Patent Publication Number: US-2021172519-A1

Title: Method of operating a shifting system for a vehicle transmission

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to and all the benefits of U.S. Provisional Patent Application No. 62/946,156 filed on Dec. 10, 2019, and 63/091,762 filed on Oct. 14, 2020, which are expressly incorporated herein by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to a method of operating a shifting system for a vehicle transmission. 
     2. Description of the Related Art 
     Conventional vehicles known in the art typically include a motor having a rotational output as a rotational input into a vehicle transmission. The motor is typically an internal combustion engine or an electric motor, and generates the rotational output which is selectively transferred to the vehicle transmission which, in turn, transfers rotational torque to one or more wheels of the vehicle. The vehicle transmission changes the rotational speed and torque generated by the motor through a series of predetermined gearsets, whereby changing between the gearsets enables the vehicle to travel at different vehicle speeds for a given motor speed. Commonly, the motor is the electric motor coupled to the vehicle transmission in an axle connected to the wheels of the vehicle. 
     Rotational input into the vehicle transmission typically requires a shifting system to selectively transfer torque to the components of the vehicle transmission. A typical shifting system includes an input member (e.g. the rotational output from the motor) rotatable about an axis, a disconnect coupled to the input member, and an output member (e.g. the rotational input to the vehicle transmission) selectively rotatable with the input member about the axis. A shifting assembly is also typically required to selectively rotatably couple the input member and the output member. 
     The shifting systems known in the art often suffer from in high drag losses, which lowers the efficiency of torque transfer between the motor and the vehicle transmission. Additionally, typical shifting systems produce rough engagement between the motor and the components of the vehicle transmission through connection with the disconnect, resulting in vibrations of the vehicle and an uncomfortable driving experience. 
     Accordingly, it is desirable to provide an improved shifting system for vehicle transmissions. 
     SUMMARY OF THE INVENTION AND ADVANTAGES 
     A shifting system for a vehicle transmission includes an input member extending along an axis between a first end and a second end spaced from the first end. The vehicle transmission has a gearset including a first gear ratio and a second gear ratio different from the first gear ratio. The input member is rotatable about the axis. The shifting system further includes a clutch coupled to the input member. The clutch is configured to selectively allow torque to be transmitted through one of the first and second gear ratios of the gearset from the input member. 
     The shifting system also includes a disconnect coupled to the input member. The disconnect is movable between a first disconnect position and a second disconnect position. The shifting system further includes an output member is spaced from the input member, and the output member is selectively rotatable with the input member about the axis to selectively transmit torque through the other of the first and second gear ratios of the gearset. 
     The shifting system further includes a shifting assembly for selectively rotatably coupling the input member and the output member. The shifting assembly includes an input hub coupled to the input member. The input hub has a disconnectable component engageable with the disconnect, and the disconnectable component of the input hub is disengaged from the disconnect when the disconnect is in the first disconnect position and the disconnectable component of the input hub is engaged with the disconnect when the disconnect is in the second disconnect position. 
     The input hub has a clutch engagement component. The shifting assembly also includes a plurality of clutch plates is coupled to the clutch engagement component of the input hub. The plurality of clutch plates is movable between an engaged position and a disengaged position. In the engaged position, the clutch plates are engaged with one another. In the disengaged position, the clutch plates are disengaged from one another. The shifting assembly further includes a clutch plate carrier is coupled to the plurality of clutch plates and to the output member to transmit torque from the clutch engagement component of the input hub, through the plurality of clutch plates and the clutch plate carrier, to the output member. 
     Accordingly, the shifting system results in low drag losses, which increases the efficiency of torque transfer between a motor and the vehicle transmission. Moreover, the shifting system produces smooth engagement between the motor and the vehicle transmission through the shifting assembly (i.e., through the connection with the disconnect and engagement of the plurality of clutch plates), resulting in fewer vibrations and a more comfortable driving experience. Furthermore, the clutch allows the shifting system to achieve low spin losses by rotatably decoupling the shifting assembly when torque is not required to be transmitted through the shifting assembly. The low spin losses allowed by the combination of the clutch and the shifting assembly allow the first and second gear ratios of the vehicle transmission to achieve a net energy savings as compared to a single speed transmission. 
     A method of operating the shifting system for the vehicle transmission includes the step of disengaging the clutch to prevent torque from being transmitted through one of the first and second gear ratios from the input member. The method also includes the step of moving the clutch plates from an engaged position, where the clutch plates are engaged with one another, to a disengaged position, where the clutch plates are disengaged from one another. The method further includes the step of moving the disconnect from a first disconnect position, where the disconnectable component of the input hub is disengaged from the disconnect, to a second disconnect position, where the disconnectable component of the input hub is engaged with the disconnect. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other advantages of the present 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 wherein: 
         FIG. 1A  is a schematic illustration of a vehicle transmission for a vehicle, the vehicle transmission including a shifting system having a shift drum, an actuator, an electric motor, an input member, a clutch coupled to the input member for selectively transmitting torque through a first gear ratio, and a shifting assembly coupled to the input member for selectively transmitting torque through a second gear ratio; 
         FIG. 1B  is a schematic illustration of the vehicle transmission including first and second shift drums, first and second actuators, and first and second electric motors, with the clutch coupled to the input member and the shifting assembly coupled to the input member; 
         FIG. 1C  is a schematic illustration of the vehicle transmission including a third shift drum, a third actuator, and a third electric motor, with the clutch coupled to the input member and the shifting assembly coupled to the input member; 
         FIG. 1D  is a schematic illustration of the vehicle transmission including the shift drum, the actuator, the electric motor, and a countershaft, and with the clutch coupled to the input member and the shifting assembly coupled to the countershaft; 
         FIG. 1E  is a schematic illustration of the vehicle transmission including the first and second shift drums, the first and second actuators, and the first and second electric motors, with the clutch coupled to the input member and the shifting assembly coupled to the countershaft; 
         FIG. 1F  is a schematic illustration of the vehicle transmission including the third shift drum, the third actuator, and the third electric motor, with the clutch coupled to the input member and the shifting assembly coupled to the countershaft; 
         FIG. 2A  is a schematic illustration of the vehicle transmission including the shift drum, the actuator, the electric motor, and the countershaft, with the clutch coupled to the countershaft and the shifting assembly coupled to the input member; 
         FIG. 2B  is a schematic illustration of the vehicle transmission, with first and second shift drums, first and second actuators, and first and second electric motors, and with the clutch coupled to the countershaft and the shifting assembly coupled to the input member; 
         FIG. 2C  is a schematic illustration of the vehicle transmission, with the third shift drum, the third actuator, and the third electric motor, and with the clutch coupled to the countershaft and the shifting assembly coupled to the input member; 
         FIG. 2D  is a schematic illustration of the vehicle transmission including the shift drum, the actuator, the electric motor, and the countershaft, with the clutch coupled to the countershaft and the shifting assembly coupled to the countershaft; 
         FIG. 2E  is a schematic illustration of the vehicle transmission, with the first and second shift drums, the first and second actuators, and the first and second electric motors, and with the clutch coupled to the countershaft and the shifting assembly coupled to the countershaft; 
         FIG. 2F  is a schematic illustration of the vehicle transmission, with the third shift drum, the third actuator, and the third electric motor, and with the clutch coupled to the countershaft and the shifting assembly coupled to the countershaft; 
         FIG. 3  is a schematic illustration of a shifting schedule for the shifting system of the vehicle transmission, with X/X denoting a first clutch position, X/O denoting a second clutch position, O/O denoting a third clutch position, O/X denoting a fourth clutch position, DP 1  denoting a first disconnect position, DP 2  denoting a second disconnect position, ENG denoting an engaged position of the clutch plates of the shifting assembly, and D-ENG denoting a disengaged position of the clutch plates; 
         FIG. 4A  is a perspective view of a selectable one-way clutch, with the selectable one-way clutch being of the stationary variety and with the selectable one-way clutch having an inner race, an outer race, a plurality of pawls circumferentially spaced from one another, and an actuator ring coupled to the pawls; 
         FIG. 4B  is a perspective view of the selectable one-way clutch, with the selectable one-way clutch being of the rotating variety; 
         FIG. 4C  is a cross-sectional view of the selectable one-way clutch of  FIG. 4B ; 
         FIG. 5A  is a cross-section view of the shifting assembly having an apply plate and a plurality of clutch plates, with the disconnect in the first disconnect position where the disconnect is disengaged with an input hub of the shifting assembly, and the apply plate is in the first plate position where the plurality of clutch plates are in the engaged position; 
         FIG. 5B  is a cross-section view of the shifting assembly, with the disconnect in the first disconnect position where the disconnect is disengaged with the input hub, and the apply plate is in the second plate position where the plurality of clutch plates are in the disengaged position; 
         FIG. 5C  is cross-sectional view of the shifting assembly, with the disconnect in the second disconnect position where the disconnect is engaged with the input hub, and the apply plate is in the second plate position where the plurality of clutch plates are in the disengaged position; 
         FIG. 5D  is a cross-sectional view of the shifting assembly, with the disconnect in the second disconnect position where the disconnect is engaged with the input hub, and the apply plate is in the first disconnect position where the plurality of clutch plates are in the engaged position; 
         FIG. 6A  is a cross-section view of the shifting assembly, with the disconnect being a synchronizer, and with the disconnect in the first disconnect position where the disconnect is disengaged with an input hub, and the apply plate is in the first plate position where the plurality of clutch plates are in the engaged position; 
         FIG. 6B  is a cross-section view of the shifting assembly, with the disconnect being a synchronizer, and with the disconnect in the first disconnect position where the disconnect is disengaged with the input hub, and the apply plate is in the second plate position where the plurality of clutch plates are in the disengaged position; 
         FIG. 6C  is a cross-sectional view of the shifting assembly, with the disconnect being a synchronizer, and with the disconnect in the second disconnect position where the disconnect is engaged with the input hub, and the apply plate is in the second plate position where the plurality of clutch plates are in the disengaged position; 
         FIG. 6D  is a cross-sectional view of the shifting assembly, with the disconnect being a synchronizer, and with the disconnect in the second disconnect position where the disconnect is engaged with the input hub, and the apply plate is in the first disconnect position where the plurality of clutch plates are in the engaged position; 
         FIG. 7A  is a cross-section view of the shifting assembly, with the disconnect in the first disconnect position where the disconnect is disengaged with the input hub, and the apply plate is in the first plate position where the plurality of clutch plates are in the engaged position; 
         FIG. 7B  is a cross-section view of the shifting assembly, with the disconnect in the first disconnect position where the disconnect is disengaged with the input hub, and the apply plate is in the second plate position where the plurality of clutch plates are in the disengaged position; 
         FIG. 7C  is a cross-sectional view of the shifting assembly, with the disconnect in the second disconnect position where the disconnect is engaged with the input hub, and the apply plate is in the second plate position where the plurality of clutch plates are in the disengaged position; 
         FIG. 7D  is a cross-sectional view of the shifting assembly, with the disconnect in the second disconnect position where the disconnect is engaged with the input hub, and the apply plate is in the first disconnect position where the plurality of clutch plates are in the engaged position; 
         FIG. 8  is a flowchart of a method of operating the shifting system, with the method directed toward shifting transmittance of torque between the first and second gear ratios using the selectable one-way clutch; 
         FIG. 9  is a flowchart of a method of operating the shifting system, with the method directed toward parking the vehicle; 
         FIG. 10  is a flowchart of a method of operating the shifting system, with the method directed toward shifting transmittance of torque between the first and second gear ratios using the clutch; 
         FIG. 11A  is a perspective view of the first shift drum defining a first groove, and a first actuator disposed at least partially in the first groove; 
         FIG. 11B  is a perspective view of the second shift drum defining a second groove, and a second actuator disposed at least partially in the second groove; and 
         FIG. 11C  is a perspective view of the third shift drum defining a third groove, and a third actuator disposed at least partially in the third groove. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With reference to the Figures, wherein like numerals indicate like parts throughout the several views, a vehicle transmission  10  is provided in schematic illustration in  FIGS. 1A-2F . The vehicle transmission  10  has a gearset  12  including a first gear ratio  14  and a second gear ratio  16  different from the first gear ratio  14 . The vehicle transmission  10  includes a shifting system  18 , as shown in  FIGS. 1A-2F . 
     The shifting system  18  includes an input member  20  extending along an axis A between a first end  22  and a second end  24  spaced from the first end  22 . The input member  20  is rotatable about the axis A. As non-limiting examples, the input member  20  may be a shaft or a gear. The shifting system  18  also includes a clutch  25  coupled to the input member  20 . The clutch  25  is configured to selectively allow torque to be transmitted through one of the first and second gear ratios  14 ,  16  of the gearset  12  from the input member  20 . The clutch  25  may be a variety of clutch types and configurations, which are detailed further below. Notably, although not required, the clutch  25  may be a selectable one-way clutch  26 . When present, selectable one-way clutch  26  is rotatably coupled to the input member  20 , and the selectable one-way clutch  26  is movable between a first clutch position (denoted as X/X in  FIG. 3 ), a second clutch position (denoted as X/O in  FIG. 3 ), and a third clutch position (denoted as O/O in  FIG. 3 ). 
     In the first clutch position X/X, as shown in  FIG. 3 , the selectable one-way clutch  26  is configured to allow torque to be transmitted through one of the first and second gear ratios  14 ,  16  of the gearset  12  from the input member  20  in either a first rotational direction D 1  or a second rotational direction D 2  opposite the first rotational direction. In the first clutch position X/X, the selectable one-way clutch  26  is in a lock/lock configuration. In this lock/lock configuration, torque may be transmitted from the input member  20  through one of the first and second gear ratios  14 ,  16  in the first rotational direction D 1 . It is also to be appreciated that torque may be transmitted through one of the first and second gear ratios  14 ,  16  to the input member  20  in the second rotational direction D 2 . In other words, in the first clutch position X/X, torque may be transmitted in either the first rotational direction D 1 , or the second rotational direction D 2 . It is to be appreciated that the first rotational direction D 1  may be clockwise, and the second rotational direction D 2  may be counterclockwise. Alternatively, it is to be appreciated that the first rotational direction D 1  may be counterclockwise, and the second rotational direction D 2  may be clockwise. 
     In the second clutch position X/O, as shown in  FIG. 3 , the selectable one-way clutch  26  is configured to allow torque to be transmitted through one of the first and second gear ratios  14 ,  16  of the gearset  12  from the input member  20  in the first rotational direction D 1  and prevent torque from being transmitted through one of the first and second gear ratios  14 ,  16  of the gearset  12  from the input member  20  in the second rotational direction D 2 . In the second clutch position X/O, the selectable one-way clutch  26  is in a lock/free configuration. In this lock/free configuration, torque may be transmitted from the input member  20  through one of the first and second gear ratios  14 ,  16  in the first rotational direction D 1 . However, torque is prevented from being transmitted through one of the first and second gear ratios  14 ,  16  to the input member  20  in the second rotational direction D 2 . This lock/free configuration is typically referred to as over-running the selectable one-way clutch  26  and assists in shifting transmittance of torque from either through the first gear ratio  14  to the second gear ratio  16 , or through the second gear ratio  16  to the first gear ratio  14 . The second clutch position X/O, therefore, may be referred to as shift ready. 
     In the third clutch position O/O, as shown in  FIG. 3 , the selectable one-way clutch  26  is configured to prevent torque from being transmitted through one of the first and second gear ratios  14 ,  16  of the gearset  12  from the input member  20  in either the first rotational direction D 1  or the second rotational direction D 2 . In the third clutch position O/O, the selectable one-way clutch  26  is in a free/free configuration. In this free/free configuration, torque is prevented from being transmitted from the input member  20  through one of the first and second gear ratios  14 ,  16  in the first rotational direction D 1 . In this free/free configuration, torque is also prevented from being transmitted through one of the first and second gear ratios  14 ,  16  to the input member  20  in the second rotational direction D 2 . The free/free configuration limits drag losses on the shifting system  18  by rotatably decoupling one of the first and second gear ratios  14 ,  16  from the input member  20 . 
     The shifting system  18  also includes a disconnect  28  coupled to the input member  20 . The disconnect  28  is movable between a first disconnect position DP 1 , as shown in  FIGS. 3, 5A, 5B, 6A, 6B, 7A, and 7B , and a second disconnect position DP 2 , as shown in  FIGS. 3, 5C, 5D, 6C, 6D, 7C, and 7D . The shifting system  18  also includes an output member  30  spaced from the input member  20 , and the output member  30  is selectively rotatable with the input member  20  about the axis A to selectively transmit torque through the other of the first and second gear ratios  14 ,  16  of the gearset  12 . 
     The shifting system  18  further includes a shifting assembly  32  for selectively rotatably coupling the input member  20  and the output member  30 . With reference to  FIGS. 5A-7D , the shifting assembly  32  includes an input hub  34  coupled to the input member  20 . The input hub  34  has a disconnectable component  36  engageable with the disconnect  28 , and the disconnectable component  36  of the input hub  34  is disengaged from the disconnect  28  when the disconnect  28  is in the first disconnect position DP 1  and the disconnectable component  36  of the input hub  34  is engaged with the disconnect  28  when the disconnect  28  is in the second disconnect position DP 2 . 
     The disconnect  28  rotatably disconnects the input member  20  and the disconnectable component  36 , thus rotatably disconnecting the input member  20  and the input hub  34 . In one embodiment, the disconnect  28  is a disconnect clutch. Alternatively, in another embodiment, the disconnect  28  is a synchronizer. In the embodiments where the disconnect  28  is a synchronizer, the synchronizer may have a synchronizer ring, a synchronizer cone, a synchronizer hub, and a synchronizer sleeve. In yet another embodiment, the disconnect  28  is a dog clutch. 
     The input hub  34  has a clutch engagement component  38 . The shifting assembly  32  includes a plurality of clutch plates  40  coupled to the clutch engagement component  38  of the input hub  34 . The plurality of clutch plates  40  is movable between an engaged position ENG and a disengaged position D-ENG. In the engaged position ENG, as shown in  FIGS. 3, 5A, 5D, 6A, 6D, 7A, and 7D , the clutch plates  40  are engaged with one another. In the disengaged position D-ENG, as shown in  FIGS. 3, 5B, 5C, 6B, 6C, 7B, and 7C , the clutch plates  40  are disengaged from one another. The shifting assembly  32  also includes a clutch plate carrier  42  is coupled to the plurality of clutch plates  40  and to the output member  30  to transmit torque from the clutch engagement component  42  of the input hub  34 , through the plurality of clutch plates  40  and the clutch plate carrier  42 , to the output member  30 . 
     The shifting system  18  results in low drag losses, which increases the efficiency of torque transfer between a motor and the vehicle transmission  10 . Moreover, the shifting system  18  produces smooth engagement between the motor and the vehicle transmission  10  through the shifting assembly  32  (i.e., through the connection with the disconnect  28  and engagement of the plurality of clutch plates  40 ), resulting in fewer vibrations and a more comfortable driving experience. Furthermore, the clutch  26  allows the shifting system  18  to achieve low spin losses by rotatably decoupling the shifting assembly  32  when torque is not required to be transmitted through the shifting assembly  32 . The low spin losses allowed by the combination of the clutch  26  and the shifting assembly  32  allow the first and second gear ratios  14 ,  16  of the vehicle transmission  10  to achieve a net energy savings as compared to a single speed transmission. 
     As discussed above, it is to be appreciated that the clutch  25  may be a variety of clutch types and configurations. In a non-limiting example, the clutch  25  may be the selectable one-way clutch  26 . However, in other non-limiting examples, the clutch  25  may be another shifting assembly as described herein, may be a dry friction clutch, may be a wet friction clutch, may be a single plate clutch, may be a multi-plate clutch, may be a cone clutch, may be a dog clutch, or may be a centrifugal clutch. Additionally, in some embodiments, at least a portion of the clutch  25  is rotatably coupled with the input member  14 . 
     It is to be appreciated that the motor may be an internal combustion motor or may be an electric motor. It is also to be appreciated that the motor may be coupled to a back axle of the vehicle. In one embodiment, the motor is the electric motor and is rotatably coupled to the back axle of the vehicle and configured to rotate the back axle of the vehicle to propel the vehicle. 
     The selectable one-way clutch  26  may have an inner race  44  and an outer race  46  disposed about the inner race  44 , as shown in  FIGS. 4A-4C . The inner race  44  and the outer race  46  may be concentric with one another. In one embodiment, as shown in  FIGS. 1A-1F , the inner and outer races  44 ,  46  of the selectable one-way clutch  26  may be disposed about and aligned axially with the input member  20 . The inner race  44  of the selectable one-way clutch  26  may be rotatably coupled with the input member  20 . The inner race  44 , in a non-limiting example, may be splined to the input member  20  such that rotation of the input member  20  results in rotation of the inner race  44  of the selectable one-way clutch  26 . Additionally, or alternatively, the inner race  44  of the selectable one-way clutch  26  may be bolted to, or otherwise mechanically fastened to, the input member  20 . 
     The selectable one-way clutch  26  may also have at least one pawl  48  disposed between the inner race  44  and the outer race  46 . The pawl  48  selectively rotatably couples the inner race  44  and the outer race  46 . In a non-limiting example, the pawl  48  may be rotatable to engage both the inner race  44  and the outer race  46  to prevent relative rotation between the inner race  44  and the outer race  46 . It is to be appreciated that the pawl  48  may allow rotational coupling between the inner race  44  and the outer race  46  in the first rotational direction D 1  while preventing rotational coupling between the inner race  44  and the outer race  46  in the second rotational direction D 2 . Alternatively, it is to be appreciated that the pawl  48  may allow rotational coupling between the inner race  44  and the outer race  46  in the second rotational direction D 2  while preventing rotational coupling between the inner race  44  and the outer race  46  in the first rotational direction D 1 . The pawl  48  may also either prevent, or allow, rotational coupling between the inner race  44  and the outer race  46  in both the first rotational direction D 1  and the second rotational direction D 2 . 
     The at least one pawl  48  may be further defined as a plurality of pawls  50  circumferentially spaced from one another. The selectable one-way clutch  26  may further include an actuator ring  52  coupled to the plurality of pawls  50  for selectively rotatably locking the inner and outer races  44 ,  46  together. The actuator ring  52  may be in physical contact with the pawls  50  such that movement, for example rotation, of the actuator ring  52  results in movement, for example rotation, of the pawls  50 . The actuator ring  52  may be electrically actuated by a small electric motor or solenoid. The small electric motor or solenoid may be coupled to the outer race  46  of the selectable one-way clutch  26 . It is also to be appreciated that the actuator ring  52  may be hydraulically, pneumatically, or otherwise actuated. 
     The shifting assembly  32  may further include a biasing member  54  coupled to the plurality of clutch plates  40  to bias the plurality of clutch plates  40  toward the engaged position ENG. In other words, the plurality of clutch plates  40  may be normally closed and at rest in the engaged position ENG. Because the plurality of clutch plates  40  of the shifting assembly  32  at rest are in the engaged position ENG due to the biasing member  54  biasing the plurality of clutch plates  40  toward the engaged position ENG, the shifting assembly  32  is energy efficient, and thus the shifting system  18  is also energy efficient. Said differently, because power from an electronic actuator or a hydraulic actuator is not needed to maintain the plurality of clutch plates  40  in the engaged position ENG, the shifting assembly  32  is energy efficient, and thus the shifting system  18  is energy efficient. 
     The shifting assembly  32  may further include an apply plate  56  coupled to the biasing member  54 . When present, the apply plate  56  is movable between a first plate position where the plurality of clutch plates  40  are in the engaged position ENG, and a second plate position where the apply plate  56  is engaged with the biasing member  54  and the plurality of clutch plates  40  are in the disengaged position D-ENG. 
     In one embodiment, the apply plate  56  and the disconnect  28  are movable independent of one another. The apply plate  56  may be moved from the first plate position to the second plate position, resulting in the plurality of clutch plates  40  moving from the engaged position ENG to the disengaged position D-ENG, independent of whether the disconnect  28  is in the first disconnect position DP 1  or the second disconnect position DP 2  and without affecting the position of the disconnect  28 . Likewise, the disconnect  28  may be moved from the first disconnect position DP 1  to the second disconnect position DP 2 , resulting in the input hub  34  being engaged, independent of whether the apply plate  56  is in the first plate position or the second plate position and without affecting the position of the apply plate  56 . 
     In the embodiment where the apply plate  56  and the disconnect  28  are movable independent of one another, the shifting system  18  may also include a first actuator coupled to the disconnect  28  to move the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2  independent of the apply plate  56 , and a second actuator coupled to the apply plate  56  to move the apply plate  56  from the first plate position to the second plate position independent of the disconnect  28 . It is to be appreciated that the first and second actuators may be moved through, but not limited to, mechanical actuation, electrical actuation, hydraulic actuation, or pneumatic actuation. 
     In some embodiments, the input member  20  is rotatably coupled to the output member  30  when the disconnect  28  is in the second disconnect position DP 2  and the apply plate  56  is in the first plate position. In other words, the input member  20  may be rotatably coupled to the output member  30  when the apply plate  56  is in the first plate position where the biasing member  54  is able to bias the plurality of clutch plates  40  toward the engaged position ENG, and when the disconnect  28  is in the second disconnect position DP 2  where the disconnect  28  is engaged with the input hub  34 . In these positions, torque is able to be transmitted from the input member  20 , through the input hub  34 , the plurality of clutch plates  40 , and the clutch plate carrier  42  to the output member  30 . 
     In some embodiments, the input member  20  is rotatably decoupled from the output member  30  when the disconnect  28  is in the first disconnect position DP 1  and/or when the apply plate  56  is in the second plate position. In other words, the input member  20  is rotatably decoupled from the output member  30  when either the disconnect  28  is in the first disconnect position DP 1 , the apply plate  56  is in the second plate position, or both the disconnect  28  is in the first disconnect position DP 1  and the apply plate  56  is in the second plate position. In these positions, torque is unable to be transferred from the input member  20  to the output member  30 . 
     The disconnect  28  and the plurality of clutch plates  40  are disposed in series with one another in the embodiments where the input member  20  is rotatably coupled to the output member  30  only when the disconnect  28  is in the second disconnect position DP 2  and the apply plate  56  is in the first plate position. Said differently, if either the disconnect  28  is in the first disconnect position DP 1  where the disconnect  28  is disengaged from the input hub  34 , or the apply plate  56  is in the second plate position where the plurality of clutch plates  40  are disengaged, then the input member  20  is rotatably decoupled from the output member  30 . Therefore, when disposed in series, both the disconnect  28  must be engaged with the input hub  34  and the plurality of clutch plates  40  must be engaged with one another to transfer torque directly from the input member  20  to the output member  30 . 
     The disconnectable component  36  of the input hub  34  and the clutch engagement component  42  of the input hub  34  may be integral with one another. Alternatively, the disconnectable component  36  of the input hub  34  and the clutch engagement component  42  of the input hub  34  may be separate components. In some embodiments, the clutch engagement component  42  of the input hub  34  may be rotatably connected to the disconnectable component  36  of the input hub  34  through use of keys, tabs, or bolts. It is to be appreciated that the input hub  34  may be more than two components and may include a third component or more to transmit torque from the input member  20  to the plurality of clutch plates  40 . 
     In some embodiments, as shown in  FIGS. 5A-6D , the shifting assembly  32  further includes an intermediate apply plate  58  coupled to the apply plate  56  such that the apply plate  56  is disposed between the intermediate apply plate  58  and the biasing member  54 . The apply plate  56  is contactable by the intermediate apply plate  58  in the first plate position to engage the plurality of clutch plates  40 . In this embodiment, the intermediate apply plate  58  transmits force to the apply plate  56 , and thus to the biasing member  54 , to move the biasing member  54  and result in the plurality of clutch plates  40  being in the disengaged position D-ENG. It is to be appreciated that the intermediate apply plate  58  may also be commonly referred to as a release plate. 
     Although not required, the shifting assembly  32  may also include a support ring  60  disposed between the biasing member  54  and the clutch engagement component  42  to support the plurality of clutch plates  40 . The support ring  60  may be disposed about the axis A and may be rotatable with either the input member  20  or the output member  30 . The support ring  60  may be spaced from the plurality of clutch plates  40  along the axis A, as shown in  FIGS. 7A-7D , and may be rotatably coupled to the clutch plate carrier  42 . 
     In some embodiments, as shown in  FIGS. 7A-7D , the biasing member  54  is spaced from the clutch engagement component  42  of the input hub  34  and the clutch plate carrier  42  along the axis A such that the clutch engagement component  42  of the input hub  34  is disposed between the biasing member  54  and the clutch plate carrier  42 . In this embodiment, the support ring  60  is disposed between the biasing member  54  and the plurality of clutch plates  40 , is disposed between the biasing member  54  and the clutch engagement component  42  of the input hub  34 . 
     In other embodiments, as shown in  FIGS. 7A-7D , the clutch engagement component  42  of the input hub  34  is spaced from the biasing member  54  and the clutch plate carrier  42  along the axis A such that the biasing member  54  is disposed between the clutch engagement component  42  of the input hub  34  and the clutch plate carrier  42 . In this embodiment, the support ring  60  is disposed between the biasing member  54  and the clutch engagement component  42 . 
     In some embodiments, the biasing member  54  is a Belleville spring. It is to be appreciated, however, that the biasing member  54  may be any type of spring, including, but not limited to, a wave spring, a coil spring, and a conical spring. 
     As shown in  FIGS. 5A-6D , the output member  30  may be spaced from the input member  20  along the axis A. In the embodiments where the output member  30  is spaced from the input member  20  along the axis A, the input member  20  may be a shaft, and the output member  30  may also be a shaft. In this embodiment, the output member  30  may be the sole output of the shifting system  18 . 
     It is to be appreciated that in the embodiments illustrated in  FIGS. 5A-6D , the apply plate  56  may translate along the axis from the first plate position to the second plate position to translate the biasing member  54  along the axis. In doing so, the plurality of clutch plates  40  is moved from the engaged position ENG to the disengaged position D-ENG. 
     As shown in  FIGS. 7A-7D , the output member  30  may be radially spaced from and disposed about the input member  20 . In the embodiments where the output member  30  is radially spaced from and disposed about the input member  20 , the output member  30  may be one of at least two outputs of the shifting system  18 . Another output other than the output member  30  itself may be the input member  20 . Said differently, if the disconnect  28  is in the first disconnect position DP 1  or the apply plate  56  is in the second plate position, the input member  20  may still be able to transfer torque. It is to be appreciated that the output member  30  may be a gear in the embodiments where the output member  30  is radially spaced from and disposed about the input member  20 . 
     It is to be appreciated that in the embodiments illustrated in  FIGS. 7A-7D , the biasing member  54  may pivot about a pivot point of the biasing member  54  when a section of the apply plate  56  closest to the input member  20  is translated along the axis A. In doing so, a section of the apply plate  56  furthest from the input member  20  is moved away from the plurality of clutch plates  40 , and the plurality of clutch plates  40  is moved from the engaged position ENG to the disengaged position D-ENG. It is to be appreciated that the pivot point at which the biasing member  54  may pivot is shown where the support ring  60  and an additional backing plate both contact the biasing member  54 . The areas of contact of the support ring  60  and additional backing plate where the support ring  60  and/or the additional backing plate contact the biasing member  54  may be hardened against wear. 
     In some embodiments, the selectable one-way clutch  26  is further movable between a fourth position, as shown in  FIGS. 3 , where the selectable one-way clutch  26  is configured to allow torque to be transmitted through one of the first and second gear ratios  14 ,  16  of the gearset  12  from the input member  20  in the second rotational direction D 1  and prevent torque from being transmitted through one of the first and second gear ratios  14 ,  16  of the gearset  12  from the input member  20  in the first rotational direction D 1 . The selectable one-way clutch  26 , in these embodiments, is typically referred to as a four-mode clutch. It is also to be appreciated that the selectable one-way clutch  26  may also be referred to as a multi-mode clutch module. An example of a multi-mode clutch module is described in U.S. Pat. No. 9,151,345 (filed on Jun. 2, 2014 and issued on Oct. 6, 2015), U.S. Pat. No. 9,726,236 (filed on Jan. 27, 2014 and issued on Aug. 8, 2017), U.S. Pat. No. 10,151,359 (filed May 24, 2016 and issued on Dec. 11, 2018), the disclosures of which are incorporated by reference in their entirety. 
     In the embodiments where the selectable one-way clutch  26  is movable to a fourth clutch position (denoted as O/X in  FIG. 3 ), the shifting system  18  may allow regeneration of the electric motor. More specifically, the shifting system  18  may allow regenerative braking. Torque may be transferred from one of the first and second gear ratios  14 ,  16  through the selectable one-way clutch  26  in the fourth clutch position O/X, and/or the shifting assembly, to the electric motor. In this instance, the electric motor may be a generator which converts rotational movement of the input member  20  to electrical energy. 
     The vehicle transmission may also include a countershaft  62  spaced from the input member  20  and rotatable about the axis A. It is to be appreciated that the countershaft  62  may also be referred to as a layshaft  62 . The clutch  26  may be configured to transmit torque from the input member  20  to the countershaft  62  through the first gear ratio  14 . The shifting assembly  32  may be configured to transmit torque from the output member  30  to the countershaft  62  through the second gear ratio  16 . It is to be appreciated that the output member  30  may be a shaft, a gear, or even the countershaft  62  itself. 
     It is to be appreciated that the inner and outer races  44 ,  46  of the selectable one-way clutch  26  may be disposed about and aligned axially with the input member  20 , as shown in  FIGS. 1A-1F . It is also to be appreciated that, in the embodiments where the inner and outer races  44 ,  46  of the selectable one-way clutch  26  is disposed about and aligned axially with the input member  20 , the shifting assembly  32  may either be coupled to the input member  20 , as shown in  FIGS. 1A-1C , or coupled to the countershaft  62 , as shown in  FIGS. 1D-1F . 
     In another embodiment, as shown in  FIGS. 2A-2F , the inner and outer races  44 ,  46  of the selectable one-way clutch  26  are disposed about and aligned axially with the countershaft  62 . In this embodiment, the input member  20  extends directly from the motor to the shifting assembly  32 . However, it is to be appreciated that the input member  20  may be solid, unitary, and one-piece in either, or both, embodiments where the selectable one-way clutch  26  is disposed about and aligned axially with either the input member  20  or the countershaft  62 . It is also to be appreciated that, in the embodiments where the inner and outer races  44 ,  46  of the selectable one-way clutch  26  is disposed about and aligned axially with the countershaft  62 , the shifting assembly  32  may either be coupled to the input member  20 , as shown in  FIG. 2A-2C , or coupled to the countershaft  62 , as shown in  FIG. 2D-2F . 
     As shown in  FIGS. 1A, 2A, 1D, and 2D , the shifting system may also include a shift drum  64  operatively connected to at least one of the clutch  25  and the shifting assembly  32 . In other words, the shift drum  64  may be operatively connected to the clutch  25 , to the shifting assembly  32 , or to both the clutch  25  and the shifting assembly  32 . The shift drum  64  may be configured to selectively transmit torque through at least one of the clutch  25  and the shifting assembly  32 . The shift drum  64  is configured to selectively transmit torque through the component(s) that the shift drum  64  is operatively connected to. Said differently, in the embodiments where the shift drum  64  is operatively coupled to the clutch  25 , the shift drum  64  is configured to selectively transmit torque through the clutch  25 . Moreover, in the embodiments where the shift drum  64  is operatively coupled to the shifting assembly  32 , the shift drum  64  is configured to selectively transmit torque through the shifting assembly  32 . In the embodiments where the shift drum  64  is operatively connected to both the clutch  25  and the shifting assembly  32 , the shift drum  64  is configured to selectively transmit torque through both the clutch  25  and the shifting assembly  32 . 
     As shown in  FIG. 11A , the shift drum  64  may define at least one groove  66 . The shifting system  18  may include an actuator  68  disposed at least partially in the groove  66 . The actuator  68  is movable within the groove  66  of the shift drum  64 , which affects the relative position of the actuator  68  as compared to the clutch  25  and/or the shifting assembly  32 . As a non-limiting example, the actuator  68  may be movable within the groove  66  of the shift drum  64  such that the clutch plates  40  may be moved between the engaged position ENG and the disengaged position D-ENG. Moreover, the actuator  68  may be movable within the groove  66  of the shift drum  64  such that the disconnect  28  may be moved between the first disconnect position DP 1  and the second disconnect position DP 2 . It is to be appreciated, however, that the actuator  68  may be movable within the groove  66  of the shift drum  64  such that both the clutch plates  40  may be moved between the engaged position ENG and the disengaged position D-ENG while also moving the disconnect  28  between the first disconnect position DP 1  and the second disconnect position DP 2 . 
     The shift drum  64  may also be further defined as a first shift drum  70  operatively connected to the clutch  25  and configured to selectively transmit torque through the clutch  25 . In this embodiment, the actuator  68  is further defined as a first actuator  72  directly coupled to the shift drum  64  and to the clutch  25  for selectively transmitting torque through the clutch  25 . The first actuator  72  may be at least partially disposed in the at least one groove  66  of the shift drum  64  and configured to selectively transmit torque through the clutch  25 . It is to be appreciated that the at least one groove  66  may be a first groove  66 . 
     As shown in  FIGS. 1B, 1E, 2B, and 2E , the shifting system  18  may also include a second shift drum  74  operatively connected to the shifting assembly  32  and configured to selectively transmit torque through the shifting assembly  32 . The shifting system  18  may further include a second actuator  76  directly coupled to the shifting assembly  32  and configured to selectively transmit torque through the shifting assembly  32 . It is to be appreciated that the second actuator  76  may be directly coupled to the plurality of clutch plates  40 , the apply plate  56  which is movable between the first and second plate positions to affect the movement of the plurality of clutch plates  40  between the engaged ENG and disengaged positions, and/or the intermediate apply plate  58  coupled to the apply plate  56 . It is also to be appreciated that the second actuator  76  may be directly coupled to the disconnect  28  and/or disconnectable component  36  of the shifting assembly  32 . Moreover, the second shift drum  74  may define a second groove  78 , as shown in  FIG. 11B , and the second actuator  76  may be at least partially disposed in the second groove  78  of the second shift drum  74 . The second actuator  76  may be configured to selectively transmit torque through the shifting assembly  32 . 
     In one embodiment, the second actuator  76  is directly coupled (e.g., in direct contact with) with the plurality of clutch plates  40  of the shifting assembly  32 . As discussed above, however, it is to be appreciated that the second actuator  76  may be in direct contact with the apply plate  56  and/or the intermediate apply plate  58  while still being directly coupled to plurality of clutch plates  40 . The second actuator  76  may be movable within the second groove  78  of the second shift drum  74  such that the plurality of clutch plates  40  is moved between the engaged position ENG to the disengaged position D-ENG. In another embodiment, the second actuator  76  is directly coupled with the disconnect  28  and/or the disconnectable component  36  of the shifting assembly  32 . The second actuator may be movable within the second groove  78  of the second shift drum  74  such that the disconnect  28  may be moved between the first disconnect position DP 1  and the second disconnect position DP 2 . It is to be appreciated, however, that the second actuator  76  may be movable within the second groove  78  of the second shift drum  74  such that both the clutch plates  40  may be moved between the engaged position ENG and the disengaged position D-ENG while also moving the disconnect  28  between the first disconnect position DP 1  and the second disconnect position DP 2 . 
     As shown in  FIGS. 1C, 1F, 2C, and 2F , the shifting system  18  may further include a third shift drum  80  operatively connected to the shifting assembly  32  and configured to selectively transmit torque through the shifting assembly  32 . The shifting system  18  may further include a third actuator  82  directly coupled to the shifting assembly  32  and configured to selectively transmit torque through the shifting assembly  32 . Moreover, the third shift drum  80  may define a third groove  84 , as shown in  FIG. 11C , and the second actuator  76  may be at least partially disposed in the third groove  84  of the third shift drum  80 . The third actuator  82  may be configured to selectively transmit torque through the shifting assembly  32 . 
     More specifically, in the embodiments with the third shift drum  80 , third groove  84 , and third actuator  82 , one of the second and third shift drums  74 ,  80  may be operatively connected to the disconnect  28  of the shifting assembly  32  and the other of the second and third shift drums  74 ,  80  may be operatively connected to the clutch plates  40  of the shifting assembly  32 . In other words, the second shift drum  74  may be operatively connected to the disconnect  28  of the shifting assembly  32  and the third shift drum  80  may be operatively connected to the clutch plates  40  of the shifting assembly  32 . Alternatively, the second shift drum  74  may be operatively connected to the clutch plates  40  of the shifting assembly  32  and the third shift drum  80  may be operatively connected to the disconnect  28  of the shifting assembly  32 . In the embodiments with the second and third shift drums  74 ,  80 , the clutch plates  40  and the disconnect  28  may be moved independently of one another. 
     The shifting system  18  may include an electric motor  86  coupled to the shift drum  64  to rotate the shift drum  64 . In the embodiments with first, second, and/or third shift drums  70 ,  74 ,  80 , it is to be appreciated that the shifting system  18  may have a first electric motor  88  coupled to the first shift drum  70  to rotate the first shift drum  70 , and may have a second electric motor  90  coupled to the second shift drum  74  to rotate the second shift drum  74 , and/or may have a third electric motor  92  coupled to the third shift drum  80  to rotate the third shift drum  80 . 
     A method  100  of operating the shifting system  18  is also provided. The method  100  includes the step  102  of moving the selectable one-way clutch  26  from the first clutch position X/X where the selectable one-way clutch  26  is configured to allow torque to be transmitted through one of the first and second gear ratios  14 ,  16  from the input member  20  in either the first rotational direction D 1  or the second rotational direction D 2  opposite the first rotational direction, to the second clutch position X/O where the selectable one-way clutch  26  is configured to allow torque to be transmitted through one of the first and second gear ratios  14 ,  16  from the input member  20  in the first rotational direction D 1  and prevent torque from being transmitted through one of the first and second gear ratios  14 ,  16  from the input member  20  in the second rotational direction D 2 . The step  102  of moving the selectable one-way clutch  26  from the first clutch position X/X to the second clutch position X/O is indicated by a shifting schedule in  FIG. 3 , particularly by elements A and B. 
     The method  100  also includes the step  104  of moving the plurality of clutch plates  40  from the engaged position ENG, where the clutch plates  40  are engaged with one another, to the disengaged position D-ENG, where the clutch plates  40  are disengaged from one another. The step  104  of moving the clutch plates  40  from the engaged position ENG to the disengaged position D-ENG is indicated by the shifting schedule in  FIG. 3 , particularly by element C. 
     The method  100  further includes the step  106  of moving the disconnect  28  from the first disconnect position DP 1 , where the disconnectable component  36  of the input hub  34  is disengaged from the disconnect  28 , to the second disconnect position DP 2 , where the disconnectable component  36  of the input hub  34  is engaged with the disconnect  28 . The step  106  of moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2  is indicated by the shifting schedule in  FIG. 3 , particularly by element D. 
     The method  100  further includes the step  108  of moving the selectable one-way clutch  26  from the second clutch position X/O to the third clutch position O/O where the selectable one-way clutch  26  is configured to prevent torque from being transmitted through one of the first and second gear ratios  14 ,  16  from the input member  20  in either the first rotational direction D 1  or the second rotational direction D 2  to shift the transmittance of torque from the input member  20  through one of the first and second gear ratios  14 ,  16 , to from the input member  20  through the other of the first and second gear ratios  14 ,  16 . The step  108  of moving the selectable one-way clutch  26  from the second clutch position X/O to the third clutch position O/O is indicated by the shifting schedule in  FIG. 3 , particularly by element F. 
     In one embodiment, the step  102  of moving the selectable one-way clutch  26  from the first clutch position X/X to the second clutch position X/O precedes the step  104  of moving the plurality of clutch plates  40  from the engaged position ENG to the disengaged position D-ENG. Additionally, the step  104  of moving the plurality of clutch plates  40  from the engaged position ENG to the disengaged position D-ENG may precede the step  106  of moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2 . In this way, the disconnect  28  may smoothly engage the disconnectable component  36  of the input hub  34  because the clutch plates  40  in the disengaged position D-ENG rotatably decouple the input member  20  from the output member  30 . 
     Moreover, the step  106  of moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2  may precede the step  108  of moving the selectable one-way clutch  26  from the second clutch position X/O to the third clutch position O/O. The method  100  may further include the step  110  of moving the plurality of clutch plates  40  from the disengaged position D-ENG to the engaged position ENG, as indicated by the shifting schedule in  FIG. 3 , particularly by element E. In other words, the clutch plates  40  may be re-engaged. In the embodiments where the clutch plates  40  are normally closed, the step  110  of moving the clutch plates  40  from the disengaged position D-ENG to the engaged position ENG results in the clutch plates  40  being at rest and torque being able to be transmitted through the shifting assembly  32  by the other of the first and second gear ratios  14 ,  16 . In this way, torque is allowed to be transmitted through the shifting assembly  32  to the other of the first and second gear ratios  14 ,  16 . As discussed above in step  108 , the selectable one-way clutch  26  may then move from the second clutch position X/O to the third clutch position O/O to rotatably decouple the input member  20  from the selectable one-way clutch  26  and prevent torque from being transmitted through one of the first and second gear ratios  14 ,  16 . 
     The step  106  of moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2  may precede the step  110  of moving the plurality of clutch plates  40  from the disengaged position D-ENG to the engaged position ENG. In other words, the disconnect  28  may be engaged with the disconnectable component  36  of the input hub  34  before the clutch plates  40  are re-engaged. Re-engaging the clutch plates  40  after the disconnect  28  is in the second disconnect position DP 2  smoothly rotatably couples the input member  20  and the output member  30 , thus allowing torque to be transmitted through the other of the first and second gear ratios  14 ,  16 . The shift schedule in  FIG. 3  indicated that torque is allowed to be transmitted through one of the first and second gear ratios  14 ,  16  by element A, and that torque is allowed to be transmitted through the other of the first and second gear ratios  14 ,  16  by element G. 
     It is to be appreciated that one of the first and second gear ratios  14 ,  16 , may be either the first gear ratio  14  or the second gear ratio  16 . It is also to be appreciated that the other of the first and second gear ratios  14 ,  16  may be either the first gear ratio  14  or the second gear ratio  16 . In other words, the selectable one-way clutch  26  may be configured to transmit torque through the first gear ratio  14  or may be configured to transmit torque through the second gear ratio  16 . The shifting assembly  32 , therefore, may be configured to transmit torque through the corresponding first gear ratio  14  or second gear ratio  16 . In the embodiment where the selectable one-way clutch  26  is configured to transmit torque through the first gear ratio  14 , the shifting assembly  32  is configured to transmit torque through the second gear ratio  16 . Alternatively, in the embodiment where the selectable one-way clutch is configured to transmit torque through the second gear ratio  16 , the shifting assembly  32  is configured to transmit torque through the first gear ratio  14 . It is also to be appreciated that the torque multiplication, or torque reduction, through the first gear ratio  14  may be higher than, or may be lower than, through the second gear ratio  16 . 
     A method  200  of operating the shifting system  18  for the vehicle transmission  10  includes the step  202  of engaging the clutch  25  to operatively couple one of the first and second gear ratios  14 ,  16  to the input member  20 , as indicated by elements A and B in  FIG. 3 . The method  200  also includes the step  204  of moving the disconnect  28  from the first disconnect position DP 1  where the disconnectable component  36  of the input hub  34  is disengaged from the disconnect  28 , to the second disconnect position DP 2  where the disconnectable component  36  of the input hub  34  is engaged with the disconnect  28  to operatively couple the other one of the first and second gear ratios  14 ,  16  to the input member  20  through the shifting assembly  32 . The step  204  of moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2  is indicated by element PS in  FIG. 3  and is referred to herein as “park-shifting.” 
     The steps  202 ,  204  of engaging the clutch  25  and moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2  are performed such that the clutch  25  is operatively coupled to one of the first and second gear ratios  14 ,  16  at the same time that the shifting assembly  32  is operatively coupled to the other one of the first and second gear ratios  14 ,  16 , thus preventing torque from being transmitted through either the first and second gear ratios  14 ,  16  of the vehicle transmission  10  to park the vehicle. The result of steps  202 ,  204  of engaging the clutch  25  and moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2  are indicated by element P in  FIG. 3  and is referred to herein as “park” or “parked”. 
     The method  200  may also be performed such that torque is prevented from being transmitted from either of the input member  20  or the output member  30  through either the first and second gear ratios  14 ,  16  when the clutch  25  is operatively coupled to one of the first and second gear ratios  14 ,  16  at the same time that the shifting assembly  32  is operatively coupled to the other one of the first and second gear ratios  14 ,  16 . Said differently, the method  200  may prevent torque from being transmitted from the input member  20 , through either the first and second gear ratios  14 ,  16 , to the output member  30 . Moreover, the method  200  may prevent torque from being transmitted from the output member  30 , through either of the first and second gear ratios  14 ,  16 , to the input member  20 . In this way, the method  200  may rotatably lock the input member  20  and the output member  30  relative to one another. 
     In one embodiment, the first and second gear ratios  14 ,  16  are opposing one another. Said differently, transmittance of torque through the first gear ratio  14  prevents transmittance of torque through the second gear ratio  16 , and transmittance of torque through the second gear ratio  16  prevents transmittance of torque through the first gear ratio  14 . Moreover, there may be no relative motion between the input member  20  and the output member  30  when the clutch  25  is operatively coupled to one of the first and second gear ratios  14 ,  16  at the same time that the shifting assembly  32  is operatively coupled to the other one of the first and second gear ratios  14 ,  16 . 
     The method  200  may result in there being no relative motion between the clutch  25  and the shifting assembly  32  when the clutch  25  is operatively coupled to one of the first and second gear ratios  14 ,  16  at the same time that the shifting assembly  32  is operatively coupled to the other one of the first and second gear ratios  14 ,  16 . In other words, the clutch  25  and the shifting assembly  32  may be static relative to one another throughout the duration of the vehicle being held in park. The clutch  25  is statically held as engaged, and the shifting assembly  32  is statically held such that the clutch plates  40  are in the engaged position and the disconnect  28  is in the second disconnect position DP 2 . 
     The clutch  25  may be disposed about the input member  20  and at least partially rotatably coupled to the input member  20 , as shown in  FIGS. 1A-1F . It is to be appreciated that, in the embodiments where the clutch  25  is disposed about and at least partially rotatably coupled to the input member  20 , the shifting assembly  32  may be axially aligned with either the input member  20 , as shown in  FIG. 1A-1C , or may be axially aligned with the countershaft  62 , as shown in  FIGS. 1D-1F . In the embodiments where the clutch  25  has the inner race  44  and the outer race  46 , particularly in the embodiments where the clutch  25  is the selectable one-way clutch  26 , the inner race  44  may be rotatably coupled to the input member  20 . The inner race  44  may be splined, bolted, or otherwise mechanically fixed to the input member  20  such that the inner race  44  is rotatably coupled to the input member  20 . The outer race  46 , however, may be selectively rotatably fixed to the inner race  44  through the pawl  48  or pawls  50 . 
     In the embodiments where the vehicle transmission  10  includes the countershaft  62 , the clutch  25  may be disposed about the countershaft  62  and at least partially rotatably coupled to the countershaft  62 , as shown in  FIGS. 2A-2F . It is to be appreciated that, in the embodiments where the clutch  25  is disposed about and at least partially rotatably coupled to the countershaft  62 , the shifting assembly  32  may be axially aligned with either the input member  20 , as shown in  FIGS. 2A-2C , or may be axially aligned with the countershaft  62 , as shown in  FIGS. 2D-2F . In the embodiments where the clutch  25  has the inner race  44  and the outer race  46 , particularly in the embodiments where the clutch  25  is the selectable one-way clutch  26 , the inner race  44  may be rotatably coupled to the countershaft  62 . The inner race  44  may be splined, bolted, or otherwise mechanically fixed to the countershaft  62  such that the inner race  44  is rotatably coupled to the countershaft  62 . The outer race  46 , however, may be selectively rotatably fixed to the inner race  44  through the pawl  48  or pawls  50 . 
     The disconnect  28  may be disposed about and axially aligned with the input member  20 . In this embodiment, the shifting assembly  32  may be axially aligned with the input member  20  and the input member  20  may directly transmit torque through the shifting assembly  32  without additional componentry to transmit torque from the input member  20  to the shifting assembly  32 . Moreover, the size of the vehicle transmission  10  may be reduced because the disconnect  28  is disposed about and axially aligned with the input member  20 . 
     The plurality of clutch plates  40  may be spaced axially from the disconnect  28  such that the disconnect  28  is disposed between the first gear ratio  14  and the plurality of clutch plates  40 . Although not required, the arrangement between the plurality of clutch plates  40 , the disconnect  28 , and the first gear ratio  14  results in an efficient use of space within the vehicle transmission  10  because the first gear ratio  14  and the disconnect  28  may both be partially disposed about the input member  20 , and the plurality of clutch plates  40  may be disposed near one of the first and second ends  22 ,  24  of the input member  20 . 
     The second gear ratio  16  may be spaced axially from the disconnect  28  such that the disconnect  28  is disposed between the first gear ratio  14  and the second gear ratio  16 . Although not required, the arrangement between the disconnect  28 , the first gear ratio  14 , and the second gear ratio  16  results in the disconnect  28 , as a component of the shifting assembly  32 , being able to assist in operatively coupling one of the first and second gear ratios  14 ,  16  at the same time that the clutch  25  is operatively coupled to the other of the first and second gear ratios  14 ,  16 , thus preventing torque from being transmitted through either the first and second gear ratios  14 ,  16  of the vehicle transmission  10  to park the vehicle. 
     The method  200  may also include the step  206  of moving the plurality of clutch plates from the disengaged position D-ENG where the clutch plates  40  are disengaged with one another, to the engaged position ENG where the clutch plates  40  are engaged with one another, as indicated by element C in  FIG. 3 . The step  206  of moving the plurality of clutch plates  40  from the disengaged position D-ENG to the engaged position ENG may precede the step  204  of moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2 , as indicated by element PS in  FIG. 3 . By moving the clutch plates  40  from the disengaged position D-ENG to the engaged position ENG, torque may be transmitted through the shifting assembly  32  when the disconnect  28  is in the second disconnect position DP 2 . Alternatively, it is to be appreciated that moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2  may precede the step of moving the plurality of clutch plates  40  from the disengaged position D-ENG to the engaged position ENG. By moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2  before the plurality of clutch plates  40  are moved from the disengaged position D-ENG to the engaged position ENG operatively couples the other of the first and second gear ratios  14 ,  16  through the shifting assembly  32  upon the step  206  of moving the clutch plates  40  from the disengaged position D-ENG to the engaged position ENG being accomplished. 
     It is to be appreciated that the clutch  25  used in the method  200  may be the selectable one-way clutch  26 . However, it is also to be appreciated that the clutch  25  may be any of the clutches disclosed herein, including, but not limited to, another shifting assembly as described herein, a dry friction clutch, a wet friction clutch, a single plate clutch, a multi-plate clutch, a cone clutch, a dog clutch, or a centrifugal clutch. 
     In the embodiments where the clutch  25  is the selectable one-way clutch  26 , the step  202  of engaging the clutch  25  to operatively couple one of the first and second gear ratios  14 ,  16  to the input member  20  may be further defined as a step  208  of moving the selectable one-way clutch  26  from the third clutch position O/O to the first clutch position X/X, as indicated by elements G-P in  FIG. 3 . It is to be appreciated that, in the embodiments where the clutch  25  is the selectable one-way clutch  26 , the step  202  of engaging the clutch  25  may be further defined as a step  210  moving the selectable one-way clutch  26  from the third clutch position O/O to the second clutch position X/O, and from the second clutch position X/O to the first clutch position X/X. In other words, the selectable one-way clutch  26  may be in the free/free configuration, moved to the lock/free configuration, and then moved to the lock/lock configuration. In the lock/lock configuration, one of the first and second gear ratios  14 ,  16  are operatively coupled to the selectable one-way clutch  26 . 
     In the embodiments where the clutch  25  is the selectable one-way clutch  26 , the step  210  of moving the selectable one-way clutch  26  from the third clutch position O/O to the second clutch position X/O, and from the second clutch position X/O to the first clutch position X/X may precede the step  204  of moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2 . In other words, although not required, the selectable one-way clutch  26  may be in the lock/free configuration and moved to the lock/lock position before the disconnect  28  is moved from the first disconnect position DP 1  to the second disconnect position DP 2 . In this embodiment, the selectable one-way clutch  26 , therefore, is operably coupled to one of the first and second gear ratios  14 ,  16  before the shifting assembly  32  is operably coupled to the other of the first and second gear ratios  14 ,  16 . It is to be appreciated, however, that the shifting assembly  32  may be operably coupled to one of the first and second gear ratios  14 ,  16  before the selectable one-way clutch  26  is operably coupled to the other of the first and second gear ratios  14 ,  16 . To do so, the disconnect  28  may be moved from the first disconnect position DP 1  to the second disconnect position DP 2  before the selectable one-way clutch  26  is moved from the second clutch position X/O to the first clutch position X/X. 
     It is to be appreciated that the step  206  of moving the plurality of clutch plates  40  from the disengaged position D-ENG to the engaged position ENG may precede the step  210  of moving the selectable one-way clutch  26  from the third clutch position O/O to the second clutch position X/O, and from the second clutch position X/O to the first clutch position X/X. As discussed above, the plurality of clutch plates  40  may be normally closed and at rest in the engaged position ENG. The disconnect  28 , however, may be at rest in either the first disconnect position DP 1  or the second disconnect position DP 2 . Thus, the shifting assembly  32  may be at rest when the disconnect  28  is in the first disconnect position DP 1  and the plurality of clutch plates  40  are in the engaged position ENG. 
     The shifting assembly  32 , therefore, may be placed at rest before the selectable one-way clutch  26  is moved from the second clutch position X/O to the first clutch position X/X (i.e., from the lock/free configuration to the lock/lock configuration), thus operably coupling one of the first and second gear ratios  14 ,  16  to the selectable one-way clutch  26 . With the disconnect  28  in the first disconnect position DP 1  and the selectable one-way clutch  26  in the first clutch position X/X (i.e., the lock/lock configuration), the vehicle is in either the first or second gear. 
     The vehicle may be then placed at rest such that the vehicle has no forward or backward movement. The method  200  may then be undertaken, including park-shifting through step  204  by moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2  such that the vehicle results in being parked. The disconnect  28  may be moved from the first disconnect position DP 1  to the second disconnect position DP 2  without having to move the plurality of clutch plates  40  from the engaged position ENG to the disengaged D-ENG position prior to moving disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2  because the vehicle is at rest. 
     More specifically, because no torque is being transmitted through the selectable one-way clutch  26  to one of the first and second gear ratios  14 ,  16 , the disconnect  28  may be moved from the first disconnect position DP 1  to the second disconnect position DP 2  and operably couple the other of the first and second gear ratios  14 ,  16  through the shifting assembly  32 . When both the first and second gear ratios  14 ,  16  are operably coupled to the selectable one-way clutch  26  and the shifting assembly  32 , respectively, the vehicle is parked and movement of the vehicle is prevented because torque cannot be transferred through either of the first and second gear ratios  14 ,  16 , or through both the first and second gear ratios  14 ,  16 . Said differently, the vehicle is prevented from moving when parked because the vehicle cannot be in first gear and second gear at the same time while transmitting torque through either of the first and second gear ratios  14 ,  16 . 
     A method  300  of operating the shifting system  18  for the vehicle transmission  10  is depicted by flowchart in  FIG. 10 . The method  300  includes the step  302  of disengaging the clutch to prevent torque from being transmitted through one of the first and second gear ratios  14 ,  16  from the input member  20 . The method  300  also includes the step  304  of moving the clutch plates  40  from the engaged position ENG, where the clutch plates  40  are engaged with one another, to the disengaged position D-ENG, where the clutch plates  40  are disengaged from one another. The method  300  further includes the step  306  of moving the disconnect  28  from the first disconnect position DP 1 , where the disconnectable component  36  of the input hub  34  is disengaged from the disconnect  28 , to the second disconnect position DP 2  where the disconnectable component  36  of the input hub  34  is engaged with the disconnect  28 . 
     The step  302  of disengaging the clutch may precede the step  304  of moving the clutch plates  40  from the engaged position ENG to the disengaged position D-ENG. Moreover, the step  304  of moving the clutch plates  40  from the engaged position ENG to the disengaged position D-ENG may precede the step  306  from the first disconnect position DP 1  to the second disconnect position DP 2 . The method may further include the step  308  of moving the clutch plates  40  from the engaged position ENG to the disengaged position D-ENG after the step  306  of moving the disconnect  28  from the first disconnect position DP 1  to the second disconnect position DP 2 . 
     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. Many modifications and variations of the present invention are possible in light of the above teachings, and the invention may be practiced otherwise than as specifically described.