Patent application title: MOTOR-MOUNTED BALANCE RING FOR A WASHING MACHINE APPLIANCE
Richard Allen Vincent (Louisville, KY, US)
Christopher Nils Naber (Louisville, KY, US)
GENERAL ELECTRIC COMPANY
IPC8 Class: AD06F2300FI
Class name: Machines tumbling cage type tumbler supports, bearings or drive
Publication date: 2012-11-01
Patent application number: 20120272690
A balance ring for a washing machine appliance that is mounted onto the
motor of the washing machine is provided. Because the balance ring is
placed onto the motor of the washing machine rather than the wash
chamber, additional space is made available for the wash chamber that can
improve the load capacity of the washing machine. The balance ring can
provide improved balance performance because of its additional moment
length from the center of gravity relative to conventional balance rings.
1. A washing machine, comprising: a wash tub; a wash basket rotatably
mounted in said wash tub, said wash basket having a wash basket opening
for receiving wash fluid and a wash load therein; a motor in mechanical
communication with said wash basket and configured for causing said wash
basket to rotate, said motor having an axis of rotation, said motor
further comprising an external surface that is offset from the axis of
rotation, the external surface rotating about the axis of rotation when
said motor is activated; and, a balance ring mounted onto the external
surface of the motor, the balance ring configured to offset imbalances
created by articles in the wash tub when said wash basket is rotated by
2. A washing machine as in claim 1, wherein said balance ring comprises a toroidal shape that defines at least one cavity.
3. A washing machine as in claim 2, wherein the cavity of said balance ring comprises a liquid.
4. A washing machine as in claim 2, wherein the cavity of said balance ring comprises a plurality of metal balls.
5. A washing machine as in claim 2, wherein said motor comprises a pancake motor.
6. A washing machine as in claim 2, wherein the external surface of said motor is parallel to the axis of rotation of said motor.
7. A washing machine as in claim 2, wherein the washing machine is a vertical axis washing machine.
8. A washing machine as in claim 2, wherein the washing machine is a horizontal axis washing machine.
9. A washing machine, comprising: a wash tub; a wash basket rotatably mounted in said wash tub, said wash basket configured for receiving wash fluid and a wash load therein; a motor having an axis of rotation, said motor having a rotor that is configured for rotating said wash basket about the axis of rotation; and, a toroidal ring mounted onto the rotor of said motor at a position offset from the axis of rotation of said motor, said ring defining a cavity into which a mass has been placed, the mass configured to move within the ring to offset imbalances caused by articles in said wash basket when rotated by said motor.
10. A washing machine as in claim 9, wherein said rotor defines an outermost, circumferential surface; and wherein said ring is mounted upon the outermost, circumferential surface of said rotor.
11. A washing machine as in claim 10, wherein the outermost, circumferential surface of said rotor is parallel to the axis of rotation of said motor.
12. A washing machine as in claim 9, wherein the mass in said toroidal ring comprises a liquid.
13. A washing machine as in claim 9, wherein the mass in said toroidal ring comprises a metal.
14. A washing machine as in claim 9, wherein said motor comprises a pancake motor.
15. A washing machine as in claim 9, wherein the washing machine is a vertical axis washing machine.
16. A washing machine as in claim 9, wherein the washing machine is a horizontal axis washing machine.
17. A washing machine as in claim 9, wherein said toroidal ring is press fit onto said rotor.
FIELD OF THE INVENTION
 The present invention relates to a balance ring for a washing machine appliance that is mounted onto the motor of the washing machine.
BACKGROUND OF THE INVENTION
 During the operation of a washing machine, particularly during spin cycles, the machine can sometimes experience an extreme vibration. These vibrations can even cause displacement of the washing machine as it "walks" across a surface such as a floor. Typically, this event is due to the different shapes and densities of the clothing or objects that are being washed which, after the washing cycle and draining the washing basket, can stick together and cause differences in the center of mass inside the wash basket. The vibration problem can be caused by the introduction of relatively heavier objects into the washing basket such as e.g., shoes.
 By way of example, after the washing cycle and draining of the washing liquid from the basket, the shoes may be located on one side of the washing basket or in a manner that causes the center of mass of the combined washing basket and articles (such as the shoes, clothes, and other items being washed) to be off center. As the washing basket is rotated, particularly at high speeds, the off centering and centrifugal forces creates an imbalance that can generate undesired strain in the washing machine components, an undesirable level of noise, and/or "walking" of the appliance. In an extreme or prolonged situation, the imbalance created by the excessive vibration can also wear-out and damage the washing machine components.
 As a result, in order to prevent this imbalance, various devices have been proposed. For example, washing machines have been equipped with balance rings, which are typically hollow rings placed on the top part of the washing basket. Inside the ring (or toroid) a weight such a liquid or solid balls have been inserted. During operation, the ring will act as a counterweight to the load of clothes because liquid or solid balls that move to position within the ring that counters the centrifugal forces created by the articles in the wash so as to balance the basket. Balance rings of various configurations including chambers, partitions, and other elements to improve the balancing effect have also been proposed.
 The above mentioned balance rings are typically attached or connected in some manner with the washing chamber. For example, for a vertical axis washing machine, the balance ring can be attached to the bottom of the washing chamber while for a horizontal axis washing machine, it can be attached to the front, back, or both ends of the washing chamber. Unfortunately, these arrangements subtract from the total capacity that can be provided for the washing chamber resulting in smaller loads of articles that can be washed. As load capacity can be an important factor in a consumer's purchasing decision, reductions in that capacity are usually undesirable.
 Accordingly, a device for balancing the load of a washing machine would be beneficial. A device that can help balance the load of a washing machine without reducing the load capacity of the washing machine would be particularly useful. Such a device that can be adapted within the conventional used cabinet sizes for a washing machine would also be particularly useful.
BRIEF DESCRIPTION OF THE INVENTION
 Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
 In one exemplary embodiment, the present invention provides a washing machine that includes a wash tub and a wash basket. The wash basket is rotatably mounted in the wash tub. The wash basket has a wash basket opening for receiving wash fluid and a wash load therein. A motor is in mechanical communication with the wash basket and is configured for causing the wash basket to rotate. The motor has an axis of rotation and includes an external surface that is offset from the axis of rotation. The external surface rotates about the axis of rotation when the motor is activated. A balance ring is mounted onto the external surface of the motor. The balance ring is configured to offset imbalances created by articles in the wash tub when the wash basket is rotated by the motor.
 In another exemplary embodiment, the present invention provides a washing machine that includes a wash tub and a wash basket rotatably mounted in the wash tub. The wash basket has an opening configured for receiving wash fluid and a wash load therein. A motor is provided that has an axis of rotation and a rotor that is configured for rotating the wash basket about the axis of rotation. A toroidal ring is mounted onto the rotor of the motor at a position offset from the axis of rotation of the motor. The ring defines a cavity into which a mass has been placed. The mass is configured to move within the ring to offset imbalances caused by articles in the wash basket when rotated by the motor.
 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.
BRIEF DESCRIPTION OF THE DRAWINGS
 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, in which:
 FIG. 1 provides a perspective view of an exemplary embodiment of a washing machine of the present invention. A portion of the cabinet has been removed to reveal certain elements of the interior.
 FIG. 2 is a partial schematic view of the interior of the exemplary embodiment of FIG. 1.
 FIG. 3 is a perspective view of an exemplary embodiment of a motor as may be used with the present invention.
 FIG. 4 is a cross-sectional view of the exemplary embodiment of FIG. 3.
DETAILED DESCRIPTION OF THE INVENTION
 The present invention relates to a balance ring for a washing machine appliance that is mounted onto the motor of the washing machine. Because the balance ring is placed onto the motor of the washing machine rather than the wash chamber, additional space is made available for the wash chamber that can improve the load capacity of the washing machine. The balance ring can provide improved balance performance because of its additional moment length from the center of gravity relative to conventional balance rings.
 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 or spirit 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.
 FIG. 1 is a perspective view partially broken away of an exemplary vertical axis washing machine 50 including a cabinet 52 and a cover 54. A backsplash 56 extends from cover 54, and a control panel 58 including a plurality of input selectors 60 is coupled to backsplash 56. Control panel 58 and input selectors 60 collectively form a user interface input for operator selection of machine cycles and features, and in one embodiment, a display 61 indicates selected features, a countdown timer, and/or other items of interest to machine users. A lid 62 is mounted to cover 54 and is rotatable about a hinge (not shown) between an open position (not shown) facilitating access to wash tub 64 located within cabinet 52, and a closed position (shown in FIG. 1) forming an enclosure over wash tub 64.
 Wash tub 64 includes a bottom wall 66 and a sidewall 68, and a basket 70 that is rotatably mounted within wash tub 64. A pump assembly 72 is located beneath tub 64 and basket 70 for gravity assisted flow when draining tub 64. Pump assembly 72 includes a pump 74 and a motor 76. A pump inlet hose 80 extends from a wash tub outlet 82 in tub bottom wall 66 to a pump inlet 84, and a pump outlet hose 86 extends from a pump outlet 88 to a water outlet 90 and ultimately to a building plumbing system discharge line (not shown) in fluid communication with outlet 90.
 FIG. 2 is a front elevational and schematic view of washing machine 50 including wash basket 70 movably disposed and rotatably mounted in wash tub 64 in a spaced apart relationship from tub sidewall 68 and the tub bottom 66. Basket 70 includes an opening for receiving wash fluid and a washload therein. Basket 70 includes a plurality of perforations 71 therein to facilitate fluid communication between an interior of basket 70 and wash tub 64.
 An agitation element 92, such as a vane agitator, impeller, auger, or oscillatory basket mechanism, or some combination thereof is disposed in basket 70 to impart an oscillatory motion to articles and liquid in basket 70. In different embodiments, agitation element 92 includes a single action element (i.e., oscillatory only), double action (oscillatory movement at one end, single direction rotation at the other end) or triple action (oscillatory movement plus single direction rotation at one end, singe direction rotation at the other end). As illustrated in FIG. 2, agitation element 92 is oriented to rotate about a vertical axis A. Basket 70 and agitator 92 are driven by pancake motor 94. As motor output shaft 98 is rotated, basket 70 and agitation element 92 are operated for rotatable movement within wash tub 64.
 Washing machine 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. Pump assembly 72 is selectively activated, in the example embodiment, to remove liquid from basket 70 and tub 64 through drain outlet 90 during appropriate points in washing cycles as machine 50 is used.
 Operation of machine 50 is controlled by a controller or processing device (not shown), that is operatively coupled to the user interface input located on washing machine backsplash 56 (shown in FIG. 1) for user manipulation to select washing machine cycles and features. In response to user manipulation of the user interface input, the controller operates the various components of machine 50 to execute selected machine cycles and features.
 In an illustrative embodiment, laundry items are loaded into basket 70, and washing operation is initiated through operator manipulation of control input selectors 60 (shown in FIG. 1). Wash tub 64 is filled with water and mixed with detergent to form a wash fluid, and contents of the basket 70 are agitated with agitation element 92 for cleansing of laundry items in basket 70. More specifically, agitation element 92 is moved back and forth in an oscillatory back and forth motion. In the illustrated embodiment, agitation element 92 is rotated clockwise a specified amount about the vertical axis of the machine, and then rotated counterclockwise by a specified amount. The clockwise/counterclockwise reciprocating motion is sometimes referred to as a stroke, and the agitation phase of the wash cycle constitutes a number of strokes in sequence. Acceleration and deceleration of agitation element 92 during the strokes imparts mechanical energy to articles in basket 70 for cleansing action. The strokes may be obtained in different embodiments with a reversing motor, a reversible clutch, or other known reciprocating mechanism.
