Patent Publication Number: US-2022231565-A1

Title: Integrated magnetic shield and bearing holder

Description:
BACKGROUND 
     Some known vehicles include an electric power steering (EPS) system that helps drivers by augmenting an amount of effort needed to turn a steering wheel. Known EPS systems include one or more sensors that detect a force applied to the steering wheel, an electric motor configured to apply assisting force, and a control unit that actuates the electric motor based on the force detected by the sensors. Such sensors and electric motors may include or use one or more magnets to function. However, such magnets may form magnetic fields that interfere with other magnetic fields, emissions, radiations, and/or inductions of or in the EPS system, potentially compromising or reducing an operational reliability of the sensors, electric motor, and/or control unit. Known methods and systems for addressing this issue are generally more complicated, difficult to assemble, and/or expensive. Moreover, at least some packaging constraints, such as size and/or access constraints, may further exacerbate the deficiencies of known methods and systems. 
     SUMMARY 
     Examples of the disclosure simplify the assembly process and reduce the impact of known packaging constraints. In one aspect, a bearing holder unit is provided for use with an electric power steering apparatus. The bearing holder unit includes a shaft portion and a cover portion extending radially outward from the shaft portion. The shaft portion includes an inner wall defining a channel and a ledge extending radially inward from the inner wall. The cover portion includes a first layer, a second layer extending substantially parallel to the first layer, a magnetic shield extending between the first layer and the second layer, and an outer wall extending from the first layer and/or the second layer such that a space is defined between the outer wall and the shaft portion. The cover portion includes one or more retainers coupled to the magnetic shield to restrict movement of the magnetic shield relative to the first layer and/or the second layer. 
     In another aspect, a system is provided for producing an integrated magnetic shield and bearing holder. The system includes a stamping press configured to form a magnetic shield including one or more first retainers, a mold defining a cavity, and one or more rods configured to position the magnetic shield in the cavity such that molding material is configured to flow above the magnetic shield and below the magnetic shield. The molding material forms a shaft portion and a cover portion of the integrated magnetic shield and bearing holder. The cover portion includes a first layer, a second layer extending substantially parallel to the first layer, the magnetic shield extending between the first layer and the second layer, and an outer wall extending from the first layer and/or the second layer. The first layer and/or the second layer includes one or more second retainers. 
     In yet another aspect, a method is provided for forming an integrated magnetic shield and bearing holder. The method includes forming a magnetic shield including one or more first retainers, positioning the magnetic shield in a cavity defined by a mold, forming a shaft portion and a cover portion of the integrated magnetic shield and bearing holder, and extracting the integrated magnetic shield and bearing holder from the cavity defined by the mold. The cover portion includes a first layer, a second layer extending substantially parallel to the first layer, the magnetic shield extending between the first layer and the second layer, and an outer wall extending from the first layer and/or the second layer. The first layer and/or the second layer includes one or more second retainers. 
     Various refinements exist of the features noted in relation to the above-mentioned aspects. Further features may also be incorporated in the above-mentioned aspects as well. These refinements and additional features may exist individually or in any combination. For instance, various features discussed below in relation to any of the illustrated examples may be incorporated into any of the above-described aspects, alone or in any combination. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Features, aspects, and advantages of the present disclosure will become better understood when the following Detailed Description is read with reference to the accompanying drawings in which like reference characters represent like elements throughout, wherein: 
         FIG. 1  is a schematic view of an example power steering system; 
         FIG. 2  is a schematic cross-sectional view of an example motor that may be used with a power steering system, such as the power steering system shown in  FIG. 1 ; 
         FIG. 3  is a perspective view of an example integrated magnetic shield and bearing holder that may be used with a motor, such as the motor shown in  FIG. 2 ; 
         FIG. 4  is a cross-sectional view of the integrated magnetic shield and bearing holder shown in  FIG. 3 ; 
         FIG. 5  is a perspective view of an example magnetic shield that may be used with a bearing holder, such as the integrated magnetic shield and bearing holder shown in  FIGS. 3 and 4 ; 
         FIG. 6  is a block diagram of an example system that may be used to manufacture an integrated magnetic shield and bearing holder; 
         FIG. 7  is a flowchart of an example method of manufacturing an integrated magnetic shield and bearing holder; 
         FIG. 8  is an upper perspective view of another example integrated magnetic shield and bearing holder that may be used with a motor, such as the motor shown in  FIG. 2 ; 
         FIG. 9  is a lower perspective view of the integrated magnetic shield shown in  FIG. 8 ; 
         FIG. 10  is a cross-sectional view of the integrated magnetic shield shown in  FIGS. 8 and 9 ; 
         FIG. 11  is a perspective view of an example magnetic shield that may be used with a bearing holder, such as the integrated magnetic shield and bearing holder shown in  FIGS. 8-10 ; 
         FIG. 12  is a lower plan view of yet another example integrated magnetic shield and bearing holder that may be used with a motor, such as the motor shown in  FIG. 2 ; 
         FIG. 13  is a cross-sectional view of the integrated magnetic shield shown in  FIG. 12 ; and 
         FIG. 14  is a perspective view of an example magnetic shield that may be used with a bearing holder, such as the integrated magnetic shield and bearing holder shown in  FIGS. 12 and 13 . 
     
    
    
     Although specific features of various examples may be shown in some drawings and not in others, this is for convenience only. Any feature of any drawing may be referenced and/or claimed in combination with any feature of any other drawing. 
     DETAILED DESCRIPTION 
     The present disclosure relates to power systems and, more particularly, to an integrated magnetic shield and bearing holder. Examples described herein integrate a magnetic shield within a bearing holder. This allows a user to handle both the magnetic shield and the bearing holder simultaneously. An example integrated magnetic shield and bearing holder may include a shaft portion and a cover portion extending radially outward from the shaft portion. The magnetic shield may be integrated into the cover portion by extending a first layer above and a second layer below the magnetic shield. The cover portion includes one or more retainers coupled to the magnetic shield to restrict movement of the magnetic shield relative to one or more of the first layer or the second layer. Examples of the disclosure simplify the assembly process and reduce the impact of known packaging constraints, such as size and/or access constraints. 
     Certain terminology is used in the present disclosure for convenience and reference only and not in a limiting sense. For example, the terms “lower,” “upper,” “downward,” “upward,” “above,” and “under,” “vertical,” “horizontal,” and the like designate directions in relation to the perspective shown in the drawings. One of ordinary skill in the art would understand and appreciate that the example methods and systems described herein may be used in various orientations. Moreover, some “spaces,” “cavities,” and “openings” described herein may be interpreted to include a rim portion, an edge, or other physical feature that defines such “spaces,” “cavities,” openings.” 
       FIG. 1  shows a steering unit  100  that may be used to steer or maneuver a vehicle (not shown). The steering unit  100  includes a steering wheel  110 , at least one steering gear  120 , and a steering shaft  130  extending between the steering wheel  110  and steering gear  120 . The steering wheel  110  is rotatable about a steering axis  132 . The steering wheel  110  may be rotated (for example, by a driver or operator) to provide a steering input. 
     The steering shaft  130  is coupled to the steering wheel  110  such that the steering shaft  130  is configured to rotate with the steering wheel  110  (for example, as the steering wheel  110  rotates). In this manner, the steering input at the steering wheel  110  may be transmitted to the steering gear  120  via the steering shaft  130  (for example, in the form of a turning force or torque). The steering gear  120  is configured to covert a rotational motion of the steering shaft  130  into a linear motion. The steering gear  120  may be, for example, a pinion gear (for example, in a rack-and-pinion configuration) or a worm gear (for example, in a recirculating ball configuration). Alternatively, the steering gear  120  may be any gear used in any configuration that enables the steering unit  100  to function as described herein. 
     As shown in  FIG. 1 , the steering gear  120  may be coupled to one or more tie rods  140  extending between the steering gear  120  and one or more wheel assemblies  150 . The tie rods  140  are coupled to the steering gear  120  such that the tie rods  140  are configured to move with the steering gear  120 . In this manner, the steering input at the steering gear  120  may be transmitted to the wheel assemblies  150  via the tie rod  140  (for example, in the form of a push force or a pull force). 
     The steering unit  100  includes a power steering assembly  160  that assists the driver in steering or maneuvering the vehicle. In some examples, the power steering assembly  160  includes one or more sensors  170  configured to detect one or more input parameters, a control unit  180  configured to determine an assisting force based on the input parameters, and an electric motor  190  configured to apply the assisting force to the steering shaft  130  and/or steering gear  120 . The electric motor  190  may generate a torque, for example, to provide the assisting force, which may be applied to allow the driver to steer or maneuver the vehicle with greater ease (for example, using a force smaller than that without the assisting force). Example input parameters may include, without limitation, a position (for example, rotation angle), a torque, and/or an angular velocity of the steering wheel  110 , steering gear  120 , and/or steering shaft  130 . 
       FIG. 2  shows an example motor  200  (for example, electric motor  190 ) that may be used to apply an assisting force to the steering shaft  130  and/or steering gear  120 . In some examples, the motor  200  includes a housing  210  that includes a side wall  212  and an end portion  214  at a lower end thereof. The side wall  212  may have a substantially cylindrical configuration and define an opening at an upper end opposite the lower end. The end portion  214  may have a generally planar configuration and define an opening  216  therethrough. 
