Abstract:
A compartment door latch mechanism requiring low amounts of torque to close the mechanism. The mechanism includes a top latch rod and a bottom latch rod. The top latch rod and the bottom latch rod are coupled to a plate via associated latch rod pins. The plate is coupled to a shaft around which the plate is capable of rotating the latch mechanism includes a lever suitably configured to facilitate the rotating of the plate. The geometry of the lever suitably provides a decreasing output and increasing input effective lever arms. The latch rod pins are positioned so as to engage the rods in a closed position at substantially 12:00 and 6:00 positions, respectively. In addition, the latch rod pins are further positioned so as to engage the rods in an open position at substantially 9:00 and 3:00 positions, respectively.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS  
       [0001]     This application claims priority from Provisional Application U.S. Application 60/740,057, filed Nov. 28, 2005, incorporated herein by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     This invention is directed to a compartment door latch mechanism; more particularly, to a compartment door latch mechanism requiring lower torque to engage the associated door latch rods in a door latch close position and in a door latch open position.  
         [0003]     Mobile truck bodies are typically modular in design and include at least two side packs. These side packs each include one or more storage compartments, suitably configured to enclose tools, equipment, and the like. The most common side pack compartment doors include a latch mechanism, which is difficult to turn when approaching a completely closed or completely open position. These common latch mechanisms generally require a large amount of torque. In addition, the amount of torque necessarily increases significantly as the latch mechanisms comes closer to a completely closed or completely open position.  
         [0004]     Thus, there is a need for a latch mechanism requiring less torque to engage the associated door latch rods in a door latch close position and in a door latch open position.  
         [0005]     There is also a need for a latch mechanism in which the torque decreases as the latch mechanism approaches a completely close or completely open position.  
       SUMMARY OF THE INVENTION  
       [0006]     There is provided a compartment door latch mechanism. Further, there is provided a compartment door latch mechanism requiring less torque to engage the associated door latch rods in a door latch close position and in a door latch open position. Still further, there is provided a compartment door latch mechanism requiring less torque to raise and lower associated door latch rods.  
         [0007]     There is provided a compartment door latch mechanism including a support plate rotatably mounted on a shaft and at least two latch rod pins affixed to the support plate at substantially equal predetermined distances from the shaft. The at least two latch rod pins extend substantially orthogonally from the support plate. The compartment door latch mechanism further includes a first latch rod and a second latch rod coupled to the support plate via respective associated latch rod pins. The first and second latch rods have respective substantially opposed initial orientations. The compartment door latch mechanism also includes a handle configured to facilitate the rotating of the support plate. The first and second latch rods are configured to transplace in a plane substantially parallel to the support plate to be engaged in a door latch close position and in a door latch open position. The handle, the first latch rod, and the second latch rod are spatially disposed such that in the door latch close position a projection of the handle onto a plane associated with the support plate is characterized by a first predetermined angular position relative to a projection onto the plane associated with the support plate of at least one of the first latch rod and the second latch rod. Preferably, in the door latch open position the projection of the handle onto the plane associated with the support plate of the at least one of the first latch rod and the second latch rod. In addition, the first and second latch rods are configured to maintain their respective initial orientations during operation of the door latch mechanism.  
         [0008]     Still further, there is provided a compartment door latch mechanism, comprising a support member adapted for rotating under an influence of input force and a latch coupled to the support member. The latch is adapted for transplacing in a plane substantially parallel to the support member to be engaged in a door latch close position and in a door latch open position. The compartment door latch mechanism also comprises a lever including a first arm and at least one second arm. The first arm is configured for receiving input force and is characterized by a first effective length. The at least one second arm is adapted for delivering output force to the latch and is characterized a second effective length. The lever is configured for respective changing of the effective lengths of the first and the at least one second lever arms such that the input force necessary for transplacing the latch continuously decreases as the latch advances to at least the door latch close position. The compartment door latch mechanism, preferably, includes a handle member attached to the support member. The support member is rotatably mounted on a shaft, which serves as the lever fulcrum. A radial portion of the support member extending from the shaft to the handle member in conjunction with the handle member serves as the first lever arm, wherein a radial portion of the support member extending from the shaft to the point of coupling of the latch to the support member serves as the at least one second lever arm.  
         [0009]     There is further provided a vehicle comprising a support platform. A support member is coupled to the support platform and configured to engage a surface. A compartment is coupled to the support platform and including a door. A compartment door latch mechanism is coupled to the door. The compartment door latch mechanism comprises a support plate rotatably mounted on a shaft and coupled to the door. At least two latch rod pins are affixed to the support plate at substantially equal predetermined distances from the shaft, the at least two latch rod pins extending substantially orthogonally from the support plate. A first latch rod and a second latch rod are coupled to the support plate via respective associated latch rod pins, the first and second latch rods having respective substantially opposed initial orientations. A handle is configured to facilitate the rotating of the support plate. Wherein the first and second latch rods are configured to transplace in a plane substantially parallel to the support plate to be engaged in a door latch close position and in a door latch open position. Wherein the handle, the first latch rod, and the second latch rod are spatially disposed such that in the door latch close position a projection of the handle into a plant associated with the support plate is characterized by a first predetermined angular position relative to a projection onto the plane associated with the support plate of at least one of the first latch rod and the second latch rod.  
         [0010]     Still other aspects of the present invention will become readily apparent to those skilled in this art from the following description wherein there is shown and described a preferred embodiment of this invention, simply by way of illustration of one of the best modes suited for to carry out the invention. As it will be realized by those skilled in the art, the invention is capable of other different embodiments and its several details are capable of modifications in various obvious aspects all without from the invention. Accordingly, the drawing and descriptions will be regarded as illustrative in nature and not as restrictive. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     The accompanying drawings incorporated in and forming a part of the specification, illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention. In the drawings:  
         [0012]      FIG. 1  is an isometric view of a door latch mechanism opened at substantially 9:00 and 3:00 rod position;  
         [0013]      FIG. 2  is an isometric view of the door latch mechanism illustrated in  FIG. 1  partially closed at a 10:30 and 4:30 rod pin position;  
         [0014]      FIG. 3  is an isometric view of the door latch mechanism illustrated in  FIG. 1  closed at substantially a 12:00 and 6:00 rod position.  
         [0015]      FIG. 4  is a schematic illustration of a truck type vehicle having a storage compartment with a door including an exemplary embodiment of a door latch mechanism.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0016]     There is disclosed a compartment door latch mechanism. In particular, a compartment door latch mechanism requiring less torque to engage the associated door latch rods in a door latch close position and in a door latch open position. In a preferred embodiment the latch mechanism is coupled to at least one compartment door on a mobile truck body. Also, in a preferred embodiment, the initial orientation of the first latch rod is an upward orientation, and the initial orientation of the second latch rod is a downward orientation. Those skilled in the art will appreciate that the door latch mechanism is also capable of being applied to other doors requiring locking mechanisms, and the instant description of a compartment door on a truck body, as well as the description of a latch mechanism with upward and downward oriented latch rods, is for illustration and example purposes only. It should be understood that the door latch mechanism can also be orientated to engage a door locking slot in a horizontal configuration.  
         [0017]     Turning now to  FIG. 1 , there is shown an isometric view of a latch mechanism  100  for a truck body compartment door in accordance with the present invention. The latch mechanism  100  includes at least two latch rods, illustrated in  FIG. 1  as a top latch rod  102  and a bottom latch rod  104 . As illustrated in  FIG. 1 , the top latch rod  102  has an upward orientation, and the bottom latch rod  104  has a downward orientation. The mechanism  100  also includes a support plate  110 , from which perpendicularly extend a top rod latch pin  106  and a bottom rod latch pin  108 . The top rod latch pin  106  and the bottom rod latch pin  108  are fixedly attached to the support plate  110 . It will be appreciated by those skilled in the art that the top rod  102  and the bottom rod  104  are coupled to the support plate via respective associated latch rod pins  106  and  108 , and maintain their respective initial orientations during operation of the latch mechanism  100 .  
         [0018]     The skilled artisan will appreciate that as shown in  FIG. 1 , the rod latch pins  106  and  108  are at the 9:00 and 3:00 position, respectively, indicating that the latch mechanism  100  is in the open position. It will be also appreciated by those skilled in the art that to close the latch mechanism  100  of  FIG. 1 , a force is suitably applied to the handle  114 , which functions to rotate clockwise the support plate  110  around the shaft  112 . In turn, the rotation of the support plate  110  serves to turn the rod latch pins  106  and  108  so as to force the latch rods  102  and  104  to extend, respectively, in an upward and downward direction, thereby engaging the distal end of each of the latch rods  102  and  104  into a corresponding locking slot (not shown) of the compartment door. The skilled artisan will appreciate that in the geometry of the instant latch mechanism  100  the handle  114 , being attached to the support plate  110 , together with a respective radial portion of the support plate  110 , suitably serves as a first lever arm with the shaft  112  serving as a fulcrum. A radial portion of the support plate  110  between the shaft  112  and a respective rod latch pin  106  and  108  suitably serves as a second lever arm. As will be recognized by those skilled in the art, as the handle  114  is moved clockwise, the effective length of the first lever arm (input server arm) increases, whereas the effective length of the second lever arm (output lever arm) decreases. Thus, as the handle  114  is moved clockwise, i.e. as the compartment door latch mechanism approaches the door latch close position, the less force is required to turn the handle  114 .  
         [0019]      FIG. 2  illustrates an isometric view of a partially closed latch mechanism  100 . The latch mechanism includes the same relative components as the latch mechanism  100  of  FIG. 1 , however the position of the rod latch pins  106  and  108  are illustrated in the 10:30 and 4:30 positions, respectively. The latch mechanism  100  includes a support plate,  110  rotatable around a shaft  112 . The support plate  110  is turned by force applied to a lever arm formed by a handle  114  together with a respective radial portion of the support plate  110  to continue closing the latch  100 . The rotation of the plate  110 , to which the rod pins  106  and  108  are perpendicularly attached, forces the latch rods  102  and  104  to extend, respectively, in an upward and downward direction. A skilled artisan will appreciate that the effective length of the first lever arm in the particularly closed latch mechanism  100  as depicted in  FIG. 2 , has increased with respect to the effective length of the first lever arm in the open latch mechanism  100 , as illustrated in  FIG. 1 . At the same time, as the skilled artisan will appreciate, the effective length of the second lever arm in the partially closed latch mechanism  100  has significantly decreased with respect t the effective length of the second lever arm in the open latch mechanism  100 . As such, the input force necessary to move the latch rods  102  and  104  towards the engaged position, continuously decreases as the latch means advances to the door latch close position. It will be understood by those skilled in the art that the closer the latch mechanism  100  becomes to the closed position depicted in  FIG. 3 , the less force is required to turn the handle  114 , i.e., close, the latch  100 . It will be understood by those skilled in the art that the latch rods  102  and  104  are advantageously designed so as to engage side walls of a compartment, the top and bottom walls of a compartment, or any combination thereof.  
         [0020]     Referring now to  FIG. 3 , there is shown an isometric view of a latch mechanism  100  for a truck body compartment door, wherein the latch mechanism  100  is in the closed position. The latch mechanism  100  includes at least two latch rods, illustrated in  FIG. 3  as the top latch rod  102  and the bottom latch rod  104 . The mechanism  100  also includes a support plate  110 , from which perpendicularly extend a top rod latch pin  106  and a bottom rod latch pin  108 . The skilled artisan will appreciate that as shown in  FIG. 3 , the rod latch pins  106  and  108  are at the 12:00 and 6:00 positions, indicating that the latch mechanism  100  is in the closed position. It will be appreciated by those skilled in the art that to open the latch mechanism  100  of  FIG. 3 , a force is suitably applied to the handle  114  to move the handle  114  counterclockwise. The handle  114  together with a respective radial portion of the support plate  110  functions as a first lever arm to rotate the plate  110  around a shaft  112 . Another radial portion of the support plate  110  located between the shaft  112  and a respective rod latch pin  106  and  108  suitably serves as a second lever arm. The rod latch pins  106  and  108  are attached to the shaft  112 . Hence, the rotation of the plate  110  serves to turn the rod latch pins  106  and  108  so as to force the latch rods  102  and  104 , respectively, to retract from the close position thereby disengaging the rods  102  and  104  from the locking slots (not shown) of the compartment door.  
         [0021]     Referring to  FIG. 4 , a vehicle  10  is shown according to an exemplary embodiment. Vehicle  10  is (shown as a services truck) includes a support structure  15  (e.g. frame, bed, platform, chassis etc.) and one or more support member  20 . According to various exemplary embodiments, support members  20  may be wheels, trucks, or any other member that are in communication with both the ground and the support structure  15 . A storage compartment  25 , having a door  30 , is coupled to the support structure. The door  30  includes a door latch mechanism  100  configured to secure the door  30  in a closed position. The door latch mechanism  100  can be oriented to operate in a vertical or horizontal manner.  
         [0022]     For purposes of this disclosure, the term “coupled” means the joining of two components (electrical or mechanical) directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally formed as a single unitary body with one another or with the two components or the two components and any additional member being attached to one another. Such joining may be permanent in nature or alternatively may be removable or releasable in nature.  
         [0023]     The foregoing description of a compartment door latch mechanism has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiment was chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to use the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled.