allow us to determine the amount of working liquid to be used, which fluctuates between fifty to eighty percent of the total volume in the internal chamber of the balance ring  10 . 
         [0068]      FIG. 10  on its part shows an isometric ghost view of the internal geometry of a positive curved blade  22 . This denomination is taken from the direction of spinning ω of the basket  12 . As an example for the description of the preferred modality of the present invention but not limited to this particularity, the positive blades  22  origin from the internal wall with smaller diameter  30  extending and following the curve L θ  towards the internal wall with bigger diameter  31 , leaving a vertical space  39  between the positive curved blade  22  and the internal wall with bigger diameter  31 . In the preferred modality of the present invention, all the blades  21 ,  22  or  23  have the same height as the base  57  of the balance ring  10 , what makes their manufacture easier. Equally, in all the blades  21 ,  22  or  23 , their lower part coincides with the internal lower wall  33 , delimitating then the flow of working liquid through either the sides or the vertical spaces  34  and  39  between these blades  21 ,  22  or  23  and this internal wall with bigger diameter  31 , or through the upper part  36 , when the case is that there are bottom (lower) blades  28 . 
         [0069]      FIGS. 11 and 12  show a cross section drawing of the balance ring  10 , where it is possible to appreciate how the top (upper) blade  27  is conformed, these blades obstruct the flow of liquid between the lower internal wall  33  towards the upper internal wall  32 , originating from the internal wall with less diameter  31 , following the curve L θ , which in its parametric form is given by: 
         [0000]        L   θ ( x )= a (cos(θ+φ)+θ sin(θ+φ))  (3)
 
         [0000]        L   θ ( y )= a (sin(θ+φ)+θ cos(θ+φ))  (4)
 
       Where: 
       [0000]    
       
         a=constant with a preferential value of r ie    
         φ=phase angle in radians that defines the radial position at the beginning of the curve;
 
leaving a vertical space  39  between the upper blade  27  and the internal wall with bigger diameter  30 . This vertical space  39  allows the vertical flow of the undulating vertical current of the working liquid towards the interior of the internal chamber of the balance ring  10 . In the preferred modality of the invention, the upper blade  27  is conformed of a lower blade  28  that may have the form of the blades  21 ,  22  or  23 , their height being limited for manufacturing reasons to that of the base  37  of the balance ring  10 , complementing their height with a protuberance formed at the lower face of the cover  26 . This protuberance is known as complement of blade  38 , being it possible that its cross section takes the shape of blades  21 ,  22  or  23 , so that the upper face of the blade  28  is coupled with the lower face of the complement of blade  38 , and forming then a barrier with a floor surface in the internal lower wall  33  with a roof surface on the internal upper wall  32 . In an alternative modality, the complement of blade  38  can be shorter, this with the purpose of allowing the flow of the working liquid through the upper part of the blade  28  in order to allow the flow of working liquid in its horizontal component. The same effect or a similar one could be achieved making blades  28  of at least two different sizes, or if not available, also making the complement of blade  38  of at least two different sizes, taking them off completely from the lower face of the cover  26 , in order to leave space for the extended blades  28 , or a combination of the options above mentioned, which will have to be herewith written as if literally they were inserted. To wit that in any preferred modality, the blades  27  block completely the horizontal component of the flow of the working liquid, understanding that in the alternative modality, the upper blades  27  do allow the flow of the working liquid to have a horizontal component because there is a clearing  36  between the upper blade  28  and the upper internal wall  32 , or between the upper blade  28  and the complement of blade  38 .
 
       
     
