Patent Publication Number: US-11654540-B2

Title: Powered fastener driver

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of co-pending U.S. patent application Ser. No. 17/214,002 filed on Mar. 26, 2021, which claims priority to U.S. Provisional Patent Application No. 63/000,722 filed on Mar. 27, 2020, U.S. Provisional Patent Application No. 63/042,211 filed on Jun. 22, 2020, and U.S. Provisional Patent Application No. 63/129,737 filed on Dec. 23, 2020, the entire contents of all of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to powered fastener drivers. 
     BACKGROUND OF THE INVENTION 
     There are various fastener drivers known in the art for driving fasteners (e.g., nails, tacks, staples, etc.) into a workpiece. These fastener drivers operate utilizing various means known in the art (e.g. compressed air generated by an air compressor, electrical energy, a flywheel mechanism, etc.), but often these designs are met with power, size, and cost constraints. 
     SUMMARY OF THE INVENTION 
     The present invention provides, in one aspect, a fastener driver including a housing, a cylinder supported by the housing, and a moveable piston positioned within the cylinder. A driver blade is attached to the piston and movable therewith between a top-dead-center (TDC) position and a driven or bottom-dead-center (BDC) position. The driver blade includes a body portion extending along a longitudinal axis, and a tip portion configured to contact a fastener. The tip portion is bisected by a central axis that is parallel with the longitudinal axis such that the tip portion is laterally offset relative to the body portion. 
     In some embodiments, the powered fastener driver further includes a lifter operable to move the driver blade from the BDC position toward the TDC position. A transmission is provided for providing torque to the lifter. 
     The present invention provides, in another aspect, a fastener driver including a housing, a cylinder supported by the housing, and a moveable piston positioned within the cylinder. A driver blade is attached to the piston and movable therewith between a top-dead-center (TDC) position and a bottom-dead-center (BDC) position. The driver blade includes a body portion extending along a longitudinal axis. The body portion has a first side and a second side opposite the first side. The body portion has a first width defined between the first and second sides, a plurality of teeth extending from the first side of the body, and a tip portion configured to contact a fastener. The tip portion has a second width that is less than the first width. The tip portion is bisected by a central axis that is parallel with the longitudinal axis such that the tip portion is laterally offset relative to the body portion. 
     The present invention provides, in another aspect, a fastener driver including a housing, a cylinder supported by the housing, and a moveable piston positioned within the cylinder. A driver blade is attached to the piston and movable therewith between a top-dead-center (TDC) position and a driven or bottom-dead-center (BDC) position. The driver blade includes a body portion extending along a longitudinal axis. A nosepiece is supported by the housing. The nosepiece defines a firing channel extending along the longitudinal axis. The firing channel is configured to receive the driver blade. A workpiece contact element is movably supported by the nosepiece. The workpiece contact element includes one of a plurality of recesses or a plurality of protrusions. The workpiece contact element is movable along the longitudinal axis between a first position and a second position. An endcap is removably coupled to an end portion of the workpiece contact element. The endcap is configured to contact a workpiece for moving the workpiece contact element from the first position to the second position. The endcap includes a body having the other of the plurality of recesses or the plurality of protrusions positioned on lateral sides of the body. The protrusions are engageable with the recesses for securing the endcap to the workpiece contact element. The body is formed from a plurality of different materials. 
     In some embodiments, the body of the endcap includes an interior portion and an exterior portion surrounding the interior portion. The interior portion is formed from a first material. The exterior portion is formed from a second material. The first material has a hardness that is greater than a hardness of the second material. In further other embodiments, at least a portion of the workpiece contact element also defines the firing channel. 
     The present invention provides, in another aspect, a fastener driver including a housing, a cylinder supported by the housing, and a moveable piston positioned within the cylinder. A driver blade is attached to the piston and movable therewith between a top-dead-center (TDC) position and a bottom-dead-center (BDC) position. The driver blade include a body portion extending along a longitudinal axis. A nosepiece is supported by the housing. The nosepiece defines a firing channel extending along the longitudinal axis. The firing channel is configured to receive the driver blade. A workpiece contact element is movably supported by the nosepiece. The workpiece contact element includes an end portion having first and second recesses or first and second protrusions. The workpiece contact element is movable along the longitudinal axis between a first position and a second position. An endcap is removably coupled to the end portion of the workpiece contact element. The endcap is configured to contact a workpiece for moving the workpiece contact element from the first position to the second position. The end cap includes a body having the other of the first and second recesses or the first and second protrusions positioned on lateral sides of the body. The first and second protrusions are engageable with the respective first and second recesses for securing the endcap to the workpiece contact element. The body includes an interior portion and an exterior portion surrounding the interior portion. The interior portion is formed from a first material and the exterior portion is formed from a second material. The first material has a hardness that is greater than a hardness of the second material. 
     The present invention provides, in another aspect, a fastener driver including a cylinder, a moveable piston positioned within the cylinder, and a driver blade attached to the piston and movable therewith between a top-dead-center (TDC) position and a bottom-dead-center (BDC) position. The driver blade defines a driving axis. The driver blade includes a body having a first side and an opposite, second side with the driving axis passing therebetween. A plurality of teeth extend from the first side of the body. A plurality of projections extend from the second side of the body. The body and the projections are bisected by a common plane. A lifter is operable to move the driver blade from the BDC position toward the TDC position. The lifter is configured to engage with the teeth of the driver blade when moving the driver blade from the BDC position to the TDC position. The teeth extend at an oblique angle from the first side of the body relative to the common plane. 
     The present invention provides, in another aspect, a fastener driver including a magazine configured to receive fasteners, and a nosepiece including a fastener driving channel from which consecutive fasteners from the magazine are driven. A workpiece contact element is movable relative to the nosepiece between an extended position and a retracted position. A portion of the workpiece contact element is slidably positioned within the fastener driving channel. The portion of the workpiece contact element has an aperture extending therethrough in which the fasteners pass from the magazine through the aperture into the fastener driving channel of the nosepiece to be fired. The portion of the workpiece contact element further includes a guide assembly positioned thereon. The guide assembly is configured to guide the fastener along the portion of the workpiece contact element within the fastener driving channel as the fastener is being fired into a workpiece. 
     The present invention provides, in another aspect, a fastener driver including a housing, a cylinder supported by the housing, and a moveable piston positioned within the cylinder. A driver blade is attached to the piston and movable therewith between a top-dead-center (TDC) position and a bottom-dead-center (BDC) position. The driver blade includes a body portion extending along a longitudinal axis. The body portion has a first side and an opposite, second side with the longitudinal axis extending therebetween. The driver blade also includes a plurality of teeth extending from the first side of the body portion, and a tip portion configured to contact a fastener. A lifter is operable to move the driver blade from the BDC position toward the TDC position. The lifter is configured to engage with the teeth of the driver blade when moving the driver blade from the BDC position to the TDC position. A transmission is provided for providing torque to the lifter. The body portion is bisected by a common plane containing the longitudinal axis. The teeth extend at an oblique angle from the first side of the body portion relative to the common plane. The tip portion is bisected by a central axis that is parallel with the longitudinal axis such that the tip portion is laterally offset relative to the body portion. 
     The present invention provides, in yet another aspect, a fastener driver including a housing, a cylinder supported by the housing, and a moveable piston positioned within the cylinder. A driver blade is attached to the piston and movable therewith between a top-dead-center (TDC) position and a driven or bottom-dead-center (BDC) position. The driver blade defines a driving axis. The driver blade includes a body having a first side and an opposite, second side with the driving axis passing therebetween. A plurality of teeth extends from the first side of the body. A plurality of projections extends from the second side of the body. A lifter is operable to move the driver blade from the BDC position toward the TDC position. The lifter is configured to engage with the teeth of the driver blade when moving the driver blade from the BDC position to the TDC position. A motor and a transmission operatively coupled to the motor is provided for providing torque to the lifter. A latch assembly is movable between a latched state in which the driver blade is held in an intermediate position against a biasing force of compressed gas, and a released state in which the driver blade is permitted to be driven by the biasing force toward the BDC position. The latch assembly includes a latch configured to engage with the projections, and a solenoid for moving the latch out of engagement with the driver blade when transitioning from the latched state to the released state. A magazine is configured to receive fasteners. A nosepiece includes a fastener driving channel from which consecutive fasteners from the magazine are driven. The nosepiece includes a first surface and a second surface opposite the first surface. The first surface at least partially defines the fastener driving channel. The second surface is coupled to the magazine. The fastener driver is divided by the driving axis into a first side and a second side. The lifter, the motor, and the transmission are located on the first side. The magazine is located on the second side. The solenoid is located on the second side. The solenoid defines a solenoid axis extending in a direction along the driving axis and behind the second surface of the nosepiece. 
     In some embodiments, the fastener driver further includes a frame positioned within the housing and coupled to the cylinder. The nosepiece is supported by the frame. The frame includes a solenoid support portion located on the second side of the fastener driver. The solenoid support portion is configured to support the solenoid. 
     The present invention provides, in still yet another aspect, a fastener driver including a cylinder, a moveable piston positioned within the cylinder, and a driver blade attached to the piston and movable therewith between a top-dead-center (TDC) position and a driven or bottom-dead-center (BDC) position. The driver blade defines a driving axis. A lifter is operable to move the driver blade from the BDC position toward the TDC position. A motor and a transmission operatively coupled to the motor is provided for providing torque to the lifter. The transmission is a multi-stage planetary transmission having at least a first stage and a last stage. An output shaft of the last stage extends to the lifter. A one-way clutch mechanism is configured to permit a transfer of torque to the output shaft in a first rotational direction, and prevent the motor from being driven in a second rotational direction opposite the first rotational direction. The one-way clutch is further configured to permit selective limited rotation of the output shaft in the second rotational direction. 
     The present invention provides, in another aspect, a fastener driver including a cylinder, a moveable piston positioned within the cylinder, and a driver blade attached to the piston and movable therewith between a top-dead-center (TDC) position and a driven or bottom-dead-center (BDC) position. The driver blade defines a driving axis. The driver blade includes a body having a first side and an opposite, second side with the driving axis passing therebetween. A plurality of teeth extends from the first side of the body. A plurality of projections extends from the second side of the body. A lifter is operable to move the driver blade from the BDC position toward the TDC position. The lifter is configured to engage with the teeth of the driver blade when moving the driver blade from the BDC position to the TDC position. A latch assembly is movable between a latched state in which the driver blade is held in an intermediate position against a biasing force of compressed gas, and a released state in which the driver blade is permitted to be driven by the biasing force toward the BDC position. The latch assembly includes a latch pivotable about a pivot axis toward and away from the projections. The pivot axis extends perpendicular to the driving axis. The latch assembly further includes a solenoid for pivoting the latch about the pivot axis. In the released state, the latch is divided by a latch axis, which extends parallel with the driving axis and perpendicular to the pivot axis, into a first side and a second side. The first side is located laterally closer to the driving axis than the second side. The latch includes a projection located on the second side such that the latch is weighted to pivot the latch away from the projections and toward the released state of the latch assembly. 
     The present invention provides, in yet another aspect, a fastener driver including a cylinder, a moveable piston positioned within the cylinder, and a driver blade attached to the piston and movable therewith between a top-dead-center (TDC) position and a driven or bottom-dead-center (BDC) position. The driver blade defines a driving axis. A lifter is operable to move the driver blade from the BDC position toward the TDC position. A motor and a transmission operatively coupled to the motor is provided for providing torque to the lifter. A magazine is configured to receive fasteners. The magazine includes a first end and a second end opposite the first end, and a first side and a second side spaced from the first side. The first and second sides extend between the first and second ends. A pusher is slidably coupled to the magazine. A nosepiece is coupled to the first end of the magazine. The nosepiece is configured to slidably support the driver blade. A workpiece contact element is movable with respect to the nosepiece. A blocking member is pivotally coupled to the nosepiece. The blocking member is biased toward a first position. The pusher moves the blocking member to a second position where the blocking member blocks movement of the workpiece contact element when a predetermined number of fasteners remain in the magazine. The first side of the magazine is in facing relationship with the motor and the transmission. The blocking member extends from the nosepiece on the first side of the magazine. 
     The present invention provides, in yet another aspect, a fastener driver including a magazine configured to receive fasteners, and a nosepiece including a fastener driving channel from which consecutive fasteners from the magazine are driven. The magazine extends between a first end and a second end opposite the first end. The nosepiece is coupled to the first end. The magazine includes a guide member positioned within the magazine. The guide member has an end positioned proximate the second end of the magazine. The guide member is movable between a first position in which the end of the guide member is spaced away from an internal surface of the magazine, and a second position in which the end of the guide member is moved toward the internal surface. The magazine further includes a biasing member biasing the guide member toward the first position. The guide member is selectively movable from the first position toward the second position based on a length the fasteners. 
     The present invention provides, in another aspect, a fastener driver including a cylinder, a moveable piston positioned within the cylinder, and a driver blade attached to the piston and movable therewith between a top-dead-center position and a bottom-dead-center position. The driver blade defining a driving axis. The driver blade including a body having a first side and an opposite, second side with the driving axis passing therebetween, a plurality of teeth extending from the first side of the body, and a plurality of projections extending from the second side of the body, wherein the body and the projections are bisected by a common plane. A lifter operable to move the driver blade from the bottom-dead-center position toward the top-dead-center position, the lifter configured to engage with the teeth of the driver blade when moving the driver blade from the bottom-dead-center position to the top-dead-center position. The teeth extend at an oblique angle from the first side of the body relative to the common plane. 
     The present invention provides, in another aspect, a fastener driver including a cylinder, a moveable piston positioned within the cylinder, the piston including a first opening, and a driver blade attached to the piston and movable therewith between a top-dead-center position and a bottom-dead-center position, the driver blade includes a second opening aligned with the first opening of the piston. The driver blade defining a driving axis. The driver blade including a body having a first side and an opposite, second side with the driving axis passing therebetween, a plurality of teeth extending from the first side of the body, and a plurality of projections extending from the second side of the body. The body and the projections are bisected by a common plane, and the teeth extend at an oblique angle from the first side of the body relative to the common plane. A lifter operable to move the driver blade from the bottom-dead-center position toward the top-dead-center position, the lifter configured to engage with the teeth of the driver blade when moving the driver blade from the bottom-dead-center position to the top-dead-center position. A pin extending through the aligned first and second openings for coupling the piston and the driver blade together. 
     The present invention provides, in another aspect, a fastener driver including a housing, a cylinder supported by the housing, a moveable piston positioned within the cylinder, the piston including a first opening, a driver blade attached to the piston and movable therewith between a top-dead-center position and a bottom-dead-center position. The driver blade includes a second opening aligned with the first opening of the piston. The driver blade including a body portion extending along a longitudinal axis, the body portion having a first side and an opposite, second side with the longitudinal axis extending therebetween, a plurality of teeth extending from the first side of the body portion, and a tip portion configured to contact a fastener. The tip portion bisected by a central axis that is parallel with the longitudinal axis such that the tip portion is laterally offset relative to the body portion. A lifter operable to move the driver blade from the bottom-dead-center position toward the top-dead-center position, the lifter configured to engage with the teeth of the driver blade when moving the driver blade from the bottom-dead-center position to the top-dead-center position. A pin extending through the aligned first and second openings in the piston and the driver blade for coupling the piston and the driver blade together. 
     Other features and aspects of the invention will become apparent by consideration of the following detailed description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1 A  is a side view of a powered fastener driver in accordance with an embodiment of the invention. 
         FIG.  1 B  is another side view of the powered fastener driver of  FIG.  1   , with portions of a housing of the powered fastener driver of  FIG.  1    removed. 
         FIG.  2    is a cross-sectional view of the powered fastener driver of  FIG.  1   . 
         FIG.  3    is a perspective view of the powered fastener driver of  FIG.  1   , with portions removed for clarity. 
         FIG.  4    is a front perspective view of a driver blade of the powered fastener driver of  FIG.  1   . 
         FIG.  5    is a front view of the driver blade of  FIG.  4   . 
         FIG.  6    is an enlarged, front view of a portion of a prior art driver blade. 
         FIG.  7    is an enlarged, front view of a portion of the driver blade of  FIG.  5   . 
         FIGS.  8 A- 8 C  are front views of the powered fastener driver of  FIG.  1   , illustrating a reaction force applied to the fastener driver during a fastener driving operation. 
         FIG.  9    is an enlarged view of the powered fastener driver of  FIG.  1   , with portions removed for clarity, illustrating a fastener received in a firing channel and a workpiece contact element within the firing channel. 
         FIG.  10    is a bottom view of the driver blade of  FIG.  4   . 
         FIG.  11    is an enlarged, front view of an alternative driver blade than the driver blade of  FIG.  4   . 
         FIG.  12    is a perspective view of an end portion of an alternative workpiece contact element, illustrating an endcap coupled to an end of the workpiece contact element. 
         FIG.  13    is a cross-sectional view of the end portion of the workpiece contact element of  FIG.  12   . 
         FIG.  14    is a perspective view of the endcap of  FIG.  12   . 
         FIG.  15    is a side view of a portion of the powered fastener driver of  FIG.  1 A  illustrating the frame of  FIG.  1 B  coupled between the inner cylinder of  FIG.  2    and a nosepiece, and the lifter assembly, the motor, and the transmission of  FIG.  1 B . 
         FIG.  16    is a side perspective view of the frame of  FIG.  15   . 
         FIG.  17    is another side view of the powered fastener driver of  FIG.  1 A , schematically illustrating wires extending through a housing of the powered fastener driver of  FIG.  1 A . 
         FIG.  18 A  is a side cross-sectional view of the motor, transmission, and lifter assembly of the powered fastener driver of  FIG.  15   , illustrating a planetary transmission and a one-way clutch mechanism incorporated with the planetary transmission. 
         FIG.  18 B  is an enlarged view of the transmission of  FIG.  18 A , illustrating a torque-limiting clutch mechanism incorporated with the planetary transmission. 
         FIG.  19    is a plan view of an alternative one-way clutch mechanism that may be incorporated with the planetary transmission of  FIG.  18 A . 
         FIG.  20    is an enlarged view of a portion of the one-way clutch mechanism of  FIG.  19   , illustrating the one-way clutch mechanism. 
         FIG.  21    is another enlarged view of the one-way clutch mechanism of  FIG.  20   , illustrating the one-way clutch mechanism in a completely engaged state. 
         FIG.  22    is a perspective view of the piston of the powered fastener driver of  FIG.  2   , and a driver blade coupled to the piston. 
         FIG.  23    is a front view of the piston and the driver blade of  FIG.  22   . 
         FIG.  24    is a bottom view of the piston and the driver blade of  FIG.  22   . 
         FIG.  25    is a side view of a portion of the nosepiece of  FIG.  15    coupled to a front end of a magazine, the magazine including a pusher assembly slidably coupled to the magazine. 
         FIG.  26    is a front view of the nosepiece of  FIG.  25   . 
         FIG.  27    is a side perspective view of the powered fastener driver of  FIG.  15    further including the magazine of  FIG.  25    coupled to a portion of the nosepiece, illustrating a latch assembly located on one side of the fastener driver. 
         FIG.  28    is a partial front view of a portion of the powered fastener driver of  FIG.  27   , illustrating the latch assembly in a released position relative to the driver blade. 
         FIG.  29 A  is a side cross-sectional view of the nosepiece of  FIG.  15   , illustrating a guide assembly and a fastener at a first location within the nosepiece. 
         FIG.  29 B  is another side cross-sectional view of the nosepiece of  FIG.  29 A , illustrating the fastener at a second location within the nosepiece. 
         FIG.  30    is a cutaway perspective side view of the nosepiece and the magazine of  FIG.  25   , illustrating a depth of drive adjustment mechanism of the powered fastener driver of  FIG.  1 A . 
         FIG.  31    is another cutaway perspective side view of the nosepiece and the magazine of  FIG.  25   , with the depth of drive adjustment mechanism of  FIG.  30    removed. 
         FIG.  32    is yet another cutaway perspective side view of the nosepiece and the magazine of  FIG.  25   , with the depth of drive adjustment mechanism of  FIG.  30    removed, and further illustrating a dry-fire lockout mechanism. 
         FIG.  33 A  is a cutaway perspective top view of the nosepiece and the magazine of  FIG.  25   , illustrating the dry-fire lockout mechanism of  FIG.  32    in a first position. 
         FIG.  33 B  is another cutaway perspective top view of the nosepiece and the magazine of  FIG.  33 A , illustrating the dry-fire lockout mechanism in a second position. 
         FIG.  34    is a perspective view of another driver blade of the powered fastener driver of  FIG.  22    embodying the invention. 
         FIG.  35    is a bottom view of another nosepiece embodying the invention, and the driver blade of  FIG.  34    slidably received within the nosepiece. 
