Patent Application
20240110321
The present subject matter relates generally to operation of a drain pump in washing machine appliances.
Washing machine appliances generally include a wash tub for containing water or wash fluid (e.g., water, detergent, bleach, or other wash additives). A basket is rotatably mounted within the wash tub and defines a wash chamber for receipt of articles for washing. During normal operation of such washing machine appliances, the wash fluid is directed into the wash tub and onto articles within the wash chamber of the basket. The basket or an agitation element can rotate at various speeds to agitate articles within the wash chamber, to wring wash fluid from articles within the wash chamber, etc.
Washing machine appliances can operate in numerous cycles. For example, the typical washing machine appliance may be operable in various wash cycles, rinse cycles, drain cycles, and spin cycles. In the wash cycle, the wash fluid is directed into the wash tub and onto articles within the wash chamber of the basket. The rinse cycle includes rinsing the articles in the wash tub, e.g., with fresh water. The drain cycle is used in between different cycles to drain the wash fluid out of the wash tub. In each of the cycles, fluid may be present in the tub of the washing machine appliance, and proper operation of the washing machine may rely upon knowing how much fluid, if any, is in the tub.
Aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention.
In one example embodiment, a washing machine appliance includes a cabinet, a wash tub positioned within the cabinet, and a wash basket rotatably mounted within the wash tub. The wash basket is accessible through an opening in the cabinet. A pump is configured to remove fluid from the wash tub, and a pressure sensor is disposed at the wash tub. A turbidity sensor, a conductivity sensor, and a temperature sensor are disposed in the cabinet, and a controller is in signal communication with the pressure sensor, the turbidity sensor, the conductivity sensor and the temperature sensor. The controller is configured to monitor the pressure measurement of the pressure sensor and record an ambient temperature measurement in response to the pressure measurement stabilizing. Activate the pump and a timer in response to a drain cycle starting. The controller is also configured to record a turbidity measurement from the turbidity sensor, a conductivity measurement from the conductivity sensor, and a temperature measurement from the temperature sensor and compare the turbidity measurement to a reference turbidity value, the conductivity measurement to a reference conductivity value, and the temperature measurement to the ambient temperature measurement. Then determine either a presence or an absence of fluid in the wash tub based at least in part on the turbidity measurement, the conductivity measurement, and the temperature measurement, and deactivate the pump in response to either the timer expiring or the determination of the absence of fluid in the wash tub.
In another example embodiment, a method of operating a washing machine appliance. The washing machine appliance includes a cabinet, a wash tub positioned within the cabinet, and a wash basket rotatably mounted within the wash tub. The wash basket is accessible through an opening in the cabinet. A pump is configured to remove fluid from the wash tub, and a pressure sensor is disposed at the wash tub. A turbidity sensor, a conductivity sensor, and a temperature sensor are disposed in the cabinet, and a controller is in signal communication with the pressure sensor, the turbidity sensor, the conductivity sensor and the temperature sensor. The method includes monitoring, by the controller, the pressure measurement of the pressure sensor and recording, at the controller, an ambient temperature measurement in response to the pressure measurement stabilizing. Then activating, by the controller, the pump and a timer in response to a drain cycle starting, and recording, at the controller, a turbidity measurement from the turbidity sensor, a conductivity measurement from the conductivity sensor, and a temperature measurement from the temperature sensor. Then comparing, by the controller, the turbidity measurement to a reference turbidity value, the conductivity measurement to a reference conductivity value, and the temperature measurement to the ambient temperature measurement, and determining, by the controller, either a presence or an absence of fluid in the wash tub based at least in part on the turbidity measurement, the conductivity measurement, and the temperature measurement. Then, deactivating, by the controller, the pump in response to either the timer expiring or the determination of the absence of fluid in the wash tub.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures.
Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention.
Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
As used herein, the term “or” is generally intended to be inclusive (i.e., “A or B” is intended to mean “A or B or both”). The phrase “in one embodiment,” does not necessarily refer to the same embodiment, although it may. The terms “first,” “second,” and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components. The terms “upstream” and “downstream” refer to the relative flow direction with respect to fluid flow in a fluid pathway. For example, “upstream” refers to the flow direction from which the fluid flows, and “downstream” refers to the flow direction to which the fluid flows.
