Patent Publication Number: US-2023146406-A1

Title: Latch assembly

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/085,497, filed Sep. 14, 2018, which is a National Stage Application of PCT/US2017/022282, filed Mar. 14, 2017, which claims the benefit of U.S. Provisional Application No. 62/308,932, filed Mar. 16, 2016 which applications are incorporated herein by reference. To the extend appropriate, a claim of priority is made to each of the above disclosed applications. 
    
    
     TECHNICAL FIELD 
     This disclosure relates generally to latch assemblies; in particular, this disclosure relates to latch assemblies for selectively holding residential and/or commercial doors in a closed position. 
     BACKGROUND 
     A latch assembly is used for maintaining a door in a closed position using a bolt that moves between extended and retracted positions. In existing latches, the bolt is actively pushed and pulled between its extended and retracted positions. This pulling and pushing of the bolt requires a certain level of torque for the movement, which can present challenges for certain persons, such as the elderly, to exert sufficient torque to actuate the latch. Poor door preparation and environment factors can exacerbate these difficulties. For example, poor door preparation can create friction between the bolt and strike plate or pocket that increases the torque required to actuate the latch. 
     Another challenge with existing latches is adjustability. Latches need to fit the backset of the door, which is the distance between the door&#39;s edge to the center of the bore hole. Existing latch assemblies have limited adjustability for backset and can typically only be changed between two preset backset dimensions (e.g., 2.375 and 2.75 inches). Therefore, a consumer must determine a backset measurement to properly install a latch, which makes installation more complex and unforgiving to door prep. 
     SUMMARY 
     According to the present disclosure, assemblies, components and methodologies are provided for mounting a latch having an infinite backset (between the predetermined standard backsets) that allows opening and closing of doors with minimum application of torque on a door handle. In illustrative embodiments, a latch assembly is provided with a housing and a latch moveable between a latched position with a bolt extending out of the housing and an unlatched position in which the bolt is substantially inside the housing. A latch arm is coupled to the latch and configured to move to permit the latch to move between its latched and unlatched positions. Means for infinitely adjusting the backset is provided so that the lock assembly can be installed in a door without a predetermined backset measurement position. The means for infinitely adjusting the backset may slide along the latch arm along a predetermined path so that the backset can be adjusted to any position along the predetermined path during installation as needed. The means for infinitely adjusting the backset may further comprise a floating latch actuator coupled to the latch arm and an elongated slide opening in the housing, wherein the floating latch actuator is aligned with the elongated slide opening. 
     In some embodiments, a latch assembly comprises a housing and a bolt that pivots from a latched position during opening of a closed door. The latch arm is coupled to the latch and moves to permit the bolt to pivot from its latched position. In an illustrative embodiment, the latch assembly includes means for unblocking movement of the latch bolt. Once the bolt is unblocked, opening the door away from the door jamb (by pushing/pulling the door) will cause the latch bolt to swing so that the amount of force required to open or unlatch the door is reduced because the bolt will not drag (or apply an opposite force) on the strike on its way out of the strike box. The means for unblocking movement may include a latch actuator with a latch arm receiver sized to receive a portion of a latch arm and a biasing spring configured to bias the latch arm into a blocked position to block movement of the latch bolt. When the latch assembly is unblocked, the bolt is free to rotate when the door is pushed/pulled and a force is applied to the bolt. 
     In some embodiments, a latch assembly is provided with a housing and a latch that is moveable between a latched position and an unlatched position during opening and closing of a door. The latch assembly may include means for preventing unlatching of the bolt by having a latch arm that blocks pivoting of the bolt in a first position, and allowing unlatching of the bolt in a second position that unblocks the bolt to allow it to freely rotate. 
     Additional features of the present disclosure will become apparent to those skilled in the art upon consideration of illustrative embodiments exemplifying the best mode of carrying out the disclosure as presently perceived. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure will be described hereafter with reference to the attached drawings which are given as non-limiting examples only, in which: 
         FIG.  1    is a partial view of a door employing a latch assembly according to an embodiment of the disclosure; 
         FIG.  2    is a perspective view of a latch assembly according to an embodiment of the disclosure; 
         FIG.  2 A  is a perspective view of the latch assembly of  FIG.  2    rotated ninety-degrees counter-clockwise along its longitudinal axis to show additional components; 
         FIG.  2 B  is the latch assembly of  FIG.  2 A  with the sleeve partially cut away to show internal components; 
         FIG.  2 C  is a cross-sectional view taken along the line  2 C- 2 C of  FIG.  2 A ; 
         FIG.  3    is a perspective view of a latch assembly according to an another embodiment of the disclosure; 
         FIG.  3 A  is a perspective view of the latch assembly of  FIG.  3    rotated ninety-degrees counter-clockwise along its longitudinal axis to show additional components; 
         FIG.  3 B  is the latch assembly of  FIG.  3 A  with the sleeve partially cut away to show internal components; 
         FIG.  3 C  is a cross-sectional view taken along the line  3 C- 3 C of  FIG.  3 A ; 
         FIG.  4 A  is a perspective view of a latch assembly according to an embodiment of the disclosure having a dead latch; 
         FIG.  4 B  is the latch assembly of  FIG.  4 A  with the sleeve partially cut away to show internal components; 
         FIG.  4 C  is the latch assembly of  FIG.  4 B  showing the dead latch in the blocking position; 
         FIG.  5 A  is a side cross-sectional view of the latch assembly shown in  FIG.  4 A ; 
         FIG.  5 B  is a side cross-sectional view of the latch assembly shown in  FIG.  4 A  during door closing; 
         FIG.  5 C  is a side cross-sectional view of the latch assembly shown in  FIG.  4 A  upon door closing; 
         FIG.  5 D  is a side cross-sectional view of the latch assembly shown in  FIG.  4 A  showing dead lock activation; 
         FIG.  5 E  illustrates another view of the latch assembly taken along  5 E- 5 E of  FIG.  4 C  showing dead lock activation; 
         FIG.  6 A  is a partial cross-section of a latch assembly with a dead lock during door opening; 
         FIG.  6 B  illustrates the latch assembly of  FIG.  6 A  showing free rotation of the bolt while the dead lock is simultaneously deactivated by the arm; 
         FIG.  6 C  illustrates the latch assembly of  FIG.  6 A  showing the bolt position when clearing the door frame during door opening while the dead lock remains deactivated; 
         FIG.  6 D  illustrates the latch assembly of  FIG.  6 A  after the door has been opened; 
         FIG.  6 E  illustrates the latch assembly of  FIG.  6 A  fully returned to its biased position after the door has been opened; 
         FIG.  7    illustrates an exploded view of a camming assembly for a latch assembly according to an embodiment of the disclosure; 
         FIG.  8 A  illustrates a partial cross-sectional view of a latch assembly including the camming assembly of  FIG.  7    before operation of a door opening; 
         FIG.  8 B  illustrates a partial cross-sectional view of the latch assembly of  FIG.  8 A  after a door handle has been rotated; and 
         FIG.  9    illustrates a perspective cross-sectional view of a latch assembly including the camming assembly of  FIG.  7    after rotation of a door handle. 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     The disclosure generally relates to a latch assembly. The latch assembly is disclosed in one embodiment as part of a door handle assembly. The latch assembly as disclosed does not require activation (pull or push of the bolt) directly from the turning action of the door handle. Rather, the door handle will unblock the bolt, thereby allowing the bolt to rotate freely upon pushing or pulling the door. By providing a blocking and unblocking mechanism, rather than a direct translation mechanism that retracts the bolt, a lower torque will be required to release the bolt irrespective of the frictional conditions on the latch assembly. In some embodiments, the latch assembly has an infinite or variable backset that does not require a standardized or predetermined backset to function correctly. 
       FIG.  1    illustrates an example latch assembly  1  according to an embodiment of this disclosure installed in a door  7 . In this example, the latch assembly  1  includes a bolt  6  that rotates between a latched position (as shown in  FIG.  1   ) in which the bolt  6  extends from a face plate  11  and an unlatched position (see  FIG.  5 C ) in which an outer end of the bolt  6  moves to a position approximately flush with the face plate  11 . When closing the door, the bolt  6  is configured to slide or move inward into the latch assembly  1  when a camming surface of the bolt  6  engages with a door jamb or exterior of a strike plate (not shown) of the door frame, permitting the bolt  6  to move to the unlatched position approximately flush with the face plate  11  to clear the door jamb and enter a pocket (not shown) of the strike plate. After this, the bolt  6  is naturally biased back to the latched position and is retained in the pocket of the strike plate. Before opening the door, the bolt  6  is in the latched position and received in the strike plate pocket. When a force is applied to a flat surface of the bolt  6  (opposite the camming surface) from the door jamb when a user pushes or pulls on the door, the bolt  6 , is blocked from moving or pivoting to the unlatched position to keep the door  7  in a closed position. If a user actuates a door knob or handle to open the door, the bolt  6  is unblocked and freely pivots upon the force of the door jamb against the bolt  6  when the user pushes or pulls the door  7 . 