         [0072]      FIG. 13  illustrates a cross section of the balance ring  10  in ghost view, and it is possible to appreciate the conformation of a blade  28 , where it is obvious that the blade  28  has the same height as the base  37  of the balance ring  10 . This figure illustrates a blade that originates from the internal wall with a smaller diameter  31  following the form L θ  towards the internal wall with a bigger diameter  30 , without touching it, and where there is a space or side  34  between the vertical face of the blade  28  and the internal wall with smaller diameter  31 . Having the blade  28  the same height as the base  37  of the balance ring  10 , there is a clearing  36  between the upper face of the blade  28  and the internal upper wall  32 . This way, the clearings  36  and the sides  34  and  39  allow the flow of working liquid to have horizontal components as well as vertical components, respectively. 
         [0073]      FIGS. 14 ,  15 ,  16  and  17  make it possible to understand the assembly of a base  37  with a cover  26 . In order to easily assemble the base  37  with the cover  26 , a localizer  40  was conceived, and which, in a descriptive but not limitative way for purposes of describing the best way to carry out the invention, comprises a pair of walls in high relief  40  in the internal lower wall  32 , which can be appreciated in  FIGS. 14 and 15 . These walls in high relief or localizer  40  have a bay with a duct forming a “Y”, which is inverted as shown in the figures just mentioned, in this occasion the bay is wide and it allows to localize as well as to guide the upper part of the blade  28 , making it possible for the cover  26  to always rest in the right position accordingly with the base  37  when assembling, what is illustrated in  FIGS. 16 and 17 , and hence avoiding localization errors that could cause an undesirable malfunctioning of the balance ring  10 . 
         [0074]      FIGS. 18 and 19  are useful because they identify and show the different kinds of blades  21 ,  22 ,  23 , to wit that the base  26  can lodge different types of blades. And so the prior art describes arrangements of straight radial blades, that as discussed in the chapter concerning background, as well as in the theoretical statement, these arrangements are not optimal. So there is  FIG. 18  that presents the preferred modality of the invention, which comprises an arrangement of positive curved blades  22  with negative curved blades  23 , with their respective clearings  34  and  39 .  FIG. 19  illustrates an alternative modality of the invention that provides an arrangement of positive curved blades  22  with straight blades  21 . This is comprehensive because of the spinning direction of the basket  12 , and it is obvious for a technician in the matter that if the basket  12  spins in opposite direction the use of negative curved blades  23  instead of the positive curved blades  22 , could produce better results. 
         [0075]      FIG. 20  represents a Bode plot in which the angular velocity of the basket  12  is represented graphically, in revolutions per minute (rpm) versus the peak-to-peak vibration measured at the front face of the washing machine&#39;s cabinet. For this graphic the walking threshold is of approximately 1 mm. This means that, given an angular velocity, if the peak-to-peak vibration exceeds a millimeter, the washing machine will tend to move randomly towards any direction. In this graphic we can also appreciate the vibrations resulting from the use of different arrangements of the balance ring  10 . For this purpose, using the same sub-washing machine  17 , with the same imbalance load  15 , several balance rings  10  were placed with different internal arrangements, which for the curve “A0” a conventional balance ring  10  was used, and which uses straight radial blades  21 . It is pointed out that bellow the 100 rpm the highest peak is of 2 mm, and then, above the 600 rpm the vibration separates from the other curves, indicating that the design of a conventional balance ring does not withstand high rpm in an optimal manner. As can be deduced from this graphic, above the 800 rpm, there is an existing difference of approximately 1 mm from the rest of the curves. It is also noticeable that when getting closer to the 900 rpm it has a peak higher than 3 mm, this way indicating the incapacity of this kind of balance rings  10  to balance loads  15  at more than 600 rpm. On the other hand, the curve “A2” has an arrangement of twelve positive curved blades  22  with twelve straight blades  21  alternated, noticeably diminishing the vibration compared to the base curve “A0”, and proving then that the molecules “P”, thanks to the curvature of the blades  22 , reach faster from their stable state towards the internal wall with larger diameter  31 , and so it is inferable that the transitional state is shorter (considering a constant acceleration), also producing vibrations of lesser magnitude (of 1 mm approximately) and functioning much better between 600 rpm and 850 rpm. The curve “A3” is also noticeable in the graphic of  FIG. 20 , describing a behavior similar to that of “A2” and corresponding to a second preferred configuration of the balance ring with twelve positive curved blades  22  and thirteen straight radial blades  21 . 
         [0076]      FIG. 21  shows another Bode plot, for the left lateral face of the washing machine, for this measurement the walking threshold presents itself at about 1.4 mm of peak-to-peak vibration, as can be observed in the diagram; the three curves “A0”, “A2” and “A3” behave similarly from zero to seven hundred rpm. Above this last angular velocity, the vibration caused by “A0” starts getting higher than “A2” and “A3”, rocketing higher than eight hundred rpm, having a peak higher than 3.5 mm close to the nine hundred rpm, which is about 2 mm higher than “A2” or “A3”. Also, from an analysis of the Bode plot afore commented, it can be inferred that the conventional balance rings  10  with straight radial blades  21  are not adequate for high rpm, because when the rpm are increased their capacity to balance is significantly decreased, situation that does not occur with the configurations here proposed. 
         [0077]      FIG. 22 , on its part, illustrates the arrangement of two balance rings  10  and  63  disposed in two different planes corresponding to the extremes of the basket  12 . It is noticeable that the upper balance ring  10  is crowned onto the basket  12  in its upper part, set up on the cylindrical wall. In the lower part of this cylindrical wall is the bottom of the basket  58 , which is manufactured preferably with some kind of injectable polymer. This one mechanically couples the hub  16  into its center part and is a part of the reinforcement mechanism, manufactured preferably with some metal or light metallic alloy, in order to make it more resistant to the stress transmitted from torque via the shaft  14  to the basket  12 ; the hub in its part transmits the energy towards the bottom of the basket  58 , in order to have them all rotate in unison as a whole. The track or channel  57  is located on the exterior face of this bottom of basket  58 ; in this channel  57  the spheres  59  as well as the drag fluid  60  will be lodged. These together are covered with the lid  64  of the lower balance ring  63 . With the purpose of following the order of the description, we will now give the details of the particular construction of the lower balance ring  63 . 
