Patent Application
20180347092
Laundry treating appliances, such as clothes washers, refreshers, and non-aqueous systems, can have a configuration based on a cabinet within which is housed the components of the appliance, including a liquid container, typically in the form of a tub. The tub typically houses a laundry container defining a treating chamber in which laundry items are placed for treating. The tub is dimensioned to accommodate tub movement within the cabinet, movement of the laundry container within the tub, and to support forces generated by the weight and rotation of the laundry container.
A suspension system typically connects the tub to the cabinet to support the movement of the tub and the laundry container within the cabinet, dampening any movement or vibrational transmission from the tub or the laundry container therein. Supporting the movement of the tub within the cabinet limits the capacity of the tub, thus limiting the capacity of the laundry container within the tub and the volume of the treating chamber directly limiting the volume of laundry that can be treated within the treating chamber.
An aspect of the present disclosure relates to a method of reducing displacement of a rotatable drum of a washing machine that includes a motor for rotating the rotatable drum, the method includes supporting the drum by a suspension system within a chassis and tuning the suspension system, the suspension system having six natural frequencies including three translational frequencies and three rotational frequencies, the suspension system includes at least one spring that is configured to group the three translational frequencies and three rotational frequencies into a first group determined by a predetermined first rotational speed range of the drum or the motor and a second group determined by a predetermined second rotational speed range of the drum or the motor that is separated from the predetermined first rotational speed range by at least 70 rpm, in this manner the first group and the second group are correlated to known speeds that can be accelerated through during a cycle of operation.
Another aspect of the present disclosure relates to a method of operating a laundry treating appliance having a rotatable drum driven by a motor, the method includes supporting the rotatable drum by a suspension system within a chassis, tuning the suspension system, the suspension system having six natural frequencies including three translational frequencies and three rotational frequencies, the suspension system includes at least one spring that is configured to group the three translational frequencies and three rotational frequencies into a first group determined by a predetermined first rotational speed range of the drum or the motor and a second group determined by a predetermined second rotational speed range of the drum or the motor that is separated from the predetermined first rotational speed range by at least 70 rpm, in this manner the first group and the second group are correlated to known speeds that can be accelerated through during a cycle of operation, accelerating the rotational speed of the rotatable drum to a speed faster than a first group of the two groups, and accelerating the rotational speed of the drum faster than a second group of the two groups.
Yet another aspect of the present disclosure relates to a method of reducing displacement of a rotatable drum of a washing machine that includes a motor for rotating the rotatable drum, the method includes supporting the drum by a suspension system within a chassis the suspension system having six natural frequencies including three translational frequencies and three rotational frequencies, the suspension system includes at least one spring that is configured to group the three translational frequencies and three rotational frequencies into a first group determined by a predetermined first rotational speed range of the drum or the motor and a second group determined by a predetermined second rotational speed range of the drum or the motor that is separated from the predetermined first rotational speed range, in this manner the first group and the second group are correlated to known speeds that can be accelerated through during a cycle of operation, and accelerating the drum, via the motor, to a rotational speed between the first group and the second group.
In the drawings:
The laundry treating appliance of
The laundry holding system includes a tub 14 and a drum 16 provided within the tub 14. The drum 16 is rotatable about an axis of rotation 17 and defines at least a portion of a treating chamber 18. The drum 16 can include a plurality of perforations 20 such that liquid can flow between the tub 14 and the drum 16 through the perforations 20. A plurality of baffles 22 can 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 the present disclosure for the laundry holding system to include only a tub with the tub defining the laundry treating chamber.
The laundry holding system can further include a door 24, which can be movably mounted to the chassis 12 to selectively close both the tub 14 and the drum 16. A bellows 26 can couple an open face of the tub 14 with the chassis 12, with the door 24 sealing against the bellows 26 when the door 24 closes the tub 14.
The washing machine 10 includes a suspension system 28 for dynamically suspending the laundry holding system within the structural support system. More specifically the tub 14 is supported within the chassis 12 by suspension system 28. The suspension system 28 can include multiple springs 30 suspending the tub 14 from the upper area of the chassis 12, while multiple struts 32 can be used to support the system from below. Preferably, three or more springs 30 are utilized to suspend the laundry holding system.