     When opening the door  7 , the latch assembly  1  is typically actuated by rotating a door handle, which could be a door knob, door lever, or other handle device. Unlike existing latch assemblies, however, the door handle is used to unblock the bolt  6 , which allows the bolt  6  to freely pivot to the unlatched position upon pushing/pulling the door  7 , instead of a direct mechanical push/pull translation to extend/retract the bolt. Embodiments are also contemplated in which latch assembly  1  could be employed in an electronic lock in which the latch assembly  1  may be actuated with a motor or other electronically-controlled mechanism to unblock the bolt  6 . In this example, there is an exterior door handle  15  and an interior door handle  3  that could each actuate the latch assembly  1  to unblock the bolt  6  to allow opening of the door  7 . In this example, the bolt  6  includes an angled surface  23  that slopes toward the exterior door handle  15  and a flat surface  67  that extends generally perpendicular to the latch assembly  1  and faces the interior door handle  3 . When the door is being closed, the angled surface  23  acts as a cam with the door jamb (not shown) to move the bolt  6  within the latch assembly  1 . When the door is closed, the flat surface  67  acts as a block against the door jamb to prevent the bolt  6  from being moved from engagement with the door jamb when the bolt  6  is blocked from pivotal movement (i.e. prevent the bolt  6  from moving to the unlatched position to permit opening of the door). 
       FIGS.  2  and  2 A  show the example latch assembly  1  of  FIG.  1    prior to installation in the door  7 .  FIG.  2 A  is a perspective view of the latch assembly of  FIG.  2    rotated ninety degrees counter-clockwise along its longitudinal axis  100  to show additional components. As shown, the latch assembly  1  includes a sleeve  2  that is slidably coupled with a cartridge  4 . When the latch assembly  1  is installed, the sleeve  2  and cartridge  4  are primarily disposed in the cross bore (not shown) in the door  7 . As shown, the sleeve  2  has an open first end  50  and a second end  52  extending into the cartridge  4 . The bolt  6  extends out of the sleeve  2  in its latched position (as shown) and is blocked from pivoting to keep the door closed as discussed below. When a user wants to open the door, actuating the door handle unblocks the bolt  6  so it can freely pivot to an unlatched position inside the sleeve  2  as the door is pushed/pulled. In this example, the sleeve  2  includes a radially extending flange  54  on its first end  50 , which could aid in maintaining a position of the sleeve  2  in the cross bore of the door  7 . The cartridge  4  includes side walls  56  that define a bore  5  through which the torque blade (not shown) of the door handle  3 ,  15  would extend to actuate the latch assembly  1 . In the example shown, the bore  5  is coaxial with a spindle receiver  30  (see also  FIG.  3 B ) to receive a torque blade of door handle  3 ,  15  that can be used to unblock the bolt  6 . In the example shown, the sleeve  2  is slidably coupled with a cartridge  4  to adjust backset of the latch assembly  1 . As shown, the sleeve  2  is slidable with respect to cartridge  4  along line  58  to adjust backset. Unlike existing latches that can only be selected between two predetermined backsets (i.e., 2.375 inches or 2.75 inches), the sleeve  2  is slidable to be infinitely adjustable by sliding the sleeve  2  with respect to the cartridge  4 . For example, the backset could be infinitely adjusted between a first backset and a second backset, which could be predetermined standard backsets. 
