Patent Application
20140317857
This disclosure relates generally to laundry treating appliances, and, more particularly, to laundry treating appliances and methods of controlling the same to balance small loads.
Laundry treating appliances, such as clothes washers, dryers, combination washer-dryers, refreshers, and non-aqueous systems, may have a configuration based on a rotating drum that defines a treating chamber in which laundry items are placed for treating. The laundry treating appliance may have a controller that implements a number of pre-programmed cycles of operation having one or more operating parameters. The controller may control a motor to rotate the drum according to one of the pre-programmed cycles of operation. The controller may control the motor to rotate the drum at the same speeds for a given pre-programmed cycle of operation regardless of the characteristics of the laundry items or changes in the system.
A disclosed example method of operating a laundry treating appliance having a rotating drum defining a treating chamber in which laundry is received for treatment according to at least one cycle of operation, and at least one balancing ring to counteract an imbalance of the rotating drum includes determining whether a small load is present in the treating chamber, substantially aligning the small load and a moveable mass of the balancing ring(s) when the drum is substantially stationary, and accelerating rotation of the drum based on a viscosity of fluid in the balancing ring(s) to position the small load substantially opposite the moveable mass.
Another disclosed example method of operating a laundry treating appliance having a rotating drum defining a treating chamber in which laundry is received for treatment according to at least one cycle of operation, and a balancing ring to counteract an imbalance of the rotating drum includes determining a position of a moveable mass of the balancing ring, and accelerating rotation of the drum based on a viscosity of fluid in the balancing ring, a location of a small load in the treating chamber, and the detected position to position the small load substantially opposite the moveable mass at and above a critical rotation speed of the drum.
A disclosed example laundry treating appliance includes a rotating drum defining a treating chamber in which laundry is received for treatment according to at least one cycle of operation, a balancing ring coupled with the rotating drum to counteract an imbalance of the rotating drum, and a controller configured to determine whether a small load is present in the treating chamber, substantially align the small load and a moveable mass of the balancing ring when the rotating drum is substantially stationary, and accelerate rotation of the drum based on an estimated temperature of fluid in the balancing ring to position the small load substantially opposite the moveable mass at and above a critical rotation speed of the drum.
When small loads of laundry (e.g., one item of clothing) are washed it may be difficult for a laundry treating appliance to sufficiently balance the load in order to reach the high speed of rotation necessary to extract fluid from the laundry to a desired extent. Such circumstances may result in a longer spin cycle and/or excessively wet clothes that require an extended drying time—both of which may lead to customer dissatisfaction. To improve fluid extraction performance, laundry treating appliances and methods of controlling the same to balance small loads are disclosed herein.
The laundry treating appliance of
The laundry holding system typically comprises a tub 14 supported within the cabinet 12 by a suitable suspension system and a drum 16 provided within the tub 14, the drum 16 defining at least a portion of a laundry treating chamber 18. The drum 16 may include a plurality of perforations 20 such that liquid may flow between the tub 14 and the drum 16 through the perforations 20. A plurality of baffles 22 may be disposed on an inner surface of the drum 16 to lift the laundry load received in the treating chamber 18 while the drum 16 rotates. It is also within the scope of this disclosure for the laundry holding system to not include the drum 16 such that the tub 14 defines the laundry treating chamber.
The laundry holding system may further include a door 24 that may be movably mounted to the cabinet 12 to selectively close both the tub 14 and the drum 16. A bellows 26 may couple an open face of the tub 14 with the cabinet 12, with the door 24 sealing against the bellows 26 when the door 24 closes the tub 14.
The washing machine 10 may further include a suspension system 28 for dynamically suspending the laundry holding system within the structural support system.
The washing machine 10 may also include at least one balancing ring 38 containing a balancing material (i.e., mass) moveable within the balancing ring 38 to counterbalance an imbalance that may be caused by laundry in the treating chamber 18 during rotation of the drum 16. The balancing material may be in the form of metal balls or any other readily moveable mass, fluid, or a combination thereof. For example, the balancing ring 38 may be a ball balancing ring comprises a plurality of metal balls suspended in a viscous fluid. The balancing ring 38 may extend circumferentially around a periphery of the drum 16 and may be located at any desired location along an axis of rotation of the drum 16. When multiple balancing rings 38 are present, they may be spaced along the axis of rotation of the drum 16. For example, the balancing rings 38 may be equally and/or symmetrically spaced.
The washing machine 10 may further include a liquid supply system for supplying water to the washing machine 10 for use in treating laundry during a cycle of operation. The liquid supply system may include a source of water, such as a household water supply 40, which may include separate valves 42 and 44 for controlling the flow of hot and cold water, respectively. Water may be supplied through an inlet conduit 46 directly to the tub 14 by controlling first and second diverter mechanisms 48 and 50, respectively. The diverter mechanisms 48, 50 may be a diverter valve having two outlets such that the diverter mechanisms 48, 50 may selectively direct a flow of liquid to one or both of two flow paths. Water from the household water supply 40 may flow through the inlet conduit 46 to the first diverter mechanism 48, which may direct the flow of liquid to a supply conduit 52. The second diverter mechanism 50 on the supply conduit 52 may direct the flow of liquid to a tub outlet conduit 54, which may be provided with a spray nozzle 56 configured to spray the flow of liquid into the tub 14. In this manner, water from the household water supply 40 may be supplied directly to the tub 14.
The washing machine 10 may also be provided with a dispensing system for dispensing treating chemistry to the treating chamber 18 for use in treating the laundry according to a cycle of operation. The dispensing system may include a dispenser 62, which may be a single use dispenser, a bulk dispenser or a combination of a single and bulk dispenser. Non-limiting examples of suitable dispensers are disclosed in U.S. Pub. No. 2010/0000022 to Hendrickson et al., filed Jul. 1, 2008, entitled “Household Cleaning Appliance with a Dispensing System Operable Between a Single Use Dispensing System and a Bulk Dispensing System,” U.S. Pub. No. 2010/0000024 to Hendrickson et al., filed Jul. 1, 2008, entitled “Apparatus and Method for Controlling Laundering Cycle by Sensing Wash Aid Concentration,” U.S. Pub. No. 2010/0000573 to Hendrickson et al., filed Jul. 1, 2008, entitled “Apparatus and Method for Controlling Concentration of Wash Aid in Wash Liquid,” U.S. Pub. No. 2010/0000581 to Doyle et al., filed Jul. 1, 2008, entitled “Water Flow Paths in a Household Cleaning Appliance with Single Use and Bulk Dispensing,” U.S. Pub. No. 2010/0000264 to Luckman et al., filed Jul. 1, 2008, entitled “Method for Converting a Household Cleaning Appliance with a Non-Bulk Dispensing System to a Household Cleaning Appliance with a Bulk Dispensing System,” U.S. Pub. No. 2010/0000586 to Hendrickson, filed Jun. 23, 2009, entitled “Household Cleaning Appliance with a Single Water Flow Path for Both Non-Bulk and Bulk Dispensing,” and application Ser. No. 13/093,132, filed Apr. 25, 2011, entitled “Method and Apparatus for Dispensing Treating Chemistry in a Laundry Treating Appliance,” which are herein incorporated by reference in full.
Regardless of the type of dispenser used, the dispenser 62 may be configured to dispense a treating chemistry directly to the tub 14 or mixed with water from the liquid supply system through a dispensing outlet conduit 64. The dispensing outlet conduit 64 may include a dispensing nozzle 66 configured to dispense the treating chemistry into the tub 14 in a desired pattern and under a desired amount of pressure. For example, the dispensing nozzle 66 may be configured to dispense a flow or stream of treating chemistry into the tub 14 by gravity, i.e. a non-pressurized stream. Water may be supplied to the dispenser 62 from the supply conduit 52 by directing the diverter mechanism 50 to direct the flow of water to a dispensing supply conduit 68.
Non-limiting examples of treating chemistries that may be dispensed by the dispensing system during a cycle of operation include one or more of the following: water, enzymes, fragrances, stiffness/sizing agents, wrinkle releasers/reducers, softeners, antistatic or electrostatic agents, stain repellants, water repellants, energy reduction/extraction aids, antibacterial agents, medicinal agents, vitamins, moisturizers, shrinkage inhibitors, and color fidelity agents, and combinations thereof.
The washing machine 10 may also include a recirculation and drain system for recirculating liquid within the laundry holding system and draining liquid from the washing machine 10. Liquid supplied to the tub 14 through tub outlet conduit 54 and/or the dispensing supply conduit 68 typically enters a space between the tub 14 and the drum 16 and may flow by gravity to a sump 70 formed in part by a lower portion of the tub 14. The sump 70 may also be formed by a sump conduit 72 that may fluidly couple the lower portion of the tub 14 to a pump 74. The pump 74 may direct liquid to a drain conduit 76, which may drain the liquid from the washing machine 10, or to a recirculation conduit 78, which may terminate at a recirculation inlet 80. The recirculation inlet 80 may direct the liquid from the recirculation conduit 78 into the drum 16. The recirculation inlet 80 may introduce the liquid into the drum 16 in any suitable manner, such as by spraying, dripping, or providing a steady flow of liquid. In this manner, liquid provided to the tub 14, with or without treating chemistry may be recirculated into the treating chamber 18 for treating the laundry within.
The liquid supply and/or recirculation and drain system may be provided with a heating system that may include one or more devices for heating laundry and/or liquid supplied to the tub 14, such as a steam generator 82 and/or a sump heater 84. Liquid from the household water supply 40 may be provided to the steam generator 82 through the inlet conduit 46 by controlling the first diverter mechanism 48 to direct the flow of liquid to a steam supply conduit 86. Steam generated by the steam generator 82 may be supplied to the tub 14 through a steam outlet conduit 87. The steam generator 82 may be any suitable type of steam generator such as a flow through steam generator or a tank-type steam generator. Alternatively, the sump heater 84 may be used to generate steam in place of or in addition to the steam generator 82. In addition or alternatively to generating steam, the steam generator 82 and/or sump heater 84 may be used to heat the laundry and/or liquid within the tub 14 as part of a cycle of operation.
Additionally, the liquid supply and recirculation and drain system may differ from the configuration shown in
The washing machine 10 also includes a drive system for rotating the drum 16 within the tub 14. The drive system may include a motor 88, which may be directly coupled with the drum 16 through a drive shaft 90 to rotate the drum 14 about a rotational axis during a cycle of operation. The motor 88 may be a brushless permanent magnet (BPM) motor having a stator 92 and a rotor 94. Alternately, the motor 88 may be coupled to the drum 16 through a belt and a drive shaft to rotate the drum 16, as is known in the art. Other motors, such as an induction motor or a permanent split capacitor (PSC) motor, may also be used. The motor 88 may rotate the drum 16 at various speeds in either rotational direction.
The washing machine 10 also includes a control system for controlling the operation of the washing machine 10 to implement one or more cycles of operation. The control system may include a controller 96 located within the cabinet 12 and a user interface 98 that is operably coupled with the controller 96. The user interface 98 may include one or more knobs, dials, switches, displays, touch screens and the like for communicating with the user, such as to receive input and provide output. The user may enter different types of information including, without limitation, cycle selection and cycle parameters, such as cycle options.
