Abstract:
A latch wherein latching and unlatching is accomplished by an inward push by the keeper into the latch housing. The latch uses an improved housing configuration in conjunction with improved internal components, allowing for more consistent and reliable operation.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention is a latch wherein latching and unlatching are accomplished by an inward push of a keeper into the latch housing. 
     2. Description of the Related Art 
     Although push-push latches have been proposed in the art, none are seen to provide the positive and reliable operation of the push-push latch of the present invention. 
     An example of a known push-push latch is described in U.S. Pat. No. 4,655,489 issued to Robert Bisbing on Apr. 7, 1987. The push-push latch of Bisbing uses a spring having a portion under compression and a portion in tension. The Bisbing latch is difficult to assemble and requires one side of the latch housing to be removable for assembly. The simplified design of the present invention allows the use of a one piece housing which reduces manufacturing cost. 
     SUMMARY OF THE INVENTION 
     The present invention is a latch wherein latching and unlatching are controlled by an inward push by the keeper towards the latch, generally known as a push-push latch. 
     The latch includes a housing, containing a hook beam, a shuttle opposite the hook beam, and a compression spring, for biasing the shuttle upward within the housing. The latch mates with a corresponding keeper to secure a moving member, such as a door or drawer, to a nonmoving member, such as the frame of the door or drawer. The latch will typically be secured to the nonmoving member, with the keeper secured to the moving member, but the opposite arrangement will work equally well. It should be noted that the following summary refers to a top, bottom, left, right, etc. for simplicity of reference only, and not to imply that the orientation of the latch is critical to its function. 
     The housing is generally rectangular, and is preferably made of one-piece construction. The housing is in the form of a shell defining a cavity having an interior, and an opening in its top surface. The housing has a pair of opposing openings in its front and back surfaces. A pair of opposing snap legs extends downward and inward into the housing from the top edges of the opposing openings. A second pair of opposing snap legs extends upward and outward from the bottom of the housing&#39;s left and right sides, ending with a ridged surface. The front of the housing further has an additional opening on the same side of the housing as the hook beam. A resilient finger extends from the bottom edge of the opening upward and slightly inward. The bottom of the housing also has a ramp located at the bottom rear corner of the interior below the shuttle of the latch and to one side of the spring. The ramp forms an inclined plane which slants upward in back of the spring and shuttle of the latch. 
     The hook beam is located within the housing, extending from the top opening towards the bottom of the housing. The hook beam includes a top hook for engaging the keeper, described below. The hook includes a flange extending to one side. A small detent boss projects from the side of the hook opposite the flange. The hook beam also includes a stem. The stem includes a central projection which extends outward towards the shuttle and which preferably has a flat top side. The bottom end of the hook beam further includes a pivot, which is preferably a pair of bosses projecting from either side of the bottom end of the hook beam. The pivot bosses of the hook beam are positioned between the inner snap legs and the bottom of the front and back openings. The motion of the bottom end of the hook beam is rather complex. The pivot bosses are constrained within the front and rear openings in the housing. The front and rear openings are elongated and allow the bottom end of the hook beam to translate to the left or right, as well as for the hook beam to pivot about the central axis of the bosses. The left end of the front and rear openings is notched which additionally allows the pivot end of the beam to move up and down when the pivot bosses are positioned at the left end of the front and rear openings. The bottom end of the hook beam also includes a projection, which projects approximately perpendicularly to the left of the hook beam. The projection preferably has a hook shape. 
     The shuttle is located opposite the top hook. The bottom portion of the shuttle defines a channel for guiding the compression spring, which abuts the bottom of the housing. The top of the shuttle includes a top surface for making contact with the keeper (described later). The top of the shuttle further includes an overhang for making contact with the top side of the central projection of the hook beam. An arm extends outward from one side of the top of the shuttle in the same direction as the overhang, immediately below the flange extending from the hook beam&#39;s hook. A skirt extends downward and to the right from the top portion of the shuttle, being dimensioned and configured to push against the perpendicular projection at the bottom of the hook beam, when the hook beam is in the unlatched configuration. 
     The keeper includes a mounting plate, preferably having an adhesive backing, and a hook. The keeper&#39;s hook is dimensioned and configured to push downward on the shuttle&#39;s top portion, and to engage the hook beam&#39;s top hook. 
     The latch will typically be installed within a socket. The socket is shaped to correspond with the shape of the housing, to prevent misalignment of the latch. Upon inserting the latch into the socket, the ridges on the outer snap legs will engage the edges of the socket, securing the latch within the socket. The keeper is then inserted into the latch, where it is secured therein as described below. The adhesive backing of the keeper is exposed, and the moving member to be secured by the latch is brought into its closed position, in contact with the adhesive. When the adhesive is dry, the keeper will be secured in the proper position to engage the latch. 
     The latching and unlatching cycle begins with the hook beam in its upward vertical position, against one side of the housing opposite the shuttle. To actuate the latch, the moving member is moved into its closed position, thereby bringing the keeper and latch together, and inserting the keeper&#39;s hook into the latch. The keeper pushes the shuttle toward the bottom of the housing, causing the shuttle&#39;s skirt to push against the hook beam&#39;s bottom arm, rotating the hook beam&#39;s top hook into engagement with the keeper&#39;s hook. As the hook beam&#39;s top hook rotates, the detent boss near the hooked end of the beam is snapped onto the left side of the resilient finger of the housing thereby ensuring the proper position of the hook beam&#39;s top hook for engagement with the keeper&#39;s hook. At this point, the user will release pressure on the moving member, allowing the spring to push the shuttle upward, thereby pushing the keeper slightly upward. As the keeper pulls on the top hook of the hook beam, the hook beam is pulled into a vertical position. Proper vertical alignment of the hook beam is insured by the detent boss near the hooked end of the beam, which is constrained from moving back to its original position by the resilient finger of the housing. Continued upward motion of the shuttle is prevented by the keeper hook, which is held by the hooked end of the hook beam and blocks the shuttle from returning to its original position. The latch is now securely latched. 
     To unlatch the latch, the moving member is again pushed inward, thereby causing the keeper to push the shuttle inward. The overhang of the top portion of the shuttle pushes down on the hook beam&#39;s central projection, causing the hook beam to move down. As the hook beam moves down, the perpendicular projection or arm at the bottom of the hook beam contacts the ramp of the housing which creates a reaction force which rotates the top hook and stem of the hook beam away from the hook of the keeper which allows the keeper&#39;s hook to exit the latch. As the top hook is rotated away from the hook of the keeper, the detent boss at the top of the stem of the hook beam is snapped into the right side of the resilient finger of the housing. As pressure is released on the keeper, the shuttle moves fully forward. The shuttle&#39;s flange pushes on the side flange of the hook beam&#39;s top hook, thereby moving the hook beam back into its original position. Proper vertical alignment of the hook is ensured by the detent boss on the hook beam, which is constrained from moving back to its previous position by the resilient finger of the housing. 
     It is therefore an object of the present invention to provide a latch wherein latching and unlatching is accomplished by an inward push by the keeper on the latch. 
     It is another object of the invention to provide a latch where proper alignment of the hook beam of the latch is insured during the latching and unlatching of the latch. 
     These and other objects of the invention will become apparent through the following description and claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a latch assembly according to the present invention. 
     FIG. 2 is a top view of a latch assembly and keeper according to the present invention. 
     FIG. 3 is a bottom view of a latch assembly and keeper according to the present invention. 
     FIG. 4 is a right side view of a latch assembly and keeper according to the present invention. 
     FIG. 5 is a left side view of a latch assembly and keeper according to the present invention. 
     FIG. 6 is a front view of a latch assembly and keeper according to the present invention. 
     FIG. 7 is a back view of a latch assembly and keeper according to the present invention. 
     FIG. 8 is a perspective view a latch assembly according to the present invention. 
     FIG. 9 is a left side view of a latch assembly according to the present invention. 
     FIG. 10 is a right side view of a latch assembly according to the present invention. 
     FIG. 11 is a top view of a latch assembly according to the present invention. 
     FIG. 12 is a bottom view of a latch assembly according to the present invention. 
     FIG. 13 is a front view of a latch assembly according to the present invention. 
     FIG. 14 is a back view of a latch assembly according to the present invention. 
     FIG. 15 is a perspective view of the hook beam for a latch assembly according to the present invention. 
     FIG. 16 is a top view of the hook beam for a latch assembly according to the present invention. 
     FIG. 17 is a bottom view of the hook beam for a latch assembly according to the present invention. 
     FIG. 18 is a right side view of the hook beam for a latch assembly according to the present invention. 
     FIG. 19 is a left side view of the hook beam for a latch assembly according to the present invention. 
     FIG. 20 is a front view of the hook beam for a latch assembly according to the present invention. 
     FIG. 21 is a back view of the hook beam for a latch assembly according to the present invention. 
     FIG. 22 is a perspective view of the shuttle for a latch assembly according to the present invention. 
     FIG. 23 is a top view of the shuttle for a latch assembly according to the present invention. 
     FIG. 24 is a bottom view of the shuttle for a latch assembly according to the present invention. 
     FIG. 25 is a left side view of the shuttle for a latch assembly according to the present invention. 
     FIG. 26 is a right side view of the shuttle for a latch assembly according to the present invention. 
     FIG. 27 is a front view of the shuttle for a latch assembly according to the present invention. 
     FIG. 28 is a rear view of the shuttle for a latch assembly according to the present invention. 
     FIG. 29 is a top view of the keeper for a latch assembly according to the present invention. 
     FIG. 30 is a front elevational view of the keeper for a latch assembly according to the present invention. 
     FIG. 31 is a view showing the back of the hook of the keeper for a latch assembly according to the present invention. 
     FIG. 32 is a rear view of a latch assembly according to the present invention, with the housing broken away to reveal the positions of the parts at the beginning of the latching cycle. 
     FIG. 33 is a front view of a latch assembly according to the present invention, showing the position of the parts at the beginning of the latching cycle. 
     FIG. 34 is a rear view of a latch assembly according to the present invention, with the housing broken away to show the position of the parts at the beginning of the latching cycle. 
     FIG. 35 is a front view of a latch assembly according to the present invention, showing the position of the parts at the beginning of the latching cycle. 
     FIG. 36 is a rear view of a latch assembly according to the present invention, with the housing broken away to show the positions of the parts after completion of the first step of the latching cycle. 
     FIG. 37 is a front view of a latch assembly according to the present invention, showing the position of the parts after completion of the first step of the latching cycle. 
     FIG. 38 is a rear view of a latch assembly according to the present invention, with the housing broken away to show the positions of the parts after completion of the first step of the unlatching cycle. 
     FIG. 39 is a front view of a latch assembly according to the present invention, showing the position of the parts after completion of the first step of the unlatching cycle. 
     FIG. 40 is a front exploded perspective view of a latch assembly according to the present invention. 
    
    
     Like reference numbers denote like elements throughout the drawings. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention is a latch wherein latching and unlatching are controlled by an inward push by the keeper towards the bottom of the latch housing, generally known as a push-push latch. Please note that the following description refers to a top, etc. for simplicity of reference only, and not to imply that the orientation of the latch is critical to its function. Referring to FIGS. 1-7 and  40 , the latch  10  includes a housing  12 , a hook beam  14  within the housing  12 , a shuttle  16  opposite the hook beam  14 , and a spring  18  biasing the shuttle  16  toward the top opening of the housing  12 . The latch mates with a corresponding keeper  20 . 
     Referring to FIGS. 8-11, the housing  12  is illustrated. The housing  12  is of one-piece construction, having a front  22 , back  24 , a right side  26 , a left side  28 , a top  30 , and a bottom  32 . The top  30  defines an opening  34 , having a narrow portion  36  corresponding to the right side  26  of the housing  12 , and a wide portion  38  corresponding to the left side  28  of the housing  12 . The front  22  and back  24  of the housing  12  each define an opening  40 . Each opening  40  contains an inner snap leg  42  extending from the top edge of the opening  40  downward and inward. The bottom edges of openings  40  include a notch  42  that forms a corner  44 . 
     The front  22  of the housing  12  further defines an additional opening  46  on the same side as the hook beam  14 . A resilient finger  48  extends from the bottom edge of the opening  46  upward and slightly inward. The housing  12  also includes a ramp  52  (FIGS. 32,  34 ,  36 , and  38 ), which slants upward near the bottom rear corner of the housing  12 . The ramp  52  is located to the rear of the spring  18  and below the shuttle  16 . 
     The housing  12  is preferably secured in a socket by a pair of snap legs. The right side  26  and left side  28  each include an outer snap leg  60 , extending upward and outward from the bottom  32  of the housing  12 . Each outer snap leg  60  has a ridged top end  62 . 