The washing machine 10 can 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 can include a source of water, such as a household water supply 40, which can include separate valves 42 and 44 for controlling the flow of hot and cold water, respectively. Water can 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 can be a diverter valve having two outlets such that the diverter mechanisms 48, 50 can selectively direct a flow of liquid to one or both of two flow paths. Water from the household water supply 40 can flow through the inlet conduit 46 to the first diverter mechanism 48 which can direct the flow of liquid to a supply conduit 52. The second diverter mechanism 50 on the supply conduit 52 can direct the flow of liquid to a tub outlet conduit 54 which can 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 can be supplied directly to the tub 14.
The washing machine 10 can 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 can include a dispenser 62 which can 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, now U.S. Pat. No. 8,196,441, issued Jun. 12, 2012, 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, now U.S. Pat. No. 8,388,695, issued Mar. 5, 2013, 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, now U.S. Pat. No. 8,397,328, issued Mar. 19, 2013, 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, now U.S. Pat. No. 8,813,526, issued Aug. 26, 2014, 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, now abandoned, 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, now U.S. Pat. No. 8,397,544, issued Mar. 19, 2013, 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, now U.S. Pat. No. 8,438,881, issued May 4, 2013, 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 can 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 can 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 can be configured to dispense a flow or stream of treating chemistry into the tub 14 by gravity, i.e. a non-pressurized stream. Water can 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 can 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 can 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 can flow by gravity to a sump 70 formed in part by a lower portion of the tub 14. The sump 70 can also be formed by a sump conduit 72 that can fluidly couple the lower portion of the tub 14 to a pump 74. The pump 74 can direct liquid to a drain conduit 76, which can drain the liquid from the washing machine 10, or to a recirculation conduit 78, which can terminate at a recirculation inlet 80. The recirculation inlet 80 can direct the liquid from the recirculation conduit 78 into the drum 16. The recirculation inlet 80 can 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 can be recirculated into the treating chamber 18 for treating the laundry within.
The liquid supply and/or recirculation and drain system can be provided with a heating system which can 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 can 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 can be supplied to the tub 14 through a steam outlet conduit 87. The steam generator 82 can 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 can 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 can 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 can 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 can include a motor 88, which can be directly coupled with the drum 16 through a drive shaft 90 to rotate the drum 16 about a rotational axis during a cycle of operation. The motor 88 can be a brushless permanent magnet (BPM) motor having a stator 92 and a rotor 94. Alternately, the motor 88 can 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, can also be used. The motor 88 can 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 can include a controller 96 located within the chassis 12 and a user interface 98 that is operably coupled with the controller 96. The user interface 98 can 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 can enter different types of information including, without limitation, cycle selection and cycle parameters, such as cycle options.
The controller 96 can 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 can include the machine controller and a motor controller. Many known types of controllers can be used for the controller 96. 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 effect 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), can be used to control the various components.
As illustrated in
The controller 96 can 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 can 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 can also be coupled with one or more sensors 106 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 106 that can 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 and a motor torque sensor, which can be used to determine a variety of system and laundry characteristics, such as laundry load inertia or mass.
In one example, one or more load amount sensors 106 can also be included in the washing machine 10 and can 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 can 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 can 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.
The one or more load amount sensors 106 can be any suitable type of sensor capable of measuring the weight or volume of laundry in the treating chamber 18. Non-limiting examples of load amount sensors 106 for measuring the weight of the laundry can include load volume, pressure, or force transducers which can include, for example, load cells and strain gauges. It has been contemplated that the one or more such sensors 106 can be operably coupled to the suspension system 28 to sense 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 can 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 can be used to determine the volume of laundry located in the treating chamber 18.
