Abstract:
A movement prevention device for a vehicle door latch mechanism includes a body movable between blocking and non-blocking positions in response to sudden changes in inertia on the vehicle, such as during a side impact crash. The device interferes with movement of the handle to prevent unintended opening of the latch mechanism.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     The present regular U. S. Patent Application claims the benefits of U.S. Provisional Application Ser. No. 60/576,778 filed on Jun. 3, 2004. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates generally to automobile door handle mechanisms and, more particularly, the invention pertains to structures in such mechanism for inhibiting unintended movement of the mechanism and unintended opening of the door during a crash, such as a side impact crash.  
       BACKGROUND OF THE INVENTION  
       [0003]     Exterior door handle mechanisms for automobiles are provided in a variety of designs so that the shape and operation thereof compliment and add to the overall design and appearance of the automobile. Accordingly, door handles are provided in a variety of vertical and horizontal orientations. Some are provided recessed within the door panel. In operating a variety of door handle mechanisms, the exposed handle is lifted, pulled or otherwise moved to activate the latch mechanism. When the handle is released, a spring assists in returning the door handle to the closed position in which the latch mechanism engages to hold the door closed.  
         [0004]     In some known constructions, a latch lever is connected to a latch cable that is also connected to the latch mechanism designed to secure the door in a closed position. In one such known design, the lever pivots about a substantially horizontal axis. The latch lever has a center of gravity spaced significantly below the lever pivotal axis. The lever is rotated about the pivotal axis and biased by a spring such that, when the door handle is released, the latch lever is returned to a lowered position which places the cable in position for the latch mechanism to be secured, holding the door closed and latched.  
         [0005]     In spite of the biasing influence of a spring or counterweight structures in the door mechanism, a side impact crash can cause movement of the latch lever from the closed position toward the opened position. A significant side impact crash can cause the latch lever to move completely to the unlatch position, even without either the exterior door handle or the interior door handle having been actuated intentionally. This condition can potentially cause the door to unlatch, possibly allowing the door to swing open. An open door condition during a crash or roll-over exposes occupants of the vehicle, thereby increasing the possibility of injury to the occupants, including possible ejection.  
         [0006]     As a result, manufacturers are concerned with providing latch mechanisms that secure the door in closed positions even when side impact or roll-over crashes occur. However, any such securing structure must not render the door unduly difficult to open during normal use.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention provides a latch locking structure that is actuated by the crash event itself, not interfering with normal latch operation except in the event of a crash. Locking structure is moved by the force from the crash to engage the latch mechanism in such a way as to prevent unintended opening or release of the latch mechanism.  
         [0008]     In one aspect thereof, the present invention provides a latch mechanism with a handle having a pivot about which the handle is rotated. The handle has a latch position and an unlatch position when rotated about the pivot. A movement prevention device associated with the handle is movable between a non-blocking position and a blocking position in response to sudden change in inertia on the mechanism. The non-blocking position of the movement prevention device permits unrestricted movement of the handle between the latch and unlatch positions. The blocking position of the movement prevention device interferes with movement of the handle from the latch position to the unlatch position. A biasing means urges the movement prevention device to the non-blocking position.  
         [0009]     In another aspect thereof, the present invention provides a latch mechanism with a handle movable between closed and opened positions. A gear segment is connected to the handle and is moved upon movement of the handle. A gear damper has a rotor with a shaft and a gear disposed on the shaft. The gear is drivingly engaged with the gear segment. A movement prevention device is moveable between blocking and non-blocking positions. The movement prevention device includes structure interfering with movement of one of the gear segment and the gear when the movement prevention device is in the blocking position.  
         [0010]     In a still further aspect thereof, the present invention provides a movement prevention device for a door latch mechanism. The device includes a body moveable between blocking and, non-blocking positions and has structure positioned to interfere with operation of the latch mechanism only when the body is in the blocking position. A biasing means urges the body to the non-blocking position. The biasing means and the body are configured to yield to sudden significant changes in inertia, allowing the body to move from the non-blocking position to the blocking position.  
         [0011]     An advantage of the present invention is providing a movement prevention device for automobile door latches that does not interfere with normal operation of the latch mechanism for ingress and egress of occupants.  
         [0012]     Another advantage of the present invention is providing a movement prevention device for automobile door latches that is actuated by the force of a side impact or rollover crash to secure the latch in a closed position and prevent accidental disengagement of the latch mechanism.  
