Abstract:
A device for securing a spindle to a hub in a mortise lock for a door. The device includes a hub defining a central opening about an axis of rotation and a spindle with a first end adapted to be received in the opening in the hub to apply rotational force to the hub. A securing element is moveable between a first position in which the securing element engages the spindle and the spindle is secured to the hub, and a second position in which the securing element is disengaged from the spindle and the spindle may be freely removed from the opening in the first hub. The securing element may be adapted for reciprocal linear movement in the housing, and may engage the first spindle by part of the securing element being received in a peripheral groove in the spindle.

Description:
BACKGROUND 
     Embodiments described herein relate generally to door latches, and more particularly to latch operator connection apparatus for a mortise lock that is inserted in a mortise in the edge of a door. 
     A mortise lock includes a housing with, among other things, a hub rotatably disposed in the housing and operatively connected through linkages to a latch bolt. Rotating the hub in one direction effects linear retraction of the latch bolt. A latch operator such as a knob or a lever handle is provided for rotating the hub. A spindle, which is usually square in cross section, connects the latch operator and the hub. The hub defines a receptacle, also usually square, for nonrotatably receiving the spindle. When either handle is rotated or depressed, the hub rotates, which results in retraction of the latch bolt, allowing opening of the door. Two separate hubs may be provided in a mortise lock, where inside and outside latch operators independently operate each hub. The two hubs are coaxial, but are functionally separate from one another. 
     Some configurations of a spindle may include a unitary spindle that extends through the case and is secured at each end to the inside and outside latch operators, respectively. In this arrangement, the inside handle is permanently engaged with the hub and the outside handle. A second configuration consists of separate spindles for each of the latch operators. The separate spindles may be joined at their inner ends by an “all-thread” threaded rod such that the spindles are connected but may rotate relative to one another. This second configuration can be used with a single hub or two independent hubs. In the latter arrangement, the latch operators separately actuate the hub or hubs. Assembly and disassembly may require significant time and effort. 
     SUMMARY 
     In accordance with one embodiment, a spindle connecting device for a mortise lock is provided. The mortise lock includes a housing and a latch bolt disposed at least in part in the housing. The latch bolt is adapted for reciprocal linear movement and is operable with a latch operator. The device includes a first hub defining a central opening about an axis of rotation, with the first hub adapted to operatively communicate with the latch bolt to transmit force to retract the latch bolt. A first spindle has a longitudinal axis, a first end, and a second end. The first end is adapted to be received in the opening in the first hub and to apply rotational force to the first hub. The second end of the first spindle is adapted to operatively communicate with the latch operator. A securing element is provided that is moveable between a first position in which the securing element engages the first spindle and the first spindle is secured to the first hub, and a second position in which the securing element is disengaged from the first spindle and the first spindle may be freely removed from the opening in the first hub. In some such embodiments, the first spindle defines a first peripheral groove proximate to the first end. The securing element may be adapted for reciprocal linear movement in the housing, movable in a direction substantially perpendicular to the longitudinal axis of the first spindle. The securing element may also engage the first spindle by part of the securing element being received in the first peripheral groove, and the securing element may be disengaged from the first spindle by the securing element being completely outside the first peripheral groove. 
     In some embodiments, the securing element includes a first end, a second end, and two spaced, parallel sides extending from the first end, each side including a lip portion spaced from the first end, and the part of the securing element received in the groove in the first position is part of the lip portion. In such embodiments, the two sides of the securing element define opposing slots in the sides aligned with the direction of linear movement of the securing element, and further include a retaining element slidably mounted to the securing element between the two sides and in the slots of the securing element and adapted to be mounted to the housing, and means for biasing the first end of the securing element away from the retaining element. 
     In accordance with another embodiment, another spindle connecting device is provided. The device includes a first hub defining a central opening about an axis of rotation. The first hub is adapted to operatively communicate with the latch bolt to transmit force to retract the latch bolt. A first spindle has a longitudinal axis, a first end, and a second end, and the first end adapted to be received in the opening in the first hub and to apply rotational force to the first hub. The first spindle defines a first peripheral groove proximate to the first end, and the second end of the first spindle is adapted to be mounted to the latch operator. Means for securing the first spindle to the first hub at the first peripheral groove are provided. In some embodiments, a second spindle is provided having a longitudinal axis, a first end, and a second end, and the second spindle first end is adapted to be received in the opening in the second hub and to apply rotational force to the second hub. The second spindle defines a second peripheral groove proximate to the first end, and the second end of the second spindle is adapted to operatively communicate with the latch operator. The means for securing the first spindle to the first hub also secures the second spindle to the second hub at the second peripheral groove. 
     In accordance with another embodiment, a mortise lock operable with a latch operator is provided. The mortise lock includes a housing, a latch bolt disposed at least in part in the housing for reciprocal linear movement, a first hub, a first spindle, and a securing element. The first hub defines a central opening about an axis of rotation and is in operative communication with the latch bolt to transmit force to retract the latch bolt. The first spindle has a longitudinal axis, a first end, and a second end. The first end is received in the opening in the first hub to apply rotational force to the first hub. The second end of the first spindle is in operative communication with the latch operator. The securing element is moveable between a first position in which the securing element engages the first spindle and the first spindle is secured to the first hub, and a second position in which the securing element is disengaged from the first spindle and the first spindle may be freely removed from the opening in the first hub. 
     In some embodiments, the securing element includes a first end, a second end, and two spaced, parallel sides extending from the first end, each side including a lip portion spaced from the first end, and the part of the securing element received in the groove in the first position is part of the lip portion. In such embodiments, the two sides of the securing element define opposing slots in the sides aligned with the direction of linear movement of the securing element, and further include a retaining element slidably mounted to the securing element between the two sides and in the slots of the securing element and mounted to the housing, and means for biasing the first end of the securing element away from the retaining element. 
     In accordance with another embodiment, a method of assembling a spindle in a mortise lock operable with a latch operator is provided. The mortise lock includes a housing, a latch bolt disposed at least in part in the housing for reciprocal linear movement, a hub, a spindle, and a securing element. The hub defines a central opening about an axis of rotation, the hub in operative communication with the latch bolt to transmit force to retract the latch bolt. The spindle has a longitudinal axis, a first end, and a second end. The first end is received in the opening in the hub to apply rotational force to the hub. The spindle defines a peripheral groove proximate to the first end, and the second end of the spindle is adapted to be mounted to the latch operator. The securing element is disposed in the housing for reciprocal linear movement, with the securing element movable in a direction substantially perpendicular to the longitudinal axis of the spindle. The method includes inserting the first end of the spindle into the opening in the hub, and contacting the securing element with the first end of the spindle. The first end of the spindle is advanced further into the opening in the hub to move the securing element out of the path of the first end of the spindle. Then the first end of the spindle is further advanced into the opening in the hub until the groove in the spindle reaches the securing element and the securing element advances into the groove. In some embodiments, the method further includes applying force to the securing element to move the securing element out of the groove, and withdrawing the first end of the spindle from the opening in the hub. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding, reference should now be had to the embodiments shown in the accompanying drawings and described below. In the drawings: 
         FIG. 1  is a left perspective view of an embodiment of a mortise lock, cover plate, spindles, and latch operators. 
         FIG. 2  is a right perspective view of an embodiment of a mortise lock, cover plate, spindles, and latch operators. 
         FIG. 3  is a partially exposed left perspective view of the mortise lock of  FIG. 1  showing an embodiment of a latch operator mounting device. 
         FIG. 4  is an exploded perspective view the mortise lock of  FIG. 1  showing the embodiment of a latch operator mounting device of  FIG. 3 . 
         FIG. 5  a perspective view of the latch operator mounting device of  FIG. 3 . 
         FIG. 6  is an exploded perspective view of the latch operator mounting device of  FIG. 3 . 
         FIG. 7  is a left side view of the latch operator mounting device of  FIG. 3 . 
         FIG. 8  a top view of the latch operator mounting device of  FIG. 3 . 
         FIG. 9  is a rear view of the latch operator mounting device of  FIG. 3 . 
         FIG. 10  is a side elevation view of an embodiment of one of the two hubs of the latch operator mounting device of  FIG. 2 . 
         FIG. 11  is an opposite side elevation view of the hub of  FIG. 10 . 
         FIG. 12  is an end view of the hub of  FIG. 10 . 
         FIG. 13  is a partially exposed, partially exploded, left perspective view of the mortise lock, spindles, and latch operators of  FIG. 1  showing the operation of the latch operator mounting device of  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION 
     The embodiments of a door latch operator connection device described herein may be for use with a conventional mortise lock for a conventional door, including, for example, a door hinged on a vertical edge or a sliding door. Moreover, it is understood that the overall construction of the mortise lock components and the door is not critical. Accordingly, although exemplary embodiments will be described in detail herein with respect to a mortise lock function, detailed explanations of the functioning of the mortise lock components are deemed unnecessary for understanding by one of ordinary skill in the art. 
     Certain terminology is used herein for convenience only and is not to be taken as a limitation. For example, words such as “front,” “back,” “top,” “bottom,” “rear,” “upper,” “lower,” “left,” “right,” “horizontal,” “vertical,” “upward,” and “downward” merely describe the configuration shown in the figures. The components may be oriented in any direction and the terminology, therefore, should be understood as encompassing such variations unless specified otherwise. 
     Referring now to the drawings, wherein like reference numerals designate corresponding or similar elements throughout the several views, an embodiment of a mortise lock for use on a conventional hinged door is shown in  FIGS. 1 and 2  and is generally designated at  40 . The mortise lock  40  will be inserted into a rectangular opening or mortise in the edge of a door  41 . 
     The mortise lock  40  includes a housing  42 , which includes a case  44 , a cover  46  mounted to the case  44  with fasteners, shown as screws  48 , and a base front  50  also mounted to the case  44 . The base front  50  is conventionally mounted to a recessed area in the door edge. An armor front  52  is mounted to the base front  50  with screws  53  that extend through holes  54  in the base front  50 , and covers the front side of the base front  50 . The mortise lock  40  is mounted to the door with screws (not shown) that extend through holes  55  at the top and bottom of the base front  50 . Reinforcing  56  is provided on the back side of the base front  50  around the holes  55 . Direction arrow  58  shows the general designations of front and back of the mortise lock  40 , with front being at the armor front  52 . 
     In the embodiment shown, the armor front  52  has an aperture  60  for a latch  62 . Spindles  64  are operatively connected to the latch  62 , and latch operators, in this case levers  68 , are connected to the spindles  64 . 
     In  FIG. 3 , the armor front  52  is removed to expose the front of the base front  50 . The base front  50  defines apertures that may allow features to pass through the base front  50 . One aperture  72  may be used for a deadbolt, not included in this embodiment. Another aperture  74  allows the latch to pass through. A third aperture  76  is for a guard bolt for effectively deadbolt the latch bolt when pushed inward, also not included in this embodiment. A fourth aperture  78  is for a toggle button for keeping the latch  62  in a constant locked or unlocked state, not shown. If a deadbolt and a guard bolt were provided, there would be corresponding apertures in the armor front  52 . 
     The housing cover  46  is truncated in  FIG. 3  to expose a portion of an embodiment of a latch operator mounting device  80  mounted to the case  44  and cover  46 . The embodiment of a latch operator mounting device  80  is shown in  FIGS. 4-9 , and includes spindles  64 , hubs  82 ,  84 , center ring  86 , spindle catch  90 , retainer  92 , and spring  94 . 
     The spindles  64  may be elongated and substantially square in cross section. The spindles  64 , as shown in this embodiment, may have the same shape and be duplicate parts. The inner end  100  of each spindle  64  may be tapered or have beveled corners, and proximate to the inner end  100  is a peripheral groove  104 . At the peripheral groove  104  the spindles  64  may have a circular cross section. An opening  108  is provided on one face of each spindle  64  to receive a roll pin  110  that is disposed in an aperture  112  through the collar  114  of the levers  68 . An opening in each lever  68  at the collar  114  receives an outer end  122  of the adjacent spindle  64 , and has longitudinal notches  126  to prevent the spindle  64  from rotating relative to the lever  68 . 
     As shown in  FIG. 6 , the spindle catch  90 , which may be a means for securing a spindle  64  to a hub  82 ,  84 , may be formed from a stamped sheet or plate into a substantially U-shaped member, with a closed end  130  at the front and an open end at the back, and sides  134  extending from the closed end  130 . The lower portion of the spindle catch  90  may be elongated and includes a slot  136  on each side that receives prongs  138  that are at each end of the retainer  92 , which between the prongs  138  may be a substantially planar member. The open ends of the spindle catch  90  allow outward deflection of the sides  134 , which in turn permits mounting of the retainer  92  in the spindle catch  90 . The spring  94 , which in this embodiment is a coil spring, is placed in between the retainer  92  and the closed end  130  of the spindle catch  90  to bias the closed end  130  of the spindle catch  90  and the retainer  92  apart. The latch operator mounting device  80  is mounted in the mortise lock housing by insertion of the prongs  138  into an opening  140  through the cover  46  and an opening  142  through the side of the case  44  ( FIGS. 1 and 2 ). Consequently, the retainer  92  is in a fixed position in the housing  42 , and the spindle catch  90  is slidably disposed in the housing  42 , with movement permitted, and constrained, by the slots  136  in the sides of the spindle catch  90 . 
     Spaced from the front end  130  of the spindle catch  90 , and, in the embodiment shown, at the back end  132  of the spindle catch  90 , the sides  134  extend upward and form lips  144 . The lips  144  may be substantially U-shaped, with the open end facing the front of the mortise lock  40 . At the closed end of the “U” is an engagement portion  146 . The engagement portion  146  has an arc-shaped recess, and is received in the peripheral groove  104  in the adjacent spindle  64 . The shape of the recess permits the spindle  90  to rotate, while the engagement portion  146  is within the groove  104 . 
