Patent Publication Number: US-6042159-A

Title: Door handle assembly

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to handle assemblies and more particularly to handle assemblies for controlling the latch mechanisms on vehicle doors. 
     Vehicle doors typically include a latch mechanism for latching and unlatching the door to the vehicle body, a handle assembly positioned on the door and operative to control the latch mechanism, and a lock mechanism to selectively render the handle assembly effect or ineffective to operate the latch. It is imperative that side impact against the vehicle, resulting for example from a collision, not result in the inadvertent movement of the handle of the handle assembly to a latch release position with consequent movement of the latch to an unlatched position and consequent inadvertent opening of the door. This in general is not a problem when the door is locked since in this case the door handle is either precluded from movement by the lock mechanism or the door handle is allowed to freewheel to its unlatched position but this movement is ineffective to move the latch to its unlatched position. However, when the door is unlocked, as is most typically the case in an operating vehicle, side impact can easily result in inertial movement of the door handle to its unlatched position with consequent unlatching of the latch mechanism, consequent opening of the door, and consequent discharge of unbuckled vehicle passengers from the vehicle. 
     Various attempts have heretofore been made to address the side impact problem and specifically to avoid inadvertent opening of the vehicle door in a side impact situation. In the most commonly employed arrangement, a heavy duty spring is employed in association with the door handle This spring may be sized, for example, to preclude movement of the door handle to its open position in crash situations involving up to 30 Gs of impact force. Whereas this arrangement satisfies the existing Federal Motor Vehicle Safety Standards with respect to side impact, it also results in a door handle that is very difficult to open because of the heavy duty spring employed in association with the door handle. This arrangement has the further disadvantage that the magnitude of the side impact force that the door handle assembly can withstand without inadvertent opening of the door is limited by the strength of the spring associated with the door handle so that, for example, if the door handle spring is sized to resist a 30 G impact force, any side impact force in excess of 30 G will result in opening of the door. 
     SUMMARY OF THE INVENTION 
     This invention is directed to the provision of an improved door handle assembly for use with a vehicular door. 
     More specifically, this invention is directed to the provision of a vehicle door handle assembly that operates to preclude inadvertent opening of the door in the event of a side impact against the vehicle. 
     The invention door handle assembly is intended for use with a vehicle including a door and a latch assembly mounted on the door and controlled by the door handle assembly. The door handle assembly in known manner includes a door handle adapted to be grasped by an operator and mounted proximate an exterior surface of the door for movement between a latched position in which the latch assembly maintains the door in a latched condition and an unlatched position in which the latch assembly is moved to an unlatched condition. 
     According to the invention, the door handle assembly includes a side impact detector member operative in response to a side impact against the door with the handle in its closed position to move inertially from a neutral position, allowing movement of the handle to its open position, to a side impact position, blocking movement of the handle to its open position. This arrangement provides a simple and effective means of precluding inadvertent opening of the door in a crash situation. 
     According to a further feature of the invention, the assembly provides less resistance to movement of the side impact member to its side impact position then to movement of the door handle to its open position. This arrangement ensures that the side impact member will move to its blocking, side impact position prior to movement of the door handle toward its open position. 
     According to a further feature of the invention, the door handle assembly includes an actuator lever operated by the handle and mounted for pivotal movement in response to movement of the handle, and the side impact detector member comprises a lever pivotally mounted on the actuator lever. This arrangement provides a simple and effective means of providing the desired blocking action in a side impact situation. 
     In the disclosed embodiment of the invention, the actuator lever comprises a bellcrank lever; the bellcrank lever is pivotally mounted between its ends to the door; the side impact lever is pivotally mounted to the free end of one leg of the bellcrank lever; the door handle assembly further includes a link pivotally mounted to a free end of another leg of the bellcrank lever and operating the door latch of the door handle assembly; and the door handle is pivotally mounted at one end thereof on the door and engages at another end thereof with the bellcrank lever at a location between the bellcrank lever pivot axis and the free end of the one leg of the bellcrank lever. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a fragmentary perspective view of a motor vehicle including a door embodying the door handle assembly of the invention; 
     FIG. 2 is a top view of the handle assembly in a door closed position; 
     FIG. 3 is a top view of the handle assembly in a door open position; 
     FIG. 4 is a fragmentary end view looking in the direction of the arrow 4 in FIG. 3; 
     FIG. 5 is a top view of the door handle assembly in a side impact condition; 
     FIG. 6 is a fragmentary end view looking in the direction of the arrow 6 in FIG. 5; 
     FIG. 7 is an enlarged view taken within the circle 7 in FIG. 5; 
     FIG. 8 is a perspective, fragmentary somewhat schematic view of the invention door handle assembly incorporated in a vehicular door assembly; and 
     FIG. 9 is an exploded fragmentary perspective view of a portion of the handle assembly. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The invention door handle assembly 10 is seen in FIG. 1 in association with a fragmentarily shown motor vehicle 12 including a windshield 14, a front quarter panel 16, a hood 18, an A pillar 20, a sill 22, a B pillar 24, and a door 26 positioned in the door opening defined by the A pillar 20, front quarter panel 16, sill 22, and B pillar 24. 
     Door handle assembly 10, broadly considered, includes an escutcheon or housing 28, a handle 30, an actuator lever 32, a side impact lever 34, and a coil spring 36. Escutcheon 28 includes a main body portion 28a defining a cavity 38, a peripheral flange portion 28b suitably secured to door 26 to position the escutcheon in a suitable opening 26a in the door 26, and a stop portion 28c. Stop portion 28c defines a stop surface 28d extending generally parallel to the plane of the door and a further stop surface 28e extending inwardly from surface 28d and extending generally normal to the plane of the door. A plurality of successive teeth or serrations 28f are provided on stop surface 28d. 
     Handle 30 includes an elongated main body portion 30a sized to fit within cavity 38 and a leg portion 30b provided at one end of the main body portion. The other end of the main body portion includes a lug 30c receiving a pivot pin 41 mounted on a lug 28g on the escutcheon to pivotally mount the handle on the escutcheon. Leg 30b extends inwardly from main body portion 30a, passes through a suitable opening 28i in the escutcheon, and defines an opening 30d proximate the inner end 30e of the leg portion. 
     Actuator lever 32 has a bellcrank configuration including a first leg portion 32a and a second leg portion 32b. Actuator lever 32 is pivotally mounted at the juncture of leg portions 32a, 32b on a pivot pin 39 mounted on a lug 28h on the escutcheon with the leg portion 32b extending loosely and slidably through opening 30c in the leg portion 30b of the handle. Opening 30c will be seen to be oversized with respect to the thickness of leg 32b. A slot 32c, defining an opening 32b, is provided in the free end 32e of leg portion 32b. A coil spring 40 surrounds pivot pin 39 and is arranged to yieldably resist counterclockwise pivotal movement of the actuator lever and thereby resist opening movement of the handle. 
     Side impact lever 34 is bifurcated proximate one end 34a of the lever and a weight 34b is provided at the other end of the lever. A pivot pin 34c is provided at the bifurcated end of the lever and is pivotally received in the slot 32c in the free end 32e of the leg portion 32b of the actuator lever. A plurality of successive arcuately arranged teeth or serrations 34f are provided on weight 34b proximate an offset end 34g of the weight. Teeth 34f are sized for ratcheting, latching coaction with teeth 28f on stop surface 28d. 
     Coil spring 36 is positioned in surrounding relation to a free end 34d of pivot pin 34c, passes at its cranked inner end 36a through a slot 34e in pin free end 34d so as to rotate with pin 34c, and is received at its outer end 36b in an anchor hole 32f in the free end 32e of the actuator lever. Spring 36 is arranged to normally maintain side impact lever 34 in a neutral position forming a linear extension of the actuator lever and extending generally parallel to the plane of the door, but to readily allow pivotal movement of the side impact lever about the axis of pin 34c in a counterclockwise direction. This pivotal movement of the side impact lever is resisted by coil spring 36 which is sized to maintain the side impact lever in its neutral position forming a linear extension of the actuator lever during normal operation of the door handle assembly but which offers minimal resistance to counterclockwise movement of the side impact lever about the axis of pin 34c. Coil spring 36 may, for example, be formed of piano or music wire. 
     As best seen in FIG. 8, door handle assembly 10 is intended for use with a vehicular door assembly including door 26, a latch assembly 43 positioned on the shut face 26b of the door, a key cylinder lock 44 positioned in the outer skin 26c of the door proximate door handle assembly 10, and a push button lock 46 positioned on the top sill 26d of the door in overlying relation to latch assembly 43 and coupled for joint operation with key cylinder lock 44. 
     Latch assembly 43 is of known form and includes a latch member 48 coacting with a bolt 50 on the confronting face of the vehicular structure to pivotally move the latch member 48 between its illustrated solid line unlatched position and its dotted line latched position. Latch assembly 43 further includes a dog 52 coacting with a detent on latch member 48 to maintain the latch member in its latched condition against the bias of a spring (not shown) and operative when released to allow the latch member to return under the bias of the spring to the unlatched position and thereby move the door to an unlatched position. Dog 52 is controlled in known manner by a link or rod 54 secured to the free end of actuator lever leg portion 32a. 
     Specifically, pivotal movement of bellcrank 32, with key cylinder 44 and push button 46 in an unlocked condition, has the effect of releasing the latch 48 for movement to an unlatched position. However, latch assembly 43, in known manner, further includes a decoupling mechanism 56 (shown schematically) which serves to render the rod 54 ineffective to release the latch member 48 when the push button 46 and lock cylinder 44 are in a locked condition. 
     The normal operation of the door handle assembly is seen by a comparison of FIG. 2 (door handle assembly closed) and FIG. 3 (door handle assembly open). Specifically, as the door handle assembly is moved from the closed configuration of FIG. 2 to the open configuration of FIG. 3, the leg portion 30b of the handle slidably engages the leg portion 32b of the bellcrank actuator to pivot the bellcrank about its pivot axis and exert a pulling force on rod 54 to release latch assembly 43 and allow opening movement of the door. Side impact lever 34 does not interfere with this movement since it is maintained in a position forming a linear extension of bellcrank arm 32b by coil spring 36, and, as best seen in FIG. 4, passes above the stop portion 28c of the escutcheon plate. The side impact lever, therefore, does not interfere in any way with the normal movement of the door handle assembly from the closed position seen in FIG. 2 to the open position seen in FIG. 3. 
     However, side impact lever 34 functions to preclude movement of the door handle from the closed position of FIG. 2 to the open position of FIG. 3 in the event of a side impact, such as represented schematically by arrow 58 in FIGS. 1 and 8. Specifically, in the event of a side impact 58 against the door 26, side impact lever 34, acting inertially, pivots immediately about the axis of pin 34c to the blocking position seen in in FIG. 5 and 7. In this position, offset end portion 34g of weight 34b is in confronting relation to escutcheon stop surface 28e and escutcheon stop surface 28d. Escutcheon stop surface 28e coacts with offset end portion 34g of weight 34b to limit and define the pivotal movement of the side impact lever and stop the lever in a position in which it extends generally in a direction normal to the plane of the door, and escutcheon stop surface 28d coacts with offset end portion 34g of weight 34b to preclude any significant amount of pivotal movement of the handle 30 about the axis of pin 41. Any such incipient pivotal movement of the handle is terminated immediately by engagement of the offset end portion 34g of the weight with stop surface 28d. Weight teeth 34f and stop surface teeth 28f coact upon arrival of the weight at a position proximate the surface 28e to latch the side impact lever in a position proximate stop surface 28d and extending generally perpendicular to the plane of the door. 
     It will be understood that the spring constants and other parameters of the system are chosen such that spring 40 offers substantially more resistance to pivotal movement of the handle about the axis of pin 41 than spring 36 offers to the pivotal movement of the side impact lever about the axis of pin 34c so that the inertial forces generated upon the side impact operate to swing the side impact lever to its blocking position before the handle has a chance to pivot toward its unlatched position. It will be seen that weight 34b, in addition to providing offset end 34g for coaction with escutcheon stop surfaces 28d and 28e, also serves to move the center of gravity of side impact lever 34 further outwardly with respect to the pivot axis of the side impact lever so as to enhance the inertial pivotal movement of the side impact lever in response to a side impact. 
     The invention door handle assembly will be seen to provide an effective means of precluding inadvertent unlatching of a vehicle door latch mechanism in the event of side impact while yet not providing any significant resistance to a normal opening movement of the door handle. Specifically, since handle spring 40 need only provide enough resistance to pivotal movement of the handle to allow the side impact lever to move first to its blocking position rather than itself providing the resistance to opening movement of the door handle in a side impact situation, the resistance to opening movement provided by spring 40 may be maintained within normal, comfortable limits. Further, whereas the prior art use of the spring 40 to preclude movement of the door handle in the event of side impact limits the ability of the door handle to resist side impact to the G forces that may be resisted by the spring 40, in the invention door handle assembly there is no limit to the G forces that may be resisted since the invention arrangement results in the creation of a solid blocking link that precludes inadvertent opening of the door irrespective of the magnitude of the G forces generated by the side impact. 
     Whereas a preferred embodiment of the invention has been illustrated and described in detail. It will be apparent that various changes have been made in the disclosed embodiment without departing from the scope and spirit of the invention.