Patent Abstract:
A window latch assembly for locking first and second windows together includes a cover member coupled to the first window, and a handle pivotably coupled to the cover member. A lock member is fixedly coupled to the handle and has a lock portion adapted to protrude beyond a planar extent of the cover into a locked position, wherein the lock portion engages a lock keeper coupled to the second window, and an unlocked position, wherein the lock keeper is retracted inside the cover member. A mechanical finger is movable between a first position allowing the lock portion to be moved from the unlocked position to the locked position, and a second position preventing the lock portion from being moved from the unlocked position to the locked position, thereby preventing damage of the first and second windows.

Full Description:
BACKGROUND OF THE PRESENT INVENTION  
       [0001]     The present invention relates to a lock mechanism for use within a window assembly, and in particular to a lock mechanism that prevents accidental damage to the window assembly during operation thereof.  
         [0002]     Window assemblies and lock mechanisms for securing window assemblies, particularly single and double hung window sash assemblies, are used frequently in residential and commercial building structures. These lock mechanisms frequently include a deployable catch member that is operative between an engaged position and a disengaged position. The disengaged position allows a window assembly to be opened. The engaged position prohibits opening of the window assembly because the catch member is inserted into a lock keeper.  
         [0003]     A commonly acknowledged shortcoming in the currently available designs of single and double hung window sash lock mechanisms is that the catch member can be rotated to the locked position when the sash are in an opened position. Specifically, former designs have allowed the catch member to be rotated to the locked position when the sash are in an opened position. When this occurs, the catch member extends outwardly from the associated sash and into the path of the remaining sash thereby causing damage to the remaining sash, lock, lock keeper, etc. when the sash are moved to the closed position.  
         [0004]     Accordingly, a lock mechanism that prevents the catch member from moving into the locked position when the window assembly is open would be useful and an improvement in the art.  
       SUMMARY OF THE INVENTION  
       [0005]     In one aspect of the present invention, a window latch includes a housing member having an interior and a handle operably coupled to the housing member wherein the handle is movable between an unlocked position and a locked position. A catch member is fixed for rotation with the handle and includes a first stop. The catch member rotates between a locked position corresponding to the locked position of the handle, wherein the catch member is adapted to engage a lock keeper thereby preventing movement of a first window with respect to a second window, and an unlocked position, corresponding to the unlocked position of the handle wherein the catch member is adapted to disengage a lock keeper, thereby allowing movement of the first window with respect to the second window. A lever is operably coupled to the housing and includes a second stop. The lever operates between a first position, wherein the second stop abuts the first stop preventing rotation of the catch member from the unlocked position to the locked position, and a second position, wherein the lever allows rotation of the catch member from the unlocked position to the locked position. The second stop is configured to allow rotation of the catch member from the locked position to the unlocked position when the lever is in the first position and when the lever is in the second position.  
         [0006]     In another aspect of the present invention, a window assembly includes a first window including a first window sash and a second window that includes a second window sash substantially parallel with and movable relative to the first window sash. A lock mechanism is fixed to a select one of the first window sash and the second window sash, and a lock receiver is fixed to a select one of the first window sash and the second window sash not fixed to the lock mechanism. The lock mechanism includes a lock member operating between a locked position, wherein the lock member engages the lock receiver preventing movement between the first and second windows, and an unlocked position allowing movement between the first and second windows. A bar member moves between a first position, wherein the bar member engages the lock mechanism preventing the lock mechanism from being moved from the unlocked position to the locked position, and a second position allowing the lock mechanism to be moved from the unlocked to the locked position.  
         [0007]     In yet another aspect of the present invention, a window latch assembly includes a cover member and a handle pivotably coupled to the cover member. A lock member is fixed for rotation with the handle and has a lock portion adapted to protrude beyond a planar extent of the cover into a first position and retract inside the cover into a second position. The lock keeper is also adapted to securely engage a complementary lock keeper. A mechanical finger is movable between a first position allowing the lock portion to be moved from the second position to the first position, and a second position preventing the lock portion from being moved from the second position to the first position.  
         [0008]     The present inventive window latch comprises an uncomplicated design, is quickly and easily assembled during manufacture, is relatively economical to manufacture, is capable of a long operating life, and is well adapted for the proposed use. Specifically, the window latch allows normal operation of a window assembly while preventing accidental damage to the components thereof by an outwardly extended catch or lock member.  
         [0009]     These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  is a front elevational view of a window assembly embodying the present invention;  
         [0011]      FIG. 2  is an enlarged, exploded, top and side perspective view of a window latch;  
         [0012]      FIG. 2A  is a top and side perspective view of the window latch in an unlocked position;  
         [0013]      FIG. 2B  is a top and side perspective view of the window latch in a locked position;  
         [0014]      FIG. 3  is a side elevational view of the window latch in the locked position;  
         [0015]      FIG. 4  is a front elevational view of the window latch including a raised lever;  
         [0016]      FIG. 5  is a top and opposite side perspective view of the window latch;  
         [0017]      FIG. 6  is a cross-sectional view of the window latch taken at line VI-VI,  FIG. 5 ;  
         [0018]      FIG. 7  is a top and opposite side perspective view of the window latch including a raised lever; and  
         [0019]      FIG. 8  is a cross-sectional view of the window latch taken at line VIII-VIII,  FIG. 7 . 
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0020]     For purposes of description herein the terms “upper”, “lower”, “right”, “left”, “rear”, “front”, “vertical”, “horizontal” and derivatives thereof shall relate to the invention as oriented in  FIG. 2 . However, it is to be understood that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.  
         [0021]     The reference numeral  10  ( FIG. 1 ) generally designates a window assembly embodying the present invention, which is designed for use in a building structure (not shown). The window assembly  10  has a window latch  12  ( FIGS. 2 and 3 ) that includes a housing member  14  having an interior  16  and a handle  18  pivotably coupled to the housing member  14  wherein the handle  18  is movable between a locked position  19  ( FIG. 2B ) and an unlocked position  20  ( FIG. 2A ). A catch member  22  is fixedly coupled with the handle  18  and includes a first stop  24 . The catch member  22  rotates between a locked position  19   a  corresponding to the locked position  19  of the handle  18  and wherein the catch member  22  is adapted to engage a lock keeper  25  thereby preventing movement of a first window  26  with respect to a second window  28 , and an unlocked position  20   a,  corresponding to the unlocked position  20  of the handle  18  and wherein the catch member  22  is adapted to disengage the lock keeper  25 , thereby allowing movement of the first window  26  with respect to the second window  28 . A lever  30  is pivotably coupled to the housing member  14  and includes a second stop  32 . The lever  30  operates between a first position  31 , wherein the second stop  32  abuts the first stop  24  preventing rotation of the catch member  22  from the unlocked position  20   a  to the locked position  19   a,  and a second position  33 , wherein the lever  30  allows rotation of the catch member  22  from the unlocked position  20   a  to the locked position  19   a,  and wherein the second stop  32  is configured to allow rotation of the catch member  22  from the locked position  19   a  to the unlocked position  20   a  when the lever  30  is in the first position  31  and when the lever  30  is in the second position  33 .  
         [0022]     In the illustrated example, the catch member  22  is secured to a top portion  34  of the second window  28  and adapted to engage the lock keeper  25  secured to a bottom portion  36  of the first window  26 . Alternatively, the catch member  22  may be secured to the bottom portion  36  of the first window  26  such that it engages the lock keeper  25  secured to the top portion  34  of the second window  28 .  
         [0023]     As best illustrated in  FIGS. 2, 2A , and  2 B, the handle  18  rotates on a top surface  38  of the housing member  14  causing rotation of the catch member  22  into and out of the locked and unlocked positions  19   a,    20   a.  Specifically, an aperture  40  extends through a center portion  42  of the catch member  22  and receives a pivot rod  43  therein that is secured to the handle  18 , thereby coupling the handle  18  for rotation with the catch member  22 .  
         [0024]     The catch member  22  includes an indent  44  located adjacent to a retaining flange  46 . The first stop  24  is disposed on an open side  48  of the catch member  22  opposite from the retaining flange  46 . The arcuately shaped retaining flange  46  slopes upwardly between opposite ends  47 ,  49  thereof.  
         [0025]     The lever  30  is located within the interior  16  of the housing  14  adjacent to the catch member  22  and pivots about a pivot axis  50  as defined by a pair of pivot bosses  53 . The lever  30  is rotatable between the first position  31  and the second position  33  in a plane perpendicular to a plane in which the handle  18  rotates. When the lever  30  is in the first position, the second stop  32  abuts the first stop  24 . A distal end  52  of the lever  30  is rotated upward into the second position  33  when the window assembly  10  is opened, as further explained below. Rotation of the lever  30  moves the second stop  32  out of interference with the first stop  24 , thereby allowing the handle  18  to rotate the catch member  22 . In the illustrated example, the handle  18  generally turns approximately 180 degrees in the direction of arrow  55  into the locked position  19  and in the direction of arrow  56  in the unlocked position  20 .  
         [0026]     In the event that the lever  30  is moved to the first position  31  when the catch member  22  is in the locked position  19   a,  the handle  18  and catch member  22  may be rotated to raise the lever  30  into the second position  33 . As illustrated, a biasing force is exerted on the lever  30  by a spring member  57  forcing the lever  30  towards the first position  31 . Alternatively, the force exerted on the lever  30  may be a gravitational force, or a combination of the gravitational force and the spring force. During rotation of the catch member  22 , the first stop  24  contacts an angled back portion  58  of the second stop  32  of the lever  30 . When a force applied by a user on the handle  18  is greater than the force from the spring member  57 , the angled back portion  58  of the second stop  32  and the entire lever  30  is raised until the first stop  24  clears an abutting face  60  of the second stop  32 . The first stop  24  is no longer in contact with the angled back portion  58  of the second stop  32  once the first stop  24  clears the abutting face  60  of the second stop  32 , thereby allowing the spring member  57  to force the lever  30  back to the first position  31 . Accordingly, the catch member  22  cannot rotate from the unlocked position  20   a  to the locked position  19   a  because the abutting face  60  of the second stop  32  is in interference with the first stop  24 .  
         [0027]     In operation, the catch member  22  ( FIG. 3 ) rotates out of the housing member  14  to engage the lock keeper  25 . The retaining flange  46  of the catch member  22  secures a complementary receiver  62  in the lock keeper  25 . The handle  18  and the catch member  22  are prevented from rotating further once the retaining flange  46  is fully secured in the lock keeper  25 .  
         [0028]     The catch member  22  of the window latch  12 , as illustrated in  FIG. 4 , is in the unlocked position  20   a  with the lever  30  in the second position  33 . The catch member  22  is positioned inside the housing member  14  and above a planar extent of a bottom portion  64  of the window latch  12 . The catch member  22  is secured to the pivot rod  43  which is received by a sleeve  66  of the catch member  22 . A collar  68  is disposed around the pivot rod  43 , between the top surface  38  of the housing member  14  and the handle  18 . A frictional washer  69  disposed below the collar  68  creates frictional resistance that impedes movement of the handle  18  out of the unlocked position  20  and out of the locked position  19 . This frictional resistance minimizes the likelihood that the handle  18  will rotate the pivot rod  43  in the sleeve  66  without force applied by a user.  
         [0029]     The catch member  22  of the window latch  12 , as illustrated in  FIGS. 5 and 6 , is in the unlocked position  20   a  with the lever  30  in the first position  31 . The window latch  12  will generally have this arrangement when the lock keeper  25  is not adjacent to the housing member  14 , i.e., when the window assembly  10  is open. Further, in this position, the first stop  24  is aligned with the second stop  32  and prevents rotation of the handle  18 . The distal end  52  of the lever  30  protrudes beyond a vertical planar extent  70  of the housing member  14  when the lever  30  is in the first position  31 . The lock keeper  25  abuts the distal end  52  of the lever  30  forcing the lever  30  to pivot upward about the pivot axis  50  disposed on the inside portion of the housing member  14  when the window assembly  10  is closed by a user.  
         [0030]     The catch member  22  of the window latch  12 , as illustrated in  FIGS. 7 and 8 , is in the unlocked position  20   a  with the lever  30  in the second position  33 . The window latch  12  will generally have this arrangement when the lock keeper  25  is adjacent to the window latch  12 , i.e., when the window assembly  10  is closed. In this position, the second stop  32  has been rotated vertically out of interference with the first stop  24 , thereby allowing rotation of the catch member  22 . The distal end  52  of the lever  30  does not protrude beyond the vertical planar extent  70  of the housing member  14  when the lever  30  is in the second position  33 .  
         [0031]     The above description is considered that of the preferred embodiments only. Modifications of the invention will occur to those skilled in the art and to those who make or use the invention. Therefore, it is understood that the embodiments shown in the drawings and described above is merely for illustrative purposes and not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the Doctrine of Equivalents.

Technology Classification (CPC): 4