 After the agitation phase of the wash cycle is completed, tub 64 is drained with pump assembly 72. Laundry items are then rinsed and portions of the cycle repeated, including the agitation phase, depending on the particulars of the wash cycle selected by a user. One or more spin cycles may also be used. In particular, a spin cycle may be applied after the wash cycle and/or after the rinse cycle in order to wring wash fluid from the articles being washed. During a spin cycle, basket 70 is rotated at relatively high speeds. As previously described, the articles inside basket 70 can sometimes cause an imbalance leading to undesirable vibrations of machine 50 during operation.
 Accordingly, washing machine 50 is equipped with a balance ring 106 that operates to counteract imbalances in the wash load placed into wash tub 64. However, unlike conventional placements, balance ring 106 is placed onto motor 94 instead of wash basket 70. As such, balance ring 106 does not subtract from the space available for wash basket 70, which allows the size of basket 70 to be maximized for increased wash load capacity.
 More particularly, as shown in the perspective view of FIG. 3, motor 94 includes a rotor 104 that is driven or rotated when motor 94 is activated. Rotor 104 includes a plurality of vents 102 that allow for the flow of air to help cool motor 94 during operation. Magnets 95 (FIG. 4) placed inside rotor 104 are used with forces created by electrical currents to cause rotor 104 to rotate about axis A in a manner well known in the art. An opening 100 in the center of rotor 104 is provided for the receipt of shaft 98, which is used to place motor 104 in mechanical communication with wash basket 70. Accordingly, the rotations of rotor 104 about axis of rotation A can be used to rotate wash basket 70 and agitation element 92.
 Rotor 104 defines an external surface 109. For this exemplary embodiment, external surface 109 is the outermost, circumferential surface of rotor 104. Additionally, for this exemplary embodiment, surface 109 is parallel to the axis of rotation A of motor 94 and is offset from axis A. The offset provides length for a moment created by balance ring 106 in order to counter weight imbalances in basket 70 during e.g., spin cycles or other operations that create centrifugal forces in basket 70.
 Balance ring 106 is mounted upon external surface 109. Preferably, balance ring 106 is positioned using a press fit assembly. For example, balance ring 106 may be constructed as a plastic that is snapped or pressed onto external surface 109 with a tolerance fit. Pegs, detents, or other features may also be used to secure the position of balance ring 106. Balance ring 106 may also be adhered or fastened to surface 109. However, other constructions may be used as well. As shown most clearly in FIG. 2, because balance ring 106 is positioned on the outermost, circumferential surface 109 of motor 94, additional space is provided for the increased capacity of wash basket 70.
 Referring now to FIGS. 3 and 4, balance ring 106 has a toroidal shape that defines a cavity 108 into which a movable mass 110 has been placed. For the exemplary embodiment shown, mass 110 is a liquid such as e.g., salt water. However, other materials may be used for mass 110 including movable solids such as metal balls. Combinations of liquids and movable solids may be used as well. In addition, ring 106 may be provided with a number of partitions (not shown) within cavity 108 to slow the movement of liquid about ring 106. As will be understood by one of ordinary skill in the art using the teachings disclosed herein, a variety of constructions may be used for balance ring 106 that allow it to offset imbalances created by articles in wash basket 70 as it is rotated by motor 94.
 Although the above exemplary embodiment was described using a vertical axis washing machine 50, the present invention may also be used with a horizontal axis washing machine as well. Additionally, the present invention is not limited to the particular shapes for motor 94 and balance ring 106 as shown--it being understood that other shapes and configurations may be applied with the teachings set forth in the present disclosure.
 Accordingly, the present invention provides for improvement in the wash load capacity of a washing machine by placing the balance ring on a motor powering a wash basket rather than on the wash basket itself. In addition, relative to conventionally-placed balance rings, improved balance performance is expected due to the additional moment length from the center of gravity that is created by positioning balance ring about the motor.
 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.
Patent applications by GENERAL ELECTRIC COMPANY
Patent applications in class Cage type tumbler supports, bearings or drive
Patent applications in all subclasses Cage type tumbler supports, bearings or drive