Abstract:
A latch is provided including a fork bolt configured to rotate between an unlatch position and a latched position. A detent is configured to cooperate with the forkbolt. A bumper includes an upper contact portion and an elongated lower portion. The bumper is configured to receive a striker when the fork bolt is in the latched position. A guide member includes a generally curved flexible portion. The flexible portion is configured to deflect about a first end to guide the striker towards the upper contact portion of the bumper.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/760,276 filed Feb. 4, 2013, the contents of which are incorporated herein by reference thereto. This application also claims the benefit of U.S. Provisional Patent Application Ser. No. 61/760,274 filed Feb. 4, 2013, the contents of which are also incorporated herein by reference thereto. 
     
    
     TECHNICAL FIELD 
       [0002]    Exemplary embodiments of the present invention relate generally to latches and, more particularly, to latches for vehicles. 
       BACKGROUND 
       [0003]    Latches are used to restrain the movement of one member or element with respect to another. For example, door latches restrain the movement of a door with respect to a surrounding door flame. The function of such latches is to hold the door secure within the frame until the latch is released and the door is free to open, Existing latches typically have mechanical connections linking the latch to actuation elements such as handles which can be actuated by a user to release the latch. Movement of the actuation elements is transferred through the mechanical connections that cause the latch to release. The mechanical connections can be one or more rods, cables, or other suitable elements or devices. 
         [0004]    Latch sound quality can enhance or detract from the overall perception of quality by an end user about the construction of the vehicle. For example, good sound quality may imply solid construction, smooth operation, and thoughtfulness of design. As a result, vehicle manufacturers are placing more emphasis on the ability of the door latch to absorb the noise emissions that may occur during a closing event. Sound quality metrics, such as minimal loudness and frequency content for example, are affected by many variables including the profile geometry, small features, and material selection of the components of a latch mechanism. 
         [0005]    Accordingly, while existing vehicle latch mechanisms are suitable, the need for improvement remains, particularly in providing a latch mechanism having improved noise dampening and energy absorption. 
       SUMMARY OF THE INVENTION 
       [0006]    In accordance with one embodiment, a latch is provided including a fork bolt configured to rotate between an unlatch position and a latched position. A detent is configured to cooperate with the forkbolt. A bumper includes an upper contact portion and an elongated lower portion. The bumper is configured to receive a striker when the fork bolt is in the latched position. A guide member includes a generally curved flexible portion. The flexible portion is configured to deflect about a first end to guide the striker towards the upper contact portion of the bumper. 
         [0007]    The above-described and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description, drawings, and appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which: 
           [0009]      FIG. 1  is a is a front view of a latch mechanism in a primary latched position according to an embodiment of the invention; 
           [0010]      FIG. 2  is a is a front view of a latch mechanism in a secondary latched position according to an embodiment of the invention; 
           [0011]      FIG. 3  is a front view of a bumper of the latch mechanism according to an embodiment of the invention; 
           [0012]      FIG. 4  is a perspective view of a guide member of a latch mechanism according to an embodiment of the invention; and 
           [0013]      FIG. 5  is a front view of a latch mechanism in a secondary latched position according to an embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    With reference to all of the FIGS., an exemplary latch  10  having improved sound performance is illustrated. The latch  10  is movable between a latched position and an unlatched position, and is configured to have a housing  20 . The latch  10  may be integrated into a component of a vehicle, such as the vehicle structure adjacent a lift gate, trunk, door, or any other operable component for example. 
         [0015]    The latch  10  includes a fork bolt  30  and a cooperating detent lever  50  for maintaining the fork bolt  30  in the latched position. The fork bolt  30  and the detent lever  50  are each pivotally mounted to the housing  20  of the latch  10  by a stud (not shown) positioned in holes  14 ,  16  respectively. The fork bolt  30  is biased in the direction of arrow F by a first biasing mechanism (not shown), and the detent lever  50  is biased in the direction of arrow D, into engagement with the fork bolt  30 , by a second biasing mechanism (not shown). In one embodiment, the first and second biasing mechanisms are coil or torsion springs. The fork bolt  30  has a slot or throat  32  for receiving and retaining a striker  80  (see  FIG. 2 ), such as a wire-loop striker for example, located on a complementary vehicle component, such as a lift gate or trunk. The fork bolt  30  also includes a primary shoulder  40  and an intermediate or secondary shoulder  34 . The secondary shoulder  34  of the fork bolt  30  includes a contact surface  38  configured to contact an engagement surface  54  of the detent lever  50  when rotating between an unlatched and a latched position 
         [0016]    The detent lever  50  includes a sector-shaped catch  52  configured to positively engage a surface  42 ,  36  of each of the primary and secondary shoulders  40 ,  34  to hold the fork bolt  30  against the bias of the first biasing mechanism in either a primary latched position ( FIG. 2 ) or secondary latched position ( FIG. 1 ) respectively. In one embodiment, a portion of the detent lever  50  is coupled to a release mechanism RM, illustrated schematically in  FIGS. 1 and 2 . Activation of the release mechanism RM applies a rotational force to the detent lever  50  in a direction opposite the direction indicated by arrow D. The aforementioned fork bolt  30  and detent lever  50  are illustrated as a non-limiting embodiment. Numerous other types or configurations of the fork bolt  30  and detent lever  50  are considered to be within the scope of an exemplary embodiment of the present invention. 
         [0017]    Referring now to  FIG. 3 , a bumper  60  is arranged between the housing  20  and the plane in which the fork bolt  30  and detent lever  50  rotate. The bumper  60  is positioned adjacent the interface between the sector-shaped catch  52  of the detent lever  50  and the shoulders  40 ,  34  of the fork bolt  30 . The bumper  60  includes an upper contact portion  62  and an elongated lower portion  66  arranged substantially perpendicularly to the upper contact portion  62 . In one embodiment, the bumper  60  is made from a flexible material, such as rubber or soft plastic for example. An engagement surface  64  of the upper contact portion  62  is angled towards the bend  68  between the upper and lower portions  62 ,  66  of the bumper  60 . The bumper  60  is configured to dampen sound generated by the contact between the fork bolt  30  and the striker wire  80 . Vibration and resultant noise of the striker wire  80  are thus absorbed from the portion  82  wedged between the upper contact portion  62  and the elongated lower portion  66 . 
         [0018]    As best illustrated in  FIG. 4 , a guide member  70  extends from near the opening  22  of the housing  20  for receiving and guiding the striker  80  to adjacent the bend  68  of the bumper  60 . The guide member  70  includes a rigid base  72  and a generally curved flexible portion  74  connected at a first end  76 . In one embodiment, at least a portion of the guide member  70 , such as the rigid base  72  for example, is formed integrally with the housing  20 . The flexible portion  74  is configured to rotate about the first end  76 , towards the base  72 , to guide the portion  82  of the striker wire  80  towards the bend  68  of the bumper  60 , between the upper and lower portions  62 ,  66 . 
         [0019]    As the striker wire  80  enters the opening  22  of the housing  20  and the throat  32  of the fork bolt  30 , the striker wire  80  applies a force to the primary shoulder  40 , thereby causing the fork bolt  30  to pivot in a direction opposite the direction indicated by arrow F, and thus the fork bolt  30  moves from an unlatched position to a latched position. During this movement, the contact surface  38  of the secondary shoulder  34  slidably contacts the engagement surface  54  of the detent lever  50  such that the detent lever  50  is rotated in a direction opposite the direction indicated by arrow D, away from the fork bolt  30 . 
         [0020]    The striker wire  80  moves along a substantially horizontal plane H (see  FIG. 4 ) as the fork bolt  30  rotates between an unlatched and a latched position. As the fork bolt  30  pivots from the primary latched position to the secondary latched position, portion  82  of the striker wire  80  slidably contacts the flexible portion  74  of the guide member  70  and applies a force thereto. As a result of the generally curved geometry of the flexible portion  74 , the deflection of the flexible portion  74  towards the base  72  increases as portion  82  approaches the free end  78  of the guide member  70 . The bending of the flexible portion  74  is complementary to the contour of the lower portion  66  of the bumper  60 . In one embodiment, the deflection of the flexible portion  74  is designed so as to guide portion  82  of the striker wire  80  along the lower portion  66  toward the upper portion  62 . When the striker  80  contacts the upper contact surface  64 , portion  82  is adjacent the free end  78  of the flexible portion  74 . Further rotation of the fork bolt  30  applies a force to the striker wire  80 , which causes portion  82  to wedge between the angled upper surface  64  and the elongated lower portion  66  adjacent the bend  68 , as illustrated in  FIG. 5 . 
         [0021]    Once the fork bolt  30  reaches the primary latched position, the detent lever  50  is biased into contact with the primary shoulder  40  of the fork bolt  30 , thereby preventing the fork bolt  30  from rotating towards the unlatched position until the detent lever  50  is mechanically released or disengaged. The bumper  60  prevents further rotation of the fork bolt  30  beyond the primary latched position. To open the latch  10 , actuation of the release mechanism RM coupled to the detent lever  50  causes the detent lever  50  to rotate out of engagement with the fork bolt  30 . The biasing mechanism acting on the fork bolt  30  causes the fork bolt  30  to pivot in the direction indicated by arrow F, towards the unlatched position. As the fork bolt  30  rotates open, the primary shoulder  40  applies a force to portion  82  of the striker wire  80 . The upper contact portion  62  and the elongated lower portion  66  of the bumper  70  flex to release the striker wire  80  such that the fork bolt  30  may further rotate relative to the housing  20  to an open, unlatched position. In addition, because the force retaining the free end  78  of the flexible portion  74  in a bent position is withdrawn, the flexible portion  74  biases back to its original position. In conjunction with the rotation of the fork bolt  30 , the movement of the curved flexible portion  74  about its first end  76  urges portion  82  of the striker wire  80  away from the bumper  60  and out of the opening  22  of the housing  20 . 
         [0022]    By incorporating the guide member  70  into the latch  10 , portion  82  of the striker wire  80  is coerced into a wedged position between the upper contact portion  62  and the elongated lower portion  66  of the bumper  60 . The guide member  70 , improves the reliability of engagement between the striker  80  and the sound dampening bumper  60 . 
         [0023]    While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.