Abstract:
A sash lock having an extruded housing is disclosed. The housing has two open sidewalls. The housing receives a frame, the frame is securable to the underside of the housing. The frame has a sidewall member that forms the sidewall of the housing.

Description:
FIELD OF THE INVENTION  
       [0001]    The present invention is directed to improvements in the method of manufacture of sash locks and the sash locks so manufactured. More particularly, the present invention is directed to sash locks manufactured in part by an extrusion process. The present invention also is directed to sash locks that can be made from more than one material, particularly the housing. 
       BACKGROUND OF THE INVENTION  
       [0002]    Sash locks are commonly used on a pair of sliding windows or on some tilt windows. The sash lock typically has a housing with a handle that rotates a cam or tongue from a first position to a second position. One of the positions is usually a recessed position and the other is an extended or locked position. The tongue or cam usually controls a keeper although sometimes, the tongue extends sufficiently that the keeper is not necessary to prevent movement of one or both of the sashes in a window. 
         [0003]    Sash locks are usually made by a casting process where molten metal or plastic is poured into a mold. Once the material has cooled, the casting can be removed for machining of burrs and polishing if desired. Metal casting is a time consuming process because it can take some time for the metal to cool in the mold. Also, casting is expensive because many expensive molds are required to manufacture large quantities of product. As a result, there is a need for an improved process for making sash locks. 
       OBJECTS OF THE INVENTION  
       [0004]    It is an object of the present invention to provide an improved process for manufacturing sash locks. 
         [0005]    It is also an object of the invention to provide an extrusion housing for a sash lock. 
         [0006]    It is another object of the invention to provide an extrusion process for manufacturing sash lock covers. 
         [0007]    It is a further object of the invention to provide a unique design for a sash lock. 
         [0008]    It is still another object of the present invention to provide a lower cost sash lock. 
         [0009]    It is a still further object of the present invention to provide an improved composite lock. 
       SUMMARY OF THE INVENTION  
       [0010]    The present invention is directed to a sash lock that has an outer cover and a separate sidewall. In a preferred embodiment there is an extruded cover and a separate housing. The cover is formed by passing a molten material such as plastic or metal through a die to form a length of extrudate. This length of extrudate has a top surface, a bottom surface and a pair of end surfaces or end walls. Depending on the shape of the die, the extrudate can have a variety of configurations. In one embodiment, the extrudate can have a curved top surface where there are no distinct or separate end walls. Alternatively, the end walls may extend generally at right or other angles to a relatively flat top surface for the extrudate. It will be appreciated that any number of combinations for the configuration of the extrudate are possible. 
         [0011]    Once the extrudate is cooled, it is cut generally at right angles to the direction of travel of the extrudate from the die to form a plurality of covers. The resultant cover has a top surface, a bottom surface and usually a pair of end walls or end surfaces. There are no sidewalls in the extruded cover that extend from one end wall to the other end wall and which extend downward from the top surface. 
         [0012]    The cover will have one or more, usually three, orifices drilled therein. Two of these orifices typically adjacent to the end walls are for screws or other means to pass through and secure the cover to a sash. The third orifice is for a handle mechanism or operating mechanism that includes a handle, a stem and a cam or tongue. The handle is on the outer surface of the cover. The stem extends from the handle through the cover where it is secured to the cam or tongue. As the handle is rotated, the tongue or cam moves from a first position to a second position. One of the positions is a recessed or unlocked position. The other position is an extended position or a locking position. 
         [0013]    Because some customers may object to the open sidewalls of the extruded cover, the sash lock may also include a wall member that seals one of the open sidewalls of the sash lock. The opposite sidewall remains open so that the cam or tongue may extend to a locking position. In a preferred embodiment there is a frame that is secured to the underside of the housing or extruded cover. The frame may be made of any suitable material. However, in order to save costs the frame is preferably made of a plastic material or a relatively inexpensive metal. The frame has a body portion and a side wall portion. The sidewall portion preferably has a shape that conforms to the sidewall profile of the cover, i.e. that portion under the top surface and between the two end walls or end surfaces. This sidewall portion forms a sidewall on one side of the cover. The other sidewall is open to permit the tongue or cam to pass through to lock the window. 
         [0014]    The body preferably snaps into the underside of the cover or it can be secured to the cover by means of two orifices which line up to the orifices in the cover for securing the cover to a sash. When the cover is secured to the sash by means of a screw, for example, the screw passes through one or more of the orifices in the body and secures the frame in place. 
         [0015]    The cover may be sized so that it extends over a keeper and provides a smooth finish to the surface of the lock and keeper in combination. Alternatively, there is a visually separate sash and keeper. In this second embodiment the sash lock does not have a hood covering the keeper. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0016]      FIG. 1  is a top view of the sash lock of the present invention with a keeper. 