Alternatively, it has been contemplated that the washing machine 10 can have one or more pairs of feet 108 (
Referring now to
Further, the springs 30 can have particular spring stiffness. The stiffness of the spring 30 is the rigidity of the spring 30 or the resistance to deformation the spring 30 has. The stiffness, or spring constant, (k) is the ratio of force (F) to displacement (δ) produced by the force, such that the stiffness can be defined as
k=F/δ. (1)
The spring(s) 30 can also define six suspension natural frequencies for movement of the tub 14 about the suspension system 28. The term “natural frequency” as used herein is the frequency at which a system, such as the suspension system 28, tends to oscillate in the absence of any driving or damping force(s) and at which the system can resonate if held at that frequency. The six natural frequencies can include, but are not limited to, three rotational frequencies and three translational frequencies. The three rotational frequencies and three translational frequencies relate to rotational and linear oscillating movement, respectively, of the drum 16 in three-dimensional space during operation of the washing machine 10. A horizontal axis passing side-to-side through the washing machine 10 can be defined as an X-axis, a horizontal axis that is perpendicular to the X-axis and passes front-to-back through the washing machine 10 can be defined as a Z-axis, and a vertical axis of the washing machine 10 can be the Y-axis. The Z-axis lies generally parallel to the rotational axis of the drum 16. The rotational frequencies can be rotational movement about any of these axes. For the horizontal axis washing machine, three translational degrees of freedom can lie in the X-axis, Y-axis and the Z-axis translational movements. The translational movements can be linear displacement of the drum 16 along the axes as opposed to the rotational movements about the rotational degrees of freedom.
During operation of the washing machine 10, the six natural frequencies will be passed through during acceleration of the drum 16 through various rotational speeds of the drum 16 defined as rotations per minute (rpm). The rotations per minute can be representative of a motor speed driving the drum 16 at a particular number of rotations per minute. During the acceleration, a moment occurs where the drum 16 reaches a rotational speed that coincides with a particular natural frequency of the suspension system 28. The drum 16 will resonate with the suspension system 28 at a particular rotational speed of the drum 16, causing increasing rotational or translational vibrations, and displacement of the drum 16. At such a moment, the vibration of the suspension system 28 causes oscillations and resonance, which causes tub 14 displacement, which can lead to contact between the tub 14 and the drum 16, or the tub 14 and the chassis 12, as well as washing machine ‘walking.’ Washing machine ‘walking,’ as understood in the art, occurs when the resonance of the tub 14 causes the washing machine 10 to move from its initial position on the surface 109 upon which it rests.
In order to avoid excessive tub 14 displacement, it is preferable to tune the suspension system 28 to group the natural frequencies into ranges. More specifically, the springs 30 can be “tuned” such that the natural frequencies are changed. The natural frequencies can be tuned to correspond to a different rotational speed of the drum 16 or motor 88 and in this manner, the grouping of the frequencies can be facilitated. Tuning can be accomplished by changing the spring angle 118 or the stiffness of the springs 30. Additionally, tuning can be accomplished by changing the location or orientation of the springs 30, utilizing more or less springs, or using a counterweight mass and positioning such a counterweight. Upon grouping the natural frequencies, the drum 16 can be accelerated through the rotational speeds in which the frequencies are grouped, avoiding the issues associated with operation at those rotational speeds, such as the tub-chassis contact, etc. Put another way, the suspension system 28 can be tuned such that the natural frequencies are grouped within set rotational speeds and the drum 16 can be quickly accelerated through such rotational speeds so adverse movement is avoided.
Varying the spring angle or stiffness can vary the rotational speed at which the natural frequency occurs. For example, by varying the angle for the springs 30 in the suspension system 28, the natural frequency can be varied as shown in
While changing the spring angle 118 can be used to vary the natural frequency, some natural frequencies are substantially unchanged by varying the spring angle 118. In order to change the natural frequency without modifying the spring angles 118, the spring stiffnesses can be varied. Looking at the ‘RotationX’ rotational frequency 142a in particular, increasing the spring stiffness by a value of between 0.5-1.0 Newtons per millimeter (k) can change the rotational speed by about 6-12 rpm at which the natural frequency occurs. Therefore, utilizing the spring angle 118 and the spring stiffness, the natural frequencies can be tuned such that groups can be defined based upon the rotational speed of the drum 16 or motor 88.