         FIG.  36    is a rear perspective view of a cover portion of the nosepiece of  FIG.  35   . 
         FIG.  37    is a perspective view of the magazine of  FIG.  25   , illustrating a first body portion coupled to a second body portion. 
         FIG.  38    is a bottom perspective view of the magazine of  FIG.  37   , illustrating a guide member movably supported by the second body portion. 
         FIG.  39    is a cross-sectional view of the magazine of the powered fastener driver of  FIG.  1 A . 
         FIG.  40    is a front cross-sectional view of a portion of the magazine of  FIG.  38   . 
         FIG.  41    is a rear view of an end portion of the magazine of  FIG.  38    with the guide member of  FIG.  38    removed. 
         FIG.  42    is a side cross-sectional view of a portion of the magazine of  FIG.  38   . 
     
    
    
     Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. 
     DETAILED DESCRIPTION 
     With reference to  FIGS.  1 A- 3   , powered fastener driver  10  is operable to drive fasteners (e.g., nails, tacks, staples, etc.) held within a magazine  14  into a workpiece. The fastener driver  10  includes an inner cylinder  18  and a moveable piston  22  positioned within the cylinder  18  ( FIG.  2   ). The fastener driver  10  further includes a driver blade  26  that is attached to the piston  22  and moveable therewith. The fastener driver  10  does not require an external source of air pressure, but rather includes an outer storage chamber cylinder  30  of pressurized gas in fluid communication with the inner cylinder  18 . In the illustrated embodiment, the inner cylinder  18  and moveable piston  22  are positioned within the storage chamber cylinder  30 . With reference to  FIG.  1 B , the driver  10  further includes a fill valve  34  coupled to the storage chamber cylinder  30 . When connected with a source of compressed gas, the fill valve  34  permits the storage chamber cylinder  30  to be refilled with compressed gas if any prior leakage has occurred. The fill valve  34  may be configured as a Schrader valve, for example. 
     With reference to  FIGS.  1 A- 1 B , the fastener driver  10  includes a housing  38  having a cylinder housing portion  42  and a motor housing portion  46  extending therefrom. The cylinder housing portion  42  is configured to support the cylinders  18 ,  30 , whereas the motor housing portion  46  is configured to support a motor  50  and a transmission  54  operatively coupled to the motor  50 . The illustrated transmission  54  is configured as a planetary transmission having three planetary stages. In alternative embodiments, the transmission  54  may be a single-stage planetary transmission, or a multi-stage planetary transmission including any number of planetary stages. 
     The housing  38  further includes a handle portion  58  extending from the cylinder housing portion  42 , and a battery attachment portion  62  coupled to an opposite end of the handle portion  58 . A battery  66  ( FIG.  1 A ) is electrically connectable to the motor  50  for supplying electrical power to the motor  50 . The handle portion  58  supports a trigger  70 , which is depressed by a user to initiate a firing cycle of the fastener driver  10 . 
     With reference to  FIG.  2   , the inner cylinder  18  and the driver blade  26  define a longitudinal (or “driving”) axis  74 . During a firing cycle, the driver blade  26  and piston  22  are moveable between a top-dead-center (TDC) position and a driven or bottom-dead-center (BDC) position. The fastener driver  10  further includes a lifting assembly  78  ( FIG.  3   ), which is powered by the motor  50 , and which is operable to move the driver blade  26  from the BDC position toward the TDC position. 
     In operation, the lifting assembly  78  drives the piston  22  and the driver blade  26  toward the TDC position by energizing the motor  50 . As the piston  22  and the driver blade  26  are driven toward the TDC position, the gas above the piston  22  is compressed. Prior to reaching the TDC position, the motor  50  is deactivated and the piston  22  and the driver blade  26  are held in a ready position, which is located between the TDC and the BDC positions. Upon user depression of the trigger  70  ( FIG.  1 A ), the lifter assembly  78  continues lifting of the driver blade  26  from the ready position to the TDC position where the driver blade  26  is released from the lifter assembly  78 . When released, the compressed gas above the piston  22  and within the storage chamber cylinder  30  drives the piston  22  and the driver blade  26  to the BDC position, thereby driving a fastener into the workpiece. The illustrated fastener driver  10  therefore operates on a gas spring principle utilizing the lifting assembly  78  and the piston  22  to compress the gas within the inner cylinder  18  and the storage chamber cylinder  30 . Further detail regarding the structure and operation of the fastener driver  10  is provided below. 
     With reference to  FIG.  3   , the lifter  82 , which is a component of the lifting assembly  78 , is coupled for co-rotation with an output shaft  422  ( FIGS.  18 A- 18 B ) of the transmission  54 . The lifter  82  includes a hub  86 . An end of the transmission output shaft  422  is rotatably secured to the hub  86 . The illustrated hub  86  is formed by two plates  90 ,  94  ( FIG.  1 B ), and includes multiple drive pins  98  ( FIG.  9   ) extending between the plates  90 ,  94 . The lifter  82  further includes roller bushings  102  positioned on each of the drive pins  98 . The roller bushings  102  are configured to facilitate rolling motion between the driver pins  98  and the driver blade  26  when raising the driver blade  26  from the BDC position to the ready position. This may reduce wear on the driver blade  26  (i.e., teeth) and/or the lifter  82 , which may increase the life of the driver  10 . The illustrated lifter  82  includes six drive pins  98 ; however, in other embodiments, the lifter  82  may include three or more drive pins  98 . The drive pins  98  and roller bushings  102  are sequentially engageable with the driver blade  26  to raise the driver blade  26  from the BDC position to the ready position. 
     With continued reference to  FIG.  3   , the driver  10  further includes a latch assembly  106  having a pawl or latch  110  for selectively holding the driver blade  26 , and a solenoid  114  for releasing the latch  110  from the driver blade  26 . The latch assembly  106  is moveable between a latched state in which the driver blade  26  is held in an intermediate position located between the BDC position and the ready position against a biasing force (i.e., the pressurized gas in the storage chamber cylinder  30 ), and a released state in which the driver blade  26  is permitted to be driven by the pressurized gas in the storage chamber cylinder  30  from the ready position toward the BDC or driven position. The latch  110  is moveable between a latched position (coinciding with the latched state of the latch assembly  106 ) in which the latch  110  is engaged with one of a plurality of projections  188  on the driver blade  26  for holding the driver blade  26  in the ready position against the biasing force of the compressed gas, and a released position (coinciding with the released state of the latch assembly  106 ) in which the driver blade  26  is permitted to be driven by the biasing force of the compressed gas from the ready position to the BDC position. 
     With continued reference to  FIG.  3   , the driver  10  further includes a nosepiece  118  positioned at a front end  630  ( FIG.  25   ) of the magazine  14 . The nosepiece  118  defines a firing channel  122  (or “fastener driving channel”) (only a portion of which is shown in  FIG.  9   ) in communication with a fastener channel  642  ( FIG.  26   ) in the magazine  14 . The firing channel  122  is configured to consecutively receive fasteners from a collated fastener strip within the fastener channel of the magazine  14 . The firing channel  122  includes a firing axis  124  that is aligned with the longitudinal axis  74 . 
     With reference to  FIGS.  1 B and  9   , the driver  10  further includes a depth of drive adjustment mechanism  130  including a workpiece contact element  134 , the protruding length of which relative to the distal end of the nosepiece  118  is adjustable to vary the depth to which a fastener is driven in to a workpiece. The workpiece contact element  134  includes an end  146  configured to engage a workpiece, as described above. 
     The workpiece contact element  134  is movable relative to the nosepiece  118  between an extended position and a retracted position. A spring (not shown) is configured to bias the workpiece contact element  134  toward the extended position. The workpiece contact element  134  is configured to be moved from the extended position toward the retracted position when the workpiece contact element  134  is pressed against a workpiece. 
     With reference to  FIGS.  4 ,  5 , and  7   , the driver blade  26  extends between a first end  164  and a second end  168  along the longitudinal axis  74 . The first end  164  is coupled to the piston  22  (e.g., by a threaded connection, a pinned connection, or the like), and the second end  168  is configured to contact a fastener  172  ( FIG.  9   ) during a firing cycle. In the illustrated embodiment, the driver blade  26  includes an elongated body  156  having a body portion  160  connected to the piston  22  (at the first end  164 ) and a tip portion  176  adjacent the second end  168 . The body portion  160  narrows or tapers toward the tip portion  176  ( FIG.  7   ). Accordingly, the body portion  160  of the driver blade  26  has a first width W 1 , and the tip portion  176  has a second width W 2  that is less than the first width W 1 . 
     With reference to  FIGS.  9  and  10   , the illustrated driver blade  26  includes a slot  177  extending along the longitudinal axis  74 . The slot  177  is configured to receive a rib  178  ( FIG.  9   ) extending from the nosepiece  118  (i.e., the base  138 ). The slot has a third width W 3  ( FIG.  10   ) corresponding to a width of the rib  178 . In the illustrated embodiment, the third width W 3  is less that W 1 , but greater than W 2 . A center of the width W 3  of the slot  177  is aligned with the longitudinal axis  74 . The slot  177  and the rib  178  are configured to facilitate movement of the driver blade  26  along the longitudinal axis  74  and inhibit movement of the driver blade  26  off-axis. (i.e., left or right from the frame of reference in  FIG.  10   .). In some embodiments, the driver blade  26  may include the rib  178  and the nosepiece  118  may include the slot  177 . 
     The driver blade  26  includes teeth  180  along the length of the body portion  160 . With particular reference to  FIG.  5   , the teeth  180  extend from a first side  184  of the driver blade  26  in a non-perpendicular direction relative to the longitudinal axis  74 . The respective roller bushings  102  are engageable with the teeth  180  when returning the driver blade  26  from the BDC position to the ready position. The illustrated driver blade  26  includes six teeth  180  such that one revolution of the lifter  82  moves the driver blade  26  from the BDC position to the ready position. Furthermore, because the roller bushings  102  are capable of rotating relative to the respective driver pins  98 , sliding movement between the roller bushings  102  and the teeth  180  is inhibited when the lifter  82  is moving the driver blade  26  from the BDC position to the ready position. As a result, friction and attendant wear on the teeth  180  that might otherwise result from sliding movement between the driver pins  98  and the teeth  180  is reduced. The driver blade  26  further includes the axially spaced projections  188  formed on a second side  190  opposite the teeth  180 . The latch  110  is engageable with one of the projections  188  when maintaining the driver blade  26  in the ready position, as discussed above. 
     With particular reference to  FIG.  7   , the tip portion  176  is offset relative to the longitudinal axis  74 , which bisects (i.e., extends along a center of) the body portion  160 . The tip portion  176  is bisected by a central axis  194  that is parallel with the longitudinal axis  74 . In other words, the tip portion  176  is positioned closer to the first side  184  of the driver blade  26  than the second side  190  of the driver blade  26 , such that the tip portion  176  is laterally offset relative to the body portion  160 , the purpose of which is described below. 
     With reference to  FIGS.  22 - 24   , the illustrated driver blade  26  is manufactured such that the body  156 , and each of the projections  188  are bisected by a common plane P 2  (e.g., a second plane) ( FIG.  24   ). The longitudinal axis  74  extends perpendicular to the plane P. 
     With particular reference to  FIG.  24   , the teeth  180  extend from the first side  184  of the body  156  in an oblique direction relative to the second plane P 2 . The teeth  180  defines a first plane P 1  that is oriented at an oblique angle A relative to the second plane P 2 . For example, the illustrated teeth  180  extend in a direction at the angle A of about 20 degrees relative to the second plane P 2 . In other embodiments, the angle A may be between about 10 degrees and 40 degrees. Still further, in other embodiments, the angle A may be between about 15 degrees and 30 degrees. Accordingly, the teeth  180  are not in the same plane P 2  as the projections  188 . The inclined or oblique direction that the teeth  180  extend may reduce an overall size of the tool  10 , thereby decreasing an overall weight of the tool  10 . 
     With reference to  FIGS.  22 - 23   , rather than a threaded connection as shown in  FIGS.  4  and  5   , the illustrated driver blade  26  is coupled to the piston  22  by a pinned connection. In the illustrated embodiment, the piston  22  includes an opening  195  that is aligned with an opening in the driver blade  26 . A pin  196  ( FIG.  23   ) extends through the opening  195  of the piston  22  and the opening of the driver blade  26  for coupling the piston  22  and the driver blade  26  together. In addition, the piston  22  defines a slot  197  configured to receive an end portion  199  of the driver blade  26 . The illustrated slot  197  extends perpendicular to the longitudinal axis  74 . The pin  196  is configured to extend through the end portion  199  of the driver blade  26  when it is received in the slot  197 . The pinned connection is configured to limit movement of the driver blade  26  relative to the piston  22  in select directions. For example, in the illustrated embodiment, the pin  196  extends through driver blade  26  along a vertical axis Z transverse to the longitudinal axis  74  (e.g., between a top and a bottom of the driver blade  26  from the frame of reference of  FIG.  22   ), and the end portion  199  extends transverse to the longitudinal axis  74  within the slot  197 . Accordingly, the pinned connection inhibits movement of the driver blade  26  relative to the piston  22  along the vertical axis Z (e.g., in a top or bottom direction from the frame of reference of  FIG.  22   ), but allows limited movement of the driver blade  26  relative to the piston  22  along a lateral axis Y (e.g., left or right direction along the second plane P from the frame of reference of  FIGS.  22  and  24   ), which is transverse to both the longitudinal axis  74  and the vertical axis Z. 
     With reference to  FIG.  9   , a fastener  172  received in the firing channel  122  of the nosepiece  118  has a shank  198  extending along a fastener axis  202 . When the fastener  172  is loaded in the firing channel  122 , the fastener axis  202  is aligned with the longitudinal axis  74 . In addition, in the illustrated embodiment, the fastener  172  is a nail including a nail head  206  positioned on one end of the shank  198 . The tip portion  176  of the driver blade  26  is configured to contact the nail head  206  as the driver blade  26  is driven from the TDC position to the BDC position. 
     With reference to  FIGS.  8 A- 8 C , prior to a fastener driving cycle, the longitudinal axis  74  of the fastener driver  10  is contained within a central plane C, which is perpendicular to an underlying workpiece. The lifting assembly  78  is positioned on one side of the plane C (e.g., to the right from the frame of reference of  FIGS.  8 A- 8 C ), and the latch assembly  106  is positioned on the opposite side of the plane C (e.g., to the left from the frame of reference of  FIGS.  8 A- 8 C ). The location of the lifting assembly  78  causes a center of mass M of the fastener driver  10  to shift such that the center of mass M is located offset from the plane C toward the lifter-side of the fastener driver  10  (e.g., to the right from the frame of reference of  FIGS.  8 A- 8 C ). When the driver blade  26  is driven from the TDC position to the BDC position, the fastener  172  in the firing channel  122  is driven along the longitudinal axis  74 , and a reaction or recoil force is applied to the fastener driver  10  in an equal and opposite direction D 1 , which is coaxial with the longitudinal axis  74  and thus contained within the plane C. The recoil force imparts a moment about the center of mass M of the fastener driver  10 , causing it to rotate (i.e., counter-clockwise from the frame of reference of  FIG.  8 C ) as the fastener  172  is driven into a workpiece. This causes the longitudinal axis  74  to tilt to an oblique angle relative to the plane C and the workpiece, thereby misaligning the longitudinal axis  74  with the plane C shortly after the driver blade  26  reaches the BDC position. 
       FIG.  6    illustrates a conventional driver blade  26 ′ having a tip portion  176 ′ that is aligned with a longitudinal axis  74 ′. When the driver blade  26 ′ is used with the fastener driver  10  having a center of mass M that is located offset from the plane C, as described above, at least a portion of the tip portion  176 ′ may contact the workpiece shortly after the driver blade  26 ′ reaches the BDC position due to the rotation of the fastener driver  10  about the center of mass M by the recoil force. More specifically, rotation of the fastener driver  10  causes a position of the driver blade  26 ′ to be shifted (e.g., laterally) relative to the nail head  206  as the fastener  172  is driven into the workpiece. As such, a portion of the tip portion  176 ′ extends past or protrudes over the nail head  206  shortly after the driver blade  26 ′ reaches the BDC position. This portion of the tip portion  176 ′ that has shifted and does not contact the nail head  206  as the driver blade  26 ′ reaches the BDC position will engage or hit the workpiece proximate the nail head  206 , thereby possibly causing damage to the workpiece. 
     As illustrated in  FIG.  7   , the central axis  194  of the tip portion  176  embodying the invention is offset from the longitudinal axis  74  a predetermined distance B. Therefore, the central axis  194  of the tip portion  176  is laterally offset from the longitudinal, firing, and fastener axes  74 ,  124 ,  202 , respectively, resulting in the tip portion  176  contacting only a portion of the nail head  206  during a fastener driving cycle. That is, a partial width of the tip portion  176  will extend past (e.g., overhang), or not otherwise contact, the nail head  206  during a fastener driving cycle. 
     The predetermined distance B is selected such that the tip portion  176  remains in contact with the nail head  206  through the conclusion of the fastener driving cycle, as well as, to account for the rotation of the fastener driver  10  about its center of mass M following the recoil force being applied to the driver  10 . In other words, the predetermined distance B is selected such that as the fastener driver  10  rotates due to the recoil force, the tip portion  176  is configured to move laterally relative to the nail head  206  such that the central axis  194  of the tip portion  176  is moved closer toward the fastener axis  202  of the fastener  172  being driven. Accordingly, no portion of the tip portion  176  is configured to contact or otherwise engage the workpiece shortly after the driver blade  26  reaches the BDC position. This may inhibit or prevent damage to the workpiece by the driver blade  26  due to the rotation of the fastener driver  10  by the recoil force. 
     Furthermore, the predetermined distance B may be based on a size (e.g., length) of the fastener  172 . More specifically, the predetermined distance B for fasteners having a longer length (and therefore resulting in a larger recoil force and moment applied to the center of mass M) may be greater than the predetermined distance B for fasteners having a shorter length. 
     In operation, upon the trigger  70  being pulled to initiate a fastener driving cycle, the motor  50  is activated to rotate the lifter  82  and then the solenoid  114  is energized to pivot the latch  110  from the latched position to the release position, thereby repositioning the latch  110  so that it is no longer engageable with one of the projections  188  (defining the released state of the latch assembly  106 ). The motor  50  continues to rotate the lifter  82 , thereby displacing the driver blade  26  upward past the ready position a slight amount before a lower-most tooth  180  on the driver blade  26  slips off the respective driver pin  98 /roller bushing  102  (at the TDC position of the driver blade  26 ). Thereafter, the piston  22  and the driver blade  26  are thrust downward toward the BDC position by the expanding gas in the storage chamber cylinder  30 . As the driver blade  26  is displaced toward the BDC position, the motor  50  remains activated to continue rotation of the lifter  82 . 
     As the driver blade  26  is displaced toward the BDC position, at least a portion of the tip portion  176  of the driver blade  26  contacts the fastener  172  (e.g., nail head  206 ) within the firing channel  122 . After the fastener  172  is driven into the workpiece, the recoil force applied to the fastener driver  10  rotates the fastener driver  10  about the center of mass M as described above, thereby causing the tip portion  176  of the driver blade  26  to laterally shift relative to the nail head  206 , and the central axis  194  of the tip portion  176  is moved closer toward the fastener axis  202 . For a short duration of time after the fastener  172  is driven into the workpiece and while the driver blade  26  dwells at the BDC position, the tip portion  176  remains in contact with the fastener  172 , and no portion of the tip portion  176  extends from or overhangs past the nail head  206  of the fastener  172 . 
     Shortly after the driver blade  26  reaches the BDC position, a first of the driver pins  98 /roller bushing  102  on the lifter  82  engages one of the teeth  180  on the driver blade  26  and continued rotation of the lifter  82  raises the driver blade  26  and the piston  22  toward the ready position. Shortly thereafter and prior to the lifter  82  making one complete rotation, the solenoid  114  is de-energized, permitting the latch  110  to re-engage the driver blade  26  and ratchet around the projections  188  as upward displacement of the driver blade  26  continues (defining the latched state of the latch assembly  106 ). Continued rotation of the lifter  82  raises the driver blade  26  to the ready position, and the latch  110  engages one of the projections  188  to maintain the driver blade  26  in the ready position. 
     With reference to  FIG.  11   , in alternative embodiments, the entire driver blade  26 A within the firing channel  122  is offset (i.e., spaced from) relative to the firing axis  124  of the firing channel  122  instead of just the tip portion  176 . In other words, the driver blade  26 A (which is similar to the conventional driver blade  26 ′ of  FIG.  6   ) includes a tip portion  176 A that is centered relative to a body portion  160 A such that a central axis  194 A of the tip portion  176 A is coaxial with the longitudinal axis  74 A, but the central axis  194 A and longitudinal axis  74 A are offset relative to the firing axis  124  of the firing channel  122 . In this alternative embodiment, the fastener axis  202  of the fastener  172  remains coaxial with the firing axis  124  such that a portion of the tip portion  176  will extend past (e.g., overhang) and not be in contact with the nail head  206  while the fastener  172  is driven into the workpiece and prior to the recoil force applying a moment to the center of mass M, causing the driver  10  to rotate. Similar to the disclosed embodiment above, the central axis  194 A and longitudinal axis  74 A are offset relative to the center plane C such that the longitudinal axis  74 A moves toward the fastener axis  202  by the recoil force causing rotation of the fastener driver  10  about the center of mass M after the driver blade  26 A reaches the BDC position, thereby inhibiting or preventing any portion of the tip portion  176 A to contact or otherwise engage the workpiece when the driver blade  26 A reaches the BDC position. 
     In further alternative embodiments, a position of the fastener channel of the magazine  14  may be offset (i.e., laterally spaced) from the longitudinal axis  74 /firing axis  124  instead of the driver blade  26  including the offset tip portion  176  or the entire driver blade  26 A being offset. In other words, the longitudinal axis  74  of the driver blade  26 A is aligned with the firing axis  124 , but the fastener channel of the magazine  14  is offset such that the fastener  172  being received in the firing channel  122  is already offset relative to the firing axis  124  as the fastener  172  enters the firing channel  122 . In this alternative embodiment, a portion of the tip portion  176  will still extend past (e.g., overhang) and not be in contact with the nail head  206  while the fastener  172  is driven into the workpiece and prior to the recoil force applying a moment to the center of mass M, causing the driver  10  to rotate. Similar to the disclosed embodiment above, the fastener channel is offset relative to the center plane C and longitudinal axis  74  such that the longitudinal axis  74  moves toward the fastener axis  202  by the recoil force causing rotation of the fastener driver  10  about the center of mass M after the driver blade  26  reaches the BDC position, thereby inhibiting or preventing any portion of the tip portion  176  to contact or otherwise engage the workpiece when the driver blade  26  reaches the BDC position. 
     In addition, in this alternative embodiment, a user may be able to adjust the offset (i.e., the predetermined distance B) of the fastener channel relative to the center plane C and longitudinal axis  74  based on a size of the fastener  172 . Further, the fastener driver  10  may be configured to detect the size of the fastener  172  and automatically adjust the offset (predetermined distance B) based on the size of the fastener  172 . 
     In further alternative embodiments, both the tip portion  176  of the driver blade  26  and the fastener channel may be slightly offset to account for the rotation of the fastener driver  10  about the center of mass M by the recoil force. 
       FIGS.  12 - 14    illustrate another embodiment of a workpiece contact element  134 ′ of the powered fastener driver  10 . The workpiece contact element  134 ′ includes a tip or endcap  220  positioned on an end portion  224  of the workpiece contact element  134 ′. The end portion  224  includes an end  146 ′ ( FIG.  13   ) of the workpiece contact element  134 ′. The endcap  220  is configured to contact the workpiece when moving the workpiece contact element  134 ′ from the extended position to the retracted position. 
     The endcap  220  is removably coupled to the end portion  224  of the workpiece contact element  134 ′. In the illustrated embodiment, as shown in  FIG.  13   , the end portion  224  of the workpiece contact element  134 ′ includes first and second protrusions  228  extending therefrom. The endcap  220  includes corresponding first and second recesses  232  that receive the respective first and second protrusions  228 . Engagement between the protrusions  228  and the recesses  232  secures the endcap  220  to the workpiece contact element  134 ′. In other embodiments, the workpiece contact element  134 ′ may include the recesses and the endcap  220  may include the protrusions. In further other embodiments, the powered fastener driver  10  may include one or more protrusions  228 /recesses  232 . For example, as shown in the illustrated embodiment, the workpiece contact element  134 ′ includes third and fourth recesses  240  proximate the first and second protrusions  228 , respectively, and the endcap  220  includes corresponding third and fourth protrusions  236  proximate the first and second recesses  232 , respectively. The illustrated recesses  232  and the protrusions  236  are formed on lateral sides  241  of the endcap  220 . 
     With particular reference to  FIG.  14   , the endcap  220  includes a body  242 . The body  242  is formed by a core or interior portion  244 , and an exterior portion  248  surrounding the interior portion  244 . The body  242  is formed from different materials. In the illustrated embodiment, the interior portion  244  of the endcap  220  is formed from a first material and the exterior portion  248  is formed from a second material  248 . The first material has a hardness that is different than the second material. The interior portion  244  is in contact with and/or proximate the end portion  224  of the workpiece contact element  134 ′. Still further, in the illustrated embodiment, the interior portion  244  forms a portion of the first and second recesses  232  and a portion of the third and fourth protrusions  236 . The exterior portion  248  of the endcap  220  forms the remaining portion of the body  242  including the remaining portion of the first and second recesses  232  and the remaining portion of the third and fourth protrusions  236 . 
     In the illustrated embodiment, the first material has a hardness that is greater than a hardness of the second material. For example, the first material is hard plastic, and the second material is soft rubber. The first material is selected to prevent or inhibit the endcap  220  from decoupling (e.g., falling off) from the end portion  224  of the workpiece contact element  134 ′ during use and/or transportation of the powered fastener driver  10 . The second material is selected to prevent or inhibit damage of the workpiece by the endcap  220  during use of the powered fastener driver  10 . 
     With particular reference to  FIG.  27   , the driver  10  may be generally divided into two sides with respect to the longitudinal axis  74 . More specifically, from the frame of reference of  FIG.  27   , the side of the driver  10  on which the magazine  14  is located and substantially visible to a user is referred to as the ‘magazine side  378 ,’ and the opposite side of the driver  10  relative to the longitudinal axis  74  on which the motor  50 /lifting assembly  78  is located is referred to as the ‘motor side  382 .’ The location of different features of the driver  10  described herein may be specified as being located on the magazine side  378  or the motor side  382 . Further detail regarding the structure and operation of the fastener driver  10  is provided below. 
     With reference to  FIGS.  15 - 17   , the driver  10  further includes a frame  386  positioned within the housing  38 . The frame  386  is coupled to one end of the inner cylinder  18 . The frame  386  is formed by a plurality of portions  390 ,  394 ,  398 . The illustrated frame  386  includes a cylinder support portion  390 , a lifter housing portion  394 , and a solenoid support portion  398  ( FIG.  16   ). When assembled, the lifter housing portion  394  is positioned on the motor side  382  of the driver  10  and the solenoid support portion  398  is positioned on the magazine side  378 . The cylinder support portion  390  is coupled to the inner cylinder  18 . In the illustrated embodiment, the cylinder support portion  390  is threadably coupled to an outer surface of the inner cylinder  18  ( FIG.  2   ). The lifter housing portion  394  supports the lifting assembly  78 . The solenoid support portion  398  is configured to support the solenoid  114  of the latch assembly  106 , as further discussed below. 
     The frame  386  further includes a plurality of retaining elements  402 . Each retaining element  402  includes a projection  406  extending from the frame  386 , and a hole  410  extending through the respective projection  406 . A fastener (e.g., zip tie; not shown) is configured to extend through the hole  410  to secure at least a portion of wires  414  (shown schematically in  FIG.  17   ) to the respective retaining element  402 . In the illustrated embodiment, the frame  386  includes three retaining elements  402 . Two of the retaining elements  402  is positioned on the cylinder support portion  390 , and the remaining retaining element  402  is positioned on the lifter housing portion  394 . In addition, each of the illustrated retaining elements  402  is generally located on the motor side  382  of the driver  10 . In other embodiments, the frame  386  may include one or more retaining elements  402  positioned on any portion of the frame  386 . The retaining elements  402  are integrally formed with the frame  386 . Each retaining element  402  is configured to facilitate retaining of the wires  414  to the frame  386 . This may facilitate assembly of the tool  10  while inhibiting pinching of the wires  414  such as when the housing  38  is formed over the frame  386 . Furthermore, the retaining elements  402  may inhibit or prevent the wires  414  from getting caught up in the lifting assembly  78  during operation of the tool  10 . 
     With reference to  FIGS.  18 A- 18 B , the transmission  54  includes an input (i.e., a motor output shaft  418 ) and the output shaft  422  extending to the lifter  82 , which is operable to move the driver blade  26  from the driven position to the ready position. In other words, the transmission  54  provides torque to the lifter  82  from the motor  50 . The transmission  54  is configured as a planetary transmission having first, second, and third planetary stages  430 ,  434 ,  438 . In alternative embodiments, the transmission  54  may be a single-stage planetary transmission, or a multi-stage planetary transmission including any number of planetary stages. A transmission housing  442  houses the components of the planetary transmission  54 . The illustrated transmission housing  442  includes a first portion  446  and a second portion  450 . The transmission  54  further includes a rotational axis  454  extending through the transmission housing  442 . The motor output shaft  418  and the output shaft  422  at least partially define the rotational axis  454 . 
     With continued reference to  FIGS.  18 A- 18 B , the first planetary stage  430  includes a ring gear  458 , a carrier  462 , a sun gear  466 , and multiple planet gears  470  coupled to the carrier  462  for relative rotation therewith. The sun gear  466  is drivingly coupled to the motor output shaft  418  and is enmeshed with the planet gears  470 . The ring gear  458  includes a toothed interior peripheral portion  474 . The plurality of planet gears  470  are rotatably supported upon the carrier  462  and are engageable with (i.e., enmeshed with) the toothed interior peripheral portion  474 . 
     The second planetary stage  434  includes a ring gear  478 , a carrier  482 , and multiple planet gears  486  coupled to the carrier  482  for relative rotation therewith. The ring gear  478  includes a first toothed interior peripheral portion  490 , and a second interior peripheral portion  494  adjacent the toothed interior peripheral portion  490 . The carrier  462  of the first planetary stage  430  further includes an output pinion  498  that is enmeshed with the planet gears  486  which, in turn, are rotatably supported upon the carrier  482  of the second planetary stage  434  and enmeshed with the toothed interior peripheral portion  490  of the ring gear  478 . The ring gear  478  of the second planetary stage  434  may be selectively rotatable relative to the transmission housing  442 , as further discussed below. 
     With continued reference to  FIGS.  18 A- 18 B , the driver  10  further includes a one-way clutch mechanism  502  incorporated in the transmission  54 . More specifically, the one-way clutch mechanism  502  includes the carrier  462  of the first planetary stage  430 , and which is also a component (i.e., output pinion  498 ) in the second planetary stage  434 . The one-way clutch mechanism  502  permits a transfer of torque to the output shaft  422  of the transmission  54  in a single (i.e., first) rotational direction, yet prevents the motor  50  from being driven in a reverse direction in response to an application of torque on the output shaft  422  of the transmission  54  in an opposite, second rotational direction. In the illustrated embodiment, the one-way clutch mechanism  502  is incorporated with the first planetary stage  430  of the transmission  54 . In alternative embodiments, the one-way clutch mechanism  502  may be incorporated with the third planetary stage  438 , for example. 
     The third planetary stage  438  includes a ring gear  506 , a carrier  510 , and multiple planet gears  514  coupled to the carrier  510  for relative rotation therewith. The carrier  482  of the second planetary stage  434  further includes an output pinion  518  that is enmeshed with the planet gears  514  which, in turn, are rotatably supported upon the carrier  510  of the third planetary stage  438  and enmeshed with a toothed interior peripheral portion  522  of the ring gear  506 . The ring gear  458  of the first planetary stage  430  and the ring gear  506  of the third planetary stage  438  are fixed relative to the transmission housing  442 . The carrier  510  is coupled to the output shaft  422  for relative rotation therewith. 
     With reference to  FIG.  18 B , the driver  10  further includes a torque-limiting clutch mechanism  526  incorporated with the transmission  54 . More specifically, the torque-limiting clutch mechanism  526  includes the ring gear  478 , which is also a component of the second planetary stage  434 . The torque-limiting clutch mechanism  526  limits an amount of torque transferred to the transmission output shaft  422  and the lifter  82 . In the illustrated embodiment, the torque-limiting clutch mechanism  526  is incorporated with the second planetary stage  434  of the transmission  54 , and the one-way and torque-limiting clutch mechanisms  502 ,  526  are coaxial (i.e., aligned with the rotational axis  454 ). 
     With reference to  FIG.  18 B , the torque-limiting clutch mechanism  526  includes a plurality of detent members  530  (only one of which is shown) movably supported by the ring gear  478  of the second planetary stage  434 . The detent members  530  are engageable with respective lugs positioned on an annular front end of the second interior peripheral portion  494  of the ring gear  478  to inhibit rotation of the ring gear  478 . The torque-limiting clutch mechanism  526  further includes a plurality of springs  534  for biasing the detent members  530  toward the annular front end of the second interior peripheral portion  494  of the ring gear  478 . In the illustrated embodiment, the torque-limiting clutch mechanism  526  includes eight detent members  530  and eight respective springs  534 . In other embodiments, the torque-limiting clutch mechanism  526  may include four or more detent members  530  and four or more respective springs  534 . In response to a reaction torque applied to the transmission output shaft  422  that is above a predetermined threshold, torque from the motor  50  is diverted from the transmission output shaft  422  to the second planetary stage ring gear  478 , causing the ring gear  478  to rotate and the detent members  530  to slide over the lugs. 
       FIGS.  19 - 21    illustrate an alternative one-way clutch mechanism  538  that may be incorporated with the transmission  54  in place of the one-way clutch mechanism  502  and the torque-limiting clutch mechanism  526  described above. The one-way clutch mechanism  538  permits a transfer of torque to the output shaft  422  of the transmission  54  in a single (i.e., first) rotational direction (i.e., clockwise from the frame of reference of  FIG.  19   ), yet prevents the motor  50  from being driven in a reverse direction in response to an application of torque on the output shaft  422  of the transmission  54  in an opposite, second rotational direction (e.g., counter-clockwise from the frame of reference of  FIG.  19   ). In addition, the one-way clutch mechanism  538  allows selective limited rotation of the transmission output shaft  422  to facilitate unjamming of the driver  10 . In the illustrated embodiment, the one-way clutch mechanism  538  is incorporated with the first planetary stage  430  of the transmission  54 . In alternative embodiments, the one-way clutch mechanism  538  may be incorporated with the second or third planetary stage  434 ,  438 , for example. 
     The illustrated one-way clutch mechanism  538  includes the carrier  462 ′, which is also a component in the first planetary stage  430 ′. In addition, the one-way clutch mechanism  538  includes a plurality of ratchet members  546  ( FIG.  19   ) movably coupled to an outer periphery  550  of the carrier  462 ′. Each ratchet member  546  is pivotably coupled to the carrier  462 ′ by a pin  542 . In addition, an end  554  of each ratchet member  546  includes a surface having inclined teeth  558  complimentary of inclined teeth  562  of the toothed interior peripheral portion  474 ′ of the ring gear  458 ′ of the first planetary stage  430 ′. As such, the end  554  of each ratchet member  546  is configured as a ratcheting surface. Each ratchet member  546  ratchets relative to the toothed interior peripheral portion  474 ′ of the ring gear  458 ′ as the carrier  462 ′ rotates in the first rotational direction (e.g., clockwise from the frame of reference of  FIG.  19   ). Said another way, each ratchet member  546  is slidably engageable with the toothed interior peripheral portion  474 ′ of the ring gear  458 ′ as the carrier  462 ′ rotates in the first rotational direction. In the illustrated embodiment, the one-way clutch mechanism  538  includes six ratchet members  546 . In alternative embodiments, the one-way clutch mechanism  538  may include four or more ratchet members  546 . 
     As each end  554  the respective ratchet member  546  engages with the toothed interior peripheral portion  474 ′ of the ring gear  458 ′, a spacing  566  ( FIG.  21   ) is formed between the inclined teeth  558  of the respective ratchet member  546  and the respective teeth  562  of the toothed interior peripheral portion  474 ′. The spacing  566  is selected such that the carrier  462 ′ is allowed to rotate a limited degree of rotation about the rotational axis  454 ′ in the second, opposite rotational direction (e.g., counter-clockwise from the frame of reference of  FIG.  19   ). In particular, the limited degree of rotation is a small amount (i.e., larger than one degree but less than ten degrees). In the illustrated embodiment, the spacing  566  is selected such that the carrier  462 ′ may rotate in the second rotational direction by up to four degrees relative to the rotational axis  454 ′. In other embodiments, the carrier  462 ′ may rotate in the second rotational direction by up to six degrees. Still further, in other embodiments, the carrier  462  may rotate in the second rotational direction by up to eight degrees. As such, the spacing  566  may allow selected movement or what may be referred to as ‘backlash’ of the carrier  462 ′ relative to the ring gear  458 ′. 
     In operation of the one-way clutch mechanism  538 , the ratchet members  546  ratchet about the toothed interior peripheral portion  474 ′ of the ring gear  458 ′ as the carrier  462 ′ rotates in the first rotational direction (i.e., clockwise from the frame of reference of  FIG.  19   ). However, when the piston  22 /driver blade  26  has reached the ready position, or if rotation of the lifter  82  of the lifting assembly  78  has become jammed or otherwise the movement inhibited when the driver blade  26  is being lifted from the BDC position toward the ready position, an application of torque on the transmission output shaft  422  is applied to the carrier  462 ′ in the second rotational direction (i.e., counter-clockwise from the frame of reference of  FIG.  19   ). The spacing  566  between the inclined teeth  558  and the toothed interior peripheral portion  474 ′ of the ring gear  458 ′ allows the carrier  462 ′ to rotate a small amount (e.g., 4 degrees) in the second rotational direction until the spacing  566  is closed and the inclined teeth  558  engage with the toothed interior peripheral portion  474 ′ of the ring gear  458 ′ to thereby prevent further rotation of the carrier  462 ′ (and the transmission output shaft  422 ) in the second rotational direction. Consequently, the one-way clutch mechanism  538  prevents the transmission  54  from applying torque to the motor  50 , which might otherwise back-drive or cause the motor  50  to rotate in a reverse direction, in response to an application of torque on the transmission output shaft  422  in the opposite, second rotational direction (i.e., when the piston  22  and the driver blade  26  has reached the ready position). 
     In addition, the limited degree of rotation of the carrier  462 ′ in the second rotational direction facilitates re-alignment of the lifter  82  relative to the driver blade  26 . Accordingly, the one-way clutch mechanism  538  may be provided with backlash to facilitate unjamming of the lifting assembly  78  and the driver blade  26 . 
     With reference to  FIGS.  1 B and  25 - 27   , the nosepiece  118  is supported by the frame  386 . The nosepiece  228  includes a nosepiece base  622  and a nosepiece cover  626  coupled to the nosepiece base  622 . The nosepiece base  622  is coupled to the frame  386 . In addition, the nosepiece base  622  is positioned at the front end  630  ( FIG.  25   ) of the magazine  14 . The nosepiece cover  626  substantially covers the nosepiece base  622  ( FIG.  27   ). In the illustrated embodiment, the nosepiece cover  626  is pivotally coupled to the nosepiece base  622  by a latch mechanism  634 . 
     With reference to  FIGS.  26  and  29 A- 29 B , the nosepiece base  622  and the nosepiece cover  626  form the firing channel  122  therebetween (only a portion of which is shown in  FIG.  26   ). The magazine  14  includes the fastener channel  642  ( FIG.  26   ) along a length thereof. The firing channel  122  is in communication with the fastener channel  642 . The firing channel  122  is configured to consecutively receive fasteners from a collated fastener strip  12  ( FIG.  33 A ) stored in the fastener channel  642  of the magazine  14 . The firing channel  122  is aligned with the longitudinal axis  74  of the driver blade  26 . 
     In particular, the nosepiece base  622  includes a nail receiving aperture  646  ( FIG.  26   ), and the nosepiece cover  626  includes an elongated groove  650  ( FIG.  29 A ) in facing relationship with the nail receiving aperture  646 . Each of the aperture  646  and the elongated groove  650  extends along the longitudinal axis  74 . The nail receiving aperture  646  is partially defined by a guiding surface  654  of the nosepiece base  622 . The illustrated guiding surface  654  extends from the nosepiece base  622  toward the nosepiece cover  626  and is divided into two portions. The extended guiding surface  654  is received within the slot  177  ( FIG.  24   ) defined by a rear surface of the driver blade  26 . The nosepiece base  622  also includes an elongated slot  658  ( FIG.  26   ) located proximate the nail receiving aperture  646 , and extending on either side of the nail receiving aperture  646 . The nail receiving aperture  646  connects the fastener channel  642  of the magazine  14  to the firing channel  122  of the nosepiece  118 . 
     With reference to  FIGS.  25 - 26  and  30 - 31   , the driver  10  further includes the workpiece contact element  134  supported by the nosepiece  118  (i.e., the nosepiece base  622 ;  FIG.  25   ). The illustrated workpiece contact element  134  includes generally two portions  666 ,  670  ( FIG.  30   ), each portion  666 ,  670  formed by multiple segments, and in which adjacent segments are coupled by a bend. The first and second portions  666 ,  670  are coupled together by the depth of drive adjustment mechanism  130 , which adjusts the effective length of the workpiece contact element  134 . The first portion  666  of the workpiece contact element  134  includes an end section  678  that is slidably received in a groove  682  positioned on the magazine  14  (i.e., on a first side  734 ;  FIGS.  30  and  31   ). The end section  678  (and the groove  682 ) is positioned on the motor side  382  of the driver  10 , and below the depth of drive adjustment mechanism  130  and the nosepiece  118 , from the frame of reference of  FIG.  30   . In addition, the end section  678  forms one end of the workpiece contact element  134 . 
     Referring back to  FIGS.  26  and  29 A- 29 B , the second portion  670  of the workpiece contact element  134  includes an elongated section  686  that is slidably received within the elongated slot  658  ( FIG.  26   ) defined by the nosepiece base  622 . As such, a portion of the workpiece contact element  134  (i.e., the elongated section  686 ) at least partially defines the firing channel  122  of the nosepiece  118 . 
     The workpiece contact element  134  moves from the extended position to the retracted position when the workpiece contact element  134  contacts a workpiece and a force directed toward the workpiece is applied to the fastener driver  10 . More specifically, the end section  678  of the first portion  666  of the workpiece contact element  134  slides within the groove  682  defined by the magazine  14  ( FIG.  31   ), and the elongated section  686  of the second portion  670  slides within the slot  658  of the nosepiece base  622  ( FIG.  26   ) when the workpiece contact element  134  moves from the extended position toward the retracted position. 
     With specific reference to  FIG.  26   , the workpiece contact element  134  includes an aperture  690  extending through the elongated section  686  of the second portion  670 . The aperture  690  is aligned at least partially along its length with the nail receiving aperture  646  of the nosepiece base  622  such that the fastener channel  642  of the magazine  14  is in communication with the firing channel  122  of the nosepiece  118  through the workpiece contact element  134 . As such, each fastener passes from the magazine  14  through the nail receiving aperture  646  of the nosepiece base  622  and the aperture  690  of the workpiece contact element  134  into the firing channel  122  of the nosepiece  118 . In particular, the entire length of the aperture  690  is aligned with the nail receiving aperture  646  (and the fastener channel  642  of the magazine  14 ) when the workpiece contact element  134  is in the retracted position. 
     As shown in  FIGS.  26  and  29 A- 29 B , the nosepiece  118  further includes a first fastener guide assembly  694 . The first fastener guide assembly  694  is positioned between the nosepiece cover  626  and the nosepiece base  622 , and also between the nosepiece cover  626  and the workpiece contact element  134 . In the illustrated embodiment, the elongated section  686  of the workpiece contact element  134  includes a protrusion  696  extending therefrom. The protrusion  696  is aligned with the guiding surface  654  along the longitudinal axis  74 , and is also received in the slot  177  of the driver blade  26 . The illustrated protrusion  696  is divided into a first side portion  698  and a second side portion  702 . An end surface  706  of each of the first and second side portions  698 ,  702  is in facing relationship with the nosepiece cover  626 . The first and second side portions  698 ,  702  also at least partially define the aperture  690 . The fastener is configured to contact the end surfaces  706  of the workpiece contact element  134  as the fastener is being fired into the workpiece during a fastener-driving operation. As shown in  FIGS.  29 A- 29 B , the fastener  12 A to be fired is first guided between the guiding surface  654  of the nosepiece base  622  and the elongated groove  650  of the nosepiece cover  626 , and then is subsequently guided between the end surfaces  706  of the protrusion  696  of the workpiece contact element  134  and the elongated groove  650  of the nosepiece cover  626 . As such, the illustrated first fastener guide assembly  694  includes the elongated groove  650  of the nosepiece cover  626 , the guiding surface  654  of the nosepiece base  622 , and the end surfaces  706  of the workpiece contact element  134 . 
       FIGS.  34 - 36    illustrate an alternative driver blade  26 B and nosepiece  118 B. The nosepiece  118 B further includes a second fastener guide assembly  850  ( FIG.  35   ). The second fastener guide assembly  850  includes a plurality of guide ribs  854 ,  858  positioned within the firing channel  122 B for guiding movement of the fastener received within the firing channel  122 B along the longitudinal axis  74 B during a fastener driving operation. In the illustrated embodiment, the nosepiece cover  626 B includes a first guide rib  854  and a second guide rib  858 . Each rib  854 ,  858  extends from an inner surface  862  of the nosepiece cover  626 B toward the nosepiece base  622 B, and extends a length of the nosepiece cover  626 B relative to the longitudinal axis  74 B ( FIG.  36   ). Also, the first and second guide ribs  854 ,  858  are spaced laterally apart relative to the longitudinal axis  74 B, and the groove  650 B of the nosepiece cover  626 B is positioned between the first and the second guide ribs  854 ,  858 . As such, the fastener is positioned between the first and second guide ribs  854 ,  858  when the respective fastener is received within the firing channel  122 B. The driver blade  26 B includes a first elongated slot  866  ( FIG.  34   ) and a second elongated slot  870  configured to receive the first guide rib  854  and the second guide rib  858 , respectively. In other embodiments, the plurality of guide ribs  854 ,  858  may extend from the nosepiece base  622 B within the firing channel  122 B, and/or the second fastener guide assembly  850  may include one or more guide ribs/slots. The second fastener guide assembly  850  is configured to inhibit or prevent the fastener from moving laterally relative to the longitudinal axis  74 B (i.e., side-to-side) within the firing channel  122 B, thereby inhibiting or preventing a jam of the fastener within the nosepiece  118 B. 
     With reference to  FIG.  30   , the depth of drive adjustment assembly  130  is located on the motor side  382  of the driver  10 . The depth of drive adjustment assembly  130  includes a support member  714 , an adjustment knob  718 , and a screw portion  722 . The adjustment knob  718  is rotatably supported upon the support member  714 . The screw portion  722  extends between the first portion  666  and the second portion  670  of the workpiece contact element  134 . One end of the second portion  670  is threadably coupled to the screw portion  722 . Furthermore, the screw portion  722  is coupled for co-rotation with the adjustment knob  718 . Accordingly, the screw portion  722  and the knob  718  are rotatably supported by the support member  714 . Rotation of the adjustment knob  718  axially threads the second portion  670  along the screw portion  722  for adjusting a protruding length of the workpiece contact element  134  relative to a distal end  726  of the nosepiece  118 . More specifically, rotation of the adjustment knob  718  moves the second portion  670  relative to the first portion  670  for adjusting an effective length of the workpiece contact element  134 . As such, the adjustment knob  718  may be termed as an actuator. 
     The depth of drive adjustment assembly  130  adjusts the depth to which a fastener is driven into the workpiece. In particular, the depth of drive adjustment assembly  130  adjusts the length that the workpiece contact element  134  protrudes relative to the distal end  726  of the nosepiece  118 , thereby changing the distance between the distal end  726  of the nosepiece  118  and the workpiece contact element  134  in the extended position. In other words, the depth of drive adjustment assembly  130  adjusts how far the workpiece contact element  134  extends past the nosepiece  118  for abutting with a workpiece. The larger the gap between the distal end  726  of the nosepiece  118  and the workpiece, the shallower the depth a fastener will be driven into the workpiece. As such, the position of the workpiece contact element  134  with respect to the nosepiece  118  is adjustable to adjust the depth to which a fastener is driven. 
     With reference to  FIG.  25   , the magazine  14  is configured to receive the fasteners to be driven into the workpiece by the powered fastener driver  10 . The magazine  14  has the front end  630  and a rear end  730  opposite the front end  630 . The magazine  14  further includes the first side  734  and a second side  738  (only one of which is shown in  FIG.  25   ; see  FIG.  30   ) opposite the first side  734 , and a bottom side  742  and a top side  746  extending between the first and second sides  734 ,  738 , respectively. In particular, in the illustrated embodiment, the first side  734  is in facing relationship with the motor  50 , the transmission  54 , and the lifting assembly  78 . In addition, the second side  738  is the side of the magazine  14  that is substantially visible to a user. 
     With continued reference to  FIG.  25   , the magazine  14  further includes a pusher assembly  750  at least a portion of which is positioned within the fastener channel  642  of the magazine  14 . The pusher assembly  750  is slidably coupled to the magazine  14  and biases the collated fastener strip  12  toward the front end  630  of the magazine  14 . In particular, the magazine  14  includes a spring (not shown) configured to bias the pusher assembly  750  toward the front end  630  of the magazine  14 . As such, the pusher assembly  750  is configured to apply a constant biasing force on the fastener strip  12  toward the front end  630  of the magazine  14 . As shown in  FIGS.  33 A- 33 B , the illustrated pusher assembly  750  includes a first portion  754  and a second portion  758  movably coupled to the first portion  754  by a second spring (not shown). 
     With reference to  FIGS.  32 - 33 B , the powered fastener driver  10  further includes a dry-fire lockout assembly  766 . The dry-fire lockout assembly  766  includes the end section  678  of the first portion  666  of the workpiece contact element  134 , a blocking member  770 , and a lockout member  774  engageable with the blocking member  770 . The blocking member  770  is pivotably coupled to the nosepiece base  622  of the nosepiece  118  proximate the front end  630  of the magazine  14 . More specifically, the nosepiece base  622  includes a first side  778  having the guiding surface  654  and configured to at least partially define the firing channel  122 , and a second side  782  opposite the first side  778 . The front end  630  of the magazine  14  is secured to the second side  782 . The second side  782  further includes a support member  784  extending therefrom ( FIG.  32   ). The illustrated support member  784  is integral with the nosepiece base  622 . The support member  784  extends from the second side  782  of the nosepiece base  622  such that it is located proximate the front end  630  of the magazine  14  and on the motor side  382  of the driver  10 . 
     The blocking member  770  includes a first end portion  786  and a second, opposite end portion  790 . The first end portion  786  is pivotally coupled to the nosepiece base  622 . In particular, the first end portion  786  is pivotally coupled to the support member  784  of the nosepiece base  622  by a pin  792  ( FIG.  32   ). In the illustrated embodiment, the blocking member  770  is coupled to the nosepiece base  622  by a press fit pin connection. As such, the blocking member  770  is directly coupled to the nosepiece  118 . The second end portion  790  of the blocking member  770  is positioned proximate an end  683  ( FIG.  33 A ) of the groove  682  in the magazine  14  such that the second end portion  790  may selectively block the end  683  of the groove  682 . The illustrated blocking member  770  is configured as a pivotable lever. Accordingly, the blocking member  770  is positioned proximate the front end  630  of the magazine  14 , and on the motor side  382  of the driver  10 . In addition, the blocking member  770  is located on the first side  734  of the magazine  14 . 
     With continued reference to  FIGS.  32 - 33 B  the blocking member  770  is movable (e.g., pivotable) between a first, non-blocking or bypass position ( FIG.  33 A ), and a second, blocking position ( FIG.  33 B ). A spring (e.g., torsional spring  794 ;  FIG.  32   ) is configured to bias the blocking member  770  toward the bypass position. When the blocking member  770  is in the blocking position, the second end portion  770  of the blocking member  750  blocks the end  683  of the groove  682  where it interferes with retraction of the workpiece contact element  134 , which is a prerequisite for initiating a fastener firing cycle. More specifically, the second end portion  790  extends into a path of the end section  678  of the workpiece contact element  134  in order to prevent movement of the workpiece contact element  134  out the page from the frame of reference of  FIG.  33 B . As such, the end section  678  may be referred to as an engagement portion of the workpiece contact element  134 . 
     The lockout member  774  is movable with the second portion  758  of the pusher assembly  750 . The illustrated lockout member  774  is a side projection of the second portion  758 . The lockout member  774  is selectively engageable with the second end portion  790  of the blocking member  770  for moving the blocking member  770  from the bypass position toward the blocking position against the bias of the spring  794 . More specifically, the lockout member  774  is configured to move the blocking member  770  toward the blocking position where the blocking member  770  is configured to block movement of the workpiece contact element  134  when a predetermined number of fasteners (e.g., 0, 1, 2, etc.) remain in the magazine  14 . The predetermined number of fasteners remaining may be five or less. For example, in some embodiments, the predetermined number of fasteners may be 1, 2, 3, etc. In other embodiments, the predetermined number of fasteners may be zero. In the illustrated embodiment, the predetermined number of fasteners is five. 
     With reference to  FIGS.  27 - 28   , the driver  10  further includes the latch assembly  106  having the latch  110  and the solenoid  114 . The latch  110  is movably supported by a support portion  808  of the nosepiece base  622 . More specifically, the latch  110  is rotatable about a pivot axis  814  ( FIG.  27   ) defined by a shaft (not shown) of the latch assembly  106 . The pivot axis  814  is parallel to the rotational axis  454  of the lifter  82  ( FIG.  27   ). 
     The latch assembly  106  is positioned proximate the second side  190  of the driver blade  26 . The solenoid  114  is supported by the solenoid support portion  398  of the frame  386 . The solenoid  114  defines a solenoid axis  818  that extends at an acute angle relative to the longitudinal axis  74  ( FIG.  28   ). In particular, the solenoid support portion  398  of the frame  386  is located such that the solenoid  114  is positioned below (from the frame of reference of  FIG.  27   ) at least a portion of the nosepiece  118 , on the magazine side  378  of the driver  10 . This mounting location of the solenoid  114  may reduce an overall size of the tool  10 , thereby decreasing an overall weight of the tool  10 . Furthermore, the latch  110  is configured to rotate about the pivot axis  814  such that a tip  822  of the latch  110  is configured to engage a stop surface  826  of the nosepiece  118  ( FIG.  28   ) when the latch  110  is moved toward the driver blade  26 . 
     The solenoid  114  includes a solenoid plunger  830  ( FIG.  27   ) for moving the latch  110  out of engagement with the driver blade  26  when transitioning from the latched state to the released state. The plunger  830  includes a first end positioned within the solenoid  810  and a second end indirectly coupled to the latch  110  (i.e., via the shaft). Displacement of the plunger  830  pivots the latch  110  about the pivot axis  814  between the latched state and the released state. Energizing of the solenoid  114  displaces the plunger  830  in one direction along the solenoid axis  818 , thereby pivoting the latch  110  in a first direction (e.g., counter-clockwise). When the solenoid  114  is de-energized, an internal spring bias within the solenoid  114  causes the plunger  830  to displace in the opposite direction along the solenoid axis  818 , thereby pivoting the latch  110  in a second, opposite direction (e.g., clockwise). 
     The latch  110  is moveable between a latched position (coinciding with the latched state of the latch assembly  106 ) in which the latch  110  is engaged with one of the projections  188  on the driver blade  26 , and a released position (coinciding with the released state of the latch assembly  106 ) in which the driver blade  26  is permitted to be driven by the biasing force of the compressed gas toward to the driven position. Furthermore, the stop surface  826 , against which the latch  110  is engageable when the solenoid  114  is de-energized, limits the extent to which the latch  110  is rotatable in a clockwise direction from the frame of reference of  FIG.  28    about the pivot axis  814 . 
     With continued reference to  FIGS.  27 - 28   , the latch assembly  106  is weighted such that the latch  110  is biased (i.e., by inertial force) toward the released position. In particular, when the latch assembly  106  is in the released state, the latch  110  is divided by a latch axis  834  ( FIG.  28   ) that extends parallel with the longitudinal axis  74  and perpendicular to the pivot axis  814 . The latch axis  834  divides the latch  110  into a first side  842  and a second side  846 . The first side  842  is positioned laterally closer to the longitudinal axis  74  than the second side  846  in a radial direction relative to the longitudinal axis  74 . A projection  838  of the latch assembly  106  is located on the latch  110 , and more specifically on the second side  846  of the latch axis  834  away from the longitudinal axis  74 . The projection  838  provides additional mass on the second side  846  of the latch  110  such that a center of mass of the latch  110  is shifted or offset (i.e., to the right from the frame of reference of  FIG.  28   ). This offset weight biases the latch  110  in a clockwise direction toward the released position. In particular, the latch  110  is in the released position when the driver blade  26  is driven from the TDC position to the BDC position along a direction which is coaxial with the longitudinal axis  74 . A reaction or recoil force is applied to the fastener driver  10  in an equal and opposite direction as the direction the driver blade  26  is being driven. The bias of the latch  110  toward the released position due to the offset weight facilitates maintaining of the latch  110  away from driver blade  26  when the recoil force is applied to the driver  10 . This may inhibit or prevent the latch  110  from rotating toward the latched position, such as by the recoil force, and momentarily engaging with the driver blade  26  when the driver blade  26  is being driven from the TDC position toward the BDC position. 
       FIGS.  37 - 42    illustrate the magazine  14  or portions thereof. The magazine  14  includes a first body portion  882  and a second body portion  886  that cooperatively define the fastener channel  642  extending therethrough. The first body portion  882  is configured to receive a first portion  890  (e.g., shank) of each fastener  13  of the fastener strip  12  ( FIG.  39   ). The second body portion  886  is configured to receive a second portion  894  (e.g., head) of each fastener  13  of the fastener strip  12 . 
     With reference to  FIGS.  38 - 40   , the second body portion  886  of the magazine  14  includes a guide member  902  extending between the front end  630  and the rear end  730  of the magazine  14 . The guide member  902  is movably coupled to the second body portion  886 . The guide member  902  defines a slot  906  extending therethrough for receiving the second portions  894  of the fastener strip  12 . The guide member  902  is configured to guide the movement of the fastener strip  12  within the magazine  14 . 
     With reference to  FIGS.  41 - 42   , the driver  10  further includes a biasing member  910  positioned between an end portion  918  of the guide member  902  and an internal wall  914  of the second body portion  886  of the magazine  14 . The biasing member  910  is located proximate the rear end  730  of the magazine  14 . The biasing member  910  is configured to bias the guide member  902  toward a first position ( FIG.  40   ) in which the end portion  918  of the guide member  902  proximate the rear end  730  of the magazine  14  is positioned away from the internal wall  914  (e.g., to the left from the frame of reference of  FIG.  42   ). The guide member  902  is selectively adjustable from the first position toward a second position against the bias of the biasing member  910  in which the end portion  918  of the guide member  902  is movable (e.g., pivotable) toward the internal wall  914  (e.g., toward the right from the frame of reference of  FIG.  42   ). 
     For fasteners having a relatively shorter length, a substantial portion of the length of the subsequent fastener (e.g., half of the length) is received in the firing channel  122  at one time for being driven by the driver blade  26  into a workpiece. For fasteners  13  having a relatively longer length, a tip  922  of the first portion  890  of the subsequent fastener  13  may be received within the firing channel  122  first before the remaining portion of the first portion  890  and the respective second portion  894  (e.g., see  FIG.  39   ). When the tip  922  of the first portion  890  contacts a surface  926  of the cover portion  626  (e.g., at point  1  in  FIG.  39   ) before the remaining portion of the first portion  890  and the respective second portion  894  is received in the firing channel  122 , the biasing force of the pusher assembly  750  causes the fastener strip  12  to begin to pivot at the point of engagement between the tip  922  and the surface  926  of the cover portion  626  (e.g., in a counterclockwise direction from the frame of reference of  FIG.  39   ), thereby causing the fastener strip  12  to apply a reaction force to the guide member  902 , against the bias of the biasing member  910 . 
     When the fastener strip  12  engages at points  1 ,  2 , and  3  in  FIG.  39    (e.g., when the fastener strip  12  begins to bind within the magazine  14 ), the reaction force that the fastener strip  12  applies to the guide member  902  increases and overcomes a biasing force of the biasing member  910 , thereby moving (e.g., pivoting) the guide member  902  from the first position toward the second position. In particular, the movement of the guide member  902  toward the second position creates additional distance or clearance within the magazine  14  to allow the fastener strip  12  to shift within the magazine about a pivot point  930  proximate the nosepiece  118 . Accordingly, the movement of the guide member  902  from the first position toward the second position is configured to accommodate the fasteners  13  having the relatively longer length by selectively providing the additional clearance within the magazine  14 . In addition, the movement of the guide member  902  from the first position toward the second position may allow the fasteners having a relatively longer length to be more substantially aligned with the firing channel  122  before being driven by the driver blade  26 , thereby inhibiting misfiring. Accordingly, the guide member  902  is maintained in the first position by the biasing member  910 , and selectively movable toward the second position based on the length of the fasteners  13  of the fastener strip  12 . 
     Although the invention has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of one or more independent aspects of the invention as described. 
     Various features of the invention are set forth in the following claims.