Abstract:
A dishwasher having a wash chamber or tub including a sump and a side wall. A pump is fluidly connected with the sump and a supply tube is supported adjacent the tub side wall and receives wash liquid from the pump, the supply tube has a manifold portion including a plurality of outlet openings. A coupling retainer is connected to the supply tube and has a plurality of funnel shaped coupling ports corresponding in number and spacing to the outlet openings of the supply tube. Each of the coupling ports includes a center opening which is provided with a sealing surface. A valve member supports a plurality of valve elements for sealing the outlet openings and is captured between the coupling retainer and the supply tube such that the valve elements generally align with the coupling parts.

Description:
This application is a divisional of application Ser. No. 09/541,267 filed Apr. 3, 2000 now U.S. Pat. No. 6,431,188. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is directed to dishwashers and more particularly, to dishwasher spray arm feed systems. 
     2. Description of the Related Art 
     Modem dishwashers include a tub and an upper and lower rack or basket for supporting soiled dishes within the tub. A pump is provided for recirculating wash liquid throughout the tub to remove soils from the dishes. Typically, larger dishes are carried on the lower rack or basket which is moveable in or out of the tub for loading and unloading. A lower wash arm that rotates about a vertical axis is provided beneath the lower rack. An upper rack is also provided for articles such as cups and glasses, and it is mounted on rollers and tracks to also be moveable in or out of the tub for loading and unloading. It has been found that a single rotary lower wash arm does not always give good washability performance because the spray path can be blocked by dishes on the lower rack and very little water may reach some articles on the upper rack. Therefore, nearly all dishwashers include an upper or second level spray mechanism beneath the upper rack to spray upward directly on the articles in the upper rack and downwardly on to the articles on the lower rack. 
     Lower spray arms are generally mounted directly above the recirculation pump and receive wash liquid directly therefrom. Different approaches have been taken to rotatably support a lower spray arm and provide a thrust bearing surface. For example, U.S. Pat. Nos. 3,866,837 and 5,427,129 disclose different spray arm bearing support systems. 
     The upper or second level spray system may include a rotating wash arm similar to the main or lower wash arm which may be mounted directly to the upper rack and receive wash liquid through an upper arm feed system. Different approaches have been taken to feed and rotatably support second level spray arms which are associated with an upper rack or basket. One approach for an upper arm feed system is to utilize a tower mounted to the lower rack which receives wash liquid from the lower spray arm and has an open upper end such that wash liquid is sprayed through the tower upwardly into a bottom inlet in the upper spray arm for supplying the upper arm with wash liquid. U.S. Pat. No. 5,330,102 discloses a center tower type system for feeding an upper spray arm having a bottom inlet. 
     Another approach to supplying wash liquid to an upper rack spray system is to feed wash liquid to an upper spray arm through a liquid conduit which is mounted on the exterior of the dishwasher tub. U.S. Pat. Nos. 4,172,463, 4,004,600 and 5,211,190 are all examples of this type of approach. Generally, a discharge outlet from the wash pump is provided which is connected to an liquid conduit which is routed along the exterior of the dishwasher tub. The liquid conduit passes through the tub back into the wash chamber in an area near the upper rack to feed wash liquid to the upper spray arm. 
     The upper spray arm of a dishwasher may also be fed through the use of an internally disposed supply conduit. In such case, the wash pump of a dishwasher may be provided with a discharge outlet for supplying a conduit which extends along the inside surface of the dishwasher tub to a location near the upper dishwasher rack to feed wash liquid to the upper spray arm. 
     Upper dishracks are often supported in a manner that allows for vertical height adjustment. U.S. Pat. Nos. 5,474,378 and 4,097,099 illustrate adjustable upper rack support systems. 
     Adjustable upper racks require upper spray arm feed systems which can accommodate the adjustable position of the upper rack. In the past various upper rack feed system designs have been used which can accommodate variable position upper racks. For example, U.S. Pat. No. 5,823,211 discloses a dishwasher having at least one adjustable height rack or basket to which an associated spray arm and inlet tube are secured. The inlet tube is disposed horizontally and is connected by a coupling to a supply line secured to a side wall of the tub. An open connection fitting and two closed blind fittings protrude toward the inlet tube. The coupling has two openings into which the connecting fitting and one of the blind fittings respectively, protrude. The adjustable basket can be moved between an upper and lower position wherein the open connection fitting supplies wash liquid to spray arm associated with the adjustable height rack. 
     EP 0 401 767 B1 is also directed to a feed system for supplying liquid to a spray arm associated with an adjustable height basket. In this reference, the upper spray arm is equipped with a connecting pipe extending horizontally toward the back wall of the tub and adapted to join up in a detachable fashion with a water supply pipe extending vertically in correspondence with the back wall of the tub. To supply the upper spray arm with wash liquid in each of two vertical positions, the connecting pipe is designed at one end with a box collector extending upward and equipped with two vertically spaced outlets. The collector is provided with check ball type valve means adapted to make the supply pipe communicate only with the outlet of the collector which is coupled with the connecting pipe. 
     SUMMARY OF THE INVENTION 
     The present invention provides a dishwasher having a wash chamber or tub including a sump and a side wall. A pump is fluidly connected with the sump. At least one adjustable height basket is supported within the tub. A supply tube is supported adjacent the tub side wall and receives wash liquid from the pump, the supply tube has a manifold portion including a plurality of outlet openings. A coupling retainer is connected to the supply tube and has a plurality of funnel shaped coupling ports corresponding in number and spacing to the outlet openings of the supply tube. Each of the coupling ports includes a center opening which is provided with a sealing surface. A valve member supports a plurality of valve elements for sealing the outlet openings and is captured between the coupling retainer and the supply tube such that the valve elements generally align with the coupling ports. A spray arm is associated with the adjustable height basket and has a feed tube extending toward the supply tube. The feed tube has a coupling end wherein the coupling end is insertable into one of the coupling ports for fluidly connecting the feed tube to the supply tube. The coupling end is sealingly engaged by the sealing surface upon insertion into one of the coupling ports and opens the valve element corresponding to the coupling port into which the coupling end is inserted. Water pressure within the manifold is used to seal the coupling ports which do not receive the coupling end. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a dishwasher including a spray arm system in accordance with the present invention. 
     FIG. 2 is a schematic, cross-sectional view of the dishwasher of FIG. 1, showing the dishracks mounted within the tub and the spray arm feed system. 
     FIG. 3 is a perspective, exploded view of the spray arm coupling system of the present invention including the spray arm feed tube. 
     FIG. 4 is a perspective, exploded view of the spray arm coupling system of the present invention, showing the coupling system from a different angle than shown in FIG.  3 . 
     FIG. 5 is a side sectional view of the coupling system of the present invention with the coupling end of the feed tube inserted into the top coupling port. 
     FIG. 6 is a perspective view of a single height coupling system which can be provided on the supply tube of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In accordance with the invention as shown in the drawings, and particularly as shown in FIGS. 1 and 2, an automatic dishwasher generally designated  10  includes an interior tub  12  forming an interior wash chamber or dishwashing space  14 . The tub  12  includes a sloped bottom wall  16  which defines a lower tub region or sump  18  of the tub. A pump assembly  20  is located in the bottom wall  16  and operates to draw wash liquid from the sump and pump it to a lower spray arm assembly  22 , a mid-level spray arm assembly  24  and an upper spray arm  20  assembly  34 . The lower spray arm  22  is positioned beneath lower dishware rack  26  and the mid-level spray arm assembly  24  is associated or positioned below an adjustable height dishware rack or basket  28 . 
     The lower spray arm assembly  22  may be mounted to the upper portion of the pump assembly  20  and receive wash liquid from the pump. Since the mid level spray arm assembly  24  and upper spray assembly  34  are remote from the pump, means must be provided to supply wash liquid remotely to these upper spray devices  24  and  34 . To that end, a supply tube  30  extends generally rearwardly from the pump assembly  20  to the rear wall of the tub and then runs upwardly to supply wash liquid to upper spray devices  24  and  34 . 
     According to the present invention, the spray arm  24  associated with the adjustable height basket  28  includes a rear feed tube  32  which is fluidly connected with the supply tube  30  through the use of a coupling system  40 . The coupling system  40  is designed to couple the supply tube  30  to the feed tube  32  when the adjustable rack  28  is at a plurality of different heights. The coupling system  40  further accommodates a single height coupling arrangement. 
     As best seen in FIGS. 3 and 4, the coupling system  40  includes an enlarged portion or manifold  42  formed into the supply tube  30 . The manifold portion  42  includes a plurality of outlet openings  44 . Two outlet openings  44  are shown in the present embodiment but more outlet openings could readily be provided. In the disclosed embodiment, a coupling retainer  46  is connected to the supply tube  30  in the area of the manifold  42  such that a plurality of funnel shaped coupling ports  48  formed into the retainer  46  are aligned with and overlay the outlet openings  44 . The coupling ports  48  include center openings  48   a . Although the coupling retainer  46  may be connected to the supply tube  30  using any known connection means, in the disclosed embodiment the retainer  46  is snap connected using a plurality of holes or openings  50  which form snap hooks and which are provided on the coupling retainer  46  and snap over a corresponding number of ribs or bumps  52  formed into the manifold portion  42 . 
     The coupling system  40  further includes a valve member  54  and a gasket member  56  which are both captured between the coupling retainer  46  and the manifold portion  42 . The valve member  54  includes a plurality of valve elements  58 . The valve elements  58  in the disclose embodiment are flapper type elements having generally circular bodies joined to the main portion of the valve member  54  by relatively narrow connecting flex sections. The gasket member  56  includes a plurality of openings  60  which form sealing surfaces. The valve member  54  and the gasket member  56  are positioned between the coupling retainer  46  and the manifold portion  42  in such a manner that the valve elements  58  and the gasket openings  60  are generally aligned with the center openings  48   a  of the coupling ports  48 . 
     While the gasket member  56  is shown as a separate element from the coupling retainer  46 , alternatively, the sealing surfaces provided by the gasket member  56  could be integrally formed into the coupling retainer  46 . This could be done, for example, using a two step over molding processes. In such a case, the center openings  48   a  of the coupling retainer  46  would be provided with annular sealing surfaces. Accordingly, it can be understood that the center openings  48   a  can be provided with sealing surfaces through either a gasket member  56  or as an integral part of the coupling retainer  46 . 
     The feed tube  32  is designed to fluidly couple to the supply tube via the coupling system  40  and includes a coupling end  70 . The coupling end  70  is shown cylindrical but could be formed with other cross-sectional shapes as well. The connecting end  70  of the feed tube  32  may be formed as part of a connecting member  72  which may be formed as a separate member from the main portion of the feed tube  32  as shown in the disclosed embodiment. Alternatively, the connecting member  72  may be formed as an integral part of the feed tube  32 . The connecting member  72  includes a probe element or finger  74  extending from the connecting end  70 . To securely locate the coupling end  70  of the feed tube  32 , a hanging support element  76  engages the dishware basket  28  and includes a U-shaped portion  78  extending downwardly to support the coupling end  70 . A slotted flange  80  may be formed onto the connecting member  72  to engage the U-shaped portion  78 . When the coupling system  40  is properly assembled together, the coupling ports  48  are oriented such that the coupling end  70  can be inserted thereinto. 
     During operation of the dishwasher, the dishware basket or rack  28  may be pulled out of the tub along guides (not shown) and loaded with soiled dishware. After loading, the dishware rack  28  is thrust into the dishwasher at one of a plurality of selectively adjustable heights. The adjustable height positions of the rack  28  cause the location of the coupling end  70  of the feed tube  32  to align with one of the coupling ports  48 . As best seen in FIG. 5, in the process of inserting the rack  28  back into the tub  12 , the finger  74  is inserted into the coupling port  48  and causes the valve element  58  to open. Moreover, the cylindrical coupling end  70  inserts into the coupling port  48 , through the gasket opening  60  and into the manifold area  42  of the supply tube  30  such that that cylindrical coupling end is sealingly engaged by the gasket opening  60 . In this manner, fluid passing through the supply tube  30  is directed into the feed tube  32  through the coupling system  40  such that the wash arm  24  may be supplied with wash liquid. 
     As can be seen in FIG. 5, any coupling port  48  which does not receive the coupling end  70  of the feed tube  32  is sealed closed by a valve  58 . Any valve  58  which is not opened by the coupling end  70  seals against gasket member  56  under the pressure of the wash liquid within the supply tube  30 . Moreover, the coupling system  40  is capable of operating wherein all of the coupling ports  48  are sealed closed such as may occur if the rack  28  and associated feed tube  32  is removed. This may be done to wash a particularly large dish item or items. 
     The present invention contemplates that the outlet openings  44  provided in the manifold portion  42  may be formed in a unique manner such that one, two or more outlet openings  44  can be accommodated using the same tool. In particular, the supply tube  30  may be formed as a blow molded part which includes the manifold portion  42 . A plurality of protrusions or closed fittings are molded into the manifold portion  42 . The protrusions may then be selectively opened through a secondary operation after the molding of the supply tube  30 . The number of openings  44  can be varied to accommodate a single position rack  28  or a rack  28  which is adjustably supported. 
     FIG. 6 illustrates a single position coupling assembly  90 . In this embodiment, only a single outlet opening  44  is provided in the manifold portion  42 . A coupling retainer  92  is snap connected to the manifold  42  for engagement with a feed tube assembly (not shown). 
     The present invention, therefore, provides for a unique coupling assembly which provides for coupling an adjustable height spray arm system to an internal supply tube. The coupling arrangement is simple and cost effective. The present invention further provides a single or multiple port coupling arrangement using a common supply tube design. 
     The present disclosure describes preferred embodiments of the invention, however, the invention is not limited to these embodiments. For example, the coupling ports are shown as funnel shaped but could readily be configured in a different manner. The coupling retainer could have a plurality of ribs which direct the coupling end to coupling ports which are mere openings provided in the coupling retainer. Other variations may be made from the described preferred embodiments which are contemplated to be within the spirit and scope of the invention as set forth in the appended claims.