The controller 96 may include the machine controller and any additional controllers provided for controlling any of the components of the washing machine 10. For example, the controller 96 may include the machine controller and a motor controller. Many known types of controllers may be used for the controller 96. The specific type of controller is not germane to this disclosure. It is contemplated that the controller is a microprocessor-based controller that implements control software and sends/receives one or more electrical signals to/from each of the various working components to affect the control software. As an example, proportional control (P), proportional integral control (PI), and proportional derivative control (PD), or a combination thereof, a proportional integral derivative control (PID control), may be used to control the various components.
As illustrated in
The controller 96 may be operably coupled with one or more components of the washing machine 10 for communicating with and controlling the operation of the component to complete a cycle of operation. For example, the controller 96 may be operably coupled with the motor 88, the pump 74, the dispenser 62, the steam generator 82 and the sump heater 84 to control the operation of these and other components to implement one or more of the cycles of operation.
The controller 96 may also be coupled with one or more sensors 104 provided in one or more of the systems of the washing machine 10 to receive input from the sensors, which are known in the art and not shown for simplicity. Non-limiting examples of sensors 104 that may be communicably coupled with the controller 96 include: a treating chamber temperature sensor, a moisture sensor, a weight sensor, a chemical sensor, a position sensor, a load position sensor, a balancing ring ball position sensor, a motor temperature sensor, and a motor torque sensor, which may be used to determine a variety of system and laundry characteristics, such as balancing ring 38 temperature, balancing ring mass position(s), load position and/or laundry load inertia or mass.
In one example, one or more load amount sensors 106 may also be included in the washing machine 10 and may be positioned in any suitable location for detecting the amount of laundry, either quantitative (inertia, mass, weight, etc.) or qualitative (small, medium, large, etc.) within the treating chamber 18. By way of non-limiting example, it is contemplated that the amount of laundry in the treating chamber may be determined based on the weight of the laundry and/or the volume of laundry in the treating chamber. Thus, the one or more load amount sensors 106 may output a signal indicative of either the weight of the laundry load in the treating chamber 18 or the volume of the laundry load in the treating chamber 18. As used herein, a small load is defined to be an amount of laundry that can be balanced by the moveable mass of the balancing ring 38 without needing to distribute the laundry in the drum 16, taking into consideration the amount of imbalance that can be compensated by the suspension system 28 of the washing machine 10. For example, if the suspension system 28 can accommodate a 1 kilogram (kg) imbalance and the moveable mass of the balancing ring 38 is 0.7 kg, then a small load is an amount of laundry that weighs less than 1.7 kg. In some examples, a small load is a load having a weight or volume equal to or less than a threshold that represents the equivalent of 1 or 2 towels. As used herein, “determining” means any manner, direct or indirect, by any actor, human or machine, by which a parameter or condition may be decided, which includes, without limitation sensing, calculating, estimating, experimenting, empirically, theoretically, mathematically, identifying, detecting, computing, measuring, reading an output of a sensor, and reading a sensor output from a memory.
The one or more load amount sensors 106 may be any suitable type of sensor capable of determining the weight or volume of laundry in the treating chamber 18. Non-limiting examples of load amount sensors 106 for determining the weight of the laundry may include load volume, pressure, or force transducers that may include, for example, load cells and strain gauges. It has been contemplated that the one or more such sensors 106 may be operably coupled to the suspension system 28 to determine the weight borne by the suspension system 28. The weight borne by the suspension system 28 correlates to the weight of the laundry loaded into the treating chamber 18 such that the sensor 106 may indicate the weight of the laundry loaded in the treating chamber 18. In the case of a suitable sensor 106 for determining volume it is contemplated that an IR or optical based sensor may be used to determine the volume of laundry located in the treating chamber 18.
Alternatively, it has been contemplated that the washing machine 10 may have one or more pairs of feet 108 extending from the cabinet 12 and supporting the cabinet 12 on the floor and that a weight sensor (not shown) may be operably coupled to at least one of the feet 108 to sense the weight borne by that foot 108, which correlates to the weight of the laundry loaded into the treating chamber 18. In another example, the amount of laundry within the treating chamber 18 may be determined based on motor sensor output, such as output from a motor torque sensor. The motor torque is a function of the inertia of the rotating drum and laundry. There are many known methods for determining the load inertia, and thus the load mass, based on the motor torque. It will be understood that the details of the load amount sensors are not germane to this disclosure as any suitable method and sensors may be used to determine the amount of laundry.
As described in more detail below, the washing machine 10 may be controlled to substantially balance the drum 16 during high-speed spinning of small loads of laundry to remove fluid from the laundry. In particular, the drum 16 may be accelerated according to a particular ramp profile that results in the moveable mass of the balancing ring 38 being substantially opposite a small load when the drum 16 rotates at or through its critical rotation speed(s). As used herein, a critical rotation speed of the drum 16 corresponds to the natural resonant frequency of the suspension system 28, that is, the rotation speed of the drum 16 at which an imbalance of the drum 16 is likely to result in substantial, significant and/or unacceptable movement of the drum 16. In general, the suspension critical frequencies depend on the mass of the suspended assembly and the characteristics of the suspension system 28. The suspended assembly may have more than one natural frequency corresponding to side-to-side, up-down, and front-to-back movement of the drum 16. Example critical speeds for a horizontal-axis washing machine are 70-180 revolutions-per-minute (rpm) side-to-side, 160-250 rpm up-down, and 70-140 rpm front-to-back.
Referring now to
The method of
If a small load is present in the drum 16 (block 305), the controller 96 positions the drum 16 such that the small load is positioned at the bottom of the drum 16 (block 310). The controller 96 determines the temperature of the fluid in the balancing ring 38 using, for example, any or all of the example methods of
Based on the determined viscosity, the controller 96 selects a drum acceleration ramp profile (block 325). In some examples, the controller 96 selects the drum acceleration ramp profile from a table of ramp profiles according to the viscosity. That is, the memory 100 may store a plurality of ramp profiles for respective ones of a plurality of fluid viscosities. In some examples, the plurality of ramp profiles are determined empirically based on laboratory experiments. In other examples, the plurality of ramp profiles are mathematically derived based on the theoretical movement of the moveable mass in the viscous fluid. Example ramp profiles for a plurality of viscosities are illustrated in
Returning to
Returning to block 305, if a small load is not detected or indicated (block 305), the controller 96 performs normal drum acceleration (block 340) and control exits from the example method of
Alternatively, rather than initially aligning the moveable mass of the balancing ring 38 and the small load, the position(s) of the moveable mass (e.g., balls) of the balancing ring 38 and the small load may be determined. Then a ramp profile may be selected based on the fluid viscosity and the difference in position between the small load and the moveable mass, thus, obviating the need to wait for the small load and the moveable mass to become substantially aligned.
The method of
The method of
A processor, a controller and/or any other suitable processing device such as the example CPU 102 may be used, configured and/or programmed to execute and/or carry out the example methods of
As used herein, the term “tangible computer-readable medium” is expressly defined to include any type of computer-readable medium and to expressly exclude propagating signals. As used herein, the term “non-transitory computer-readable medium” is expressly defined to include any type of computer-readable medium and to exclude propagating signals. Example tangible and/or non-transitory computer-readable medium include a volatile and/or non-volatile memory, a volatile and/or non-volatile memory device, a flash memory, a read-only memory (ROM), a random-access memory (RAM), a programmable ROM (PROM), an electronically-programmable ROM (EPROM), and/or an electronically-erasable PROM (EEPROM).
To the extent not already described, the different features and structures of the various embodiments may be used in combination with each other as desired. That one feature may not be illustrated in all of the embodiments is not meant to be construed that it cannot be, but is done for brevity of description. Thus, the various features of the different embodiments may be mixed and matched as desired to form new embodiments, whether or not the new embodiments are expressly described.
Although certain example methods, apparatus and articles of manufacture have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the claims of this patent.