         [0013]     Yet another advantage of the present invention is providing a movement prevention device that can be incorporated into the latch mechanisms of other things, devices and structures such as bins, console doors, trays and the like in automobiles, other transport devices or structures other than vehicles.  
         [0014]     Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]      FIG. 1  is a side elevational view of a door handle mechanism having a movement prevention device in accordance with the present invention, the device shown in a state of normal operation;  
         [0016]      FIG. 2  is an elevational view similar to that of  FIG. 1  but illustrating the movement prevention device in a locking condition such as during a side impact or roll-over crash;  
         [0017]      FIG. 3  is an exploded view of the movement prevention device shown in  FIGS. 1 and 2 ;  
         [0018]      FIG. 4  is a perspective view of the door handle and movement prevention device, shown from an angle different from that of  FIGS. 1 and 2 ;  
         [0019]      FIG. 5  is an exploded view of another embodiment of a movement prevention device in accordance with the present invention;  
         [0020]      FIG. 6  is an elevational view of the embodiment of  FIG. 5 , shown installed in a vehicle door mechanism, with the movement prevention device illustrated in a condition of normal operation;  
         [0021]      FIG. 7  is an elevational view similar to that of  FIG. 6 , but illustrating the position of the movement prevention device during a crash; and  
         [0022]      FIG. 8  is an elevational view of yet another form of movement prevention device in accordance with the present invention, the device shown in a door latch mechanism and in a condition of locking engagement for preventing unintended unlatch of the door. 
     
    
       [0023]     Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use herein of “including”, “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof, as well as additional items and equivalents thereof.  
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0024]     Referring now more specifically to the drawings and to  FIGS. 1-4  in particular, numeral  10  designates a vehicle latch assembly in which a movement prevention device  12  is operatively associated with a damper  14 . Damper  14  is provided to control or dampen the movement of the door handle during normal use of vehicle latch assembly  10 , as a door having latch assembly  10  is opened and closed for ingress and egress of occupants and things. Device  12  is provided cooperatively associated with damper  14  to inhibit unintended opening of latch assembly  10  in the event of a side impact crash, rollover or other occurrence that provides excessive side force on the vehicle and latch assembly  10 .  
         [0025]     Latch assembly  10  includes a lift-type handle  16  including an arm  18  having a gear sector  20  thereon. Handle  16  is pivotable about a horizontal axis  22 . Pivotal movement of handle  16  about axis  22  upwardly and downwardly causes movement of gear sector  20  through an arc between the fully open and fully closed positions of handle  16 . Elevation of handle  16  actuates a latch mechanism (not shown) connected thereto to release a door having assembly  10  installed therein from a latched condition.  
         [0026]     Damper  14  is a gear damper having a housing  24  and a rotor  26  disposed therein. Gear dampers suitable for the present invention are known in many applications and can be provided for controlling and damping movement in one or both directions of rotation of rotor  26  relative to housing  24 . A shaft  28  from rotor  26  extends outwardly from housing  24  and has a gear  30  mounted thereon. Gear damper  14  is mounted in a support  32  within the door substantially parallel to axis  22 . Gear  30  on rotor shaft  28  is drivingly engaged with gear sector  20  of arm  18 . Thus, as handle  16  is raised or lowered and gear sector  20  moves through the arc defined thereby, gear sector  20  and gear  30  are in driving connection one with the other. Movement of handle  16  thereby turns rotor  26  relative to housing  24 , and the damping effect provided by damper  14  is conveyed through gear  30  to gear sector  20  and thus to the rotation of handle  16  about axis  22 . Damper  14  thereby controls movement of handle, and can be used to urge handle  16  to the lowered position in which the latch mechanism is secured. Under normal driving and use conditions, damper  14  holds handle  16  in the lowered position,  
         [0027]     Device  12  is operatively associated with damper  14 . A sliding plate  34  defines an elongated central slot  36  by which plate  34  is disposed on and about shaft  28  from rotor  26 . Gear  30  is disposed on shaft  28 , with plate  34  retained between gear  30  and damper housing  24 . A pair of elongated guide slots  38 ,  40  are provided on opposite sides of central slot  36 . Guide pins  42 ,  44  are received in slots  38 ,  40 , respectively. A spring  46  is provided beneath plate  34 , mounted on a spring post  48 . Spring  46  includes legs  50 ,  52  disposed against shaft  28  and an end of plate  34 . Spring  46  biases plate  34  to a disengaged position allowing operation of latch assembly  10  in normal manner. The normal operating position of latch mechanism  10  is illustrated in  FIG. 1 , wherein plate  34  can be seen biased to the left as illustrated in  FIG. 1 .  