     Referring to FIGS. 15-21, the hook beam  14  is illustrated. The hook beam  14  includes a top hook  80 , being dimensioned and configured to mate with the hook of the keeper  20  (described later). The bottom  82  of the top hook  80  is preferably a flat surface. A top flange  84  extends rearward from the top hook  80 . The hook beam includes a stem  88  which includes a small roughly prism-shaped detent boss  86  at the top of the stem near the top hook  80 . The hook beam  14  further includes a central projection  94  which is roughly trapezoidal in configuration. The top side  96  of the central projection  94  is flat and extends perpendicularly from one side of the stem  88 . 
     The bottom portion of the hook beam  14  includes a bottom arm  98 , which in the preferred embodiment has a roughly “L” shape with a flat end  99 . The bottom portion of hook beam  14  also includes a pair of opposing bosses  100 , being dimensioned and configured to fit within the front and back openings  40  of the housing  12 , below the inner snap legs  42 . Each boss  100  has a notch or cutout  102  in the form of a circular sector subtended by an angle of less than 180 degrees, being dimensioned and configured to engage the corner  44 . 
     Referring to FIGS. 22-28, the shuttle  16  is illustrated. The shuttle  16  defines a top portion  110  which is “T” shape in top plan view and configured to fit into the wide portion  38  corresponding to the left side  28  of the housing  12  opposite the hook beam  14 . The top portion  110  includes an overhang  112  which projects towards the hook beam  14 . A flange  116  extends outward from one side of the shuttle  16 , being dimensioned and configured to abut the top flange  84  of the hook beam  14 . The shuttle  16  is spring-biased forward. The shuttle  16  defines a spring channel  118 , dimensioned and configured to contain and guide a compression spring  18 . The shuttle  16  also includes a skirt  120  which extends downward and toward the beam  14  from the top portion  112 , and dimensioned and configured to engage the bottom projection or arm  98  of the hook beam  14 . 
     Referring to FIGS. 29-31, the keeper  20  is illustrated. The keeper  20  includes a top panel  130  and a hook  132 . The hook  132  is dimensioned and configured to pass through the wide portion  38  of the opening  34  of the housing  12  and to be engaged by the hook beam&#39;s top hook  80 . The hook  132  of the keeper  20  includes a bottom surface  134  for pushing inward on the top portion  110  of the shuttle  16 . The back of the top panel  130  preferably includes an adhesive  136  for securing the keeper  20  to one of the two components to be latched together using the latch  10 . 
     The latch  10  and keeper  20  will typically be mounted on opposing moving and nonmoving members, such as a door or drawer and the frame supporting the door or drawer (not shown, and well-known). Typically, the latch  10  will be installed on the nonmoving member, and the keeper  20  will be installed on the moving member, but this may be reversed without affecting the operation of the latch  10 . In addition, both members to which the latch  10  and keeper  20  are installed may be movable. The latch  10  will preferably be installed within a socket, with a preferred and suggested socket having the configuration of two intersecting rectangles, corresponding to the shape of the housing  12 , to ensure proper alignment. Merely inserting the latch  10  into the socket, with the bottom  32  of the housing  12  first, will cause the ridges  62  of the outer snap legs  60  to engage the edges of the socket, thereby securing the latch  10  within the socket. The keeper  20  is then inserted into the latch  10  for latching (as explained below), and the keeper&#39;s adhesive backing  136  is exposed. By bringing the moving member towards the nonmoving member, corresponding to the moving member&#39;s closed position, the keeper  20  is secured in the proper position on the opposing member to provide for latching and unlatching. 