     The housing  210  is sized and/or configured to house or accommodate a rotor  220  and a stator  230  therein. For example, the stator  230  may be positioned in a space defined by the side wall  212  such that the side wall  212  extends circumferentially about the stator  230 . In some examples, the stator  230  is fixed or securely coupled to an inner surface of the side wall  212 . As shown in  FIG. 2 , the stator  230  may include at least one stator core and a plurality of coils extending circumferentially about the stator core. In some examples, the coils are helically wound about the stator core. 
     The rotor  220  may be positioned radially inward of and spaced from the stator  230  such that the stator  230  extends circumferentially about the rotor  220 . The rotor  220  is rotatable about a center axis  236 . As shown in  FIG. 2 , the rotor  220  may include a shaft  242  extending along the center axis  236 , at least one rotor core  244  coupled to the shaft  242 , and a plurality of rotor magnets  246  coupled to the rotor core  244 . In some examples, the rotor core  244  is fixed to a radially outer surface of the shaft  242  and extends circumferentially about the shaft  242 , and the rotor magnets  246  are fixed to a radially outer surface of the rotor core  244  and extend circumferentially about the rotor core  244 . In this manner, the shaft  242 , rotor core  244 , and rotor magnets  246  may be configured to rotate about the center axis  236  together as a single unit, for example, the rotor  220 . To facilitate aligning the shaft  242  with the center axis  236 , a lower bearing  250  may be positioned axially on and extend circumferentially about a lower portion of the shaft  242 , and an upper bearing  252  may be positioned axially on and extend circumferentially about an upper portion of the shaft  242 . 
     In some examples, the end portion  214  defines a bearing pocket  254  configured to support the lower bearing  250 . The end portion  214  may include, for example, a center wall  256  defining the opening  216  and a side wall  258  extending upward from the center wall  256 . In some examples, an outer race of the lower bearing  250  is fixed or securely coupled to a radially inner surface of the side wall  258 . In this manner, the lower portion of the shaft  242  may extend through the opening  216  and be supported by the lower bearing  250 . 
     The motor  200  includes a bearing holder  260  configured to support the upper bearing  252 . The bearing holder  260  may extend, for example, across and/or adjacent to the opening defined at the upper end of the side wall  212 . The bearing holder  260  may be positioned to define, for example, a first side (for example, outside the housing  210 ) on which a control circuit, a power supply circuit, and/or a power conversion circuit may be positioned and a second side (for example, inside the housing  210 ) on which the stator  230 , rotor  220  may be positioned. 
     In some examples, the bearing holder  260  is securely coupled to the housing  210  and/or upper bearing  252 . An outer race of the upper bearing  252 , for example, may be fixed or securely coupled to a radially inner surface of the bearing holder  260 . The bearing holder  260  is configured to prevent or restrict the upper bearing  252  from wobbling with respect to the center axis  236 , even under vibration conditions, thereby enabling the motor  200  to exhibit stable rotation performance. In some examples, the bearing holder  260  is fabricated from a strong, rigid material, such as metal. 
       FIGS. 3 and 4  show an example integrated magnetic shield and bearing holder or bearing holder unit  300  (for example, bearing holder  260 ) including a shaft portion  310 . The shaft portion  310  has a substantially tubular configuration that allows the shaft  242  to rotate therein. As shown in  FIGS. 3 and 4 , the shaft portion  310  may include a side wall  312  (for example, a first or inner wall) defining a channel  314  through which the shaft  242  may extend. 
     The shaft portion  310  may include a ledge  316  extending radially inward from a radially inner surface of the side wall  312  and/or into the channel  314 . The ledge  316  is coupled to the side wall  312  to define a bearing pocket  318  (shown in  FIG. 4 ) therebetween. The side wall  312  and ledge  316  are sized and/or configured to house or accommodate the upper bearing  252  in the bearing pocket  318 . In some examples, the upper bearing  252  may be seated in the bearing pocket  318  such that an outer race of the upper bearing  252  is fixed or securely coupled to a radially inner surface of the side wall  312 . In this manner, the bearing holder unit  300  may be used to support and/or maintain a position of the upper bearing  252 . 
     The bearing holder unit  300  includes a cover portion  320  extending radially outward from the shaft portion  310 . The cover portion  320  has a diameter or width  322  that enables the cover portion  320  to extend across and/or adjacent to the opening defined at the upper end of the side wall  212  of the housing  210 . In some examples, the cover portion  320  includes one or more openings  323  (shown in  FIG. 3 ) defined axially therethrough (for example, parallel to the center axis  236 ) for use in coupling the bearing holder unit  300  to the housing  210  of the motor  200 . When the bearing holder unit  300  is coupled to the housing  210  (for example, using the openings  323 ), the shaft portion  310  is configured to support and/or maintain a position of the upper bearing  252  such that an upper portion of the shaft  242  may extend through the channel  314 . 
     The cover portion  320  includes a first layer  324  (shown in  FIG. 4 ), a second layer  326  (shown in  FIG. 4 ), and a magnetic shield  328  (shown in  FIG. 4 ; also shown in  FIG. 5 , described below) between the first layer  324  and second layer  326 . The first layer  324 , second layer  326 , and magnetic shield  328  may extend laterally or horizontally substantially parallel to each other. As shown in  FIG. 4 , the first layer  324  may extend over or at a higher elevation than the magnetic shield  328 , and the magnetic shield  328  may extend over or at a higher elevation than the second layer  326 . The first layer  324  and/or second layer  326  have a thickness that enables the cover portion  320  to restrict movement of the magnetic shield  328  while facilitating optimizing material reduction. In some examples, the first layer  324  has a thickness (for example, a first thickness) that is equal or substantially similar to a thickness of the second layer  326  (for example, a second thickness). Alternatively, the first layer  324  and second layer  326  may have different thicknesses. 
     The cover portion  320  may include one or more retainers or features  330  that enable the first layer  324 , second layer  326 , and/or magnetic shield  328  to be aligned with each other and restrict relative movement therebetween. In this manner, the features  330  may prevent or restrict rotation of the magnetic shield  328  relative to the first layer  324  and/or second layer  326 . Additionally, the features  330  may prevent or restrict translation of the magnetic shield  328  relative to the first layer  324  and/or second layer  326 . For example, the features  330  may restrict axial movement (for example, movement along the center axis  236 ) and/or lateral movement (for example, movement perpendicular to the center axis  236 ) of the magnetic shield  328  relative to the first layer  324  and/or second layer  326 . 
     As shown in  FIGS. 3 and 4 , the first layer  324  defines one or more first openings  332  extending therethrough, the second layer  326  defines one or more second openings  334  (shown in  FIG. 4 ) extending therethrough, and the features  330  of the magnetic shield  328  includes one or more projections or protrusions  336  extending from a base portion  338  (shown in  FIG. 4 ). Alternatively, the magnetic shield  328  may include one or more openings and the first layer  324  and/or second layer  326  may include one or more projections extending therefrom and through the openings. 
     The protrusions  336  may be sized and/or configured to extend at least partially through the first openings  332  and/or second openings  334 . The protrusions  336  may extend in a common or the same direction. In some examples, the protrusions  336  extend upward (for example, toward the first layer  324 ) and are aligned with the first openings  332  such that the protrusions  336  extend into and/or are seated in the first openings  332 . In some examples, the protrusions  336  do not extend upward beyond an upper surface of the first layer  324  to ensure that the bearing holder unit  300  conforms to an allotted packaging environment. Alternatively, at least one protrusion  336  may extend downward (for example, toward the second layer  326 ) and be aligned with at least one second opening  334  such that the protrusions  336  extends into and/or is seated in the second opening  334 . 
     The cover portion  320  may include an outer wall  340  (for example, a second wall) extending downward from the first layer  324  and/or second layer  326  such that a space  342  is defined between the outer wall  340  and the shaft portion  310 . The sizing and shape of the space  342  facilitates optimizing material reduction while restricting movement of the magnetic shield  328 . Additionally, a portion of the outer wall  340  may extend between the first layer  324  and/or second layer  326  to extend circumferentially at least partially about the magnetic shield  328 . 
       FIG. 5  shows the magnetic shield  328  free from the rest of the bearing holder unit  300 . The magnetic shield  328  is fabricated from at least one ferromagnetic metal (for example, iron, nickel, cobalt, steel), and has a thickness  344  that enables the magnetic shield  328  to obstruct or redirect a magnetic field. The thickness  344  of the magnetic shield  328  may be less than a thickness of the first layer  324  and/or the second layer  326 . In some examples, the thickness  344  is approximately 0.02 inches (in.) or 0.5 millimeters. Alternatively, the magnetic shield  328  may have any thickness  344  that enables the bearing holder unit  300  to function as described herein, including a thickness greater than or equal to the thickness of the first layer  324  and/or the second layer  326 . 
     The magnetic shield  328  defines an opening  346  extending therethrough. The magnetic shield  328  may be aligned such that the opening  346  is coaxial with the center axis  236  (for example, when integrated into a bearing holder unit  300  that is coupled to a housing  210 ). In some examples, the opening  346  has a diameter or width  348  that is the same as or substantially similar to a diameter of a radially outer surface (for example, an outer diameter) of the side wall  312  of the shaft portion  310  (for example, width  350 , shown in  FIG. 4 ). Additionally, the magnetic shield  328  may have a diameter or width  352  that is less than, but spans a substantial portion of, the width  322  of the cover portion  320 . As shown in  FIG. 5 , the magnetic shield  328  may have a substantially annular configuration. 
     In some examples, a base portion  338  of the magnetic shield  328  includes one or more features  330  at a radially outer surface that facilitate aligning the magnetic shield  328  relative to the first layer  324  and/or second layer  326 . For example, the radially outer surface of the base portion  338  may include a plurality of vertices  354  between which at least one chord portion  356  extends. The vertices  354  and/or chord portion  356  may engage a radially inner surface of the outer wall  340  such that rotation and/or translation of the magnetic shield  328  relative to the first layer  324  and/or second layer  326  is prevented or restricted. In some examples, the radially outer surface of the base portion  338  includes a pair of opposite chord portions  356 , each between a pair of opposite curved portions  358 . Alternatively, the base portion  338  may have any configuration that enables the bearing holder unit  300  to function as described herein. 
       FIG. 6  shows a system  400  for producing or manufacturing the bearing holder unit  300  including at least one metalworking tool or machine.  FIG. 7  shows a method  402  of producing or manufacturing the bearing holder unit  300  using the system  400 . In some examples, the magnetic shield  328  is formed at operation  410  (shown in  FIG. 7 ) using a stamping press  412  (shown in  FIG. 6 ). The stamping press  412  is configured to form the magnetic shield  328  from a sheet of ferromagnetic metal. The stamping press  412  may include, for example, a blanking punch and/or die  414  (shown in  FIG. 6 ) that forms a substantially planar piece having a circular or round configuration, and/or a piercing punch and/or die  416  (shown in  FIG. 6 ) that creates an opening  346  through the piece and/or sheet. Alternatively, the magnetic shield  328  may be formed using any other machine and/or device that enables the system  400  to function as described herein. For example, the opening  346  may be formed using a drill bit, a reamer, and/or a boring tool. 
     The magnetic shield  328  may be formed to include one or more features  330  (for example, protrusions  336 , vertices  354 , chord portions  356 ). For example, the blanking die  414  may be configured to form the magnetic shield  328  such that a radially outer surface of the base portion  338  includes at least one vertex  354  and/or chord portion  356 . Alternatively, the magnetic shield  328  may be formed such that the radially outer surface of the base portion  338  defines a round shape (for example, a circle). 
     In some examples, the stamping press  412  includes a dimple die  418  (shown in  FIG. 6 ) that forms or creates one or more protrusions  336 . Alternatively, one or more features  330  may be formed or created using any device or mechanism that enables the system  400  to function as described herein. 
     The magnetic shield  328  may be held or positioned at operation  420  (shown in  FIG. 7 ) using one or more posts or rods  422  (shown in  FIG. 6 ). For example, the rods  422  may include an upper rod  423  (shown in  FIG. 6 ) that applies a downward force  424  (shown in  FIG. 6 ) on the magnetic shield  328  at the protrusion  336  to support the magnetic shield  328  from above, and a lower rod  425  (shown in  FIG. 6 ) that applies an upward force  426  (shown in  FIG. 6 ) on the magnetic shield  328  at the protrusion  336  to support the magnetic shield  328  from below. 
     In some examples, the magnetic shield  328  and rods  422  are positioned in a cavity defined by a mold  428  (shown in  FIG. 6 ). In this manner, as a molding material (for example, a metal material) is channeled toward the cavity and/or the cavity is filled with the molding material, the molding material may flow around the magnetic shield  328  and rods  422  to form at operation  430  (shown in  FIG. 7 ) the shaft portion  310  and cover portion  320  of the bearing holder unit  300  such that the magnetic shield  328  is fabricated from a first material (for example, ferromagnetic metal), and the shaft portion  310 , first layer  324 , second layer  326 , and/or outer wall  340  are fabricated from a second material different from the first material. For example, the molding material flowing radially inward the magnetic shield  328  may form the shaft portion  310 , the molding material flowing above the magnetic shield  328  may form the first layer  324 , the molding material flowing below the magnetic shield  328  may form the second layer  326 , and the molding material flowing radially outward of the magnetic shield  328  may form the outer wall  340 . In this manner, the first openings  332  may have a diameter or width that are the same as or substantially similar to a diameter or width of the upper rod  423 , and/or the second openings  334  may have a diameter or width that are the same as or substantially similar to a diameter or width of the lower rod  425 . 
     After the molding material is cooled, a bearing holder unit  300  is extracted at operation  440  (shown in  FIG. 7 ). The bearing holder unit  300  includes one or more first features  330  that facilitate restricting rotation of the magnetic shield  328  relative to the first layer  324  and/or second layer  326  (for example, first opening  332 , second opening  334 , protrusion  336 , outer wall  340 , vertex  354 , chord portion  356 ), and one or more second features  330  that facilitate restricting translation of the magnetic shield relative to the first layer  324  and/or second layer  326  (for example, first opening  332 , second opening  334 , protrusion  336 , outer wall  340 , vertex  354 , chord portion  356 ). 
       FIGS. 8-10  show another example integrated magnetic shield and bearing holder or bearing holder unit  500  (for example, bearing holder  260 ). The bearing holder unit  500  includes a shaft portion  510  and a cover portion  520  extending radially outward from the shaft portion  510 . The shaft portion  510  includes a side wall  512  and a ledge  516  extending radially inward from a radially inner surface of the side wall  512 . In this manner, the shaft portion  510  may be used to support an upper bearing  252  through which a shaft  242  is extended. 
     The cover portion  520  has a diameter or width  522  that enables the cover portion  520  to extend across and/or adjacent to the opening defined at the upper end of the side wall  212  of the housing  210 . The cover portion  520  includes a first layer  524  (shown in  FIG. 10 ), a second layer  526  (shown in  FIG. 10 ), and a magnetic shield  528  (shown in  FIGS. 9 and 10 ) between the first layer  524  and second layer  526 . In some examples, the cover portion  520  includes an outer wall  540  extending downward from the first layer  524  and/or second layer  526  such that a space  542  (shown in  FIGS. 9 and 10 ) is defined between the outer wall  540  and the shaft portion  510 . The sizing and shape of the space  542  facilitates optimizing material reduction while restricting movement of the magnetic shield  528 . Additionally, a portion of the outer wall  540  may extend between the first layer  524  and/or second layer  526  to extend circumferentially at least partially about the magnetic shield  528 . Except as otherwise described below, it should be understood that the shaft portion  510  and cover portion  520 , including the magnetic shield  528 , are substantially similar to, and function in substantially the same manner as, the shaft portion  310  and cover portion  320  described above in regard to the bearing holder unit  300 . 
     The first layer  524  and/or second layer  526  have a thickness that enables the cover portion  520  to restrict movement of the magnetic shield  528  while facilitating optimizing material reduction. For example, the first layer  524  may have a thickness that is greater than a thickness of the second layer  526 . In some examples, the thickness of the first layer  524  is greater than a thickness of the first layer  324  of the bearing holder unit  300 . Alternatively, the first layer  524 , second layer  526 , and/or magnetic shield  528  may have any thickness that enables the bearing holder unit  500  function as described herein. 
     The cover portion  520  may include one or more retainers or features  530  that enable the first layer  524 , second layer  526 , and/or magnetic shield  528  to be aligned with each other and restrict relative movement therebetween. In this manner, the features  530  may prevent or restrict rotation of the magnetic shield  528  relative to the first layer  524  and/or second layer  526 . Additionally, the features  530  may prevent or restrict translation of the magnetic shield  528  relative to the first layer  524  and/or second layer  526 . For example, the features  530  may restrict axial movement (for example, movement along the center axis  236 ) and/or lateral movement (for example, movement perpendicular to the center axis  236 ) of the magnetic shield  528  relative to the first layer  524  and/or second layer  526 . 
     As shown in  FIGS. 8-10 , the first layer  524  defines one or more first openings  532  (shown in  FIGS. 8 and 10 ) extending therethrough, the second layer  526  defines a second opening  534  (shown in  FIGS. 9 and 10 ) extending therethrough, and the magnetic shield  528  includes one or more protrusions  536  (shown in  FIGS. 8 and 10 ) extending from a base portion  538  (shown in  FIGS. 9 and 10 ). The protrusions  536  may be sized and/or configured to extend at least partially through the first openings  532 . In this manner, the protrusions  536  may be aligned with the first openings  532  such that the protrusions  536  extend into and/or are seated in the first openings  532 . In some examples, the protrusions  536  do not extend upward beyond an upper surface of the first layer  524  to ensure that the bearing holder unit  500  conforms to an allotted packaging environment. 
     The second layer  526  may include one or more lips  560  (shown in  FIGS. 9 and 10 ) that define the second opening  534 . In some examples, the lips  560  extend circumferentially about the center axis  236 . The lips  560  may include, for example, an inner lip  562  (shown in  FIGS. 9 and 10 ) extending radially outward from and circumferentially along the shaft portion  510  and/or an outer lip  564  (shown in  FIGS. 9 and 10 ) extending radially inward from and circumferentially along the outer wall  540 . In this manner, the magnetic shield  528  may be retained by or held into the bearing holder unit  500 . The lips  560  are configured to couple to the magnetic shield  528  to facilitate supporting the magnetic shield  528 . In some examples, the inner lip  562  and/or outer lip  564  extend radially from and circumferentially along the shaft portion  510  and/or outer wall  540 , respectively, such that the second opening  534  has an annular configuration.  FIG. 11  shows the magnetic shield  528  free from the rest of the bearing holder unit  500 . 
     The bearing holder unit  500  may be produced or manufactured using the system  400  and/or method  402 . To form the lips  560  and define the second opening  534 , the lower rod  425  may have an annular configuration having an inner diameter that is a predetermined amount (for example, two times a length of the inner lip  562 ) greater than an inner diameter of the magnetic shield  528  and/or an outer diameter that is a predetermined amount (for example, two times a length of the outer lip  564 ) less than an outer diameter of the magnetic shield  528 . The bearing holder unit  500  may be formed to include and/or define one or more first features  530  that facilitate restricting rotation of the magnetic shield  528  relative to the first layer  524  and/or second layer  526  (for example, first opening  532 , protrusion  536 ), and one or more second features  530  that facilitate restricting translation of the magnetic shield relative to the first layer  524  and/or second layer  526  (for example, first opening  532 , protrusion  536 , outer wall  540 , lip  560 , inner lip  562 , outer lip  564 ). 
       FIGS. 12 and 13  show yet another example integrated magnetic shield and bearing holder or bearing holder unit  600  (for example, bearing holder  260 ). The bearing holder unit  600  includes a shaft portion  610  and a cover portion  620  extending radially outward from the shaft portion  610 . The shaft portion  610  includes a side wall  612  (shown in  FIG. 13 ) and a ledge  616  extending radially inward from a radially inner surface of the side wall  612 . In this manner, the shaft portion  610  may be used to support an upper bearing  252  through which a shaft  242  is extended. 
     The cover portion  620  has a diameter or width  622  that enables the cover portion  620  to extend across and/or adjacent to the opening defined at the upper end of the side wall  212  of the housing  210 . The cover portion  620  includes a first layer  624  (shown in  FIG. 13 ), a second layer  626 , and a magnetic shield  628  between the first layer  624  and second layer  626 . In some examples, the cover portion  620  includes an outer wall  640  extending downward from the first layer  624  and/or second layer  626  such that a space  642  is defined between the outer wall  640  and the shaft portion  610 . Additionally, a portion of the outer wall  640  may extend between the first layer  624  and/or second layer  626  to extend circumferentially at least partially about the magnetic shield  628 . Except as otherwise described below, it should be understood that the shaft portion  610  and cover portion  620 , including the magnetic shield  628 , are substantially similar to, and function in substantially the same manner as, the shaft portion  310  and cover portion  320  described above in regard to the bearing holder unit  300  and/or the shaft portion  510  and cover portion  520  described above in regard to the bearing holder unit  500 . 
     The first layer  624  may have a thickness that is greater than a thickness of the second layer  626 . In some examples, the thickness of the first layer  624  is greater than a thickness of the first layer  324  of the bearing holder unit  300  and/or of the first layer  524  of the bearing holder unit  500 . Alternatively, the first layer  624 , second layer  626 , and/or magnetic shield  628  may have any thickness that enables the bearing holder unit  600  function as described herein. 
     The cover portion  620  may include one of more retainers or features  630  (shown in  FIG. 12 ) that enable the first layer  624 , second layer  626 , and/or magnetic shield  628  to be aligned with each other and restrict relative movement therebetween. In this manner, the features  630  may prevent or restrict rotation of the magnetic shield  628  relative to the first layer  624  and/or second layer  626 . Additionally, the features  630  may prevent or restrict translation of the magnetic shield  628  relative to the first layer  624  and/or second layer  626 . For example, the features  630  may restrict axial movement (for example, movement along the center axis  236 ) and/or lateral movement (for example, movement perpendicular to the center axis  236 ) of the magnetic shield  628  relative to the first layer  624  and/or second layer  626 . 
