Patent Publication Number: US-2017363206-A1

Title: Gear drive assembly having one of a first selected gear and a second selected gear and a method of producing the same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. patent application Ser. No. 62/352,697 filed on Jun. 21, 2016, the disclosure of which is herein incorporated by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     A gear drive assembly for an actuator and a method of manufacturing the gear drive assembly. 
     2. Description of Related Art 
     Many fluid flow devices in vehicles, such as a turbochargers and exhaust gas recirculation (EGR) valves, use an actuator system to control their functions and performance. For example, in certain actuator systems, pneumatic and electric actuators are used to provide positional control of variable vanes of a turbocharger or a valve plate of an EGR valve to adjust and maintain fluid pressure and fluid flow within an intake manifold of an engine. Controlling the fluid pressure and the fluid flow within the intake manifold provides optimum performance while maintaining legislated vehicle emissions. 
     Traditionally, the actuator includes a gear drive assembly which transmits rotational motion to the fluid flow device. The gear drive assembly provides a plurality of gears which collectively interact to provide a velocity and a torque to the fluid flow device for moving the fluid flow device. The velocity and the torque needed to move the fluid flow device varies with different vehicle applications. As such, numerous gear drive assemblies must be produced, each having unique gear arrangements and unique housings to retain the gear arrangements, which requires additional tooling and manufacturing lines to produce. As such, there remains a need to provide an improved gear drive assembly. 
     SUMMARY OF THE INVENTION AND ADVANTAGES 
     The subject invention provides for a gear drive assembly for use with and driven by a motor in an actuator, with the actuator capable of moving an output shaft between a plurality of positions. The actuator has one of a first output, having a first velocity and a first torque, and a second output, having a second velocity and a second torque. The gear drive assembly comprises a housing having an internal surface defining a cavity and a gear arrangement disposed in the cavity and comprising a drive gear, at least one driven gear, and one of a first selected gear and a second selected gear engageable with both of the drive and the at least one driven gears to transmit rotation from the drive gear to the at least one driven gear. The drive and the at least one driven gears are each rotatably coupled with the housing. 
     The drive and the at least one driven gears and the first selected gear have a first gear ratio for selectively moving the output shaft with the first output. The drive and the at least one driven gears and the second selected gear have a second gear ratio not equal to the first gear ratio for selectively moving the output shaft with the second output. The internal surface of the housing defines a first gear retention feature to facilitate selective rotatable coupling of the first selected gear with the housing, and a second gear retention feature to facilitate selective rotatable coupling of the second selected gear with the housing. 
     The subject invention further provides for a method of manufacturing a gear drive assembly for use with and driven by a motor in an actuator. The actuator is capable of moving an output shaft between a plurality of positions, with the actuator having one of a first output, having a first velocity and a first torque, and a second output, having a second velocity and a second torque. The gear drive assembly comprises a housing having an internal surface defining a cavity, and a gear arrangement disposed in the cavity and comprising a drive gear, at least one driven gear, and one of a first selected gear and a second selected gear. The drive and the at least one driven gears and the first selected gear have a first gear ratio for selectively moving the output shaft with the first output, and the drive and the at least one driven gears and the second selected gear have a second gear ratio not equal to the first gear ratio for selectively moving the output shaft with the second output. 
     The method comprises the steps of rotatably coupling the drive and the at least one driven gears with the housing within the cavity, selecting one of the first and second selected gears, engaging the one of the first and second selected gears with both of the drive and the at least one driven gears, and rotatably coupling the one of the first and second selected gears with the housing within the cavity. 
     Accordingly, the gear drive assembly allows for different properties (i.e., the first and second outputs) by selecting between the first and second selected gears. The housing is correspondingly designed to accommodate each of the first and second selected gears. As such, only one housing is needed to accommodate two different outputs. Because one housing is needed rather than two, manufacturing costs are reduced. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Advantages of the subject invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings. 
         FIG. 1  is a schematic view of an actuator system used with an engine, an intake manifold, an exhaust manifold, and a turbocharger. 
         FIG. 2  is a side elevational view of an actuator of the actuator system, showing a motor and a gear drive assembly. 
         FIG. 3  is a perspective view of a valve for use with the actuator system. 
         FIG. 4  is a top elevational view of the actuator of the actuator system. 
         FIG. 5  is a cross-sectional view of the actuator taken along Section A-A shown in  FIG. 4 . 
         FIG. 6  is a bottom elevational view of the actuator, with a second section of a housing of the gear drive assembly removed and showing a first selected gear. 
         FIG. 7  is a bottom elevational view of the actuator, with the second section assembly removed and showing a second selected gear. 
         FIG. 8  is a bottom elevational view of the motor, a first section of the housing, at least one driven gear, and a second driven gear. 
         FIG. 9  is a top elevational view of the first section of the housing, a drive gear, at least one driven gear, and a second driven gear. 
         FIG. 10  is a perspective view of a gear drive assembly having a housing which has a first section, a second section, and a third section. 
         FIG. 11  is a bottom elevational view of the gear drive assembly shown in  FIG. 10 , with the second and third sections of the housing of the gear drive assembly removed and showing a first selected gear and a first selected first driven gear. 
         FIG. 12  is a bottom elevational view of the gear drive assembly shown in  FIG. 10 , with the second and third sections of the housing of the gear drive assembly removed and showing a second selected gear and a second selected first driven gear. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the Figures, wherein like numerals indicates like or corresponding parts throughout the several views, an actuator system  20  is generally shown in  FIG. 1 . The actuator system  20  is typically used for controlling a control shaft  21  within a vehicle. In one example, the control shaft  21  controls the flow of a fluid to or from an engine  22  of the vehicle. As shown schematically in  FIG. 1 , the vehicle may comprise the engine  22 , an intake manifold  24  configured to flow air into the engine  22 , and an exhaust manifold  26  configured to flow exhaust out of the engine  22 . In one embodiment, the control shaft  21  is used in a turbocharger  28  which is fluidly coupled with each of the intake manifold  24  and the exhaust manifold  26  to increase flow of the air into the engine  22  by way of utilizing the energy of the moving exhaust flowing out of the engine  22 , as is commonly known to those having ordinary skill in the art. The actuator system  20  is positioned between the exhaust manifold  26  and the turbocharger  28 , with the actuator system  20  controlling a position of the turbocharger  28  (described in greater detail below) through the control shaft  21 , which in-turn controls the pressure and the flow of the air into the engine  22  through the intake manifold  24  and is commonly referred to as boost pressure. 
     The vehicle may further comprise an electronic control unit (ECU)  30  and an actuator controller  32 . The ECU  30  may be connected to the actuator controller  32  by a wire harness  34  having multiple conductors and connectors. The actuator controller  32  may also be connected to the actuator system  20  by a wire harness  36  having multiple conductors and connectors. For this illustration, the actuator controller  32  is shown as separate component. However, one having skill in the art will appreciate that the actuator controller  32  may be integrated within actuator system  20  or the ECU  30 . 
     The ECU  30  may provide an electrical position input signal to the actuator controller  32  that may indicate a desired position of the control shaft  21  as controlled by the actuator system  20 , as will be further understood through further description below. The actuator controller  32  may provide the necessary electrical control signal to the actuator system  20  to achieve the desired position of the control shaft  21 . 
     The actuator system  20  may also provide feedback in the form of an electrical position output signal to the actuator controller  32 . A “closed loop” control scheme may be used to maintain a desired position of the control shaft  21  as controlled by the actuator system  20  by comparing the feedback electrical position output signal value to a desired value and may adjust the electrical control signal to the actuator system  20  to maintain the resulting position of the control shaft  21  and the resultant fluid flow and boost pressure. 
     Although the actuator system  20  is shown in  FIG. 1  controlling a position of the turbocharger  28 , one having skill in the art will appreciate that the actuator system  20  may be used anywhere within automobiles for controlling the flow of a fluid to or from an engine, such as with an exhaust gas recirculation (EGR) valve or as a throttle fluidly coupled to an intake manifold  24 . 
     The actuator system  20  comprises an output shaft  88 , movable between a plurality of positions. The output shaft  88  may be coupled to the control shaft  21  of the turbocharger  28 , as described above. The turbocharger  28  may comprise a turbine fluidly coupled with the exhaust manifold  26  and a compressor fluidly coupled with the intake manifold  24 . The turbine may have a plurality of vanes. The movement of the control shaft  21  by the movement of the output shaft  88  may vary the orientation of the vanes to alter the flow of the fluid past the turbine, which in-turn alters the pressure and the flow of the fluid from the compressor into the intake manifold  24 . 
     In another embodiment, the control shaft  21  may be used in a valve  38 . The output shaft  88  may be coupled to the control shaft  21  of the valve  38 , as shown in  FIG. 3 . Movement of the output shaft  88  between the plurality of positions may move the control shaft  21  of the valve  38  between a plurality of positions. The valve  38  may be further defined as a butterfly valve  40 . The butterfly valve  40  may comprise a plate  42  coupled to the control shaft  21  and pivotally disposed within a valve housing  44  defining a bore  46 , with the plate  42  capable of changing the cross-sectional area of the bore  46  between the plurality of positions to alter the flow of the fluid. One having skill in the art will appreciate that the valve  38  may be any particular valve capable of controlling the flow of a fluid, such as a poppet valve, a flap valve, or a ball valve. 
     The plurality of positions of the control shaft  21  of the valve  38  may comprise a fully open position and a fully closed position. When the control shaft  21  of the valve  38  is in the fully open position, the valve  38  induces the least amount of restriction to the flow of the fluid. When the control shaft  21  of the valve  38  is in the fully closed position, the valve  38  induces the greatest amount of restriction to the flow of the fluid. The greatest amount of restriction to the flow of the fluid may result in complete stop of fluid flow. The plurality of positions may comprise at least one intermediate position between the fully open position and the fully closed position capable of partially restricting the flow of the fluid. One having skill in the art will appreciate that the plurality of positions of the control shaft  21  of the valve  38  may be any number of positions and any type of position to create a desire fluid flow. One having skill in the art will appreciate that the actuator system  20  may be configured to actuate any suitable component through the rotation of the output shaft  88 . 
     The actuator system  20  further comprises an actuator  48 , which is shown in  FIGS. 2 and 4 . The actuator  48  is capable of moving the output shaft  88  between the plurality of positions and having one of a first output, having a first velocity and a first torque, and a second output, having a second velocity and a second torque. Said differently, depending on the configuration of the actuator  48  (as will be further described below) the actuator  48  may have one of the first and second outputs. The first and second outputs have differing specific properties (i.e., the first velocity, the first torque, the second velocity, and the second torque), with the specific properties having desired use in various applications. For example, the first velocity may be greater than the second velocity while the second torque may be greater than the first torque. Said differently, the first output may be capable of moving the output shaft  88  with high velocity but low torque while the second output may be capable of moving the output shaft  88  with low velocity but high torque. As such, the actuator  48  may be configured to meet desired velocity and torque characteristics of the output shaft  88 . It is to be appreciated that the opposite may be true (i.e., the first velocity may be less than the second velocity while the second torque may be less than the first torque). 
     The actuator  48  as described herein is capable of having the first and second outputs. It is to be appreciated that the actuator  48  may be configured to have any number of suitable outputs. 
     Furthermore, the actuator  48  may produce rotary or linear motion. For illustrative purposes, the actuator  48  shown in the Figures produces rotary motion. The actuator  48  comprises a motor  50 . The motor  50  may be a direct current (D.C.) motor. The D.C. motor may or may not include brushes to produce motion. The motor  50  may be configured to be controlled by an electrical control signal. More specifically, at least one of the ECU  30  and the actuator controller  32  control the motor  50  (and, moreover, the actuator  48 ) by the electrical control signal. One having skill in the art will appreciate that the motor  50  and the actuator  48  may be controlled by any suitable means, such as a mechanical switch. 
     As shown in  FIG. 5 , the actuator  48  further comprises a gear drive assembly  52  driven by the motor  50 . The gear drive assembly  52  comprises a housing  54  having an internal surface  56  defining a cavity  58  and a gear arrangement  60  disposed in the cavity  58  and comprising a drive gear  62 , at least one driven gear  89 , and one of a first selected gear  66  and a second selected gear  68  engageable with both of the drive and the at least one driven gears  62 ,  89  to transmit rotation from the drive gear  62  to the at least one driven gear  89 . The drive and the at least one driven gears  62 ,  89  are each rotatably coupled with the housing  54 . The drive and the at least one driven gears  62 ,  89  and the first selected gear  66  have a first gear ratio to selectively move the output shaft  88  with the first output, and the drive and the at least one driven gears  62 ,  89  and the second selected gear  68  have a second gear ratio not equal to the first gear ratio to selectively move the output shaft  88  with the second output. The internal surface  56  of the housing  54  defines a first gear retention feature  70  to facilitate selective rotatable coupling of the first selected gear  66  with the housing  54  and a second gear retention feature  72  to facilitate selective rotatable coupling of the second selected gear  68  with the housing  54 . 
     The first and second gear ratios are described below in terms of respective diameters of the gears. One having skill in the art will appreciate that gear ratios may be determined by the respective diameters of the gears or by a number of gear teeth of each gear. As such, although the number of gear teeth of each gear are not explicitly discussed below, it should be appreciated that the first and second gear ratios may be determined based on the number of teeth of each gear. 
     As shown in  FIGS. 6 and 7 , the drive gear  62  may be rotatable about a first axis A 1 , the first and second selected gears  66 ,  68  may be rotatable about second and third axes A 2 , A 3 , respectively, and the at least one driven gear  89  may be rotatable about a fourth axis A 4 . Each of the first, second, third, and fourth axes A 1 , A 2 , A 3 , A 4  may be substantially parallel. One having skill in the art will appreciate that the axes A 1 , A 2 , A 3 , A 4  may be transverse to one another. 
     As shown in  FIG. 5 , the motor  50  may have a shaft  74  rotatable about a shaft axis S and capable of transmitting rotational force with the shaft  74 . The shaft  74  may extend through the housing  54  and may be at least partially disposed in the cavity  58 , with the drive gear  62  operably coupled with the shaft  74 . Moreover, the housing  54  may comprised of at least a first section  76  and a second section  78  each having the internal surface  56  defining the cavity  58 , with the shaft  74  of the motor  50  extending through one of the first and second sections  76 ,  78  and is at least partially disposed in the cavity  58 . The first and second sections  76 ,  78  may abut one another and may be sealed at the abutment to prevent debris from entering the cavity  58  therethrough. In the embodiment shown in the Figures, the shaft  74  extends through the first section  76  of the housing  54 . One having skill in the art will appreciate that the shaft  74  may extend through the second section  78  of the housing  54 . 
     Alternatively, the housing  54  may comprise a third section  79  in addition to the first and second sections  76 ,  78  as shown in  FIG. 10 . The first, second, and third sections  76 ,  78 ,  79  each have the internal surface  56  defining the cavity  58 , with the shaft  74  of the motor  50  extending through one of the first, second, and third sections  76 ,  78 ,  79  and with the shaft  74  at least partially disposed in the cavity  58 . The first and second sections  76 ,  78  may abut one another and the second and third sections  78 ,  79  may abut one another. The first, second, and third sections  76 ,  78 ,  79  may be sealed at the respective abutments to prevent debris from entering the cavity  58  therethrough. One having skill in the art will appreciate that the housing  54  may be comprised of any number of sections abutting one another in any suitable order and arranged in any suitable configuration. 
     The drive gear  62  may be operably coupled with the shaft  74  of the motor  50 . Furthermore, the drive gear  62  may be fixed to and rotatable with the shaft  74  about the shaft axis S. In one embodiment, the first axis A 1  is aligned coaxial with the shaft axis S. As such, the drive gear  62  is fixed to the shaft  74  such that motion of the shaft  74  is imparted directly to the drive gear  62 . One having skill in the art will appreciate that the drive gear  62  may be coupled to the shaft  74  in any suitable way. 
     As shown in  FIGS. 6 and 7 , the drive gear  62  may have gear teeth  80  extending radially and defining an input diameter ID of the drive gear  62 . As shown in the Figures, the drive gear  62  may have a substantially circular configuration. As such, the drive gear  62  may be referred to as a spur gear. Furthermore, the drive gear  62  may be comparatively smaller than the at least one driven gear  89  and the first and second selected gears  66 ,  68 . As such, the drive gear  62  may be referred to as a pinion gear. One having skill in the art will appreciate that the drive gear  62  may have any suitable gear configuration, such as a bevel gear configuration. 
     As shown in  FIGS. 6 and 7 , the at least one driven gear  89  may have gear teeth  82  extending radially and defining an output diameter OD of the at least one driven gear  89 . As shown in the Figures, the at least one driven gear  89  may have a substantially circular configuration. As such, the at least one driven gear  89  may be referred to as a spur gear. Furthermore, the at least one driven gear  89  may have a first gear section  84  and a second gear section  86  spaced from and fixed to the first gear section  84 . Both of the first and second gear sections  84 ,  86  may have a substantially circular configuration. As such, the at least one driven gear  89  may be referred to as two spur gears. In addition, the first and second gear sections  84 ,  86  may be fixed to one another such that the first and second gear sections  84 ,  86  rotate in unison about the fourth axis A 4 . As such, the at least one driven gear  89  may be referred to as a compound gear. One having skill in the art will appreciate that the at least one driven gear  89  may have any suitable gear configuration, such as a bevel gear configuration. 
     The at least one driven gear  89  may be rotatable about the fourth axis A 4  and may be operably coupled with the output shaft  88 . The output shaft  88  may extend through the housing  54  from the cavity  58  along an output axis O. More specifically, the output shaft  88  may extend through the second section  78  of the housing  54 . The output shaft  88  may be supported by the second section  78  of the housing  54  by a bearing and a bushing, which allows the output shaft  88  to rotate about the output axis O. The rotation of the at least one driven gear  89  may rotate the output shaft  88  between the plurality of positions. In one embodiment, the at least one driven gear  89  may be fixed to the output shaft  88  in what is commonly referred to in the art as a two-stage gear drive. 
     Alternatively, the at least one driven gear  89  of the gear arrangement  60  may be further defined as a first driven gear  89  and a second driven gear  90  engageable with the first driven gear  89 , as shown in  FIGS. 6 and 7 . In such an embodiment, the description of the at least one driven gear  89  above is applicable to the first driven gear  89 . As such, the first driven gear  89  may be rotatable about the fourth axis A 4 , the first and second gear sections  84 ,  86 , and the gear teeth  82  extending radially and defining the output diameter OD, as described above. 
     The first gear section  84  of the first driven gear  89  may be engageable with the one of the first and second selected gears  66 ,  68  and the second gear section  86  of the first driven gear  89  may be engageable with the second driven gear  90 . The second driven gear  90  may have gear teeth  92  extending radially. The second driven gear  90  may be rotatably coupled with the housing  54  along a fifth axis A 5 . As shown in  FIG. 5 , the fifth axis A 5  may be substantially parallel to the first, second, third, and fourth axes A 1 , A 2 , A 3 , A 4 . As shown in the Figures, the second driven gear  90  may have a partially circular configuration. As such, the second driven gear  90  may be referred to as a partial spur gear. Furthermore, the second driven gear  90  may be referred to as a sector gear. One having skill in the art will appreciate that the second driven gear  90  may have any suitable gear configuration, such as a complete spur gear or a bevel gear configuration. 
     As shown in  FIG. 5 , the second driven gear  90  may be fixed to the output shaft  88  in what is commonly referred to in the art as a three-stage gear drive. The fifth axis A 5  of the second driven gear  90  may be coaxial with the output axis O of the output shaft  88 . The drive gear  62  may be indirectly coupled to the output shaft  88  through the second driven gear  90 . 
