Abstract:
A door handle assembly which is compact in size for space-efficient packaging in a door of an automotive vehicle. The assembly includes a safety system for preventing inadvertent movement of the handle to an unlatched position during a side impact collision. A counterweight is mounted in the handle assembly which, during relative motions of parts induced by acceleration from a side impact, resists unlatching the handle. The counterweight is rotatably mounted on an axis different from an axis of the handle latch control mechanism, and is not fixedly attached to the handle mechanism.

Description:
BACKGROUND OF THE INVENTION 
   This invention relates generally to door latches for vehicles, and in particular to a safety system in a door handle assembly which is compact in size for space-efficient packaging in the door. 
   Doors on cars and trucks include a handle assembly for latching and unlatching the door to the vehicle body so that the door can be swung open and also held in a shut position. A safety system is conventionally incorporated so that a side impact collision does not inadvertently cause the handle to move into an unlatched position, thereby allowing the door to open and exposing occupants to greater risk of being expelled from the vehicle. Typically, the safety system uses a counterweight mounted in the handle assembly which, in response to acceleration induced by a side impact, opposes or prevents movement of the handle to the unlatched position. 
   Recent vehicles feature doors of decreased thickness that require thinner and more compact handle assemblies. Unfortunately, conventional handle assemblies frequently have counterweights which are thick, bulky, located relatively far from the operating part of the handle assembly, or otherwise difficult to integrate into the door with a smooth contour and low profile. 
   SUMMARY OF THE INVENTION 
   In general, a door handle assembly according to the present invention is for a vehicle door that resists opening of a latch mechanism of the door under inertial forces. The door handle assembly comprises a handle movable from a door latched position to a door unlatched position. A bell crank is operatively connected to the handle so that movement of the handle rotates the bell crank about a bell crank axis. The bell crank has a first lever arm adapted for attachment to the latch mechanism of the door, and a cam. A counterweight is mounted for pivoting about a counterweight axis spaced from the bell crank axis. The counterweight is positioned for engagement with the cam such that when the handle is pulled from the door latched position to the door unlatched position, the bell crank rotates and the cam pushes the counterweight in a first direction about the counterweight axis. But upon acceleration of the handle assembly tending to cause the handle to move by its own inertia from the door latched to the door unlatched position thereby urging the bell crank to rotate, the inertia of the counterweight urges it to pivot in a second direction about the counterweight axis opposite the first direction and bear against the cam for inhibiting rotation of the bell crank and movement of the handle to the door unlatched position. 
   In another aspect, a door handle assembly of the invention is for a vehicle door that resists opening of a latch mechanism of the door under inertial forces. The door handle assembly comprises a handle movable from a door latched position to a door unlatched position. A latch control mechanism is operatively connected to the handle so that movement of the handle moves the latch control mechanism. A counterweight is mounted for pivoting about a counterweight axis and free of fixed connection to the latch control mechanism. The counterweight is positioned for contact with the latch control mechanism such that when the handle is pulled from the door latched position to the door unlatched position, the latch control mechanism moves and pushes the counterweight in a first direction about the counterweight axis. But upon acceleration of the handle assembly tending to cause the handle to move by its own inertia from the door latched to the door unlatched position thereby urging the latch control mechanism to move, the inertia of the counterweight urges it to pivot in a second direction about the counterweight axis opposite the first direction and bear against the latch control mechanism for inhibiting rotation of the latch control mechanism and movement of the handle to the door unlatched position. The counterweight and latch control mechanism in the door latched position are contained in a volume less than or equal to about 150 cm 3 . 
   Other objects and features of the present invention will be in part apparent and in part pointed out hereinafter. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a fragmentary perspective, partially exploded, of a lateral side of a vehicle with a door handle assembly of the present invention; 
       FIG. 1A  is a perspective of the door handle assembly of  FIG. 1 ; 
       FIG. 2  is an elevation of the door handle assembly of  FIG. 1  as viewed from interior of the door; 
       FIG. 3  is a horizontal section along line  3 — 3  of  FIG. 2  with the handle at a latched position; 
       FIG. 4  is an elevation seen from the vantage indicated by line  4 — 4  of  FIG. 2 ; 
       FIG. 5  is an enlarged, fragmentary horizontal section taken along line  5 — 5  of  FIG. 2 ; 
       FIG. 6  is a horizontal section taken along line  6 — 6  of  FIG. 2 , but with the handle pivoted outwardly to an unlatch position; 
       FIG. 7  is a perspective of a bell crank of the door handle assembly; 
       FIG. 8  is a perspective of a counterweight of the invention; 
       FIG. 9  is a bottom plan of the counterweight; and 
       FIG. 10  is a fragmentary perspective of a lateral side of a vehicle with a door handle assembly of a second embodiment. 
