Abstract:
The present invention addresses the need of the industry for a simple and comfortable latch mechanism that automatically latches a window when the window is returned to a closed position. A latch mechanism for a window includes a housing defining an opening therein, a latch bolt slidably disposed in the housing and selectively positionable between an extended position and a retracted position wherein such latch bolt is adapted to be actuated by an actuating mechanism from the retracted position to the extended position, and a stopping mechanism adapted to automatically engaged and retain the latch bolt in the retracted position as the latch bolt is positioned from the extended to the retracted position.

Description:
TECHNICAL FIELD 
     The present invention relates to windows, and more specifically, to latching mechanisms for windows. 
     BACKGROUND OF INVENTION 
     Double hung and other sliding sash type windows are very common. Typically, a latch or locking mechanism is used to secure the sashes in place to inhibit unintentional opening of the sashes and unauthorized entry to the structure. 
     One very common mechanism used to lock sashes together is the so-called check rail lock, which includes a sweep cam attached to a rotatable handle. The check rail lock is mounted on one of the sashes, usually the lower sash of a double-hung window proximate the center of the sash rail. A keeper structure is mounted on the other sash proximate the check rail lock. As the handle is rotated in either direction, the sweep cam is rotated into or out of engagement with the keeper in order to enable locking or opening of the window as desired. A drawback of these devices, however, is that the handle can be rotated so that the sweep cam is extended even when the sash is open. When the sash is closed with the sweep cam in such position, the extended position of the sweep cam prevents full closure of the sash. The operator of the window may not notice the window is not fully closed and latched. In addition, the sweep cam may strike and damage the other sash. 
     Another prior mechanism includes a sliding latch bolt that may be mounted on one sash and that is selectively engageable with a keeper mounted on the other sash. A drawback with these mechanisms, however, is often that the bolt must be held in a retracted position as the window is operated. In other case, where a mechanism for holding the bolt in a retracted position is employed, the bolt either releases as soon as the window is raised, or must be manually released with a separate catch or button. In such cases, the window may fail to close fully and may not be noticed by the operator of the window. 
     Some prior mechanisms have tried to solve the above problems, but the solutions are relatively complicated for manufacturers and customers. What is still needed is a more simple and comfortable latch mechanism for a window that automatically latches when the window is returned to a closed position. 
     SUMMARY OF THE INVENTION 
     The present invention addresses the need of the industry for a simple and comfortable latch mechanism that automatically latches a window when the window is returned to a closed position. According to an embodiment of the invention, a window is equipped with a latch mechanism having a latch bolt and a spring driven actuating mechanism in the housing of the latch mechanism. The latch mechanism is mounted on a sash of a window assembly opposite a keeper or similar latch bolt receiving structure. With the window in a closed position, the latch bolt of the latch mechanism is received in the keeper to latch the sashes together, and the actuating mechanism is confined in a retracted position by the keeper. To open the window, the latch mechanism is disengaged from the keeper by grasping a finger grip on a trigger cap and pulling outwardly away from keeper. The latch bolt slides out of the keeper and goes into the housing, and the actuating mechanism is released by the keeper and extends outwardly from the housing and reaches an extended position. The latch bolt is held in a retracted position by a stopping mechanism in the housing of the latch mechanism. With the latch bolt in this position, the sash may be moved to open the window. To close the window, the sash with the latch mechanism is moved toward the keeper. The outwardly extending portion of the actuating mechanism contacts the keeper that pushes the actuating mechanism inwardly into the housing. The actuating mechanism actuates the latch bolt and disengages the latch bolt from the stopping mechanism. A spring urges the latch bolt forwardly so that it is once again engaged in the keeper and the sashes are latched together as before. According to one embodiment, when latch bolt is in the retracted position, it can also be disengaged from the holding mechanism by pushing the finger grip toward the extended position of the latch bolt. The finger grip can move along a curved track on the curved upper surface of the housing. 
     According to one embodiment, a latch mechanism for a window includes a housing defining an opening therein, a latch bolt slidably disposed in the housing and selectively positionable between an extended position and a retracted position wherein such latch bolt is adapted to be actuated by an actuating mechanism from the retracted position to the extended position, and a stopping mechanism adapted to automatically engaged and retain the latch bolt in the retracted position as the latch bolt is positioned from the extended to the retracted position. There is a sliding ridge on the inside surface of the housing, and the sliding ridge defines the moving track of a sliding contactor on an actuating mechanism. The actuating mechanism includes a contacting pin adapted to slide along a closed curve defined by the sliding ridge, wherein the actuating mechanism is arranged to extend outwardly from the housing without actuating the latch bolt as the contacting pin goes along one section of the closed curve, and to retract inwardly to the housing and actuate the latch bolt as the contracting pin goes along the other section of the closed curve. 
     Embodiments of the housing of the latch mechanism may include a top cover and a bottom cover. A hook mechanism and a plug-socket mechanism are coupled with the top cover and the bottom cover. The top and the bottom covers can be held together in two steps. The first step is that the plug-socket mechanism holds the top cover and the bottom cover together when the hook mechanism does not hold the top cover and the bottom cover. The second step is that the hook mechanism holds the top cover and the bottom cover together with the plug-socket mechanism. 
     The advantage of this invention is a simple and comfortable solution for manufacturers and consumers to manufacture, assemble, install, and use an automatic latch for a window. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is one exemplary embodiment of this invention. 
         FIG. 2  is a top exploded view of the exemplary embodiment in  FIG. 1 . 
         FIG. 3  is a bottom exploded view of the exemplary embodiment in  FIG. 1 . 
         FIG. 4  is a detailed view of the actuator in  FIG. 1 . 
         FIG. 5  is a detailed view of the base cover in  FIG. 1 . 
         FIG. 6  is a detailed bottom view of the latch bolt in  FIG. 1 . 
         FIG. 7  is a detailed top view of the latch bolt in  FIG. 1 . 
         FIG. 8  is one exemplary assembly process of the latch mechanism in  FIG. 1 . 
         FIG. 9  A-D show a detailed process of assembling a latch bolt into a base cover. 
         FIG. 10  A-B show a detailed process of mounting the assembled top cover to the assembled base cover. 
         FIG. 11  shows the sliding track of the trigger cap on the arc side of the top cover. 
         FIG. 12  A-C show detailed connection between the trigger cap and the latch bolt in the locked position and unlocked position of the latch mechanism. 
         FIG. 13  A-D show an acting process of a latch mechanism. 
         FIG. 14  A-E show a detailed actuating process of a latch mechanism. 
         FIG. 15  A-J show different embodiments with various trigger caps and screw holes. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is one exemplary embodiment of this invention.  FIG. 2  is a top exploded view of the exemplary embodiment in  FIG. 1 . Latch mechanism  100  generally includes housing  110  (shown in  FIG. 1 ), latch bolt  118 , trigger cap  114 , one resilient element that can be base spring  122 , actuator  120 , and another resilient element that can be actuator spring  124 . Latch mechanism  100  and latch keeper  126  together constitute a lock mechanism  99  (shown in  FIG. 1 ). Those skilled in the art will realize and understand, upon reading this description, that other and or different resilient elements may be used to fulfill the same function. Housing  110  generally includes top cover  112  and base cover  116 . Base cover  116  generally includes front wall  134 , rear wall  138 , and bottom wall  136 . Front wall  134  and bottom wall  136  together define openings known as latch bolt aperture  130  and actuator aperture  132 . Rear wall  138  includes base spring post  139 . Base cover  116  further has actuator guide slot  140 , latch bolt guide slot  142 , and latch bolt aperture beam  144 . Actuator guide slot  140  and latch bolt guide slot  142  extend from front wall  134  to rear wall  138 . Latch keeper  126  generally includes latch keeper socket  127 , keeper bevel wall  128 , and latch bolt receiver  125  (shown in  FIG. 3 ). 
       FIG. 3  is a bottom exploded view of the exemplary embodiment in  FIG. 1 . Trigger cap  114  generally includes short cap shaft  150 , long cap shaft  152 , and a pair of cap hooks  154 . Top cover  112  generally includes a pair of top cover slots  156 , a pair of cap hook guide slots  158 , a pair of upper plugs  160 , and a pair of upper hooks  162 . 
       FIG. 4  is a detailed view of actuator  120  in  FIG. 1 . Actuator  120  generally includes actuator spring post  121  (shown in  FIG. 3 ), actuator arm  170 , actuating pin  172 , and a sliding contactor known as contacting pin  174 . Those skilled in the art will realize and understand, upon reading this description, that other and or different sliding contactors may be used to fulfill the same function. 
       FIG. 5  is a detailed view of base cover  116 . Base cover  116  further includes base stopping pin  180 , base chamfer  182 , harbor area  183 , base stud  184 , base arc side  186 , and base limit wall  188 . Base stopping pin  180  and latch stopping pin  196  (shown in  FIG. 6 ) constitute a stopping mechanism. Those skilled in the art will realize and understand, upon reading this description, that other and or different stopping mechanisms may be used to fulfill the same function. 
       FIG. 6  is a detailed bottom view of latch bolt  118 . Latch bolt  118  generally includes base spring slot  192 , flexible tab  194 , latch stopping pin  196 , latch trigger pin  198 , and latch bolt arm  200 .  FIG. 7  is a detailed top view of latch bolt  118 . Latch bolt  118  further includes a confining element and a pair of latch bolt slots  204 . One embodiment of the confining element can be latch assembly limit  202 . 
     In addition, those skilled in the art will realize and understand, upon reading this description, that other and or different architectures may be used to build this invention. 
     One exemplary assembly process is shown in  FIG. 8 . The exemplary assembly process generally includes the flowing steps. Base spring  122  is mounted on base spring post  139 . Latch bolt  118  is positioned through latch bolt aperture  130  into latch bolt guide slot  142 , wherein base spring  122  fits into base spring slot  192 . Actuator spring  124  is mounted in the actuator guide slot  140 . Actuator  120  is positioned into actuator guide slot  140  with actuator spring post  121  fitting into actuator spring  124  and with actuator  120  extending from actuator aperture  132 . These steps lead to assembled base cover  210  (shown in  FIG. 8 ). 
     Trigger cap  114  is slidably disposed on top cover  112  with short cap shaft  150  and long cap shaft  152  extending through each of top cover slots  156  and with each of cap hooks  154  extending through a separate one of cap hook guide slots  158 . These steps lead to assembled top cover  212  (shown in  FIG. 8 ). 
     Assembled top cover  212  is mounted on assembled base cover  210  with short cap shaft  150  and long cap shaft  152  fitting into a separate one of latch bolt slots  204 , with each one of upper plugs  160  fitting into a separate one of bottom slots  146 , and with each one of upper hooks  162  snapping on a separate one of bottom hooks  148 . These steps lead to latch mechanism  100 . The upper hooks  162  and the bottom hooks  148  constitute a hook mechanism. The upper plugs  160  and the bottom slots  146  constitute a plug-socket mechanism. Those skilled in the art will realize and understand, upon reading this description, that other and or different hook mechanisms and plug-socket mechanisms may be used to fulfill this assembling process. 
       FIG. 9  A-D show a detailed process of assembling latch bolt  118  into base cover  116 . Latch bolt  118  is positioned into base cover  116  from the front side of base cover  116  to the rear side of base cover  116  through latch bolt aperture  130 . This process can be viewed in three steps. First, part of latch bolt  118  is pushed into base cover  116  with latch assembly limit  202  out of base cover  116  (shown in  FIG. 9-B ). Second, latch bolt  118  is further pushed into base cover  116  with latch assembly limit  202  is pressed downward by latch bolt aperture beam  144  (shown in  FIG. 9-C ). Third, latch bolt  118  is still further pushed into base cover  116  with latch assembly limit  202  in base cover  116  (shown in  FIG. 9-D ). In step three, latch assembly limit  202  pops up when it clears latch bolt aperture beam  144 , and latch bolt aperture beam  144  confines latch assembly limit  202  and whereby confines latch bolt  118  in base cover  116 . With limit device such as latch assembly limit  202 , those skilled in the art will realize and understand, upon reading this description, that other and or different mechanisms may be used to fulfill this assembling process. 
       FIG. 10  A-B show a detailed process of mounting assembled top cover  212  to assembled base cover  210 . This process can be viewed in two steps. First, assembled top cover  212  is mounted an assembled base cover  210  with each one of upper plugs  160  fitting into a separate one of bottom slots  146  and with each one of upper hooks  162  being resisted by a separate one of bottom hooks  148 . This step leads to a so-called semi-assembly status. Second, assembled top cover  212  is further mounted on assembled base cover  210  with each one of upper plugs  160  fitting into a separate one of bottom slots  146  and also with each one of upper hooks  162  holding a separate one of bottom hooks  148 . This step leads to a so-called final-assembly status. In the semi-assembly status, assembled top cover  212  can be disassembled from assembled base cover  210  easily. In the final-assembly, assembled top cover  212  snaps on assembled base cover  210 , and it is relatively hard to disassemble the latch mechanism  100 . With a double mounting mechanism such as the one discussed above, those skilled in the art will realize and understand, upon reading this description, that other and or different mechanisms may be used to fulfill this double mounting process. 
       FIG. 11  shows the sliding track of trigger cap  114  on the arc side of top cover  112 . During the operation of trigger cap  114 , it slides along top cover meridian  220  to shift latch mechanism  100  between an extending (locked) position and a retracted (unlocked) position. Top cover meridian  220  is a curve whose projection on base surface  224  (shown in  FIG. 3 ) is straight line  222 . Straight line  222  parallels with the sliding orientation of latch bolt  118 .  FIG. 12  A-C show detailed circumstances of the locked position and unlocked position of latch mechanism  100 . Latch bolt  118  has a pair of latch bolt slots  204 , one of which has flexible tab  194 . The bottom part of flexible tab  194  is connected to latch bolt  118 . This gives flexible tab  194  resilience so that flexible tab  194  can define a variable room for one of latch bolt slots  204 . Long cap shaft  152  extends into one of the latch bolt slots  204  with flexible tab  194 . During the sliding process of trigger cap  114  from locked position and unlocked position, long cap shaft  152  is continuously pressed by flexible tab  194 . This improves preferable contact between trigger cap  114  and latch bolt  118 . With a flexible tab, those skilled in the art will realize and understand, upon reading this description, that other and or different mechanisms may be used to fulfill this curve sliding track and preferable contact. Since in the locked position, base stopping pin  180  (shown in  FIG. 5 ) and latch stopping pin  196  (shown in  FIG. 6 ) contacts with each other on their inclined surface, when a force is pushing trigger cap  114  toward front wall  134 , latch stopping pin  196  is able to pass the limitation of base stopping pin  180  if the force is larger than the resistant force from base stopping pin  180 . Therefore, latch bolt  118  can be actuated not only by actuator  120 , but also by trigger cap  114  manually. 
       FIG. 13  A-D show an acting process of latch mechanism  100 .  FIG. 13  A depicts a locked position of latch mechanism  100 . Latch bolt  118  extends out of housing  110  and is received by latch bolt receiver  125  on latch keeper  126 . Actuator  120  is in a retracted position and resisted by bevel wall  128  (shown in  FIG. 2 ) on latch keeper  126 . One embodiment of latch mechanism  100  is applied on a double hung window. In the locked position for a hung window, latch hook  149  (shown in  FIG. 2 ) is received by latch keeper socket  127  (shown in  FIG. 2 ).  FIG. 13  B depicts the action to an unlock position. By operating trigger cap  114 , latch bolt  118  retracts into housing  110  and is kept into this position by latch stopping pin  196  engaged with base stopping pin  180 . Before latch mechanism  100  moves away from latch keeper  126 , actuator  120  is still in the retracted position.  FIG. 13  C depicts the unlocked position. Latch bolt  118  is positioned in a position completely retracted in housing  110 . Actuator  120 , without limitation from bevel wall  128 , extends outwardly from housing  110  under the pressure of actuator spring  124  (shown in  FIG. 2 ).  FIG. 13  D depicts the action to the locked position. After actuator  120  contacts bevel wall  128  on latch keeper  126 , bevel wall  128  pushes actuator  120  into housing  110 . Actuator  120  actuates and unlocks latch bolt  118  when actuator  120  is pushed into housing  110 . Latch bolt  118  is unlocked by actuator  120  and extends out of housing  110  under the pressure of base spring  122  (shown in  FIG. 2 ). Latch bolt  118  is received by latch bolt receiver  125 . Latch mechanism  100  is in the locked position as before. 