     As shown in  FIGS. 6 and 7 , each of the one of the first and second selected gears  66 ,  68  may have a first gear section  94 ,  98  and a second gear section  96 ,  100  spaced from and fixed to the first gear section  94 ,  98 , with the first gear section  94 ,  98  of each of the first and second selected gears  66 ,  68  being engageable with the drive gear  62  and the second gear section  96 ,  100  of each of the first and second selected gears  66 ,  68  being engageable with the at least one driven gear  89 . More specifically, the second gear section  96 ,  100  of each of the first and second selected gears  66 ,  68  may be engageable with the first driven gear  89 . The first gear section  94 ,  98  of each of the first and second selected gears  66 ,  68  may have gear teeth  102 ,  104  extending radially and defining a first diameter D 1  of the first selected gear  66  (shown in  FIG. 6 ) and a second diameter D 2  (shown in  FIG. 7 ) of the second selected gear  68 . The second gear section  96 ,  100  of each of the first and second selected gears  66 ,  68  may have gear teeth  106 ,  108  extending radially and defining a third diameter D 3  (shown in  FIG. 6 ) of the first selected gear  66  and a fourth diameter D 4  (shown in  FIG. 7 ) of the second selected gear  68 . Both of the first and second gear sections  94 ,  96 ,  98 ,  100  of each of the first and second selected gears  66 ,  68  may have a substantially circular configuration. As such, each of the first and second selected gears  66 ,  68  may be referred to as two spur gears. In addition, the first and second gear sections  94 ,  96 ,  98 ,  100  may be fixed to one another such that the first and second gear sections  94 ,  96 ,  98 ,  100  rotate in unison about the second and third axes A 2 , A 3 , respectively. As such, each of the first and second selected gears  66 ,  68  may be referred to as a compound gear. One having skill in the art will appreciate that the first and second selected gears  66 ,  68  may have any suitable gear configuration, such as a bevel gear configuration. 
     As shown in  FIGS. 6 and 7 , the gear teeth  102 ,  104  of the first gear section  94 ,  98  of the first and second selected gears  66 ,  68  may be engageable with the gear teeth  80  of the drive gear  62  to define a first gear stage  110 . The first gear section  94 ,  98  of the first and second selected gears  66 ,  68  and the drive gear  62  may be positioned on a first plane, shown in  FIG. 5 . The gear teeth  106 ,  108  of the second gear section  96 ,  100  of the first and second selected gears  66 ,  68  may be engageable with the gear teeth  82  of the at least one driven gear  89  to define a second gear stage  112 . More specifically, the gear teeth  106 ,  108  of the second gear section  96 ,  100  of the first and second selected gears  66 ,  68  may be engageable with the gear teeth  82  of the first driven gear  89  to define the second gear stage  112 . The second gear section  96 ,  100  of the first and second selected gears  66 ,  68  and the at least one driven gear  89  (i.e., the first driven gear  89 ) may be positioned on a second plane. As shown in  FIG. 5 , the first and second planes are spaced from and substantially parallel to one another. It is to be appreciated that the first and second planes may be substantially the same plane or transverse to one another. If the gear arrangement  60  has the second driven gear  90 , the gear teeth  82  of the second gear section  86  of the first driven gear  89  may be engageable with the gear teeth  92  of the second driven gear  90  to define a third gear stage  114 . 
     As shown in  FIGS. 6, 7, 8, and 9 , the first and second diameters D 1 , D 2  of the first gear sections  94 ,  98  of the first and second selected gears  66 ,  68 , respectively, may correspond with the first and second gear retention features  70 ,  72  of the housing  54 , respectively, to facilitate engagement of the first gear section  94 ,  98  of the one of the first and second selected gears  66 ,  68  with the drive gear  62  having the input diameter ID. Likewise, the third and fourth diameters D 3 , D 4  of the second gear sections  96 ,  100  of the first and second selected gears  66 ,  68 , respectively, may correspond with the first and second gear retention features  70 ,  72  of the housing  54 , respectively, to facilitate engagement of the second gear section  96 ,  100  of the one of the first and second selected gears  66 ,  68  with the at least one driven gear  89  having the output diameter OD (i.e., the first driven gear  89  when the second driven gear  90  is present). Said differently, the housing  54  is configured to position each of the first selected gear  66 , having the first and third diameters D 1 , D 3 , and the second selected gear  68 , having the second and fourth diameters D 2 , D 4 , into engagement with each of the drive and the at least one driven gears  62 ,  89 . The configuration of the housing  54  to position each of the first and second selected gears  66 ,  68  will be described in greater detail below. 
     As described above, the drive and the at least one driven gears  62 ,  89  and the first selected gear  66  have the first gear ratio to selectively move the output shaft  88  with the first output, and the drive and the at least one driven gears  62 ,  89  and the second selected gear  68  have the second gear ratio not equal to the first gear ratio to selectively move the output shaft  88  with the second output. The first and second selected gears  66 ,  68  are selectively placed into engagement with the drive and the at least one driven gears  62 ,  89 . As such, the diameters of the first and second selected gears  66 ,  68  facilitate the difference in the first and second gear ratios (and the first and second outputs). For example, as shown in the Figures, the third and fourth diameters D 3 , D 4  of the second gear sections  96 ,  100  of the first and second selected gears  66 ,  68 , respectively, are substantially equal. However, the first and second diameters D 1 , D 2  of the first gear sections  94 ,  98  of the first and second selected gears  66 ,  68 , respectively, are different. Specifically, the first diameter D 1  of the first gear section  94  of the first selected gear  66  is greater than the second diameter D 2  of the first gear section  98  of the second selected gear  68 . As such, the first velocity of the first output is less than the second velocity of the second output and the first torque of the first output is greater than the second torque of the second output. Said differently, the first selected gear  66  may provide greater mechanical advantage than the second selected gear  68 , while the second selected gear  68  may provide faster response than the first selected gear  66 . It is to be appreciated that the opposite may true (i.e., the first velocity may be greater than the second velocity and the first torque may be less than the second torque). 
     Although the gear arrangement  60  as described herein comprises the first and second selected gears  66 ,  68  with one of the two being selected and positioned into the cavity  58  to the engage the drive and the at least one driven gears  62 ,  89 , one having skill in the art will appreciate that more than two selected gears may be used in accordance with the invention. Moreover, one having skill in the art will appreciate that more than one selected gears may be used at any given time, as will be described in greater detail below. Furthermore, more than one selected gear may engage the drive and the at least one driven gears  62 ,  89  without escaping the scope of the present invention. Also, the total number of gears in the gear arrangement  60  are demonstrative in nature. It is to be appreciated that the gear arrangement  60  may comprise any total number of gears. 
     The operation of transmitting rotation from the motor  50  to the output shaft  88  in accordance with the embodiment shown in the Figures is described below for illustrative purposes. One having skill in the art will appreciate that, although not expressly recited herein, numerous operations are possible in accordance with the present invention. 
     When the motor  50  is activated, the motor  50  rotates the shaft  74  about the shaft axis S. The shaft  74  is coupled to the drive gear  62 , which causes the drive gear  62  to rotate about the first axis A 1 . The drive gear  62  engages the first gear section  94 ,  98  of first selected gear  66  or the second selected gear  68  (whichever is disposed in the housing  54 ) at the first stage, which causes the first selected gear  66  or the second selected gear  68  to rotate about the second axis A 2  or the third axis A 3 , respectively. The first gear section  94 ,  98  and the second gear section  96 ,  100  of each of the first and second selected gears  66 ,  68  are fixed to one another. As such, rotation of the first gear section  94 ,  98  results in simultaneous rotation of the second gear section  96 ,  100 . 
     The second gear section  96 ,  100  of the first selected gear  66  or the second selected gear  68  (whichever is disposed in the housing  54 ) engages the first gear section  84  of the first driven gear  89  at the second stage, which causes the first driven gear  89  to rotate about the fourth axis A 4 . The first gear section  84  and the second gear section  86  of the first driven gear  89  are fixed to one another. As such, rotation of the first gear section  84  results in simultaneous rotation of the second gear section  86 . The second gear section  86  of the first driven gear  89  engages the second driven gear  90  at the third stage, which causes the second driven gear  90  to rotate about the fifth axis A 5 . The second driven gear  90  is coupled to the output shaft  88 , which causes the output shaft  88  to rotate about the output axis O between the plurality of positions. 
     Each of the first and second selected gears  66 ,  68  may define a hole  116  extending therethrough (as shown in  FIGS. 6 and 7 ), with the hole  116  of the first and second selected gears  66 ,  68  corresponding with the first and second gear retention features  70 ,  72  (as shown in  FIGS. 8 and 9 ), respectively, to facilitate selective rotatable coupling of the one of the first and second selected gears  66 ,  68  with the housing  54 . The holes  116  of the first and second selected gears  66 ,  68  are defined along the second and third axes A 2 , A 3 . One having skill in the art will appreciate that the hole  116  may be defined anywhere within the first and second selected gears  66 ,  68 . 
     As shown in  FIGS. 8 and 9 , the internal surface  56  of the housing  54  may define a pair of first gear pockets  118  as the first gear retention feature  70 , and the internal surface  56  of the housing  54  may define a pair of second gear pockets  120  as the second gear retention feature  72 . More specifically, the internal surfaces  56  of the at least the first and second sections  76 ,  78  of the housing  54  may each individually define the first gear pocket  118  which collectively define the first gear retention feature  70 . The internal surfaces  56  of the at least the first and second sections  76 ,  78  of the housing  54  may each define the second gear pocket  120  which collectively define the second gear retention feature  72 . 
     As shown in  FIG. 5 , the gear drive assembly  52  may further comprise a pin  122  extending between a first end  124  and a second end  126  through the hole  116  of the one of the first and second selected gears  66 ,  68 . The first and second ends  124 ,  126  of the pin  122  may be individually disposed within one of the pair of first gear pockets  118  and the pair of second gear pockets  120  of the housing  54  to facilitate selective rotatable coupling of the one of the first and second selected gears  66 ,  68  with the housing  54 . More specifically, each of the pair of first gear pockets  118  may have a cylindrical configuration, with the pair of first gear pockets  118  opening toward one another to receive the pin  122  and operably couple the pin  122  to the housing  54 . Likewise, each of the pair of second gear pockets  120  may have a cylindrical configuration, with the pair of second gear pockets  120  opening toward one another to receive the pin  122  and operably couple the pin  122  to the housing  54 . The pin  122  may have a cylindrical configuration corresponding to the cylindrical configurations of the first and second gear pockets  118 ,  120 . The cylindrical configuration of the first and second gear pockets  118 ,  120  accept the pin  122  and retain the pin  122  laterally to the second and third axes A 2 , A 3 , respectively. 
