Abstract:
A sliding-action slam latch includes an integrally molded actuator having a rigid portion and an flexible portion, the flexible portion serving to bias the actuator closed. Pins extending from the rigid portion of the actuator contact guide surfaces on the latch body to limit travel of the actuator.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is a continuation of U.S. patent application Ser. No. 09/619,510, filed Jul. 19, 2000, now abandon which is a non-provisional application of U.S. Provisional Application No. 60/144,801, filed Jul. 21, 1999. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to latching devices, and more particularly to systems for latching hinged doors or panels and the like. 
   2. Background of the Invention 
   Various types of latching devices for fastening doors, panels and the like are known. 
   Door-mounted “slam” latches employ a camming surface on the end of a sliding-bolt element that cooperates with a striker on the door frame to cause a bolt action to secure the door when it is closed against the frame. Such latches are activated to secure the door when the door is merely pushed shut or slammed. However, to open the door, operation of the latch mechanism is required to release the latch. In some slam latches, as the door is being closed, the bolt is urged against a spring force by the action of a camming surface cooperating with the striker to slide into the latch housing. Once the camming surface has passed the door frame inner surface, the spring force then urges the bolt element to engage behind the door frame, or to engage a keeper mounted on the door frame. In order to open the door, the bolt is manually operated, usually through a grip, to withdraw the bolt from engagement with the keeper. 
   Examples of prior art slam latches are disclosed in U.S. Pat. Nos. 3,841,674, 3,850,464, 5,482,333 and 5,628,634. 
   The spring force for such latches can be provided through separate spring elements, such as a torsion bar spring (FIGS. 8–9, U.S. Pat. No. 3,841,674), a torsion coil spring (FIGS. 11–13, U.S. Pat. No. 3,841,674), or a compression coil spring (FIG. 13, U.S. Pat. No. 3,841,674). Alternatively, the spring element can be integrally molded with a latch body made from an appropriate plastic or polymeric material (FIGS. 1–7, U.S. Pat. No. 3,841,674; U.S. Pat. No. 5,842,333; FIG. 6A–6E, U.S. Pat. No. 5,628,534). 
   Slam latches with integrally molded spring elements have a number of advantages over slam latches that use separate metal springs. First, slam latches with integrally molded spring elements tend to be less expensive because fewer parts are required to be made and assembled for each latch. Further, during manufacture metal springs may become embrittled and thus subject to breakage. 
   On the other hand, prior art latches with integrally molded spring elements may not have the same life expectancy as those that use separate metal springs. Elements formed from polymeric materials that are subjected to cyclic stresses, such as integrally molded spring elements in slam latches, sometimes fail at stress levels far below their yield stress, due to fatigue failure. 
   Prior slam latches have employed generally planar integrally molded spring elements. Examples include those shown in FIGS. 1–7 of U.S. Pat. No.  3 , 850 , 464 , and FIGS. 6B–6E of U.S. Pat. No. 5,628,534. A variation is disclosed in U.S. Pat. No. 5,482,333, in which the spring member  5  includes two pairs of integrally hinged generally planar elements, molded from a suitable resin, such as polypropylene, in a relaxed configuration. In each of these designs, when the latch is operated stresses are generated primarily proximate the portion of the latch where the spring extends from the latch body. 
   There is a need for a simple, inexpensive slam latch having an integrally molded spring element that resists cyclic stresses and fatigue failure. 
   SUMMARY OF THE INVENTION 
   The present invention provides a latch of the sliding-action slam type for installation in an opening in a door or panel for releasably retaining the panel relative to a frame. The latch is particularly useful for securing carpeted panels, such as are found in automotive interiors. 
   The latch is adapted for installation in a generally rectangular opening or aperture formed in the panel near the edge of the door panel. 
   The latch includes a generally flat, rectangular plate which is positioned above the door panel when the latch is mounted in the opening. In a presently preferred embodiment, the plate extends beyond the edge of the panel and over the top of the frame, thereby serving to prevent inward movement of the panel beneath the frame. 
   The latch also includes a generally box-like latch body that extends under the plate and through the opening in the panel when the latch is mounted in the panel. The latch body forms a central well, and the well extends through a generally rectangular central opening that is formed in the plate. 
   The latch also comprises an actuator extending from the latch body for releasably engaging the frame. The actuator is accessible through the central well. The actuator includes a flexible portion and a rigid portion. The flexible portion comprises an integrally formed spring means for biasing the actuator forward. When the latch is operated, the actuator travels from a closed position to an open position. Pushing the actuator backward against the bias of the spring means operates the latch. The panel can then be swung or lifted open. When the actuator is released, the spring means restores the actuator to the closed position. Preferably, the actuator includes a middle section adapted for engagement by the operator. It is also preferred that the rigid portion of the actuator include a pawl for engaging the underside of the frame in the closed position. It is likewise preferred that the pawl include at least one angled surface adapted for engaging the edge of the frame so as to force the actuator backward against the spring means when the door or panel is slammed shut. 
   Preferably, the latch also includes camming means for controlling the travel of the actuator when the actuator is operated. The camming means preferably includes a first and a second opposed side wall of the latch body with respective first and second apertures formed therein. The camming means preferably also includes a first and second pin extending outwardly from the actuator adapted for travel within the respective first and second aperture when the latch is operated. Preferably, the latch is formed from a polymeric material resistant to cyclic loading, such as a synthetic acetal resin. This extends the duty life of the integral spring and thus the latch. 
   Lock tabs are formed on the outside of the sides of the latch body and are adapted to be compressed during installation of the latch. When the latch is installed by pushing the latch body into the opening in the panel, the lock tabs are first compressed by contact with the edge of the opening. Just before the bottom of the plate contacts the upper surface of the panel, the tabs spring outwardly, locking the latch in the panel. The desired positioning of the lock tabs depends on the effective thickness of the panel. For example, when the panel is carpeted, the effective thickness depends on the type and depth of the carpet pile. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is perspective view of a slide latch of the present invention, the slide latch being shown mounted in a panel and in a latch position securing the panel to a frame, the panel and frame being shown in section, the perspective being taken from above. 
       FIG. 2  is a perspective view of the slide latch of  FIG. 1 , the perspective being taken from below, the latch being shown in the closed position. 
       FIG. 3  is a side elevational view of the slide latch of  FIG. 1 , the latch being shown in the open position. 
       FIG. 4  is a sectional view of the slide latch of  FIG. 1 , the section being taken along the line  4 — 4  of  FIG. 2 . 
       FIG. 5  is a perspective view of the slide latch of  FIG. 1  as seen from above and to the front of the right side of the latch, the panel and frame being omitted to reveal the latch. 
       FIG. 6  is a side elevational sectional view of the slide latch of  FIG. 1 , the section being taken along the line  6 — 6  of  FIG. 5 . 
       FIG. 7  is a side elevational view of the slide latch of  FIG. 1 , showing the latch in the open position and the panel being opened. 
       FIG. 8  is a perspective view of the slide latch of  FIG. 1  showing the slide latch being mounted in the panel opening. 
       FIG. 9  is a side elevational sectional view of the slide latch of  FIG. 1 , the slide latch being shown in an open position with the spring means compressed and the front portion of the slide latch being disengaged from the frame so that the panel can be opened, the slide latch being sectioned to emphasize the operation of the actuator. 
   

   DETAILED DESCRIPTION 
   Referring now to the drawings in detail, wherein like reference numerals indicate like elements throughout the several views, there is shown in  FIG. 1  a perspective view of a slide latch  10  of the present invention, the slide latch  10  being shown mounted in a panel or door  160 , and in a closed or latched position securing the panel  160  to a frame  150 , the panel  160  and frame  150  being shown in a fragmentary section thereof. The latch  10  is preferably formed as a single component by a molding process from a polymeric material having substantial resistance to fatigue from cyclic loading. A particularly preferred polymeric material is acetal resin, available as Delrin® acetal resin from E.I. du Pont de Nemours, Wilmington, Del. 
   The latch  10  includes a latch body  20  and a generally rectangular plate  30  from which the latch body  20  downwardly extends. A central, generally rectangular well  22  extends through the plate  30  and into the latch body  20 . The latch  10  also includes an actuator  50  accessible and operable through the well  22 . 
   As shown in the side perspective view of  FIG. 2 , the latch body  20  includes a pair of opposed, generally planar and parallel side walls  24 ,  26 , and a rear wall  28 . As best seen in the sectional perspective view of  FIG. 6 , the actuator  50  is attached to the underside of the plate  30  and the side walls  26  (only one of which is visible in  FIG. 6 ) of latch body  20  proximate the rear wall  28  of the latch body  20 . However the actuator  50  is otherwise not attached to the side walls  24 ,  26  or the plate  30 , so that the actuator  50  is free to move as described below. 
   The actuator  50  is in the form of a continuous folded sheet and includes a plurality of sections variously provided with side walls for functional purposes as described below. 
   The actuator  50  includes a front section or pawl  60  extending from the front of the latch body  20 . As shown in  FIG. 2 , the pawl  60  contacts the underside of the frame  150  when the latch  10  is in the closed position to prevent outward rotation or travel of the panel  160  in which the latch  10  is mounted away from the frame  150 . Preferably, the plate  30  of the latch  10  extends beyond the edge  152  of the frame  150  ( FIG. 1 ) and over the frame  150  when the panel  160  is secured, so that the panel  160  extends between the underside of the plate  30  and the pawl  60 . When the actuator  50  is operated to move the actuator  50  from the closed position ( FIG. 2 ) to an open position ( FIG. 3 ), the pawl  60  is retracted rearward and downward so that it no longer extends under and adjacent the frame  150 , thus permitting the panel  160  to be opened, as shown in the side perspective view of  FIG. 7 . 
   As best seen in  FIG. 6 , the actuator  50  includes the pawl  60 , as well as a middle section  70  extending from the rear of the pawl  60 , and a rear section  110 , extending from the rear of the middle section  70 . 
   As best seen in  FIGS. 4–6 , the pawl  60  includes a pair of opposed, spaced, generally trapezoidal side walls  64 ,  66 , a generally rectangular, horizontal top wall  62  extending between the side walls  64 ,  66  at their respective upper ends, and a generally rectangular rear wall  68  extending between the side walls  64 ,  66  proximate their respective rear portions and extending from the rear of the top wall  62 . This construction is believed to provide a strong, rigid, lightweight structure for the pawl  60 . The front surfaces of the side walls  64 ,  66  are sloped so that when the panel is closed or slammed shut, the side walls  64 ,  66  of the pawl  60 ,contact the edge of the frame  150 , and the actuator  50  is pushed backward, thereby permitting the panel or door  160  to close. 
   The middle section  70  of the actuator  50  (best seen in  FIGS. 1 ,  4  and  6 ), extends continuously from the front section or pawl  60 . The middle section includes an upwardly extending first or forward pleat  80  having an upwardly and rearwardly sloping front wall  82  extending continuously from the rear wall  68  of the pawl  60 , a top or upper section  84  positioned approximately flush with the upper surface of the plate  30 , and a downwardly and rearwardly sloping rear wall  86  which terminates in a section that is approximately horizontal. The forward pleat  80  also includes a pair of opposed, spaced generally parallel side walls  88 ,  90  extending from and continuously formed with the respective edges of the front wall  82 , top section  84 , and rear wall  86 , thus providing rigidity to the forward pleat  80 . The pawl  60  and forward pleat  80  of the middle section  70  thus constitute two rigid portions of the actuator  50 . 
   Extending from either side wall  88 ,  90  of the forward pleat  80  are a pair of generally cylindrical guide pins  92 ,  94  which are positioned to extend into a pair of corresponding generally teardrop-shaped apertures  34 ,  36  formed in the side walls  24 ,  26  of the latch body  20 . The guide pins  92 ,  94  and respective apertures  34 ,  36  comprise camming means controlling the travel of the actuator  50  as described below. 
   The middle section  70  of the actuator  50  further comprises a rear pleat  100  having a front wall  102  which extends continuously rearwardly and upwardly from the rear wall  86  of the forward pleat  80 , a top or upper section  104  positioned approximately flush with the upper surface of the plate  30 , and a downwardly and slightly rearwardly sloping rear wall  106 . 
   The rear wall  86  of the forward pleat  80  and the front wall  102  of the rear pleat  100  together form a concavity  96  shaped to receive the finger of an operator. 
   The actuator  50  also includes a rear section  110  comprising a generally flat and rearwardly extending bottom wall  112  extending continuously from the bottom of the rear wall  106  of the rear pleat  100 , and an upwardly extending rear wall  114  extending from the back of the bottom wall  112  up to the underside of the plate  30  proximate the rear edge of the well  22 . 
   The rear pleat  100  and rear section  110  together comprise a flexible spring means for biasing the actuator  50  and pawl  60  forward. 
   As best seen in  FIGS. 2 and 6 , in the relaxed or normal configuration the pawl  60  is positioned so that the top wall  62  of the pawl  60  and the underside of the forward end of the plate  30  are generally parallel and spaced from one another by slightly more than the thickness of the frame  150 , thereby securing the panel  160  in a closed and locked position. To operate the latch  10  to open the panel  160  the operator places a finger in the concavity  96  and pushes downwardly and rearwardly against the front wall  102  of the rear pleat  100 . The travel of the rigid forward portion of the actuator  50 , namely the front pleat  80  and the pawl  50  is limited and defined by the camming action of the pins  92 ,  94  pressing against the respective edges of the apertures  34 ,  36  formed in the side walls  24 ,  26  of the latch body  20 . Simultaneously, the flexible rear portion of the actuator  50 , namely the rear pleat  100  and the rear section  110  are compressed, as best seen in  FIG. 9 . When the rigid forward portion of the actuator  50  has reached the ultimate limit of its rearward travel, such as depicted in  FIG. 3 , the pawl  60  extends no further forward than the edge  164  of the panel  160 , thereby permitting the operator to pull the panel open, such as depicted in  FIG. 7 . When the operator removes her finger from the concavity  96 , the spring means forces the rigid forward section of the actuator  50  forward. To close and lock the panel  160 , the operator can again manually retract the actuator  50  and push the panel  160  closed, or, in the alternative, can simply slam the panel  160  shut. When the pawl encounters the edge  162  of the door frame  150  as the panel is being shut, the contact by the outer edges of the side walls  64 ,  66  of the pawl  60  with the edge  152  of the frame  150  forces the rigid portion of the actuator  50  backward against the spring means. When the pawl  60  passes below the underside of the frame  150 , the spring means forces the rigid portion of the actuator  50  forward to position the pawl  60  once again below the frame  150 . 
   As best seen in the perspective views of  FIGS. 2 and 5 , the latch body  20  includes a plurality of lock tabs  40  formed in the side walls  24 ,  26 . A generally rectangular aperture  162  ( FIG. 2 ) is formed in the panel  160  proximate the edge thereof for mounting the latch  10  of the present invention. The latch  10  is installed by placing the pawl  60  under the forward edge of the mounting aperture  162  and pressing down. As the latch  10  is pressed down, the lock tabs  40  are initially pressed inwardly by the edge of the mounting aperture  162 , and finally snap outwardly to lock the latch  10  in the mounting aperture  162 . 
   The latch of the present invention may be adapted to be engaged by the operator in a different manner. For example, instead of a well formed in the latch body, the latch can include a post or button extending up above the upper surface of the flange to be grasped by the operator (not shown). 
   Various other modifications can be made in the details of the various embodiments of the apparatus of the present invention, all within the scope and spirit of the invention and defined by the appended claims.