Patent Application
20100275957
Contemporary automatic dishwashers for use in a typical household include a tub and an upper and lower rack or basket for supporting soiled utensils within the tub. A spray system and a filter system are provided for re-circulating wash liquid throughout the tub to remove soils from the dishes. Typically, larger dishes such as casserole dishes that have a propensity to be heavily soiled are carried on the lower rack and lighter soiled dishes such as cups and glasses are provided on an upper rack. The racks are generally configured to be moveable in or out of the tub for loading and unloading.
The spray systems have rotating spray arms and sprayers that are rotated by the propulsion force of the exiting wash liquid, which is dependent on the pumping of the wash liquid. Thus, the rotation of the spray arms and sprayers is directly linked to the spraying of wash liquid.
In one embodiment, the invention relates to an automatic dishwasher configured to perform a cycle of operation to clean utensils. The dishwasher comprises a rotatable spray arm located beneath the first dish rack and at least one rotatable sprayer located within the wash chamber, with a drive link coupling the rotation of the rotatable spray arm and the rotatable sprayer, and a driver coupled to and moving one of the rotatable spray arm, rotatable sprayer, and drive link, and thereby simultaneously rotates the rotatable spray arm and the rotatable sprayer.
In the drawings:
Referring now to the drawings, wherein like numerals indicate like elements throughout the views,
As used in this document, the term utensils is meant to be generic and cover any item, singular or plural, that may be washed in a dishwasher, including, without limitation: silverware, dishes, plates, bowls, glassware, pots, and pans.
A spray manifold 40 may be positioned on the rear wall 18 of the interior tub 12. At least one rotatable sprayer 42 is provided in the interior tub 12 in fluid communication with the spray manifold 40.
Referring to
A pump assembly 21 can be located in or around a portion of the bottom wall 14 and in fluid communication with the sump 38 to draw wash liquid from the sump and to pump the liquid to at least one spray arm assembly 22. Additionally, the dishwasher 10 may have a mid-level spray arm assembly 23 and/or an upper spray arm assembly 24, with the liquid selectively pumped through a fluidly-connected supply tube 25 to the assemblies 22-24 for selective washing.
In this exemplary embodiment, the first spray arm assembly 22 is positioned beneath the first dish rack 26, the mid-level spray arm assembly 23 is positioned between the upper dish rack 27 and the lower dish rack 26, and the upper spray arm assembly 24 is positioned above the upper dish rack 27. The lower spray arm assembly 22 and the middle spray arm assembly 23 spray a flow of wash liquid in a generally upward direction over a portion of the interior of the tub 12. The upper spray arm assembly 23 sprays a flow of wash liquid in a generally downward direction.
The dishwasher 10 further has may have a drive link 48 operably coupling the rotation of at least one rotatable spray arm 22 and at least one rotatable sprayer 42. The drive link 48 may be one or more gears, crank, belts, a combination thereof, or any other suitable linkage system. A driver 50 may be coupled to and moving one of the rotatable spray arm 22, rotatable sprayer 42, and drive link 48, and thereby simultaneously rotates the rotatable spray arm 22 and the rotatable sprayer 42. The driver 50 may have a motor 52 located virtually in any location, for example inside of the tub 12, behind or under the tub 12 of the dishwasher 10.
An exemplary embodiment illustrated in
Turning now to
The first and second wash zones may have the same or different characteristics, such as force, volumetric flow rate, etc. The third zone 32 has at least one of a greater intensity, pressure, and volumetric flow rate than each of the first and second wash zones to form a more intensified wash zone. Thus, the third wash zone 32 may be designed to enable heavily soiled utensils, such as casserole dishes, to receive the traditional spray arm wash, as well as an additional concentrated wash. Thus, a dishwasher having such a zone will not only provide better washing performance for heavily soiled dishware, but will provide overall improved wash performance.
Referring now to
Each rotatable sprayer 42 may be implemented as a sprayer head with at least one spray opening 44. Each opening 44 may have any suitable shape, size, number, arrangement and angle orientation with respect to the spray head 42 or with respect to the spray manifold 40. The manifold 40, spray heads 42 and wash liquid supply system may further be provided with other components such as circular front and back plates of the spray head, a wash liquid valve, etc. Those components are not germane to the present invention and therefore will not be described in detail herein. However, a detailed description of those components may be found in commonly assigned U.S. Patent Publication No. US 2005/0150529 to Vanderroest et al., incorporated here in its entirety.
The drive link 48 may be of any suitable type, such as for example, a crank, a gear, a gear train, a gear belt or a may be a combination of thereof. The drive link 48, according to this embodiment, has the driver 50 actively rotating the plurality of the sprayers 42 via an optional drive gear 58 attached to the shaft 56. The drive gear 58 may have any suitable configuration and size and may be directly or indirectly coupled with one or more sprayers 42. Each sprayer 42 may have circumferential engagement surface 60 as a part of the drive link 48. The circumferential engagement surface 60 may have a plurality of teeth for mutual gear engagement of the sprayers 42 with each other and with the optional drive gear 58. The gap between teeth may be selected to lessen soil build-up during the operation of the dishwasher 10. During operation of the dishwasher 10, a rotation speed of sprayers 42 is controlled by the speed of the driver 50 and by the gear ratios employed in the design. A gear train may be provided having the first drive gear 58 carried by the rotatable spray 22 arm, a second gear 66 carried by the rotatable sprayer and an optional third idler gear 68 operably coupling the first and second gears. The drive link 48 may be operably coupled to and drive one of the first, second and third gears.
Referring now to
The spray manifold 40 is not limited to this configuration; rather, the spray manifold 40 can be located in virtually any part of the interior tub 12. Alternatively, the manifold 40 can be positioned beneath the lower dish rack 26 adjacent or beneath the lower wash arm assembly 22. The spray manifold 40 can also extend across virtually any width of the interior wash tub 12, or can be limited to extending to only one side of the supply tube 25. Moreover, the driver 50 may be coupled with at least one of the sprayers 42, which in turn is coupled with any movable part of the dishwasher 10 and/or with any or all spray arms 22, 24 and 26. Alternatively, the driver 50 may be coupled with any movable part of the dishwasher 10, which in turn is coupled with the spray heads 42 via a suitable drive link 48.
As illustrated in
As described above, the driver 50 actively controls the rotation of the sprayers 42 and any movable part coupled to the at least one sprayer 42. This active control of the spray heads and one or more spray arms provides additional opportunities for improved washing action of the washing machine 10. Moreover, the active control of the sprayers 42 and one or more spray arms at a variety of speeds enhancing the cleaning effectiveness of the zone wash sprayer. The rotation of the wash liquid stream covers a greater soil area with less volume of wash liquid. Because less volume is used, increased of wash liquid pressure is maintained at all zones and sprayers, thereby enhancing the overall cleaning effectiveness of the dishwasher. A reverse direction of rotation of the spray heads and the spray arm also subjects soil particles on utensils and dishes to streams of wash liquid that approach the particles from different directions. This enhances the lifting and removal of soil particles from the utensils and dishes.
While the present invention is described in terms of a conventional dishwashing unit as illustrated in
While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation. Reasonable variation and modification are possible within the scope of the forgoing disclosure and drawings without departing from the spirit of the invention which is defined in the appended claims.
