Abstract:
The present disclosure relates to miniaturized motor assembly for use in an appliance, for example, an ice maker for a commercial or residential refrigerator. The miniaturized motor assembly includes an electric motor, such as a permanent magnet direct current (PMDC) motor, and a printed circuit board operable to control power to the electric motor, wherein the printed circuit board is connected to the motor as a component of the assembly. At least one electrically-conductive connection device acts as a terminal, providing multiple points of contact between the printed circuit board and the motor, forming both an improved, reliable mechanical connection and an effective electrical connection between the circuit board and the motor. Use of the electrically-conductive connection device of the present disclosure eliminates the need for tedious and inconsistent soldering connections, while providing multiple points of contact and improved electrical contact over other forms of connecting devices.

Description:
[0001]    This application claims priority to U.S. Provisional Application Ser. No. 62/345,058 filed Jun. 3, 2016, which is incorporated in its entirety herein. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates generally to a miniaturized motor assembly. In particular, the present disclosure relates to a miniaturized motor assembly including a permanent magnet direct current (PMDC) motor secured to a printed circuit board (PCB) using an electrically conductive connection device. The present electrically conductive connection device provides multiple points of contact between the motor and the PCB, offering both improved electrical and mechanical integrity between the PBC and the motor. The present device is useful for designing a miniaturized motor assembly required in limited spaces, such as in the interior of appliances. 
       BACKGROUND 
       [0003]    It is, of course, generally known to create a motor assembly using an electric motor, such as a permanent magnet direct current (PMDC) motor connected to a printed circuit board (PCB) for generating power to the motor. In particular, miniaturized motor assemblies are useful in many forms of both commercial and household appliances, including, but not limited to, ice makers, automatic dishwashing machines, laundry machines, vending machines and other appliances. 
         [0004]    The conventional approach of attaching a printed circuit board to a preferred motor, while maintaining the desired electrical connection, is by soldering. The issue, however, is that soldering is a difficult process, requiring expert technique. Further, soldering can be a slow and inconsistent process, as accuracy is dependent on the skill of the person performing the soldering work. Additionally, soldering itself results in fumes which can be unpleasant for those performing the soldering. 
         [0005]    Other types of fasteners may also be used to connect a PCB to a motor, including screws optionally constructed from electrically conductive material. However, the screws may not provide the close, compact arrangement between the PCB and the motor due to the shank structure of the screw, or offer the improved mechanical and electrical connection proposed by the multi-point contacts of the present device. 
         [0006]    A need, therefore, exists for an improved device and method for securing a printed circuit board to a desired motor to create a compact miniaturized motor assembly. Specifically, a need exists for an improved device and method for securing a printed circuit board to a motor without soldering as the primary connection, as well as provide consistent electrical and mechanical connections. 
         [0007]    A need further exists for an improved device and method for securing a printed circuit board to a motor to create a compact arrangement for a miniaturized motor assembly. 
         [0008]    Moreover, a need exists for an improved device and method fur securing a printed circuit board to a motor creating at least one improved electrical connection through multiple points of contact between the PCB and the motor. 
         [0009]    Further, a need exists for an improved device and method for creating an improved mechanical connection through multiple points of contact between the PCB and the motor. 
         [0010]    A need further exists for an improved device and method providing an easier, faster and more consistent connection between a PCB and a motor. 
         [0011]    Further, a need exists for an improved device and method for providing repeatable electrical connections between a PCB and a motor for use in constructing a miniaturized motor assembly. 
       SUMMARY 
       [0012]    The present invention relates to miniaturized motor assembly for use in an appliance, for example, a washing machine, dishwasher or an ice maker for a commercial or residential refrigerator. The miniaturized motor assembly includes an electric motor, such as a permanent magnet direct current (PMDC) motor, and a printed circuit board operable to control power to the electric motor, wherein the printed circuit board is connected to the motor as a component of the assembly. At least one electrically-conductive connection device acts as a terminal, providing multiple points of contact between the printed circuit board and the motor, forming both an improved, reliable mechanical connection and an effective electrical connection between the circuit board and the motor. Use of the type electrically-conductive connection device of the present disclosure eliminates the need for tedious and inconsistent soldering connections, while providing multiple points of contact and improved electrical contact over other forms of connecting devices. Additionally, use of the present connection device simplifies assembly of the overall miniaturized motor assembly. 