Looking now at the plot illustrated in
It is contemplated that the six natural frequencies can be grouped in any manner, having any number of frequencies in any group, each group having at least one frequency. For example, the spring angle 118 and the stiffness can be varied to minimize the rotational range that the two group covers. By way of non-limiting example, utilizing a spring angle of 15.2-degrees and a spring stiffness of 60 would group the second group 152 into a range between about 170-220 rpm. At those values, the first group has a rotational speed range of about 70-95 rpm. At least a value of 70 rpm can separate the first group 150 and the second group 152 and in that specific example a separation of 80 rpm can be realized.
Turning now to
During operation, the rotation of the drum 16 can be accelerated to an intermediate speed above the first group 150, such as to about 130 rpm in one example, having a spring angle of 8.5 degrees and a stiffness of 5.7 Newtons per millimeter. The rotational speed of the drum 16 can remain at about 130 rpm providing the opportunity to satellize the clothing, mix treating chemistry into the clothing, provide for initial low speed water extraction, or determine parameters of the system such as motor torque, drum imbalance, load imbalance, imbalance magnitude, drum position, load position, inertia, or friction in non-limiting examples. After performing the desired function at the intermediate rotational speed, the drum 16 can be accelerated to a rotational speed greater than the second group 152. The accelerations through the first group 150 and the second group can be done quickly so as to avoid operating in the adverse speed ranges. For example, the rotational speed of the drum 16 can be increased quickly to about 130 rpm, avoiding any prolonged operation at the rotational speed of the first group 150. There, the laundry within the treating chamber 18 can be satellized and parameters of the washing machine 10 can be determined. After determining the parameters, the drum 16 can be accelerated by the motor 88 through the second group 152 to about 300 rpm, again avoiding any prolonged operation within that speed range. In this manner, the natural frequencies of both groups 150, 152 can be avoided during operation. Therefore, a complete cycle of operation can be completed at multiple rotational speeds while generally avoiding operation within the natural frequency groups 150, 152, minimizing the potential for drum 16 oscillation or resonance at those frequencies to generate wash unit displacement.
It should be understood that for
Turning now to
At 206, the suspension system 28 can be tuned to group the natural frequencies into ranges related to the rotational speed of the drum. As described above, tuning can be accomplished by varying the spring angle 118 or by changing the spring stiffness of the springs 30, using more or less springs 30, or changing the location or orientation of the springs 30, or use of a counterweight mass and positioning of such a counterweight. It is contemplated that the grouped natural frequencies will be separated by at least 70 rpm. The 70 rpm range provides for a broad enough range to avoid the natural frequencies of the suspension system 28 and enable washing machine operation between the groups of natural frequencies. It further provides cushion for accelerating and decelerating the rotation of the drum 16 without spending too much time within the frequency ranges for the groups of natural frequencies.
The present disclosure achieves a variety of benefits including that displacement of the drum 16, tub 14, or entire washing machine 10, caused by rotation of the drum at a natural frequency of the washing machine suspension system 28, can be minimized. Reducing or eliminating the potential for displacement also allows the tub to be placed closer to the chassis, which can in turn lead to the ability to increase the tub and the treating capacity for the washing machine. The present disclosure also allows the natural frequencies of the suspension system to be grouped without rotating the drum at one of the suspension system natural frequencies.
To the extent not already described, the different features and structures of the various embodiments can 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 can be mixed and matched as desired to form new embodiments, whether or not the new embodiments are expressly described. All combinations or permutations of features described herein are covered by this disclosure.
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. Reasonable variation and modification are possible within the scope of the forgoing disclosure and drawings without departing from the spirit of the invention which is defined in the appended claims.
This application is a divisional of U.S. patent application Ser. No. 15/047,075, filed Feb. 18, 2016, which is hereby incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15047075 | Feb 2016 | US |
| Child | 16055781 | US |