       FIG. 14  A-E show a detailed actuating process. Contacting pin  174  of actuator  120  is moved along track P 1 -P 2 -P 3 -P 4  (shown in  FIG. 14  E). Track P 1 -P 2 -P 3 -P 4  is a closed curve. Those skilled in the art will realize and understand, upon reading this description, that other and or different tracks or curves may be used to fulfill this actuating process.  FIG. 14  A shows the actuating process in section P 1 , where actuator  120  is pressed by bevel wall  128  into housing  110  and latch bolt  118  is placed in the retracted position by operating trigger cap  114 . Latch bolt  118  is limited to this position by latch stopping pin  196  engaged with base stopping pin  180 . Contacting pin  174  is between base limit wall  188  and rear wall  138 . This is the circumstance shown in  FIG. 13  B.  FIG. 14  B shows the actuating process in section P 2 , where latch bolt  118  is kept in its retracted position and actuator  120  is extending outwardly from housing  110  under the pressure of actuator spring  124 . While actuator arm  170  moves forward, contacting pin  174  keeps touching base limit wall  188  and moves along base arc side  186 , and therefore, actuating pin  172  circumvents latch trigger pin  198  (shown in  FIG. 6 ). This is the circumstance shown in  FIG. 13  C.  FIG. 14  C shows the actuating process in section P 3 , where actuator  120  extends to a complete extending position. Contacting pin  174  passes base stud  184  and goes into harbor area  183  (shown in  FIG. 5 ).  FIG. 14  D shows the actuating process in section P 4 , where actuator  120  contacts bevel wall  128  on latch keeper  126  and bevel wall  128  pushes actuator  120  into housing  110  (also shown in  FIG. 13  D). During this process, contacting pin  174  slides backward along base chamfer  182 , wherein actuating pin  172  lifts latch trigger pin  198 , which disengages latch stopping pin  196  from base stopping pin  180 . Latch bolt  118 , without the limitation from base stopping pin  180 , extends outwardly from housing  110  under the pressure of base spring  122 . Base chamfer  182 , base stud  184 , base arc side  186 , and base limit wall  188  constitute a sliding ridge defining the sliding track (a closed curve) for contacting pin  174 . Those skilled in the art will realize and understand, upon reading this description, that other and or different sliding ridges may be used to fulfill this actuating process. Those skilled in the art will also realize and understand, upon reading this description, that other and or different mechanisms may be used to fulfill this actuating process. 
       FIG. 15  A-J show different embodiments with various trigger caps and screw holes. The latch mechanism disclosed here can be equipped with various trigger caps.  FIG. 15  B gives three exemplary trigger caps.  FIG. 15  C-D show the assembly of the latch mechanism with the first kind trigger cap.  FIG. 15  E-G show the assembly of the latch mechanism with the second kind trigger cap.  FIG. 15  H-J show the assembly of the latch mechanism with the third kind trigger cap. Those skilled in the art will also realize and understand, upon reading this description, that other and or different trigger caps may be used. 
     The latch mechanism disclosed here can be attached to sashes in various approaches with different screw locations. For example,  FIG. 15  H-J show one type of screw locations, where the screw holes are exposed on the housing of the latch mechanism.  FIG. 15  C-G show other types of screw locations, where the screw holes are on the base cover of the latch mechanism. These holes are hidden by the top cover and cannot be seen when the latch mechanism is assembled. 
       FIG. 15  A shows two different types of screw locations on the base cover. Multiple screw locations increase the adaptability of this latch mechanism to many window systems, including but not limited to, sliding window systems and double-hung window systems. Those skilled in the art will also realize and understand, upon reading this description, that other and or different screw locations may be used to adapt this latch mechanism to various window systems.