           [0017]      FIG. 2  is a top view of the sash lock of the present invention with the tongue or cam extended. 
           [0018]      FIG. 3  is an underside view of the sash lock and keeper of  FIG. 1 . 
           [0019]      FIG. 4  is an underside view of the sash lock and keeper of  FIG. 2 . 
           [0020]      FIG. 5  is a side view of the sash lock of  FIG. 1  showing the side wall portion of the frame. 
           [0021]      FIG. 6  is a side view of the sash lock of  FIG. 5  with the lock in an open position. 
           [0022]      FIG. 7  is a side view of the sash lock of  FIG. 5  with the sash lock in a locked position. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0023]    In the present invention there is a cover or housing for a sash lock with open sidewalls that are transverse to the end edges of the cover. At least one of the sidewalls is open to permit a tongue or a portion of a cam to extend outwardly to an extended or locking position. The cover of the present invention may be made by any suitable means. One preferred means of manufacture is by an extrusion process. 
         [0024]    A metal or a polymeric material is heated to its melting temperature and is processed in an extruder where it is forced through a die. The die may be any suitable shape for producing an extrudate, preferably a linear extrudate. The shape of the extrudate as it is forced from the die may be curved, generally C shaped or any other suitable shape. There can be any number of decorative designs extruded through the die. Another shape may be a three sided die with a top surface and two end surfaces. The end surfaces may be generally perpendicular to the top surface of the housing or at an angle thereto. It will be appreciated that the shape can vary as desired. 
         [0025]    When the molten material passes through the die, it may be cooled by a suitable spray of oil or water. Alternatively, the extrudate may pass through a bath where it is cooled. The extrudate when it comes out of the die has a lengthy top surface. Depending on the shape of the die chosen, the extrudate may have a pair of end walls extending on opposite sides of the top surface. The end walls may extend downwardly from the top surface. The extrudate is cut from one end wall to the opposite end wall to form a plurality of covers. These covers can have a width from one sidewall to the other sidewall that can vary as desired. The covers  11  may have a top surface  12 , a bottom surface  13  and a pair of end edges or end walls  14  and  15 . The cover or housing has a first side edge and a second side edge on opposite sides of the cover and extending from one end edge to the other. There is no sidewall extending from one end edge or end wall  14  to the opposite end edge or end wall  15 . Thus, the cover  11  presents a structure that is open on the two sides. On the top surface  12 , there are one or more orifices  16  to  18  present that extend through the top surface  12  to the bottom surface  13 . One of these orifices is for the locking mechanism  19 . The locking mechanism  19  has a handle  20  that is rotatable from a first position  21  to a second position  22 . The handle  20  has a contact surface  23  which the user touches, as well as an arm  24  extending therefrom to a base. Connected to the underside of the base is a stem  25 . The stem  25  passes from the handle  20  through the hole or opening  16  in the cover  11  where it is secured to a cam or a tongue  26  under the cover  11 . The tongue or cam  26  has a surface that contacts the second sash (not shown) or a keeper  32  on the second sash and prevents either a first sash or a second sash from moving. The other holes  17  and  18 , usually two, are present for securing the sash lock cover to a sash. The handle has at least two positions. There is a first position where the tongue or cam is in a recessed or unlocked position. The second position is a locked or extended position. When the cam or tongue is in an extended position, the tongue or cam may contact a keeper, if desired, to lock the sashes. Alternatively, the tongue can extend over the surface of a sash and prevent the sash from moving, thus providing a locking feature. 
         [0026]    The sash lock  10  also has a separate frame  27 . The frame  27  is inserted into the underside of the cover or housing. The frame  27  has a body  28  which has a sidewall  29 , generally perpendicular to the body  28 . The sidewall  29  forms the sidewall in the sash lock  10  and is positioned with respect to the cover  11  at one side edge of the top surface  12  and extending from one edge  14 A of the top surface  12  to the opposite edge  1   5 A. The opposite side of the cover remains open to permit the cam or tongue  26  to pass through when the tongue or cam is moved to a locking position. The body  28  of the frame is preferably a generally flat member typically extending from the region of one end edge or end wall of the cover to the other end or end wall of the cover. The body may also be comprised of a framework  30  as well, as seen in  FIGS. 3 and 4 . This framework has a first member  31  that extends generally from one end of the cover to the opposite end. The first member  31  has two side members  33  and  34  extending generally perpendicular thereto to which secure the sidewall  29  to the frame  27 . Each of the side members  33  and  34  are provided with an orifice  16  and  17  which lines up with the openings  16  and  17  in the cover  11  to secure the cover  11  and frame  27  to a sash. The frame  27  in a preferred embodiment may also be snapped into the cover  11 , thus eliminating the necessity of orifices in the frame. 
         [0027]    The size of the cover may vary. In the figures, the cover is sized to go over any keeper that is present. If a shorter cover is used, then the cover need not hide the keeper.