     Referring now to  FIGS.  2 B- 2 C , the latch assembly includes an inner sleeve  8  that is generally concentric with and slidably coupled with the sleeve  2 . The inner sleeve  8  is movable between an extended position and a retracted position. In the extended position (shown in for example  FIGS.  2 A,  2 C and  5 A ), the inner sleeve  8  has a proximal end  13  that is generally flush with the open first end  50  of the sleeve  2 . In the retracted position, the inner sleeve  8  slides toward the second end  52  of the sleeve  2  (see  FIGS.  5 B and  5 C ). A distal end  25  of inner sleeve  8  is urged by a push spring  14  towards its extended position. In one embodiment shown, a pin  62  extends from the inner sleeve  8  and receives the push spring  14 . As illustrated for example in  FIG.  2 C , the bolt  6  includes a protrusion  5  that is configured to abut against the proximal end  13  of the inner sleeve  8 . Alternatively, another portion of the bolt  6  may be configured to interact with the proximal end  13  of the inner sleeve  8 . When the door is being closed, the angled surface  23  of the bolt  6  acts as a cam with door jamb, causing the bolt  6  to move away from the latched position and apply an inward force to the inner sleeve  8 . This inward force upon the inner sleeve  8  overcomes the urging of the push spring  14  and moves the inner sleeve  8  to its retracted position. As the door continues to close, the bolt  6  will align with an opening in the strike plate (not shown). When this happens, no camming force will be applied to the bolt  6 , its protrusion  5 , or the inner sleeve  8 . The push spring  14  will accordingly urge the inner sleeve  8  back to its extended position, which moves the bolt to its latched position within the strike plate. Accordingly, the bolt  6  is urged towards its latched position by the urging of the push spring  14  on the inner sleeve  8  when the door is closed. 
     In the example shown, the bolt  6  is pivotally connected to the inner sleeve  8  with a pivot pin  60 . The bolt  6  is configured to at least partially pivot about the pivot pin  60  between its latched and unlatched positions when the door is being opened (e.g. when the bolt  6  is being moved out of engagement with the door jamb/strike plate of the door). A latch arm  12  selectively blocks pivoting of the bolt  6 . In the embodiment shown, the latch arm  12  has a proximal end  61  and a distal end  20 . The proximal end  61  includes a blocking surface  63  that is movable between a blocked position (as shown in for example  FIG.  2 C ) that blocks rotation of the bolt  6  about pivot pin  60  and an unblocked position that does not restrict rotation of the bolt  6  (see for example FIG.  6 A). The blocking surface  63  moves between the blocked position and the unblocked position based on a position of the distal end  20  of the latch arm  12  relative to other components such as the cartridge  4 . 
     As explained below, when a door handle is rotated to open the door, a torque blade (not shown) of a door handle will move the distal end  20  of the latch arm  12  from a first position (as shown for example in  FIGS.  3 C and  5 A ) in which the blocking surface  63  prevents pivotal rotation of the bolt  6  to a second position (as shown in  FIGS.  6 A- 6 C ) in which the blocking surface  63  allows the bolt  6  to rotate freely when the door is pushed/pulled. In particular, the force of the door jamb on the flat surface  67  of the bolt  6  will overcome the urging of a spring return  10  to pivot the bolt  6  within the sleeve  8 , as discussed below. In the example shown, the arm  12  is pivotally connected to the inner sleeve  8  by a pin  9 , which allows the latch arm  12  to pivot about pin  9  between the first position and the second position. Unlike existing latch assemblies, which retract the bolt by direct translation of the door handle, the door handle  3 ,  15 , in the present disclosure the latch assembly  1  only moves the latch arm  12  to block or unblock the bolt  6  so that it can freely pivot. Accordingly, in the present latch assembly  1 , actuation of the door handle  3 ,  15  does not to retract the bolt  6 ; instead, the door handle  3 ,  15  is merely used to move the latch arm  12  to block or unblock the bolt  6 . 
     In the embodiment shown, a spring return  10  urges the bolt  6  to the latched position in which the bolt  6  extends out of the open end of the sleeve  2 . As shown, the spring return  10  is coupled with the pin  60  and has a first end  66  engaged with the bolt  6  and a second end  68  engaged with a cross-member  70  of the latch arm  12 . With this configuration, the first end  66  of the spring return  10  urges the bolt  6  towards the latched position extending out of the sleeve  2 . Accordingly, when the latch arm  12  moves to the second position in which the bolt  6  is unblocked, when the user pushes/pulls the door  7 , this force on the flat surface  67  of bolt  6  will overcome the urging of the spring return  10  to pivot the bolt  6  within the sleeve  2 . As the door continues to open and the bolt  6  clears the door jamb, no additional force will be applied to the bolt  6 , and the spring return  10  will naturally urge the bolt  6  back to the latched position in which the bolt  6  extends out of the sleeve  2 . 
     As illustrated, for example, in  FIGS.  2 B and  2 C , the distal end  20  of the arm  12  may be engageable by a floating latch actuator  16  in the cartridge  4  that is engaged by the rotation of the torque blade to cause movement of the latch arm  12 . In one embodiment, the floating latch actuator  16  includes an arm receiver  18  for receiving the arm  12  and a bias spring  22 . The arm receiver  18  is movable when the torque blade is turned to cause the arm  12  to be moved to an unblocked position. The bias spring  22  urges the arm receiver  18  to a position that moves the arm  12  to a blocked position that prevents rotation of the bolt  6  about the pivot pin  60 . The blocked position is shown in  FIGS.  2 B and  2 C . Here, the bolt  6  is shown fully extended and blocked from moving distally inside the sleeve  2 . In this position, the blocking surface  63  of the arm  12  prevents free rotation of the bolt  6 . The spring return  10 , a torsion spring in the embodiment shown, urges the bolt  6  in the position illustrated. In various embodiments, the arm receiver  18  may further include an upper block  21  and a lower block  19 . The distance between the upper block  21  and the lower block  19  may be variable as the arm receiver  18  moves within the cartridge  4 . 
     In an illustrative embodiment, the arm receiver  18  may be moveable via a camming action when the arm receiver  18  is rotated upon opening the door. For instance, in one embodiment, the arm receiver  18  may float in and be movable relative to a cam block  17  (see  FIG.  2 B ) that interacts with the distal end  20  of the arm  12 . When a torque blade of the door handle rotates the arm receiver  18 , the cam block  17  may cam the distal end  20  of the arm  12  against the bias of the bias spring  22  to unblock the bolt  6 . In particular, this camming action causes the arm  12  to pivot against the urging of the bias spring  22  about the pin  9  to a position in which the blocking surface  63  does not prevent pivoting of the bolt  6 . In opening the door, a torque blade of the door handle will unblock or activate the floating latch actuator  16  to move the arm receiver  18  relative to the cam block  17  and compress the bias spring  22 , which moves the blocking surface  63  away from the bolt  6 . The arm receiver  18  could be moved by a camming mechanism wherein rotation of the arm receiver  18  cams out of cam block  17  to push the arm receiver  18  up against and compress the bias spring  22 . This raises the distal end  20  of the arm  12 , which in turn lowers the proximal end  61  of the arm  12  near the bolt  6 , allowing the bolt  6  to rotate against a strike plate (not shown). 
     In various embodiments, the arm receiver  18  may be engaged with a cam plug  29  that is fixed to a bottom surface of the cartridge  4 . The cam plug  29  is secured to the cartridge and does not rotate, but includes one or more surfaces that interact with the arm receiver  18  when the arm receiver  18  rotates. As illustrated in  FIGS.  7 - 9   , the cam plug  29  may be formed to include a lobe-receiving groove  31  defined by a first angled surface  33  and a second angled surface  35 . The lobe-receiving groove  31  is configured to receive and mate with a lobe  37  on an outer circumferential surface of the arm receiver  18  (for instance, on the lower block  19 ) to retain the arm receiver  18  in the position where the arm receiver  18  maintains the latch arm  12  in the blocked position. In various embodiments, there may be two or more lobes  37  on the arm receiver  18  that engage with two or more lobe-receiving grooves  31  of a cam plug  29 . The bias spring  22  is configured to urge the arm receiver  18  downward, thereby naturally urging the lobe  37  into mating engagement with the lobe-receiving groove  31 . When the arm receiver  18  is rotated by operation of the door handle (via, for example, force from the torque blade received in a spindle receiver  30  of the arm receiver  18 ), a camming surface  39  of the lobe  37  engages with the first angled surface  33  of the lobe-receiving groove  31  to slide the lobe  37  at least partially out of the lobe-receiving groove  31 . The camming surface  39  and first angled surface  33  are configured to mate and match against each other to perform this operation. This operation causes the arm receiver  18  to move upward toward the bias spring  22 . As illustrated in  FIG.  9   , the latch arm  12  may abut against a ride surface  41  of the arm receiver  18  to also move upward to the unblocked position. When force is no longer applied to the arm receiver  18  via the torque blade, the bias spring  22  will naturally bias the arm receiver  18  downward, causing the lobe  37  to slide along the first angled surface  33  back into full engagement with the lobe-receiving groove  31  of the cam plug  29 . As can be understood, a similar, but opposite, process may cause a second camming surface  43  of the lobe  37  to slide along the second angled surface  35  to raise the latch arm  12  with an opposite turn of the torque blade. Other embodiments of moving the arm receiver  18  upward upon rotation of a torque blade are envisioned herein. For instance, the arm receiver  18  may include one or more camming surfaces  39  and  43  or one or more ride surfaces  41  and  43  that cause a camming action but are not part of or connected to a lobe  37  or other similar feature. 
