The present disclosure relates primarily to horizontal axis washing machines, and electric motor and controller assemblies for horizontal axis washing machines.
Many horizontal axis washing machines—also referred to as “front loaders” because laundry is loaded through a door on the front side of the machine—are commonly provided with a variable speed electric motor for driving rotation of a laundry tub. The electric motor is typically located adjacent the tub and mechanically coupled to the tub using a belt system. A controller for the electric motor is mounted away from the electric motor, often adjacent to a controller for the washing machine, and electrically coupled to the electric motor via a cable assembly. While the motor shaft is generally horizontal, e.g., typically between 0° and 20°, those skilled in the art will readily recognize that the laundry tub axis of such front loaders can vary from approximately 0° to approximately 45° with respect to the horizontal.
As recognized by the present inventors, these known front loading washing machines have several disadvantages. For example, locating the motor controller away from the motor requires use of the cable assembly, which typically includes interference retarding components to reduce television interference. Additionally, because the motor controllers commonly include heat sinks mounted within a controller housing—also referred to as a drip shield—the controller housing is unnecessarily large, resulting in increased materials cost, and restricts heat dissipation from the heat sink.
To solve these and other needs, the present inventors have succeeded at designing, among other things, an integrated motor and controller assembly for horizontal axis washing machines, i.e., front loading washing machine.
According to various embodiments of the present disclosure, an electric motor and controller assembly for a horizontal axis washing machine includes an electric motor and a controller. The controller is mounted to an endshield of the electric motor. The controller includes a circuit board and an insulating shield positioned between the circuit board and the motor endshield.
According to various other embodiments of the present disclosure, an electric motor and controller assembly for a horizontal axis washing machine includes an electric motor and a controller. The controller includes software for controlling operation of the electric motor in the horizontal axis washing machine, and is mounted directly to an endshield of the electric motor. The endshield is mounted directly to a stator of the motor.
According to still other various embodiments of the present disclosure, an electric motor and controller assembly for a horizontal axis washing machine includes an electric motor and a controller. The controller is mounted to one of a pair of opposing motor endshields. Each endshield supports a bearing and each bearing supports an opposing end of a shaft of the motor.
According to yet other various embodiments of the present disclosure, a horizontal axis washing machine includes a tub, an electric motor, and a motor controller for the electric motor. The motor controller is mounted directly to one of a pair of opposing endshields that are mounted directly to a stator of the motor. Each endshield is structured to support a bearing. The bearings support opposing ends of a shaft of the motor and provide vibration damping during operation of the motor. The controller includes a circuit board and an insulating shield positioned between the circuit board and the motor endshield to which the controller is directly mounted.
Further embodiments of the present disclosure will be in part apparent and in part pointed out below. It should be understood that the various embodiments may be implemented individually or in combination with one another. It should also be understood that the detailed description and drawings, while indicating certain exemplary embodiments, are intended for purposes of illustration only and should not be construed as limiting the scope of the present disclosure.
Like reference symbols indicate like elements or features throughout the drawings.
Illustrative embodiments of the present disclosure are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will be appreciated that in the development of any actual embodiment, numerous implementation-specific decisions must be made to achieve specific goals, such as performance objectives and compliance with system-related, business-related and/or environmental constraints. Moreover, it will be appreciated that such development efforts may be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.
An exemplary motor and controller assembly for a horizontal axis washing machine, i.e., front loader washing machine, according to various embodiments of the present disclosure is illustrated in
In various embodiments, the electric motor 102 is a variable speed controlled induction motor. It should be understood, however, that other motor types, including brushless permanent magnet (BPM) and switched reluctance (SR) motors, can be employed without departing from the scope of the present disclosure. Furthermore, while the embodiment of
In contrast to known washing machines having a motor controller positioned remotely from an electric motor, the controller 104 of
Although
One example of a suitable motor and controller assembly for use in the horizontal axis washing machine 200 of
As shown in
The endshield 114 can be mounted to the stator 108 using any suitable fastening means. For example, the stator 108 can include bores 117 through which threaded rods (not shown) are inserted. The threaded rods can extend beyond the ends of the stator 108 and through mounting apertures 119 in both endshields 114 and 116. Threaded fasteners, e.g., nuts, (not shown) can then be threaded on opposing ends of the threaded rod to couple both endshields 114 and 116 directly to the stator 108. The controller 104 can then be mounted directly to the endshield 114 using any suitable coupling means. For example, as illustrated in
Alternatively, the controller 104 can be directly coupled to the endshield 114 using any other suitable coupling means or fasteners such as nuts and bolts, snap fasteners, rivets, etc. Still further, in various embodiments, the controller housing base 120a can be integrally formed with the endshield 114 to directly couple the controller 104 to the endshield 114.
With reference again to
As exemplarily illustrated in
The heat sink 109 is provided for dissipating heat generated by the heat producing component 122a (and possibly other components 122). In various exemplary constructions, the heat producing component 122a is thermally coupled to the heat sink 109 after the circuit board 118 is attached to the housing base 120a. The housing cover 120b is then attached to the housing base 120a to protect the circuit board 118 and its various components 122. Alternatively, as described above, in various embodiments, the controller 104 is a modular subassembly that is assembled separately from the motor 102 and then subsequently coupled to the motor endshield 114. Thus, the base 120a, the circuit board 118 and the cover 120b can be assembled to form the controller 104 that is then coupled to the endshield 114. The heat sink 109 can then be thermally coupled to the heat producing component 122a subsequent to mounting the controller 104 to the motor 102.
The heat producing component 122a can be thermally coupled to the heat sink 109 in any suitable manner. For example, the component 122a can be physically attached to the heat sink 109 using fasteners and/or adhesives. Additionally, thermal paper may be provided between the heat producing component 122a and the heat sink 109 to enhance the transfer of heat therebetween. As shown in
It should be noted that, in the embodiment of
Although the heat sink 109 positioned on the motor 102 and external to the controller housing 120 has been described above in connection with the motor and controller assembly 100 for a horizontal axis washing machine, it should be understood that these heat sink features can be applied to other electric motor designs and applications without departing from the scope of the present disclosure.
The insulating shield 120a′ can provide one or more of various types of insulation between the circuit board 118 and the endshield 114. For example, the insulating shield 120a′ can be an electrical insulator to prevent arcing between the circuit board 118 and endshield 114. Generally, the controller 104, i.e., the circuit board 118, operates to control the application of voltages to the motor 102. Accordingly, various components of the circuit board 118 have high operating voltage, e.g., 120 volts, such as high voltage component 130. Additionally, the motor 102, i.e., the endshield 114, is generally grounded at a ground reference potential. Thus, arcing could occur between the high voltage components, e.g., high voltage component 130, on the circuit board 118 and the endshield 114. The insulating shield 120a′ provides electrical insulation to prevent such arcing. To provide such electrical insulation, the insulating shield 120a′ can be fabricated from any suitable electrical dielectric, or electrically insulative, material such as various plastics, resins, fiber filled polymer, fiberglass, etc.
The insulating shield 120a′ can also be a thermal insulator to prevent undesirable exchange of heat between the circuit board 118 and the endshield 114. For example, transfer of heat generated by the motor 102 during operation to the circuit board 118 can damage or undesirably affect functionality of the electronics, e.g., high temperature component 122a and high voltage component 130, of the circuit board 118. To provide the thermal insulation the insulating shield 120a′ can be fabricated from any suitable thermally insulative material such as various plastics, resins, fiber filled polymer, fiberglass, etc.
Still further, the insulating shield 120a′ can be an electro-magnetic interference (EMI) insulator that shields the circuit board 118 from adverse affects of electromagnetic fields created by the motor 102 during operation, and vice-versa. To provide the EMI insulation described above the insulating shield 120a′ can be fabricated from any suitable EMI insulative material such as various plastics, resins, fiber filled polymer, fiberglass, etc. Thus, the insulating shield 120a′ can provide electrical insulation, thermal insulation, EMI insulation or any combination thereof.
To provide additional electrical, thermal and/or EMI insulation between the circuit board 118 and the endshield 114, in various other embodiments, the insulating shield 120a′ can include a insulative layer 131 comprising an insulative fabric, potting compound, conformal coating or any other suitable insulating coating. The insulative layer 131, i.e., insulative fabric, potting compound, conformal coating, etc., is fabricated from any suitable electrically, thermally and/or EMI insulative material such as various plastics, resins, fiber filled polymer, fiberglass, etc. Furthermore, to provide additional electrical, thermal and/or EMI insulation between the circuit board 118 and the endshield 114, in various other embodiments, the insulating shield 120a′ can include stand-off bosses 132. The stand-off bosses 132 provide additional physical separation between the circuit board 118 and the motor and endshield 102 and 114. The height of the stand-off bosses 132, e.g., distance of physical separation, can be any height suitable to provide a desired amount of electrical, thermal and/or EMI insulation.
As exemplarily illustrated in
In various exemplary constructions, the circuit board 118 is coupled directly with the heat sink 120b′ so that the heat producing component 122a is thermally coupled to the heat sink 120b′. The circuit board 118 can be coupled to the heat sink 120a′ using snaps, screws, rivets, glue or any other suitable fastening means. The heat sink 120b′ and circuit board 118 assembly is then coupled to the insulating shield 120a′ to form the modular controller 104. The heat sink 120b′ and circuit board 118 assembly can be coupled to the insulating shield using any suitable fastening means, such as snap connectors, screws, rivets, glue, etc. The assembled modular controller 104 is then directly coupled to the endshield 114 such that the modular controller 104 is integrally coupled to the endshield 104.
The heat producing component 122a can be thermally coupled to the heat sink 120b′ in any suitable manner. For example, physical contact can be made between the component 122a and the heat sink 120b′ when the heat sink 120b′ is coupled with circuit board 118. Additionally, thermal paper may be provided between the heat producing component 122a and the heat sink 109 to enhance the transfer of heat therebetween. Furthermore, in various implementations, the heat sink 120b′ can include open sides 134 and/or one or more windows 136 to provide an ‘open’ construction of the modular controller 104. The ‘open’ construction allows air to flow through the controller 104 to provide additional cooling to the circuit board components 122 and 130.
In various embodiments, after the circuit board 118 is coupled to the heat sink 120b′, screws (not shown) are inserted through the apertures 126 in the heat sink 120b′ and the insulative shield 120a′. The screws are then threaded into the threaded apertures 128 of the endshield 114 to integrally mount the modular controller 104 to the endshield 114. By integrally mounting the modular controller 104 to the endshield 114, any force or stress that is exerted on the modular controller 104 will be transferred directly to the endshield 114 and not imparted on the circuit board 118 within the modular controller 104. For example, forces or stresses from handling the motor and controller assembly 100 using the modular controller as a handle will be distributed, via the screws connecting the modular controller 104 to the endshield 114, directly to the endshield 114. Accordingly, such forces and stresses will not be applied to the circuit board 118, thereby preventing the circuit board 118 from damage resulting from movement, flexing, vibration, etc. of circuit board 118.
In some implementations, one of the screws used to integrally couple the modular controller 104 to the endshield 114, as described above, is utilized to electrically ground the circuit board 118 to the endshield 114.
To provide additional protection against damage to the circuit board 118, due to forces or stresses applied to the modular controller 104, in some embodiments, the endshield 114 is fabricated to include a controller receiving wall 131. The controller receiving wall extends substantially orthogonally from the controller-end of the endshield 114, e.g., from the perimeter of the controller-end, and forms a reservoir in which the modular controller 104 is seated when integrally coupled to the endshield 114. More specifically, the perimeter shape and dimensions of the controller receiving wall 131 are such that the insulating shield 120a′ fits snuggly within the controller receiving wall 131 when the modular controller 104 is integrally coupled to the endshield 114.
The controller receiving wall 131 has a height H that extends along the sides of the insulating shield 120a′, thereby adding support to the sides of the modular controller 104. Accordingly, the controller receiving wall 131 will provide added support to the modular controller to displace forces and stresses to the endshield 114. Additionally, controller receiving wall 131 provides sufficient surface area that the motor and controller assembly 100 can be handled by directly grasping the controller receiving wall 131. Thus, no force or stress would be applied to the modular controller 104 during such handling of the motor and controller assembly 100. The height H of the controller receiving wall 131 can be any suitable height, for example, in various embodiments, the height H is approximately ¼ of an inch, ½ of an inch, ¾ of an inch, etc.
Referring particularly to
In such embodiments, the insulative shield can include a hood portion 133. The hood 133 substantially covers and provides physical protection and insulative protection, e.g., electrical, thermal and/or EMI insulation, for the circuit board second portion 118b.
Referring now to
Referring again to
Additionally, those skilled in the art will recognize that various changes can be made to the exemplary embodiments and implementations described above without departing from the scope of the present disclosure. Accordingly, all matter contained in the above description or shown in the accompanying drawings should be interpreted as illustrative and not in a limiting sense.
This application is a continuation-in-part of U.S. patent application Ser. No. 11/208,688 filed on Aug. 22, 2005.
Number | Date | Country | |
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Parent | 11208688 | Aug 2005 | US |
Child | 11601060 | Nov 2006 | US |