Patent Application
20140096568
Laundry treating appliances typically include a clothes mover, such as an agitator or impeller, that imparts movement to the laundry load, whether indirectly through movement of the water, as with an agitator, or by direct contact between the laundry load and the clothes mover, such as for an impeller. When the clothes mover is an impeller, the treating of the laundry may be accomplished with less water because the amount of water needed to impart movement to the laundry load is less than that required for use with an agitator. However, distribution of the laundry load above the impeller may affect the movement of laundry and, thus, treating of the laundry load.
A laundry treating appliance configured to treat a laundry load according to a cycle of operation with a low level of treating liquid according to one embodiment of the invention may comprise a drum at least partially defining a treating chamber and having an open top and a longitudinal axis and an impeller mounted within the drum for reciprocal rotation about an axis generally coincident with the longitudinal axis of the drum. The impeller may include a raised center, a bottom plate located below the raised center and extending radially outwardly from the raised center and terminating in an outer periphery, a transition region between the bottom plate and the raised center, a center post extending upward from the raised center, and a plurality of radial protrusions extending along the raised center, the bottom plate, and the transition region, each protrusion having an upper section projecting generally perpendicular from the raised center and the transition region, and a lower section projecting upward from the bottom plate, with the lower section increasing in width toward the outer periphery. The protrusions and the bottom plate may be configured such that during the cycle of operation, when the level of the treating liquid does not exceed the height of the bottom plate, the reciprocal rotation of the impeller generates a frictional interaction between the laundry items and the protrusions to drag the laundry in contact with the protrusions radially inward toward the raised center and induce an inverse toroidal movement of the laundry.
In the drawings:
Automatic clothes washers may typically comprise a perforated basket or drum for holding a laundry load, which may include garments, sheets, towels, and other fabric items, and an imperforate tub containing a wash liquid comprising water or a mixture of water and detergent. A clothes mover may be coaxially mounted in the bottom of the drum and adapted for angular oscillation in order to agitate the laundry load. In one configuration, the drum, the clothes mover, and the tub may be oriented about a vertical axis.
Traditionally, a vertical axis clothes mover may be configured as an impeller or an agitator. The impeller is typically a low-profile base element having a circular periphery, with protrusions extending from the base element. The agitator typically has a base, which may be in combination with an auger that extends along the vertical axis approximately the height of the tub.
It is generally understood that a deep fill wash cycle, typically associated with an agitator, refers to a cloth to water ratio that, when combined with the action of the clothes mover, produces fluid motion which significantly aids in the motion of the clothes even if the actual water level in the machine is not near the top of the wash basket. The garments are considered suspended in the free fluid, or submerged, when there is sufficient fluid power to directly result in movement of the garments. The combination of the agitator contacting the laundry, the water moving through the laundry, and the relative contact between the laundry items imparts mechanical energy to the laundry for cleaning. The agitator can impart a significant mechanical force to the laundry, which is tempered with the water from the deep fill as most of the mechanical energy from the motion of the agitator goes to moving the water.
Likewise, a low fill wash cycle, also called a low water wash cycle and typically associated with an impeller, generally refers to a cloth to water ratio that, when combined with the action of the clothes mover, produces insufficient fluid motion to directly result in cloth motion regardless of the direction of fluid motion. In fact, the resulting cloth motion may still be present even if very little free fluid is present. In this process, a garment is not considered to be suspended or submerged in the free fluid even if the actual water level is near the top of the drum or near the top of the clothes load. The mechanical energy for cleaning the laundry in the low water wash comes from the interaction between the fabric items, and the fabric-on-fabric interaction tends to be less harsh on the fabric compared to the manner in which mechanical energy is imparted to the laundry in deep fill wash cycles. Additionally, because the low water wash cycle does not rely on the motion of the fluid and suspension of the garments in the fluid, washing machines with an impeller and corresponding low water wash cycles use less water and are more energy efficient than washing machines with an agitator and corresponding deep fill wash cycles.
In a vertical axis clothes washer with a deep fill wash cycle where the clothes are completely submerged, reciprocal movement of an agitator moves the garments along a toroidal, or donut-shaped, path extending radially inwardly toward the center of the drum, downwardly along the vertical axis, radially outwardly toward the outer wall of the drum, and upwardly along the perimeter of the drum where they repeat the cycle. One full cycle along this path is commonly referred to as a “rollover.”