     The hubs  82 ,  84  include a central portion  150 ,  152  and an arm  154 ,  156  extending from the central portion  150 ,  152 . The hubs  82 ,  84  are rotatably disposed in the mortise lock case  44 , and are operatively connected to a latch bolt  160  ( FIG. 4 ). Rotating the hub  82 ,  84  in one direction rotates the respective arm  154 ,  156  to apply force to the latch tail  162  and effects linear retraction of the latch bolt  160 . The central portion  150 ,  152  of each hub  82 ,  84  defines a square receptacle  164  to receive the inner end  100  of the spindle  64 , whereby each hub  82 ,  84  rotates with its respective spindle  64  when that spindle  64  is rotated by depressing the associated lever  68 . The receptacle  164  may not pass entirely through the central portion  150 ,  152 , such that the spindle  64  abuts the back of the receptacle  164  and is prevented from passing through the central portion  150 ,  152 . The hubs  82 ,  84  are coaxial but functionally separate, being rotatably mounted to each other, whereby each rotates independently from the other one. A center ring  170  may be interposed between the central portions  150 ,  152  to support the hubs  82 ,  84 , or alternatively such a structure could be integral to one of the hubs  82 ,  84 . 
     The lips  144  of the spindle catch  90  axially position the hubs  82 ,  84 , as the hubs  82 ,  84  are mounted substantially between the lips  144 . A collar  166  on each hub extends axially outside the lips  144 , and a slot  168  is provided in each collar  166  that receives the engagement portion  146  of the lips  144  to allow the engagement portion  146  to reach the groove  104  in the spindle  90 . When the engagement portion  146  is in the groove  104 , the engagement portion  146  impedes withdrawal of the spindle  90  from the receptacle  164 . 
       FIGS. 10-12  show a hub  82 . The other hub  84  may be, as shown, a mirror image of this hub  82 , or may have a different structure. As previously noted, the hubs  82 ,  84  each have a central portion  150 ,  152 , an arm  154 ,  156 , and a collar  166 . A slot  172  is also provided in each collar  166  to receive an engagement portion  146  of a lip  144  of a spindle catch  90 . Each hub  82 ,  84  has an inner surface with a cylindrical protrusion  174  that is received in the center ring  170  that maintains the ring  170  and the hubs  82 ,  84  in registration. 
     The components of the mortise lock housing  42 , the spindle catch  90 , the spindles  64 , the hubs  82 ,  84 , and the levers  68  may generally be metal, such as carbon steel or stainless steel, or other material as selected by one of ordinary skill in the art. The retainer  92  may be, for example, plastic, such as nylon in one embodiment, or other material as selected by one of ordinary skill in the art. 
       FIG. 13  shows the mortise lock  40  with the cover  46  removed. The arms  154 ,  156  of the hubs  82 ,  84  abut the inner surface of the tail  162  of the latch bolt  160 , and linearly displace the latch bolt  160  when the respective lever  68  is depressed. Once the lock  40  is installed in the mortise lock pocket of the door  41 , the lever assemblies, each including a lever  68  mounted to a spindle  90  with a roll pin  110 , are ready to be installed. The spindle inner end  100  is inserted into the receptacle in the hub  82 ,  84 . As the inner end  100  is inserted, it is impeded slightly on one edge by the engagement portion  146  of the lip  144  of the spindle catch  90 . The spindle catch  90  is spring loaded, or biased, inward toward the spindle  64 . The inner end  100  of the spindle  64  forces the engagement portion  146  to retract from the receptacle  164 , and the inner end  100  is inserted further. When the inner end  100  is inserted to a certain point, the peripheral groove  104  reaches the engagement portion  146 , which continues to be biased against the side of the spindle  64 . At that time, the engagement portion  146  enters the groove  104 , locking the spindle  90  in place. The spindle  90  effectively is “snapped into” position. 
     To remove the spindle  64  from the hub  82 ,  84 , first the armor front  52  ( FIG. 1 ) is removed from the base front  50 . At bottom of the lowest aperture  78  in the base front  50 , space may be provided for a screwdriver  180  to be inserted  182  through the base front  50  and to apply force to the spindle catch  90  toward the back of the mortise lock  40 . A small aperture  184  may be provided in the front surface of the spindle catch  90  to facilitate engagement by the screwdriver  180 . The spindle catch  90  is displaced rearward, against the bias of the spring  94 , and accordingly the engagement portion  146  is displaced from the peripheral groove  104  in the spindle  64 . When this occurs, the lever  68  and spindle  64  may be removed from the hub  82 ,  84  by pulling away from the door  41 , and are thereby disassembled from the mortise lock  40 . 
     Although only a few exemplary embodiments have been shown and described in considerable detail herein, it should be understood by those skilled in the art that we do not intend to be limited to such embodiments since various modifications, omissions and additions may be made to the disclosed embodiments without materially departing from the novel teachings and advantages, particularly in light of the foregoing teachings. Accordingly, we intend to cover all such modifications, omission, additions and equivalents as may be included within the spirit and scope as defined by the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures.