Abstract:
In the case of a fitting ( 5 ) for a vehicle seat ( 1 ), in particular for a motor vehicle seat, having a lockable latching fitting ( 7 ) for the fine adjustment of the inclination and locking of a backrest ( 3 ) between a plurality of use positions, and a pivotable free-pivoting device ( 11, 23 ) for moving the backrest ( 3 ) beyond the use positions, coupling means ( 35 ) are provided, by means of which unlocking of the free-pivoting device ( 11, 23 ) only takes place after unlocking of the latching fitting ( 7 ).

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]    This is a continuation of PCT/EP02/03208, which was filed Mar. 22, 2002, published in German, and is entirely incorporated herein by reference. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention relates to a fitting for a vehicle seat, in particular for a motor vehicle seat, having a lockable latching fitting for the fine adjustment of the inclination of the backrest between a plurality of use positions and for selectively locking the backrest in the use positions, and a lockable free-pivoting device for moving the backrest beyond the use positions.  
           [0003]    In order, in the case of known vehicle seats, to achieve a table position, in which the backrest is in an approximately horizontal position, a fitting has been designed which combines an unlockable latching fitting, as is customary for the usual adjustment of the inclination of the backrest, with an unlockable, eccentric free-pivoting device, as is customary for two-door motor vehicles, in order to obtain the necessary pivoting angle. A disadvantage in this case is that because of the asynchronous locking of the latching fitting, after actuation of the free-pivoting device the backrest is no longer securely locked, and that the effect of an additional force (backrest compensation spring of the latching fitting) may result in inadvertent movements of the system, as a result of which there is, for example, the risk of fingers becoming jammed.  
         BRIEF SUMMARY OF THE INVENTION  
         [0004]    One aspect of the present invention is the provision of an improved fitting for a vehicle seat, in particular for a motor vehicle seat, having a lockable latching fitting for the fine adjustment of the inclination of the backrest between a plurality of use positions and for respectively locking the backrest in the use positions, a lockable free-pivoting device for moving the backrest beyond the use positions, and coupling means by way of which unlocking of the free-pivoting device only takes place after unlocking of the latching fitting.  
           [0005]    By virtue of the coupling means, by way of which unlocking of the free-pivoting device only takes place after unlocking of the latching fitting, in the case of a vehicle seat having two fittings according to the invention, the torsions and angular differences which occur over the width of the vehicle seat are eliminated and a secure locking of both latching fittings in the same angular positions is ensured. The coupling means can be configured in such a manner that a positively controlled unlocking of the free-pivoting device takes place, which also facilitates the actuation. Apart from the case of a table function, the invention can also be used in the case of a customary free-pivoting function, so that actuating processes which are separate per se (adjustment of the inclination over small angles, and free-pivoting over large angles) can be combined in a common actuating option.  
           [0006]    In the case of a common design of the latching fitting, which design can be produced in a simple manner with a fitting lower part and a rotatable fitting upper part, and a design of the eccentric free-pivoting device with a pivotable catch or hook for locking to a bolt or the like fixed on the structure, the coupling means are preferably provided between the fitting upper part and the catch, so that the catch opens at the latest in a certain angular position of the backrest. A coupler for this purpose, which coupler is preferably of rigid design and is fitted in an articulated manner and is simple to produce and fit, i.e. is a cost-effective tractive (e.g., pulling) means, can be provided with an idle stroke device, for example a slot and tenon guide, in order to remain inactive within various use positions and only to respond at a relatively great pivoting angle.  
           [0007]    A safety device is preferably provided. When pivoting back the backrest, the safety device functions so that locking of the latching fitting only takes place after locking of the free-pivoting device. In the case of the above-mentioned, common design, the safety device can be designed as a pivotable, two-armed lever which uses the one arm to monitor the position of the latching bolt and uses the other arm to interact with a control element of the fitting upper part. The control element is effective in the circumferential direction, and it is preferably provided at a certain angle on the fitting upper part in the manner of a step, or the like. As a result, locking of the latching fitting is blocked until the locking of the free-pivoting device has taken place. The safety device operates in the rear direction of movement to complement the coupling means, which acts in the forward direction of movement.  
           [0008]    In a preferred design, a monitoring device is also provided. The monitoring device functions so that the unlocking and locking of the free-pivoting device only takes place at certain settings of the latching fitting, in particular only if the backrest has been pivoted forward relative to the seat part. As a result, unlocking of the free-pivoting device in the use positions can be prevented. In addition, the sequence of movement and the relative movement between the components can be controlled better. For example, striking of the backrest against the vehicle roof lining can be avoided. In the case of the above-mentioned, common design, the monitoring device can be effective between the catch and the control element of the fitting upper part. The control element extends over a certain angular region about the rotational axis and forms a type of guide for a control finger of the catch. The control element, for example an elongate, curved cam or a disk cam, can simultaneously form the control element for the safety device.  
           [0009]    The invention is not restricted to vehicle seats with table functions and free-pivoting functions of the backrest. It can also be used, for example, if, for a package position or the like in a rear row of seats, a foot is only to be disengaged if the backrest has been folded flat onto the seat part. The free-pivoting device can then generally be seen as a folding device for the entire vehicle seat about the front foot. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    The invention is explained in greater detail below with reference to two exemplary embodiments illustrated in the drawing, in which:  
         [0011]    [0011]FIG. 1 shows a partial view of the structure of a vehicle seat with upholstery indicated, in a use position,  
         [0012]    [0012]FIG. 2 shows an illustration corresponding to FIG. 1 in the table position,  
         [0013]    [0013]FIG. 3 shows a view of the first exemplary embodiment shortly before the catch is unlocked,  
         [0014]    [0014]FIG. 4 shows an illustration corresponding to FIG. 3 shortly after the catch is unlocked,  
         [0015]    [0015]FIG. 5 shows an illustration corresponding to FIG. 3 in the table position,  
         [0016]    [0016]FIG. 6 shows an illustration corresponding to FIG. 3 shortly before the locking of the catch,  
         [0017]    [0017]FIG. 7 shows a view of the second exemplary embodiment in a use position, and  
         [0018]    [0018]FIG. 8 shows an illustration corresponding to FIG. 7 shortly after the catch is unlocked. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]    In the first exemplary embodiment, a vehicle seat  1  for a motor vehicle has a respective fitting, which is denoted in its entirety by the numeral  5 , on both of the sides of the vehicle seat. The fitting  5  is for adjusting the backrest  3  of the vehicle seat  1  relative to the seat part  4  of the vehicle seat. The backrest  3  can be adjusted between a plurality of use positions, for which purpose the fitting  5  has a latching fitting  7  for fine adjustment purposes. The latching fitting  7  comprises a fitting lower part  9  which is welded onto an adapter  11 , and a fitting upper part  15  which can be rotated relative to the fitting lower part  9  about an axis of rotation  13  and is welded onto a further adapter  17  for fastening to the structure of the backrest  3 .  
         [0020]    The latching fitting  7  can be locked and unlocked in a manner known per se, by way of movable latches (not illustrated). The latches for locking and unlocking the latching fitting  7  can be controlled by a shaft which is in alignment with the axis of rotation  13  and acts at the same time as a transmission rod between the fittings  5  on both sides of the vehicle seat  1 . Means in the interior of the latching fitting  7  cause the engagement of the latches to be restricted preferably to certain regions of relative angle positions between the fitting upper part  15  and fitting lower part  9 .  
         [0021]    The adapter  11 , which is fitted to the fitting lower part  9 , is pivotably mounted on the structure of the seat part  4 , for example on the seat frame, by way of an adapter bearing bolt  20 . In the use positions of the backrest  3 , the adapter  11  rests on a latching bolt  22  which is fixed on the seat-part structure and is likewise fitted, for example, to the seat frame. The cylindrical latching bolt  22  is engaged around over approximately half of its circumference by a hook mouth of a catch  23 . This mouth is open in the direction of travel and is pivotably mounted on the adapter  11  by way of a catch bearing bolt  25 . A spring, which is hooked at one end on the adapter  11  and at the other end eccentrically on the catch  23  and is referred to in the following as catch spring  27 , causes the catch  23  to be prestressed in the closing direction, i.e. toward the latching bolt  22 .  
         [0022]    Furthermore, a safety lever  31  is mounted pivotably on the catch bearing bolt  25 . The safety lever  31  has a long arm  31 ′, which points to the rear, which is opposite to the direction of travel. The safety lever  31  further includes a short arm  31 ″, which is angled downward with respect thereto. A tension spring, referred to below as lever spring  33 , engages on the long arm  31 ′ of the safety lever  31  and pulls the short arm  31 ″ into contact against the latching bolt  22 . A coupler  35  is articulated on the catch  23  with its one end eccentrically to the catch bearing bolt  25 . The coupler  35  is arranged with respect to the safety lever  31  on the side remote from the catch  23 . The other end of the coupler  35  has an elongated hole  37  which encloses, in the manner of a slot and tenon guide, a coupling pin  39  which protrudes from the fitting upper part  15  and is arranged eccentrically with respect to the axis of rotation  13 . A stop cam  41  is provided on the fitting upper part  15 , radially between the coupling pin  39  and the axis of rotation  13 , in the plane of the safety lever  31 . The stop cam  41  projects from the fitting upper part  15  in the axial direction with respect to the axis of rotation  13  at least by approximately the material thickness of the safety lever  31 .  
         [0023]    For the free pivoting in two-door motor vehicles or for free pivoting to a table position of the backrest  3  or for free pivoting to a package position of the vehicle seat  1  in a rear row of seats  2 , referred to in the following in short as free pivoting, the catch  23  can be disengaged, preferably by way of a manual actuating device, so that the fitting  5  functions as a free-pivoting device. Then, the backrest  3  together with the fitting  5  can be pivoted forward about the adapter bearing bolt  20 , i.e. eccentrically with respect to the axis of rotation  13 .  