     When the door is being closed, the angled surface  23  of the bolt  6  acts as a cam against the door jamb. This allows the inner sleeve  8  to slide further inside the sleeve  2  against the biasing of the push spring  14  to clear the door jamb for opening the door. Although the push spring  14  is shown as a spring that lies on a side of arm  12 , it may be a larger spring that completely surrounds arm  12  and lies in axial alignment with inner sleeve  8  to provide equal force and equal biasing of the sleeve  8  to the extended position towards proximal end of the sleeve  2 . 
       FIG.  3    shows an embodiment of a latch assembly  24  that comprises a monolithic housing  26  assembly including a sleeve  2  and bolt  6 . In this embodiment, the sleeve  2  defines an elongated opening  28  that allows for an infinite or variable backset by adjusting the position of a spindle receiver  30 . The spindle receiver  30  may “float” or be translated along elongated opening  28  to any point along the opening, wherein the spindle receiver  30  aligns with the opening  28  to receive the torque blade of door handle  3 ,  15 . Therefore, the backset does not have to be predetermined, preset, or accurately measured to precisely align with a point in a bore hole of a door (not shown) before installation of the latch assembly  24  into the door. 
       FIGS.  3 B and  3 C  show cut-away and sectional views, respectively, of the monolithic assembly of  FIG.  3    to show internal components. Similar reference numbers in the monolithic housing assembly that are not discussed herein function the same as the corresponding components in the cartridge assembly described above with respect to  FIGS.  2 A- 2 C . As shown, the floating latch actuator  16  includes an arm receiver  18  and bias spring  22 . In this embodiment, the bias spring  22  is located between the upper block  21  of the arm receiver  18  and the lower block  19  of the arm receiver  18 . In this embodiment, when the door is being opened, turning the door handle causes a pushing actuation force to be exerted on the lower block  19  to compresses the bias spring  22  and pivots the distal end  20  of the arm  12  about the pin  9 . This pivoting action moves the blocking surface  63  away from the bolt  6 , thereby allowing free rotation of the bolt  6 . When the user opens the door, the force of the door jamb on the flat surface  67  of the bolt  6  will overcome the urging of the spring return  10  to allow pivoting of the bolt  6  about the pin  60 . 
       FIGS.  4 A- 7 E  illustrate an embodiment of the monolithic housing latch assembly  24  incorporating a dead latch  32 . Although depicted in the monolithic housing, the dead latch  32  as will be described in the following figures may also be incorporated into the latch assembly  1  with the cartridge  4 . In the embodiment shown, the dead latch  32  extends from the sleeve  2  along with the bolt  6  to provide additional security against forced entry via, for example, a knife or credit card. Similar reference numbers in this embodiment that are not discussed herein function the same as the corresponding components in the assemblies described above. 
     In the example shown, the dead latch  32  is located between guide prongs  34  of the bolt  6  and, when fully extended, has an end that is flush with a proximal end of the bolt  6 . As shown, the dead latch  32  is coupled to the arm  12  via a U-shaped blocker  36  and a lock lever  40 . The lock lever  40  has a dead latch receiver  44  for a distal end of the dead latch  32  to be received. The lock lever  40  is connected to and pivotable relative to the blocker  36 , via pivot points  42  formed in each side of the U-shaped blocker  36 . In this embodiment, the sleeve  2  and inner sleeve  8  each include blocker receiver openings  38  through which the ends of the blocker  36  may extend to block translation of the inner sleeve  8  and free rotation of bolt  6  when activated as best seen in  FIG.  4 C , for example. 
     As seen in  FIGS.  5 A- 5 B , illustrating the latch assembly  1  as a door closes with a door jamb, the dead latch  32  moves with the bolt  6  into the sleeve  2  along with the inner sleeve  8  when closing the door. During closing, the door jamb contacts the sloped surface  23  of the bolt  6  opposite the surface of the dead latch  32  to force the bolt  6  into the sleeve  2 . Once the door has cleared the door jamb and the bolt  6  is fully inside sleeve  2  as shown in  FIG.  5 C , the dead latch  32  will begin an activation process shown in  FIGS.  5 D- 5 E .  FIG.  5 D  shows the spring return  10  forcing the inner sleeve  8  and bolt  6  back out past the proximal end  50  of sleeve  8 . This translation results in corresponding movement of the arm  12  so that the proximal end  61  of the arm  12  near the bolt  6  rises and the distal end  20  lowers at the floating actuator  16 . The rising of the proximal end  61  of the arm  12  corresponds to a rise in the blocker  36  which pivots lock lever  40  (about pivot point  42 ) to be approximately parallel with the dead latch  32 . In this position, the blocker  36  extends through the blocker receiver openings  38  when the sleeve  8  translates into alignment with the receiver openings  38 , thereby blocking movement of the bolt  6 , inner sleeve  8 , and arm  12  when activated as seen in  FIG.  5 E . 
       FIGS.  6 A- 6 E  illustrate how the dead latch function is deactivated during the operation of opening the door.  FIG.  6 A  shows that the lower block  19  ( FIG.  5 B ) has been pushed towards upper block  21  ( FIG.  5 B ) to compress the bias spring  22  and raise the distal end of the arm  12 . This results in a corresponding lowering of the proximal end  61  of the arm  12  which lowers the blocker  36  out of the blocker receiver openings  38 . The lowering of the blocker  36  also pivots the lock lever  40  about the lever pivot  42 , causing the lock lever  40  to no longer be parallel with the dead latch  32 . When the lock lever  40  is no longer parallel with the dead latch, the dead latch  32  is free to move with the bolt  6 . Furthermore, the inner sleeve  8  is now free to translate within the sleeve  2  against the bias of push spring  14 . 
     As can be seen in  FIGS.  6 B- 6 C , the bolt  6  can freely rotate and forces exerted on the bolt  6  will force it inside the sleeve  2  as inner sleeve  8  translates towards the floating actuator  16  against the force of the push spring  14 . Meanwhile, the blocker  36  remains in an unblocking position allowing the free translation. Once the door jamb plate has been cleared and force is no longer acting to urge the bolt  6  and dead latch  32  inside the sleeve  2 , the push spring  14 , begins to return the inner sleeve  8  back to its initial position where the push spring  14  is unbiased.  FIG.  6 E  shows the latch assembly with the dead latch  32  returned to its unbiased configuration when the door is opened. 
     Although the present disclosure has been described with reference to particular means, materials and embodiments, from the foregoing description, one skilled in the art can easily ascertain the essential characteristics of the invention and various changes and modifications may be made to adapt the various uses and characteristics without departing from the spirit and scope of the invention. 
     EXAMPLES 
     Illustrative examples of the latch assembly and method of use disclosed herein are provided below. An embodiment of the latch assembly may include any one or more, and any combination of, the examples described below. 
     Example 1 is a latch assembly that includes a sleeve, a bolt, and a latch arm. The bolt is movable between a latched position in which the bolt extends out of the sleeve and an unlatched position in which the bolt is substantially inside the sleeve. The latch arm is positioned within the sleeve and includes a blocking surface movable between a blocking position that blocks the bolt from moving from the latched position to the unlatched position and an unblocked position that allows the bolt to move between the latched position to the unlatched position. 
     In Example 2, the subject matter of Example 1 is further configured such that the bolt is configured to pivot from the latched position, the bolt pivoting about an axis substantially transverse with a longitudinal axis of the sleeve. 
     In Example 3, the subject matter of Example 2 is further configured such that a bolt pin extends substantially transversely to the longitudinal axis of the sleeve, wherein the bolt is pivotally connected to the bolt pin. 
     In Example 4, the subject matter of Example 2 is further configured such that The latch assembly of claim  2 , further comprises a spring return configured to urge the bolt to pivot towards the latched position. 
     In Example 5, the subject matter of Example 1 is further configured such that the latch arm pivots between a first position in which the blocking surface is in the blocking position and a second position in which the blocking surface is in the unblocked position. 
     In Example 6, the subject matter of Example 5 is further configured such that a latch arm pin extends substantially transversely with respect to a longitudinal axis of the sleeve, and the latch arm is pivotally connected to the latch arm pin. 
     In Example 7, the subject matter of Example 1 is further configured such that an inner sleeve is slidably received by the sleeve, and the inner sleeve interacts with the bolt and slides relative to the sleeve when the bolt is moved between the latched position and unlatched position. 
     In Example 8, the subject matter of Example 7 is further configured such that a biasing member is configured to urge the inner sleeve into engagement with the bolt. 
     In Example 9, the subject matter of Example 8 is further configured such that the biasing member naturally urges the bolt into the latched position. 
     In Example 10, the subject matter of Example 7 is further configured such that the bolt is configured to slideably move within the sleeve. 
     In Example 11, the subject matter of Example 10 is further configured such that the bolt is configured to pivot from the latched position, and the bolt pivots about an axis substantially transverse with a longitudinal axis of the sleeve. 
     In Example 12, the subject matter of Example 1 is further configured such that the latch assembly further includes an inner sleeve coupled to the latch arm and a means for preventing unlatching of the bolt. The inner sleeve is configured to slide longitudinally within the sleeve, and the inner sleeve urges the bolt toward the latched position. The means for preventing unlatching of the bolt includes blocking sliding movement of the inner sleeve in the housing. 
     In Example 13, the subject matter of Example 12 is further configured such that the means for preventing unlatching of the bolt includes a dead latch having a latch blade, a rotatable lever, and a blocker coupled to the latch arm and the rotatable lever. A force exerted on the latch blade results in rotation of the rotatable lever and further results in translation of a portion of the blocker into one or more openings in the inner sleeve to prevent sliding movement of the inner sleeve. 
     In Example 14, the subject matter of Example 13 is further configured such that the rotatable lever is in an angled position when the dead latch permits movement of the latch, and the rotatable lever rotates so that it is positioned parallel to a longitudinal axis of the housing when the dead latch prevents movement of the latch. 
     In Example 15, the subject matter of Example 13 is further configured such that the blocker is U-shaped and the rotatable lever includes an opening configured to receive a distal portion of the latch blade there through. 
     In Example 16, the subject matter of Example 13 is further configured such that the rotatable lever is configured to pivotally rotate about a point where the rotatable lever is attached to the blocker. 
     Example 17 is a latch assembly including a housing, a bolt, a latch arm, and a means for infinitely adjusting a backset of the latch assembly. The bolt is moveable between a latched position extending out of the housing and an unlatched position in which the bolt is substantially inside the housing. The latch arm is configured to move with the bolt when the bolt moves between the latched and unlatched positions. The means for infinitely adjusting a backset of the latch assembly permits adjustment relative to an elongated slide opening of the housing so that the latch assembly may be installed in a door without a predetermined backset measurement position. 
     In Example 18, the subject matter of Example 17 is further configured such that the means for infinitely adjusting the backset slides along the latch arm along a predetermined path so that the backset can be adjusted to any position along the predetermined path. 
     In Example 19, the subject matter of Example 17 is further configured such that the means for infinitely adjusting the backset includes a floating latch actuator coupled to the latch arm and to the elongated slide opening in the housing, wherein the floating latch actuator is aligned with the elongated slide opening. 
     Example 20 is a method of operating a latch assembly. The method includes the step of providing a latch assembly installed on a door, the latch assembly including a bolt moveable between a latched position and an unlatched position, and the latch assembly further including a latch arm movable between a first position that blocks pivoting of the bolt and a second position that does not block pivoting of the bolt. The method further includes moving the latch arm from the first position to the second position by rotating a door handle. The method further includes pivoting the bolt away the latched position and moving the bolt to the unlatched position by opening the door.