   

   Corresponding reference characters indicate corresponding parts throughout the views of the drawings. 
   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring now to the drawings and in particular to  FIGS. 1 and 1A , a door handle assembly according to the present invention is indicated generally at  10 . The assembly  10  is installed in a door  12  of a vehicle, such as a car or truck, for controlling a door latch mechanism  14  in unlatching the door from the vehicle body to open the door. The assembly  10  also inhibits inadvertent opening of the door  12  when the vehicle is involved in a collision, particularly an impact on a side of the vehicle which results in accelerations and/or forces in a lateral direction. 
   The assembly  10  includes a handle and a latch control mechanism, indicated generally at  20  and  30 , respectively. The handle  20  has a horizontal grip portion  32  for gripping the handle, a tail  34  ( FIG. 3 ) at a first end  36  of the handle, and a connection to the latch control mechanism  30  at a second, opposite end  38 . The handle  20  is pivotally movable between a latched position ( FIG. 3 ) and an unlatched position ( FIG. 6 ). In one embodiment as shown in  FIG. 1 , the assembly  10  is received in openings  40  in the door panel  12  and installed in the vehicle door with the tail  34  of the handle located at a relatively forward position and the latch control mechanism  30  at a relative rearward position. That arrangement places the latch control mechanism  30  at closer proximity to the door latch mechanism  14  for operative connection therebetween. Other arrangements do not depart from the scope of the invention. 
   The assembly  10  further includes a base  42  for securing the handle  20  to the door and establishing its pivotal motion. The base  42  includes a flat surface  44  ( FIGS. 1A and 2 ) which engages the door panel  12  and a semi-circular shaped hood  46 . The surface  44  has a fastener hole  48  which receives a fastener (not shown) to secure the base  42  and handle  20  to the door panel. The hood  46  projects from the flat surface  44  into the interior of the door panel. The hood  46  is configured for receiving and enclosing the tail  34  of the handle. The base  42  remains at a fixed position on the door panel  12 , and the handle  20  pivots about the base  42 . A center of rotation  50  of the handle  20  is shown in  FIG. 6 , the center defining a handle axis which is substantially vertical. An outer end  52  of the hood  46  rests against an inner side of the door panel  12  at a location spaced from the flat surface  44  and stabilizes the assembly  10  against rotation relative the door. 
   At the opposite, second end  38  of the handle  20 , a bracket  54  covers the latch control mechanism  30  and is shaped to provide a smooth external surface contour between the door panel and handle when the handle is at the latched position. The bracket  54  is fixedly secured to the door panel  12  by one or more fasteners (not shown). As shown in  FIG. 5 , the second end  38  of the handle is shaped to rest against the bracket  54  when the handle is at the latched position, with a flat surface  56  of the handle engaging a flat surface  58  of the bracket. 
   The handle  20  is operatively connected at its second end  38  to the latch control mechanism  30  such that, in ordinary operation, movement of the handle to the unlatched position causes the door latch mechanism  14  to unlatch from connection to the door frame so that the door  12  may be opened. A finger  60  ( FIGS. 5 and 6 ) projects from the second end of the handle  20  in a direction generally perpendicular to the door panel. The finger  60  is fixedly connected to the handle  20  and extends through an opening (not shown) in the flat surface  58  of the bracket. As shown in  FIG. 1A , the finger  60  has an elongate body with a central slot  62  and a solid, curved end  64  which closes the free end of the slot. When the handle  20  pivots from the latched position to the unlatched position, the finger  60  moves in the direction of arrow A ( FIG. 6 ). 
   The latch control mechanism  30  comprises a bell crank  66  which transfers force from the handle  20  into motion of a linking cable  68  ( FIGS. 3 and 5 ) which connects the latch control mechanism to the door latch  14 . The bell crank  66  is mounted for rotation about a hinge  70  defining a bell crank axis L ( FIG. 4 ). In one embodiment, the bell crank axis is substantially vertical. Referring to  FIG. 7 , the bell crank  66  has a cylindric hub or post  72  with a bore  74  for receiving a hinge pin to mount the bell crank between two supports  76 ,  78  of the assembly. A first lever arm  80  extends outward from the post  72 , substantially horizontally, and has a clevis end for attachment to the linking cable  68 . A second lever arm  82  extends from the post  72 , generally in the same horizontal plane as the first lever arm  80  but in the opposite direction. In one embodiment, the first lever arm  80  is generally straight while the second lever arm  82  curves more than 90 degrees, forming in combination a hook shape to the arms as shown in  FIGS. 3 and 5 . The second lever arm  82  is received in the slot  62  of the finger  60  and curves toward the free end  64  of the finger. Other configurations for transferring force from the handle to the linking cable do not depart from the scope of this invention. Further, the bell crank axis may have other orientations and arm(s) may have other shapes and orientations. 
   The bell crank  66  is positioned closely adjacent the inner side of the door panel  12  and the finger  60  of the handle. When the handle  20  pivots to the unlatched position and the finger  60  moves in a direction A ( FIG. 6 ), the end  64  of the finger pulls the second lever arm  82  and causes the bell crank  66  to rotate. The direction of rotation of the bell crank is counter-clockwise, as viewed in  FIGS. 5 and 6 . The first lever arm  80  simultaneously pulls the cable  68 , overcoming force urging the cable to the latched position. Movement of the linking cable  68  away from the latch mechanism  14  (i.e., when the first lever arm  80  rotates counter-clockwise) effects unlatching of the door. When the handle  20  is released, it returns (via spring bias) to the latched position with the finger  60  moving opposite the direction A, permitting the second lever arm  82  and bell crank  66  to rotate in a clockwise direction. Movement of the linking cable  68  toward the latch mechanism  14  (i.e., when the first lever arm  80  rotates clockwise) allows the latch mechanism to latch the door, or if the door remains open, allows movement of the latch mechanism to its latched position without actually latching to the vehicle frame. 
   The bell crank  66  has a cam  84  ( FIG. 7 ) extending from the post  72  which, in one embodiment, lies in a generally horizontal plane spaced from and parallel to the plane of the first and second lever arms  80 ,  82 . The cam  84  extends around a circumferential portion of the post  72  and is positioned below and in general alignment with the first lever arm  80 . An outer peripheral edge of the cam  84  includes a leading edge  88  ( FIG. 5 ), which is straight, an arcuate circumferential edge  90 , and a straight trailing edge  92  which lies generally tangent to the outer surface of the post. 
   A counterweight  100  is mounted in the assembly  10  as a safety system to prevent rotation of the bell crank  66  when the vehicle is involved in a side-impact collision. The counterweight  100  is free of fixed connection to the latch control mechanism  30 , being rotatably mounted separate from the bell crank  66  in an arrangement for engaging the bell crank. As shown in  FIGS. 8 and 9 , the counterweight  100  is a solid, generally L-shaped block with flat sides and straight edges. The counterweight is shaped and configured to fit closely adjacent to the inner side of the door panel  12  and bell crank  66  for providing space-efficient installation in the vehicle door, which has tightly limited volume constraints. In this regard, a portion of the counterweight  100  is in vertical registration with the finger  60  and the second lever arm  82 , shown in  FIG. 5 , when in the door latched position. 
   The counterweight  100  has a mounting formation  102  with a generally rectangular shape and a thickness less than adjacent portions of the counterweight. A bore  104  extends through the mounting formation  102  for receiving a hinge extending between fixed support  76  and a support  106  to mount the counterweight for pivotal motion. The hinge defines a counterweight axis of rotation M ( FIG. 4 ) which in one embodiment is co-planar with, parallel to, and spaced from the bell crank axis L. The counterweight axis M is located toward one side of the counterweight  100 , being spaced from a center of mass  108  of the counterweight, as shown in  FIG. 5 . The center of mass  108  is generally on the same side of the counterweight axis M as the location where the counterweight engages the cam  84 . A torsional spring  110  ( FIG. 4 ) is placed around the hinge to urge the counterweight  100  to rotate toward the bell crank  66 , i.e., counter-clockwise in the views of  FIGS. 5 and 6 . It is understood that the counterweight can have other shapes and configurations without departing from the scope of this invention. 
   A foot  112  ( FIG. 8 ) protrudes from the mounting formation  102  and functions as a stop, as discussed below. The foot  112  defines a flat shoulder  114  and a smoothly contoured tip. The outer surface of the counterweight  100  comprises a cam follower. Due to the force of the spring  110 , the counterweight continually engages the cam  84  (i.e., the outer edges  88 ,  90  of the cam) as the bell crank  66  rotates. 
   In normal operation, the counterweight  100  does not inhibit operation of the latch  14 . Referring to  FIG. 5  showing the latched position, the shoulder  114  of the foot  112  is in engagement with the leading edge  88  of the cam  84 . The force of the spring  110  urges the counterweight  100  to bear against the bell crank  66 , more specifically, the foot  112  contacts and bears against the leading edge  88 . The operator pulls the handle  20  toward the unlatched position, rotating the bell crank  66  and easily overcoming the opposing force. As the bell crank  66  rotates in the counter-clockwise direction, the cam  84  pushes against the counterweight  100  which causes the counterweight to rotate about the counterweight axis M in the clockwise direction. The counterweight  100  pivots out of the way so that the bell crank  66  may rotate and pull the linking cable  68 . As it rotates toward the unlatched position shown in  FIG. 6 , the counterweight  100  follows the motion of the cam  84 . The counterweight  100  has a relatively small range of motion so that it may more readily fit into tight spaces in the door without interference. For example, while the bell crank  66  rotates between latched and unlatched positions an angle more than 50 degrees, the counterweight  100  rotates clockwise an angle less than 20 degrees. Other angular ranges do not depart from the scope of this invention. 
   When the vehicle is involved in a side impact collision, the counterweight  100  resists operation of the latch  14 . When the vehicle accelerates in a lateral direction, components of the assembly  10  experience inertial forces that tend to move the components relative to the door panel  12  in a direction opposite the acceleration. Referring to  FIG. 5 , lateral acceleration of the vehicle in the direction of arrow B results in inertial forces on components in the direction of arrow C relative to the vehicle. The handle  20  tends to pivot to the unlatched position, thereby urging the bell crank  66  to rotate in the counter-clockwise direction. Because the counterweight&#39;s axis of rotation M is not located at the counterweight&#39;s center of mass  108 , nor aligned with it, a lateral inertial force in direction C tends to rotate the counterweight  100 . The rotational direction in  FIG. 5  to which it is urged is counter-clockwise about the counterweight axis. Consequently, the counterweight  100  (at the shoulder  114 ) bears against the bell crank  66  (at the leading edge  88 ) with a force substantially greater than that applied in normal operation. Accordingly, the bell crank  66  is locked and cannot rotate nor push the counterweight  100 . The foot  112  functions as a stop which resists or halts movement of the handle  20  to the door unlatched position. 
   Should the vehicle experience an opposite lateral acceleration, in the direction of arrow C on  FIG. 5  (i.e., an impact on the opposite side of the vehicle), the assembly  10  does not urge the door handle  20  to move to the unlatched position. Significantly, the counterweight  100  is not fixedly attached to the latch control mechanism  30 . Although the acceleration is in the direction opposite for which the assembly was designed, the counterweight  100  does not cause the handle  20  to move to the unlatched position. Inertia will cause the counterweight  100  to rotate in the clockwise direction, away from the bell crank  66 . The handle  20  will bear against the bracket  54  and remain at the latched position. 
   Significantly, the counterweight axis M is spaced from the bell crank axis L. That provides a mechanical advantage over systems with common axes, and the counterweight  100  may be relatively smaller while producing sufficient locking force to prevent movement of the handle  20  due to inertia. Consequently, the assembly  10  may be more compact. 
   Preferably, the counterweight  100  and latch control mechanism  30  (when in the latched position) are contained in a volume less than or equal to about 150 cm 3 , and more preferably the counterweight and latch control mechanism are contained in a volume less than or equal to about 74 cm 3 . 
   A second embodiment  120  of the door handle assembly is illustrated in  FIG. 10 . The second embodiment  120  operates in the same manner as described above, but is packaged within a unitary base  122 . An outer perimeter of the base  122  is received into a single opening  124  in the door panel  12 , instead of the several openings  40  in the door of the embodiment  FIG. 1 . The latch control mechanism  30  and the counterweight  100  are contained within the perimeter of the base  122 , forming an integrated unit which is readily installed in a door panel. 
   In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results obtained. 
   When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. 
   As various changes could be made in the above without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.