         [0024]    For this purpose, first of all the latching fitting  7  is unlocked on both sides of the vehicle seat  1  and the backrest  3  is pivoted forward about the axis of rotation  13 . In this case, the coupling pin  39  moves within the elongated slot  37 , at its rear end. The latching fitting  7  for the time being remains unlocked in these angular positions between the fitting upper part  15  and fitting lower part  9 , even if the actuating device is released. After the coupling pin  39  has reached the end of the elongated hole  37 , the coupling pin  39  carries along the catch  23  via the coupler  35 . The catch  23  pivots counter to the force of the catch spring  27  until it is in contact against a catch stop  43  and releases the latching bolt  22 . The fitting upper part  15  passes into contact against an upper-part stop on the adapter  11 .  
         [0025]    With a further torque applied to the backrest  3 , the adapter  11 , which is now unlocked, begins to pivot about the adapter bearing bolt  20  carrying along the entire fitting  5 . As soon as the short arm  31 ″ is removed from the latching bolt  22  by this eccentric free-pivoting movement, the lever spring  33  pulls the safety lever  31  against a lever stop  47 . The free end of the long arm  31 ′ of the safety lever  31  is now at approximately the same radial distance from the axis of rotation  13  as the stop cam  41 . With this configuration of the components, the free-pivoting movement of the backrest  3  about the adapter bearing bolt  22  continues until the desired end position of the backrest  3 , for example the table position with the front side of the backrest  3  in contact against the upper side of the seat part  4 , is reached.  
         [0026]    During the return into a use position, a torque is first of all applied to the backrest  3  so that the fitting upper part  15  pivots back about a few angular degrees until the stop cam  41  comes into contact against the free end of the long arm  31 ′ of the safety lever  31 . The fitting upper part  15  is now held relative to the fitting lower part  9  in a position in which it cannot be locked. The relative movement between the stop cam  41  and safety lever  31  causes the coupler  35  to move slightly toward the catch  23 , with the result that the catch can pivot somewhat in the closing direction owing to the force of the catch spring  27 .  
         [0027]    The backrest  3  together with the fitting  5  is pivoted back about the adapter bearing bolt  20  until a run-on slope of the catch  23  comes into contact against the latching bolt  22 , and the catch  23  then pivots in the opening direction counter to the force of the catch spring  27 , utilizing the slot and tenon guide between the elongated hole  37  and coupling pin  39  until the catch  23  can use the hook mouth to engage on the latching bolt  22  and locks the adapter  11 . The latching bolt  22  then presses the short arm  31 ″ of the safety lever  31  to the side, as a result of which the long arm  31 ′ of the safety lever  31  is pivoted away from the stop cam  41 .  
         [0028]    The fitting upper part  15  can now be pivoted relative to the fitting lower part  9  in the direction of a locking position. The coupling pin  39  moves again relative to the coupler  35  within its elongated slot  37 . As soon as the backrest  3  has reached the desired use position, the latching fitting  7  can lock synchronously together with the latching fitting on the other side of the vehicle seat  1 .  
         [0029]    The second exemplary embodiment largely corresponds with the first exemplary embodiment, so identical components bear reference numbers incremented by  100 . The fitting  105  likewise has a latching fitting  107  with a fitting lower part  109  and a fitting upper part  115  which can be rotated relative to the latter about an axis of rotation  113 . The adapter  111 , which can be pivoted about the adapter bearing bolt  120  fixed on the seat-part structure, is fitted fixedly on the fitting lower part  109 . The catch  123  is locked by the latching bolt  122 , which is fixed on the seat-part structure. The coupler  135  is provided between the catch  123  and the fitting upper part  115 . During the pivoting back process, the safety lever  131  prevents locking of the latching fitting  107  by coming in the pivoting direction into contact against a control cam  141  which is fixed on the fitting upper part, is bent approximately in the shape of a quarter of a circle about the axis of rotation  113  and corresponds in this function to the stop cam  41  of the first exemplary embodiment. The interaction of the above-mentioned components, also with the further, corresponding components, takes place as in the first exemplary embodiment.  
         [0030]    The control cam  141  has further functions additionally to the first exemplary embodiment. A control finger  123 ′ is provided on the catch  123 , at the end remote from the hook mouth for the latching bolt  122 . The control cam  141  projects with respect to the stop cam  41  of the first exemplary embodiment from the fitting upper part  115  in the axial direction with respect to the axis of rotation  113  at least to an extent such that it corresponds to the sum of the material thicknesses of safety lever  131  and control finger  123 ′, and extends over a relatively large angular region in the circumferential direction.  
         [0031]    In the use positions, the control finger  123 ′ is situated in contact against the radially outer side of the control cam  141 , slides, during pivoting movements of the latching fitting  107 , along this outer side of the control cam  141  and therefore prevents unlocking of the catch  123 . As soon as the fitting upper part  115  has pivoted forward sufficiently far, the control cam  141  releases the control finger  123 ′, and the catch  123  can pivot in the opening direction. In the process, the control finger  123 ′ passes radially further inward with respect to the latching fitting  107  and now prevents a closing pivoting movement of the fitting upper part  115  with the control cam  141 .