     The pin  122  may be disposed within each of the first gear pockets  118  when the first selected gear  66  is disposed in the cavity  58 , with the first gear section  94  having the first diameter D 1  engaged with the drive gear  62  having the input diameter ID to define the first gear stage  110 , and with the second gear section  96  having the third diameter D 3  engaged with the at least one driven gear  89  having the output diameter OD to define the second gear stage  112  for selectively moving the output shaft  88  with the first output. More specifically, the second gear section  96  having the third diameter D 3  may be engaged with the first driven gear  89  having the output diameter OD to define the second gear stage  112  for selectively moving the output shaft  88  with the first output. Likewise, the pin  122  may be disposed within each of the second gear pockets  120  when the second selected gear  68  is disposed in the cavity  58 , with the first gear section  98  having the second diameter D 2  engaged with the drive gear  62  having the input diameter ID to define the first gear stage  110 , and with the second gear section  100  having the fourth diameter D 4  engaged with the at least one driven gear  89  having the output diameter OD to define the second gear stage  112  for selectively moving the output shaft  88  with the second output. More specifically, the second gear section  100  having the fourth diameter D 4  may be engaged with the first driven gear  89  having the output diameter OD to define the second gear stage  112  for selectively moving the output shaft  88  with the second output. Therefore, the pair of second gear pockets  120  may be empty when the first and second ends  124 ,  126  of the pin  122  are individually disposed within the pair of first gear pockets  118  and the pair of first gear pockets  118  may be empty when the first and second ends  124 ,  126  of the pin  122  are individually disposed within the pair of second gear pockets  120 . 
     As shown in  FIGS. 6-9 , the internal surface  56  may segregate the cavity  58  into at least a common chamber  128  having a configuration corresponding with the drive and the at least one driven gears  62 ,  89 , a first chamber  130  having a configuration corresponding with the first selected gear  66 , and a second chamber  132  having a configuration corresponding with the second selected gear  68 . The first and second chambers  130 ,  132  may open into the common chamber  128 , with the configurations of the common chamber  128  and the first and second chambers  130 ,  132  defining a gap  134  between the drive, the at least one driven, first selected, and second selected gears  62 ,  89 ,  66 ,  68  and the housing  54 . 
     The gap  134  between the drive and the at least one driven gears  62 ,  89  and the first and second selected gears  66 ,  68  and the housing  54  is nominal to facilitate rotation of the first and second selected gears  66 ,  68 . Said differently, the common, first, and second chambers  128 ,  130 ,  132  have a shape and a configuration similar to the drive and the at least one driven gears  62 ,  89  and the first and second selected gears  66 ,  68 . As such, the drive and the at least one driven gears  62 ,  89  and the first and second selected gears  66 ,  68  may freely rotate within the cavity  58  without excessive gaps  134  between the gears and the housing  54 . The nominal gap  134  reduces the amount of material required to the produce the housing  54 . 
     In one embodiment, the first and second selected gears  66 ,  68  are both selectively rotatably coupled to the housing  54  at one of the first and second gear retention features  70 ,  72 . Moreover, only of the first and second gear retention features  70 ,  72  may be defined by the internal surface  56  of the housing  54 . 
     In order to facilitate engagement of the first selected gear  66  and the second selected gear  68  with both of the drive gear  62  and the at least one driven gear  89  (more specifically, the first driven gear  89  when the second driven gear  90  is present as shown in  FIGS. 11 and 12 ), the at least one driven gear  89  includes one of a first selected first driven gear  89   a  engageable with the first selected gear  66  (as shown in  FIG. 11 ) and a second selected first driven gear  89   b  engageable with the second selected gear  68  (as shown in  FIG. 12 ) to transmit rotation from the drive gear  62  to one of the first and second selected first driven gears  89   a,    89   b.  As such, the first selected gear  66  is engageable with both the drive gear  62  and the first selected first driven gear  89   a  while the second selected gear  68  is engageable with both the drive gear  62  and the second selected first drive driven gear  89   b.  Moreover, as shown in  FIGS. 11 and 12 , the first and second selected first driven gears  89   a,    89   b  may each independently engage the second driven gear  90 , as described. One having skill in the art will appreciate that the second driven gear  90  may be absent such that the selected one of the first and second selected first driven gears  89   a,    89   b  may operably coupled to the output shaft  88 . 
     The above description of the housing  52  (aside from defining only one of the first and second gear retention features  70 ,  72 ) is applicable to the present embodiment. Moreover, the above description of the first and second selected gears  66 ,  68  is applicable to the present embodiment. For example, the first selected gear  66  may have the first and second gear sections  94 ,  96  having the gear teeth  102 ,  106  and the first and third diameters D 1 , D 3 , as described above, while the second selected gear  68  may have the first and second gear sections  98 ,  100  having the gear teeth  104 ,  108  and the second and fourth diameters D 2 , D 4 , as described above and generally shown in  FIGS. 11 and 12 . 
     Moreover, the description above of the first driven gear  89  is generally applicable to the first and second selected first driven gears  89   a,    89   b.  For example, the first and second selected first driven gears  89   a,    89   b  may have the first and second gear sections  84 ,  86  having the gear teeth  82 , as shown in  FIGS. 11 and 12 . However, the the first and second selected first driven gears  89   a ,  89   b  differ from the first driven gear  89  in that first gear section  84  of the first selected first driven gear  89   a  has a first output diameter OD 1  and the first gear section  86  of the second selected first driven gear  89   b  has a second output diameter OD 2 , which is different than the first output diameter OD 1 . 
