Abstract:
The present invention relates to a night latch in particular a night latch that includes a housing, tumbler, button, and a two resilient members. The housing of the present invention maintains the tumbler, button, and two resilient members. The housing also may have at least one protrusion located on its sidewall. The tumbler of the present invention has a pivoting member along with a means for housing a resilient member. In addition the tumbler of the present invention may have recess located on its front face. The tumbler also has at least one groove that co-acts with the protrusion on the sidewall. A first resilient member is used force the tumbler into an exposed position, and a second resilient member is used to keep the tumbler in a retracted position, via the co-action of the recess in the tumbler and a protrusion on the bottom portion of the button.

Description:
FIELD OF THE INVENTION 
   The present invention is directed to the field of window hardware, particularly window hardware for double hung windows. 
   BACKGROUND OF THE INVENTION 
   Double hung windows are a common type of window used in many homes and remodelings. There is a frame with a pair of tracks on each side of the frame. There is a top sash and a bottom sash. The top sash typically rides in the outer tracks, i.e. the tracks in the frame closest to the outside of a building. The lower sash rides in the inner track, i.e. that track that is closest to the interior of a house. The sash has a pair of vertical stiles that are joined to upper and lower horizontal styles. One or more panes of glass are retained in the sash. There can be an inner pane and an outer pane that extends from one vertical stile to the other and from one horizontal style to the other. There can be a third pane of glass positioned similarly with a gap between the first and second panes. The gap is usually filled with an inert gas such as argon. This structure provides a window with insulating qualities. One or more muntin bars can be present to provide a look of individual lights in the window of the type that are found in older construction. 
   In many double hung windows there is an issue of security. There is usually an outer screen that permits cooler air to ventilate into the house during the warmer months. In order to take advantage of the screen however, the bottom pane typically must be in a raised position. Double hung windows are usually provided with a sash lock that locks the lower and upper sash in position so that they cannot be opened from the outside. While this provides some security during the cooler months, the return of warm weather may make it difficult to use the sash lock in many instances. The sash lock has two positions, a locked position and an unlocked position. Thus the resident has a choice to either keep the window in a closed locked position or have the window sash unlocked and thus open to intruders. 
   In order to provide a means of ventilating a room yet provide some security, there have been a number of night latches and vent stops that have become available in the market. One such sash stop is U.S. Pat. No. 5,248,174 owned by Ashland Products. Another type of sash stop U.S. Pat. No. 4,923,230, owned by Ro Mai. These night latches or vent stops act in a similar fashion. The night latch or vent stop is placed in the face of the upper sash. Depending on the desired amount of ventilation, the night latch can be placed at any position on the face. Once the night latch is secured in the face of the window, the tumbler can be pressed in an inward and upward fashion activating a spring mechanism that will force the tumbler to an exposed position, thus creating the impeding force required to restrict movement of the lower window sash. Other prior art vent stops are U.S. Pat. Nos. 5,553,903 and 5,806,900 both of which are owned by Ashland. 
   As mentioned previously, the typical prior art vent stop prevented the opening of the lower sash in similar fashions. In the typical prior art the tumbler was held in a locked position via a catch portion located in the housing of the night latch. Thus, if inwardly and upwardly forces were applied perpendicularly to the face of the tumbler, these forces would free the tumbler from its locked, inactivated position, to its unlocked, activated position. 
   While the tumblers in the prior art night latches are capable of preventing the sliding member from moving passed a certain predetermined position, these tumblers have an unfavorable characteristic. That is in the prior art vent stop, in order for the user to free the tumbler from its inactivated position to its activated position or vice versa, the user must apply a multitude of forces in a variety of different angles. 
   Although the night latch and/or vent stops are capable of preventing the lower sash from moving passed a certain desired position, their utility is unfortunately outweighed by their inherent clumsy composition. The night latch in the present invention improves on the prior art shortcomings by implementing a unique method of activating and inactivating the tumbler from the housing, without taking away from its utility and its aesthetic quality. 
   OBJECTS OF THE INVENTION 
   It is an object of the present invention to provide a night latch that operates more easily than the prior art night latches. 
   It is an object of the present invention to provide an improved night latch that is more reliable in its operation than the prior night latches. 
   It is an object of the present invention to provide a night latch that allows the user to more readily reposition the tumbler back in an inactivated position. 
   It is still another object of the invention to allow the user the ability of activating the tumbler without the use of multiple forces to release the tumbler. 
   It is a still further object of the present invention to provide for a more durable night latch, so as to allow for a longer period of operability. 
   These and other objects of the present invention will become apparent to those skilled in the art from a review from the description provided below. 
   SUMMARY OF THE INVENTION 
   The present invention is an improved night latch or sash controlling mechanism. The improved night latch can be used with a variety of windows and doors, including but not limited to, single hung windows, double hung windows, sliding windows and doors, etc. The windows can be of the type that moves vertically or horizontally. If the windows are to move in a vertical fashion then the window will have upper and lower sashes situated in the frame of the window. If the windows are to move horizontally, then the windows will have right and left sashes situated in the window frame. A night latch for a sliding door can be installed and operated in the same manner as the sliding window, except the doors will sit in the door frame rather than a window frame. More specifically, this invention is directed to be an integral part of a sliding window or door, that is simple, inexpensive, and ergonomically superior to the prior art. 
   In the present invention the night latch has three primary components a tumbler, button, and a housing that will accommodate the tumbler and the button. The housing is placed in a groove or recess on the face of the upper window sash. The housing is constructed so as to make for a tight, smooth, and finished appearance when inserted into the groove of the window sash. This fit will make for an aesthetically pleasing appearance. 
   As in the prior art, a tumbler is generally used as the stopping mechanism in the night latch. In general, the tumblers are activated by applying an outside force in a multitude of ways directly to the tumbler, making for a rather difficult and sometimes impossible task. One example of this is when the spring inside the tumbler is new and rather tight. In the present invention the tumbler is activated via a separate button, located on the housing of the night latch. This allows the user to activate the tumbler with relative ease. The force applied can be in a downward motion, as in the present invention, or the force applied can be in an inward motion. The direction of the force applied depends on how the button is configured. 
   In addition to the relative ease of operation of the improved night latch. The improved night latch has an active cover located on the bottom of the housing, which allows for installing parts inside of the housing. In the prior art the housing is open, thus exposing the inside parts, such as the tumbler and spring, to the outside weathering elements, such as moisture in the air, which could cause malfunction of the night latch, i.e. rusty spring. In present invention the active cover acts as a barrier, so as to impede the destructive nature of weathering. 
   Furthermore, the night latch can be deactivated with even less effort than the prior art. If the user wished to close the night latch in the prior art, the user would have to exert an inward and downward force to deactivate the night latch. This is because the tumbler in the prior art is kept depressed via the face of the tumbler and the top plate of the housing. As mentioned previously application of these forces can prove to be rather burdensome when the night latch was fairly new. In the present improved night latch, the only force needed is a downward force, this is because of the coaction between the tensed bottom part of the button and the bottom protruding portion of the tumbler. The protruding portion of the tumbler serves a twofold function, first, it keeps the tumbler in a locked inactivated position, and second, when the button is depressed it keeps the tumbler in a locked activated position. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded view of night latch and stopping member frame; 
       FIG. 1(   a ) is a perspective view of the night latch of the present invention in place in a portion of a stopping member frame with tumbler exposed; 
       FIG. 2  is an exploded view of housing and tumbler of the present invention; 
       FIG. 2(   a ) is an exploded side view of the housing and tumbler of the present invention; 
       FIG. 3  is a rear end view of the night latch of the present invention with tumbler exposed; 
       FIG. 4  is a side view of night latch of present invention with tumbler exposed; 
       FIG. 5  is a side view of night latch of  FIG. 4  with tumbler exposed and side cover plate removed; 
       FIG. 6  is a perspective view of night latch of  FIG. 5  with cover plate removed; 
       FIG. 7  is a cross-sectional view of night latch of the present invention in place in a stopping member frame with tumbler depressed; 
       FIG. 8  is a cross-sectional view of night latch of the present invention in place in a stopping member frame with tumbler exposed; 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. 
   In  FIG. 1 , the night latch of the present invention is shown generally at  10 . The night latch  10  is shown positioned over slot  11  in stopping member  12 . The slot  11  is shown as having an oval shape, but any other suitable shape and size slots including but not limited to a square, rectangle, oval, etc. can be used depending on the shape of the latch. Preferably, however, the night latch  10  of the present invention will have a portion similarly shaped to the slot  11  as to present a clean appearance when placed in the stopping member  12 . In the present embodiment an oval shape, for illustration purposes was used. The stopping member can be a sash, doorframe, or any other member that has another piece sliding over it, where restriction of the sliding member is desired. The tumbler  36  can be in either a raised or lowered position. When raised it prevents movement of the door or sash 
     FIG. 2  is a more detailed view of the contemplated night latch. A housing  13  is generally defined by a first and second sidewall,  14  and  15  respectively, and a front and rear wall,  16  and  17  respectively. It is noted that the terms “front” and “rear” are used only for descriptive purposes and do not read on orientation of the device. Sidewalls  14  and  15  are preferably the same length, as are front and rear walls  16  and  17 , respectively, providing for a generally rectangular shape to housing  13 . Preferably, when in place within slot  11 , sidewalls  14  and  15  contact the edges of slot  11  to provide for a tight fit, and prevent a lateral movement of the night latch  10  within slot  11 . In addition, sidewall  14  or  15  can be detachable so as to act like a cover plate for accessing housing  13 . In the present embodiment sidewall  14  acts as a detachable cover plate too, as seen in  FIG. 2 . In another embodiment one may implement a separate cover plate that can be placed near the front end of housing  13 , as seen in  FIG. 2(   a ). 
   Front wall  16  can have a front flexible clip  18  and rear wall  17  can have a rear flexible clip  19 . Each clip can extend generally in an upward fashion, originating at or near bottom surface  20  of housing  13  and ending just below top plate  25 . In the present embodiment each clip creates a notch  22  between a lip  23  on bottom surface  24  of top plate  25 . When the night latch  10  is depressed into slot  11  on a stopping member  12 , each notch  22  can engage a portion of the stopping member  12 . This engagement can prevent vertical (front and back) movement of the night latch  10  within the stopping member  12 , as well as preventing the night latch  10  from being easily dislodged from slot  11 . 
   First sidewall  14  has an inner surface  26  and outer surface  27 . Second sidewall  15  has inner surface  28  and outer surface  29 . The inner surfaces  26  and  28  can have two protrusions  30  and  31  respectively that act as guide members for a tumbler  36 . This can be accomplished by setting protrusions  30  and  31  into cavity  32  located inside housing  13 . In addition to acting as guide members for tumbler  36  protrusions  30  and  31  acts as a limiting device for tumbler  36 , i.e. tumbler  36  will extend out only the distance allowed by the coaction between protrusions  30  and  31  and grooves  44 ( a ) and  44 ( b ) of tumbler  36 . The shape of the protrusions,  30  and  31 , can be of any suitable shape including but not limited to a square, rectangle, circle, etc. In the present embodiment protrusions  30  and  31 , and their respective grooves,  44 ( a ) and  44 ( b ) are of rectangular shape. Walls  14  and  15  also can have two circular areas,  33  and  34  respectively, positioned towards rear wall  17 . Circular areas  33  and  34  are aligned along the same central axis. These circular areas are designed so as to allow tumbler  36  to rotate from a recessed position to an outwardly position. The circular areas can be any circular areas known in the art, but not limited to an aperture, bore, cavity, etc. In the present embodiment circular areas,  33  and  34  are a bore and an aperture respectively. Bored area  33  on wall  14  can be enlarged so as to allow greater contact with axle  38 , this can be achieved by affixing a hollowed out extension of bored area  33  that surrounds a partial portion of outside perimeter of bored area  33 , not shown. As mentioned previously one can also have two apertures instead of one aperture and one bored hole, as seen in  FIG. 2 . 
   The lip  23  attached to top plate  25  is preferably at least the same size or larger and the same general shape as slot  11 . Thus, when night latch  10  is placed into slot  11 , lip  23  will contact at least the edges of slot  11 , or over spread the upper surface of the stopping member  12 . These dimensional attributes will allow for a tight fit that will exhibit a finished smooth exterior, which can be aesthetically pleasing. Although top plate  25  is referred to as a “plate”, it is understood that housing  13 , clip  18 , lip  23  and top plate  25  can be integral pieces, without any need for adhesives or assemblage. 
   A tumbler  36  is preferably designed to fit within cavity  32  of housing  13 . Tumbler  36  may have an upper surface  37 , which is preferably smooth and/or flat. A flat surface  37  will exhibit a more finished look for the night latch  10  when it is placed in stopping member  12 . Tumbler  36  can have a front end  43  and a rear end  42 , along with side surfaces  40  and  41 . In addition, tumbler  36  can have a rotation member  38  located on rear end  42  that extends from side surface  40  to side surface  41  on tumbler  36 . Rotation member  38  can fit into areas  33  and  34 . Rotation member  38  can be any suitable structure known in the art including but not limited to a peg, axle, pin, etc. Furthermore, rotation member  38  can be two separate members affixed to tumbler  36 , such as two cylindrical pegs attached to side surfaces  40  and  41  respectively. In the present embodiment rotation member  38  is single axle. In addition rotation member can be part of tumbler  36 , or rotation member  38  can stand alone. In the present embodiment rotation member  38  is a part of tumbler  36 . By setting rotation member  38  into corresponding areas,  33  and  34 , will act so as to allow tumbler  36  pivot within cavity  32 , and thus rotate from a recessed position to an extended position and have a portion exposed above the surface of stopping member frame  12 . 
   In addition to having rotation member  38 , tumbler  36  also has two arcuate grooves  44 ( a ) and  44 ( b ) located on side surfaces  40  and  41  respectively. Grooves  44  ( a ) and ( b ) can house guide members  30  and  31 , of sidewalls  14  and  15  respectively, and thus provide an arcuate path for tumbler  36  about axis of rotation member  38 . Furthermore, grooves  44  ( a ) and ( b ) and guide members  30  and  31  can act as a restricting device for tumbler  36 , as mentioned previously. When tumbler  36  is in an activated position guide members  30  and  31  contact the bottoms of  45  ( a ) and ( b ) of grooves  44  ( a ) and ( b ), this interaction will lock guide members  30 ,  31 , and bottoms  45  ( a ) and ( b ), which will cause tumbler  36  to lock into an exposed position, thus exposing the stopping surface  52 , which will act as to prevent the sliding member from moving beyond a certain predetermined position. 
   Tumbler  36  has a bored area  100 , which can be placed on either side of tumbler  36 , as seen in  FIG. 5 . In the present embodiment bored area  100  is located toward the rear end of side surface  40  of tumbler  36 . Bored area  100  has a wall  10 , not shown, that extends tangentially from plane  102 , not shown, to side surface  40 . In addition, bored area  100  has a circular shaped protrusion; any circular shaped protrusion known in art can be implemented but not limited to a peg, pin, etc. In the present embodiment a cylindrical peg  103  that extends tangentially the exact distance of wall  101  was implemented. 
   The force that causes tumbler  36  to rotate in an outwardly fashion, can be created by a spring. Any spring known in the art, but not limited to coil, helical, torsional, etc. can be used. In the present embodiment, a coil spring  46  was implemented. Spring  46  has three members; the first is a coiled portion  50  that rests on cylindrical peg  103 . The second member is elongated portion  48 , which exerts a constant force on the inside bottom surface  20  of housing  13  and a third member, elongated portion  49 , which exerts a constant force on wall  101  in bored area  100  of tumbler  36 . The tension created by elongated portions  48  and  49  is of such a nature that the tension will be greater when tumbler  36  is depressed so as to push tumbler  36  in an outwardly fashion when button  54  is triggered. 
   Front end  43  can have a stopping surface  52 . When exposed stopping surface  52  will prevent movement of a sliding frame or member intending to slide over night latch  10 . Stopping surface  52  can also have a cavity portion  53 , which is a hollowed portion of front end  43  of tumbler  36 . Cavity  53  is of such dimensions so as to allow entry of protruding portion of button  54 . In addition, cavity  53  should be of such dimensions so that the integrity of tumbler  36  will not be compromised by the frequent contact of a sliding member 
   The release of tumbler  36  from housing  13  can be controlled by an interaction between a button  54  and a spring-loaded release member  55 . Button  54  can have a top surface  56  which can be in the same plane as upper surface  37  of tumbler  36 . Button  54  can reside in opening  35  of top plate  25 . Top surface  56  of button  54  can be designed to have the same shape as opening  35  of top plate  25 , however, any suitable shape known in the art, but not limited to square, rectangle, circle, or any combination thereof. In the present embodiment, because of the rectangular look of the night latch  10 , opening  35  has a rectangular rear section and circular front tip portion. The top surface  56  of button  54  has the same basic look as opening  35 , except that top surface  56  is smaller in proportion, so as to allow movement inside opening  35 . Here, the user can access the button  54  easily. Top surface  56  of button  54  can have a groove  57 , which the user can engage with a finger, fingernail, pen, pencil, etc. or any other suitable instrument known in the art. Button  54  can be designed to move in different ways, any suitable movement known in the art but not limited to sliding, depression, etc. In the present embodiment button  54  was designed to slide in a up and down manner, within opening  35 . When the night latch is not activated, i.e. tumbler  34  is depressed; the top surface  56  of button  54  will rest toward the rear end  58  of opening  35  of to plate  25 . When the user wishes to activate night latch  10 , the user will apply a downward force to groove  57 , which will cause the top button  56  to slide toward the front end  59  of opening  35 . 
   When button  54  is moved toward the front end  59  of opening  35 , a release member  55 , attached to bottom tooth  55 ( a ) of top surface  56  moves in the same direction. Release member  55  can be of any suitable construction known in the art. In the present embodiment release member  55  can best be described as having a rectangular top portion  60 , engaged with the bottom tooth  55 ( a ) of top surface  56 . Rectangular portion  60  can be solid or hollow. In the present embodiment portion  60  is hollow so as to house tooth  55 ( a ) of button  54 . In addition rectangular portion  60  can have two wings  63  and  64  on both side surfaces  61  and  62  respectively. Wings  63  and  64  can be of any suitable shape known in the art including but not limited to a square, rectangle, oblong, etc. In the present embodiment two oblong wings were implemented. Wings  63  and  64  are allowed to move in a linear back and forth manner, inside slots  68  and  69  respectively, not shown, which are located on sidewalls  14  and  15  respectively. Slots  68  and  69  can be of any suitable shape known in the art including but not limited to square, rectangle, oblong, etc. In the present embodiment two rectangular slots were implemented. 
   In addition to having a top rectangular portion  60 , release portion  55  has another portion  70  that runs from the back of portion  60  toward the bottom of housing  13 , as seen in  FIGS. 2 and 6 . Portion  70  can best be described as a arm with a tooth like protrusion  71 , located in it&#39;s upper top surface  72 , for engaging tumbler cavity  53 , and a circular protrusion  73  located on it&#39;s front bottom surface  74 , located below rectangular portion  60 , facing front of night latch  10 , used for housing spring  75 , as seen in  FIGS. 2 and 5 . Any suitable shape known in the art can be used for tooth like protrusion  71  and circular protrusion  73 . In the present embodiment a triangular shaped tooth was used for protrusion  71  and a cylindrical shaped peg was used for protrusion  73 . Spring  75  can be any suitable spring known in the art but not limited to a coil, leaf, torsional, etc. In the present embodiment a torsional spring was implemented. Spring  75  sits over peg  73 , between front surface  74  and back surface  76  of front wall  16 . Spring  75  will exert a constant force on front bottom surface  74  of button  54  so as to cause button  54  to want to accelerate toward rear end  58  of opening  35  of top plate  25 , thus engaging tooth like protrusion  71  into tumbler&#39;s  36  cavity  53 . It is this constant force that keeps tumbler  36  in a depressed state. 
   On bottom surface  20  of housing  13  there exists a ramp like protrusion  77  with an aperture  78  at its highest point, as seen in  FIGS. 7 and 8 . Protrusion  77  can serve two functions. Protrusion  77  can provide added stopping power for button  54  when tumbler  36  is activated, thus preventing the force of spring  75  from rotating button  54  out of opening  35  of top plate  25 . Furthermore, aperture  78  of protrusion  77  acts as a housing for one of cover plate  14 &#39;s pins,  79 . Pins  79  and pin  80  are located on the bottom of inside surface  26  and the top rear end of inside surface  26  respectively. When access to the inside of housing  13  is needed, cover plate  14  can be snapped out of place. When access to inside of housing  13  is no longer required cover plate  14  can be snapped back into place by inserting pin  79  into aperture  78  of protrusion  77 , and inserting pin  80  into aperture  81 , located on the upper side wall  82  of housing  13 , thus closing housing  13 . 
   In another embodiment one may have the tumbler with a protrusion and the arm of the release member with a recess. The functionality of the vent stop would not be altered with this type of embodiment. 
   When the user desires to activate tumbler  36  so as to cease movement of sliding window member, the user will exert a downward force, greater than that of spring  75 , on groove  57 , of button  54 . This force will cause button  54  to move in a direction opposite that of the stored potential energy of spring  75 , thus causing release portion  55  of button  54  to disengage cavity  53  of tumbler  36 . When tumbler  36  is free to pivot on the axle  38 , the upward force of spring  46  will cause tumbler  36  to rotate in an outwardly direction until rectangular guides  30  and  31  meet with bottoms  45 ( a ) and  45 ( b ) of grooves  44 ( a ) and  44 ( b ), at which time stopping surface  53  of tumbler  36  will be exposed, thus preventing sliding window member from opening any further. 
   As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense. In the view above it will be seen that several objects of the invention are achieved and other advantageous results attained.