Turning now to the figures,
Control panel 58 and input selectors 60 collectively form a user interface input for operator selection of machine cycles and features, and in one example embodiment, a display 61 indicates selected features, a countdown timer, or other items of interest to machine users. It should be appreciated, however, that in other example embodiments, the control panel 58, input selectors 60, and display 61, may have any other suitable configuration. For example, in other example embodiments, one or more of the input selectors 60 may be configured as manual “push-button” input selectors, or alternatively may be configured as a touchscreen (e.g., on display 61).
A lid 62 may be mounted to cover 54 and rotatable between an open position (not shown) facilitating access to a tub, also referred to as a wash tub, 64 located within cabinet 52 and a closed position (
As may be seen in
A nozzle 72 is configured for flowing a liquid into tub 64. In particular, nozzle 72 may be positioned at or adjacent to top portion 82 of basket 70. Nozzle 72 may be in fluid communication with one or more water sources 76, 77 in order to direct liquid (e.g., water) into tub 64 or onto articles within chamber 73 of basket 70. Nozzle 72 may further include apertures 88 through which water may be sprayed into the tub 64. Apertures 88 may, for example, be tubes extending from the nozzles 72 as illustrated, or simply holes defined in the nozzles 72 or any other suitable openings through which water may be sprayed. Nozzle 72 may additionally include other openings, holes, etc. (not shown) through which water may be flowed (i.e., sprayed or poured) into the tub 64.
Various valves may regulate the flow of fluid through nozzle 72. For example, a flow regulator may be provided to control a flow of hot or cold water into the wash chamber of washing machine appliance 50. For the example embodiment depicted, the flow regulator includes a hot water valve 74 and a cold water valve 75. The hot and cold water valves 74, 75 are used to flow hot water and cold water, respectively, therethrough. Each valve 74, 75 can selectively adjust to a closed position in order to terminate or obstruct the flow of fluid therethrough to nozzle 72. The hot water valve 74 may be in fluid communication with a hot water source 76, which may be external to the washing machine appliance 50. The cold water valve 75 may be in fluid communication with a cold water source 77, which may be external to the washing machine appliance 50. The cold water source 77 may, for example, be a commercial water supply, while the hot water source 76 may be, for example, a water heater. Such water sources 76, 77 may supply water to the appliance 50 through the respective valves 74, 75. A hot water conduit 78 and a cold water conduit 79 may supply hot and cold water, respectively, from the sources 76, 77 through the respective valves 74, 75 and to the nozzle 72.
An additive dispenser 84 may additionally be provided for directing a wash additive, such as detergent, bleach, liquid fabric softener, etc., into the tub 64. For example, dispenser 84 may be in fluid communication with nozzle 72 such that water flowing through nozzle 72 flows through dispenser 84, mixing with wash additive at a desired time during operation to form a liquid or wash fluid, before being flowed into tub 64. For the example embodiment depicted, nozzle 72 is a separate downstream component from dispenser 84. In other example embodiments, however, nozzle 72 and dispenser 84 may be integral, with a portion of dispenser 84 serving as the nozzle 72, or alternatively dispenser 84 may be in fluid communication with only one of hot water valve 74 or cold water valve 75. In still other example embodiments, the washing machine appliance 50 may not include a dispenser, in which case a user may add one or more wash additives directly to wash chamber 73. A pump assembly 90 (shown schematically in
An agitation element 92 may be oriented to rotate about the rotation axis A (e.g., parallel to the vertical direction V). Generally, agitation element 92 includes an impeller base 120 and extended post 130. The agitation element 92 depicted is positioned within the basket 70 to impart motion to the articles and liquid in the chamber 73 of the basket 70. More particularly, the agitation element 92 depicted is provided to impart downward motion of the articles along the rotation axis A. For example, with such a configuration, during operation of the agitation element 92 the articles may be moved downwardly along the rotation axis A at a center of the basket 70, outwardly from the center of basket 70 at the bottom portion 80 of the basket 70, then upwardly along the rotation axis A towards the top portion 82 of the basket 70.
In optional example embodiments, basket 70 and agitation element 92 are both driven by a motor 94. Motor 94 may, for example, be a pancake motor, direct drive brushless motor, induction motor, or other motor suitable for driving basket 70 and agitation element 92. As motor output shaft 98 is rotated, basket 70 and agitation element 92 are operated for rotatable movement within tub 64 (e.g., about rotation axis A). Washing machine appliance 50 may also include a brake assembly (not shown) selectively applied or released for respectively maintaining basket 70 in a stationary position within tub 64 or for allowing basket 70 to spin within tub 64.