     The operation of the latch  10  is illustrated sequentially in FIGS. 32-39. The back side of the housing has been broken away to reveal the internal parts of the latch  10 . The initial unlatched position of the latch&#39;s components is illustrated in FIGS. 32-33. The hook beam  14  is adjacent to the right side  26  of the housing  12  opposite the shuttle  16  with the top flange  84  abutting the shuttle&#39;s flange  116 , and detent boss  86  on the stem  88  of the hook beam snapped into the right side of the resilient finger  48  of the housing. FIGS. 34-35 illustrate the bottom surface  134  of keeper  20  pushing inward on the top portion  110  of the shuttle  16 . As the shuttle  16  is pushed downward, the shuttle&#39;s skirt  120  pushes against the hook beam&#39;s bottom arm  98 . The shuttle&#39;s top portion  110  is simultaneously moved below the top hook  80  of the hook beam  14 . Because the hook beam&#39;s opposing bosses  100  are constrained within the housing&#39;s openings  40 , the hook beam  14  rotates counterclockwise (in the view shown in FIG. 34) so that the detent boss  86  on the stem  88  of the hook beam  14  moves from the left to the right side (in the view shown in FIG. 35) of the resilient finger  48  of the housing  12 . Simultaneously, the hook beam&#39;s top hook  80  engages the keeper&#39;s hook  132 . Proper alignment of the top hook  80  of the hook beam  14  for engagement with the hook  132  of the keeper  20  is insured by the detent boss  86  which is constrained from moving back to its original position by the resilient finger  48  of the housing. At this point, the user will release the pressure on the moving member, allowing the spring  18  to push the shuttle  16  slightly upward. As the shuttle  16  pushes the keeper  20  slightly upward, the hook  132  of the keeper  20  pulls on the top hook  80  of the hook beam  14  which will in turn pull the hook beam  14  into a vertical position. Proper vertical alignment of the hook beam  14  is insured by the detent boss  86  on the stem  88  of the hook beam which is constrained from moving back to its original position by the resilient finger  48  of the housing. Continued upward motion of the shuttle  16  is prevented by the keeper&#39;s hook  132  which is held by the top hook  80  and blocks the shuttle  16  from returning to its original position. The latch  10  is now securely latched as illustrated in FIGS. 36-37. 
     The latch  10  is unlatched by pushing inward on the moving member, which again causes the bottom surface  134  of keeper  20  to push inward on the top portion  110  of shuttle  16 . The overhang  112  of the top portion  110  of shuttle  16  pushes down on the top side  96  of the central projection  94  of hook beam  14 . The downward push on the central projection  94  causes the bottom end of the hook beam  14  to move downward, the bottom end of the beam  14  now being located at the end of the opening  40  closest to the shuttle  16 . This downward movement brings the corners  44  into interference with the notches  102 . This interference with the notches  102  prevents translation of the bottom end of the hook beam  14  along the openings  40 . As the hook beam  14  is pushed down by the overhang  112  of the shuttle  16 , the bottom of the bottom arm  98  of the hook beam  14  contacts the ramp  52  of the housing  12  which creates a reaction force which rotates the top hook  80  and the stem  88  of the hook beam  14  away from the hook  132  of the keeper  20  as shown in FIG.  38 . Simultaneously, the detent boss  86  at the top of the stem  88  of the hook beam  14  is snapped into to the left side of the resilient finger  48  as shown in the view of FIG.  39 . As the hook  132  of the keeper  20  is released from the top hook  80  of the hook beam  14 , the shuttle  16  is pushed forward by spring  18 . The shuttle&#39;s flange  116  engages the hook beam&#39;s top flange  84 , thereby moving the hook beam  14  back into its original position. Proper vertical alignment of the hook beam  14  is ensured by the detent boss  86  on the hook beam  14  which is constrained from moving back to its previous position by the resilient finger  48  of the housing  12 . The unlatching process is now complete, and the latch  10  is ready to repeat the cycle beginning with the view shown in FIG.  32 . 
     The assembly of the latch  10  is illustrated in FIG.  40 . Spring  18  is inserted into the spring channel  118  of the shuttle  16 , and the shuttle  16  is positioned adjacent to the hook beam  14  so that the flange  116  of the shuttle  16  abuts the bottom of the hook&#39;s top flange  84  and the top surfaces of the top hook  80  and the top portion  110  of the shuttle  16  are level with one another. The preassembled hook beam  14 , shuttle  16 , and spring  18  are then inserted through the top opening  34  of the housing  12 . The spring  18  is now compressed between the shuttle  16  and the bottom  32  of the housing  12 . The hook beam&#39;s bosses  100  snap into the openings  40  of the housing  12 , and are engaged by the resilient inner snap legs  42 . The shuttle&#39;s flange  116  abuts the hook beam&#39;s top flange  84 , thereby securing the shuttle  16 , hook beam  14 , and spring  18  within the housing  12 . In the unlatched, at rest position, the hook beam  14  is adjacent to the right side  26  of the housing  12 , with the top hook  80  resting against the overhang  112  of the top portion  110  of the shuttle, and the top flange  84  abutting the shuttle&#39;s flange  116 . 
     It is to be understood that the invention is not limited to the preferred embodiments described herein, but encompasses all embodiments within the scope of the following claims.