US20120279536A1

US20120279536A1 - Dishwasher spray arm with diverting valve

Info

Publication number: US20120279536A1
Application number: US13/100,420
Authority: US
Inventors: Joseph W. Adams; Kristopher L. Delgado; Jordan R. Fountain; Sathish A. Sundaram
Original assignee: Whirlpool Corp
Current assignee: Whirlpool Corp
Priority date: 2011-05-04
Filing date: 2011-05-04
Publication date: 2012-11-08

Abstract

An automatic dishwasher having a rotatable sprayer includes a nozzle that may be selectively fluidly coupled to a fluid supply by a control valve.

Description

BACKGROUND OF THE INVENTION

Contemporary automatic dishwashers for use in a typical household include a tub at least partially defining a treating chamber within which is provided at least one rack or basket for supporting soiled dishes within the tub. A spray system may be provided for recirculating wash liquid throughout the tub to remove soils from the utensils. The dishwasher may have a controller that implements a number of pre-programmed cycles of operation to wash utensils contained in the tub.

SUMMARY OF THE INVENTION

The invention relates to an automatic dishwasher having a rotatable sprayer that includes a housing with a first nozzle, a second nozzle, and a hub, which is rotatable about an axis of rotation. A first liquid conduit extends from the first nozzle to the hub to fluidly couple the first nozzle to the hub and a second liquid conduit extends from the second nozzle to the hub to fluidly couple the second nozzle to the hub. A liquid supply fluidly couples to the hub and a control valve is provided within the hub and has a valve body, which is rotatable about the axis of rotation. Liquid from the liquid supply is selectively supplied to the first and second nozzles by controlling the relative rotation between the valve body and the housing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a dishwasher having a lower rotatable sprayer according to one embodiment of the invention.

FIG. 2 is a partial perspective view of the rotatable sprayer of FIG. 1 with a drive system for the spray arm shown in phantom lines within a hub of the spray arm.

FIG. 3 is a cross-sectional view of the lower rotatable sprayer of FIG. 2.

FIG. 4 is a schematic view of a controller of the dishwasher of FIG. 1.

FIG. 5 is a perspective view of a rotatable sprayer according to a second embodiment of the invention.

DESCRIPTION OF AN EMBODIMENT OF THE INVENTION

FIG. 1 is a schematic illustration of an automatic dishwasher 10 in accordance with a first embodiment of the invention. The dishwasher 10 shares many features of a conventional automatic dishwasher, which will not be described in detail herein except as necessary for a complete understanding of the invention. While the present invention is described in terms of a conventional dishwashing unit, it could also be implemented in other types of dishwashing units, such as in-sink dishwashers or drawer-type dishwashers.
As illustrated, the dishwasher 10 includes a chassis 12 which contains a wash tub 14 that at least partially defines a treating chamber 16 with an access opening in the form of an open face. A cover, illustrated as a door 18, may be hingedly mounted to the chassis 12 and may move between an opened position, wherein the user may access the treating chamber 16, and a closed position, as shown in FIG. 1, wherein the door 18 covers or closes the open face of the treating chamber 16.
Utensil holders in the form of upper and lower racks 20, 22 are located within the treating chamber 16 and receive utensils for being treated. The racks 20, 22 are mounted for slidable movement in and out of the treating chamber 16 for ease of loading and unloading. As used in this description, the term “utensil(s)” is intended to be generic to any item, single or plural, that may be treated in the dishwasher 10, including, without limitation; dishes, plates, pots, bowls, pans, glassware, and silverware.
A spray system is provided for spraying liquid in the treating chamber 16 and is provided in the form of an upper sprayer 40, a mid-level sprayer 42, and a lower sprayer 44. Upper sprayer 40 is located above the upper rack 20 and is illustrated as a fixed spray nozzle that sprays liquid downwardly within the treating chamber 16. Mid-level rotatable sprayer 42 and lower rotatable sprayer 44 are located, respectively, beneath upper rack 20 and lower rack 22 and are illustrated as rotating spray arms. The mid-level spray arm 42 may be rotatably mounted to the bottom of the upper rack 20 and may provide a liquid spray upwardly through the bottom of the upper rack 20. The lower rotatable spray arm 44 may be rotatably mounted to the recirculation pump 36 beneath the lower rack 22 and may provide a liquid spray upwardly through the bottom of the lower rack 22. The mid-level rotatable sprayer 42 may optionally also provide a liquid spray downwardly onto the lower rack 22, but for purposes of simplification, this will not be illustrated herein.
A recirculation system is provided for recirculating liquid from the treating chamber to the spray system. The recirculation system may include a sump 26 and a pump assembly 32. The sump 26 collects the liquid sprayed in the treating chamber 16 and may be formed by a sloped or recess portion of a bottom wall 24 of the tub 14. The pump assembly 32 may include both a drain pump 34 and a recirculation pump 36.
The drain pump 34 may draw liquid from the sump 26 and pump the liquid out of the dishwasher 10 to a household drain line 38. The recirculation pump 36 may draw liquid from the sump 26 and pump the liquid to the spraying system to supply liquid to any of the upper sprayer 40, mid-level rotatable sprayer 42, and lower rotatable sprayer 44. As illustrated, liquid may be supplied to the mid-level rotatable sprayer 42 and upper sprayer 40 through a supply tube 48 that extends generally rearwardly from the recirculation pump 36 and upwardly along a rear wall of the tub 14. While the supply tube 48 ultimately supplies liquid to the mid-level rotatable sprayer 42 and upper sprayer 40, it may fluidly communicate with one or more manifold tubes that directly transport liquid to the mid-level rotatable sprayer 42 and upper sprayer 40. A heating system having a heater 28 may be located within or near the sump 26 for heating liquid contained in the sump 26.
A controller 50 may also be included in the dishwasher 10, which may be operably coupled to various components of the dishwasher 10 to implement a cycle of operation. A control panel or user interface 52 provided on the dishwasher 10 and coupled to the controller 50 may be used to select a cycle of operation. The user interface 52 may include operational controls such as dials, lights, switches, and displays enabling a user to input commands to the controller 50 and receive information. Alternatively, the treating cycle may be automatically selected by the controller 50 based on soil levels sensed by the dishwasher 10 to optimize the performance of the dishwasher 10 for a particular load of utensils. The dishwasher 10 may further include other conventional components such as additional spray arms or nozzles, a filter, a treating chemistry dispenser, etc.; however, these components are not germane to the present invention and will not be described further herein.
FIG. 2 illustrates a partial perspective view of the lower rotatable sprayer 44, which has a housing 52 that includes a hub 53 from which multiple spray arms 54 extend. A liquid supply conduit 56 fluidly couples the hub 53 to the recirculation pump 36 such that liquid may be provided to the spray arms 54 through the hub 53. The hub 53 is rotatably mounted to the liquid supply conduit 56 such that the spray arms 54 and hub 53 are rotatable about an axis of rotation 58.
Nozzles, such as nozzles 60 and 66, may be provided on the spray arms 54 in any desired configuration. As illustrated, nozzles 60 and 66 provide different spray patterns and are provided on different spray arms 54, thereby, controlling the supply of liquid to the different spray arms 54 functions to control the spray pattern provided to the treating chamber 16. One or more of the nozzles 60 and 66 may be provided on their respective spray arm 54.
The first nozzle 60 emits a first spray pattern 62, which has been depicted as being a discrete, focused, and concentrated spray pattern. A first liquid conduit 64 is provided within an interior of the spray arm 54 and may extend from the first nozzle 60 to the hub 53 to fluidly couple the first nozzle 60 to the hub 53. The second nozzle 66 emits a second spray pattern 68, which is depicted as being different from the first spray pattern 62. More specifically, the second spray pattern 68 has been illustrated as a wide angle diffused spray pattern, which produces more of a shower as compared to the more concentrated and discrete spray pattern produced by the first nozzle 60. A second liquid conduit 70 may be provided within an interior of the spray arm 54 and may extend from the second nozzle 68 to the hub 53 to fluidly couple the second nozzle 68 to the hub 53. In one implementation, the first spray pattern may be a continuous stream of liquid and the second spray pattern may be multiple drops of liquid, which do not form a continuous stream.
The lower rotatable sprayer 44 is illustrated as having four spray arms 54. Two of the four spray arms 54 are illustrated as having the first liquid conduit 64, which is fluidly coupled with the first nozzle 60 provided while the remaining two spray arms 54 are illustrated as having the second liquid conduit 70, which is fluidly coupled with the second spray nozzles 66. It has also been contemplated that each spray arm 54 may have spray nozzles with totally different and distinct spray patterns. Although multiple spray nozzles have been illustrated on each arm, it has been contemplated that only one nozzle may be located on each arm. Further, it has been contemplated that any number of spray arms 54 may be included on the lower rotatable sprayer 44. By way of non-limiting example, the lower rotatable sprayer 44 may have as many as sixteen different arms to as few as two arms.
FIG. 3 illustrates a cross-sectional view of the lower rotatable sprayer 44 and illustrates that the hub 53 is cylindrical and has a peripheral wall with a closed top and an open bottom. The hub 53 includes multiple hollow male connectors 55 extending from the peripheral wall and each of the spray arms 54 may be mounted thereon. The openings within each of the male connectors 55 allow for fluid coupling between the hub 53 and the fluid conduits 64, 70 in the spray arms 54.
A control valve 74 may be provided within the hub 53 and includes a valve body 75 that is also rotatable about the axis of rotation 58. The valve body 75 has a circular sleeve configuration having a peripheral wall 78 with an upper edge defining an open top 79 and a lower edge defining an open bottom 80. The open bottom 80 forms an inlet 76, which is fluidly coupled to the liquid supply conduit 56. An opening in the peripheral wall 78 defines the outlet 77. The radial size of the outlet 77 may be such that the arc length of the peripheral wall 78 that it spans is less than a quarter of the arc length of the peripheral wall 78 such that only one of the spray arms 54 may be fluidly coupled to the hub 53 at a time. Alternatively, it has been contemplated that the size of the outlet 77 may be smaller or larger such that the arc length it spans may be smaller or larger, respectively.
The outlet 77 may be selectively coupled to any one of the spray arms 54 by the relative rotational positions of the housing 52 and the valve body 75. The outlet 77 may be sized according to the number of conduits in the housing 52 and is illustrated as being sized such that only one spray arm 54 is supplied liquid at a time. Alternatively, a larger outlet could be used in the valve body 75 or multiple outlets could be included in the valve body 75 such that liquid may be supplied to multiple conduits simultaneously.
A drive system 82 is provided to control the relative rotation between the control valve 74 and the hub 53, which provides for controlling where and the duration of when the valve body outlet opening 77 fluidly couples to one of the first and second conduits 64, 70 of one of the spray arms 54. While illustrated as coupling both the valve body and hub 53, the drive system 82 may be operably coupled to either the hub 53 or the valve body 75 to control the rotation of the hub 53 or the valve body 75, respectively, relative to the other.
The drive system 82 further comprises a gear train 83 that affects the operable coupling between the hub 53 and the valve body 75. The gear train 83 includes a first ring gear 84 provided on the hub 53 and a second ring gear 85 provided on the valve body. First, second and third idler gears 86, 87, 88 coupled the first and second ring gears 84, 85. The first idler gear 86 is illustrated as being directly enmeshed with the first ring gear 84 while the second idler gear 87 is illustrated as being enmeshed with the second ring gear 85. The third idler gear 88 is illustrated as being enmeshed with both the first idler gear 86 and the second idler gear 87. The idler gears 86-88 operably couple the first ring gear 84 with the second ring gear 85 such that the relative rotational positions of the hub 53 and valve body 75 may be controlled to selectively supply liquid from the liquid supply conduit 56 to one of the first and second nozzles 60, 66. Alternatively, the first, second, and third idler gears may be replaced by any number of gears including a single gear which may operably couple the first ring gear 84 with the second ring gear 85 such that the relative rotational positions of the hub 53 and valve body 75 may be controlled.
As illustrated, the first ring gear 84 and the second ring gear 85 are vertically spaced from each other. In turn, the first and second idler gears 86, 87 that are enmeshed with the first and second ring gears 84, 85, respectively, are also vertically spaced from each other. The third idler gear 88 spans the vertical space such that the third idler gear 88 enmeshes with both the first idler gear 86 and the second idler gear 87.
The open top 79 of the valve body 75 provides a space through which the idler gears may extend to couple the ring gears 84, 85 together. The valve body 75 is received with the hub 53 such that the closed top of the hub 53 fluidly closes the open top 79 of the valve body 75. The hub 53 essentially provides a sealing surface for the open top of the valve body 75. As illustrated, the gear train 83 is immersed within a liquid flow path of the lower rotatable sprayer 44. It has also been contemplated that the gear train 83 could be separated from the liquid by bringing the gear train 83 above the valve body 75, reducing the size of the open top 79 of the valve body 75, and sealing the open top 79.
The drive system 82 further comprises a spindle shaft 89 for supporting the idler gears 86-88. The spindle shaft 89 has three separate gear shafts 90, each of which couples to one of the idler gears 86-88. Each gear shaft 90 provides an axis about which each of the corresponding idler gears 86-88 may rotate and aids in supporting the idler gears 66-68. The spindle shaft 89 is illustrated as being operably coupled within a portion of the liquid supply conduit 56 such that the spindle shaft 89 is anchored to the liquid supply conduit 56. The anchoring of the spindle shaft 89 results in improved stability and reduced friction as well as reduced leakage of the control valve 74.