         [0078]      FIG. 23  shows an exploded drawing of the bottom of basket  58  with channels. It has a series of radial reinforcements  72  and circumferential or annular reinforcements  73 , that is, that this piece withstands the weight of the wash liquor and the weight of the objects to be washed already introduced into the basket  12 . It is also able to support the vibration, as well as the dynamic loads exerted on it during the washing and centrifuge stages, hence being it another function to lodge the track or channel  57  where the spheres  59  will be spinning. And so, this piece not only has contention functions, but also contributes to the balance of the lower plane of the basket  12 . All the previous information can be observed in  FIG. 25  as well.  FIG. 26  shows the bottom of basket  58  from an upper view, which has the channel or track  57  at its lower part. 
         [0079]      FIG. 24 , on its part, shows a series of spheres  59 , that are manufactured with a high density material, with good resistance to impact, with a high fluidity point, anticorrosive and hardness, among other properties. The material usually recommended is steel, and it can be low carbon steel with heat treatment by cementing or stainless steel, the choice inextricably depends on the drag fluid  60  that will be used, although other materials could be used, like a plastic or thermo-fixed polymer with a kind of specific combination of a ceramic material. The number of spheres  59  to be used, as mentioned a few lines above in the theoretical approach section, respond to: in the first place, the weight or force of the load to be balanced; in the second place, it is preferable not to use more spheres than necessary because it would increase the manufacturing costs; and in the third place, the particular diameter of the spheres  59 , which is related to the radius of the track or channel  57 . And so, experimenting with these variables we can obtain, first of all, the graphic of  FIG. 30 , in which we can observe in the vertical axis, the force in Newtons that is exerted by a specific number of spheres  59  all with the same specific diameter, in a track  57 . Analyzing this graphic we can delimit the number of spheres  59  to between fifteen and thirty, to wit that the force required to counteract an imbalance load  15 , in a basket  12  is higher than 700 N. The graphic in  FIG. 31  is drawn from the equations (1) and (2), and for that, for the calculations a one kilogram imbalance load  15  was used, at a maximum speed of 850 rpm. In the left vertical axis the scale of the resulting force in Newtons is obtained. In the horizontal axis the number of spheres  59  is represented. In the second vertical axis located at the right of the graphic mentioned, the net momentum resulting in the rotor or basket  12  when adding the lower balance ring  63  in N*m is obtained. From here we can deduce that the number of spheres  59  fluctuates between fifteen and twenty five spheres  59 . This range in the number of spheres  59  guarantees that the basket  12  will not scrape the tub  13 , reason for which the quasi-elliptic trajectory or “pitching” of the basket does not have such magnitude as to cause these pieces to have contact between them, what according to experience is an acceptable parameter of imbalance in a washing machine. So, the only decision left to the designer is that when considering the number of spheres  59  to be used, the cost of the spheres  59  versus the capacity of balancing should also be considered. 
         [0080]      FIGS. 27 and 28  show the lid  64  of the lower balance ring  63 , this lid can be adhered to or coupled with the bottom of the basket  58  using mechanical methods like “spin weld” or ultrasound, heat sealed, or using some kind of glue or agglutinant substance, what should guarantee at all times that the chamber formed by the track or channel  57  and the lid  64  will be hermetically sealed. To wit that the drag fluid  60  to be introduced has a viscosity at 40° C. of between 200 and 300 cSt, with a inflammability temperature higher than 300° C. The acidity in the drag fluid  60  should also be taken care of, namely, that the acidity could age or damage the spheres  59 , or it could ruin the manufacturing material of the bottom  58 . The designer should have in mind that the selection of the drag fluid  60  is a factor that needs to be considered in the compliance of the applicable environment legislation (standards). 
         [0081]    The design of the bottom of basket  58  is such that it provides flexibility for its manufacture. Namely, that the bottom of basket  58  is convertible: with or without track  57 , what gives it adaptability according to the washing machine model, which, for reasons of business decisions, costs and marketing, among others, the choice could be not to provide it with a balance ring containing spheres  59  at the bottom of basket, as is shown in  FIG. 29 , in which case, the lid  64  is not placed and in the injection mold the insertion is changed so that the radial reinforcements  72  are formed in a continuous manner within the space of the track  57 , hence at the bottom of basket  58  there is very good rigidity thanks to an adequate design of the radial and annular reinforcements  72  and  73 . Besides, if we wish to include the balance ring with spheres  59  and form a channel  57  by changing the insertion, and interrupt the radial reinforcements  72 , the radial ribs  71  in the lid  64  give enough rigidity and mechanical resistance to support the static washing load, as well as the efforts resulting from rotation and the vibration. 
         [0082]    The graphic in  FIG. 32 , on its part, illustrates the important reduction of vibration or imbalance when implementing a lower balance ring  63  into a basket  12 , using a balance ring  10  with liquid and blades with involute curve, avoiding the peak generated in the vicinity of seven hundred rpm, showing the angular velocity spectrum of the basket  12 , at all times, a more uniform behavior. 
         [0083]    It is important to point out that the modalities here described should not be interpreted restrictively, to with that they are illustrative of the best way to carry out the invention here commented, that is, that several modifications and variations can be foreseen by a technician with some knowledge of this particular technique; these modifications and variations should not be left out from the legal protection of the following claims.