     As shown in  FIG. 12 , the first layer  624 , second layer  626 , and/or magnetic shield  628  may include a plurality of vertices  654  at a radially outer surface of the first layer  624 , second layer  626 , and/or magnetic shield  628  between which at least one chord portion  656  extends. The vertices  654  and/or chord portion  656  may engage a radially inner surface of the outer wall  640  such that rotation and/or translation of the magnetic shield  628  relative to the first layer  624  and/or second layer  626  is prevented or restricted. In some examples, the radially outer surfaces of the first layer  624 , second layer  626 , and/or magnetic shield  628  include a plurality of opposite chord portions  656 , each between an adjacent pair of curved portions  658 . Alternatively, the first layer  624 , second layer  626 , and/or magnetic shield  628  may have any configuration that enables the bearing holder unit  600  to function as described herein. 
     The second layer  626  may include one or more lips  660  extending circumferentially about the center axis  236 . The lips  660  may include, for example, an inner lip  662  extending radially outward from and circumferentially along the shaft portion  610  and/or an outer lip  664  extending radially inward from and circumferentially along the outer wall  640 . In this manner, the magnetic shield  628  may be retained by or held into the bearing holder unit  600 . 
     In some examples, the second layer  626  includes one or more ribs  670  (shown in  FIG. 12 ) spaced circumferentially about the center axis  236  and extending radially between the shaft portion  610  and the outer wall  640 . The ribs  670  may be connected to and extend longitudinally between, for example, the inner lip  662  and the outer lip  664 . The lips  660  and/or ribs  670  are configured to support the magnetic shield  628  and define a plurality of second openings  634  (shown in  FIG. 12 ). In some examples, the inner lip  662  and/or outer lip  664  extend radially from and circumferentially along the shaft portion  610  and/or outer wall  640 , respectively, between an adjacent pair of ribs  670 , such that the second opening  634  defined between the adjacent pair of ribs  670  has an annulus sectoral configuration. The ribs  670  may provide additional support to the magnetic shield  628  (for example, relative to a magnetic shield not supported by ribs) to reduce a likelihood of shape distortion during manufacture of the bearing holder unit  600 .  FIG. 14  shows the magnetic shield  628  free from the rest of the bearing holder unit  600 . 
     The bearing holder unit  600  may be produced or manufactured using the system  400  and/or method  402 . To form the lips  660  and define circumferential edges of the second openings  634 , the lower rod  425  may have an annular configuration having an inner diameter that is a predetermined amount (for example, two times a length of the inner lip  662 ) greater than an inner diameter of the magnetic shield  628  (for example, width  348 ) and/or an outer diameter that is a predetermined amount (for example, two times a length of the outer lip  664 ) less than an outer diameter of the magnetic shield  628  (for example, width  352 ). To form the ribs  670  and define generally or substantially radial edges of the second openings  634 , an upper surface of the lower rod  425  include one or more circumferentially-spaced, radially-extending channels defined therein. The bearing holder unit  600  may be formed to include and/or define one or more first features  630  that facilitate restricting rotation of the magnetic shield  628  relative to the first layer  624  and/or second layer  626  (for example, vertex  654 , chord portion  656 , lip  660 , inner lip  662 , outer lip  664 ), and one or more second features  630  that facilitate restricting translation of the magnetic shield relative to the first layer  624  and/or second layer  626  (for example, vertex  654 , chord portion  656 , lip  660 , inner lip  662 , outer lip  664 ). 
     Examples are described herein and illustrated in the accompanying drawings to disclose aspects of the disclosure and also to enable a person skilled in the art to practice the aspects, including making or using the above-described systems and executing or performing the above-described methods. Having described aspects of the disclosure in terms of various examples with their associated operations, it will be apparent that modifications and variations are possible without departing from the scope of the disclosure as defined in the appended claims. That is, aspects of the disclosure are not limited to the specific examples described herein, and all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. 
     Components of the systems and/or operations of the methods described herein may be utilized independently and separately from other components and/or operations described herein. Moreover, the methods described herein may include additional or fewer operations than those disclosed, and the order of execution or performance of the operations described herein is not essential unless otherwise specified. That is, the operations may be executed or performed in any order, unless otherwise specified, and it is contemplated that executing or performing a particular operation before, contemporaneously with, or after another operation is within the scope of the disclosure. Although specific features of various examples of the disclosure may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the disclosure, any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing. 
     When introducing elements of the disclosure or the examples thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. References to an “embodiment” or an “example” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments or examples that also incorporate the recited features. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be elements other than the listed elements. The phrase “one or more of the following: A, B, and C” means “at least one of A and/or at least one of B and/or at least one of C.” 
     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 have 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 language of the claims.