Any of the gears 84-88, illustrated in the drive system 82, may be a rotatable drive gear, which affects the relative rotation between the hub and the arms. The drive system 82 may be operated to control the relative rotation of the housing 52 and the valve body 75 and thus, control a spray of liquid emitted from one of the multiple arms 52 in pre-selected areas of the treating chamber 16. The drive system 82 may be powered in a variety of ways. For example, the drive system 82 may rely on liquid pumped from the recirculation pump 36 to provide hydraulic drive to rotate the hub 53, which through the gear train 83 affects the rotation of the valve body 75. Alternatively, it is contemplated that the drive system 82 may be motor-driven. For example, an electric motor may be provided externally of the tub and have a drive shaft that extends through the tub and couples to one of the gears of the drive train. It is contemplated that the drive shaft could extend through the supply conduit 56, up through the spindle 89 and drive the idler gear 87. Further, it has been contemplated that other drive systems may be used to control the relative rotation of the housing 52 and the valve body 75. The drive system 82 is merely an exemplary drive system and any suitable drive system may be used to control the relative rotation of the housing 52 and the valve body 75.
As illustrated in FIG. 4, the controller 50 may be coupled with the recirculation pump 36 for recirculation of liquid in the treating chamber 16 and the drain pump 34 for drainage of liquid from the dishwasher 10. The controller 50 may also be operably coupled with the heater 28 to heat the liquid within the wash tub 14 depending on the cycle of operation. The controller 50 may also receive inputs from one or more other additional sensors 91, examples of which are known in the art. Non-limiting examples of sensors that may be communicably coupled with the controller 50 include a temperature sensor and a turbidity sensor to determine the soil load associated with the utensils within the dishwasher 10. Further, if the drive system 82 is driven by an optional motor 92, then the controller 50 may be operably coupled to the motor 92 such that it may control the relative rotation of the housing 52 and the valve body 75 to control the spray emitted from the first and second nozzles 60, 66.
The controller 50 may be provided with a memory 94 and a central processing unit (CPU) 96. The memory 94 may be used for storing control software in the form of a plurality of executable instructions that may be executed by the CPU 96 in completing a cycle of operation of the dishwasher 10 and any additional software. For example, the memory 94 may store one or more pre-programmed cycles of operation that may be selected by a user. Examples of cycles of operation include normal, light/china, heavy/pots and pans, and rinse only.
In general, during operation of the dishwasher 10, the controller 50 may be operably coupled with one or more components of the dishwasher 10 for communicating with and controlling the operation of the component to complete a cycle of operation. During operation, liquid may be supplied from a liquid source such as a household water supply (not shown) and the recirculation pump 36 may be operated to supply liquid from the sump 26 to the sprayers 40, 42, 44 to spray utensils located in the treating chamber 16. Liquid may be selectively supplied from the liquid supply conduit 56 to any one of the first and second liquid conduits 64, 70 and thus, the first and second nozzles 60, 66 by controlling the relative rotation between the valve body 75 and the housing 52. More specifically, by controlling the relative rotation between the valve body 75 and the housing 52 the location of the outlet 77 relative to the multiple spray arms 54 may be controlled and thus the flow of liquid from the liquid supply conduit 56 to one of the first and second nozzles 60, 66 may be controlled.
If the drive system 82 is hydraulically driven, as illustrated above, the drive system 82 controls both the rotation of the housing 52 and the valve body 75. In the embodiment illustrated above, the first ring gear 84 is the drive gear. More specifically, when liquid reaches the housing 52 the rotatable spray arm 54, which is currently fluidly coupled to the liquid supply conduit 56, is hydraulically driven. As the spray arm 54 is hydraulically driven the hub 53 and thus the first ring gear 84 are also hydraulically driven and caused to rotate about the axis of rotation 58. As the ring gear 84 is rotated it affects the rotation of the second ring gear 85 through the gear train 83. This results in the rotation of the valve body 75 relative to the housing 52.
As the valve body 75 is rotated relative to the housing 52, a fluid path to each of the first and second nozzles 60, 66 is sequentially fluidly coupled and uncoupled as the lower rotatable sprayer 44 rotates. More specifically, as the valve body 75 is rotated relative to the housing 52, the outlet 77 is also rotated relative to the first and second conduits 64, 70. Thus, the valve body 75 will close the fluid path to one of the first and second conduits 64, 70 and open a fluid path to another of the first and second conduits 64, 70. This results in a sequential fluid coupling between each of the first and second conduits 64, 70 and the liquid supply conduit 56. The amount of time that the outlet 77 is fluidly coupled with each of the first and second conduits 64, 70 controls the duration of the time that each of the first and second nozzles 60, 66 spray liquid. The time of fluid coupling can be thought of as a dwell time. With the above described control valve 74, the dwell time can be controlled by the gear ratio and the flow rate of liquid. The rotation of the valve body 75 and the housing 52 ends when fluid is no longer pumped by the recirculation pump 36 to the lower rotatable sprayer 44 such that the lower rotatable sprayer 44 is no longer hydraulically driven.
Gear ratios of the gear train 83 may be selected to control the relative movement of the valve body 75 and housing 52. The gear ratio of the gear train 83 is a function of the ratios of gears forming the gear train. Thus, the gears may be selected to provide a desired ratio to provide a desired dwell time. If the relative speed between the valve body 75 and housing 52 is greater than zero, the fluid coupling to the multiple spray arms 54 will be sequenced. It has been contemplated that the gear ratio may be such that the valve body 75 rotates either slower or faster than the hub 53. As illustrated, the gear ratio is such that the dwell time may be for at least one complete revolution of the first ring gear 84. Alternatively, the gear ratio may be such that the dwell time may be for multiple revolutions of the first ring gear 84. Alternatively, it has been determined that the gear ratio may be such that the dwell time is only for a predetermined portion of one revolution of the first ring gear 84. Alternatively, it has been contemplated that the gear ratio may be such that the valve body 75 and one of the spray arms 54 may be fluidly coupled multiple times during one complete revolution of the first ring gear 84. If one wants to open up a different conduit to the fluid path for every one rotation of the housing 52, then the gear ratio should take into account the number of arms 52 that are on the housing 52. For example, the gear ratio would be different for a sprayer having two arms and a sprayer having four arms.
Alternatively, if the drive system 82 is motor operated (not illustrated), during operation of the dishwasher 10, either or both the housing 52 and the valve body 75 may be rotated by the motor 92 to control the flow of liquid to the first and second nozzles 60, 66 as the lower rotatable sprayer 44 rotates. If only the valve body 75 is driven by the motor it is contemplated that the hub 53 and the valve body 75 may be independently driven. More specifically, the hub 53 may be hydraulically driven while the valve body 75 may be motor driven. It should be noted that in such a motor operated drive system any of the gears may be the drive gear. Once the drive system 82 has been operated by the motor 92 to fluidly couple one of the first and second conduits 64, 70 with the liquid supply conduit 56 the controller 50 may turn off the motor and operate the recirculation pump 36 to supply liquid to the lower rotatable sprayer 44 through the liquid supply conduit 56. Alternatively, during the supply of liquid, the motor 92 may be operated such that the drive system 82 affects a sequencing of spray emitted from the first nozzle 60 and the second nozzle 66. In this manner, zonal washing, may be accomplished within the treating chamber 16 because the drive system 82 may have the ability to manipulate both the speed of rotation of the housing 52 and/or the speed of the rotation of the valve body 75 such that the controller 50 may control the sequence of spray emitted from the first nozzle 60 and the second nozzle 66 in pre-selected areas of the treating chamber 16.
The control valve 74, described above, allows for the selection of an active nozzle by turning the valve body 75 at a rate slower than that of the spray arm 54. If the rate of rotation of the valve body 75 and housing 52 is only slightly different, then each of the spray arms 52 will make multiple revolutions about the treating chamber 16 before the fluid path to the next spray arm 52 is connected. The configuration described above may allow for additional coverage of the treating chamber 16, as multiple types of spray nozzles having multiple spray patterns may be used during a cycle of operation, which in turn may result in better cleaning of utensils within the treating chamber 16 with no additional liquid consumption.
Further, because the lower rotatable sprayer 44 described above has multiple conduits and each conduit has a smaller total nozzle area than current spray arm designs, lower flow rates may be used and this may result in less liquid or water being required. This increases the velocity of the spray emitted from each of the first and second nozzles while not sacrificing coverage or individual nozzle size. Further, with less liquid flow needed, a smaller recirculation pump having a smaller motor may also be used which may result in a cost and energy savings.
FIG. 5 is a partial perspective view of a portion of an alternative rotatable sprayer 144 according to a second embodiment of the invention. The rotatable sprayer 144 is similar to the rotatable sprayer 44 previously described and, therefore, like parts will be identified with like numerals increased by 100, with it being understood that the description of the like parts of the rotatable sprayer 44 applies to the rotatable sprayer 144, unless otherwise noted.
One difference between the rotatable sprayer 44 and the rotatable sprayer 144 is that the rotatable sprayer 144 has been illustrated as including two separate arms 154 with each arm 154 including both a first nozzle 160 and a second nozzle 166. Further, a first liquid conduit 164 and a second liquid conduit 170 are both provided within the housing 152 on each arm 154. The first and second liquid conduits 164, 170 may extend from the first and second nozzles 160, 166, respectively, to the hub 153 to fluidly couple the first and second nozzles 160, 166 to the hub 153.
As with the earlier embodiment, a control valve 174 having a valve body 175 is included in the housing to control the flow of liquid to the first and second nozzles 160, 166. However, the valve body 175 has two outlets 177 such that either the first or second nozzles 160, 166 in both spray arms 154 may spray liquid at the same time. Thus, the valve body 175 may selectively supply liquid from the liquid supply conduit 156 to either the first or second liquid conduits 164, 170 within each spray arm 154 by controlling the relative rotation between the valve body 175 and the housing 152. A drive system (not shown) may be operably coupled to either or both the housing 152 and the valve body 175 to control the rotation of either or both the housing 152 and the valve body 175 to control the spray of liquid emitted from either of the first and second nozzles 160, 166. More specifically, such a drive system may control the location of the valve outlets 177 relative to the first or second liquid conduits 164, 170 within each spray arm 154.
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, and the scope of the appended claims should be construed as broadly as the prior art will permit. For example, it has been contemplated that a spray arm with a control valve and drive system may also be used in the mid-level rotatable spray arm or in the upper sprayer so long as the upper sprayer was rotatable.

Claims

1. An automatic dishwasher for treating utensils according to a cycle of operation, comprising:

a tub at least partially defining a treating chamber for receiving utensils for treatment;

a rotatable sprayer comprising:

a housing having a hub rotatable about an axis of rotation;

a first nozzle provided on the housing and having a first spray pattern;

a second nozzle provided on the housing and having a second spray pattern, different from the first spray pattern;

a first liquid conduit provided within the housing and extending from the first nozzle to the hub to fluidly couple the first nozzle to the hub;

a second liquid conduit provided within the housing and extending from the second nozzle to the hub to fluidly couple the second nozzle to the hub;

a liquid supply fluidly coupled to the hub; and

a control valve provided within the hub and comprising a valve body, rotatable about the axis of rotation, having an inlet and an outlet;

wherein the inlet is fluidly coupled to the liquid supply and the outlet is selectively fluidly coupled to either of the first and second liquid conduits by the relative rotational positions of the housing and the valve body, such that liquid from the liquid supply is selectively supplied to the first and second nozzles by controlling the relative rotation between the valve body and the housing.

2. The automatic dishwasher of claim 1 wherein the first spray pattern is more diffused than the second spray pattern.

3. The automatic dishwasher of claim 1 wherein the second spray pattern is more concentrated than the first spray pattern.