In a low water cycle, such as where the clothes are wetted but not submerged, the movement of the clothes by reciprocating the impeller moves the garments in an opposite direction than that of the agitator with a deep fill in what has been termed an “inverse toroidal rollover.” The inverse toroidal rollover typically moves the laundry load along a path extending radially outwardly toward the outer wall of the drum, downwardly along the perimeter of the drum, radially inwardly toward the center of the drum, and upwardly along the vertical axis where they repeat the cycle.
The present invention is directed to an impeller for use with a low water cycle in a laundry treating appliance.
The laundry treating appliance of
The illustrated exemplary washing machine 10 may include a watertight tub 14 installed in the cabinet 12. A perforated drum 16 may be mounted in the tub 14 for rotation about a central, vertical axis of rotation 18 extending through the center of a vertical axis clothes mover in the form of an impeller 20, which will be described in further detail below. A drive motor 22 operating a transmission 24 through a drive belt 26 may be utilized to rotate the drum 16 and oscillate the impeller 20. The impeller 20 may be positioned above the floor of the drum 16 and rotated by a drive shaft 28 extending through an opening in the floor of the drum 16. The illustrated drive system for the drum 16 and the impeller 20 is provided for exemplary purposes only and is not limited to that shown in the drawings and described above; the particular drive system is not germane to the invention. The washing machine 10 may be fluidly connected to a water supply 30 through a valve assembly 32 which may be operated to selectively deliver water to the tub 14 through an outlet 34 that may be positioned at one side of the tub 14. The illustrated water supply system for the washing machine 10 is provided for exemplary purposes only and is not limited to that shown in the drawings and described above; the particular water supply system is not germane to the invention. A control panel 36 enables the operator to control the operation of the washing machine 10.
Referring now to
Referring again to
Referring again to
The front walls 62, 76 of the protrusions 50 and the secondary protrusions 70 may be spaced a distance from the outer periphery 46, as illustrated in the figures, or, alternatively, may be coincident with the outer periphery 46. When the front walls 62, 76 are spaced from the outer periphery 46, the spacing may be any suitable distance.
Referring again to
As another option, the center post 80 may include one or more vanes 86 extending radially from the center post 80. The vanes 86 may be connected to the center post 80 at a root 88 and terminate at an outer edge 90. While the vanes 86 may have any suitable configuration, the vanes 86 in the illustrated embodiment are circumferentially spaced and extend longitudinally along the center post 80 with a straight, vertical outer edge 90. At least some of the vanes 86 may be longitudinally aligned with the protrusions 50, if desired. The radial extent of the illustrated vanes 86 may be such that the outer edge 90 is coincident with the outer diameter of the raised center 40. Further, the vanes 86 may have any desired height and are shown as having a height greater than or equal to the constant diameter portion of the center post 80. As shown in
Referring now to
During operation of the washing machine 10 with the impeller 20, the treating liquid, such as water combined with a treating agent and hereinafter referred to as water, may be provided to the tub 14 and the drum 16, resulting in a water level suitable for a desired treating cycle of operation. For a cycle of operation with a low level of water, which is typically employed with clothes movers in the form of impellers, the water may be supplied to the drum 16 up to a maximum water level 96 that does not exceed the height of the bottom plate 42. The maximum water level 96 for a low water wash may differ from that shown in
Typically, when a laundry load is placed in a drum having a low-profile impeller, the laundry items naturally form multiple, generally horizontal layers, and each laundry item tends to spread out into a thin layer as it is placed in the drum 16. This produces a load that is interlayered with the layers extending over the center of the drum 16 and the impeller, especially when the laundry load includes large items, such as sheets, blankets, and towels. Laundry items spread out to cover the center of the impeller impede the inverse toroidal rollover necessary for proper treatment of the laundry load. However, the center post 80 of the impeller 20 prevents placement and migration of laundry items over the center of the impeller 20. When a user loads the laundry into the drum 16, the user must place the laundry items between the center post 80 and the side wall of the drum 16. Further, during operation, the laundry items moved radially inward along the bottom plate 42 must move upward when reaching the raised center 40 and the center post 80 and cannot migrate over the center of the impeller 20. Therefore, the combination of the impeller protrusions 50 and the center post 80 effects the desired inverse toroidal rollover of the laundry load.
As mentioned above, the vanes 86 may have any suitable configuration, and another embodiment of an impeller 120 having alternative vanes 186 is illustrated in
Further, the center post 80 need not have any of the vanes 86, as demonstrated by another embodiment of an impeller 220 depicted 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, and the scope of the appended claims should be construed as broadly as the prior art will permit.
