Abstract:
A toolbox latch is disclosed having a pivoting handle mounted to a housing and mechanically linked to a pusher arm for setting in motion a series of linkages to trap and release a cooperating striker pin. The pusher arm rotates a swiveling trip lever when a turn-key member is first rotated into an unlocked position and the handle pulled in a pivoting motion away from the housing. The swiveling trip lever in turn rotates a rotating link member out of its locking position with a rotating lock lever, allowing a biasing spring on the rotating lock lever to rotate out of its trap position. The cooperating striker pin is thus freed from the trap position as the rotating link member disengages with the rotating lock lever and the latch is open. When the cooperating striker pin is brought back into proximity with the rotating lock lever as the toolbox is being closed, the force of the striker pin rotates the rotating lock lever back to the trap position, and a biasing spring returns the rotating link member back into engagement with the lock lever to prevent the lock lever from releasing the striker pin.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention is directed generally to mechanical latching mechanisms, and more particularly to a toolbox rotary latch that opens to release a striker pin on a toolbox lid, and releasably traps the striker pin upon closing the toolbox, where the release of the striker pin is accomplished by actuating a pivoting handle mounted on the housing, and wherein the handle includes a turn-key member to lock and unlock the latch device. 
   2. Description of Related Art 
   Rotary latches are used in many applications such as doors, chests, cabinets, and the like where a lid or door needs to be held or locked in a closed position. Rotary latches are preferred in some applications because they can be designed to spring open upon latch release and may be slammed shut to a closed or locked position. 
   Rotary latches can be found in many existing applications. U.S. Pat. No. 6,502,871 to Malmanger issued Jan. 7, 2003 entitled “Rotary Latch System and Method” discloses a rotary latch for opening and closing a panel or door. U.S. Pat. No. 6,454,321 to Parikh issued Sep. 24, 2002 entitled “Rotary latch Operated By a T-Handle With Multiple Latch Actuator Connection Points” discloses a rotary latch with a T-handle that translates rotation to an actuating lever for triggering a trip pawl to release a latch jaw. U.S. Pat. No. 5,884,948 to Weinerman et al. issued Mar. 23, 1999 entitled “Rotary Latch and Lock” discloses another type of rotary latch. However, none of the latch mechanisms described in the references above are particularly suited for a toolbox. 
   The rotary latches of the prior art lack a simple but reliable activating latch or handle adapted for light weight applications such as toolboxes. 
   The rotary latches of the prior art lack a simple but reliable activating latch or handle adapted for light weight applications such as toolboxes. 
   SUMMARY OF THE INVENTION 
   The present invention is a rotary toolbox latch having a pivoting handle mounted on a housing with a first end disposed on a pivot pin and a second end freely pivotable thereabout. A return spring is preferably mounted on the pivot pin and cooperates with the handle to bias the handle into the housing cavity. The handle further includes a turn-key member that rotates within the handle&#39;s free end, and the turn-key member is mechanically linked to a pusher arm where rotation of the turn-key member results in a corresponding rotation of the pusher arm. As a result of the rotation of the turn-key member, the pusher arm has two positions—a “lock” position that does not engage a swiveling trip lever, and an “unlocked” position that engages the swiveling trip lever. When the turn-key member rotates the pusher arm into the unlocked position, an actuation/pivoting of the handle about the pivot pin rotates the free end of the handle away from the housing to linearly displace the mechanically linked pusher arm. The linear displacement of the pusher arm causes it to come into contact with and pivot a swiveling trip lever. The trip lever includes a gear tooth that, when rotated by the pusher arm, rotates a rotary link member mounted to the housing. The rotary link member is mounted on a cylindrical post and biased in a rotationally preferred direction against the rotation resulting from the gear tooth. The rotary link includes a drive tooth that engages the gear tooth of the trip lever to rotate the rotary link member against the biasing force. Adjacent the rotary link member is a rotating lock lever having a U-shaped latch catch that rotates from a trap position with the U-shaped latch catch opening against the surface of the housing to close the U-shaped opening, to an untrapped position where the U-shaped latch catch is rotated away from the housing to release the cooperating striker pin enclosed therein. The rotation of the rotary lock lever is achieved when the rotating link member is rotated by the swivel trip lever, thereby rotating a locking pawl on the rotating link member out of a notch on the rotating lock lever. With the locking pawl evacuated from the notch by the rotation of the rotating link lever, the rotating lock lever is free to rotate about its cylindrical post. Preferably, a biasing spring mounted on the cylindrical post springs open the U-shaped latch catch to the open position when the locking pawl is rotated out of the mating notch on the rotating lock lever. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an elevated perspective view of one embodiment of the rotary latch of the present invention; 
       FIG. 2  is a front view of one embodiment of the rotary latch of  FIG. 1 ; 
       FIG. 3  is a top view of one embodiment of the rotary latch of  FIG. 1 ; 
       FIG. 4  is an elevated rear perspective view of one embodiment of the rotary latch of  FIG. 1  with the turn-key member in the locked position; 
       FIG. 5  is a left side view, partially in shadow, of one embodiment of the rotary latch of  FIG. 1  with the handle retracted into the housing; 
       FIG. 6  is a left side view, partially in shadow, of one embodiment of the rotary latch of  FIG. 1  with the handle deployed in an extended position; 
       FIG. 7  is an elevated rear perspective view of the preferred embodiment of the rotary latch of  FIG. 1  with the turn-key member in the unlocked position; 
       FIG. 8  is a top view of one embodiment of the rotary latch of  FIG. 1 , partially in shadow, showing the rotation of the trip lever with deployment of the handle; 
       FIG. 9  is a cross-sectional view taken along section lines  9 — 9  of  FIG. 8  of one embodiment of the rotary latch of  FIG. 1 ; 
       FIG. 10  is a cross-sectional view taken along section lines  9 — 9  of  FIG. 8  of one embodiment of the rotary latch of  FIG. 1  showing the relative rotation of the rotary link member and the rotating lock lever with actuation of the trip lever; and 
       FIG. 11  is a partial cross-sectional view of the rotary latch of  FIG. 1  taken along section lines  9 — 9  of  FIG. 8  illustrating the release of the latch member with rotation of the link member and lock lever. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIGS. 1–11  illustrate a preferred embodiment of the rotary toolbox latch  10  of the present invention. A housing  20  is formed of a face plate  30  defining a first plane  40 , and a recessed cavity  50  formed into the face plate  30  to accommodate a pivoting handle  60 . A pair of parallel plates  15 , 16  rigidly mounted to the face plate further define the housing  20 . The parallel plates  15 ,  16  each comprise an upper surface  19  with a U-shaped mouth  18  sized to receive a striker pin  23  of a cooperating lid or cover (not shown). The face plate  30  has a generally planar front surface  28  that recedes to a rear wall  32  to form the cavity  50 . The cavity  50  is shaped to fit the ends of the handle  60  with a slight clearance  70  at each end, and expands around the central, narrowing portion of the handle  60  to permit grasping the handle with one&#39;s fingers. An arched middle portion  65  of the handle  60  preferably extends slightly outside the plane  40  defined by the face plate  30  as shown in  FIG. 3 . 
   The handle  60  is pivotally mounted at a base end  80  using a pivot pin  90  mounted in the housing  20 . The pivot pin  90  is preferably fixed in the housing  20  at respective ends  100  that are seated in voids in the housing  20 , and the handle  60  includes a traverse channel sized to receive the pivot pin  90  therein for rotational movement thereabout. A return spring  110  on the pivot pin  90  includes a first end  120  in contact with the handle  60  for biasing the handle into the cavity  50 . Grasping the handle  60  about the central portion  65 , a user can overcome the force of the return spring  110  and pivot the handle  60  away from the housing  20 . Releasing the handle  60  allows the return spring  110  to return the handle  60  back to the housing  20 . A plurality of holes  25  are spaced along the face plate  30  for attaching the latch  10  to its recipient apparatus, such as a toolbox. 
   The handle  60  includes a free end  120  opposite the base end  80  comprising an annular portion  130  surrounding a cylindrical turn-key member  140 . The turn-key member  140  includes a keyhole  150  and requires a key (not shown) to rotate the turn-key member  140  within the free end  120  of the handle  60 . Rotation of the key creates two positions for the turn-key member—an unlocked position and a locked position. 
     FIGS. 4-7  illustrate the actuation of the handle  60  and the cooperation of the turn-key member  140  to set in motion components that open the latching mechanism described more fully below. Behind the rear wall  150  of the housing  20 , the cylindrical turn-key member  140  extends rearwardly through an aperture  160  in the housing&#39;s cavity  50 . Secured to the end of the turn-key member  140  by a washer  170  and bolt  180  is a perpendicular pusher arm  190 . In  FIG. 4 , the pusher arm is shown in a “three o&#39;clock” position corresponding to a locked position. In  FIG. 7 , the pusher arm is shown in a “twelve o&#39;clock” position corresponding to an unlocked position. Rotation of the turn-key member  140  via the associated key rotates the pusher arm  190  between the locked and unlocked positions. In other words, by rotating the key within the keyhole  150  of the turn-key member  140 , the mechanical linkage of the pusher arm  190  and turn-key member  140  causes the pusher arm  190  to assume either the locked or unlocked positions as shown in  FIGS. 4 and 7 , respectively. 
   As the handle  60  is pivoted away from the housing  20  ( FIG. 6 ), the turn-key member  140  is withdrawn into the cavity  50  of the housing  20 , and pusher arm  190  is translated toward the housing as shown in  FIGS. 5 and 6 . The motion of the handle  60  is created by the grasping of the handle  60  about the middle portion  65  and pulling the handle against the biasing force of the return spring  110  until the pusher arm comes in contact with the back wall of the housing  150 , terminating the displacement of the handle  60 . Releasing the handle  60  causes the return spring  110  to withdraw the handle back to its original position and returns the pusher arm  190  to its original position spaced from the rear wall  150 . Two situations arise depending upon the position of the turn-key member  140 . If the turn-key member  140  is rotated such that the pusher arm  190  takes the locked position shown in  FIGS. 4 and 6 , an actuation of the handle  60  fails to engage a rotating or swiveling trip lever  200  because the path of the pusher arm  190  does not cross the trip lever  200  in the locked position. In this case, a user can pull the handle  60  but cannot open the latching mechanism, highlighting the importance of the key position in the operation of the device. 
   If the turn-key member  140  is rotated such that the pusher arm  190  is in the unlocked position as shown in  FIG. 7 , then actuation of the handle  60  and the resulting displacement of the pusher arm  190  causes the pusher arm  190  to come into contact with a swiveling trip lever  200 . Contact progresses to displacement as the handle  60  is pulled out of the cavity  50 , and the force of the pusher arm  190  on the trip lever  200  causes the trip lever  200  to rotate counterclockwise when viewed from above ( FIG. 8 ). The pusher arm  190  in the unlocked position during actuation of the handle  60  contacts a horizontal tab  210  of the trip lever  200 , forcing the rotation of the trip lever. The trip lever  200  is suspended from the housing  20  at plate  16  by a rivet or fastener  220  that permits rotation of the trip lever  200  thereabout. Thus, the displacement of the horizontal tab  210  by the force of the pusher arm  190  is translated into a rotation of the trip lever  200  about its fastener  220 . 
   The trip lever includes a tab that functions as a gear tooth  230  extending radially from the center of rotation (i.e., the fastener  220 ) and substantially perpendicular to the horizontal tab  210 . A portion of the plate  15  forms a lip  196  that contacts the gear tooth  230  of the trip lever  200  to limit the rotation of the trip lever  200 . The lip  196  prevents the trip lever  200  from rotating away from the housing  20  and further ensures that the horizontal tab  210  is always positioned in the path of the pusher arm  190  when the pusher arm  190  is in the unlocked position. Moreover, the gear tooth  230  is surrounded on the opposite side by a drive tooth  240  of a rotating link  250  described more fully below. A biasing spring  270  on the rotating link  250  forces the drive tooth  240  to capture the gear tooth  230  between the lip  196  and thus fix the position of the trip lever  200  in the absence of an external force. 
   Rotation of the trip lever  200  caused by the pusher arm  190  results in the displacement of the gear tooth  230  of the trip lever  200  against the drive tooth  240  ( FIGS. 9–11 ). The contact of the gear tooth  230  from the rotation of the trip lever  200  at the horizontal tab  210  pushes the drive tooth  240  linearly to the right as shown in  FIG. 10 . The force applied to the drive tooth  240  rotates the rotating link member  250  about its cylindrical post  260  and against the biasing force of the rotational spring  270 . When the trip lever  200  is rotated by the pusher arm  190 , the rotating link member  250  is thusly rotated about its cylindrical post  260  to the position shown in  FIG. 11 . 
   Prior to rotation of the rotating link member  250  ( FIG. 9 ), a radially projecting locking pawl  290  on the rotating link member is seated in a recess  300  of a rotating lock lever  280 . The occupation of the locking pawl  290  in the recess  300  prevents the rotating lock lever  280  from rotating in the counterclockwise direction shown in  FIG. 9 . The rotating lock lever  280  is mounted on a cylindrical post  310  and includes a biasing rotational spring  320  urging the rotation of the lock lever  280  so that the U-shaped catch  305  is projecting upward or “open.” With the locking pawl  290  positioned against the lock lever  280 , the position of the lock lever and the U-shaped catch  305  cooperate with the parallel plates  15 ,  16  at the U-shaped mouth  18  to capture a striker pin  23 . The striker pin  23  is preferably mounted to a lid of the toolbox such that closing the lid of the toolbox causes the striker pin  23  to move into the mouth  18  of the parallel plates  15 ,  16 . The downward movement of the striker pin  23  further rotates the lock lever  280  against the biasing force of the rotational spring  320  such that the lock lever  280  assumes the position shown in  FIG. 9 . In this position, the recess  300  is adjacent the locking pawl  290  of the rotating link member  250  and the presence of the locking pawl  290  prevents rotation of the lock lever thus capturing the striker pin between the parallel plates  15 ,  16  and the U-shaped catch  305  of the lock lever  280 . Until the rotating link member  250  and its locking pawl  290  are rotated out of the path of the lock lever  280 , the striker pin  23  cannot escape the trap formed by the cooperating parallel plates  15 ,  16  and lock lever  280 , retaining the lid of the toolbox in the closed position. This effectively locks the toolbox closed. 
   The toolbox is opened through the rotation of the rotating link member  250  through the trip lever  200 . As explained above, the actuation of the handle  60  when the pusher arm  190  is in the unlocked position results in a rotation of the trip lever  200  against the drive tooth  240  of the rotating link member  250 . The force of the gear tooth  230  on the drive tooth  240  transfers the rotation of the trip lever  200  to the rotating link member  250  as shown in  FIGS. 8 and 10 . Rotation of the rotating link member  250  causes the locking pawl  290  to evacuate the recess  300  of the lock lever  280 . Without the presence of the locking pawl  290  to prevent rotation of the lock lever  280 , the biasing spring  320  imparts a rotation of the lock lever  280  in the direction of the arrow  318  in  FIG. 10 . The rotation of the lock lever  280  releases the striker pin  23  from its trapped configuration between the parallel plates  15 , 16  and the lock lever  280 , permitting the egress of the striker pin  23  and the opening of the toolbox. The rotation of the lock lever  280  resulting from the force of the biasing spring  320  is halted by the presence of a stop tab  340  on plate  15 . 
   The closing of the toolbox lid brings the striker pin downward against the U-shaped catch  305  until it rotates back to the position shown in  FIG. 9 . As the lock lever  280  rotates and the striker pin  23  is brought into the opening of the mouth  18  of the housing  20 , the biasing spring  270  on the rotating link member  250  causes the rotating link member  250  to return to its position shown in  FIG. 9  with the locking pawl  290  seated in the recess  300  of the lock lever  280 . In this configuration, the latch  10  is once again secure until the turn-key member  140  is rotated to the unlocked position and the handle  60  actuated as described above. 
   The toolbox rotary latch just described is well suited for a toolbox with a pivoting lid that includes a striker pin traversely deployed on the lid portion of the toolbox for engagement with the latch device. The key that rotates the turn-key member is insertable into the handle from the front of the latch mechanism and permits the toolbox to be latched and locked when the turn-key member is rotated to the locked position described above. 
   The description of the preferred embodiments are illustrative only and should not be construed as limiting the scope of the invention. One of ordinary skill in the art can deviate from the just-described embodiments without departing from the spirit of the invention. For example, while a pivoting handle is preferred, another handle that pulls out from the housing at each end is also possible. The cooperation of the pusher arm with the turn-key member can take many forms and utilize additional mechanical linkages to alter the direction of the applied force and the direction of the translation and rotation of the various components, while still preserving the essence of the present invention. Thus, the scope of the present invention should not be limited by the descriptions above, but rather the scope of the invention is defined solely by the words of the claims presented below.