     The diameters associated with the drive gear  62 , the first and second selected gears  66 ,  68 , and the first and second selected first driven gears  89   a,    89   b  are designed to ensure engagement of the drive gear  62 , the first selected gear  66 , and the first selected first driven gear  89   a  in one configuration and engagement of the drive gear  62 , the second selected gear  68 , and the second selected first driven gear  89   b  in another configuration while both configurations utilize the first gear retention feature  70  of the housing  52  for both the first and second selected gears  66 ,  68 . Said differently, the drive  62  gear having the input diameter ID is configured to engage both the first gear section  94  of the first selected gear  66  having the first diameter D 1  (as shown in  FIG. 11 ) and the first gear section  98  of the second selected gear  68  having the second diameter D 2  (as shown in  FIG. 12 ), as described above. Furthermore, the second gear section  96  of the first selected gear  66  having the third diameter D 3  is configured to engage the first gear section  84  of the first selected first driven gear  89   a  having the first output diameter OD 1  (as shown in  FIG. 11 ) while the second gear section  100  of the second selected gear  68  having the fourth diameter D 4  is configured to engage the first gear section  84  of the second selected first driven gear  89   b  having the second output diameter OD 2  (as shown in  FIG. 12 ). 
     As such, the drive gear  62 , the first selected gear  66 , and the first selected first driven gear  89   a  have the first gear ratio for selectively moving the output shaft  88  with the first output. Likewise, the drive gear  62 , the second selected gear  68 , and the second selected first driven gear  89   b  have the second gear ratio for selectively moving the output shaft  88  with the second output. 
     The subject invention further provides for a method of manufacturing the gear drive assembly  52  for use with and driven by the motor  50  in the actuator  48 . As described above, the actuator  48  is capable of moving the output shaft  88  between the plurality of positions, with the actuator  48  having the one of the first output, having the first velocity and the first torque, and the second output, having the second velocity and the second torque. As shown in  FIGS. 6 and 7 , the gear drive assembly  52  comprises the housing  54  having the internal surface  56  defining the cavity  58 , and the gear arrangement  60  disposed in the cavity  58  and comprising the drive gear  62 , the at least one driven gear  89 , and the one of the first selected gear  66  and the second selected gear  68 . The drive and the at least one driven gears  62 ,  89  and the first selected gear  66  have the first gear ratio for selectively moving the output shaft  88  with the first output. The drive and the at least one driven gears  62 ,  89  and the second selected gear  68  have the second gear ratio not equal to the first gear ratio for selectively moving the output shaft  88  with the second output. 
     The method comprises the steps of rotatably coupling the drive and the at least one driven gears  62 ,  89  with the housing  54  within the cavity  58 , selecting one of the first selected gear  66  (as shown in  FIG. 6 ) and the second selected gear  68  (as shown in  FIG. 7 ), engaging the one of the first and second selected gears  66 ,  68  with both of the drive and the at least one driven gears  62 ,  89 , and rotatably coupling the one of the first and second selected gears  66 ,  68  with the housing  54  within the cavity  58 . 
     As described above and generally shown in  FIG. 5 , the internal surface  56  of the housing  54  defines the first gear retention feature  70  to facilitate selective rotatable coupling of the first selected gear  66  with the housing  54  and the second gear retention feature  72  to facilitate selective rotatable coupling of the second selected gear  68  with the housing  54 . As such, the step of rotatably coupling the one of the first and second selected gears  66 ,  68  with the housing  54  may be further defined as the step of rotatably coupling the one of the first and second selected gears  66 ,  68  with the respective one of the first and second gear retention features  70 ,  72 . 
     As further described above, each of the first and second selected gears  66 ,  68  may define the hole  116  extending therethrough, and the internal surface  56  of the housing  54  may defines the pair of first gear pockets  118  as the first gear retention feature  70  and the pair of second gear pockets  120  as the second gear retention feature  72 . As such, the step of rotatably coupling the one of the first and second selected gears  66 ,  68  with the respective one of the first and second gear retention features  70 ,  72  may be further defined as the steps of inserting the pin  122  through the hole  116  of the one of the first and second selected gears  66 ,  68  and inserting the pin  122  into the respective one of the pair of first gear pockets  118  and the pair of second gear pockets  120 . 
     As described above, the at least one driven gear  89  includes one of a first selected first driven gear  89   a  engageable with the first selected gear  66  (shown in  FIG. 11 ) and a second selected first driven gear  89   b  engageable with the second selected gear  68  (shown in  FIG. 12 ) to transmit rotation from the drive gear  62  to one of the first and second selected first driven gear  89   a ,  89   b.  The method may further include the step of selecting one of the first and second selected first driven gears  89   a,    89   b  corresponding with the selected one of the first and second selected gears  66 ,  68 . Furthermore, the step of engaging the one of the first and second selected gears  66 ,  68  with both of the drive gear  62  and the at least one driven gears  89  may be further defined as engaging the one of the first and second selected gears  66 ,  68  with both of the drive gear  62  and the respective one of the first and second selected first driven gears  89   a,    89   b.    
     The gear drive assembly  52  allows for different properties (i.e., the first and second outputs) by selecting between the first and second selected gears  66 ,  68 . The housing  54  is correspondingly designed to accommodate each of the first and second selected gears  66 ,  68 . As such, only one housing is needed to accommodate two different outputs. Because one housing is needed rather than two, manufacturing costs are reduced. 
     The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. As is now apparent to those skilled in the art, many modifications and variations of the subject invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, wherein reference numerals are merely for convenience and are not to be in any way limiting, the invention may be practiced otherwise than as specifically described.