Various sensors may additionally be included in the washing machine appliance 50. For example, a pressure sensor 110 may be positioned in the tub 64 as illustrated or, alternatively, may be remotely mounted in another location within the appliance 50 and be operationally connected to tub 64 by a hose (not shown). Any suitable pressure sensor 110, such as an electronic sensor, a manometer, or another suitable gauge or sensor, may be used. The pressure sensor 110 may generally measure the pressure of water in the tub 64. This pressure can then be used to estimate the height or amount of water in the tub 64. Pump 90 may be configured to operate in response to pressure sensor 101 measuring a water level exceeding a limit value, e.g., a maximum fill value. In other words, controller 100 may be configured to operate pump 90 to remove fluid from tub 64. Additionally, a suitable speed sensor can be connected to the motor 94, such as to the output shaft 98 thereof, to measure speed and indicate operation of the motor 94. Other suitable sensors, such as temperature sensors, water sensors, moisture sensors, etc., may additionally be provided in the washing machine appliance 50.
Operation of washing machine appliance 50 is controlled by a processing device or controller 100, that is operatively coupled to the input selectors 60 located on washing machine backsplash 56 for user manipulation to select washing machine cycles and features. Controller 100 may further be operatively coupled to various other components of appliance 50, such as the flow regulator (including valves 74, 75), motor 94, pressure sensor 110, other suitable sensors, etc. In response to user manipulation of the input selectors 60, controller 100 may operate the various components of washing machine appliance 50 to execute selected machine cycles and features.
While described in the context of specific example embodiments of washing machine appliance 50, using the teachings disclosed herein it will be understood that washing machine appliance 50 is provided by way of example only. Other washing machine appliances having different configurations, different appearances, or different features may also be used with the present subject matter as well.
In addition to pressure sensor 110, washing machine appliance 50 may include various other sensors, e.g., a turbidity sensor 132, a conductivity sensor 134, and a temperature sensor 136. Each of turbidity sensor 132, conductivity sensor 134, and temperature sensor 136 may be configured for signal communication with controller 100, e.g., sending measurement data or signals to controller 100. In some example embodiments, turbidity sensor 132, conductivity sensor 134, and temperature sensor 136 may be combined in any combination to reduce to the total number of sensors in washing machine appliance 50. Further, turbidity sensor 132, conductivity sensor 134, and temperature sensor 136 may be positioned in tub 64, e.g., on a bottom wall 66 of tub 64.
Controller 100 of washing machine appliance 50 may be configured to monitor, e.g., continuously, a pressure measurement of pressure sensor 110. The pressure measurement may be indicative of the height of the fluid in tub 64. Pressure sensor 110 may read values continuously, e.g., the values incrementally increase as the height of the fluid within tub 64 increases. Before filling tub 64 with fluid, controller 100 may record an ambient temperature measurement in response to the pressure measurement stabilizing, e.g., before washing machine appliance 50 begins operating, the ambient temperature measurement may be recorded. During a drain cycle of washing machine appliance 50, controller 100 may be configured to record a turbidity measurement from turbidity sensor 132, a conductivity measurement from conductivity sensor 134, and a temperature measurement from temperature sensor 136. These turbidity, conductivity, and temperature measurements may be recorded in response to the pressure measurement further incrementing, e.g., the pressure measurement may be incrementally increasing when the pressure measurement is not expected to incrementally increase.
When the various measurements are recorded, controller 100 may be configured to compare the turbidity measurement to a reference turbidity value, the conductivity measurement to a reference conductivity value, and the temperature measurement to the ambient temperature measurement. As seen in table 300 of
With table 300 of
Shown in
When the various measurements are recorded, controller 100 may, at 440, compare the turbidity measurement to a reference turbidity value, the conductivity measurement to a reference conductivity value, and the temperature measurement to the ambient temperature measurement. Thus at 460, controller 100 may determine the presence of fluid in tub 64 via the values of the turbidity measurement, the conductivity measurement, and the temperature measurement. As stated above, table 300 of
Referring again to
Length of Timer=BC+(TC*T)+(FC*FHt)
The algorithm described above is provided by way of example only and may include more or less variables in other example embodiments. In addition to the timer, pump 90 may also be deactivated in response to the determination that there is no fluid in tub 64 for a set length of time via turbidity sensor 132, conductivity sensor 134, and temperature sensor 136. The set length of time of determining no fluid in tub 64 may be at least five seconds.
Shown in
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