         [0028]     A side impact or roll-over condition is illustrated in  FIG. 2 , with the force being designated by arrow  54 . The change in inertia from the force of the event has overcome the biasing force of spring  46 , causing slide plate  34  to move to the right relative to the other structures of latch assembly  10 , as illustrated in  FIG. 2 . Relative movement of slide plate  34  is directed by guide pins  42 ,  44  in slots  38 ,  40  and by central slot  36  around shaft  28 .  
         [0029]     Ends of plate  34  opposite the side engaged by spring  46  project outwardly on the top and bottom, having an open end in between the projections. As illustrated in  FIG. 4 , a bottom projection  56  extends beneath arm  18  when plate  34  is moved relative to the remainder of latch assembly  10 . Arm  18  can be provided with a stopper extension portion  58  which overlies bottom projection  56  when plate  34  is moved to the position shown in  FIGS. 2 and 4 . In this position of plate  34 , arm  18  is not able to move in that stopper portion  58  is blocked by bottom projection  56 . Thus, with rail-like projection  56  in the position illustrated in  FIGS. 2 and 4 , handle  16  cannot move and a door latch mechanism operated by handle  16  will not become disengaged unintentionally.  
         [0030]     Device  12  in accordance with the present invention can be modified for operation with a variety of different door structures and door handle arrangements.  FIGS. 5, 6  and  7  illustrate another embodiment of the present invention. Device  100  is operatively associated with a damper  102 . Again, device  100  is mounted on a rotor shaft  104  of damper  102 , between a housing  106  and a damper gear  108  of damper  102 . A spring  110  biases device  100  towards the disengaged position so that a handle mechanism on which it is mounted operates without interruption. Device  100  includes a central body  112  rotatable about shaft  104 , and outwardly extending arms  114  and  116 . Arm  116  defines an enlarged outer end  118  operating as a counter-weight to rotation of mechanism  100 .  
         [0031]      FIGS. 6 and 7  illustrate the normal ( FIG. 6 ) and impact ( FIG. 7 ) conditions for device  100  in a vehicle latch mechanism  120 . Latch mechanism  120  includes a handle  122 , the operation of which moves a gear rack  124 . During normal conditions, device  100  has no influence on the operation of latch mechanism  120 . Handle  122  is moved as necessary, and damper  102  provides the desired damping effect to the movement of handle  122 . The cooperative interaction of damper gear  108  and gear rack  124  conveys the damping influence of damper  102  to the movement of handle  122 . Upon a side impact or roll-over condition, as illustrated in  FIG. 7 , device  110  is rotated such that arm  114  engages rack  124 , inhibiting movement of rack  124 . Thus, without rack  124  being able to move handle  122  does not move, and the latch mechanism is secured in a closed condition.  
         [0032]      FIG. 8  illustrates yet another embodiment for a movement prevention device  140  of the present invention as part of a door latch mechanism  150 . Latch mechanism  150  includes a handle  152  operated for engaging and disengaging a latch (not shown). A damper  154  is provided in similar fashion to dampers  14  and  102  described previously. A damper gear  156  on a damper shaft  158  operatively engages structure (not shown) associated with handle  152  so that movement of handle  152  is contained and controlled as desired:  
         [0033]     Movement prevention device  140  includes a plate  160  having edge portions  162 ,  164  operating in slots  166 ,  168  defined in a housing structure  170 . Plate  160  defines a central opening  172  having a toothed section  174  therein. In a side impact or roll-over condition as illustrated in  FIG. 8 , plate  160  slides along slots  166 ,  168  defined in structure  170  such that toothed section  174  engages gear  156 . Accordingly, gear  156  is prevented from rotating, and because of the direct linkage of gear  156  to handle  152 , handle  152  cannot move when gear  156  is prevented from rotating.  
         [0034]     Each of the mechanisms described herein include structure which moves as a result of the change in inertia that occurs during a side impact collision, roll-over, or other such event. A portion of the moved structure engages or at least inhibits movement of structure associated with the handle of the vehicle door. Since the structure is required to move in order for the latch mechanism to disengage, by inhibiting movement of the relevant structure, the door handle cannot move and the latch does not become disengaged unintentionally.  
         [0035]     Variations and modifications of the foregoing are within the scope of the present invention. It is understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention. The claims are to be construed to include alternative embodiments to the extent permitted by the prior art.  
         [0036]     Various features of the invention are set forth in the following claims.