Abstract:
A locking mechanism ( 1 ) for a vehicle seat includes a latch ( 11 ) that is to be interlocked with an opposite element (B) and is mounted to be pivotable about a first bearing bolt ( 13 ), at least one securing element ( 25, 31 ) that secures the latch ( 11 ) in the locked state, and a movable unlocking handle ( 42 ). The unlocking handle ( 42 ) is directly hinged to one of the securing elements ( 25, 31 ) by means of a single pivot point ( 48 ).

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a United States National Phase application of International Application PCT/EP2009/004774 and claims the benefit of priority under 35 U.S.C. §119 of German Patent Application DE 10 2008 033 304.2 filed Jul. 11, 2008, the entire contents of which are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention relates to a locking mechanism for a vehicle seat, in particular for a motor vehicle seat, having a latch for locking to a counter element, which latch is pivotably mounted about a bearing pin, at least one securing element which secures the latch in the locked state, and at least one locking handle. 
       BACKGROUND OF THE INVENTION 
       [0003]    Locking mechanisms of this type are known from use, in which a housing pivotably bears a metal latch, also denoted as a rotary catch, which cooperates with a metal counter element for locking, and a metal securing element which secures the latch in the locked state. The housing bears an unlocking handle in an integrally connected region which is articulated to the securing element by means of a connecting link. 
       SUMMARY OF THE INVENTION 
       [0004]    The object of the invention is to improve a locking mechanism of the type described in the introduction. 
         [0005]    According to the invention, a locking mechanism is provided for a vehicle seat. The locking mechanism comprises a latch for locking to a counter element, which is pivotably mounted about a first bearing pin. At least one securing element secures the latch in a locked state. A movable unlocking handle is articulated directly at one of the securing elements by means of a single point of articulation. 
         [0006]    A direct connection of the unlocking handle to one of the securing elements present and thus a direct control of the securing elements by means of the unlocking handle makes intermediate elements, such as a coupling rod or lever kinematics unnecessary, and avoids additional fastening clips or plastic coverings, optionally also mirror-symmetrical parts. 
         [0007]    In a preferred embodiment, which is also crash-safe, two securing elements are provided and namely one clamping element which is pretensioned and in the locked state acts on the latch, for example by acting on a functional surface of the latch by means of a clamping surface, and as a result exerting a closing moment on the latch, and a capture element which in the normal case is arranged at a short distance from the latch, in particular the functional surface thereof, and in the event of a crash, in particular by means of a capture surface, supports the latch, in particular on the functional surface thereof, and namely generally positively, so that possible opening of the clamping element counter to the pretensioning thereof has no effect. 
         [0008]    The integration of a stop acting in a damping manner has the advantage that, when striking the counter element, the lock housing is specifically (resiliently) deformed, whereby the impact of the counter element is damped. Relative to locking mechanisms with specifically configured cushioning elements attached to the receiver, an integral configuration or at least a material connection of the integrated first stop to the lock housing has the advantage of a smaller number of components. The lock housing in the region of this first stop is configured to be flexible, for example by material recesses being provided. 
         [0009]    After the counter element has resiliently deformed the lock housing to a specific degree due to the impact, it preferably strikes a second (metal) stop, for example on a lock cover, which is used to avoid too much deformation and damage to the lock housing by the impact of the counter element. The second stop is located in parallel, adjacent to the first stop, but displaced to the rear by said specific degree in the pivoted-in direction. 
         [0010]    Due to its resilience in the contact region with the counter element, the lock housing is used at the same time to ensure that the counter element is free of backlash. In this manner, oblique positions, counter element tolerances and position tolerances of the counter element and of the locking mechanism may be compensated or absorbed. 
         [0011]    A separation of the lock housing from the unlocking housing reduces the requirements for materials, in particular with regard to strength requirements in the region of the unlocking. Thus the material of the lock housing may be selected so that said lock housing has improved properties for implementing a stop and damping function. Additionally the geometry is simplified, which simplifies the tool design. The possibility of fastening a separate unlocking housing additionally makes it possible to use different customized variants of the unlocking, with an otherwise identical locking mechanism. 
         [0012]    The locking mechanism according to the invention may be used at different points of a vehicle seat, for example for attaching the entire vehicle seat to the floor or as a backrest lock for fastening the backrest to the vehicle structure. 
         [0013]    The invention is described in more detail hereinafter with reference to an exemplary embodiment shown in the drawings. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    In the drawings: 
           [0015]      FIG. 1  is a sectional view through the exemplary embodiment in the locked state with a counter element indicated; 
           [0016]      FIG. 2  is a sectional view through the exemplary embodiment in the unlocked state; 
           [0017]      FIG. 3  is a perspective view of the exemplary embodiment; 
           [0018]      FIG. 4  is a partial view of the exemplary embodiment in the region of the lock housing; 
           [0019]      FIG. 5  is a section view along the line V-V in  FIG. 4 ; 
           [0020]      FIG. 6  is a schematic view of a vehicle seat; 
           [0021]      FIG. 7  is a side view of the latch with the cap; 
           [0022]      FIG. 8  is a perspective view showing an embodiment of the cap; and 
           [0023]      FIG. 9  is a perspective view showing an alternative embodiment of the cap. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0024]    Referring to the drawings in particular, a locking mechanism  1  is provided in a motor vehicle for attaching a backrest  2  of a vehicle seat  3  to the vehicle structure. The locking mechanism  1  has a half-open lock housing  5 , with an approximately planar bottom surface and raised edges. The bottom surface is generally arranged in a plane defined by the direction of travel of the motor vehicle and by the vertical, which defines the directional information used hereinafter. The lock housing  5  is substantially closed by a lock cover  6  bearing against the lock housing  5  and approximately parallel to the bottom surface. The lock housing  5  is preferably formed from plastics, optionally with an insert part for increasing the strength, whilst the lock cover  6  is preferably a sheet metal part (steel or aluminum). 
         [0025]    The lock housing  5  and the lock cover  6  form a receiver  7  which opens in the direction of a counter element B, in order to receive said counter element for locking. In this case, of the locking mechanism  1  and the counter element B, one is fastened to the structure of the backrest  2  and the other to the vehicle structure. The counter element B may, for example, be a bolt or a clip. The portion of the counter element B to be received by the receiver  7  generally extends horizontally. The direction in which the counter element B is received by the receiver  7  might be denoted as the pivoted-in direction. The dimension of the receiver  7  perpendicular to the pivoted-in direction (and in the plane of the bottom surface of the lock housing  5 ) is preferably greater than the corresponding diameter of the counter element B for compensating clearance. 
         [0026]    The receiver  7  is designed on its base so that, in the pivoted-in direction, the region assigned to the lock cover  6  is set back relative to the region assigned to the lock housing  5 . The region assigned to the lock housing  5  is configured as an integrated first stop  5   a , against which the counter element B comes to bear when locked. The first stop  5   a  is configured to be resilient and acts in a damping manner. In the present case, the first stop  5   a  is formed in one piece with the lock housing  5 —preferably consisting of plastics (with an optional insert part) (i.e. the stop  5   a  during production of the lock housing  5  is configured in one piece with the regions of the lock housing  5  adjacent to the first stop  5   a , preferably by an injection-molding method). The region of the lock housing  5  located behind the first stop  5   a  in the pivoted-in direction has at least one (preferably a plurality of) material recess(es)  5   b , which influence the resilient and damping properties of the first stop  5   a . The lock housing  5  is, as a result, flexible in the region of the first stop  5   a . A second stop  6   a  is formed on the region of the base of the receiver  7  assigned to the lock cover  6 . Depending on the embodiment, the counter element B comes to bear against the second stop  6   a  during each locking process after deformation of the first stop  5   a  or only in the event of a crash or misuse. 
         [0027]    A latch  11  is pivotably mounted on a first bearing pin  13 , which in turn is fastened to the lock housing  5  (and to the lock cover  6 ) and protrudes perpendicularly from the bottom surface thereof, i.e. extends horizontally. In the present case, the first bearing pin  13 , which is preferably metal, is riveted to the lock housing  5  and caulked to the lock cover  6 . The first bearing pin  13  is preferably of hollow configuration, in order to receive a fastening means, for example a screw, by means of which the locking mechanism  1  is fastened during assembly to the associated structure. The latch  11  has a hook opening  15  for cooperating with the counter element B. 
         [0028]    On the latch  11  which is preferably made of metal (or of a different hard material) sits a cap  17 , preferably an injection-molded part made of plastics (or a part made of a different soft material). The cap  17  which is formed in one piece has a planar, flat region  17   a  which partially covers the side of the latch  11  (i.e. on one side) remote from the lock housing  5 , an edge region  17   b  protruding therefrom (preferably in a perpendicular manner), which (at least partially) covers the edge of the hook opening  15  and at least one projection  17   c  for fastening to the latch  11 . In the present case, the cap  17  has two projections  17   c  (or two pairs of projections  17   c ), which protrude parallel to the first bearing pin  13  from the flat region of the cap  17 . Each projection  17   c  (or each pair of projections  17   c ) is inserted through a suitable opening in the latch  11  and (preferably positively) connected to the latch  11 , for example clipped or preferably connected by ultrasonic-riveting, by means of a sonotrode. The cap  17  acts in a noise-damping manner when the counter element B is received by the hook opening  15  and comes to bear against the edge of the hook opening  15  (covered by the cap  17 , i.e. covered by the edge region  17   b  thereof). 
         [0029]    In the closed position of the latch  11 , the hook opening  15  traverses the receiver  7  in an approximately perpendicular manner and is open to the side. The dimension of the hook opening  15  (together with the cap  17 ) aligned in the pivoted-in direction is slightly greater than the diameter of the counter element B, whereby the edge of the hook opening  15  located further to the inside in the pivoted-in direction, is set back relative to the stop  5   a , so that the counter element B in the locked state of the locking mechanism  1  only bears against the stop  5   a  and not against said edge of the hook opening  15  located further to the inside in the pivoted-in direction. In the open position of the latch  11 , the hook opening  15  is open obliquely relative to the pivoted-in direction and traverses the receiver  7  in an oblique manner. The latch  11  is preferably pretensioned in the direction of the open position. 
         [0030]    The latch  11  has a functional surface  21  which in the locked position faces approximately in the direction of a second bearing pin  23 , which is arranged parallel to the first bearing pin  13  and is fastened in the same manner to the lock housing  5  (and to the lock cover  6 ). If an insert part is provided in the lock housing  5 , said insert part preferably holds the two bearing pins  13  and  23  at a defined distance from one another. The functional surface  21  is, for example, curved in the shape of a circular arc and of concave configuration but may also be planar. On the second bearing pin  23  a clamping element  25  is pivotably mounted, which is pretensioned toward the latch  11 . In the locked state the clamping element  25  exerts a closing moment on the latch  11  as a securing element by means of a clamping surface  29  curved eccentrically to the second bearing pin  23 , which is in non-self-locking contact with the functional surface  21 . The clamping surface  29  is, for example, curved in the shape of a circular arc and of convex configuration. 
         [0031]    A capture element  31  is arranged (relative to the second bearing pin  23 ) axially adjacent to the clamping element  25  on the side remote from the lock housing  5 , and also pivotably mounted on the second bearing pin  23 , i.e. aligned with the clamping element  25 . The capture element  31  has a capture surface  33  which is located in the vicinity of the clamping surface  29 , but in the locked state is spaced apart from the functional surface  21 . The capture surface  33  is, for example, curved in the shape of a circular arc and of convex configuration, but may also be planar. The capture element  31  may be mounted in its center of gravity. The capture element  31  and the clamping element  25  are mechanically connected to one another with free travel, for example by means of a slot-pin guide or an axially protruding drive element. In the event of a crash, if the latch  11  were to be subjected to an opening moment and push the clamping element  25  slightly away, the capture surface  33  would come to bear against the functional surface  21 , without an opening moment being able to be transmitted. Thus the capture element  31  serves for supporting the latch  11  and as a further securing element prevents an opening thereof. 
         [0032]    The locking mechanism  1  further comprises an unlocking housing  40  which is configured separately and is fastened to the upper end of the lock housing  5  and the lock cover  6 . In the present case, the unlocking housing  40  is pushed in the horizontal direction (“laterally”) onto the lock housing  5  and clipped to the lock cover  6 , the clipped connection between the lock housing  5  and the lock cover  6  being secured against a release of the connection by pushing on the unlocking housing  40 . The unlocking housing  40  is substantially configured as a vertical duct, within which an unlocking handle  42  is arranged and is accessible—generally from above. The unlocking handle  42  is mounted in the unlocking housing  40 , manually pivotable about an unlocking axis  43  parallel to the bearing pins  13  and  23 . Resiliently coupled to the unlocking handle  42  is an indicator  45  which is guided in a longitudinally displaceable manner in the unlocking housing  40 , and may partially extend from said unlocking housing in order to display the unlocked state of the locking mechanism  1 . The resilient coupling of the indicator  45  has the purpose of avoiding damage to the extended indicator  45  in the event of misuse. The resilient coupling is implemented, for example, by means of a spring or a further resilient element, by means of which the unlocking handle  42  activates and extends the indicator  45 . According to the type and geometry of the resilient element, for retracting the indicator  45 , i.e. when the locked state of the locking mechanism  1  has to be displayed, temporary, positive contact may be provided between the indicator  45  and the unlocking handle  42 . The indicator  45  is at least partially colored in a signal color which is preferably clearly differentiated from the color of the unlocking housing  40  or the covers thereof. 
         [0033]    The unlocking handle  42  has at its lower end an actuating element  46 . The actuating element  46  is in the present case configured as an integrally formed pin, which protrudes parallel to the unlocking axis  43  from the unlocking handle  42 . The actuating element  46  acts in an articulated manner on the capture element  31  so that a direct point of articulation  48  between the unlocking handle  42  and the capture element  31  is formed. The point of articulation  48  is arranged offset (parallel) to the unlocking axis  43 . In the present case, the point of articulation  48  is produced by the rounded actuating element  46  coming to rest in a radiused jaw-like receiver of the capture element  31 . By the defined relative position of the second bearing pin  23  and the unlocking axis  43 , the point of articulation  48  is maintained in all positions. However, optional securing is possible by the lips of the jaw-like receiver of the capture element  31  engaging behind the actuating element  46  after the resilient deformation thereof. 
         [0034]    In the locked state of the locking mechanism  1 , the counter element B is located in the receiver  7  and in the hook opening  15  of the closed latch  11 , the clamping element  25  secures the latch  11 , the capture element  31  is slightly spaced apart from the functional surface  21 , the unlocking handle  42  is in its initial position and the indicator  45  is retracted. If the unlocking handle  42  is pivoted, the indicator  45  is extended, and by means of the point of articulation  48  the capture element  31  is also pivoted, i.e. the capture surface  33  moves away from the functional surface  21 . The capture element  31  drives the clamping element  25 , so that the latch  11  is no longer secured. Driven by one of the two securing elements or by individual pretensioning, the latch  11  opens. Due to the pivoting motion of the latch  11 , the hook opening  15  is pulled back from the receiver  7  and releases the counter element B, which moves away relative to the locking mechanism  1  counter to the pivoted-in direction. Preferably, in the unlocked state of the locking mechanism  1  the latch  11  and the capture element  31  bear against one another for mutual support at a point which in each case is different from the functional surface  21  and the capture surface  33 , so that the hook opening  15  remains in a ready-to-receive state. 
         [0035]    If in this unlocked state the counter element B again enters the receiver  7  and comes to bear against the edge (covered by the cap  17 ) of the hook opening  15 , the counter element B presses the latch  11  into its closed position. The clamping element  25  moves (due to its pretensioning) along the functional surface  21 , as does the capture element  31  which is driven by the clamping element  25  or pivots due to its own pretensioning, whereby said two securing elements secure the latch  11  again. The pivoting capture element  31  pivots the unlocking handle  42  again into its initial position which at the same time retracts the indicator  45 . 
         [0036]    While specific embodiments of the invention have been described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.