         [0013]    To this end, in an embodiment of the present disclosure, a motor assembly is provided. The motor assembly includes a motor having an end component, a printed circuit board configured to operate the motor, at least one electrically-conductive connection device for securing the printed circuit board to the end component of the motor, the connection device comprising: a first side and a second side, wherein the first side and the second side connect to one another along an outer edge, wherein the first side and the second side are positioned perpendicular to one another, the first side further including a threaded aperture, wherein the threaded aperture is designed for receiving a fastener there through; and, wherein the connection device provides multiple points of electrical and mechanical contacts between the motor and the printed circuit board. 
         [0014]    In yet another embodiment, a compact miniaturized motor assembly is provided. The compact miniaturized motor assembly includes a motor with an end having an outer surface and a center shaft projecting therefrom, a printed circuit board configured to operate the motor, a first electrically-conductive connection device and a second electrically-conductive connection device, each connection device for securing the printed circuit board to the end surface of the motor, each connection device comprising: a first side and a second side, wherein the first side and the second side connect to one another along an outer edge, wherein the sides are positioned perpendicular to one another, the first side further includes a threaded aperture, wherein the threaded aperture is designed for receiving a fastener; and, wherein the connection devices provide multiple points of electrical and mechanical contacts between the motor and the printed circuit board. 
         [0015]    An improved method for securing a printed circuit board to a motor creating a miniature motor assembly is also provided. The method includes the steps of providing a motor having an end and a center shaft projecting therefrom, providing a printed circuit board configured to operate the motor, positioning a first electrically-conductive connection device and a second electrically-conductive connection device onto the end of the motor and offset from each other, each connection device comprising: a first side and a second side, wherein the first side and the second side connect to one another along an outer edge, wherein the sides are positioned perpendicular to one another, the first side further includes a threaded aperture, wherein the threaded aperture is designed for receiving a fastener for securing the printed circuit board to the motor, and, securing the printed circuit board to the end of the motor using the first and second connection devices, wherein the connection devices provide multiple points of electrical arid mechanical contacts between the motor and the printed circuit board. 
         [0016]    It is, therefore, an advantage and objective of the present disclosure to provide motor assembly, including a compact miniaturized motor assembly having an improved connection device for securing a printed circuit board to a motor without soldering. 
         [0017]    Moreover, it is an advantage and objective of the present disclosure to provide a electrically-conductive connection device for securing a printed circuit board to a motor while providing an improved mechanical connection. 
         [0018]    It is yet another advantage and objective of the present disclosure to provide an electrically-conductive connection device for securing a printed circuit board to a motor that also provides multiple contact points for improved mechanical and electrical connection between the printed circuit board and the motor. 
         [0019]    It is yet a further advantage and objective of the present disclosure to provide an electrically-conductive connection device that provides easier, faster and more consistent connections between a printed circuit board and a motor. 
         [0020]    It is another advantage and objective of the present disclosure to provide a method for securing a printed circuit board to a motor using an electrically-conductive connection device, thereby providing both an improved electrical and mechanical connection between the printed circuit board and the motor. 
         [0021]    Additional features and advantages of the present invention are described in, and will be apparent from, the detailed description of the presently preferred embodiments and from the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    The drawing figures depict one or more implementations in accord with the present concepts, by way of example only, not by way of limitations. In the figures, like reference numerals refer to the same or similar elements. 
           [0023]      FIG. 1  illustrates an exploded view of a miniaturized motor assembly in accordance with the present disclosure; 
           [0024]      FIG. 2  illustrates a partially exploded view of the miniaturized motor assembly in accordance with the present disclosure; 
           [0025]      FIG. 3  illustrates a perspective view of the completely assembled miniaturized motor assembly of the present disclosure; and, 
           [0026]      FIG. 4  illustrates a perspective view of an electrically-conductive connection device for use in a miniaturized motor assembly of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    The present invention relates to a miniaturized motor assembly  10  for use primarily in appliances, for example, refrigerator ice making machines, dishwashing machines, laundry machines, and other household and commercial appliances. All of these appliances typically have limited interior space; thus, it is advantageous to use a compact, miniaturized motor assembly in the operation of these appliances. The present invention provides a connection device for not only efficiently and easily connecting a printed circuit board (PCB) to a permanent magnet DC (PMDC) motor, but also provides at least one, and preferably multiple electrical contact points between the PCB and the PMDC motor, thereby offering an improved electrical connection. Additionally, the multiple contact points offered by the present terminal tab connection device also provide an improved mechanical connection between the PCB and its PMDC motor. 
