This invention relates generally to washing machines and, more particularly, to a drive assembly for washing machines.
Washing machines typically include a cabinet that houses a stationary tub for containing wash and rinse water. A wash basket is rotatably mounted within the stationary tub, and an agitating element is positioned within the wash basket. A drive assembly located below the stationary tub is configured to rotate and control movement of the agitating element and/or the wash basket to clean the articles loaded into the wash basket. At an end of a wash cycle, a pump assembly is used to drain the soiled water to a drainage system.
Conventional drive assemblies generally include a motor, an input shaft coupled to the motor and an output shaft operatively coupled to the input shaft. In at least one conventional drive assembly, the input shaft is coupled at a first end to a pulley that is operatively coupled to the motor by a belt. The input shaft is operatively coupled at a second end opposing the first end to the output shaft. The output shaft is operatively coupled to the agitating element to produce an agitating movement and/or a continuous direct spin. The drive assembly also includes a gear assembly that drives the input shaft and output shaft to rotate about a vertical axis. However, in conventional drive assemblies relative movement of the input shaft with respect to the output shaft is restricted for facilitating a stable operation and performance of the drive assembly. The useful life of the gear assembly is greatly reduced due to undesirable contact between the components of the drive assembly and/or the misalignment of the input shaft and the output shaft. Further, such misalignment may produce undesirable noise during operation of the washing machine.
In one aspect, a drive assembly for a washing machine is provided. The drive assembly includes a motor. An input shaft is operatively coupled to the motor and an output shaft is operatively coupled between the input shaft and an agitator. A housing is positioned about at least a portion of the input shaft and at least a portion of the output shaft. A gear assembly is positioned within the housing and drivingly couples the input shaft to the output shaft. A first bearing is positioned about a bottom end of the input shaft opposing the top end. The first bearing is configured to radially support the input shaft and define a first radial clearance between the top end of the input shaft and the housing for facilitating radial movement of the top end of the input shaft with respect to the output shaft.
In another aspect, a washing machine is provided. The washing machine includes a cabinet and a basket positioned within the cabinet. A motor is operatively coupled to the basket and configured to rotate the basket. A transmission assembly including an input shaft and an output shaft is provided. The input shaft is operatively coupled to the motor and the output shaft. A housing defines a chamber for containing the transmission assembly. A first sleeve bearing is positioned about a first end of the input shaft. The first sleeve bearing is configured to radially support the input shaft and define a radial clearance between the input shaft and the housing at a second end of the input shaft opposing the first end for facilitating radial movement of the second end of the input shaft.
In another aspect, a method is provided for assembling a washing machine. The method includes providing a cabinet, positioning a basket within the cabinet, and coupling a motor to the basket. The motor is configured to rotate the basket. A transmission assembly is operatively coupled to the motor. The transmission assembly includes an input shaft at least partially positioned within a housing. A first sleeve bearing is positioned about a first end of the input shaft. The first sleeve bearing is configured to radially support the input shaft and define a radial clearance between the input shaft and the housing at a second end of the input shaft opposing the first end for facilitating radial movement of the second end of the input shaft. An output shaft is operatively coupled to the input shaft. The method further includes operatively coupling a gear assembly to the motor. The gear assembly includes a sun gear positioned about the second end of the input shaft, a plurality of planet gears positioned about the sun gear, and a stationary ring gear positioned about the plurality of planet gears and fixedly coupled to the housing.
Washing machine 100 includes a cabinet 102 and a cover 104. A backsplash 106 extends from cover 104, and a control panel 108 including a plurality of input selectors 110 is coupled to backsplash 106. Control panel 108 and input selectors 110 collectively form a user interface input for operator selection of machine cycles and/or washing features. In the exemplary embodiment, a display 112 indicates selected features, a countdown timer and/or other items of interest to machine users. A lid 114 is mounted to cover 104 and is rotatable about a hinge (not shown) between an open position (not shown) facilitating access to a wash tub 116 mounted within cabinet 102, and a closed position (shown in
Wash tub 116 includes a basket 118 rotatably mounted within wash tub 116. In one embodiment, basket 118 includes a plurality of perforations defined therein for facilitating fluid communication between an interior cavity defined by the basket 118 and wash tub 116. A drive assembly 120 is mounted within cabinet 102 and positioned with respect to basket 118. Drive assembly 120 includes a motor 122, an input shaft 124 and an output shaft 126. Input shaft 124 is coupled to a pulley 128, which is driven by a belt 130 coupling pulley 128 to motor 122. Therefore, when motor 122 starts running, input shaft 124 rotates about a vertical axis (not shown) through pulley 128 and belt 130. Input shaft 124 is also engaged with a brake assembly 132. Drive assembly 120 is operatively coupled to control panel 108 and executes selected wash and rinse cycles of washing machine 100.
Drive assembly 120 also includes a bearing, such as a first sleeve bearing 155, positioned about input shaft 124 and configured to radially support input shaft 124. In a particular embodiment, first sleeve bearing 155 also axially supports input shaft 124. As shown in
In one embodiment, drive assembly 120 also includes a bearing, such as a second sleeve bearing 157, positioned about output shaft 126 and configured to radially support output shaft 126. In a particular embodiment, second sleeve bearing 157 also axially supports output shaft 126. As shown in
In one embodiment, second sleeve bearing 157 limits the radial movement of the top end of output shaft 126 and facilitates the radial movement of the bottom end of output shaft 126. As such, the bottom end of output shaft 126 may move radially with respect to the top end of input shaft 124. In alternative embodiments, any suitable bearing system known to those skilled in the art and guided by the teachings herein provided may be used to support the top end of output shaft 126 while allowing the radial movement of the bottom end of output shaft 126 with respect to input shaft 124.
In one embodiment, a ball bearing 158 is movably positioned between the top end of input shaft 124 and the bottom end of output shaft 126 for facilitating relative movement between input shaft 124 and output shaft 126. Ball bearing 158 limits axial movement of input shaft 124 and/or output shaft 126 for facilitating transferring an axial thrust load of output shaft 126 to input shaft 124 thereby carrying the axial thrust load of output shaft 126. Ball bearing 158 facilitates radial movement of the bottom end of output shaft 126 with respect to the top end of input shaft 124. Further, in a particular embodiment, ball bearing 158 is movable for facilitating operating input shaft 124 and output shaft 126 at a best center relative to sun gear 150.
In operation, motor 122 is energized to drive input shaft 124 to rotate. Sun gear 150 mounted at the top end of input shaft 124 then drives planet gears 152 to rotate within ring gear 154. Planet gears 152 in turn drive planet carrier 156 to rotate together with output shaft 126. In one embodiment, input shaft 124 is radially supported at least partially by first sleeve bearing 155 and/or gear assembly 140. As such, the top end of input shaft 124 may be radially positioned in an operating center with respect to gear assembly 140. First sleeve bearing 155, second sleeve bearing 157 and radial clearances 160, 162 enable the top end of input shaft 124 and the bottom end of output shaft 126 to move radially with respect to each other.
In one embodiment, a method is provided for assembling a washing machine. The method includes providing a cabinet, positioning a basket within the cabinet, and drivingly coupling a motor to the basket. The motor is configured to rotate the basket. A transmission assembly is operatively coupled to the motor. The transmission assembly includes an input shaft at least partially positioned within a housing. A first sleeve bearing is positioned about a first end of the input shaft. The first sleeve bearing is configured to radially and/or axially support the input shaft and define a radial clearance between the input shaft and the housing at a second end of the input shaft opposing the first end for facilitating radial movement of the second end of the input shaft.
An output shaft is operatively coupled to the input shaft. In one embodiment, a second sleeve bearing is positioned about a first end of the output shaft. The second sleeve bearing is configured to radially and/or axially support the output shaft and define a second radial clearance between a second end of the output shaft opposing the first end and the housing for facilitating radial movement of the second end of the output shaft with respect to the second end of the input shaft.
A gear assembly is operatively coupled to the motor. The gear assembly includes a sun gear positioned about the second end of the input shaft. A plurality of planet gears is positioned about the sun gear. A stationary ring gear is positioned about the plurality of planet gears and fixedly coupled to the housing. In one embodiment, a ball bearing is movably positioned between the second end of the input shaft and the second end of the output shaft. The ball bearing is configured for axially supporting the input shaft and facilitating aligning the input shaft and the output shaft.
While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.
Number | Name | Date | Kind |
---|---|---|---|
3662622 | Neumann | May 1972 | A |
4255952 | Johnson | Mar 1981 | A |
4270411 | Pengo et al. | Jun 1981 | A |
4283928 | Stone | Aug 1981 | A |
4317343 | Gerry | Mar 1982 | A |
5209085 | Brien | May 1993 | A |
5267456 | Nukaga et al. | Dec 1993 | A |
5269160 | Wood | Dec 1993 | A |
5381677 | Park et al. | Jan 1995 | A |
5551261 | Lyu et al. | Sep 1996 | A |
5551262 | Seo | Sep 1996 | A |
5680778 | Seo | Oct 1997 | A |
5842358 | Koo et al. | Dec 1998 | A |
5860299 | Eum et al. | Jan 1999 | A |
5873269 | Hong et al. | Feb 1999 | A |
5884507 | Lee et al. | Mar 1999 | A |
5887458 | Bae | Mar 1999 | A |
5934107 | Lee et al. | Aug 1999 | A |
5950459 | Takagi et al. | Sep 1999 | A |
6077184 | Lee | Jun 2000 | A |
6176108 | Bae et al. | Jan 2001 | B1 |
6499323 | Skrippek et al. | Dec 2002 | B2 |
20040163429 | Lim | Aug 2004 | A1 |
20040168485 | Lim | Sep 2004 | A1 |
20050011233 | Vaidhyanathan et al. | Jan 2005 | A1 |
20050081573 | Han | Apr 2005 | A1 |
20050166643 | Cho et al. | Aug 2005 | A1 |
20050223754 | Choi | Oct 2005 | A1 |
20060010612 | Kim et al. | Jan 2006 | A1 |
Number | Date | Country | |
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20080060388 A1 | Mar 2008 | US |