4. The automatic dishwasher of claim 1, further comprising multiple first and second nozzles on the housing.

5. The automatic dishwasher of claim 1 wherein the housing defines multiple arms extending from the hub.

6. The automatic dishwasher of claim 5 wherein the first and second nozzles are provided on the same arm.

7. The automatic dishwasher of claim 5 wherein the first and second nozzles are provided on different arms.

8. The automatic dishwasher of claim 7, further comprising a drive system operably coupled to at least one of the housing and the valve body to control the rotation of the at least one of the housing and the valve body relative to the other of the housing and the valve body.

9. The automatic dishwasher of claim 8 wherein the drive system is operably coupled to both the housing and the valve body to control the rotation of both the housing and the valve body.

10. The automatic dishwasher of claim 9 wherein the drive system controls the relative rotation of the housing and the valve body to control spray emitted from either the first and second nozzles in pre-selected areas of the treating chamber.

11. The automatic dishwasher of claim 9 wherein the drive system controls the relative rotation of the housing and the valve body to control a sequence of the spray emitted from the first and second nozzles in a pre-selected area of the treating chamber.

12. An automatic dishwasher for treating utensils according to a cycle of operation, comprising:

a rotatable sprayer comprising a hub rotating about an axis of rotation and an arm extending from the hub and having a nozzle provided on the arm and a liquid conduit provided within the arm and extending from the hub to the nozzle;

a liquid supply fluidly coupled to the hub;

a control valve provided within the hub and comprising a valve body, rotatable about the axis of rotation, having an inlet fluidly coupled to the liquid supply and an outlet selectively coupled to the liquid conduit based on the relative rotational positions of the valve body and the hub; and

a drive system comprising a gear train having a first ring gear provided on the hub, a second ring gear provided on the valve body, and at least one gear operably coupling the first and second ring gears;

wherein the gear train operably couples the hub and valve body to control the relative rotational positions of the hub and valve body to selectively supply liquid from the liquid supply to the nozzle.

13. The automatic dishwasher of claim 12 wherein the at least one gear comprises a first idler gear directly enmeshed with at least one of the first ring gear and the second ring gear.

14. The automatic dishwasher of claim 13 wherein the gear train further comprises a second idler gear enmeshed with at least one of the first idler gear and the other of the first ring gear and second ring gear.

15. The automatic dishwasher of claim 14 wherein the gear train further comprises a third idler gear that enmeshes with both the first idler gear and the second idler gear.

16. The automatic dishwasher of claim 15, wherein the first and second idler gears are vertically spaced.

17. The automatic dishwasher of claim 16, further comprising a spindle shaft having three separate gear shafts with each gear shaft coupled to one of the idler gears and providing an axis about which the corresponding idler gear may turn.

18. The automatic dishwasher of claim 12 wherein any of the gears in the gear train may be a drive gear.

19. The automatic dishwasher of claim 18 wherein the first ring gear is the drive gear.

20. The automatic dishwasher of claim 18, further comprising a motor operably coupled with the drive gear to control the rotation of the drive gear.

21. The automatic dishwasher of claim 12 wherein a gear ratio of the gear train is such that the hub and valve body rotate at different speeds.

22. The automatic dishwasher of claim 21 wherein the gear ratio is such that the valve body rotates slower than the hub.

23. The automatic dishwasher of claim 21 wherein the gear ratio is such that the valve body and arm remain fluidly coupled for at least one complete revolution.

24. The automatic dishwasher of claim 21 wherein the gear ratio is such that the valve body and arm remain fluidly coupled for a predetermined portion of one revolution of the first ring gear.

25. The automatic dishwasher of claim 24 wherein the gear ratio is such that the valve body and the arm are fluidly coupled multiple times during one complete revolution of the first ring gear.

26. The automatic dishwasher of claim 12 wherein the valve body comprises a sleeve having a peripheral wall with an upper edge defining an open top and a lower edge defining an open bottom, with the open bottom forming the inlet and an opening in the peripheral wall defining the outlet.

27. The automatic dishwasher of claim 26 wherein the hub comprises a cylinder having a peripheral wall with a closed top and an open bottom, with the valve body received with the hub such that the closed top of the hub fluidly closes the open top of the valve body.

28. The automatic dishwasher of claim 27 wherein the hub comprises an opening in the hub peripheral wall, which is fluidly coupled to the conduit in the arm.

29. The automatic dishwasher of claim 28 wherein the hub further comprises multiple openings in the hub peripheral wall, and further comprising multiple arms with nozzles, each of the arms having a conduit fluidly coupled to a corresponding one of the multiple openings.