         [0028]    Now referring to the figures, wherein like numerals refer to like parts,  FIG. 1  illustrates an exploded view of an exemplary embodiment of a motor assembly  10 , including a miniaturized motor assembly for use in the operation of an appliance or component of an appliance, such as an icemaker for a refrigerator. Specifically, the present miniaturized motor assembly  10  is useful in appliances having limited internal space, including ice makers, refrigerators, automatic dishwashers, and the like. The miniaturized motor assembly  10  typically includes a direct current motor  12 , which is connected to a printed circuit board (PCB)  14 . 
         [0029]    Direct current (DC) motors are well-known and commonly-used motors for operating small machine/appliance applications, such as a washing machine, and/or appliance components, such as an icemaker in a refrigerator. Additionally, because of the limited interior space of most appliances for its motor and other operating features, it is advantageous to have a compact motor assembly. In the present disclosure, a permanent magnet direct current (PMDC) motor  12  is used. The present motor  12  also shows a shaft  18 ; however, other known components of the motor, including a rotor, stator (or armature), brushes, and a plurality of magnets/windings, etc., are not shown. The motor  12  of the present assembly includes an end component  16 , preferably constructed from plastic, having an outer surface  16   a  for securing a printed circuit board  14  thereto using the connection device  20  of the present disclosure. 
         [0030]      FIG. 1  illustrates a typical printed circuit board (PCB)  14  used for operation of the motor  12  in the present assembly  10 . The PCB is of an exemplary type, as is known in the art. The conventional approach of attaching a PCB to a motor is by soldering. However, soldering the PCB  14  to the motor  12  can be not only tedious, but inaccurate, often resulting in an unsatisfactory mechanical and electrical connections between the PCB and the motor. Furthermore, accurate soldering takes skill and is time-consuming. 
         [0031]    The present disclosure, however, provides an improved connection device  20 , generally in the form of a tab, for securing the PCB  14  to the motor  12 . The shape of the present connection device  20 , which may also be referred to as a terminal tab connection device, further provides multiple points of contact resulting improved electrical and mechanical contact between the printed circuit board  14  and the motor  12 . The terminal tab connection device  20  provides a direct contact point between the PCB and the motor terminals holding the brush mechanism (not shown) of the motor, which provides improved electrical connection. 
         [0032]    As shown in  FIGS. 1 and 4 , the connection device  20  of the present disclosure has a generally L-shaped configuration. Specifically, the connection device  20  includes a first terminal side  22  connected by an edge  24  to a second side  26 , wherein the first side and the second side are positioned at a 90 degree angle or perpendicular to one another. The first terminal side  22 , which acts as a screw terminal, includes a threaded opening or aperture  28  there through. A second, semicircle shaped opening  29  may also be included on the first terminal side  22  and opposite to the aperture  28 . The second, semicircle opening  29  may accommodate a second fastener, as needed. 
         [0033]    The threaded aperture  28  is designed to receive a securing element or fastener, such as a screw  30  for connecting the PCB  14  to the motor  12  ( FIGS. 1 and 2 ). The surface  22   a  of the first side  22  provides a point of contact at a solder pad  15  shown on the outer side or component side  14   a  of the PCB on the inner side  14   b  of the PCB, which connects with the first terminal side  22 . Thus, the surface  22   a  of the first side  22  of the connection device  20 , the threaded aperture  28 , the screw  30  engaged within the threaded aperture, and the screw head  30   a  are all points of contact, providing improved, multiple points of electrical and mechanical contact between the PCB  14  and the motor  12 . 
         [0034]    Additionally, when the terminal tab connection device  20  is positioned on the end component  16 , specifically on the end surface  16   a  of the motor  12 , the second side  26  of the terminal tab connection device  20  extends through the end surface and into the interior  12   a  of the motor. When positioned, the second side  26  of the connection device  20  contacts the brush holder (not shown), which houses the brush mechanism, which in turn contacts the armature assembly (not shown) of the motor  12 . The entire terminal tab connection device  20  (one negative terminal and one positive terminal) is fitted into the plastic end component  16  of the motor  12  ( FIGS. 2 and 3 ). The end component  16  provides not only a mechanical connection between the PCB and the motor, but more importantly, insulates the two voltage potential (negative and positive terminals) from shorting as electrical voltage is introduced to the terminals  20  via the PCB  14  providing power to the motor  1 . 2 . 
         [0035]    In an embodiment of the present disclosure, at least one electrically-conductive connection device  20  is used to connect the PCB  14  to the motor  12 . In a preferred embodiment of the present disclosure, the assembly  10  includes at least two electrically-conductive connection devices  20 . As shown in  FIGS. 1 and 2 , the connection devices  20  are separately embedded within an end component  16  of the motor  12 , specifically within a slight indentation space  17  on the outer surface  16   a  of the end component. When the first terminal side  22  of the connection device  20  is placed within the indentation space  17 , the second side  26  of the connection device is inserted into an opening (not shown) in the end component  16 , such that the second side projects into the interior  12   a  of the motor  12 . In this manner, when positioned, the first terminal side  22  of the connection devices  20  flush with the outer surface  16   a  of the end component  16  of the motor  12 . Thus, when the printed circuit board  14  is secured to motor  12 , the printed circuit board solder pad  15  is positioned directly on top of the first terminal side  22  thus making a direct contact. When the screw  30  is inserted into the threaded aperture  28  and tightened, a very efficient electrical connection between the PCB  14  through its copper solder pad  15  and the first terminal side  22  occurs. This arrangement results in the improved multiple point electrical and mechanical contacts between the printed circuit board  14  and the motor  12 . 
         [0036]    As shown in  FIGS. 1 and 2 , in a preferred embodiment, the terminal tab connection devices  20  are designed to be positioned offset from one another and also off-center from the center axis opening  18   a  for the motor shaft  18  on the end component  16  of the motor  12 . A printed circuit board  14  is typically attached to a motor using fasteners, such as screws placed in holes (not shown) on either side of the center motor shaft  18 . In the present disclosure, the connection devices  20  are positioned diagonally opposed from one another, and off-center to the center axis opening  18   a  for the motor shaft  18 . The motor screws  30  used to connect the PCB  14  to the end component  16  of the motor  12  through the connection devices  20 , are also off-center from the motor shaft  18 . This offset arrangement of the connection devices  20  and the motor screws  30  enhances the mechanical strength of the arrangement, including better structural holding force and structural integrity to PCB  14  in relation to its plane and the motor  12 . 
         [0037]    Advantages offered by the present electrically-conductive connection device  20  in the miniaturized compact motor assembly  10  include: repeatable, consistent and reliable electrical connections, which are easier to apply and less hazardous than solder joints and connections. The present electrically-conductive connection device  20  also provides multiple contact points between the PCB and motor, providing improved electrical and mechanical connections between the PCB and motor. 
         [0038]    An improved method for securing a printed circuit board  14  to a motor  12  creating a miniature motor assembly  10 , is also provided. The method provides multiple points of electrical and mechanical contacts between a motor and a printed circuit board. The method includes the steps of providing a motor  12  having an end  16  and a center shaft  18  projecting therefrom, providing a printed circuit board  14  configured to operate the motor. At least a first electrically-conductive connection device  20  and a second electrically-conductive connection device  20  are secured to the end  16  of the motor  12  and offset from each other. The electrically-conductive connection devices  20  each include a threaded aperture  28 , wherein the threaded aperture is designed for receiving a fastener  30  for securing the printed circuit board  14  to the motor  12 . Securing the printed circuit board  14  to the end  16  of the motor  12  using the first and second connection devices  20 , provide multiple points of electrical and mechanical contacts between the motor and the printed circuit board. Advantages of the present method includes providing improved, reliable and repeatable electrical and mechanical connections between the printed circuit board  14  and motor  12  without the need for soldering. 
         [0039]    It should be noted that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the present invention and without diminishing its attendant advantages. Further, references throughout the specification to “the invention” are non-limiting, and it should be noted that claim limitations presented herein are not meant to describe the invention as a whole. Moreover, the invention illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein.