Camper shell inside door lock
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation-in-part of U.S. patent application Ser. No. 683,482, now abandoned, entitled &#34;Camper Shell Inside Door Lock&#34;, filed Dec. 19, 1984, by the inventor herein. 
    
    
     BACKGROUND OF THE INVENTION 
     The background of the invention will be discussed in two parts. 
     1. Field of the Invention 
     This invention relates generally to door locks for light camper shell doors, and particularly to door locks for campers that fit on pickup trucks and have a short bar or an elongate bar that engages a portion of the truck frame or another portion of the camper shell for securing the door. 
     2. Description of the Prior Art 
     In the camper field the need for an inside door lock has existed for some time. In large trailers and motor homes, the doors are provided with locks that lock from both outside and inside. However, in more recent years, there has been a wisespread increase in the use of camper shells for pickup trucks. Although the majority of such camper shells are intended for assembly to the pickup truck with the tail gate still attached to the truck, some camper shells provide larger door openings for entry by campers, with the larger door entries being accommodated by removal of the tail gate. Such camper shells are normally secured to the pickup truck, such as by bolts, usually accessible from the interior of the shell. One or more doors may be provided for access to the compartment within the shell formed by the pickup truck bed and the shell. 
     In the first instance, the doors generally pivot about the roof of the shell, that is, the door pivots about a horizontal hinge. In the larger camper shell units, the door or doors pivot about a vertically disposed hinge arrangement attached to the camper shell. On virtually all camper shells, the door is provided with a locking arrangement which permits locking only from the outside. Such locks are intended to deter the theft of the contents of the truck in the pickup bed when the vehicle is unattended. However, such camper shells have achieved popularity for camping purposes, in which event, it is desirable to provide some means for locking the door from the interior when the pickup bed is used for sleedping quarters. 
     The locking mechanisms on such camper shells differ in design, but follow one of three basic configurations. In one instance, the simplest method for a vertically or horizontally hinged door is to provide a short locking bar which is fixed relative to, and pivots with, the door handle, and engages a stationary part of the shell or tail gate in the closed position, thus latching the door. The locking mechanism can be locked only from the outside and simply prevents rotation of the handle from the exterior. 
     In a more complicated door latching arrangement, the handle on the door operates a lever arm on the interior, rotation of which axially displaces an elongate locking bar which passes through an eye fixed to and adjacent an end of the door, in proximity to a slot or catch opening on a stationary part of the shell or truck. Rotation of the door handle then moves the end of the locking bar into or out of the catch opening. In the more sophisticated latching arrangements, a pair of locking bars are manipulated simultaneously by the handle lever with a pair of aligned catch openings in a stationary part of the shell or truck being simultaneously engaged. The locking bars in such instances are exposed and accessible from the interior of the camper shell. 
     It is accordingly an object of the present invention to provide a new and improved locking apparatus for use on the interior of a camper shell. 
     It is another object of the present invention to provide a new and improved camper shell locking apparatus which engages the locking bars of presently existing latching arrangements for camper shells. 
     It is still another object of the present invention to provide a new and improved camper shell locking apparatus which engages the locking bars of presently existing latching arrangements for camper shells and which can be readily attached to existing camper shells. 
     SUMMARY OF THE INVENTION 
     The foregoing and other objects of the invention are accomplished by providing a locking apparatus which includes a metallic plate member having a generaly right-angularly disposed integrally formed pivot portion for pivotally attaching thereto a latch arm, the latch arm having a latch portion defining a recess or opening for captively receiving therein the locking bar, with a transversely bent portion of the latch arm being configured for grasping and pivoting of the latch arm. A coating protrusion and depression are formed on abutting surfaces of the pivot portion and latch arm for retaining the parts in an open position to prevent inadvertent locking of the apparatus due to movement of the vehicle. The plate member is secured to a portion of the camper shell in proximity to the locking bar, with the opening of the latch arm aligned for capture and retention of the locking bar. The opening has an angularly disposed outer edge to force the latch arm down on attempted intrusion by rotation of the door handle from the exterior. 
     Other objects, features and advantages of the invention will become apparent from a reading of the specification when taken in conjunction with the drawings, in which like reference numerals refer to like elements in the several views. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the locking apparatus according to the invention secured to a door of a camper shell for engaging an articulated elongate locking bar thereof; 
     FIG. 2 is an exploded perspective view of the locking apparatus according to the invention; 
     FIG. 3 is a plan view of the assembled locking apparatus of FIG. 2; 
     FIG. 4 is a front view of the locking apparatus of FIG. 3; 
     FIG. 5 is an end view of the locking apparatus of FIG. 3; 
     FIG. 6 is a front view of an alternate embodiment of the locking apparatus according to the invention assembled to a camper shell door for engagement with a short locking bar thereof; and 
     FIG. 7 is an exploded perspective view of the locking apparatus of FIG. 6. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, and particularly to FIG. 1, there is shown a door locking apparatus, generally designated 10, attached to the interior of a camper shell door 12. The door locking mechanism 10 includes a door handle (not shown) on the exterior of the door 12, rotation of which rotates a shaft 16 of square cross-section. Keyed to the shaft 16 for rotation therewith is a symmetrically configured actuating lever 18 which is pivotable through an angle of approximately ninety degrees to the position shown in dotted lines. 
     One or more elongate locking bars 20, 22, each have first ends thereof pivotally attached to the ends of the lever 18, such as with rivets, for reciprocation of the bars 20, 22 in response to movement or pivoting of the shaft 18 of the door handle. Such bars 20, 22 may have a flattened portion at the said first ends for facilitating coaction with the lever 18 which is usually formed as a stamped piece of bar stock metal. The opposite ends 20b, 22b, of the locking bars 20, 22 may be flat, or preferably of round cross-section, and are suitably restrained for slidable vertical movement only, as viewed in FIG. 1, by means of restraining members 24, 26 suitably attached to the interior of the door 12 adjacent the upper and lower edges, respectively, thereof. 
     Each restraining member 24, 26 is configured with an elongate opening for passage therethrough of the end 20b, 22b, of the locking bars 20, 22, respectively. The ends 20b, 22b are slidable within the restraining members 24, 26, with the openings thereof having a width sufficient to permit a certain amount of lateral movement, and a depth slightly greater than the dimension of the end 20b, 22b of the bars 20, 22. 
     Briefly, it is the function of the restraining members 24, 26 to permit a certain amount of sideways movement of the ends 20b, 22b, while permitting limited movement or play in a direction perpendicular to the plane of the drawing. Adjacent the ends 20b, 22b, are a pair of aligned catch openings 28, 30 configured for receiving therein the ends 20b, 22b, respectively, with the locking mechanism 10 in the closed or locked position. These openings 28, 30 are normally formed, for example in opposing jamb portions of the doorway formed in the camper shell. 
     In such camper shells, as previously discussed, the door 12 may be hinged vertically or horizontally, and it is to be understood that the illustration of FIG. 1 may be rotated ninety degrees clockwise to depict a door 12 hinged horizontally. Furthermore, with respect to the catch openings 28, 30, it is to be understood that either or both of the openings may be formed in a separately attached bracket member, or may be formed in the pickup truck bed or sidewalls. In any event, the catch openings 28, 30 are in fixed relation to the pickup truck bed. 
     In the locked or latched postion, as shown in solid lines in FIG. 1, the locking bars 20, 22 are in axial alignment, and generally parallel to the hinge thereof (not shown), or to the edge 12a of the door 12. As the handle is rotated ninety degrees, resulting in the lever 18 being in the dotted line position, the ends 20b, 22b of the locking bars retract, that is they move to the dotted line positions 20b&#39;, 22b&#39;, in which the extreme ends are near the restraining members 24, 26 and inside the vertical dimension of the door 12 to permit the door to be opened. 
     Referring now, also to FIGS. 2 through 5, the locking apparatus 10 includes a plate member 40 and a latch arm 50 pivotally attached thereto by suitable means such as a rivet 56. Each of these members is formed such as by stamping and bending from a single piece of sheet metal of sufficient thickness for the required rigidity. The plate member 40 has a plate-shaped base portion 40a and a right-angularly extending pivot portion 40b at one edge thereof. The base portion 40a is a broadly dimensioned mounting plate with a plurality of apertures 42a, 42b and 42c formed therein for passage therethrough of suitable fastener members, such as screws 43. 
     The pivot portion 40b is of shorter dimension than the edge 40c of plate 40 for reasons which will become obvious. The pivot portion 40b at the upper end thereof, that is the end removed from the base portion 40a, is rounded, with an arcuate recess 44 formed therein. A pivot aperture 45 is located centrally relative to the radius of curvature of the rounded edge of the pivot portion 40b. An aperture or depression 46 is formed in the surface of the pivot portion 40b adjacent the aperture 45, the depression 46 being angularly displaced from the recess 44. 
     A latch arm member, generally designated 50, is formed from shaped sheet metal which is angularly bent to form first and second mutually perpendicular generally planar portions. The first planar portion 50b has, extending outwardly thereform, end portion 50c which forms a thumb or finger grip for pivoting of the latch arm member 50. The portion 50b forms a generally slightly tapered surface, tapering more narrowly away from end portion 50c. The second planar portion of latch arm member 50 has an arcuately configured portion 50a at the end thereof closest to end portion 50c and a spaced finger 50d formed at the opposite end, with the intervening space defining a latch recess 52. As can be seen in FIGS. 2 and 4, the inner edge of finger 50d, which, in part, defines the latch recess 52, diverges inwardly and downwardly, as viewed in FIG. 4, the purpose of which will be hereafter described. 
     A pivot aperture 54 is formed in the side of arctuate portion 50a at the approximate center of the radius of the arctuate portion 50a. A suitable fastening member such as rivet 56 passes through the aperture 54 and through aperture 45 of plate member 40, with the opposite end thereof receiving a washer member 57, after which the end of rivet 56 is swaged to pivotally join members 40 and 50, with portion 40b of plate member 40 in relatively movable abutting relation with the radiused side of portion 50a of latch arm member 50. A protrusion 58 is formed in the surface of the radiused side of portion 50a, the protrusion 58 extending toward the adjacent surface of portion 40b of plate member 40. The protrusion 58 is displaced radially from the aperture 54, which defines the axis of pivoting, with the distance and angle of displacement being selected for coaction with both the depression 46 and recess 44 of plate member 40. 
     By referring to FIGS. 2, 4 and 5, the purpose of these coacting protrusion and recess means will be described. In FIG. 4, the latch arm member is shown in solid lines designated 50, and in dotted lines designated 50&#39;. A locking bar 20 is shown in dotted lines within the latch recess 52. In this position, which corresponds to the position shown in FIG. 1, the locking bar 20 is captively retained within the latch recess 52, with the depending end of finger 50d in proximate relation to the base portion 40a of the plate member 40. If an intruder were to attempt to open the door 12 from the outside, the bar 20 would move to the left, as viewed in FIG. 4, that is, toward the finger 50d. The bar 20 would then urge against the tapered edge of finger 50d, which acts to apply a downward force on the finger 50d. Thus the adjacent edge of finger 50d acts as a hook means to secure the bar 20 against forcible movement. 
     In the solid line position shown in FIG. 4, the protrusion 58 of the latch arm member 50 is coactingly detented within the depression 46 of the plate member 40. When the occupants desire to open the door 12, the latch arm member 50 is pivoted clockwise, as depicted in FIG. 4, by application of pressure to the thumb portion 50c, this clockwise pivoting continuing until the protrusion 58 coactingly detents within the arcuate recess 44 of plate member 40. In this position 50&#39; of latch arm member 50, the member 50 is pivoted about sixty degrees, with the finger portion 50d elevated from the door 12 a distance sufficient to permit manipulation of the locking bars 20, 22 to an open position. 
     Additionally, it is to be emphasized that the latch arm member 50 in the dotted line position is sufficiently fixed to withstand pivoting while the vehicle is in motion, or when the vehicle is abruptly jarred. The frictional engagement occasioned by use of the arcuate recess 44 for maintaining the latch arm 50 in an open position assures that a much greater force is required to relatively pivot the parts, than the coaction of the protrusion 58 with the depression 46. In the closed position of the locking apparatus 10, a slight amount of movement is desirable to permit the camming action of the tapered edge of finger 50d when subjected to force. 
     FIGS. 6 and 7 demonstrate an alternate embodiment of the apparatus, the locking apparatus thereof being generally designated 60. The apparatus 60 includes a plate member 62 and a latch arm portion 64 suitably pivotally connected by rivet 66. The latch arm member 64 is virtually identical to latch arm member 50, however, the plate member 62 is configured somewhat differently than plate member 40. The plate member 62 includes a generally planar base potion 62a and a pivot portion 62b extending at right angles thereto. However, the pivot portion 62b is positioned intermediate the edges 62c and 62d of the base portion 62a. Viewing plate member 62 in end view, it is generally T-shaped, whereas plate member 40, when similarly viewed, is generally L-shaped. Furthermore the base portion 62a is more rectangular than base portion 40a, thus simplifying the stamping operation. The plate member 62 is provided with suitable apertures 67 for connection to a surface 70 of the vehicle or camper shell, as shown in FIG. 6. 
     In FIG. 6, the door 72 includes a door latch mechanism which is of the simplest variety, that is, the door handle shaft 75 is keyed to a short locking bar 77, which may be pivoted through an angle of about ninety degrees to the dotted line position 77&#39;, for locking and unlocking, respectively. In the locked position, as shown in solid lines, the locking bar 77 simply abuttingly overrides an adjacent surface 70, which is fixed relative to the vehicle, and which may be a portion of the camper shell, or may simply be the tail gate of the vehicle. The apparatus 60 is secured to the surface 70, such as by screws, in a position for receiving a part of the end of locking bar 77 within the opening 68 (FIG. 7) of latch arm 64 of apparatus 60. 
     The opening 68 is configured identically to the opening 52 of latch arm 50, and functions in the same way, that is, an attempt to rotate the locking bar 77 will result in a force being applied on the latch arm 64 in a direction toward the base portion 62a of the plate member 62. The position of the arcuate recess 69 on the pivot portion 62b and the coacting protrusion 71 on the latch arm member 64 have been slightly altered to facilitate manufacture, but still serve to keep the parts pivoted through an angle of about sixty degrees, with the frictional coaction maintaining the parts opened while traveling. 
     It is to be understood that either of the locking apparatus 10 or 60 may be used with any of the types of locking mechanisms currently utilized for pickup camper shells. Such locking apparatus, in accordance with the invention, may be readily mass-produced with suitable metal forming equipment, and provide an economical approach to assuring the safety of the occupants within the camper shell. While there have been shown and described preferred embodiment, it is to be understood that various other adaptations and modifications may be made within the spirit and scope of the invention.